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Sample records for mice lacking synapsin

  1. Alterations in Brain Inflammation, Synaptic Proteins, and Adult Hippocampal Neurogenesis during Epileptogenesis in Mice Lacking Synapsin2.

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    Deepti Chugh

    Full Text Available Synapsins are pre-synaptic vesicle-associated proteins linked to the pathogenesis of epilepsy through genetic association studies in humans. Deletion of synapsins causes an excitatory/inhibitory imbalance, exemplified by the epileptic phenotype of synapsin knockout mice. These mice develop handling-induced tonic-clonic seizures starting at the age of about 3 months. Hence, they provide an opportunity to study epileptogenic alterations in a temporally controlled manner. Here, we evaluated brain inflammation, synaptic protein expression, and adult hippocampal neurogenesis in the epileptogenic (1 and 2 months of age and tonic-clonic (3.5-4 months phase of synapsin 2 knockout mice using immunohistochemical and biochemical assays. In the epileptogenic phase, region-specific microglial activation was evident, accompanied by an increase in the chemokine receptor CX3CR1, interleukin-6, and tumor necrosis factor-α, and a decrease in chemokine keratinocyte chemoattractant/ growth-related oncogene. Both post-synaptic density-95 and gephyrin, scaffolding proteins at excitatory and inhibitory synapses, respectively, showed a significant up-regulation primarily in the cortex. Furthermore, we observed an increase in the inhibitory adhesion molecules neuroligin-2 and neurofascin and potassium chloride co-transporter KCC2. Decreased expression of γ-aminobutyric acid receptor-δ subunit and cholecystokinin was also evident. Surprisingly, hippocampal neurogenesis was reduced in the epileptogenic phase. Taken together, we report molecular alterations in brain inflammation and excitatory/inhibitory balance that could serve as potential targets for therapeutics and diagnostic biomarkers. In addition, the regional differences in brain inflammation and synaptic protein expression indicate an epileptogenic zone from where the generalized seizures in synapsin 2 knockout mice may be initiated or spread.

  2. Autism-related behavioral abnormalities in synapsin knockout mice.

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    Greco, Barbara; Managò, Francesca; Tucci, Valter; Kao, Hung-Teh; Valtorta, Flavia; Benfenati, Fabio

    2013-08-15

    Several synaptic genes predisposing to autism-spectrum disorder (ASD) have been identified. Nonsense and missense mutations in the SYN1 gene encoding for Synapsin I have been identified in families segregating for idiopathic epilepsy and ASD and genetic mapping analyses have identified variations in the SYN2 gene as significantly contributing to epilepsy predisposition. Synapsins (Syn I/II/III) are a multigene family of synaptic vesicle-associated phosphoproteins playing multiple roles in synaptic development, transmission and plasticity. Lack of SynI and/or SynII triggers a strong epileptic phenotype in mice associated with mild cognitive impairments that are also present in the non-epileptic SynIII(-/-) mice. SynII(-/-) and SynIII(-/-) mice also display schizophrenia-like traits, suggesting that Syns could be involved in the regulation of social behavior. Here, we studied social interaction and novelty, social recognition and social dominance, social transmission of food preference and social memory in groups of male SynI(-/-), SynII(-/-) and SynIII(-/-) mice before and after the appearance of the epileptic phenotype and compared their performances with control mice. We found that deletion of Syn isoforms widely impairs social behaviors and repetitive behaviors, resulting in ASD-related phenotypes. SynI or SynIII deletion altered social behavior, whereas SynII deletion extensively impaired various aspects of social behavior and memory, altered exploration of a novel environment and increased self-grooming. Social impairments of SynI(-/-) and SynII(-/-) mice were evident also before the onset of seizures. The results demonstrate an involvement of Syns in generation of the behavioral traits of ASD and identify Syn knockout mice as a useful experimental model of ASD and epilepsy. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Effects of different levels of food restriction on passive-avoidance memory and the expression of synapsin I in young mice.

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    Deng, L; Wu, Z-N; Han, P-Z

    2009-01-01

    The present study investigated the effects of food restriction (FR) on memory and the expression of synapsin I in the brain of young mice. The results showed that 20% FR did not retard the body weight gain of mice, while the 60% and 80% FR reduced the mice's body weight. The memory after 24 hr of learning was not changed by FR, whereas long-term memory was improved significantly in 20% FR mice. In addition, 60% and 80% FR did not impair the mice's memory. The transcriptional expression of synapsin I in mice brain was up-regulated by 20% FR, and down-regulated by 60% and 80% FR.

  4. Electroencephalographic characterization of seizure activity in the synapsin I/II double knockout mouse

    DEFF Research Database (Denmark)

    Etholm, Lars; Lindén, Henrik; Eken, Torsten

    2011-01-01

    We present a detailed comparison of the behavioral and electrophysiological development of seizure activity in mice genetically depleted of synapsin I and synapsin II (SynDKO mice), based on combined video and surface EEG recordings. SynDKO mice develop handling-induced epileptic seizures...... at the age of 2months. The seizures show a very regular behavioral pattern, where activity is initially dominated by truncal muscle contractions followed by various myoclonic elements. Whereas seizure behavior goes through clearly defined transitions, cortical activity as reflected by EEG recordings shows...... a more gradual development with respect to the emergence of different EEG components and the frequency of these components. No EEG pattern was seen to define a particular seizure behavior. However, myoclonic activity was characterized by more regular patterns of combined sharp waves and spikes. Where...

  5. Synapsin determines memory strength after punishment- and relief-learning.

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    Niewalda, Thomas; Michels, Birgit; Jungnickel, Roswitha; Diegelmann, Sören; Kleber, Jörg; Kähne, Thilo; Gerber, Bertram

    2015-05-13

    Adverse life events can induce two kinds of memory with opposite valence, dependent on timing: "negative" memories for stimuli preceding them and "positive" memories for stimuli experienced at the moment of "relief." Such punishment memory and relief memory are found in insects, rats, and man. For example, fruit flies (Drosophila melanogaster) avoid an odor after odor-shock training ("forward conditioning" of the odor), whereas after shock-odor training ("backward conditioning" of the odor) they approach it. Do these timing-dependent associative processes share molecular determinants? We focus on the role of Synapsin, a conserved presynaptic phosphoprotein regulating the balance between the reserve pool and the readily releasable pool of synaptic vesicles. We find that a lack of Synapsin leaves task-relevant sensory and motor faculties unaffected. In contrast, both punishment memory and relief memory scores are reduced. These defects reflect a true lessening of associative memory strength, as distortions in nonassociative processing (e.g., susceptibility to handling, adaptation, habituation, sensitization), discrimination ability, and changes in the time course of coincidence detection can be ruled out as alternative explanations. Reductions in punishment- and relief-memory strength are also observed upon an RNAi-mediated knock-down of Synapsin, and are rescued both by acutely restoring Synapsin and by locally restoring it in the mushroom bodies of mutant flies. Thus, both punishment memory and relief memory require the Synapsin protein and in this sense share genetic and molecular determinants. We note that corresponding molecular commonalities between punishment memory and relief memory in humans would constrain pharmacological attempts to selectively interfere with excessive associative punishment memories, e.g., after traumatic experiences. Copyright © 2015 Niewalda et al.

  6. Synapsin Determines Memory Strength after Punishment- and Relief-Learning

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    Niewalda, Thomas; Michels, Birgit; Jungnickel, Roswitha; Diegelmann, Sören; Kleber, Jörg; Kähne, Thilo

    2015-01-01

    Adverse life events can induce two kinds of memory with opposite valence, dependent on timing: “negative” memories for stimuli preceding them and “positive” memories for stimuli experienced at the moment of “relief.” Such punishment memory and relief memory are found in insects, rats, and man. For example, fruit flies (Drosophila melanogaster) avoid an odor after odor-shock training (“forward conditioning” of the odor), whereas after shock-odor training (“backward conditioning” of the odor) they approach it. Do these timing-dependent associative processes share molecular determinants? We focus on the role of Synapsin, a conserved presynaptic phosphoprotein regulating the balance between the reserve pool and the readily releasable pool of synaptic vesicles. We find that a lack of Synapsin leaves task-relevant sensory and motor faculties unaffected. In contrast, both punishment memory and relief memory scores are reduced. These defects reflect a true lessening of associative memory strength, as distortions in nonassociative processing (e.g., susceptibility to handling, adaptation, habituation, sensitization), discrimination ability, and changes in the time course of coincidence detection can be ruled out as alternative explanations. Reductions in punishment- and relief-memory strength are also observed upon an RNAi-mediated knock-down of Synapsin, and are rescued both by acutely restoring Synapsin and by locally restoring it in the mushroom bodies of mutant flies. Thus, both punishment memory and relief memory require the Synapsin protein and in this sense share genetic and molecular determinants. We note that corresponding molecular commonalities between punishment memory and relief memory in humans would constrain pharmacological attempts to selectively interfere with excessive associative punishment memories, e.g., after traumatic experiences. PMID:25972175

  7. A role for synapsin in FKBP51 modulation of stress responsiveness: Convergent evidence from animal and human studies.

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    Schmidt, Ulrike; Buell, Dominik R; Ionescu, Irina A; Gassen, Nils C; Holsboer, Florian; Cox, Marc B; Novak, Bozidar; Huber, Christine; Hartmann, Jakob; Schmidt, Mathias V; Touma, Chadi; Rein, Theo; Herrmann, Leonie

    2015-02-01

    Both the molecular co-chaperone FKBP51 and the presynaptic vesicle protein synapsin (alternatively spliced from SYN1-3) are intensively discussed players in the still insufficiently explored pathobiology of psychiatric disorders such as major depression, schizophrenia and posttraumatic stress disorder (PTSD). To address their still unknown interaction, we compared the expression levels of synapsin and five other neurostructural and HPA axis related marker proteins in the prefrontal cortex (PFC) and the hippocampus of restrained-stressed and unstressed Fkbp5 knockout mice and corresponding wild-type littermates. In addition, we compared and correlated the gene expression levels of SYN1, SYN2 and FKBP5 in three different online datasets comprising expression data of human healthy subjects as well as of predominantly medicated patients with different psychiatric disorders. In summary, we found that Fkbp5 deletion, which we previously demonstrated to improve stress-coping behavior in mice, prevents the stress-induced decline in prefrontal cortical (pc), but not in hippocampal synapsin expression. Accordingly, pc, but not hippocampal, synapsin protein levels correlated positively with a more active mouse stress coping behavior. Searching for an underlying mechanism, we found evidence that deletion of Fkbp5 might prevent stress-induced pc synapsin loss, at least in part, through improvement of pc Akt kinase activity. These results, together with our finding that FKBP5 and SYN1 mRNA levels were regulated in opposite directions in the PFC of schizophrenic patients, who are known for exhibiting an altered stress-coping behavior, provide the first evidence of a role for pc synapsin in FKBP51 modulation of stress responsiveness. This role might extend to other tissues, as we found FKBP5 and SYN1 levels to correlate inversely not only in human PFC samples but also in other expression sites. The main limitation of this study is the small number of individuals included in the

  8. Nonsense-mediated mRNA decay and loss-of-function of the protein underlie the X-linked epilepsy associated with the W356× mutation in synapsin I.

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    Maila Giannandrea

    Full Text Available Synapsins are a family of neuronal phosphoproteins associated with the cytosolic surface of synaptic vesicles. Experimental evidence suggests a role for synapsins in synaptic vesicle clustering and recycling at the presynaptic terminal, as well as in neuronal development and synaptogenesis. Synapsin knock-out (Syn1(-/- mice display an epileptic phenotype and mutations in the SYN1 gene have been identified in individuals affected by epilepsy and/or autism spectrum disorder. We investigated the impact of the c.1067G>A nonsense transition, the first mutation described in a family affected by X-linked syndromic epilepsy, on the expression and functional properties of the synapsin I protein. We found that the presence of a premature termination codon in the human SYN1 transcript renders it susceptible to nonsense-mediated mRNA decay (NMD. Given that the NMD efficiency is highly variable among individuals and cell types, we investigated also the effects of expression of the mutant protein and found that it is expressed at lower levels compared to wild-type synapsin I, forms perinuclear aggregates and is unable to reach presynaptic terminals in mature hippocampal neurons grown in culture. Taken together, these data indicate that in patients carrying the W356× mutation the function of synapsin I is markedly impaired, due to both the strongly decreased translation and the altered function of the NMD-escaped protein, and support the value of Syn1(-/- mice as an experimental model mimicking the human pathology.

  9. Microwave radiation, in the absence of hyperthermia, has no detectable effect on synapsin I levels or phosphorylation

    International Nuclear Information System (INIS)

    Browning, M.D.; Haycock, J.W.

    1988-01-01

    Recent reports have indicated that microwave radiation can produce effects on a variety of cell types in vitro. To determine whether microwave radiation might be neurotoxic, the effects of microwave radiation on synapsin I have been examined. Synapsin I is a neuron-specific phosphoprotein that is present in all neurons, where it is localized to the presynaptic terminal and is associated with synaptic vesicles. O'Callaghan and Miller have demonstrated that studies of such neuron-specific proteins can provide reliable indices of neurotoxicity. We have used a radioimmunoassay for synapsin I to determine whether microwave irradiation has any effect on the levels of synapsin I. Neither acute nor chronic exposure to microwave irradiation had any detectable effect on synapsin I levels. We have also examined the calcium-dependent phosphorylation of synapsin I in synaptosomes isolated from rats that had been subjected to microwave radiation. The phosphorylation of synapsin I in synaptosomes reflects numerous components of the presynaptic aspect of neuronal transmission. At intensities below that required to produce mild hyperthermia, no effects of microwave irradiation were seen on synapsin I phosphorylation

  10. Overexpression of synapsin Ia in the rat calyx of Held accelerates short-term plasticity and decreases synaptic vesicle volume and active zone area

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    Mariya eVasileva

    2013-12-01

    Full Text Available Synapsins are synaptic vesicle (SV proteins organizing a component of the reserve pool of vesicles at most central nervous system synapses. Alternative splicing of the three mammalian genes results in multiple isoforms that may differentially contribute to the organization and maintenance of the synaptic vesicle-pools. To address this, we first characterized the expression pattern of synapsin isoforms in the rat calyx of Held. At postnatal day 16, synapsins Ia, Ib, IIb and IIIa were present, while IIa – known to sustain repetitive transmission in glutamatergic terminals – was not detectable. To test if the synapsin I isoforms could mediate IIa-like effect, and if this depends on the presence of the E-domain, we overexpressed either synapsin Ia or synapsin Ib in the rat calyx of Held via recombinant adeno-associated virus-mediated gene transfer. Although the size and overall structure of the perturbed calyces remained unchanged, short-term depression and recovery from depression were accelerated upon overexpression of synapsin I isoforms. Thus, at the calyx of Held, synapsin Ia may not substitute for the synapsin IIa-function reported for hippocampal synapses. Using electron microscopic three-dimensional reconstructions we found a redistribution of SV clusters proximal to the active zones (AZ alongside with a decrease of both AZ area and SV volume. The number of SVs at individual AZs was strongly reduced. Hence, our data indicate that the amount of synapsin Ia expressed in the calyx regulates the rate and extent of short-term synaptic plasticity by affecting vesicle recruitment to the AZ. Finally, our study reveals a novel contribution of synapsin Ia to define the surface area of AZs.

  11. Synapsin Is Selectively Required for Anesthesia-Sensitive Memory

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    Knapek, Stephan; Gerber, Bertram; Tanimoto, Hiromu

    2010-01-01

    Odor-shock memory in "Drosophila melanogaster" consists of heterogeneous components each with different dynamics. We report that a null mutant for the evolutionarily conserved synaptic protein Synapsin entails a memory deficit selectively in early memory, leaving later memory as well as sensory motor function unaffected. Notably, a consolidated…

  12. Reduced alcohol consumption in mice lacking preprodynorphin.

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    Blednov, Yuri A; Walker, Danielle; Martinez, Marni; Harris, R Adron

    2006-10-01

    Many studies suggest a role for endogenous opioid peptides and their receptors in regulation of ethanol intake. It is commonly accepted that the kappa-opioid receptors and their endogenous ligands, dynorphins, produce a dysphoric state and therefore may be responsible for avoidance of alcohol. We used mutant mice lacking preprodynorphin in a variety of behavioral tests of alcohol actions. Null mutant female, but not male, mice showed significantly lower preference for alcohol and consumed lower amounts of alcohol in a two-bottle choice test as compared with wild-type littermates. In the same test, knockout mice of both sexes showed a strong reduction of preference for saccharin compared to control mice. In contrast, under conditions of limited (4 h) access (light phase of the light/dark cycle), null mutant mice did not show any differences in consumption of saccharin, but they showed significantly reduced intake of sucrose. To determine the possible cause for reduction of ethanol preference and intake, we studied other ethanol-related behaviors in mice lacking the preprodynorphin gene. There were no differences between null mutant and wild-type mice in ethanol-induced loss of righting reflex, acute ethanol withdrawal, ethanol-induced conditioned place preference, or conditioned taste aversion to ethanol. These results indicate that deletion of preprodynorphin leads to substantial reduction of alcohol intake in female mice, and suggest that this is caused by decreased orosensory reward of alcohol (sweet taste and/or palatability).

  13. Synapsin I (protein I) in different brain regions in senile dementia of Alzheimer type and in multiinfarct dementia

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    Adolfsson, R.; Alafuzoff, I.; Winblad, B.; Perdahl, E.; Albert, K.A.; Nestler, E.J.; Greengard, P.

    1984-01-01

    Synapsin I (Protein I), a neuron-specfic phosphoprotein enriched in presynaptic nerve terminals, has been used as a quantitative marker for the density of nerve terminals in five brain regions (caudate nucleus, cingulate gyrus, hippocampus, mesencephalon and putamen) from patients who had suffered from Alzheimer disease/senile dementia of Alzheimer type (AD/SDAT), from patients with multi-infarct dementia (MID), and from agematched controls. Samples were obtained at autopsy. Lower levels of Synapsin I were observed in the hippocampus of patients with AD/SDAT but not with MID. There were no significant differences in Synapsin I levels between patients and controls in any of the other four brain regions examined. (Author)

  14. Synapsin I (Protein I) in different brain regions in senile dementia of Alzheimer type and in multiinfarct dementia. [Radioimmunoassay

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    Adolfsson, R; Alafuzoff, I; Winblad, B [Umeaa Univ. (Sweden); Perdahl, E; Albert, K A; Nestler, E J; Greengard, P [Rockefeller Univ., New York (USA)

    1984-01-01

    Synapsin I (Protein I), a neuron-specfic phosphoprotein enriched in presynaptic nerve terminals, has been used as a quantitative marker for the density of nerve terminals in five brain regions (caudate nucleus, cingulate gyrus, hippocampus, mesencephalon and putamen) from patients who had suffered from Alzheimer disease/senile dementia of Alzheimer type (AD/SDAT), from patients with multi-infarct dementia (MID), and from agematched controls. Samples were obtained at autopsy. Lower levels of Synapsin I were observed in the hippocampus of patients with AD/SDAT but not with MID. There were no significant differences in Synapsin I levels between patients and controls in any of the other four brain regions examined.

  15. Better Targeting, Better Efficiency for Wide-scale Neuronal Transduction with the Synapsin Promoter and AAV-PHP.B

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    Kasey L Jackson

    2016-11-01

    Full Text Available Widespread genetic modification of cells in the central nervous system (CNS with a viral vector has become possible and increasingly more efficient. We previously applied an AAV9 vector with the cytomegalovirus/chicken beta-actin hybrid (CBA promoter and achieved wide-scale CNS transduction in neonatal and adult rats. However, this method transduces a variety of tissues in addition to the CNS. Thus we studied intravenous AAV9 gene transfer with a synapsin promoter to better target the neurons. We noted in systematic comparisons that the synapsin promoter drives lower level expression than does the CBA promoter. The engineered AAV-PHP.B serotype was compared with AAV9, and AAV-PHP.B did enhance the efficiency of expression. Combining the synapsin promoter with AAV-PHP.B could therefore be advantageous in terms of combining two refinements of targeting and efficiency. Wide-scale expression was used to model a disease with widespread pathology. Vectors encoding the amyotrophic lateral sclerosis (ALS-related protein TDP-43 with the synapsin promoter and AAV-PHP.B were used for efficient CNS-targeted TDP-43 expression. Intracerebroventricular injections were also explored to limit TDP-43 expression to the CNS. The neuron-selective promoter and the AAV-PHP.B enhanced gene transfer and ALS disease modeling in adult rats.

  16. Better Targeting, Better Efficiency for Wide-Scale Neuronal Transduction with the Synapsin Promoter and AAV-PHP.B.

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    Jackson, Kasey L; Dayton, Robert D; Deverman, Benjamin E; Klein, Ronald L

    2016-01-01

    Widespread genetic modification of cells in the central nervous system (CNS) with a viral vector has become possible and increasingly more efficient. We previously applied an AAV9 vector with the cytomegalovirus/chicken beta-actin (CBA) hybrid promoter and achieved wide-scale CNS transduction in neonatal and adult rats. However, this method transduces a variety of tissues in addition to the CNS. Thus we studied intravenous AAV9 gene transfer with a synapsin promoter to better target the neurons. We noted in systematic comparisons that the synapsin promoter drives lower level expression than does the CBA promoter. The engineered adeno-associated virus (AAV)-PHP.B serotype was compared with AAV9, and AAV-PHP.B did enhance the efficiency of expression. Combining the synapsin promoter with AAV-PHP.B could therefore be advantageous in terms of combining two refinements of targeting and efficiency. Wide-scale expression was used to model a disease with widespread pathology. Vectors encoding the amyotrophic lateral sclerosis (ALS)-related protein transactive response DNA-binding protein, 43 kDa (TDP-43) with the synapsin promoter and AAV-PHP.B were used for efficient CNS-targeted TDP-43 expression. Intracerebroventricular injections were also explored to limit TDP-43 expression to the CNS. The neuron-selective promoter and the AAV-PHP.B enhanced gene transfer and ALS disease modeling in adult rats.

  17. Effect of intravenous transplantation of bone marrow mesenchymal stem cells on neurotransmitters and synapsins in rats with spinal cord injury

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    Chen, Shaoqiang; Wu, Bilian; Lin, Jianhua

    2012-01-01

    Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3–5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time (1–5 weeks). Expressions of choline acetyltransferase, glutamic acid decarboxylase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury. PMID:25657678

  18. Hippocampal synapsin I, growth-associated protein-43, and microtubule-associated protein-2 immunoreactivity in learned helplessness rats and antidepressant-treated rats.

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    Iwata, M; Shirayama, Y; Ishida, H; Kawahara, R

    2006-09-01

    Learned helplessness rats are thought to be an animal model of depression. To study the role of synapse plasticity in depression, we examined the effects of learned helplessness and antidepressant treatments on synapsin I (a marker of presynaptic terminals), growth-associated protein-43 (GAP-43; a marker of growth cones), and microtubule-associated protein-2 (MAP-2; a marker of dendrites) in the hippocampus by immunolabeling. (1) Learned helplessness rats showed significant increases in the expression of synapsin I two days after the attainment of learned helplessness, and significant decreases in the protein expression eight days after the achievement of learned helplessness. Subchronic treatment of naïve rats with imipramine or fluvoxamine significantly decreased the expression of synapsin I. (2) Learned helplessness increased the expression of GAP-43 two days and eight days after learned helplessness training. Subchronic treatment of naïve rats with fluvoxamine but not imipramine showed a tendency to decrease the expression of synapsin I. (3) Learned helplessness rats showed increased expression of MAP-2 eight days after the attainment of learned helplessness. Naïve rats subchronically treated with imipramine showed a tendency toward increased expression of MAP-2, but those treated with fluvoxamine did not. These results indicate that the neuroplasticity-related proteins synapsin I, GAP-43, and MAP-2 may play a role in the pathophysiology of depression and the mechanisms of antidepressants.

  19. Lacking Ketohexokinase-A Exacerbates Renal Injury in Streptozotocin-induced Diabetic Mice.

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    Doke, Tomohito; Ishimoto, Takuji; Hayasaki, Takahiro; Ikeda, Satsuki; Hasebe, Masako; Hirayama, Akiyoshi; Soga, Tomoyoshi; Kato, Noritoshi; Kosugi, Tomoki; Tsuboi, Naotake; Lanaspa, Miguel A; Johnson, Richard J; Kadomatsu, Kenji; Maruyama, Shoichi

    2018-03-28

    Ketohexokinase (KHK), a primary enzyme in fructose metabolism, has two isoforms, namely, KHK-A and KHK-C. Previously, we reported that renal injury was reduced in streptozotocin-induced diabetic mice which lacked both isoforms. Although both isoforms express in kidney, it has not been elucidated whether each isoform plays distinct roles in the development of diabetic kidney disease (DKD). The aim of the study is to elucidate the role of KHK-A for DKD progression. Diabetes was induced by five consecutive daily intraperitoneal injections of streptozotocin (50 mg/kg) in C57BL/6 J wild-type mice, mice lacking KHK-A alone (KHK-A KO), and mice lacking both KHK-A and KHK-C (KHK-A/C KO). At 35 weeks, renal injury, inflammation, hypoxia, and oxidative stress were examined. Metabolomic analysis including polyol pathway, fructose metabolism, glycolysis, TCA (tricarboxylic acid) cycle, and NAD (nicotinamide adenine dinucleotide) metabolism in kidney and urine was done. Diabetic KHK-A KO mice developed severe renal injury compared to diabetic wild-type mice, and this was associated with further increases of intrarenal fructose, dihydroxyacetone phosphate (DHAP), TCA cycle intermediates levels, and severe inflammation. In contrast, renal injury was prevented in diabetic KHK-A/C KO mice compared to both wild-type and KHK-A KO diabetic mice. Further, diabetic KHK-A KO mice contained decreased renal NAD + level with the increase of renal hypoxia-inducible factor 1-alpha expression despite having increased renal nicotinamide (NAM) level. These results suggest that KHK-C might play a deleterious role in DKD progression through endogenous fructose metabolism, and that KHK-A plays a unique protective role against the development of DKD. Copyright © 2018. Published by Elsevier Inc.

  20. Motor hypertonia and lack of locomotor coordination in mutant mice lacking DSCAM.

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    Lemieux, Maxime; Laflamme, Olivier D; Thiry, Louise; Boulanger-Piette, Antoine; Frenette, Jérôme; Bretzner, Frédéric

    2016-03-01

    Down syndrome cell adherence molecule (DSCAM) contributes to the normal establishment and maintenance of neural circuits. Whereas there is abundant literature regarding the role of DSCAM in the neural patterning of the mammalian retina, less is known about motor circuits. Recently, DSCAM mutation has been shown to impair bilateral motor coordination during respiration, thus causing death at birth. DSCAM mutants that survive through adulthood display a lack of locomotor endurance and coordination in the rotarod test, thus suggesting that the DSCAM mutation impairs motor control. We investigated the motor and locomotor functions of DSCAM(2J) mutant mice through a combination of anatomical, kinematic, force, and electromyographic recordings. With respect to wild-type mice, DSCAM(2J) mice displayed a longer swing phase with a limb hyperflexion at the expense of a shorter stance phase during locomotion. Furthermore, electromyographic activity in the flexor and extensor muscles was increased and coactivated over 20% of the step cycle over a wide range of walking speeds. In contrast to wild-type mice, which used lateral walk and trot at walking speed, DSCAM(2J) mice used preferentially less coordinated gaits, such as out-of-phase walk and pace. The neuromuscular junction and the contractile properties of muscles, as well as their muscle spindles, were normal, and no signs of motor rigidity or spasticity were observed during passive limb movements. Our study demonstrates that the DSCAM mutation induces dystonic hypertonia and a disruption of locomotor gaits. Copyright © 2016 the American Physiological Society.

  1. Kidney failure in mice lacking the tetraspanin CD151

    NARCIS (Netherlands)

    Sachs, Norman; Kreft, Maaike; van den Bergh Weerman, Marius A.; Beynon, Andy J.; Peters, Theo A.; Weening, Jan J.; Sonnenberg, Arnoud

    2006-01-01

    The tetraspanin CD151 is a cell-surface molecule known for its strong lateral interaction with the laminin-binding integrin alpha3beta1. Patients with a nonsense mutation in CD151 display end-stage kidney failure associated with regional skin blistering and sensorineural deafness, and mice lacking

  2. Kidney failure in mice lacking the tetraspanin CD151.

    NARCIS (Netherlands)

    Sachs, N.; Kreft, M.; Bergh Weerman, M. van der; Beynon, A.J.; Peters, T.A.; Weening, J.J.; Sonnenberg, A.

    2006-01-01

    The tetraspanin CD151 is a cell-surface molecule known for its strong lateral interaction with the laminin-binding integrin alpha3beta1. Patients with a nonsense mutation in CD151 display end-stage kidney failure associated with regional skin blistering and sensorineural deafness, and mice lacking

  3. Myocardial mitochondrial and contractile function are preserved in mice lacking adiponectin.

    Directory of Open Access Journals (Sweden)

    Martin Braun

    Full Text Available Adiponectin deficiency leads to increased myocardial infarct size following ischemia reperfusion and to exaggerated cardiac hypertrophy following pressure overload, entities that are causally linked to mitochondrial dysfunction. In skeletal muscle, lack of adiponectin results in impaired mitochondrial function. Thus, it was our objective to investigate whether adiponectin deficiency impairs mitochondrial energetics in the heart. At 8 weeks of age, heart weight-to-body weight ratios were not different between adiponectin knockout (ADQ-/- mice and wildtypes (WT. In isolated working hearts, cardiac output, aortic developed pressure and cardiac power were preserved in ADQ-/- mice. Rates of fatty acid oxidation, glucose oxidation and glycolysis were unchanged between groups. While myocardial oxygen consumption was slightly reduced (-24% in ADQ-/- mice in isolated working hearts, rates of maximal ADP-stimulated mitochondrial oxygen consumption and ATP synthesis in saponin-permeabilized cardiac fibers were preserved in ADQ-/- mice with glutamate, pyruvate or palmitoyl-carnitine as a substrate. In addition, enzymatic activity of respiratory complexes I and II was unchanged between groups. Phosphorylation of AMP-activated protein kinase and SIRT1 activity were not decreased, expression and acetylation of PGC-1α were unchanged, and mitochondrial content of OXPHOS subunits was not decreased in ADQ-/- mice. Finally, increasing energy demands due to prolonged subcutaneous infusion of isoproterenol did not differentially affect cardiac contractility or mitochondrial function in ADQ-/- mice compared to WT. Thus, mitochondrial and contractile function are preserved in hearts of mice lacking adiponectin, suggesting that adiponectin may be expendable in the regulation of mitochondrial energetics and contractile function in the heart under non-pathological conditions.

  4. Nicotine anxiogenic and rewarding effects are decreased in mice lacking beta-endorphin.

    Science.gov (United States)

    Trigo, José M; Zimmer, Andreas; Maldonado, Rafael

    2009-06-01

    The endogenous opioid system plays an important role in the behavioral effects of nicotine. Thus, micro-opioid receptor and the endogenous opioids derived from proenkephalin are involved in the central effects of nicotine. However, the role played by the different endogenous opioid peptides in the acute and chronic effects of nicotine remains to be fully established. Mice lacking beta-endorphin were acutely injected with nicotine at different doses to evaluate locomotor, anxiogenic and antinociceptive responses. The rewarding properties of nicotine were evaluated by using the conditioned place-preference paradigm. Mice chronically treated with nicotine were acutely injected with mecamylamine to study the behavioral expression of nicotine withdrawal. Mice lacking beta-endorphin exhibited a spontaneous hypoalgesia and hyperlocomotion and a reduction on the anxiogenic and rewarding effects induced by nicotine. Nicotine induced similar antinociception and hypolocomotion in both genotypes and no differences were found in the development of physical dependence. The dissociation between nicotine rewarding properties and physical dependence suggests a differential implication of beta-endorphin in these addictive related responses.

  5. Nicotine anxiogenic and rewarding effects are decreased in mice lacking β-endorphin

    Science.gov (United States)

    Trigo, José M.; Zimmer, Andreas; Maldonado, Rafael

    2009-01-01

    The endogenous opioid system plays an important role in the behavioral effects of nicotine. Thus, μ-opioid receptor and the endogenous opioids derived from proenkephalin are involved in the central effects of nicotine. However, the role played by the different endogenous opioid peptides in the acute and chronic effects of nicotine remains to be fully established. Mice lacking β-endorphin were acutely injected with nicotine at different doses to evaluate locomotor, anxiogenic and antinociceptive responses. The rewarding properties of nicotine were evaluated by using the conditioned place-preference paradigm. Mice chronically treated with nicotine were acutely injected with mecamylamine to study the behavioral expression of nicotine withdrawal. Mice lacking β-endorphin exhibited a spontaneous hypoalgesia and hyperlocomotion and a reduction on the anxiogenic and rewarding effects induced by nicotine. Nicotine induced similar antinociception and hypolocomotion in both genotypes and no differences were found in the development of physical dependence. The dissociation between nicotine rewarding properties and physical dependence suggests a differential implication of β-endorphin in these addictive related responses. PMID:19376143

  6. Mice lacking inositol 1,4,5-trisphosphate receptors exhibit dry eye.

    Directory of Open Access Journals (Sweden)

    Takaaki Inaba

    Full Text Available Tear secretion is important as it supplies water to the ocular surface and keeps eyes moist. Both the parasympathetic and sympathetic pathways contribute to tear secretion. Although intracellular Ca2+ elevation in the acinar cells of lacrimal glands is a crucial event for tear secretion in both the pathways, the Ca2+ channel, which is responsible for the Ca2+ elevation in the sympathetic pathway, has not been sufficiently analyzed. In this study, we examined tear secretion in mice lacking the inositol 1,4,5-trisphosphate receptor (IP3R types 2 and 3 (Itpr2-/-;Itpr3-/-double-knockout mice. We found that tear secretion in both the parasympathetic and sympathetic pathways was abolished in Itpr2-/-;Itpr3-/- mice. Intracellular Ca2+ elevation in lacrimal acinar cells after acetylcholine and epinephrine stimulation was abolished in Itpr2-/-;Itpr3-/- mice. Consequently, Itpr2-/-;Itpr3-/- mice exhibited keratoconjunctival alteration and corneal epithelial barrier disruption. Inflammatory cell infiltration into the lacrimal glands and elevation of serum autoantibodies, a representative marker for Sjögren's syndrome (SS in humans, were also detected in older Itpr2-/-;Itpr3-/- mice. These results suggested that IP3Rs are essential for tear secretion in both parasympathetic and sympathetic pathways and that Itpr2-/-;Itpr3-/- mice could be a new dry eye mouse model with symptoms that mimic those of SS.

  7. Ethanol-related behaviors in mice lacking the sigma-1 receptor.

    Science.gov (United States)

    Valenza, Marta; DiLeo, Alyssa; Steardo, Luca; Cottone, Pietro; Sabino, Valentina

    2016-01-15

    The Sigma-1 receptor (Sig-1R) is a chaperone protein that has been implicated in drug abuse and addiction. Multiple studies have characterized the role the Sig-1R plays in psychostimulant addiction; however, fewer studies have specifically investigated its role in alcohol addiction. We have previously shown that antagonism of the Sig-1R reduces excessive drinking and motivation to drink, whereas agonism induces binge-like drinking in rodents. The objectives of these studies were to investigate the impact of Sig-1R gene deletion in C57Bl/6J mice on ethanol drinking and other ethanol-related behaviors. We used an extensive panel of behavioral tests to examine ethanol actions in male, adult mice lacking Oprs1, the gene encoding the Sig-1R. To compare ethanol drinking behavior, Sig-1 knockout (KO) and wild type (WT) mice were subject to a two-bottle choice, continuous access paradigm with different concentrations of ethanol (3-20% v/v) vs. water. Consumption of sweet and bitter solutions was also assessed in Sig-1R KO and WT mice. Finally, motor stimulant sensitivity, taste aversion and ataxic effects of ethanol were assessed. Sig-1R KO mice displayed higher ethanol intake compared to WT mice; the two genotypes did not differ in their sweet or bitter taste perception. Sig-1R KO mice showed lower sensitivity to ethanol stimulant effects, but greater sensitivity to its taste aversive effects. Ethanol-induced sedation was instead unaltered in the mutants. Our results prove that the deletion of the Sig-1R increases ethanol consumption, likely by decreasing its rewarding effects, and therefore indicating that the Sig-1R is involved in modulation of the reinforcing effects of alcohol. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Mice lacking liver-specific β-catenin develop steatohepatitis and fibrosis after iron overload.

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    Preziosi, Morgan E; Singh, Sucha; Valore, Erika V; Jung, Grace; Popovic, Branimir; Poddar, Minakshi; Nagarajan, Shanmugam; Ganz, Tomas; Monga, Satdarshan P

    2017-08-01

    Iron overload disorders such as hereditary hemochromatosis and iron loading anemias are a common cause of morbidity from liver diseases and increase risk of hepatic fibrosis and hepatocellular carcinoma (HCC). Treatment options for iron-induced damage are limited, partly because there is lack of animal models of human disease. Therefore, we investigated the effect of iron overload in liver-specific β-catenin knockout mice (KO), which are susceptible to injury, fibrosis and tumorigenesis following chemical carcinogen exposure. Iron overload diet was administered to KO and littermate control (CON) mice for various times. To ameliorate an oxidant-mediated component of tissue injury, N-Acetyl-L-(+)-cysteine (NAC) was added to drinking water of mice on iron overload diet. KO on iron diet (KO +Fe) exhibited remarkable inflammation, followed by steatosis, oxidative stress, fibrosis, regenerating nodules and occurrence of occasional HCC. Increased injury in KO +Fe was associated with activated protein kinase B (AKT), ERK, and NF-κB, along with reappearance of β-catenin and target gene Cyp2e1, which promoted lipid peroxidation and hepatic damage. Addition of NAC to drinking water protected KO +Fe from hepatic steatosis, injury and fibrosis, and prevented activation of AKT, ERK, NF-κB and reappearance of β-catenin. The absence of hepatic β-catenin predisposes mice to hepatic injury and fibrosis following iron overload, which was reminiscent of hemochromatosis and associated with enhanced steatohepatitis and fibrosis. Disease progression was notably alleviated by antioxidant therapy, which supports its chemopreventive role in the management of chronic iron overload disorders. Lack of animal models for iron overload disorders makes it hard to study the disease process for improving therapies. Feeding high iron diet to mice that lack the β-catenin gene in liver cells led to increased inflammation followed by fat accumulation, cell death and wound healing that mimicked

  9. Impaired intestinal proglucagon processing in mice lacking prohormone convertase 1

    DEFF Research Database (Denmark)

    Ugleholdt, Randi; Zhu, Xiaorong; Deacon, Carolyn F

    2003-01-01

    proglucagon processing showed marked defects. Tissue proglucagon levels in null mice were elevated, and proglucagon processing to glicentin, oxyntomodulin, and glucagon-like peptide-1 and -2 (GLP-1 and GLP-2) was markedly decreased, indicating that PC1 is essential for the processing of all the intestinal...... proglucagon cleavage sites. This includes the monobasic site R(77) and, thereby, production of mature, biologically active GLP-1. We also found elevated glucagon levels, suggesting that factors other than PC1 that are capable of processing to mature glucagon are present in the secretory granules of the L cell......The neuroendocrine prohormone convertases 1 and 2 (PC1 and PC2) are expressed in endocrine intestinal L cells and pancreatic A cells, respectively, and colocalize with proglucagon in secretory granules. Mice lacking PC2 have multiple endocrinopathies and cannot process proglucagon to mature...

  10. Mutant Mice Lacking the p53 C-Terminal Domain Model Telomere Syndromes

    NARCIS (Netherlands)

    Simeonova, I.; Jaber, S.; Draskovic, I.; Bardot, B.; Fang, M.; Bouarich-Bourimi, R.; Lejour, V.; Charbonnier, L.; Soudais, C.; Bourdon, J.C.; Huerre, M.; Londono-Vallejo, A.; Toledo, F.

    2013-01-01

    Mutations in p53, although frequent in human cancers, have not been implicated in telomere-related syndromes. Here, we show that homozygous mutant mice expressing p53(Delta31), a p53 lacking the C-terminal domain, exhibit increased p53 activity and suffer from aplastic anemia and pulmonary fibrosis,

  11. Mice lacking hippocampal left-right asymmetry show non-spatial learning deficits.

    Science.gov (United States)

    Shimbo, Akihiro; Kosaki, Yutaka; Ito, Isao; Watanabe, Shigeru

    2018-01-15

    Left-right asymmetry is known to exist at several anatomical levels in the brain and recent studies have provided further evidence to show that it also exists at a molecular level in the hippocampal CA3-CA1 circuit. The distribution of N-methyl-d-aspartate (NMDA) receptor NR2B subunits in the apical and basal synapses of CA1 pyramidal neurons is asymmetrical if the input arrives from the left or right CA3 pyramidal neurons. In the present study, we examined the role of hippocampal asymmetry in cognitive function using β2-microglobulin knock-out (β2m KO) mice, which lack hippocampal asymmetry. We tested β2m KO mice in a series of spatial and non-spatial learning tasks and compared the performances of β2m KO and C57BL6/J wild-type (WT) mice. The β2m KO mice appeared normal in both spatial reference memory and spatial working memory tasks but they took more time than WT mice in learning the two non-spatial learning tasks (i.e., a differential reinforcement of lower rates of behavior (DRL) task and a straight runway task). The β2m KO mice also showed less precision in their response timing in the DRL task and showed weaker spontaneous recovery during extinction in the straight runway task. These results indicate that hippocampal asymmetry is important for certain characteristics of non-spatial learning. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Regulation of ENaC in mice lacking renal insulin receptors in the collecting duct

    Science.gov (United States)

    Pavlov, Tengis S.; Ilatovskaya, Daria V.; Levchenko, Vladislav; Li, Lijun; Ecelbarger, Carolyn M.; Staruschenko, Alexander

    2013-01-01

    The epithelial sodium channel (ENaC) is one of the central effectors involved in regulation of salt and water homeostasis in the kidney. To study mechanisms of ENaC regulation, we generated knockout mice lacking the insulin receptor (InsR KO) specifically in the collecting duct principal cells. Single-channel analysis in freshly isolated split-open tubules demonstrated that the InsR-KO mice have significantly lower ENaC activity compared to their wild-type (C57BL/6J) littermates when animals were fed either normal or sodium-deficient diets. Immunohistochemical and Western blot assays demonstrated no significant changes in expression of ENaC subunits in InsR-KO mice compared to wild-type littermates. Insulin treatment caused greater ENaC activity in split-open tubules isolated from wild-type mice but did not have this effect in the InsR-KO mice. Thus, these results suggest that insulin increases ENaC activity via its own receptor affecting the channel open probability. To further determine the mechanism of the action of insulin on ENaC, we used mouse mpkCCDc14 principal cells. Insulin significantly augmented amiloride-sensitive transepithelial flux in these cells. Pretreatment of the mpkCCDc14 cells with phosphatidylinositol 3-kinase (LY294002; 10 μM) or mTOR (PP242; 100 nM) inhibitors precluded this effect. This study provides new information about the importance of insulin receptors expressed in collecting duct principal cells for ENaC activity.—Pavlov, T. S., Ilatovskaya, D. V., Levchenko, V., Li, L., Ecelbarger, C. M., Staruschenko, A. Regulation of ENaC in mice lacking renal insulin receptors in the collecting duct. PMID:23558339

  13. Selective reward deficit in mice lacking beta-endorphin and enkephalin.

    Science.gov (United States)

    Hayward, Michael D; Pintar, John E; Low, Malcolm J

    2002-09-15

    It has been impossible to unequivocally identify which endogenous opioids modulate the incentive value of rewarding stimuli because these peptides are not highly selective for any single opioid receptor subtype. Here, we present evidence based on the measurement of instrumental behavior of beta-endorphin and enkephalin knock-out mice that both opioid peptides play a positive role. A progressive ratio schedule was used to measure how hard an animal would work for food reinforcers. The loss of either opioid reduced responding under this schedule, regardless of the palatability of the three different formulas of reinforcers used. The phenotype of mice lacking both endogenous opioids was nearly identical to the phenotype of mice mutant for either individual opioid. Responses were tested in nondeprived and deprived feeding states but were reduced in beta-endorphin- and enkephalin-deficient mice only when they were maintained under nondeprived conditions. Other operant manipulations ruled out variables that might contribute nonspecifically to this result such as differences in acquisition, early satiation, motor performance deficit, and reduced resistance to extinction. In contrast to the effects on instrumental performance, the loss of either or both endogenous opioids did not influence preference for water flavored with sucrose or saccharin in a two-bottle free-choice drinking paradigm. We conclude that both beta-endorphin and enkephalin positively contribute to the incentive-motivation to acquire food reinforcers. Because the attenuation of operant responding was observed only during a nondeprived motivational state, the hedonics of feeding are likely altered rather than energy homeostasis.

  14. Multiple sleep alterations in mice lacking cannabinoid type 1 receptors.

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    Alessandro Silvani

    Full Text Available Cannabinoid type 1 (CB1 receptors are highly expressed in the brain and play a role in behavior control. Endogenous cannabinoid signaling is modulated by high-fat diet (HFD. We investigated the consequences of congenital lack of CB1 receptors on sleep in mice fed standard diet (SD and HFD. CB1 cannabinoid receptor knock-out (KO and wild-type (WT mice were fed SD or HFD for 4 months (n = 9-10 per group. Mice were instrumented with electroencephalographic (EEG and electromyographic electrodes. Recordings were performed during baseline (48 hours, sleep deprivation (gentle handling, 6 hours, sleep recovery (18 hours, and after cage switch (insomnia model paradigm, 6 hours. We found multiple significant effects of genotype on sleep. In particular, KO spent more time awake and less time in non-rapid-eye-movement sleep (NREMS and rapid-eye-movement sleep (REMS than WT during the dark (active period but not during the light (rest period, enhancing the day-night variation of wake-sleep amounts. KO had slower EEG theta rhythm during REMS. REMS homeostasis after sleep deprivation was less effective in KO than in WT. Finally, KO habituated more rapidly to the arousing effect of the cage-switch test than WT. We did not find any significant effects of diet or of diet x genotype interaction on sleep. The occurrence of multiple sleep alterations in KO indicates important roles of CB1 cannabinoid receptors in limiting arousal during the active period of the day, in sleep regulation, and in sleep EEG in mice.

  15. Platelet activating factor enhances synaptic vesicle exocytosis via PKC, elevated intracellular calcium, and modulation of synapsin 1 dynamics and phosphorylation

    Directory of Open Access Journals (Sweden)

    Jennetta W Hammond

    2016-01-01

    Full Text Available Platelet activating factor (PAF is an inflammatory phospholipid signaling molecule implicated in synaptic plasticity, learning and memory and neurotoxicity during neuroinflammation. However, little is known about the intracellular mechanisms mediating PAF’s physiological or pathological effects on synaptic facilitation. We show here that PAF receptors are localized at the synapse. Using fluorescent reporters of presynaptic activity we show that a non-hydrolysable analogue of PAF (cPAF enhances synaptic vesicle release from individual presynaptic boutons by increasing the size or release of the readily releasable pool and the exocytosis rate of the total recycling pool. cPAF also activates previously silent boutons resulting in vesicle release from a larger number of terminals. The underlying mechanism involves elevated calcium within presynaptic boutons and protein kinase C (PKC activation. Furthermore, cPAF increases synapsin I phosphorylation at sites 1 and 3, and increases dispersion of synapsin I from the presynaptic compartment during stimulation, freeing synaptic vesicles for subsequent release. These findings provide a conceptual framework for how PAF, regardless of its cellular origin, can modulate synapses during normal and pathologic synaptic activity.

  16. Lack of phosphatidylethanolamine N-methyltransferase in mice does not promote fatty acid oxidation in skeletal muscle.

    Science.gov (United States)

    Tasseva, Guergana; van der Veen, Jelske N; Lingrell, Susanne; Jacobs, René L; Vance, Dennis E; Vance, Jean E

    2016-02-01

    Phosphatidylethanolamine N-methyltransferase (PEMT) converts phosphatidylethanolamine (PE) to phosphatidylcholine (PC) in the liver. Mice lacking PEMT are protected from high-fat diet-induced obesity and insulin resistance, and exhibit increased whole-body energy expenditure and oxygen consumption. Since skeletal muscle is a major site of fatty acid oxidation and energy utilization, we determined if rates of fatty acid oxidation/oxygen consumption in muscle are higher in Pemt(-/-) mice than in Pemt(+/+) mice. Although PEMT is abundant in the liver, PEMT protein and activity were undetectable in four types of skeletal muscle. Moreover, amounts of PC and PE in the skeletal muscle were not altered by PEMT deficiency. Thus, we concluded that any influence of PEMT deficiency on skeletal muscle would be an indirect consequence of lack of PEMT in liver. Neither the in vivo rate of fatty acid uptake by muscle nor the rate of fatty acid oxidation in muscle explants and cultured myocytes depended upon Pemt genotype. Nor did PEMT deficiency increase oxygen consumption or respiratory function in skeletal muscle mitochondria. Thus, the increased whole body oxygen consumption in Pemt(-/-) mice, and resistance of these mice to diet-induced weight gain, are not primarily due to increased capacity of skeletal muscle for utilization of fatty acids as an energy source. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  17. Lack of liver glycogen causes hepatic insulin resistance and steatosis in mice.

    Science.gov (United States)

    Irimia, Jose M; Meyer, Catalina M; Segvich, Dyann M; Surendran, Sneha; DePaoli-Roach, Anna A; Morral, Nuria; Roach, Peter J

    2017-06-23

    Disruption of the Gys2 gene encoding the liver isoform of glycogen synthase generates a mouse strain (LGSKO) that almost completely lacks hepatic glycogen, has impaired glucose disposal, and is pre-disposed to entering the fasted state. This study investigated how the lack of liver glycogen increases fat accumulation and the development of liver insulin resistance. Insulin signaling in LGSKO mice was reduced in liver, but not muscle, suggesting an organ-specific defect. Phosphorylation of components of the hepatic insulin-signaling pathway, namely IRS1, Akt, and GSK3, was decreased in LGSKO mice. Moreover, insulin stimulation of their phosphorylation was significantly suppressed, both temporally and in an insulin dose response. Phosphorylation of the insulin-regulated transcription factor FoxO1 was somewhat reduced and insulin treatment did not elicit normal translocation of FoxO1 out of the nucleus. Fat overaccumulated in LGSKO livers, showing an aberrant distribution in the acinus, an increase not explained by a reduction in hepatic triglyceride export. Rather, when administered orally to fasted mice, glucose was directed toward hepatic lipogenesis as judged by the activity, protein levels, and expression of several fatty acid synthesis genes, namely, acetyl-CoA carboxylase, fatty acid synthase, SREBP1c, chREBP, glucokinase, and pyruvate kinase. Furthermore, using cultured primary hepatocytes, we found that lipogenesis was increased by 40% in LGSKO cells compared with controls. Of note, the hepatic insulin resistance was not associated with increased levels of pro-inflammatory markers. Our results suggest that loss of liver glycogen synthesis diverts glucose toward fat synthesis, correlating with impaired hepatic insulin signaling and glucose disposal. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Impaired Glucose Metabolism in Mice Lacking the Tas1r3 Taste Receptor Gene.

    Science.gov (United States)

    Murovets, Vladimir O; Bachmanov, Alexander A; Zolotarev, Vasiliy A

    2015-01-01

    The G-protein-coupled sweet taste receptor dimer T1R2/T1R3 is expressed in taste bud cells in the oral cavity. In recent years, its involvement in membrane glucose sensing was discovered in endocrine cells regulating glucose homeostasis. We investigated importance of extraorally expressed T1R3 taste receptor protein in age-dependent control of blood glucose homeostasis in vivo, using nonfasted mice with a targeted mutation of the Tas1r3 gene that encodes the T1R3 protein. Glucose and insulin tolerance tests, as well as behavioral tests measuring taste responses to sucrose solutions, were performed with C57BL/6ByJ (Tas1r3+/+) inbred mice bearing the wild-type allele and C57BL/6J-Tas1r3tm1Rfm mice lacking the entire Tas1r3 coding region and devoid of the T1R3 protein (Tas1r3-/-). Compared with Tas1r3+/+ mice, Tas1r3-/- mice lacked attraction to sucrose in brief-access licking tests, had diminished taste preferences for sucrose solutions in the two-bottle tests, and had reduced insulin sensitivity and tolerance to glucose administered intraperitoneally or intragastrically, which suggests that these effects are due to absence of T1R3. Impairment of glucose clearance in Tas1r3-/- mice was exacerbated with age after intraperitoneal but not intragastric administration of glucose, pointing to a compensatory role of extraoral T1R3-dependent mechanisms in offsetting age-dependent decline in regulation of glucose homeostasis. Incretin effects were similar in Tas1r3+/+ and Tas1r3-/- mice, which suggests that control of blood glucose clearance is associated with effects of extraoral T1R3 in tissues other than the gastrointestinal tract. Collectively, the obtained data demonstrate that the T1R3 receptor protein plays an important role in control of glucose homeostasis not only by regulating sugar intake but also via its extraoral function, probably in the pancreas and brain.

  19. Impaired Glucose Metabolism in Mice Lacking the Tas1r3 Taste Receptor Gene.

    Directory of Open Access Journals (Sweden)

    Vladimir O Murovets

    Full Text Available The G-protein-coupled sweet taste receptor dimer T1R2/T1R3 is expressed in taste bud cells in the oral cavity. In recent years, its involvement in membrane glucose sensing was discovered in endocrine cells regulating glucose homeostasis. We investigated importance of extraorally expressed T1R3 taste receptor protein in age-dependent control of blood glucose homeostasis in vivo, using nonfasted mice with a targeted mutation of the Tas1r3 gene that encodes the T1R3 protein. Glucose and insulin tolerance tests, as well as behavioral tests measuring taste responses to sucrose solutions, were performed with C57BL/6ByJ (Tas1r3+/+ inbred mice bearing the wild-type allele and C57BL/6J-Tas1r3tm1Rfm mice lacking the entire Tas1r3 coding region and devoid of the T1R3 protein (Tas1r3-/-. Compared with Tas1r3+/+ mice, Tas1r3-/- mice lacked attraction to sucrose in brief-access licking tests, had diminished taste preferences for sucrose solutions in the two-bottle tests, and had reduced insulin sensitivity and tolerance to glucose administered intraperitoneally or intragastrically, which suggests that these effects are due to absence of T1R3. Impairment of glucose clearance in Tas1r3-/- mice was exacerbated with age after intraperitoneal but not intragastric administration of glucose, pointing to a compensatory role of extraoral T1R3-dependent mechanisms in offsetting age-dependent decline in regulation of glucose homeostasis. Incretin effects were similar in Tas1r3+/+ and Tas1r3-/- mice, which suggests that control of blood glucose clearance is associated with effects of extraoral T1R3 in tissues other than the gastrointestinal tract. Collectively, the obtained data demonstrate that the T1R3 receptor protein plays an important role in control of glucose homeostasis not only by regulating sugar intake but also via its extraoral function, probably in the pancreas and brain.

  20. Mutant Mice Lacking the p53 C-Terminal Domain Model Telomere Syndromes

    Directory of Open Access Journals (Sweden)

    Iva Simeonova

    2013-06-01

    Full Text Available Mutations in p53, although frequent in human cancers, have not been implicated in telomere-related syndromes. Here, we show that homozygous mutant mice expressing p53Δ31, a p53 lacking the C-terminal domain, exhibit increased p53 activity and suffer from aplastic anemia and pulmonary fibrosis, hallmarks of syndromes caused by short telomeres. Indeed, p53Δ31/Δ31 mice had short telomeres and other phenotypic traits associated with the telomere disease dyskeratosis congenita and its severe variant the Hoyeraal-Hreidarsson syndrome. Heterozygous p53+/Δ31 mice were only mildly affected, but decreased levels of Mdm4, a negative regulator of p53, led to a dramatic aggravation of their symptoms. Importantly, several genes involved in telomere metabolism were downregulated in p53Δ31/Δ31 cells, including Dyskerin, Rtel1, and Tinf2, which are mutated in dyskeratosis congenita, and Terf1, which is implicated in aplastic anemia. Together, these data reveal that a truncating mutation can activate p53 and that p53 plays a major role in the regulation of telomere metabolism.

  1. AAV9-mediated central nervous system–targeted gene delivery via cisterna magna route in mice

    Directory of Open Access Journals (Sweden)

    Vera Lukashchuk

    2016-01-01

    Full Text Available Current barriers to the use of adeno-associated virus serotype 9 (AAV9 in clinical trials for treating neurological disorders are its high expression in many off-target tissues such as liver and heart, and lack of cell specificity within the central nervous system (CNS when using ubiquitous promoters such as human cytomegalovirus (CMV or chicken-β-actin hybrid (CAG. To enhance targeting the transgene expression in CNS cells, self-complementary (sc AAV9 vectors, scAAV9-GFP vectors carrying neuronal Hb9 and synapsin 1, and nonspecific CMV and CAG promoters were constructed. We demonstrate that synapsin 1 and Hb9 promoters exclusively targeted neurons in vitro, although their strengths were up to 10-fold lower than that of CMV. In vivo analyses of mouse tissue after scAAV9-GFP vector delivery via the cisterna magna revealed a significant advantage of synapsin 1 promoter over both Hb9 variants in targeting neurons throughout the brain, since Hb9 promoters were driving gene expression mainly within the motor-related areas of the brain stem. In summary, this study demonstrates that cisterna magna administration is a safe alternative to intracranial or intracerebroventricular vector delivery route using scAAV9, and introduces a novel utility of the Hb9 promoter for the targeted gene expression for both in vivo and in vitro applications.

  2. Increased consumption of ethanol and sugar water in mice lacking the dopamine D2 long receptor.

    Science.gov (United States)

    Bulwa, Zachary B; Sharlin, Jordan A; Clark, Peter J; Bhattacharya, Tushar K; Kilby, Chessa N; Wang, Yanyan; Rhodes, Justin S

    2011-11-01

    Individual differences in dopamine D2 receptor (D2R) expression in the brain are thought to influence motivation and reinforcement for ethanol and other rewards. D2R exists in two isoforms, D2 long (D2LR) and D2 short (D2SR), produced by alternative splicing of the same gene. The relative contributions of D2LR versus D2SR to ethanol and sugar water drinking are not known. Genetic engineering was used to produce a line of knockout (KO) mice that lack D2LR and consequently have increased expression of D2SR. KO and wild-type (WT) mice of both sexes were tested for intake of 20% ethanol, 10% sugar water and plain tap water using established drinking-in-the-dark procedures. Mice were also tested for effects of the D2 antagonist eticlopride on intake of ethanol to determine whether KO responses were caused by lack of D2LR or overrepresentation of D2SR. Locomotor activity on running wheels and in cages without wheels was also measured for comparison. D2L KO mice drank significantly more ethanol than WT in both sexes. KO mice drank more sugar water than WT in females but not in males. Eticlopride dose dependently decreased ethanol intake in all groups except male KO. KO mice were less physically active than WT in cages with or without running wheels. Results suggest that overrepresentation of D2SR contributes to increased intake of ethanol in the KO mice. Decreasing wheel running and general levels of physical activity in the KO mice rules out the possibility that higher intake results from higher motor activity. Results extend the literature implicating altered expression of D2R in risk for addiction by delineating the contribution of individual D2R isoforms. These findings suggest that D2LR and D2SR play differential roles in consumption of alcohol and sugar rewards. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Mice lacking the p43 mitochondrial T3 receptor become glucose intolerant and insulin resistant during aging.

    Directory of Open Access Journals (Sweden)

    Christelle Bertrand

    Full Text Available Thyroid hormones (TH play an important regulatory role in energy expenditure regulation and are key regulators of mitochondrial activity. We have previously identified a mitochondrial triiodothyronine (T3 receptor (p43 which acts as a mitochondrial transcription factor of the organelle genome, which leads in vitro and in vivo, to a stimulation of mitochondrial biogenesis. Recently, we generated mice carrying a specific p43 invalidation. At 2 months of age, we reported that p43 depletion in mice induced a major defect in insulin secretion both in vivo and in isolated pancreatic islets, and a loss of glucose-stimulated insulin secretion. The present study was designed to determine whether p43 invalidation influences life expectancy and modulates blood glucose and insulin levels as well as glucose tolerance or insulin sensitivity during aging. We report that from 4 months old onwards, mice lacking p43 are leaner than wild-type mice. p43-/- mice also have a moderate reduction of life expectancy compared to wild type. We found no difference in blood glucose levels, excepted at 24 months old where p43-/- mice showed a strong hyperglycemia in fasting conditions compared to controls animals. However, the loss of glucose-stimulated insulin secretion was maintained whatever the age of mice lacking p43. If up to 12 months old, glucose tolerance remained unchanged, beyond this age p43-/- mice became increasingly glucose intolerant. In addition, if up to 12 months old p43 deficient animals were more sensitive to insulin, after this age we observed a loss of this capacity, culminating in 24 months old mice with a decreased sensitivity to the hormone. In conclusion, we demonstrated that during aging the depletion of the mitochondrial T3 receptor p43 in mice progressively induced an increased glycemia in the fasted state, glucose intolerance and an insulin-resistance several features of type-2 diabetes.

  4. DNA vaccination with a plasmid encoding LACK-TSA fusion against Leishmania major infection in BALB/c mice.

    Science.gov (United States)

    Maspi, N; Ghaffarifar, F; Sharifi, Z; Dalimi, A; Khademi, S Z

    2017-12-01

    Vaccination would be the most important strategy for the prevention and elimination of leishmaniasis. The aim of the present study was to compare the immune responses induced following DNA vaccination with LACK (Leishmania analogue of the receptor kinase C), TSA (Thiol-specific-antioxidant) genes alone or LACK-TSA fusion against cutaneous leishmaniasis (CL). Cellular and humoral immune responses were evaluated before and after challenge with Leishmania major (L. major). In addition, the mean lesion size was also measured from 3th week post-infection. All immunized mice showed a partial immunity characterized by higher interferon (IFN)-γ and Immunoglobulin G (IgG2a) levels compared to control groups (pTSA fusion. Mean lesion sizes reduced significantly in all immunized mice compared with control groups at 7th week post-infection (pTSA and TSA groups than LACK group after challenge (pTSA antigens against CL. Furthermore, this study demonstrated that a bivalent vaccine can induce stronger immune responses and protection against infectious challenge with L. major.

  5. Lack of Melanopsin Is Associated with Extreme Weight Loss in Mice upon Dietary Challenge.

    Directory of Open Access Journals (Sweden)

    Didem Göz Aytürk

    Full Text Available Metabolic disorders have been established as major risk factors for ocular complications and poor vision. However, little is known about the inverse possibility that ocular disease may cause metabolic dysfunction. To test this hypothesis, we assessed the metabolic consequences of a robust dietary challenge in several mouse models suffering from retinal mutations. To this end, mice null for melanopsin (Opn4-/-, the photopigment of intrinsically photosensitive retinal ganglion cells (ipRGCs, were subjected to five weeks of a ketogenic diet. These mice lost significantly more weight than wild-type controls or mice lacking rod and cone photoreceptors (Pde6brd1/rd1. Although ipRGCs are critical for proper circadian entrainment, and circadian misalignment has been implicated in metabolic pathology, we observed no differences in entrainment between Opn4-/- and control mice. Additionally, we observed no differences in any tested metabolic parameter between these mouse strains. Further studies are required to establish the mechanism giving rise to this dramatic phenotype observed in melanopsin-null mice. We conclude that the causality between ocular disease and metabolic disorders merits further investigation due to the popularity of diets that rely on the induction of a ketogenic state. Our study is a first step toward understanding retinal pathology as a potential cause of metabolic dysfunction.

  6. Impaired cutaneous wound healing in mice lacking tetranectin

    DEFF Research Database (Denmark)

    Iba, Kousuke; Hatakeyama, Naoko; Kojima, Takashi

    2009-01-01

    disruption of the tetranectin gene to elucidate the biological function of tetranectin. In this study, we showed that wound healing was markedly delayed in tetranectin-null mice compared with wild-type mice. A single full-thickness incision was made in the dorsal skin. By 14 days after the incision......, the wounds fully healed in all wild-type mice based on the macroscopic closure; in contrast, the progress of wound healing in the tetranectin null mice appeared to be impaired. In histological analysis, wounds of wild-type mice showed complete reepithelialization and healed by 14 days after the incision....... However, those of tetranectin-null mice never showed complete reepithelialization at 14 days. At 21 days after the injury, the wound healed and was covered with an epidermis. These results supported the fact that tetranectin may play a role in the wound healing process....

  7. Lack of the Lysosomal Membrane Protein, GLMP, in Mice Results in Metabolic Dysregulation in Liver.

    Directory of Open Access Journals (Sweden)

    Xiang Yi Kong

    Full Text Available Ablation of glycosylated lysosomal membrane protein (GLMP, formerly known as NCU-G1 has been shown to cause chronic liver injury which progresses into liver fibrosis in mice. Both lysosomal dysfunction and chronic liver injury can cause metabolic dysregulation. Glmp gt/gt mice (formerly known as Ncu-g1gt/gt mice were studied between 3 weeks and 9 months of age. Body weight gain and feed efficiency of Glmp gt/gt mice were comparable to wild type siblings, only at the age of 9 months the Glmp gt/gt siblings had significantly reduced body weight. Reduced size of epididymal fat pads was accompanied by hepatosplenomegaly in Glmp gt/gt mice. Blood analysis revealed reduced levels of blood glucose, circulating triacylglycerol and non-esterified fatty acids in Glmp gt/gt mice. Increased flux of glucose, increased de novo lipogenesis and lipid accumulation were detected in Glmp gt/gt primary hepatocytes, as well as elevated triacylglycerol levels in Glmp gt/gt liver homogenates, compared to hepatocytes and liver from wild type mice. Gene expression analysis showed an increased expression of genes involved in fatty acid uptake and lipogenesis in Glmp gt/gt liver compared to wild type. Our findings are in agreement with the metabolic alterations observed in other mouse models lacking lysosomal proteins, and with alterations characteristic for advanced chronic liver injury.

  8. Nonobese Diabetic (NOD Mice Lack a Protective B-Cell Response against the “Nonlethal” Plasmodium yoelii 17XNL Malaria Protozoan

    Directory of Open Access Journals (Sweden)

    Mirian Mendoza

    2016-01-01

    Full Text Available Background. Plasmodium yoelii 17XNL is a nonlethal malaria strain in mice of different genetic backgrounds including the C57BL/6 mice (I-Ab/I-Enull used in this study as a control strain. We have compared the trends of blood stage infection with the nonlethal murine strain of P. yoelii 17XNL malaria protozoan in immunocompetent Nonobese Diabetic (NOD mice prone to type 1 diabetes (T1D and C57BL/6 mice (control mice that are not prone to T1D and self-cure the P. yoelii 17XNL infection. Prediabetic NOD mice could not mount a protective antibody response to the P. yoelii 17XNL-infected red blood cells (iRBCs, and they all succumbed shortly after infection. Our data suggest that the lack of anti-P. yoelii 17XNL-iRBCs protective antibodies in NOD mice is a result of parasite-induced, Foxp3+ T regulatory (Treg cells able to suppress the parasite-specific antibody secretion. Conclusions. The NOD mouse model may help in identifying new mechanisms of B-cell evasion by malaria parasites. It may also serve as a more accurate tool for testing antimalaria therapeutics due to the lack of interference with a preexistent self-curing mechanism present in other mouse strains.

  9. Lack of bcr and abr promotes hypoxia-induced pulmonary hypertension in mice.

    Directory of Open Access Journals (Sweden)

    Min Yu

    Full Text Available Bcr and Abr are GTPase activating proteins that specifically downregulate activity of the small GTPase Rac in restricted cell types in vivo. Rac1 is expressed in smooth muscle cells, a critical cell type involved in the pathogenesis of pulmonary hypertension. The molecular mechanisms that underlie hypoxia-associated pulmonary hypertension are not well-defined.Bcr and abr null mutant mice were compared to wild type controls for the development of pulmonary hypertension after exposure to hypoxia. Also, pulmonary arterial smooth muscle cells from those mice were cultured in hypoxia and examined for proliferation, p38 activation and IL-6 production. Mice lacking Bcr or Abr exposed to hypoxia developed increased right ventricular pressure, hypertrophy and pulmonary vascular remodeling. Perivascular leukocyte infiltration in the lungs was increased, and under hypoxia bcr-/- and abr-/- macrophages generated more reactive oxygen species. Consistent with a contribution of inflammation and oxidative stress in pulmonary hypertension-associated vascular damage, Bcr and Abr-deficient animals showed elevated endothelial leakage after hypoxia exposure. Hypoxia-treated pulmonary arterial smooth muscle cells from Bcr- or Abr-deficient mice also proliferated faster than those of wild type mice. Moreover, activated Rac1, phosphorylated p38 and interleukin 6 were increased in these cells in the absence of Bcr or Abr. Inhibition of Rac1 activation with Z62954982, a novel Rac inhibitor, decreased proliferation, p38 phosphorylation and IL-6 levels in pulmonary arterial smooth muscle cells exposed to hypoxia.Bcr and Abr play a critical role in down-regulating hypoxia-induced pulmonary hypertension by deactivating Rac1 and, through this, reducing both oxidative stress generated by leukocytes as well as p38 phosphorylation, IL-6 production and proliferation of pulmonary arterial smooth muscle cells.

  10. Increased anxiety and fear memory in adult mice lacking type 2 deiodinase.

    Science.gov (United States)

    Bárez-López, Soledad; Montero-Pedrazuela, Ana; Bosch-García, Daniel; Venero, César; Guadaño-Ferraz, Ana

    2017-10-01

    A euthyroid state in the brain is crucial for its adequate development and function. Impairments in thyroid hormones (THs; T3 or 3,5,3'-triiodothyronine and T4 or thyroxine) levels and availability in brain can lead to neurological alterations and to psychiatric disorders, particularly mood disorders. The thyroid gland synthetizes mainly T4, which is secreted to circulating blood, however, most actions of THs are mediated by T3, the transcriptionally active form. In the brain, intracellular concentrations of T3 are modulated by the activity of type 2 (D2) and type 3 (D3) deiodinases. In the present work, we evaluated learning and memory capabilities and anxiety-like behavior at adult stages in mice lacking D2 (D2KO) and we analyzed the impact of D2-deficiency on TH content and on the expression of T3-dependent genes in the amygdala and the hippocampus. We found that D2KO mice do not present impairments in spatial learning and memory, but they display emotional alterations with increased anxiety-like behavior as well as enhanced auditory-cued fear memory and spontaneous recovery of fear memory following extinction. D2KO mice also presented reduced T3 content in the hippocampus and decreased expression of the T3-dependent gene Dio3 in the amygdala suggesting a hypothyroid status in this structure. We propose that the emotional dysfunctions found in D2KO mice can arise from the reduced T3 content in their brain, which consequently leads to alterations in gene expression with functional consequences. We found a downregulation in the gene encoding for the calcium-binding protein calretinin (Calb2) in the amygdala of D2KO mice that could affect the GABAergic transmission. The current findings in D2KO mice can provide insight into emotional disorders present in humans with DIO2 polymorphisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Post-exposure vaccination with MP-12 lacking NSs protects mice against lethal Rift Valley fever virus challenge.

    Science.gov (United States)

    Gowen, Brian B; Bailey, Kevin W; Scharton, Dionna; Vest, Zachery; Westover, Jonna B; Skirpstunas, Ramona; Ikegami, Tetsuro

    2013-05-01

    Rift Valley fever virus (RVFV) causes severe disease in humans and livestock. There are currently no approved antivirals or vaccines for the treatment or prevention of RVF disease in humans. A major virulence factor of RVFV is the NSs protein, which inhibits host transcription including the interferon (IFN)-β gene and promotes the degradation of dsRNA-dependent protein kinase, PKR. We analyzed the efficacy of the live-attenuated MP-12 vaccine strain and MP-12 variants that lack the NSs protein as post-exposure vaccinations. Although parental MP-12 failed to elicit a protective effect in mice challenged with wild-type (wt) RVFV by the intranasal route, significant protection was demonstrated by vaccination with MP-12 strains lacking NSs when they were administered at 20-30 min post-exposure. Viremia and virus replication in liver, spleen and brain were also inhibited by post-exposure vaccination with MP-12 lacking NSs. The protective effect was mostly lost when vaccination was delayed 6 or 24 h after intranasal RVFV challenge. When mice were challenged subcutaneously, efficacy of MP-12 lacking NSs was diminished, most likely due to more rapid dissemination of wt RVFV. Our findings suggest that post-exposure vaccination with MP-12 lacking NSs may be developed as a novel post-exposure treatment to prevent RVF. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Synapsin III Acts Downstream of Semaphorin 3A/CDK5 Signaling to Regulate Radial Migration and Orientation of Pyramidal Neurons In Vivo

    Directory of Open Access Journals (Sweden)

    Laura E. Perlini

    2015-04-01

    Full Text Available Synapsin III (SynIII is a phosphoprotein that is highly expressed at early stages of neuronal development. Whereas in vitro evidence suggests a role for SynIII in neuronal differentiation, in vivo evidence is lacking. Here, we demonstrate that in vivo downregulation of SynIII expression affects neuronal migration and orientation. By contrast, SynIII overexpression affects neuronal migration, but not orientation. We identify a cyclin-dependent kinase-5 (CDK5 phosphorylation site on SynIII and use phosphomutant rescue experiments to demonstrate its role in SynIII function. Finally, we show that SynIII phosphorylation at the CDK5 site is induced by activation of the semaphorin-3A (Sema3A pathway, which is implicated in migration and orientation of cortical pyramidal neurons (PNs and is known to activate CDK5. Thus, fine-tuning of SynIII expression and phosphorylation by CDK5 activation through Sema3A activity is essential for proper neuronal migration and orientation.

  13. Mice lacking caspase-2 are protected from behavioral changes, but not pathology, in the YAC128 model of Huntington disease

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    Bissada Nagat

    2011-08-01

    Full Text Available Abstract Background Huntington Disease (HD is a neurodegenerative disorder in which caspase activation and cleavage of substrates, including the huntingtin protein, has been invoked as a pathological mechanism. Specific changes in caspase-2 (casp2 activity have been suggested to contribute to the pathogenesis of HD, however unique casp2 cleavage substrates have remained elusive. We thus utilized mice completely lacking casp2 (casp2-/- to examine the role played by casp2 in the progression of HD. This 'substrate agnostic' approach allows us to query the effect of casp2 on HD progression without pre-defining proteolytic substrates of interest. Results YAC128 HD model mice lacking casp2 show protection from well-validated motor and cognitive features of HD, including performance on rotarod, swimming T-maze, pre-pulse inhibition, spontaneous alternation and locomotor tasks. However, the specific pathological features of the YAC128 mice including striatal volume loss and testicular degeneration are unaltered in mice lacking casp2. The application of high-resolution magnetic resonance imaging (MRI techniques validates specific neuropathology in the YAC128 mice that is not altered by ablation of casp2. Conclusions The rescue of behavioral phenotypes in the absence of pathological improvement suggests that different pathways may be operative in the dysfunction of neural circuitry in HD leading to behavioral changes compared to the processes leading to cell death and volume loss. Inhibition of caspase-2 activity may be associated with symptomatic improvement in HD.

  14. Entrainment and phase-shifting by centrifugation abolished in mice lacking functional vestibular input

    Science.gov (United States)

    Fuller, Charles; Ringgold, Kristyn

    The circadian pacemaker can be phase shifted and entrained by appropriately timed locomotor activity, however the mechanism(s) involved remain poorly understood. Recent work in our lab has suggested the involvement of the vestibular otolith organs in activity-induced changes within the circadian timing system (CTS). For example, we have shown that changes in circa-dian period and phase in response to locomotion (wheel running) require functional macular gravity receptors. We believe the neurovestibular system is responsible for the transduction of gravitoinertial input associated with the types of locomotor activity that are known to af-fect the pacemaker. This study investigated the hypothesis that daily, timed gravitoinertial stimuli, as applied by centrifugation. would induce entrainment of circadian rhythms in only those animals with functional afferent vestibular input. To test this hypothesis, , chemically labyrinthectomized (Labx) mice, mice lacking macular vestibular input (head tilt or hets) and wildtype (WT) littermates were implanted i.p. with biotelemetry and individually housed in a 4-meter diameter centrifuge in constant darkness (DD). After 2 weeks in DD, the mice were exposed daily to 2G via centrifugation from 1000-1200 for 9 weeks. Only WT mice showed entrainment to the daily 2G pulse. The 2G pulse was then re-set to occur at 1200-1400 for 4 weeks. Only WT mice demonstrated a phase shift in response to the re-setting of the 2G pulse and subsequent re-entrainment to the new centrifugation schedule. These results provide further evidence that gravitoinertial stimuli require a functional vestibular system to both en-train and phase shift the CTS. Entrainment among only WT mice supports the role of macular gravity receptive cells in modulation of the CTS while also providing a functional mechanism by which gravitoinertial stimuli, including locomotor activity, may affect the pacemaker.

  15. Remodeling of the Cervix and Parturition in Mice Lacking the Progesterone Receptor B Isoform1

    Science.gov (United States)

    Yellon, Steven M.; Oshiro, Bryan T.; Chhaya, Tejas Y.; Lechuga, Thomas J.; Dias, Rejane M.; Burns, Alexandra E.; Force, Lindsey; Apostolakis, Ede M.

    2011-01-01

    Withdrawal of progestational support for pregnancy is part of the final common pathways for parturition, but the role of nuclear progesterone receptor (PGR) isoforms in this process is not known. To determine if the PGR-B isoform participates in cervical remodeling at term, cervices were obtained from mice lacking PGR-B (PGR-BKO) and from wild-type (WT) controls before or after birth. PGR-BKO mice gave birth to viable pups at the same time as WT controls during the early morning of Day 19 postbreeding. Morphological analyses indicated that by the day before birth, cervices from PGR-BKO and WT mice had increased in size, with fewer cell nuclei/area as well as diminished collagen content and structure, as evidenced by optical density of picrosirius red-stained sections, compared to cervices from nonpregnant mice. Moreover, increased numbers of resident macrophages, but not neutrophils, were found in the prepartum cervix of PGR-BKO compared to nonpregnant mice, parallel to findings in WT mice. These results suggest that PGR-B does not contribute to the growth or degradation of the extracellular matrix or proinflammatory processes associated with recruitment of macrophages in the cervix leading up to birth. Rather, other receptors may contribute to the progesterone-dependent mechanism that promotes remodeling of the cervix during pregnancy and in the proinflammatory process associated with ripening before parturition. PMID:21613631

  16. Fetal growth retardation and lack of hypotaurine in ezrin knockout mice.

    Directory of Open Access Journals (Sweden)

    Tomohiro Nishimura

    Full Text Available Ezrin is a membrane-associated cytoplasmic protein that serves to link cell-membrane proteins with the actin-based cytoskeleton, and also plays a role in regulation of the functional activities of some transmembrane proteins. It is expressed in placental trophoblasts. We hypothesized that placental ezrin is involved in the supply of nutrients from mother to fetus, thereby influencing fetal growth. The aim of this study was firstly to clarify the effect of ezrin on fetal growth and secondly to determine whether knockout of ezrin is associated with decreased concentrations of serum and placental nutrients. Ezrin knockout mice (Ez(-/- were confirmed to exhibit fetal growth retardation. Metabolome analysis of fetal serum and placental extract of ezrin knockout mice by means of capillary electrophoresis-time-of-flight mass spectrometry revealed a markedly decreased concentration of hypotaurine, a precursor of taurine. However, placental levels of cysteine and cysteine sulfinic acid (precursors of hypotaurine and taurine were not affected. Lack of hypotaurine in Ez(-/- mice was confirmed by liquid chromatography with tandem mass spectrometry. Administration of hypotaurine to heterogenous dams significantly decreased the placenta-to-maternal plasma ratio of hypotaurine in wild-type fetuses but only slightly decreased it in ezrin knockout fetuses, indicating that the uptake of hypotaurine from mother to placenta is saturable and that disruption of ezrin impairs the uptake of hypotaurine by placental trophoblasts. These results indicate that ezrin is required for uptake of hypotaurine from maternal serum by placental trophoblasts, and plays an important role in fetal growth.

  17. Lack of mitochondrial trifunctional protein in mice causes neonatal hypoglycemia and sudden death

    OpenAIRE

    Ibdah, Jamal A.; Paul, Hyacinth; Zhao, Yiwen; Binford, Scott; Salleng, Ken; Cline, Mark; Matern, Dietrich; Bennett, Michael J.; Rinaldo, Piero; Strauss, Arnold W.

    2001-01-01

    Mitochondrial trifunctional protein (MTP) is a hetero-octamer of four α and four β subunits that catalyzes the final three steps of mitochondrial long chain fatty acid β-oxidation. Human MTP deficiency causes Reye-like syndrome, cardiomyopathy, or sudden unexpected death. We used gene targeting to generate an MTP α subunit null allele and to produce mice that lack MTP α and β subunits. The Mtpa–/– fetuses accumulate long chain fatty acid metabolites and have low birth weight compared with the...

  18. Attenuated traumatic axonal injury and improved functional outcome after traumatic brain injury in mice lacking Sarm1.

    Science.gov (United States)

    Henninger, Nils; Bouley, James; Sikoglu, Elif M; An, Jiyan; Moore, Constance M; King, Jean A; Bowser, Robert; Freeman, Marc R; Brown, Robert H

    2016-04-01

    Axonal degeneration is a critical, early event in many acute and chronic neurological disorders. It has been consistently observed after traumatic brain injury, but whether axon degeneration is a driver of traumatic brain injury remains unclear. Molecular pathways underlying the pathology of traumatic brain injury have not been defined, and there is no efficacious treatment for traumatic brain injury. Here we show that mice lacking the mouse Toll receptor adaptor Sarm1 (sterile α/Armadillo/Toll-Interleukin receptor homology domain protein) gene, a key mediator of Wallerian degeneration, demonstrate multiple improved traumatic brain injury-associated phenotypes after injury in a closed-head mild traumatic brain injury model. Sarm1(-/-) mice developed fewer β-amyloid precursor protein aggregates in axons of the corpus callosum after traumatic brain injury as compared to Sarm1(+/+) mice. Furthermore, mice lacking Sarm1 had reduced plasma concentrations of the phophorylated axonal neurofilament subunit H, indicating that axonal integrity is maintained after traumatic brain injury. Strikingly, whereas wild-type mice exibited a number of behavioural deficits after traumatic brain injury, we observed a strong, early preservation of neurological function in Sarm1(-/-) animals. Finally, using in vivo proton magnetic resonance spectroscopy we found tissue signatures consistent with substantially preserved neuronal energy metabolism in Sarm1(-/-) mice compared to controls immediately following traumatic brain injury. Our results indicate that the SARM1-mediated prodegenerative pathway promotes pathogenesis in traumatic brain injury and suggest that anti-SARM1 therapeutics are a viable approach for preserving neurological function after traumatic brain injury. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. A high-fat diet induces bone loss in mice lacking the Alox5 gene.

    Science.gov (United States)

    Le, Phuong; Kawai, Masanobu; Bornstein, Sheila; DeMambro, Victoria E; Horowitz, Mark C; Rosen, Clifford J

    2012-01-01

    5-Lipoxygenase catalyzes leukotriene generation from arachidonic acid. The gene that encodes 5-lipoxygenase, Alox5, has been identified in genome-wide association and mouse Quantitative Trait Locus studies as a candidate gene for obesity and low bone mass. Thus, we tested the hypothesis that Alox5(-/-) mice would exhibit metabolic and skeletal changes when challenged by a high-fat diet (HFD). On a regular diet, Alox5(-/-) mice did not differ in total body weight, percent fat mass, or bone mineral density compared with wild-type (WT) controls (P < 0.05). However, when placed on a HFD, Alox5(-/-) gained more fat mass and lost greater areal bone mass vs. WT (P < 0.05). Microarchitectural analyses revealed that on a HFD, WT showed increases in cortical area (P < 0.01) and trabecular thickness (P < 0.01), whereas Alox5(-/-) showed no change in cortical parameters but a decrease in trabecular number (P < 0.05) and bone volume fraction compared with WT controls (P < 0.05). By histomorphometry, a HFD did not change bone formation rates of either strain but produced an increase in osteoclast number per bone perimeter in Alox5(-/-) mice (P < 0.03). In vitro, osteoclastogenesis of marrow stromal cells was enhanced in mutant but not WT mice fed a HFD. Gene expression for Rankl, Pparg, and Cox-2 was greater in the femur of Alox5(-/-) than WT mice on a HFD (P < 0.01), but these increases were suppressed in the Alox5(-/-) mice after 8 wk of treatment with celecoxib, a cyclooxygenase-2 inhibitor. In sum, there is a strong gene by environmental interaction for bone mass when mice lacking the Alox5 gene are fed a HFD.

  20. Minor cell-death defects but reduced tumor latency in mice lacking the BH3-only proteins Bad and Bmf.

    Science.gov (United States)

    Baumgartner, F; Woess, C; Pedit, V; Tzankov, A; Labi, V; Villunger, A

    2013-01-31

    Proapoptotic Bcl-2 family members of the Bcl-2 homology (BH)3-only subgroup are critical for the establishment and maintenance of tissue homeostasis and can mediate apoptotic cell death in response to developmental cues or exogenously induced forms of cell stress. On the basis of the biochemical experiments as well as genetic studies in mice, the BH3-only proteins Bad and Bmf have been implicated in different proapoptotic events such as those triggered by glucose- or trophic factor-deprivation, glucocorticoids, or histone deacetylase inhibition, as well as suppression of B-cell lymphomagenesis upon aberrant expression of c-Myc. To address possible redundancies in cell death regulation and tumor suppression, we generated compound mutant mice lacking both genes. Our studies revealed lack of redundancy in most paradigms of lymphocyte apoptosis tested in tissue culture. Only spontaneous cell death of thymocytes kept in low glucose or that of pre-B cells deprived of cytokines was significantly delayed when both genes were lacking. Of note, despite these minor apoptosis defects we observed compromised lymphocyte homeostasis in vivo that affected mainly the B-cell lineage. Long-term follow-up revealed significantly reduced latency to spontaneous tumor formation in aged mice when both genes were lacking. Together our study suggests that Bad and Bmf co-regulate lymphocyte homeostasis and limit spontaneous transformation by mechanisms that may not exclusively be linked to the induction of lymphocyte apoptosis.

  1. Increased brain damage after ischaemic stroke in mice lacking the chemokine receptor CCR5

    Science.gov (United States)

    Sorce, S; Bonnefont, J; Julien, S; Marq-Lin, N; Rodriguez, I; Dubois-Dauphin, M; Krause, KH

    2010-01-01

    Background and purpose: The chemokine receptor CCR5 is well known for its function in immune cells; however, it is also expressed in the brain, where its specific role remains to be elucidated. Because genetic factors may influence the risk of developing cerebral ischaemia or affect its clinical outcome, we have analysed the role of CCR5 in experimental stroke. Experimental approach: Permanent cerebral ischaemia was performed by occlusion of the middle cerebral artery in wild-type and CCR5-deficient mice. Locomotor behaviour, infarct size and histochemical alterations were analysed at different time points after occlusion. Key results: The cerebral vasculature was comparable in wild-type and CCR5-deficient mice. However, the size of the infarct and the motor deficits after occlusion were markedly increased in CCR5-deficient mice as compared with wild type. No differences between wild-type and CCR5-deficient mice were elicited by occlusion with respect to the morphology and abundance of astrocytes and microglia. Seven days after occlusion the majority of CCR5-deficient mice displayed neutrophil invasion in the infarct region, which was not observed in wild type. As compared with wild type, the infarct regions of CCR5-deficient mice were characterized by increased neuronal death. Conclusions and implications: Lack of CCR5 increased the severity of brain injury following occlusion of the middle cerebral artery. This is of particular interest with respect to the relatively frequent occurrence of CCR5 deficiency in the human population (1–2% of the Caucasian population) and the advent of CCR5 inhibitors as novel drugs. PMID:20423342

  2. Mice lacking cyclin-dependent kinase-like 5 manifest autistic and ADHD-like behaviors.

    Science.gov (United States)

    Jhang, Cian-Ling; Huang, Tzyy-Nan; Hsueh, Yi-Ping; Liao, Wenlin

    2017-10-15

    Neurodevelopmental disorders frequently share common clinical features and appear high rate of comorbidity, such as those present in patients with attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). While characterizing behavioral phenotypes in the mouse model of cyclin-dependent kinase-like 5 (CDKL5) disorder, a neurodevelopmental disorder caused by mutations in the X-linked gene encoding CDKL5, we found that these mice manifested behavioral phenotypes mimicking multiple key features of ASD, such as impaired social interaction and communication, as well as increased stereotypic digging behaviors. These mice also displayed hyper-locomotion, increased aggressiveness and impulsivity, plus deficits in motor and associative learning, resembling primary symptoms of ADHD. Through brain region-specific biochemical analysis, we uncovered that loss of CDKL5 disrupts dopamine synthesis and the expression of social communication-related key genes, such as forkhead-box P2 and mu-opioid receptor, in the corticostriatal circuit. Together, our findings support that CDKL5 plays a role in the comorbid features of autism and ADHD, and mice lacking CDKL5 may serve as an animal model to study the molecular and circuit mechanisms underlying autism-ADHD comorbidity. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Spdef null mice lack conjunctival goblet cells and provide a model of dry eye.

    Science.gov (United States)

    Marko, Christina K; Menon, Balaraj B; Chen, Gang; Whitsett, Jeffrey A; Clevers, Hans; Gipson, Ilene K

    2013-07-01

    Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef(-/-) mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef(-/-) mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef(-/-) mice revealed down-regulation of goblet cell-specific genes (Muc5ac, Tff1, Gcnt3). Up-regulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and proinflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are up-regulated in dry eye. Interestingly, four Wnt pathway genes were down-regulated. SPDEF expression was significantly decreased in the conjunctival epithelium of Sjögren syndrome patients with dry eye and decreased goblet cell mucin expression. These data demonstrate that Spdef is required for conjunctival goblet cell differentiation and down-regulation of SPDEF may play a role in human dry eye with goblet cell loss. Spdef(-/-) mice have an ocular surface phenotype similar to that in moderate dry eye, providing a new, more convenient model for the disease. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  4. Mice lacking melanin-concentrating hormone receptor 1 demonstrate increased heart rate associated with altered autonomic activity.

    Science.gov (United States)

    Astrand, Annika; Bohlooly-Y, Mohammad; Larsdotter, Sara; Mahlapuu, Margit; Andersén, Harriet; Tornell, Jan; Ohlsson, Claes; Snaith, Mike; Morgan, David G A

    2004-10-01

    Melanin-concentrating hormone (MCH) plays an important role in energy balance. The current studies were carried out on a new line of mice lacking the rodent MCH receptor (MCHR1(-/-) mice). These mice confirmed the previously reported lean phenotype characterized by increased energy expenditure and modestly increased caloric intake. Because MCH is expressed in the lateral hypothalamic area, which also has an important role in the regulation of the autonomic nervous system, heart rate and blood pressure were measured by a telemetric method to investigate whether the increased energy expenditure in these mice might be due to altered autonomic nervous system activity. Male MCHR1(-/-) mice demonstrated a significantly increased heart rate [24-h period: wild type 495 +/- 4 vs. MCHR1(-/-) 561 +/- 8 beats/min (P dark phase: wild type 506 +/- 8 vs. MCHR1(-/-) 582 +/- 9 beats/min (P light phase: wild type 484 +/- 13 vs. MCHR1(-/-) 539 +/- 9 beats/min (P vs. MCHR1(-/-) 113 +/- 0.4 mmHg (P > 0.05)]. Locomotor activity and core body temperature were higher in the MCHR1(-/-) mice during the dark phase only and thus temporally dissociated from heart rate differences. On fasting, wild-type animals rapidly downregulated body temperature and heart rate. MCHR1(-/-) mice displayed a distinct delay in the onset of this downregulation. To investigate the mechanism underlying these differences, autonomic blockade experiments were carried out. Administration of the adrenergic antagonist metoprolol completely reversed the tachycardia seen in MCHR1(-/-) mice, suggesting an increased sympathetic tone.

  5. Lethal Cardiomyopathy in Mice Lacking Transferrin Receptor in the Heart

    Directory of Open Access Journals (Sweden)

    Wenjing Xu

    2015-10-01

    Full Text Available Both iron overload and iron deficiency have been associated with cardiomyopathy and heart failure, but cardiac iron utilization is incompletely understood. We hypothesized that the transferrin receptor (Tfr1 might play a role in cardiac iron uptake and used gene targeting to examine the role of Tfr1 in vivo. Surprisingly, we found that decreased iron, due to inactivation of Tfr1, was associated with severe cardiac consequences. Mice lacking Tfr1 in the heart died in the second week of life and had cardiomegaly, poor cardiac function, failure of mitochondrial respiration, and ineffective mitophagy. The phenotype could only be rescued by aggressive iron therapy, but it was ameliorated by administration of nicotinamide riboside, an NAD precursor. Our findings underscore the importance of both Tfr1 and iron in the heart, and may inform therapy for patients with heart failure.

