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Sample records for vesicular glutamate transporter-2

  1. Vesicular Glutamate Transporter 2 Expression in the Rat Pineal Gland: Detailed Analysis of Expression Pattern and Regulatory Mechanism

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    Yoshida, Sachine; Hisano, Setsuji

    Melatonin, a hormone secreted by the pineal gland, is closely related physiologically to circadian rhythm, sleep and reproduction, and also psychiatrically to mood disorders in humans. Under circadian control, melatonin secretion is modulated via nocturnal autonomic (adrenergic) stimulation to the gland, which expresses vesicular glutamate transporter (VGLUT) 1, VGLUT2 and a VGLUT1 splice variant (VGLUT1v), glutamatergic markers. Expression of VGLUT2 gene and protein in the intact gland has been reported to exhibit a rhythmic change during a day. To study VGLUT2 expression is under adrenergic control, we here performed an in vitro experiment using dispersed pineal cells of rats. Stimulation of either β-adrenergic receptor or cAMP production to the pineal cells was shown to increase mRNA level of VGLUT2, but not VGLUT1 and VGLUT1v. Because an ability of glutamate to inhibit melatonin production was previously reported in the cultured gland, it is likely that pineal VGLUT2 transports glutamate engaged in the inhibition of melatonin production.

  2. Patchy distributions of myelin and vesicular glutamate transporter 2 align with cytochrome oxidase blobs and interblobs in the superficial layers of the primary visual cortex

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    Rockoff, Emily C; Balaram, Pooja; Kaas, Jon H

    2014-01-01

    Blobs are a modular component of the primary visual cortex (area 17) of all primates, but not of other mammals closely related to primates. They are characterized as an even distribution of patches, puffs, or blobs of dense cytochrome oxidase (CO) expression in layer III of area 17, and are now known to differ from surrounding, nonblob cortex in thalamic, intrinsic, and extrastriate connections. Previous studies have also recognized a blob-like pattern of myelin-dense patches in layer III of area 17 of primates, and more recently the vesicular glutamate transporter (VGLUT)-2 isoform of the VGLUT family has been found to selectively distribute to layer III patches in a similar blob-like pattern. Here, we sought to determine if the blob-like patterns all identify the same modular structures in area 17 of primates by staining alternate brain sections cut parallel to the surface of area 17 of a prosimian primate (Otolemur garnettii) for CO, myelin, and VGLUT2. By aligning the sections from the three preparations, we provide clear evidence that the three preparations all identify the same modular blob structures. The results provide a further understanding of the functional nature of the blobs by demonstrating that their higher level of CO activity is related to thalamic inputs from the lateral geniculate nucleus that use VGLUT2 as their main glutamate transporter, and via myelinated axons. PMID:26097384

  3. Patchy distributions of myelin and vesicular glutamate transporter 2 align with cytochrome oxidase blobs and interblobs in the superficial layers of the primary visual cortex

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    Rockoff EC

    2014-09-01

    Full Text Available Emily C Rockoff,1 Pooja Balaram,1 Jon H Kaas1,2 1Department of Psychology, 2Department of Cell and Molecular Biology, Vanderbilt University, Nashville, TN, USA Abstract: Blobs are a modular component of the primary visual cortex (area 17 of all primates, but not of other mammals closely related to primates. They are characterized as an even distribution of patches, puffs, or blobs of dense cytochrome oxidase (CO expression in layer III of area 17, and are now known to differ from surrounding, nonblob cortex in thalamic, intrinsic, and extrastriate connections. Previous studies have also recognized a blob-like pattern of myelin-dense patches in layer III of area 17 of primates, and more recently the vesicular glutamate transporter (VGLUT-2 isoform of the VGLUT family has been found to selectively distribute to layer III patches in a similar blob-like pattern. Here, we sought to determine if the blob-like patterns all identify the same modular structures in area 17 of primates by staining alternate brain sections cut parallel to the surface of area 17 of a prosimian primate (Otolemur garnettii for CO, myelin, and VGLUT2. By aligning the sections from the three preparations, we provide clear evidence that the three preparations all identify the same modular blob structures. The results provide a further understanding of the functional nature of the blobs by demonstrating that their higher level of CO activity is related to thalamic inputs from the lateral geniculate nucleus that use VGLUT2 as their main glutamate transporter, and via myelinated axons. Keywords: columns, modules, visual cortex, primates, prosimians

  4. Vesicular glutamate transporter 2 (VGLUT2) is co-stored with PACAP in projections from the rat melanopsin-containing retinal ganglion cells

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    Engelund, Anna Iversen; Fahrenkrug, Jan; Harrison, Adrian Paul

    2010-01-01

    The retinal ganglion cell layer of the eye comprises a subtype of cells characterized by their intrinsic photosensitivity and expression of melanopsin (ipRGCs). These cells regulate a variety of non-image-forming (NIF) functions such as light entrainment of circadian rhythms, acute suppression......-localized in their projections in the suprachiasmatic nucleus, the intergeniculate leaflet, and the olivary pretectal nucleus. We conclude that there is evidence to support the use of glutamate and PACAP as neurotransmitters in NIF photoperception by rat ipRGCs, and that these neurotransmitters are co-stored and probably...

  5. Protons Regulate Vesicular Glutamate Transporters through an Allosteric Mechanism.

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    Eriksen, Jacob; Chang, Roger; McGregor, Matt; Silm, Katlin; Suzuki, Toshiharu; Edwards, Robert H

    2016-05-18

    The quantal nature of synaptic transmission requires a mechanism to transport neurotransmitter into synaptic vesicles without promoting non-vesicular efflux across the plasma membrane. Indeed, the vesicular transport of most classical transmitters involves a mechanism of H(+) exchange, which restricts flux to acidic membranes such as synaptic vesicles. However, vesicular transport of the principal excitatory transmitter glutamate depends primarily on membrane potential, which would drive non-vesicular efflux, and the role of protons is unclear. Adapting electrophysiology to record currents associated with the vesicular glutamate transporters (VGLUTs), we characterize a chloride conductance that is gated by lumenal protons and chloride and supports glutamate uptake. Rather than coupling stoichiometrically to glutamate flux, lumenal protons and chloride allosterically activate vesicular glutamate transport. Gating by protons serves to inhibit what would otherwise be substantial non-vesicular glutamate efflux at the plasma membrane, thereby restricting VGLUT activity to synaptic vesicles. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Molecular physiology of vesicular glutamate transporters in the digestive system

    Institute of Scientific and Technical Information of China (English)

    Tao Li; Fayez K. Ghishan; Liqun Bai

    2005-01-01

    Glutamate is the major excitatory neurotransmitter in the mammalian central nervous system (CNS). Packaging and storage of glutamate into glutamatergic neuronal vesicles require ATP-dependent vesicular glutamate uptake systems, which utilize the electrochemical proton gradient as a driving force. Three vesicular glutamate transporters (VGLUT1-3) have been recently identified from neuronal tissue where they play a key role to maintain the vesicular glutamate level. Recently, it has been demonstrated that glutamate signaling is also functional in peripheral neuronal and non-neuronal tissues, and occurs in sites of pituitary, adrenal, pineal glands, bone, GI tract, pancreas,skin, and testis. The glutamate receptors and VGLUTs in digestivesystem have been found in both neuronal and endocrinal cells. The glutamate signaling in the digestive system may have significant relevance to diabetes and GI tract motility disorders. This review will focus on the most recent update of molecular physiology of digestive VGLUTs.

  7. Distribution of vesicular glutamate transporters in the human brain

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    Erika eVigneault

    2015-03-01

    Full Text Available Glutamate is the major excitatory transmitter in the brain. Vesicular glutamate transporters (VGLUT1-3 are responsible for uploading glutamate into synaptic vesicles. VGLUT1 and VGLUT2 are considered as specific markers of canonical glutamatergic neurons, while VGLUT3 is found in neurons previously shown to use other neurotransmitters than glutamate. Although there exists a rich literature on the localization of these glutamatergic markers in the rodent brain, little is currently known about the distribution of VGLUT1-3 in the human brain. In the present study, using subtype specific probes and antisera, we examined the localization of the three vesicular glutamate transporters in the human brain by in situ hybridization, immunoautoradiography and immunohistochemistry. We found that the VGLUT1 transcript was highly expressed in the cerebral cortex, hippocampus and cerebellum, whereas VGLUT2 mRNA was mainly found in the thalamus and brainstem. VGLUT3 mRNA was localized in scarce neurons within the cerebral cortex, hippocampus, striatum and raphe nuclei. Following immunoautoradiographic labeling, intense VGLUT1- and VGLUT2-immunoreactivities were observed in all regions investigated (cerebral cortex, hippocampus, caudate-putamen, cerebellum, thalamus, amygdala, substantia nigra, raphe while VGLUT3 was absent from the thalamus and cerebellum. This extensive mapping of VGLUT1-3 in human brain reveals distributions that correspond for the most part to those previously described in rodent brains.

  8. Altered vesicular glutamate transporter expression in human temporal lobe epilepsy with hippocampal sclerosis

    NARCIS (Netherlands)

    Van Liefferinge, J.; Jensen, C.J.; Albertini, G.; Bentea, E.; Demuyser, T.; Merckx, E.; Aronica, E.; Smolders, I.; Massie, A.