  6. The impact of synapsin III gene on the neurometabolite level alterations after single-dose methylphenidate in attention-deficit hyperactivity disorder patients

    Directory of Open Access Journals (Sweden)

    Başay Ö

    2016-05-01

    Full Text Available Ömer Başay,1 Burge Kabukcu Basay,1 Huseyin Alacam,2 Onder Ozturk,1 Ahmet Buber,1 Senay Gorucu Yilmaz,3 Yılmaz Kıroğlu,4 Mehmet Emin Erdal,5 Hasan Herken2 1Department of Child and Adolescent Psychiatry, Faculty of Medicine, Pamukkale University, Denizli, 2Department of Psychiatry, Faculty of Medicine, Pamukkale University, Denizli, 3Department of Nutrition and Dietetics, Faculty of Health Sciences, Gaziantep University, Gaziantep, 4Department of Radiology, School of Medicine, Pamukkale University, Denizli, 5Department of Medical Biology and Genetics, Faculty of Medicine, Mersin University, Mersin, Turkey Objective: To investigate the neurometabolite level changes according to synapsin III gene rs133945G>A and rs133946C>G polymorphisms by using magnetic resonance spectroscopy (MRS in patients with attention-deficit hyperactivity disorder (ADHD.Methods: Fifty-seven adults diagnosed with ADHD were recruited for the study. The participants were examined by single-voxel 1H MRS when medication naïve and 30 minutes after oral administration of 10 mg methylphenidate (Mph. Those who had been on a stimulant discontinued the medication 48 hours before MRS imaging. Spectra were taken from the anterior cingulate cortex, dorsolateral prefrontal cortex, striatum, and cerebellum, and N-acetylaspartate (NAA, choline, and creatine levels were examined. For genotyping of the synapsin III gene polymorphisms, DNA was isolated from peripheral blood leukocytes. The effects of age, sex, and ADHD subtypes were controlled in the analyses.Results: After a single dose of Mph, choline levels increased significantly in the striatum of rs133945G>A polymorphism-GG genotypes (P=0.020 and NAA levels rose in the anterior cingulate cortex of rs133946C>G polymorphism-CG genotypes (P=0.014. Both rs133945G>A and rs133946C>G polymorphisms were found to statistically significantly affect the alteration of NAA levels in response to Mph in dorsolateral prefrontal cortex with

  7. Time-place learning and memory persist in mice lacking functional Per1 and Per2 clock genes.

    Science.gov (United States)

    Mulder, C; Van Der Zee, E A; Hut, R A; Gerkema, M P

    2013-12-01

    With time-place learning, animals link a stimulus with the location and the time of day. This ability may optimize resource localization and predator avoidance in daily changing environments. Time-place learning is a suitable task to study the interaction of the circadian system and memory. Previously, we showed that time-place learning in mice depends on the circadian system and Cry1 and/or Cry2 clock genes. We questioned whether time-place learning is Cry specific or also depends on other core molecular clock genes. Here, we show that Per1/Per2 double mutant mice, despite their arrhythmic phenotype, acquire time-place learning similar to wild-type mice. As well as an established role in circadian rhythms, Per genes have also been implicated in the formation and storage of memory. We found no deficiencies in short-term spatial working memory in Per mutant mice compared to wild-type mice. Moreover, both Per mutant and wild-type mice showed similar long-term memory for contextual features of a paradigm (a mild foot shock), measured in trained mice after a 2-month nontesting interval. In contrast, time-place associations were lost in both wild-type and mutant mice after these 2 months, suggesting a lack of maintained long-term memory storage for this type of information. Taken together, Cry-dependent time-place learning does not require Per genes, and Per mutant mice showed no PER-specific short-term or long-term memory deficiencies. These results limit the functional role of Per clock genes in the circadian regulation of time-place learning and memory.

  8. Protein kinase A mediates adenosine A2a receptor modulation of neurotransmitter release via synapsin I phosphorylation in cultured cells from medulla oblongata.

    Science.gov (United States)

    Matsumoto, Joao Paulo Pontes; Almeida, Marina Gomes; Castilho-Martins, Emerson Augusto; Costa, Maisa Aparecida; Fior-Chadi, Debora Rejane

    2014-08-01

    Synaptic transmission is an essential process for neuron physiology. Such process is enabled in part due to modulation of neurotransmitter release. Adenosine is a synaptic modulator of neurotransmitter release in the Central Nervous System, including neurons of medulla oblongata, where several nuclei are involved with neurovegetative reflexes. Adenosine modulates different neurotransmitter systems in medulla oblongata, specially glutamate and noradrenaline in the nucleus tractussolitarii, which are involved in hypotensive responses. However, the intracellular mechanisms involved in this modulation remain unknown. The adenosine A2a receptor modulates neurotransmitter release by activating two cAMP protein effectors, the protein kinase A and the exchange protein activated by cAMP. Therefore, an in vitro approach (cultured cells) was carried out to evaluate modulation of neurotransmission by adenosine A2a receptor and the signaling intracellular pathway involved. Results show that the adenosine A2a receptor agonist, CGS 21680, increases neurotransmitter release, in particular, glutamate and noradrenaline and such response is mediated by protein kinase A activation, which in turn increased synapsin I phosphorylation. This suggests a mechanism of A2aR modulation of neurotransmitter release in cultured cells from medulla oblongata of Wistar rats and suggest that protein kinase A mediates this modulation of neurotransmitter release via synapsin I phosphorylation. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  9. Mice lacking major brain gangliosides develop parkinsonism.

    Science.gov (United States)

    Wu, Gusheng; Lu, Zi-Hua; Kulkarni, Neil; Amin, Ruchi; Ledeen, Robert W

    2011-09-01

    Parkinson's disease (PD) is the second most prevalent late-onset neurodegenerative disorder that affects nearly 1% of the global population aged 65 and older. Whereas palliative treatments are in use, the goal of blocking progression of motor and cognitive disability remains unfulfilled. A better understanding of the basic pathophysiological mechanisms underlying PD would help to advance that goal. The present study provides evidence that brain ganglioside abnormality, in particular GM1, may be involved. This is based on use of the genetically altered mice with disrupted gene Galgt1 for GM2/GD2 synthase which depletes GM2/GD2 and all the gangliotetraose gangliosides that constitute the major molecular species of brain. These knockout mice show overt motor disability on aging and clear indications of motor impairment with appropriate testing at an earlier age. This disability was rectified by L-dopa administration. These mice show other characteristic symptoms of PD, including depletion of striatal dopamine (DA), loss of DA neurons of the substantia nigra pars compacta, and aggregation of alpha synuclein. These manifestations of parkinsonism were largely attenuated by administration of LIGA-20, a membrane permeable analog of GM1 that penetrates the blood brain barrier and enters living neurons. These results suggest that perturbation of intracellular mechanisms mediated by intracellular GM1 may be a contributing factor to PD.

  10. Prolongation of chemically-induced methemoglobinemia in mice lacking α-synuclein: A novel pharmacologic and toxicologic phenotype

    Directory of Open Access Journals (Sweden)

    Yien-Ming Kuo

    2015-01-01

    Full Text Available The protein α-synuclein is considered central to the pathogenesis of Parkinson disease (PD on genetic and histopathological grounds. It is widely expressed in fetal life and continues to be highly expressed in adult neural tissues, red blood cells and platelets, while the remainder of adult tissues are reported to have little or no expression. Despite cellular and molecular evidence for a role in neuronal function including synaptic vesicle trafficking, neurotransmitter release, mitochondrial function, lipid metabolism, neurogenesis, neuroprotection, and neuromelanin biosynthesis, mice ablated for the gene encoding α-synuclein (Snca have little or no neurological phenotype. Thus, nearly 20 years of intensive study have yet to reveal conclusively what the normal function of this highly abundant protein is in the nervous system. Interestingly, α-synuclein has also been shown to have enzymatic activity as a ferrireductase capable of reducing Fe+3 to Fe+2. Given its abundant expression in red blood cells, we set out to explore the role of α-synuclein in converting chemically-induced Fe+3 methemoglobin to normal Fe+2 hemoglobin. Initial in vivo experiments with the potent methemoglobin inducer, para-aminopropiophenone and its active metabolite, 4-hydroxy para-aminopropiophenone, demonstrated significantly greater and more prolonged methemoglobinemia in Snca−/− mice compared to Snca+/+ mice. In vitro experiments with red blood cells, however, and in vivo experiments in genetically engineered mouse strains that differ in their α-synuclein expression in various tissues, including the nervous system, red blood cells and liver, revealed that contrary to the initial hypothesis, a lack of expression of α-synuclein in red blood cells did not correlate with higher levels or more prolonged duration of methemoglobinemia. Instead, the greater sensitivity to chemically induced methemoglobinemia correlated with the absence of hepatic

  11. Sociability Deficits and Altered Amygdala Circuits in Mice Lacking Pcdh10, an Autism Associated Gene.

    Science.gov (United States)

    Schoch, Hannah; Kreibich, Arati S; Ferri, Sarah L; White, Rachel S; Bohorquez, Dominique; Banerjee, Anamika; Port, Russell G; Dow, Holly C; Cordero, Lucero; Pallathra, Ashley A; Kim, Hyong; Li, Hongzhe; Bilker, Warren B; Hirano, Shinji; Schultz, Robert T; Borgmann-Winter, Karin; Hahn, Chang-Gyu; Feldmeyer, Dirk; Carlson, Gregory C; Abel, Ted; Brodkin, Edward S

    2017-02-01

    Behavioral symptoms in individuals with autism spectrum disorder (ASD) have been attributed to abnormal neuronal connectivity, but the molecular bases of these behavioral and brain phenotypes are largely unknown. Human genetic studies have implicated PCDH10, a member of the δ2 subfamily of nonclustered protocadherin genes, in ASD. PCDH10 expression is enriched in the basolateral amygdala, a brain region implicated in the social deficits of ASD. Previous reports indicate that Pcdh10 plays a role in axon outgrowth and glutamatergic synapse elimination, but its roles in social behaviors and amygdala neuronal connectivity are unknown. We hypothesized that haploinsufficiency of Pcdh10 would reduce social approach behavior and alter the structure and function of amygdala circuits. Mice lacking one copy of Pcdh10 (Pcdh10 +/- ) and wild-type littermates were assessed for social approach and other behaviors. The lateral/basolateral amygdala was assessed for dendritic spine number and morphology, and amygdala circuit function was studied using voltage-sensitive dye imaging. Expression of Pcdh10 and N-methyl-D-aspartate receptor (NMDAR) subunits was assessed in postsynaptic density fractions of the amygdala. Male Pcdh10 +/- mice have reduced social approach behavior, as well as impaired gamma synchronization, abnormal spine morphology, and reduced levels of NMDAR subunits in the amygdala. Social approach deficits in Pcdh10 +/- male mice were rescued with acute treatment with the NMDAR partial agonist d-cycloserine. Our studies reveal that male Pcdh10 +/- mice have synaptic and behavioral deficits, and establish Pcdh10 +/- mice as a novel genetic model for investigating neural circuitry and behavioral changes relevant to ASD. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. Mice lacking neuropeptide Y show increased sensitivity to cocaine

    DEFF Research Database (Denmark)

    Sørensen, Gunnar; Woldbye, David Paul Drucker

    2012-01-01

    There is increasing data implicating neuropeptide Y (NPY) in the neurobiology of addiction. This study explored the possible role of NPY in cocaine-induced behavior using NPY knockout mice. The transgenic mice showed a hypersensitive response to cocaine in three animal models of cocaine addiction...

  13. Exposure of Neonatal Mice to Tobacco Smoke Disturbs Synaptic Proteins and Spatial Learning and Memory from Late Infancy to Early Adulthood.

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    Larissa Helena Torres

    Full Text Available Exposure to environmental tobacco smoke (ETS in the early postnatal period has been associated with several diseases; however, little is known about the brain effects of ETS exposure during this critical developmental period or the long-term consequences of this exposure. This study investigated the effects of the early postnatal ETS exposure on both reference and working memory, synaptic proteins and BDNF from late infancy to early adulthood (P3-P73. BALB/c mice were exposed to ETS generated from 3R4F reference research cigarettes (0.73 mg of nicotine/cigarette from P3 to P14. Spatial reference and working memory were evaluated in the Morris water maze during infancy (P20-P29, adolescence (P37-P42 and adulthood (P67-P72. Synapsin, synaptophysin, PSD95 and brain-derived neurotrophic factor (BDNF were assessed at P15, P35 and P65 by immunohistochemistry and immunoblotting. Mice that were exposed to ETS during the early postnatal period showed poorer performance in the spatial reference memory task. Specifically, the ETS-exposed mice exhibited a significantly reduced time and distance traveled in the target quadrant and in the platform location area than the controls at all ages evaluated. In the spatial working memory task, ETS disrupted the maintenance but not the acquisition of the critical spatial information in both infancy and adolescence. ETS also induced changes in synaptic components, including decreases in synapsin, synaptophysin, PSD95 and BDNF levels in the hippocampus. Exposure to ETS in the early postnatal period disrupts both spatial reference and working memory; these results may be related to changes in synaptogenesis in the hippocampus. Importantly, most of these effects were not reversed even after a long exposure-free period.

  14. [Development of the Human Olfactory Bulbs in the Prenatal Ontogenesis: an Immunochistochemical Study with Markers of Presynaptic Terminals (anti-SNAP-25, -Synapsin-I, -Synaptophysin)].

    Science.gov (United States)

    Kharlamova, A S; Barabanov, V M; Saveliev, S V

    2015-01-01

    We provide the data of the olfactory bulbs (OB) development in the human fetuses on the stages from 8 week to birth. Immunochistochemical markers of presynaptic terminals (anti-SNAP-25, -synapsin-I, -synaptophysin) were used to evaluate the maturation of the OB. Differentiation of the OB layers begins from periphery, which implicitly evidences that growth of the olfactory nerves fibers induses not only anatomical differentiation of the OB, but also differentiation of its functional layers. The sites of the developing glomerulus are revealed using the immunochistochemical prosedure on the stage before distinct glomerulus can be identified with common histological procedure. OB conductive system demonstrates immunoreactivity with the antibodies to the presynaptic proteins on the all stages from 10-11 weeks of fetus development. Four stages of the OB development are described. All functional layers of the OB are mature at the 22-weeks stage. Further differentiation of the OB neuroblasts, including lamina formation of the internal granular leyer, glomerular layer development, OB growth continue after 20-22 weeks stage until 38-40 weeks of the fetus develoment. Patterns of the immunoreactivity with antibodies to SNAP-25, synapsin-I and synaptophysin are completely appropriate to those of adult's OB on the 38-40 weeks of the prenatal development. Complete maturity of the human OB is achived at 38-40 weeks of the prenatal development.

  15. Mice lacking the synaptic adhesion molecule Neph2/Kirrel3 display moderate hyperactivity and defective novel object preference

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    Su Yeon eChoi

    2015-07-01

    Full Text Available Synaptic adhesion molecules regulate diverse aspects of neuronal synapse development, including synapse specificity, formation, and maturation. Neph2, also known as Kirrel3, is an immunoglobulin superfamily adhesion molecule implicated in intellectual disability, neurocognitive delay associated with Jacobsen syndrome, and autism spectrum disorders. We here report mice lacking Neph2 (Neph2–/– mice display moderate hyperactivity in a familiar but not novel environment and novel object recognition deficit with normal performances in Morris water maze spatial learning and memory, contextual fear conditioning and extinction, and pattern separation tests. These mice show normal levels of anxiety-like behaviors, social interaction, and repetitive behaviors. At the synapse level, Neph2–/– dentate gyrus granule cells exhibit unaltered dendritic spine density and spontaneous excitatory synaptic transmission. These results suggest that Neph2 is important for normal locomotor activity and object recognition memory.

  16. Analgesic tone conferred by constitutively active mu opioid receptors in mice lacking β-arrestin 2

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    Hales Tim G

    2011-04-01

    Full Text Available Abstract Hedonic reward, dependence and addiction are unwanted effects of opioid analgesics, linked to the phasic cycle of μ opioid receptor activation, tolerance and withdrawal. In vitro studies of recombinant G protein coupled receptors (GPCRs over expressed in cell lines reveal an alternative tonic signaling mechanism that is independent of agonist. Such studies demonstrate that constitutive GPCR signaling can be inhibited by inverse agonists but not by neutral antagonists. However, ligand-independent activity has been difficult to examine in vivo, at the systems level, due to relatively low levels of constitutive activity of most GPCRs including μ receptors, often necessitating mutagenesis or pharmacological manipulation to enhance basal signaling. We previously demonstrated that the absence of β-arrestin 2 (β-arr2 augments the constitutive coupling of μ receptors to voltage-activated Ca2+ channels in primary afferent dorsal root ganglion neurons from β-arr2-/- mice. We used this in vitro approach to characterize neutral competitive antagonists and inverse agonists of the constitutively active wild type μ receptors in neurons. We administered these agents to β-arr2-/- mice to explore the role of constitutive μ receptor activity in nociception and hedonic tone. This study demonstrates that the induction of constitutive μ receptor activity in vivo in β-arr2-/- mice prolongs tail withdrawal from noxious heat, a phenomenon that was reversed by inverse agonists, but not by antagonists that lack negative efficacy. By contrast, the aversive effects of inverse agonists were similar in β-arr2-/- and β-arr2+/+ mice, suggesting that hedonic tone was unaffected.

  17. Lack of tau proteins rescues neuronal cell death and decreases amyloidogenic processing of APP in APP/PS1 mice.

    Science.gov (United States)

    Leroy, Karelle; Ando, Kunie; Laporte, Vincent; Dedecker, Robert; Suain, Valérie; Authelet, Michèle; Héraud, Céline; Pierrot, Nathalie; Yilmaz, Zehra; Octave, Jean-Noël; Brion, Jean-Pierre

    2012-12-01

    Lack of tau expression has been reported to protect against excitotoxicity and to prevent memory deficits in mice expressing mutant amyloid precursor protein (APP) identified in familial Alzheimer disease. In APP mice, mutant presenilin 1 (PS1) enhances generation of Aβ42 and inhibits cell survival pathways. It is unknown whether the deficient phenotype induced by concomitant expression of mutant PS1 is rescued by absence of tau. In this study, we have analyzed the effect of tau deletion in mice expressing mutant APP and PS1. Although APP/PS1/tau(+/+) mice had a reduced survival, developed spatial memory deficits at 6 months and motor impairments at 12 months, these deficits were rescued in APP/PS1/tau(-/-) mice. Neuronal loss and synaptic loss in APP/PS1/tau(+/+) mice were rescued in the APP/PS1/tau(-/-) mice. The amyloid plaque burden was decreased by roughly 50% in the cortex and the spinal cord of the APP/PS1/tau(-/-) mice. The levels of soluble and insoluble Aβ40 and Aβ42, and the Aβ42/Aβ40 ratio were reduced in APP/PS1/tau(-/-) mice. Levels of phosphorylated APP, of β-C-terminal fragments (CTFs), and of β-secretase 1 (BACE1) were also reduced, suggesting that β-secretase cleavage of APP was reduced in APP/PS1/tau(-/-) mice. Our results indicate that tau deletion had a protective effect against amyloid induced toxicity even in the presence of mutant PS1 and reduced the production of Aβ. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  18. Ketamine Does Not Produce Relief of Neuropathic Pain in Mice Lacking the β-Common Receptor (CD131)

    Science.gov (United States)

    Swartjes, Maarten; Niesters, Marieke; Heij, Lara; Dunne, Ann; Aarts, Leon; Hand, Carla Cerami; Kim, Hyung-Suk; Brines, Michael; Cerami, Anthony; Dahan, Albert

    2013-01-01

    Neuropathic pain (NP) is a debilitating condition associated with traumatic, metabolic, autoimmune and neurological etiologies. Although the triggers for NP are diverse, there are common underlying pathways, including activation of immune cells in the spinal cord and up-regulation of the N-methyl-D-aspartate receptor (NMDAR). Ketamine, a well-known NDMAR antagonist, reduces neuropathic pain in a sustained manner. Recent study has shown that the novel 11-amino acid peptide erythropoietin derivative ARA290 produces a similar, long-lasting relief of NP. Here, we show that both drugs also have similar effects on the expression of mRNA of the NMDAR, as well as that of microglia, astrocytes and chemokine (C-C motif) ligand 2, all-important contributors to the development of NP. Although the effects of ketamine and ARA 290 on NP and its molecular mediators suggest a common mechanism of action, ARA 290 has no affinity for the NMDAR and acts specifically via the innate repair receptor (IRR) involved in tissue protection. We speculated therefore, that the IRR might be critically involved in the action of ketamine on neuropathic pain. To evaluate this, we studied the effects of ketamine and ARA 290 on acute pain, side effects, and allodynia following a spared nerve injury model in mice lacking the β-common receptor (βcR), a structural component of the IRR. Ketamine (50 mg/kg) and ARA 290 (30 µg/kg) produced divergent effects on acute pain: ketamine produced profound antinociception accompanied with psychomotor side effects, but ARA290 did not, in both normal and knock out mice. In contrast, while both drugs were antiallodynic in WT mice, they had no effect on NP in mice lacking the βcR. Together, these results show that an intact IRR is required for the effective treatment of NP with either ketamine or ARA 290, but is not involved in ketamine’s analgesic and side effects. PMID:23936499

  19. Normal hematopoiesis and lack of β-catenin activation in osteoblasts of patients and mice harboring Lrp5 gain of function mutations

    DEFF Research Database (Denmark)

    Galan-Diez, Marta; Isa, Adiba; Ponzetti, Marco

    2016-01-01

    of hematopoiesis and leukemogenic properties of β-catenin activation in osteoblasts, that lead to development of acute myeloid leukemia (AML). Using mice with gain-of-function (GOF) Lrp5 alleles (Lrp5(A214V)) that recapitulate the human high bone mass (HBM) phenotype, as well as patients with the T253I HBM Lrp5...... mutation, we show here that Lrp5 GOF mutations in both humans and mice do not activate β-catenin signaling in osteoblasts. Consistent with a lack of β-catenin activation in their osteoblasts, Lrp5(A214V) mice have normal trilinear hematopoiesis. In contrast to leukemic mice with constitutive activation...... of β-catenin in osteoblasts (Ctnnb1(CAosb)), accumulation of early myeloid progenitors, a characteristic of AML, myeloid-blasts in blood, and segmented neutrophils or dysplastic megakaryocytes in the bone marrow, are not observed in Lrp5(A214V) mice. Likewise, peripheral blood count analysis in HBM...

  20. Mice lacking glutamate carboxypeptidase II develop normally, but are less susceptible to traumatic brain injury.

    Science.gov (United States)

    Gao, Yang; Xu, Siyi; Cui, Zhenwen; Zhang, Mingkun; Lin, Yingying; Cai, Lei; Wang, Zhugang; Luo, Xingguang; Zheng, Yan; Wang, Yong; Luo, Qizhong; Jiang, Jiyao; Neale, Joseph H; Zhong, Chunlong

    2015-07-01

    Glutamate carboxypeptidase II (GCPII) is a transmembrane zinc metallopeptidase found mainly in the nervous system, prostate and small intestine. In the nervous system, glia-bound GCPII mediates the hydrolysis of the neurotransmitter N-acetylaspartylglutamate (NAAG) into glutamate and N-acetylaspartate. Inhibition of GCPII has been shown to attenuate excitotoxicity associated with enhanced glutamate transmission under pathological conditions. However, different strains of mice lacking the GCPII gene are reported to exhibit striking phenotypic differences. In this study, a GCPII gene knockout (KO) strategy involved removing exons 3-5 of GCPII. This generated a new GCPII KO mice line with no overt differences in standard neurological behavior compared to their wild-type (WT) littermates. However, GCPII KO mice were significantly less susceptible to moderate traumatic brain injury (TBI). GCPII gene KO significantly lessened neuronal degeneration and astrocyte damage in the CA2 and CA3 regions of the hippocampus 24 h after moderate TBI. In addition, GCPII gene KO reduced TBI-induced deficits in long-term spatial learning/memory tested in the Morris water maze and motor balance tested via beam walking. Knockout of the GCPII gene is not embryonic lethal and affords histopathological protection with improved long-term behavioral outcomes after TBI, a result that further validates GCPII as a target for drug development consistent with results from studies using GCPII peptidase inhibitors. © 2015 International Society for Neurochemistry.

  1. Mice lacking natural killer T cells are more susceptible to metabolic alterations following high fat diet feeding.

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    Brittany V Martin-Murphy

    Full Text Available Current estimates suggest that over one-third of the adult population has metabolic syndrome and three-fourths of the obese population has non-alcoholic fatty liver disease (NAFLD. Inflammation in metabolic tissues has emerged as a universal feature of obesity and its co-morbidities, including NAFLD. Natural Killer T (NKT cells are a subset of innate immune cells that abundantly reside within the liver and are readily activated by lipid antigens. There is general consensus that NKT cells are pivotal regulators of inflammation; however, disagreement exists as to whether NKT cells exert pathogenic or suppressive functions in obesity. Here we demonstrate that CD1d(-/- mice, which lack NKT cells, were more susceptible to weight gain and fatty liver following high fat diet (HFD feeding. Compared with their WT counterparts, CD1d(-/- mice displayed increased adiposity and greater induction of inflammatory genes in the liver suggestive of the precursors of NAFLD. Calorimetry studies revealed a significant increase in food intake and trends toward decreased metabolic rate and activity in CD1d(-/- mice compared with WT mice. Based on these findings, our results suggest that NKT cells play a regulatory role that helps to prevent diet-induced obesity and metabolic dysfunction and may play an important role in mechanisms governing cross-talk between metabolism and the immune system to regulate energy balance and liver health.

  2. Hematopoietic Kit Deficiency, rather than Lack of Mast Cells, Protects Mice from Obesity and Insulin Resistance.

    Science.gov (United States)

    Gutierrez, Dario A; Muralidhar, Sathya; Feyerabend, Thorsten B; Herzig, Stephan; Rodewald, Hans-Reimer

    2015-05-05

    Obesity, insulin resistance, and related pathologies are associated with immune-mediated chronic inflammation. Kit mutant mice are protected from diet-induced obesity and associated co-morbidities, and this phenotype has previously been attributed to their lack of mast cells. We performed a comprehensive metabolic analysis of Kit-dependent Kit(W/Wv) and Kit-independent Cpa3(Cre/+) mast-cell-deficient mouse strains, employing diet-induced or genetic (Lep(Ob/Ob) background) models of obesity. Our results show that mast cell deficiency, in the absence of Kit mutations, plays no role in the regulation of weight gain or insulin resistance. Moreover, we provide evidence that the metabolic phenotype observed in Kit mutant mice, while independent of mast cells, is immune regulated. Our data underscore the value of definitive mast cell deficiency models to conclusively test the involvement of this enigmatic cell in immune-mediated pathologies and identify Kit as a key hematopoietic factor in the pathogenesis of metabolic syndrome. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Abnormal Cardiac Autonomic Regulation in Mice Lacking ASIC3

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    Ching-Feng Cheng

    2014-01-01

    Full Text Available Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3 is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3−/− mice. Asic3−/− mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3−/− mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3−/− mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases.

  4. Alterations in gene expression in mutant amyloid precursor protein transgenic mice lacking Niemann-Pick type C1 protein.

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    Mahua Maulik

    Full Text Available Niemann-Pick type C (NPC disease, a rare autosomal recessive disorder caused mostly by mutation in NPC1 gene, is pathologically characterized by the accumulation of free cholesterol in brain and other tissues. This is accompanied by gliosis and loss of neurons in selected brain regions, including the cerebellum. Recent studies have shown that NPC disease exhibits intriguing parallels with Alzheimer's disease, including the presence of neurofibrillary tangles and increased levels of amyloid precursor protein (APP-derived β-amyloid (Aβ peptides in vulnerable brain neurons. To evaluate the role of Aβ in NPC disease, we determined the gene expression profile in selected brain regions of our recently developed bigenic ANPC mice, generated by crossing APP transgenic (Tg mice with heterozygous Npc1-deficient mice. The ANPC mice exhibited exacerbated neuronal and glial pathology compared to other genotypes [i.e., APP-Tg, double heterozygous (Dhet, Npc1-null and wild-type mice]. Analysis of expression profiles of 86 selected genes using real-time RT-PCR arrays showed a wide-spectrum of alterations in the four genotypes compared to wild-type controls. The changes observed in APP-Tg and Dhet mice are limited to only few genes involved mostly in the regulation of cholesterol metabolism, whereas Npc1-null and ANPC mice showed alterations in the expression profiles of a number of genes regulating cholesterol homeostasis, APP metabolism, vesicular trafficking and cell death mechanism in both hippocampus and cerebellum compared to wild-type mice. Intriguingly, ANPC and Npc1-null mice, with some exceptions, exhibited similar changes, although more genes were differentially expressed in the affected cerebellum than the relatively spared hippocampus. The altered gene profiles were found to match with the corresponding protein levels. These results suggest that lack of Npc1 protein can alter the expression profile of selected transcripts as well as proteins, and

  5. Altered thalamocortical rhythmicity and connectivity in mice lacking CaV3.1 T-type Ca2+ channels in unconsciousness

    Science.gov (United States)

    Choi, Soonwook; Yu, Eunah; Lee, Seongwon; Llinás, Rodolfo R.

    2015-01-01

    In unconscious status (e.g., deep sleep and anesthetic unconsciousness) where cognitive functions are not generated there is still a significant level of brain activity present. Indeed, the electrophysiology of the unconscious brain is characterized by well-defined thalamocortical rhythmicity. Here we address the ionic basis for such thalamocortical rhythms during unconsciousness. In particular, we address the role of CaV3.1 T-type Ca2+ channels, which are richly expressed in thalamic neurons. Toward this aim, we examined the electrophysiological and behavioral phenotypes of mice lacking CaV3.1 channels (CaV3.1 knockout) during unconsciousness induced by ketamine or ethanol administration. Our findings indicate that CaV3.1 KO mice displayed attenuated low-frequency oscillations in thalamocortical loops, especially in the 1- to 4-Hz delta band, compared with control mice (CaV3.1 WT). Intriguingly, we also found that CaV3.1 KO mice exhibited augmented high-frequency oscillations during unconsciousness. In a behavioral measure of unconsciousness dynamics, CaV3.1 KO mice took longer to fall into the unconscious state than controls. In addition, such unconscious events had a shorter duration than those of control mice. The thalamocortical interaction level between mediodorsal thalamus and frontal cortex in CaV3.1 KO mice was significantly lower, especially for delta band oscillations, compared with that of CaV3.1 WT mice, during unconsciousness. These results suggest that the CaV3.1 channel is required for the generation of a given set of thalamocortical rhythms during unconsciousness. Further, that thalamocortical resonant neuronal activity supported by this channel is important for the control of vigilance states. PMID:26056284

  6. Lack of adrenomedullin results in microbiota changes and aggravates azoxymethane and dextran sulfate sodium-induced colitis in mice

    Directory of Open Access Journals (Sweden)

    Sonia Martinez-Herrero

    2016-11-01

    Full Text Available The link between intestinal inflammation, microbiota, and colorectal cancer (CRC is intriguing and the potential underlying mechanisms remain unknown. Here we evaluate the influence of adrenomedullin (AM in microbiota composition and its impact on colitis with an inducible knockout (KO mouse model for AM. Microbiota composition was analyzed in KO and wild type (WT mice by pyrosequencing. Colitis was induced in mice by administration of azoxymethane (AOM followed by dextran sulfate sodium (DSS in the drinking water. Colitis was evaluated using a clinical symptoms index, histopathological analyses, and qRT-PCR. Abrogation of the adm gene in the whole body was confirmed by PCR and qRT-PCR. KO mice exhibit significant changes in colonic microbiota: higher proportion of δ-Proteobacteria class; of Coriobacteriales order; and of other families and genera was observed in KO feces. Meanwhile these mice had a lower proportion of beneficial bacteria, such as Lactobacillus gasseri and Bifidobacterium choerinum. TLR4 gene expression was higher (p<0.05 in KO animals. AM deficient mice treated with DSS exhibited a significantly worse colitis with profound weight loss, severe diarrhea, rectal bleeding, colonic inflammation, edema, infiltration, crypt destruction, and higher levels of pro-inflammatory cytokines. No changes were observed in the expression levels of adhesion molecules. In conclusion, we have shown that lack of AM leads to changes in gut microbiota population and in a worsening of colitis conditions, suggesting that endogenous AM is a protective mediator in this pathology.

  7. Normal hematopoiesis and lack of β-catenin activation in osteoblasts of patients and mice harboring Lrp5 gain-of-function mutations.

    Science.gov (United States)

    Galán-Díez, Marta; Isa, Adiba; Ponzetti, Marco; Nielsen, Morten Frost; Kassem, Moustapha; Kousteni, Stavroula

    2016-03-01

    Osteoblasts are emerging regulators of myeloid malignancies since genetic alterations in them, such as constitutive activation of β-catenin, instigate their appearance. The LDL receptor-related protein 5 (LRP5), initially proposed to be a co-receptor for Wnt proteins, in fact favors bone formation by suppressing gut-serotonin synthesis. This function of Lrp5 occurring in the gut is independent of β-catenin activation in osteoblasts. However, it is unknown whether Lrp5 can act directly in osteoblast to influence other functions that require β-catenin signaling, particularly, the deregulation of hematopoiesis and leukemogenic properties of β-catenin activation in osteoblasts, that lead to development of acute myeloid leukemia (AML). Using mice with gain-of-function (GOF) Lrp5 alleles (Lrp5(A214V)) that recapitulate the human high bone mass (HBM) phenotype, as well as patients with the T253I HBM Lrp5 mutation, we show here that Lrp5 GOF mutations in both humans and mice do not activate β-catenin signaling in osteoblasts. Consistent with a lack of β-catenin activation in their osteoblasts, Lrp5(A214V) mice have normal trilinear hematopoiesis. In contrast to leukemic mice with constitutive activation of β-catenin in osteoblasts (Ctnnb1(CAosb)), accumulation of early myeloid progenitors, a characteristic of AML, myeloid-blasts in blood, and segmented neutrophils or dysplastic megakaryocytes in the bone marrow, are not observed in Lrp5(A214V) mice. Likewise, peripheral blood count analysis in HBM patients showed normal hematopoiesis, normal percentage of myeloid cells, and lack of anemia. We conclude that Lrp5 GOF mutations do not activate β-catenin signaling in osteoblasts. As a result, myeloid lineage differentiation is normal in HBM patients and mice. This article is part of a Special Issue entitled: Tumor Microenvironment Regulation of Cancer Cell Survival, Metastasis, Inflammation, and Immune Surveillance edited by Peter Ruvolo and Gregg L. Semenza. Published

  8. Different effects of bisphenol-A on memory behavior and synaptic modification in intact and estrogen-deprived female mice.

    Science.gov (United States)

    Xu, Xiaohong; Gu, Ting; Shen, Qiaoqiao

    2015-03-01

    Bisphenol-A (BPA) has the capability of interfering with the effects of estrogens on modulating brain function. The purpose of this study was to investigate the effects of BPA on memory and synaptic modification in the hippocampus of female mice under different levels of cycling estrogen. BPA exposure (40, 400 μg/kg/day) for 8 weeks did not affect spatial memory and passive avoidance task of gonadally intact mice but improved ovariectomy (Ovx)-induced memory impairment, whereas co-exposure of BPA with estradiol benzoate (EB) diminished the rescue effect of EB on memory behavior of Ovx mice. The results of morphometric measurement showed that BPA positively modified the synaptic interface structure and increased the synaptic density of CA1 pyramidal cell in the hippocampus of Ovx females, but inhibited the enhancement of EB on synaptic modification and synaptogenesis of Ovx mice. Furthermore, BPA up-regulated synaptic proteins synapsin I and PSD-95 and NMDA receptor NR2B but inhibited EB-induced increase in PSD-95 and NR2B in the hippocampus of Ovx mice. These results suggest that BPA interfered with normal hormonal regulation in synaptic plasticity and memory of female mice as a potent estrogen mimetic and as a disruptor of estrogen under various concentrations of cycling estrogen. © 2014 International Society for Neurochemistry.

  9. Mice lacking mPGES-1 are resistant to lithium-induced polyuria.

    Science.gov (United States)

    Jia, Zhanjun; Wang, Haiping; Yang, Tianxin

    2009-12-01

    Cyclooxygenase-2 activity is required for the development of lithium-induced polyuria. However, the involvement of a specific, terminal prostaglandin (PG) isomerase has not been evaluated. The present study was undertaken to assess lithium-induced polyuria in mice deficient in microsomal prostaglandin E synthase-1 (mPGES-1). A 2-wk administration of LiCl (4 mmol.kg(-1).day(-1) ip) in mPGES-1 +/+ mice led to a marked polyuria with hyposmotic urine. This was associated with elevated renal mPGES-1 protein expression and increased urine PGE(2) excretion. In contrast, mPGES-1 -/- mice were largely resistant to lithium-induced polyuria and a urine concentrating defect, accompanied by nearly complete blockade of high urine PGE(2) and cAMP output. Immunoblotting, immunohistochemistry, and quantitative (q) RT-PCR consistently detected a significant decrease in aquaporin-2 (AQP2) protein expression in both the renal cortex and medulla of lithium-treated +/+ mice. This decrease was significantly attenuated in the -/- mice. qRT-PCR detected similar patterns of changes in AQP2 mRNA in the medulla but not in the cortex. Similarly, the total protein abundance of the Na-K-2Cl cotransporter (NKCC2) in the medulla but not in the cortex of the +/+ mice was significantly reduced by lithium treatment. In contrast, the dowregulation of renal medullary NKCC2 expression was significantly attenuated in the -/- mice. We conclude that mPGES-1-derived PGE(2) mediates lithium-induced polyuria likely via inhibition of AQP2 and NKCC2 expression.

  10. Minor abnormalities of testis development in mice lacking the gene encoding the MAPK signalling component, MAP3K1.

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    Nick Warr

    2011-05-01

    Full Text Available In mammals, the Y chromosome is a dominant male determinant, causing the bipotential gonad to develop as a testis. Recently, cases of familial and spontaneous 46,XY disorders of sex development (DSD have been attributed to mutations in the human gene encoding mitogen-activated protein kinase kinase kinase 1, MAP3K1, a component of the mitogen-activated protein kinase (MAPK signal transduction pathway. In individuals harbouring heterozygous mutations in MAP3K1, dysregulation of MAPK signalling was observed in lymphoblastoid cell lines, suggesting a causal role for these mutations in disrupting XY sexual development. Mice lacking the cognate gene, Map3k1, are viable and exhibit the eyes open at birth (EOB phenotype on a mixed genetic background, but on the C57BL/6J genetic background most mice die at around 14.5 dpc due to a failure of erythropoiesis in the fetal liver. However, no systematic examination of sexual development in Map3k1-deficient mice has been described, an omission that is especially relevant in the case of C57BL/6J, a genetic background that is sensitized to disruptions to testis determination. Here, we report that on a mixed genetic background mice lacking Map3k1 are fertile and exhibit no overt abnormalities of testis development. On C57BL/6J, significant non-viability is observed with very few animals surviving to adulthood. However, an examination of development in Map3k1-deficient XY embryos on this genetic background revealed no significant defects in testis determination, although minor abnormalities were observed, including an increase in gonadal length. Based on these observations, we conclude that MAP3K1 is not required for mouse testis determination. We discuss the significance of these data for the functional interpretation of sex-reversing MAP3K1 mutations in humans.

  11. Synapsin II is involved in the molecular pathway of lithium treatment in bipolar disorder.

    Directory of Open Access Journals (Sweden)

    Cristiana Cruceanu

    Full Text Available Bipolar disorder (BD is a debilitating psychiatric condition with a prevalence of 1-2% in the general population that is characterized by severe episodic shifts in mood ranging from depressive to manic episodes. One of the most common treatments is lithium (Li, with successful response in 30-60% of patients. Synapsin II (SYN2 is a neuronal phosphoprotein that we have previously identified as a possible candidate gene for the etiology of BD and/or response to Li treatment in a genome-wide linkage study focusing on BD patients characterized for excellent response to Li prophylaxis. In the present study we investigated the role of this gene in BD, particularly as it pertains to Li treatment. We investigated the effect of lithium treatment on the expression of SYN2 in lymphoblastoid cell lines from patients characterized as excellent Li-responders, non-responders, as well as non-psychiatric controls. Finally, we sought to determine if Li has a cell-type-specific effect on gene expression in neuronal-derived cell lines. In both in vitro models, we found SYN2 to be modulated by the presence of Li. By focusing on Li-responsive BD we have identified a potential mechanism for Li response in some patients.

  12. Mice lacking the conserved transcription factor Grainyhead-like 3 (Grhl3) display increased apposition of the frontal and parietal bones during embryonic development.

    Science.gov (United States)

    Goldie, Stephen J; Arhatari, Benedicta D; Anderson, Peter; Auden, Alana; Partridge, Darren D; Jane, Stephen M; Dworkin, Sebastian

    2016-10-18

    Increased apposition of the frontal and parietal bones of the skull during embryogenesis may be a risk factor for the subsequent development of premature skull fusion, or craniosynostosis. Human craniosynostosis is a prevalent, and often serious embryological and neonatal pathology. Other than known mutations in a small number of contributing genes, the aetiology of craniosynostosis is largely unknown. Therefore, the identification of novel genes which contribute to normal skull patterning, morphology and premature suture apposition is imperative, in order to fully understand the genetic regulation of cranial development. Using advanced imaging techniques and quantitative measurement, we show that genetic deletion of the highly-conserved transcription factor Grainyhead-like 3 (Grhl3) in mice (Grhl3 -/- ) leads to decreased skull size, aberrant skull morphology and premature apposition of the coronal sutures during embryogenesis. Furthermore, Grhl3 -/- mice also present with premature collagen deposition and osteoblast alignment at the sutures, and the physical interaction between the developing skull, and outermost covering of the brain (the dura mater), as well as the overlying dermis and subcutaneous tissue, appears compromised in embryos lacking Grhl3. Although Grhl3 -/- mice die at birth, we investigated skull morphology and size in adult animals lacking one Grhl3 allele (heterozygous; Grhl3 +/- ), which are viable and fertile. We found that these adult mice also present with a smaller cranial cavity, suggestive of post-natal haploinsufficiency in the context of cranial development. Our findings show that our Grhl3 mice present with increased apposition of the frontal and parietal bones, suggesting that Grhl3 may be involved in the developmental pathogenesis of craniosynostosis.

  13. Depressed levels of prostaglandin F2α in mice lacking Akr1b7 increase basal adiposity and predispose to diet-induced obesity.

    Science.gov (United States)

    Volat, Fanny E; Pointud, Jean-Christophe; Pastel, Emilie; Morio, Béatrice; Sion, Benoit; Hamard, Ghislaine; Guichardant, Michel; Colas, Romain; Lefrançois-Martinez, Anne-Marie; Martinez, Antoine

    2012-11-01

    Negative regulators of white adipose tissue (WAT) expansion are poorly documented in vivo. Prostaglandin F(2α) (PGF(2α)) is a potent antiadipogenic factor in cultured preadipocytes, but evidence for its involvement in physiological context is lacking. We previously reported that Akr1b7, an aldo-keto reductase enriched in adipose stromal vascular fraction but absent from mature adipocytes, has antiadipogenic properties possibly supported by PGF(2α) synthase activity. To test whether lack of Akr1b7 could influence WAT homeostasis in vivo, we generated Akr1b7(-/-) mice in 129/Sv background. Akr1b7(-/-) mice displayed excessive basal adiposity resulting from adipocyte hyperplasia/hypertrophy and exhibited greater sensitivity to diet-induced obesity. Following adipose enlargement and irrespective of the diet, they developed liver steatosis and progressive insulin resistance. Akr1b7 loss was associated with decreased PGF(2α) WAT contents. Cloprostenol (PGF(2α) agonist) administration to Akr1b7(-/-) mice normalized WAT expansion by affecting both de novo adipocyte differentiation and size. Treatment of 3T3-L1 adipocytes and Akr1b7(-/-) mice with cloprostenol suggested that decreased adipocyte size resulted from inhibition of lipogenic gene expression. Hence, Akr1b7 is a major regulator of WAT development through at least two PGF(2α)-dependent mechanisms: inhibition of adipogenesis and lipogenesis. These findings provide molecular rationale to explore the status of aldo-keto reductases in dysregulations of adipose tissue homeostasis.

  14. Behavioural endophenotypes in mice lacking the auxiliary GABAB receptor subunit KCTD16.

    Science.gov (United States)

    Cathomas, Flurin; Sigrist, Hannes; Schmid, Luca; Seifritz, Erich; Gassmann, Martin; Bettler, Bernhard; Pryce, Christopher R

    2017-01-15

    Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain and is implicated in the pathophysiology of a number of neuropsychiatric disorders. The GABA B receptors are G-protein coupled receptors consisting of principle subunits and auxiliary potassium channel tetramerization domain (KCTD) subunits. The KCTD subunits 8, 12, 12b and 16 are cytosolic proteins that determine the kinetics of the GABA B receptor response. Previously, we demonstrated that Kctd12 null mutant mice (Kctd12 -/- ) exhibit increased auditory fear learning and that Kctd12 +/- mice show altered circadian activity, as well as increased intrinsic excitability in hippocampal pyramidal neurons. KCTD16 has been demonstrated to influence neuronal excitability by regulating GABA B receptor-mediated gating of postsynaptic ion channels. In the present study we investigated for behavioural endophenotypes in Kctd16 -/- and Kctd16 +/- mice. Compared with wild-type (WT) littermates, auditory and contextual fear conditioning were normal in both Kctd16 -/- and Kctd16 +/- mice. When fear memory was tested on the following day, Kctd16 -/- mice exhibited less extinction of auditory fear memory relative to WT and Kctd16 +/- mice, as well as more contextual fear memory relative to WT and, in particular, Kctd16 +/- mice. Relative to WT, both Kctd16 +/- and Kctd16 -/- mice exhibited normal circadian activity. This study adds to the evidence that auxillary KCTD subunits of GABA B receptors contribute to the regulation of behaviours that could constitute endophenotypes for hyper-reactivity to aversive stimuli in neuropsychiatric disorders. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Evaluating mice lacking serum carboxylesterase as a behavioral model for nerve agent intoxication.

    Science.gov (United States)

    Dunn, Emily N; Ferrara-Bowens, Teresa M; Chachich, Mark E; Honnold, Cary L; Rothwell, Cristin C; Hoard-Fruchey, Heidi M; Lesyna, Catherine A; Johnson, Erik A; Cerasoli, Douglas M; McDonough, John H; Cadieux, C Linn

    2018-06-07

    Mice and other rodents are typically utilized for chemical warfare nerve agent research. Rodents have large amounts of carboxylesterase in their blood, while humans do not. Carboxylesterase nonspecifically binds to and detoxifies nerve agent. The presence of this natural bioscavenger makes mice and other rodents poor models for studies identifying therapeutics to treat humans exposed to nerve agents. To obviate this problem, a serum carboxylesterase knockout (Es1 KO) mouse was created. In this study, Es1 KO and wild type (WT) mice were assessed for differences in gene expression, nerve agent (soman; GD) median lethal dose (MLD) values, and behavior prior to and following nerve agent exposure. No expression differences were detected between Es1 KO and WT mice in more than 34 000 mouse genes tested. There was a significant difference between Es1 KO and WT mice in MLD values, as the MLD for GD-exposed WT mice was significantly higher than the MLD for GD-exposed Es1 KO mice. Behavioral assessments of Es1 KO and WT mice included an open field test, a zero maze, a Barnes maze, and a sucrose preference test (SPT). While sex differences were observed in various measures of these tests, overall, Es1 KO mice behaved similarly to WT mice. The two genotypes also showed virtually identical neuropathological changes following GD exposure. Es1 KO mice appear to have an enhanced susceptibility to GD toxicity while retaining all other behavioral and physiological responses to this nerve agent, making the Es1 KO mouse a more human-like model for nerve agent research.

  16. Dwarfism and early death in mice lacking C-type natriuretic peptide

    Science.gov (United States)

    Chusho, Hideki; Tamura, Naohisa; Ogawa, Yoshihiro; Yasoda, Akihiro; Suda, Michio; Miyazawa, Takashi; Nakamura, Kenji; Nakao, Kazuki; Kurihara, Tatsuya; Komatsu, Yasato; Itoh, Hiroshi; Tanaka, Kiyoshi; Saito, Yoshihiko; Katsuki, Motoya; Nakao, Kazuwa

    2001-01-01

    Longitudinal bone growth is determined by endochondral ossification that occurs as chondrocytes in the cartilaginous growth plate undergo proliferation, hypertrophy, cell death, and osteoblastic replacement. The natriuretic peptide family consists of three structurally related endogenous ligands, atrial, brain, and C-type natriuretic peptides (ANP, BNP, and CNP), and is thought to be involved in a variety of homeostatic processes. To investigate the physiological significance of CNP in vivo, we generated mice with targeted disruption of CNP (Nppc−/− mice). The Nppc−/− mice show severe dwarfism as a result of impaired endochondral ossification. They are all viable perinatally, but less than half can survive during postnatal development. The skeletal phenotypes are histologically similar to those seen in patients with achondroplasia, the most common genetic form of human dwarfism. Targeted expression of CNP in the growth plate chondrocytes can rescue the skeletal defect of Nppc−/− mice and allow their prolonged survival. This study demonstrates that CNP acts locally as a positive regulator of endochondral ossification in vivo and suggests its pathophysiological and therapeutic implication in some forms of skeletal dysplasia. PMID:11259675

  17. Somatostatin receptor 1 and 5 double knockout mice mimic neurochemical changes of Huntington's disease transgenic mice.

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    Padmesh S Rajput

    Full Text Available Selective degeneration of medium spiny neurons and preservation of medium sized aspiny interneurons in striatum has been implicated in excitotoxicity and pathophysiology of Huntington's disease (HD. However, the molecular mechanism for the selective sparing of medium sized aspiny neurons and vulnerability of projection neurons is still elusive. The pathological characteristic of HD is an extensive reduction of the striatal mass, affecting caudate putamen. Somatostatin (SST positive neurons are selectively spared in HD and Quinolinic acid/N-methyl-D-aspartic acid induced excitotoxicity, mimic the model of HD. SST plays neuroprotective role in excitotoxicity and the biological effects of SST are mediated by five somatostatin receptor subtypes (SSTR1-5.To delineate subtype selective biological responses we have here investigated changes in SSTR1 and 5 double knockout mice brain and compared with HD transgenic mouse model (R6/2. Our study revealed significant loss of dopamine and cAMP regulated phosphoprotein of 32 kDa (DARPP-32 and comparable changes in SST, N-methyl-D-aspartic acid receptors subtypes, calbindin and brain nitric oxide synthase expression as well as in key signaling proteins including calpain, phospho-extracellular-signal-regulated kinases1/2, synapsin-IIa, protein kinase C-α and calcineurin in SSTR1/5(-/- and R6/2 mice. Conversely, the expression of somatostatin receptor subtypes, enkephalin and phosphatidylinositol 3-kinases were strain specific. SSTR1/5 appears to be important in regulating NMDARs, DARPP-32 and signaling molecules in similar fashion as seen in HD transgenic mice.This is the first comprehensive description of disease related changes upon ablation of G- protein coupled receptor gene. Our results indicate that SST and SSTRs might play an important role in regulation of neurodegeneration and targeting this pathway can provide a novel insight in understanding the pathophysiology of Huntington's disease.

  18. Niemann-Pick C1-deficient mice lacking sterol O-acyltransferase 2 have less hepatic cholesterol entrapment and improved liver function.

    Science.gov (United States)

    Lopez, Adam M; Jones, Ryan Dale; Repa, Joyce J; Turley, Stephen D

    2018-06-07

    Cholesteryl esters are generated at multiple sites in the body by sterol O-acyltransferase 1 (SOAT1) or sterol O-acyltransferase 2 (SOAT2) in various cell types, and lecithin cholesterol acyltransferase (LCAT) in plasma. Esterified cholesterol (EC) and triacylglycerol (TAG) contained in lipoproteins cleared from the circulation via receptor-mediated or bulk-phase endocytosis are hydrolyzed by lysosomal acid lipase (LAL) within the late endosomal/lysosomal (E/L) compartment. Then, through the successive actions of Niemann-Pick C2 (NPC2) and Niemann-Pick C1 (NPC1), unesterified cholesterol (UC) is exported from the E/L compartment to the cytosol. Mutations in either NPC1 or NPC2 lead to continuing entrapment of UC in all organs, resulting in multisystem disease which includes hepatic dysfunction and in some cases liver failure. These studies investigated primarily whether elimination of SOAT2 in NPC1-deficient mice impacted hepatic UC sequestration, inflammation, and transaminase activities. Measurements were made in 7 wk-old mice fed a low-cholesterol chow diet or one enriched with cholesterol starting 2 wk before study. In the chow-fed mice, NPC1:SOAT2 double knockouts, compared to their littermates lacking only NPC1, had 20% less liver mass, 28% lower hepatic UC concentrations, and plasma ALT and AST activities that were decreased by 48% and 36%, respectively. mRNA expression levels for several markers of inflammation were all significantly lower in the NPC1 mutants lacking SOAT2. The existence of a new class of potent and selective SOAT2 inhibitors provides an opportunity for exploring if suppression of this enzyme could potentially become an adjunctive therapy for liver disease in NPC1 deficiency.

  19. Aberrant Bone Density in Aging Mice Lacking the Adenosine Transporter ENT1

    Science.gov (United States)

    Hinton, David J.; McGee-Lawrence, Meghan E.; Lee, Moonnoh R.; Kwong, Hoi K.; Westendorf, Jennifer J.; Choi, Doo-Sup

    2014-01-01

    Adenosine is known to regulate bone production and resorption in humans and mice. Type 1 equilibrative nucleoside transporter (ENT1) is responsible for the majority of adenosine transport across the plasma membrane and is ubiquitously expressed in both humans and mice. However, the contribution of ENT1-mediated adenosine levels has not been studied in bone remodeling. With the recent identification of the importance of adenosine signaling in bone homeostasis, it is essential to understand the role of ENT1 to develop novel therapeutic compounds for bone disorders. Here we examined the effect of ENT1 deletion on bone density using X-ray, dual energy X-ray absorptiometry and micro-computerized tomography analysis. Our results show that bone density and bone mineral density is reduced in the lower thoracic and lumbar spine as well as the femur of old ENT1 null mice (>7 months) compared to wild-type littermates. Furthermore, we found increased mRNA expression of tartrate-resistant acid phosphatase (TRAP), an osteoclast marker, in isolated long bones from 10 month old ENT1 null mice compared to wild-type mice. In addition, aged ENT1 null mice displayed severe deficit in motor coordination and locomotor activity, which might be attributed to dysregulated bone density. Overall, our study suggests that ENT1-regulated adenosine signaling plays an essential role in lumbar spine and femur bone density. PMID:24586402

  20. Aberrant bone density in aging mice lacking the adenosine transporter ENT1.

    Directory of Open Access Journals (Sweden)

    David J Hinton

    Full Text Available Adenosine is known to regulate bone production and resorption in humans and mice. Type 1 equilibrative nucleoside transporter (ENT1 is responsible for the majority of adenosine transport across the plasma membrane and is ubiquitously expressed in both humans and mice. However, the contribution of ENT1-mediated adenosine levels has not been studied in bone remodeling. With the recent identification of the importance of adenosine signaling in bone homeostasis, it is essential to understand the role of ENT1 to develop novel therapeutic compounds for bone disorders. Here we examined the effect of ENT1 deletion on bone density using X-ray, dual energy X-ray absorptiometry and micro-computerized tomography analysis. Our results show that bone density and bone mineral density is reduced in the lower thoracic and lumbar spine as well as the femur of old ENT1 null mice (>7 months compared to wild-type littermates. Furthermore, we found increased mRNA expression of tartrate-resistant acid phosphatase (TRAP, an osteoclast marker, in isolated long bones from 10 month old ENT1 null mice compared to wild-type mice. In addition, aged ENT1 null mice displayed severe deficit in motor coordination and locomotor activity, which might be attributed to dysregulated bone density. Overall, our study suggests that ENT1-regulated adenosine signaling plays an essential role in lumbar spine and femur bone density.

  1. Skeletal development of mice lacking bone sialoprotein (BSP--impairment of long bone growth and progressive establishment of high trabecular bone mass.

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    Wafa Bouleftour

    Full Text Available Adult Ibsp-knockout mice (BSP-/- display shorter stature, lower bone turnover and higher trabecular bone mass than wild type, the latter resulting from impaired bone resorption. Unexpectedly, BSP knockout also affects reproductive behavior, as female mice do not construct a proper "nest" for their offsprings. Multiple crossing experiments nonetheless indicated that the shorter stature and lower weight of BSP-/- mice, since birth and throughout life, as well as their shorter femur and tibia bones are independent of the genotype of the mothers, and thus reflect genetic inheritance. In BSP-/- newborns, µCT analysis revealed a delay in membranous primary ossification, with wider cranial sutures, as well as thinner femoral cortical bone and lower tissue mineral density, reflected in lower expression of bone formation markers. However, trabecular bone volume and osteoclast parameters of long bones do not differ between genotypes. Three weeks after birth, osteoclast number and surface drop in the mutants, concomitant with trabecular bone accumulation. The growth plates present a thinner hypertrophic zone in newborns with lower whole bone expression of IGF-1 and higher IHH in 6 days old BSP-/- mice. At 3 weeks the proliferating zone is thinner and the hypertrophic zone thicker in BSP-/- than in BSP+/+ mice of either sex, maybe reflecting a combination of lower chondrocyte proliferation and impaired cartilage resorption. Six days old BSP-/- mice display lower osteoblast marker expression but higher MEPE and higher osteopontin(Opn/Runx2 ratio. Serum Opn is higher in mutants at day 6 and in adults. Thus, lack of BSP alters long bone growth and membranous/cortical primary bone formation and mineralization. Endochondral development is however normal in mutant mice and the accumulation of trabecular bone observed in adults develops progressively in the weeks following birth. Compensatory high Opn may allow normal endochondral development in BSP-/- mice

  2. Mice lacking the UbCKmit isoform of creatine kinase reveal slower spatial learning acquisition, diminished exploration and habituation, and reduced acoustic startle reflex responses.

    NARCIS (Netherlands)

    Streijger, F.; Jost, C.R.; Oerlemans, F.T.J.J.; Ellenbroek, B.A.; Cools, A.R.; Wieringa, B.; Zee, C.E.E.M. van der

    2004-01-01

    Brain-type creatine kinases B-CK (cytosolic) and UbCKmit (mitochondrial) are considered important for the maintenance and distribution of cellular energy in the central nervous system. Previously, we have demonstrated an abnormal behavioral phenotype in mice lacking the B-CK creatine kinase isoform,

  3. Characterization of spontaneous air space enlargement in mice lacking microfibrillar-associated protein 4

    DEFF Research Database (Denmark)

    Holm, Anne Trommelholt; Wulf-Johansson, Helle; Hvidsten, Svend

    2015-01-01

    to characterize the pulmonary function changes and emphysematous changes that occur in Mfap4-deficient (Mfap4(-/-)) mice. Significant changes included increases in total lung capacity and compliance, which were evident in Mfap4(-/-) mice at 6 and 8 mo but not at 3 mo of age. Using in vivo breath-hold gated...... were both significantly decreased in Mfap4(-/-) mice by 25 and 15%, respectively. The data did not support an essential role of MFAP4 in pulmonary elastic fiber organization or content but indicated increased turnover in young Mfap4(-/-) mice. However, Mfap4(-/-) mice developed a spontaneous loss...... of lung function, which was evident at 6 mo of age, and moderate air space enlargement, with emphysema-like changes....

  4. Dwarfism in Mice Lacking Collagen-binding Integrins α2β1 and α11β1 Is Caused by Severely Diminished IGF-1 Levels*

    Science.gov (United States)

    Blumbach, Katrin; Niehoff, Anja; Belgardt, Bengt F.; Ehlen, Harald W. A.; Schmitz, Markus; Hallinger, Ralf; Schulz, Jan-Niklas; Brüning, Jens C.; Krieg, Thomas; Schubert, Markus; Gullberg, Donald; Eckes, Beate

    2012-01-01

    Mice with a combined deficiency in the α2β1 and α11β1 integrins lack the major receptors for collagen I. These mutants are born with inconspicuous differences in size but develop dwarfism within the first 4 weeks of life. Dwarfism correlates with shorter, less mineralized and functionally weaker bones that do not result from growth plate abnormalities or osteoblast dysfunction. Besides skeletal dwarfism, internal organs are correspondingly smaller, indicating proportional dwarfism and suggesting a systemic cause for the overall size reduction. In accordance with a critical role of insulin-like growth factor (IGF)-1 in growth control and bone mineralization, circulating IGF-1 levels in the sera of mice lacking either α2β1 or α11β1 or both integrins were sharply reduced by 39%, 64%, or 81% of normal levels, respectively. Low hepatic IGF-1 production resulted from diminished growth hormone-releasing hormone expression in the hypothalamus and, subsequently, reduced growth hormone expression in the pituitary glands of these mice. These findings point out a novel role of collagen-binding integrin receptors in the control of growth hormone/IGF-1-dependent biological activities. Thus, coupling hormone secretion to extracellular matrix signaling via integrins represents a novel concept in the control of endocrine homeostasis. PMID:22210772

  5. Dwarfism in mice lacking collagen-binding integrins α2β1 and α11β1 is caused by severely diminished IGF-1 levels.

    Science.gov (United States)

    Blumbach, Katrin; Niehoff, Anja; Belgardt, Bengt F; Ehlen, Harald W A; Schmitz, Markus; Hallinger, Ralf; Schulz, Jan-Niklas; Brüning, Jens C; Krieg, Thomas; Schubert, Markus; Gullberg, Donald; Eckes, Beate

    2012-02-24

    Mice with a combined deficiency in the α2β1 and α11β1 integrins lack the major receptors for collagen I. These mutants are born with inconspicuous differences in size but develop dwarfism within the first 4 weeks of life. Dwarfism correlates with shorter, less mineralized and functionally weaker bones that do not result from growth plate abnormalities or osteoblast dysfunction. Besides skeletal dwarfism, internal organs are correspondingly smaller, indicating proportional dwarfism and suggesting a systemic cause for the overall size reduction. In accordance with a critical role of insulin-like growth factor (IGF)-1 in growth control and bone mineralization, circulating IGF-1 levels in the sera of mice lacking either α2β1 or α11β1 or both integrins were sharply reduced by 39%, 64%, or 81% of normal levels, respectively. Low hepatic IGF-1 production resulted from diminished growth hormone-releasing hormone expression in the hypothalamus and, subsequently, reduced growth hormone expression in the pituitary glands of these mice. These findings point out a novel role of collagen-binding integrin receptors in the control of growth hormone/IGF-1-dependent biological activities. Thus, coupling hormone secretion to extracellular matrix signaling via integrins represents a novel concept in the control of endocrine homeostasis.

  6. Ginsenoside Rg1 Ameliorates Behavioral Abnormalities and Modulates the Hippocampal Proteomic Change in Triple Transgenic Mice of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Lulin Nie

    2017-01-01

    Full Text Available Alzheimer’s disease (AD is one of the most common neurodegenerative diseases, so far, there are no effective measures to prevent and cure this deadly condition. Ginsenoside Rg1 (Rg1 was shown to improve behavioral abnormalities in AD; however, the potential mechanisms remain unclear. In this study, we pretreated 7-month-old 3xTg-AD mice for 6 weeks with Rg1 and evaluated the effects of Rg1 on the behaviors and the protein expression of hippocampal tissues. The behavioral tests showed that Rg1 could improve the memory impairment and ameliorate the depression-like behaviors of 3xTg-AD mice. Proteomic results revealed a total of 28 differentially expressed hippocampal proteins between Rg1-treated and nontreated 3xTg-AD mice. Among these proteins, complexin-2 (CPLX2, synapsin-2 (SYN2, and synaptosomal-associated protein 25 (SNP25 were significantly downregulated in the hippocampus of 3xTg-AD mice compared with the WT mice, and the treatment of Rg1 modulated the expression of CPLX2 and SNP25 in the hippocampus of 3xTg-AD mice. The expression of CPLX2, SYN2, and SNP25 was further validated by Western blot analysis. Taken together, we concluded that Rg1 could be a potential candidate drug to improve the behavioral deficits in AD via modulating the expression of the proteins (i.e., CPLX2, SYN2, and SNP25.

  7. Calcium current homeostasis and synaptic deficits in hippocampal neurons from Kelch-like 1 knockout mice

    Directory of Open Access Journals (Sweden)

    Paula Patricia Perissinotti

    2015-01-01

    Full Text Available Kelch-like 1 (KLHL1 is a neuronal actin-binding protein that modulates voltage-gated CaV2.1 (P/Q-type and CaV3.2 (α1H T-type calcium channels; KLHL1 knockdown experiments (KD cause down-regulation of both channel types and altered synaptic properties in cultured rat hippocampal neurons (Perissinotti et al., 2014. Here, we studied the effect of ablation of KLHL1 on calcium channel function and synaptic properties in cultured hippocampal neurons from KLHL1 knockout (KO mice. Western blot data showed the P/Q-type channel α1A subunit was less abundant in KO hippocampus compared to wildtype (WT; and PQ-type calcium currents were smaller in KO neurons than WT during early days in vitro, although this decrease was compensated for at late stages by increases in L-type calcium current. In contrast, T-type currents did not change in culture. However, biophysical properties and western blot analysis revealed a differential contribution of T-type channel isoforms in the KO, with CaV3.2 α1H subunit being down-regulated and CaV3.1 α1G up-regulated. Synapsin I levels were reduced in the KO hippocampus; cultured neurons displayed a concomitant reduction in synapsin I puncta and decreased miniature excitatory postsynaptic current (mEPSC frequency. In summary, genetic ablation of the calcium channel modulator resulted in compensatory mechanisms to maintain calcium current homeostasis in hippocampal KO neurons; however, synaptic alterations resulted in a reduction of excitatory synapse number, causing an imbalance of the excitatory-inhibitory synaptic input ratio favoring inhibition.

  8. Abnormal motor phenotype at adult stages in mice lacking type 2 deiodinase.

    Science.gov (United States)

    Bárez-López, Soledad; Bosch-García, Daniel; Gómez-Andrés, David; Pulido-Valdeolivas, Irene; Montero-Pedrazuela, Ana; Obregon, Maria Jesus; Guadaño-Ferraz, Ana

    2014-01-01

    Thyroid hormones have a key role in both the developing and adult central nervous system and skeletal muscle. The thyroid gland produces mainly thyroxine (T4) but the intracellular concentrations of 3,5,3'-triiodothyronine (T3; the transcriptionally active hormone) in the central nervous system and skeletal muscle are modulated by the activity of type 2 deiodinase (D2). To date no neurological syndrome has been associated with mutations in the DIO2 gene and previous studies in young and juvenile D2-knockout mice (D2KO) did not find gross neurological alterations, possibly due to compensatory mechanisms. This study aims to analyze the motor phenotype of 3-and-6-month-old D2KO mice to evaluate the role of D2 on the motor system at adult stages in which compensatory mechanisms could have failed. Motor abilities were explored by validated tests. In the footprint test, D2KO showed an altered global gait pattern (mice walked slower, with shorter strides and with a hindlimb wider base of support than wild-type mice). No differences were detected in the balance beam test. However, a reduced latency to fall was found in the rotarod, coat-hanger and four limb hanging wire tests indicating impairment on coordination and prehensile reflex and a reduction of muscle strength. In histological analyses of cerebellum and skeletal muscle, D2KO mice did not present gross structural abnormalities. Thyroid hormones levels and deiodinases activities were also determined. In D2KO mice, despite euthyroid T3 and high T4 plasma levels, T3 levels were significantly reduced in cerebral cortex (48% reduction) and skeletal muscle (33% reduction), but not in the cerebellum where other deiodinase (type 1) is expressed. The motor alterations observed in D2KO mice indicate an important role for D2 in T3 availability to maintain motor function and muscle strength. Our results suggest a possible implication of D2 in motor disorders.

  9. Abnormal motor phenotype at adult stages in mice lacking type 2 deiodinase.

    Directory of Open Access Journals (Sweden)

    Soledad Bárez-López

    Full Text Available BACKGROUND: Thyroid hormones have a key role in both the developing and adult central nervous system and skeletal muscle. The thyroid gland produces mainly thyroxine (T4 but the intracellular concentrations of 3,5,3'-triiodothyronine (T3; the transcriptionally active hormone in the central nervous system and skeletal muscle are modulated by the activity of type 2 deiodinase (D2. To date no neurological syndrome has been associated with mutations in the DIO2 gene and previous studies in young and juvenile D2-knockout mice (D2KO did not find gross neurological alterations, possibly due to compensatory mechanisms. AIM: This study aims to analyze the motor phenotype of 3-and-6-month-old D2KO mice to evaluate the role of D2 on the motor system at adult stages in which compensatory mechanisms could have failed. RESULTS: Motor abilities were explored by validated tests. In the footprint test, D2KO showed an altered global gait pattern (mice walked slower, with shorter strides and with a hindlimb wider base of support than wild-type mice. No differences were detected in the balance beam test. However, a reduced latency to fall was found in the rotarod, coat-hanger and four limb hanging wire tests indicating impairment on coordination and prehensile reflex and a reduction of muscle strength. In histological analyses of cerebellum and skeletal muscle, D2KO mice did not present gross structural abnormalities. Thyroid hormones levels and deiodinases activities were also determined. In D2KO mice, despite euthyroid T3 and high T4 plasma levels, T3 levels were significantly reduced in cerebral cortex (48% reduction and skeletal muscle (33% reduction, but not in the cerebellum where other deiodinase (type 1 is expressed. CONCLUSIONS: The motor alterations observed in D2KO mice indicate an important role for D2 in T3 availability to maintain motor function and muscle strength. Our results suggest a possible implication of D2 in motor disorders.

  10. Lack of Pannexin 1 Alters Synaptic GluN2 Subunit Composition and Spatial Reversal Learning in Mice.

    Science.gov (United States)

    Gajardo, Ivana; Salazar, Claudia S; Lopez-Espíndola, Daniela; Estay, Carolina; Flores-Muñoz, Carolina; Elgueta, Claudio; Gonzalez-Jamett, Arlek M; Martínez, Agustín D; Muñoz, Pablo; Ardiles, Álvaro O

    2018-01-01

    Long-term potentiation (LTP) and long-term depression (LTD) are two forms of synaptic plasticity that have been considered as the cellular substrate of memory formation. Although LTP has received considerable more attention, recent evidences indicate that LTD plays also important roles in the acquisition and storage of novel information in the brain. Pannexin 1 (Panx1) is a membrane protein that forms non-selective channels which have been shown to modulate the induction of hippocampal synaptic plasticity. Animals lacking Panx1 or blockade of Pannexin 1 channels precludes the induction of LTD and facilitates LTP. To evaluate if the absence of Panx1 also affects the acquisition of rapidly changing information we trained Panx1 knockout (KO) mice and wild type (WT) littermates in a visual and hidden version of the Morris water maze (MWM). We found that KO mice find the hidden platform similarly although slightly quicker than WT animals, nonetheless, when the hidden platform was located in the opposite quadrant (OQ) to the previous learned location, KO mice spent significantly more time in the previous quadrant than in the new location indicating that the absence of Panx1 affects the reversion of a previously acquired spatial memory. Consistently, we observed changes in the content of synaptic proteins critical to LTD, such as GluN2 subunits of N-methyl-D-aspartate receptors (NMDARs), which changed their contribution to synaptic plasticity in conditions of Panx1 ablation. Our findings give further support to the role of Panx1 channels on the modulation of synaptic plasticity induction, learning and memory processes.

  11. Female mice lacking cholecystokinin 1 receptors have compromised neurogenesis, and fewer dopaminergic cells in the olfactory bulb

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    Yi eSui

    2013-03-01

    Full Text Available Neurogenesis in the adult rodent brain is largely restricted to the subependymal zone (SVZ of the lateral ventricle and subgranular zone (SGZ of the dentate gyrus (DG. We examined whether cholecystokinin (CCK through actions mediated by CCK1 receptors (CCK1R is involved in regulating neurogenesis. Proliferating cells in the SVZ, measured by 5-bromo-2-deoxyuridine (BrdU injected 2 hours prior to death or by immunoreactivity against Ki67, were reduced by 37% and 42%, respectively, in female (but not male mice lacking CCK1Rs (CCK1R-/- compared to wild-type (WT. Generation of neuroblasts in the SVZ and rostral migratory stream was also affected, since the number of doublecortin (DCX-immunoreactive (ir neuroblasts in these regions decreased by 29%. In the SGZ of female CCK1R-/- mice, BrdU-positive (+ and Ki67-ir cells were reduced by 38% and 56%, respectively, while DCX-ir neuroblasts were down 80%. Subsequently, the effect of reduced SVZ/SGZ proliferation on the generation and survival of mature adult-born cells in female CCK1R-/- mice was examined. In the OB granule cell layer (GCL, the number of neuronal nuclei (NeuN-ir and calretinin-ir cells was stable compared to WT, and 42 days after BrdU injections, the number of BrdU+ cells co-expressing GABA- or NeuN-like immunoreactivity (LI was similar. Compared to WT, the granule cell layer of the DG in female CCK1R-/- mice had a similar number of calbindin-ir cells and BrdU+ cells co-expressing calbindin-LI 42 days after BrdU injections. However, the OB glomerular layer (GL of CCK1R-/- female mice had 11% fewer NeuN-ir cells, 23% less TH-ir cells, and a 38% and 29% reduction in BrdU+ cells that co-expressed TH-LI or GABA-LI, respectively. We conclude that CCK, via CCK1Rs, is involved in regulating the generation of proliferating cells and neuroblasts in the adult female mouse brain, and mechanisms are in place to maintain steady neuronal populations in the OB and DG when the rate of proliferation is

  12. Lack of caching of direct-seeded Douglas fir seeds by deer mice

    International Nuclear Information System (INIS)

    Sullivan, T.P.

    1978-01-01

    Seed caching by deer mice was investigated by radiotagging seeds in forest and clear-cut areas in coastal British Columbia. Deer mice tend to cache very few Douglas fir seeds in the fall when the seed is uniformly distributed and is at densities comparable with those used in direct-seeding programs. (author)

  13. ENU mutagenesis reveals a novel phenotype of reduced limb strength in mice lacking fibrillin 2.

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    Gaynor Miller

    2010-02-01

    Full Text Available Fibrillins 1 (FBN1 and 2 (FBN2 are components of microfibrils, microfilaments that are present in many connective tissues, either alone or in association with elastin. Marfan's syndrome and congenital contractural arachnodactyly (CCA result from dominant mutations in the genes FBN1 and FBN2 respectively. Patients with both conditions often present with specific muscle atrophy or weakness, yet this has not been reported in the mouse models. In the case of Fbn1, this is due to perinatal lethality of the homozygous null mice making measurements of strength difficult. In the case of Fbn2, four different mutant alleles have been described in the mouse and in all cases syndactyly was reported as the defining phenotypic feature of homozygotes.As part of a large-scale N-ethyl-N-nitrosourea (ENU mutagenesis screen, we identified a mouse mutant, Mariusz, which exhibited muscle weakness along with hindlimb syndactyly. We identified an amber nonsense mutation in Fbn2 in this mouse mutant. Examination of a previously characterised Fbn2-null mutant, Fbn2(fp, identified a similar muscle weakness phenotype. The two Fbn2 mutant alleles complement each other confirming that the weakness is the result of a lack of Fbn2 activity. Skeletal muscle from mutants proved to be abnormal with higher than average numbers of fibres with centrally placed nuclei, an indicator that there are some regenerating muscle fibres. Physiological tests indicated that the mutant muscle produces significantly less maximal force, possibly as a result of the muscles being relatively smaller in Mariusz mice.These findings indicate that Fbn2 is involved in integrity of structures required for strength in limb movement. As human patients with mutations in the fibrillin genes FBN1 and FBN2 often present with muscle weakness and atrophy as a symptom, Fbn2-null mice will be a useful model for examining this aspect of the disease process further.

  14. Generation of mice lacking DUF1220 protein domains

    DEFF Research Database (Denmark)

    Keeney, J G; O'Bleness, M S; Anderson, N

    2015-01-01

    associations, a function for these domains has not been described. As a first step in addressing this question, we have developed the first transgenic model of DUF1220 function by removing the single DUF1220 domain (the ancestral form) encoded in the mouse genome. In a hypothesis generating exercise...... function, and potentially suggests a role in developmental metabolism. Finally, the substantially reduced fecundity we observe associated with KO mice argues that the ancestral DUF1220 domain provides an important biological functionthat is critical to survivability and reproductive success....

  15. Testicular development in mice lacking receptors for follicle stimulating hormone and androgen.

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    Peter J O'Shaughnessy

    Full Text Available Post-natal testicular development is dependent on gonadotrophin and androgen stimulation. Follicle stimulating hormone (FSH acts through receptors (FSHR on the Sertoli cell to stimulate spermatogenesis while androgens promote testis growth through receptors (AR on the Sertoli cells, Leydig cells and peritubular myoid cells. In this study we have examined the effects on testis development of ablating FSHRs (FSHRKO mice and/or ARs ubiquitously (ARKO mice or specifically on the Sertoli cells (SCARKO mice. Cell numbers were measured using stereological methods. In ARKO mice Sertoli cell numbers were reduced at all ages from birth until adulthood. FSHR ablation also caused small reductions in Sertoli cell numbers up to day 20 with more marked effects seen in the adult. Germ cell numbers were unaffected by FSHR and/or AR ablation at birth. By day 20 ubiquitous AR or FSHR ablation caused a marked reduction in germ cell numbers with a synergistic effect of losing both receptors (germ cell numbers in FSHRKO.ARKO mice were 3% of control. Germ cell numbers in SCARKO mice were less affected. By adulthood, in contrast, clear synergistic control of germ cell numbers had become established between the actions of FSH and androgen through the Sertoli cells. Leydig cell numbers were normal on day 1 and day 5 in all groups. By day 20 and in adult animals total AR or FSHR ablation significantly reduced Leydig cell numbers but Sertoli cell specific AR ablation had no effect. Results show that, prior to puberty, development of most testicular parameters is more dependent on FSH action than androgen action mediated through the Sertoli cells although androgen action through other cells types is crucial. Post-pubertally, germ cell numbers and spermatogenesis are dependent on FSH and androgen action through the Sertoli cells.

  16. Sphingosine-1-Phosphate (S1P) Impacts Presynaptic Functions by Regulating Synapsin I Localization in the Presynaptic Compartment.

    Science.gov (United States)

    Riganti, Loredana; Antonucci, Flavia; Gabrielli, Martina; Prada, Ilaria; Giussani, Paola; Viani, Paola; Valtorta, Flavia; Menna, Elisabetta; Matteoli, Michela; Verderio, Claudia

    2016-04-20

    Growing evidence indicates that sphingosine-1-P (S1P) upregulates glutamate secretion in hippocampal neurons. However, the molecular mechanisms through which S1P enhances excitatory activity remain largely undefined. The aim of this study was to identify presynaptic targets of S1P action controlling exocytosis. Confocal analysis of rat hippocampal neurons showed that S1P applied at nanomolar concentration alters the distribution of Synapsin I (SynI), a presynaptic phosphoprotein that controls the availability of synaptic vesicles for exocytosis. S1P induced SynI relocation to extrasynaptic regions of mature neurons, as well as SynI dispersion from synaptic vesicle clusters present at axonal growth cones of developing neurons. S1P-induced SynI relocation occurred in a Ca(2+)-independent but ERK-dependent manner, likely through the activation of S1P3 receptors, as it was prevented by the S1P3 receptor selective antagonist CAY1044 and in neurons in which S1P3 receptor was silenced. Our recent evidence indicates that microvesicles (MVs) released by microglia enhance the metabolism of endogenous sphingolipids in neurons and stimulate excitatory transmission. We therefore investigated whether MVs affect SynI distribution and whether endogenous S1P could be involved in the process. Analysis of SynI immunoreactivity showed that exposure to microglial MVs induces SynI mobilization at presynaptic sites and growth cones, whereas the use of inhibitors of sphingolipid cascade identified S1P as the sphingolipid mediating SynI redistribution. Our data represent the first demonstration that S1P induces SynI mobilization from synapses, thereby indicating the phosphoprotein as a novel target through which S1P controls exocytosis. Growing evidence indicates that the bioactive lipid sphingosine and its metabolite sphingosine-1-P (S1P) stimulate excitatory transmission. While it has been recently clarified that sphingosine influences directly the exocytotic machinery by activating the

  17. Defective thrombus formation in mice lacking endogenous factor VII activating protease (FSAP).

    Science.gov (United States)

    Subramaniam, Saravanan; Thielmann, Ina; Morowski, Martina; Pragst, Ingo; Sandset, Per Morten; Nieswandt, Bernhard; Etscheid, Michael; Kanse, Sandip M

    2015-04-01

    Factor VII (FVII) activating protease (FSAP) is a circulating protease with a putative function in blood coagulation and fibrinolysis. Genetic epidemiological studies have implied a role for FSAP in carotid stenosis, stroke and thrombosis. To date, no in vivo evidence is available to support these claims. We have, for the first time, used FSAP-/- mice to define its role in thrombosis and haemostasis in vivo and to characterise the molecular mechanisms involved. FeCl3-induced arterial thrombosis in carotid and mesenteric artery revealed that the occlusion time was significantly increased in FSAP-/- mice (pendogenous FSAP impaired the formation of stable, occlusive thrombi in mice. The underlying in vivo effect of FSAP is more likely to be related to the modulation of TFPI rather than FVIIa.

  18. Lack of Pannexin 1 Alters Synaptic GluN2 Subunit Composition and Spatial Reversal Learning in Mice

    Science.gov (United States)

    Gajardo, Ivana; Salazar, Claudia S.; Lopez-Espíndola, Daniela; Estay, Carolina; Flores-Muñoz, Carolina; Elgueta, Claudio; Gonzalez-Jamett, Arlek M.; Martínez, Agustín D.; Muñoz, Pablo; Ardiles, Álvaro O.

    2018-01-01

    Long-term potentiation (LTP) and long-term depression (LTD) are two forms of synaptic plasticity that have been considered as the cellular substrate of memory formation. Although LTP has received considerable more attention, recent evidences indicate that LTD plays also important roles in the acquisition and storage of novel information in the brain. Pannexin 1 (Panx1) is a membrane protein that forms non-selective channels which have been shown to modulate the induction of hippocampal synaptic plasticity. Animals lacking Panx1 or blockade of Pannexin 1 channels precludes the induction of LTD and facilitates LTP. To evaluate if the absence of Panx1 also affects the acquisition of rapidly changing information we trained Panx1 knockout (KO) mice and wild type (WT) littermates in a visual and hidden version of the Morris water maze (MWM). We found that KO mice find the hidden platform similarly although slightly quicker than WT animals, nonetheless, when the hidden platform was located in the opposite quadrant (OQ) to the previous learned location, KO mice spent significantly more time in the previous quadrant than in the new location indicating that the absence of Panx1 affects the reversion of a previously acquired spatial memory. Consistently, we observed changes in the content of synaptic proteins critical to LTD, such as GluN2 subunits of N-methyl-D-aspartate receptors (NMDARs), which changed their contribution to synaptic plasticity in conditions of Panx1 ablation. Our findings give further support to the role of Panx1 channels on the modulation of synaptic plasticity induction, learning and memory processes. PMID:29692709

  19. Lack of Pannexin 1 Alters Synaptic GluN2 Subunit Composition and Spatial Reversal Learning in Mice

    Directory of Open Access Journals (Sweden)

    Ivana Gajardo

    2018-04-01

    Full Text Available Long-term potentiation (LTP and long-term depression (LTD are two forms of synaptic plasticity that have been considered as the cellular substrate of memory formation. Although LTP has received considerable more attention, recent evidences indicate that LTD plays also important roles in the acquisition and storage of novel information in the brain. Pannexin 1 (Panx1 is a membrane protein that forms non-selective channels which have been shown to modulate the induction of hippocampal synaptic plasticity. Animals lacking Panx1 or blockade of Pannexin 1 channels precludes the induction of LTD and facilitates LTP. To evaluate if the absence of Panx1 also affects the acquisition of rapidly changing information we trained Panx1 knockout (KO mice and wild type (WT littermates in a visual and hidden version of the Morris water maze (MWM. We found that KO mice find the hidden platform similarly although slightly quicker than WT animals, nonetheless, when the hidden platform was located in the opposite quadrant (OQ to the previous learned location, KO mice spent significantly more time in the previous quadrant than in the new location indicating that the absence of Panx1 affects the reversion of a previously acquired spatial memory. Consistently, we observed changes in the content of synaptic proteins critical to LTD, such as GluN2 subunits of N-methyl-D-aspartate receptors (NMDARs, which changed their contribution to synaptic plasticity in conditions of Panx1 ablation. Our findings give further support to the role of Panx1 channels on the modulation of synaptic plasticity induction, learning and memory processes.

  20. Mice lacking Brinp2 or Brinp3, or both, exhibit behaviours consistent with neurodevelopmental disorders

    Directory of Open Access Journals (Sweden)

    Susie Ruth Berkowicz

    2016-10-01

    Full Text Available Background: Brinps 1 – 3, and Astrotactins (Astn 1 and 2, are members of the Membrane Attack Complex / Perforin (MACPF superfamily that are predominantly expressed in the mammalian brain during development. Genetic variation at the human BRINP2/ASTN1 and BRINP1/ASTN2 loci has been implicated in neurodevelopmental disorders. We, and others, have previously shown that Brinp1-/- mice exhibit behaviour reminiscent of autism spectrum disorder (ASD and attention deficit hyperactivity disorder (ADHD.Method: We created Brinp2-/- mice and Brinp3-/- mice via the Cre-mediated LoxP system to investigate the effect of gene deletion on anatomy and behaviour. Additionally, Brinp2-/-Brinp3-/- double knock-out mice were generated by interbreeding Brinp2-/- and Brinp3-/- mice. Genomic validation was carried out for each knock-out line, followed by histological, weight and behavioural examination. Brinp1-/-Brinp2-/-Brinp3-/- triple knock-out mice were also generated by crossing Brinp2/3 double knock-out mice with previously generated Brinp1-/- mice, and examined by weight and histological analysis.Results: Brinp2-/- and Brinp3-/- mice differ in their behaviour: Brinp2-/- mice are hyperactive, whereas Brinp3-/- mice exhibit marked changes in anxiety-response on the elevated plus maze. Brinp3-/- mice also show evidence of altered sociability. Both Brinp2-/- and Brinp3-/- mice have normal short-term memory, olfactory responses, pre-pulse inhibition and motor learning. The double knock-out mice show behaviours of Brinp2-/- and Brinp3-/- mice, without evidence of new or exacerbated phenotypes. Conclusion: Brinp3 is important in moderation of anxiety, with potential relevance to anxiety disorders. Brinp2 dysfunction resulting in hyperactivity may be relevant to the association of ADHD with chromosome locus 1q25.2. Brinp2-/- and Brinp3-/- genes do not compensate in the mammalian brain and likely have distinct molecular or cell-type specific functions.

  1. The Biology of Autoimmune Response in the Scurfy Mice that Lack the CD4+Foxp3+ Regulatory T-Cells.

    Science.gov (United States)

    Ju, Shyr-Te; Sharma, Rahul; Gaskin, Felicia; Kung, John T; Fu, Shu Man

    2012-04-04

    Due to a mutation in the Foxp3 transcription factor, Scurfy mice lack regulatory T-cells that maintain self-tolerance of the immune system. They develop multi-organ inflammation (MOI) and die around four weeks old. The affected organs are skin, tail, lungs and liver. In humans, endocrine and gastrointestinal inflammation are also observed, hence the disease is termed IPEX (Immunodysregulation, Polyendocrinopathy, Enteropathy, X-linked) syndrome. The three week period of fatal MOI offers a useful autoimmune model in which the controls by genetics, T-cell subsets, cytokines, and effector mechanisms could be efficiently investigated. In this report, we will review published work, summarize our recent studies of Scurfy double mutants lacking specific autoimmune-related genes, discuss the cellular and cytokine controls by these genes on MOI, the organ-specificities of the MOI controlled by environments, and the effector mechanisms regulated by specific Th cytokines, including several newly identified control mechanisms for organ-specific autoimmune response.

  2. Differentially expressed genes in embryonic cardiac tissues of mice lacking Folr1 gene activity

    Directory of Open Access Journals (Sweden)

    Schwartz Robert J

    2007-11-01

    Full Text Available Abstract Background Heart anomalies are the most frequently observed among all human congenital defects. As with the situation for neural tube defects (NTDs, it has been demonstrated that women who use multivitamins containing folic acid peri-conceptionally have a reduced risk for delivering offspring with conotruncal heart defects 123. Cellular folate transport is mediated by a receptor or binding protein and by an anionic transporter protein system. Defective function of the Folr1 (also known as Folbp1; homologue of human FRα gene in mice results in inadequate transport, accumulation, or metabolism of folate during cardiovascular morphogenesis. Results We have observed cardiovascular abnormalities including outflow tract and aortic arch arterial defects in genetically compromised Folr1 knockout mice. In order to investigate the molecular mechanisms underlying the failure to complete development of outflow tract and aortic arch arteries in the Folr1 knockout mouse model, we examined tissue-specific gene expression difference between Folr1 nullizygous embryos and morphologically normal heterozygous embryos during early cardiac development (14-somite stage, heart tube looping (28-somite stage, and outflow track septation (38-somite stage. Microarray analysis was performed as a primary screening, followed by investigation using quantitative real-time PCR assays. Gene ontology analysis highlighted the following ontology groups: cell migration, cell motility and localization of cells, structural constituent of cytoskeleton, cell-cell adhesion, oxidoreductase, protein folding and mRNA processing. This study provided preliminary data and suggested potential candidate genes for further description and investigation. Conclusion The results suggested that Folr1 gene ablation and abnormal folate homeostasis altered gene expression in developing heart and conotruncal tissues. These changes affected normal cytoskeleton structures, cell migration and

  3. Variations of L- and D-amino acid levels in the brain of wild-type and mutant mice lacking D-amino acid oxidase activity.

    Science.gov (United States)

    Du, Siqi; Wang, Yadi; Weatherly, Choyce A; Holden, Kylie; Armstrong, Daniel W

    2018-05-01

    D-amino acids are now recognized to be widely present in organisms and play essential roles in biological processes. Some D-amino acids are metabolized by D-amino acid oxidase (DAO), while D-Asp and D-Glu are metabolized by D-aspartate oxidase (DDO). In this study, levels of 22 amino acids and the enantiomeric compositions of the 19 chiral proteogenic entities have been determined in the whole brain of wild-type ddY mice (ddY/DAO +/+ ), mutant mice lacking DAO activity (ddY/DAO -/- ), and the heterozygous mice (ddY/DAO +/- ) using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). No significant differences were observed for L-amino acid levels among the three strains except for L-Trp which was markedly elevated in the DAO +/- and DAO -/- mice. The question arises as to whether this is an unknown effect of DAO inactivity. The three highest levels of L-amino acids were L-Glu, L-Asp, and L-Gln in all the three strains. The lowest L-amino acid level was L-Cys in ddY/DAO +/- and ddY/DAO -/- mice, while L-Trp showed the lowest level in ddY/DAO +/+ mice. The highest concentration of D-amino acid was found to be D-Ser, which also had the highest % D value (~ 25%). D-Glu had the lowest % D value (~ 0.01%) in all the three strains. Significant differences of D-Leu, D-Ala, D-Ser, D-Arg, and D-Ile were observed in ddY/DAO +/- and ddY/DAO -/- mice compared to ddY/DAO +/+ mice. This work provides the most complete baseline analysis of L- and D-amino acids in the brains of ddY/DAO +/+ , ddY/DAO +/- , and ddY/DAO -/- mice yet reported. It also provides the most effective and efficient analytical approach for measuring these analytes in biological samples. This study provides fundamental information on the role of DAO in the brain and may be relevant for future development involving novel drugs for DAO regulation.

  4. Mice lacking ANGPTL8 (Betatrophin) manifest disrupted triglyceride metabolism without impaired glucose homeostasis.

    Science.gov (United States)

    Wang, Yan; Quagliarini, Fabiana; Gusarova, Viktoria; Gromada, Jesper; Valenzuela, David M; Cohen, Jonathan C; Hobbs, Helen H

    2013-10-01

    Angiopoietin-like protein (ANGPTL)8 (alternatively called TD26, RIFL, Lipasin, and Betatrophin) is a newly recognized ANGPTL family member that has been implicated in both triglyceride (TG) and glucose metabolism. Hepatic overexpression of ANGPTL8 causes hypertriglyceridemia and increased insulin secretion. Here we examined the effects of inactivating Angptl8 on TG and glucose metabolism in mice. Angptl8 knockout (Angptl8(-/-)) mice gained weight more slowly than wild-type littermates due to a selective reduction in adipose tissue accretion. Plasma levels of TGs of the Angptl8(-/-) mice were similar to wild-type animals in the fasted state but paradoxically decreased after refeeding. The lower TG levels were associated with both a reduction in very low density lipoprotein secretion and an increase in lipoprotein lipase (LPL) activity. Despite the increase in LPL activity, the uptake of very low density lipoprotein-TG is markedly reduced in adipose tissue but preserved in hearts of fed Angptl8(-/-) mice. Taken together, these data indicate that ANGPTL8 plays a key role in the metabolic transition between fasting and refeeding; it is required to direct fatty acids to adipose tissue for storage in the fed state. Finally, glucose and insulin tolerance testing revealed no alterations in glucose homeostasis in mice fed either a chow or high fat diet. Thus, although absence of ANGPTL8 profoundly disrupts TG metabolism, we found no evidence that it is required for maintenance of glucose homeostasis.

  5. An Examination of the Role of L-Glutamate and Inosine 5'-Monophosphate in Hedonic Taste-Guided Behavior by Mice Lacking the T1R1 + T1R3 Receptor.

    Science.gov (United States)

    Blonde, Ginger D; Spector, Alan C

    2017-06-01

    The heterodimeric T1R1 + T1R3 receptor is considered critical for normal signaling of L-glutamate and 5'-ribonucleotides in the oral cavity. However, some taste-guided responsiveness remains in mice lacking one subunit of the receptor, suggesting that other receptors are sufficient to support some behaviors. Here, mice lacking both receptor subunits (KO) and wild-type (WT, both n = 13) mice were tested in a battery of behavioral tests. Mice were trained and tested in gustometers with a concentration series of Maltrin-580, a maltodextrin, in a brief-access test (10-s trials) as a positive control. Similar tests followed with monosodium glutamate (MSG) with and without the ribonucleotide inosine 5'-monophosphate (IMP), but always in the presence of the epithelial sodium channel blocker amiloride (A). Brief-access tests were repeated following short-term (30-min) and long-term (48-h) exposures to MSG + A + IMP and were also conducted with sodium gluconate replacing MSG. Finally, progressive ratio tests were conducted with Maltrin-580 or MSG + A + IMP, to assess appetitive behavior while minimizing satiation. Overall, MSG generated little concentration-dependent responding in either food-restricted WT or KO mice, even in combination with IMP. However, KO mice licked less to the amino acid stimuli, a measure of consummatory behavior in the brief-access tests. In contrast, both groups initiated a similar number of trials and had a similar breakpoint in the progressive ratio task, both measures of appetitive (approach) behavior. Collectively, these results suggest that while the T1R1 + T1R3 receptor is necessary for consummatory responding to MSG (+IMP), other receptors are sufficient to maintain appetitive responding to this "umami" stimulus complex in food-restricted mice. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Environmental Enrichment Ameliorates Behavioral Impairments Modeling Schizophrenia in Mice Lacking Metabotropic Glutamate Receptor 5.

    Science.gov (United States)

    Burrows, Emma L; McOmish, Caitlin E; Buret, Laetitia S; Van den Buuse, Maarten; Hannan, Anthony J

    2015-07-01

    Schizophrenia arises from a complex interplay between genetic and environmental factors. Abnormalities in glutamatergic signaling have been proposed to underlie the emergence of symptoms, in light of various lines of evidence, including the psychotomimetic effects of NMDA receptor antagonists. Metabotropic glutamate receptor 5 (mGlu5) has also been implicated in the disorder, and has been shown to physically interact with NMDA receptors. To clarify the role of mGlu5-dependent behavioral expression by environmental factors, we assessed mGlu5 knockout (KO) mice after exposure to environmental enrichment (EE) or reared under standard conditions. The mGlu5 KO mice showed reduced prepulse inhibition (PPI), long-term memory deficits, and spontaneous locomotor hyperactivity, which were all attenuated by EE. Examining the cellular impact of genetic and environmental manipulation, we show that EE significantly increased pyramidal cell dendritic branching and BDNF protein levels in the hippocampus of wild-type mice; however, mGlu5 KO mice were resistant to these alterations, suggesting that mGlu5 is critical to these responses. A selective effect of EE on the behavioral response to the NMDA receptor antagonist MK-801 in mGlu5 KO mice was seen. MK-801-induced hyperlocomotion was further potentiated in enriched mGlu5 KO mice and treatment with MK-801 reinstated PPI disruption in EE mGlu5 KO mice only, a response that is absent under standard housing conditions. Together, these results demonstrate an important role for mGlu5 in environmental modulation of schizophrenia-related behavioral impairments. Furthermore, this role of the mGlu5 receptor is mediated by interaction with NMDA receptor function, which may inform development of novel therapeutics.

  7. Inhibition of Stat3 signaling ameliorates atrophy of the soleus muscles in mice lacking the vitamin D receptor.

    Science.gov (United States)

    Gopinath, Suchitra D

    2017-01-25

    Although skeletal muscle wasting has long been observed as a clinical outcome of impaired vitamin D signaling, precise molecular mechanisms that mediate the loss of muscle mass in the absence of vitamin D signaling are less clear. To determine the molecular consequences of vitamin D signaling, we analyzed the role of signal transducer and activator of transcription 3 (Stat3) signaling, a known contributor to various muscle wasting pathologies, in skeletal muscles. We isolated soleus (slow) and tibialis anterior (fast) muscles from mice lacking the vitamin D receptor (VDR -/- ) and used western blot analysis, quantitative RTPCR, and pharmacological intervention to analyze muscle atrophy in VDR -/- mice. We found that slow and fast subsets of muscles of the VDR -/- mice displayed elevated levels of phosphorylated Stat3 accompanied by an increase in Myostatin expression and signaling. Consequently, we observed reduced activity of mammalian target of rapamycin (mTOR) signaling components, ribosomal S6 kinase (p70S6K) and ribosomal S6 protein (rpS6), that regulate protein synthesis and cell size, respectively. Concomitantly, we observed an increase in atrophy regulators and a block in autophagic gene expression. An examination of the upstream regulation of Stat3 levels in VDR -/- muscles revealed an increase in IL-6 protein expression in the soleus, but not in the tibialis anterior muscles. To investigate the involvement of satellite cells (SCs) in atrophy in VDR -/- mice, we found that there was no significant deficit in SC numbers in VDR -/- muscles compared to the wild type. Unlike its expression within VDR -/- fibers, Myostatin levels in VDR -/- SCs from bulk muscles were similar to those of wild type. However, VDR -/- SCs induced to differentiate in culture displayed increased p-Stat3 signaling and Myostatin expression. Finally, VDR -/- mice injected with a Stat3 inhibitor displayed reduced Myostatin expression and function and restored active p70S6K and rpS6

  8. Epithelial cell stretching and luminal acidification lead to a retarded development of stria vascularis and deafness in mice lacking pendrin.

    Directory of Open Access Journals (Sweden)

    Hyoung-Mi Kim

    2011-03-01

    Full Text Available Loss-of-function mutations of SLC26A4/pendrin are among the most prevalent causes of deafness. Deafness and vestibular dysfunction in the corresponding mouse model, Slc26a4(-/-, are associated with an enlargement and acidification of the membranous labyrinth. Here we relate the onset of expression of the HCO(3 (- transporter pendrin to the luminal pH and to enlargement-associated epithelial cell stretching. We determined expression with immunocytochemistry, cell stretching by digital morphometry and pH with double-barreled ion-selective electrodes. Pendrin was first expressed in the endolymphatic sac at embryonic day (E 11.5, in the cochlear hook-region at E13.5, in the utricle and saccule at E14.5, in ampullae at E16.5, and in the upper turn of the cochlea at E17.5. Epithelial cell stretching in Slc26a4(-/- mice began at E14.5. pH changes occurred first in the cochlea at E15.5 and in the endolymphatic sac at E17.5. At postnatal day 2, stria vascularis, outer sulcus and Reissner's membrane epithelial cells, and utricular and saccular transitional cells were stretched, whereas sensory cells in the cochlea, utricle and saccule did not differ between Slc26a4(+/- and Slc26a4(-/- mice. Structural development of stria vascularis, including vascularization, was retarded in Slc26a4(-/- mice. In conclusion, the data demonstrate that the enlargement and stretching of non-sensory epithelial cells precedes luminal acidification in the cochlea and the endolymphatic sac. Stretching and luminal acidification may alter cell-to-cell communication and lead to the observed retarded development of stria vascularis, which may be an important step on the path to deafness in Slc26a4(-/- mice, and possibly in humans, lacking functional pendrin expression.

  9. Mice lacking cystathionine beta synthase have lung fibrosis and air space enlargement.

    Science.gov (United States)

    Hamelet, Julien; Maurin, Nicole; Fulchiron, Romain; Delabar, Jean-Maurice; Janel, Nathalie

    2007-10-01

    Cystathionine beta synthase (CBS) is a crucial regulator of plasma concentrations of homocysteine. Severe hyperhomocysteinemia due to CBS deficiency confers diverse clinical manifestations, notably pulmonary thrombotic disease. However, the association between hyperhomocysteinemia and chronic obstructive pulmonary disease is not well understood. To investigate the role of hyperhomocysteinemia in lung injury and pulmonary fibrosis, we analyzed the lung of CBS-deficient mice, a murine model of severe hyperhomocysteinemia. The degree of lung injury was assessed by histologic examination. Analysis of profibrogenic factors was performed by real-time quantitative reverse transcription-polymerase chain reaction. CBS-deficient mice develop fibrosis and air space enlargement in the lung, concomitant with an enhanced expression of heme oxygenase-1, pro(alpha)1 collagen type I, transforming growth factor-beta1 and alpha-smooth muscle actin. However, lung fibrosis was found in the absence of increased inflammatory cell infiltrates as determined by histology, without changes in gene expression of proinflammatory cytokines TNFalpha and interleukin 6. The increased expression of alpha-smooth muscle actin and transforming growth factor-beta1 emphasizes the role of myofibroblasts differentiation in case of lung fibrosis due to CBS deficiency in mice.

  10. Sympathetic activity induced by naloxone-precipitated morphine withdrawal is blocked in genetically engineered mice lacking functional CRF1 receptor

    International Nuclear Information System (INIS)

    García-Carmona, Juan-Antonio; Martínez-Laorden, Elena; Milanés, María-Victoria; Laorden, María-Luisa

    2015-01-01

    There is large body evidence indicating that stress can lead to cardiovascular disease. However, the exact brain areas and the mechanisms involved remain to be revealed. Here, we performed a series of experiments to characterize the role of CRF1 receptor (CRF1R) in the stress response induced by naloxone-precipitated morphine withdrawal. The experiments were performed in the hypothalamic paraventricular nucleus (PVN) ventrolateral medulla (VLM), brain regions involved in the regulation of cardiovascular activity, and in the right ventricle by using genetically engineered mice lacking functional CRF1R levels (KO). Mice were treated with increasing doses of morphine and withdrawal was precipitated by naloxone administration. Noradrenaline (NA) turnover, c-Fos, expression, PKA and TH phosphorylated at serine 40, was evaluated by high-performance liquid chromatography (HPLC), immunohistochemistry and immunoblotting. Morphine withdrawal induced an enhancement of NA turnover in PVN in parallel with an increase in TH neurons expressing c-Fos in VLM in wild-type mice. In addition we have demonstrated an increase in NA turnover, TH phosphorylated at serine 40 and PKA levels in heart. The main finding of the present study was that NA turnover, TH positive neurons that express c-Fos, TH phosphorylated at serine 40 and PKA expression observed during morphine withdrawal were significantly inhibited in CRF1R KO mice. Our results demonstrate that CRF/CRF1R activation may contribute to the adaptive changes induced by naloxone-precipitated withdrawal in the heart and in the brain areas which modulate the cardiac sympathetic function and suggest that CRF/CRF1R pathways could be contributing to cardiovascular disease associated to opioid addiction. - Highlights: • Naloxone-precipitated morphine withdrawal increases sympathetic activity in the PVN and heart. • Co-localization of TH phosphorylated at serine 40/c-Fos in the VLM after morphine withdrawal • Naloxone

  11. Sympathetic activity induced by naloxone-precipitated morphine withdrawal is blocked in genetically engineered mice lacking functional CRF1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    García-Carmona, Juan-Antonio; Martínez-Laorden, Elena; Milanés, María-Victoria; Laorden, María-Luisa

    2015-02-15

    There is large body evidence indicating that stress can lead to cardiovascular disease. However, the exact brain areas and the mechanisms involved remain to be revealed. Here, we performed a series of experiments to characterize the role of CRF1 receptor (CRF1R) in the stress response induced by naloxone-precipitated morphine withdrawal. The experiments were performed in the hypothalamic paraventricular nucleus (PVN) ventrolateral medulla (VLM), brain regions involved in the regulation of cardiovascular activity, and in the right ventricle by using genetically engineered mice lacking functional CRF1R levels (KO). Mice were treated with increasing doses of morphine and withdrawal was precipitated by naloxone administration. Noradrenaline (NA) turnover, c-Fos, expression, PKA and TH phosphorylated at serine 40, was evaluated by high-performance liquid chromatography (HPLC), immunohistochemistry and immunoblotting. Morphine withdrawal induced an enhancement of NA turnover in PVN in parallel with an increase in TH neurons expressing c-Fos in VLM in wild-type mice. In addition we have demonstrated an increase in NA turnover, TH phosphorylated at serine 40 and PKA levels in heart. The main finding of the present study was that NA turnover, TH positive neurons that express c-Fos, TH phosphorylated at serine 40 and PKA expression observed during morphine withdrawal were significantly inhibited in CRF1R KO mice. Our results demonstrate that CRF/CRF1R activation may contribute to the adaptive changes induced by naloxone-precipitated withdrawal in the heart and in the brain areas which modulate the cardiac sympathetic function and suggest that CRF/CRF1R pathways could be contributing to cardiovascular disease associated to opioid addiction. - Highlights: • Naloxone-precipitated morphine withdrawal increases sympathetic activity in the PVN and heart. • Co-localization of TH phosphorylated at serine 40/c-Fos in the VLM after morphine withdrawal • Naloxone

  12. Low bone mass and changes in the osteocyte network in mice lacking autophagy in the osteoblast lineage.

    Science.gov (United States)

    Piemontese, Marilina; Onal, Melda; Xiong, Jinhu; Han, Li; Thostenson, Jeff D; Almeida, Maria; O'Brien, Charles A

    2016-04-11

    Autophagy maintains cell function and homeostasis by recycling intracellular components. This process is also required for morphological changes associated with maturation of some cell types. Osteoblasts are bone forming cells some of which become embedded in bone and differentiate into osteocytes. This transformation includes development of long cellular projections and a reduction in endoplasmic reticulum and mitochondria. We examined the role of autophagy in osteoblasts by deleting Atg7 using an Osterix1-Cre transgene, which causes recombination in osteoblast progenitors and their descendants. Mice lacking Atg7 in the entire osteoblast lineage had low bone mass and fractures associated with reduced numbers of osteoclasts and osteoblasts. Suppression of autophagy also reduced the amount of osteocyte cellular projections and led to retention of endoplasmic reticulum and mitochondria in osteocytes. These results demonstrate that autophagy in osteoblasts contributes to skeletal homeostasis and to the morphological changes associated with osteocyte formation.

  13. Lack of skeletal muscle IL-6 influences hepatic glucose metabolism in mice during prolonged exercise

    DEFF Research Database (Denmark)

    Bertholdt, Lærke; Gudiksen, Anders; Schwartz, Camilla Lindgren

    2017-01-01

    The liver is essential in maintaining and regulating glucose homeostasis during prolonged exercise. IL-6 has been shown to be secreted from skeletal muscle during exercise and has been suggested to signal to the liver. Therefore, the aim of this study was to investigate the role of skeletal muscle...... IL-6 on hepatic glucose regulation and substrate choice during prolonged exercise. Skeletal muscle-specific IL-6 knockout (IL-6 MKO) mice (age, 12-14 wk) and littermate lox/lox (Control) mice were either rested (Rest) or completed a single bout of exercise for 10, 60, or 120 min, and the liver....... Furthermore, IL-6 MKO mice had higher hepatic pyruvate dehydrogenase (PDH)Ser232 and PDHSer300 phosphorylation than control mice at rest. In conclusion, hepatic gluconeogenic capacity in mice is increased during prolonged exercise independent of muscle IL-6. Furthermore, Skeletal muscle IL-6 influences...

  14. Comparative Assessment of Induced Immune Responses Following Intramuscular Immunization with Fusion and Cocktail of LeIF, LACK and TSA Genes Against Cutaneous Leishmaniasis in BALB/c Mice.

    Science.gov (United States)

    Maspi, Nahid; Ghaffarifar, Fatemeh; Sharifi, Zohreh; Dalimi, Abdolhossein; Dayer, Mohammad Saaid

    2018-02-01

    In the present study, we evaluated induced immune responses following DNA vaccine containing cocktail or fusion of LeIF, LACK and TSA genes or each gene alone. Mice were injected with 100 µg of each plasmid containing the gene of insert, plasmid DNA alone as the first control group or phosphate buffer saline as the second control group. Then, cellular and humoral responses, lesion size were measured for all groups. All vaccinated mice induced Th1 immune responses against Leishmania characterized by higher IFN-γ and IgG2a levels compared with control groups (p < 0.05). In addition, IFN-γ levels increased in groups immunized with fusion and cocktail vaccines in comparison with LACK (p < 0.001) and LeIF (p < 0.01) groups after challenge. In addition, fusion and cocktail groups produced higher IgG2a values than groups vaccinated with a gene alone (p < 0.05). Lesion progression delayed for all immunized groups compared with control groups from 5th week post-infection (p < 0.05). Mean lesion size decreased in immunized mice with fusion DNA than three groups vaccinated with one gene alone (p < 0.05). While, lesion size decreased significantly in cocktail recipient group than LeIF recipient group (p < 0.05). There was no difference in lesion size between fusion and cocktail groups. Overall, immunized mice with cocktail and fusion vaccines showed stronger Th1 response by production of higher IFN-γ and IgG2a and showed smaller mean lesion size. Therefore, use of multiple antigens can improve induced immune responses by DNA vaccination.

  15. Indirubin Derivative 7-Bromoindirubin-3-Oxime (7Bio Attenuates Aβ Oligomer-Induced Cognitive Impairments in Mice

    Directory of Open Access Journals (Sweden)

    Liping Chen

    2017-11-01

    Full Text Available Indirubins are natural occurring alkaloids extracted from indigo dye-containing plants. Indirubins could inhibit various kinases, and might be used to treat chronic myelocytic leukemia, cancer and neurodegenerative disorders. 7-bromoindirubin-3-oxime (7Bio, an indirubin derivative derived from indirubin-3-oxime, possesses inhibitory effects against cyclin-dependent kinase-5 (CDK5 and glycogen synthase kinase-3β (GSK3β, two pharmacological targets of Alzheimer's disease (AD. In this study, we have discovered that 2.3–23.3 μg/kg 7Bio effectively prevented β-amyloid (Aβ oligomer-induced impairments of spatial cognition and recognition without affecting bodyweight and motor functions in mice. Moreover, 7Bio potently inhibited Aβ oligomer-induced expression of interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α. Furthermore, 7Bio significantly prevented the decreased expression of synapsin-1 and PSD-95, biomarkers of pre-synaptic and post-synaptic proteins in Aβ oligomer-treated mice. The mean optical density (OD with hyper-phosphorylated tau (pTau, glial fibrillary acidic protein (GFAP and CD45 positive staining in the hippocampus of 7Bio-treated mice were significantly decreased compared to those of Aβ oligomer-treated mice. In addition, Western blotting analysis showed that 7Bio attenuated Aβ oligomer-decreased expression of pSer9-GSK3β. Those results suggested that 7Bio could potently inhibit Aβ oligomer-induced neuroinflammation, synaptic impairments, tau hyper-phosphorylation, and activation of astrocytes and microglia, which may contribute to the neuroprotective effects of 7Bio. Based on these findings, we expected that 7Bio might be developed as a novel anti-AD lead compound.

  16. Lack of tryptophan hydroxylase-1 in mice results in gait abnormalities.

    Science.gov (United States)

    Suidan, Georgette L; Duerschmied, Daniel; Dillon, Gregory M; Vanderhorst, Veronique; Hampton, Thomas G; Wong, Siu Ling; Voorhees, Jaymie R; Wagner, Denisa D

    2013-01-01

    The role of peripheral serotonin in nervous system development is poorly understood. Tryptophan hydroxylase-1 (TPH1) is expressed by non-neuronal cells including enterochromaffin cells of the gut, mast cells and the pineal gland and is the rate-limiting enzyme involved in the biosynthesis of peripheral serotonin. Serotonin released into circulation is taken up by platelets via the serotonin transporter and stored in dense granules. It has been previously reported that mouse embryos removed from Tph1-deficient mothers present abnormal nervous system morphology. The goal of this study was to assess whether Tph1-deficiency results in behavioral abnormalities. We did not find any differences between Tph1-deficient and wild-type mice in general motor behavior as tested by rotarod, grip-strength test, open field and beam walk. However, here we report that Tph1 (-/-) mice display altered gait dynamics and deficits in rearing behavior compared to wild-type (WT) suggesting that tryptophan hydroxylase-1 expression has an impact on the nervous system.

  17. Early signs of pathological cognitive aging in mice lacking high-affinity nicotinic receptors.

    Directory of Open Access Journals (Sweden)

    Eleni eKonsolaki

    2016-04-01

    Full Text Available In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. Α deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (β2-/-, which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioural signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviours, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm and extend the hypothesis that β2-/- animals exhibit age-related cognitive impairments, manifested in both spatial learning and recognition memory tasks. In addition, we reveal deficits in spontaneous behaviour and habituation processes earlier in life. To our knowledge, this is the first study to perform an extensive behavioural examination of an animal model of premature cognitive aging, and our results suggest that β2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioural changes to global dementia due to the combined effect of the neuropathology and aging.

  18. Mice Lacking EGR1 Have Impaired Clock Gene (BMAL1) Oscillation, Locomotor Activity, and Body Temperature.

    Science.gov (United States)

    Riedel, Casper Schwartz; Georg, Birgitte; Jørgensen, Henrik L; Hannibal, Jens; Fahrenkrug, Jan

    2018-01-01

    Early growth response transcription factor 1 (EGR1) is expressed in the suprachiasmatic nucleus (SCN) after light stimulation. We used EGR1-deficient mice to address the role of EGR1 in the clock function and light-induced resetting of the clock. The diurnal rhythms of expression of the clock genes BMAL1 and PER1 in the SCN were evaluated by semi-quantitative in situ hybridization. We found no difference in the expression of PER1 mRNA between wildtype and EGR1-deficient mice; however, the daily rhythm of BMAL1 mRNA was completely abolished in the EGR1-deficient mice. In addition, we evaluated the circadian running wheel activity, telemetric locomotor activity, and core body temperature of the mice. Loss of EGR1 neither altered light-induced phase shifts at subjective night nor affected negative masking. Overall, circadian light entrainment was found in EGR1-deficient mice but they displayed a reduced locomotor activity and an altered temperature regulation compared to wild type mice. When placed in running wheels, a subpopulation of EGR1-deficient mice displayed a more disrupted activity rhythm with no measurable endogenous period length (tau). In conclusion, the present study provides the first evidence that the circadian clock in the SCN is disturbed in mice deficient of EGR1.

  19. Dwarfism in mice lacking collagen-binding integrins alpha 2 beta 1 and alpha 11 beta 1 is caused by severely diminished IGF-1 levels

    OpenAIRE

    Blumbach, Katrin; Niehoff, Anja; Belgardt, Bengt F.; Ehlen, Harald W.A.; Schmitz, Markus; Hallinger, Ralf; Schulz, Jan-Niklas; Brüning, Jens C.; Krieg, Thomas; Schubert, Markus; Gullberg, Donald; Eckes, Beate

    2012-01-01

    Mice with a combined deficiency in the α2β1 and α11β1 integrins lack the major receptors for collagen I. These mutants are born with inconspicuous differences in size but develop dwarfism within the first 4 weeks of life. Dwarfism correlates with shorter, less mineralized and functionally weaker bones that do not result from growth plate abnormalities or osteoblast dysfunction. Besides skeletal dwarfism, internal organs are correspondingly smaller, indicating proportional dwarfism and suggest...

  20. Base excision repair deficient mice lacking the Aag alkyladenine DNA glycosylase.

    NARCIS (Netherlands)

    B.P. Engelward (Bevin); G. Weeda (Geert); M.D. Wyatt; J.L.M. Broekhof (Jose'); J. de Wit (Jan); I. Donker (Ingrid); J.M. Allan (James); B. Gold (Bert); J.H.J. Hoeijmakers (Jan); L.D. Samson (Leona)

    1997-01-01

    textabstract3-methyladenine (3MeA) DNA glycosylases remove 3MeAs from alkylated DNA to initiate the base excision repair pathway. Here we report the generation of mice deficient in the 3MeA DNA glycosylase encoded by the Aag (Mpg) gene. Alkyladenine DNA glycosylase turns out to be the major DNA

  1. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma.

    Science.gov (United States)

    Egawa, Junji; Schilling, Jan M; Cui, Weihua; Posadas, Edmund; Sawada, Atsushi; Alas, Basheer; Zemljic-Harpf, Alice E; Fannon-Pavlich, McKenzie J; Mandyam, Chitra D; Roth, David M; Patel, Hemal H; Patel, Piyush M; Head, Brian P

    2017-08-01

    Studies in vitro and in vivo demonstrate that membrane/lipid rafts and caveolin (Cav) organize progrowth receptors, and, when overexpressed specifically in neurons, Cav-1 augments neuronal signaling and growth and improves cognitive function in adult and aged mice; however, whether neuronal Cav-1 overexpression can preserve motor and cognitive function in the brain trauma setting is unknown. Here, we generated a neuron-targeted Cav-1-overexpressing transgenic (Tg) mouse [synapsin-driven Cav-1 (SynCav1 Tg)] and subjected it to a controlled cortical impact model of brain trauma and measured biochemical, anatomic, and behavioral changes. SynCav1 Tg mice exhibited increased hippocampal expression of Cav-1 and membrane/lipid raft localization of postsynaptic density protein 95, NMDA receptor, and tropomyosin receptor kinase B. When subjected to a controlled cortical impact, SynCav1 Tg mice demonstrated preserved hippocampus-dependent fear learning and memory, improved motor function recovery, and decreased brain lesion volume compared with wild-type controls. Neuron-targeted overexpression of Cav-1 in the adult brain prevents hippocampus-dependent learning and memory deficits, restores motor function after brain trauma, and decreases brain lesion size induced by trauma. Our findings demonstrate that neuron-targeted Cav-1 can be used as a novel therapeutic strategy to restore brain function and prevent trauma-associated maladaptive plasticity.-Egawa, J., Schilling, J. M., Cui, W., Posadas, E., Sawada, A., Alas, B., Zemljic-Harpf, A. E., Fannon-Pavlich, M. J., Mandyam, C. D., Roth, D. M., Patel, H. H., Patel, P. M., Head, B. P. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma. © FASEB.

  2. Antibody response against Betaferon® in immune tolerant mice: involvement of marginal zone B-cells and CD4+ T-cells and apparent lack of immunological memory.

    Science.gov (United States)

    Sauerborn, Melody; van Beers, Miranda M C; Jiskoot, Wim; Kijanka, Grzegorz M; Boon, Louis; Schellekens, Huub; Brinks, Vera

    2013-01-01

    The immunological processes underlying immunogenicity of recombinant human therapeutics are poorly understood. Using an immune tolerant mouse model we previously demonstrated that aggregates are a major trigger of the antidrug antibody (ADA) response against recombinant human interferon beta (rhIFNβ) products including Betaferon®, and that immunological memory seems to be lacking after a rechallenge with non-aggregated rhIFNβ. The apparent absence of immunological memory indicates a CD4+ T-cell independent (Tind) immune response underlying ADA formation against Betaferon®. This hypothesis was tested. Using the immune tolerant mouse model we first validated that rechallenge with highly aggregated rhIFNβ (Betaferon®) does not lead to a subsequent fast increase in ADA titers, suggesting a lack of immunological memory. Next we assessed whether Betaferon® could act as Tind antigen by inactivation of marginal zone (MZ) B-cells during treatment. MZ B-cells are major effector cells involved in a Tind immune response. In a following experiment we depleted the mice from CD4+ T-cells to test their involvement in the ADA response against Betaferon®. Inactivation of MZ B-cells at the start of Betaferon® treatment drastically lowered ADA levels, suggesting a Tind immune response. However, persistent depletion of CD4+ T-cells before and during Betaferon® treatment abolished the ADA response in almost all mice. The immune response against rhIFNβ in immune tolerant mice is neither a T-cell independent nor a classical T-cell dependent immune response. Further studies are needed to confirm absence of immunological memory (cells).

  3. Dengue envelope-based 'four-in-one' virus-like particles produced using Pichia pastoris induce enhancement-lacking, domain III-directed tetravalent neutralising antibodies in mice.

    Science.gov (United States)

    Rajpoot, Ravi Kant; Shukla, Rahul; Arora, Upasana; Swaminathan, Sathyamangalam; Khanna, Navin

    2018-06-05

    Dengue is a significant public health problem worldwide, caused by four antigenically distinct mosquito-borne dengue virus (DENV) serotypes. Antibodies to any given DENV serotype which can afford protection against that serotype tend to enhance infection by other DENV serotypes, by a phenomenon termed antibody-dependent enhancement (ADE). Antibodies to the viral pre-membrane (prM) protein have been implicated in ADE. We show that co-expression of the envelope protein of all four DENV serotypes, in the yeast Pichia pastoris, leads to their co-assembly, in the absence of prM, into tetravalent mosaic VLPs (T-mVLPs), which retain the serotype-specific antigenic integrity and immunogenicity of all four types of their monomeric precursors. Following a three-dose immunisation schedule, the T-mVLPs elicited EDIII-directed antibodies in mice which could neutralise all four DENV serotypes. Importantly, anti-T-mVLP antibodies did not augment sub-lethal DENV-2 infection of dengue-sensitive AG129 mice, based on multiple parameters. The 'four-in-one' tetravalent T-mVLPs possess multiple desirable features which may potentially contribute to safety (non-viral, prM-lacking and ADE potential-lacking), immunogenicity (induction of virus-neutralising antibodies), and low cost (single tetravalent immunogen produced using P. pastoris, an expression system known for its high productivity using simple inexpensive media). These results strongly warrant further exploration of this vaccine candidate.

  4. Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate.

    Science.gov (United States)

    Irie, Fumitoshi; Badie-Mahdavi, Hedieh; Yamaguchi, Yu

    2012-03-27

    Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism.

  5. Impairment of social behavior and communication in mice lacking the Uba6-dependent ubiquitin activation system.

    Science.gov (United States)

    Lee, Ji Yeon; Kwak, Minseok; Lee, Peter C W

    2015-03-15

    The Uba6-Use1 ubiquitin enzyme cascade is a poorly understood arm of the ubiquitin-proteasome system required for mouse development. Recently, we reported that Uba6 brain-specific knockout (termed NKO) mice display abnormal social behavior and neuronal development due to a decreased spine density and accumulation of Ube3a and Shank3. To better characterize a potential role for NKO mice in autism spectrum disorders (ASDs), we performed a comprehensive behavioral characterization of the social behavior and communication of NKO mice. Our behavioral results confirmed that NKO mice display social impairments, as indicated by fewer vocalizations and decreased social interaction. We conclude that UBA6 NKO mice represent a novel ASD mouse model of anti-social and less verbal behavioral symptoms. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Mice lacking the kf-1 gene exhibit increased anxiety- but not despair-like behavior

    Directory of Open Access Journals (Sweden)

    Atsushi Tsujimura

    2008-09-01

    Full Text Available KF-1 was originally identified as a protein encoded by human gene with increased expression in the cerebral cortex of a patient with Alzheimer’s disease. In mouse brain, kf-1 mRNA is detected predominantly in the hippocampus and cerebellum, and kf-1 gene expression is elevated also in the frontal cortex of rats after chronic antidepressant treatments. KF-1 mediates E2-dependent ubiquitination and may modulate cellular protein levels as an E3 ubiquitin ligase, though its target proteins are not yet identified. To elucidate the role of kf-1 in the central nervous system, we generated kf-1 knockout mice by gene targeting, using Cre-lox recombination. The resulting kf-1−/− mice were normal and healthy in appearance. Behavioral analyses revealed that kf-1−/− mice showed significantly increased anxiety-like behavior compared with kf-1+/+ littermates in the light/dark transition and elevated plus maze tests; however, no significant differences were observed in exploratory locomotion using the open field test or in behavioral despair using the forced swim and tail suspension tests. These observations suggest that KF-1 suppresses selectively anxiety under physiological conditions probably through modulating protein levels of its unknown target(s. Interestingly, kf-1−/− mice exhibited significantly increased prepulse inhibition, which is usually reduced in human schizophrenic patients. Thus, the kf-1−/− mice provide a novel animal model for elucidating molecular mechanisms of psychiatric diseases such as anxiety/depression, and may be useful for screening novel anxiolytic/antidepressant compounds.

  7. Spdef Null Mice Lack Conjunctival Goblet Cells and Provide a Model of Dry Eye

    OpenAIRE

    Marko, Christina K.; Menon, Balaraj B.; Chen, Gang; Whitsett, Jeffrey A.; Clevers, Hans; Gipson, Ilene K.

    2013-01-01

    Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef−/− mice, we determined that Spdef is required for conjunct...

  8. The transient outward current in mice lacking the potassium channel gene Kv1.4

    Science.gov (United States)

    London, Barry; Wang, Dao W; Hill, Joseph A; Bennett, Paul B

    1998-01-01

    The transient outward current (Ito) plays a prominent role in the repolarization phase of the cardiac action potential. Several K+ channel genes, including Kv1.4, are expressed in the heart, produce rapidly inactivating currents when heterologously expressed, and may be the molecular basis of Ito.We engineered mice homozygous for a targeted disruption of the K+ channel gene Kv1.4 and compared Ito in wild-type (Kv1.4+/+), heterozygous (Kv1.4+/-) and homozygous ‘knockout’ (Kv1.4−/−) mice. Kv1.4 RNA was truncated in Kv1.4−/− mice and protein expression was absent.Adult myocytes isolated from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice had large rapidly inactivating outward currents. The peak current densities at 60 mV (normalized by cellular capacitance, in pA pF−1; means ± s.e.m.) were 53.8 ± 5.3, 45.3 ± 2.2 and 44.4 ± 2.8 in cells from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice, respectively (P mice.The voltage dependence and time course of inactivation were not changed by targeted disruption of Kv1.4. The mean best-fitting V½ (membrane potential at 50 % inactivation) values for myocytes from Kv1.4 +/+, Kv1.4+/− and Kv1.4−/− mice were -53.5 ± 3.7, -51.1 ± 2.6 and -54.2 ± 2.4 mV, respectively. The slope factors (k) were -10.1 ± 1.4, -8.8 ± 1.4 and -9.5 ± 1.2 mV, respectively. The fast time constants for development of inactivation at -30 mV were 27.8 ± 2.2, 26.2 ± 5.1 and 19.6 ± 2.1 ms in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes, respectively. At +30 mV, they were 35.5 ± 2.6, 30.0 ± 2.1 and 28.7 ± 1.6 ms, respectively. The time constants for the rapid phase of recovery from inactivation at -80 mV were 32.5 ± 8.2, 23.3 ± 1.8 and 39.0 ± 3.7 ms, respectively.Nearly the entire inactivating component as well as more than 60 % of the steady-state outward current was eliminated by 1 mm 4-aminopyridine in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes.Western blot analysis of heart membrane extracts showed no significant

  9. The Lack of Cytotoxic Effect and Radioadaptive Response in Splenocytes of Mice Exposed to Low Level Internal β-Particle Irradiation through Tritiated Drinking Water in Vivo

    Directory of Open Access Journals (Sweden)

    Matthew Flegal

    2013-12-01

    Full Text Available Health effects of tritium, a β-emitter and a by-product of the nuclear industry, is a subject of significant controversy. This mouse in vivo study was undertaken to monitor biological effects of low level tritium exposure. Mice were exposed to tritiated drinking water (HTO at 10 KBq/L, 1 MBq/L and 20 MBq/L concentrations for one month. The treatment did not result in a significant increase of apoptosis in splenocytes. To examine if this low level tritium exposure alters radiosensitivity, the extracted splenocytes were challenged in vitro with 2 Gy γ-radiation, and apoptotic responses at 1 and 24 h were measured. No alterations in the radiosensitivity were detected in cells from mice exposed to tritium compared to sham-treated mice. In contrast, low dose γ-irradiation at 20 or 100 mGy, resulted in a significant increase in resistance to apoptotic cell death after 2 Gy irradiation; an indication of the radioadaptive response. Overall, our data suggest that low concentrations of tritium given to mice as HTO in drinking water do not exert cytotoxic effect in splenocytes, nor do they change cellular sensitivity to additional high dose γ-radiation. The latter may be considered as the lack of a radioadaptive response, typically observed after low dose γ-irradiation.

  10. Obesity resistance and multiple mechanisms of triglyceride synthesis in mice lacking Dgat.

    Science.gov (United States)

    Smith, S J; Cases, S; Jensen, D R; Chen, H C; Sande, E; Tow, B; Sanan, D A; Raber, J; Eckel, R H; Farese, R V

    2000-05-01

    Triglycerides (or triacylglycerols) represent the major form of stored energy in eukaryotes. Triglyceride synthesis has been assumed to occur primarily through acyl CoA:diacylglycerol transferase (Dgat), a microsomal enzyme that catalyses the final and only committed step in the glycerol phosphate pathway. Therefore, Dgat has been considered necessary for adipose tissue formation and essential for survival. Here we show that Dgat-deficient (Dgat-/-) mice are viable and can still synthesize triglycerides. Moreover, these mice are lean and resistant to diet-induced obesity. The obesity resistance involves increased energy expenditure and increased activity. Dgat deficiency also alters triglyceride metabolism in other tissues, including the mammary gland, where lactation is defective in Dgat-/- females. Our findings indicate that multiple mechanisms exist for triglyceride synthesis and suggest that the selective inhibition of Dgat-mediated triglyceride synthesis may be useful for treating obesity.

  11. Defective cancellous bone structure and abnormal response to PTH in cortical bone of mice lacking Cx43 cytoplasmic C-terminus domain

    Science.gov (United States)

    Pacheco-Costa, Rafael; Davis, Hannah M.; Sorenson, Chad; Hon, Mary C.; Hassan, Iraj; Reginato, Rejane D.; Allen, Matthew R.; Bellido, Teresita; Plotkin, Lilian I.

    2015-01-01

    Connexin43 (Cx43) forms gap junction channels and hemichannels that allow the communication among osteocytes, osteoblasts, and osteoclasts. Cx43 carboxy-terminal (CT) domain regulates channel opening and intracellular signaling by acting as a scaffold for structural and signaling proteins. To determine the role of Cx43 CT domain in bone, mice in which one allele of full length Cx43 was replaced by a mutant lacking the CT domain (Cx43ΔCT/fl) were studied. Cx43ΔCT/fl mice exhibit lower cancellous bone volume but higher cortical thickness than Cx43fl/fl controls, indicating that the CT domain is involved in normal cancellous bone gain but opposes cortical bone acquisition. Further, Cx43ΔCT is able to exert the functions of full length osteocytic Cx43 on cortical bone geometry and mechanical properties, demonstrating that domains other than the CT are responsible for Cx43 function in cortical bone. In addition, parathyroid hormone (PTH) failed to increase endocortical bone formation or energy to failure, a mechanical property that indicates resistance to fracture, in cortical bone in Cx43ΔCT mice with or without osteocytic full length Cx43. On the other hand, bone mass and bone formation markers were increased by the hormone in all mouse models, regardless of whether full length or Cx43ΔCT were or not expressed. We conclude that Cx43 CT domain is involved in proper bone acquisition; and that Cx43 expression in osteocytes is dispensable for some but not all PTH anabolic actions. PMID:26409319

  12. Occurrence of testicular microlithiasis in androgen insensitive hypogonadal mice

    Directory of Open Access Journals (Sweden)

    De Gendt Karl

    2009-08-01

    Full Text Available Abstract Background Testicular microliths are calcifications found within the seminiferous tubules. In humans, testicular microlithiasis (TM has an unknown etiology but may be significantly associated with testicular germ cell tumors. Factors inducing microlith development may also, therefore, act as susceptibility factors for malignant testicular conditions. Studies to identify the mechanisms of microlith development have been hampered by the lack of suitable animal models for TM. Methods This was an observational study of the testicular phenotype of different mouse models. The mouse models were: cryptorchid mice, mice lacking androgen receptors (ARs on the Sertoli cells (SCARKO, mice with a ubiquitous loss of androgen ARs (ARKO, hypogonadal (hpg mice which lack circulating gonadotrophins, and hpg mice crossed with SCARKO (hpg.SCARKO and ARKO (hpg.ARKO mice. Results Microscopic TM was seen in 94% of hpg.ARKO mice (n = 16 and the mean number of microliths per testis was 81 +/- 54. Occasional small microliths were seen in 36% (n = 11 of hpg testes (mean 2 +/- 0.5 per testis and 30% (n = 10 of hpg.SCARKO testes (mean 8 +/- 6 per testis. No microliths were seen in cryptorchid, ARKO or SCARKO mice. There was no significant effect of FSH or androgen on TM in hpg.ARKO mice. Conclusion We have identified a mouse model of TM and show that lack of endocrine stimulation is a cause of TM. Importantly, this model will provide a means with which to identify the mechanisms of TM development and the underlying changes in protein and gene expression.

  13. Mice lacking prostaglandin E receptor subtype 4 manifest disrupted lipid metabolism attributable to impaired triglyceride clearance.

    Science.gov (United States)

    Cai, Yin; Ying, Fan; Song, Erfei; Wang, Yu; Xu, Aimin; Vanhoutte, Paul M; Tang, Eva Hoi-Ching

    2015-12-01

    Upon high-fat feeding, prostaglandin E receptor subtype 4 (EP4)-knockout mice gain less body weight than their EP4(+/+) littermates. We investigated the cause of the lean phenotype. The mice showed a 68.8% reduction in weight gain with diminished fat mass that was not attributable to reduced food intake, fat malabsorption, or increased energy expenditure. Plasma triglycerides in the mice were elevated by 244.9%. The increase in plasma triglycerides was independent of changes in hepatic very low density lipoprotein (VLDL)-triglyceride production or intestinal chylomicron-triglyceride synthesis. However, VLDL-triglyceride clearance was drastically impaired in the EP4-knockout mice. The absence of EP4 in mice compromised the activation of lipoprotein lipase (LPL), the key enzyme responsible for trafficking of plasma triglycerides into peripheral tissues. Deficiency in EP4 reduced hepatic mRNA expression of the transcriptional factor cAMP response element binding protein H (by 36.8%) and LPL activators, including apolipoprotein (Apo)a5 (by 40.2%) and Apoc2 (by 61.3%). In summary, the lean phenotype of EP4-deficient mice resulted from reduction in adipose tissue and accretion of other peripheral organs caused by impaired triglyceride clearance. The findings identify a new metabolic dimension in the physiologic role played by endogenous EP4. © FASEB.

  14. Control of blood pressure, appetite, and glucose by leptin in mice lacking leptin receptors in proopiomelanocortin neurons.

    Science.gov (United States)

    do Carmo, Jussara M; da Silva, Alexandre A; Cai, Zhengwei; Lin, Shuying; Dubinion, John H; Hall, John E

    2011-05-01

    Although the central nervous system melanocortin system is an important regulator of energy balance, the role of proopiomelanocortin (POMC) neurons in mediating the chronic effects of leptin on appetite, blood pressure, and glucose regulation is unknown. Using Cre/loxP technology we tested whether leptin receptor deletion in POMC neurons (LepR(flox/flox)/POMC-Cre mice) attenuates the chronic effects of leptin to increase mean arterial pressure (MAP), enhance glucose use and oxygen consumption, and reduce appetite. LepR(flox/flox)/POMC-Cre, wild-type, LepR(flox/flox), and POMC-Cre mice were instrumented for MAP and heart rate measurement by telemetry and venous catheters for infusions. LepR(flox/flox)/POMC-Cre mice were heavier, hyperglycemic, hyperinsulinemic, and hyperleptinemic compared with wild-type, LepR(flox/flox), and POMC-Cre mice. Despite exhibiting features of metabolic syndrome, LepR(flox/flox)/POMC-Cre mice had normal MAP and heart rate compared with LepR(flox/flox) but lower MAP and heart rate compared with wild-type mice. After a 5-day control period, leptin was infused (2 μg/kg per minute, IV) for 7 days. In control mice, leptin increased MAP by ≈5 mm Hg despite decreasing food intake by ≈35%. In contrast, leptin infusion in LepR(flox/flox)/POMC-Cre mice reduced MAP by ≈3 mm Hg and food intake by ≈28%. Leptin significantly decreased insulin and glucose levels in control mice but not in LepR(flox/flox)/POMC-Cre mice. Leptin increased oxygen consumption in LepR(flox/flox)/POMC-Cre and wild-type mice. Activation of POMC neurons is necessary for the chronic effects of leptin to raise MAP and reduce insulin and glucose levels, whereas leptin receptors in other areas of the brain other than POMC neurons appear to play a key role in mediating the chronic effects of leptin on appetite and oxygen consumption.

  15. Impaired neuronal maturation of hippocampal neural progenitor cells in mice lacking CRAF.

    Science.gov (United States)

    Pfeiffer, Verena; Götz, Rudolf; Camarero, Guadelupe; Heinsen, Helmut; Blum, Robert; Rapp, Ulf Rüdiger

    2018-01-01

    RAF kinases are major constituents of the mitogen activated signaling pathway, regulating cell proliferation, differentiation and cell survival of many cell types, including neurons. In mammals, the family of RAF proteins consists of three members, ARAF, BRAF, and CRAF. Ablation of CRAF kinase in inbred mouse strains causes major developmental defects during fetal growth and embryonic or perinatal lethality. Heterozygous germline mutations in CRAF result in Noonan syndrome, which is characterized by neurocognitive impairment that may involve hippocampal physiology. The role of CRAF signaling during hippocampal development and generation of new postnatal hippocampal granule neurons has not been examined and may provide novel insight into the cause of hippocampal dysfunction in Noonan syndrome. In this study, by crossing CRAF-deficiency to CD-1 outbred mice, a CRAF mouse model was established which enabled us to investigate the interplay of neural progenitor proliferation and postmitotic differentiation during adult neurogenesis in the hippocampus. Albeit the general morphology of the hippocampus was unchanged, CRAF-deficient mice displayed smaller granule cell layer (GCL) volume at postnatal day 30 (P30). In CRAF-deficient mice a substantial number of abnormal, chromophilic, fast dividing cells were found in the subgranular zone (SGZ) and hilus of the dentate gyrus (DG), indicating that CRAF signaling contributes to hippocampal neural progenitor proliferation. CRAF-deficient neural progenitor cells showed an increased cell death rate and reduced neuronal maturation. These results indicate that CRAF function affects postmitotic neural cell differentiation and points to a critical role of CRAF-dependent growth factor signaling pathway in the postmitotic development of adult-born neurons.

  16. Inositol- and folate-resistant neural tube defects in mice lacking the epithelial-specific factor Grhl-3.

    Science.gov (United States)

    Ting, Stephen B; Wilanowski, Tomasz; Auden, Alana; Hall, Mark; Voss, Anne K; Thomas, Tim; Parekh, Vishwas; Cunningham, John M; Jane, Stephen M

    2003-12-01

    The neural tube defects (NTDs) spina bifida and anencephaly are widely prevalent severe birth defects. The mouse mutant curly tail (ct/ct) has served as a model of NTDs for 50 years, even though the responsible genetic defect remained unrecognized. Here we show by gene targeting, mapping and genetic complementation studies that a mouse homolog of the Drosophila grainyhead (grh) gene, grainyhead-like-3 (Grhl3), is a compelling candidate for the gene underlying the curly tail phenotype. The NTDs in Grhl3-null mice are more severe than those in the curly tail strain, as the Grhl3 alleles in ct/ct mice are hypomorphic. Spina bifida in ct/ct mice is folate resistant, but its incidence can be markedly reduced by maternal inositol supplementation periconceptually. The NTDs in Grhl3-/- embryos are also folate resistant, but unlike those in ct/ct mice, they are resistant to inositol. These findings suggest that residual Grhl3 expression in ct/ct mice may be required for inositol rescue of folate-resistant NTDs.

  17. Premature Aging Phenotype in Mice Lacking High-Affinity Nicotinic Receptors: Region-Specific Changes in Layer V Pyramidal Cell Morphology.

    Science.gov (United States)

    Konsolaki, Eleni; Skaliora, Irini

    2015-08-01

    The mechanisms by which aging leads to alterations in brain structure and cognitive deficits are unclear. Α deficient cholinergic system has been implicated as one of the main factors that could confer a heightened vulnerability to the aging process, and mice lacking high-affinity nicotinic receptors (β2(-/-)) have been proposed as an animal model of accelerated cognitive aging. To date, however, age-related changes in neuronal microanatomy have not been studied in these mice. In the present study, we examine the neuronal structure of yellow fluorescent protein (YFP(+)) layer V neurons in 2 cytoarchitectonically distinct cortical regions in wild-type (WT) and β2(-/-) animals. We find that (1) substantial morphological differences exist between YFP(+) cells of the anterior cingulate cortex (ACC) and primary visual cortex (V1), in both genotypes; (2) in WT animals, ACC cells are more susceptible to aging compared with cells in V1; and (3) β2 deletion is associated with a regionally and temporally specific increase in vulnerability to aging. ACC cells exhibit a prematurely aged phenotype already at 4-6 months, whereas V1 cells are spared in adulthood but strongly affected in old animals. Collectively, our data reveal region-specific synergistic effects of aging and genotype and suggest distinct vulnerabilities in V1 and ACC neurons. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Normal viability and altered pharmacokinetics in mice lacking mdr1-type (drug-transporting) P-glycoproteins

    NARCIS (Netherlands)

    Schinkel, A. H.; Mayer, U.; Wagenaar, E.; Mol, C. A.; van Deemter, L.; Smit, J. J.; van der Valk, M. A.; Voordouw, A. C.; Spits, H.; van Tellingen, O.; Zijlmans, J. M.; Fibbe, W. E.; Borst, P.

    1997-01-01

    The mdr1-type P-glycoproteins (P-gps) confer multidrug resistance to cancer cells by active extrusion of a wide range of drugs from the cell. To study their physiological roles, we have generated mice genetically deficient in the mdr1b gene [mdr1b (-/-) mice] and in both the mdr1a and mdr1b genes

  19. Lack of Neuronal IFN-β-IFNAR Causes Lewy Body- and Parkinson's Disease-like Dementia

    DEFF Research Database (Denmark)

    Ejlerskov, Patrick; Hultberg, Jeanette Göransdotter; Wang, JunYang

    2015-01-01

    -causing mutant proteins. Mice lacking Ifnb function exhibited motor and cognitive learning impairments with accompanying α-synuclein-containing Lewy bodies in the brain, as well as a reduction in dopaminergic neurons and defective dopamine signaling in the nigrostriatal region. Lack of IFN-β signaling caused...

  20. Dietary antioxidants prevent age-related retinal pigment epithelium actin damage and blindness in mice lacking αvβ5 integrin

    Science.gov (United States)

    Yu, Chia-Chia; Nandrot, Emeline F.; Dun, Ying; Finnemann, Silvia C.

    2011-01-01

    In the aging human eye, oxidative damage and accumulation of pro-oxidant lysosomal lipofuscin cause functional decline of the retinal pigment epithelium (RPE), which contributes to age-related macular degeneration. In mice with an RPE-specific phagocytosis defect due to lack of αvβ5 integrin receptors, RPE accumulation of lipofuscin suggests that the age-related blindness we previously described in this model may also result from oxidative stress. Cellular and molecular targets of oxidative stress in the eye remain poorly understood. Here we identify actin among 4-hydroxynonenal (HNE) adducts formed specifically in β5−/− RPE but not neural retina with age. HNE modification directly correlated with loss of resistance of actin to detergent extraction, suggesting cytoskeletal damage in aging RPE. Dietary enrichment with natural antioxidants grapes or marigold extract containing macular pigments lutein/zeaxanthin was sufficient to prevent HNE-adduct formation, actin solubility, lipofuscin accumulation, and age-related cone and rod photoreceptor dysfunction in β5−/− mice. Acute generation of HNE-adducts directly destabilized actin but not tubulin cytoskeletal elements of RPE cells. These findings identify destabilization of the actin cytoskeleton as a consequence of physiological, sublethal oxidative burden of RPE cells in vivo that is associated with age-related blindness and that can be prevented by consuming an antioxidant-rich diet. PMID:22178979

  1. Conditioned place preference and locomotor activity in response to methylphenidate, amphetamine and cocaine in mice lacking dopamine D4 receptors

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, P.K.; Thanos, P.K.; Bermeo, C.; Rubinstein, M.; Suchland, K.L.; Wang, G.-J.; Grandy, D.K.; Volkow, N.D.

    2010-05-01

    Methylphenidate (MP) and amphetamine (AMPH) are the most frequently prescribed medications for the treatment of attention-deficit/hyperactivity disorder (ADHD). Both drugs are believed to derive their therapeutic benefit by virtue of their dopamine (DA)-enhancing effects, yet an explanation for the observation that some patients with ADHD respond well to one medication but not to the other remains elusive. The dopaminergic effects of MP and AMPH are also thought to underlie their reinforcing properties and ultimately their abuse. Polymorphisms in the human gene that codes for the DA D4 receptor (D4R) have been repeatedly associated with ADHD and may correlate with the therapeutic as well as the reinforcing effects of responses to these psychostimulant medications. Conditioned place preference (CPP) for MP, AMPH and cocaine were evaluated in wild-type (WT) mice and their genetically engineered littermates, congenic on the C57Bl/6J background, that completely lack D4Rs (knockout or KO). In addition, the locomotor activity in these mice during the conditioning phase of CPP was tested in the CPP chambers. D4 receptor KO and WT mice showed CPP and increased locomotor activity in response to each of the three psychostimulants tested. D4R differentially modulates the CPP responses to MP, AMPH and cocaine. While the D4R genotype affected CPP responses to MP (high dose only) and AMPH (low dose only) it had no effects on cocaine. Inasmuch as CPP is considered an indicator of sensitivity to reinforcing responses to drugs these data suggest a significant but limited role of D4Rs in modulating conditioning responses to MP and AMPH. In the locomotor test, D4 receptor KO mice displayed attenuated increases in AMPH-induced locomotor activity whereas responses to cocaine and MP did not differ. These results suggest distinct mechanisms for D4 receptor modulation of the reinforcing (perhaps via attenuating dopaminergic signalling) and locomotor properties of these stimulant drugs

  2. Developmental alterations in motor coordination and medium spiny neuron markers in mice lacking pgc-1α.

    Directory of Open Access Journals (Sweden)

    Elizabeth K Lucas

    Full Text Available Accumulating evidence implicates the transcriptional coactivator peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α in the pathophysiology of Huntington Disease (HD. Adult PGC-1α (-/- mice exhibit striatal neurodegeneration, and reductions in the expression of PGC-1α have been observed in striatum and muscle of HD patients as well as in animal models of the disease. However, it is unknown whether decreased expression of PGC-1α alone is sufficient to lead to the motor phenotype and striatal pathology characteristic of HD. For the first time, we show that young PGC-1α (-/- mice exhibit severe rotarod deficits, decreased rearing behavior, and increased occurrence of tremor in addition to the previously described hindlimb clasping. Motor impairment and striatal vacuolation are apparent in PGC-1α (-/- mice by four weeks of age and do not improve or decline by twelve weeks of age. The behavioral and pathological phenotype of PGC-1α (-/- mice can be completely recapitulated by conditional nervous system deletion of PGC-1α, indicating that peripheral effects are not responsible for the observed abnormalities. Evaluation of the transcriptional profile of PGC-1α (-/- striatal neuron populations and comparison to striatal neuron profiles of R6/2 HD mice revealed that PGC-1α deficiency alone is not sufficient to cause the transcriptional changes observed in this HD mouse model. In contrast to R6/2 HD mice, PGC-1α (-/- mice show increases in the expression of medium spiny neuron (MSN markers with age, suggesting that the observed behavioral and structural abnormalities are not primarily due to MSN loss, the defining pathological feature of HD. These results indicate that PGC-1α is required for the proper development of motor circuitry and transcriptional homeostasis in MSNs and that developmental disruption of PGC-1α leads to long-term alterations in motor functioning.

  3. Mice Lacking Pannexin 1 Release ATP and Respond Normally to All Taste Qualities.

    Science.gov (United States)

    Vandenbeuch, Aurelie; Anderson, Catherine B; Kinnamon, Sue C

    2015-09-01

    Adenosine triphosphate (ATP) is required for the transmission of all taste qualities from taste cells to afferent nerve fibers. ATP is released from Type II taste cells by a nonvesicular mechanism and activates purinergic receptors containing P2X2 and P2X3 on nerve fibers. Several ATP release channels are expressed in taste cells including CALHM1, Pannexin 1, Connexin 30, and Connexin 43, but whether all are involved in ATP release is not clear. We have used a global Pannexin 1 knock out (Panx1 KO) mouse in a series of in vitro and in vivo experiments. Our results confirm that Panx1 channels are absent in taste buds of the knockout mice and that other known ATP release channels are not upregulated. Using a luciferin/luciferase assay, we show that circumvallate taste buds from Panx1 KO mice normally release ATP upon taste stimulation compared with wild type (WT) mice. Gustatory nerve recordings in response to various tastants applied to the tongue and brief-access behavioral testing with SC45647 also show no difference between Panx1 KO and WT. These results confirm that Panx1 is not required for the taste evoked release of ATP or for neural and behavioral responses to taste stimuli. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Lack of genotoxic potential of pesticides, spinosad, imidacloprid and neem oil in mice (Mus musculus).

    Science.gov (United States)

    Saxena, Ankita; Kesari, V P

    2016-03-01

    Pesticides, spinosad, imidacloprid and neem oil are widely used both in residential and agricultural environments because of its broad spectrum insecticidal activity and effectiveness. The present study was undertaken to estimate genotoxicity of formulations of some pesticides in mice. Three pesticides of diverse group studied were spinosad (45% w/v), imidacloprid (17.8%, w/v) and neem oil. Animals were exposed 37, 4.5 and 50 mg kg⁻¹ b.wt. for spinosad, imidacloprid and neem oil, respectively, through oral gavage for 5 consecutive days. A vehicle control group and one positive control (cyclophosphamide; 20 mg kg⁻¹ b. wt.) were also selected. The results showed that cyclophosphamide produced 1.12% micronuclei in mice, as against 0.18 in vehicle control, 0.30 in spinosad, 0.28 in imidacloprid and 0.22% in neem oil, respectively. The gross percentage of chromosomal aberration in mice were 28.5% in cyclophosphamide against 6.5% in vehicle control, 8.0% in spinosad, 9.5% in imidacloprid and 7.0% in neem oil, respectively. The overall findings of the present study revealed that all the three pesticide formulations, imidacloprid, spinosad and neem oil at tested dose did not show any genotoxic effect in mice.

  5. Mice lacking collapsin response mediator protein 1 manifest hyperactivity, impaired learning and memory, and impaired prepulse inhibition

    Directory of Open Access Journals (Sweden)

    Naoya eYamashita

    2013-12-01

    Full Text Available Collapsin response mediator protein 1 (CRMP1 is one of the CRMP family members that are involved in various aspects of neuronal development such as axonal guidance and neuronal migration. Here we provide evidence that crmp1-/- mice exhibited behavioral abnormalities related to schizophrenia. The crmp1-/- mice exhibited hyperactivity and/or impaired emotional behavioral phenotype. These mice also exhibited impaired context-dependent memory and long-term memory retention. Furthermore, crmp1-/- mice exhibited decreased prepulse inhibition, and this phenotype was rescued by administration of chlorpromazine, a typical antipsychotic drug. In addition, in vivo microdialysis revealed that the methamphetamine-induced release of dopamine in prefrontal cortex was exaggerated in crmp1-/- mice, suggesting that enhanced mesocortical dopaminergic transmission contributes to their hyperactivity phenotype. These observations suggest that impairment of CRMP1 function may be involved in the pathogenesis of schizophrenia. We propose that crmp1-/- mouse may model endophenotypes present in this neuropsychiatric disorder.

  6. Mice deficient in 11beta-hydroxysteroid dehydrogenase type 1 lack bone marrow adipocytes, but maintain normal bone formation

    DEFF Research Database (Denmark)

    Justesen, Jeannette; Mosekilde, Lis; Holmes, Megan

    2004-01-01

    Glucocorticoids (GCs) exert potent, but poorly characterized, effects on the skeleton. The cellular activity of GCs is regulated at a prereceptor level by 11beta-hydroxysteroid dehydrogenases (11betaHSDs). The type 1 isoform, which predominates in bone, functions as a reductase in intact cells...... and regenerates active cortisol (corticosterone) from circulating inert 11-keto forms. The aim of the present study was to investigate the role of this intracrine activation of GCs on normal bone physiology in vivo using mice deficient in 11betaHSD1 (HSD1(-/-)). The HSD1(-/-) mice exhibited no significant changes...... in cortical or trabecular bone mass compared with wild-type (Wt) mice. Aged HSD1(-/-) mice showed age-related bone loss similar to that observed in Wt mice. Histomorphometric analysis showed similar bone formation and bone resorption parameters in HSD1(-/-) and Wt mice. However, examination of bone marrow...

  7. Central diabetes insipidus associated with impaired renal aquaporin-1 expression in mice lacking liver X receptor β.

    Science.gov (United States)

    Gabbi, Chiara; Kong, Xiaomu; Suzuki, Hitoshi; Kim, Hyun-Jin; Gao, Min; Jia, Xiao; Ohnishi, Hideo; Ueta, Yoichi; Warner, Margaret; Guan, Youfei; Gustafsson, Jan-Åke

    2012-02-21

    The present study demonstrates a key role for the oxysterol receptor liver X receptor β (LXRβ) in the etiology of diabetes insipidus (DI). Given free access to water, LXRβ(-/-) but not LXRα(-/-) mice exhibited polyuria (abnormal daily excretion of highly diluted urine) and polydipsia (increased water intake), both features of diabetes insipidus. LXRβ(-/-) mice responded to 24-h dehydration with a decreased urine volume and increased urine osmolality. To determine whether the DI was of central or nephrogenic origin, we examined the responsiveness of the kidney to arginine vasopressin (AVP). An i.p. injection of AVP to LXRβ(-/-) mice revealed a partial kidney response: There was no effect on urine volume, but there was a significant increase of urine osmolality, suggesting that DI may be caused by a defect in central production of AVP. In the brain of WT mice LXRβ was expressed in the nuclei of magnocellular neurons in the supraoptic and paraventricular nuclei of the hypothalamus. In LXRβ(-/-) mice the expression of AVP was markedly decreased in the magnocellular neurons as well as in urine collected over a 24-h period. The persistent high urine volume after AVP administration was traced to a reduction in aquaporin-1 expression in the kidney of LXRβ(-/-) mice. The LXR agonist (GW3965) in WT mice elicited an increase in urine osmolality, suggesting that LXRβ is a key receptor in controlling water balance with targets in both the brain and kidney, and it could be a therapeutic target in disorders of water balance.

  8. Tauopathy induced by low level expression of a human brain-derived tau fragment in mice is rescued by phenylbutyrate.

    Science.gov (United States)

    Bondulich, Marie K; Guo, Tong; Meehan, Christopher; Manion, John; Rodriguez Martin, Teresa; Mitchell, Jacqueline C; Hortobagyi, Tibor; Yankova, Natalia; Stygelbout, Virginie; Brion, Jean-Pierre; Noble, Wendy; Hanger, Diane P

    2016-08-01

    Human neurodegenerative tauopathies exhibit pathological tau aggregates in the brain along with diverse clinical features including cognitive and motor dysfunction. Post-translational modifications including phosphorylation, ubiquitination and truncation, are characteristic features of tau present in the brain in human tauopathy. We have previously reported an N-terminally truncated form of tau in human brain that is associated with the development of tauopathy and is highly phosphorylated. We have generated a new mouse model of tauopathy in which this human brain-derived, 35 kDa tau fragment (Tau35) is expressed in the absence of any mutation and under the control of the human tau promoter. Most existing mouse models of tauopathy overexpress mutant tau at levels that do not occur in human neurodegenerative disease, whereas Tau35 transgene expression is equivalent to less than 10% of that of endogenous mouse tau. Tau35 mice recapitulate key features of human tauopathies, including aggregated and abnormally phosphorylated tau, progressive cognitive and motor deficits, autophagic/lysosomal dysfunction, loss of synaptic protein, and reduced life-span. Importantly, we found that sodium 4-phenylbutyrate (Buphenyl®), a drug used to treat urea cycle disorders and currently in clinical trials for a range of neurodegenerative diseases, reverses the observed abnormalities in tau and autophagy, behavioural deficits, and loss of synapsin 1 in Tau35 mice. Our results show for the first time that, unlike other tau transgenic mouse models, minimal expression of a human disease-associated tau fragment in Tau35 mice causes a profound and progressive tauopathy and cognitive changes, which are rescued by pharmacological intervention using a clinically approved drug. These novel Tau35 mice therefore represent a highly disease-relevant animal model in which to investigate molecular mechanisms and to develop novel treatments for human tauopathies. © The Author (2016). Published by

  9. Tauopathy induced by low level expression of a human brain-derived tau fragment in mice is rescued by phenylbutyrate

    Science.gov (United States)

    Bondulich, Marie K.; Guo, Tong; Meehan, Christopher; Manion, John; Rodriguez Martin, Teresa; Mitchell, Jacqueline C.; Hortobagyi, Tibor; Yankova, Natalia; Stygelbout, Virginie; Brion, Jean-Pierre; Noble, Wendy

    2016-01-01

    Abstract Human neurodegenerative tauopathies exhibit pathological tau aggregates in the brain along with diverse clinical features including cognitive and motor dysfunction. Post-translational modifications including phosphorylation, ubiquitination and truncation, are characteristic features of tau present in the brain in human tauopathy. We have previously reported an N-terminally truncated form of tau in human brain that is associated with the development of tauopathy and is highly phosphorylated. We have generated a new mouse model of tauopathy in which this human brain-derived, 35 kDa tau fragment (Tau35) is expressed in the absence of any mutation and under the control of the human tau promoter. Most existing mouse models of tauopathy overexpress mutant tau at levels that do not occur in human neurodegenerative disease, whereas Tau35 transgene expression is equivalent to less than 10% of that of endogenous mouse tau. Tau35 mice recapitulate key features of human tauopathies, including aggregated and abnormally phosphorylated tau, progressive cognitive and motor deficits, autophagic/lysosomal dysfunction, loss of synaptic protein, and reduced life-span. Importantly, we found that sodium 4-phenylbutyrate (Buphenyl®), a drug used to treat urea cycle disorders and currently in clinical trials for a range of neurodegenerative diseases, reverses the observed abnormalities in tau and autophagy, behavioural deficits, and loss of synapsin 1 in Tau35 mice. Our results show for the first time that, unlike other tau transgenic mouse models, minimal expression of a human disease-associated tau fragment in Tau35 mice causes a profound and progressive tauopathy and cognitive changes, which are rescued by pharmacological intervention using a clinically approved drug. These novel Tau35 mice therefore represent a highly disease-relevant animal model in which to investigate molecular mechanisms and to develop novel treatments for human tauopathies. PMID:27297240

  10. Severe Extracellular Matrix Abnormalities and Chondrodysplasia in Mice Lacking Collagen Prolyl 4-Hydroxylase Isoenzyme II in Combination with a Reduced Amount of Isoenzyme I.

    Science.gov (United States)

    Aro, Ellinoora; Salo, Antti M; Khatri, Richa; Finnilä, Mikko; Miinalainen, Ilkka; Sormunen, Raija; Pakkanen, Outi; Holster, Tiina; Soininen, Raija; Prein, Carina; Clausen-Schaumann, Hauke; Aszódi, Attila; Tuukkanen, Juha; Kivirikko, Kari I; Schipani, Ernestina; Myllyharju, Johanna

    2015-07-03

    Collagen prolyl 4-hydroxylases (C-P4H-I, C-P4H-II, and C-P4H-III) catalyze formation of 4-hydroxyproline residues required to form triple-helical collagen molecules. Vertebrate C-P4Hs are α2β2 tetramers differing in their catalytic α subunits. C-P4H-I is the major isoenzyme in most cells, and inactivation of its catalytic subunit (P4ha1(-/-)) leads to embryonic lethality in mouse, whereas P4ha1(+/-) mice have no abnormalities. To study the role of C-P4H-II, which predominates in chondrocytes, we generated P4ha2(-/-) mice. Surprisingly, they had no apparent phenotypic abnormalities. To assess possible functional complementarity, we established P4ha1(+/-);P4ha2(-/-) mice. They were smaller than their littermates, had moderate chondrodysplasia, and developed kyphosis. A transient inner cell death phenotype was detected in their developing growth plates. The columnar arrangement of proliferative chondrocytes was impaired, the amount of 4-hydroxyproline and the Tm of collagen II were reduced, and the extracellular matrix was softer in the growth plates of newborn P4ha1(+/-);P4ha2(-/-) mice. No signs of uncompensated ER stress were detected in the mutant growth plate chondrocytes. Some of these defects were also found in P4ha2(-/-) mice, although in a much milder form. Our data show that C-P4H-I can to a large extent compensate for the lack of C-P4H-II in proper endochondral bone development, but their combined partial and complete inactivation, respectively, leads to biomechanically impaired extracellular matrix, moderate chondrodysplasia, and kyphosis. Our mouse data suggest that inactivating mutations in human P4HA2 are not likely to lead to skeletal disorders, and a simultaneous decrease in P4HA1 function would most probably be required to generate such a disease phenotype. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. A lack of immune system genes causes loss in high frequency hearing but does not disrupt cochlear synapse maturation in mice.

    Science.gov (United States)

    Calton, Melissa A; Lee, Dasom; Sundaresan, Srividya; Mendus, Diana; Leu, Rose; Wangsawihardja, Felix; Johnson, Kenneth R; Mustapha, Mirna

    2014-01-01

    Early cochlear development is marked by an exuberant outgrowth of neurites that innervate multiple targets. The establishment of mature cochlear neural circuits is, however, dependent on the pruning of inappropriate axons and synaptic connections. Such refinement also occurs in the central nervous system (CNS), and recently, genes ordinarily associated with immune and inflammatory processes have been shown to play roles in synaptic pruning in the brain. These molecules include the major histocompatibility complex class I (MHCI) genes, H2-K(b) and H2-D(b), and the complement cascade gene, C1qa. Since the mechanisms involved in synaptic refinement in the cochlea are not well understood, we investigated whether these immune system genes may be involved in this process and whether they are required for normal hearing function. Here we report that these genes are not necessary for normal synapse formation and refinement in the mouse cochlea. We further demonstrate that C1qa expression is not necessary for normal hearing in mice but the lack of expression of H2-K(b) and H2-D(b) causes hearing impairment. These data underscore the importance of the highly polymorphic family of MHCI genes in hearing in mice and also suggest that factors and mechanisms regulating synaptic refinement in the cochlea may be distinct from those in the CNS.

  12. Normal autophagic activity in macrophages from mice lacking Gαi3, AGS3, or RGS19.

    Directory of Open Access Journals (Sweden)

    Ali Vural

    Full Text Available In macrophages autophagy assists antigen presentation, affects cytokine release, and promotes intracellular pathogen elimination. In some cells autophagy is modulated by a signaling pathway that employs Gαi3, Activator of G-protein Signaling-3 (AGS3/GPSM1, and Regulator of G-protein Signaling 19 (RGS19. As macrophages express each of these proteins, we tested their importance in regulating macrophage autophagy. We assessed LC3 processing and the formation of LC3 puncta in bone marrow derived macrophages prepared from wild type, Gnai3(-/-, Gpsm1(-/-, or Rgs19(-/- mice following amino acid starvation or Nigericin treatment. In addition, we evaluated rapamycin-induced autophagic proteolysis rates by long-lived protein degradation assays and anti-autophagic action after rapamycin induction in wild type, Gnai3(-/-, and Gpsm1(-/- macrophages. In similar assays we compared macrophages treated or not with pertussis toxin, an inhibitor of GPCR (G-protein couple receptor triggered Gαi nucleotide exchange. Despite previous findings, the level of basal autophagy, autophagic induction, autophagic flux, autophagic degradation and the anti-autophagic action in macrophages that lacked Gαi3, AGS3, or RGS19; or had been treated with pertussis toxin, were similar to controls. These results indicate that while Gαi signaling may impact autophagy in some cell types it does not in macrophages.

  13. Antidepressive and BDNF effects of enriched environment treatment across ages in mice lacking BDNF expression through promoter IV

    Science.gov (United States)

    Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K

    2016-01-01

    Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0–2 months), young adult (2–4 months), and old adult (12–14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918

  14. Generation of mice lacking DUF1220 protein domains: effects on fecundity and hyperactivity

    Science.gov (United States)

    Keeney, JG; O’Bleness, MS; Anderson, N; Davis, JM; Arevalo, N; Busquet, N; Chick, W; Rozman, J; Hölter, SM; Garrett, L; Horsch, M; Beckers, J; Wurst, W; Klingenspor, M; Restrepo, D

    2014-01-01

    Sequences encoding DUF1220 protein domains show the most extreme human lineage-specific copy number increase of any coding region in the genome and have been linked to human brain evolution. In addition, DUF1220 copy number (dosage) has been implicated in influencing brain size within the human species, both in normal populations and in individuals associated with brain size pathologies (1q21-associated microcephaly and macrocephaly). More recently, increasing dosage of a subtype of DUF1220 has been linked with increasing severity of the primary symptoms of autism. Despite these intriguing associations, a function for these domains has not been described. As a first step in addressing this question we have developed the first transgenic model of DUF1220 function by removing the single DUF1220 domain (the ancestral form) encoded in the mouse genome. In a hypothesis generating exercise, these mice were evaluated by 197 different phenotype measurements. While resulting DUF1220-minus (KO) mice show no obvious anatomical peculiarities, they exhibit a significantly reduced fecundity (χ2= 19.1, df = 2, p = 7.0 × 10−5). Further extensive phenotypic analyses suggest hyperactivity (p < 0.05) of DUF1220 mice and changes in gene expression levels of brain associated with distinct neurological functions and disease. Other changes that met statistical significance include an increase in plasma glucose concentration (as measured by Area Under the Curve, AUC 0-30 and AUC 30-120) in male mutants, fasting glucose levels, reduce sodium levels in male mutants, increased levels of the liver functional indicator ALAT/GPT in males, levels of alkaline phosphatase (also an indicator of liver function), mean R and SR amplitude by electrocardiography, elevated IgG3 levels, a reduced ratio of CD4:CD8 cells, and a reduced frequency of T cells; though it should be noted that many of these differences are quite small and require further examination. The linking of DUF1220 loss to a

  15. Generation of mice lacking DUF1220 protein domains: effects on fecundity and hyperactivity.

    Science.gov (United States)

    Keeney, J G; O'Bleness, M S; Anderson, N; Davis, J M; Arevalo, N; Busquet, N; Chick, W; Rozman, J; Hölter, S M; Garrett, L; Horsch, M; Beckers, J; Wurst, W; Klingenspor, M; Restrepo, D; de Angelis, M Hrabě; Sikela, J M

    2015-02-01

    Sequences encoding DUF1220 protein domains show the most extreme human lineage-specific copy number increase of any coding region in the genome and have been linked to human brain evolution. In addition, DUF1220 copy number (dosage) has been implicated in influencing brain size within the human species, both in normal populations and in individuals associated with brain size pathologies (1q21-associated microcephaly and macrocephaly). More recently, increasing dosage of a subtype of DUF1220 has been linked with increasing severity of the primary symptoms of autism. Despite these intriguing associations, a function for these domains has not been described. As a first step in addressing this question, we have developed the first transgenic model of DUF1220 function by removing the single DUF1220 domain (the ancestral form) encoded in the mouse genome. In a hypothesis generating exercise, these mice were evaluated by 197 different phenotype measurements. While resulting DUF1220-minus (KO) mice show no obvious anatomical peculiarities, they exhibit a significantly reduced fecundity (χ(2) = 19.1, df = 2, p = 7.0 × 10(-5)). Further extensive phenotypic analyses suggest hyperactivity (p < 0.05) of DUF1220 mice and changes in gene expression levels of brain associated with distinct neurological functions and disease. Other changes that met statistical significance include an increase in plasma glucose concentration (as measured by area under the curve, AUC 0-30 and AUC 30-120) in male mutants, fasting glucose levels, reduce sodium levels in male mutants, increased levels of the liver functional indicator ALAT/GPT in males, levels of alkaline phosphatase (also an indicator of liver function), mean R and SR amplitude by electrocardiography, elevated IgG3 levels, a reduced ratio of CD4:CD8 cells, and a reduced frequency of T cells; though it should be noted that many of these differences are quite small and require further examination. The linking of DUF1220 loss to a

  16. Communication impairments in mice lacking Shank1: reduced levels of ultrasonic vocalizations and scent marking behavior.

    Directory of Open Access Journals (Sweden)

    Markus Wöhr

    Full Text Available Autism is a neurodevelopmental disorder with a strong genetic component. Core symptoms are abnormal reciprocal social interactions, qualitative impairments in communication, and repetitive and stereotyped patterns of behavior with restricted interests. Candidate genes for autism include the SHANK gene family, as mutations in SHANK2 and SHANK3 have been detected in several autistic individuals. SHANK genes code for a family of scaffolding proteins located in the postsynaptic density of excitatory synapses. To test the hypothesis that a mutation in SHANK1 contributes to the symptoms of autism, we evaluated Shank1(-/- null mutant mice for behavioral phenotypes with relevance to autism, focusing on social communication. Ultrasonic vocalizations and the deposition of scent marks appear to be two major modes of mouse communication. Our findings revealed evidence for low levels of ultrasonic vocalizations and scent marks in Shank1(-/- mice as compared to wildtype Shank1(+/+ littermate controls. Shank1(-/- pups emitted fewer vocalizations than Shank1(+/+ pups when isolated from mother and littermates. In adulthood, genotype affected scent marking behavior in the presence of female urinary pheromones. Adult Shank1(-/- males deposited fewer scent marks in proximity to female urine than Shank1(+/+ males. Call emission in response to female urinary pheromones also differed between genotypes. Shank1(+/+ mice changed their calling pattern dependent on previous female interactions, while Shank1(-/- mice were unaffected, indicating a failure of Shank1(-/- males to learn from a social experience. The reduced levels of ultrasonic vocalizations and scent marking behavior in Shank1(-/- mice are consistent with a phenotype relevant to social communication deficits in autism.

  17. IGF-II is up-regulated and myofibres are hypertrophied in regenerating soleus of mice lacking FGF6

    International Nuclear Information System (INIS)

    Armand, Anne-Sophie; Lecolle, Sylvie; Launay, Thierry; Pariset, Claude; Fiore, Frederic; Della Gaspera, Bruno; Birnbaum, Daniel; Chanoine, Christophe; Charbonnier, Frederic

    2004-01-01

    Important functions in myogenesis have been proposed for FGF6, a member of the fibroblast growth factor family accumulating almost exclusively in the myogenic lineage. However, the use of FGF6(-/-) mutant mice gave contradictory results and the role of FGF6 during myogenesis remains largely unclear. Using FGF6(-/-) mice, we first analysed the morphology of the regenerated soleus following cardiotoxin injection and showed hypertrophied myofibres in soleus of the mutant mice as compared to wild-type mice. Secondly, to examine the function of the IGF family in the hypertrophy process, we used semiquantitative and real-time RT-PCR assays and Western blots to monitor the expression of the insulin-like growth factors (IGF-I and IGF-II), their receptors [type I IGF receptor (IGF1R) and IGF-II receptor (IGF2R)], and of a binding protein IGFBP-5 in regenerating soleus muscles of FGF6(-/-) knockout mice vs. wild-type mice. In the mutant, both IGF-II and IGF2R, but not IGF-I and IGF1R, were strongly up-regulated, whereas IGFBP5 was down-regulated, strongly suggesting that, in the absence of FGF6, the mechanisms leading to myofibre hypertrophy were mediated specifically by an IGF-II/IGF2R signalling pathway distinct from the classic mechanism involving IGF-I and IGF1R previously described for skeletal muscle hypertrophy. The potential regulating role of IGFBP5 on IGF-II expression is also discussed. This report shows for the first time a specific role for FGF6 in the regulation of myofibre size during a process of in vivo myogenesis

  18. Therapeutic cloning in individual parkinsonian mice

    Science.gov (United States)

    Tabar, Viviane; Tomishima, Mark; Panagiotakos, Georgia; Wakayama, Sayaka; Menon, Jayanthi; Chan, Bill; Mizutani, Eiji; Al-Shamy, George; Ohta, Hiroshi; Wakayama, Teruhiko; Studer, Lorenz

    2009-01-01

    Cell transplantation with embryonic stem (ES) cell progeny requires immunological compatibility with host tissue. ‘Therapeutic cloning’ is a strategy to overcome this limitation by generating nuclear transfer (nt)ES cells that are genetically matched to an individual. Here we establish the feasibility of treating individual mice via therapeutic cloning. Derivation of 187 ntES cell lines from 24 parkinsonian mice, dopaminergic differentiation, and transplantation into individually matched host mice showed therapeutic efficacy and lack of immunological response. PMID:18376409

  19. Acute agmatine administration, similar to ketamine, reverses depressive-like behavior induced by chronic unpredictable stress in mice.

    Science.gov (United States)

    Neis, Vivian B; Bettio, Luis E B; Moretti, Morgana; Rosa, Priscila B; Ribeiro, Camille M; Freitas, Andiara E; Gonçalves, Filipe M; Leal, Rodrigo B; Rodrigues, Ana Lúcia S

    Agmatine is an endogenous neuromodulator that has been shown to have antidepressant-like properties. We have previously demonstrated that it can induce a rapid increase in BDNF levels after acute administration, suggesting that agmatine may be a fast-acting antidepressant. To investigate this hypothesis, the present study evaluated the effects of a single administration of agmatine in mice subjected to chronic unpredictable stress (CUS), a model of depression responsive only to chronic treatment with conventional antidepressants. The ability of agmatine to reverse CUS-induced behavioral and biochemical alterations was evaluated and compared with those elicited by the fast-acting antidepressant (ketamine) and the conventional antidepressant (fluoxetine). After exposed to CUS for 14days, mice received a single oral dose of agmatine (0.1mg/kg), ketamine (1mg/kg) or fluoxetine (10mg/kg), and were submitted to behavioral evaluation after 24h. The exposure to CUS caused an increased immobility time in the tail suspension test (TST) but did not change anhedonic-related parameters in the splash test. Our findings provided evidence that, similarly to ketamine, agmatine is able to reverse CUS-induced depressive-like behavior in the TST. Western blot analyses of prefrontal cortex (PFC) demonstrated that mice exposed to CUS and/or treated with agmatine, fluoxetine or ketamine did not present alterations in the immunocontent of synaptic proteins [i.e. GluA1, postsynaptic density protein 95 (PSD-95) and synapsin]. Altogether, our findings indicate that a single administration of agmatine is able to reverse behavioral alterations induced by CUS in the TST, suggesting that this compound may have fast-acting antidepressant-like properties. However, there was no alteration in the levels of synaptic proteins in the PFC, a result that need to be further investigated in other time points. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Communication Impairments in Mice Lacking Shank1: Reduced Levels of Ultrasonic Vocalizations and Scent Marking Behavior

    Science.gov (United States)

    Wöhr, Markus; Roullet, Florence I.; Hung, Albert Y.; Sheng, Morgan; Crawley, Jacqueline N.

    2011-01-01

    Autism is a neurodevelopmental disorder with a strong genetic component. Core symptoms are abnormal reciprocal social interactions, qualitative impairments in communication, and repetitive and stereotyped patterns of behavior with restricted interests. Candidate genes for autism include the SHANK gene family, as mutations in SHANK2 and SHANK3 have been detected in several autistic individuals. SHANK genes code for a family of scaffolding proteins located in the postsynaptic density of excitatory synapses. To test the hypothesis that a mutation in SHANK1 contributes to the symptoms of autism, we evaluated Shank1 −/− null mutant mice for behavioral phenotypes with relevance to autism, focusing on social communication. Ultrasonic vocalizations and the deposition of scent marks appear to be two major modes of mouse communication. Our findings revealed evidence for low levels of ultrasonic vocalizations and scent marks in Shank1 −/− mice as compared to wildtype Shank1 +/+ littermate controls. Shank1 −/− pups emitted fewer vocalizations than Shank1+/+ pups when isolated from mother and littermates. In adulthood, genotype affected scent marking behavior in the presence of female urinary pheromones. Adult Shank1 −/− males deposited fewer scent marks in proximity to female urine than Shank1+/+ males. Call emission in response to female urinary pheromones also differed between genotypes. Shank1+/+ mice changed their calling pattern dependent on previous female interactions, while Shank1 −/− mice were unaffected, indicating a failure of Shank1 −/− males to learn from a social experience. The reduced levels of ultrasonic vocalizations and scent marking behavior in Shank1 −/− mice are consistent with a phenotype relevant to social communication deficits in autism. PMID:21695253

  1. Dietary restriction ameliorates haematopoietic ageing independent of telomerase, whilst lack of telomerase and short telomeres exacerbates the ageing phenotype.

    Science.gov (United States)

    Al-Ajmi, Nouf; Saretzki, Gabriele; Miles, Colin; Spyridopoulos, Ioakim

    2014-10-01

    Ageing is associated with an overall decline in the functional capacity of tissues and stem cells, including haematopoietic stem and progenitor cells (HSPCs), as well as telomere dysfunction. Dietary restriction (DR) is a recognised anti-ageing intervention that extends lifespan and improves health in several organisms. To investigate the role of telomeres and telomerase in haematopoietic ageing, we compared the HSPC profile and clonogenic capacity of bone marrow cells from wild type with telomerase-deficient mice and the effect of DR on these parameters. Compared with young mice, aged wild type mice demonstrated a significant accumulation of HSPCs (1.3% vs 0.2%, P=0.002) and elevated numbers of granulocyte/macrophage colony forming units (CFU-GM, 26.4 vs 17.3, P=0.0037) consistent with myeloid "skewing" of haematopoiesis. DR was able to restrict the increase in HSPC number as well as the myeloid "skewing" in aged wild type mice. In order to analyse the influence of short telomeres on the ageing phenotype we examined mice lacking the RNA template for telomerase, TERC(-/-). Telomere shortening resulted in a similar bone marrow phenotype to that seen in aged mice, with significantly increased HSPC numbers and an increased formation of all myeloid colony types but at a younger age than wild type mice. However, an additional increase in erythroid colonies (BFU-E) was also evident. Mice lacking telomerase reverse transcriptase without shortened telomeres, TERT(-/-), also presented with augmented haematopoietic ageing which was ameliorated by DR, demonstrating that the effect of DR was not dependent on the presence of telomerase in HSPCs. We conclude that whilst shortened telomeres mimic some aspects of haematopoietic ageing, both shortened telomeres and the lack of telomerase produce specific phenotypes, some of which can be prevented by dietary restriction. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Polygalasaponin XXXII from Polygala tenuifolia root improves hippocampal-dependent learning and memory.

    Science.gov (United States)

    Xue, Wei; Hu, Jin-feng; Yuan, Yu-he; Sun, Jian-dong; Li, Bo-yu; Zhang, Dong-ming; Li, Chuang-jun; Chen, Nai-hong

    2009-09-01

    The aim of this study was to investigate the cognition-enhancing activity and underlying mechanisms of a triterpenoid saponin (polygalasaponin XXXII, PGS32) isolated from the roots of Polygala tenuifolia Willd. The Morris water maze was used to evaluate the spatial learning and memory of mice. To detect the basic properties of synaptic transmission and long-term potentiation (LTP) in the dentate gyrus of rats, electrophysiological recordings were made of evoked potentials. Western blotting analysis and immunofluorescence assays were used to determine the phosphorylation of extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), synapsin I and the expression of brain derived neurotrophic factor (BDNF). When administered at 0.125, 0.5, or 2 mg/kg, PGS32 could significantly prevent scopolamine-induced cognitive impairments in mice. Intracerebroventricular (icv) administration of PGS32 greatly enhanced basic synaptic transmission in the dentate gyrus of rats and induced LTP. In primary hippocampal neurons, as well as in the hippocampus of maze-trained mice, PGS32 activated the mitogen-activated protein (MAP) kinase cascade by promoting phosphorylation of ERK, CREB and synapsin I. The expression of BDNF was also greatly enhanced in the hippocampus. Our findings suggest that PGS32 can improve hippocampus-dependent learning and memory, possibly through improvement of synaptic transmission, activation of the MAP kinase cascade and enhancement of the level of BDNF. Therefore, PGS32 shows promise as a potential cognition-enhancing therapeutic drug.

  3. Atypical scrapie prions from sheep and lack of disease in transgenic mice overexpressing human prion protein.

    Science.gov (United States)

    Wadsworth, Jonathan D F; Joiner, Susan; Linehan, Jacqueline M; Balkema-Buschmann, Anne; Spiropoulos, John; Simmons, Marion M; Griffiths, Peter C; Groschup, Martin H; Hope, James; Brandner, Sebastian; Asante, Emmanuel A; Collinge, John

    2013-11-01

    Public and animal health controls to limit human exposure to animal prions are focused on bovine spongiform encephalopathy (BSE), but other prion strains in ruminants may also have zoonotic potential. One example is atypical/Nor98 scrapie, which evaded statutory diagnostic methods worldwide until the early 2000s. To investigate whether sheep infected with scrapie prions could be another source of infection, we inoculated transgenic mice that overexpressed human prion protein with brain tissue from sheep with natural field cases of classical and atypical scrapie, sheep with experimental BSE, and cattle with BSE. We found that these mice were susceptible to BSE prions, but disease did not develop after prolonged postinoculation periods when mice were inoculated with classical or atypical scrapie prions. These data are consistent with the conclusion that prion disease is less likely to develop in humans after exposure to naturally occurring prions of sheep than after exposure to epizootic BSE prions of ruminants.

  4. Lack of Glycogenin Causes Glycogen Accumulation and Muscle Function Impairment.

    Science.gov (United States)

    Testoni, Giorgia; Duran, Jordi; García-Rocha, Mar; Vilaplana, Francisco; Serrano, Antonio L; Sebastián, David; López-Soldado, Iliana; Sullivan, Mitchell A; Slebe, Felipe; Vilaseca, Marta; Muñoz-Cánoves, Pura; Guinovart, Joan J

    2017-07-05

    Glycogenin is considered essential for glycogen synthesis, as it acts as a primer for the initiation of the polysaccharide chain. Against expectations, glycogenin-deficient mice (Gyg KO) accumulate high amounts of glycogen in striated muscle. Furthermore, this glycogen contains no covalently bound protein, thereby demonstrating that a protein primer is not strictly necessary for the synthesis of the polysaccharide in vivo. Strikingly, in spite of the higher glycogen content, Gyg KO mice showed lower resting energy expenditure and less resistance than control animals when subjected to endurance exercise. These observations can be attributed to a switch of oxidative myofibers toward glycolytic metabolism. Mice overexpressing glycogen synthase in the muscle showed similar alterations, thus indicating that this switch is caused by the excess of glycogen. These results may explain the muscular defects of GSD XV patients, who lack glycogenin-1 and show high glycogen accumulation in muscle. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. PERCEPTION OF SWEET TASTE IS IMPORTANT FOR VOLUNTARY ALCOHOL CONSUMPTION IN MICE

    OpenAIRE

    Blednov, Y.A.; Walker, D.; Martinez, M.; Levine, M.; Damak, S.; Margolskee, R.F.

    2007-01-01

    To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: α-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solution...

  6. Mice lacking desmocollin 1 show epidermal fragility accompanied by barrier defects and abnormal differentiation

    DEFF Research Database (Denmark)

    Chidgey, M; Brakebusch, C; Gustafsson, E

    2001-01-01

    epidermis because environmental insults are more stringent and wound healing is less rapid than in neonatal mice. This dermatitis is accompanied by localized hair loss associated with formation of utriculi and dermal cysts, denoting hair follicle degeneration. Possible resemblance of the lesions to human...

  7. Male mice that lack the G-protein-coupled receptor GPR41 have low energy expenditure and increased body fat content.

    Science.gov (United States)

    Bellahcene, Mohamed; O'Dowd, Jacqueline F; Wargent, Ed T; Zaibi, Mohamed S; Hislop, David C; Ngala, Robert A; Smith, David M; Cawthorne, Michael A; Stocker, Claire J; Arch, Jonathan R S

    2013-05-28

    SCFA are produced in the gut by bacterial fermentation of undigested carbohydrates. Activation of the Gαi-protein-coupled receptor GPR41 by SCFA in β-cells and sympathetic ganglia inhibits insulin secretion and increases sympathetic outflow, respectively. A possible role in stimulating leptin secretion by adipocytes is disputed. In the present study, we investigated energy balance and glucose homoeostasis in GPR41 knockout mice fed on a standard low-fat or a high-fat diet. When fed on the low-fat diet, body fat mass was raised and glucose tolerance was impaired in male but not female knockout mice compared to wild-type mice. Soleus muscle and heart weights were reduced in the male mice, but total body lean mass was unchanged. When fed on the high-fat diet, body fat mass was raised in male but not female GPR41 knockout mice, but by no more in the males than when they were fed on the low-fat diet. Body lean mass and energy expenditure were reduced in male mice but not in female knockout mice. These results suggest that the absence of GPR41 increases body fat content in male mice. Gut-derived SCFA may raise energy expenditure and help to protect against obesity by activating GPR41.

  8. Lack of carcinogenicity of tragacanth gum in B6C3F1 mice.

    Science.gov (United States)

    Hagiwara, A; Boonyaphiphat, P; Kawabe, M; Naito, H; Shirai, T; Ito, N

    1992-08-01

    Tragacanth gum was administered at dietary levels of 0 (control), 1.25 and 5.0% to groups of 50 male and 50 female B6C3F1 mice for 96 wk after which all animals were maintained on a basal diet without tragacanth gum for a further 10 wk. Mean body weights of females in the 5.0% and 1.25% groups were lower than those of the controls after 11 and 16 wk, respectively. However, there were no treatment-related clinical signs or adverse effects on survival rate, urinalysis, haematology, blood biochemistry and organ weight. While detailed histopathology revealed the development of squamous cell hyperplasias, papillomas and one carcinoma in the forestomach, there was no significant treatment-related increase in the incidence of any preneoplastic or neoplastic lesion. Thus, under the experimental conditions used, tragacanth gum was not carcinogenic in B6C3F1 mice of either sex.

  9. Not So Giants: Mice Lacking Both Somatostatin and Cortistatin Have High GH Levels but Show No Changes in Growth Rate or IGF-1 Levels.

    Science.gov (United States)

    Pedraza-Arévalo, S; Córdoba-Chacón, J; Pozo-Salas, A I; L-López, F; de Lecea, L; Gahete, M D; Castaño, J P; Luque, R M

    2015-06-01

    Somatostatin (SST) and cortistatin (CORT) are two highly related neuropeptides involved in the regulation of various endocrine secretions. In particular, SST and CORT are two primary negative regulators of GH secretion. Consequently, single SST or CORT knockout mice exhibit elevated GH levels; however, this does not lead to increased IGF-1 levels or somatic growth. This apparent lack of correspondence has been suggested to result from compensatory mechanisms between both peptides. To test this hypothesis, in this study we explored, for the first time, the consequences of simultaneously deleting endogenous SST and CORT by generating a double SST/CORT knockout mouse model and exploring its endocrine and metabolic phenotype. Our results demonstrate that simultaneous deletion of SST and CORT induced a drastic elevation of endogenous GH levels, which, surprisingly, did not lead to changes in growth rate or IGF-1 levels, suggesting the existence of additional factors/systems that, in the absence of endogenous SST and CORT, could counteract GH actions. Notably, elevation in circulating GH levels were not accompanied by changes in pituitary GH expression or by alterations in the expression of its main regulators (GHRH and ghrelin) or their receptors (GHRH receptor, GHS receptor, or SST/CORT receptors) at the hypothalamic or pituitary level. However, although double-SST/CORT knockout male mice exhibited normal glucose and insulin levels, they had improved insulin sensitivity compared with the control mice. Therefore, these results suggest the existence of an intricate interplay among the known (SST/CORT), and likely unknown, inhibitory components of the GH/IGF-1 axis to regulate somatic growth and glucose/insulin homeostasis.