    2015-01-01

    Vesicular glutamate transporters (VGLUTs) are responsible for loading glutamate into synaptic vesicles. Altered VGLUT protein expression has been suggested to affect quantal size and glutamate release under both physiological and pathological conditions. In this study, we investigated mRNA and

  9. Design, synthesis and biological evaluation of small-azo-dyes as potent Vesicular Glutamate Transporters inhibitors.

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    Favre-Besse, Franck-Cyril; Poirel, Odile; Bersot, Tiphaine; Kim-Grellier, Elodie; Daumas, Stephanie; El Mestikawy, Salah; Acher, Francine C; Pietrancosta, Nicolas

    2014-05-06

    Vesicular Glutamate Transporters (VGLUTs) allow the loading of presynapic glutamate vesicles and thus play a critical role in glutamatergic synaptic transmission. VGLUTs have proved to be involved in several major neuropathologies and directly correlated to clinical dementia in Alzheimer and Parkinson's disease. Accordingly VGLUT represent a key biological target or biomarker for neuropathology treatment or diagnostic. Yet, despite the pivotal role of VGLUTs, their pharmacology appears quite limited. Known competitive inhibitors are restricted to some dyes as Trypan Blue (TB) and glutamate mimics. This lack of pharmacological tools has heavily hampered VGLUT investigations. Here we report a rapid access to small molecules that combine benefits of TB and dicarboxylic quinolines (DCQs). Their ability to block vesicular glutamate uptake was evaluated. Several compounds displayed low micromolar inhibitory potency when size related compounds are thirty to forty times less potent (i.e. DCQ). We then confirmed the VGLUT selectivity by measuring the effect of the series on vesicular monoamine transport and on metabotropic glutamate receptor activity. These inhibitors are synthesized in only two steps and count among the best pharmacological tools for VGLUTs studies. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Preliminary evidence of apathetic-like behavior in aged vesicular monoamine transporter 2 deficient mice

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    Aron Baumann

    2016-11-01

    Full Text Available Apathy is considered to be a core feature of Parkinson’s disease (PD and has been associated with a variety of states and symptoms of the disease, such as increased severity of motor symptoms, impaired cognition, executive dysfunction, and dementia. Apart from the high prevalence of apathy in PD, which is estimated to be about 40%, the underlying pathophysiology remains poorly understood and current treatment approaches are unspecific and proved to be only partially effective. In animal models, apathy has been sub-optimally modeled, mostly by means of pharmacological and stress-induced methods, whereby concomitant depressive-like symptoms could not be ruled out. In the context of PD only a few studies on toxin-based models (i.e. 6-OHDA or MPTP claimed to have determined apathetic symptoms in animals. The assessment of apathetic symptoms in more elaborated and multifaceted genetic animal models of PD could help to understand the pathophysiological development of apathy in PD and eventually advance specific treatments for afflicted patients. Here we report the presence of behavioral signs of apathy in 12 months old mice that express only ~5% of the vesicular monoamine transporter 2 (VMAT2. Apathetic-like behavior in VMAT2 deficient (LO mice was evidenced by impaired burrowing and nest building skills, and a reduced preference for sweet solution in the saccharin preference test, while the performance in the forced swimming test was normal. Our preliminary results suggest that VMAT2 deficient mice show an apathetic-like phenotype that might be independent of depressive-like symptoms. Therefore VMAT2 LO mice could be a useful tool to study of the pathophysiological substrates of apathy and to test novel treatment strategies for apathy in the context of PD.

  11. Synaptic vesicles are capable of synthesizing the VGLUT substrate glutamate from α-ketoglutarate for vesicular loading.

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    Takeda, Kouji; Ishida, Atsuhiko; Takahashi, Kento; Ueda, Tetsufumi

    2012-04-01

    Synaptic vesicle loading of glutamate is a pivotal step in glutamate synaptic transmission. The molecular machinery responsible for this step is comprised of v-type proton-pump ATPase and a vesicular glutamate transporter. Recent evidence indicates that synaptic vesicles are endowed with glycolytic ATP-synthesizing enzymes, providing energy for immediate use by vesicle-bound proton-pump ATPase. In this study, we provide evidence that synaptic vesicles are also capable of synthesizing the vesicular glutamate transporter substrate glutamate, from α-ketoglutarate and l-aspartate (as the amino group donor); glutamate thus produced is taken up into vesicles. We also report a finding that α-ketoglutarate-derived glutamate uptake into synaptic vesicles and aspartate aminotransferase are inhibited by 2,3-pyrazinedicarboxylate. Evidence is given that this is a selective inhibitor for aspartate aminotransferase. These observations provide insight into understanding the nerve endings' mechanism for high efficiency in glutamate transmission. Finding this inhibitor may have implications for further experimentation on the role of α-ketoglutarate-derived glutamate in glutamate transmission. © 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry.

  12. Designing Novel Nanoformulations Targeting Glutamate Transporter Excitatory Amino Acid Transporter 2: Implications in Treating Drug Addiction.

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    Rao, Pss; Yallapu, Murali M; Sari, Youssef; Fisher, Paul B; Kumar, Santosh

    Chronic drug abuse is associated with elevated extracellular glutamate concentration in the brain reward regions. Deficit of glutamate clearance has been identified as a contributing factor that leads to enhanced glutamate concentration following extended drug abuse. Importantly, normalization of glutamate level through induction of glutamate transporter 1 (GLT1)/ excitatory amino acid transporter 2 (EAAT2) expression has been described in several in vivo studies. GLT1 upregulators including ceftriaxone, a beta-lactam antibiotic, have been effective in attenuating drug-seeking and drug-consumption behavior in rodent models. However, potential obstacles toward clinical translation of GLT1 (EAAT2) upregulators as treatment for drug addiction might include poor gastrointestinal absorption, serious peripheral adverse effects, and/or suboptimal CNS concentrations. Given the growing success of nanotechnology in targeting CNS ailments, nanoformulating known GLT1 (EAAT2) upregulators for selective uptake across the blood brain barrier presents an ideal therapeutic approach for treating drug addiction. In this review, we summarize the results obtained with promising GLT1 (EAAT2) inducing compounds in animal models recapitulating drug addiction. Additionally, the various nanoformulations that can be employed for selectively increasing the CNS bioavailability of GLT1 (EAAT2) upregulators are discussed. Finally, the applicability of GLT1 (EAAT2) induction via central delivery of drug-loaded nanoformulations is described.

  13. Vesicular glutamate transporters use flexible anion and cation binding sites for efficient accumulation of neurotransmitter.

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    Preobraschenski, Julia; Zander, Johannes-Friedrich; Suzuki, Toshiharu; Ahnert-Hilger, Gudrun; Jahn, Reinhard

    2014-12-17

    Vesicular glutamate transporters (VGLUTs) accumulate the neurotransmitter glutamate in synaptic vesicles. Transport depends on a V-ATPase-dependent electrochemical proton gradient (ΔμH+) and requires chloride ions, but how chloride acts and how ionic and charge balance is maintained during transport is controversial. Using a reconstitution approach, we used an exogenous proton pump to drive VGLUT-mediated transport either in liposomes containing purified VGLUT1 or in synaptic vesicles fused with proton-pump-containing liposomes. Our data show that chloride stimulation can be induced at both sides of the membrane. Moreover, chloride competes with glutamate at high concentrations. In addition, VGLUT1 possesses a cation binding site capable of binding H+ or K+ ions, allowing for proton antiport or K+ / H+ exchange. We conclude that VGLUTs contain two anion binding sites and one cation binding site, allowing the transporter to adjust to the changing ionic conditions during vesicle filling without being dependent on other transporters or channels. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Vesicular monoamine transporter 2 mRNA levels are reduced in platelets from patients with Parkinson's disease.

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    Sala, Gessica; Brighina, Laura; Saracchi, Enrico; Fermi, Silvia; Riva, Chiara; Carrozza, Veronica; Pirovano, Marta; Ferrarese, Carlo

    2010-09-01

    Despite advances in neuroimaging, the diagnosis of idiopathic Parkinson's disease (PD) remains clinical. The identification of biological markers for an early diagnosis is of great interest to start a neuroprotective therapy aimed at slowing, blocking or reversing the disease progression. Vesicular monoamine transporter 2 (VMAT2) sequesters cytoplasmic dopamine into synaptic vesicles for storage and release. Thus, VMAT2 impairment can regulate intra- and extracellular dopamine levels, influencing oxidative stress and neuronal death. Because in vivo imaging studies have demonstrated a VMAT2 reduction in PD patients greater than would be explained by neuronal loss alone, as an exploratory study we assessed VMAT2 mRNA and protein levels in platelets from 39 PD patients, 39 healthy subjects and 10 patients with vascular parkinsonism (VP) to identify a possible peripheral biomarker for PD. A significant reduction (p platelets. Although further studies in a greater number of cases are needed to confirm our data, the reduction in VMAT2 mRNA in platelets from PD patients suggests the existence of a systemic impairment of this transporter possibly contributing to PD pathology.

  15. Essential roles of aspartate aminotransferase 1 and vesicular glutamate transporters in β-cell glutamate signaling for incretin-induced insulin secretion.

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    Naoya Murao

    Full Text Available Incretins (GLP-1 and GIP potentiate insulin secretion through cAMP signaling in pancreatic β-cells in a glucose-dependent manner. We recently proposed a mechanistic model of incretin-induced insulin secretion (IIIS that requires two critical processes: 1 generation of cytosolic glutamate through the malate-aspartate (MA shuttle in glucose metabolism and 2 glutamate transport into insulin granules by cAMP signaling to promote insulin granule exocytosis. To directly prove the model, we have established and characterized CRISPR/Cas9-engineered clonal mouse β-cell lines deficient for the genes critical in these two processes: aspartate aminotransferase 1 (AST1, gene symbol Got1, a key enzyme in the MA shuttle, which generates cytosolic glutamate, and the vesicular glutamate transporters (VGLUT1, VGLUT2, and VGLUT3, gene symbol Slc17a7, Slc17a6, and Slc17a8, respectively, which participate in glutamate transport into secretory vesicles. Got1 knockout (KO β-cell lines were defective in cytosolic glutamate production from glucose and showed impaired IIIS. Unexpectedly, different from the previous finding that global Slc17a7 KO mice exhibited impaired IIIS from pancreatic islets, β-cell specific Slc17a7 KO mice showed no significant impairment in IIIS, as assessed by pancreas perfusion experiment. Single Slc17a7 KO β-cell lines also retained IIIS, probably due to compensatory upregulation of Slc17a6. Interestingly, triple KO of Slc17a7, Slc17a6, and Slc17a8 diminished IIIS, which was rescued by exogenously introduced wild-type Slc17a7 or Slc17a6 genes. The present study provides direct evidence for the essential roles of AST1 and VGLUTs in β-cell glutamate signaling for IIIS and also shows the usefulness of the CRISPR/Cas9 system for studying β-cells by simultaneous disruption of multiple genes.

  16. Expression of vesicular glutamate transporters VGLUT1 and VGLUT2 in the rat dental pulp and trigeminal ganglion following inflammation.

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    Eun Sun Yang

    Full Text Available There is increasing evidence that peripheral glutamate signaling mechanism is involved in the nociceptive transmission during pathological conditions. However, little is known about the glutamate signaling mechanism and related specific type of vesicular glutamate transporter (VGLUT in the dental pulp following inflammation. To address this issue, we investigated expression and protein levels of VGLUT1 and VGLUT2 in the dental pulp and trigeminal ganglion (TG following complete Freund's adjuvant (CFA application to the rat dental pulp by light microscopic immunohistochemistry and Western blot analysis.The density of VGLUT2- immunopositive (+ axons in the dental pulp and the number of VGLUT2+ soma in the TG increased significantly in the CFA-treated group, compared to control group. The protein levels of VGLUT2 in the dental pulp and TG were also significantly higher in the CFA-treated group than control group by Western blot analysis. The density of VGLUT1+ axons in the dental pulp and soma in the TG remained unchanged in the CFA-treated group.These findings suggest that glutamate signaling that is mediated by VGLUT2 in the pulpal axons may be enhanced in the inflamed dental pulp, which may contribute to pulpal axon sensitization leading to hyperalgesia following inflammation.