  10. Induction of Neuron-Specific Degradation of Coenzyme A Models Pantothenate Kinase-Associated Neurodegeneration by Reducing Motor Coordination in Mice.

    Directory of Open Access Journals (Sweden)

    Stephanie A Shumar

    Full Text Available Pantothenate kinase-associated neurodegeneration, PKAN, is an inherited disorder characterized by progressive impairment in motor coordination and caused by mutations in PANK2, a human gene that encodes one of four pantothenate kinase (PanK isoforms. PanK initiates the synthesis of coenzyme A (CoA, an essential cofactor that plays a key role in energy metabolism and lipid synthesis. Most of the mutations in PANK2 reduce or abolish the activity of the enzyme. This evidence has led to the hypothesis that lower CoA might be the underlying cause of the neurodegeneration in PKAN patients; however, no mouse model of the disease is currently available to investigate the connection between neuronal CoA levels and neurodegeneration. Indeed, genetic and/or dietary manipulations aimed at reducing whole-body CoA synthesis have not produced a desirable PKAN model, and this has greatly hindered the discovery of a treatment for the disease.Cellular CoA levels are tightly regulated by a balance between synthesis and degradation. CoA degradation is catalyzed by two peroxisomal nudix hydrolases, Nudt7 and Nudt19. In this study we sought to reduce neuronal CoA in mice through the alternative approach of increasing Nudt7-mediated CoA degradation. This was achieved by combining the use of an adeno-associated virus-based expression system with the synapsin (Syn promoter. We show that mice with neuronal overexpression of a cytosolic version of Nudt7 (scAAV9-Syn-Nudt7cyt exhibit a significant decrease in brain CoA levels in conjunction with a reduction in motor coordination. These results strongly support the existence of a link between CoA levels and neuronal function and show that scAAV9-Syn-Nudt7cyt mice can be used to model PKAN.

  11. Characterization of inducible models of Tay-Sachs and related disease.

    Science.gov (United States)

    Sargeant, Timothy J; Drage, Deborah J; Wang, Susan; Apostolakis, Apostolos A; Cox, Timothy M; Cachón-González, M Begoña

    2012-09-01

    Tay-Sachs and Sandhoff diseases are lethal inborn errors of acid β-N-acetylhexosaminidase activity, characterized by lysosomal storage of GM2 ganglioside and related glycoconjugates in the nervous system. The molecular events that lead to irreversible neuronal injury accompanied by gliosis are unknown; but gene transfer, when undertaken before neurological signs are manifest, effectively rescues the acute neurodegenerative illness in Hexb-/- (Sandhoff) mice that lack β-hexosaminidases A and B. To define determinants of therapeutic efficacy and establish a dynamic experimental platform to systematically investigate cellular pathogenesis of GM2 gangliosidosis, we generated two inducible experimental models. Reversible transgenic expression of β-hexosaminidase directed by two promoters, mouse Hexb and human Synapsin 1 promoters, permitted progression of GM2 gangliosidosis in Sandhoff mice to be modified at pre-defined ages. A single auto-regulatory tetracycline-sensitive expression cassette controlled expression of transgenic Hexb in the brain of Hexb-/- mice and provided long-term rescue from the acute neuronopathic disorder, as well as the accompanying pathological storage of glycoconjugates and gliosis in most parts of the brain. Ultimately, late-onset brainstem and ventral spinal cord pathology occurred and was associated with increased tone in the limbs. Silencing transgenic Hexb expression in five-week-old mice induced stereotypic signs and progression of Sandhoff disease, including tremor, bradykinesia, and hind-limb paralysis. As in germline Hexb-/- mice, these neurodegenerative manifestations advanced rapidly, indicating that the pathogenesis and progression of GM2 gangliosidosis is not influenced by developmental events in the maturing nervous system.

  12. Characterization of inducible models of Tay-Sachs and related disease.

    Directory of Open Access Journals (Sweden)

    Timothy J Sargeant

    2012-09-01

    Full Text Available Tay-Sachs and Sandhoff diseases are lethal inborn errors of acid β-N-acetylhexosaminidase activity, characterized by lysosomal storage of GM2 ganglioside and related glycoconjugates in the nervous system. The molecular events that lead to irreversible neuronal injury accompanied by gliosis are unknown; but gene transfer, when undertaken before neurological signs are manifest, effectively rescues the acute neurodegenerative illness in Hexb-/- (Sandhoff mice that lack β-hexosaminidases A and B. To define determinants of therapeutic efficacy and establish a dynamic experimental platform to systematically investigate cellular pathogenesis of GM2 gangliosidosis, we generated two inducible experimental models. Reversible transgenic expression of β-hexosaminidase directed by two promoters, mouse Hexb and human Synapsin 1 promoters, permitted progression of GM2 gangliosidosis in Sandhoff mice to be modified at pre-defined ages. A single auto-regulatory tetracycline-sensitive expression cassette controlled expression of transgenic Hexb in the brain of Hexb-/- mice and provided long-term rescue from the acute neuronopathic disorder, as well as the accompanying pathological storage of glycoconjugates and gliosis in most parts of the brain. Ultimately, late-onset brainstem and ventral spinal cord pathology occurred and was associated with increased tone in the limbs. Silencing transgenic Hexb expression in five-week-old mice induced stereotypic signs and progression of Sandhoff disease, including tremor, bradykinesia, and hind-limb paralysis. As in germline Hexb-/- mice, these neurodegenerative manifestations advanced rapidly, indicating that the pathogenesis and progression of GM2 gangliosidosis is not influenced by developmental events in the maturing nervous system.

  13. Delayed contraction of the CD8+ T cell response toward lymphocytic choriomeningitis virus infection in mice lacking serglycin

    DEFF Research Database (Denmark)

    Grujic, Mirjana; Christensen, Jan P; Sørensen, Maria R

    2008-01-01

    (-/-)) mice with lymphocytic choriomeningitis virus (LCMV). Wt and SG(-/-) mice cleared 10(3) PFU of highly invasive LCMV with the same kinetics, and the CD8(+) T lymphocytes from wt and SG(-/-) animals did not differ in GrB, perforin, IFN-gamma, or TNF-alpha content. However, when a less invasive LCMV strain...

  14. Mice Lacking the β2 Adrenergic Receptor Have a Unique Genetic Profile before and after Focal Brain Ischaemia

    Directory of Open Access Journals (Sweden)

    Robin E White

    2012-08-01

    Full Text Available The role of the β2AR (β2 adrenergic receptor after stroke is unclear as pharmacological manipulations of the β2AR have produced contradictory results. We previously showed that mice deficient in the β2AR (β2KO had smaller infarcts compared with WT (wild-type mice (FVB after MCAO (middle cerebral artery occlusion, a model of stroke. To elucidate mechanisms of this neuroprotection, we evaluated changes in gene expression using microarrays comparing differences before and after MCAO, and differences between genotypes. Genes associated with inflammation and cell deaths were enriched after MCAO in both genotypes, and we identified several genes not previously shown to increase following ischaemia (Ccl9, Gem and Prg4. In addition to networks that were similar between genotypes, one network with a central core of GPCR (G-protein-coupled receptor and including biological functions such as carbohydrate metabolism, small molecule biochemistry and inflammation was identified in FVB mice but not in β2KO mice. Analysis of differences between genotypes revealed 11 genes differentially expressed by genotype both before and after ischaemia. We demonstrate greater Glo1 protein levels and lower Pmaip/Noxa mRNA levels in β2KO mice in both sham and MCAO conditions. As both genes are implicated in NF-κB (nuclear factor κB signalling, we measured p65 activity and TNFα (tumour necrosis factor α levels 24 h after MCAO. MCAO-induced p65 activation and post-ischaemic TNFα production were both greater in FVB compared with β2KO mice. These results suggest that loss of β2AR signaling results in a neuroprotective phenotype in part due to decreased NF-κB signalling, decreased inflammation and decreased apoptotic signalling in the brain.

  15. Environmental enrichment reduces innate anxiety with no effect on depression-like behaviour in mice lacking the serotonin transporter.

    Science.gov (United States)

    Rogers, Jake; Li, Shanshan; Lanfumey, Laurence; Hannan, Anthony J; Renoir, Thibault

    2017-08-14

    Along with being the main target of many antidepressant medications, the serotonin transporter (5-HTT) is known to be involved in the pathophysiology of depression and anxiety disorders. In line with this, mice with varying 5-HTT genotypes are invaluable tools to study depression- and anxiety-like behaviours as well as the mechanisms mediating potential therapeutics. There is clear evidence that both genetic and environmental factors play a role in the aetiology of psychiatric disorders. In that regard, housing paradigms which seek to enhance cognitive stimulation and physical activity have been shown to exert beneficial effects in animal models of neuropsychiatric disorders. In the present study, we examined the effects of environmental enrichment on affective-like behaviours and sensorimotor gating function of 5-HTT knock-out (KO) mice. Using the elevated-plus maze and the light-dark box, we found that environmental enrichment ameliorated the abnormal innate anxiety of 5-HTT KO mice on both tests. In contrast, environmental enrichment did not rescue the depression-like behaviour displayed by 5-HTT KO mice in the forced-swim test. Finally, measuring pre-pulse inhibition, we found no effect of genotype or treatment on sensorimotor gating. In conclusion, our data suggest that environmental enrichment specifically reduces innate anxiety of 5-HTT KO mice with no amelioration of the depression-like behaviour. This has implications for the current use of clinical interventions for patients with symptoms of both anxiety and depression. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Lack of a Functioning P2X7 Receptor Leads to Increased Susceptibility to Toxoplasmic Ileitis.

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    Catherine M Miller

    Full Text Available Oral infection of C57BL/6J mice with the protozoan parasite Toxoplasma gondii leads to a lethal inflammatory ileitis.Mice lacking the purinergic receptor P2X7R are acutely susceptible to toxoplasmic ileitis, losing significantly more weight than C57BL/6J mice and exhibiting much greater intestinal inflammatory pathology in response to infection with only 10 cysts of T. gondii. This susceptibility is not dependent on the ability of P2X7R-deficient mice to control the parasite, which they accomplish just as efficiently as C57BL/6J mice. Rather, susceptibility is associated with elevated ileal concentrations of pro-inflammatory cytokines, reactive nitrogen intermediates and altered regulation of elements of NFκB activation in P2X7R-deficient mice.Our data support the thesis that P2X7R, a well-documented activator of pro-inflammatory cytokine production, also plays an important role in the regulation of intestinal inflammation.

  17. Development of mice without Cip/Kip CDK inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Tateishi, Yuki; Matsumoto, Akinobu; Kanie, Tomoharu [Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Hara, Eiji [Cancer Institute, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakayama, Keiko [Department of Developmental Genetics, Center for Translational and Advanced Animal Research, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 (Japan); Nakayama, Keiichi I., E-mail: nakayak1@bioreg.kyushu-u.ac.jp [Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan)

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer Mice lacking Cip/Kip CKIs (p21, p27, and p57) survive until embryonic day 13.5. Black-Right-Pointing-Pointer Proliferation of MEFs lacking all three Cip/Kip CKIs appears unexpectedly normal. Black-Right-Pointing-Pointer CDK2 kinase activity of the triple mutant MEFs is increased in G0 phase. -- Abstract: Timely exit of cells from the cell cycle is essential for proper cell differentiation during embryogenesis. Cyclin-dependent kinase (CDK) inhibitors (CKIs) of the Cip/Kip family (p21, p27, and p57) are negative regulators of cell cycle progression and are thought to be essential for development. However, the extent of functional redundancy among Cip/Kip family members has remained largely unknown. We have now generated mice that lack all three Cip/Kip CKIs (TKO mice) and compared them with those lacking each possible pair of these proteins (DKO mice). We found that the TKO embryos develop normally until midgestation but die around embryonic day (E) 13.5, slightly earlier than p27/p57 DKO embryos. The TKO embryos manifested morphological abnormalities as well as increased rates of cell proliferation and apoptosis in the placenta and lens that were essentially indistinguishable from those of p27/p57 DKO mice. Unexpectedly, the proliferation rate and cell cycle profile of mouse embryonic fibroblasts (MEFs) lacking all three Cip/Kip CKIs did not differ substantially from those of control MEFs. The abundance and kinase activity of CDK2 were markedly increased, whereas CDK4 activity and cyclin D1 abundance were decreased, in both p27/p57 DKO and TKO MEFs during progression from G{sub 0} to S phase compared with those in control MEFs. The extents of the increase in CDK2 activity and the decrease in CDK4 activity and cyclin D1 abundance were greater in TKO MEFs than in p27/p57 DKO MEFs. These results suggest that p27 and p57 play an essential role in mouse development after midgestation, and that p21 plays only an auxiliary role in

  18. Lack of the purinergic receptor P2X7 results in resistance to contact hypersensitivity

    Science.gov (United States)

    Weber, Felix C.; Esser, Philipp R.; Müller, Tobias; Ganesan, Jayanthi; Pellegatti, Patrizia; Simon, Markus M.; Zeiser, Robert; Idzko, Marco; Jakob, Thilo

    2010-01-01

    Sensitization to contact allergens requires activation of the innate immune system by endogenous danger signals. However, the mechanisms through which contact allergens activate innate signaling pathways are incompletely understood. In this study, we demonstrate that mice lacking the adenosine triphosphate (ATP) receptor P2X7 are resistant to contact hypersensitivity (CHS). P2X7-deficient dendritic cells fail to induce sensitization to contact allergens and do not release IL-1β in response to lipopolysaccharide (LPS) and ATP. These defects are restored by pretreatment with LPS and alum in an NLRP3- and ASC-dependent manner. Whereas pretreatment of wild-type mice with P2X7 antagonists, the ATP-degrading enzyme apyrase or IL-1 receptor antagonist, prevents CHS, IL-1β injection restores CHS in P2X7-deficient mice. Thus, P2X7 is a crucial receptor for extracellular ATP released in skin in response to contact allergens. The lack of P2X7 triggering prevents IL-1β release, which is an essential step in the sensitization process. Interference with P2X7 signaling may be a promising strategy for the prevention of allergic contact dermatitis. PMID:21059855

  19. Lack of the matricellular protein SPARC (secreted protein, acidic and rich in cysteine attenuates liver fibrogenesis in mice.

    Directory of Open Access Journals (Sweden)

    Catalina Atorrasagasti

    Full Text Available INTRODUCTION: Secreted Protein, Acidic and Rich in Cysteine (SPARC is a matricellular protein involved in many biological processes and found over-expressed in cirrhotic livers. By mean of a genetic approach we herein provide evidence from different in vivo liver disease models suggesting a profibrogenic role for SPARC. METHODS: Two in vivo models of liver fibrosis, based on TAA administration and bile duct ligation, were developed on SPARC wild-type (SPARC(+/+ and knock-out (SPARC(-/- mice. Hepatic SPARC expression was analyzed by qPCR. Fibrosis was assessed by Sirius Red staining, and the maturation state of collagen fibers was analyzed using polarized light. Necroinflammatory activity was evaluated by applying the Knodell score and liver inflammatory infiltration was characterized by immunohistochemistry. Hepatic stellate cell activation was assessed by α-SMA immunohistochemistry. In addition, pro-fibrogenic genes and inflammatory cytokines were measured by qPCR and/or ELISA. Liver gene expression profile was analyzed in SPARC(-/- and SPARC(+/+ mice using Affymetrix Mouse Gene ST 1.0 array. RESULTS: SPARC expression was found induced in fibrotic livers of mouse and human. SPARC(-/- mice showed a reduction in the degree of inflammation, mainly CD4+ cells, and fibrosis. Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/- mice when compared to SPARC(+/+ mice; in addition, MMP-2 expression was increased in SPARC(-/- mice. A reduction in the number of activated myofibroblasts was observed. Moreover, TGF-β1 expression levels were down-regulated in the liver as well as in the serum of TAA-treated knock-out animals. Ingenuity Pathway Analysis (IPA analysis suggested several gene networks which might involve protective mechanisms of SPARC deficiency against liver fibrogenesis and a better established machinery to repair DNA and detoxify from external chemical stimuli. CONCLUSIONS: Overall our data suggest that

  20. Fluoxetine regulates mTOR signalling in a region-dependent manner in depression-like mice

    Science.gov (United States)

    Liu, Xiao-Long; Luo, Liu; Mu, Rong-Hao; Liu, Bin-Bin; Geng, Di; Liu, Qing; Yi, Li-Tao

    2015-01-01

    Previous studies have demonstrated that the mammalian target of rapamycin (mTOR) signaling pathway has an important role in ketamine-induced, rapid antidepressant effects despite the acute administration of fluoxetine not affecting mTOR phosphorylation in the brain. However, the effects of long-term fluoxetine treatment on mTOR modulation have not been assessed to date. In the present study, we examined whether fluoxetine, a type of commonly used antidepressant agent, alters mTOR signaling following chronic administration in different brain regions, including the frontal cortex, hippocampus, amygdala and hypothalamus. We also investigated whether fluoxetine enhanced synaptic protein levels in these regions via the activation of the mTOR signaling pathway and its downstream regulators, p70S6K and 4E-BP-1. The results indicated that chronic fluoxetine treatment attenuated the chronic, unpredictable, mild stress (CUMS)-induced mTOR phosphorylation reduction in the hippocampus and amygdala of mice but not in the frontal cortex or the hypothalamus. Moreover, the CUMS-decreased PSD-95 and synapsin I levels were reversed by fluoxetine, and these effects were blocked by rapamycin only in the hippocampus. In conclusion, our findings suggest that chronic treatment with fluoxetine can induce synaptic protein expression by activating the mTOR signaling pathway in a region-dependent manner and mainly in the hippocampus. PMID:26522512

  1. Enhancement of immune response induced by DNA vaccine cocktail expressing complete LACK and TSA genes against Leishmania major.

    Science.gov (United States)

    Ghaffarifar, Fatemeh; Jorjani, Ogholniaz; Sharifi, Zohreh; Dalimi, Abdolhossein; Hassan, Zuhair M; Tabatabaie, Fatemeh; Khoshzaban, Fariba; Hezarjaribi, Hajar Ziaei

    2013-04-01

    Leishmaniasis is an important disease in humans. Leishmania homologue of receptor for Activated C Kinase (LACK) and thiol specific antioxidant (TSA) as immuno-dominant antigens of Leishmania major are considered the most promising molecules for a DNA vaccine. We constructed a DNA cocktail, containing plasmids encoding LACK and TSA genes of Leishmania major and evaluated the immune response and survival rate in BALB/c mice. IgG and Interferon gamma values were noticeably increased in the immunized group with DNA cocktail vaccine, which were significantly higher than those in the single-gene vaccinated and control groups (p 0.05). The immunized mice with the cocktail DNA vaccine presented a considerable reduction in diameter of lesion compared to other groups and a significant difference was observed (p < 0.05) in this regard. The survival time of the immunized mice with the cocktail DNA vaccine was significantly higher than that in the other groups (p < 0.05) after their being challenged with Leishmania major. The findings of this study indicated that the cocktail DNA vaccine increased the cellular response and survival rate and induced protection against infection with Leishmania in the mice. © 2012 The Authors © 2012 APMIS.

  2. The effect of alcohol and hydrogen peroxide on liver hepcidin gene expression in mice lacking antioxidant enzymes, glutathione peroxidase-1 or catalase.

    Science.gov (United States)

    Harrison-Findik, Duygu Dee; Lu, Sizhao

    2015-05-06

    This study investigates the regulation of hepcidin, the key iron-regulatory molecule, by alcohol and hydrogen peroxide (H2O2) in glutathione peroxidase-1 (gpx-1(-/-)) and catalase (catalase(-/-)) knockout mice. For alcohol studies, 10% ethanol was administered in the drinking water for 7 days. Gpx-1(-/-) displayed significantly higher hepatic H2O2 levels than catalase(-/-) compared to wild-type mice, as measured by 2'-7'-dichlorodihydrofluorescein diacetate (DCFH-DA). The basal level of liver hepcidin expression was attenuated in gpx-1(-/-) mice. Alcohol increased H2O2 production in catalase(-/-) and wild-type, but not gpx-1(-/-), mice. Hepcidin expression was inhibited in alcohol-fed catalase(-/-) and wild-type mice. In contrast, alcohol elevated hepcidin expression in gpx-1(-/-) mice. Gpx-1(-/-) mice also displayed higher level of basal liver CHOP protein expression than catalase(-/-) mice. Alcohol induced CHOP and to a lesser extent GRP78/BiP expression, but not XBP1 splicing or binding of CREBH to hepcidin gene promoter, in gpx-1(-/-) mice. The up-regulation of hepatic ATF4 mRNA levels, which was observed in gpx-1(-/-) mice, was attenuated by alcohol. In conclusion, our findings strongly suggest that H2O2 inhibits hepcidin expression in vivo. Synergistic induction of CHOP by alcohol and H2O2, in the absence of gpx-1, stimulates liver hepcidin gene expression by ER stress independent of CREBH.

  3. Changes in resting-state functional connectivity after stroke in a mouse brain lacking extracellular matrix components.

    Science.gov (United States)

    Quattromani, Miriana Jlenia; Hakon, Jakob; Rauch, Uwe; Bauer, Adam Q; Wieloch, Tadeusz

    2018-04-01

    In the brain, focal ischemia results in a local region of cell death and disruption of both local and remote functional neuronal networks. Tissue reorganization following stroke can be limited by factors such as extracellular matrix (ECM) molecules that prevent neuronal growth and synaptic plasticity. The brain's ECM plays a crucial role in network formation, development, and regeneration of the central nervous system. Further, the ECM is essential for proper white matter tract development and for the formation of structures called perineuronal nets (PNNs). PNNs mainly surround parvalbumin/GABA inhibitory interneurons, of importance for processing sensory information. Previous studies have shown that downregulating PNNs after stroke reduces the neurite-inhibitory environment, reactivates plasticity, and promotes functional recovery. Resting-state functional connectivity (RS-FC) within and across hemispheres has been shown to correlate with behavioral recovery after stroke. However, the relationship between PNNs and RS-FC has not been examined. Here we studied a quadruple knock-out mouse (Q4) that lacks four ECM components: brevican, neurocan, tenascin-C and tenascin-R. We applied functional connectivity optical intrinsic signal (fcOIS) imaging in Q4 mice and wild-type (129S1 mice) before and 14 days after photothrombotic stroke (PT) to understand how the lack of crucial ECM components affects neuronal networks and functional recovery after stroke. Limb-placement ability was evaluated at 2, 7 and 14 days of recovery through the paw-placement test. Q4 mice exhibited significantly impaired homotopic RS-FC compared to wild-type mice, especially in the sensory and parietal regions. Changes in RS-FC were significantly correlated with the number of interhemispheric callosal crossings in those same regions. PT caused unilateral damage to the sensorimotor cortex and deficits of tactile-proprioceptive placing ability in contralesional fore- and hindlimbs, but the two

  4. Mechanical Forces Exacerbate Periodontal Defects in Bsp-null Mice

    Science.gov (United States)

    Soenjaya, Y.; Foster, B.L.; Nociti, F.H.; Ao, M.; Holdsworth, D.W.; Hunter, G.K.; Somerman, M.J.

    2015-01-01

    Bone sialoprotein (BSP) is an acidic phosphoprotein with collagen-binding, cell attachment, and hydroxyapatite-nucleating properties. BSP expression in mineralized tissues is upregulated at onset of mineralization. Bsp-null (Bsp-/-) mice exhibit reductions in bone mineral density, bone turnover, osteoclast activation, and impaired bone healing. Furthermore, Bsp-/- mice have marked periodontal tissue breakdown, with a lack of acellular cementum leading to periodontal ligament detachment, extensive alveolar bone and tooth root resorption, and incisor malocclusion. We hypothesized that altered mechanical stress from mastication contributes to periodontal destruction observed in Bsp-/- mice. This hypothesis was tested by comparing Bsp-/- and wild-type mice fed with standard hard pellet diet or soft powder diet. Dentoalveolar tissues were analyzed using histology and micro–computed tomography. By 8 wk of age, Bsp-/- mice exhibited molar and incisor malocclusion regardless of diet. Bsp-/- mice with hard pellet diet exhibited high incidence (30%) of severe incisor malocclusion, 10% lower body weight, 3% reduced femur length, and 30% elevated serum alkaline phosphatase activity compared to wild type. Soft powder diet reduced severe incisor malocclusion incidence to 3% in Bsp-/- mice, supporting the hypothesis that occlusal loading contributed to the malocclusion phenotype. Furthermore, Bsp-/- mice in the soft powder diet group featured normal body weight, long bone length, and serum alkaline phosphatase activity, suggesting that tooth dysfunction and malnutrition contribute to growth and skeletal defects reported in Bsp-/- mice. Bsp-/- incisors also erupt at a slower rate, which likely leads to the observed thickened dentin and enhanced mineralization of dentin and enamel toward the apical end. We propose that the decrease in eruption rate is due to a lack of acellular cementum and associated defective periodontal attachment. These data demonstrate the importance of BSP

  5. Lack of CRH Affects the Behavior but Does Not Affect the Formation of Short-Term Memory.

    Science.gov (United States)

    Varejkova, Eva; Plananska, Eva; Myslivecek, Jaromir

    2018-01-01

    Corticotropin-releasing hormone (CRH) is involved in modification of synaptic transmission and affects spatial discrimination learning, i.e., affects the formation of memory in long-term aspect. Therefore, we have focused on CRH effect on short-term memory. We have used stress task avoidance (maze containing three zones: entrance, aversive, and neutral) and compared the behavior and short-term memory in wild-type mice and mice lacking CRH (CRH KO) experiencing one 120-min session of restraint stress. As control, non-stressed animals were used. As expected, the animals that experienced the stress situation tend to spend less time in the zone in which the restraint chamber was present. The animals spent more time in the neutral zone. There were significant differences in number of freezing bouts in the aversive and entrance zones in CRH KO animals. CRH KO control animals entered the neutral zone much more faster than WT control and spent more time immobile in the neutral zone than WT control. These data give evidence that lacking of CRH itself improves the ability of mice to escape away from potentially dangerous area (i.e., those in which the scent of stressed animal is present).

  6. Expression of GAD67 and Dlx5 in the taste buds of mice genetically lacking Mash1.

    Science.gov (United States)

    Kito-Shingaki, Ayae; Seta, Yuji; Toyono, Takashi; Kataoka, Shinji; Kakinoki, Yasuaki; Yanagawa, Yuchio; Toyoshima, Kuniaki

    2014-06-01

    It has been reported that a subset of type III taste cells express glutamate decarboxylase (GAD)67, which is a molecule that synthesizes gamma-aminobutyric acid (GABA), and that Mash1 could be a potential regulator of the development of GABAnergic neurons via Dlx transcription factors in the central nervous system. In this study, we investigated the expression of GAD67 and Dlx in the embryonic taste buds of the soft palate and circumvallate papilla using Mash1 knockout (KO)/GAD67-GFP knock-in mice. In the wild-type animal, a subset of type III taste cells contained GAD67 in the taste buds of the soft palate and the developing circumvallate papilla, whereas GAD67-expressing taste bud cells were missing from Mash1 KO mice. A subset of type III cells expressed mRNA for Dlx5 in the wild-type animals, whereas Dlx5-expressing cells were not evident in the apical part of the circumvallate papilla and taste buds in the soft palate of Mash1 KO mice. Our results suggest that Mash1 is required for the expression of GAD67 and Dlx5 in taste bud cells. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Mice lacking the transcriptional regulator Bhlhe40 have enhanced neuronal excitability and impaired synaptic plasticity in the hippocampus.

    Directory of Open Access Journals (Sweden)

    Kelly A Hamilton

    Full Text Available Bhlhe40 is a transcription factor that is highly expressed in the hippocampus; however, its role in neuronal function is not well understood. Here, we used Bhlhe40 null mice on a congenic C57Bl6/J background (Bhlhe40 KO to investigate the impact of Bhlhe40 on neuronal excitability and synaptic plasticity in the hippocampus. Bhlhe40 KO CA1 neurons had increased miniature excitatory post-synaptic current amplitude and decreased inhibitory post-synaptic current amplitude, indicating CA1 neuronal hyperexcitability. Increased CA1 neuronal excitability was not associated with increased seizure severity as Bhlhe40 KO relative to +/+ (WT control mice injected with the convulsant kainic acid. However, significant reductions in long term potentiation and long term depression at CA1 synapses were observed in Bhlhe40 KO mice, indicating impaired hippocampal synaptic plasticity. Behavioral testing for spatial learning and memory on the Morris Water Maze (MWM revealed that while Bhlhe40 KO mice performed similarly to WT controls initially, when the hidden platform was moved to the opposite quadrant Bhlhe40 KO mice showed impairments in relearning, consistent with decreased hippocampal synaptic plasticity. To investigate possible mechanisms for increased neuronal excitability and decreased synaptic plasticity, a whole genome mRNA expression profile of Bhlhe40 KO hippocampus was performed followed by a chromatin immunoprecipitation sequencing (ChIP-Seq screen of the validated candidate genes for Bhlhe40 protein-DNA interactions consistent with transcriptional regulation. Of the validated genes identified from mRNA expression analysis, insulin degrading enzyme (Ide had the most significantly altered expression in hippocampus and was significantly downregulated on the RNA and protein levels; although Bhlhe40 did not occupy the Ide gene by ChIP-Seq. Together, these findings support a role for Bhlhe40 in regulating neuronal excitability and synaptic plasticity in

  8. Lack of significant metabolic abnormalities in mice with liver-specific disruption of 11β-hydroxysteroid dehydrogenase type 1.

    LENUS (Irish Health Repository)

    Lavery, Gareth G

    2012-07-01

    Glucocorticoids (GC) are implicated in the development of metabolic syndrome, and patients with GC excess share many clinical features, such as central obesity and glucose intolerance. In patients with obesity or type 2 diabetes, systemic GC concentrations seem to be invariably normal. Tissue GC concentrations determined by the hypothalamic-pituitary-adrenal (HPA) axis and local cortisol (corticosterone in mice) regeneration from cortisone (11-dehydrocorticosterone in mice) by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme, principally expressed in the liver. Transgenic mice have demonstrated the importance of 11β-HSD1 in mediating aspects of the metabolic syndrome, as well as HPA axis control. In order to address the primacy of hepatic 11β-HSD1 in regulating metabolism and the HPA axis, we have generated liver-specific 11β-HSD1 knockout (LKO) mice, assessed biomarkers of GC metabolism, and examined responses to high-fat feeding. LKO mice were able to regenerate cortisol from cortisone to 40% of control and had no discernible difference in a urinary metabolite marker of 11β-HSD1 activity. Although circulating corticosterone was unaltered, adrenal size was increased, indicative of chronic HPA stimulation. There was a mild improvement in glucose tolerance but with insulin sensitivity largely unaffected. Adiposity and body weight were unaffected as were aspects of hepatic lipid homeostasis, triglyceride accumulation, and serum lipids. Additionally, no changes in the expression of genes involved in glucose or lipid homeostasis were observed. Liver-specific deletion of 11β-HSD1 reduces corticosterone regeneration and may be important for setting aspects of HPA axis tone, without impacting upon urinary steroid metabolite profile. These discordant data have significant implications for the use of these biomarkers of 11β-HSD1 activity in clinical studies. The paucity of metabolic abnormalities in LKO points to important compensatory effects by HPA

  9. Deletion of the Thyroid Hormone-Activating Type 2 Deiodinase Rescues Cone Photoreceptor Degeneration but Not Deafness in Mice Lacking Type 3 Deiodinase.

    Science.gov (United States)

    Ng, Lily; Liu, Hong; St Germain, Donald L; Hernandez, Arturo; Forrest, Douglas

    2017-06-01

    Type 2 deiodinase amplifies and type 3 deiodinase depletes levels of the active form of thyroid hormone, triiodothyronine. Given the opposing activities of these enzymes, we tested the hypothesis that they counteract each other's developmental functions by investigating whether deletion of type 2 deiodinase (encoded by Dio2) modifies sensory phenotypes in type 3 deiodinase-deficient (Dio3-/-) mice. Dio3-/- mice display degeneration of retinal cones, the photoreceptors that mediate daylight and color vision. In Dio2-/- mice, cone function was largely normal but deletion of Dio2 in Dio3-/- mice markedly recovered cone numbers and electroretinogram responses, suggesting counterbalancing roles for both enzymes in cone survival. Both Dio3-/- and Dio2-/- strains exhibit deafness with cochlear abnormalities. In Dio3-/-;Dio2-/- mice, deafness was exacerbated rather than alleviated, suggesting unevenly balanced actions by these enzymes during auditory development. Dio3-/- mice also exhibit an atrophic thyroid gland, low thyroxine, and high triiodothyronine levels, but this phenotype was ameliorated in Dio3-/-;Dio2-/- mice, indicating counterbalancing roles for the enzymes in determining the thyroid hormone status. The results suggest that the composite action of these two enzymes is a critical determinant in visual and auditory development and in setting the systemic thyroid hormone status.

  10. Anxiety- and depression-like behavior in mice lacking the CD157/BST1 gene, a risk factor for Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Olga eLopatina

    2014-04-01

    Full Text Available CD157, known as bone marrow stromal cell antigen-1, is a glycosylphosphatidylinositol-anchored ADP-ribosyl cyclase that supports the survival and function of B-lymphocytes and hematopoietic or intestinal stem cells. Although CD157/Bst1 is a risk locus in Parkinson’s disease (PD, little is known about the function of CD157 in the nervous system and contribution to PD progression. Here, we show that no apparent motor dysfunction was observed in young knockout (CD157-/- male mice under less aging-related effects on behaviors. CD157-/- mice exhibited anxiety-related and depression-like behaviors compared with wild-type mice. These behaviors were rescued through treatment with anti-psychiatric drugs and oxytocin. CD157 was weakly expressed in the amygdala and c-Fos immunoreactivity was less evident in CD157-/- mice than in wild-type mice. These results demonstrate for the first time that CD157 plays a role as a neuro-regulator and suggest a potential role in pre-motor symptoms in PD.

  11. Desacyl Ghrelin Decreases Anxiety-like Behavior in Male Mice.

    Science.gov (United States)

    Mahbod, Parinaz; Smith, Eric P; Fitzgerald, Maureen E; Morano, Rachel L; Packard, Benjamin A; Ghosal, Sriparna; Scheimann, Jessie R; Perez-Tilve, Diego; Herman, James P; Tong, Jenny

    2018-01-01

    Ghrelin is a 28-amino acid polypeptide that regulates feeding, glucose metabolism, and emotionality (stress, anxiety, and depression). Plasma ghrelin circulates as desacyl ghrelin (DAG) or, in an acylated form, acyl ghrelin (AG), through the actions of ghrelin O-acyltransferase (GOAT), exhibiting low or high affinity, respectively, for the growth hormone secretagogue receptor (GHSR) 1a. We investigated the role of endogenous AG, DAG, and GHSR1a signaling on anxiety and stress responses using ghrelin knockout (Ghr KO), GOAT KO, and Ghsr stop-floxed (Ghsr null) mice. Behavioral and hormonal responses were tested in the elevated plus maze and light/dark (LD) box. Mice lacking both AG and DAG (Ghr KO) increased anxiety-like behaviors across tests, whereas anxiety reactions were attenuated in DAG-treated Ghr KO mice and in mice lacking AG (GOAT KO). Notably, loss of GHSR1a (Ghsr null) did not affect anxiety-like behavior in any test. Administration of AG and DAG to Ghr KO mice with lifelong ghrelin deficiency reduced anxiety-like behavior and decreased phospho-extracellular signal-regulated kinase phosphorylation in the Edinger-Westphal nucleus in wild-type mice, a site normally expressing GHSR1a and involved in stress- and anxiety-related behavior. Collectively, our data demonstrate distinct roles for endogenous AG and DAG in regulation of anxiety responses and suggest that the behavioral impact of ghrelin may be context dependent. Copyright © 2018 Endocrine Society.

  12. Lack of Proinflammatory Cytokine Interleukin-6 or Tumor Necrosis Factor Receptor-1 Results in a Failure of the Innate Immune Response after Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    Lea-Jessica Albrecht

    2016-01-01

    Full Text Available The most frequent pathogen that causes bacterial meningitis is the Gram-positive bacterium Streptococcus pneumoniae. By entering the brain, host cells will be activated and proinflammatory cytokines like interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α are released. The goal of the current study was to examine the interaction between IL-6 and TNFR1 as receptor for TNF-α and the innate immune response in vivo in a model of Streptococcus pneumoniae-induced meningitis. For the experiments IL-6−/−, TNFR1−/−, and TNFR1-IL-6−/− KO mice were used. Our results revealed higher mortality rates and bacterial burden after infection in TNFR1−/−, IL-6−/−, and TNFR1-IL-6−/− mice and a decreased immune response including lower neutrophil infiltration in the meninges of TNFR1−/− and TNFR1-IL-6−/− mice in contrast to IL-6−/− and wild type mice. Furthermore, the increased mortality of TNFR1−/− and TNFR1-IL-6−/− mice correlated with decreased glial cell activation compared to IL-6−/− or wild type mice after pneumococcal meningitis. Altogether, the results show the importance of TNFR1 and IL-6 in the regulation of the innate immune response. The lack of TNFR1 and IL-6 results in higher mortality by weakened immune defence, whereas the lack of TNFR1 results in more severe impairment of the innate immune response than the lack of IL-6 alone.

  13. Lack of TNF-alpha receptor type 2 protects motor neurons in a cellular model of amyotrophic lateral sclerosis and in mutant SOD1 mice but does not affect disease progression.

    Science.gov (United States)

    Tortarolo, Massimo; Vallarola, Antonio; Lidonnici, Dario; Battaglia, Elisa; Gensano, Francesco; Spaltro, Gabriella; Fiordaliso, Fabio; Corbelli, Alessandro; Garetto, Stefano; Martini, Elisa; Pasetto, Laura; Kallikourdis, Marinos; Bonetto, Valentina; Bendotti, Caterina

    2015-10-01

    Changes in the homeostasis of tumor necrosis factor α (TNFα) have been demonstrated in patients and experimental models of amyotrophic lateral sclerosis (ALS). However, the contribution of TNFα to the development of ALS is still debated. TNFα is expressed by glia and neurons and acts through the membrane receptors TNFR1 and TNFR2, which may have opposite effects in neurodegeneration. We investigated the role of TNFα and its receptors in the selective motor neuron death in ALS in vitro and in vivo. TNFR2 expressed by astrocytes and neurons, but not TNFR1, was implicated in motor neuron loss in primary SOD1-G93A co-cultures. Deleting TNFR2 from SOD1-G93A mice, there was partial but significant protection of spinal motor neurons, sciatic nerves, and tibialis muscles. However, no improvement of motor impairment or survival was observed. Since the sciatic nerves of SOD1-G93A/TNFR2-/- mice showed high phospho-TAR DNA-binding protein 43 (TDP-43) accumulation and low levels of acetyl-tubulin, two indices of axonal dysfunction, the lack of symptom improvement in these mice might be due to impaired function of rescued motor neurons. These results indicate the interaction between TNFR2 and membrane-bound TNFα as an innovative pathway involved in motor neuron death. Nevertheless, its inhibition is not sufficient to stop disease progression in ALS mice, underlining the complexity of this pathology. We show evidence of the involvement of neuronal and astroglial TNFR2 in the motor neuron degeneration in ALS. Both concur to cause motor neuron death in primary astrocyte/spinal neuron co-cultures. TNFR2 deletion partially protects motor neurons and sciatic nerves in SOD1-G93A mice but does not improve their symptoms and survival. However, TNFR2 could be a new target for multi-intervention therapies. © 2015 International Society for Neurochemistry.

  14. Gene expression profiling of gastric mucosa in mice lacking CCK and gastrin receptors

    DEFF Research Database (Denmark)

    Zhao, Chun-Mei; Kodama, Yosuke; Flatberg, Arnar

    2014-01-01

    normalized, which was associated with an up-regulated pituitary adenylate cyclase-activating polypeptide (PACAP) type 1 receptor (PAC1). The basal part of the gastric mucosa expressed parathyroid hormone-like hormone (PTHLH) in a subpopulation of likely ECL cells (and possibly other cells) and vitamin D3 1α...... suggest a possible link between gastric PTHLH and vitamin D and bone metabolism.......The stomach produces acid, which may play an important role in the regulation of bone homeostasis. The aim of this study was to reveal signaling pathways in the gastric mucosa that involve the acid secretion and possibly the bone metabolism in CCK1 and/or CCK2 receptor knockout (KO) mice. Gastric...

  15. Aerosols transmit prions to immunocompetent and immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Johannes Haybaeck

    Full Text Available Prions, the agents causing transmissible spongiform encephalopathies, colonize the brain of hosts after oral, parenteral, intralingual, or even transdermal uptake. However, prions are not generally considered to be airborne. Here we report that inbred and crossbred wild-type mice, as well as tga20 transgenic mice overexpressing PrP(C, efficiently develop scrapie upon exposure to aerosolized prions. NSE-PrP transgenic mice, which express PrP(C selectively in neurons, were also susceptible to airborne prions. Aerogenic infection occurred also in mice lacking B- and T-lymphocytes, NK-cells, follicular dendritic cells or complement components. Brains of diseased mice contained PrP(Sc and transmitted scrapie when inoculated into further mice. We conclude that aerogenic exposure to prions is very efficacious and can lead to direct invasion of neural pathways without an obligatory replicative phase in lymphoid organs. This previously unappreciated risk for airborne prion transmission may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories.

  16. Pancreatic ductal adenocarcinoma mice lacking mucin 1 have a profound defect in tumor growth and metastasis.

    Science.gov (United States)

    Besmer, Dahlia M; Curry, Jennifer M; Roy, Lopamudra D; Tinder, Teresa L; Sahraei, Mahnaz; Schettini, Jorge; Hwang, Sun-Il; Lee, Yong Y; Gendler, Sandra J; Mukherjee, Pinku

    2011-07-01

    MUC1 is overexpressed and aberrantly glycosylated in more than 60% of pancreatic ductal adenocarcinomas. The functional role of MUC1 in pancreatic cancer has yet to be fully elucidated due to a dearth of appropriate models. In this study, we have generated mouse models that spontaneously develop pancreatic ductal adenocarcinoma (KC), which are either Muc1-null (KCKO) or express human MUC1 (KCM). We show that KCKO mice have significantly slower tumor progression and rates of secondary metastasis, compared with both KC and KCM. Cell lines derived from KCKO tumors have significantly less tumorigenic capacity compared with cells from KCM tumors. Therefore, mice with KCKO tumors had a significant survival benefit compared with mice with KCM tumors. In vitro, KCKO cells have reduced proliferation and invasion and failed to respond to epidermal growth factor, platelet-derived growth factor, or matrix metalloproteinase 9. Further, significantly less KCKO cells entered the G(2)-M phase of the cell cycle compared with the KCM cells. Proteomics and Western blotting analysis revealed a complete loss of cdc-25c expression, phosphorylation of mitogen-activated protein kinase (MAPK), as well as a significant decrease in nestin and tubulin-α2 chain expression in KCKO cells. Treatment with a MEK1/2 inhibitor, U0126, abrogated the enhanced proliferation of the KCM cells but had minimal effect on KCKO cells, suggesting that MUC1 is necessary for MAPK activity and oncogenic signaling. This is the first study to utilize a Muc1-null PDA mouse to fully elucidate the oncogenic role of MUC1, both in vivo and in vitro. ©2011 AACR

  17. Selegiline Ameliorates Depression-Like Behavior in Mice Lacking the CD157/BST1 Gene, a Risk Factor for Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Satoka Kasai

    2017-05-01

    Full Text Available Parkinson’s disease (PD, a neurodegenerative disorder, is accompanied by various non-motor symptoms including depression and anxiety, which may precede the onset of motor symptoms. Selegiline is an irreversible monoamine oxidase-B (MAO-B inhibitor, and is widely used in the treatment of PD and major depression. However, there are few reports about the effects of selegiline on non-motor symptoms in PD. The aim of this study was to explore the antidepressant and anxiolytic effects of selegiline, using CD157/BST1 knockout (CD157 KO mouse, a PD-related genetic model displaying depression and anxiety, compared with other antiparkinsonian drugs and an antidepressant, and was to investigate the effects of selegiline on biochemical parameters in emotion-related brain regions. A single administration of selegiline (1–10 mg/kg dose-dependently reduced immobility time in the forced swimming test (FST in CD157 KO mice, but not C57BL/6N wild-type (WT mice. At 10 mg/kg, but not 3 mg/kg, selegiline significantly increased climbing time in CD157 KO mice. A single administration of the antiparkinsonian drugs pramipexole (a dopamine (DA D2/D3 receptor agonist or rasagiline (another MAO-B inhibitor, and repeated injections of a noradrenergic and specific serotonergic antidepressant (NaSSA, mirtazapine, also decreased immobility time, but did not increase climbing time, in CD157 KO mice. The antidepressant-like effects of 10 mg/kg selegiline were comparable to those of 10 mg/kg rasagiline, and tended to be stronger than those of 1 mg/kg rasagiline. After the FST, CD157 KO mice showed decreases in striatal and hippocampal serotonin (5-HT content, cortical norepinephrine (NE content, and plasma corticosterone concentration. A single administration of selegiline at 10 mg/kg returned striatal 5-HT, cortical NE, and plasma corticosterone levels to those observed in WT mice. In the open field test (OFT, repeated administration of mirtazapine had anxiolytic effects

  18. IL-4 deficiency is associated with mechanical hypersensitivity in mice.

    Directory of Open Access Journals (Sweden)

    Nurcan Üçeyler

    Full Text Available Interleukin-4 (IL-4 is an anti-inflammatory and analgesic cytokine that induces opioid receptor transcription. We investigated IL-4 knockout (ko mice to characterize their pain behavior before and after chronic constriction injury (CCI of the sciatic nerve as a model for neuropathic pain. We investigated opioid responsivity and measured cytokine and opioid receptor gene expression in the peripheral and central nervous system (PNS, CNS of IL-4 ko mice in comparison with wildtype (wt mice. Naïve IL-4 ko mice displayed tactile allodynia (wt: 0.45 g; ko: 0.18 g; p<0.001, while responses to heat and cold stimuli and to muscle pressure were not different. No compensatory changes in the gene expression of tumor necrosis factor-alpha (TNF, IL-1β, IL-10, and IL-13 were found in the PNS and CNS of naïve IL-4 ko mice. However, IL-1β gene expression was stronger in the sciatic nerve of IL-4 ko mice (p<0.001 28 days after CCI and only IL-4 ko mice had elevated IL-10 gene expression (p = 0.014. Remarkably, CCI induced TNF (p<0.01, IL-1β (p<0.05, IL-10 (p<0.05, and IL-13 (p<0.001 gene expression exclusively in the ipsilateral spinal cord of IL-4 ko mice. The compensatory overexpression of the anti-inflammatory and analgesic cytokines IL-10 and IL-13 in the spinal cord of IL-4 ko mice may explain the lack of genotype differences for pain behavior after CCI. Additionally, CCI induced gene expression of μ, κ, and δ opioid receptors in the contralateral cortex and thalamus of IL-4 ko mice, paralleled by fast onset of morphine analgesia, but not in wt mice. We conclude that a lack of IL-4 leads to mechanical sensitivity; the compensatory hyperexpression of analgesic cytokines and opioid receptors after CCI, in turn, protects IL-4 ko mice from enhanced pain behavior after nerve lesion.

  19. Acute Systemic Infection with Dengue Virus Leads to Vascular Leakage and Death through Tumor Necrosis Factor-α and Tie2/Angiopoietin Signaling in Mice Lacking Type I and II Interferon Receptors.

    Science.gov (United States)

    Phanthanawiboon, Supranee; Limkittikul, Kriengsak; Sakai, Yusuke; Takakura, Nobuyuki; Saijo, Masayuki; Kurosu, Takeshi

    2016-01-01

    Severe dengue is caused by host responses to viral infection, but the pathogenesis remains unknown. This is, in part, due to the lack of suitable animal models. Here, we report a non-mouse-adapted low-passage DENV-3 clinical isolate, DV3P12/08, derived from recently infected patients. DV3P12/08 caused a lethal systemic infection in type I and II IFN receptor KO mice (IFN-α/β/γR KO mice), which have the C57/BL6 background. Infection with DV3P12/08 induced a cytokine storm, resulting in severe vascular leakage (mainly in the liver, kidney and intestine) and organ damage, leading to extensive hemorrhage and rapid death. DV3P12/08 infection triggered the release of large amounts of TNF-α, IL-6, and MCP-1. Treatment with a neutralizing anti-TNF-α antibody (Ab) extended survival and reduced liver damage without affecting virus production. Anti-IL-6 neutralizing Ab partly prolonged mouse survival. The anti-TNF-α Ab suppressed IL-6, MCP-1, and IFN-γ levels, suggesting that the severe response to infection was triggered by TNF-α. High levels of TNF-α mRNA were expressed in the liver and kidneys, but not in the small intestine, of infected mice. Conversely, high levels of IL-6 mRNA were expressed in the intestine. Importantly, treatment with Angiopoietin-1, which is known to stabilize blood vessels, prolonged the survival of DV3P12/08-infected mice. Taken together, the results suggest that an increased level of TNF-α together with concomitant upregulation of Tie2/Angiopoietin signaling have critical roles in severe dengue infection.

  20. Multiple alterations of platelet functions dominated by increased secretion in mice lacking Cdc42 in platelets

    DEFF Research Database (Denmark)

    Pleines, Irina; Eckly, Anita; Elvers, Margitta

    2010-01-01

    formation and exocytosis in various cell types, but its exact function in platelets is not established. Here, we show that the megakaryocyte/platelet-specific loss of Cdc42 leads to mild thrombocytopenia and a small increase in platelet size in mice. Unexpectedly, Cdc42-deficient platelets were able to form...

  1. Facilitated stimulus-response associative learning and long-term memory in mice lacking the NTAN1 amidase of the N-end rule pathway.

    Science.gov (United States)

    Balogh, S A; McDowell, C S; Tae Kwon, Y; Denenberg, V H

    2001-02-23

    The N-end rule relates the in vivo half-life of a protein to the identity of its N-terminal residue. Inactivation of the NTAN1 gene encoding the asparagine-specific N-terminal amidase in mice results in impaired spatial memory [26]. The studies described here were designed to further characterize the effects upon learning and memory of inactivating the NTAN1 gene. NTAN1-deficient mice were found to be better than wild-type mice on black-white and horizontal-vertical discrimination learning. They were also better at 8-week Morris maze retention testing when a reversal trial was not included in the testing procedures. In all three tasks NTAN1-deficient mice appeared to use a strong win-stay strategy. It is concluded that inactivating the asparagine-specific branch of the N-end rule pathway in mice results in impaired spatial learning with concomitant compensatory restructuring of the nervous system in favor of non-spatial (stimulus-response) learning.

  2. Lack of centrioles and primary cilia in STIL(-/-) mouse embryos.

    Science.gov (United States)

    David, Ahuvit; Liu, Fengying; Tibelius, Alexandra; Vulprecht, Julia; Wald, Diana; Rothermel, Ulrike; Ohana, Reut; Seitel, Alexander; Metzger, Jasmin; Ashery-Padan, Ruth; Meinzer, Hans-Peter; Gröne, Hermann-Josef; Izraeli, Shai; Krämer, Alwin

    2014-01-01

    Although most animal cells contain centrosomes, consisting of a pair of centrioles, their precise contribution to cell division and embryonic development is unclear. Genetic ablation of STIL, an essential component of the centriole replication machinery in mammalian cells, causes embryonic lethality in mice around mid gestation associated with defective Hedgehog signaling. Here, we describe, by focused ion beam scanning electron microscopy, that STIL(-/-) mouse embryos do not contain centrioles or primary cilia, suggesting that these organelles are not essential for mammalian development until mid gestation. We further show that the lack of primary cilia explains the absence of Hedgehog signaling in STIL(-/-) cells. Exogenous re-expression of STIL or STIL microcephaly mutants compatible with human survival, induced non-templated, de novo generation of centrioles in STIL(-/-) cells. Thus, while the abscence of centrioles is compatible with mammalian gastrulation, lack of centrioles and primary cilia impairs Hedgehog signaling and further embryonic development.

  3. Burn injury reveals altered phenotype in mannan-binding lectin-deficient mice

    DEFF Research Database (Denmark)

    Møller-Kristensen, Mette; Hamblin, Michael R; Thiel, Steffen

    2007-01-01

    Burn injury destroys skin, the second largest innate immune organ in the body, and triggers chaotic immune and inflammatory responses. The pattern recognition molecule, mannan-binding lectin (MBL), plays an important role in the first-line host defense against infectious agents. MBL initiates...... the lectin complement pathway and acts as an opsonin. Recent studies suggest that MBL also modulates inflammatory responses. We report that local responses after burn in MBL null mice differ from those found in wild-type (WT) mice in the following important biological markers: spontaneous eschar separation......, thinned epidermis and dermis, upregulation of soluble factors including cytokines, chemokines, cell adhesion molecules, a growth factor-binding protein, and matrix metalloproteinases. Mice lacking C1q, C4, or C3 did not show the lack of eschar separation seen in MBL null-burn phenotype. These findings...

  4. Enhanced leptin sensitivity and improved glucose homeostasis in mice lacking suppressor of cytokine signaling-3 in POMC-expressing cells.

    Science.gov (United States)

    Kievit, Paul; Howard, Jane K; Badman, Michael K; Balthasar, Nina; Coppari, Roberto; Mori, Hiroyuki; Lee, Charlotte E; Elmquist, Joel K; Yoshimura, Akihiko; Flier, Jeffrey S

    2006-08-01

    Suppressor of cytokine signaling-3 (Socs-3) negatively regulates the action of various cytokines, as well as the metabolic hormones leptin and insulin. Mice with haploinsufficiency of Socs-3, or those with neuronal deletion of Socs-3, are lean and more leptin and insulin sensitive. To examine the role of Socs-3 within specific neurons critical to energy balance, we created mice with selective deletion of Socs-3 within pro-opiomelanocortin (POMC)-expressing cells. These mice had enhanced leptin sensitivity, measured by weight loss and food intake after leptin infusion. On chow diet, glucose homeostasis was improved despite normal weight gain. On a high-fat diet, the rate of weight gain was reduced, due to increased energy expenditure rather than decreased food intake; glucose homeostasis and insulin sensitivity were substantially improved. These studies demonstrate that Socs-3 within POMC neurons regulates leptin sensitivity and glucose homeostasis, and plays a key role in linking high-fat diet to disordered metabolism.

  5. Does Skeletal Muscle Mass Influence Breast Cancer? Evaluating Mammary Tumorigenesis and Progression Genetically Hyper-Muscular Mice

    National Research Council Canada - National Science Library

    Zimmers, Teresa

    2006-01-01

    .... Mice lacking the skeletal muscle-specific muscle growth inhibitor myostatin and mice expressing a dominant negative form of the myostatin receptor, Activin Receptor Type IIB, display heightened muscle mass...

  6. Interferon-lambda contributes to innate immunity of mice against influenza A virus but not against hepatotropic viruses

    DEFF Research Database (Denmark)

    Mordstein, M; Kochs, G; Dumoutier, L

    2008-01-01

    Virus-infected cells secrete a broad range of interferon (IFN) subtypes which in turn trigger the synthesis of antiviral factors that confer host resistance. IFN-alpha, IFN-beta and other type I IFNs signal through a common universally expressed cell surface receptor, whereas IFN-lambda uses....... Mice lacking functional IFN-lambda receptors were only slightly more susceptible to influenza virus than wild-type mice. However, mice lacking functional receptors for both IFN-alpha/beta and IFN-lambda were hypersensitive and even failed to restrict usually non-pathogenic influenza virus mutants...

  7. Perception of sweet taste is important for voluntary alcohol consumption in mice.

    Science.gov (United States)

    Blednov, Y A; Walker, D; Martinez, M; Levine, M; Damak, S; Margolskee, R F

    2008-02-01

    To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: alpha-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solutions than did wild-type littermates. In contrast, avoidance of quinine solutions was less in Gnat3 or Trpm5 knockout mice than in wild-type mice, whereas Tas1r3 null mice were not different from wild type in their response to quinine solutions. There were no differences in null vs. wild-type mice in their consumption of sodium chloride solutions. To determine the cause for reduction of ethanol intake, we studied other ethanol-induced behaviors known to be related to alcohol consumption. There were no differences between null and wild-type mice in ethanol-induced loss of righting reflex, severity of acute ethanol withdrawal or conditioned place preference for ethanol. Weaker conditioned taste aversion (CTA) to alcohol in null mice may have been caused by weaker rewarding value of the conditioned stimulus (saccharin). When saccharin was replaced by sodium chloride, no differences in CTA to alcohol between knockout and wild-type mice were seen. Thus, deletion of any one of three different genes involved in detection of sweet taste leads to a substantial reduction of alcohol intake without any changes in pharmacological actions of ethanol.

  8. A mouse model of DEPDC5-related epilepsy: Neuronal loss of Depdc5 causes dysplastic and ectopic neurons, increased mTOR signaling, and seizure susceptibility.

    Science.gov (United States)

    Yuskaitis, Christopher J; Jones, Brandon M; Wolfson, Rachel L; Super, Chloe E; Dhamne, Sameer C; Rotenberg, Alexander; Sabatini, David M; Sahin, Mustafa; Poduri, Annapurna

    2018-03-01

    DEPDC5 is a newly identified epilepsy-related gene implicated in focal epilepsy, brain malformations, and Sudden Unexplained Death in Epilepsy (SUDEP). In vitro, DEPDC5 negatively regulates amino acid sensing by the mTOR complex 1 (mTORC1) pathway, but the role of DEPDC5 in neurodevelopment and epilepsy has not been described. No animal model of DEPDC5-related epilepsy has recapitulated the neurological phenotypes seen in patients, and germline knockout rodent models are embryonic lethal. Here, we establish a neuron-specific Depdc5 conditional knockout mouse by cre-recombination under the Synapsin1 promotor. Depdc5 flox/flox -Syn1 Cre (Depdc5cc+) mice survive to adulthood with a progressive neurologic phenotype that includes motor abnormalities (i.e., hind limb clasping) and reduced survival compared to littermate control mice. Depdc5cc+ mice have larger brains with increased cortical neuron size and dysplastic neurons throughout the cortex, comparable to the abnormal neurons seen in human focal cortical dysplasia specimens. Depdc5 results in constitutive mTORC1 hyperactivation exclusively in neurons as measured by the increased phosphorylation of the downstream ribosomal protein S6. Despite a lack of increased mTORC1 signaling within astrocytes, Depdc5cc+ brains show reactive astrogliosis. We observed two Depdc5cc+ mice to have spontaneous seizures, including a terminal seizure. We demonstrate that as a group Depdc5cc+ mice have lowered seizure thresholds, as evidenced by decreased latency to seizures after chemoconvulsant injection and increased mortality from pentylenetetrazole-induced seizures. In summary, our neuron-specific Depdc5 knockout mouse model recapitulates clinical, pathological, and biochemical features of human DEPDC5-related epilepsy and brain malformations. We thereby present an important model in which to study targeted therapeutic strategies for DEPDC5-related conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Lack of effect on the chromosomal non-disjunction in aged female mice after low dose x-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Strausmanis, R; Hendrikson, I B; Holmberg, M; Roennbaeck, C [Research Inst. of National Defence, Sundbyberg (Sweden). Dept. 4

    1978-02-01

    Karyotypes were determined in 1064 embryos of aged C57/BL mothers. The virgin female mice were irradiated with 0, 4, 8 or 16 R of X-rays, respectively, and placed with young untreated males 5 days after irradiation. 10.5-days old embryos were recovered from the uterus. Aneuploid embryos classified as alive (heart beats observed at the dissection) were 1 monosomic in the control group (496 embryos) and 2 trisomics in the irradiated group (568 embryos). The number of aneuploid embryos classified as dead was 4 trisomic cases in the control group and 3 trisomics in the irradiated group. The data indicate that trisomic embryos are not uncommon in the mouse but are eliminated in post-implantation death. In contrast to the results of Yamamoto et al. the present data do not demonstrate an increased frequency of chromosome abnormalities in embryos of aged mice X-irradiated before mating as compared to non-irradiated ones.

  10. Lack of effect on the chromosomal non-disjunction in aged female mice after low dose x-irradiation

    International Nuclear Information System (INIS)

    Strausmanis, R.; Hendrikson, I.-B.; Holmberg, M.; Roennbaeck, C.

    1978-01-01

    Karyotypes were determined in 1064 embryos of aged C57/BL mothers. The virgin female mice were irradiated with 0, 4, 8 or 16 R of X-rays, respectively, and placed with young untreated males 5 days after irradiation. 10.5-days old embryos were recovered from the uterus. Aneuploid embryos classified as alive (heart beats observed at the dissection) were 1 monosomic in the control group (496 embryos) and 2 trisomics in the irradiated group (568 embryos). The number of aneuploid embryos classified as dead was 4 trisomic cases in the control group and 3 trisomics in the irradiated group. The data indicate that trisomic embryos are not uncommon in the mouse but are eliminated in post-implantation death. In contrast to the results of Yamamoto et al. the present data do not demonstrate an increased frequency of chromosome abnormalities in embryos of aged mice X-irradiated before mating as compared to non-irradiated ones

  11. Lack of Plasma Protein Hemopexin Results in Increased Duodenal Iron Uptake.

    Science.gov (United States)

    Fiorito, Veronica; Geninatti Crich, Simonetta; Silengo, Lorenzo; Aime, Silvio; Altruda, Fiorella; Tolosano, Emanuela

    2013-01-01

    The body concentration of iron is regulated by a fine equilibrium between absorption and losses of iron. Iron can be absorbed from diet as inorganic iron or as heme. Hemopexin is an acute phase protein that limits iron access to microorganisms. Moreover, it is the plasma protein with the highest binding affinity for heme and thus it mediates heme-iron recycling. Considering its involvement in iron homeostasis, it was postulated that hemopexin may play a role in the physiological absorption of inorganic iron. Hemopexin-null mice showed elevated iron deposits in enterocytes, associated with higher duodenal H-Ferritin levels and a significant increase in duodenal expression and activity of heme oxygenase. The expression of heme-iron and inorganic iron transporters was normal. The rate of iron absorption was assessed by measuring the amount of (57)Fe retained in tissues from hemopexin-null and wild-type animals after administration of an oral dose of (57)FeSO4 or of (57)Fe-labelled heme. Higher iron retention in the duodenum of hemopexin-null mice was observed as compared with normal mice. Conversely, iron transfer from enterocytes to liver and bone marrow was unaffected in hemopexin-null mice. The increased iron level in hemopexin-null duodenum can be accounted for by an increased iron uptake by enterocytes and storage in ferritins. These data indicate that the lack of hemopexin under physiological conditions leads to an enhanced duodenal iron uptake thus providing new insights to our understanding of body iron homeostasis.

  12. Pancreatic Ductal Adenocarcinoma (PDA) mice lacking Mucin 1 have a profound defect in tumor growth and metastasis

    Science.gov (United States)

    Besmer, Dahlia M.; Curry, Jennifer M.; Roy, Lopamudra D.; Tinder, Teresa L.; Sahraei, Mahnaz; Schettini, Jorge; Hwang, Sun-Il; Lee, Yong Y.; Gendler, Sandra J.; Mukherjee, Pinku

    2011-01-01

    MUC1 is over expressed and aberrantly glycosolated in >60% of pancreatic ductal adenocarcinomas. The functional role of MUC1 in pancreatic cancer has yet to be fully elucidated due to a dearth of appropriate models. In the present study, we have generated mouse models that spontaneously develop pancreatic ductal adenocarcinoma (KC), which are either Muc1-null (KCKO) or express human MUC1 (KCM). We show that KCKO mice have significantly slower tumor progression and rates of secondary metastasis, compared to both KC and KCM. Cell lines derived from KCKO tumors have significantly lower tumorigenic capacity compared to cells from KCM tumors. Therefore, mice with KCKO tumors had a significant survival benefit compared to mice with KCM tumors. In vitro, KCKO cells have reduced proliferation and invasion and failed to respond to epidermal growth factor (EGF), platelet-derived growth factor (PDGF), or matrix metalloproteinase-9 (MMP9). Further, significantly fewer KCKO cells entered the G2M phase of the cell cycle compared to the KCM cells. Proteomics and western blotting analysis revealed a complete loss of cdc-25c expression, phosphorylation of MAPK, as well as a significant decrease in Nestin and Tubulin α-2 chain expression in KCKO cells. Treatment with a MEK1/2 inhibitor, U0126, abrogated the enhanced proliferation of the KCM cells but had minimal effect on KCKO cells, suggesting that MUC1 is necessary for MAPK activity and oncogenic signaling. This is the first study to utilize a Muc1-null PDA mouse in order to fully elucidate the oncogenic role of MUC1, both in vivo and in vitro. PMID:21558393

  13. B-1a transitional cells are phenotypically distinct and are lacking in mice deficient in IκBNS

    Science.gov (United States)

    Pedersen, Gabriel K.; Àdori, Monika; Khoenkhoen, Sharesta; Dosenovic, Pia; Beutler, Bruce; Karlsson Hedestam, Gunilla B.

    2014-01-01

    B-1 cells mediate early protection against infection by responding to T cell-independent (TI) antigens found on the surface of various pathogens. Mice with impaired expression of the atypical IκB protein IκBNS have markedly reduced frequencies of B-1 cells. We used a mouse strain with dysfunctional IκBNS derived from an N-ethyl-N-nitrosourea (ENU) screen, named bumble, to investigate the point in the development of B-1 cells where IκBNS is required. The presence of wild-type (wt) peritoneal cells in mixed wt/bumble chimeras did not rescue the development of bumble B-1 cells, but wt peritoneal cells transferred to bumble mice restored natural IgM levels and response to TI antigens. The bumble and wt mice displayed similar levels of fetal liver B-1 progenitors and splenic neonatal transitional B (TrB) cells, both of which were previously shown to give rise to B-1 cells. Interestingly, we found that a subset of wt neonatal TrB cells expressed common B-1a markers (TrB-1a) and that this cell population was absent in the bumble neonatal spleen. Sorted TrB-1a (CD93+IgM+CD5+) cells exclusively generated B-1a cells when adoptively transferred, whereas sorted CD93+IgM+CD5− cells gave rise to B-2 cells and, to a lesser extent, B-1b and B-1a cells. This study identifies a phenotypically distinct splenic population of TrB-1a cells and establishes that the development of B-1a cells is blocked before this stage in the absence of IκBNS. PMID:25228759

  14. Action potential generation in the small intestine of W mutant mice that lack interstitial cells of Cajal

    DEFF Research Database (Denmark)

    Malysz, J; Thuneberg, L; Mikkelsen, Hanne Birte

    1996-01-01

    significantly changed. Neither FLC nor MLC were part of a network nor did they form specialized junctions with neighboring cells as ICC do. Hence no cell type had replaced ICC at their normal morphological position associated with Auerbach's plexus. ICC were present in W/Wv mice at the deep muscular plexus...

  15. Hispidulin inhibits the release of glutamate in rat cerebrocortical nerve terminals

    International Nuclear Information System (INIS)

    Lin, Tzu-Yu; Lu, Cheng-Wei; Wang, Chia-Chuan; Lu, Jyh-Feng; Wang, Su-Jane

    2012-01-01

    Hispidulin, a naturally occurring flavone, has been reported to have an antiepileptic profile. An excessive release of glutamate is considered to be related to neuropathology of epilepsy. We investigated whether hispidulin affected endogenous glutamate release in rat cerebral cortex nerve terminals (synaptosomes) and explored the possible mechanism. Hispidulin inhibited the release of glutamate evoked by the K + channel blocker 4-aminopyridine (4-AP). The effects of hispidulin on the evoked glutamate release were prevented by the chelation of extracellular Ca 2+ ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate did not have any effect on hispidulin action. Hispidulin reduced the depolarization-induced increase in cytosolic free Ca 2+ concentration ([Ca 2+ ] C ), but did not alter 4-AP-mediated depolarization. Furthermore, the effect of hispidulin on evoked glutamate release was abolished by blocking the Ca v 2.2 (N-type) and Ca v 2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na + /Ca 2+ exchange. Mitogen-activated protein kinase kinase (MEK) inhibition also prevented the inhibitory effect of hispidulin on evoked glutamate release. Western blot analyses showed that hispidulin decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and synaptic vesicle-associated protein synapsin I, a major presynaptic substrate for ERK; this decrease was also blocked by the MEK inhibitor. Moreover, the inhibition of glutamate release by hispidulin was strongly attenuated in mice without synapsin I. These results show that hispidulin inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca 2+ entry and ERK/synapsin I signaling pathway. -- Highlights: ► Hispidulin inhibited glutamate release from rat cerebrocortical synaptosomes. ► This action did

  16. Hispidulin inhibits the release of glutamate in rat cerebrocortical nerve terminals

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Tzu-Yu [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei, 22060, Taiwan (China); Department of Mechanical Engineering, Yuan Ze University, Taoyuan, 320, Taiwan (China); Lu, Cheng-Wei [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei, 22060, Taiwan (China); Wang, Chia-Chuan; Lu, Jyh-Feng [School of Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China); Wang, Su-Jane, E-mail: med0003@mail.fju.edu.tw [Graduate Institute of Basic Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China); School of Medicine, Fu Jen Catholic University, No.510, Zhongzheng Rd., Xinzhuang Dist., New Taipei, 24205, Taiwan (China)

    2012-09-01

    Hispidulin, a naturally occurring flavone, has been reported to have an antiepileptic profile. An excessive release of glutamate is considered to be related to neuropathology of epilepsy. We investigated whether hispidulin affected endogenous glutamate release in rat cerebral cortex nerve terminals (synaptosomes) and explored the possible mechanism. Hispidulin inhibited the release of glutamate evoked by the K{sup +} channel blocker 4-aminopyridine (4-AP). The effects of hispidulin on the evoked glutamate release were prevented by the chelation of extracellular Ca{sup 2+} ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate did not have any effect on hispidulin action. Hispidulin reduced the depolarization-induced increase in cytosolic free Ca{sup 2+} concentration ([Ca{sup 2+}]{sub C}), but did not alter 4-AP-mediated depolarization. Furthermore, the effect of hispidulin on evoked glutamate release was abolished by blocking the Ca{sub v}2.2 (N-type) and Ca{sub v}2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na{sup +}/Ca{sup 2+} exchange. Mitogen-activated protein kinase kinase (MEK) inhibition also prevented the inhibitory effect of hispidulin on evoked glutamate release. Western blot analyses showed that hispidulin decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and synaptic vesicle-associated protein synapsin I, a major presynaptic substrate for ERK; this decrease was also blocked by the MEK inhibitor. Moreover, the inhibition of glutamate release by hispidulin was strongly attenuated in mice without synapsin I. These results show that hispidulin inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca{sup 2+} entry and ERK/synapsin I signaling pathway. -- Highlights: ► Hispidulin inhibited glutamate release from rat

  17. Ciproxifan, a histamine H{sub 3} receptor antagonist and inverse agonist, presynaptically inhibits glutamate release in rat hippocampus

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cheng-Wei; Lin, Tzu-Yu [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei City 22060, Taiwan (China); Department of Mechanical Engineering, Yuan Ze University, Taoyuan 320, Taiwan (China); Chang, Chia-Ying [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei City 22060, Taiwan (China); Department of Chemistry, Fu Jen Catholic University, No. 510, Chung-Cheng Road, Hsin-Chuang District, New Taipei City 24205, Taiwan (China); Huang, Shu-Kuei [Department of Anesthesiology, Far-Eastern Memorial Hospital, Pan-Chiao District, New Taipei City 22060, Taiwan (China); Wang, Su-Jane, E-mail: med0003@mail.fju.edu.tw [School of Medicine, Fu Jen Catholic University, No. 510, Chung-Cheng Rd., Hsin-Chuang, New Taipei 24205, Taiwan (China); Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan City, Taiwan (China)

    2017-03-15

    Ciproxifan is an H{sub 3} receptor antagonist and inverse agonist with antipsychotic effects in several preclinical models; its effect on glutamate release has been investigated in the rat hippocampus. In a synaptosomal preparation, ciproxifan reduced 4-aminopyridine (4-AP)-evoked Ca{sup 2+}-dependent glutamate release and cytosolic Ca{sup 2+} concentration elevation but did not affect the membrane potential. The inhibitory effect of ciproxifan on 4-AP-evoked glutamate release was prevented by the Gi/Go-protein inhibitor pertussis toxin and Ca{sub v}2.2 (N-type) and Ca{sub v}2.1 (P/Q-type) channel blocker ω-conotoxin MVIIC, but was not affected by the intracellular Ca{sup 2+}-release inhibitors dantrolene and CGP37157. Furthermore, the phospholipase A{sub 2} (PLA{sub 2}) inhibitor OBAA, prostaglandin E{sub 2} (PGE{sub 2}), PGE2 subtype 2 (EP{sub 2}) receptor antagonist PF04418948, and extracellular signal-regulated kinase (ERK) inhibitor FR180204 eliminated the inhibitory effect of ciproxifan on glutamate release. Ciproxifan reduced the 4-AP-evoked phosphorylation of ERK and synapsin I, a presynaptic target of ERK. The ciproxifan-mediated inhibition of glutamate release was prevented in synaptosomes from synapsin I-deficient mice. Moreover, ciproxifan reduced the frequency of miniature excitatory postsynaptic currents without affecting their amplitude in hippocampal slices. Our data suggest that ciproxifan, acting through the blockade of Gi/Go protein-coupled H{sub 3} receptors present on hippocampal nerve terminals, reduces voltage-dependent Ca{sup 2+} entry by diminishing PLA{sub 2}/PGE{sub 2}/EP{sub 2} receptor pathway, which subsequently suppresses the ERK/synapsin I cascade to decrease the evoked glutamate release. - Highlights: • Ciproxifan presynaptically reduces glutamate release in the hippocampus in vitro. • Decrease in voltage-dependent Ca{sup 2+} influx is involved. • A role for the PLA{sub 2}/PGE{sub 2}/EP{sub 2} pathway in the action of

  18. Enzyme replacement prevents enamel defects in hypophosphatasia mice

    Science.gov (United States)

    Yadav, Manisha C.; de Oliveira, Rodrigo Cardoso; Foster, Brian L.; Fong, Hanson; Cory, Esther; Narisawa, Sonoko; Sah, Robert L.; Somerman, Martha; Whyte, Michael P.; Millán, José Luis

    2012-01-01

    Hypophosphatasia (HPP) is the inborn error of metabolism characterized by deficiency of alkaline phosphatase activity leading to rickets or osteomalacia and to dental defects. HPP occurs from loss-of-function mutations within the gene that encodes the tissue-nonspecific isozyme of alkaline phosphatase (TNAP). TNAP knockout (Alpl−/−, a.k.a. Akp2−/−) mice closely phenocopy infantile HPP, including the rickets, vitamin B6-responsive seizures, improper dentin mineralization, and lack of acellular cementum. Here, we report that lack of TNAP in Alpl−/− mice also causes severe enamel defects, which are preventable by enzyme replacement with mineral-targeted TNAP (ENB-0040). Immunohistochemistry was used to map the spatiotemporal expression of TNAP in the tissues of the developing enamel organ of healthy mouse molars and incisors. We found strong, stage-specific expression of TNAP in ameloblasts. In the Alpl−/− mice, histological, μCT, and scanning electron microscopy analysis showed reduced mineralization and disrupted organization of the rods and inter-rod structures in enamel of both the molars and incisors. All of these abnormalities were prevented in mice receiving from birth daily subcutaneous injections of mineral-targeting, human TNAP (sALP-FcD10, a.k.a. ENB-0040) at 8.2 mg/kg/day for up to 44 days. These data reveal an important role for TNAP in enamel mineralization, and demonstrate the efficacy of mineral-targeted TNAP to prevent enamel defects in HPP. PMID:22461224

  19. The Nanoscale Observation of the Three-Dimensional Structures of Neurosynapses, Membranous Conjunctions Between Cultured Hippocampal Neurons and Their Significance in the Development of Epilepsy.

    Science.gov (United States)

    Sun, Lan; Jiang, Shuang; Tang, Xianhua; Zhang, Yingge; Qin, Luye; Jiang, Xia; Yu, Albert Cheung Hoi

    2016-12-01

    The nanoscale three-dimensional structures of neurosynapses are unknown, and the neuroanatomical basis of epilepsy remains to be elucidated. Here, we studied the nanoscale three-dimensional synapses between hippocampal neurons, and membranous conjunctions between neurons were found with atomic force microscopy (AFM) and confirmed by transmission electron microscope (TEM), and their pathophysiological significance was primarily investigated. The neurons and dendrites were marked by MAP-2, axons by neurofilament 200, and synapses by synapsin I immunological staining. In the synapsin I-positive neurite ends of the neurons positively stained with MAP-2 and neurofilament 200, neurosynapses with various nanoscale morphology and structure could be found by AFM. The neurosynapses had typical three-dimensional structures of synaptic triplet including the presynaptic neurite end, synaptic cleft of 30 ∼ 40 in chemical synapses and 2 ∼ 6 nm in electrical ones, the postsynaptic neurite or dendrite spine, the typical neurite end button, the distinct pre- and postsynaptic membranes, and the obvious thickening of the postsynaptic membranes or neurites. Some membranous connections including membrane-like junctions (MLJ) and fiber-tube links (FTL) without triplet structures and cleft were found between neurons. The development frequencies of the two membranous conjunctions increased while those of the synaptic conjunctions decreased between the neurons from Otx1 knock-out mice in comparison with those between the neurons from normal mice. These results suggested that the neuroanatomical basis of Otx1 knock-out epilepsy is the combination of the decreased synaptic conjunctions and the increased membranous conjunctions.

  20. Mice Lacking the Alpha9 Subunit of the Nicotinic Acetylcholine Receptor Exhibit Deficits in Frequency Difference Limens and Sound Localization

    Directory of Open Access Journals (Sweden)

    Amanda Clause

    2017-06-01

    Full Text Available Sound processing in the cochlea is modulated by cholinergic efferent axons arising from medial olivocochlear neurons in the brainstem. These axons contact outer hair cells in the mature cochlea and inner hair cells during development and activate nicotinic acetylcholine receptors composed of α9 and α10 subunits. The α9 subunit is necessary for mediating the effects of acetylcholine on hair cells as genetic deletion of the α9 subunit results in functional cholinergic de-efferentation of the cochlea. Cholinergic modulation of spontaneous cochlear activity before hearing onset is important for the maturation of central auditory circuits. In α9KO mice, the developmental refinement of inhibitory afferents to the lateral superior olive is disturbed, resulting in decreased tonotopic organization of this sound localization nucleus. In this study, we used behavioral tests to investigate whether the circuit anomalies in α9KO mice correlate with sound localization or sound frequency processing. Using a conditioned lick suppression task to measure sound localization, we found that three out of four α9KO mice showed impaired minimum audible angles. Using a prepulse inhibition of the acoustic startle response paradigm, we found that the ability of α9KO mice to detect sound frequency changes was impaired, whereas their ability to detect sound intensity changes was not. These results demonstrate that cholinergic, nicotinic α9 subunit mediated transmission in the developing cochlear plays an important role in the maturation of hearing.

  1. Acute heat-evoked temperature sensation is impaired but not abolished in mice lacking TRPV1 and TRPV3 channels.

    Science.gov (United States)

    Marics, Irène; Malapert, Pascale; Reynders, Ana; Gaillard, Stéphane; Moqrich, Aziz

    2014-01-01

    The discovery of heat-sensitive Transient Receptor Potential Vanilloid ion channels (ThermoTRPVs) greatly advanced our molecular understanding of acute and injury-evoked heat temperature sensation. ThermoTRPV channels are activated by partially overlapping temperatures ranging from warm to supra-threshold noxious heat. TRPV1 is activated by noxious heat temperature whereas TRPV3 can be activated by warm as well as noxious heat temperatures. Loss-of-function studies in single TRPV1 and TRPV3 knock-out mice have shown that heat temperature sensation is not completely abolished suggesting functional redundancies among these two channels and highlighting the need of a detailed analysis of TRPV1::TRPV3 double knock-out mice (V1V3dKO) which is hampered by the close proximity of the loci expressing the two channels. Here we describe the generation of a novel mouse model in which trpv1 and trpv3 genes have been inactivated using bacterial artificial chromosome (BAC)-based homologous recombination in embryonic stem cells. In these mice, using classical thermosensory tests such hot plate, tail flick and the thermotaxis gradient paradigms, we confirm that TRPV1 is the master channel for sensing noxious heat temperatures and identify a cooperative role of TRPV1 and TRPV3 for sensing a well-defined window of acute moderate heat temperature. Using the dynamic hot plate assay, we unravel an intriguing and unexpected pronounced escape behavior in TRPV1 knock-out mice that was attenuated in the V1V3dKO. Together, and in agreement with the temperature activation overlap between TRPV1 and TRPV3 channels, our data provide in vivo evidence of a cooperative role between skin-derived TRPV3 and primary sensory neurons-enriched TRPV1 in modulation of moderate and noxious heat temperature sensation and suggest that other mechanisms are required for heat temperature sensation.

  2. Aggressive Behavior and Altered Amounts of Brain Serotonin and Norepinephrine in Mice Lacking MAOA

    Science.gov (United States)

    Cases, Olivier; Grimsby, Joseph; Gaspar, Patricia; Chen, Kevin; Pournin, Sandrine; Müller, Ulrike; Aguet, Michel; Babinet, Charles; Shih, Jean Chen; De Maeyer, Edward

    2010-01-01

    Deficiency in monoamine oxidase A (MAOA), an enzyme that degrades serotonin and norepinephrine, has recently been shown to be associated with aggressive behavior in men of a Dutch family. A line of transgenic mice was isolated in which transgene integration caused a deletion in the gene encoding MAOA, providing an animal model of MAOA deficiency. In pup brains, serotonin concentrations were increased up to ninefold, and serotonin-like immunoreactivity was present in catecholaminergic neurons. In pup and adult brains, norepinephrine concentrations were increased up to twofold, and cytoarchitectural changes were observed in the somatosensory cortex. Pup behavioral alterations, including trembling, difficulty in righting, and fearfulness were reversed by the serotonin synthesis inhibitor parachlorophenylalanine. Adults manifested a distinct behavioral syndrome, including enhanced aggression in males. PMID:7792602

  3. Two-year body composition analyses of long-lived GHR null mice.

    Science.gov (United States)

    Berryman, Darlene E; List, Edward O; Palmer, Amanda J; Chung, Min-Yu; Wright-Piekarski, Jacob; Lubbers, Ellen; O'Connor, Patrick; Okada, Shigeru; Kopchick, John J

    2010-01-01

    Growth hormone receptor gene-disrupted (GHR-/-) mice exhibit increased life span and adipose tissue mass. Although this obese phenotype has been reported extensively for young adult male GHR-/- mice, data for females and for other ages in either gender are lacking. Thus, the purpose of this study was to evaluate body composition longitudinally in both male and female GHR-/- mice. Results show that GHR-/- mice have a greater percent fat mass with no significant difference in absolute fat mass throughout life. Lean mass shows an opposite trend with percent lean mass not significantly different between genotypes but absolute mass reduced in GHR-/- mice. Differences in body composition are more pronounced in male than in female mice, and both genders of GHR-/- mice show specific enlargement of the subcutaneous adipose depot. Along with previously published data, these results suggest a consistent and intriguing protective effect of excess fat mass in the subcutaneous region.

  4. Deficient CD4+ T cell priming and regression of CD8+ T cell functionality in virus-infected mice lacking a normal B cell compartment

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Kauffmann, Susanne Ørding; Thomsen, Allan Randrup

    2003-01-01

    of virus-specific CD4(+) T cells was markedly impaired in B(-/-) mice infected with either virus strain. Thus, our results indicate that B cells play an important role in antiviral immunity not only as Ab producers, but also in promoting an optimal and sustained T cell response. The T cell defects......In this study, we investigate the state of T cell-mediated immunity in B cell-deficient (B(-/-)) mice infected with two strains of lymphocytic choriomeningitis virus known to differ markedly in their capacity to persist. In B(-/-) C57BL mice infected with the more persisting virus, virus......-specific CD8(+) T cells are initially generated that are qualitatively similar to those in wild-type mice. However, although cell numbers are well sustained over time, the capacity to produce cytokines is rapidly impaired. In similarly infected B(-/-) BALB/c mice, virus-specific CD8(+) T cells are completely...

  5. Lack of centrioles and primary cilia in STIL−/− mouse embryos

    Science.gov (United States)

    David, Ahuvit; Liu, Fengying; Tibelius, Alexandra; Vulprecht, Julia; Wald, Diana; Rothermel, Ulrike; Ohana, Reut; Seitel, Alexander; Metzger, Jasmin; Ashery-Padan, Ruth; Meinzer, Hans-Peter; Gröne, Hermann-Josef; Izraeli, Shai; Krämer, Alwin

    2014-01-01

    Although most animal cells contain centrosomes, consisting of a pair of centrioles, their precise contribution to cell division and embryonic development is unclear. Genetic ablation of STIL, an essential component of the centriole replication machinery in mammalian cells, causes embryonic lethality in mice around mid gestation associated with defective Hedgehog signaling. Here, we describe, by focused ion beam scanning electron microscopy, that STIL−/− mouse embryos do not contain centrioles or primary cilia, suggesting that these organelles are not essential for mammalian development until mid gestation. We further show that the lack of primary cilia explains the absence of Hedgehog signaling in STIL−/− cells. Exogenous re-expression of STIL or STIL microcephaly mutants compatible with human survival, induced non-templated, de novo generation of centrioles in STIL−/− cells. Thus, while the abscence of centrioles is compatible with mammalian gastrulation, lack of centrioles and primary cilia impairs Hedgehog signaling and further embryonic development. PMID:25486474

  6. Linkage disequilibrium in wild mice.

    Directory of Open Access Journals (Sweden)

    Cathy C Laurie

    2007-08-01

    Full Text Available Crosses between laboratory strains of mice provide a powerful way of detecting quantitative trait loci for complex traits related to human disease. Hundreds of these loci have been detected, but only a small number of the underlying causative genes have been identified. The main difficulty is the extensive linkage disequilibrium (LD in intercross progeny and the slow process of fine-scale mapping by traditional methods. Recently, new approaches have been introduced, such as association studies with inbred lines and multigenerational crosses. These approaches are very useful for interval reduction, but generally do not provide single-gene resolution because of strong LD extending over one to several megabases. Here, we investigate the genetic structure of a natural population of mice in Arizona to determine its suitability for fine-scale LD mapping and association studies. There are three main findings: (1 Arizona mice have a high level of genetic variation, which includes a large fraction of the sequence variation present in classical strains of laboratory mice; (2 they show clear evidence of local inbreeding but appear to lack stable population structure across the study area; and (3 LD decays with distance at a rate similar to human populations, which is considerably more rapid than in laboratory populations of mice. Strong associations in Arizona mice are limited primarily to markers less than 100 kb apart, which provides the possibility of fine-scale association mapping at the level of one or a few genes. Although other considerations, such as sample size requirements and marker discovery, are serious issues in the implementation of association studies, the genetic variation and LD results indicate that wild mice could provide a useful tool for identifying genes that cause variation in complex traits.

  7. Lack of parvalbumin in mice leads to behavioral deficits relevant to all human autism core symptoms and related neural morphofunctional abnormalities.

    Science.gov (United States)

    Wöhr, M; Orduz, D; Gregory, P; Moreno, H; Khan, U; Vörckel, K J; Wolfer, D P; Welzl, H; Gall, D; Schiffmann, S N; Schwaller, B

    2015-03-10

    Gene mutations and gene copy number variants are associated with autism spectrum disorders (ASDs). Affected gene products are often part of signaling networks implicated in synapse formation and/or function leading to alterations in the excitation/inhibition (E/I) balance. Although the network of parvalbumin (PV)-expressing interneurons has gained particular attention in ASD, little is known on PV's putative role with respect to ASD. Genetic mouse models represent powerful translational tools for studying the role of genetic and neurobiological factors underlying ASD. Here, we report that PV knockout mice (PV(-/-)) display behavioral phenotypes with relevance to all three core symptoms present in human ASD patients: abnormal reciprocal social interactions, impairments in communication and repetitive and stereotyped patterns of behavior. PV-depleted mice also showed several signs of ASD-associated comorbidities, such as reduced pain sensitivity and startle responses yet increased seizure susceptibility, whereas no evidence for behavioral phenotypes with relevance to anxiety, depression and schizophrenia was obtained. Reduced social interactions and communication were also observed in heterozygous (PV(+/-)) mice characterized by lower PV expression levels, indicating that merely a decrease in PV levels might be sufficient to elicit core ASD-like deficits. Structural magnetic resonance imaging measurements in PV(-/-) and PV(+/-) mice further revealed ASD-associated developmental neuroanatomical changes, including transient cortical hypertrophy and cerebellar hypoplasia. Electrophysiological experiments finally demonstrated that the E/I balance in these mice is altered by modification of both inhibitory and excitatory synaptic transmission. On the basis of the reported changes in PV expression patterns in several, mostly genetic rodent models of ASD, we propose that in these models downregulation of PV might represent one of the points of convergence, thus providing a

  8. Deletion of Lkb1 in pro-opiomelanocortin neurons impairs peripheral glucose homeostasis in mice.

    Science.gov (United States)

    Claret, Marc; Smith, Mark A; Knauf, Claude; Al-Qassab, Hind; Woods, Angela; Heslegrave, Amanda; Piipari, Kaisa; Emmanuel, Julian J; Colom, André; Valet, Philippe; Cani, Patrice D; Begum, Ghazala; White, Anne; Mucket, Phillip; Peters, Marco; Mizuno, Keiko; Batterham, Rachel L; Giese, K Peter; Ashworth, Alan; Burcelin, Remy; Ashford, Michael L; Carling, David; Withers, Dominic J

    2011-03-01

    AMP-activated protein kinase (AMPK) signaling acts as a sensor of nutrients and hormones in the hypothalamus, thereby regulating whole-body energy homeostasis. Deletion of Ampkα2 in pro-opiomelanocortin (POMC) neurons causes obesity and defective neuronal glucose sensing. LKB1, the Peutz-Jeghers syndrome gene product, and Ca(2+)-calmodulin-dependent protein kinase kinase β (CaMKKβ) are key upstream activators of AMPK. This study aimed to determine their role in POMC neurons upon energy and glucose homeostasis regulation. Mice lacking either Camkkβ or Lkb1 in POMC neurons were generated, and physiological, electrophysiological, and molecular biology studies were performed. Deletion of Camkkβ in POMC neurons does not alter energy homeostasis or glucose metabolism. In contrast, female mice lacking Lkb1 in POMC neurons (PomcLkb1KO) display glucose intolerance, insulin resistance, impaired suppression of hepatic glucose production, and altered expression of hepatic metabolic genes. The underlying cellular defect in PomcLkb1KO mice involves a reduction in melanocortin tone caused by decreased α-melanocyte-stimulating hormone secretion. However, Lkb1-deficient POMC neurons showed normal glucose sensing, and body weight was unchanged in PomcLkb1KO mice. Our findings demonstrate that LKB1 in hypothalamic POMC neurons plays a key role in the central regulation of peripheral glucose metabolism but not body-weight control. This phenotype contrasts with that seen in mice lacking AMPK in POMC neurons with defects in body-weight regulation but not glucose homeostasis, which suggests that LKB1 plays additional functions distinct from activating AMPK in POMC neurons.

  9. RhoE deficiency produces postnatal lethality, profound motor deficits and neurodevelopmental delay in mice.

    Directory of Open Access Journals (Sweden)

    Enric Mocholí

    Full Text Available Rnd proteins are a subfamily of Rho GTPases involved in the control of actin cytoskeleton dynamics and other cell functions such as motility, proliferation and survival. Unlike other members of the Rho family, Rnd proteins lack GTPase activity and therefore remain constitutively active. We have recently described that RhoE/Rnd3 is expressed in the Central Nervous System and that it has a role in promoting neurite formation. Despite their possible relevance during development, the role of Rnd proteins in vivo is not known. To get insight into the in vivo function of RhoE we have generated mice lacking RhoE expression by an exon trapping cassette. RhoE null mice (RhoE gt/gt are smaller at birth, display growth retardation and early postnatal death since only half of RhoE gt/gt mice survive beyond postnatal day (PD 15 and 100% are dead by PD 29. RhoE gt/gt mice show an abnormal body position with profound motor impairment and impaired performance in most neurobehavioral tests. Null mutant mice are hypoactive, show an immature locomotor pattern and display a significant delay in the appearance of the hindlimb mature responses. Moreover, they perform worse than the control littermates in the wire suspension, vertical climbing and clinging, righting reflex and negative geotaxis tests. Also, RhoE ablation results in a delay of neuromuscular maturation and in a reduction in the number of spinal motor neurons. Finally, RhoE gt/gt mice lack the common peroneal nerve and, consequently, show a complete atrophy of the target muscles. This is the first model to study the in vivo functions of a member of the Rnd subfamily of proteins, revealing the important role of Rnd3/RhoE in the normal development and suggesting the possible involvement of this protein in neurological disorders.

  10. Protein tyrosine phosphatase PTP1B is involved in hippocampal synapse formation and learning.

    Directory of Open Access Journals (Sweden)

    Federico Fuentes

    Full Text Available ER-bound PTP1B is expressed in hippocampal neurons, and accumulates among neurite contacts. PTP1B dephosphorylates ß-catenin in N-cadherin complexes ensuring cell-cell adhesion. Here we show that endogenous PTP1B, as well as expressed GFP-PTP1B, are present in dendritic spines of hippocampal neurons in culture. GFP-PTP1B overexpression does not affect filopodial density or length. In contrast, impairment of PTP1B function or genetic PTP1B-deficiency leads to increased filopodia-like dendritic spines and a reduction in mushroom-like spines, while spine density is unaffected. These morphological alterations are accompanied by a disorganization of pre- and post-synapses, as judged by decreased clustering of synapsin-1 and PSD-95, and suggest a dynamic synaptic phenotype. Notably, levels of ß-catenin-Tyr-654 phosphorylation increased ∼5-fold in the hippocampus of adult PTP1B(-/- (KO mice compared to wild type (WT mice and this was accompanied by a reduction in the amount of ß-catenin associated with N-cadherin. To determine whether PTP1B-deficiency alters learning and memory, we generated mice lacking PTP1B in the hippocampus and cortex (PTP1B(fl/fl-Emx1-Cre. PTP1B(fl/fl-Emx1-Cre mice displayed improved performance in the Barnes maze (decreased time to find and enter target hole, utilized a more efficient strategy (cued, and had better recall compared to WT controls. Our results implicate PTP1B in structural plasticity within the hippocampus, likely through modulation of N-cadherin function by ensuring dephosphorylation of ß-catenin on Tyr-654. Disruption of hippocampal PTP1B function or expression leads to elongation of dendritic filopodia and improved learning and memory, demonstrating an exciting novel role for this phosphatase.

  11. Adaptation of a ladder beam walking task to assess locomotor recovery in mice following spinal cord injury

    Science.gov (United States)

    Cummings, Brian J.; Engesser-Cesar, Christie; Anderson, Aileen J.

    2007-01-01

    Locomotor impairments after spinal cord injury (SCI) are often assessed using open-field rating scales. These tasks have the advantage of spanning the range from complete paralysis to normal walking; however, they lack sensitivity at specific levels of recovery. Additionally, most supplemental assessments were developed in rats, not mice. For example, the horizontal ladder beam has been used to measure recovery in the rat after SCI. This parametric task results in a videotaped archival record of the event, is easily administered, and is unambiguously scored. Although a ladder beam apparatus for mice is available, its use in the assessment of recovery in SCI mice is rare, possibly because normative data for uninjured mice and the type of step misplacements injured mice exhibit is lacking. We report the development of a modified ladder beam instrument and scoring system to measure hindlimb recovery in vertebral T9 contusion spinal cord injured mice. The mouse ladder beam allows for the use of standard parametric statistical tests to assess locomotor recovery. Ladder beam performance is consistent across four strains of mice, there are no sex differences, and inter-rater reliability between observers is high. The ladder beam score is proportional to injury severity and can be used to easily separate mice capable of weight-supported stance up to mice with consistent forelimb to hindlimb coordination. Critically, horizontal ladder beam testing discriminates between mice that score identically in terms of stepping frequency in open-field testing. PMID:17197044

  12. Adaptation of a ladder beam walking task to assess locomotor recovery in mice following spinal cord injury.

    Science.gov (United States)

    Cummings, Brian J; Engesser-Cesar, Christie; Cadena, Gilbert; Anderson, Aileen J

    2007-02-27

    Locomotor impairments after spinal cord injury (SCI) are often assessed using open-field rating scales. These tasks have the advantage of spanning the range from complete paralysis to normal walking; however, they lack sensitivity at specific levels of recovery. Additionally, most supplemental assessments were developed in rats, not mice. For example, the horizontal ladder beam has been used to measure recovery in the rat after SCI. This parametric task results in a videotaped archival record of the event, is easily administered, and is unambiguously scored. Although a ladder beam apparatus for mice is available, its use in the assessment of recovery in SCI mice is rare, possibly because normative data for uninjured mice and the type of step misplacements injured mice exhibit is lacking. We report the development of a modified ladder beam instrument and scoring system to measure hindlimb recovery in vertebral T9 contusion spinal cord injured mice. The mouse ladder beam allows for the use of standard parametric statistical tests to assess locomotor recovery. Ladder beam performance is consistent across four strains of mice, there are no sex differences, and inter-rater reliability between observers is high. The ladder beam score is proportional to injury severity and can be used to easily separate mice capable of weight-supported stance up to mice with consistent forelimb to hindlimb coordination. Critically, horizontal ladder beam testing discriminates between mice that score identically in terms of stepping frequency in open-field testing.

  13. Exhaustion of CTL memory and recrudescence of viremia in lymphocytic choriomeningitis virus-infected MHC class II-deficient mice and B cell-deficient mice

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Johansen, J; Marker, O

    1996-01-01

    To study the contribution of CD4+ T cells and B cells to antiviral immunity and long term virus control, MHC class II-deficient and B cell-deficient mice were infected with lymphocytic choriomeningitis virus. In class II-deficient mice, which lack CD4+ T cells, the primary CTL response is virtually...... this phenomenon could reflect participation of B cells and/or Abs in long term virus control, similar experiments were performed with mice that do not have mature B cells because of a disrupted membrane exon of the mu chain gene. In these mice, the cell-mediated immune response was slightly delayed, but transient...... and that in their absence, the virus-specific CTL potential becomes exhausted. Together our results indicate that while CD8+ cells play a dominant role in acute virus control, all three major components of the immune system are required for long term virus control....

  14. Characterization of NGF, trkANGFR, and p75NTR in Retina of Mice Lacking Reelin Glycoprotein

    Directory of Open Access Journals (Sweden)

    Bijorn Omar Balzamino

    2014-01-01

    Full Text Available Both Reelin and Nerve Growth Factor (NGF exert crucial roles in retinal development. Retinogenesis is severely impaired in E-reeler mice, a model of Reelin deficiency showing specific Green Fluorescent Protein expression in Rod Bipolar Cells (RBCs. Since no data are available on Reelin and NGF cross-talk, NGF and trkANGFR/ p75NTR expression was investigated in retinas from E-reeler versus control mice, by confocal microscopy, Western blotting, and real time PCR analysis. A scattered increase of NGF protein was observed in the Ganglion Cell Layer and more pronounced in the Inner Nuclear Layer (INL. A selective increase of p75NTR was detected in most of RBCs and in other cell subtypes of INL. On the contrary, a slight trend towards a decrease was detected for trkANGFR, albeit not significant. Confocal data were validated by Western blot and real time PCR. Finally, the decreased trkANGFR/ p75NTR ratio, representative of p75NTR increase, significantly correlated with E-reeler versus E-control. These data indicate that NGF-trkANGFR/ p75NTR is affected in E-reeler retina and that p75NTR might represent the main NGF receptor involved in the process. This first NGF-trkANGFR/ p75NTR characterization suggests that E-reeler might be suitable for exploring Reelin-NGF cross-talk, representing an additional information source in those pathologies characterized by retinal degeneration.

  15. Functionally enhanced brown adipose tissue in Ames dwarf mice.

    Science.gov (United States)

    Darcy, Justin; Bartke, Andrzej

    2017-01-02

    Reduced insulin-like growth factor 1/insulin signaling (IIS) has been linked to extended longevity in species ranging from yeast to mammals. In mammals, this is exemplified in Ames dwarf (Prop1 df/df ) mice, which have a 40%-60% increase in longevity (males and females, respectively) due to their recessive Prop1 loss-of-function mutation that results in lack of growth hormone (GH), thyroid-stimulating hormone and prolactin. Our laboratory has previously shown that Ames dwarf mice have functionally unique white adipose tissue (WAT) that improves, rather than impairs, insulin sensitivity. Because GH and thyroid hormone are integral to adipose tissue development and function, we hypothesized that brown adipose tissue (BAT) in Ames dwarf mice may also be functionally unique and/or enhanced. Here, we elaborate on our recent findings, which demonstrate that BAT is functionally enhanced in Ames dwarf mice, and suggest that BAT removal in these mice results in utilization of WAT depots as an energy source. We also discuss how our findings compare to those in other long-lived dwarf mice with altered IIS, which unlike Ames dwarf mice, are essentially euthyroid. Lastly, we provide some insights into the implications of these findings and discuss some of the necessary future work in this area.

  16. Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

    Science.gov (United States)

    Aryanpour, J; Hafizi, A; Modabber, F

    1980-03-01

    Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG seems to be dependent upon T-cells in Toxoplasma-infected mice.

  17. Deletion of Lkb1 in Pro-Opiomelanocortin Neurons Impairs Peripheral Glucose Homeostasis in Mice

    Science.gov (United States)

    Claret, Marc; Smith, Mark A.; Knauf, Claude; Al-Qassab, Hind; Woods, Angela; Heslegrave, Amanda; Piipari, Kaisa; Emmanuel, Julian J.; Colom, André; Valet, Philippe; Cani, Patrice D.; Begum, Ghazala; White, Anne; Mucket, Phillip; Peters, Marco; Mizuno, Keiko; Batterham, Rachel L.; Giese, K. Peter; Ashworth, Alan; Burcelin, Remy; Ashford, Michael L.; Carling, David; Withers, Dominic J.

    2011-01-01

    OBJECTIVE AMP-activated protein kinase (AMPK) signaling acts as a sensor of nutrients and hormones in the hypothalamus, thereby regulating whole-body energy homeostasis. Deletion of Ampkα2 in pro-opiomelanocortin (POMC) neurons causes obesity and defective neuronal glucose sensing. LKB1, the Peutz-Jeghers syndrome gene product, and Ca2+-calmodulin–dependent protein kinase kinase β (CaMKKβ) are key upstream activators of AMPK. This study aimed to determine their role in POMC neurons upon energy and glucose homeostasis regulation. RESEARCH DESIGN AND METHODS Mice lacking either Camkkβ or Lkb1 in POMC neurons were generated, and physiological, electrophysiological, and molecular biology studies were performed. RESULTS Deletion of Camkkβ in POMC neurons does not alter energy homeostasis or glucose metabolism. In contrast, female mice lacking Lkb1 in POMC neurons (PomcLkb1KO) display glucose intolerance, insulin resistance, impaired suppression of hepatic glucose production, and altered expression of hepatic metabolic genes. The underlying cellular defect in PomcLkb1KO mice involves a reduction in melanocortin tone caused by decreased α-melanocyte–stimulating hormone secretion. However, Lkb1-deficient POMC neurons showed normal glucose sensing, and body weight was unchanged in PomcLkb1KO mice. CONCLUSIONS Our findings demonstrate that LKB1 in hypothalamic POMC neurons plays a key role in the central regulation of peripheral glucose metabolism but not body-weight control. This phenotype contrasts with that seen in mice lacking AMPK in POMC neurons with defects in body-weight regulation but not glucose homeostasis, which suggests that LKB1 plays additional functions distinct from activating AMPK in POMC neurons. PMID:21266325

  18. Scaffold proteins LACK and TRACK as potential drug targets in kinetoplastid parasites: Development of inhibitors

    Directory of Open Access Journals (Sweden)

    Nir Qvit

    2016-04-01

    Full Text Available Parasitic diseases cause ∼500,000 deaths annually and remain a major challenge for therapeutic development. Using a rational design based approach, we developed peptide inhibitors with anti-parasitic activity that were derived from the sequences of parasite scaffold proteins LACK (Leishmania's receptor for activated C-kinase and TRACK (Trypanosoma receptor for activated C-kinase. We hypothesized that sequences in LACK and TRACK that are conserved in the parasites, but not in the mammalian ortholog, RACK (Receptor for activated C-kinase, may be interaction sites for signaling proteins that are critical for the parasites' viability. One of these peptides exhibited leishmanicidal and trypanocidal activity in culture. Moreover, in infected mice, this peptide was also effective in reducing parasitemia and increasing survival without toxic effects. The identified peptide is a promising new anti-parasitic drug lead, as its unique features may limit toxicity and drug-resistance, thus overcoming central limitations of most anti-parasitic drugs. Keywords: Chagas disease, Leishmaniasis, Peptide, LACK, TRACK, Scaffold protein

  19. Milk lacking α-casein leads to permanent reduction in body size in mice.

    Directory of Open Access Journals (Sweden)

    Andreas F Kolb

    Full Text Available The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate.We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight.

  20. Milk Lacking α-Casein Leads to Permanent Reduction in Body Size in Mice

    Science.gov (United States)

    Kolb, Andreas F.; Huber, Reinhard C.; Lillico, Simon G.; Carlisle, Ailsa; Robinson, Claire J.; Neil, Claire; Petrie, Linda; Sorensen, Dorte B.; Olsson, I. Anna S.; Whitelaw, C. Bruce A.

    2011-01-01

    The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate. We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight. PMID:21789179

  1. Muscle Structure Influences Utrophin Expression in mdx Mice

    Science.gov (United States)

    Banks, Glen B.; Combs, Ariana C.; Odom, Guy L.; Bloch, Robert J.; Chamberlain, Jeffrey S.

    2014-01-01

    Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder caused by mutations in the dystrophin gene. To examine the influence of muscle structure on the pathogenesis of DMD we generated mdx4cv:desmin double knockout (dko) mice. The dko male mice died of apparent cardiorespiratory failure at a median age of 76 days compared to 609 days for the desmin−/− mice. An ∼2.5 fold increase in utrophin expression in the dko skeletal muscles prevented necrosis in ∼91% of 1a, 2a and 2d/x fiber-types. In contrast, utrophin expression was reduced in the extrasynaptic sarcolemma of the dko fast 2b fibers leading to increased membrane fragility and dystrophic pathology. Despite lacking extrasynaptic utrophin, the dko fast 2b fibers were less dystrophic than the mdx4cv fast 2b fibers suggesting utrophin-independent mechanisms were also contributing to the reduced dystrophic pathology. We found no overt change in the regenerative capacity of muscle stem cells when comparing the wild-type, desmin−/−, mdx4cv and dko gastrocnemius muscles injured with notexin. Utrophin could form costameric striations with α-sarcomeric actin in the dko to maintain the integrity of the membrane, but the lack of restoration of the NODS (nNOS, α-dystrobrevin 1 and 2, α1-syntrophin) complex and desmin coincided with profound changes to the sarcomere alignment in the diaphragm, deposition of collagen between the myofibers, and impaired diaphragm function. We conclude that the dko mice may provide new insights into the structural mechanisms that influence endogenous utrophin expression that are pertinent for developing a therapy for DMD. PMID:24922526

  2. Activation of inflammatory signaling by lipopolysaccharide produces a prolonged increase of voluntary alcohol intake in mice

    Science.gov (United States)

    Blednov, Y.A.; Benavidez, J.M.; Geil, C.; Perra, S.; Morikawa, H.; Harris, R.A.

    2011-01-01

    Previous studies showed that mice with genetic predisposition for high alcohol consumption as well as human alcoholics show changes in brain expression of genes related to immune signaling. In addition, mutant mice lacking genes related to immune function show decreased alcohol consumption (Blednov et al., in press), suggesting that immune signaling promotes alcohol consumption. To test the possibility that activation of immune signaling will increase alcohol consumption, we treated mice with lipopolysaccaride (LPS; 1 mg/kg, i.p.) and tested alcohol consumption in the continuous two-bottle choice test. To take advantage of the long-lasting activation of brain immune signaling by LPS, we measured drinking beginning one week or one month after LPS treatment and continued the studies for several months. LPS produced persistent increases in alcohol consumption in C57/Bl6 J (B6) inbred mice, FVBxB6F1 and B6xNZBF1 hybrid mice, but not in FVB inbred mice. To determine if this effect of LPS is mediated through binding to TLR4, we tested mice lacking CD14, a key component of TLR4 signaling. These null mutants showed no increase of alcohol intake after treatment with LPS. LPS treatment decreased ethanol-conditioned taste aversion but did not alter ethanol-conditioned place preference (B6xNZBF1 mice). Electro-physiological studies of dopamine neurons in the ventral tegmental area showed that pretreatment of mice with LPS decreased the neuronal firing rate. These results suggest that activation of immune signaling promotes alcohol consumption and alters certain aspects of alcohol reward/aversion. PMID:21266194

  3. Plasma biomarkers of liver injury and inflammation demonstrate a lack of apoptosis during obstructive cholestasis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Woolbright, Benjamin L. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Antoine, Daniel J.; Jenkins, Rosalind E. [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Bajt, Mary Lynn [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Park, B. Kevin [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2013-12-15

    Cholestasis is a pathological common component of numerous liver diseases that results in hepatotoxicity, inflammation, and cirrhosis when untreated. While the predominant hypothesis in cholestatic liver injury remains hepatocyte apoptosis due to direct toxicity of hydrophobic bile acid exposure, recent work suggests that the injury occurs through inflammatory necrosis. In order to resolve this controversy, we used novel plasma biomarkers to assess the mechanisms of cell death during early cholestatic liver injury. C57Bl/6 mice underwent bile duct ligation (BDL) for 6–72 h, or sham operation. Another group of mice were given D-galactosamine and endotoxin as a positive control for apoptosis and inflammatory necrosis. Plasma levels of full length cytokeratin-18 (FL-K18), microRNA-122 (miR-122) and high mobility group box-1 protein (HMGB1) increased progressively after BDL with peak levels observed after 48 h. These results indicate extensive cell necrosis after BDL, which is supported by the time course of plasma alanine aminotransferase activities and histology. In contrast, plasma caspase-3 activity, cleaved caspase-3 protein and caspase-cleaved cytokeratin-18 fragments (cK18) were not elevated at any time during BDL suggesting the absence of apoptosis. In contrast, all plasma biomarkers of necrosis and apoptosis were elevated 6 h after Gal/End treatment. In addition, acetylated HMGB1, a marker for macrophage and monocyte activation, was increased as early as 12 h but mainly at 48–72 h. However, progressive neutrophil accumulation in the area of necrosis started at 6 h after BDL. In conclusion, these data indicate that early cholestatic liver injury in mice is an inflammatory event, and occurs through necrosis with little evidence for apoptosis. - Highlights: • The mechanism of cell death during cholestasis remains a controversial topic. • Plasma biomarkers offer new insight into cell death after bile duct ligation. • Cytokeratin-18, microRNA-122 and HMGB

  4. Plasma biomarkers of liver injury and inflammation demonstrate a lack of apoptosis during obstructive cholestasis in mice

    International Nuclear Information System (INIS)

    Woolbright, Benjamin L.; Antoine, Daniel J.; Jenkins, Rosalind E.; Bajt, Mary Lynn; Park, B. Kevin; Jaeschke, Hartmut

    2013-01-01

    Cholestasis is a pathological common component of numerous liver diseases that results in hepatotoxicity, inflammation, and cirrhosis when untreated. While the predominant hypothesis in cholestatic liver injury remains hepatocyte apoptosis due to direct toxicity of hydrophobic bile acid exposure, recent work suggests that the injury occurs through inflammatory necrosis. In order to resolve this controversy, we used novel plasma biomarkers to assess the mechanisms of cell death during early cholestatic liver injury. C57Bl/6 mice underwent bile duct ligation (BDL) for 6–72 h, or sham operation. Another group of mice were given D-galactosamine and endotoxin as a positive control for apoptosis and inflammatory necrosis. Plasma levels of full length cytokeratin-18 (FL-K18), microRNA-122 (miR-122) and high mobility group box-1 protein (HMGB1) increased progressively after BDL with peak levels observed after 48 h. These results indicate extensive cell necrosis after BDL, which is supported by the time course of plasma alanine aminotransferase activities and histology. In contrast, plasma caspase-3 activity, cleaved caspase-3 protein and caspase-cleaved cytokeratin-18 fragments (cK18) were not elevated at any time during BDL suggesting the absence of apoptosis. In contrast, all plasma biomarkers of necrosis and apoptosis were elevated 6 h after Gal/End treatment. In addition, acetylated HMGB1, a marker for macrophage and monocyte activation, was increased as early as 12 h but mainly at 48–72 h. However, progressive neutrophil accumulation in the area of necrosis started at 6 h after BDL. In conclusion, these data indicate that early cholestatic liver injury in mice is an inflammatory event, and occurs through necrosis with little evidence for apoptosis. - Highlights: • The mechanism of cell death during cholestasis remains a controversial topic. • Plasma biomarkers offer new insight into cell death after bile duct ligation. • Cytokeratin-18, microRNA-122 and HMGB

  5. Lipid metabolism and body composition in Gclm(-/-) mice

    Energy Technology Data Exchange (ETDEWEB)

    Kendig, Eric L. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Chen, Ying [Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver, Aurora, CO 80045 (United States); Krishan, Mansi; Johansson, Elisabet; Schneider, Scott N. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Genter, Mary Beth; Nebert, Daniel W. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Shertzer, Howard G., E-mail: shertzhg@ucmail.uc.edu [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States)

    2011-12-15

    In humans and experimental animals, high fat diets (HFD) are associated with risk factors for metabolic diseases, such as excessive weight gain and adiposity, insulin resistance and fatty liver. Mice lacking the glutamate-cysteine ligase modifier subunit gene (Gclm(-/-)) and deficient in glutathione (GSH), are resistant to HFD-mediated weight gain. Herein, we evaluated Gclm-associated regulation of energy metabolism, oxidative stress, and glucose and lipid homeostasis. C57BL/6J Gclm(-/-) mice and littermate wild-type (WT) controls received a normal diet or an HFD for 11 weeks. HFD-fed Gclm(-/-) mice did not display a decreased respiratory quotient, suggesting that they are unable to process lipid for metabolism. Although dietary energy consumption and intestinal lipid absorption were unchanged in Gclm(-/-) mice, feeding these mice an HFD did not produce excess body weight nor fat storage. Gclm(-/-) mice displayed higher basal metabolic rates resulting from higher activities of liver mitochondrial NADH-CoQ oxidoreductase, thus elevating respiration. Although Gclm(-/-) mice exhibited strong systemic and hepatic oxidative stress responses, HFD did not promote glucose intolerance or insulin resistance. Furthermore, HFD-fed Gclm(-/-) mice did not develop fatty liver, likely resulting from very low expression levels of genes encoding lipid metabolizing enzymes. We conclude that Gclm is involved in the regulation of basal metabolic rate and the metabolism of dietary lipid. Although Gclm(-/-) mice display a strong oxidative stress response, they are protected from HFD-induced excessive weight gain and adipose deposition, insulin resistance and steatosis. -- Highlights: Black-Right-Pointing-Pointer A high fat diet does not produce body weight and fat gain in Gclm(-/-) mice. Black-Right-Pointing-Pointer A high fat diet does not induce steatosis or insulin resistance in Gclm(-/-) mice. Black-Right-Pointing-Pointer Gclm(-/-) mice have high basal metabolism and mitochondrial

  6. Lack of chemokine signaling through CXCR5 causes increased mortality, ventricular dilatation and deranged matrix during cardiac pressure overload.

    Directory of Open Access Journals (Sweden)

    Anne Waehre

    Full Text Available RATIONALE: Inflammatory mechanisms have been suggested to play a role in the development of heart failure (HF, but a role for chemokines is largely unknown. Based on their role in inflammation and matrix remodeling in other tissues, we hypothesized that CXCL13 and CXCR5 could be involved in cardiac remodeling during HF. OBJECTIVE: We sought to analyze the role of the chemokine CXCL13 and its receptor CXCR5 in cardiac pathophysiology leading to HF. METHODS AND RESULTS: Mice harboring a systemic knockout of the CXCR5 (CXCR5(-/- displayed increased mortality during a follow-up of 80 days after aortic banding (AB. Following three weeks of AB, CXCR5(-/- developed significant left ventricular (LV dilatation compared to wild type (WT mice. Microarray analysis revealed altered expression of several small leucine-rich proteoglycans (SLRPs that bind to collagen and modulate fibril assembly. Protein levels of fibromodulin, decorin and lumican (all SLRPs were significantly reduced in AB CXCR5(-/- compared to AB WT mice. Electron microscopy revealed loosely packed extracellular matrix with individual collagen fibers and small networks of proteoglycans in AB CXCR5(-/- mice. Addition of CXCL13 to cultured cardiac fibroblasts enhanced the expression of SLRPs. In patients with HF, we observed increased myocardial levels of CXCR5 and SLRPs, which was reversed following LV assist device treatment. CONCLUSIONS: Lack of CXCR5 leads to LV dilatation and increased mortality during pressure overload, possibly via lack of an increase in SLRPs. This study demonstrates a critical role of the chemokine CXCL13 and CXCR5 in survival and maintaining of cardiac structure upon pressure overload, by regulating proteoglycans essential for correct collagen assembly.

  7. Lack of genotoxic effect of food dyes amaranth, sunset yellow and tartrazine and their metabolites in the gut micronucleus assay in mice.

    Science.gov (United States)

    Poul, Martine; Jarry, Gérard; Elhkim, Mostafa Ould; Poul, Jean-Michel

    2009-02-01

    The food dyes amaranth, sunset yellow and tartrazine were administered twice, at 24h intervals, by oral gavage to mice and assessed in the in vivo gut micronucleus test for genotoxic effects (frequency of micronucleated cells) and toxicity (apoptotic and mitotic cells). The concentrations of each compound and their main metabolites (sulfanilic acid and naphthionic acid) were measured in faeces during a 24-h period after single oral administrations of the food dyes to mice. Parent dye compounds and their main aromatic amine metabolites were detected in significant amounts in the environment of colonic cells. Acute oral exposure to food dye additives amaranth, sunset yellow and tartrazine did not induce genotoxic effect in the micronucleus gut assay in mice at doses up to 2000 mg/kg b.w. Food dyes administration increased the mitotic cells at all dose levels when compared to controls. These results suggest that the transient DNA damages previously observed in the colon of mice treated by amaranth and tartrazine by the in vivo comet assay [Sasaki, Y.F., Kawaguchi, S., Kamaya, A., Ohshita, M., Kabasawa, K., Iwama, K., Taniguchi, K., Tsuda, S., 2002. The comet assay with 8 mouse organs: results with 39 currently used food additives. Mutat. Res. 519, 103-119] are unable to be fixed in stable genotoxic lesions and might be partly explained by local cytotoxicity of the dyes.

  8. p21WAF1/Cip1/Sdi1 knockout mice respond to doxorubicin with reduced cardiotoxicity

    International Nuclear Information System (INIS)

    Terrand, Jerome; Xu, Beibei; Morrissy, Steve; Dinh, Thai Nho; Williams, Stuart; Chen, Qin M.

    2011-01-01

    Doxorubicin (Dox) is an antineoplastic agent that can cause cardiomyopathy in humans and experimental animals. As an inducer of reactive oxygen species and a DNA damaging agent, Dox causes elevated expression of p21 WAF1/Cip1/Sdi1 (p21) gene. Elevated levels of p21 mRNA and p21 protein have been detected in the myocardium of mice following Dox treatment. With chronic treatment of Dox, wild type (WT) animals develop cardiomyopathy evidenced by elongated nuclei, mitochondrial swelling, myofilamental disarray, reduced cardiac output, reduced ejection fraction, reduced left ventricular contractility, and elevated expression of ANF gene. In contrast, p21 knockout (p21KO) mice did not show significant changes in the same parameters in response to Dox treatment. In an effort to understand the mechanism of the resistance against Dox induced cardiomyopathy, we measured levels of antioxidant enzymes and found that p21KO mice did not contain elevated basal or inducible levels of glutathione peroxidase and catalase. Measurements of 6 circulating cytokines indicated elevation of IL-6, IL-12, IFNγ and TNFα in Dox treated WT mice but not p21KO mice. Dox induced elevation of IL-6 mRNA was detected in the myocardium of WT mice but not p21KO mice. While the mechanism of the resistance against Dox induced cardiomyopathy remains unclear, lack of inflammatory response may contribute to the observed cardiac protection in p21KO mice. -- Highlights: ► Doxorubicin induces p21 elevation in the myocardium. ► Doxorubicin causes dilated cardiomyopathy in wild type mice. ► p21 Knockout mice are resistant against doxorubicin induced cardiomyopathy. ► Lack of inflammatory response correlates with the resistance in p21 knockout mice.

  9. Novel Hg2+-Induced Nephropathy in Rats and Mice Lacking Mrp2: Evidence of Axial Heterogeneity in the Handling of Hg2+ Along the Proximal Tubule

    Science.gov (United States)

    Zalups, Rudolfs K.; Joshee, Lucy; Bridges, Christy C.

    2014-01-01

    The role of the multi-resistance protein 2 (Mrp2) in the nephropathy induced by inorganic mercuric mercury (Hg2+) was studied in rats (TR−) and mice (Mrp2−/−), which lack functional Mrp2, and control animals. Animals were exposed to nephrotoxic doses of HgCl2. Forty-eight or 24 hours after exposure, tissues were harvested and analyzed for Hg content and markers of injury. Histological analyses revealed that the proximal tubular segments affected pathologically by Hg2+ were significantly different between Mrp2-deficient animals and controls. In the absence of Mrp2, cellular injury localized almost exclusively in proximal tubular segments in the subcapsular (S1) to midcortical regions (early S2) of the kidney. In control animals, cellular death occurred mainly in the proximal tubular segments in the inner cortex (late S2) and outer stripe of the outer medulla (S3). These differences in renal pathology indicate that axial heterogeneity exists along the proximal tubule with respect to how mercuric ions are handled. Total renal and hepatic accumulation of mercury was also greater in animals lacking Mrp2 than in controls, indicating that Mrp2 normally plays a significant role in eliminating mercuric ions from within proximal tubular cells and hepatocytes. Analyses of plasma creatinine, BUN, and renal expression of Kim-1 and Ngal tend to support the severity of the nephropathies detected histologically. Collectively, our findings indicate that a fraction of mercuric ions is normally secreted by Mrp2 in early portions of proximal tubules into the lumen and then is absorbed downstream in straight portions, where mercuric species typically induce toxic effects. PMID:25145654

  10. Lack of endogenous parathyroid hormone delays fracture healing by inhibiting vascular endothelial growth factor‑mediated angiogenesis.

    Science.gov (United States)

    Ding, Qingfeng; Sun, Peng; Zhou, Hao; Wan, Bowen; Yin, Jian; Huang, Yao; Li, Qingqing; Yin, Guoyong; Fan, Jin

    2018-07-01

    Intermittent low‑dose injections of parathyroid hormone (PTH) have been reported to exert bone anabolic effects and to promote fracture healing. As an important proangiogenic cytokine, vascular endothelial growth factor (VEGF) is secreted by bone marrow mesenchymal stem cells (BMSCs) and osteoblasts, and serves a crucial regulatory role in the process of vascular development and regeneration. To investigate whether lack of endogenous PTH causes reduced angiogenic capacity and thereby delays the process of fracture healing by downregulating the VEGF signaling pathway, a PTH knockout (PTHKO) mouse fracture model was generated. Fracture healing was observed using X‑ray and micro‑computerized tomography. Bone anabolic and angiogenic markers were analyzed by immunohistochemistry and western blot analysis. The expression levels of VEGF and associated signaling pathways in murine BMSC‑derived osteoblasts were measured by quantitative polymerase chain reaction and western blot analysis. The expression levels of protein kinase A (PKA), phosphorylated‑serine/threonine protein kinase (pAKT), hypoxia‑inducible factor‑1α (HIF1α) and VEGF were significantly decreased in BMSC‑derived osteoblasts from PTHKO mice. In addition, positive platelet endothelial cell adhesion molecule staining was reduced in PTHKO mice, as determined by immunohistochemistry. The expression levels of HIF1α, VEGF, runt‑related transcription factor 2, osteocalcin and alkaline phosphatase were also decreased in PTHKO mice, and fracture healing was delayed. In conclusion, lack of endogenous PTH may reduce VEGF expression in BMSC‑derived osteoblasts by downregulating the activity of the PKA/pAKT/HIF1α/VEGF pathway, thus affecting endochondral bone formation by causing a reduction in angiogenesis and osteogenesis, ultimately leading to delayed fracture healing.

  11. Dispersion of repolarization and refractoriness are determinants of arrhythmia phenotype in transgenic mice with long QT.

    Science.gov (United States)

    London, Barry; Baker, Linda C; Petkova-Kirova, Polina; Nerbonne, Jeanne M; Choi, Bum-Rak; Salama, Guy

    2007-01-01

    Enhanced dispersion of repolarization (DR) and refractoriness may be a unifying mechanism central to arrhythmia genesis in the long QT (LQT) syndrome. The role of DR in promoting arrhythmias was investigated in several strains of molecularly engineered mice: (a) Kv4.2 dominant negative transgenic (Kv4.2DN) that lacks the fast component of the transient outward current, I(to,f), have action potential (AP) and QT prolongation, but no spontaneous arrhythmias, (b) Kv1.4 targeted mice (Kv1.4-/-) that lack the slow component of I(to) (I(to,s)), have no QT prolongation and no spontaneous arrhythmias, and (c) double transgenic (Kv4.2DN x Kv1.4-/-) mice that lack both I(to,f) and I(to,s), have AP and QT prolongation, and spontaneous ventricular tachyarrhythmias. Hearts were perfused, stained with di-4-ANEPPS and optically mapped. Activation patterns and conduction velocities were similar between the strains but AP duration at 75% recovery (APD75) was longer in Kv4.2DN (28.0 +/- 2.5 ms, P mice than controls (20.3 +/- 1.0 ms, n = 5). Dispersion of refractoriness between apex and base was markedly reduced in Kv4.2DN (0.3 +/- 0.5 ms, n = 6, P mice compared with controls (10 +/- 2 ms, n = 5). A premature pulse elicited ventricular tachycardia (VT) in Kv1.4-/- (n = 4/5) and Kv4.2DN x Kv1.4-/- hearts (n = 5/5) but not Kv4.2DN hearts (n = 0/6). Voltage-clamp recordings showed that I(to,f) was 30% greater in myocytes from the apex than base which may account for the absence of DR in Kv4.2DN mice. Thus, dispersion of repolarization (DR) appears to be an important determinant of arrhythmia vulnerability.

  12. Metabolic characteristics of long-lived mice

    Directory of Open Access Journals (Sweden)

    Andrzej eBartke

    2012-12-01

    Full Text Available Genetic suppression of insulin/insulin-like growth factor signaling (IIS can extend longevity in worms, insects, and mammals. In laboratory mice, mutations with the greatest, most consistent, and best documented positive impact on lifespan are those that disrupt growth hormone (GH release or actions. These mutations lead to major alterations in IIS but also have a variety of effects that are not directly related to the actions of insulin or insulin-like growth factor (IGF-1. Long-lived GH-resistant GHRKO mice with targeted disruption of the GH receptor gene, as well as Ames dwarf (Prop1df and Snell dwarf (Pit1dw mice lacking GH (along with prolactin and TSH, are diminutive in size and have major alterations in body composition and metabolic parameters including increased subcutaneous adiposity, increased relative brain weight, small liver, hypoinsulinemia, mild hypoglycemia, increased adiponectin levels and insulin sensitivity, and reduced serum lipids. Body temperature is reduced in Ames, Snell, and female GHRKO mice. Indirect calorimetry revealed that both Ames dwarf and GHRKO mice utilize more oxygen per gram (g of body weight than sex- and age-matched normal animals from the same strain. They also have reduced respiratory quotient (RQ, implying greater reliance on fats, as opposed to carbohydrates, as an energy source. Differences in oxygen consumption (VO2 were seen in animals fed or fasted during the measurements as well as in animals that had been exposed to 30% calorie restriction or every-other-day feeding. However, at the thermoneutral temperature of 30°C, VO2 did not differ between GHRKO and normal mice. Thus, the increased metabolic rate of the GHRKO mice, at a standard animal room temperature of 23°C, is apparently related to increased energy demands for thermoregulation in these diminutive animals. We suspect that increased oxidative metabolism combined with enhanced fatty acid oxidation contribute to the extended longevity of

  13. Entrainment to feeding but not to light: circadian phenotype of VPAC2 receptor-null mice.

    Science.gov (United States)

    Sheward, W John; Maywood, Elizabeth S; French, Karen L; Horn, Jacqueline M; Hastings, Michael H; Seckl, Jonathan R; Holmes, Megan C; Harmar, Anthony J

    2007-04-18

    The master clock driving mammalian circadian rhythms is located in the suprachiasmatic nuclei (SCN) of the hypothalamus and entrained by daily light/dark cycles. SCN lesions abolish circadian rhythms of behavior and result in a loss of synchronized circadian rhythms of clock gene expression in peripheral organs (e.g., the liver) and of hormone secretion (e.g., corticosterone). We examined rhythms of behavior, hepatic clock gene expression, and corticosterone secretion in VPAC2 receptor-null (Vipr2-/-) mice, which lack a functional SCN clock. Unexpectedly, although Vipr2-/- mice lacked robust circadian rhythms of wheel-running activity and corticosterone secretion, hepatic clock gene expression was strongly rhythmic, but advanced in phase compared with that in wild-type mice. The timing of food availability is thought to be an important entrainment signal for circadian clocks outside the SCN. Vipr2-/- mice consumed food significantly earlier in the 24 h cycle than wild-type mice, consistent with the observed timing of peripheral rhythms of circadian gene expression. When restricted to feeding only during the daytime (RF), mice develop rhythms of activity and of corticosterone secretion in anticipation of feeding time, thought to be driven by a food-entrainable circadian oscillator, located outside the SCN. Under RF, mice of both genotypes developed food-anticipatory rhythms of activity and corticosterone secretion, and hepatic gene expression rhythms also became synchronized to the RF stimulus. Thus, food intake is an effective zeitgeber capable of coordinating circadian rhythms of behavior, peripheral clock gene expression, and hormone secretion, even in the absence of a functional SCN clock.

  14. Spatial Frequency Selectivity Is Impaired in Dopamine D2 Receptor Knockout Mice

    Science.gov (United States)

    Souza, Bruno Oliveira Ferreira; Abou Rjeili, Mira; Quintana, Clémentine; Beaulieu, Jean M.; Casanova, Christian

    2018-01-01

    Dopamine is a neurotransmitter implicated in several brain functions, including vision. In the present study, we investigated the impacts of the lack of D2 dopamine receptors on the structure and function of the primary visual cortex (V1) of D2-KO mice using optical imaging of intrinsic signals. Retinotopic maps were generated in order to measure anatomo-functional parameters such as V1 shape, cortical magnification factor, scatter, and ocular dominance. Contrast sensitivity and spatial frequency selectivity (SF) functions were computed from responses to drifting gratings. When compared to control mice, none of the parameters of the retinotopic maps were affected by D2 receptor loss of function. While the contrast sensitivity function of D2-KO mice did not differ from their wild-type counterparts, SF selectivity function was significantly affected as the optimal SF and the high cut-off frequency (p D2-KO than in WT mice. These findings show that the lack of function of D2 dopamine receptors had no influence on cortical structure whereas it had a significant impact on the spatial frequency selectivity and high cut-off. Taken together, our results suggest that D2 receptors play a specific role on the processing of spatial features in early visual cortex while they do not seem to participate in its development. PMID:29379422

  15. Extraneural manifestations of prion infection in GPI-anchorless transgenic mice

    International Nuclear Information System (INIS)

    Lee, Andrew M.; Paulsson, Johan F.; Cruite, Justin; Andaya, Abegail A.; Trifilo, Matthew J.; Oldstone, Michael B.A.

    2011-01-01

    Earlier studies indicated that transgenic (tg) mice engineered to express prion protein (PrP) lacking the glycophosphatidylinositol (GPI -/- ) membrane anchor formed abnormal proteinase-resistant prion (PrPsc) amyloid deposits in their brains and hearts when infected with the RML strain of murine scrapie. In contrast, RML scrapie infection of normal mice with a GPI-anchored PrP did not deposit amyloid with PrPsc in the brain or the heart. Here we report that scrapie-infected GPI -/- PrP tg mice also deposit PrP and transmissible infectious material in the gut, kidneys, and islets of Langerhans. Similar to previously reported amyloid deposits in the brain and heart, amyloid deposits were found in the gut; however, no amyloid deposited in the islets. By high-resolution electron microscopy, we show PrP is located primarily in α cells and also β cells. Islets contain abundant insulin and there is no abnormality in glucose metabolism in infected GPI -/- PrP tg mice.

  16. Targeted Deletion of Kynurenine 3-Monooxygenase in Mice

    Science.gov (United States)

    Giorgini, Flaviano; Huang, Shao-Yi; Sathyasaikumar, Korrapati V.; Notarangelo, Francesca M.; Thomas, Marian A. R.; Tararina, Margarita; Wu, Hui-Qiu; Schwarcz, Robert; Muchowski, Paul J.

    2013-01-01

    Kynurenine 3-monooxygenase (KMO), a pivotal enzyme in the kynurenine pathway (KP) of tryptophan degradation, has been suggested to play a major role in physiological and pathological events involving bioactive KP metabolites. To explore this role in greater detail, we generated mice with a targeted genetic disruption of Kmo and present here the first biochemical and neurochemical characterization of these mutant animals. Kmo−/− mice lacked KMO activity but showed no obvious abnormalities in the activity of four additional KP enzymes tested. As expected, Kmo−/− mice showed substantial reductions in the levels of its enzymatic product, 3-hydroxykynurenine, in liver, brain, and plasma. Compared with wild-type animals, the levels of the downstream metabolite quinolinic acid were also greatly decreased in liver and plasma of the mutant mice but surprisingly were only slightly reduced (by ∼20%) in the brain. The levels of three other KP metabolites: kynurenine, kynurenic acid, and anthranilic acid, were substantially, but differentially, elevated in the liver, brain, and plasma of Kmo−/− mice, whereas the liver and brain content of the major end product of the enzymatic cascade, NAD+, did not differ between Kmo−/− and wild-type animals. When assessed by in vivo microdialysis, extracellular kynurenic acid levels were found to be significantly elevated in the brains of Kmo−/− mice. Taken together, these results provide further evidence that KMO plays a key regulatory role in the KP and indicate that Kmo−/− mice will be useful for studying tissue-specific functions of individual KP metabolites in health and disease. PMID:24189070

  17. p21{sup WAF1/Cip1/Sdi1} knockout mice respond to doxorubicin with reduced cardiotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Terrand, Jerome; Xu, Beibei; Morrissy, Steve; Dinh, Thai Nho [Department of Pharmacology,College of Medicine, University of Arizona, 1501 N. Campbell Ave, Tucson, AZ 85724 (United States); Williams, Stuart [Biomedical Engineering Program, College of Medicine, University of Arizona, 1501 N. Campbell Ave, Tucson, AZ 85724 (United States); Chen, Qin M., E-mail: qchen@email.arizona.edu [Department of Pharmacology,College of Medicine, University of Arizona, 1501 N. Campbell Ave, Tucson, AZ 85724 (United States)

    2011-11-15

    Doxorubicin (Dox) is an antineoplastic agent that can cause cardiomyopathy in humans and experimental animals. As an inducer of reactive oxygen species and a DNA damaging agent, Dox causes elevated expression of p21{sup WAF1/Cip1/Sdi1} (p21) gene. Elevated levels of p21 mRNA and p21 protein have been detected in the myocardium of mice following Dox treatment. With chronic treatment of Dox, wild type (WT) animals develop cardiomyopathy evidenced by elongated nuclei, mitochondrial swelling, myofilamental disarray, reduced cardiac output, reduced ejection fraction, reduced left ventricular contractility, and elevated expression of ANF gene. In contrast, p21 knockout (p21KO) mice did not show significant changes in the same parameters in response to Dox treatment. In an effort to understand the mechanism of the resistance against Dox induced cardiomyopathy, we measured levels of antioxidant enzymes and found that p21KO mice did not contain elevated basal or inducible levels of glutathione peroxidase and catalase. Measurements of 6 circulating cytokines indicated elevation of IL-6, IL-12, IFN{gamma} and TNF{alpha} in Dox treated WT mice but not p21KO mice. Dox induced elevation of IL-6 mRNA was detected in the myocardium of WT mice but not p21KO mice. While the mechanism of the resistance against Dox induced cardiomyopathy remains unclear, lack of inflammatory response may contribute to the observed cardiac protection in p21KO mice. -- Highlights: Black-Right-Pointing-Pointer Doxorubicin induces p21 elevation in the myocardium. Black-Right-Pointing-Pointer Doxorubicin causes dilated cardiomyopathy in wild type mice. Black-Right-Pointing-Pointer p21 Knockout mice are resistant against doxorubicin induced cardiomyopathy. Black-Right-Pointing-Pointer Lack of inflammatory response correlates with the resistance in p21 knockout mice.

  18. Increased infectivity of anchorless mouse scrapie prions in transgenic mice overexpressing human prion protein.

    Science.gov (United States)

    Race, Brent; Phillips, Katie; Meade-White, Kimberly; Striebel, James; Chesebro, Bruce

    2015-06-01

    Prion protein (PrP) is found in all mammals, mostly as a glycoprotein anchored to the plasma membrane by a C-terminal glycosylphosphatidylinositol (GPI) linkage. Following prion infection, host protease-sensitive prion protein (PrPsen or PrPC) is converted into an abnormal, disease-associated, protease-resistant form (PrPres). Biochemical characteristics, such as the PrP amino acid sequence, and posttranslational modifications, such as glycosylation and GPI anchoring, can affect the transmissibility of prions as well as the biochemical properties of the PrPres generated. Previous in vivo studies on the effects of GPI anchoring on prion infectivity have not examined cross-species transmission. In this study, we tested the effect of lack of GPI anchoring on a species barrier model using mice expressing human PrP. In this model, anchorless 22L prions derived from tg44 mice were more infectious than 22L prions derived from C57BL/10 mice when tested in tg66 transgenic mice, which expressed wild-type anchored human PrP at 8- to 16-fold above normal. Thus, the lack of the GPI anchor on the PrPres from tg44 mice appeared to reduce the effect of the mouse-human PrP species barrier. In contrast, neither source of prions induced disease in tgRM transgenic mice, which expressed human PrP at 2- to 4-fold above normal. Prion protein (PrP) is found in all mammals, usually attached to cells by an anchor molecule called GPI. Following prion infection, PrP is converted into a disease-associated form (PrPres). While most prion diseases are species specific, this finding is not consistent, and species barriers differ in strength. The amino acid sequence of PrP varies among species, and this variability affects prion species barriers. However, other PrP modifications, including glycosylation and GPI anchoring, may also influence cross-species infectivity. We studied the effect of PrP GPI anchoring using a mouse-to-human species barrier model. Experiments showed that prions produced by

  19. Impaired performance of skeletal muscle in alpha-glucosidase knockout mice

    NARCIS (Netherlands)

    Hesselink, R.P; Gorselink, M.; Schaart, G.; Wagenmakers, A.J.M.; Kamphoven, G.; Reuser, A.J.J.; Vusse, van der G.J.; Drost, M.R.

    2002-01-01

    Glycogen storage disease type II (GSD II) is an inherited progressive muscle disease in which lack of functional acid -glucosidase (AGLU) results in lysosomal accumulation of glycogen. We report on the impact of a null mutation of the acid -glucosidase gene (AGLU-/-) in mice on the force production

  20. INTERACTION BETWEEN DELTA OPIOID RECEPTORS AND BENZODIAZEPINES IN CO2- INDUCED RESPIRATORY RESPONSES IN MICE

    Science.gov (United States)

    Borkowski, Anne H.; Barnes, Dylan C.; Blanchette, Derek R.; Castellanos, F. Xavier; Klein, Donald F.; Wilson, Donald A.

    2011-01-01

    The false-suffocation hypothesis of panic disorder (Klein, 1993) suggested δ-opioid receptors as a possible source of the respiratory dysfunction manifested in panic attacks occurring in panic disorder (Preter and Klein, 2008). This study sought to determine if a lack of δ-opioid receptors in a mouse model affects respiratory response to elevated CO2, and whether the response is modulated by benzodiazepines, which are widely used to treat panic disorder. In a whole-body plethysmograph, respiratory responses to 5% CO2 were compared between δ-opioid receptor knockout mice and wild-type mice after saline, diazepam (1 mg/kg), and alprazolam (0.3 mg/kg) injection. The results show that lack of δ-opioid receptors does not affect normal response to elevated CO2, but does prevent benzodiazepines from modulating that response. Thus, in the presence of benzodiazepine agonists, respiratory responses to elevated CO2 were enhanced in δ-opioid receptor knockout mice compared to wild-type mice. This suggests an interplay between benzodiazepine receptors and δ-opioid receptors in regulating the respiratory effects of elevated CO2, which might be related to CO2 induced panic. PMID:21561601

  1. CD36 deficiency increases insulin sensitivity in muscle, but induces insulin resistance in the liver in mice

    NARCIS (Netherlands)

    Goudriaan, J.R.; Dahlmans, V.E.H.; Teusink, B.; Ouwens, D.M.; Febbraio, M.; Maassen, J.A.; Romijn, J.A.; Havekes, L.M.; Voshol, P.J.

    2003-01-01

    CD36 (fatty acid translocase) is involved in high-affinity peripheral fatty acid uptake. Mice lacking CD36 exhibit increased plasma free fatty acid and triglyceride (TG) levels and decreased glucose levels. Studies in spontaneous hypertensive rats lacking functional CD36 link CD36 to the

  2. Forced expression of laminin beta1 in podocytes prevents nephrotic syndrome in mice lacking laminin beta2, a model for Pierson syndrome.

    Science.gov (United States)

    Suh, Jung Hee; Jarad, George; VanDeVoorde, Rene G; Miner, Jeffrey H

    2011-09-13

    Pierson syndrome is a congenital nephrotic syndrome with ocular and neurological defects caused by mutations in LAMB2, the gene encoding the basement membrane protein laminin β2 (Lamβ2). It is the kidney glomerular basement membrane (GBM) that is defective in Pierson syndrome, as Lamβ2 is a component of laminin-521 (LM-521; α5β2γ1), the major laminin in the mature GBM. In both Pierson syndrome and the Lamb2(-/-) mouse model for this disease, laminin β1 (Lamβ1), a structurally similar homolog of Lamβ2, is marginally increased in the GBM, but it fails to fully compensate for the loss of Lamβ2, leading to the filtration barrier defects and nephrotic syndrome. Here we generated several lines of Lamβ1 transgenic mice and used them to show that podocyte-specific Lamβ1 expression in Lamb2(-/-) mice abrogates the development of nephrotic syndrome, correlating with a greatly extended lifespan. In addition, the more Lamβ1 was expressed, the less urinary albumin was excreted. Transgenic Lamβ1 expression increased the level of Lamα5 in the GBM of rescued mice, consistent with the desired increased deposition of laminin-511 (α5β1γ1) trimers. Ultrastructural analysis revealed occasional knob-like subepithelial GBM thickening but intact podocyte foot processes in aged rescued mice. These results suggest the possibility that up-regulation of LAMB1 in podocytes, should it become achievable, would likely lessen the severity of nephrotic syndrome in patients carrying LAMB2 mutations.

  3. CDKL5 deficiency entails sleep apneas in mice.

    Science.gov (United States)

    Lo Martire, Viviana; Alvente, Sara; Bastianini, Stefano; Berteotti, Chiara; Silvani, Alessandro; Valli, Alice; Viggiano, Rocchina; Ciani, Elisabetta; Zoccoli, Giovanna

    2017-08-01

    A recently discovered neurodevelopmental disorder caused by the mutation of the cyclin-dependent kinase-like 5 gene (CDKL5) entails complex autistic-like behaviours similar to Rett syndrome, but its impact upon physiological functions remains largely unexplored. Sleep-disordered breathing is common and potentially life-threatening in patients with Rett syndrome; however, evidence is limited in children with CDKL5 disorder, and is lacking altogether in adults. The aim of this study was to test whether the breathing pattern during sleep differs between adult Cdkl5 knockout (Cdkl5-KO) and wild-type (WT) mice. Using whole-body plethysmography, sleep and breathing were recorded non-invasively for 8 h during the light period. Sleep apneas occurred more frequently in Cdkl5-KO than in WT mice. A receiver operating characteristic (ROC) analysis discriminated Cdkl5-KO significantly from WT mice based on sleep apnea occurrence. These data demonstrate that sleep apneas are a core feature of CDKL5 disorder and a respiratory biomarker of CDKL5 deficiency in mice, and suggest that sleep-disordered breathing should be evaluated routinely in CDKL5 patients. © 2017 European Sleep Research Society.

  4. Increased Alzheimer's disease-like pathology in the APP/ PS1ΔE9 mouse model lacking Nrf2 through modulation of autophagy.

    Science.gov (United States)

    Joshi, Gururaj; Gan, Kok Ann; Johnson, Delinda A; Johnson, Jeffrey A

    2015-02-01

    The presence of senile plaques is one of the major pathologic hallmarks of the brain with Alzheimer's disease (AD). The plaques predominantly contain insoluble amyloid β-peptide, a cleavage product of the larger amyloid precursor protein (APP). Two enzymes, named β and γ secretase, generate the neurotoxic amyloid-β peptide from APP. Mature APP is also turned over endogenously by autophagy, more specifically by the endosomal-lysosomal pathway. A defective lysosomal system is known to be pathogenic in AD. Modulation of NF-E2 related factor 2 (Nrf2) has been shown in several neurodegenerative disorders, and Nrf2 has become a potential therapeutic target for various neurodegenerative disorders, including AD, Parkinson's disease, and amyotrophic lateral sclerosis. In the current study, we explored the effect of genetic ablation of Nrf2 on APP/Aβ processing and/or aggregation as well as changes in autophagic dysfunction in APP/PS1 mice. There was a significant increase in inflammatory response in APP/PS1 mice lacking Nrf2. This was accompanied by increased intracellular levels of APP, Aβ (1-42), and Aβ (1-40), without a change total full-length APP. There was a shift of APP and Aβ into the insoluble fraction, as well as increased poly-ubiquitin conjugated proteins in mice lacking Nrf2. APP/PS1-mediated autophagic dysfunction is also enhanced in Nrf2-deficient mice. Finally, neurons in the APP/PS1/Nrf2-/- mice had increased accumulation of multivesicular bodies, endosomes, and lysosomes. These outcomes provide a better understanding of the role of Nrf2 in modulating autophagy in an AD mouse model and may help design better Nrf2 targeted therapeutics that could be efficacious in the treatment of AD. Published by Elsevier Inc.

  5. Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

    Directory of Open Access Journals (Sweden)

    Mark A Little

    Full Text Available Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3 antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener's granulomatosis. Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system. Chimeric mice were generated by injecting human haematopoietic stem cells into irradiated NOD-scid-IL2Rγ⁻/⁻ mice. Matched chimera mice were treated with human IgG from patients with: anti-PR3 positive renal and lung vasculitis; patients with non-vasculitic renal disease; or healthy controls. Six-days later, 39% of anti-PR3 treated mice had haematuria, compared with none of controls. There was punctate bleeding on the surface of lungs of anti-PR3 treated animals, with histological evidence of vasculitis and haemorrhage. Anti-PR3 treated mice had mild pauci-immune proliferative glomerulonephritis, with infiltration of human and mouse leukocytes. In 3 mice (17% more severe glomerular injury was present. There were no glomerular changes in controls. Human IgG from patients with anti-PR3 autoantibodies is therefore pathogenic. This model of anti-PR3 antibody-mediated vasculitis may be useful in dissecting mechanisms of microvascular injury.

  6. Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

    LENUS (Irish Health Repository)

    Little, Mark A

    2012-01-01

    Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3) antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener\\'s granulomatosis). Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system. Chimeric mice were generated by injecting human haematopoietic stem cells into irradiated NOD-scid-IL2Rγ⁻\\/⁻ mice. Matched chimera mice were treated with human IgG from patients with: anti-PR3 positive renal and lung vasculitis; patients with non-vasculitic renal disease; or healthy controls. Six-days later, 39% of anti-PR3 treated mice had haematuria, compared with none of controls. There was punctate bleeding on the surface of lungs of anti-PR3 treated animals, with histological evidence of vasculitis and haemorrhage. Anti-PR3 treated mice had mild pauci-immune proliferative glomerulonephritis, with infiltration of human and mouse leukocytes. In 3 mice (17%) more severe glomerular injury was present. There were no glomerular changes in controls. Human IgG from patients with anti-PR3 autoantibodies is therefore pathogenic. This model of anti-PR3 antibody-mediated vasculitis may be useful in dissecting mechanisms of microvascular injury.

  7. Impaired Muscle Regeneration in Ob/ob and Db/db Mice

    Directory of Open Access Journals (Sweden)

    Mai-Huong Nguyen

    2011-01-01

    Full Text Available In obesity and type 2 diabetes, efficient skeletal muscle repair following injury may be required, not only for restoring muscle structure and function, but also for maintaining exercise capacity and insulin sensitivity. The hypothesis of this study was that muscle regeneration would be impaired in ob/ob and db/db mice, which are common mouse models of obesity and type 2 diabetes. Muscle injury was produced by cardiotoxin injection, and regeneration was assessed by morphological and immunostaining techniques. Muscle regeneration was delayed in ob/ob and db/db mice, but not in a less severe model of insulin resistance – feeding a high-fat diet to wild-type mice. Angiogenesis, cell proliferation, and myoblast accumulation were also impaired in ob/ob and db/db mice, but not the high-fat diet mice. The impairments in muscle regeneration were associated with impaired macrophage accumulation; macrophages have been shown previously to be required for efficient muscle regeneration. Impaired regeneration in ob/ob and db/db mice could be due partly to the lack of leptin signaling, since leptin is expressed both in damaged muscle and in cultured muscle cells. In summary, impaired muscle regeneration in ob/ob and db/db mice was associated with reduced macrophage accumulation, angiogenesis, and myoblast activity, and could have implications for insulin sensitivity in the skeletal muscle of obese and type 2 diabetic patients.

  8. Altered gene expression in pulmonary tissue of tryptophan hydroxylase-1 knockout mice: implications for pulmonary arterial hypertension.

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    Richard B Rothman

    Full Text Available The use of fenfluramines can increase the risk of developing pulmonary arterial hypertension (PAH in humans, but the mechanisms responsible are unresolved. A recent study reported that female mice lacking the gene for tryptophan hydroxylase-1 (Tph1(-/- mice were protected from PAH caused by chronic dexfenfluramine, suggesting a pivotal role for peripheral serotonin (5-HT in the disease process. Here we tested two alternative hypotheses which might explain the lack of dexfenfluramine-induced PAH in Tph1(-/- mice. We postulated that: 1 Tph1(-/- mice express lower levels of pulmonary 5-HT transporter (SERT when compared to wild-type controls, and 2 Tph1(-/- mice display adaptive changes in the expression of non-serotonergic pulmonary genes which are implicated in PAH. SERT was measured using radioligand binding methods, whereas gene expression was measured using microarrays followed by quantitative real time PCR (qRT-PCR. Contrary to our first hypothesis, the number of pulmonary SERT sites was modestly up-regulated in female Tph1(-/- mice. The expression of 51 distinct genes was significantly altered in the lungs of female Tph1(-/- mice. Consistent with our second hypothesis, qRT-PCR confirmed that at least three genes implicated in the pathogenesis of PAH were markedly up-regulated: Has2, Hapln3 and Retlna. The finding that female Tph1(-/- mice are protected from dexfenfluramine-induced PAH could be related to compensatory changes in pulmonary gene expression, in addition to reductions in peripheral 5-HT. These observations emphasize the intrinsic limitation of interpreting data from studies conducted in transgenic mice that are not fully characterized.

  9. Immunization against Leishmania major infection using LACK- and IL-12-expressing Lactococcus lactis induces delay in footpad swelling.

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    Felix Hugentobler

    Full Text Available BACKGROUND: Leishmania is a mammalian parasite affecting over 12 million individuals worldwide. Current treatments are expensive, cause severe side effects, and emerging drug resistance has been reported. Vaccination is the most cost-effective means to control infectious disease but currently there is no vaccine available against Leishmaniasis. Lactococcus lactis is a non-pathogenic, non-colonizing Gram-positive lactic acid bacterium commonly used in the dairy industry. Recently, L. lactis was used to express biologically active molecules including vaccine antigens and cytokines. METHODOLOGY/PRINCIPAL FINDINGS: We report the generation of L. lactis strains expressing the protective Leishmania antigen, LACK, in the cytoplasm, secreted or anchored to the bacterial cell wall. L. lactis was also engineered to secrete biologically active single chain mouse IL-12. Subcutaneous immunization with live L. lactis expressing LACK anchored to the cell wall and L. lactis secreting IL-12 significantly delayed footpad swelling in Leishmania major infected BALB/c mice. The delay in footpad swelling correlated with a significant reduction of parasite burden in immunized animals compared to control groups. Immunization with these two L. lactis strains induced antigen-specific multifunctional T(H1 CD4(+ and CD8(+ T cells and a systemic LACK-specific T(H1 immune response. Further, protection in immunized animals correlated with a Leishmania-specific T(H1 immune response post-challenge. L. lactis secreting mouse IL-12 was essential for directing immune responses to LACK towards a protective T(H1 response. CONCLUSIONS/SIGNIFICANCE: This report demonstrates the use of L. lactis as a live vaccine against L. major infection in BALB/c mice. The strains generated in this study provide the basis for the development of an inexpensive and safe vaccine against the human parasite Leishmania.

  10. Immunization against Leishmania major Infection Using LACK- and IL-12-Expressing Lactococcus lactis Induces Delay in Footpad Swelling

    Science.gov (United States)

    Hugentobler, Felix; Yam, Karen K.; Gillard, Joshua; Mahbuba, Raya; Olivier, Martin; Cousineau, Benoit

    2012-01-01

    Background Leishmania is a mammalian parasite affecting over 12 million individuals worldwide. Current treatments are expensive, cause severe side effects, and emerging drug resistance has been reported. Vaccination is the most cost-effective means to control infectious disease but currently there is no vaccine available against Leishmaniasis. Lactococcus lactis is a non-pathogenic, non-colonizing Gram-positive lactic acid bacterium commonly used in the dairy industry. Recently, L. lactis was used to express biologically active molecules including vaccine antigens and cytokines. Methodology/Principal findings We report the generation of L. lactis strains expressing the protective Leishmania antigen, LACK, in the cytoplasm, secreted or anchored to the bacterial cell wall. L. lactis was also engineered to secrete biologically active single chain mouse IL-12. Subcutaneous immunization with live L. lactis expressing LACK anchored to the cell wall and L. lactis secreting IL-12 significantly delayed footpad swelling in Leishmania major infected BALB/c mice. The delay in footpad swelling correlated with a significant reduction of parasite burden in immunized animals compared to control groups. Immunization with these two L. lactis strains induced antigen-specific multifunctional TH1 CD4+ and CD8+ T cells and a systemic LACK-specific TH1 immune response. Further, protection in immunized animals correlated with a Leishmania-specific TH1 immune response post-challenge. L. lactis secreting mouse IL-12 was essential for directing immune responses to LACK towards a protective TH1 response. Conclusions/Significance This report demonstrates the use of L. lactis as a live vaccine against L. major infection in BALB/c mice. The strains generated in this study provide the basis for the development of an inexpensive and safe vaccine against the human parasite Leishmania. PMID:22348031

  11. Impaired growth and neurological abnormalities in branched-chain α-keto acid dehydrogenase kinase-deficient mice

    Science.gov (United States)

    Joshi, Mandar A.; Jeoung, Nam Ho; Obayashi, Mariko; Hattab, Eyas M.; Brocken, Eric G.; Liechty, Edward A.; Kubek, Michael J.; Vattem, Krishna M.; Wek, Ronald C.; Harris, Robert A.

    2006-01-01

    The BCKDH (branched-chain α-keto acid dehydrogenase complex) catalyses the rate-limiting step in the oxidation of BCAAs (branched-chain amino acids). Activity of the complex is regulated by a specific kinase, BDK (BCKDH kinase), which causes inactivation, and a phosphatase, BDP (BCKDH phosphatase), which causes activation. In the present study, the effect of the disruption of the BDK gene on growth and development of mice was investigated. BCKDH activity was much greater in most tissues of BDK−/− mice. This occurred in part because the E1 component of the complex cannot be phosphorylated due to the absence of BDK and also because greater than normal amounts of the E1 component were present in tissues of BDK−/− mice. Lack of control of BCKDH activity resulted in markedly lower blood and tissue levels of the BCAAs in BDK−/− mice. At 12 weeks of age, BDK−/− mice were 15% smaller than wild-type mice and their fur lacked normal lustre. Brain, muscle and adipose tissue weights were reduced, whereas weights of the liver and kidney were greater. Neurological abnormalities were apparent by hind limb flexion throughout life and epileptic seizures after 6–7 months of age. Inhibition of protein synthesis in the brain due to hyperphosphorylation of eIF2α (eukaryotic translation initiation factor 2α) might contribute to the neurological abnormalities seen in BDK−/− mice. BDK−/− mice show significant improvement in growth and appearance when fed a high protein diet, suggesting that higher amounts of dietary BCAA can partially compensate for increased oxidation in BDK−/− mice. Disruption of the BDK gene establishes that regulation of BCKDH by phosphorylation is critically important for the regulation of oxidative disposal of BCAAs. The phenotype of the BDK−/− mice demonstrates the importance of tight regulation of oxidative disposal of BCAAs for normal growth and neurological function. PMID:16875466

  12. Elevated sensitivity to diet-induced obesity and insulin resistance in mice lacking 4E-BP1 and 4E-BP2.

    Science.gov (United States)

    Le Bacquer, Olivier; Petroulakis, Emmanuel; Paglialunga, Sabina; Poulin, Francis; Richard, Denis; Cianflone, Katherine; Sonenberg, Nahum

    2007-02-01

    The most common pathology associated with obesity is insulin resistance, which results in the onset of type 2 diabetes mellitus. Several studies have implicated the mammalian target of rapamycin (mTOR) signaling pathway in obesity. Eukaryotic translation initiation factor 4E-binding (eIF4E-binding) proteins (4E-BPs), which repress translation by binding to eIF4E, are downstream effectors of mTOR. We report that the combined disruption of 4E-BP1 and 4E-BP2 in mice increased their sensitivity to diet-induced obesity. Increased adiposity was explained at least in part by accelerated adipogenesis driven by increased expression of CCAAT/enhancer-binding protein delta (C/EBPdelta), C/EBPalpha, and PPARgamma coupled with reduced energy expenditure, reduced lipolysis, and greater fatty acid reesterification in the adipose tissue of 4E-BP1 and 4E-BP2 double KO mice. Increased insulin resistance in 4E-BP1 and 4E-BP2 double KO mice was associated with increased ribosomal protein S6 kinase (S6K) activity and impairment of Akt signaling in muscle, liver, and adipose tissue. These data clearly demonstrate the role of 4E-BPs as a metabolic brake in the development of obesity and reinforce the idea that deregulated mTOR signaling is associated with the development of the metabolic syndrome.

  13. Forced expression of laminin β1 in podocytes prevents nephrotic syndrome in mice lacking laminin β2, a model for Pierson syndrome

    Science.gov (United States)

    Suh, Jung Hee; Jarad, George; VanDeVoorde, Rene G.; Miner, Jeffrey H.

    2011-01-01

    Pierson syndrome is a congenital nephrotic syndrome with ocular and neurological defects caused by mutations in LAMB2, the gene encoding the basement membrane protein laminin β2 (Lamβ2). It is the kidney glomerular basement membrane (GBM) that is defective in Pierson syndrome, as Lamβ2 is a component of laminin-521 (LM-521; α5β2γ1), the major laminin in the mature GBM. In both Pierson syndrome and the Lamb2−/− mouse model for this disease, laminin β1 (Lamβ1), a structurally similar homolog of Lamβ2, is marginally increased in the GBM, but it fails to fully compensate for the loss of Lamβ2, leading to the filtration barrier defects and nephrotic syndrome. Here we generated several lines of Lamβ1 transgenic mice and used them to show that podocyte-specific Lamβ1 expression in Lamb2−/− mice abrogates the development of nephrotic syndrome, correlating with a greatly extended lifespan. In addition, the more Lamβ1 was expressed, the less urinary albumin was excreted. Transgenic Lamβ1 expression increased the level of Lamα5 in the GBM of rescued mice, consistent with the desired increased deposition of laminin-511 (α5β1γ1) trimers. Ultrastructural analysis revealed occasional knob-like subepithelial GBM thickening but intact podocyte foot processes in aged rescued mice. These results suggest the possibility that up-regulation of LAMB1 in podocytes, should it become achievable, would likely lessen the severity of nephrotic syndrome in patients carrying LAMB2 mutations. PMID:21876163

  14. Histidine Decarboxylase Deficiency Prevents Autoimmune Diabetes in NOD Mice

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    Manal Alkan

    2015-01-01

    Full Text Available Recent evidence has highlighted the role of histamine in inflammation. Since this monoamine has also been strongly implicated in the pathogenesis of type-1 diabetes, we assessed its effect in the nonobese diabetic (NOD mouse model. To this end, we used mice (inactivated knocked out for the gene encoding histidine decarboxylase, the unique histamine-forming enzyme, backcrossed on a NOD genetic background. We found that the lack of endogenous histamine in NOD HDC−/− mice decreased the incidence of diabetes in relation to their wild-type counterpart. Whereas the proportion of regulatory T and myeloid-derived suppressive cells was similar in both strains, histamine deficiency was associated with increased levels of immature macrophages, as compared with wild-type NOD mice. Concerning the cytokine pattern, we found a decrease in circulating IL-12 and IFN-γ in HDC−/− mice, while IL-6 or leptin remained unchanged, suggesting that histamine primarily modulates the inflammatory environment. Paradoxically, exogenous histamine given to NOD HDC−/− mice provided also protection against T1D. Our study supports the notion that histamine is involved in the pathogenesis of diabetes, thus providing additional evidence for its role in the regulation of the immune response.

  15. [Anatomy and histology characteristics of lymph node in nude mice].

    Science.gov (United States)

    Sun, R; Gao, B; Guo, C B

    2017-10-18

    To compare the differences of anatomical and histological characteristics of lymph nodes between BALB/c nude mice and BALB/c mice. Firstly, twenty BALB/c nude mice and twenty BALB/c mice were dissected by using a surgical microscope. Secondly, the differences of T cells and B cells at the lymph node were compared by the expressions of CD 3 and CD 20 immunohistochemistry dyes. There were, on average, 23 nodes per mouse contained within the large lymph node assembly in the BALB/c nude mouse. The anatomical features of the lymph node distribution in the nude mice were mainly found in the neck with relatively higher density. There were two lymph nodes both in the submandible lymph nodes group and in the superficial cervical lymph nodes group (the constituent ratios were 95% and 90%, respectively) in the BALB/c nude mice, but there were four lymph nodes (the constituent ratios were 95% and 90%, respectively) in the BALB/c mice. There were significant difference between the BALB/c nude mice and the BALB/c mice. Mostly there were two lymph nodes of deep cervical lymph nodes both in the BALB/c nude mice and the BALB/c mice (the constituent ratios were 95% and 100%, respectively). There were no significant difference between the BALB/c nude mice and the BALB/c mice. We confirmed that the number of CD 3 -positive T lymphocytes in lymph nodes of the nude mice decreased greatly as compared with the BALB/c mice. Expressions of CD3 in T cells were 95% and 100% in the BALB/c nude mice and in the BALB/c mice, respectively. There were significant differences between the BALB/c nude mice and the BALB/c mice. Expressions of CD20 in B cells were 95% and 100% in the BALB/c nude mice and in the BALB/c mice, respectively. There was no significant difference between the BALB/c nude mice and BALB/c mice. The anatomical pictures of lymph node distribution in the nude mouse will be benefit to those who are interested. The anatomical features of the lymph node local higher density in neck of

  16. Double gene deletion reveals the lack of cooperation between PPARα and PPARβ in skeletal muscle

    International Nuclear Information System (INIS)

    Bedu, E.; Desplanches, D.; Pequignot, J.; Bordier, B.; Desvergne, B.

    2007-01-01

    The peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of most of the pathways linked to lipid metabolism. PPARα and PPARβ isotypes are known to regulate muscle fatty acid oxidation and a reciprocal compensation of their function has been proposed. Herein, we investigated muscle contractile and metabolic phenotypes in PPARα-/-, PPARβ-/-, and double PPARα-/- β-/- mice. Heart and soleus muscle analyses show that the deletion of PPARα induces a decrease of the HAD activity (β-oxidation) while soleus contractile phenotype remains unchanged. A PPARβ deletion alone has no effect. However, these mild phenotypes are not due to a reciprocal compensation of PPARβ and PPARα functions since double gene deletion PPARα-PPARβ mostly reproduces the null PPARα-mediated reduced β-oxidation, in addition to a shift from fast to slow fibers. In conclusion, PPARβ is not required for maintaining skeletal muscle metabolic activity and does not compensate the lack of PPARα in PPARα null mice

  17. Female Nur77-deficient mice show increased susceptibility to diet-induced obesity.

    Directory of Open Access Journals (Sweden)

    Sonia Perez-Sieira

    Full Text Available Adipose tissue is essential in the regulation of body weight. The key process in fat catabolism and the provision of energy substrate during times of nutrient deprivation or enhanced energy demand is the hydrolysis of triglycerides and the release of fatty acids and glycerol. Nur77 is a member of the NR4A subfamily of nuclear receptors that plays an important metabolic role, modulating hepatic glucose metabolism and lipolysis in muscle. However, its endogenous role on white adipose tissue, as well as the gender dependency of these mechanisms, remains largely unknown. Male and female wild type and Nur77 deficient mice were fed with a high fat diet (45% calories from fat for 4 months. Mice were analyzed in vivo with the indirect calorimetry system, and tissues were analyzed by real-time PCR and Western blot analysis. Female, but not male Nur77 deficient mice, gained more weight and fat mass when compared to wild type mice fed with high fat diet, which can be explained by decreased energy expenditure. The lack of Nur77 also led to a decreased pHSL/HSL ratio in white adipose tissue and increased expression of CIDEA in brown adipose tissue of female Nur77 deficient mice. Overall, these findings suggest that Nur77 is an important physiological modulator of lipid metabolism in adipose tissue and that there are gender differences in the sensitivity to deletion of the Nur77 signaling. The decreased energy expenditure and the actions of Nur77 on liver, muscle, brown and white adipose tissue contribute to the increased susceptibility to diet-induced obesity in females lacking Nur77.

  18. Neuroanatomy of pars intercerebralis neurons with special reference to their connections with neurons immunoreactive for pigment-dispersing factor in the blow fly Protophormia terraenovae.

    Science.gov (United States)

    Yasuyama, Kouji; Hase, Hiroaki; Shiga, Sakiko

    2015-10-01

    Input regions of pars intercerebralis (PI) neurons are examined by confocal and electron microscopies with special reference to their connections with neurons immunoreactive for pigment-dispersing factor (PDF) in the blow fly, Protophormia terraenovae. PI neurons are a prerequisite for ovarian development under long-day conditions. Backfills from the cardiac recurrent nerve after severance of the posterior lateral tracts labeled thin fibers derived from the PI neurons in the superior medial protocerebrum. These PI fibers were mainly synapsin-negative and postsynaptic to unknown varicose profiles containing dense-core vesicles. Backfilled fibers in the periesophageal neuropils, derived from the PI neurons or neurons with somata in the subesophageal zone, were varicose and some were synapsin-positive. Electron microscopy revealed the presence of both presynaptic and postsynaptic sites in backfilled fibers in the periesophageal neuropils. Many PDF-immunoreactive varicosities were found in the superior medial and lateral protocerebrum and double-labeling showed that 60-88 % of PDF-immunoreactive varicosities were also synapsin-immunoreactive. Double-labeling with the backfills and PDF immunocytochemistry showed that the PI fibers and PDF-immunoreactive varicosities were located close to each other in the superior medial protocerebrum. Results of triple-labeling of PI neurons, PDF-immunoreactive neurons and synapsin-immunoreactive terminals demonstrated that the synapsin-positive PDF-immunoreactive varicosities contacted the PI fibers. These data suggest that PI neurons receive synaptic contacts from PDF-immunoreactive fibers, which are derived from circadian clock neurons, of small ventral lateral neurons (previously called OL2) or posterior dorsal (PD) neurons with somata in the pars lateralis.

  19. Lack of ClC-2 Alleviates High Fat Diet-Induced Insulin Resistance and Non-Alcoholic Fatty Liver Disease

    Directory of Open Access Journals (Sweden)

    Dongxia Fu

    2018-03-01

    Full Text Available Background/Aims: Non-alcoholic fatty liver disease (NAFLD is the most common cause of chronic liver disease. This study aims to investigate whether chloride channel 2 (ClC-2 is involved in high fat diet (HFD-induced NAFLD and possible molecular mechanisms. Methods: ClC-2 expression was liver-specifically downregulated using adeno-associated virus in C57BL/6 mice treated with a chow diet or HFD for 12 weeks. Peripheral blood and liver tissues were collected for biochemical and pathological estimation respectively. Western blotting was applied to detect the protein expressions of lipid synthesis-related enzymes and the phosphorylated level of IRS-1, Akt and mTOR. Results: ClC-2 mRNA level was significantly increased in patients with non-alcoholic steatohepatitis, which positively correlated with the plasma levels of alanine transaminase (ALT, aspartate transaminase (AST and insulin. Knockdown of ClC-2 in liver attenuated HFD-induced weight gain, obesity, hepatocellular ballooning, and liver lipid accumulation and fibrosis, accompanied by reduced plasma free fatty acid (FFA, triglyceride (TG, total cholesterol (TC, ALT, AST, glucose and insulin levels and homeostasis model of insulin resistance (HOMA-IR value. Moreover, HFD-treated mice lacking ClC-2 showed inhibited hepatic lipid accumulation via regulating lipid metabolism through decreasing sterol regulatory element binding protein (SREBP-1c expression and its downstream targeting enzymes such as fatty acid synthase (FAS, HMG-CoA reductase (HMGCR and acetyl-Coenzyme A carboxylase (ACCα. In addition, in vivo and in vitro results demonstrated that ClC-2 downregulation in HFD-treated mice or HepG2 cells increased the sensitivity to insulin via activation of IRS-1/Akt/mTOR signaling pathway. Conclusion: Our present study reveals a critical role of ClC-2 in regulating metabolic diseases. Mice lacking ClC-2 are associated with a remarkably beneficial metabolic phenotype, suggesting that decreasing Cl

  20. Upregulation of B7 molecules (CD80 and CD86) and exacerbated eosinophilic pulmonary inflammatory response in mice lacking the IFN-beta gene

    DEFF Research Database (Denmark)

    Matheu, Victor; Treschow, Alexandra; Navikas, Vaidrius

    2003-01-01

    . OBJECTIVE: We sought to define the differential role of endogenous IFN-beta in controlling the development of allergic inflammation. METHODS: We assessed whether deletion of the gene encoding IFN-beta (IFNB) with knockout mice participated in the development of allergic response in ovalbumin (OVA......BACKGROUND: IFN-beta has been shown to be effective as therapy for multiple sclerosis. Some reports attributed its beneficial effects to the capacity to induce a T(H)2 response. However, other studies have suggested that endogenous type I IFN might downregulate the allergic response in mice...

  1. Regulation of PDGFC signalling and extracellular matrix composition by FREM1 in mice

    Directory of Open Access Journals (Sweden)

    Fenny Wiradjaja

    2013-11-01

    Fras1-related extracellular matrix protein 1 (FREM1 is required for epidermal adhesion during embryogenesis, and mice lacking the gene develop fetal skin blisters and a range of other developmental defects. Mutations in members of the FRAS/FREM gene family cause diseases of the Fraser syndrome spectrum. Embryonic epidermal blistering is also observed in mice lacking PdgfC and its receptor, PDGFRα. In this article, we show that FREM1 binds to PDGFC and that this interaction regulates signalling downstream of PDGFRα. Fibroblasts from Frem1-mutant mice respond to PDGFC stimulation, but with a shorter duration and amplitude than do wild-type cells. Significantly, PDGFC-stimulated expression of the metalloproteinase inhibitor Timp1 is reduced in cells with Frem1 mutations, leading to reduced basement membrane collagen I deposition. These results show that the physical interaction of FREM1 with PDGFC can regulate remodelling of the extracellular matrix downstream of PDGFRα. We propose that loss of FREM1 function promotes epidermal blistering in Fraser syndrome as a consequence of reduced PDGFC activity, in addition to its stabilising role in the basement membrane.

  2. Lipid metabolism and body composition in Gclm(−/−) mice

    International Nuclear Information System (INIS)

    Kendig, Eric L.; Chen, Ying; Krishan, Mansi; Johansson, Elisabet; Schneider, Scott N.; Genter, Mary Beth; Nebert, Daniel W.; Shertzer, Howard G.

    2011-01-01

    In humans and experimental animals, high fat diets (HFD) are associated with risk factors for metabolic diseases, such as excessive weight gain and adiposity, insulin resistance and fatty liver. Mice lacking the glutamate–cysteine ligase modifier subunit gene (Gclm(−/−)) and deficient in glutathione (GSH), are resistant to HFD-mediated weight gain. Herein, we evaluated Gclm-associated regulation of energy metabolism, oxidative stress, and glucose and lipid homeostasis. C57BL/6J Gclm(−/−) mice and littermate wild-type (WT) controls received a normal diet or an HFD for 11 weeks. HFD-fed Gclm(−/−) mice did not display a decreased respiratory quotient, suggesting that they are unable to process lipid for metabolism. Although dietary energy consumption and intestinal lipid absorption were unchanged in Gclm(−/−) mice, feeding these mice an HFD did not produce excess body weight nor fat storage. Gclm(−/−) mice displayed higher basal metabolic rates resulting from higher activities of liver mitochondrial NADH-CoQ oxidoreductase, thus elevating respiration. Although Gclm(−/−) mice exhibited strong systemic and hepatic oxidative stress responses, HFD did not promote glucose intolerance or insulin resistance. Furthermore, HFD-fed Gclm(−/−) mice did not develop fatty liver, likely resulting from very low expression levels of genes encoding lipid metabolizing enzymes. We conclude that Gclm is involved in the regulation of basal metabolic rate and the metabolism of dietary lipid. Although Gclm(−/−) mice display a strong oxidative stress response, they are protected from HFD-induced excessive weight gain and adipose deposition, insulin resistance and steatosis. -- Highlights: ► A high fat diet does not produce body weight and fat gain in Gclm(−/−) mice. ► A high fat diet does not induce steatosis or insulin resistance in Gclm(−/−) mice. ► Gclm(−/−) mice have high basal metabolism and mitochondrial oxygen consumption.

  3. Adrenal and liver in normal and cld/cld mice synthesize and secrete hepatic lipase, but the lipase is inactive in cld/cld mice.

    Science.gov (United States)

    Schultz, C J; Blanchette-Mackie, E J; Scow, R O

    2000-02-01

    Combined lipase deficiency (cld) is a recessive mutation in mice that causes a severe lack of lipoprotein lipase (LPL) and hepatic lipase (HL) activities, hyperlipemia, and death within 3 days after birth. Earlier studies showed that inactive LPL and HL were synthesized by cld/cld tissues and that LPL synthesized by cld/cld brown adipocytes was retained in their ER. We report here a study of HL in liver, adrenal, and plasma of normal newborn and cld/cld mice. Immunofluorescence studies showed HL was present in extracellular space, but not in cells, in liver and adrenal of both normal and cld/cld mice. When protein secretion was blocked with monensin, HL was retained intracellularly in liver cell cultures and in incubated adrenal tissues of both groups of mice. These findings demonstrated that HL was synthesized and secreted by liver and adrenal cells in normal newborn and cld/cld mice. HL activities in liver, adrenal, and plasma in cld/cld mice were very low, cld/cld cells was inactive. Livers of both normal newborn and cld/cld mice synthesized LPL, but the level of LPL activity in cld/cld liver was very low, cld/cld mice, indicating that LPL was synthesized but not secreted by cld/cld liver cells. Immunofluorescent LPL was not found in normal newborn liver cells unless the cells were treated with monensin, thus demonstrating that normal liver cells synthesized and secreted LPL. Livers of both groups of mice contained an unidentified alkaline lipase activity which accounted for 34-54% of alkaline lipase activity in normal and 65% of that in cld/cld livers. Our findings indicate that liver and adrenal cells synthesized and secreted HL in both normal newborn and cld/cld mice, but the lipase was inactive in cld/cld mice. That cld/cld liver cells secreted inactive HL while retaining inactive LPL indicates that these closely related lipases were processed differently.

  4. Germline mutation rates at tandem repeat loci in DNA-repair deficient mice

    International Nuclear Information System (INIS)

    Barber, Ruth C.; Miccoli, Laurent; Buul, Paul P.W. van; Burr, Karen L.-A.; Duyn-Goedhart, Annemarie van; Angulo, Jaime F.; Dubrova, Yuri E.

    2004-01-01

    Mutation rates at two expanded simple tandem repeat (ESTR) loci were studied in the germline of non-exposed and irradiated severe combined immunodeficient (scid) and poly(ADP-ribose) polymerase (PARP-1 -/- ) deficient male mice. Non-exposed scid and PARP -/- male mice showed considerably elevated ESTR mutation rates, far higher than those in wild-type isogenic mice and other inbred strains. The irradiated scid and PARP-1 -/- male mice did not show any detectable increases in their mutation rate, whereas significant ESTR mutation induction was observed in the irradiated wild-type isogenic males. ESTR mutation spectra in the scid and PARP-1 -/- strains did not differ from those in the isogenic wild-type strains. Considering these data and the results of previous studies, we propose that a delay in repair of DNA damage in scid and PARP-1 -/- mice could result in replication fork pausing which, in turn, may affect ESTR mutation rate in the non-irradiated males. The lack of mutation induction in irradiated scid and PARP-1 -/- can be explained by the high cell killing effects of irradiation on the germline of deficient mice

  5. Osteocalcin is necessary and sufficient to maintain muscle mass in older mice

    Directory of Open Access Journals (Sweden)

    Paula Mera

    2016-10-01

    Full Text Available Objective: A decrease in muscle protein turnover and therefore in muscle mass is a hallmark of aging. Because the circulating levels of the bone-derived hormone osteocalcin decline steeply during aging in mice, monkeys and humans we asked here whether this hormone might regulate muscle mass as mice age. Methods: We examined muscle mass and strength in mice lacking osteocalcin (Ocn−/− or its receptor in all cells (Gprc6a−/− or specifically in myofibers (Gprc6aMck−/− as well as in 9 month-old WT mice receiving exogenous osteocalcin for 28 days. We also examined protein synthesis in WT and Gprc6a−/− mouse myotubes treated with osteocalcin. Results: We show that osteocalcin signaling in myofibers is necessary to maintain muscle mass in older mice in part because it promotes protein synthesis in myotubes without affecting protein breakdown. We further show that treatment with exogenous osteocalcin for 28 days is sufficient to increase muscle mass of 9-month-old WT mice. Conclusion: This study uncovers that osteocalcin is necessary and sufficient to prevent age-related muscle loss in mice. Author Video: Author Video Watch what authors say about their articles Keywords: Osteocalcin, Muscle mass, Aging

  6. Aggravated restenosis and atherogenesis in ApoCIII transgenic mice but lack of protection in ApoCIII knockouts: the effect of authentic triglyceride-rich lipoproteins with and without ApoCIII.

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    Li, Haibo; Han, Yingchun; Qi, Rong; Wang, Yuhui; Zhang, Xiaohong; Yu, Maomao; Tang, Yin; Wang, Mengyu; Shu, Ya-Nan; Huang, Wei; Liu, Xinfeng; Rodrigues, Brian; Han, Mei; Liu, George

    2015-09-01

    Previously, our group and others have demonstrated a causative relationship between severe hypertriglyceridaemia and atherogenesis in mice. Furthermore, clinical investigations have shown high levels of plasma Apolipoprotein C-III (ApoCIII) associated with hypertriglyceridaemia and even cardiovascular disease. However, it remains unclear whether ApoCIII affects restenosis in vivo, and whether such an effect is mediated by ApoCIII alone, or in combination with hypertriglyceridaemia. We sought to investigate ApoCIII in restenosis and clarify how smooth muscle cells (SMCs) respond to authentic triglyceride-rich lipoproteins (TRLs) with or without ApoCIII (TRLs ± ApoCIII). ApoCIII transgenic (ApoCIIItg) and knockout (ApoCIII-/-) mice underwent endothelial denudation to model restenosis. Here, ApoCIIItg mice displayed severe hypertriglyceridaemia and increased neointimal formation compared with wild-type (WT) or ApoCIII-/- mice. Furthermore, increased proliferating cell nuclear antigen (PCNA)-positive cells, Mac-3, and vascular cell adhesion protein-1 (VCAM-1) expression, and 4-hydroxynonenal (4HNE) production were found in lesion sites. ApoCIIItg and ApoCIII-/- mice were then crossed to low-density lipoprotein receptor-deficient (Ldlr-/-) mice and fed an atherogenic diet. ApoCIIItg/Ldlr-/- mice had significantly increased atherosclerotic lesions. However, there was no statistical difference in restenosis between ApoCIII-/- and WT mice, and in atherosclerosis between ApoCIII/Ldlr double knockout and Ldlr-/- mice. SMCs were then incubated in vitro with authentic TRLs ± ApoCIII isolated from extreme hypertriglyceridaemia glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1-deficient (GPIHBP1-/-) mice crossed with ApoCIIItg or ApoCIII-/- mice. It was shown that TRLs + ApoCIII promoted SMC proliferation, VCAM-1 expression, and reactive oxygen species (ROS) production, and activated the Akt pathway. Scavenging ROS significantly reduced SMC

  7. Comparative Hair Restorer Efficacy of Medicinal Herb on Nude (Foxn1nu Mice

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    Shahnaz Begum

    2014-01-01

    Full Text Available Eclipta alba (L. Hassk, Asiasarum sieboldii (Miq. F. Maek (Asiasari radix, and Panax ginseng C. A. Mey (red ginseng are traditionally acclaimed for therapeutic properties of various human ailments. Synergistic effect of each standardized plant extract was investigated for hair growth potential on nude mice, as these mutant mice genetically lack hair due to abnormal keratinization. Dried plant samples were ground and extracted by methanol. Topical application was performed on the back of nude mice daily up to completion of two hair growth generations. The hair density and length of Eclipta alba treated mice were increased significantly P>0.001 than control mice. Hair growth area was also distinctly visible in Eclipta alba treated mice. On the other hand, Asiasari radix and Panax ginseng treated mice developing hair loss were recognized from the abortive boundaries of hair coverage. Histomorphometric observation of nude mice skin samples revealed an increase in number of hair follicles (HFs. The presence of follicular keratinocytes was confirmed by BrdU labeling, S-phase cells in HFs. Therefore, Eclipta alba extract and/or phytochemicals strongly displayed incomparability of hair growth promotion activity than others. Thus, the standardized Eclipta alba extract can be used as an effective, alternative, and complementary treatment against hair loss.

  8. Profiling helper T cell subset gene expression in deer mice

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    Hjelle Brian

    2006-08-01

    Full Text Available Abstract Background Deer mice (Peromyscus maniculatus are the most common mammals in North America and are reservoirs for several zoonotic agents, including Sin Nombre virus (SNV, the principal etiologic agent of hantavirus cardiopulmonary syndrome (HCPS in North America. Unlike human HCPS patients, SNV-infected deer mice show no overt pathological symptoms, despite the presence of virus in the lungs. A neutralizing IgG antibody response occurs, but the virus establishes a persistent infection. Limitations of detailed analysis of deer mouse immune responses to SNV are the lack of reagents and methods for evaluating such responses. Results We developed real-time PCR-based detection assays for several immune-related transcription factor and cytokine genes from deer mice that permit the profiling of CD4+ helper T cells, including markers of Th1 cells (T-bet, STAT4, IFNγ, TNF, LT, Th2 cells (GATA-3, STAT6, IL-4, IL-5 and regulatory T cells (Fox-p3, IL-10, TGFβ1. These assays compare the expression of in vitro antigen-stimulated and unstimulated T cells from individual deer mice. Conclusion We developed molecular methods for profiling immune gene expression in deer mice, including a multiplexed real-time PCR assay for assessing expression of several cytokine and transcription factor genes. These assays should be useful for characterizing the immune responses of experimentally- and naturally-infected deer mice.

  9. The lack of therapeutic effects in mice of the combined gamma-irradiated Mycobacterium leprae and viable BCG against Mycobacterium leprae infection

    International Nuclear Information System (INIS)

    Saito, Hajime; Tomioka, Haruaki; Kitagawa, Toshiyuki

    1985-01-01

    Gamma-irradiated M. leprae in combination with BCG given once biweekly to mice from 2 weeks for up to 187 days after infection with M. leprae caused no significant growth inhibition of M. leprae, at the site of the infection. (author)

  10. Hydroxyurea treatment inhibits proliferation of Cryptococcus neoformans in mice

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    Kaushlendra eTripathi

    2012-05-01

    Full Text Available The fungal pathogen Cryptococcus neoformans (Cn is a serious threat to immunocompromised individuals, especially for HIV patients who develop meningoencephalitis. For effective cryptococcal treatment, novel antifungal drugs or innovative combination therapies are needed. Recently, sphingolipids have emerged as important bioactive molecules in the regulation of microbial pathogenesis. Previously we reported that the sphingolipid pathway gene, ISC1, which is responsible for ceramide production, is a major virulence factor in Cn infection. Here we report our studies of the role of ISC1 during genotoxic stress induced by the antineoplastic hydroxyurea (HU and methylmethane sulfonate (MMS, which affect DNA replication and genome integrity. We observed that Cn cells lacking ISC1 are highly sensitive to HU and MMS in a rich culture medium. HU affected cell division of Cn cells lacking the ISC1 gene, resulting in cell clusters. Cn ISC1, when expressed in a Saccharomyces cerevisiae (Sc strain lacking its own ISC1 gene, restored HU resistance. In macrophage-like cells, although HU affected the proliferation of WT Cn cells by 50% at the concentration tested, HU completely inhibited Cn isc1-delta cell proliferation. Interestingly, our preliminary data show that mice infected with WT or Cn isc1-delta cells and subsequently treated with HU had longer lifespans than untreated, infected control mice. Our work suggests that the sphingolipid pathway gene, ISC1, is a likely target for combination therapy with traditional drugs such as HU.