  17. Vesicular glutamate transporters play a role in neuronal differentiation of cultured SVZ-derived neural precursor cells.

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    Eduardo H Sánchez-Mendoza

    Full Text Available The role of glutamate in the regulation of neurogenesis is well-established, but the role of vesicular glutamate transporters (VGLUTs and excitatory amino acid transporters (EAATs in controlling adult neurogenesis is unknown. Here we investigated the implication of VGLUTs in the differentiation of subventricular zone (SVZ-derived neural precursor cells (NPCs. Our results show that NPCs express VGLUT1-3 and EAAT1-3 both at the mRNA and protein level. Their expression increases during differentiation closely associated with the expression of marker genes. In expression analyses we show that VGLUT1 and VGLUT2 are preferentially expressed by cultured SVZ-derived doublecortin+ neuroblasts, while VGLUT3 is found on GFAP+ glial cells. In cultured NPCs, inhibition of VGLUT by Evans Blue increased the mRNA level of neuronal markers doublecortin, B3T and MAP2, elevated the number of NPCs expressing doublecortin protein and promoted the number of cells with morphological appearance of branched neurons, suggesting that VGLUT function prevents neuronal differentiation of NPCs. This survival- and differentiation-promoting effect of Evans blue was corroborated by increased AKT phosphorylation and reduced MAPK phosphorylation. Thus, under physiological conditions, VGLUT1-3 inhibition, and thus decreased glutamate exocytosis, may promote neuronal differentiation of NPCs.

  18. Methamphetamine promotes habitual action and alters the density of striatal glutamate receptor and vesicular proteins in dorsal striatum.

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    Furlong, Teri M; Corbit, Laura H; Brown, Robert A; Balleine, Bernard W

    2017-07-14

    Goal-directed actions are controlled by the value of the consequences they produce and so increase when what they produce is valuable and decrease when it is not. With continued invariant practice, however, goal-directed actions can become habits, controlled not by their consequences but by antecedent, reward-related states and stimuli. Here, we show that pre-exposure to methamphetamine (METH) caused abnormally rapid development of habitual control. Furthermore, these drug-induced habits differed strikingly from conventional habits; we found that they were insensitive both to changes in reward value and to the effects of negative feedback. In addition to these behavioral changes, METH exposure produced bidirectional changes to synaptic proteins in the dorsal striatum. In the dorsomedial striatum, a structure critical for goal-directed action, METH exposure was associated with a reduction in glutamate receptor and glutamate vesicular proteins, whereas in the dorsolateral striatum, a region that has previously been implicated in habit learning, there was an increase in these proteins. Together, these results indicate that METH exposure promotes habitual control of action that appears to be the result of bidirectional changes in glutamatergic transmission in the circuits underlying goal-directed and habit-based learning. © 2017 Society for the Study of Addiction.

  19. Increased gene expression of selected vesicular and glial glutamate transporters in the frontal cortex in rats exposed to voluntary wheel running.

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    Graban, J; Hlavacova, N; Jezova, D

    2017-10-01

    Though positive effects of exercise on mood and well being are well recognised, the central regulatory mechanisms are still not fully understood. The present study was aimed to testing the hypothesis that voluntary wheel running activates the gene expression of glutamate transporters in the brain cortex of rats. The animals were assigned to the control and voluntary wheel running groups. Voluntary wheel running rats had free access to a stainless steel activity wheel for 3 weeks. The daily running distance gradually increased to 6.21 ± 1.05 km by day 21. Vesicular glutamate transporter 3 (VGLUT3) mRNA levels in the frontal cortex were significantly elevated in the group of running animals compared to the values in sedentary controls, while the expression of other vesicular transporters were unchanged. The concentrations of mRNA coding for glial glutamate transporter 1 (GLT-1), but not glutamate aspartate transporter (GLAST) were increased by running. Voluntary wheel running resulted in an elevation of plasma corticosterone and increased expression of brain derived neurotrophic factor (BDNF) in the frontal cortex. In conclusion, chronic voluntary wheel running results in increased gene expression of VGLUT3 and GLT-1 in the brain cortex without changes in other glutamate transporter subtypes.

  20. Decreased expression of vesicular glutamate transporter 1 and complexin II mRNAs in schizophrenia: further evidence for a synaptic pathology affecting glutamate neurons.

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    Eastwood, S L; Harrison, P J

    2005-03-01

    Synaptic protein gene expression is altered in schizophrenia. In the hippocampal formation there may be particular involvement of glutamatergic neurons and their synapses, but overall the profile remains unclear. In this in situ hybridization histochemistry (ISHH) study, we examined four informative synaptic protein transcripts: vesicular glutamate transporter (VGLUT) 1, VGLUT2, complexin I, and complexin II, in dorsolateral prefrontal cortex (DPFC), superior temporal cortex (STC), and hippocampal formation, in 13 subjects with schizophrenia and 18 controls. In these areas, VGLUT1 and complexin II are expressed primarily by excitatory neurons, whereas complexin I is mainly expressed by inhibitory neurons. In schizophrenia, VGLUT1 mRNA was decreased in hippocampal formation and DPFC, complexin II mRNA was reduced in DPFC and STC, and complexin I mRNA decreased in STC. Hippocampal VGLUT1 mRNA declined with age selectively in the schizophrenia group. VGLUT2 mRNA was not quantifiable due to its low level. The data provide additional evidence for a synaptic pathology in schizophrenia, in terms of a reduced expression of three synaptic protein genes. In the hippocampus, the loss of VGLUT1 mRNA supports data indicating that glutamatergic presynaptic deficits are prominent, whereas the pattern of results in temporal and frontal cortex suggests broadly similar changes may affect inhibitory and excitatory neurons. The impairment of synaptic transmission implied by the synaptic protein reductions may contribute to the dysfunction of cortical neural circuits that characterises the disorder.

  1. Argon blocks the expression of locomotor sensitization to amphetamine through antagonism at the vesicular monoamine transporter-2 and mu-opioid receptor in the nucleus accumbens

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    David, H N; Dhilly, M; Degoulet, M; Poisnel, G; Meckler, C; Vallée, N; Blatteau, J-É; Risso, J-J; Lemaire, M; Debruyne, D; Abraini, J H

    2015-01-01

    We investigated the effects of the noble gas argon on the expression of locomotor sensitization to amphetamine and amphetamine-induced changes in dopamine release and mu-opioid neurotransmission in the nucleus accumbens. We found (1) argon blocked the increase in carrier-mediated dopamine release induced by amphetamine in brain slices, but, in contrast, potentiated the decrease in KCl-evoked dopamine release induced by amphetamine, thereby suggesting that argon inhibited the vesicular monoamine transporter-2; (2) argon blocked the expression of locomotor and mu-opioid neurotransmission sensitization induced by repeated amphetamine administration in a short-term model of sensitization in rats; (3) argon decreased the maximal number of binding sites and increased the dissociation constant of mu-receptors in membrane preparations, thereby indicating that argon is a mu-receptor antagonist; (4) argon blocked the expression of locomotor sensitization and context-dependent locomotor activity induced by repeated administration of amphetamine in a long-term model of sensitization. Taken together, these data indicate that argon could be of potential interest for treating drug addiction and dependence. PMID:26151922

  2. Fluoroethoxy-1,4-diphenethylpiperidine and piperazine derivatives: Potent and selective inhibitors of [3H]dopamine uptake at the vesicular monoamine transporter-2.

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    Hankosky, Emily R; Joolakanti, Shyam R; Nickell, Justin R; Janganati, Venumadhav; Dwoskin, Linda P; Crooks, Peter A

    2017-12-15

    A small library of fluoroethoxy-1,4-diphenethyl piperidine and fluoroethoxy-1,4-diphenethyl piperazine derivatives were designed, synthesized and evaluated for their ability to inhibit [3H]dopamine (DA) uptake at the vesicular monoamine transporter-2 (VMAT2) and dopamine transporter (DAT), [3H]serotonin (5-HT) uptake at the serotonin transporter (SERT), and [3H]dofetilide binding at the human-ether-a-go-go-related gene (hERG) channel. The majority of the compounds exhibited potent inhibition of [3H]DA uptake at VMAT2, Ki changes in the nanomolar range (Ki = 0.014-0.073 µM). Compound 15d exhibited the highest affinity (Ki = 0.014 µM) at VMAT2, and had 160-, 5-, and 60-fold greater selectivity for VMAT2 vs. DAT, SERT and hERG, respectively. Compound 15b exhibited the greatest selectivity (>60-fold) for VMAT2 relative to all the other targets evaluated, and 15b had high affinity for VMAT2 (Ki = 0.073 µM). Compound 15b was considered the lead compound from this analog series due to its high affinity and selectivity for VMAT2. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Characterization of depolarization-coupled release of glutamate from cultured mouse cerebellar granule cells using DL-threo-beta-benzyloxyaspartate (DL-TBOA) to distinguish between the vesicular and cytoplasmic pools

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    Bak, Lasse K; Schousboe, Arne; Waagepetersen, Helle S

    2003-01-01

    Release of preloaded [3H]D-aspartate in response to depolarization induced by N-methyl-D-aspartate (NMDA) or the endogenous agonist glutamate was characterized using cultured glutamatergic cerebellar granule neurons. Release from the vesicular and the cytoplasmic glutamate pools, respectively, wa...

  4. Another Imaginary World: The ICER Claims for the Long-Term Cost-Effectiveness and Pricing of Vesicular Monoamine Transporter 2 (VMAT2 Inhibitors in Tardive Dyskinesia

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    Paul C. Langley

    2017-10-01

    Full Text Available The recently released value assessment of vesicular monoamine transporter 2 (VMAT2 inhibitors in tardive dyskinesia by the Institute for Clinical and Economic Review (ICER relies upon a long-term modeling exercise to support recommendations for what the ICER sees as the appropriate pricing for these products if prices are to be judged ‘cost-effective’. In this case, the recommendations are for a substantive price reduction of some 90% over WAC. Needless to say, this recommendation is unlikely to be welcomed with open arms by the respective manufacturers of valbenazine and deutetrabenazine. Unfortunately, as has been argued in a number of commentaries published over the past 18 months in INNOVATIONS in Pharmacy, the ICER endorsed health technology assessment methodology that underpins this exercise in building a modeled imaginary world to justify product pricing recommendations is fatally flawed: it does not meet the standards of normal science. Rather than addressing the issue of claims validation for VMAT2 products, the question of generating modeled evaluable claims, among others, for clinical, quality of life and resource utilization outcomes, the analysis focuses on claims that are neither credible nor evaluable and, of course, non-replicable. A more positive and useful approach would be for ICER to focus on a framework where claims could be assessed in the short term to provide feedback to health system decision makers, physicians and patients. Instead, we are asked to believe that we can model 20 or 30 years into the future to establish non-evaluable claims for pricing and, ultimately, access. Conflict of Interest: None   Type: Commentary

  5. Depolarization by K+ and glutamate activates different neurotransmitter release mechanisms in GABAergic neurons: vesicular versus non-vesicular release of GABA

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    Belhage, B; Hansen, Gert Helge; Schousboe, A

    1993-01-01

    Neurotransmitter release and changes in the concentration of intracellular free calcium ([Ca++]i) were studied in cultured GABAergic cerebral cortical neurons, from mice, upon depolarization with either an unphysiologically high potassium concentration (55 mM) or the physiological excitatory...... neurotransmitter glutamate (100 microM). Both depolarizing stimuli exerted prompt increases in the release of preloaded [3H]GABA as well as in [Ca++]i. However, the basic properties of transmitter release and the increase in [Ca++]i under a variety of conditions were different during stimulation with K...... in nature whereas that induced by the neurotransmitter glutamate is not....

  6. Depolarization by K+ and glutamate activates different neurotransmitter release mechanisms in GABAergic neurons: vesicular versus non-vesicular release of GABA

    DEFF Research Database (Denmark)

    Belhage, B; Hansen, G H; Schousboe, A

    1993-01-01

    was also reduced by organic (verapamil) and inorganic (Co++) Ca++ channel blockers but was insensitive to the GABA transport inhibitor SKF 89976A. In contrast, the second phase was less sensitive to nocodazole and Ca++ channel antagonists but could be inhibited by SKF 89976A. The glutamate-induced [3H...

  7. Mechanism of ceftriaxone induction of excitatory amino acid transporter-2 expression and glutamate uptake in primary human astrocytes.

    Science.gov (United States)

    Lee, Seok-Geun; Su, Zhao-Zhong; Emdad, Luni; Gupta, Pankaj; Sarkar, Devanand; Borjabad, Alejandra; Volsky, David J; Fisher, Paul B

    2008-05-09

    Glutamate is an essential neurotransmitter regulating brain functions. Excitatory amino acid transporter (EAAT)-2 is one of the major glutamate transporters primarily expressed in astroglial cells. Dysfunction of EAAT2 is implicated in acute and chronic neurological disorders, including stroke/ischemia, temporal lobe epilepsy, amyotrophic lateral sclerosis, Alzheimer disease, human immunodeficiency virus 1-associated dementia, and growth of malignant gliomas. Ceftriaxone, one of the beta-lactam antibiotics, is a stimulator of EAAT2 expression with neuroprotective effects in both in vitro and in vivo models based in part on its ability to inhibit neuronal cell death by glutamate excitotoxicity. Based on this consideration and its lack of toxicity, ceftriaxone has potential to manipulate glutamate transmission and ameliorate neurotoxicity. We investigated the mechanism by which ceftriaxone enhances EAAT2 expression in primary human fetal astrocytes (PHFA). Ceftriaxone elevated EAAT2 transcription in PHFA through the nuclear factor-kappaB (NF-kappaB) signaling pathway. The antibiotic promoted nuclear translocation of p65 and activation of NF-kappaB. The specific NF-kappaB binding site at the -272 position of the EAAT2 promoter was responsible for ceftriaxone-mediated EAAT2 induction. In addition, ceftriaxone increased glutamate uptake, a primary function of EAAT2, and EAAT2 small interference RNA completely inhibited ceftriaxone-induced glutamate uptake activity in PHFA. Taken together, our data indicate that ceftriaxone is a potent modulator of glutamate transport in PHFA through NF-kappaB-mediated EAAT2 promoter activation. These findings suggest a mechanism for ceftriaxone modulation of glutamate transport and for its potential effects on ameliorating specific neurodegenerative diseases through modulation of extracellular glutamate.

  8. Coexpression of glutamate vesicular transporter (VGLUT1) and choline acetyltransferase (ChAT) proteins in fetal rat hippocampal neurons in culture.

    Science.gov (United States)

    Bhargava, Neelima; Das, Mainak; Edwards, Darin; Stancescu, Maria; Kang, Jung-Fong; Hickman, James J

    2010-09-01

    A very small population of choline acetyltransferase (ChAT) immunoreactive cells is observed in all layers of the adult hippocampus. This is the intrinsic source of the hippocampal cholinergic innervation, in addition to the well-established septo-hippocampal cholinergic projection. This study aimed at quantifying and identifying the origin of this small population of ChAT-immunoreactive cells in the hippocampus at early developmental stages, by culturing the fetal hippocampal neurons in serum-free culture and on a patternable, synthetic silane substrate N-1 [3-(trimethoxysilyl) propyl] diethylenetriamine. Using this method, a large proportion of glutamatergic (glutamate vesicular transporter, VGLUT1-immunoreactive) neurons, a small fraction of GABAergic (GABA-immunoreactive) neurons, and a large proportion of cholinergic (ChAT-immunoreactive) neurons were observed in the culture. Interestingly, most of the glutamatergic neurons that expressed glutamate vesicular transporter (VGLUT1) also co-expressed ChAT proteins. On the contrary, when the cultures were double-stained with GABA and ChAT, colocalization was not observed. Neonatal and adult rat hippocampal neurons were also cultured to verify whether these more mature neurons also co-express VGLUT1 and ChAT proteins in culture. Colocalization of VGLUT1 and ChAT in these relatively more mature neurons was not observed. One possible explanation for this observation is that the neurons have the ability to synthesize multiple neurotransmitters at a very early stage of development and then with time follows a complex, combinatorial strategy of electrochemical coding to determine their final fate.

  9. High-frequency stimulation of the subthalamic nucleus modifies the expression of vesicular glutamate transporters in basal ganglia in a rat model of Parkinson's disease.

    Science.gov (United States)

    Favier, Mathieu; Carcenac, Carole; Drui, Guillaume; Boulet, Sabrina; El Mestikawy, Salah; Savasta, Marc

    2013-12-05

    It has been suggested that glutamatergic system hyperactivity may be related to the pathogenesis of Parkinson's disease (PD). Vesicular glutamate transporters (VGLUT1-3) import glutamate into synaptic vesicles and are key anatomical and functional markers of glutamatergic excitatory transmission. Both VGLUT1 and VGLUT2 have been identified as definitive markers of glutamatergic neurons, but VGLUT 3 is also expressed by non glutamatergic neurons. VGLUT1 and VGLUT2 are thought to be expressed in a complementary manner in the cortex and the thalamus (VL/VM), in glutamatergic neurons involved in different physiological functions. Chronic high-frequency stimulation (HFS) of the subthalamic nucleus (STN) is the neurosurgical therapy of choice for the management of motor deficits in patients with advanced PD. STN-HFS is highly effective, but its mechanisms of action remain unclear. This study examines the effect of STN-HFS on VGLUT1-3 expression in different brain nuclei involved in motor circuits, namely the basal ganglia (BG) network, in normal and 6-hydroxydopamine (6-OHDA) lesioned rats. Here we report that: 1) Dopamine(DA)-depletion did not affect VGLUT1 and VGLUT3 expression but significantly decreased that of VGLUT2 in almost all BG structures studied; 2) STN-HFS did not change VGLUT1-3 expression in the different brain areas of normal rats while, on the contrary, it systematically induced a significant increase of their expression in DA-depleted rats and 3) STN-HFS reversed the decrease in VGLUT2 expression induced by the DA-depletion. These results show for the first time a comparative analysis of changes of expression for the three VGLUTs induced by STN-HFS in the BG network of normal and hemiparkinsonian rats. They provide evidence for the involvement of VGLUT2 in the modulation of BG cicuits and in particular that of thalamostriatal and thalamocortical pathways suggesting their key role in its therapeutic effects for alleviating PD motor symptoms.

  10. Bacopa monnieri (Brahmi) improved novel object recognition task and increased cerebral vesicular glutamate transporter type 3 in sub-chronic phencyclidine rat model of schizophrenia.

    Science.gov (United States)

    Piyabhan, Pritsana; Wannasiri, Supaporn; Naowaboot, Jarinyaporn

    2016-12-01

    Reduced vesicular glutamate transporter 1 (VGLUT1) and 2 (VGLUT2) indicate glutamatergic hypofunction leading to cognitive impairment in schizophrenia. However, VGLUT3 involvement in cognitive dysfunction has not been reported in schizophrenia. Brahmi (Bacopa monnieri) might be a new treatment and prevention for cognitive deficits in schizophrenia by acting on cerebral VGLUT3 density. We aimed to study cognitive enhancement- and neuroprotective-effects of Brahmi on novel object recognition and cerebral VGLUT3 immunodensity in sub-chronic (2 mg/kg, Bid, ip) phencyclidine (PCP) rat model of schizophrenia. Rats were assigned to three groups for cognitive enhancement effect study: Group 1, Control; Group 2, PCP administration; Group 3, PCP+Brahmi. A neuroprotective-effect study was also carried out. Rats were again assigned to three groups: Group 1, Control; Group 2, PCP administration; Group 3, Brahmi+PCP. Discrimination ratio (DR) representing cognitive ability was obtained from a novel object recognition task. VGLUT3 immunodensity was measured in the prefrontal cortex, striatum and cornu ammonis fields 1-3 (CA1-3) using immunohistochemistry. We found reduced DR in the PCP group, which occurred alongside VGLUT3 reduction in all brain areas. PCP+Brahmi showed higher DR score with increased VGLUT3 immunodensity in the prefrontal cortex and striatum. Brahmi+PCP group showed a higher DR score with increased VGLUT3 immunodensity in the prefrontal cortex, striatum and CA1-3. We concluded that reduced cerebral VGLUT3 was involved in cognitive deficit in PCP-administrated rats. Receiving Brahmi after PCP restored cognitive deficit by increasing VGLUT3 in the prefrontal cortex and striatum. Receiving Brahmi before PCP prevented cognitive impairment by elevating VGLUT3 in prefrontal cortex, striatum and CA1-3. Therefore, Brahmi could be a new frontier of restoration and prevention of cognitive deficit in schizophrenia. © 2016 John Wiley & Sons Australia, Ltd.