  11. Gender affects skin wound healing in plasminogen deficient mice.

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    Birgitte Rønø

    Full Text Available The fibrinolytic activity of plasmin plays a fundamental role in resolution of blood clots and clearance of extravascular deposited fibrin in damaged tissues. These vital functions of plasmin are exploited by malignant cells to accelerate tumor growth and facilitate metastases. Mice lacking functional plasmin thus display decreased tumor growth in a variety of cancer models. Interestingly, this role of plasmin has, in regard to skin cancer, been shown to be restricted to male mice. It remains to be clarified whether gender also affects other phenotypic characteristics of plasmin deficiency or if this gender effect is restricted to skin cancer. To investigate this, we tested the effect of gender on plasmin dependent immune cell migration, accumulation of hepatic fibrin depositions, skin composition, and skin wound healing. Gender did not affect immune cell migration or hepatic fibrin accumulation in neither wildtype nor plasmin deficient mice, and the existing differences in skin composition between males and females were unaffected by plasmin deficiency. In contrast, gender had a marked effect on the ability of plasmin deficient mice to heal skin wounds, which was seen as an accelerated wound closure in female versus male plasmin deficient mice. Further studies showed that this gender effect could not be reversed by ovariectomy, suggesting that female sex-hormones did not mediate the accelerated skin wound healing in plasmin deficient female mice. Histological examination of healed wounds revealed larger amounts of fibrotic scars in the provisional matrix of plasmin deficient male mice compared to female mice. These fibrotic scars correlated to an obstruction of cell infiltration of the granulation tissue, which is a prerequisite for wound healing. In conclusion, the presented data show that the gender dependent effect of plasmin deficiency is tissue specific and may be secondary to already established differences between genders, such as skin

  12. Histamine-dependent behavioral response to methamphetamine in 12-month-old male mice

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    Acevedo, Summer F.; Raber, Jacob

    2011-01-01

    Methamphetamine (MA) use is a growing problem across the United States. Effects of MA include hyperactivity and increased anxiety. Using a mouse model system, we examined behavioral performance in the open field and elevated zero maze and shock-startle response of 12-month-old wild-type mice injected with MA once (1mg/kg) 30 min prior to behavioral testing. MA treatment resulted in behavioral sensitization in the open field, consistent with studies in younger mice. There was an increased activity in the elevated zero maze and an increased shock-startle response 30 and 60 min post-injection. Since histamine mediates some effects of MA in the brain, we assessed whether 12-month-old mice lacking histidine decarboxylase (Hdc−/−), the enzyme required to synthesize histamine, respond differently to MA than wild-type (Hdc+/+) mice. Compared to saline treatment, acute and repeated MA administration increased activity in the open field and measures of anxiety, though more so in Hdc−/− than Hdc+/+ mice. In the elevated zero maze, opposite effects of MA on activity and measures of anxiety were seen in Hdc+/+ mice. In contrast, MA similarly increased the shock-startle response in Hdc−/− and Hdc+/+ mice, compared to saline-treated genotype-matched mice. These results are similar to those in younger mice suggesting that the effects are not age-dependent. Overall, single or repeated MA treatment causes histamine-dependent changes in 12-month-old mice in the open field and elevated zero-maze, but not in the shock-startle response. PMID:21466792

  13. D4 receptor deficiency in mice has limited effects on impulsivity and novelty seeking.

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    Helms, C M; Gubner, N R; Wilhelm, C J; Mitchell, S H; Grandy, D K

    2008-09-01

    Alleles of the human dopamine D(4) receptor (D(4)R) gene (DRD4.7) have repeatedly been found to correlate with novelty seeking, substance abuse, pathological gambling, and attention-deficit hyperactivity disorder (ADHD). If these various psychopathologies are a result of attenuated D(4)R-mediated signaling, mice lacking D(4)Rs (D(4)KO) should be more impulsive than wild-type (WT) mice and exhibit more novelty seeking. However, in our study, D(4)KO and WT mice showed similar levels of impulsivity as measured by delay discounting performance and response inhibition on a Go/No-go test, suggesting that D(4)R-mediated signaling may not affect impulsivity. D(4)KO mice were more active than WT mice in the first 5 min of a novel open field test, suggesting greater novelty seeking. For both genotypes, more impulsive mice habituated less in the novel open field. These data suggest that the absence of D(4)Rs is not sufficient to cause psychopathologies associated with heightened impulsivity and novelty seeking.

  14. Gastroesophageal reflux leads to esophageal cancer in a surgical model with mice

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    Chen Xiaoxin

    2009-07-01

    Full Text Available Abstract Background Esophago-gastroduodenal anastomosis with rats mimics the development of human Barrett's esophagus and esophageal adenocarcinoma by introducing mixed reflux of gastric and duodenal contents into the esophagus. However, use of this rat model for mechanistic and chemopreventive studies is limited due to lack of genetically modified rat strains. Therefore, a mouse model of esophageal adenocarcinoma is needed. Methods We performed reflux surgery on wild-type, p53A135V transgenic, and INK4a/Arf+/- mice of A/J strain. Some mice were also treated with omeprazole (1,400 ppm in diet, iron (50 mg/kg/m, i.p., or gastrectomy plus iron. Mouse esophagi were harvested at 20, 40 or 80 weeks after surgery for histopathological analysis. Results At week 20, we observed metaplasia in wild-type mice (5%, 1/20 and p53A135V mice (5.3%, 1/19. At week 40, metaplasia was found in wild-type mice (16.2%, 6/37, p53A135V mice (4.8%, 2/42, and wild-type mice also receiving gastrectomy and iron (6.7%, 1/15. Esophageal squamous cell carcinoma developed in INK4a/Arf+/- mice (7.1%, 1/14, and wild-type mice receiving gastrectomy and iron (21.4%, 3/14. Among 13 wild-type mice which were given iron from week 40 to 80, twelve (92.3% developed squamous cell carcinoma at week 80. None of these mice developed esophageal adenocarcinoma. Conclusion Surgically induced gastroesophageal reflux produced esophageal squamous cell carcinoma, but not esophageal adenocarcinoma, in mice. Dominant negative p53 mutation, heterozygous loss of INK4a/Arf, antacid treatment, iron supplementation, or gastrectomy failed to promote esophageal adenocarcinoma in these mice. Further studies are needed in order to develop a mouse model of esophageal adenocarcinoma.

  15. Photoreceptor cells with profound structural deficits can support useful vision in mice.

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    Thompson, Stewart; Blodi, Frederick R; Lee, Swan; Welder, Chris R; Mullins, Robert F; Tucker, Budd A; Stasheff, Steven F; Stone, Edwin M

    2014-03-25

    In animal models of degenerative photoreceptor disease, there has been some success in restoring photoreception by transplanting stem cell-derived photoreceptor cells into the subretinal space. However, only a small proportion of transplanted cells develop extended outer segments, considered critical for photoreceptor cell function. The purpose of this study was to determine whether photoreceptor cells that lack a fully formed outer segment could usefully contribute to vision. Retinal and visual function was tested in wild-type and Rds mice at 90 days of age (Rds(P90)). Photoreceptor cells of mice homozygous for the Rds mutation in peripherin 2 never develop a fully formed outer segment. The electroretinogram and multielectrode recording of retinal ganglion cells were used to test retinal responses to light. Three distinct visual behaviors were used to assess visual capabilities: the optokinetic tracking response, the discrimination-based visual water task, and a measure of the effect of vision on wheel running. Rds(P90) mice had reduced but measurable electroretinogram responses to light, and exhibited light-evoked responses in multiple types of retinal ganglion cells, the output neurons of the retina. In optokinetic and discrimination-based tests, acuity was measurable but reduced, most notably when contrast was decreased. The wheel running test showed that Rds(P90) mice needed 3 log units brighter luminance than wild type to support useful vision (10 cd/m(2)). Photoreceptors that lack fully formed outer segments can support useful vision. This challenges the idea that normal cellular structure needs to be completely reproduced for transplanted cells to contribute to useful vision.

  16. Conjugated linoleic acid ameliorates inflammation-induced colorectal cancer in mice through activation of PPARgamma.

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    Evans, Nicholas P; Misyak, Sarah A; Schmelz, Eva M; Guri, Amir J; Hontecillas, Raquel; Bassaganya-Riera, Josep

    2010-03-01

    Conjugated linoleic acid (CLA) exerts a protective effect on experimental inflammatory bowel disease and shows promise as a chemopreventive agent against colorectal cancer (CRC) in mice, although the mechanisms by which it exerts its beneficial effects against malignancies in the gut are not completely understood. Mice lacking PPARgamma in immune and epithelial cells and PPARgamma-expressing littermates were fed either control or CLA-supplemented (1 g CLA/100 g) diets to determine the role of PPARgamma in inflammation-induced CRC. To induce tumor formation and colitis, mice were treated with azoxymethane and then challenged with 2% dextran sodium sulfate, respectively. Dietary CLA ameliorated disease activity, decreased colitis, and prevented adenocarcinoma formation in the PPARgamma-expressing floxed mice but not in the tissue-specific PPARgamma-null mice. Dietary CLA supplementation significantly decreased the percentages of macrophages in the mesenteric lymph nodes (MLN) regardless of the genotype and increased regulatory T cell numbers in MLN of PPARgamma-expressing, but not in the tissue-specific, PPARgamma-null mice. Colonic tumor necrosis factor-alpha mRNA expression was significantly suppressed in CLA-fed, PPARgamma-expressing mice. This study suggests CLA ameliorates colitis and prevents tumor formation in part through a PPARgamma-dependent mechanism.

  17. Maximal Oxygen Consumption is Reduced in Aquaporin-1 Knockout Mice

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    Samer Al-Samir

    2016-08-01

    Full Text Available We have measured maximal oxygen consumption (V’O2,max of mice lacking one or two of the established mouse red-cell CO2 channels AQP1, AQP9 and Rhag. We intended to study whether these proteins, by acting as channels for O2, determine O2 exchange in the lung and in the periphery. We found that V’O2,max as determined by the Helox technique is reduced by ~ 16%, when AQP1 is knocked out, but not when AQP9 or Rhag are lacking. This figure holds for animals respiring normoxic as well as hypoxic gas mixtures. To see whether the reduction of V’O2,max is due to impaired O2 uptake in the lung, we measured carotid arterial O2 saturation (SO2 by pulse oximetry. Neither under normoxic (inspiratory O2 21% nor under hypoxic conditions (11% O2 is there a difference in SO2 between AQP1null and WT mice, suggesting that AQP1 is not critical for O2 uptake in the lung. The fact that the % reduction of V’O2,max is identical in normoxia and hypoxia indicates moreover that the limitation of V’O2,max is not due to an O2 diffusion problem, neither in the lung nor in the periphery. Instead, it appears likely that AQP1null animals exhibit a reduced V’O2,max due to the reduced wall thickness and muscle mass of the left ventricles of their hearts, as reported previously. We conclude that very likely the properties of the hearts of AQP1 knockout mice cause a reduced maximal cardiac output and thus cause a reduced V’O2,max, which constitutes a new phenotype of these mice.

  18. B lymphocytes not required for progression from insulitis to diabetes in non-obese diabetic mice.

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    Charlton, B; Zhang, M D; Slattery, R M

    2001-12-01

    Previous studies have implicated B lymphocytes in the pathogenesis of diabetes in the non-obese diabetic (NOD) mouse. While it is clear that B lymphocytes are necessary, it has not been clear at which stage of disease they play a role; early, late or both. To clarify when B lymphocytes are needed, T lymphocytes were transferred from 5-week-old NOD female mice to age-matched NOD/severe combined immunodeficiency (SCID) recipient mice. NOD/SCID mice, which lack functionally mature T and B lymphocytes, do not normally develop insulitis or insulin-dependent diabetes melitus (IDDM). The NOD/SCID mice that received purified T lymphocytes from 5-week-old NOD mice subsequently developed insulitis and diabetes even though they did not have detectable B lymphocytes. This suggests that while B lymphocytes may be essential for an initial priming event they are not requisite for disease progression in the NOD mouse.

  19. Perturbed desmosomal cadherin expression in grainy head-like 1-null mice.

    Science.gov (United States)

    Wilanowski, Tomasz; Caddy, Jacinta; Ting, Stephen B; Hislop, Nikki R; Cerruti, Loretta; Auden, Alana; Zhao, Lin-Lin; Asquith, Stephen; Ellis, Sarah; Sinclair, Rodney; Cunningham, John M; Jane, Stephen M

    2008-03-19

    In Drosophila, the grainy head (grh) gene plays a range of key developmental roles through the regulation of members of the cadherin gene family. We now report that mice lacking the grh homologue grainy head-like 1 (Grhl1) exhibit hair and skin phenotypes consistent with a reduction in expression of the genes encoding the desmosomal cadherin, desmoglein 1 (Dsg1). Grhl1-null mice show an initial delay in coat growth, and older mice exhibit hair loss as a result of poor anchoring of the hair shaft in the follicle. The mice also develop palmoplantar keratoderma, analogous to humans with DSG1 mutations. Sequence analysis, DNA binding, and chromatin immunoprecipitation experiments demonstrate that the human and mouse Dsg1 promoters are direct targets of GRHL1. Ultrastructural analysis reveals reduced numbers of abnormal desmosomes in the interfollicular epidermis. These findings establish GRHL1 as an important regulator of the Dsg1 genes in the context of hair anchorage and epidermal differentiation, and suggest that cadherin family genes are key targets of the grainy head-like genes across 700 million years of evolution.

  20. Semi-automatic classification of skeletal morphology in genetically altered mice using flat-panel volume computed tomography.

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    Christian Dullin

    2007-07-01

    Full Text Available Rapid progress in exploring the human and mouse genome has resulted in the generation of a multitude of mouse models to study gene functions in their biological context. However, effective screening methods that allow rapid noninvasive phenotyping of transgenic and knockout mice are still lacking. To identify murine models with bone alterations in vivo, we used flat-panel volume computed tomography (fpVCT for high-resolution 3-D imaging and developed an algorithm with a computational intelligence system. First, we tested the accuracy and reliability of this approach by imaging discoidin domain receptor 2- (DDR2- deficient mice, which display distinct skull abnormalities as shown by comparative landmark-based analysis. High-contrast fpVCT data of the skull with 200 microm isotropic resolution and 8-s scan time allowed segmentation and computation of significant shape features as well as visualization of morphological differences. The application of a trained artificial neuronal network to these datasets permitted a semi-automatic and highly accurate phenotype classification of DDR2-deficient compared to C57BL/6 wild-type mice. Even heterozygous DDR2 mice with only subtle phenotypic alterations were correctly determined by fpVCT imaging and identified as a new class. In addition, we successfully applied the algorithm to classify knockout mice lacking the DDR1 gene with no apparent skull deformities. Thus, this new method seems to be a potential tool to identify novel mouse phenotypes with skull changes from transgenic and knockout mice on the basis of random mutagenesis as well as from genetic models. However for this purpose, new neuronal networks have to be created and trained. In summary, the combination of fpVCT images with artificial neuronal networks provides a reliable, novel method for rapid, cost-effective, and noninvasive primary screening tool to detect skeletal phenotypes in mice.

  1. Adaptation of enterovirus 71 to adult interferon deficient mice.

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    Elizabeth A Caine

    Full Text Available Non-polio enteroviruses, including enterovirus 71 (EV71, have caused severe and fatal cases of hand, foot and mouth disease (HFMD in the Asia-Pacific region. The development of a vaccine or antiviral against these pathogens has been hampered by the lack of a reliable small animal model. In this study, a mouse adapted EV71 strain was produced by conducting serial passages through A129 (α/β interferon (IFN receptor deficient and AG129 (α/β, γ IFN receptor deficient mice. A B2 sub genotype of EV71 was inoculated intraperitoneally (i.p. into neonatal AG129 mice and brain-harvested virus was subsequently passaged through 12 and 15 day-old A129 mice. When tested in 10 week-old AG129 mice, this adapted strain produced 100% lethality with clinical signs including limb paralysis, eye irritation, loss of balance, and death. This virus caused only 17% mortality in same age A129 mice, confirming that in the absence of a functional IFN response, adult AG129 mice are susceptible to infection by adapted EV71 isolates. Subsequent studies in adult AG129 and young A129 mice with the adapted EV71 virus examined the efficacy of an inactivated EV71 candidate vaccine and determined the role of humoral immunity in protection. Passive transfer of rabbit immune sera raised against the EV71 vaccine provided protection in a dose dependent manner in 15 day-old A129 mice. Intramuscular injections (i.m. in five week-old AG129 mice with the alum adjuvanted vaccine also provided protection against the mouse adapted homologous strain. No clinical signs of disease or mortality were observed in vaccinated animals, which received a prime-and-boost, whereas 71% of control animals were euthanized after exhibiting systemic clinical signs (P<0.05. The development of this animal model will facilitate studies on EV71 pathogenesis, antiviral testing, the evaluation of immunogenicity and efficacy of vaccine candidates, and has the potential to establish correlates of protection

  2. Activation of PPARα decreases bile acids in livers of female mice while maintaining bile flow and biliary bile acid excretion.

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    Zhang, Youcai; Lickteig, Andrew J; Csanaky, Iván L; Klaassen, Curtis D

    2018-01-01

    Fibrates are hypolipidemic drugs that act as activators of peroxisome proliferator-activated receptor α (PPARα). In both humans and rodents, females were reported to be less responsive to fibrates than males. Previous studies on fibrates and PPARα usually involved male mice, but little has been done in females. The present study aimed to provide the first comprehensive analysis of the effects of clofibrate (CLOF) and PPARα on bile acid (BA) homeostasis in female mice. Study in WT male mice showed that a 4-day CLOF treatment increased liver weight, bile flow, and biliary BA excretion, but decreased total BAs in both serum and liver. In contrast, WT female mice were less susceptible to these CLOF-mediated responses observed in males. In WT female mice, CLOF decreased total BAs in the liver, but had little effect on the mRNAs of hepatic BA-related genes. Next, a comparative analysis between WT and PPARα-null female mice showed that lack of PPARα in female mice decreased total BAs in serum, but had little effect on total BAs in liver or bile. However, lack of PPARα in female mice increased mRNAs of BA synthetic enzymes (Cyp7a1, Cyp8b1, Cyp27a1, and Cyp7b1) and transporters (Ntcp, Oatp1a1, Oatp1b2, and Mrp3). Furthermore, the increase of Cyp7a1 in PPARα-null female mice was associated with an increase in liver Fxr-Shp-Lrh-1 signaling. In conclusion, female mice are resistant to CLOF-mediated effects on BA metabolism observed in males, which could be attributed to PPARα-mediated suppression in females on genes involved in BA synthesis and transport. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Gold thread implantation promotes hair growth in human and mice

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    Kim, Jong-Hwan; Cho, Eun-Young; Kwon, Euna; Kim, Woo-Ho; Park, Jin-Sung; Lee, Yong-Soon

    2017-01-01

    Thread-embedding therapy has been widely applied for cosmetic purposes such as wrinkle reduction and skin tightening. Particularly, gold thread was reported to support connective tissue regeneration, but, its role in hair biology remains largely unknown due to lack of investigation. When we implanted gold thread and Happy Lift™ in human patient for facial lifting, we unexpectedly found an increase of hair regrowth in spite of no use of hair growth medications. When embedded into the depilated dorsal skin of mice, gold thread or polyglycolic acid (PGA) thread, similarly to 5% minoxidil, significantly increased the number of hair follicles on day 14 after implantation. And, hair re-growth promotion in the gold threadimplanted mice were significantly higher than that in PGA thread group on day 11 after depilation. In particular, the skin tissue of gold thread-implanted mice showed stronger PCNA staining and higher collagen density compared with control mice. These results indicate that gold thread implantation can be an effective way to promote hair re-growth although further confirmatory study is needed for more information on therapeutic mechanisms and long-term safety. PMID:29399026

  4. Antibody response is required for protection from Theiler's virus-induced encephalitis in C57BL/6 mice in the absence of CD8+ T cells

    International Nuclear Information System (INIS)

    Kang, B.-S.; Palma, Joann P.; Lyman, Michael A.; Dal Canto, Mauro; Kim, Byung S.

    2005-01-01

    Intracerebral infection of susceptible mice with Theiler's murine encephalomyelitis virus (TMEV) induces immune-mediated demyelinating disease and this system serves as a relevant infectious model for human multiple sclerosis. It was previously shown that β 2 M-deficient C57BL/6 mice lacking functional CD8 + T cells display increased viral persistence and enhanced susceptibility to TMEV-induced demyelination, and yet the majority of mice are free of clinical signs. To understand the mechanisms involved in this general resistance of C57BL/6 mice in the absence of CTL responses, mice (μMT) deficient in the B-cell compartment lacking membrane IgM molecules were treated with anti-CD8 antibody and then infected with TMEV. Although little difference in the proliferative responses of peripheral T cells to UV-inactivated TMEV and the resistance to demyelinating disease was observed between virus-infected μMT and control B6 mice, the levels of CD4 + T cells were higher in the CNS of μMT mice. However, after treatment with anti-CD8 antibody, 100% of the mice displayed clinical gray matter disease and prolonged viral persistence in μMT mice, while only 10% of B6 mice showed clinical symptoms and very low viral persistence. Transfusion of sera from TMEV-infected B6 mice into anti-CD8 antibody-treated μMT mice partially restored resistance to virus-induced encephalitis. These results indicate that the early anti-viral antibody response is also important in the protection from TMEV-induced encephalitis particularly in the absence of CD8 + T cells

  5. Sick sinus syndrome in HCN1-deficient mice.

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    Fenske, Stefanie; Krause, Stefanie C; Hassan, Sami I H; Becirovic, Elvir; Auer, Franziska; Bernard, Rebekka; Kupatt, Christian; Lange, Philipp; Ziegler, Tilman; Wotjak, Carsten T; Zhang, Henggui; Hammelmann, Verena; Paparizos, Christos; Biel, Martin; Wahl-Schott, Christian A

    2013-12-17

    Sinus node dysfunction (SND) is a major clinically relevant disease that is associated with sudden cardiac death and requires surgical implantation of electric pacemaker devices. Frequently, SND occurs in heart failure and hypertension, conditions that lead to electric instability of the heart. Although the pathologies of acquired SND have been studied extensively, little is known about the molecular and cellular mechanisms that cause congenital SND. Here, we show that the HCN1 protein is highly expressed in the sinoatrial node and is colocalized with HCN4, the main sinoatrial pacemaker channel isoform. To characterize the cardiac phenotype of HCN1-deficient mice, a detailed functional characterization of pacemaker mechanisms in single isolated sinoatrial node cells, explanted beating sinoatrial node preparation, telemetric in vivo electrocardiography, echocardiography, and in vivo electrophysiology was performed. On the basis of these experiments we demonstrate that mice lacking the pacemaker channel HCN1 display congenital SND characterized by bradycardia, sinus dysrhythmia, prolonged sinoatrial node recovery time, increased sinoatrial conduction time, and recurrent sinus pauses. As a consequence of SND, HCN1-deficient mice display a severely reduced cardiac output. We propose that HCN1 stabilizes the leading pacemaker region within the sinoatrial node and hence is crucial for stable heart rate and regular beat-to-beat variation. Furthermore, we suggest that HCN1-deficient mice may be a valuable genetic disease model for human SND.

  6. Course of induced infection by Eimeria krijgsmannni in immunocompetent and immunodeficient mice.

    Science.gov (United States)

    Ono, Yuina; Matsubayashi, Makoto; Kawaguchi, Hiroaki; Tsujio, Masashi; Mizuno, Masanobu; Tanaka, Tetsuya; Masatani, Tatsunori; Matsui, Toshihiro; Matsuo, Tomohide

    2016-01-01

    Recently, we have demonstrated the utility of Eimeria krijgsmanni as a novel mouse eimerian parasite for elucidating the biological diversity. The parasite showed notable infectivity to mice with various levels of immune status and susceptibility to antimicrobial agents including coccidiostat. However, the detailed lifecycle of E. krijgsmanni had not yet been determined and this information was lacking in discussion of previous findings. In the present study, we clarified the morphological characteristics of E. krijgsmanni and its lifecycle in normal mice, and examined the effects in immunodeficient mice and lifecycle stage for challenge infections after the primary inoculation. In immunocompetent mice, the lifecycle consisted of four asexual stages and the sexual sages followed by formation of oocysts during the prepatent periods. Interestingly, the second-generation meronts were detected in all observation periods after the disappearance of the other stages. For the challenge infection of immunodeficient mice, all developmental stages except for the second generation meronts were temporarily vanished. This finding suggests a "rest" or marked delay in development and a "restart" of the promotion toward the next generations. The second generation meronts may play an important role in the lifecycle of E. krijgsmanni.

  7. Functions of TAM RTKs in regulating spermatogenesis and male fertility in mice.

    Science.gov (United States)

    Chen, Yongmei; Wang, Huizhen; Qi, Nan; Wu, Hui; Xiong, Weipeng; Ma, Jing; Lu, Qingxian; Han, Daishu

    2009-10-01

    Mice lacking TYRO3, AXL and MER (TAM) receptor tyrosine kinases (RTKs) are male sterile. The mechanism of TAM RTKs in regulating male fertility remains unknown. In this study, we analyzed in more detail the testicular phenotype of TAM triple mutant (TAM(-/-)) mice with an effort to understand the mechanism. We demonstrate that the three TAM RTKs cooperatively regulate male fertility, and MER appears to be more important than AXL and TYRO3. TAM(-/-) testes showed a progressive loss of germ cells from elongated spermatids to spermatogonia. Young adult TAM(-/-) mice exhibited oligo-astheno-teratozoospermia and various morphological malformations of sperm cells. As the mice aged, the germ cells were eventually depleted from the seminiferous tubules. Furthermore, we found that TAM(-/-) Sertoli cells have an impaired phagocytic activity and a large number of differentially expressed genes compared to wild-type controls. By contrast, the function of Leydig cells was not apparently affected by the mutation of TAM RTKs. Therefore, we conclude that the suboptimal function of Sertoli cells leads to the impaired spermatogenesis in TAM(-/-) mice. The results provide novel insight into the mechanism of TAM RTKs in regulating male fertility.

  8. Smoothelin-B deficiency results in reduced arterial contractility, hypertension, and cardiac hypertrophy in mice

    NARCIS (Netherlands)

    Rensen, Sander S.; Niessen, Petra M.; van Deursen, Jan M.; Janssen, Ben J.; Heijman, Edwin; Hermeling, Evelien; Meens, Merlijn; Lie, Natascha; Gijbels, Marion J.; Strijkers, Gustav J.; Doevendans, Pieter A.; Hofker, Marten H.; de Mey, Jo G. R.; van Eys, Guillaume J.

    2008-01-01

    Smoothelins are actin-binding proteins that are abundantly expressed in healthy visceral (smoothelin-A) and vascular (smoothelin-B) smooth muscle. Their expression is strongly associated with the contractile phenotype of smooth muscle cells. Analysis of mice lacking both smoothelins (Smtn-A/B(-/-)

  9. Cholesterol reduction and lack of genotoxic or toxic effects in mice after repeated 21-day oral intake of lemongrass (Cymbopogon citratus) essential oil.

    Science.gov (United States)

    Costa, Celso A R A; Bidinotto, Lucas T; Takahira, Regina K; Salvadori, Daisy M F; Barbisan, Luís F; Costa, Mirtes

    2011-09-01

    Cymbopogon citratus (lemongrass) is currently used in traditional folk medicine. Although this species presents widespread use, there are no scientific data on its efficacy or safety after repeated treatments. Therefore, this work investigated the toxicity and genotoxicity of this lemongrass's essential oil (EO) in male Swiss mice. The single LD(50) based on a 24h acute oral toxicity study was found to be around 3500 mg/kg. In a repeated-dose 21-day oral toxicity study, mice were randomly assigned to two control groups, saline- or Tween 80 0.01%-treated groups, or one of the three experimental groups receiving lemongrass EO (1, 10 or 100mg/kg). No significant changes in gross pathology, body weight, absolute or relative organ weights, histology (brain, heart, kidneys, liver, lungs, stomach, spleen and urinary bladder), urinalysis or clinical biochemistry were observed in EO-treated mice relative to the control groups. Additionally, blood cholesterol was reduced after EO-treatment at the highest dose tested. Similarly, data from the comet assay in peripheral blood cells showed no genotoxic effect from the EO. In conclusion, our findings verified the safety of lemongrass intake at the doses used in folk medicine and indicated the beneficial effect of reducing the blood cholesterol level. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Cardiomyocyte specific deletion of Crif1 causes mitochondrial cardiomyopathy in mice.

    Directory of Open Access Journals (Sweden)

    Juhee Shin

    Full Text Available Mitochondria are key organelles dedicated to energy production. Crif1, which interacts with the large subunit of the mitochondrial ribosome, is indispensable for the mitochondrial translation and membrane insertion of respiratory subunits. To explore the physiological function of Crif1 in the heart, Crif1(f/f mice were crossed with Myh6-cre/Esr1 transgenic mice, which harbor cardiomyocyte-specific Cre activity in a tamoxifen-dependent manner. The tamoxifen injections were given at six weeks postnatal, and the mutant mice survived only five months due to hypertrophic heart failure. In the mutant cardiac muscles, mitochondrial mass dramatically increased, while the inner structure was altered with lack of cristae. Mutant cardiac muscles showed decreased rates of oxygen consumption and ATP production, suggesting that Crif1 plays a critical role in the maintenance of both mitochondrial structure and respiration in cardiac muscles.

  11. Mice with ablated adult brain neurogenesis are not impaired in antidepressant response to chronic fluoxetine.

    Science.gov (United States)

    Jedynak, Paulina; Kos, Tomasz; Sandi, Carmen; Kaczmarek, Leszek; Filipkowski, Robert K

    2014-09-01

    The neurogenesis hypothesis of major depression has two main facets. One states that the illness results from decreased neurogenesis while the other claims that the very functioning of antidepressants depends on increased neurogenesis. In order to verify the latter, we have used cyclin D2 knockout mice (cD2 KO mice), known to have virtually no adult brain neurogenesis, and we demonstrate that these mice successfully respond to chronic fluoxetine. After unpredictable chronic mild stress, mutant mice showed depression-like behavior in forced swim test, which was eliminated with chronic fluoxetine treatment, despite its lack of impact on adult hippocampal neurogenesis in cD2 KO mice. Our results suggest that new neurons are not indispensable for the action of antidepressants such as fluoxetine. Using forced swim test and tail suspension test, we also did not observe depression-like behavior in control cD2 KO mice, which argues against the link between decreased adult brain neurogenesis and major depression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Neuropeptide Y deficiency attenuates responses to fasting and high-fat diet in obesity-prone mice.

    Science.gov (United States)

    Patel, Hiralben R; Qi, Yong; Hawkins, Evan J; Hileman, Stanley M; Elmquist, Joel K; Imai, Yumi; Ahima, Rexford S

    2006-11-01

    Neuropeptide Y (NPY) stimulates feeding and weight gain, but deletion of the NPY gene does not affect food intake and body weight in mice bred on a mixed genetic background. We reasoned that the orexigenic action of NPY would be evident in C57Bl/6J mice susceptible to obesity. NPY deficiency has no significant effect in mice fed a normal rodent diet. However, energy expenditure is elevated during fasting, and hyperphagia and weight gain are blunted during refeeding. Expression of agouti-related peptide (AGRP) in the hypothalamus is increased in NPY knockout (NPYko) than wild-type mice, but unlike wild type there is no further increase in AGRP when NPYko mice are fasted. Moreover, NPYko mice have higher oxygen consumption and uncoupling protein-1 expression in brown adipose tissue during fasting. The failure of an increase in orexigenic peptides and higher thermogenesis may contribute to attenuation of weight gain when NPYko mice are refed. C57Bl/6J mice lacking NPY are also less susceptible to diet-induced obesity (DIO) as a result of reduced feeding and increased energy expenditure. The resistance to DIO in NPYko mice is associated with a reduction in nocturnal feeding and increased expression of anorexigenic hypothalamic peptides. Insulin, leptin, and triglyceride levels increase with adiposity in both wild-type and NPYko mice.

  13. Sex differences in the acute locomotor response to methamphetamine in BALB/c mice.

    Science.gov (United States)

    Ohia-Nwoko, Odochi; Haile, Colin N; Kosten, Therese A

    2017-06-01

    Women use methamphetamine more frequently than men and are more vulnerable to its negative psychological effects. Rodent models have been an essential tool for evaluating the sex-dependent effects of psychostimulants; however, evidence of sex differences in the behavioral responses to methamphetamine in mice is lacking. In the present study, we investigated acute methamphetamine-induced (1mg/kg and 4mg/kg) locomotor activation in female and male BALB/c mice. We also evaluated whether basal locomotor activity was associated with the methamphetamine-induced locomotor response. The results indicated that female BALB/c mice displayed enhanced methamphetamine-induced locomotor activity compared to males, while basal locomotor activity was positively correlated with methamphetamine-induced activity in males, but not females. This study is the first to show sex-dependent locomotor effects of methamphetamine in BALB/c mice. Our observations emphasize the importance of considering sex when assessing behavioral responses to methamphetamine. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Altered Hematopoiesis in Mice Lacking DNA Polymerase μ Is Due to Inefficient Double-Strand Break Repair

    Science.gov (United States)

    Lucas, Daniel; Escudero, Beatriz; Ligos, José Manuel; Segovia, Jose Carlos; Estrada, Juan Camilo; Terrados, Gloria; Blanco, Luis; Samper, Enrique; Bernad, Antonio

    2009-01-01

    Polymerase mu (Polμ) is an error-prone, DNA-directed DNA polymerase that participates in non-homologous end-joining (NHEJ) repair. In vivo, Polμ deficiency results in impaired Vκ-Jκ recombination and altered somatic hypermutation and centroblast development. In Polμ−/− mice, hematopoietic development was defective in several peripheral and bone marrow (BM) cell populations, with about a 40% decrease in BM cell number that affected several hematopoietic lineages. Hematopoietic progenitors were reduced both in number and in expansion potential. The observed phenotype correlates with a reduced efficiency in DNA double-strand break (DSB) repair in hematopoietic tissue. Whole-body γ-irradiation revealed that Polμ also plays a role in DSB repair in non-hematopoietic tissues. Our results show that Polμ function is required for physiological hematopoietic development with an important role in maintaining early progenitor cell homeostasis and genetic stability in hematopoietic and non-hematopoietic tissues. PMID:19229323

  15. Effects of dopamine D1-like and D2-like antagonists on cocaine discrimination in muscarinic receptor knockout mice.

    Science.gov (United States)

    Thomsen, Morgane; Caine, Simon Barak

    2016-04-05

    Muscarinic and dopamine brain systems interact intimately, and muscarinic receptor ligands, like dopamine ligands, can modulate the reinforcing and discriminative stimulus (S(D)) effects of cocaine. To enlighten the dopamine/muscarinic interactions as they pertain to the S(D) effects of cocaine, we evaluated whether muscarinic M1, M2 or M4 receptors are necessary for dopamine D1 and/or D2 antagonist mediated modulation of the S(D) effects of cocaine. Knockout mice lacking M1, M2, or M4 receptors, as well as control wild-type mice and outbred Swiss-Webster mice, were trained to discriminate 10mg/kg cocaine from saline in a food-reinforced drug discrimination procedure. Effects of pretreatments with the dopamine D1 antagonist SCH 23390 and the dopamine D2 antagonist eticlopride were evaluated. In intact mice, both SCH 23390 and eticlopride attenuated the cocaine discriminative stimulus effect, as expected. SCH 23390 similarly attenuated the cocaine discriminative stimulus effect in M1 knockout mice, but not in mice lacking M2 or M4 receptors. The effects of eticlopride were comparable in each knockout strain. These findings demonstrate differences in the way that D1 and D2 antagonists modulate the S(D) effects of cocaine, D1 modulation being at least partially dependent upon activity at the inhibitory M2/M4 muscarinic subtypes, while D2 modulation appeared independent of these systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Peripheral nervous system insulin resistance in ob/ob mice

    Science.gov (United States)

    2013-01-01

    Background A reduction in peripheral nervous system (PNS) insulin signaling is a proposed mechanism that may contribute to sensory neuron dysfunction and diabetic neuropathy. Neuronal insulin resistance is associated with several neurological disorders and recent evidence has indicated that dorsal root ganglion (DRG) neurons in primary culture display altered insulin signaling, yet in vivo results are lacking. Here, experiments were performed to test the hypothesis that the PNS of insulin-resistant mice displays altered insulin signal transduction in vivo. For these studies, nondiabetic control and type 2 diabetic ob/ob mice were challenged with an intrathecal injection of insulin or insulin-like growth factor 1 (IGF-1) and downstream signaling was evaluated in the DRG and sciatic nerve using Western blot analysis. Results The results indicate that insulin signaling abnormalities documented in other “insulin sensitive” tissues (i.e. muscle, fat, liver) of ob/ob mice are also present in the PNS. A robust increase in Akt activation was observed with insulin and IGF-1 stimulation in nondiabetic mice in both the sciatic nerve and DRG; however this response was blunted in both tissues from ob/ob mice. The results also suggest that upregulated JNK activation and reduced insulin receptor expression could be contributory mechanisms of PNS insulin resistance within sensory neurons. Conclusions These findings contribute to the growing body of evidence that alterations in insulin signaling occur in the PNS and may be a key factor in the pathogenesis of diabetic neuropathy. PMID:24252636

  17. Blocking beta 2-adrenergic receptor inhibits dendrite ramification in a mouse model of Alzheimer's disease.

    Science.gov (United States)

    Wu, Qin; Sun, Jin-Xia; Song, Xiang-He; Wang, Jing; Xiong, Cun-Quan; Teng, Fei-Xiang; Gao, Cui-Xiang

    2017-09-01

    Dendrite ramification affects synaptic strength and plays a crucial role in memory. Previous studies revealed a correlation between beta 2-adrenergic receptor dysfunction and Alzheimer's disease (AD), although the mechanism involved is still poorly understood. The current study investigated the potential effect of the selective β 2 -adrenergic receptor antagonist, ICI 118551 (ICI), on Aβ deposits and AD-related cognitive impairment. Morris water maze test results demonstrated that the performance of AD-transgenic (TG) mice treated with ICI (AD-TG/ICI) was significantly poorer compared with NaCl-treated AD-TG mice (AD-TG/NaCl), suggesting that β 2 -adrenergic receptor blockage by ICI might reduce the learning and memory abilities of mice. Golgi staining and immunohistochemical staining revealed that blockage of the β 2 -adrenergic receptor by ICI treatment decreased the number of dendritic branches, and ICI treatment in AD-TG mice decreased the expression of hippocampal synaptophysin and synapsin 1. Western blot assay results showed that the blockage of β 2 -adrenergic receptor increased amyloid-β accumulation by downregulating hippocampal α-secretase activity and increasing the phosphorylation of amyloid precursor protein. These findings suggest that blocking the β 2 -adrenergic receptor inhibits dendrite ramification of hippocampal neurons in a mouse model of AD.

  18. Ethanol metabolism, oxidative stress, and endoplasmic reticulum stress responses in the lungs of hepatic alcohol dehydrogenase deficient deer mice after chronic ethanol feeding

    Energy Technology Data Exchange (ETDEWEB)

    Kaphalia, Lata [Department of Internal Medicine, The University of Texas Medical Branch, Galveston, TX 775555 (United States); Boroumand, Nahal [Department of Pathology, The University of Texas Medical Branch, Galveston, TX 775555 (United States); Hyunsu, Ju [Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, Galveston, TX 775555 (United States); Kaphalia, Bhupendra S., E-mail: bkaphali@utmb.edu [Department of Pathology, The University of Texas Medical Branch, Galveston, TX 775555 (United States); Calhoun, William J. [Department of Internal Medicine, The University of Texas Medical Branch, Galveston, TX 775555 (United States)

    2014-06-01

    Consumption and over-consumption of alcoholic beverages are well-recognized contributors to a variety of pulmonary disorders, even in the absence of intoxication. The mechanisms by which alcohol (ethanol) may produce disease include oxidative stress and prolonged endoplasmic reticulum (ER) stress. Many aspects of these processes remain incompletely understood due to a lack of a suitable animal model. Chronic alcohol over-consumption reduces hepatic alcohol dehydrogenase (ADH), the principal canonical metabolic pathway of ethanol oxidation. We therefore modeled this situation using hepatic ADH-deficient deer mice fed 3.5% ethanol daily for 3 months. Blood ethanol concentration was 180 mg% in ethanol fed mice, compared to < 1.0% in the controls. Acetaldehyde (oxidative metabolite of ethanol) was minimally, but significantly increased in ethanol-fed vs. pair-fed control mice. Total fatty acid ethyl esters (FAEEs, nonoxidative metabolites of ethanol) were 47.6 μg/g in the lungs of ethanol-fed mice as compared to 1.5 μg/g in pair-fed controls. Histological and immunohistological evaluation showed perivascular and peribronchiolar lymphocytic infiltration, and significant oxidative injury, in the lungs of ethanol-fed mice compared to pair-fed controls. Several fold increases for cytochrome P450 2E1, caspase 8 and caspase 3 found in the lungs of ethanol-fed mice as compared to pair-fed controls suggest role of oxidative stress in ethanol-induced lung injury. ER stress and unfolded protein response signaling were also significantly increased in the lungs of ethanol-fed mice. Surprisingly, no significant activation of inositol-requiring enzyme-1α and spliced XBP1 was observed indicating a lack of activation of corrective mechanisms to reinstate ER homeostasis. The data suggest that oxidative stress and prolonged ER stress, coupled with formation and accumulation of cytotoxic FAEEs may contribute to the pathogenesis of alcoholic lung disease. - Highlights: • Chronic

  19. Ethanol metabolism, oxidative stress, and endoplasmic reticulum stress responses in the lungs of hepatic alcohol dehydrogenase deficient deer mice after chronic ethanol feeding

    International Nuclear Information System (INIS)

    Kaphalia, Lata; Boroumand, Nahal; Hyunsu, Ju; Kaphalia, Bhupendra S.; Calhoun, William J.

    2014-01-01

    Consumption and over-consumption of alcoholic beverages are well-recognized contributors to a variety of pulmonary disorders, even in the absence of intoxication. The mechanisms by which alcohol (ethanol) may produce disease include oxidative stress and prolonged endoplasmic reticulum (ER) stress. Many aspects of these processes remain incompletely understood due to a lack of a suitable animal model. Chronic alcohol over-consumption reduces hepatic alcohol dehydrogenase (ADH), the principal canonical metabolic pathway of ethanol oxidation. We therefore modeled this situation using hepatic ADH-deficient deer mice fed 3.5% ethanol daily for 3 months. Blood ethanol concentration was 180 mg% in ethanol fed mice, compared to < 1.0% in the controls. Acetaldehyde (oxidative metabolite of ethanol) was minimally, but significantly increased in ethanol-fed vs. pair-fed control mice. Total fatty acid ethyl esters (FAEEs, nonoxidative metabolites of ethanol) were 47.6 μg/g in the lungs of ethanol-fed mice as compared to 1.5 μg/g in pair-fed controls. Histological and immunohistological evaluation showed perivascular and peribronchiolar lymphocytic infiltration, and significant oxidative injury, in the lungs of ethanol-fed mice compared to pair-fed controls. Several fold increases for cytochrome P450 2E1, caspase 8 and caspase 3 found in the lungs of ethanol-fed mice as compared to pair-fed controls suggest role of oxidative stress in ethanol-induced lung injury. ER stress and unfolded protein response signaling were also significantly increased in the lungs of ethanol-fed mice. Surprisingly, no significant activation of inositol-requiring enzyme-1α and spliced XBP1 was observed indicating a lack of activation of corrective mechanisms to reinstate ER homeostasis. The data suggest that oxidative stress and prolonged ER stress, coupled with formation and accumulation of cytotoxic FAEEs may contribute to the pathogenesis of alcoholic lung disease. - Highlights: • Chronic

  20. Benzene activates caspase-4 and -12 at the transcription level, without an association with apoptosis, in mouse bone marrow cells lacking the p53 gene

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Jung-Yeon; Han, Jeong-Hee; Yoon, Byung-Il [Kangwon National University, School of Veterinary Medicine, Chuncheon, Gangwon (Korea); Hirabayashi, Yoko; Kodama, Yukio; Kanno, Jun [National Institute of Health Sciences, Division of Cellular and Molecular Toxicology, Center for Biological Safety and Research, Tokyo (Japan); Choi, Yang-Kyu [Konkuk University, College of Veterinary Medicine, Seoul (Korea); Inoue, Tohru [National Institute of Health Sciences, Biological Safety and Research Center, Tokyo (Japan)

    2009-08-15

    Benzene is a well-known environmental pollutant that can induce hematotoxicity, aplastic anemia, acute myelogenous leukemia, and lymphoma. However, although benzene metabolites are known to induce oxidative stress and disrupt the cell cycle, the mechanism underlying lympho/leukemogenicity is not fully understood. Caspase-4 (alias caspase-11) and -12 are inflammatory caspases implicated in inflammation and endoplasmic reticulum stress-induced apoptosis. The objectives of this study were to investigate the altered expression of caspase-4 and -12 in mouse bone marrow after benzene exposure and to determine whether their alterations are associated with benzene-induced bone marrow toxicity, especially cellular apoptosis. In addition, we evaluated whether the p53 gene is involved in regulating the mechanism, using both wild-type (WT) mice and mice lacking the p53 gene. For this study, 8-week-old C57BL/6 mice [WT and p53 knockout (KO)] were administered a benzene solution (150 mg/kg diluted in corn oil) via oral gavage once daily, 5 days/week, for 1 or 2 weeks. Blood and bone marrow cells were collected and cell counts were measured using a Coulter counter. Total mRNA and protein extracts were prepared from the harvested bone marrow cells. Then qRT-PCR and Western blotting were performed to detect changes in the caspases at the mRNA and protein level, respectively. A DNA fragmentation assay and Annexin-V staining were carried out on the bone marrow cells to detect apoptosis. Results indicated that when compared to the control, leukocyte number and bone marrow cellularity decreased significantly in WT mice. The expression of caspase-4 and -12 mRNA increased significantly after 12 days of benzene treatment in the bone marrow cells of benzene-exposed p53KO mice. However, apoptosis detection assays indicated no evidence of apoptosis in p53KO or WT mice. In addition, no changes of other apoptosis-related caspases, such as caspase-3 and -9, were found in WT or p53KO mice at the

  1. Lack of the sodium-driven chloride bicarbonate exchanger NCBE impairs visual function in the mouse retina.

    Directory of Open Access Journals (Sweden)

    Gerrit Hilgen

    Full Text Available Regulation of ion and pH homeostasis is essential for normal neuronal function. The sodium-driven chloride bicarbonate exchanger NCBE (Slc4a10, a member of the SLC4 family of bicarbonate transporters, uses the transmembrane gradient of sodium to drive cellular net uptake of bicarbonate and to extrude chloride, thereby modulating both intracellular pH (pH(i and chloride concentration ([Cl(-](i in neurons. Here we show that NCBE is strongly expressed in the retina. As GABA(A receptors conduct both chloride and bicarbonate, we hypothesized that NCBE may be relevant for GABAergic transmission in the retina. Importantly, we found a differential expression of NCBE in bipolar cells: whereas NCBE was expressed on ON and OFF bipolar cell axon terminals, it only localized to dendrites of OFF bipolar cells. On these compartments, NCBE colocalized with the main neuronal chloride extruder KCC2, which renders GABA hyperpolarizing. NCBE was also expressed in starburst amacrine cells, but was absent from neurons known to depolarize in response to GABA, like horizontal cells. Mice lacking NCBE showed decreased visual acuity and contrast sensitivity in behavioral experiments and smaller b-wave amplitudes and longer latencies in electroretinograms. Ganglion cells from NCBE-deficient mice also showed altered temporal response properties. In summary, our data suggest that NCBE may serve to maintain intracellular chloride and bicarbonate concentration in retinal neurons. Consequently, lack of NCBE in the retina may result in changes in pH(i regulation and chloride-dependent inhibition, leading to altered signal transmission and impaired visual function.

  2. Tetranectin Knockout Mice Develop Features of Parkinson Disease

    Directory of Open Access Journals (Sweden)

    Er-song Wang

    2014-07-01

    Full Text Available Background/Aims: Aggregation of insoluble α-synuclein to form Lewy bodies (LBs may contribute to the selective loss of midbrain dopaminergic neurons in Parkinson disease (PD. Lack of robust animal models has impeded elucidation of the molecular mechanisms of LB formation and other critical aspects of PD pathogenesis. Methods: We established a mouse model with targeted deletion of the plasminogen-binding protein tetranectin (TN gene (TN-/- and measured the behavioral and histopathological features of PD. Results: Aged (15-to 20-month-old TN-/- mice displayed motor deficits resembling PD symptoms, including limb rigidity and both slower ambulation (bradykinesia and reduced rearing activity in the open field. In addition, these mice exhibited more numerous α-synuclein-positive LB-like inclusions within the substantia nigra pars compacta (SNc and reduced numbers of SNc dopaminergic neurons than age-matched wild type (WT mice. These pathological changes were also accompanied by loss of dopamine terminals in the dorsal striatum. Conclusion: The TN-/- mouse exhibits several key features of PD and so may be a valuable model for studying LB formation and testing candidate neuroprotective therapies for PD and other synucleinopathies.

  3. Inhibition of tumor growth in syngenetic chimeric mice mediated by a depletion of suppressor T cells

    International Nuclear Information System (INIS)

    Rotter, V.; Trainin, N.

    1975-01-01

    Syngeneic chimeric (lethally irradiated and reconstituted with syngeneic bone marrow cells) mice manifested an increased resistance to the development of Lewis lung carcinoma. In addition, these mice had a higher response to polyvinylpyrrolidone and a reduced reactivity to T mitogens. The present findings suggest that syngeneic chimeric mice lack suppressor T cells shown to regulate the development of Lewis lung tumor and the response to polyvinylpyrrolidone. Other components of the T cell population, such as helper cells responding to sheep red blood cells or cells involved in allograft rejection, assayed in these syngeneic chimeras were found unaffected. The fact that chimeric mice are deficient in a certain suppressor T cell population whereas other T activities are normal suggests the existence of different cell lines within the T cell population. (U.S.)

  4. Carrageenan-Induced Colonic Inflammation Is Reduced in Bcl10 Null Mice and Increased in IL-10-Deficient Mice

    Directory of Open Access Journals (Sweden)

    Sumit Bhattacharyya

    2013-01-01

    Full Text Available The common food additive carrageenan is a known activator of inflammation in mammalian tissues and stimulates both the canonical and noncanonical pathways of NF-κB activation. Exposure to low concentrations of carrageenan (10 μg/mL in the water supply has produced glucose intolerance, insulin resistance, and impaired insulin signaling in C57BL/6 mice. B-cell leukemia/lymphoma 10 (Bcl10 is a mediator of inflammatory signals from Toll-like receptor (TLR 4 in myeloid and epithelial cells. Since the TLR4 signaling pathway is activated in diabetes and by carrageenan, we addressed systemic and intestinal inflammatory responses following carrageenan exposure in Bcl10 wild type, heterozygous, and null mice. Fecal calprotectin and circulating keratinocyte chemokine (KC, nuclear RelA and RelB, phospho(Thr559-NF-κB-inducing kinase (NIK, and phospho(Ser36-IκBα in the colonic epithelial cells were significantly less (P<0.001 in the carrageenan-treated Bcl10 null mice than in controls. IL-10-deficient mice exposed to carrageenan in a germ-free environment showed an increase in activation of the canonical pathway of NF-κB (RelA activation, but without increase in RelB or phospho-Bcl10, and exogenous IL-10 inhibited only the canonical pathway of NF-κB activation in cultured colonic cells. These findings demonstrate a Bcl10 requirement for maximum development of carrageenan-induced inflammation and lack of complete suppression by IL-10 of carrageenan-induced inflammation.

  5. Pervasive and stochastic changes in the TCR repertoire of regulatory T-cell-deficient mice.

    Science.gov (United States)

    Zheng, Lingjie; Sharma, Rahul; Kung, John T; Deshmukh, Umesh S; Jarjour, Wael N; Fu, Shu Man; Ju, Shyr-Te

    2008-04-01

    We hypothesize that regulatory T-cell (Treg)-deficient strains have an altered TCR repertoire in part due to the expansion of autoimmune repertoire by self-antigen. We compared the Vbeta family expression profile between B6 and Treg-lacking B6.Cg-Foxp3(sf)(/Y) (B6.sf) mice using fluorescent anti-Vbeta mAbs and observed no changes. However, while the spectratypes of 20 Vbeta families among B6 mice were highly similar, the Vbeta family spectratypes of B6.sf mice were remarkably different from B6 mice and from each other. Significant spectratype changes in many Vbeta families were also observed in Treg-deficient IL-2 knockout (KO) and IL-2Ralpha KO mice. Such changes were not observed with anti-CD3 mAb-treated B6 mice or B6 CD4+CD25- T cells. TCR transgenic (OT-II.sf) mice displayed dramatic reduction of clonotypic TCR with concomitant increase in T cells bearing non-transgenic Vbeta and Valpha families, including T cells with dual receptors expressing reduced levels of transgenic Valpha and endogenous Valpha. Collectively, the data demonstrate that Treg deficiency allows polyclonal expansion of T cells in a stochastic manner, resulting in widespread changes in the TCR repertoire.

  6. Adaptive gene regulation in the Striatum of RGS9-deficient mice.

    Directory of Open Access Journals (Sweden)

    Kathy Busse

    Full Text Available BACKGROUND: RGS9-deficient mice show drug-induced dyskinesia but normal locomotor activity under unchallenged conditions. RESULTS: Genes related to Ca2+ signaling and their functions were regulated in RGS9-deficient mice. CONCLUSION: Changes in Ca2+ signaling that compensate for RGS9 loss-of-function can explain the normal locomotor activity in RGS9-deficient mice under unchallenged conditions. SIGNIFICANCE: Identified signaling components may represent novel targets in antidyskinetic therapy. The long splice variant of the regulator of G-protein signaling 9 (RGS9-2 is enriched in striatal medium spiny neurons and dampens dopamine D2 receptor signaling. Lack of RGS9-2 can promote while its overexpression prevents drug-induced dyskinesia. Other animal models of drug-induced dyskinesia rather pointed towards overactivity of dopamine receptor-mediated signaling. To evaluate changes in signaling pathways mRNA expression levels were determined and compared in wild-type and RGS9-deficient mice. Unexpectedly, expression levels of dopamine receptors were unchanged in RGS9-deficient mice, while several genes related to Ca2+ signaling and long-term depression were differentially expressed when compared to wild type animals. Detailed investigations at the protein level revealed hyperphosphorylation of DARPP32 at Thr34 and of ERK1/2 in striata of RGS9-deficient mice. Whole cell patch clamp recordings showed that spontaneous synaptic events are increased (frequency and size in RGS9-deficient mice while long-term depression is reduced in acute brain slices. These changes are compatible with a Ca2+-induced potentiation of dopamine receptor signaling which may contribute to the drug-induced dyskinesia in RGS9-deficient mice.

  7. Preferences of group-housed female mice regarding structure of softwood bedding.

    Science.gov (United States)

    Kirchner, J; Hackbarth, H; Stelzer, H D; Tsai, P-P

    2012-04-01

    Bedding influences various parameters in the housing of laboratory mice, such as health, physiology and behaviour (often considered as being integral parts of welfare). Notwithstanding existent studies about bedding preferences of individually tested mice, data about group-housed mice are still lacking. The aim of this study was to find out the structure preference for softwood bedding of group-housed mice. One hundred and eight 8-week-old female mice (C57BL6/JOlaHsd and BALB/cOlaHsd) were housed in groups of three and were given one-week free access to two different bedding structures at a time. In three test combinations, softwood shaving bedding was tested versus softwood chip bedding products of three different particle sizes (fine/medium/coarse-grained). The preference test was performed in a DoubleCage system composed of two Makrolon type IIL cages, connected by a perspex tunnel. This validated system was able to detect the crossings of each individual animal with correct crossing time and direction. On the basis of these data, dwelling times on the particular bedding structures were statistically analysed as a parameter for bedding preferences. In all three test combinations, a highly significant shaving preference was detected. On average, mice spent 70% of their dwelling time on the shavings. This preference was more explicit during the light period and in C57BL/6J mice. The relative ranking of the bedding structures was: shavings > coarse-grained chips > medium chips = fine chips. By means of these results, a shaving structure as bedding can be recommended for laboratory mice, whereas fine chip structures should be avoided.

  8. Repair of uv damaged DNA in systemic lupus erythematosus. [Mice

    Energy Technology Data Exchange (ETDEWEB)

    Beighlie, D J; Teplitz, R L

    1975-06-01

    The NZB NZW hybrid mouse is an animal model of human systemic lupus erythematosus (SLE). Two breeding schemes were devised using NZB, NZW, B/W, and CBA mice, which permit definitive decisions regarding genetic and/or viral origin of the disease. It is proposed that at least two factors must be involved: a genetic abnormality producing hyper-responsiveness to nucleic acid antigens, and a DNA repair defect which results in liberation of DNA and RNA when cells are lethally injured. Evidence is presented for a DNA repair deficit in human SLE lymphocytes following in vitro irradiation with ultraviolet (uv) light. Lymphocytes from adult New Zealand and control mice were found to lack normal amounts of endonuclease necessary for repairing uv damage.

  9. Platelet serotonin promotes the recruitment of neutrophils to sites of acute inflammation in mice

    Science.gov (United States)

    Suidan, Georgette L.; Demers, Melanie; Herr, Nadine; Carbo, Carla; Brill, Alexander; Cifuni, Stephen M.; Mauler, Maximilian; Cicko, Sanja; Bader, Michael; Idzko, Marco; Bode, Christoph

    2013-01-01

    The majority of peripheral serotonin is stored in platelets, which secrete it on activation. Serotonin releases Weibel-Palade bodies (WPBs) and we asked whether absence of platelet serotonin affects neutrophil recruitment in inflammatory responses. Tryptophan hydroxylase (Tph)1–deficient mice, lacking non-neuronal serotonin, showed mild leukocytosis compared with wild-type (WT), primarily driven by an elevated neutrophil count. Despite this, 50% fewer leukocytes rolled on unstimulated mesenteric venous endothelium of Tph1−/− mice. The velocity of rolling leukocytes was higher in Tph1−/− mice, indicating fewer selectin-mediated interactions with endothelium. Stimulation of endothelium with histamine, a secretagogue of WPBs, or injection of serotonin normalized the rolling in Tph1−/− mice. Diminished rolling in Tph1−/− mice resulted in reduced firm adhesion of leukocytes after lipopolysaccharide treatment. Blocking platelet serotonin uptake with fluoxetine in WT mice reduced serum serotonin by > 80% and similarly reduced leukocyte rolling and adhesion. Four hours after inflammatory stimulation, neutrophil extravasation into lung, peritoneum, and skin wounds was reduced in Tph1−/− mice, whereas in vitro neutrophil chemotaxis was independent of serotonin. Survival of lipopolysaccharide-induced endotoxic shock was improved in Tph1−/− mice. In conclusion, platelet serotonin promotes the recruitment of neutrophils in acute inflammation, supporting an important role for platelet serotonin in innate immunity. PMID:23243271

  10. Deletion of vanilloid receptor (TRPV1) in mice alters behavioral effects of ethanol

    Science.gov (United States)

    Blednov, Y.A.; Harris, R.A.

    2009-01-01

    The vanilloid receptor TRPV1 is activated by ethanol and this may be important for some of the central and peripheral actions of ethanol. To determine if this receptor has a role in ethanol-mediated behaviors, we studied null mutant mice in which the Trpv1 gene was deleted. Mice lacking this gene showed significantly higher preference for ethanol and consumed more ethanol in a two-bottle choice test as compared with wild type littermates. Null mutant mice showed shorter duration of loss of righting reflex induced by low doses of ethanol (3.2 and 3.4 g/kg) and faster recovery from motor incoordination induced by ethanol (2 g/kg). However, there were no differences between null mutant and wild type mice in severity of ethanol-induced acute withdrawal (4 g/kg) or conditioned taste aversion to ethanol (2.5 g/kg). Two behavioral phenotypes (decreased sensitivity to ethanol-induced sedation and faster recovery from ethanol-induced motor incoordination) seen in null mutant mice were reproduced in wild type mice by injection of a TRPV1 antagonist, capsazepine (10 mg/kg). These two ethanol behaviors were changed in the opposite direction after injection of capsaicin, a selective TRPV1 agonist, in wild type mice. The studies provide the first evidence that TRPV1 is important for specific behavioral actions of ethanol. PMID:19705551

  11. Extensive immune-mediated hippocampal damage in mice surviving infection with neuroadapted Sindbis virus

    International Nuclear Information System (INIS)

    Kimura, Takashi; Griffin, Diane E.

    2003-01-01

    Viral infections of the central nervous system and immune responses to these infections cause a variety of neurological diseases. Infection of weanling mice with Sindbis virus causes acute nonfatal encephalomyelitis followed by clearance of infectious virus, but persistence of viral RNA. Infection with a neuroadapted strain of Sindbis virus (NSV) causes fatal encephalomyelitis, but passive transfer of immune serum after infection protects from fatal disease and infectious virus is cleared. To determine whether persistent NSV RNA is associated with neurological damage, we examined the brains of recovered mice and found progressive loss of the hippocampal gyrus, adjacent white matter, and deep cerebral cortex associated with mononuclear cell infiltration. Mice deficient in CD4 + T cells showed less tissue loss, while mice lacking CD8 + T cells showed lesions comparable to those in immunocompetent mice. Mice deficient in both CD4 + and CD8 + T cells developed severe tissue loss similar to immunocompetent mice and this was associated with extensive infiltration of macrophages. The number of CD4 + cells and macrophage/microglial cells, but not CD8 + cells, infiltrating the hippocampal gyrus was correlated with the number of terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling positive pyramidal neurons. These results suggest that CD4 + T cells can promote progressive neuronal death and tissue injury, despite clearance of infectious virus

  12. The role of p38 in mitochondrial respiration in male and female mice.

    Science.gov (United States)

    Ju, Xiaohua; Wen, Yi; Metzger, Daniel; Jung, Marianna

    2013-06-07

    p38 is a mitogen-activated protein kinase and mediates cell growth, cell differentiation, and synaptic plasticity. The aim of this study is to determine the extent to which p38 plays a role in maintaining mitochondrial respiration in male and female mice under a normal condition. To achieve this aim, we have generated transgenic mice that lack p38 in cerebellar Purkinje neurons by crossing Pcp2 (Purkinje cell protein 2)-Cre mice with p38(loxP/loxP) mice. Mitochondria from cerebellum were then isolated from the transgenic and wild-type mice to measure mitochondrial respiration using XF24 respirometer. The mRNA and protein expression of cytochrome c oxidase (COX) in cerebellum were also measured using RT-PCR and immunoblot methods. Separately, HT22 cells were used to determine the involvement of 17β-estradiol (E2) and COX in mitochondrial respiration. The genetic knockout of p38 in Purkinje neurons suppressed the mitochondrial respiration only in male mice and increased COX expression only in female mice. The inhibition of COX by sodium azide (SA) sharply suppressed mitochondrial respiration of HT22 cells in a manner that was protected by E2. These data suggest that p38 is required for the mitochondrial respiration of male mice. When p38 is below a normal level, females may maintain mitochondrial respiration through COX up-regulation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Insulin resistance for glucose metabolism in disused soleus muscle of mice

    Science.gov (United States)

    Seider, M. J.; Nicholson, W. F.; Booth, F. W.

    1981-01-01

    Results of this study on mice provide the first direct evidence of insulin resistance for glucose metabolism in skeletal muscle that has undergone a previous period of reduced muscle usage. This lack of responsiveness to insulin developed in one day and in the presence of hypoinsulinemia. Future studies will utilize the model of hindlimb immobilization to determine the causes of these changes.

  14. Methylprednisolone acetate induces, and Δ7-dafachronic acid suppresses, Strongyloides stercoralis hyperinfection in NSG mice.

    Science.gov (United States)

    Patton, John B; Bonne-Année, Sandra; Deckman, Jessica; Hess, Jessica A; Torigian, April; Nolan, Thomas J; Wang, Zhu; Kliewer, Steven A; Durham, Amy C; Lee, James J; Eberhard, Mark L; Mangelsdorf, David J; Lok, James B; Abraham, David

    2018-01-02

    Strongyloides stercoralis hyperinfection causes high mortality rates in humans, and, while hyperinfection can be induced by immunosuppressive glucocorticoids, the pathogenesis remains unknown. Since immunocompetent mice are resistant to infection with S. stercoralis , we hypothesized that NSG mice, which have a reduced innate immune response and lack adaptive immunity, would be susceptible to the infection and develop hyperinfection. Interestingly, despite the presence of large numbers of adult and first-stage larvae in S. stercoralis -infected NSG mice, no hyperinfection was observed even when the mice were treated with a monoclonal antibody to eliminate residual granulocyte activity. NSG mice were then infected with third-stage larvae and treated for 6 wk with methylprednisolone acetate (MPA), a synthetic glucocorticoid. MPA treatment of infected mice resulted in 50% mortality and caused a significant >10-fold increase in the number of parasitic female worms compared with infected untreated mice. In addition, autoinfective third-stage larvae, which initiate hyperinfection, were found in high numbers in MPA-treated, but not untreated, mice. Remarkably, treatment with Δ7-dafachronic acid, an agonist of the parasite nuclear receptor Ss -DAF-12, significantly reduced the worm burden in MPA-treated mice undergoing hyperinfection with S. stercoralis Overall, this study provides a useful mouse model for S. stercoralis autoinfection and suggests a therapeutic strategy for treating lethal hyperinfection.

  15. Mutations that affect meiosis in male mice influence the dynamics of the mid-preleptotene and bouquet stages

    International Nuclear Information System (INIS)

    Liebe, B.; Petukhova, G.; Barchi, M.; Bellani, M.; Braselmann, H.; Nakano, T.; Pandita, T.K.; Jasin, M.; Fornace, A.; Meistrich, M.L.; Baarends, W.M.; Schimenti, J.; Lange, T. de; Keeney, S.; Camerini-Otero, R.D.; Scherthan, H.

    2006-01-01

    Meiosis pairs and segregates homologous chromosomes and thereby forms haploid germ cells to compensate the genome doubling at fertilization. Homologue pairing in many eukaryotic species depends on formation of DNA double strand breaks (DSBs) during early prophase I when telomeres begin to cluster at the nuclear periphery (bouquet stage). By fluorescence in situ hybridization criteria, we observe that mid-preleptotene and bouquet stage frequencies are altered in male mice deficient for proteins required for recombination, ubiquitin conjugation and telomere length control. The generally low frequencies of mid-preleptotene spermatocytes were significantly increased in male mice lacking recombination proteins SPO11, MEI1, MLH1, KU80, ubiquitin conjugating enzyme HR6B, and in mice with only one copy of the telomere length regulator Terf1. The bouquet stage was significantly enriched in Atm -/- , Spo11 -/- , Mei1 m1Jcs/m1Jcs , Mlh1 -/- , Terf1 +/- and Hr6b -/- spermatogenesis, but not in mice lacking recombination proteins DMC1 and HOP2, the non-homologous end-joining DNA repair factor KU80 and the ATM downstream effector GADD45a. Mice defective in spermiogenesis (Tnp1 -/- , Gmcl1 -/- , Asm -/- ) showed wild-type mid-preleptotene and bouquet frequencies. A low frequency of bouquet spermatocytes in Spo11 -/- Atm -/- spermatogenesis suggests that DSBs contribute to the Atm -/- -correlated bouquet stage exit defect. Insignificant changes of bouquet frequencies in mice with defects in early stages of DSB repair (Dmc1 -/- , Hop2 -/- ) suggest that there is an ATM-specific influence on bouquet stage duration. Altogether, it appears that several pathways influence telomere dynamics in mammalian meiosis

  16. Cannabinoid 2 Receptor Agonist Improves Systemic Sensitivity to Insulin in High-Fat Diet/Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Xiuyuan Zhang

    2016-12-01

    Full Text Available Background/Aims: The endocannabinoid signalling (ECS system has been known to regulate glucose homeostasis. Previous studies have suggested that the cannabinoid 2 (CB2 receptor may play a regulatory role on insulin secretion, immune modulation and insulin resistance. Given that diabetes and insulin resistance are attributable to elevated inflammatory tone, we investigated the role of CB2 receptor on glucose tolerance and insulin sensitivity in high-fat diet (HFD/streptozotocin (STZ-induced mice. Methods: Diabetes was induced in male ICR mice by HFD/STZ and exposed to a CB2 receptor agonist, SER601, for 2- or 4-weeks via subcutaneous implantation of osmotic minipumps. Glucose and insulin tolerance tests were performed at the end of treatment. Islets were isolated for assessment of β-cell function. Pancreases and skeletal muscles were also obtained for histological analyses. Results: Despite a lack of impact on glucose tolerance, substantial improvement on insulin sensitivity was observed in SER601-treated mice, which could partly be attributed to improved islet β-cell function, shown as increased glucose-induced insulin secretion and insulin content. No changes on islet macrophage infiltration or skeletal muscle fat deposition were detectable from SER601-treated mice. However, a major decrease in body weight was recorded at the end of 4-week SER601 exposure, accompanied by a lack of epididymal adipose mass in SER601-treated mice. Conclusion: Our data suggest a lipolytic role of SER601 in HFD/STZ-induced diabetic mice, which results in significant improvement of systemic insulin sensitivity. Thus, the CB2 receptor may be considered a promising target for therapeutic development against insulin resistance and obesity-related diabetes.

  17. TAM receptor knockout mice are susceptible to retinal autoimmune induction.

    Science.gov (United States)

    Ye, Fei; Li, Qiutang; Ke, Yan; Lu, Qingjun; Han, Lixia; Kaplan, Henry J; Shao, Hui; Lu, Qingxian

    2011-06-16

    TAM receptors are expressed mainly by dendritic cells and macrophages in the immune system, and mice lacking TAM receptors develop systemic autoimmune diseases because of inefficient negative control of the cytokine signaling in those cells. This study aims to test the susceptibility of the TAM triple knockout (tko) mice to the retina-specific autoantigen to develop experimental autoimmune uveoretinitis (EAU). TAM tko mice that were or were not immunized with interphotoreceptor retinoid-binding protein (IRBP) peptides were evaluated for retinal infiltration of the macrophages and CD3(+) T cells by immunohistochemistry, spontaneous activation of CD4(+) T cells, and memory T cells by flow cytometry and proliferation of IRBP-specific CD4(+) T cells by [(3)H]thymidine incorporation assay. Ocular inflammation induced by IRBP peptide immunization and specific T cell transfer were observed clinically by funduscopy and confirmed by histology. Tko mice were found to have less naive, but more activated, memory T cells, among which were exhibited high sensitivity to ocular IRBP autoantigens. Immunization with a low dose of IRBP and adoptive transfer of small numbers of IRBP-specific T cells from immunized tko mice caused the infiltration of lymphocytes, including CD3(+) T cells, into the tko retina. Mice without TAM receptor spontaneously develop IRBP-specific CD4(+) T cells and are more susceptible to retinal autoantigen immunization. This TAM knockout mouse line provides an animal model with which to study the role of antigen-presenting cells in the development of T cell-mediated uveitis.

  18. Lack of macrophage migration inhibitory factor in mice does not affect hallmarks of the inflammatory/immune response during the first week after stroke

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    Deierborg Tomas

    2011-06-01

    Full Text Available Abstract Background Macrophage migration inhibitory factor (MIF has been proposed to play a detrimental role in stroke. We recently showed that MIF promotes neuronal death and aggravates neurological deficits during the first week after experimental stroke, in mice. Since MIF regulates tissue inflammation, we studied the putative role of MIF in post-stroke inflammation. Methods We subjected C57BL/6 mice, Mif-/- (MIF-KO or Mif+/+ (WT, to a transient occlusion of the right middle cerebral artery (tMCAo or sham-surgery. We studied MIF expression, GFAP expression and the number of CD74-positive cells in the ischemic brain hemisphere 7 days after tMCAo using primarily immunohistochemistry. We determined IFN-γ, IL-2, IL-4, IL-5, IL-10, IL-12, KC/CXCL-1 and TNF-α protein levels in the brain (48 h after surgery and serum (48 h and 7 days after surgery by a multiplex immunoassay. Results We observed that MIF accumulates in neurons and astrocytes of the peri-infarct region, as well as in microglia/macrophages of the infarct core up to 7 days after stroke. Among the inflammatory mediators analyzed, we found a significant increase in cerebral IL-12 and KC levels after tMCAo, in comparison to sham-surgery. Importantly, the deletion of Mif did not significantly affect the levels of the cytokines evaluated, in the brain or serum. Moreover, the spleen weight 48 h and 7 days subsequent to tMCAo was similar in WT and MIF-KO mice. Finally, the extent of GFAP immunoreactivity and the number of MIF receptor (CD74-positive cells within the ischemic brain hemisphere did not differ significantly between WT and MIF-KO mice subjected to tMCAo. Conclusions We conclude that MIF does not affect major components of the inflammatory/immune response during the first week after experimental stroke. Based on present and previous evidence, we propose that the deleterious MIF-mediated effects in stroke depend primarily on an intraneuronal and/or interneuronal action.

  19. Female Mice Deficient in Alpha-Fetoprotein Show Female-Typical Neural Responses to Conspecific-Derived Pheromones

    NARCIS (Netherlands)

    Brock, O.; Keller, M.; Douhard, Q.; Bakker, J.

    2012-01-01

    The neural mechanisms controlling sexual behavior are sexually differentiated by the perinatal actions of sex steroid hormones. We recently observed using female mice deficient in alpha-fetoprotein (AFP-KO) and which lack the protective actions of AFP against maternal estradiol, that exposure to

  20. Lethal Zika Virus Disease Models in Young and Older Interferon α/β Receptor Knock Out Mice

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    Andrea Marzi

    2018-04-01

    Full Text Available The common small animal disease models for Zika virus (ZIKV are mice lacking the interferon responses, but infection of interferon receptor α/β knock out (IFNAR−/− mice is not uniformly lethal particularly in older animals. Here we sought to advance this model in regard to lethality for future countermeasure efficacy testing against more recent ZIKV strains from the Asian lineage, preferably the American sublineage. We first infected IFNAR−/− mice subcutaneously with the contemporary ZIKV-Paraiba strain resulting in predominantly neurological disease with ~50% lethality. Infection with ZIKV-Paraiba by different routes established a uniformly lethal model only in young mice (4-week old upon intraperitoneal infection. However, intraperitoneal inoculation of ZIKV-French Polynesia resulted in uniform lethality in older IFNAR−/− mice (10–12-weeks old. In conclusion, we have established uniformly lethal mouse disease models for efficacy testing of antivirals and vaccines against recent ZIKV strains representing the Asian lineage.

  1. Chronic subordination stress induces hyperphagia and disrupts eating behavior in mice modeling binge-eating-like disorder

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    Maria eRazzoli

    2015-01-01

    Full Text Available Background: Eating disorders are associated with physical morbidity and appear to have causal factors like stressful life events and negative affect. Binge eating disorder (BED is characterized by eating in a discrete period of time a larger than normal amount of food, a sense of lack of control over eating, and marked distress. There are still unmet needs for the identification of mechanisms regulating excessive eating, which is in part due to the lack of appropriate animal models. We developed a naturalistic murine model of subordination stress induced hyperphagia associated with the development of obesity. Here we tested the hypotheses that the eating responses of subordinate mice recapitulate the BED and that limiting hyperphagia could prevent stress-associated metabolic changes. Methods: Adult male mice were exposed to a model of chronic subordination stress associated with the automated acquisition of food intake and we performed a detailed meal pattern analysis. Additionally, using a pair-feeding protocol was test the hypothesis that the manifestation of obesity and the metabolic syndrome could be prevented by limiting hyperphagia. Results: The architecture of feeding of subordinate mice was disrupted during the stress protocol due to disproportionate amount of food ingested at higher rate and with shorter satiety ratio than control mice. Subordinate mice hyperphagia was further exacerbated in response to either hunger or to the acute application of a social defeat. Notably, the obese phenotype but not the fasting hyperglycemia of subordinate mice was abrogated by preventing hyperphagia in a pair feeding paradigm. Conclusion: Overall these results support the validity of our chronic subordination stress to model binge eating disorder allowing for the determination of the underlying molecular mechanisms and the generation of testable predictions for innovative therapies, based on the understanding of the regulation and the control of food

  2. SnoRNA Snord116 (Pwcr1/MBII-85 deletion causes growth deficiency and hyperphagia in mice.

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    Feng Ding

    Full Text Available Prader-Willi syndrome (PWS is the leading genetic cause of obesity. After initial severe hypotonia, PWS children become hyperphagic and morbidly obese, if intake is not restricted. Short stature with abnormal growth hormone secretion, hypogonadism, cognitive impairment, anxiety and behavior problems are other features. PWS is caused by lack of expression of imprinted genes in a approximately 4 mb region of chromosome band 15q11.2. Our previous translocation studies predicted a major role for the C/D box small nucleolar RNA cluster SNORD116 (PWCR1/HBII-85 in PWS. To test this hypothesis, we created a approximately 150 kb deletion of the > 40 copies of Snord116 (Pwcr1/MBII-85 in C57BL/6 mice. Snord116del mice with paternally derived deletion lack expression of this snoRNA. They have early-onset postnatal growth deficiency, but normal fertility and lifespan. While pituitary structure and somatotrophs are normal, liver Igf1 mRNA is decreased. In cognitive and behavior tests, Snord116del mice are deficient in motor learning and have increased anxiety. Around three months of age, they develop hyperphagia, but stay lean on regular and high-fat diet. On reduced caloric intake, Snord116del mice maintain their weight better than wild-type littermates, excluding increased energy requirement as a cause of hyperphagia. Normal compensatory feeding after fasting, and ability to maintain body temperature in the cold indicate normal energy homeostasis regulation. Metabolic chamber studies reveal that Snord116del mice maintain energy homeostasis by altered fuel usage. Prolonged mealtime and increased circulating ghrelin indicate a defect in meal termination mechanism. Snord116del mice, the first snoRNA deletion animal model, reveal a novel role for a non-coding RNA in growth and feeding regulation.

  3. Critical role of IFN-gamma in CFA-mediated protection of NOD mice from diabetes development.

    Science.gov (United States)

    Mori, Yoshiko; Kodaka, Tetsuro; Kato, Takako; Kanagawa, Edith M; Kanagawa, Osami

    2009-11-01

    IFN-gamma signaling-deficient non-obese diabetic (NOD) mice develop diabetes with similar kinetics to those of wild-type NOD mice. However, the immunization of IFN-gamma signaling-deficient NOD mice with CFA failed to induce long-term protection, whereas wild-type NOD mice receiving CFA remained diabetes-free. CFA also failed to protect IFN-gamma receptor-deficient (IFN-gammaR(-/-)) NOD mice from the autoimmune rejection of transplanted islets, as it does in diabetic NOD mice, and from disease transfer by spleen cells from diabetic NOD mice. These data clearly show that the pro-inflammatory cytokine IFN-gamma is necessary for the CFA-mediated protection of NOD mice from diabetes. There is no difference in the T(h)1/T(h)17 balance between IFN-gammaR(-/-) NOD and wild-type NOD mice. There is also no difference in the total numbers and percentages of regulatory T (Treg) cells in the lymph node CD4(+) T-cell populations between IFN-gammaR(-/-) NOD and wild-type NOD mice. However, pathogenic T cells lacking IFN-gammaR are resistant to the suppressive effect of Treg cells, both in vivo and in vitro. Therefore, it is likely that CFA-mediated protection against diabetes development depends on a change in the balance between Treg cells and pathogenic T cells, and IFN-gamma signaling seems to control the susceptibility of pathogenic T cells to the inhibitory activity of Treg cells.

  4. Effects of ascorbic acid on carcinogenicity and acute toxicity of nickel subsulfide, and on tumor transplants growth in gulonolactone oxidase knock-out mice and wild-type C57BL mice

    Energy Technology Data Exchange (ETDEWEB)

    Kasprzak, Kazimierz S. [Laboratory of Comparative Carcinogenesis, National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Diwan, Bhalchandra A. [Basic Research Program, Science Applications International Corporation-Frederick, Inc., National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Kaczmarek, Monika Z. [Laboratory of Comparative Carcinogenesis, National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Logsdon, Daniel L. [Laboratory Animal Sciences Program, Science Applications International Corporation-Frederick, Inc., National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Fivash, Mathew J. [Data Management Services, National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Salnikow, Konstantin, E-mail: salnikok@mail.nih.gov [Laboratory of Comparative Carcinogenesis, National Cancer Institute at Frederick, Frederick, MD 21702 (United States)

    2011-11-15

    The aim of this study was to test a hypothesis that ascorbate depletion could enhance carcinogenicity and acute toxicity of nickel. Homozygous L-gulono- < gamma > -lactone oxidase gene knock-out mice (Gulo-/- mice) unable to produce ascorbate and wild-type C57BL mice (WT mice) were injected intramuscularly with carcinogenic nickel subsulfide (Ni{sub 3}S{sub 2}), and observed for the development of injection site tumors for 57 weeks. Small pieces of one of the induced tumors were transplanted subcutaneously into separate groups of Gulo-/- and WT mice and the growth of these tumors was measured for up to 3 months. The two strains of mice differed significantly with regard to (1) Ni{sub 3}S{sub 2} carcinogenesis: Gulo-/- mice were 40% more susceptible than WT mice; and (2) transplanted tumors development: Gulo-/- mice were more receptive to tumor growth than WT mice, but only in terms of a much shorter tumor latency; later in the exponential phase of growth, the growth rates were the same. And, with adequate ascorbate supplementation, the two strains were equally susceptible to acute toxicity of Ni{sub 3}S{sub 2}. Statistically significant effects of dietary ascorbate dosing levels were the following: (1) reduction in ascorbate supplementation increased acute toxicity of Ni{sub 3}S{sub 2} in Gulo-/- mice; (2) ascorbate supplementation extended the latency of transplanted tumors in WT mice. In conclusion, the lack of endogenous ascorbate synthesis makes Gulo-/- mice more susceptible to Ni{sub 3}S{sub 2} carcinogenesis. Dietary ascorbate tends to attenuate acute toxicity of Ni{sub 3}S{sub 2} and to extend the latency of transplanted tumors. The latter effects may be of practical importance to humans and thus deserve further studies. -- Highlights: Black-Right-Pointing-Pointer Ascorbate depletion enhances carcinogenicity and acute toxicity of nickel. Black-Right-Pointing-Pointer Gulo-/- mice unable to synthesize ascorbate were used in this study. Black

  5. Effects of ascorbic acid on carcinogenicity and acute toxicity of nickel subsulfide, and on tumor transplants growth in gulonolactone oxidase knock-out mice and wild-type C57BL mice

    International Nuclear Information System (INIS)

    Kasprzak, Kazimierz S.; Diwan, Bhalchandra A.; Kaczmarek, Monika Z.; Logsdon, Daniel L.; Fivash, Mathew J.; Salnikow, Konstantin

    2011-01-01

    The aim of this study was to test a hypothesis that ascorbate depletion could enhance carcinogenicity and acute toxicity of nickel. Homozygous L-gulono- -lactone oxidase gene knock-out mice (Gulo−/− mice) unable to produce ascorbate and wild-type C57BL mice (WT mice) were injected intramuscularly with carcinogenic nickel subsulfide (Ni 3 S 2 ), and observed for the development of injection site tumors for 57 weeks. Small pieces of one of the induced tumors were transplanted subcutaneously into separate groups of Gulo−/− and WT mice and the growth of these tumors was measured for up to 3 months. The two strains of mice differed significantly with regard to (1) Ni 3 S 2 carcinogenesis: Gulo−/− mice were 40% more susceptible than WT mice; and (2) transplanted tumors development: Gulo−/− mice were more receptive to tumor growth than WT mice, but only in terms of a much shorter tumor latency; later in the exponential phase of growth, the growth rates were the same. And, with adequate ascorbate supplementation, the two strains were equally susceptible to acute toxicity of Ni 3 S 2 . Statistically significant effects of dietary ascorbate dosing levels were the following: (1) reduction in ascorbate supplementation increased acute toxicity of Ni 3 S 2 in Gulo−/− mice; (2) ascorbate supplementation extended the latency of transplanted tumors in WT mice. In conclusion, the lack of endogenous ascorbate synthesis makes Gulo−/− mice more susceptible to Ni 3 S 2 carcinogenesis. Dietary ascorbate tends to attenuate acute toxicity of Ni 3 S 2 and to extend the latency of transplanted tumors. The latter effects may be of practical importance to humans and thus deserve further studies. -- Highlights: ► Ascorbate depletion enhances carcinogenicity and acute toxicity of nickel. ► Gulo−/− mice unable to synthesize ascorbate were used in this study. ► The reduction in ascorbate levels in Gulo−/− mice increased acute toxicity induced by Ni 3 S 2 .

  6. Inducible targeting of CNS astrocytes in Aldh1l1-CreERT2 BAC transgenic mice.

    Science.gov (United States)

    Winchenbach, Jan; Düking, Tim; Berghoff, Stefan A; Stumpf, Sina K; Hülsmann, Swen; Nave, Klaus-Armin; Saher, Gesine

    2016-01-01

    Background: Studying astrocytes in higher brain functions has been hampered by the lack of genetic tools for the efficient expression of inducible Cre recombinase throughout the CNS, including the neocortex. Methods: Therefore, we generated BAC transgenic mice, in which CreERT2 is expressed under control of the Aldh1l1 regulatory region. Results: When crossbred to Cre reporter mice, adult Aldh1l1-CreERT2 mice show efficient gene targeting in astrocytes. No such Cre-mediated recombination was detectable in CNS neurons, oligodendrocytes, and microglia. As expected, Aldh1l1-CreERT2 expression was evident in several peripheral organs, including liver and kidney. Conclusions: Taken together, Aldh1l1-CreERT2 mice are a useful tool for studying astrocytes in neurovascular coupling, brain metabolism, synaptic plasticity and other aspects of neuron-glia interactions.

  7. Defective bone repair in mast cell-deficient Cpa3Cre/+ mice.

    Directory of Open Access Journals (Sweden)

    Jose Luis Ramirez-GarciaLuna

    Full Text Available In the adult skeleton, cells of the immune system interact with those of the skeleton during all phases of bone repair to influence the outcome. Mast cells are immune cells best known for their pathologic role in allergy, and may be involved in chronic inflammatory and fibrotic disorders. Potential roles for mast cells in tissue homeostasis, vascularization and repair remain enigmatic. Previous studies in combined mast cell- and Kit-deficient KitW-sh/W-sh mice (KitW-sh implicated mast cells in bone repair but KitW-sh mice suffer from additional Kit-dependent hematopoietic and non- hematopoietic deficiencies that could have confounded the outcome. The goal of the current study was to compare bone repair in normal wild type (WT and Cpa3Cre/+ mice, which lack mast cells in the absence of any other hematopoietic or non- hematopoietic deficiencies. Repair of a femoral window defect was characterized using micro CT imaging and histological analyses from the early inflammatory phase, through soft and hard callus formation, and finally the remodeling phase. The data indicate 1 mast cells appear in healing bone of WT mice but not Cpa3Cre/+ mice, beginning 14 days after surgery; 2 re-vascularization of repair tissue and deposition of mineralized bone was delayed and dis-organised in Cpa3Cre/+ mice compared with WT mice; 3 the defects in Cpa3Cre/+ mice were associated with little change in anabolic activity and biphasic alterations in osteoclast and macrophage activity. The outcome at 56 days postoperative was complete bridging of the defect in most WT mice and fibrous mal-union in most Cpa3Cre/+ mice. The results indicate that mast cells promote bone healing, possibly by recruiting vascular endothelial cells during the inflammatory phase and coordinating anabolic and catabolic activity during tissue remodeling. Taken together the data indicate that mast cells have a positive impact on bone repair.

  8. Defective bone repair in mast cell-deficient Cpa3Cre/+ mice.

    Science.gov (United States)

    Ramirez-GarciaLuna, Jose Luis; Chan, Daniel; Samberg, Robert; Abou-Rjeili, Mira; Wong, Timothy H; Li, Ailian; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Henderson, Janet E; Martineau, Paul A

    2017-01-01

    In the adult skeleton, cells of the immune system interact with those of the skeleton during all phases of bone repair to influence the outcome. Mast cells are immune cells best known for their pathologic role in allergy, and may be involved in chronic inflammatory and fibrotic disorders. Potential roles for mast cells in tissue homeostasis, vascularization and repair remain enigmatic. Previous studies in combined mast cell- and Kit-deficient KitW-sh/W-sh mice (KitW-sh) implicated mast cells in bone repair but KitW-sh mice suffer from additional Kit-dependent hematopoietic and non- hematopoietic deficiencies that could have confounded the outcome. The goal of the current study was to compare bone repair in normal wild type (WT) and Cpa3Cre/+ mice, which lack mast cells in the absence of any other hematopoietic or non- hematopoietic deficiencies. Repair of a femoral window defect was characterized using micro CT imaging and histological analyses from the early inflammatory phase, through soft and hard callus formation, and finally the remodeling phase. The data indicate 1) mast cells appear in healing bone of WT mice but not Cpa3Cre/+ mice, beginning 14 days after surgery; 2) re-vascularization of repair tissue and deposition of mineralized bone was delayed and dis-organised in Cpa3Cre/+ mice compared with WT mice; 3) the defects in Cpa3Cre/+ mice were associated with little change in anabolic activity and biphasic alterations in osteoclast and macrophage activity. The outcome at 56 days postoperative was complete bridging of the defect in most WT mice and fibrous mal-union in most Cpa3Cre/+ mice. The results indicate that mast cells promote bone healing, possibly by recruiting vascular endothelial cells during the inflammatory phase and coordinating anabolic and catabolic activity during tissue remodeling. Taken together the data indicate that mast cells have a positive impact on bone repair.

  9. Deletion of PEA-15 in mice is associated with specific impairments of spatial learning abilities

    Directory of Open Access Journals (Sweden)

    Hale Gregory

    2009-11-01

    Full Text Available Abstract Background PEA-15 is a phosphoprotein that binds and regulates ERK MAP kinase and RSK2 and is highly expressed throughout the brain. PEA-15 alters c-Fos and CREB-mediated transcription as a result of these interactions. To determine if PEA-15 contributes to the function of the nervous system we tested mice lacking PEA-15 in a series of experiments designed to measure learning, sensory/motor function, and stress reactivity. Results We report that PEA-15 null mice exhibited impaired learning in three distinct spatial tasks, while they exhibited normal fear conditioning, passive avoidance, egocentric navigation, and odor discrimination. PEA-15 null mice also had deficient forepaw strength and in limited instances, heightened stress reactivity and/or anxiety. However, these non-cognitive variables did not appear to account for the observed spatial learning impairments. The null mice maintained normal weight, pain sensitivity, and coordination when compared to wild type controls. Conclusion We found that PEA-15 null mice have spatial learning disabilities that are similar to those of mice where ERK or RSK2 function is impaired. We suggest PEA-15 may be an essential regulator of ERK-dependent spatial learning.

  10. Exploration, anxiety, and spatial memory in transgenic anophthalmic mice.

    Science.gov (United States)

    Buhot, M C; Dubayle, D; Malleret, G; Javerzat, S; Segu, L

    2001-04-01

    Contradictory results are found in the literature concerning the role of vision in the perception of space or in spatial navigation, in part because of the lack of murine models of total blindness used so far. The authors evaluated the spatial abilities of anophthalmic transgenic mice. These mice did not differ qualitatively from their wild-type littermates in general locomotor activity, spontaneous alternation, object exploration, or anxiety, but their level of exploratory activity was generally lower. In the spatial version of the water maze, they displayed persistent thigmotaxic behavior and showed severe spatial learning impairments. However, their performances improved with training, suggesting that they may have acquired a rough representation of the platform position. These results suggest that modalities other than vision enable some degree of spatial processing in proximal and structured spaces but that vision is critical for accurate spatial navigation.

  11. Histidine Decarboxylase Deficiency Prevents Autoimmune Diabetes in NOD Mice

    OpenAIRE

    Alkan , Manal; Machavoine , François; Rignault , Rachel; Dam , Julie; Dy , Michel; Thieblemont , Nathalie

    2015-01-01

    International audience; Recent evidence has highlighted the role of histamine in inflammation. Since this monoamine has also been strongly implicated in the pathogenesis of type-1 diabetes, we assessed its effect in the nonobese diabetic (NOD) mouse model. To this end, we used mice (inactivated) knocked out for the gene encoding histidine decarboxylase, the unique histamine-forming enzyme, backcrossed on a NOD genetic background. We found that the lack of endogenous histamine in NOD HDC −/− m...

  12. Mice Lacking Free Fatty Acid Receptor 1 (GPR40/FFAR1) are Protected Against Conjugated Linoleic Acid-Induced Fatty Liver but Develop Inflammation and Insulin Resistance in the Brain.

    Science.gov (United States)

    Sartorius, Tina; Drescher, Andrea; Panse, Madhura; Lastovicka, Petr; Peter, Andreas; Weigert, Cora; Kostenis, Evi; Ullrich, Susanne; Häring, Hans-Ulrich

    2015-01-01

    Conjugated linoleic acids (CLAs) affect body fat distribution, induce insulin resistance and stimulate insulin secretion. The latter effect is mediated through the free fatty acid receptor-1 (GPR40/FFAR1). This study examines whether GPR40/FFAR1 interacts with tissue specific metabolic changes induced by CLAs. After chronic application of CLAs C57BL/6J wild type (WT) and GPR40/FFAR1 (Ffar1(-/-)) knockout mice developed insulin resistance. Although CLAs accumulated in liver up to 46-fold genotype-independently, hepatic triglycerides augmented only in WT mice. This triglyceride deposition was not associated with increased inflammation. In contrast, in brain of CLA fed Ffar1(-/-) mice mRNA levels of TNF-α were 2-fold higher than in brain of WT mice although CLAs accumulated genotype-independently in brain up to 4-fold. Concomitantly, Ffar1(-/-) mice did not respond to intracerebroventricular (i.c.v.) insulin injection with an increase in cortical activity while WT mice reacted as assessed by radiotelemetric electrocorticography (ECoG) measurements. In vitro incubation of primary murine astrocytes confirmed that CLAs stimulate neuronal inflammation independent of GPR40/FFAR1. This study discloses that GPR40/FFAR1 indirectly modulates organ-specific effects of CLAs: the expression of functional GPR40/FFAR1 counteracts CLA-induced inflammation and insulin resistance in the brain, but favors the development of fatty liver. © 2015 S. Karger AG, Basel.