  11. Coexpression of Tyrosine Hydroxylase, GTP Cyclohydrolase I, Aromatic Amino Acid Decarboxylase, and Vesicular Monoamine Transporter 2 from a Helper Virus-Free Herpes Simplex Virus Type 1 Vector Supports High-Level, Long-Term Biochemical and Behavioral Correction of a Rat Model of Parkinson’s Disease

    Science.gov (United States)

    SUN, MEI; KONG, LINGXIN; WANG, XIAODAN; HOLMES, COURTNEY; GAO, QINGSHENG; ZHANG, GUO-RONG; PFEILSCHIFTER, JOSEF; GOLDSTEIN, DAVID S.; GELLER, ALFRED I.

    2006-01-01

    normal rats, and only the 4-gene-vector supported significant K+-dependent release of dopamine. OVERVIEW SUMMARY Gene therapy treatments may benefit the management of Parkinson’s disease (PD). In the present study, we used a helper virus-free herpes simplex virus type 1 (HSV-1) vector system and a modified neurofilament heavy gene promoter that supports long-term expression in forebrain neurons. We coexpressed tyrosine hydroxylase, GTP cyclohydrolase I, aromatic amino acid decarboxylase, and vesicular monoamine transporter 2 in striatal cells in the 6-hydroxydopamine rat model of PD. Recombinant gene expression was maintained for 14 months in γ-aminobutyric acid (GABA)-ergic striatal neurons. Long-term behavioral (6 months) and biochemical (3 months) correction was observed with high K+-dependent release of significant levels of dopamine. These results suggest that HSV-1 vectors that coexpress multiple dopamine biosynthetic and transporter genes have promise for developing gene therapy treatments for PD. PMID:15684695

  12. Identification of a vesicular aspartate transporter

    Science.gov (United States)

    Miyaji, Takaaki; Echigo, Noriko; Hiasa, Miki; Senoh, Shigenori; Omote, Hiroshi; Moriyama, Yoshinori

    2008-01-01

    Aspartate is an excitatory amino acid that is costored with glutamate in synaptic vesicles of hippocampal neurons and synaptic-like microvesicles (SLMVs) of pinealocytes and is exocytosed and stimulates neighboring cells by binding to specific cell receptors. Although evidence increasingly supports the occurrence of aspartergic neurotransmission, this process is still debated because the mechanism for the vesicular storage of aspartate is unknown. Here, we show that sialin, a lysosomal H+/sialic acid cotransporter, is present in hippocampal synaptic vesicles and pineal SLMVs. RNA interference of sialin expression decreased exocytosis of aspartate and glutamate in pinealocytes. Proteoliposomes containing purified sialin actively accumulated aspartate and glutamate to a similar extent when inside positive membrane potential is imposed as the driving force. Sialin carrying a mutation found in people suffering from Salla disease (R39C) was completely devoid of aspartate and glutamate transport activity, although it retained appreciable H+/sialic acid cotransport activity. These results strongly suggest that sialin possesses dual physiological functions and acts as a vesicular aspartate/glutamate transporter. It is possible that people with Salla disease lose aspartergic (and also the associated glutamatergic) neurotransmission, and this could provide an explanation for why Salla disease causes severe neurological defects. PMID:18695252

  13. Identification of a vesicular aspartate transporter

    OpenAIRE

    Miyaji, Takaaki; Echigo, Noriko; Hiasa, Miki; Senoh, Shigenori; Omote, Hiroshi; Moriyama, Yoshinori

    2008-01-01

    Aspartate is an excitatory amino acid that is costored with glutamate in synaptic vesicles of hippocampal neurons and synaptic-like microvesicles (SLMVs) of pinealocytes and is exocytosed and stimulates neighboring cells by binding to specific cell receptors. Although evidence increasingly supports the occurrence of aspartergic neurotransmission, this process is still debated because the mechanism for the vesicular storage of aspartate is unknown. Here, we show that sialin, a lysosomal H+/sia...

  14. Glutamate and GABA in vestibulo-sympathetic pathway neurons

    Directory of Open Access Journals (Sweden)

    Gay R Holstein

    2016-02-01

    Full Text Available The vestibulo-sympathetic reflex actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The vestibulo-sympathetic reflex pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively. The present study assessed glutamate- and GABA-related immunofluorescence associated with central vestibular neurons of the vestibulo-sympathetic reflex pathway in rats. Retrograde FluoroGold tract tracing was used to label vestibular neurons with projections to RVLM or CVLM, and sinusoidal galvanic vestibular stimulation was employed to activate these pathways. Central vestibular neurons of the vestibulo-sympathetic reflex were identified by co-localization of FluoroGold and cFos protein, which accumulates in some vestibular neurons following galvanic stimulation. Triple-label immunofluorescence was used to co-localize glutamate- or GABA- labeling in the identified vestibulo-sympathetic reflex pathway neurons. Most activated projection neurons displayed intense glutamate immunofluorescence, suggestive of glutamatergic neurotransmission. To support this, anterograde tracer was injected into the caudal vestibular nuclei. Vestibular axons and terminals in RVLM and CVLM co-localized the anterograde tracer and vesicular glutamate transporter-2 signals. Other retrogradely-labeled cFos-positive neurons displayed intense GABA immunofluorescence. Vestibulo-sympathetic reflex pathway neurons of both phenotypes were present in the caudal medial and spinal vestibular nuclei, and projected to both RVLM and CVLM. As a group, however, triple-labeled vestibular cells with intense glutamate immunofluorescence were located more rostrally in the vestibular nuclei than the GABAergic neurons. Only the

  15. Are vesicular neurotransmitter transporters potential treatment targets for temporal lobe epilepsy?

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    Joeri eVan Liefferinge

    2013-08-01

    Full Text Available The vesicular neurotransmitter transporters (VNTs are small proteins responsible for packing synaptic vesicles with neurotransmitters thereby determining the amount of neurotransmitter released per vesicle through fusion in both neurons and glial cells. Each transporter subtype was classically seen as a specific neuronal marker of the respective nerve cells containing that particular neurotransmitter or structurally related neurotransmitters. More recently, however, it has become apparent that common neurotransmitters can also act as co-transmitters, adding complexity to neurotransmitter release and suggesting intriguing roles for VNTs therein. We will first describe the current knowledge on vesicular glutamate transporters (VGLUT1/2/3, the vesicular excitatory amino acid transporter (VEAT, the vesicular nucleotide transporter (VNUT, vesicular monoamine transporters (VMAT1/2, the vesicular acetylcholine transporter (VAChT and the vesicular γ-aminobutyric acid (GABA transporter (VGAT in the brain. We will focus on evidence regarding transgenic mice with disruptions in VNTs in different models of seizures and epilepsy. We will also describe the known alterations and reorganizations in the expression levels of these VNTs in rodent models for temporal lobe epilepsy (TLE and in human tissue resected for epilepsy surgery. Finally, we will discuss perspectives on opportunities and challenges for VNTs as targets for possible future epilepsy therapies.

  16. Valine but not leucine or isoleucine supports neurotransmitter glutamate synthesis during synaptic activity in cultured cerebellar neurons

    DEFF Research Database (Denmark)

    Bak, Lasse Kristoffer; Johansen, Maja L.; Schousboe, Arne

    2012-01-01

    Synthesis of neuronal glutamate from a-ketoglutarate for neurotransmission necessitates an amino group nitrogen donor; however, it is not clear which amino acid(s) serves this role. Thus, the ability of the three branched-chain amino acids (BCAAs), leucine, isoleucine, and valine, to act as amino...... group nitrogen donors for synthesis of vesicular neurotransmitter glutamate was investigated in cultured mouse cerebellar (primarily glutamatergic) neurons. The cultures were superfused in the presence of (15) N-labeled BCAAs, and synaptic activity was induced by pulses of N-methyl-D-aspartate (300 µ......]valine was able to maintain the amount of vesicular glutamate during synaptic activity. This indicates that, among the BCAAs, only valine supports the increased need for synthesis of vesicular glutamate. © 2012 Wiley Periodicals, Inc....

  17. Genetic inactivation of glutamate neurons in the rat sublaterodorsal tegmental nucleus recapitulates REM sleep behaviour disorder.

    Science.gov (United States)

    Valencia Garcia, Sara; Libourel, Paul-Antoine; Lazarus, Michael; Grassi, Daniela; Luppi, Pierre-Hervé; Fort, Patrice

    2017-02-01

    SEE SCHENCK AND MAHOWALD DOI101093/AWW329 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Idiopathic REM sleep behaviour disorder is characterized by the enactment of violent dreams during paradoxical (REM) sleep in the absence of normal muscle atonia. Accumulating clinical and experimental data suggest that REM sleep behaviour disorder might be due to the neurodegeneration of glutamate neurons involved in paradoxical sleep and located within the pontine sublaterodorsal tegmental nucleus. The purpose of the present work was thus to functionally determine first, the role of glutamate sublaterodorsal tegmental nucleus neurons in paradoxical sleep and second, whether their genetic inactivation is sufficient for recapitulating REM sleep behaviour disorder in rats. For this goal, we first injected two retrograde tracers in the intralaminar thalamus and ventral medulla to disentangle neuronal circuits in which sublaterodorsal tegmental nucleus is involved; second we infused bilaterally in sublaterodorsal tegmental nucleus adeno-associated viruses carrying short hairpin RNAs targeting Slc17a6 mRNA [which encodes vesicular glutamate transporter 2 (vGluT2)] to chronically impair glutamate synaptic transmission in sublaterodorsal tegmental nucleus neurons. At the neuroanatomical level, sublaterodorsal tegmental nucleus neurons specifically activated during paradoxical sleep hypersomnia send descending efferents to glycine/GABA neurons within the ventral medulla, but not ascending projections to the intralaminar thalamus. These data suggest a crucial role of sublaterodorsal tegmental nucleus neurons rather in muscle atonia than in paradoxical sleep generation. In line with this hypothesis, 30 days after adeno-associated virus injections into sublaterodorsal tegmental nucleus rats display a decrease of 30% of paradoxical sleep daily quantities, and a significant increase of muscle tone during paradoxical sleep concomitant to a tremendous increase of abnormal motor dream

  18. Role of astrocytes in depolarization-coupled release of glutamate in cerebellar cultures

    DEFF Research Database (Denmark)

    Bak, Lasse K; Waagepetersen, Helle S; Schousboe, Arne

    2004-01-01

    to AMPA (30 microM) in the presence of cyclothiazide (50 microM) to block desensitization, was of a vesicular origin. Pulses of 55 mM K+ caused a DL-TBOA resistant efflux of preloaded D-[3H]aspartate from astrocytes, indicating that this release was not mediated by glutamate transporters. The results...