  13. Glutathione-S-transferase A3 knockout mice are sensitive to acute cytotoxic and genotoxic effects of aflatoxin B1

    International Nuclear Information System (INIS)

    Ilic, Zoran; Crawford, Dana; Egner, Patricia A.; Sell, Stewart

    2010-01-01

    Aflatoxin B1 (AFB1) is a major risk factor for hepatocellular carcinoma (HCC) in humans. However, mice, a major animal model for the study of AFB1 carcinogenesis, are resistant, due to high constitutive expression, in the mouse liver, of glutathione S-transferase A3 subunit (mGSTA3) that is lacking in humans. Our objective was to establish that a mouse model for AFB1 toxicity could be used to study mechanisms of toxicity that are relevant for human disease, i.e., an mGSTA3 knockout (KO) mouse that responds to toxicants such as AFB1 in a manner similar to humans. Exons 3-6 of the mGSTA3 were replaced with a neomycin cassette by homologous recombination. Southern blotting, RT-PCR, Western blotting, and measurement of AFB1-N 7 -DNA adduct formation were used to evaluate the mGSTA3 KO mice. The KO mice have deletion of exons 3-6 of the mGSTA3 gene, as expected, as well as a lack of mGSTA3 expression at the mRNA and protein levels. Three hours after injection of 5 mg/kg AFB1, mGSTA3 KO mice have more than 100-fold more AFB1-N 7 -DNA adducts in their livers than do similarly treated wild-type (WT) mice. In addition, the mGSTA3 KO mice die of massive hepatic necrosis, at AFB1 doses that have minimal toxic effects in WT mice. We conclude that mGSTA3 KO mice are sensitive to the acute cytotoxic and genotoxic effects of AFB1, confirming the crucial role of GSTA3 subunit in protection of normal mice against AFB1 toxicity. We propose the mGSTA3 KO mouse as a useful model with which to study the interplay of risk factors leading to HCC development in humans, as well as for testing of additional possible functions of mGSTA3.

  14. Loss of CDKL5 in Glutamatergic Neurons Disrupts Hippocampal Microcircuitry and Leads to Memory Impairment in Mice.

    Science.gov (United States)

    Tang, Sheng; Wang, I-Ting Judy; Yue, Cuiyong; Takano, Hajime; Terzic, Barbara; Pance, Katarina; Lee, Jun Y; Cui, Yue; Coulter, Douglas A; Zhou, Zhaolan

    2017-08-02

    Cyclin-dependent kinase-like 5 (CDKL5) deficiency is a neurodevelopmental disorder characterized by epileptic seizures, severe intellectual disability, and autistic features. Mice lacking CDKL5 display multiple behavioral abnormalities reminiscent of the disorder, but the cellular origins of these phenotypes remain unclear. Here, we find that ablating CDKL5 expression specifically from forebrain glutamatergic neurons impairs hippocampal-dependent memory in male conditional knock-out mice. Hippocampal pyramidal neurons lacking CDKL5 show decreased dendritic complexity but a trend toward increased spine density. This morphological change is accompanied by an increase in the frequency of spontaneous miniature EPSCs and interestingly, miniature IPSCs. Using voltage-sensitive dye imaging to interrogate the evoked response of the CA1 microcircuit, we find that CA1 pyramidal neurons lacking CDKL5 show hyperexcitability in their dendritic domain that is constrained by elevated inhibition in a spatially and temporally distinct manner. These results suggest a novel role for CDKL5 in the regulation of synaptic function and uncover an intriguing microcircuit mechanism underlying impaired learning and memory. SIGNIFICANCE STATEMENT Cyclin-dependent kinase-like 5 (CDKL5) deficiency is a severe neurodevelopmental disorder caused by mutations in the CDKL5 gene. Although Cdkl5 constitutive knock-out mice have recapitulated key aspects of human symptomatology, the cellular origins of CDKL5 deficiency-related phenotypes are unknown. Here, using conditional knock-out mice, we show that hippocampal-dependent learning and memory deficits in CDKL5 deficiency have origins in glutamatergic neurons of the forebrain and that loss of CDKL5 results in the enhancement of synaptic transmission and disruptions in neural circuit dynamics in a spatially and temporally specific manner. Our findings demonstrate that CDKL5 is an important regulator of synaptic function in glutamatergic neurons and

  15. Parasitic infection improves survival from septic peritonitis by enhancing mast cell responses to bacteria in mice.

    Directory of Open Access Journals (Sweden)

    Rachel E Sutherland

    Full Text Available Mammals are serially infected with a variety of microorganisms, including bacteria and parasites. Each infection reprograms the immune system's responses to re-exposure and potentially alters responses to first-time infection by different microorganisms. To examine whether infection with a metazoan parasite modulates host responses to subsequent bacterial infection, mice were infected with the hookworm-like intestinal nematode Nippostrongylus brasiliensis, followed in 2-4 weeks by peritoneal injection of the pathogenic bacterium Klebsiella pneumoniae. Survival from Klebsiella peritonitis two weeks after parasite infection was better in Nippostrongylus-infected animals than in unparasitized mice, with Nippostrongylus-infected mice having fewer peritoneal bacteria, more neutrophils, and higher levels of protective interleukin 6. The improved survival of Nippostrongylus-infected mice depends on IL-4 because the survival benefit is lost in mice lacking IL-4. Because mast cells protect mice from Klebsiella peritonitis, we examined responses in mast cell-deficient Kit(W-sh/Kit(W-sh mice, in which parasitosis failed to improve survival from Klebsiella peritonitis. However, adoptive transfer of cultured mast cells to Kit(W-sh/Kit(W-sh mice restored survival benefits of parasitosis. These results show that recent infection with Nippostrongylus brasiliensis protects mice from Klebsiella peritonitis by modulating mast cell contributions to host defense, and suggest more generally that parasitosis can yield survival advantages to a bacterially infected host.

  16. Development of electrocardiogram intervals during growth of FVB/N neonate mice

    Science.gov (United States)

    2010-01-01

    Background Electrocardiography remains the best diagnostic tool and therapeutic biomarker for a spectrum of pediatric diseases involving cardiac or autonomic nervous system defects. As genetic links to these disorders are established and transgenic mouse models produced in efforts to understand and treat them, there is a surprising lack of information on electrocardiograms (ECGs) and ECG abnormalities in neonate mice. This is likely due to the trauma and anaesthesia required of many legacy approaches to ECG recording in mice, exacerbated by the fragility of many mutant neonates. Here, we use a non-invasive system to characterize development of the heart rate and electrocardiogram throughout the growth of conscious neonate FVB/N mice. Results We examine ECG waveforms as early as two days after birth. At this point males and females demonstrate comparable heart rates that are 50% lower than adult mice. Neonatal mice exhibit very low heart rate variability. Within 12 days of birth PR, QRS and QTc interval durations are near adult values while heart rate continues to increase until weaning. Upon weaning FVB/N females quickly develop slower heart rates than males, though PR intervals are comparable between sexes until a later age. This suggests separate developmental events may contribute to these gender differences in electrocardiography. Conclusions We provide insight with a new level of detail to the natural course of heart rate establishment in neonate mice. ECG can now be conveniently and repeatedly used in neonatal mice. This should serve to be of broad utility, facilitating further investigations into development of a diverse group of diseases and therapeutics in preclinical mouse studies. PMID:20735846

  17. Developmental consequences of in utero sodium arsenate exposure in mice with folate transport deficiencies

    International Nuclear Information System (INIS)

    Spiegelstein, Ofer; Gould, Amy; Wlodarczyk, Bogdan; Tsie, Marlene; Lu Xiufen; Le, Chris; Troen, Aron; Selhub, Jacob; Piedrahita, Jorge A.; Salbaum, J. Michael; Kappen, Claudia; Melnyk, Stepan; James, Jill; Finnell, Richard H.

    2005-01-01

    Previous studies have demonstrated that mice lacking a functional folate binding protein 2 gene (Folbp2 -/- ) were significantly more sensitive to in utero arsenic exposure than were the wild-type mice similarly exposed. When these mice were fed a folate-deficient diet, the embryotoxic effect of arsenate was further exacerbated. Contrary to expectations, studies on 24-h urinary speciation of sodium arsenate did not demonstrate any significant difference in arsenic biotransformation between Folbp2 -/- and Folbp2 +/+ mice. To better understand the influence of folate pathway genes on arsenic embryotoxicity, the present investigation utilized transgenic mice with disrupted folate binding protein 1 (Folbp1) and reduced folate carrier (RFC) genes. Because complete inactivation of Folbp1 and RFC genes results in embryonic lethality, we used heterozygous animals. Overall, no RFC genotype-related differences in embryonic susceptibility to arsenic exposure were observed. Embryonic lethality and neural tube defect (NTD) frequency in Folbp1 mice was dose-dependent and differed from the RFC mice; however, no genotype-related differences were observed. The RFC heterozygotes tended to have higher plasma levels of S-adenosylhomocysteine (SAH) than did the wild-type controls, although this effect was not robust. It is concluded that genetic modifications at the Folbp1 and RFC loci confers no particular sensitivity to arsenic toxicity compared to wild-type controls, thus disproving the working hypothesis that decreased methylating capacity of the genetically modified mice would put them at increased risk for arsenic-induced reproductive toxicity

  18. Transgenic mice for a tamoxifen-induced, conditional expression of the Cre recombinase in osteoclasts.

    Directory of Open Access Journals (Sweden)

    Maria Arantzazu Sanchez-Fernandez

    Full Text Available BACKGROUND: Studies on osteoclasts, the bone resorbing cells, have remained limited due to the lack of transgenic mice allowing the conditional knockout of genes in osteoclasts at any time during development or adulthood. METHODOLOGY/PRINCIPAL FINDING: We report here on the generation of transgenic mice which specifically express a tamoxifen-inducible Cre recombinase in osteoclasts. These mice, generated on C57BL/6 and FVB background, express a fusion Cre recombinase-ERT2 protein whose expression is driven by the promoter of cathepsin K (CtsK, a gene highly expressed in osteoclasts. We tested the cellular specificity of Cre activity in CtsKCreERT2 strains by breeding with Rosa26LacZ reporter mice. PCR and histological analyses of the CtsKCreERT2LacZ positive adult mice and E17.5 embryos show that Cre activity is restricted largely to bone tissue. In vitro, primary osteoclasts derived from the bone marrow of CtsKCreERT2+/-LacZ+/- adult mice show a Cre-dependent β-galactosidase activity after tamoxifen stimulation. CONCLUSIONS/SIGNIFICANCE: We have generated transgenic lines that enable the tamoxifen-induced, conditional deletion of loxP-flanked genes in osteoclasts, thus circumventing embryonic and postnatal gene lethality and avoiding gene deletion in other cell types. Such CtsKCreERT2 mice provide a convenient tool to study in vivo the different facets of osteoclast function in bone physiology during different developmental stages and adulthood of mice.

  19. Increased amphetamine-induced locomotor activity, sensitization, and accumbal dopamine release in M5 muscarinic receptor knockout mice

    DEFF Research Database (Denmark)

    Schmidt, Lene S; Miller, Anthony D; Lester, Deranda B

    2010-01-01

    showed that M(5) receptor knockout (M (5) (-/-) ) mice are less sensitive to the reinforcing properties of addictive drugs. MATERIALS AND METHODS: Here, we investigate the role of M(5) receptors in the effects of amphetamine and cocaine on locomotor activity, locomotor sensitization, and dopamine release......-induced hyperactivity and dopamine release as well as amphetamine sensitization are enhanced in mice lacking the M(5) receptor. These results support the concept that the M(5) receptor modulates effects of addictive drugs....

  20. Analgesic, anti-inflammatory and anti-pyretic activities of aqueous ethanolic extract of Tamarix aphylla L. (Saltcedar) in mice.

    Science.gov (United States)

    Qadir, Muhammad Imran; Abbas, Khizar; Hamayun, Rahma; Ali, Muhammad

    2014-11-01

    The objective of the study was to investigate the analgesic, anti-inflammatory and anti-pyretic activity of aqueous ethanolic extracts of Tamarix aphylla. The powdered plant was extracted by the method of cold maceration using aqueous ethanol (70:30) as solvents. Analgesic activity was assessed by Eddy's hot plate method, formalin-induced paw licking and acetic acid-induced writhing in mice. Anti-inflammatory activity was evaluated by carageenan-induced mice paw edema. The anti-pyretic activity was determined by yeast-induced pyrexia in mice. The aqueous ethanolic extract of Tamarix aphylla showed 42% inhibition (pTamarix aphylla exhibit analgesic and antipyretic activity but lacks anti-inflammatory activity.

  1. Differential gene expression in the murine gastric fundus lacking interstitial cells of Cajal

    Directory of Open Access Journals (Sweden)

    Ward Sean M

    2003-06-01

    Full Text Available Abstract Background The muscle layers of murine gastric fundus have no interstitial cells of Cajal at the level of the myenteric plexus and only possess intramuscular interstitial cells and this tissue does not generate electric slow waves. The absence of intramuscular interstitial cells in W/WV mutants provides a unique opportunity to study the molecular changes that are associated with the loss of these intercalating cells. Method The gene expression profile of the gastric fundus of wild type and W/WV mice was assayed by murine microarray analysis displaying a total of 8734 elements. Queried genes from the microarray analysis were confirmed by semi-quantitative reverse transcription-polymerase chain reaction. Results Twenty-one genes were differentially expressed in wild type and W/WV mice. Eleven transcripts had 2.0–2.5 fold higher mRNA expression in W/WV gastric fundus when compared to wild type tissues. Ten transcripts had 2.1–3.9 fold lower expression in W/WV mutants in comparison with wild type animals. None of these genes have ever been implicated in any bowel motility function. Conclusions These data provides evidence that several important genes have significantly changed in the murine fundus of W/WV mutants that lack intramuscular interstitial cells of Cajal and have reduced enteric motor neurotransmission.

  2. T-cells contribute to hypertension but not to renal injury in mice with subtotal nephrectomy

    NARCIS (Netherlands)

    Oosterhuis, Nynke R.; Papazova, Diana A.; Gremmels, Hendrik; Joles, Jaap A.; Verhaar, Marianne C.

    2017-01-01

    Background: The pathological condition of chronic kidney disease may not be adequately recapitulated in immunocompromised mice due to the lack of T-cells, which are important for the development of hypertension and renal injury. We studied the role of the immune system in relation to salt-sensitive

  3. Proportionate Dwarfism in Mice Lacking Heterochromatin Protein 1 Binding Protein 3 (HP1BP3) Is Associated With Alterations in the Endocrine IGF-1 Pathway.

    Science.gov (United States)

    Garfinkel, Benjamin P; Arad, Shiri; Le, Phuong T; Bustin, Michael; Rosen, Clifford J; Gabet, Yankel; Orly, Joseph

    2015-12-01

    Heterochromatin protein 1 binding protein 3 (HP1BP3) is a recently described histone H1-related protein with roles in chromatin structure and transcriptional regulation. To explore the potential physiological role of HP1BP3, we have previously described an Hp1bp3(-/-) mouse model with reduced postnatal viability and growth. We now find that these mice are proportionate dwarfs, with reduction in body weight, body length, and organ weight. In addition to their small size, microcomputed tomography analysis showed that Hp1bp3(-/-) mice present a dramatic impairment of their bone development and structure. By 3 weeks of age, mice of both sexes have severely impaired cortical and trabecular bone, and these defects persist into adulthood and beyond. Primary cultures of both osteoblasts and osteoclasts from Hp1bp3(-/-) bone marrow and splenocytes, respectively, showed normal differentiation and function, strongly suggesting that the impaired bone accrual is due to noncell autonomous systemic cues in vivo. One major endocrine pathway regulating both body growth and bone acquisition is the IGF regulatory system, composed of IGF-1, the IGF receptors, and the IGF-binding proteins (IGFBPs). At 3 weeks of age, Hp1bp3(-/-) mice exhibited a 60% reduction in circulating IGF-1 and a 4-fold increase in the levels of IGFBP-1 and IGFBP-2. These alterations were reflected in similar changes in the hepatic transcripts of the Igf1, Igfbp1, and Igfbp2 genes. Collectively, these results suggest that HP1BP3 plays a key role in normal growth and bone development by regulating transcription of endocrine IGF-1 components.

  4. Mice with Pulmonary Fibrosis Driven by Telomere Dysfunction

    Directory of Open Access Journals (Sweden)

    Juan M. Povedano

    2015-07-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a degenerative disease of the lungs with an average survival post-diagnosis of 2–3 years. New therapeutic targets and treatments are necessary. Mutations in components of the telomere-maintenance enzyme telomerase or in proteins important for telomere protection are found in both familial and sporadic IPF cases. However, the lack of mouse models that faithfully recapitulate the human disease has hampered new advances. Here, we generate two independent mouse models that develop IPF owing to either critically short telomeres (telomerase-deficient mice or severe telomere dysfunction in the absence of telomere shortening (mice with Trf1 deletion in type II alveolar cells. We show that both mouse models develop pulmonary fibrosis through induction of telomere damage, thus providing proof of principle of the causal role of DNA damage stemming from dysfunctional telomeres in IPF development and identifying telomeres as promising targets for new treatments.

  5. Project Management Web Tools at the MICE experiment

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Project management tools like Trac are commonly used within the open-source community to coordinate projects. The Muon Ionization Cooling Experiment (MICE) uses the project management web application Redmine to host mice.rl.ac.uk. Many groups within the experiment have a Redmine project: analysis, computing and software (including offline, online, controls and monitoring, and database subgroups), executive board, and operations. All of these groups use the website to communicate, track effort, develop schedules, and maintain documentation. The issue tracker is a rich tool that is used to identify tasks and monitor progress within groups on timescales ranging from immediate and unexpected problems to milestones that cover the life of the experiment. It allows the prioritization of tasks according to time-sensitivity, while providing a searchable record of work that has been done. This record of work can be used to measure both individual and overall group activity, identify areas lacking sufficient personne...

  6. Operant learning and differential-reinforcement-of-low-rate 36-s responding in 5-HT1A and 5-HT1B receptor knockout mice.

    NARCIS (Netherlands)

    Pattij, T.; Broersen, L.M.; Linde, J. van der; Groenink, L.; Gugten, J. van der; Maes, R.A.A.; Olivier, B.

    2003-01-01

    Previous studies with mice lacking 5-HT(1A) (1AKO) and 5-HT(1B) (1BKO) receptors in hippocampus-dependent learning and memory paradigms, suggest that these receptors play an important role in learning and memory, although their precise role is unclear. In the present study, 1AKO and 1BKO mice were

  7. Deficient plasticity in the primary visual cortex of alpha-calcium/calmodulin-dependent protein kinase II mutant mice.

    Science.gov (United States)

    Gordon, J A; Cioffi, D; Silva, A J; Stryker, M P

    1996-09-01

    The recent characterization of plasticity in the mouse visual cortex permits the use of mutant mice to investigate the cellular mechanisms underlying activity-dependent development. As calcium-dependent signaling pathways have been implicated in neuronal plasticity, we examined visual cortical plasticity in mice lacking the alpha-isoform of calcium/calmodulin-dependent protein kinase II (alpha CaMKII). In wild-type mice, brief occlusion of vision in one eye during a critical period reduces responses in the visual cortex. In half of the alpha CaMKII-deficient mice, visual cortical responses developed normally, but visual cortical plasticity was greatly diminished. After intensive training, spatial learning in the Morris water maze was severely impaired in a similar fraction of mutant animals. These data indicate that loss of alpha CaMKII results in a severe but variable defect in neuronal plasticity.

  8. Natural killer activity and suppressor cells in irradiated mice repopulated with a mixture of cells from normal and 89Sr-treated donors

    International Nuclear Information System (INIS)

    Levy, E.M.; Kumar, V.; Bennett, M.

    1981-01-01

    Mice that have been injected with 89 Sr have fairly normal B and T cell function, but are abnormal in that they lack natural killer (NK) activity and other functions that require an intact bone marrow. These mice also have an increased potential for suppressor cell activity. We had previously shown that spleen cells from 89 Sr-treated mice could transfer low NK activity and increased suppressor cell function to lethally irradiated syngeneic recipients. To investigate the mechanisms involved in perpetuating these defects, groups of normal spleen or bone marrow cells. Recipients were assayed for their NK activity and suppressor cell function 5 to 14 wk later. it was found that the addition of normal cells in the donor inoculum resulted in normal NK activity. This indicates that low NK activity in 89 Sr-treated mice was not due to the presence of a suppressor cell that prevented NK cell generation. It was additionally found that low NK activity in recipient mice could be boosted by interferon inducers. This would indicate that NK activity in the recipients was not due to a lack of interferon-sensitive pre-NK cells. Suppressor cell function in recipient mice depended on the type and number of normal cells in the donor inoculum. Bone marrow cells were very efficient in overcoming the tendency to produce suppressor cells. It took approximately 20 times more normal spleen cells to produce the same results. The implications of these findings are discussed

  9. Dopamine D3 receptor knockout mice exhibit abnormal nociception in a sex-different manner.

    Science.gov (United States)

    Liu, Peng; Xing, Bo; Chu, Zheng; Liu, Fei; Lei, Gang; Zhu, Li; Gao, Ya; Chen, Teng; Dang, Yong-Hui

    2017-07-01

    Pain is a complex and subjective experience. Previous studies have shown that mice lacking the dopamine D3 receptor (D3RKO) exhibit hypoalgesia, indicating a role of the D3 receptor in modulation of nociception. Given that there are sex differences in pain perception, there may be differences in responses to nociceptive stimuli between male and female D3RKO mice. In the current study, we examined the role of the D3 receptor in modulating nociception in male and female D3RKO mice. Acute thermal pain was modeled by hot-plate test. This test was performed at different temperatures including 52°C, 55°C, and 58°C. The von Frey hair test was applied to evaluate mechanical pain. And persistent pain produced by peripheral tissue injury and inflammation was modeled by formalin test. In the hot-plate test, compared with wild-type (WT) mice, D3RKO mice generally exhibited longer latencies at each of the three temperatures. Specially, male D3RKO mice showed hypoalgesia compared with male WT mice when the temperature was 55°C, while for the female mice, there was a statistical difference between genotypes when the test condition was 52°C. In the von Frey hair test, both male and female D3RKO mice exhibited hypoalgesia. In the formalin test, the male D3RKO mice displayed a similar nociceptive behavior as their sex-matched WT littermates, whereas significantly depressed late-phase formalin-induced nociceptive behaviors were observed in the female mutants. These findings indicated that the D3 receptor affects nociceptive behaviors in a sex-specific manner and that its absence induces more analgesic behavior in the female knockout mice. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Self-recognition specificity expressed by T cells from nude mice. Absence of detectable Ia-restricted T cells in nude mice that do exhibit self-K/D-restricted T cell responses

    International Nuclear Information System (INIS)

    Kruisbeek, A.M.; Davis, M.L.; Matis, L.A.; Longo, D.L.

    1984-01-01

    The presence in athymic nude mice of precursor T cells with self-recognition specificity for either H-2 K/D or H-2 I region determinants was investigated. Chimeras were constructed of lethally irradiated parental mice receiving a mixture of F1 nude mouse (6-8 wk old) spleen and bone marrow cells. The donor inoculum was deliberately not subjected to any T cell depletion procedure, so that any potential major histocompatibility complex-committed precursor T cells were allowed to differentiate and expand in the normal parental recipients. 3 mo after reconstitution, the chimeras were immunized with several protein antigens in complete Freund's adjuvant in the footpads and their purified draining lymph node T cells tested 10 d later for ability to recognize antigen on antigen-presenting cells of either parental haplotype. Also, their spleen and lymph node cells were tested for ability to generate a cytotoxic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified stimulator cells of either parental haplotype. It was demonstrated that T cell proliferative responses of these F1(nude)----parent chimeras were restricted solely to recognizing parental host I region determinants as self and expressed the Ir gene phenotype of the host. In contrast, CTL responses could be generated (in the presence of interleukin 2) to TNP-modified stimulator cells of either parental haplotype. Thus these results indicate that nude mice which do have CTL with self-specificity for K/D region determinants lack proliferating T cells with self-specificity for I region determinants. These results provide evidence for the concepts that development of the I region-restricted T cell repertoire is strictly an intrathymically determined event and that young nude mice lack the unique thymic elements responsible for education of I region-restricted T cells

  11. Effect of thumus cell injections on germinal center formation in lymphoid tissues of nude (thymusless) mice

    International Nuclear Information System (INIS)

    Jacobson, E.B.; Caporale, L.H.; Thorbecke, G.J.

    1974-01-01

    Nude mice, partially backcrossed to Balb/c or DBA/2, were injected iv with 5 x 10 7 thymus cells from the respective inbred strain. The response of these mice to immunization with Brucella abortus antigen was studied, with respect to both antibody production and the formation of germinal centers in their lymphoid tissues. The results were compared to those obtained with nude mice to which no thymus cells were given, as well as to Balb/c, DBA/2, or +/question litter mate controls. Nude mice formed less 19S as well as 7S antibody than did litter mate controls and completely lacked germinal centers in lymph nodes and gut-associated lymphoid tissue. Those nude mice which had been injected with thymus cells made a much better secondary response, both for 19S and for 7S antibody, and had active germinal centers in their lymph nodes as early as 3 wk after thymus cell injection. Intestinal lymphoid tissue in nude mice showed only slight reconstitution of germinal center activity several months after thymus cell injection and none at earlier times. Irradiated (3000 R) thymus cells appeared as effective as normal cells in facilitating germinal center appearance and 7S antibody production in the nude mice

  12. Deletion of ultraconserved elements yields viable mice

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    Ahituv, Nadav; Zhu, Yiwen; Visel, Axel; Holt, Amy; Afzal, Veena; Pennacchio, Len A.; Rubin, Edward M.

    2007-07-15

    Ultraconserved elements have been suggested to retainextended perfect sequence identity between the human, mouse, and ratgenomes due to essential functional properties. To investigate thenecessities of these elements in vivo, we removed four non-codingultraconserved elements (ranging in length from 222 to 731 base pairs)from the mouse genome. To maximize the likelihood of observing aphenotype, we chose to delete elements that function as enhancers in amouse transgenic assay and that are near genes that exhibit markedphenotypes both when completely inactivated in the mouse as well as whentheir expression is altered due to other genomic modifications.Remarkably, all four resulting lines of mice lacking these ultraconservedelements were viable and fertile, and failed to reveal any criticalabnormalities when assayed for a variety of phenotypes including growth,longevity, pathology and metabolism. In addition more targeted screens,informed by the abnormalities observed in mice where genes in proximityto the investigated elements had been altered, also failed to revealnotable abnormalities. These results, while not inclusive of all thepossible phenotypic impact of the deleted sequences, indicate thatextreme sequence constraint does not necessarily reflect crucialfunctions required for viability.

  13. Red wine polyphenol compounds favor neovascularisation through estrogen receptor α-independent mechanism in mice.

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    Matthieu Chalopin

    Full Text Available Red wine polyphenol compounds (RWPC exert paradoxical effects depending on the dose on post-ischemic neovascularisation. Low dose RWPC (0.2 mg/kg/day is pro-angiogenic, whereas high dose (20 mg/kg/day is anti-angiogenic. We recently reported that the endothelial effect of RWPC is mediated through the activation of a redox-sensitive pathway, mitochondrial biogenesis and the activation of α isoform of the estrogen receptor (ERα. Here, we investigated the implication of ERα on angiogenic properties of RWPC. Using ovariectomized mice lacking ERα treated with high dose of RWPC after hindlimb ischemia, we examined blood flow reperfusion, vascular density, nitric oxide (NO production, expression and activation of proteins involved in angiogenic process and muscle energy sensing network. As expected, high dose of RWPC treatment reduced both blood flow and vascular density in muscles of mice expressing ERα. These effects were associated with reduced NO production resulting from diminished activity of eNOS. In the absence of RWPC, ERα deficient mice showed a reduced neo-vascularisation associated with a decreased NO production. Surprisingly in mice lacking ERα, high dose of RWPC increased blood flow and capillary density in conjunction with increased NO pathway and production as well as VEGF expression. Of particular interest is the activation of Sirt-1, AMPKα and PGC-1α/β axis in ischemic hindlimb from both strains. Altogether, the results highlight a pro-angiogenic property of RWPC via an ERα-independent mechanism that is associated with an up-regulation of energy sensing network. This study brings a corner stone of a novel pathway for RWPC to correct cardiovascular diseases associated with failed neovascularisation.

  14. Male-like sexual behavior of female mouse lacking fucose mutarotase

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    Lim Dae-sik

    2010-07-01

    Full Text Available Abstract Background Mutarotases are recently characterized family of enzymes that are involved in the anomeric conversions of monosaccharides. The mammalian fucose mutarotase (FucM was reported in cultured cells to facilitate fucose utilization and incorporation into protein by glycosylation. However, the role of this enzyme in animal has not been elucidated. Results We generated a mutant mouse specifically lacking the fucose mutarotase (FucM gene. The FucM knockout mice displayed an abnormal sexual receptivity with a drastic reduction in lordosis score, although the animals were fertile due to a rare and forced intromission by a typical male. We examined the anteroventral periventricular nucleus (AVPv of the preoptic region in brain and found that the mutant females showed a reduction in tyrosine hydoxylase positive neurons compared to that of a normal female. Furthermore, the mutant females exhibited a masculine behavior, such as mounting to a normal female partner as well as showing a preference to female urine. We found a reduction of fucosylated serum alpha-fetoprotein (AFP in a mutant embryo relative to that of a wild-type embryo. Conclusions The observation that FucM-/- female mouse exhibits a phenotypic similarity to a wild-type male in terms of its sexual behavior appears to be due to the neurodevelopmental changes in preoptic area of mutant brain resembling a wild-type male. Since the previous studies indicate that AFP plays a role in titrating estradiol that are required to consolidate sexual preference of female mice, we speculate that the reduced level of AFP in FucM-/- mouse, presumably resulting from the reduced fucosylation, is responsible for the male-like sexual behavior observed in the FucM knock-out mouse.

  15. Macrophage Depletion Ameliorates Peripheral Neuropathy in Aging Mice.

    Science.gov (United States)

    Yuan, Xidi; Klein, Dennis; Kerscher, Susanne; West, Brian L; Weis, Joachim; Katona, Istvan; Martini, Rudolf

    2018-05-09

    Aging is known as a major risk factor for the structure and function of the nervous system. There is urgent need to overcome such deleterious effects of age-related neurodegeneration. Here we show that peripheral nerves of 24-month-old aging C57BL/6 mice of either sex show similar pathological alterations as nerves from aging human individuals, whereas 12-month-old adult mice lack such alterations. Specifically, nerve fibers showed demyelination, remyelination and axonal lesion. Moreover, in the aging mice, neuromuscular junctions showed features typical for dying-back neuropathies, as revealed by a decline of presynaptic markers, associated with α-bungarotoxin-positive postsynapses. In line with these observations were reduced muscle strengths. These alterations were accompanied by elevated numbers of endoneurial macrophages, partially comprising the features of phagocytosing macrophages. Comparable profiles of macrophages could be identified in peripheral nerve biopsies of aging persons. To determine the pathological impact of macrophages in aging mice, we selectively targeted the cells by applying an orally administered CSF-1R specific kinase (c-FMS) inhibitor. The 6-month-lasting treatment started before development of degenerative changes at 18 months and reduced macrophage numbers in mice by ∼70%, without side effects. Strikingly, nerve structure was ameliorated and muscle strength preserved. We show, for the first time, that age-related degenerative changes in peripheral nerves are driven by macrophages. These findings may pave the way for treating degeneration in the aging peripheral nervous system by targeting macrophages, leading to reduced weakness, improved mobility, and eventually increased quality of life in the elderly. SIGNIFICANCE STATEMENT Aging is a major risk factor for the structure and function of the nervous system. Here we show that peripheral nerves of 24-month-old aging mice show similar degenerative alterations as nerves from aging

  16. Oxidized CaMKII causes cardiac sinus node dysfunction in mice

    Science.gov (United States)

    Swaminathan, Paari Dominic; Purohit, Anil; Soni, Siddarth; Voigt, Niels; Singh, Madhu V.; Glukhov, Alexey V.; Gao, Zhan; He, B. Julie; Luczak, Elizabeth D.; Joiner, Mei-ling A.; Kutschke, William; Yang, Jinying; Donahue, J. Kevin; Weiss, Robert M.; Grumbach, Isabella M.; Ogawa, Masahiro; Chen, Peng-Sheng; Efimov, Igor; Dobrev, Dobromir; Mohler, Peter J.; Hund, Thomas J.; Anderson, Mark E.

    2011-01-01

    Sinus node dysfunction (SND) is a major public health problem that is associated with sudden cardiac death and requires surgical implantation of artificial pacemakers. However, little is known about the molecular and cellular mechanisms that cause SND. Most SND occurs in the setting of heart failure and hypertension, conditions that are marked by elevated circulating angiotensin II (Ang II) and increased oxidant stress. Here, we show that oxidized calmodulin kinase II (ox-CaMKII) is a biomarker for SND in patients and dogs and a disease determinant in mice. In wild-type mice, Ang II infusion caused sinoatrial nodal (SAN) cell oxidation by activating NADPH oxidase, leading to increased ox-CaMKII, SAN cell apoptosis, and SND. p47–/– mice lacking functional NADPH oxidase and mice with myocardial or SAN-targeted CaMKII inhibition were highly resistant to SAN apoptosis and SND, suggesting that ox-CaMKII–triggered SAN cell death contributed to SND. We developed a computational model of the sinoatrial node that showed that a loss of SAN cells below a critical threshold caused SND by preventing normal impulse formation and propagation. These data provide novel molecular and mechanistic information to understand SND and suggest that targeted CaMKII inhibition may be useful for preventing SND in high-risk patients. PMID:21785215

  17. Hippocampal network oscillations in APP/APLP2-deficient mice.

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    Xiaomin Zhang

    Full Text Available The physiological function of amyloid precursor protein (APP and its two homologues APP-like protein 1 (APLP1 and 2 (APLP2 is largely unknown. Previous work suggests that lack of APP or APLP2 impairs synaptic plasticity and spatial learning. There is, however, almost no data on the role of APP or APLP at the network level which forms a critical interface between cellular functions and behavior. We have therefore investigated memory-related synaptic and network functions in hippocampal slices from three lines of transgenic mice: APPsα-KI (mice expressing extracellular fragment of APP, corresponding to the secreted APPsα ectodomain, APLP2-KO, and combined APPsα-KI/APLP2-KO (APPsα-DM for "double mutants". We analyzed two prominent patterns of network activity, gamma oscillations and sharp-wave ripple complexes (SPW-R. Both patterns were generally preserved in all strains. We find, however, a significantly reduced frequency of gamma oscillations in CA3 of APLP2-KO mice in comparison to APPsα-KI and WT mice. Network activity, basic synaptic transmission and short-term plasticity were unaltered in the combined mutants (APPsα-DM which showed, however, reduced long-term potentiation (LTP. Together, our data indicate that APLP2 and the intracellular domain of APP are not essential for coherent activity patterns in the hippocampus, but have subtle effects on synaptic plasticity and fine-tuning of network oscillations.

  18. CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity.

    Science.gov (United States)

    Cappel, David A; Lantier, Louise; Palmisano, Brian T; Wasserman, David H; Stafford, John M

    2015-01-01

    Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD) feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity.

  19. CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity.

    Directory of Open Access Journals (Sweden)

    David A Cappel

    Full Text Available Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD. Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α. These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity.

  20. Absence of ERK5/MAPK7 delays tumorigenesis in Atm-/- mice.

    Science.gov (United States)

    Granados-Jaén, Alba; Angulo-Ibáñez, Maria; Rovira-Clavé, Xavier; Gamez, Celina Paola Vasquez; Soriano, Francesc X; Reina, Manuel; Espel, Enric

    2016-11-15

    Ataxia-telangiectasia mutated (ATM) is a cell cycle checkpoint kinase that upon activation by DNA damage leads to cell cycle arrest and DNA repair or apoptosis. The absence of Atm or the occurrence of loss-of-function mutations in Atm predisposes to tumorigenesis. MAPK7 has been implicated in numerous types of cancer with pro-survival and pro-growth roles in tumor cells, but its functional relation with tumor suppressors is not clear. In this study, we show that absence of MAPK7 delays death due to spontaneous tumor development in Atm-/- mice. Compared with Atm-/- thymocytes, Mapk7-/-Atm-/- thymocytes exhibited an improved response to DNA damage (increased phosphorylation of H2AX) and a restored apoptotic response after treatment of mice with ionizing radiation. These findings define an antagonistic function of ATM and MAPK7 in the thymocyte response to DNA damage, and suggest that the lack of MAPK7 inhibits thymic lymphoma growth in Atm-/- mice by partially restoring the DNA damage response in thymocytes.

  1. Toxicity bioassay in mice exposed to low dose-rate radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joog Sun; Gong, Eun Ji; Heo, Kyu; Yang, Kwang Mo [Research Center, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of)

    2013-04-15

    The systemic effect of radiation increases in proportion to the dose amount and rate. The association between accumulated radiation dose and adverse effects, which is derived according to continuous low dose-rate radiation exposure, is not clearly elucidated. Our previous study showed that low dose-rate radiation exposure did not cause adverse effects in BALB/c mice at dose levels of ≤2 Gy, but the testis weight decreased at a dose of 2 Gy. In this study, we studied the effects of irradiation at the low dose rate (3.49 mGy/h) in the testes of C57BL/6 mice. Mice exposed to a total dose of 0.02, 0.2, and 2 Gy were found to be healthy and did not show any significant changes in body weight and peripheral blood components. However, mice irradiated with a dose of 2 Gy had significantly decreased testis weight. Further, histological studies and sperm evaluation also demonstrated changes consistent with the findings of decreased testis weight. In fertile patients found to have arrest of sperm maturation, the seminiferous tubules lack the DNMT1 and HDAC1 protein. The decrease of DNMT1 and HDAC1 in irradiated testis may be the part of the mechanism via which low dose-rate irradiation results in teticular injury. In conclusion, despite a low dose-rate radiation, our study found that when mice testis were irradiated with 2 Gy at 3.49 mGy/h dose rate, there was significant testicular and sperm damage with decreased DNMT1 and HDAC1 expression.

  2. Joint pathology and behavioral performance in autoimmune MRL-lpr Mice.

    Science.gov (United States)

    Sakić, B; Szechtman, H; Stead, R H; Denburg, J A

    1996-09-01

    Young autoimmune MRL-lpr mice perform more poorly than age-matched controls in tests of exploration, spatial learning, and emotional reactivity. Impaired behavioral performance coincides temporally with hyperproduction of autoantibodies, infiltration of lymphoid cells into the brain, and mild arthritic-like changes in hind paws. Although CNS mechanisms have been suggested to mediate behavioral deficits, it was not clear whether mild joint pathology significantly affected behavioral performance. Previously we observed that 11-week-old MRL-lpr mice showed a trend for disturbed performance when crossing a narrow beam. The first aim of the present study was to test the significance of this trend by increasing the sample size and, second, to examine the possibility that arthritis-like changes interfere with performance in brief locomotor tasks. For the purpose of the second goal, 18-week-old mice that differ widely in severity of joint disease were selectively taken from the population and tested in beam walking and swimming tasks. It was expected that the severity of joint inflammation would be positively correlated with the degree of locomotor impairment. The larger sample size revealed that young MRL-lpr mice perform significantly more poorly than controls on the beam-walking test, as evidenced by more foot slips and longer traversing time. However, significant correlation between joint pathology scores and measures of locomotion could not be detected. The lack of such relationship suggests that mild joint pathology does not significantly contribute to impaired performance in young, autoimmune MRL-lpr mice tested in short behavioral tasks.

  3. Generation and analysis of knock-in mice carrying pseudohypoaldosteronism type II-causing mutations in the cullin 3 gene.

    Science.gov (United States)

    Araki, Yuya; Rai, Tatemitsu; Sohara, Eisei; Mori, Takayasu; Inoue, Yuichi; Isobe, Kiyoshi; Kikuchi, Eriko; Ohta, Akihito; Sasaki, Sei; Uchida, Shinichi

    2015-10-21

    Pseudohypoaldosteronism type II (PHAII) is a hereditary hypertensive disease caused by mutations in four different genes: with-no-lysine kinases (WNK) 1 and 4, Kelch-like family member 3 (KLHL3), and cullin 3 (Cul3). Cul3 and KLHL3 form an E3 ligase complex that ubiquitinates and reduces the expression level of WNK4. PHAII-causing mutations in WNK4 and KLHL3 impair WNK4 ubiquitination. However, the molecular pathogenesis of PHAII caused by Cul3 mutations is unclear. In cultured cells and human leukocytes, PHAII-causing Cul3 mutations result in the skipping of exon 9, producing mutant Cul3 protein lacking 57 amino acids. However, whether this phenomenon occurs in the kidneys and is responsible for the pathogenesis of PHAII in vivo is unknown. We generated knock-in mice carrying a mutation in the C-terminus of intron 8 of Cul3, c.1207-1G>A, which corresponds to a PHAII-causing mutation in the human Cul3 gene. Heterozygous Cul3(G(-1)A/+) knock-in mice did not exhibit PHAII phenotypes, and the skipping of exon 9 was not evident in their kidneys. However, the level of Cul3 mRNA expression in the kidneys of heterozygous knock-in mice was approximately half that of wild-type mice. Furthermore, homozygous knock-in mice were nonviable. It suggested that the mutant allele behaved like a knockout allele and did not produce Cul3 mRNA lacking exon 9. A reduction in Cul3 expression alone was not sufficient to develop PHAII in the knock-in mice. Our findings highlighted the pathogenic role of mutant Cul3 protein and provided insight to explain why PHAII-causing mutations in Cul3 cause kidney-predominant PHAII phenotypes. © 2015. Published by The Company of Biologists Ltd.

  4. Automated classification of self-grooming in mice using open-source software.

    Science.gov (United States)

    van den Boom, Bastijn J G; Pavlidi, Pavlina; Wolf, Casper J H; Mooij, Adriana H; Willuhn, Ingo

    2017-09-01

    Manual analysis of behavior is labor intensive and subject to inter-rater variability. Although considerable progress in automation of analysis has been made, complex behavior such as grooming still lacks satisfactory automated quantification. We trained a freely available, automated classifier, Janelia Automatic Animal Behavior Annotator (JAABA), to quantify self-grooming duration and number of bouts based on video recordings of SAPAP3 knockout mice (a mouse line that self-grooms excessively) and wild-type animals. We compared the JAABA classifier with human expert observers to test its ability to measure self-grooming in three scenarios: mice in an open field, mice on an elevated plus-maze, and tethered mice in an open field. In each scenario, the classifier identified both grooming and non-grooming with great accuracy and correlated highly with results obtained by human observers. Consistently, the JAABA classifier confirmed previous reports of excessive grooming in SAPAP3 knockout mice. Thus far, manual analysis was regarded as the only valid quantification method for self-grooming. We demonstrate that the JAABA classifier is a valid and reliable scoring tool, more cost-efficient than manual scoring, easy to use, requires minimal effort, provides high throughput, and prevents inter-rater variability. We introduce the JAABA classifier as an efficient analysis tool for the assessment of rodent self-grooming with expert quality. In our "how-to" instructions, we provide all information necessary to implement behavioral classification with JAABA. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Absence of the inflammasome adaptor ASC reduces hypoxia-induced pulmonary hypertension in mice.

    Science.gov (United States)

    Cero, Fadila Telarevic; Hillestad, Vigdis; Sjaastad, Ivar; Yndestad, Arne; Aukrust, Pål; Ranheim, Trine; Lunde, Ida Gjervold; Olsen, Maria Belland; Lien, Egil; Zhang, Lili; Haugstad, Solveig Bjærum; Løberg, Else Marit; Christensen, Geir; Larsen, Karl-Otto; Skjønsberg, Ole Henning

    2015-08-15

    Pulmonary hypertension is a serious condition that can lead to premature death. The mechanisms involved are incompletely understood although a role for the immune system has been suggested. Inflammasomes are part of the innate immune system and consist of the effector caspase-1 and a receptor, where nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) is the best characterized and interacts with the adaptor protein apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC). To investigate whether ASC and NLRP3 inflammasome components are involved in hypoxia-induced pulmonary hypertension, we utilized mice deficient in ASC and NLRP3. Active caspase-1, IL-18, and IL-1β, which are regulated by inflammasomes, were measured in lung homogenates in wild-type (WT), ASC(-/-), and NLRP3(-/-) mice, and phenotypical changes related to pulmonary hypertension and right ventricular remodeling were characterized after hypoxic exposure. Right ventricular systolic pressure (RVSP) of ASC(-/-) mice was significantly lower than in WT exposed to hypoxia (40.8 ± 1.5 mmHg vs. 55.8 ± 2.4 mmHg, P right ventricular remodeling. RVSP of NLRP3(-/-) mice exposed to hypoxia was not significantly altered compared with WT hypoxia. Whereas hypoxia increased protein levels of caspase-1, IL-18, and IL-1β in WT and NLRP3(-/-) mice, this response was absent in ASC(-/-) mice. Moreover, ASC(-/-) mice displayed reduced muscularization and collagen deposition around arteries. In conclusion, hypoxia-induced elevated right ventricular pressure and remodeling were attenuated in mice lacking the inflammasome adaptor protein ASC, suggesting that inflammasomes play an important role in the pathogenesis of pulmonary hypertension. Copyright © 2015 the American Physiological Society.

  6. Targeted deletion of Nrf2 reduces urethane-induced lung tumor development in mice.

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    Alison K Bauer

    Full Text Available Nrf2 is a key transcription factor that regulates cellular redox and defense responses. However, permanent Nrf2 activation in human lung carcinomas promotes pulmonary malignancy and chemoresistance. We tested the hypothesis that Nrf2 has cell survival properties and lack of Nrf2 suppresses chemically-induced pulmonary neoplasia by treating Nrf2(+/+ and Nrf2(-/- mice with urethane. Airway inflammation and injury were assessed by bronchoalveolar lavage analyses and histopathology, and lung tumors were analyzed by gross and histologic analysis. We used transcriptomics to assess Nrf2-dependent changes in pulmonary gene transcripts at multiple stages of neoplasia. Lung hyperpermeability, cell death and apoptosis, and inflammatory cell infiltration were significantly higher in Nrf2(-/- mice compared to Nrf2(+/+ mice 9 and 11 wk after urethane. Significantly fewer lung adenomas were found in Nrf2(-/- mice than in Nrf2(+/+ mice at 12 and 22 wk. Nrf2 modulated expression of genes involved cell-cell signaling, glutathione metabolism and oxidative stress response, and immune responses during early stage neoplasia. In lung tumors, Nrf2-altered genes had roles in transcriptional regulation of cell cycle and proliferation, carcinogenesis, organismal injury and abnormalities, xenobiotic metabolism, and cell-cell signaling genes. Collectively, Nrf2 deficiency decreased susceptibility to urethane-induced lung tumorigenesis in mice. Cell survival properties of Nrf2 were supported, at least in part, by reduced early death of initiated cells and heightened advantage for tumor cell expansion in Nrf2(+/+ mice relative to Nrf2(-/- mice. Our results were consistent with the concept that Nrf2 over-activation is an adaptive response of cancer conferring resistance to anti-cancer drugs and promoting malignancy.

  7. Successful adaptation to ketosis by mice with tissue-specific deficiency of ketone body oxidation.

    Science.gov (United States)

    Cotter, David G; Schugar, Rebecca C; Wentz, Anna E; d'Avignon, D André; Crawford, Peter A

    2013-02-15

    During states of low carbohydrate intake, mammalian ketone body metabolism transfers energy substrates originally derived from fatty acyl chains within the liver to extrahepatic organs. We previously demonstrated that the mitochondrial enzyme coenzyme A (CoA) transferase [succinyl-CoA:3-oxoacid CoA transferase (SCOT), encoded by nuclear Oxct1] is required for oxidation of ketone bodies and that germline SCOT-knockout (KO) mice die within 48 h of birth because of hyperketonemic hypoglycemia. Here, we use novel transgenic and tissue-specific SCOT-KO mice to demonstrate that ketone bodies do not serve an obligate energetic role within highly ketolytic tissues during the ketogenic neonatal period or during starvation in the adult. Although transgene-mediated restoration of myocardial CoA transferase in germline SCOT-KO mice is insufficient to prevent lethal hyperketonemic hypoglycemia in the neonatal period, mice lacking CoA transferase selectively within neurons, cardiomyocytes, or skeletal myocytes are all viable as neonates. Like germline SCOT-KO neonatal mice, neonatal mice with neuronal CoA transferase deficiency exhibit increased cerebral glycolysis and glucose oxidation, and, while these neonatal mice exhibit modest hyperketonemia, they do not develop hypoglycemia. As adults, tissue-specific SCOT-KO mice tolerate starvation, exhibiting only modestly increased hyperketonemia. Finally, metabolic analysis of adult germline Oxct1(+/-) mice demonstrates that global diminution of ketone body oxidation yields hyperketonemia, but hypoglycemia emerges only during a protracted state of low carbohydrate intake. Together, these data suggest that, at the tissue level, ketone bodies are not a required energy substrate in the newborn period or during starvation, but rather that integrated ketone body metabolism mediates adaptation to ketogenic nutrient states.

  8. Fucosylation Deficiency in Mice Leads to Colitis and Adenocarcinoma

    Science.gov (United States)

    Wang, Yiwei; Huang, Dan; Chen, Kai-Yuan; Cui, Min; Wang, Weihuan; Huang, Xiaoran; Awadellah, Amad; Li, Qing; Friedman, Ann; Xin, William W.; Di Martino, Luca; Cominelli, Fabio; Miron, Alex; Chan, Ricky; Fox, James; Xu, Yan; Shen, Xiling; Kalady, Mathew F.; Markowitz, Sanford; Maillard, Ivan; Lowe, John B.; Xin, Wei; Zhou, Lan

    2016-01-01

    Background & Aims De novo synthesis of GDP-fucose, a substrate for fucosylglycans, requires sequential reactions mediated by GDP-mannose 4,6-dehydratase (GMDS) and GDP-4-keto-6-deoxymannose 3,5-epimerase-4-reductase (FX or TSTA3). GMDS deletions and mutations are found in 6%–13% of colorectal cancers; these mostly affect ascending and transverse colon. We investigated whether lack of fucosylation consequent to loss of GDP-fucose synthesis contributes to colon carcinogenesis. Methods FX deficiency and GMDS deletion produce the same biochemical phenotype of GDP-fucose deficiency. We studied a mouse model of fucosylation deficiency (Fx–/– mice) and mice with the full-length Fx gene (controls). Mice were placed on standard chow or fucose-containing diet (equivalent to a control fucosylglycan phenotype). Colon tissues were collected and analyzed histologically or by ELISAs to measure cytokine levels; T cells were also collected and analyzed. Fecal samples were analyzed by 16s rRNA sequencing. Mucosal barrier function was measured by uptake of fluorescent dextran. We transplanted bone marrow cells from Fx–/– or control mice (Ly5.2) into irradiated 8-week old Fx–/– or control mice (Ly5.1). We performed immunohistochemical analyses for expression of Notch and the hes family bHLH transcription factor (HES1) in colon tissues from mice and a panel of 60 human colorectal cancer specimens (27 left-sided, 33 right-sided). Results Fx–/– mice developed colitis and serrated-like lesions. The intestinal pathology of Fx–/– mice was reversed by addition of fucose to the diet, which restored fucosylation via a salvage pathway. In the absence of fucosylation, dysplasia appeared and progressed to adenocarcinoma in up to 40% of mice, affecting mainly the right colon and cecum. Notch was not activated in Fx–/– mice fed standard chow, leading to decreased expression of its target Hes1. Fucosylation deficiency altered the composition of the fecal microbiota, reduced

  9. Orally administered nicotine induces urothelial hyperplasia in rats and mice

    International Nuclear Information System (INIS)

    Dodmane, Puttappa R.; Arnold, Lora L.; Pennington, Karen L.; Cohen, Samuel M.

    2014-01-01

    Highlights: • Rats and mice orally administered with nicotine tartrate for total of 4 weeks. • No treatment-related death or whole body toxicity observed in any of the groups. • Urothelium showed simple hyperplasia in treated rats and mice. • No significant change in BrdU labeling index or SEM classification of urothelium. - Abstract: Tobacco smoking is a major risk factor for multiple human cancers including urinary bladder carcinoma. Tobacco smoke is a complex mixture containing chemicals that are known carcinogens in humans and/or animals. Aromatic amines a major class of DNA-reactive carcinogens in cigarette smoke, are not present at sufficiently high levels to fully explain the incidence of bladder cancer in cigarette smokers. Other agents in tobacco smoke could be excreted in urine and enhance the carcinogenic process by increasing urothelial cell proliferation. Nicotine is one such major component, as it has been shown to induce cell proliferation in multiple cell types in vitro. However, in vivo evidence specifically for the urothelium is lacking. We previously showed that cigarette smoke induces increased urothelial cell proliferation in mice. In the present study, urothelial proliferative and cytotoxic effects were examined after nicotine treatment in mice and rats. Nicotine hydrogen tartrate was administered in drinking water to rats (52 ppm nicotine) and mice (514 ppm nicotine) for 4 weeks and urothelial changes were evaluated. Histopathologically, 7/10 rats and 4/10 mice showed simple hyperplasia following nicotine treatment compared to none in the controls. Rats had an increased mean BrdU labeling index compared to controls, although it was not statistically significantly elevated in either species. Scanning electron microscopic visualization of the urothelium did not reveal significant cytotoxicity. These findings suggest that oral nicotine administration induced urothelial hyperplasia (increased cell proliferation), possibly due to a

  10. 3D visualization and quantification of bone and teeth mineralization for the study of osteo/dentinogenesis in mice models

    Science.gov (United States)

    Marchadier, A.; Vidal, C.; Ordureau, S.; Lédée, R.; Léger, C.; Young, M.; Goldberg, M.

    2011-03-01

    Research on bone and teeth mineralization in animal models is critical for understanding human pathologies. Genetically modified mice represent highly valuable models for the study of osteo/dentinogenesis defects and osteoporosis. Current investigations on mice dental and skeletal phenotype use destructive and time consuming methods such as histology and scanning microscopy. Micro-CT imaging is quicker and provides high resolution qualitative phenotypic description. However reliable quantification of mineralization processes in mouse bone and teeth are still lacking. We have established novel CT imaging-based software for accurate qualitative and quantitative analysis of mouse mandibular bone and molars. Data were obtained from mandibles of mice lacking the Fibromodulin gene which is involved in mineralization processes. Mandibles were imaged with a micro-CT originally devoted to industrial applications (Viscom, X8060 NDT). 3D advanced visualization was performed using the VoxBox software (UsefulProgress) with ray casting algorithms. Comparison between control and defective mice mandibles was made by applying the same transfer function for each 3D data, thus allowing to detect shape, colour and density discrepencies. The 2D images of transverse slices of mandible and teeth were similar and even more accurate than those obtained with scanning electron microscopy. Image processing of the molars allowed the 3D reconstruction of the pulp chamber, providing a unique tool for the quantitative evaluation of dentinogenesis. This new method is highly powerful for the study of oro-facial mineralizations defects in mice models, complementary and even competitive to current histological and scanning microscopy appoaches.

  11. Chronic copper exposure causes spatial memory impairment, selective loss of hippocampal synaptic proteins, and activation of PKR/eIF2α pathway in mice.

    Science.gov (United States)

    Ma, Quan; Ying, Ming; Sui, Xiaojing; Zhang, Huimin; Huang, Haiyan; Yang, Linqing; Huang, Xinfeng; Zhuang, Zhixiong; Liu, Jianjun; Yang, Xifei

    2015-01-01

    Copper is an essential element for human growth and development; however, excessive intake of copper could contribute to neurotoxicity. Here we show that chronic exposure to copper in drinking water impaired spatial memory with simultaneous selective loss of hippocampal pre-synaptic protein synapsin 1, and post-synaptic density protein (PSD)-93/95 in mice. Copper exposure was shown to elevate the levels of nitrotyrosine and 8-hydroxydeoxyguanosine (8-OHdG) in hippocampus, two markers of oxidative stress. Concurrently, we also found that copper exposure activated double stranded RNA-dependent protein kinase (PKR) as evidenced by increased ratio of phosphorylated PKR at Thr451 and total PKR and increased the phosphorylation of its downstream signaling molecule eukaryotic initiation factor 2α (eIF2α) at Ser51 in hippocampus. Consistent with activation of PKR/eIF2α signaling pathway which was shown to mediate synaptic deficit and cognitive impairment, the levels of activating transcription factor 4 (ATF-4), a downstream signaling molecule of eIF2α and a repressor of CREB-mediated gene expression, were significantly increased, while the activity of cAMP response elements binding protein (CREB) was inactivated as suggested by decreased phosphorylation of CREB at Ser133 by copper exposure. In addition, the expression of the pro-apoptotic target molecule C/EBP homology protein (CHOP) of ATF-4 was upregulated and hippocampal neuronal apoptosis was induced by copper exposure. Taken together, we propose that chronic copper exposure might cause spatial memory impairment, selective loss of synaptic proteins, and neuronal apoptosis through the mechanisms involving activation of PKR/eIF2α signaling pathway.

  12. Expression of inactive glutathione peroxidase 4 leads to embryonic lethality, and inactivation of the Alox15 gene does not rescue such knock-in mice.

    Science.gov (United States)

    Brütsch, Simone Hanna; Wang, Chi Chiu; Li, Lu; Stender, Hannelore; Neziroglu, Nilgün; Richter, Constanze; Kuhn, Hartmut; Borchert, Astrid

    2015-02-01

    Glutathione peroxidases (Gpx) and lipoxygenases (Alox) are functional counterplayers in the metabolism of hydroperoxy lipids that regulate cellular redox homeostasis. Gpx4 is a moonlighting protein that has been implicated not only as an enzyme in anti-oxidative defense, gene expression regulation, and programmed cell death, but also as a structural protein in spermatogenesis. Homozygous Gpx4 knock-out mice are not viable, but molecular reasons for intrauterine lethality are not completely understood. This study was aimed at investigating whether the lack of catalytic activity or the impaired function as structural protein is the dominant reason for embryonic lethality. We further explored whether the pro-oxidative enzyme mouse 12/15 lipoxygenase (Alox15) plays a major role in embryonic lethality of Gpx4-deficient mice. To achieve these goals, we first created knock-in mice, which express a catalytically inactive Gpx4 mutant (Sec46Ala). As homozygous Gpx4-knock-out mice Sec46Ala-Gpx4(+/+) knock-in animals are not viable but undergo intrauterine resorption between embryonic day 6 and 7 (E6-7). In contrast, heterozygous knock-in mice (Sec46Ala-Gpx4(-/+)) are viable, fertile and do not show major phenotypic alterations. Interestingly, homozygous Alox15 deficiency did not rescue the U46A-Gpx4(+/+) mice from embryonic lethality. In fact, when heterozygous U46A-Gpx4(-/+) mice were stepwise crossed into an Alox15-deficent background, no viable U46A-Gpx4(+/+)+Alox15(-/-) individuals were obtained. However, we were able to identify U46A-Gpx4(+/+)+Alox15(-/-) embryos in the state of resorption around E7. These data suggest that the lack of catalytic activity is the major reason for the embryonic lethality of Gpx4(-/-) mice and that systemic inactivation of the Alox15 gene does not rescue homozygous knock-in mice expressing catalytically silent Gpx4.

  13. Optimization of an Image-Guided Laser-Induced Choroidal Neovascularization Model in Mice.

    Directory of Open Access Journals (Sweden)

    Yan Gong

    Full Text Available The mouse model of laser-induced choroidal neovascularization (CNV has been used in studies of the exudative form of age-related macular degeneration using both the conventional slit lamp and a new image-guided laser system. A standardized protocol is needed for consistent results using this model, which has been lacking. We optimized details of laser-induced CNV using the image-guided laser photocoagulation system. Four lesions with similar size were consistently applied per eye at approximately double the disc diameter away from the optic nerve, using different laser power levels, and mice of various ages and genders. After 7 days, the mice were sacrificed and retinal pigment epithelium/choroid/sclera was flat-mounted, stained with Isolectin B4, and imaged. Quantification of the area of the laser-induced lesions was performed using an established and constant threshold. Exclusion criteria are described that were necessary for reliable data analysis of the laser-induced CNV lesions. The CNV lesion area was proportional to the laser power levels. Mice at 12-16 weeks of age developed more severe CNV than those at 6-8 weeks of age, and the gender difference was only significant in mice at 12-16 weeks of age, but not in those at 6-8 weeks of age. Dietary intake of omega-3 long-chain polyunsaturated fatty acid reduced laser-induced CNV in mice. Taken together, laser-induced CNV lesions can be easily and consistently applied using the image-guided laser platform. Mice at 6-8 weeks of age are ideal for the laser-induced CNV model.

  14. Three months of high-fructose feeding fails to induce excessive weight gain or leptin resistance in mice.

    Directory of Open Access Journals (Sweden)

    Erik J Tillman

    Full Text Available High-fructose diets have been implicated in obesity via impairment of leptin signaling in humans and rodents. We investigated whether fructose-induced leptin resistance in mice could be used to study the metabolic consequences of fructose consumption in humans, particularly in children and adolescents. Male C57Bl/6 mice were weaned to a randomly assigned diet: high fructose, high sucrose, high fat, or control (sugar-free, low-fat. Mice were maintained on their diets for at least 14 weeks. While fructose-fed mice regularly consumed more kcal and expended more energy, there was no difference in body weight compared to control by the end of the study. Additionally, after 14 weeks, both fructose-fed and control mice displayed similar leptin sensitivity. Fructose-feeding also did not change circulating glucose, triglycerides, or free fatty acids. Though fructose has been linked to obesity in several animal models, our data fail to support a role for fructose intake through food lasting 3 months in altering of body weight and leptin signaling in mice. The lack of impact of fructose in the food of growing mice on either body weight or leptin sensitivity over this time frame was surprising, and important information for researchers interested in fructose and body weight regulation.

  15. Conjugated Linoleic Acid Ameliorates Inflammation-Induced Colorectal Cancer in Mice through Activation of PPARγ1–3

    Science.gov (United States)

    Evans, Nicholas P.; Misyak, Sarah A.; Schmelz, Eva M.; Guri, Amir J.; Hontecillas, Raquel; Bassaganya-Riera, Josep

    2010-01-01

    Conjugated linoleic acid (CLA) exerts a protective effect on experimental inflammatory bowel disease and shows promise as a chemopreventive agent against colorectal cancer (CRC) in mice, although the mechanisms by which it exerts its beneficial effects against malignancies in the gut are not completely understood. Mice lacking PPARγ in immune and epithelial cells and PPARγ-expressing littermates were fed either control or CLA-supplemented (1 g CLA/100 g) diets to determine the role of PPARγ in inflammation-induced CRC. To induce tumor formation and colitis, mice were treated with azoxymethane and then challenged with 2% dextran sodium sulfate, respectively. Dietary CLA ameliorated disease activity, decreased colitis, and prevented adenocarcinoma formation in the PPARγ-expressing floxed mice but not in the tissue-specific PPARγ-null mice. Dietary CLA supplementation significantly decreased the percentages of macrophages in the mesenteric lymph nodes (MLN) regardless of the genotype and increased regulatory T cell numbers in MLN of PPARγ-expressing, but not in the tissue-specific, PPARγ-null mice. Colonic tumor necrosis factor-α mRNA expression was significantly suppressed in CLA-fed, PPARγ-expressing mice. This study suggests CLA ameliorates colitis and prevents tumor formation in part through a PPARγ-dependent mechanism. PMID:20089779

  16. Lack of collagen VI promotes neurodegeneration by impairing autophagy and inducing apoptosis during aging.

    Science.gov (United States)

    Cescon, Matilde; Chen, Peiwen; Castagnaro, Silvia; Gregorio, Ilaria; Bonaldo, Paolo

    2016-05-01

    Collagen VI is an extracellular matrix (ECM) protein with a broad distribution in different tissues and mostly deposited at the close periphery of the cell surface. Previous studies revealed that collagen VI protects neurons from the toxicity of amyloid-βpeptides and from UV-induced damage. However, the physiological role of this protein in the central nervous system (CNS) remains unknown. Here, we established primary neural cultures from murine cortex and hippocampus, and carried out in vitro and in vivo studies in wild-type and collagen VI null (Col6a1-/-) mice. Col6a1-/- neural cultures displayed an increased incidence of spontaneous apoptosis and higher vulnerability to oxidative stress, accompanied by altered regulation of autophagy with increased p62 protein levels and decreased LC3 lipidation. Analysis of brain sections confirmed increased apoptosis and abnormal regulation of autophagy in the CNS of collagen VI-deficient animals. To investigate the in vivo physiological consequences of these CNS defects, we carried out functional studies and found that motor and memory task performances were impaired in aged Col6a1-/-mice. These findings indicate that lack of collagen VI leads to spontaneous apoptosis and defective autophagy in neural cells, and point at a protective role for this ECM protein in the CNS during physiological aging.

  17. Radiation carcinogenesis in radiosensitive mutant Scid mice

    International Nuclear Information System (INIS)

    Ogiu, Toshiaki; Ishii-Ohba, Hiroko; Kobayashi, Shigeru; Nishimura, Mayumi; Shimada, Yoshiya; Tsuji, Hideo; Watanabe, Fumiaki; Suzuki, Fumio; Sado, Toshihiko

    2000-01-01

    The Scid mice were established as a severe combined immunodeficient mouse strain lacking both T- and B-cell functions. Scid (homozygote), its parent strain C.B-17 (wild-type) and their hybrid F1 (heterozygote) were used for analysis of the relationship between sensitivity to acute effects of ionizing radiation and radiation-tumor development. Acute effects were studied using γ-rays and LD 50(30) was found to be 4.05 Gy in Scid, 6.5 Gy in F1 and 7.2 Gy in C.B-17. When bone marrow cells were irradiated with X-rays in vitro, survival curves of C.B-17 and F1 cells showed a region of shoulder with D 0 =0.68 and 0.67 Gy, respectively, while those of Scid were of no shoulder with D 0 =0.46 Gy. Scid mice died due to tumors (most were thymic lymphoma, T/L) 20-40 weeks after irradiation with 1-3 Gy γ-rays but C.B-17 and F1 survived longer. Bone marrow transplantation was found effective to prevent the radiation T/L. FACS analysis for surface antigens of those T/L cells suggested the change of Ras oncogenes. The change of Notch 1 gene was suggested by Southern hybridization and thus a possible role of defective DNA-PK in mice alone (not in rats and humans) was suggested as well. (K.H.)

  18. Lack of immunoglobulin M suppression by immunoglobulin G antibody in thymectomized, irradiated, and bone marrow-reconstituted mice infected with Toxoplasma gondii.

    OpenAIRE

    Aryanpour, J; Hafizi, A; Modabber, F

    1980-01-01

    Thymectomized, irradiated, bone marrow-reconstituted (T-deprived) mie infected with an avirulent strain of Toxoplasma gondii produced antibody titers comparable to those produced in intact syngeneic mice. Both immunoglobulin M (IgM) and IgG antibodies were produced in T-deprived animals; however, the IgM antibody remained constant in the presence of increasing amounts of IgG. In the intact animals, IgM became undetectable by day 50 postinfection as expected. Feedback inhibition of IgM by IgG ...

  19. Mice lacking the p75 receptor fail to acquire a normal complement of taste buds and geniculate ganglion neurons by adulthood

    OpenAIRE

    Krimm, Robin F.

    2006-01-01

    Brain derived neurotrophic factor and neurotrophin-4 are required for normal taste bud development. Although these neurotrophins normally function via the tyrosine kinase receptor, trkB, they also bind to the pan-neurotrophin receptor, p75. The goal of the present study was to determine whether the p75 receptor is required for the development or maintenance of a full complement of adult taste buds. Mice with p75 null mutations lose 34% of their circumvallate taste buds, 36% of their fungiform...

  20. Brain serotonin signaling does not determine sexual preference in male mice.

    Directory of Open Access Journals (Sweden)

    Mariana Angoa-Pérez

    Full Text Available It was reported recently that male mice lacking brain serotonin (5-HT lose their preference for females (Liu et al., 2011, Nature, 472, 95-100, suggesting a role for 5-HT signaling in sexual preference. Regulation of sex preference by 5-HT lies outside of the well established roles in this behavior established for the vomeronasal organ (VNO and the main olfactory epithelium (MOE. Presently, mice with a null mutation in the gene for tryptophan hydroxylase 2 (TPH2, which are depleted of brain 5-HT, were tested for sexual preference. When presented with inanimate (urine scents from male or estrous female or animate (male or female mouse in estrus sexual stimuli, TPH2-/- males show a clear preference for female over male stimuli. When a TPH2-/- male is offered the simultaneous choice between an estrous female and a male mouse, no sexual preference is expressed. However, when confounding behaviors that are seen among 3 mice in the same cage are controlled, TPH2-/- mice, like their TPH2+/+ counterparts, express a clear preference for female mice. Female TPH2-/- mice are preferred by males over TPH2+/+ females but this does not lead to increased pregnancy success. In fact, if one or both partners in a mating pair are TPH2-/- in genotype, pregnancy success rates are significantly decreased. Finally, expression of the VNO-specific cation channel TRPC2 and of CNGA2 in the MOE of TPH2-/- mice is normal, consistent with behavioral findings that sexual preference of TPH2-/- males for females is intact. In conclusion, 5-HT signaling in brain does not determine sexual preference in male mice. The use of pharmacological agents that are non-selective for the 5-HT neuronal system and that have serious adverse effects may have contributed historically to the stance that 5-HT regulates sexual behavior, including sex partner preference.

  1. Laminin alpha2 deficiency and muscular dystrophy; genotype-phenotype correlation in mutant mice

    DEFF Research Database (Denmark)

    Guo, L T; Zhang, X U; Kuang, W

    2003-01-01

    2, lacking domain VI. Interestingly, all mutants lack laminin alpha2 in peripheral nerve. We have demonstrated previously, that overexpression of the human laminin alpha2 in skeletal muscle in dy(2J)/dy(2J) and dy(W)/dy(W) mice under the control of a striated muscle-specific creatine kinase promoter......Deficiency of laminin alpha2 is the cause of one of the most severe muscular dystrophies in humans and other species. It is not yet clear how particular mutations in the laminin alpha2 chain gene affect protein expression, and how abnormal levels or structure of the protein affect disease. Animal...

  2. Project management web tools at the MICE experiment

    International Nuclear Information System (INIS)

    Coney, L R; Tunnell, C D

    2012-01-01

    Project management tools like Trac are commonly used within the open-source community to coordinate projects. The Muon Ionization Cooling Experiment (MICE) uses the project management web application Redmine to host mice.rl.ac.uk. Many groups within the experiment have a Redmine project: analysis, computing and software (including offline, online, controls and monitoring, and database subgroups), executive board, and operations. All of these groups use the website to communicate, track effort, develop schedules, and maintain documentation. The issue tracker is a rich tool that is used to identify tasks and monitor progress within groups on timescales ranging from immediate and unexpected problems to milestones that cover the life of the experiment. It allows the prioritization of tasks according to time-sensitivity, while providing a searchable record of work that has been done. This record of work can be used to measure both individual and overall group activity, identify areas lacking sufficient personnel or effort, and as a measure of progress against the schedule. Given that MICE, like many particle physics experiments, is an international community, such a system is required to allow easy communication within a global collaboration. Unlike systems that are purely wiki-based, the structure of a project management tool like Redmine allows information to be maintained in a more structured and logical fashion.

  3. Neutralisation of uPA with a monoclonal antibody reduces plasmin formation and delays skin wound healing in tPA-deficient mice

    DEFF Research Database (Denmark)

    Jögi, Annika; Rønø, Birgitte; Lund, Ida K

    2010-01-01

    Proteolytic degradation by plasmin and metalloproteinases is essential for epidermal regeneration in skin wound healing. Plasminogen deficient mice have severely delayed wound closure as have mice simultaneously lacking the two plasminogen activators, urokinase-type plasminogen activator (u......PA) and tissue-type plasminogen activator (tPA). In contrast, individual genetic deficiencies in either uPA or tPA lead to wound healing kinetics with no or only slightly delayed closure of skin wounds....

  4. Proconvulsant effects of the ketogenic diet in electroshock-induced seizures in mice.

    Science.gov (United States)

    Zarnowska, Iwona; Luszczki, Jarogniew J; Zarnowski, Tomasz; Wlaz, Piotr; Czuczwar, Stanislaw J; Gasior, Maciej

    2017-04-01

    Among non-pharmacological treatments, the ketogenic diet (KD) has the strongest demonstrated evidence of clinical success in drug resistant epilepsy. In an attempt to model the anticonvulsant effects of the KD pre-clinically, the present study assessed the effects of the KD against electroshock-induced convulsions in mice. After confirming that exposure to the KD for 2 weeks resulted in stable ketosis and hypoglycemia, mice were exposed to electroshocks of various intensities to establish general seizure susceptibility. When compared to mice fed the standard rodent chow diet (SRCD), we found that mice fed the KD were more sensitive to electroconvulsions as reflected by a significant decrease in seizure threshold (3.86 mA in mice on the KD vs 7.29 mA in mice on the SRCD; P < 0.05) in the maximal electroshock seizure threshold (MEST) test. To examine if this increased seizure sensitivity to electroconvulsions produced by the KD would affect anticonvulsant effects of antiepileptic drugs (AEDs), anticonvulsant potencies of carbamazepine (CBZ), phenobarbital (PB), phenytoin (PHT), and valproate (VPA) against maximal electroshock (MES)-induced convulsions were compared in mice fed the KD and SRCD. We found that potencies of all AEDs studied were decreased in mice fed the KD in comparison to those on the SRCD, with decreases in the anticonvulsant potencies ranging from 1.4 fold (PB) to 1.7 fold (PHT). Finally, the lack of differences in brain exposures of the AEDs studied in mice fed the KD and SRCD ruled out a pharmacokinetic nature of the observed findings. Taken together, exposure to the KD in the present study had an overall pro-convulsant effect. Since electroconvulsions require large metabolic reserves to support their rapid spread throughout the brain and consequent generalized tonic-clonic convulsions, this effect may be explained by a high energy state produced by the KD in regards to increased energy storage and utilization.

  5. Acetylated tubulin is essential for touch sensation in mice.

    Science.gov (United States)

    Morley, Shane J; Qi, Yanmei; Iovino, Loredana; Andolfi, Laura; Guo, Da; Kalebic, Nereo; Castaldi, Laura; Tischer, Christian; Portulano, Carla; Bolasco, Giulia; Shirlekar, Kalyanee; Fusco, Claudia M; Asaro, Antonino; Fermani, Federica; Sundukova, Mayya; Matti, Ulf; Reymond, Luc; De Ninno, Adele; Businaro, Luca; Johnsson, Kai; Lazzarino, Marco; Ries, Jonas; Schwab, Yannick; Hu, Jing; Heppenstall, Paul A

    2016-12-13

    At its most fundamental level, touch sensation requires the translation of mechanical energy into mechanosensitive ion channel opening, thereby generating electro-chemical signals. Our understanding of this process, especially how the cytoskeleton influences it, remains unknown. Here we demonstrate that mice lacking the α-tubulin acetyltransferase Atat1 in sensory neurons display profound deficits in their ability to detect mechanical stimuli. We show that all cutaneous afferent subtypes, including nociceptors have strongly reduced mechanosensitivity upon Atat1 deletion, and that consequently, mice are largely insensitive to mechanical touch and pain. We establish that this broad loss of mechanosensitivity is dependent upon the acetyltransferase activity of Atat1, which when absent leads to a decrease in cellular elasticity. By mimicking α-tubulin acetylation genetically, we show both cellular rigidity and mechanosensitivity can be restored in Atat1 deficient sensory neurons. Hence, our results indicate that by influencing cellular stiffness, α-tubulin acetylation sets the force required for touch.

  6. Implementation of a manual for working with wobbler mice and criteria for discontinuation of the experiment

    DEFF Research Database (Denmark)

    Ott, Bastian; Dahlke, Carolin; Meller, Karl

    2015-01-01

    . This article is designed to summarize conscientious work with the wobbler mouse, a model for the sporadic form of amyotrophic lateral sclerosis. This mouse model is characterized by a degeneration of α-motor-neurons leading to head tremor, loss of body weight and rapidly progressive paralysis. Although...... this mouse model has been known since 1956, there are no guidelines for breeding wobbler mice. Due to the lack of such guidelines the present study tries to close this gap and implements a manual for further studies. It includes the whole workflow in regard to wobbler mice from breeding and animal care...

  7. Role of the adiponectin binding protein, T-cadherin (Cdh13, in allergic airways responses in mice.

    Directory of Open Access Journals (Sweden)

    Alison S Williams

    Full Text Available Adiponectin is an adipose derived hormone that declines in obesity. We have previously shown that exogenous administration of adiponectin reduces allergic airways responses in mice. T-cadherin (T-cad; Cdh13 is a binding protein for the high molecular weight isoforms of adiponectin. To determine whether the beneficial effects of adiponectin on allergic airways responses require T-cad, we sensitized wildtype (WT, T-cadherin deficient (T-cad(-/- and adiponectin and T-cad bideficient mice to ovalbumin (OVA and challenged the mice with aerosolized OVA or PBS. Compared to WT, T-cad(-/- mice were protected against OVA-induced airway hyperresponsiveness, increases in BAL inflammatory cells, and induction of IL-13, IL-17, and eotaxin expression. Histological analysis of the lungs of OVA-challenged T-cad(-/- versus WT mice indicated reduced inflammation around the airways, and reduced mucous cell hyperplasia. Combined adiponectin and T-cad deficiency reversed the effects of T-cad deficiency alone, indicating that the observed effects of T-cad deficiency require adiponectin. Compared to WT, serum adiponectin was markedly increased in T-cad(-/- mice, likely because adiponectin that is normally sequestered by endothelial T-cad remains free in the circulation. In conclusion, T-cad does not mediate the protective effects of adiponectin. Instead, mice lacking T-cad have reduced allergic airways disease, likely because elevated serum adiponectin levels act on other adiponectin signaling pathways.

  8. Differing impact of the deletion of hemochromatosis-associated molecules HFE and transferrin receptor-2 on the iron phenotype of mice lacking bone morphogenetic protein 6 or hemojuvelin.

    Science.gov (United States)

    Latour, Chloé; Besson-Fournier, Céline; Meynard, Delphine; Silvestri, Laura; Gourbeyre, Ophélie; Aguilar-Martinez, Patricia; Schmidt, Paul J; Fleming, Mark D; Roth, Marie-Paule; Coppin, Hélène

    2016-01-01

    Hereditary hemochromatosis, which is characterized by inappropriately low levels of hepcidin, increased dietary iron uptake, and systemic iron accumulation, has been associated with mutations in the HFE, transferrin receptor-2 (TfR2), and hemojuvelin (HJV) genes. However, it is still not clear whether these molecules intersect in vivo with bone morphogenetic protein 6 (BMP6)/mothers against decapentaplegic (SMAD) homolog signaling, the main pathway up-regulating hepcidin expression in response to elevated hepatic iron. To answer this question, we produced double knockout mice for Bmp6 and β2-microglobulin (a surrogate for the loss of Hfe) and for Bmp6 and Tfr2, and we compared their phenotype (hepcidin expression, Bmp/Smad signaling, hepatic and extrahepatic tissue iron accumulation) with that of single Bmp6-deficient mice and that of mice deficient for Hjv, alone or in combination with Hfe or Tfr2. Whereas the phenotype of Hjv-deficient females was not affected by loss of Hfe or Tfr2, that of Bmp6-deficient females was considerably worsened, with decreased Smad5 phosphorylation, compared with single Bmp6-deficient mice, further repression of hepcidin gene expression, undetectable serum hepcidin, and massive iron accumulation not only in the liver but also in the pancreas, the heart, and the kidneys. These results show that (1) BMP6 does not require HJV to transduce signal to hepcidin in response to intracellular iron, even if the loss of HJV partly reduces this signal, (2) another BMP ligand can replace BMP6 and significantly induce hepcidin expression in response to extracellular iron, and (3) BMP6 alone is as efficient at inducing hepcidin as the other BMPs in association with the HJV/HFE/TfR2 complex; they provide an explanation for the compensatory effect of BMP6 treatment on the molecular defect underlying Hfe hemochromatosis in mice. © 2015 by the American Association for the Study of Liver Diseases.

  9. Toll-like receptor 4-positive macrophages protect mice from Pasteurella pneumotropica-induced pneumonia

    Science.gov (United States)

    Hart, Marcia L.; Mosier, Derek A.; Chapes, Stephen K.

    2003-01-01

    This study investigates Toll-like receptor 4 (TLR4)-positive macrophages in early recognition and clearance of pulmonary bacteria. TLR4 is a trans-membrane receptor that is the primary recognition molecule for lipopolysaccharide of gram-negative bacteria. The TLR4(Lps-del) mouse strains C57BL10/ScN (B10) and STOCK Abb(tm1) TLR4(Lps-del) Slc11a1(s)(B10 x C2D) are susceptible to pulmonary infections and develop pneumonia when naturally or experimentally infected by the opportunistic bacterium Pasteurella pneumotropica. Since these mice have the TLR4(Lps-del) genotype, we hypothesized that reconstitution of mice with TLR4-positive macrophages would provide resistance to this bacterium. A cultured macrophage cell line (C2D macrophages) and bone marrow cells from C2D mice were adoptively transferred to B10 and B10 x C2D mice by intraperitoneal injection. C2D macrophages increased B10 and B10 x C2D mouse resistance to P. pneumotropica. In C2D-recipient mice there was earlier transcription of tumor necrosis factor alpha and chemokines JE and macrophage inflammatory protein 2 (MIP-2) in the lungs of B10 and B10 x C2D mice, and there was earlier transcription of KC and MIP-1alpha in B10 x C2D mice. In addition, the course of inflammation following experimental Pasteurella challenge was altered in C2D recipients. C2D macrophages also protected B10 x C2D mice, which lack CD4(+) T cells. These data indicate that macrophages are critical for pulmonary immunity and can provide host resistance to P. pneumotropica. This study indicates that TLR4-positive macrophages are important for early recognition and clearance of pulmonary bacterial infections.

  10. Effects of muscarinic receptor antagonists on cocaine discrimination in wild-type mice and in muscarinic receptor M1, M2, and M4 receptor knockout mice.

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    Joseph, Lauren; Thomsen, Morgane

    2017-06-30

    Muscarinic M 1 /M 4 receptor stimulation can reduce abuse-related effects of cocaine and may represent avenues for treating cocaine addiction. Muscarinic antagonists can mimic and enhance effects of cocaine, including discriminative stimulus (S D ) effects, but the receptor subtypes mediating those effects are not known. A better understanding of the complex cocaine/muscarinic interactions is needed to evaluate and develop potential muscarinic-based medications. Here, knockout mice lacking M 1 , M 2 , or M 4 receptors (M 1 -/- , M 2 -/- , M 4 -/- ), as well as control wild-type mice and outbred Swiss-Webster mice, were trained to discriminate 10mg/kg cocaine from saline. Muscarinic receptor antagonists with no subtype selectivity (scopolamine), or preferential affinity at the M 1 , M 2 , or M 4 subtype (telenzepine, trihexyphenidyl; methoctramine, AQ-RA 741; tropicamide) were tested alone and in combination with cocaine. In intact animals, antagonists with high affinity at M 1 /M 4 receptors partially substituted for cocaine and increased the S D effect of cocaine, while M 2 -preferring antagonists did not substitute, and reduced the S D effect of cocaine. The cocaine-like effects of scopolamine were absent in M 1 -/- mice. The cocaine S D attenuating effects of methoctramine were absent in M 2 -/- mice and almost absent in M 1 -/- mice. The findings indicate that the cocaine-like S D effects of muscarinic antagonists are primarily mediated through M 1 receptors, with a minor contribution of M 4 receptors. The data also support our previous findings that stimulation of M 1 receptors and M 4 receptors can each attenuate the S D effect of cocaine, and show that this can also be achieved by blocking M 2 autoreceptors, likely via increased acetylcholine release. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Lack of collagen XVIII/endostatin exacerbates immune-mediated glomerulonephritis.

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    Hamano, Yuki; Okude, Takashi; Shirai, Ryota; Sato, Ikumi; Kimura, Ryota; Ogawa, Makoto; Ueda, Yoshihiko; Yokosuka, Osamu; Kalluri, Raghu; Ueda, Shiro

    2010-09-01

    Collagen XVIII is a component of the highly specialized extracellular matrix associated with basement membranes of epithelia and endothelia. In the normal kidney, collagen XVIII is distributed throughout glomerular and tubular basement membranes, mesangial matrix, and Bowman's capsule. Proteolytic cleavage within its C-terminal domain releases the fragment endostatin, which has antiangiogenic properties. Because damage to the glomerular basement membrane (GBM) accompanies immune-mediated renal injury, we investigated the role of collagen XVIII/endostatin in this disorder. We induced anti-GBM glomerulonephritis in collagen XVIII alpha1-null and wild-type mice and compared the resulting matrix accumulation, inflammation, and capillary rarefaction. Anti-GBM disease upregulated collagen XVIII/endostatin expression within the GBM and Bowman's capsule of wild-type mice. Collagen XVIII/endostatin-deficient mice developed more severe glomerular and tubulointerstitial injury than wild-type mice. Collagen XVIII/endostatin deficiency altered matrix remodeling, enhanced the inflammatory response, and promoted capillary rarefaction and vascular endothelial cell damage, but did not affect endothelial proliferation. Supplementing collagen XVIII-deficient mice with exogenous endostatin did not affect the progression of anti-GBM disease. Taken together, these results suggest that collagen XVIII/endostatin preserves the integrity of the extracellular matrix and capillaries in the kidney, protecting against progressive glomerulonephritis.

  12. Nutritional intervention restores muscle but not kidney phenotypes in adult calcineurin Aα null mice.

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    Kirsten Madsen

    Full Text Available Mice lacking the α isoform of the catalytic subunit of calcineurin (CnAα were first reported in 1996 and have been an important model to understand the role of calcineurin in the brain, immune system, bones, muscle, and kidney. Research using the mice has been limited, however, by failure to thrive and early lethality of most null pups. Work in our laboratory led to the rescue of CnAα-/- mice by supplemental feeding to compensate for a defect in salivary enzyme secretion. The data revealed that, without intervention, knockout mice suffer from severe caloric restriction. Since nutritional deprivation is known to significantly alter development, it is imperative that previous conclusions based on CnAα-/- mice are revisited to determine which aspects of the phenotype were attributable to caloric restriction versus a direct role for CnAα. In this study, we find that defects in renal development and function persist in adult CnAα-/- mice including a significant decrease in glomerular filtration rate and an increase in blood urea nitrogen levels. These data indicate that impaired renal development we previously reported was not due to caloric restriction but rather a specific role for CnAα in renal development and function. In contrast, we find that rather than being hypoglycemic, rescued mice are mildly hyperglycemic and insulin resistant. Examination of muscle fiber types shows that previously reported reductions in type I muscle fibers are no longer evident in rescued null mice. Rather, loss of CnAα likely alters insulin response due to a reduction in insulin receptor substrate-2 (IRS2 expression and signaling in muscle. This study illustrates the importance of re-examining the phenotypes of CnAα-/- mice and the advances that are now possible with the use of adult, rescued knockout animals.

  13. IL-1 receptor-antagonist (IL-1Ra) knockout mice show anxiety-like behavior by aging.

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    Wakabayashi, Chisato; Numakawa, Tadahiro; Odaka, Haruki; Ooshima, Yoshiko; Kiyama, Yuji; Manabe, Toshiya; Kunugi, Hiroshi; Iwakura, Yoichiro

    2015-07-10

    Interleukin 1 (IL-1) plays a critical role in stress responses, and its mRNA is induced in the brain by restraint stress. Previously, we reported that IL-1 receptor antagonist (IL-1Ra) knockout (KO) mice, which lacked IL-1Ra molecules that antagonize the IL-1 receptor, showed anti-depression-like behavior via adrenergic modulation at the age of 8 weeks. Here, we report that IL-1Ra KO mice display an anxiety-like phenotype that is induced spontaneously by aging in the elevated plus-maze (EPM) test. This anxiety-like phenotype was improved by the administration of diazepam. The expression of the anxiety-related molecule glucocorticoid receptor (GR) was significantly reduced in 20-week-old but not in 11-week-old IL-1Ra KO mice compared to wild-type (WT) littermates. The expression of the mineralocorticoid receptor (MR) was not altered between IL-1Ra KO mice and WT littermates at either 11 or 20 weeks old. Analysis of monoamine concentration in the hippocampus revealed that tryptophan, the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), and the dopamine metabolite homovanillic acid (HVA) were significantly increased in 20-week-old IL-1Ra KO mice compared to littermate WT mice. These findings strongly suggest that the anxiety-like behavior observed in older mice was caused by the complicated alteration of monoamine metabolism and/or GR expression in the hippocampus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Absence of ERK5/MAPK7 delays tumorigenesis in Atm−/− mice

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    Rovira-Clavé, Xavier; Gamez, Celina Paola Vasquez; Soriano, Francesc X.; Reina, Manuel; Espel, Enric

    2016-01-01

    Ataxia-telangiectasia mutated (ATM) is a cell cycle checkpoint kinase that upon activation by DNA damage leads to cell cycle arrest and DNA repair or apoptosis. The absence of Atm or the occurrence of loss-of-function mutations in Atm predisposes to tumorigenesis. MAPK7 has been implicated in numerous types of cancer with pro-survival and pro-growth roles in tumor cells, but its functional relation with tumor suppressors is not clear. In this study, we show that absence of MAPK7 delays death due to spontaneous tumor development in Atm−/− mice. Compared with Atm−/− thymocytes, Mapk7−/−Atm−/− thymocytes exhibited an improved response to DNA damage (increased phosphorylation of H2AX) and a restored apoptotic response after treatment of mice with ionizing radiation. These findings define an antagonistic function of ATM and MAPK7 in the thymocyte response to DNA damage, and suggest that the lack of MAPK7 inhibits thymic lymphoma growth in Atm−/− mice by partially restoring the DNA damage response in thymocytes. PMID:27793024

  15. Asic3(-/- female mice with hearing deficit affects social development of pups.

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    Wei-Li Wu

    Full Text Available BACKGROUND: Infant crying is an important cue for mothers to respond adequately. Inappropriate response to infant crying can hinder social development in infants. In rodents, the pup-mother interaction largely depends on pup's calls. Mouse pups emit high frequency to ultrasonic vocalization (2-90 kHz to communicate with their dam for maternal care. However, little is known about how the maternal response to infant crying or pup calls affects social development over the long term. METHODOLOGY/PRINCIPAL FINDINGS: Here we used mice lacking acid-sensing ion channel 3 (Asic3(-/- to create a hearing deficit to probe the effect of caregiver hearing on maternal care and adolescent social development. Female Asic3(-/- mice showed elevated hearing thresholds for low to ultrasonic frequency (4-32 kHz on auditory brain stem response, which thus hindered their response to their pups' wriggling calls and ultrasonic vocalization, as well as their retrieval of pups. In adolescence, pups reared by Asic3(-/- mice showed a social deficit in juvenile social behaviors as compared with those reared by wild-type or heterozygous dams. The social-deficit phenotype in juvenile mice reared by Asic3(-/- mice was associated with the reduced serotonin transmission of the brain. However, Asic3(-/- pups cross-fostered to wild-type dams showed rescued social deficit. CONCLUSIONS/SIGNIFICANCE: Inadequate response to pups' calls as a result of ASIC3-dependent hearing loss confers maternal deficits in caregivers and social development deficits in their young.

  16. Abnormalities in brain structure and behavior in GSK-3alpha mutant mice

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    Kaidanovich-Beilin Oksana

    2009-11-01

    Full Text Available Abstract Background Glycogen synthase kinase-3 (GSK-3 is a widely expressed and highly conserved serine/threonine protein kinase encoded by two genes that generate two related proteins: GSK-3α and GSK-3β. Mice lacking a functional GSK-3α gene were engineered in our laboratory; they are viable and display insulin sensitivity. In this study, we have characterized brain functions of GSK-3α KO mice by using a well-established battery of behavioral tests together with neurochemical and neuroanatomical analysis. Results Similar to the previously described behaviours of GSK-3β+/-mice, GSK-3α mutants display decreased exploratory activity, decreased immobility time and reduced aggressive behavior. However, genetic inactivation of the GSK-3α gene was associated with: decreased locomotion and impaired motor coordination, increased grooming activity, loss of social motivation and novelty; enhanced sensorimotor gating and impaired associated memory and coordination. GSK-3α KO mice exhibited a deficit in fear conditioning, however memory formation as assessed by a passive avoidance test was normal, suggesting that the animals are sensitized for active avoidance of a highly aversive stimulus in the fear-conditioning paradigm. Changes in cerebellar structure and function were observed in mutant mice along with a significant decrease of the number and size of Purkinje cells. Conclusion Taken together, these data support a role for the GSK-3α gene in CNS functioning and possible involvement in the development of psychiatric disorders.

  17. Phospholipid composition and longevity: lessons from Ames dwarf mice.

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    Valencak, Teresa G; Ruf, Thomas

    2013-12-01

    Membrane fatty acid (FA) composition is correlated with longevity in mammals. The "membrane pacemaker hypothesis of ageing" proposes that animals which cellular membranes contain high amounts of polyunsaturated FAs (PUFAs) have shorter life spans because their membranes are more susceptible to peroxidation and further oxidative damage. It remains to be shown, however, that long-lived phenotypes such as the Ames dwarf mouse have membranes containing fewer PUFAs and thus being less prone to peroxidation, as would be predicted from the membrane pacemaker hypothesis of ageing. Here, we show that across four different tissues, i.e., muscle, heart, liver and brain as well as in liver mitochondria, Ames dwarf mice possess membrane phospholipids containing between 30 and 60 % PUFAs (depending on the tissue), which is similar to PUFA contents of their normal-sized, short-lived siblings. However, we found that that Ames dwarf mice membrane phospholipids were significantly poorer in n-3 PUFAs. While lack of a difference in PUFA contents is contradicting the membrane pacemaker hypothesis, the lower n-3 PUFAs content in the long-lived mice provides some support for the membrane pacemaker hypothesis of ageing, as n-3 PUFAs comprise those FAs being blamed most for causing oxidative damage. By comparing tissue composition between 1-, 2- and 6-month-old mice in both phenotypes, we found that membranes differed both in quantity of PUFAs and in the prevalence of certain PUFAs. In sum, membrane composition in the Ames dwarf mouse supports the concept that tissue FA composition is related to longevity.