  19. Motor axon synapses on renshaw cells contain higher levels of aspartate than glutamate.

    Directory of Open Access Journals (Sweden)

    Dannette S Richards

    Full Text Available Motoneuron synapses on spinal cord interneurons known as Renshaw cells activate nicotinic, AMPA and NMDA receptors consistent with co-release of acetylcholine and excitatory amino acids (EAA. However, whether these synapses express vesicular glutamate transporters (VGLUTs capable of accumulating glutamate into synaptic vesicles is controversial. An alternative possibility is that these synapses release other EAAs, like aspartate, not dependent on VGLUTs. To clarify the exact EAA concentrated at motor axon synapses we performed a quantitative postembedding colloidal gold immunoelectron analysis for aspartate and glutamate on motor axon synapses (identified by immunoreactivity to the vesicular acetylcholine transporter; VAChT contacting calbindin-immunoreactive (-IR Renshaw cell dendrites. The results show that 71% to 80% of motor axon synaptic boutons on Renshaw cells contained aspartate immunolabeling two standard deviations above average neuropil labeling. Moreover, VAChT-IR synapses on Renshaw cells contained, on average, aspartate immunolabeling at 2.5 to 2.8 times above the average neuropil level. In contrast, glutamate enrichment was lower; 21% to 44% of VAChT-IR synapses showed glutamate-IR two standard deviations above average neuropil labeling and average glutamate immunogold density was 1.7 to 2.0 times the neuropil level. The results were not influenced by antibody affinities because glutamate antibodies detected glutamate-enriched brain homogenates more efficiently than aspartate antibodies detecting aspartate-enriched brain homogenates. Furthermore, synaptic boutons with ultrastructural features of Type I excitatory synapses were always labeled by glutamate antibodies at higher density than motor axon synapses. We conclude that motor axon synapses co-express aspartate and glutamate, but aspartate is concentrated at higher levels than glutamate.

  20. Evidence for a role of glutamate as an efferent transmitter in taste buds

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    Anderson Catherine B

    2010-06-01

    Full Text Available Abstract Background Glutamate has been proposed as a transmitter in the peripheral taste system in addition to its well-documented role as an umami taste stimulus. Evidence for a role as a transmitter includes the presence of ionotropic glutamate receptors in nerve fibers and taste cells, as well as the expression of the glutamate transporter GLAST in Type I taste cells. However, the source and targets of glutamate in lingual tissue are unclear. In the present study, we used molecular, physiological and immunohistochemical methods to investigate the origin of glutamate as well as the targeted receptors in taste buds. Results Using molecular and immunohistochemical techniques, we show that the vesicular transporters for glutamate, VGLUT 1 and 2, but not VGLUT3, are expressed in the nerve fibers surrounding taste buds but likely not in taste cells themselves. Further, we show that P2X2, a specific marker for gustatory but not trigeminal fibers, co-localizes with VGLUT2, suggesting the VGLUT-expressing nerve fibers are of gustatory origin. Calcium imaging indicates that GAD67-GFP Type III taste cells, but not T1R3-GFP Type II cells, respond to glutamate at concentrations expected for a glutamate transmitter, and further, that these responses are partially blocked by NBQX, a specific AMPA/Kainate receptor antagonist. RT-PCR and immunohistochemistry confirm the presence of the Kainate receptor GluR7 in Type III taste cells, suggesting it may be a target of glutamate released from gustatory nerve fibers. Conclusions Taken together, the results suggest that glutamate may be released from gustatory nerve fibers using a vesicular mechanism to modulate Type III taste cells via GluR7.

  1. Vesicular stomatitis forecasting based on Google Trends

    Science.gov (United States)

    Lu, Yi; Zhou, GuangYa; Chen, Qin

    2018-01-01

    Background Vesicular stomatitis (VS) is an important viral disease of livestock. The main feature of VS is irregular blisters that occur on the lips, tongue, oral mucosa, hoof crown and nipple. Humans can also be infected with vesicular stomatitis and develop meningitis. This study analyses 2014 American VS outbreaks in order to accurately predict vesicular stomatitis outbreak trends. Methods American VS outbreaks data were collected from OIE. The data for VS keywords were obtained by inputting 24 disease-related keywords into Google Trends. After calculating the Pearson and Spearman correlation coefficients, it was found that there was a relationship between outbreaks and keywords derived from Google Trends. Finally, the predicted model was constructed based on qualitative classification and quantitative regression. Results For the regression model, the Pearson correlation coefficients between the predicted outbreaks and actual outbreaks are 0.953 and 0.948, respectively. For the qualitative classification model, we constructed five classification predictive models and chose the best classification predictive model as the result. The results showed, SN (sensitivity), SP (specificity) and ACC (prediction accuracy) values of the best classification predictive model are 78.52%,72.5% and 77.14%, respectively. Conclusion This study applied Google search data to construct a qualitative classification model and a quantitative regression model. The results show that the method is effective and that these two models obtain more accurate forecast. PMID:29385198

  2. Local anesthetics inhibit glutamate release from rat cerebral cortex synaptosomes.

    Science.gov (United States)

    Lin, Tzu-Yu; Chung, Chih-Yang; Lu, Cheng-Wei; Huang, Shu-Kuei; Shieh, Jiann-Sing; Wang, Su-Jane

    2013-09-01

    Local anesthetics have been widely used for regional anesthesia and the treatment of cardiac arrhythmias. Recent studies have also demonstrated that low-dose systemic local anesthetic infusion has neuroprotective properties. Considering the fact that excessive glutamate release can cause neuronal excitotoxicity, we investigated whether local anesthetics might influence glutamate release from rat cerebral cortex nerve terminals (synaptosomes). Results showed that two commonly used local anesthetics, lidocaine and bupivacaine, exhibited a dose-dependent inhibition of 4-AP-evoked release of glutamate. The effects of lidocaine or bupivacaine on the evoked glutamate release were prevented by the chelation of extracellular Ca²⁺ ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor dl-threo-beta-benzyl-oxyaspartate did not have any effect on the action of lidocaine or bupivacaine. Both lidocaine and bupivacaine reduced the depolarization-induced increase in [Ca²⁺]C but did not alter 4-AP-mediated depolarization. Furthermore, the inhibitory effect of lidocaine or bupivacaine on evoked glutamate release was prevented by blocking the Ca(v)2.2 (N-type) and Ca(v)2.1 (P/Q-type) channels, but it was not affected by blocking of the ryanodine receptors or the mitochondrial Na⁺/Ca²⁺ exchange. Inhibition of protein kinase C (PKC) and protein kinase A (PKA) also prevented the action of lidocaine or bupivacaine. These results show that local anesthetics inhibit glutamate release from rat cortical nerve terminals. This effect is linked to a decrease in [Ca²⁺]C caused by Ca²⁺ entry through presynaptic voltage-dependent Ca²⁺ channels and the suppression of the PKA and PKC signaling cascades. Copyright © 2013 Wiley Periodicals, Inc.

  3. A role for glutamate transporters in the regulation of insulin secretion.

    Directory of Open Access Journals (Sweden)

    Runhild Gammelsaeter

    Full Text Available In the brain, glutamate is an extracellular transmitter that mediates cell-to-cell communication. Prior to synaptic release it is pumped into vesicles by vesicular glutamate transporters (VGLUTs. To inactivate glutamate receptor responses after release, glutamate is taken up into glial cells or neurons by excitatory amino acid transporters (EAATs. In the pancreatic islets of Langerhans, glutamate is proposed to act as an intracellular messenger, regulating insulin secretion from β-cells, but the mechanisms involved are unknown. By immunogold cytochemistry we show that insulin containing secretory granules express VGLUT3. Despite the fact that they have a VGLUT, the levels of glutamate in these granules are low, indicating the presence of a protein that can transport glutamate out of the granules. Surprisingly, in β-cells the glutamate transporter EAAT2 is located, not in the plasma membrane as it is in brain cells, but exclusively in insulin-containing secretory granules, together with VGLUT3. In EAAT2 knock out mice, the content of glutamate in secretory granules is higher than in wild type mice. These data imply a glutamate cycle in which glutamate is carried into the granules by VGLUT3 and carried out by EAAT2. Perturbing this cycle by knocking down EAAT2 expression with a small interfering RNA, or by over-expressing EAAT2 or a VGLUT in insulin granules, significantly reduced the rate of granule exocytosis. Simulations of granule energetics suggest that VGLUT3 and EAAT2 may regulate the pH and membrane potential of the granules and thereby regulate insulin secretion. These data suggest that insulin secretion from β-cells is modulated by the flux of glutamate through the secretory granules.

  4. VGLUTs and Glutamate Synthesis—Focus on DRG Neurons and Pain

    Directory of Open Access Journals (Sweden)

    Mariana Malet

    2015-12-01

    Full Text Available The amino acid glutamate is the principal excitatory transmitter in the nervous system, including in sensory neurons that convey pain sensation from the periphery to the brain. It is now well established that a family of membrane proteins, termed vesicular glutamate transporters (VGLUTs, serve a critical function in these neurons: they incorporate glutamate into synaptic vesicles. VGLUTs have a central role both under normal neurotransmission and pathological conditions, such as neuropathic or inflammatory pain. In the present short review, we will address VGLUTs in the context of primary afferent neurons. We will focus on the role of VGLUTs in pain triggered by noxious stimuli, peripheral nerve injury, and tissue inflammation, as mostly explored in transgenic mice. The possible interplay between glutamate biosynthesis and VGLUT-dependent packaging in synaptic vesicles, and its potential impact in various pain states will be presented.

  5. Synaptopathy under conditions of altered gravity: changes in synaptic vesicle fusion and glutamate release.

    Science.gov (United States)

    Krisanova, N V; Trikash, I O; Borisova, T A

    2009-12-01

    Glutamate release and synaptic vesicle heterotypic/homotypic fusion were characterized in brain synaptosomes of rats exposed to hypergravity (10 G, 1h). Stimulated vesicular exocytosis determined as KCl-evoked fluorescence spike of pH-sensitive dye acridine orange (AO) was decreased twice in synaptosomes under hypergravity conditions as compared to control. Sets of measurements demonstrated reduced ability of synaptic vesicles to accumulate AO ( approximately 10% higher steady-state baseline level of AO fluorescence). Experiments with preloaded l-[(14)C]glutamate exhibited similar amount of total glutamate accumulated by synaptosomes, equal concentration of ambient glutamate, but the enlarged level of cytoplasmic glutamate measuring as leakage from digitonin-permeabilized synaptosomes in hypergravity. Thus, it may be suggested that +G-induced changes in stimulated vesicular exocytosis were a result of the redistribution of intracellular pool of glutamate, i.e. a decrease in glutamate content of synaptic vesicles and an enrichment of the cytoplasmic glutamate level. To investigate the effect of hypergravity on the last step of exocytosis, i.e. membrane fusion, a cell-free system consisted of synaptic vesicles, plasma membrane vesicles, cytosolic proteins isolated from rat brain synaptosomes was used. It was found that hypergravity reduced the fusion competence of synaptic vesicles and plasma membrane vesicles, whereas synaptosomal cytosolic proteins became more active to promote membrane fusion. The total rate of homo- and heterotypic fusion reaction initiated by Ca(2+) or Mg(2+)/ATP remained unchanged under hypergravity conditions. Thus, hypergravity could induce synaptopathy that was associated with incomplete filling of synaptic vesicles with the neuromediator and changes in exocytotic release.

  6. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart

    2011-01-01

    The neurotransmitter (S)-glutamate [(S)-Glu] is responsible for most of the excitatory neurotransmission in the central nervous system. The effect of (S)-Glu is mediated by both ionotropic and metabotropic receptors. Glutamate receptor agonists are generally a-amino acids with one or more...... stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...... mainly on agonists and discusses stereochemical and conformational considerations as well as biostructural knowledge of the agonist binding pockets, which is useful in the design of glutamate receptor agonists. Examples are chosen to demonstrate how stereochemistry not only determines how the agonist...

  7. History of glutamate production.

    Science.gov (United States)

    Sano, Chiaki

    2009-09-01

    In 1907 Kikunae Ikeda, a professor at the Tokyo Imperial University, began his research to identify the umami component in kelp. Within a year, he had succeeded in isolating, purifying, and identifying the principal component of umami and quickly obtained a production patent. In 1909 Saburosuke Suzuki, an entrepreneur, and Ikeda began the industrial production of monosodium l-glutamate (MSG). The first industrial production process was an extraction method in which vegetable proteins were treated with hydrochloric acid to disrupt peptide bonds. l-Glutamic acid hydrochloride was then isolated from this material and purified as MSG. Initial production of MSG was limited because of the technical drawbacks of this method. Better methods did not emerge until the 1950s. One of these was direct chemical synthesis, which was used from 1962 to 1973. In this procedure, acrylonitrile was the starting material, and optical resolution of dl-glutamic acid was achieved by preferential crystallization. In 1956 a direct fermentation method to produce glutamate was introduced. The advantages of the fermentation method (eg, reduction of production costs and environmental load) were large enough to cause all glutamate manufacturers to shift to fermentation. Today, total world production of MSG by fermentation is estimated to be 2 million tons/y (2 billion kg/y). However, future production growth will likely require further innovation.

  8. Glutamate oxidation in astrocytes: Roles of glutamate dehydrogenase and aminotransferases

    DEFF Research Database (Denmark)

    McKenna, Mary C; Stridh, Malin H; McNair, Laura Frendrup

    2016-01-01

    The cellular distribution of transporters and enzymes related to glutamate metabolism led to the concept of the glutamate–glutamine cycle. Glutamate is released as a neurotransmitter and taken up primarily by astrocytes ensheathing the synapses. The glutamate carbon skeleton is transferred back t...

  9. Role of Intermediate Filaments in Vesicular Traffic

    Directory of Open Access Journals (Sweden)

    Azzurra Margiotta

    2016-04-01

    Full Text Available Intermediate filaments are an important component of the cellular cytoskeleton. The first established role attributed to intermediate filaments was the mechanical support to cells. However, it is now clear that intermediate filaments have many different roles affecting a variety of other biological functions, such as the organization of microtubules and microfilaments, the regulation of nuclear structure and activity, the control of cell cycle and the regulation of signal transduction pathways. Furthermore, a number of intermediate filament proteins have been involved in the acquisition of tumorigenic properties. Over the last years, a strong involvement of intermediate filament proteins in the regulation of several aspects of intracellular trafficking has strongly emerged. Here, we review the functions of intermediate filaments proteins focusing mainly on the recent knowledge gained from the discovery that intermediate filaments associate with key proteins of the vesicular membrane transport machinery. In particular, we analyze the current understanding of the contribution of intermediate filaments to the endocytic pathway.

  10. Osthole and imperatorin, the active constituents of Cnidium monnieri (L.) Cusson, facilitate glutamate release from rat hippocampal nerve terminals.

    Science.gov (United States)

    Wang, Su-Jane; Lin, Tzu-Yu; Lu, Cheng-Wei; Huang, Wei-Jan

    2008-12-01

    We examined the effects of osthole and imperatorin, two active compounds of Cnidium monnieri (L.) Cusson, on the release of glutamate from rat hippocampal synaptosomes and investigated the possible mechanism. The results showed that osthole or imperatorin significantly facilitated 4-aminopridine (4-AP)-evoked glutamate release in a concentration-dependent manner. The facilitatory action of osthole or imperatorin was blocked by the vesicular transporter inhibitor bafilomycin A1, not by the glutamate transporter inhibitor l-transpyrrolidine-2,4-dicarboxylic acid (l-trans-PDC), indicating that the release facilitation by osthole or imperatorin results from a enhancement of vesicular exocytosis and not from an increase of Ca(2+)-independent efflux via glutamate transporter. Examination of the effect of osthole and imperatorin on cytosolic [Ca(2+)] revealed that the facilitation of glutamate release could be attributed to an increase in voltage-dependent Ca(2+) influx. Consistent with this, omega-conotoxin MVIIC, a wide-spectrum blocker of the N- and P/Q-type Ca(2+) channels, significantly suppressed the osthole or imperatorin-mediated facilitation of glutamate release, but intracellular Ca(2+) release inhibitor dantrolene had no effect. Osthole or imperatorin did not alter the resting synaptosomal membrane potential or 4-AP-mediated depolarization; thus, the facilitation of 4-AP-evoked Ca(2+) influx and glutamate release produced by osthole or imperatorin was not due to it decreasing synaptosomal excitability. In addition, osthole or imperatorin-mediated inhibition of 4-AP-evoked release was prevented by protein kinase C (PKC) inhibitors. Furthermore, osthole or imperatorin increased 4-AP-induced phosphorylation of PKC. Together, these results suggest that osthole or imperatorin effects a facilitation of glutamate release from nerve terminals by positively modulating N-and P/Q-type Ca(2+) channel activation through a signaling cascade involving PKC.

  11. Glucose replaces glutamate as energy substrate to fuel glutamate uptake in glutamate dehydrogenase-deficient astrocytes

    DEFF Research Database (Denmark)

    Pajęcka, Kamilla; Nissen, Jakob D; Stridh, Malin H

    2015-01-01

    -500 µM) in the presence or in the absence of glucose, the metabolism of these substrates was studied by using tritiated glutamate or 2-deoxyglucose as tracers. In addition, the cellular contents of glutamate and ATP were determined. The astrocytes were able to maintain physiological levels of ATP...... of extracellular glutamate independently of the GDH expression level. Moreover, increased intracellular glutamate content was observed in the GDH-deficient cells after a 2-hr incubation in the presence of 100 µM glutamate. It is significant that GDH-deficient cells exhibited an increased utilization of glucose...

  12. Vesicular secretion of auxin: Evidences and implications.

    Science.gov (United States)

    Baluska, Frantisek; Schlicht, Markus; Volkmann, Dieter; Mancuso, Stefano

    2008-04-01

    The plant hormone auxin is secreted in root apices via phospholipase Dzeta2 (PLDzeta2) activity which produces specific population of phosphatidic acid that stimulates secretion of vesicles enriched with auxin. These vesicles were reported to be localized at plant synapses which are active in auxin secretion, especially at the transition zone of the root apex. There are several implications of this vesicular secretion of auxin. In root apices, auxin emerges as plant neurotransmitter-like signal molecule which coordinates activities of adjacent cells via electric and chemical signaling. Putative quantal release of auxin after electrical stimulation, if confirmed, would be part of neuronal communication between plant cells. As auxin transport across plant synapses is tightly linked with integrated sensory perception of environment, especially of omnipresent gravity and light, this process is proposed to mediate the plant perception of environment. These neuronal features allow sessile plants to integrate multitude of sensory signals into the adaptive behavior of whole plants and the animal-like exploratory behavior of growing roots.

  13. Tratamiento actual de la litiasis vesicular Current treatment of vesicular lithiasis

    Directory of Open Access Journals (Sweden)

    Oscar García Rodríguez

    2010-06-01

    Full Text Available El tratamiento quirúrgico de la litiasis vesicular ha cambiado en los últimos años. La incorporación de las nuevas conductas en la práctica médica diaria no siempre es inmediata. Se argumentan las razones relativas a cuándo operar a un paciente con cálculos en la vesícula biliar, y se documenta cómo este procedimiento se reserva fundamentalmente para los pacientes sintomáticos, considerando el dolor como el síntoma por excelencia. También se expone cómo se ha enfrentado este cambio.Surgical treatment of vesicular lithiasis has changed in past years. The addition of the new techniques in daily medical practice not always is immediate. Reasons relative to when to operate a patient presenting with gall bladder calculi are argued and documenting how this procedure is mainly reserved for symptomatic patients where pain is considered as a symptom par excellence . Also, it is exposed how this change has been faced.

  14. Glutamate receptor ligands

    DEFF Research Database (Denmark)

    Guldbrandt, Mette; Johansen, Tommy N; Frydenvang, Karla Andrea

    2002-01-01

    Homologation and substitution on the carbon backbone of (S)-glutamic acid [(S)-Glu, 1], as well as absolute stereochemistry, are structural parameters of key importance for the pharmacological profile of (S)-Glu receptor ligands. We describe a series of methyl-substituted 2-aminoadipic acid (AA.......g., IC(50) = 300 microM for (2R,4S)-4-methyl-AA (5d)]. The two unsaturated analogs (S)- (7a) and (R)-(E)-Delta(4)-5-methyl-AA (7b) turned out to be a weak AMPA receptor agonist and a weak mixed NMDA/AMPA receptor antagonist, respectively....

  15. Tratamiento actual de la litiasis vesicular Current treatment of vesicular lithiasis

    OpenAIRE

    Oscar García Rodríguez

    2010-01-01

    El tratamiento quirúrgico de la litiasis vesicular ha cambiado en los últimos años. La incorporación de las nuevas conductas en la práctica médica diaria no siempre es inmediata. Se argumentan las razones relativas a cuándo operar a un paciente con cálculos en la vesícula biliar, y se documenta cómo este procedimiento se reserva fundamentalmente para los pacientes sintomáticos, considerando el dolor como el síntoma por excelencia. También se expone cómo se ha enfrentado este cambio.Surgical t...