  18. Impaired Coronary and Renal Vascular Function in Spontaneously Type 2 Diabetic Leptin-Deficient Mice.

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    Helena U Westergren

    Full Text Available Type 2 diabetes is associated with macro- and microvascular complications in man. Microvascular dysfunction affects both cardiac and renal function and is now recognized as a main driver of cardiovascular mortality and morbidity. However, progression of microvascular dysfunction in experimental models is often obscured by macrovascular pathology and consequently demanding to study. The obese type 2 diabetic leptin-deficient (ob/ob mouse lacks macrovascular complications, i.e. occlusive atherosclerotic disease, and may therefore be a potential model for microvascular dysfunction. The present study aimed to test the hypothesis that these mice with an insulin resistant phenotype might display microvascular dysfunction in both coronary and renal vascular beds.In this study we used non-invasive Doppler ultrasound imaging to characterize microvascular dysfunction during the progression of diabetes in ob/ob mice. Impaired coronary flow velocity reserve was observed in the ob/ob mice at 16 and 21 weeks of age compared to lean controls. In addition, renal resistivity index as well as pulsatility index was higher in the ob/ob mice at 21 weeks compared to lean controls. Moreover, plasma L-arginine was lower in ob/ob mice, while asymmetric dimethylarginine was unaltered. Furthermore, a decrease in renal vascular density was observed in the ob/ob mice.In parallel to previously described metabolic disturbances, the leptin-deficient ob/ob mice also display cardiac and renal microvascular dysfunction. This model may therefore be suitable for translational, mechanistic and interventional studies to improve the understanding of microvascular complications in type 2 diabetes.

  19. Antigenicity of Leishmania-Activated C-Kinase Antigen (LACK in Human Peripheral Blood Mononuclear Cells, and Protective Effect of Prime-Boost Vaccination With pCI-neo-LACK Plus Attenuated LACK-Expressing Vaccinia Viruses in Hamsters

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    Laura Fernández

    2018-04-01

    Full Text Available Leishmania-activated C-kinase antigen (LACK is a highly conserved protein among Leishmania species and is considered a viable vaccine candidate for human leishmaniasis. In animal models, prime-boost vaccination with LACK-expressing plasmids plus attenuated vaccinia viruses (modified vaccinia Ankara [MVA] and mutant M65 expressing LACK, has been shown to protect against cutaneous leishmaniasis (CL. Further, LACK demonstrated to induce the production of protective cytokines in patients with active CL or cured visceral leishmaniasis, as well as in asymptomatic individuals from endemic areas. However, whether LACK is capable to trigger cytokine release by peripheral blood mononuclear cells from patients cured of CL due to Leishmania infantum (L. infantum or induce protection in L. infantum-infected hamsters [visceral leishmaniasis (VL model], has not yet been analyzed. The present work examines the ex vivo immunogenicity of LACK in cured VL and CL patients, and asymptomatic subjects from an L. infantum area. It also evaluates the vaccine potential of LACK against L. infantum infection in hamsters, in a protocol of priming with plasmid pCI-neo-LACK (DNA-LACK followed by a booster with the poxvirus vectors MVA-LACK or M65-LACK. LACK-stimulated PBMC from both asymptomatic and cured subjects responded by producing IFN-γ, TNF-α, and granzyme B (Th1-type response. Further, 78% of PBMC samples that responded to soluble Leishmania antigen showed IFN-γ secretion following stimulation with LACK. In hamsters, the protocol of DNA-LACK prime/MVA-LACK or M65-LACK virus boost vaccination significantly reduced the amount of Leishmania DNA in the liver and bone marrow, with no differences recorded between the use of MVA or M65 virus vector options. In summary, the Th1-type and cytotoxic responses elicited by LACK in PBMC from human subjects infected with L. infantum, and the parasite protective effect of prime/boost vaccination in hamsters with DNA-LACK/MVA-LACK

  20. Uncaria rhynchophylla ameliorates cognitive deficits induced by D-galactose in mice.

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    Xian, Yan-Fang; Lin, Zhi-Xiu; Zhao, Ming; Mao, Qing-Qiu; Ip, Siu-Po; Che, Chun-Tao

    2011-12-01

    The stem with hooks of Uncaria rhynchophylla is a component herb of many traditional formulae for the treatment of neurodegenerative diseases. However, scientific evidence of the efficacy of Uncaria rhynchophylla in the treatment of Alzheimer's disease (AD) in animal models is lacking. Thus, in the present study, we investigated whether the 70 % aqueous ethanol extract of Uncaria rhynchophylla (EUR) could protect against D-galactose (D-gal)-induced cognitive deficits in mice. Mice were given a subcutaneous injection of D-gal (50 mg/kg) and orally administered EUR (100, 200, or 400 mg/kg) daily for 8 weeks. The effect of EUR on D-gal-induced cognitive deficits was evaluated by measuring behavioral and neurochemical parameters of AD and the antioxidant status of brain tissue. The results showed that EUR (200 or 400 mg/kg) significantly increased exploratory behavior (assessed by an open-field test) and improved spatial learning and memory function (assessed by the Morris water maze test) in D-gal-treated mice. In addition, EUR (200 or 400 mg/kg) significantly increased the levels of acetylcholine and glutathione and decreased the activity of acetylcholinesterase and the level of malondialdehyde in the brains of D-gal-treated mice. These results indicate that EUR ameliorates cognitive deficits induced by D-gal in mice, and that this action may be mediated, at least in part, by the inhibition of acetylcholinesterase activity and the enhancement of the antioxidant status of brain tissue. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Impaired social behavior in 5-HT3A receptor knockout mice

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    Laura A Smit-Rigter

    2010-11-01

    Full Text Available The 5-HT3 receptor is a ligand-gated ion channel expressed on interneurons throughout the brain. So far, analysis of the 5-HT3A knockout mouse revealed changes in nociceptive processing and a reduction in anxiety related behavior. Recently, it was shown that the 5-HT3 receptor is also expressed on Cajal-Retzius cells which play a key role in cortical development and that knockout mice lacking this receptor showed aberrant growth of the dendritic tree of cortical layer II/III pyramidal neurons. Other mouse models in which serotonergic signaling was disrupted during development showed similar morphological changes in the cortex, and in addition, also deficits in social behavior. Here, we subjected male and female 5-HT3A knockout mice and their non-transgenic littermates to several tests of social behavior. We found that 5-HT3A knockout mice display impaired social communication in the social transmission of food preference task. Interestingly, we showed that in the social interaction test only female 5-HT3A knockout mice spent less time in reciprocal social interaction starting after 5 minutes of testing. Moreover, we observed differences in preference for social novelty for male and female 5-HT3A knockout mice during the social approach test. However, no changes in olfaction, exploratory activity and anxiety were detected. These results indicate that the 5-HT3A knockout mouse displays impaired social behavior with specific changes in males and females, reminiscent to other mouse models in which serotonergic signaling is disturbed in the developing brain.

  2. Obif, a Transmembrane Protein, Is Required for Bone Mineralization and Spermatogenesis in Mice.

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    Koji Mizuhashi

    Full Text Available Various kinds of transmembrane and secreted proteins play pivotal roles in development through cell-cell communication. We previously reported that Obif (Osteoblast induction factor, Tmem119, encoding a single transmembrane protein, is expressed in differentiating osteoblasts, and that Obif-/- mice exhibit significantly reduced bone volume in the femur. In the current study, we characterized the Obif protein and further investigated the biological phenotypes of a variety of tissues in Obif-/- mice.First, we found that O-glycosylation of the Obif protein occurs at serine residue 36 in the Obif extracellular domain. Next, we observed that Obif-/- mice exhibit bone dysplasia in association with significantly increased osteoid volume per osteoid surface (OV/OS and osteoid maturation time (Omt, and significantly decreased mineral apposition rate (MAR and bone formation rate per bone surface (BFR/BS. In addition, we observed that Obif-/- mice show a significant decrease in testis weight as well as in sperm number. By histological analysis, we found that Obif is expressed in spermatocytes and spermatids in the developing testis and that spermatogenesis is halted at the round spermatid stage in the Obif-/- testis that lacks sperm. However, the number of litters fathered by male mice was slightly reduced in Obif-/- mice compared with wild-type mice, although this was not statistically significant.Our results, taken together with previous observations, indicate that Obif is a type Ia transmembrane protein whose N-terminal region is O-glycosylated. In addition, we found that Obif is required for normal bone mineralization and late testicular differentiation in vivo. These findings suggest that Obif plays essential roles in the development of multiple tissues.

  3. Overactivation of Hedgehog Signaling Alters Development of the Ovarian Vasculature in Mice1

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    Ren, Yi; Cowan, Robert G.; Migone, Fernando F.; Quirk, Susan M.

    2012-01-01

    ABSTRACT The hedgehog (HH) signaling pathway is critical for ovarian function in Drosophila, but its role in the mammalian ovary has not been defined. Previously, expression of a dominant active allele of the HH signal transducer protein smoothened (SMO) in Amhr2cre/+SmoM2 mice caused anovulation in association with a lack of smooth muscle in the theca of developing follicles. The current study examined events during the first 2 wk of life in Amhr2cre/+SmoM2 mice to gain insight into the cause of anovulation. Expression of transcriptional targets of HH signaling, Gli1, Ptch1, and Hhip, which are used as measures of pathway activity, were elevated during the first several days of life in Amhr2cre/+SmoM2 mice compared to controls but were similar to controls in older mice. Microarray analysis showed that genes with increased expression in 2-day-old mutants compared to controls were enriched for the processes of vascular and tube development and steroidogenesis. The density of platelet endothelial cell adhesion molecule (PECAM)-labeled endothelial tubes was increased in the cortex of newborn ovaries of mutant mice. Costaining of preovulatory follicles for PECAM and smooth muscle actin showed that muscle-type vascular support cells are deficient in theca of mutant mice. Expression of genes for steroidogenic enzymes that are normally expressed in the fetal adrenal gland were elevated in newborn ovaries of mutant mice. In summary, overactivation of HH signaling during early life alters gene expression and vascular development and this is associated with the lifelong development of anovulatory follicles in which the thecal vasculature fails to mature appropriately. PMID:22402963

  4. Deletion of circadian gene Per1 alleviates acute ethanol-induced hepatotoxicity in mice

    International Nuclear Information System (INIS)

    Wang, Tao; Yang, Ping; Zhan, Yibei; Xia, Lin; Hua, Zichun; Zhang, Jianfa

    2013-01-01

    The severity of ethanol-induced liver injury is associated with oxidative stress and lipid accumulation in the liver. Core circadian clock is known to mediate antioxidative enzyme activity and lipid metabolism. However, the link between circadian clock and ethanol-induced hepatotoxicity remains unclear. Here we showed that extents of acute ethanol-induced liver injury and steatosis in mice exhibit circadian variations consistent with hepatic expression of Period (Per) genes. Mice lacking clock gene Per1 displayed less susceptible to ethanol-induced liver injury, as evidenced by lower serum transaminase activity and less severe histopathological changes. Ethanol-induced lipid peroxidation was alleviated in Per1−/− mice. However, Per1 deletion had no effect on antioxidants depletion caused by ethanol administration. Ethanol-induced triglycerides (TG) accumulation in the serum and liver was significantly decreased in Per1−/− mice compared with that in wild-type (WT) mice. Analysis of gene expression in the liver revealed peroxisome proliferators activated receptor-gamma (PPARγ) and its target genes related to TG synthesis are remarkably down-regulated in Per1−/− mice. HepG2 cells were treated with ethanol at 150 mM for 3 days. Per1 overexpression augmented lipid accumulation after treatment with ethanol in HepG2 cells, but had no effect on ethanol-induced oxidative stress. Expression of genes related to lipogenesis, including PPARγ and its target genes, was up-regulated in cells overexpressing Per1. In conclusion, these results indicated that circadian rhythms of ethanol-induced hepatotoxicity are controlled by clock gene Per1, and deletion of Per1 protected mice from ethanol-induced liver injury by decreasing hepatic lipid accumulation

  5. Obif, a Transmembrane Protein, Is Required for Bone Mineralization and Spermatogenesis in Mice.

    Science.gov (United States)

    Mizuhashi, Koji; Chaya, Taro; Kanamoto, Takashi; Omori, Yoshihiro; Furukawa, Takahisa

    2015-01-01

    Various kinds of transmembrane and secreted proteins play pivotal roles in development through cell-cell communication. We previously reported that Obif (Osteoblast induction factor, Tmem119), encoding a single transmembrane protein, is expressed in differentiating osteoblasts, and that Obif-/- mice exhibit significantly reduced bone volume in the femur. In the current study, we characterized the Obif protein and further investigated the biological phenotypes of a variety of tissues in Obif-/- mice. First, we found that O-glycosylation of the Obif protein occurs at serine residue 36 in the Obif extracellular domain. Next, we observed that Obif-/- mice exhibit bone dysplasia in association with significantly increased osteoid volume per osteoid surface (OV/OS) and osteoid maturation time (Omt), and significantly decreased mineral apposition rate (MAR) and bone formation rate per bone surface (BFR/BS). In addition, we observed that Obif-/- mice show a significant decrease in testis weight as well as in sperm number. By histological analysis, we found that Obif is expressed in spermatocytes and spermatids in the developing testis and that spermatogenesis is halted at the round spermatid stage in the Obif-/- testis that lacks sperm. However, the number of litters fathered by male mice was slightly reduced in Obif-/- mice compared with wild-type mice, although this was not statistically significant. Our results, taken together with previous observations, indicate that Obif is a type Ia transmembrane protein whose N-terminal region is O-glycosylated. In addition, we found that Obif is required for normal bone mineralization and late testicular differentiation in vivo. These findings suggest that Obif plays essential roles in the development of multiple tissues.

  6. Differential effects of diazepam and MPEP on habituation and neuro-behavioural processes in inbred mice.

    Science.gov (United States)

    Salomons, Amber R; Pinzon, Nathaly Espitia; Boleij, Hetty; Kirchhoff, Susanne; Arndt, Saskia S; Nordquist, Rebecca E; Lindemann, Lothar; Jaeschke, Georg; Spooren, Will; Ohl, Frauke

    2012-06-11

    Previous studies have demonstrated a profound lack of habituation in 129P3 mice compared to the habituating, but initially more anxious, BALB/c mice. The present study investigated whether this non-adaptive phenotype of 129P3 mice is primarily based on anxiety-related characteristics. To test this hypothesis and extend our knowledge on the behavioural profile of 129P3 mice, the effects of the anxiolyticdiazepam (1, 3 and 5 mg/kg) and the putative anxiolytic metabotropic glutamate receptor 5 (mGlu5R) antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP, 3, 10 and 30 mg/kg) treatment on within-trial (intrasession) habituation, object recognition (diazepam: 1 mg/kg; MPEP 10 mg/kg) and on the central-nervous expression of the immediate early gene c-Fos (diazepam: 1 mg/kg; MPEP 10 mg/kg) were investigated. Behavioural findings validated the initially high, but habituating phenotype of BALB/c mice, while 129P3 mice were characterized by impaired intrasession habituation. Diazepam had an anxiolytic effect in BALB/c mice, while in higher doses caused behavioural inactivity in 129P3 mice. MPEP revealed almost no anxiolytic effects on behaviour in both strains, but reduced stress-induced corticosterone responses only in 129P3 mice. These results were complemented by reduced expression of c-Fos after MPEP treatment in brain areas related to emotional processes, and increased c-Fos expression in higher integrating brain areas such as the prelimbic cortex compared to vehicle-treated 129P3 mice. These results suggest that the strain differences observed in (non)adaptive anxiety behaviour are at least in part mediated by differences in gamma-aminobutyric acid- A and mGluR5 mediated transmission.

  7. Abnormal grooming activity in Dab1(scm) (scrambler) mutant mice.

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    Strazielle, C; Lefevre, A; Jacquelin, C; Lalonde, R

    2012-07-15

    Dab1(scm) mutant mice, characterized by cell ectopias and degeneration in cerebellum, hippocampus, and neocortex, were compared to non-ataxic controls for different facets of grooming caused by brief water immersions, as well as some non-grooming behaviors. Dab1(scm) mutants were strongly affected in their quantitative functional parameters, exhibiting higher starting latencies before grooming relative to non-ataxic littermates of the A/A strain, fewer grooming bouts, and grooming components of shorter duration, with an unequal regional distribution targeting almost totally the rostral part (head washing and forelimb licking) of the animal. Only bouts of a single grooming element were preserved. The cephalocaudal order of grooming elements appeared less disorganized, mutant and control mice initiating the grooming with head washing and forelimb licking prior to licking posterior parts. However, mutants differed from controls in that all their bouts were incomplete but uninterrupted, although intergroup difference for percentage of the incorrect transitions was not significant. In contrast to grooming, Dab1(scm) mice ambulated for a longer time. During walking episodes, they exhibited more body scratching than controls, possibly to compensate for the lack of licking different body parts. In conjunction with studies with other ataxic mice, these results indicate that the cerebellar cortex affects grooming activity and is consequently involved in executing various components, but not in its sequential organization, which requires other brain regions such as cerebral cortices or basal ganglia. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Cutaneous C-polymodal fibers lacking TRPV1 are sensitized to heat following inflammation, but fail to drive heat hyperalgesia in the absence of TPV1 containing C-heat fibers

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    Koerber H Richard

    2010-09-01

    Full Text Available Abstract Background Previous studies have shown that the TRPV1 ion channel plays a critical role in the development of heat hyperalgesia after inflammation, as inflamed TRPV1-/- mice develop mechanical allodynia but fail to develop thermal hyperalgesia. In order to further investigate the role of TRPV1, we have used an ex vivo skin/nerve/DRG preparation to examine the effects of CFA-induced-inflammation on the response properties of TRPV1-positive and TRPV1-negative cutaneous nociceptors. Results In wildtype mice we found that polymodal C-fibers (CPMs lacking TRPV1 were sensitized to heat within a day after CFA injection. This sensitization included both a drop in average heat threshold and an increase in firing rate to a heat ramp applied to the skin. No changes were observed in the mechanical response properties of these cells. Conversely, TRPV1-positive mechanically insensitive, heat sensitive fibers (CHs were not sensitized following inflammation. However, results suggested that some of these fibers may have gained mechanical sensitivity and that some previous silent fibers gained heat sensitivity. In mice lacking TRPV1, inflammation only decreased heat threshold of CPMs but did not sensitize their responses to the heat ramp. No CH-fibers could be identified in naïve nor inflamed TRPV1-/- mice. Conclusions Results obtained here suggest that increased heat sensitivity in TRPV1-negative CPM fibers alone following inflammation is insufficient for the induction of heat hyperalgesia. On the other hand, TRPV1-positive CH fibers appear to play an essential role in this process that may include both afferent and efferent functions.

  9. Enhanced growth and improved vascular function in offspring from successive pregnancies in endothelial nitric oxide synthase knockout mice

    NARCIS (Netherlands)

    Longo, M; Jain, [No Value; Langenveld, J; Vedernikov, YP; Garfield, RE; Hankins, GDV; Anderson, GD; Saade, GR

    2004-01-01

    Objective: Transgenic mice that lack endothelial nitric oxide synthase have offspring with growth deficiency and abnormal vascular reactivity in later life. Our objective was to evaluate the role of parity in the modulation of the fetal programming of growth and vascular responses in these

  10. The ERa-PI3K cascade in proopiomelanocortin progenitor neurons regulates feeding and glucose balance in female mice

    Science.gov (United States)

    Estrogens act upon estrogen receptor (ER)a to inhibit feeding and improve glucose homeostasis in female animals. However, the intracellular signals that mediate these estrogenic actions remain unknown. Here, we report that anorexigenic effects of estrogens are blunted in female mice that lack ERa sp...

  11. Litter environment affects behavior and brain metabolic activity of adult knockout mice

    Directory of Open Access Journals (Sweden)

    David Crews

    2009-08-01

    Full Text Available In mammals, the formative environment for social and anxiety-related behaviors is the family unit; in the case of rodents, this is the litter and the mother-young bond. A deciding factor in this environment is the sex ratio of the litter and, in the case of mice lacking functional copies of gene(s, the ratio of the various genotypes in the litter. Both Sex and Genotype ratios of the litter affect the nature and quality of the individual’s behavior later in adulthood, as well as metabolic activity in brain nuclei that underlie these behaviors. Mice were raised in litters reconstituted shortly after to birth to control for Sex ratio and Genotype ratio (wild type pups vs. pups lacking a functional estrogen receptor α. In both males and females the Sex and Genotype of siblings in the litter affected aggressive behaviors as well as patterns of metabolic activity in limbic nuclei in the social behavior network later in adulthood. Further, this pattern in males varied depending upon the Genotype of their brothers and sisters. Principal Components Analysis revealed two components comprised of several amygdalar and hypothalamic nuclei; the VMH showed strong correlations in both clusters, suggesting its pivotal nature in the organization of two neural networks.

  12. Effect of thumus cell injections on germinal center formation in lymphoid tissues of nude (thymusless) mice. [X radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, E.B.; Caporale, L.H.; Thorbecke, G.J.

    1974-09-01

    Nude mice, partially backcrossed to Balb/c or DBA/2, were injected iv with 5 x 10/sup 7/ thymus cells from the respective inbred strain. The response of these mice to immunization with Brucella abortus antigen was studied, with respect to both antibody production and the formation of germinal centers in their lymphoid tissues. The results were compared to those obtained with nude mice to which no thymus cells were given, as well as to Balb/c, DBA/2, or +/question litter mate controls. Nude mice formed less 19S as well as 7S antibody than did litter mate controls and completely lacked germinal centers in lymph nodes and gut-associated lymphoid tissue. Those nude mice which had been injected with thymus cells made a much better secondary response, both for 19S and for 7S antibody, and had active germinal centers in their lymph nodes as early as 3 wk after thymus cell injection. Intestinal lymphoid tissue in nude mice showed only slight reconstitution of germinal center activity several months after thymus cell injection and none at earlier times. Irradiated (3000 R) thymus cells appeared as effective as normal cells in facilitating germinal center appearance and 7S antibody production in the nude mice.

  13. The intestinal flora is required to support antibody responses to systemic immunization in infant and germ free mice.

    Science.gov (United States)

    Lamousé-Smith, Esi S; Tzeng, Alice; Starnbach, Michael N

    2011-01-01

    The presence of a complex and diverse intestinal flora is functionally important for regulating intestinal mucosal immune responses. However, the extent to which a balanced intestinal flora regulates systemic immune responses is still being defined. In order to specifically examine whether the acquisition of a less complex flora influences responses to immunization in the pre-weaning stages of life, we utilize a model in which infant mice acquire an intestinal flora from their mothers that has been altered by broad-spectrum antibiotics. In this model, pregnant dams are treated with a cocktail of antibiotics that alters both the density and microbial diversity of the intestinal flora. After challenge with a subcutaneous immunization, the antibiotic altered flora infant mice have lower antigen specific antibody titers compared to control age-matched mice. In a second model, we examined germ free (GF) mice to analyze how the complete lack of flora influences the ability to mount normal antibody responses following subcutaneous immunization. GF mice do not respond well to immunization and introduction of a normal flora into GF mice restores the capacity of these mice to respond. These results indicate that a gastrointestinal flora reduced in density and complexity at critical time points during development adversely impacts immune responses to systemic antigens.

  14. A homolog of Drosophila grainy head is essential for epidermal integrity in mice.

    Science.gov (United States)

    Ting, Stephen B; Caddy, Jacinta; Hislop, Nikki; Wilanowski, Tomasz; Auden, Alana; Zhao, Lin-Lin; Ellis, Sarah; Kaur, Pritinder; Uchida, Yoshikazu; Holleran, Walter M; Elias, Peter M; Cunningham, John M; Jane, Stephen M

    2005-04-15

    The Drosophila cuticle is essential for maintaining the surface barrier defenses of the fly. Integral to cuticle resilience is the transcription factor grainy head, which regulates production of the enzyme required for covalent cross-linking of the cuticular structural components. We report that formation and maintenance of the epidermal barrier in mice are dependent on a mammalian homolog of grainy head, Grainy head-like 3. Mice lacking this factor display defective skin barrier function and deficient wound repair, accompanied by reduced expression of transglutaminase 1, the key enzyme involved in cross-linking the structural components of the superficial epidermis. These findings suggest that the functional mechanisms involving protein cross-linking that maintain the epidermal barrier and induce tissue repair are conserved across 700 million years of evolution.

  15. Improved Insulin Sensitivity despite Increased Visceral Adiposity in Mice Deficient for the Immune Cell Transcription Factor T-bet

    Science.gov (United States)

    Stolarczyk, Emilie; Vong, Chi Teng; Perucha, Esperanza; Jackson, Ian; Cawthorne, Michael A.; Wargent, Edward T.; Powell, Nick; Canavan, James B.; Lord, Graham M.; Howard, Jane K.

    2013-01-01

    Summary Low-grade inflammation in fat is associated with insulin resistance, although the mechanisms are unclear. We report that mice deficient in the immune cell transcription factor T-bet have lower energy expenditure and increased visceral fat compared with wild-type mice, yet paradoxically are more insulin sensitive. This striking phenotype, present in young T-bet−/− mice, persisted with high-fat diet and increasing host age and was associated with altered immune cell numbers and cytokine secretion specifically in visceral adipose tissue. However, the favorable metabolic phenotype observed in T-bet-deficient hosts was lost in T-bet−/− mice also lacking adaptive immunity (T-bet−/−xRag2−/−), demonstrating that T-bet expression in the adaptive rather than the innate immune system impacts host glucose homeostasis. Indeed, adoptive transfer of T-bet-deficient, but not wild-type, CD4+ T cells to Rag2−/− mice improved insulin sensitivity. Our results reveal a role for T-bet in metabolic physiology and obesity-associated insulin resistance. PMID:23562076

  16. Contribution of CaMKIV to injury and fear- induced ultrasonic vocalizations in adult mice

    Directory of Open Access Journals (Sweden)

    Zhuo Min

    2005-03-01

    Full Text Available Abstract Calcium-calmodulin dependent protein kinase IV (CaMKIV is a protein kinase that activates the transcription factor CREB. Our previous work demonstrated that mice lacking CaMKIV had a defect in fear memory while behavioral responses to noxious stimuli were unchanged. Here, we measured ultrasonic vocalizations (USVs before and after fear conditioning and in response to a noxious injection of capsaicin to measure behavioral responses to emotional stimuli. Consistent with previous findings, behavioral nociceptive responses to capsaicin were undistinguishable between wild-type and CaMKIV-/- mice. Wild-type animals showed a selective increase in 50 kHz USVs in response to capsaicin while such an increase was absent in CaMKIV-/- mice. The foot shock given during fear conditioning caused an increase in 30 kHz USVs in both wild-type and CaMKIV-/- mice. When returned to the context one hour later, USVs from the wild-type were significantly decreased. Additionally, the onset of a tone, which had previously been paired with the foot shock, caused a significant decrease in USVs during auditory conditioning. CaMKIV-/- mice showed significantly less reduction in USVs when placed in the same context three days after receiving the shock, consistent with the decrease in freezing reported previously. Our results provide a new approach for investigating the molecular mechanism for emotional vocalization in mice and suggest that CaMKIV dependent signaling pathways play an important role in the emotional response to pain and fear.

  17. Fucosylation Deficiency in Mice Leads to Colitis and Adenocarcinoma.

    Science.gov (United States)

    Wang, Yiwei; Huang, Dan; Chen, Kai-Yuan; Cui, Min; Wang, Weihuan; Huang, Xiaoran; Awadellah, Amad; Li, Qing; Friedman, Ann; Xin, William W; Di Martino, Luca; Cominelli, Fabio; Miron, Alex; Chan, Ricky; Fox, James G; Xu, Yan; Shen, Xiling; Kalady, Mathew F; Markowitz, Sanford; Maillard, Ivan; Lowe, John B; Xin, Wei; Zhou, Lan

    2017-01-01

    De novo synthesis of guanosine diphosphate (GDP)-fucose, a substrate for fucosylglycans, requires sequential reactions mediated by GDP-mannose 4,6-dehydratase (GMDS) and GDP-4-keto-6-deoxymannose 3,5-epimerase-4-reductase (FX or tissue specific transplantation antigen P35B [TSTA3]). GMDS deletions and mutations are found in 6%-13% of colorectal cancers; these mostly affect the ascending and transverse colon. We investigated whether a lack of fucosylation consequent to loss of GDP-fucose synthesis contributes to colon carcinogenesis. FX deficiency and GMDS deletion produce the same biochemical phenotype of GDP-fucose deficiency. We studied a mouse model of fucosylation deficiency (Fx-/- mice) and mice with the full-length Fx gene (controls). Mice were placed on standard chow or fucose-containing diet (equivalent to a control fucosylglycan phenotype). Colon tissues were collected and analyzed histologically or by enzyme-linked immunosorbent assays to measure cytokine levels; T cells also were collected and analyzed. Fecal samples were analyzed by 16s ribosomal RNA sequencing. Mucosal barrier function was measured by uptake of fluorescent dextran. We transplanted bone marrow cells from Fx-/- or control mice (Ly5.2) into irradiated 8-week-old Fx-/- or control mice (Ly5.1). We performed immunohistochemical analyses for expression of Notch and the hes family bHLH transcription factor (HES1) in colon tissues from mice and a panel of 60 human colorectal cancer specimens (27 left-sided, 33 right-sided). Fx-/- mice developed colitis and serrated-like lesions. The intestinal pathology of Fx-/- mice was reversed by addition of fucose to the diet, which restored fucosylation via a salvage pathway. In the absence of fucosylation, dysplasia appeared and progressed to adenocarcinoma in up to 40% of mice, affecting mainly the right colon and cecum. Notch was not activated in Fx-/- mice fed standard chow, leading to decreased expression of its target Hes1. Fucosylation deficiency

  18. Severe osteogenesis imperfecta in cyclophilin B-deficient mice.

    Directory of Open Access Journals (Sweden)

    Jae Won Choi

    2009-12-01

    Full Text Available Osteogenesis Imperfecta (OI is a human syndrome characterized by exquisitely fragile bones due to osteoporosis. The majority of autosomal dominant OI cases result from point or splice site mutations in the type I collagen genes, which are thought to lead to aberrant osteoid within developing bones. OI also occurs in humans with homozygous mutations in Prolyl-3-Hydroxylase-1 (LEPRE1. Although P3H1 is known to hydroxylate a single residue (pro-986 in type I collagen chains, it is unclear how this modification acts to facilitate collagen fibril formation. P3H1 exists in a complex with CRTAP and the peptidyl-prolyl isomerase cyclophilin B (CypB, encoded by the Ppib gene. Mutations in CRTAP cause OI in mice and humans, through an unknown mechanism, while the role of CypB in this complex has been a complete mystery. To study the role of mammalian CypB, we generated mice lacking this protein. Early in life, Ppib-/- mice developed kyphosis and severe osteoporosis. Collagen fibrils in Ppib-/- mice had abnormal morphology, further consistent with an OI phenotype. In vitro studies revealed that in CypB-deficient fibroblasts, procollagen did not localize properly to the golgi. We found that levels of P3H1 were substantially reduced in Ppib-/- cells, while CRTAP was unaffected by loss of CypB. Conversely, knockdown of either P3H1 or CRTAP did not affect cellular levels of CypB, but prevented its interaction with collagen in vitro. Furthermore, knockdown of CRTAP also caused depletion of cellular P3H1. Consistent with these changes, post translational prolyl-3-hydroxylation of type I collagen by P3H1 was essentially absent in CypB-deficient cells and tissues from CypB-knockout mice. These data provide significant new mechanistic insight into the pathophysiology of OI and reveal how the members of the P3H1/CRTAP/CypB complex interact to direct proper formation of collagen and bone.

  19. Severe Osteogenesis Imperfecta in Cyclophilin B–Deficient Mice

    Science.gov (United States)

    Choi, Jae Won; Sutor, Shari L.; Lindquist, Lonn; Evans, Glenda L.; Madden, Benjamin J.; Bergen, H. Robert; Hefferan, Theresa E.; Yaszemski, Michael J.; Bram, Richard J.

    2009-01-01

    Osteogenesis Imperfecta (OI) is a human syndrome characterized by exquisitely fragile bones due to osteoporosis. The majority of autosomal dominant OI cases result from point or splice site mutations in the type I collagen genes, which are thought to lead to aberrant osteoid within developing bones. OI also occurs in humans with homozygous mutations in Prolyl-3-Hydroxylase-1 (LEPRE1). Although P3H1 is known to hydroxylate a single residue (pro-986) in type I collagen chains, it is unclear how this modification acts to facilitate collagen fibril formation. P3H1 exists in a complex with CRTAP and the peptidyl-prolyl isomerase cyclophilin B (CypB), encoded by the Ppib gene. Mutations in CRTAP cause OI in mice and humans, through an unknown mechanism, while the role of CypB in this complex has been a complete mystery. To study the role of mammalian CypB, we generated mice lacking this protein. Early in life, Ppib-/- mice developed kyphosis and severe osteoporosis. Collagen fibrils in Ppib-/- mice had abnormal morphology, further consistent with an OI phenotype. In vitro studies revealed that in CypB–deficient fibroblasts, procollagen did not localize properly to the golgi. We found that levels of P3H1 were substantially reduced in Ppib-/- cells, while CRTAP was unaffected by loss of CypB. Conversely, knockdown of either P3H1 or CRTAP did not affect cellular levels of CypB, but prevented its interaction with collagen in vitro. Furthermore, knockdown of CRTAP also caused depletion of cellular P3H1. Consistent with these changes, post translational prolyl-3-hydroxylation of type I collagen by P3H1 was essentially absent in CypB–deficient cells and tissues from CypB–knockout mice. These data provide significant new mechanistic insight into the pathophysiology of OI and reveal how the members of the P3H1/CRTAP/CypB complex interact to direct proper formation of collagen and bone. PMID:19997487

  20. Severe osteogenesis imperfecta in cyclophilin B-deficient mice.

    Science.gov (United States)

    Choi, Jae Won; Sutor, Shari L; Lindquist, Lonn; Evans, Glenda L; Madden, Benjamin J; Bergen, H Robert; Hefferan, Theresa E; Yaszemski, Michael J; Bram, Richard J

    2009-12-01

    Osteogenesis Imperfecta (OI) is a human syndrome characterized by exquisitely fragile bones due to osteoporosis. The majority of autosomal dominant OI cases result from point or splice site mutations in the type I collagen genes, which are thought to lead to aberrant osteoid within developing bones. OI also occurs in humans with homozygous mutations in Prolyl-3-Hydroxylase-1 (LEPRE1). Although P3H1 is known to hydroxylate a single residue (pro-986) in type I collagen chains, it is unclear how this modification acts to facilitate collagen fibril formation. P3H1 exists in a complex with CRTAP and the peptidyl-prolyl isomerase cyclophilin B (CypB), encoded by the Ppib gene. Mutations in CRTAP cause OI in mice and humans, through an unknown mechanism, while the role of CypB in this complex has been a complete mystery. To study the role of mammalian CypB, we generated mice lacking this protein. Early in life, Ppib-/- mice developed kyphosis and severe osteoporosis. Collagen fibrils in Ppib-/- mice had abnormal morphology, further consistent with an OI phenotype. In vitro studies revealed that in CypB-deficient fibroblasts, procollagen did not localize properly to the golgi. We found that levels of P3H1 were substantially reduced in Ppib-/- cells, while CRTAP was unaffected by loss of CypB. Conversely, knockdown of either P3H1 or CRTAP did not affect cellular levels of CypB, but prevented its interaction with collagen in vitro. Furthermore, knockdown of CRTAP also caused depletion of cellular P3H1. Consistent with these changes, post translational prolyl-3-hydroxylation of type I collagen by P3H1 was essentially absent in CypB-deficient cells and tissues from CypB-knockout mice. These data provide significant new mechanistic insight into the pathophysiology of OI and reveal how the members of the P3H1/CRTAP/CypB complex interact to direct proper formation of collagen and bone.

  1. Shp2 in Forebrain Neurons Regulates Synaptic Plasticity, Locomotion, and Memory Formation in Mice

    Science.gov (United States)

    Kusakari, Shinya; Saitow, Fumihito; Ago, Yukio; Shibasaki, Koji; Sato-Hashimoto, Miho; Matsuzaki, Yasunori; Kotani, Takenori; Murata, Yoji; Hirai, Hirokazu; Matsuda, Toshio; Suzuki, Hidenori

    2015-01-01

    Shp2 (Src homology 2 domain-containing protein tyrosine phosphatase 2) regulates neural cell differentiation. It is also expressed in postmitotic neurons, however, and mutations of Shp2 are associated with clinical syndromes characterized by mental retardation. Here we show that conditional-knockout (cKO) mice lacking Shp2 specifically in postmitotic forebrain neurons manifest abnormal behavior, including hyperactivity. Novelty-induced expression of immediate-early genes and activation of extracellular-signal-regulated kinase (Erk) were attenuated in the cerebral cortex and hippocampus of Shp2 cKO mice, suggestive of reduced neuronal activity. In contrast, ablation of Shp2 enhanced high-K+-induced Erk activation in both cultured cortical neurons and synaptosomes, whereas it inhibited that induced by brain-derived growth factor in cultured neurons. Posttetanic potentiation and paired-pulse facilitation were attenuated and enhanced, respectively, in hippocampal slices from Shp2 cKO mice. The mutant mice also manifested transient impairment of memory formation in the Morris water maze. Our data suggest that Shp2 contributes to regulation of Erk activation and synaptic plasticity in postmitotic forebrain neurons and thereby controls locomotor activity and memory formation. PMID:25713104

  2. Reduced bone mass and muscle strength in male 5α-reductase type 1 inactivated mice.

    Directory of Open Access Journals (Sweden)

    Sara H Windahl

    Full Text Available Androgens are important regulators of bone mass but the relative importance of testosterone (T versus dihydrotestosterone (DHT for the activation of the androgen receptor (AR in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2, encoded by separate genes (Srd5a1 and Srd5a2. 5α-reductase type 2 is predominantly expressed in male reproductive tissues whereas 5α-reductase type 1 is highly expressed in liver and moderately expressed in several other tissues including bone. The aim of the present study was to investigate the role of 5α-reductase type 1 for bone mass using Srd5a1⁻/⁻ mice. Four-month-old male Srd5a1⁻/⁻ mice had reduced trabecular bone mineral density (-36%, p<0.05 and cortical bone mineral content (-15%, p<0.05 but unchanged serum androgen levels compared with wild type (WT mice. The cortical bone dimensions were reduced in the male Srd5a1⁻/⁻ mice as a result of a reduced cortical periosteal circumference compared with WT mice. T treatment increased the cortical periosteal circumference (p<0.05 in orchidectomized WT mice but not in orchidectomized Srd5a1⁻/⁻ mice. Male Srd5a1⁻/⁻ mice demonstrated a reduced forelimb muscle grip strength compared with WT mice (p<0.05. Female Srd5a1⁻/⁻ mice had slightly increased cortical bone mass associated with elevated circulating levels of androgens. In conclusion, 5α-reductase type 1 inactivated male mice have reduced bone mass and forelimb muscle grip strength and we propose that these effects are due to lack of 5α-reductase type 1 expression in bone and muscle. In contrast, the increased cortical bone mass in female Srd5a1⁻/⁻ mice, is an indirect effect mediated by elevated circulating androgen levels.

  3. Differences in ultrasonic vocalizations between wild and laboratory California mice (Peromyscus californicus.

    Directory of Open Access Journals (Sweden)

    Matina C Kalcounis-Rueppell

    Full Text Available BACKGROUND: Ultrasonic vocalizations (USVs emitted by muroid rodents, including laboratory mice and rats, are used as phenotypic markers in behavioral assays and biomedical research. Interpretation of these USVs depends on understanding the significance of USV production by rodents in the wild. However, there has never been a study of muroid rodent ultrasound function in the wild and comparisons of USVs produced by wild and laboratory rodents are lacking to date. Here, we report the first comparison of wild and captive rodent USVs recorded from the same species, Peromyscus californicus. METHODOLOGY AND PRINCIPAL FINDINGS: We used standard ultrasound recording techniques to measure USVs from California mice in the laboratory (Peromyscus Genetic Stock Center, SC, USA and the wild (Hastings Natural History Reserve, CA, USA. To determine which California mouse in the wild was vocalizing, we used a remote sensing method that used a 12-microphone acoustic localization array coupled with automated radio telemetry of all resident Peromyscus californicus in the area of the acoustic localization array. California mice in the laboratory and the wild produced the same types of USV motifs. However, wild California mice produced USVs that were 2-8 kHz higher in median frequency and significantly more variable in frequency than laboratory California mice. SIGNIFICANCE: The similarity in overall form of USVs from wild and laboratory California mice demonstrates that production of USVs by captive Peromyscus is not an artifact of captivity. Our study validates the widespread use of USVs in laboratory rodents as behavioral indicators but highlights that particular characteristics of laboratory USVs may not reflect natural conditions.

  4. Apoptosis in spermatogonia irradiated P53 null mice

    International Nuclear Information System (INIS)

    Streit-Bianchi, M.; Hendry, J.H.; Roberts, S.A.; Morris, J.D.; Durgaryan, A.A.

    2007-01-01

    Complete text of publication follows. The exposure of germ cells to ionizing radiations is of concern both from high-dose therapeutic exposures and from low doses causing deleterious trans-generational mutations. P53 protein plays an important role in cellular damage and is expressed in the testis normally during meiosis, its expression being localised to the preleptotene and early/mid pachytene spermatocytes. P53 null mice, heterozygotes possessing a 129 Sv/C57BL6 genetic background and B6D2F1 mice have been irradiated to 1 and 2 Gy single doses. Fractionated exposures of 1+1 Gy at 4 hours interval were also carried out. Apoptosis induction, spermatogonia and spermatocytes survival were assessed by microscope analysis of histological samples at 4 to 96 hours after irradiation in time-course experiments. The same end-points were also assessed at 72 and 96 hours after irradiation to single doses in the region between 20cGy to 2Gy. A dose dependent level of p53 expression was observed at 4 hours after irradiation to 1 and 2 Gy which returned to normal level by 24 hours. Our data support a two process mode of apoptosis with a first wave around 12 hours followed by a second wave at 2-3 days. The first wave apoptosis is substantially reduced in p53 null mice whereas the second wave is reduced in B6D2F1 mice. The initial increase in apoptosis was delayed in some stages of the of germ cells development which were identified by the spermatids shape. Clear correlation exists between apoptosis and survival assessed in stage XI-XII Tubules 72 hours after irradiation. The data are in agreement with other data in literature indicating that irradiated spermatogonia die through apoptosis. The lack of apoptosis observed in p53 null mice results in a very high survival rate of daughter cells assessed later. Theses spermatocytes and the following progenitor cells are likely to carry mutations as most will not die in the smaller second wave of apoptosis observed 3 days after

  5. CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity

    OpenAIRE

    Cappel, David A.; Lantier, Louise; Palmisano, Brian T.; Wasserman, David H.; Stafford, John M.

    2015-01-01

    Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases mu...

  6. Loss of stearoyl-CoA desaturase 1 rescues cardiac function in obese leptin-deficient mice.

    Science.gov (United States)

    Dobrzyn, Pawel; Dobrzyn, Agnieszka; Miyazaki, Makoto; Ntambi, James M

    2010-08-01

    The heart of leptin-deficient ob/ob mice is characterized by pathologic left ventricular hypertrophy along with elevated triglyceride (TG) content, increased stearoyl-CoA desaturase (SCD) activity, and increased myocyte apoptosis. In the present study, using an ob/ob;SCD1(-/-) mouse model, we tested the hypothesis that lack of SCD1 could improve steatosis and left ventricle (LV) function in leptin deficiency. We show that disruption of the SCD1 gene improves cardiac function in ob/ob mice by correcting systolic and diastolic dysfunction without affecting levels of plasma TG and FFA. The improvement is associated with reduced expression of genes involved in FA transport and lipid synthesis in the heart, as well as reduction in cardiac FFA, diacylglycerol, TG, and ceramide levels. The rate of FA beta-oxidation is also significantly lower in the heart of ob/ob;SCD1(-/-) mice compared with ob/ob controls. Moreover, SCD1 deficiency reduces cardiac apoptosis in ob/ob mice due to increased expression of antiapoptotic factor Bcl-2 and inhibition of inducible nitric oxide synthase and caspase-3 activities. Reduction in myocardial lipid accumulation and inhibition of apoptosis appear to be one of the main mechanisms responsible for improved LV function in ob/ob mice caused by SCD1 deficiency.

  7. Motor and memory testing of long-lived pregnancy-associated plasma protein--a knock-out mice.

    Science.gov (United States)

    Mason, Emily J; Grell, Jacquelyn A; West, Sally A; Conover, Cheryl A

    2014-12-01

    Mice deficient in pregnancy-associated plasma protein-A (PAPP-A), an IGF binding protein protease, have been shown to be resistant to experimentally induced atherosclerosis and diabetic nephropathy, and, in the laboratory environment, live 30-40% longer than wild-type littermates in association with delayed incidence and occurrence of age-related neoplasms and degenerative diseases. PAPP-A is highly expressed in the cerebellum and hippocampus of the mouse brain. Therefore, the studies presented here were aimed at determining motor behavior, learning and retention in PAPP-A knock-out (KO) mice compared to wild-type (WT) littermates with age. Balance and coordination were assessed using an accelerating rotarod; learning and memory were assessed in a Stone T-maze. Time on the rotarod decreased with age but there was no significant difference between PAPP-A KO and WT mice at any of the testing ages. Latency to reach the goal box and number of errors committed in the Stone T-maze did not change with age and there were no significant differences between PAPP-A KO and WT mice. Lack of PAPP-A in mice did not impact central regulation of coordination, learning or memory. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Mice deficient in CD38 develop an attenuated form of collagen type II-induced arthritis.

    Science.gov (United States)

    Postigo, Jorge; Iglesias, Marcos; Cerezo-Wallis, Daniela; Rosal-Vela, Antonio; García-Rodríguez, Sonia; Zubiaur, Mercedes; Sancho, Jaime; Merino, Ramón; Merino, Jesús

    2012-01-01

    CD38, a type II transmembrane glycoprotein expressed in many cells of the immune system, is involved in cell signaling, migration and differentiation. Studies in CD38 deficient mice (CD38 KO mice) indicate that this molecule controls inflammatory immune responses, although its involvement in these responses depends on the disease model analyzed. Here, we explored the role of CD38 in the control of autoimmune responses using chicken collagen type II (col II) immunized C57BL/6-CD38 KO mice as a model of collagen-induced arthritis (CIA). We demonstrate that CD38 KO mice develop an attenuated CIA that is accompanied by a limited joint induction of IL-1β and IL-6 expression, by the lack of induction of IFNγ expression in the joints and by a reduction in the percentages of invariant NKT (iNKT) cells in the spleen. Immunized CD38 KO mice produce high levels of circulating IgG1 and low of IgG2a anti-col II antibodies in association with reduced percentages of Th1 cells in the draining lymph nodes. Altogether, our results show that CD38 participates in the pathogenesis of CIA controlling the number of iNKT cells and promoting Th1 inflammatory responses.

  9. Mice deficient in CD38 develop an attenuated form of collagen type II-induced arthritis.

    Directory of Open Access Journals (Sweden)

    Jorge Postigo

    Full Text Available CD38, a type II transmembrane glycoprotein expressed in many cells of the immune system, is involved in cell signaling, migration and differentiation. Studies in CD38 deficient mice (CD38 KO mice indicate that this molecule controls inflammatory immune responses, although its involvement in these responses depends on the disease model analyzed. Here, we explored the role of CD38 in the control of autoimmune responses using chicken collagen type II (col II immunized C57BL/6-CD38 KO mice as a model of collagen-induced arthritis (CIA. We demonstrate that CD38 KO mice develop an attenuated CIA that is accompanied by a limited joint induction of IL-1β and IL-6 expression, by the lack of induction of IFNγ expression in the joints and by a reduction in the percentages of invariant NKT (iNKT cells in the spleen. Immunized CD38 KO mice produce high levels of circulating IgG1 and low of IgG2a anti-col II antibodies in association with reduced percentages of Th1 cells in the draining lymph nodes. Altogether, our results show that CD38 participates in the pathogenesis of CIA controlling the number of iNKT cells and promoting Th1 inflammatory responses.

  10. Insulin-Independent GABAA Receptor-Mediated Response in the Barrel Cortex of Mice with Impaired Met Activity.

    Science.gov (United States)

    Lo, Fu-Sun; Erzurumlu, Reha S; Powell, Elizabeth M

    2016-03-30

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder caused by genetic variants, susceptibility alleles, and environmental perturbations. The autism associated geneMETtyrosine kinase has been implicated in many behavioral domains and endophenotypes of autism, including abnormal neural signaling in human sensory cortex. We investigated somatosensory thalamocortical synaptic communication in mice deficient in Met activity in cortical excitatory neurons to gain insights into aberrant somatosensation characteristic of ASD. The ratio of excitation to inhibition is dramatically increased due to decreased postsynaptic GABAAreceptor-mediated inhibition in the trigeminal thalamocortical pathway of mice lacking active Met in the cerebral cortex. Furthermore, in contrast to wild-type mice, insulin failed to increase GABAAreceptor-mediated response in the barrel cortex of mice with compromised Met signaling. Thus, lacking insulin effects may be a risk factor in ASD pathogenesis. A proposed common cause of neurodevelopmental disorders is an imbalance in excitatory neural transmission, provided by the glutamatergic neurons, and the inhibitory signals from the GABAergic interneurons. Many genes associated with autism spectrum disorders impair synaptic transmission in the expected cell type. Previously, inactivation of the autism-associated Met tyrosine kinase receptor in GABAergic interneurons led to decreased inhibition. In thus report, decreased Met signaling in glutamatergic neurons had no effect on excitation, but decimated inhibition. Further experiments indicate that loss of Met activity downregulates GABAAreceptors on glutamatergic neurons in an insulin independent manner. These data provide a new mechanism for the loss of inhibition and subsequent abnormal excitation/inhibition balance and potential molecular candidates for treatment or prevention. Copyright © 2016 the authors 0270-6474/16/363691-07$15.00/0.

  11. Battery of behavioral tests in mice to study postoperative delirium

    Science.gov (United States)

    Peng, Mian; Zhang, Ce; Dong, Yuanlin; Zhang, Yiying; Nakazawa, Harumasa; Kaneki, Masao; Zheng, Hui; Shen, Yuan; Marcantonio, Edward R.; Xie, Zhongcong

    2016-01-01

    Postoperative delirium is associated with increased morbidity, mortality and cost. However, its neuropathogenesis remains largely unknown, partially owing to lack of animal model(s). We therefore set out to employ a battery of behavior tests, including natural and learned behavior, in mice to determine the effects of laparotomy under isoflurane anesthesia (Anesthesia/Surgery) on these behaviors. The mice were tested at 24 hours before and at 6, 9 and 24 hours after the Anesthesia/Surgery. Composite Z scores were calculated. Cyclosporine A, an inhibitor of mitochondria permeability transient pore, was used to determine potential mitochondria-associated mechanisms of these behavioral changes. Anesthesia/Surgery selectively impaired behaviors, including latency to eat food in buried food test, freezing time and time spent in the center in open field test, and entries and duration in the novel arm of Y maze test, with acute onset and various timecourse. The composite Z scores quantitatively demonstrated the Anesthesia/Surgery-induced behavior impairment in mice. Cyclosporine A selectively ameliorated the Anesthesia/Surgery-induced reduction in ATP levels, the increases in latency to eat food, and the decreases in entries in the novel arm. These findings suggest that we could use a battery of behavior tests to establish a mouse model to study postoperative delirium. PMID:27435513

  12. Cell type-specific deficiency of c-kit gene expression in mutant mice of mi/mi genotype.

    Science.gov (United States)

    Isozaki, K.; Tsujimura, T.; Nomura, S.; Morii, E.; Koshimizu, U.; Nishimune, Y.; Kitamura, Y.

    1994-01-01

    The mi locus of mice encodes a novel member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (hereafter called mi factor). In addition to microphthalmus, osteopetrosis, and lack of melanocytes, mice of mi/mi genotype are deficient in mast cells. Since the c-kit receptor tyrosine kinase plays an important role in the development of mast cells, and since the c-kit expression by cultured mast cells from mi/mi mice is deficient in both mRNA and protein levels, the mast cell deficiency of mi/mi mice has been attributed at least in part to the deficient expression of c-kit. However, it remained to be examined whether the c-kit expression was also deficient in tissues of mi/mi mice. In the present study, we examined the c-kit expression by mi/mi skin mast cells using in situ hybridization and immunohistochemistry. Moreover, we examined the c-kit expression by various cells other than mast cells in tissues of mi/mi mice. We found that the c-kit expression was deficient in mast cells but not in erythroid precursors, testicular germ cells, and neurons of mi/mi mice. This suggested that the regulation of the c-kit transcription by the mi factor was dependent on cell types. Mice of mi/mi genotype appeared to be a useful model to analyze the function of transcription factors in the whole-animal level. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7524330

  13. Regulation of an Autoimmune Model for Multiple Sclerosis in Th2-Biased GATA3 Transgenic Mice

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    Viromi Fernando

    2014-01-01

    Full Text Available T helper (Th2 cells have been proposed to play a neuroprotective role in multiple sclerosis (MS. This is mainly based on “loss-of-function” studies in an animal model for MS, experimental autoimmune encephalomyelitis (EAE, using blocking antibodies against Th2 related cytokines, and knockout mice lacking Th2-related molecules. We tested whether an increase of Th2 responses (“gain-of-function” approach could alter EAE, the approach of novel GATA binding protein 3 (GATA3-transgenic (tg mice that overexpress GATA3, a transcription factor required for Th2 differentiation. In EAE induced with myelin oligodendrocyte glycoprotein (MOG35−55 peptide, GATA3-tg mice had a significantly delayed onset of disease and a less severe maximum clinical score, compared with wild-type C57BL/6 mice. Histologically, GATA3-tg mice had decreased levels of meningitis and demyelination in the spinal cord, and anti-inflammatory cytokine profiles immunologically, however both groups developed similar levels of MOG-specific lymphoproliferative responses. During the early stage, we detected higher levels of interleukin (IL-4 and IL-10, with MOG and mitogen stimulation of regional lymph node cells in GATA3-tg mice. During the late stage, only mitogen stimulation induced higher IL-4 and lower interferon-γ and IL-17 production in GATA3-tg mice. These results suggest that a preexisting bias toward a Th2 immune response may reduce the severity of inflammatory demyelinating diseases, including MS.

  14. Frontal Lobe Contusion in Mice Chronically Impairs Prefrontal-Dependent Behavior.

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    Austin Chou

    Full Text Available Traumatic brain injury (TBI is a major cause of chronic disability in the world. Moderate to severe TBI often results in damage to the frontal lobe region and leads to cognitive, emotional, and social behavioral sequelae that negatively affect quality of life. More specifically, TBI patients often develop persistent deficits in social behavior, anxiety, and executive functions such as attention, mental flexibility, and task switching. These deficits are intrinsically associated with prefrontal cortex (PFC functionality. Currently, there is a lack of analogous, behaviorally characterized TBI models for investigating frontal lobe injuries despite the prevalence of focal contusions to the frontal lobe in TBI patients. We used the controlled cortical impact (CCI model in mice to generate a frontal lobe contusion and studied behavioral changes associated with PFC function. We found that unilateral frontal lobe contusion in mice produced long-term impairments to social recognition and reversal learning while having only a minor effect on anxiety and completely sparing rule shifting and hippocampal-dependent behavior.

  15. The Cstf2t Polyadenylation Gene Plays a Sex-Specific Role in Learning Behaviors in Mice.

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    Jaryse C Harris

    Full Text Available Polyadenylation is an essential mechanism for the processing of mRNA 3' ends. CstF-64 (the 64,000 Mr subunit of the cleavage stimulation factor; gene symbol Cstf2 is an RNA-binding protein that regulates mRNA polyadenylation site usage. We discovered a paralogous form of CstF-64 called τCstF-64 (Cstf2t. The Cstf2t gene is conserved in all eutherian mammals including mice and humans, but the τCstF-64 protein is expressed only in a subset of mammalian tissues, mostly testis and brain. Male mice that lack Cstf2t (Cstf2t-/- mice experience disruption of spermatogenesis and are infertile, although female fertility is unaffected. However, a role for τCstF-64 in the brain has not yet been determined. Given the importance of RNA polyadenylation and splicing in neuronal gene expression, we chose to test the hypothesis that τCstF-64 is important for brain function. Male and female 185-day old wild type and Cstf2t-/- mice were examined for motor function, general activity, learning, and memory using rotarod, open field activity, 8-arm radial arm maze, and Morris water maze tasks. Male wild type and Cstf2t-/- mice did not show differences in learning and memory. However, female Cstf2t-/- mice showed significantly better retention of learned maze tasks than did female wild type mice. These results suggest that τCstf-64 is important in memory function in female mice. Interestingly, male Cstf2t-/- mice displayed less thigmotactic behavior than did wild type mice, suggesting that Cstf2t may play a role in anxiety in males. Taken together, our studies highlight the importance of mRNA processing in cognition and behavior as well as their established functions in reproduction.

  16. Low transformation growth factor-β1 production and collagen synthesis correlate with the lack of hepatic periportal fibrosis development in undernourished mice infected with Schistosoma mansoni

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    Andreia Ferreira Barros

    2014-04-01

    Full Text Available Undernourished mice infected (UI submitted to low and long-lasting infections by Schistosoma mansoni are unable to develop the hepatic periportal fibrosis that is equivalent to Symmers’ fibrosis in humans. In this report, the effects of the host’s nutritional status on parasite (worm load, egg viability and maturation and host (growth curves, biology, collagen synthesis and characteristics of the immunological response were studied and these are considered as interdependent factors influencing the amount and distribution of fibrous tissue in hepatic periovular granulomas and portal spaces. The nutritional status of the host influenced the low body weight and low parasite burden detected in UI mice as well as the number, viability and maturation of released eggs. The reduced oviposition and increased number of degenerated or dead eggs were associated with low protein synthesis detected in deficient hosts, which likely induced the observed decrease in transformation growth factor (TGF-β1 and liver collagen. Despite the reduced number of mature eggs in UI mice, the activation of TGF-β1 and hepatic stellate cells occurred regardless of the unviability of most miracidia, due to stimulation by fibrogenic proteins and eggshell glycoproteins. However, changes in the repair mechanisms influenced by the nutritional status in deficient animals may account for the decreased liver collagen detected in the present study.

  17. Live attenuated S. Typhimurium vaccine with improved safety in immuno-compromised mice.

    Directory of Open Access Journals (Sweden)

    Balamurugan Periaswamy

    Full Text Available Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV. Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb(-/-nos2(-/- animals lacking NADPH oxidase and inducible NO synthase. In cybb(-/-nos2(-/- mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093, was >1000-fold attenuated in cybb(-/-nos2(-/- mice and ≈100 fold attenuated in tnfr1(-/- animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.

  18. An Essential Physiological Role for MCT8 in Bone in Male Mice.

    Science.gov (United States)

    Leitch, Victoria D; Di Cosmo, Caterina; Liao, Xiao-Hui; O'Boy, Sam; Galliford, Thomas M; Evans, Holly; Croucher, Peter I; Boyde, Alan; Dumitrescu, Alexandra; Weiss, Roy E; Refetoff, Samuel; Williams, Graham R; Bassett, J H Duncan

    2017-09-01

    T3 is an important regulator of skeletal development and adult bone maintenance. Thyroid hormone action requires efficient transport of T4 and T3 into target cells. We hypothesized that monocarboxylate transporter (MCT) 8, encoded by Mct8 on the X-chromosome, is an essential thyroid hormone transporter in bone. To test this hypothesis, we determined the juvenile and adult skeletal phenotypes of male Mct8 knockout mice (Mct8KO) and Mct8D1D2KO compound mutants, which additionally lack the ability to convert the prohormone T4 to the active hormone T3. Prenatal skeletal development was normal in both Mct8KO and Mct8D1D2KO mice, whereas postnatal endochondral ossification and linear growth were delayed in both Mct8KO and Mct8D1D2KO mice. Furthermore, bone mass and mineralization were decreased in adult Mct8KO and Mct8D1D2KO mice, and compound mutants also had reduced bone strength. Delayed bone development and maturation in Mct8KO and Mct8D1D2KO mice is consistent with decreased thyroid hormone action in growth plate chondrocytes despite elevated serum T3 concentrations, whereas low bone mass and osteoporosis reflects increased thyroid hormone action in adult bone due to elevated systemic T3 levels. These studies identify an essential physiological requirement for MCT8 in chondrocytes, and demonstrate a role for additional transporters in other skeletal cells during adult bone maintenance.

  19. Impaired Sperm Maturation in Rnase9 Knockout Mice1

    Science.gov (United States)

    Westmuckett, Andrew D.; Nguyen, Edward B.; Herlea-Pana, Oana M.; Alvau, Antonio; Salicioni, Ana M.; Moore, Kevin L.

    2014-01-01

    ABSTRACT Ribonuclease, RNase A family, 9 (RNASE9) is a ribonuclease A superfamily member that is expressed only in the epididymis. It is a small, secreted polypeptide, it lacks ribonuclease activity, and its function(s) is unknown. However, epididymis-specific expression suggests a role in sperm maturation. We generated Rnase9−/− mice to study RNASE9 function in vivo. We confirm that RNASE9 expression is restricted to the epididymis. Within the epididymis, RNASE9 is first detected in midcaput, persists through the distal caput and corpus, and wanes in the cauda. Rnase9−/− mice are born at the expected Mendelian ratio, have normal postnatal growth and development, and have no outwardly apparent phenotype. Spermatogenesis is normal, and Rnase9-null sperm are morphologically normal. Rnase9−/− males have normal fertility in unrestricted mating trials, and fertilization rates in in vitro fertilization assays are indistinguishable from wild-type mice. Visual observations coupled with analyses of sperm velocities shortly after swim out from the corpus shows that motility of Rnase9-null sperm is significantly impaired. However, no differences between wild-type and Rnase9-null sperm are detected by computer-assisted sperm analysis 10–90 min after sperm isolation from the corpus or cauda. Assessment of capacitation-dependent signaling pathways in Rnase9-null sperm showed that, while levels of tyrosine phosphorylation of sperm proteins were normal, there was decreased phosphorylation of protein kinase A substrates upon capacitation compared to wild-type mice. In conclusion, RNASE9 is dispensable for fertility, but the absence of RNASE9 during epididymal transit results in impaired sperm maturation. PMID:24719258

  20. Nuclear factor erythroid 2-related factor 2 deletion impairs glucose tolerance and exacerbates hyperglycemia in type 1 diabetic mice.

    Science.gov (United States)

    Aleksunes, Lauren M; Reisman, Scott A; Yeager, Ronnie L; Goedken, Michael J; Klaassen, Curtis D

    2010-04-01

    The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) induces a battery of cytoprotective genes after oxidative stress. Nrf2 aids in liver regeneration by altering insulin signaling; however, whether Nrf2 participates in hepatic glucose homeostasis is unknown. Compared with wild-type mice, mice lacking Nrf2 (Nrf2-null) have lower basal serum insulin and prolonged hyperglycemia in response to an intraperitoneal glucose challenge. In the present study, blood glucose, serum insulin, urine flow rate, and hepatic expression of glucose-related genes were quantified in male diabetic wild-type and Nrf2-null mice. Type 1 diabetes was induced with a single intraperitoneal dose (200 mg/kg) of streptozotocin (STZ). Histopathology and serum insulin levels confirmed depleted pancreatic beta-cells in STZ-treated mice of both genotypes. Five days after STZ, Nrf2-null mice had higher blood glucose levels than wild-type mice. Nine days after STZ, polyuria occurred in both genotypes with more urine output from Nrf2-null mice (11-fold) than wild-type mice (7-fold). Moreover, STZ-treated Nrf2-null mice had higher levels of serum beta-hydroxybutyrate, triglycerides, and fatty acids 10 days after STZ compared with wild-type mice. STZ reduced hepatic glycogen in both genotypes, with less observed in Nrf2-null mice. Increased urine output and blood glucose in STZ-treated Nrf2-null mice corresponded with enhanced gluconeogenesis (glucose-6-phosphatase and phosphoenolpyruvate carboxykinase)- and reduced glycolysis (pyruvate kinase)-related mRNA expression in their livers. Furthermore, the Nrf2 activator oltipraz lowered blood glucose in wild-type but not Nrf2-null mice administered STZ. Collectively, these data indicate that the absence of Nrf2 worsens hyperglycemia in type I diabetic mice and Nrf2 may represent a therapeutic target for reducing circulating glucose levels.

  1. Establishment of Demodex canis on canine skin engrafted onto scid-beige mice.

    Science.gov (United States)

    Caswell, J L; Yager, J A; Barta, J R; Parker, W

    1996-12-01

    A small animal model of canine demodicosis is described. Normal canine skin was engrafted onto scid (severe combined immunodeficient)-beige mice, which lack functional B and T lymphocytes and have reduced natural killer cell activity. The xenografts were later infected with Demodex canis collected from a dog with demodicosis. At 30-112 days following infection, mites were seen histologically in the canine hair follicles of the engrafted skin. Demodex canis adults, nymphs, larvae, and eggs were present in samples macerated in sodium hydroxide. Mite infestations could not be demonstrated in the mouse skin, nor were mites passed from the infected graft to uninfected skin grafts on in-contact mice. This model may be utilized to assess the efficacy of miticidal treatments, to evaluate the importance of specific components of the immune response, and to study the biology of D. canis.

  2. Folate and S-adenosylmethionine modulate synaptic activity in cultured cortical neurons: acute differential impact on normal and apolipoprotein-deficient mice

    International Nuclear Information System (INIS)

    Serra, Michael; Chan, Amy; Dubey, Maya; Shea, Thomas B; Gilman, Vladimir

    2008-01-01

    Folate deficiency is accompanied by a decline in the cognitive neurotransmitter acetylcholine and a decline in cognitive performance in mice lacking apolipoprotein E (ApoE−/− mice), a low-density lipoprotein that regulates aspects of lipid metabolism. One direct consequence of folate deficiency is a decline in S-adenosylmethionine (SAM). Since dietary SAM supplementation maintains acetylcholine levels and cognitive performance in the absence of folate, we examined herein the impact of folate and SAM on neuronal synaptic activity. Embryonic cortical neurons from mice expressing or lacking ApoE (ApoE+/+ or −/−, respectively) were cultured for 1 month on multi-electrode arrays, and signaling was recorded. ApoE+/+ cultures displayed significantly more frequent spontaneous signals than ApoE−/− cultures. Supplementation with 166 µm SAM (not normally present in culture medium) increased signal frequency and decreased signal amplitude in ApoE+/+ cultures. SAM also increased the frequency of tightly clustered signal bursts. Folate deprivation reversibly reduced signal frequency in ApoE+/+ cultures; SAM supplementation maintained signal frequency despite folate deprivation. These findings support the importance of dietary supplementation with folate and SAM on neuronal health. Supplementation with 166 µm SAM did not alter signaling in ApoE−/− cultures, which may be a reflection of the reduced SAM levels in ApoE−/− mice. The differential impact of SAM on ApoE+/+ and −/− neurons underscores the combined impact of nutritional and genetic deficiencies on neuronal homeostasis. (communication)

  3. Myosin heavy chain isoform expression in adult and juvenile mini-muscle mice bred for high-voluntary wheel running.

    Science.gov (United States)

    Talmadge, Robert J; Acosta, Wendy; Garland, Theodore

    2014-11-01

    The myosin heavy chain (MyHC) isoform composition of locomotor and non-locomotor muscles of mini-muscle mice were assessed at the protein and mRNA levels in both adult and juvenile (21 day old) mice. Mini-muscle mice are one outcome of a replicated artificial selection experiment in which four lines of mice were bred for high voluntary wheel running (HR lines). Two of the lines responded with an increase in frequency of a single nucleotide polymorphism in an intron in the MyHC-2b gene (myh4) that when homozygous causes a dramatic reduction in triceps surae mass. We found that both locomotor and non-locomotor muscles of adult mini-muscle mice displayed robust reductions, but not elimination, of the MyHC-2b isoform at both the protein and mRNA levels, with commensurate increases in MyHC-2x and sometimes MyHC-2a, as compared with either a line of HR mice that does not display the mini-muscle phenotype or inbred C57Bl6 mice. Immunohistochemical analyses revealed that locomotor muscles of mini-muscle mice contain fibers that express the MyHC-2b isoform, which migrates normally in SDS-PAGE gels. However, these MyHC-2b positive fibers are generally smaller than the surrounding fibers and smaller than the MyHC-2b positive fibers of non-mini-muscle mice, resulting in characteristically fast muscles that lack a substantial MyHC-2b positive (superficial) region. In contrast, the masseter, a non-locomotor muscle of mini-muscle mice contained MyHC-2b positive fibers that stained more lightly for MyHC-2b, but appeared normal in size and distribution. In adults, many of the MyHC-2b positive fibers in the mini-muscle mice also display central nuclei. Only a small proportion of small MyHC-2b fibers in mini-muscle mice stained positive for the neural cell adhesion molecule, suggesting that anatomical innervation was not compromised. In addition, weanling (21 day old), but not 5 day old mice, displayed alterations in MyHC isoform content at both the protein and mRNA levels, including

  4. AKAP13 Rho-GEF and PKD-binding domain deficient mice develop normally but have an abnormal response to β-adrenergic-induced cardiac hypertrophy.

    Directory of Open Access Journals (Sweden)

    Matthew J Spindler

    Full Text Available A-kinase anchoring proteins (AKAPs are scaffolding molecules that coordinate and integrate G-protein signaling events to regulate development, physiology, and disease. One family member, AKAP13, encodes for multiple protein isoforms that contain binding sites for protein kinase A (PKA and D (PKD and an active Rho-guanine nucleotide exchange factor (Rho-GEF domain. In mice, AKAP13 is required for development as null embryos die by embryonic day 10.5 with cardiovascular phenotypes. Additionally, the AKAP13 Rho-GEF and PKD-binding domains mediate cardiomyocyte hypertrophy in cell culture. However, the requirements for the Rho-GEF and PKD-binding domains during development and cardiac hypertrophy are unknown.To determine if these AKAP13 protein domains are required for development, we used gene-trap events to create mutant mice that lacked the Rho-GEF and/or the protein kinase D-binding domains. Surprisingly, heterozygous matings produced mutant mice at Mendelian ratios that had normal viability and fertility. The adult mutant mice also had normal cardiac structure and electrocardiograms. To determine the role of these domains during β-adrenergic-induced cardiac hypertrophy, we stressed the mice with isoproterenol. We found that heart size was increased similarly in mice lacking the Rho-GEF and PKD-binding domains and wild-type controls. However, the mutant hearts had abnormal cardiac contractility as measured by fractional shortening and ejection fraction.These results indicate that the Rho-GEF and PKD-binding domains of AKAP13 are not required for mouse development, normal cardiac architecture, or β-adrenergic-induced cardiac hypertrophic remodeling. However, these domains regulate aspects of β-adrenergic-induced cardiac hypertrophy.

  5. Anxiolytic effects of orcinol glucoside and orcinol monohydrate in mice.

    Science.gov (United States)

    Wang, Xiaohong; Li, Guiyun; Li, Peng; Huang, Linyuan; Huang, Jianmei; Zhai, Haifeng

    2015-06-01

    Anxiety is a common psychological disorder, often occurring in combination with depression, but therapeutic drugs with high efficacy and safety are lacking. Orcinol glucoside (OG) was recently found to have an antidepressive action. To study the therapeutic potential of OG and orcinol monohydrate (OM) as anxiolytic agents. Anxiolytic effects in mice were measured using the elevated plus-maze, hole-board, and open-field tests. Eight groups of mice were included in each test. Thirty minutes before each test, mice in each group received one oral administration of OG (5, 10, or 20 mg/kg), OM (2.5, 5, or 10 mg/kg), the positive control diazepam (1 or 5 mg/kg), or control vehicle. Each mouse underwent only one test. Uptake of orcinol (5 mg/kg) in the brain was qualitatively detected using the HPLC-MS method. OG (5, 10, and 20 mg/kg) and OM (2.5 and 5 mg/kg) increased the time spent in open arms and the number of entries into open arms in the elevated plus-maze test. OG (5 and 10 mg/kg) and OM (2.5 and 5 mg/kg) increased the number of head-dips in the hole-board test. At all tested doses, OG and OM did not significantly affect the locomotion of mice in the open-field test. Orcinol could be detected in the mouse brain homogenates 30 min after oral OM administration, having confirmed that OM is centrally active. The results demonstrated that OG and OM are anxiolytic agents without sedative effects, indicating their therapeutic potential for anxiety.

  6. Otitis media induced by peptidoglycan-polysaccharide (PGPS) in TLR2-deficient (Tlr2(-/-)) mice for developing drug therapy.

    Science.gov (United States)

    Zhang, Xiaolin; Zheng, Tihua; Sang, Lu; Apisa, Luke; Zhao, Hongchun; Fu, Fenghua; Wang, Qingzhu; Wang, Yanfei; Zheng, Qingyin

    2015-10-01

    Toll like receptor 2 (TLR2) signaling can regulate the pathogenesis of otitis media (OM). However, the precise role of TLR2 signaling in OM has not been clarified due to the lack of an optimal animal model. Peptidoglycan-polysaccharide (PGPS) of the bacterial cell wall can induce inflammation by activating the TLR2 signaling. This study aimed at examining the pathogenic characteristics of OM induced by PGPS in Tlr2(-/-) mice, and the potential therapeutic effect of sodium aescinate (SA) in this model. Wild-type (WT) and Tlr2(-/-) mice were inoculated with streptococcal PGPS into their middle ears (MEs) and treated intravenously with vehicle or SA daily beginning at 3days prior to PGPS for 6 consecutive days. The pathologic changes of individual mice were evaluated longitudinally. In comparison with WT mice, Tlr2(-/-) mice were susceptible to PGPS-induced OM. Tlr2(-/-) mice displayed greater hearing loss, tympanic membrane damage, ME mucosal thickening, longer inflammation state, cilia and goblet cell loss. SA-treatment decreased neutrophil infiltration, modulated TLR2-related gene expression and improved ciliary organization. PGPS induced a relatively stable OM in Tlr2(-/-) mice, providing a new model for OM research. Treatment with SA mitigated the pathogenic damage in the ME and may be valuable for intervention of OM. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Uncovering the mystery of opposite circadian rhythms between mouse and human leukocytes in humanized mice.

    Science.gov (United States)

    Zhao, Yue; Liu, Min; Chan, Xue Ying; Tan, Sue Yee; Subramaniam, Sharrada; Fan, Yong; Loh, Eva; Chang, Kenneth Tou En; Tan, Thiam Chye; Chen, Qingfeng

    2017-11-02

    Many immune parameters show circadian rhythms during the 24-hour day in mammals. The most striking circadian oscillation is the number of circulating immune cells that display an opposite rhythm between humans and mice. The physiological roles and mechanisms of circadian variations in mouse leukocytes are well studied, whereas for humans they remain unclear because of the lack of a proper model. In this study, we found that consistent with their natural host species, mouse and human circulating leukocytes exhibited opposite circadian oscillations in humanized mice. This cyclic pattern of trafficking correlated well with the diurnal expression levels of C-X-C chemokine receptor 4, which were controlled by the intracellular hypoxia-inducible factor 1α/aryl hydrocarbon receptor nuclear translocator-like heterodimer. Furthermore, we also discovered that p38 mitogen-activated protein kinases/mitogen-activated 2 had opposite effects between mice and humans in generating intracellular reactive oxygen species, which subsequently regulated HIF-1α expression. In conclusion, we propose humanized mice as a robust model for human circadian studies and reveal insights on a novel molecular clock network in the human circadian rhythm. © 2017 by The American Society of Hematology.

  8. Antiretroviral pre-exposure prophylaxis prevents vaginal transmission of HIV-1 in humanized BLT mice.

    Directory of Open Access Journals (Sweden)

    Paul W Denton

    2008-01-01

    Full Text Available Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.We show that the female reproductive tract of humanized bone marrow-liver-thymus (BLT mice is reconstituted with human CD4+ T and other relevant human cells, rendering these humanized mice susceptible to intravaginal infection by HIV-1. Effects of HIV-1 infection include CD4+ T cell depletion in gut-associated lymphoid tissue (GALT that closely mimics what is observed in HIV-1-infected humans. We also show that pre-exposure prophylaxis with antiretroviral drugs is a highly effective method for preventing vaginal HIV-1 transmission. Whereas 88% (7/8 of BLT mice inoculated vaginally with HIV-1 became infected, none of the animals (0/5 given pre-exposure prophylaxis of emtricitabine (FTC/tenofovir disoproxil fumarate (TDF showed evidence of infection (Chi square = 7.5, df = 1, p = 0.006.The fact that humanized BLT mice are susceptible to intravaginal infection makes this system an excellent candidate for preclinical evaluation of both microbicides and pre-exposure prophylactic regimens. The utility of humanized mice to study intravaginal HIV-1 transmission is particularly highlighted by the demonstration that pre-exposure prophylaxis can prevent intravaginal HIV-1 transmission in the BLT mouse model.

  9. Androgen Receptor (AR) Physiological Roles in Male and Female Reproductive Systems: Lessons Learned from AR-Knockout Mice Lacking AR in Selective Cells1

    Science.gov (United States)

    Chang, Chawnshang; Lee, Soo Ok; Wang, Ruey-Sheng; Yeh, Shuyuan; Chang, Ta-Min

    2013-01-01

    ABSTRACT Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases. PMID:23782840

  10. CD4(+) T cell-mediated control of a gamma-herpesvirus in B cell-deficient mice is mediated by IFN-gamma

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Cardin, R D; Branum, K C

    1999-01-01

    The lack of B cells and antibody does not prevent mice from dealing effectively with a pathogenic gamma-herpesvirus. Both CD4(+) and CD8(+) T cells contribute to the control of virus replication in the respiratory tract, with the depletion of either lymphocyte subset leading to increased titers...... for direct interaction with virus-infected targets expressing MHC class II glycoproteins, suggesting that the IFN-gamma produced by these lymphocytes is functioning at short range. The numbers of latently infected cells in the spleens of carrier mice are also significantly increased by the concurrent...

  11. Synaptic function is modulated by LRRK2 and glutamate release is increased in cortical neurons of G2019S LRRK2 knock-in mice.

    Science.gov (United States)

    Beccano-Kelly, Dayne A; Kuhlmann, Naila; Tatarnikov, Igor; Volta, Mattia; Munsie, Lise N; Chou, Patrick; Cao, Li-Ping; Han, Heather; Tapia, Lucia; Farrer, Matthew J; Milnerwood, Austen J

    2014-01-01

    Mutations in Leucine-Rich Repeat Kinase-2 (LRRK2) result in familial Parkinson's disease and the G2019S mutation alone accounts for up to 30% in some ethnicities. Despite this, the function of LRRK2 is largely undetermined although evidence suggests roles in phosphorylation, protein interactions, autophagy and endocytosis. Emerging reports link loss of LRRK2 to altered synaptic transmission, but the effects of the G2019S mutation upon synaptic release in mammalian neurons are unknown. To assess wild type and mutant LRRK2 in established neuronal networks, we conducted immunocytochemical, electrophysiological and biochemical characterization of >3 week old cortical cultures of LRRK2 knock-out, wild-type overexpressing and G2019S knock-in mice. Synaptic release and synapse numbers were grossly normal in LRRK2 knock-out cells, but discretely reduced glutamatergic activity and reduced synaptic protein levels were observed. Conversely, synapse density was modestly but significantly increased in wild-type LRRK2 overexpressing cultures although event frequency was not. In knock-in cultures, glutamate release was markedly elevated, in the absence of any change to synapse density, indicating that physiological levels of G2019S LRRK2 elevate probability of release. Several pre-synaptic regulatory proteins shown by others to interact with LRRK2 were expressed at normal levels in knock-in cultures; however, synapsin 1 phosphorylation was significantly reduced. Thus, perturbations to the pre-synaptic release machinery and elevated synaptic transmission are early neuronal effects of LRRK2 G2019S. Furthermore, the comparison of knock-in and overexpressing cultures suggests that one copy of the G2019S mutation has a more pronounced effect than an ~3-fold increase in LRRK2 protein. Mutant-induced increases in transmission may convey additional stressors to neuronal physiology that may eventually contribute to the pathogenesis of Parkinson's disease.

  12. Selective chemokine receptor usage by central nervous system myeloid cells in CCR2-red fluorescent protein knock-in mice.

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    Noah Saederup

    2010-10-01

    Full Text Available Monocyte subpopulations distinguished by differential expression of chemokine receptors CCR2 and CX3CR1 are difficult to track in vivo, partly due to lack of CCR2 reagents.We created CCR2-red fluorescent protein (RFP knock-in mice and crossed them with CX3CR1-GFP mice to investigate monocyte subset trafficking. In mice with experimental autoimmune encephalomyelitis, CCR2 was critical for efficient intrathecal accumulation and localization of Ly6C(hi/CCR2(hi monocytes. Surprisingly, neutrophils, not Ly6C(lo monocytes, largely replaced Ly6C(hi cells in the central nervous system of these mice. CCR2-RFP expression allowed the first unequivocal distinction between infiltrating monocytes/macrophages from resident microglia.These results refine the concept of monocyte subsets, provide mechanistic insight about monocyte entry into the central nervous system, and present a novel model for imaging and quantifying inflammatory myeloid populations.

  13. Not all mice are equal: welfare implications of behavioural habituation profiles in four 129 mouse substrains.

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    Hetty Boleij

    Full Text Available Safeguarding the welfare of animals is an important aim when defining housing and management standards in animal based, experimental research. While such standards are usually defined per animal species, it is known that considerable differences between laboratory mouse strains exist, for example with regard to their emotional traits. Following earlier experiments, in which we found that 129P3 mice show a lack of habituation of anxiety related behaviour after repeated exposure to an initially novel environment (non-adaptive profile, we here investigated four other 129 inbred mouse substrains (129S2/SvPas, 129S2/SvHsd (exp 1; 129P2 and 129X1 (exp 2 on habituation of anxiety related behaviour. Male mice of each strain were repeatedly placed in the modified hole board test, measuring anxiety-related behaviour, exploratory and locomotor behaviour. The results reveal that all four substrains show a lack of habituation behaviour throughout the period of testing. Although not in all of the substrains a possible confounding effect of general activity can be excluded, our findings suggest that the genetic background of the 129 substrains may increase their vulnerability to cope with environmental challenges, such as exposure to novelty. This vulnerability might negatively affect the welfare of these mice under standard laboratory conditions when compared with other strains. Based on our findings we suggest to consider (substrain-specific guidelines and protocols, taking the (substrain-specific adaptive capabilities into account.

  14. Acquiring, recording, and analyzing pathology data from experimental mice: an overview.

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    Scudamore, Cheryl L

    2014-03-21

    Pathology is often underutilized as an end point in mouse studies in academic research because of a lack of experience and expertise. The use of traditional pathology techniques including necropsy and microscopic analysis can be useful in identifying the basic processes underlying a phenotype and facilitating comparison with equivalent human diseases. This overview aims to provide a guide and reference to the acquisition, recording, and analysis of high-quality pathology data from experimental mice in an academic research setting. Copyright © 2014 John Wiley & Sons, Inc.

  15. Differential regulation of morphine antinociceptive effects by endogenous enkephalinergic system in the forebrain of mice

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    Sun Wei-Zen

    2008-09-01

    Full Text Available Abstract Background Mice lacking the preproenkephalin (ppENK gene are hyperalgesic and show more anxiety and aggression than wild-type (WT mice. The marked behavioral changes in ppENK knock-out (KO mice appeared to occur in supraspinal response to painful stimuli. However the functional role of enkephalins in the supraspinal nociceptive processing and their underlying mechanism is not clear. The aim of present study was to compare supraspinal nociceptive and morphine antinociceptive responses between WT and ppENK KO mice. Results The genotypes of bred KO mice were confirmed by PCR. Met-enkephalin immunoreactive neurons were labeled in the caudate-putamen, intermediated part of lateral septum, lateral globus pallidus, intermediated part of lateral septum, hypothalamus, and amygdala of WT mice. Met-enkephalin immunoreactive neurons were not found in the same brain areas in KO mice. Tail withdrawal and von Frey test results did not differ between WT and KO mice. KO mice had shorter latency to start paw licking than WT mice in the hot plate test. The maximal percent effect of morphine treatments (5 mg/kg and 10 mg/kg, i.p. differed between WT and KO mice in hot plate test. The current source density (CSD profiles evoked by peripheral noxious stimuli in the primary somatosenstory cortex (S1 and anterior cingulate cortex (ACC were similar in WT and KO mice. After morphine injection, the amplitude of the laser-evoked sink currents was decreased in S1 while the amplitude of electrical-evoked sink currents was increased in the ACC. These differential morphine effects in S1 and ACC were enhanced in KO mice. Facilitation of synaptic currents in the ACC is mediated by GABA inhibitory interneurons in the local circuitry. Percent increases in opioid receptor binding in S1 and ACC were 5.1% and 5.8%, respectively. Conclusion The present results indicate that the endogenous enkephalin system is not involved in acute nociceptive transmission in the spinal cord

  16. A map of brain neuropils and fiber systems in the ant Cardiocondyla obscurior

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    Joris eBressan

    2015-02-01

    Full Text Available A wide spectrum of occupied ecological niches and spectacular morphological adaptations make social insects a prime object for comparative neuroanatomical studies. Eusocial insects have evolved complex societies based on caste polyphenism. A diverse behavioral repertoire of morphologically distinct castes of the same species requires a high degree of plasticity in the central nervous system. We have analyzed the central brain neuropils and fiber tract systems of the worker of the ant Cardiocondyla obscurior, a model for the study of social traits. Our analysis is based on whole mount preparations of adult brains labeled with an antibody against Drosophila-Synapsin, which cross-reacts strongly with synapses in Cardiocondyla. Neuropil compartments stand out as domains with a certain texture and intensity of the anti-Synapsin signal. By contrast, fiber tracts, which are composed of bundles of axons accompanied by glia and are devoid of synapses, appear as channels or sheaths with low anti-Synapsin signal. We have generated a digital 3D atlas of the Cardiocondyla brain neuropil. The atlas provides a reference for future studies of brain polymorphisms in distinct castes, brain development or localization of neurotransmitter systems.

  17. A map of brain neuropils and fiber systems in the ant Cardiocondyla obscurior.

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    Bressan, Joris M A; Benz, Martin; Oettler, Jan; Heinze, Jürgen; Hartenstein, Volker; Sprecher, Simon G

    2014-01-01

    A wide spectrum of occupied ecological niches and spectacular morphological adaptations make social insects a prime object for comparative neuroanatomical studies. Eusocial insects have evolved complex societies based on caste polyphenism. A diverse behavioral repertoire of morphologically distinct castes of the same species requires a high degree of plasticity in the central nervous system. We have analyzed the central brain neuropils and fiber tract systems of the worker of the ant Cardiocondyla obscurior, a model for the study of social traits. Our analysis is based on whole mount preparations of adult brains labeled with an antibody against Drosophila-Synapsin, which cross-reacts strongly with synapses in Cardiocondyla. Neuropil compartments stand out as domains with a certain texture and intensity of the anti-Synapsin signal. By contrast, fiber tracts, which are composed of bundles of axons accompanied by glia and are devoid of synapses, appear as channels or sheaths with low anti-Synapsin signal. We have generated a digital 3D atlas of the Cardiocondyla brain neuropil. The atlas provides a reference for future studies of brain polymorphisms in distinct castes, brain development or localization of neurotransmitter systems.

  18. Hyperactivity and lack of social discrimination in the adolescent Fmr1 knockout mouse.

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    Sørensen, Emilie M; Bertelsen, Freja; Weikop, Pia; Skovborg, Maria M; Banke, Tue; Drasbek, Kim R; Scheel-Krüger, Jørgen

    2015-12-01

    The aims of this study were to investigate behaviour relevant to human autism spectrum disorder (ASD) and the fragile X syndrome in adolescent Fmr1 knockout (KO) mice and to evaluate the tissue levels of striatal monoamines. Fmr1 KO mice were evaluated in the open field, marble burying and three-chamber test for the presence of hyperactivity, anxiety, repetitive behaviour, sociability and observation of social novelty compared with wild-type (WT) mice. The Fmr1 KO mice expressed anxiety and hyperactivity in the open field compared with WT mice. This increased level of hyperactivity was confirmed in the three-chamber test. Fmr1 KO mice spent more time with stranger mice compared with the WT. However, after a correction for hyperactivity, their apparent increase in sociability became identical to that of the WT. Furthermore, the Fmr1 KO mice could not differentiate between a familiar or a novel mouse. Monoamines were measured by HPLC: Fmr1 KO mice showed an increase in the striatal dopamine level. We conclude that the fragile X syndrome model seems to be useful for understanding certain aspects of ASD and may have translational interest for studies of social behaviour when hyperactivity coexists in ASD patients.

  19. Lack of TAK1 in dendritic cells inhibits the contact hypersensitivity response induced by trichloroethylene in local lymph node assay

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    Yao, Pan; Hongqian, Chu; Qinghe, Meng; Lanqin, Shang; Jianjun, Jiang; Xiaohua, Yang; Xuetao, Wei; Weidong, Hao, E-mail: whao@bjmu.edu.cn

    2016-09-15

    Trichloroethylene (TCE) is a ubiquitous environmental contaminant. Occupational TCE exposure has been associated with severe, generalized contact hypersensitivity (CHS) skin disorder. The development of CHS depends on innate and adaptive immune functions. Transforming growth factor-β activated kinase-1 (TAK1) controls the survival of dendritic cells (DCs) that affect the immune system homeostasis. We aimed to investigate the role of TAK1 activity in DC on TCE-induced CHS response. Control mice and DC-specific TAK1 deletion mice were treated with 80% (v/v) TCE using local lymph node assay (LLNA) to establish a TCE-induced CHS model. The draining lymph nodes (DLNs) were excised and the lymphocytes were measure for proliferation by BrdU-ELISA, T-cell phenotype analysis by flow cytometry and signaling pathway activation by western blot. The ears were harvested for histopathological analysis. Control mice in the 80% TCE group displayed an inflammatory response in the ears, increased lymphocyte proliferation, elevated regulatory T-cell and activated T-cell percentages, and more IFN-γ producing CD8{sup +} T cells in DLNs. In contrast to control mice, DC-specific TAK1 deletion mice in the 80% TCE group showed an abolished CHS response and this was associated with defective T-cell expansion, activation and IFN-γ production. This effect may occur through Jnk and NF-κB signaling pathways. Overall, this study demonstrates a pivotal role of TAK1 in DCs in controlling TCE-induced CHS response and suggests that targeting TAK1 function in DCs may be a viable approach to preventing and treating TCE-related occupational health hazards. - Highlights: • Lack of TAK1 in DC caused an abolished TCE-induced CHS response. • TAK1 in DCs was essential to maintain the homeostasis of T cells in TCE-induced CHS. • Intact TAK1 in DCs was critical to promote T-cell priming in TCE-induced CHS. • DC-specific TAK1 deficiency abolished the TCE-mediated phosphorylation of Jnk.

  20. Lack of TAK1 in dendritic cells inhibits the contact hypersensitivity response induced by trichloroethylene in local lymph node assay

    International Nuclear Information System (INIS)

    Yao, Pan; Hongqian, Chu; Qinghe, Meng; Lanqin, Shang; Jianjun, Jiang; Xiaohua, Yang; Xuetao, Wei; Weidong, Hao

    2016-01-01

    Trichloroethylene (TCE) is a ubiquitous environmental contaminant. Occupational TCE exposure has been associated with severe, generalized contact hypersensitivity (CHS) skin disorder. The development of CHS depends on innate and adaptive immune functions. Transforming growth factor-β activated kinase-1 (TAK1) controls the survival of dendritic cells (DCs) that affect the immune system homeostasis. We aimed to investigate the role of TAK1 activity in DC on TCE-induced CHS response. Control mice and DC-specific TAK1 deletion mice were treated with 80% (v/v) TCE using local lymph node assay (LLNA) to establish a TCE-induced CHS model. The draining lymph nodes (DLNs) were excised and the lymphocytes were measure for proliferation by BrdU-ELISA, T-cell phenotype analysis by flow cytometry and signaling pathway activation by western blot. The ears were harvested for histopathological analysis. Control mice in the 80% TCE group displayed an inflammatory response in the ears, increased lymphocyte proliferation, elevated regulatory T-cell and activated T-cell percentages, and more IFN-γ producing CD8 + T cells in DLNs. In contrast to control mice, DC-specific TAK1 deletion mice in the 80% TCE group showed an abolished CHS response and this was associated with defective T-cell expansion, activation and IFN-γ production. This effect may occur through Jnk and NF-κB signaling pathways. Overall, this study demonstrates a pivotal role of TAK1 in DCs in controlling TCE-induced CHS response and suggests that targeting TAK1 function in DCs may be a viable approach to preventing and treating TCE-related occupational health hazards. - Highlights: • Lack of TAK1 in DC caused an abolished TCE-induced CHS response. • TAK1 in DCs was essential to maintain the homeostasis of T cells in TCE-induced CHS. • Intact TAK1 in DCs was critical to promote T-cell priming in TCE-induced CHS. • DC-specific TAK1 deficiency abolished the TCE-mediated phosphorylation of Jnk.