  16. Substrate and Cation Binding Mechanism of Glutamate Transporter Homologs

    NARCIS (Netherlands)

    Jensen, Sonja

    2017-01-01

    Glutamate transporters and their homologs are membrane proteins that transport glutamate and aspartate together with sodium ions and/or protons. Human glutamate transporters remove the neurotransmitter glutamate after signal transmission. Therefore, glutamate transporters play a great role in

  17. Stochastic Model of Maturation and Vesicular Exchange in Cellular Organelles

    CERN Document Server

    Vagne, Quentin

    2016-01-01

    The dynamical organization of membrane-bound organelles along intracellular transport pathways relies on vesicular exchange between organelles and on biochemical maturation of the organelle content by specific enzymes. The relative importance of each mechanism in controlling organelle dynamics remains controversial, in particular for transport through the Golgi apparatus. Using a stochastic model, we show that full maturation of membrane-bound compartments can be seen as the stochastic escape from a steady-state in which export is dominated by vesicular exchange. We show that full maturation can contribute a significant fraction of the total out-flux for small organelles such as endosomes and Golgi cisternae.

  18. Enhancement of absorption and hepatoprotective potential through soya-phosphatidylcholine-andrographolide vesicular system.

    Science.gov (United States)

    Jain, Pushpendra Kumar; Khurana, Navneet; Pounikar, Yogesh; Gajbhiye, Asmita; Kharya, Murli Dhar

    2013-06-01

    Andrographis paniculata is a medicinal herb used extensively for various ailments and contains therapeutically active phytoconstituent, andrographolide (AN). Although hepatoprotective activity of AN is established, but their bioavailability is restricted due to its rapid clearance. The aim of this study, therefore, was to formulate AN herbosomes (ANH) through complexation with naturally occurring soya-phosphatidylcholine (SPC), in order to enhance absorption. Prepared andrographolide-soy phosphatidylcholine (AN-SPC) complex prepared was subjected for characterisation of complex and formation of vesicular system known as ANH using rotary evaporation techniques. This complex was subjected to in vitro study using everted small intestine sac technique which showed significantly increased absorption of AN from the ANH as compared to the plain AN. The hepatoprotective potential of ANH and plain AN was evaluated using carbon tetrachloride inducing hepatotoxicity rat model and compared, in which ANH equivalent to 50 mg/kg of plain AN significantly restore serum glutamate oxalacetate transaminase (112.4 ± 9.67 for AN whereas 90.2 ± 4.23 for ANH) and serum glutamate pyruvate transaminase (109.3 ± 7.89 for AN whereas 90.6 ± 4.34 for ANH) level as compared to control group. The ANH showed significantly better absorption than plain AN and this effect of ANH was also comparable to the standard drug (Silymarin). The findings of present study reveal that ANH has better bioavailability as shown by in vitro absorption study and hence improved hepatoprotection as compared to plain AN at equivalent dose.

  19. Depolarization by K*O+ and glutamate activates different neurotransmitter release mechanisms in gabaergic neurons: vesicular versus non-vesicular release of gaba

    DEFF Research Database (Denmark)

    Belhage, Bo; Hansen, G.H.; Schousboe, Arne

    1993-01-01

    Neurotransmitter release, gaba release, membrane transporter, vesicles, intracellular CA*OH, neuron cultures......Neurotransmitter release, gaba release, membrane transporter, vesicles, intracellular CA*OH, neuron cultures...

  20. Vesicular signalling and immune modulation as hedonic fingerprints

    DEFF Research Database (Denmark)

    Bisgaard, Christina F; Bak, Steffen; Christensen, Trine

    2012-01-01

    ) differential gel electrophoresis (DIGE) and tandem mass spectrometry (MS/MS). The majority of the proteins we identified were enzymes involved in different metabolic activities. Additional proteins were functionally classified as vesicular proteins and immune system proteins. Rab GDP dissociation inhibitor...

  1. Formulation and evaluation of a transfersomal vesicular carrier ...

    African Journals Online (AJOL)

    AF1 was investigated. NIPRD-AF1 is a phytomedicine derived from the leaves of an indigenous plant, for use in the treatment of fungal infections. A transfersomal vesicular carrier system of NIPRD-AF1 was formulated and evaluated for topical ...

  2. Effect of vesicular arbuscular mycorrhizal fungus on the ...

    African Journals Online (AJOL)

    The symbiotic association between certain plants and microorganisms plays an important role in soil fertilization, and improves their growth and mineral nutrition. The symbiotic association between vesicular arbuscular mycorrhizal (VAM) fungi and roots provides a significant contribution to plant nutrition and growth.

  3. Renal epithelial cells can release ATP by vesicular fusion

    Directory of Open Access Journals (Sweden)

    Randi G Bjaelde

    2013-09-01

    Full Text Available Renal epithelial cells have the ability to release nucleotides as paracrine factors. In the intercalated cells of the collecting duct, ATP is released by connexin30 (cx30, which is selectively expressed in this cell type. However, ATP is released by virtually all renal epithelia and the aim of the present study was to identify possible alternative nucleotide release pathways in a renal epithelial cell model. We used MDCK (type1 cells to screen for various potential ATP release pathways. In these cells, inhibition of the vesicular H+-ATPases (bafilomycin reduced both the spontaneous and hypotonically (80%-induced nucleotide release. Interference with vesicular fusion using N-ethylamide markedly reduced the spontaneous nucleotide release, as did interference with trafficking from the endoplasmic reticulum to the Golgi apparatus (brefeldin A1 and vesicular transport (nocodazole. These findings were substantiated using a siRNA directed against SNAP-23, which significantly reduced spontaneous ATP release. Inhibition of pannexin and connexins did not affect the spontaneous ATP release in this cell type, which consists of ∼90% principal cells. TIRF-microscopy of either fluorescently-labeled ATP (MANT-ATP or quinacrine-loaded vesicles, revealed that spontaneous release of single vesicles could be promoted by either hypoosmolality (50% or ionomycin. This vesicular release decreased the overall cellular fluorescence by 5.8% and 7.6% respectively. In summary, this study supports the notion that spontaneous and induced ATP release can occur via exocytosis in renal epithelial cells.

  4. The vesicular-arbuscular mycorrhizal symbiosis | Quilambo | African ...

    African Journals Online (AJOL)

    Vesicular-arbuscular mycorrhiza fungi are associated with the majority ot the terrestrial plants. Their function ranges from stress alleviation to bioremediation in soils polluted with heavy metals. However, our knowledge about this symbiosis is still limited. For the semi-arid tropics, where some african countries are located, ...

  5. Influence of vesicular arbuscular mycorrhiza (VAM) and phosphate ...

    African Journals Online (AJOL)

    A field experiment was carried out to find out the effect of biofertilizers, vesicular arbuscular mycorrhiza (VAM), and phosphate solubilising bacteria (PSB) individually and in combination on growth and physiological attributing properties of Marsdenia volubilis plant under nursery conditions. The plant seedlings were ...

  6. Glutamic acid as anticancer agent: An overview.

    Science.gov (United States)

    Dutta, Satyajit; Ray, Supratim; Nagarajan, K

    2013-10-01

    The objective of the article is to highlight various roles of glutamic acid like endogenic anticancer agent, conjugates to anticancer agents, and derivatives of glutamic acid as possible anticancer agents. Besides these emphases are given especially for two endogenous derivatives of glutamic acid such as glutamine and glutamate. Glutamine is a derivative of glutamic acid and is formed in the body from glutamic acid and ammonia in an energy requiring reaction catalyzed by glutamine synthase. It also possesses anticancer activity. So the transportation and metabolism of glutamine are also discussed for better understanding the role of glutamic acid. Glutamates are the carboxylate anions and salts of glutamic acid. Here the roles of various enzymes required for the metabolism of glutamates are also discussed.

  7. 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

  8. [The glutamate hypothesis of schizophrenia].

    Science.gov (United States)

    Hasan, A; Malchow, B; Falkai, P; Schmitt, A

    2014-08-01

    For many years, the dopamine hypothesis of schizophrenia has been the leading theory explaining the aetiology of schizophrenia. However, since the first observation showed that NMDA-receptor antagonists (e. g., PCP) can induce all kinds of schizophrenia symptoms in humans, the glutamate hypothesis of schizophrenia has been established as an additional explanation model. Apart from the PCP-induced psychoses, many other findings from all areas of modern neuroscience have confirmed and extended the glutamate hypothesis. This review discusses the available evidence for the glutamate hypothesis and puts the different findings into relation. Consecutively, the possibilities for a pharmacological modulation of the glutamate system and recent clinical trials are discussed. To sum up, one could note that the glutamate hypothesis of schizophrenia is now well-established. The development of glutamatergic antipsychotics is still in the early stages, but there is hope for a new generation of antipsychotics based on the glutamate hypothesis of schizophrenia. However, recent findings from registration trials could not provide positive findings for the recently developed glutamatergic drugs. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Metabotropic glutamate receptors in cancer.

    Science.gov (United States)

    Yu, Lumeng J; Wall, Brian A; Wangari-Talbot, Janet; Chen, Suzie

    2017-03-15

    Metabotropic glutamate receptors (mGluRs) are widely known for their roles in synaptic signaling. However, accumulating evidence suggests roles of mGluRs in human malignancies in addition to synaptic transmission. Somatic cell homeostasis presents intriguing possibilities of mGluRs and glutamate signaling as novel targets for human cancers. More recently, aberrant glutamate signaling has been shown to participate in the transformation and maintenance of various cancer types, including glioma, melanoma skin cancer, breast cancer, and prostate cancer, indicating that genes encoding mGluRs, GRMs, can function as oncogenes. Here, we provide a review on the interactions of mGluRs and their ligand, glutamate, in processes that promote the growth of tumors of neuronal and non-neuronal origins. Further, we discuss the evolution of riluzole, a glutamate release inhibitor approved for amyotrophic lateral sclerosis (ALS), but now fashioned as an mGluR1 inhibitor for melanoma therapy and as a radio-sensitizer for tumors that have metastasized to the brain. With the success of riluzole, it is not far-fetched to believe that other drugs that may act directly or indirectly on other mGluRs can be beneficial for multiple applications. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Genotoxicity of monosodium glutamate.

    Science.gov (United States)

    Ataseven, Nazmiye; Yüzbaşıoğlu, Deniz; Keskin, Ayten Çelebi; Ünal, Fatma

    2016-05-01

    Monosodium glutamate (MSG) is one of the most widely used flavor enhancers throughout the world. The aim of this study is to investigate the genotoxic potential of MSG by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), cytokinesis-blocked micronucleus (CBMN), and random amplified polymorphic DNA-polimerase chain reaction (RAPD-PCR) in cultured human lymphocytes and alkaline comet assays in isolated human lymphocytes, which were incubated with six concentrations (250, 500, 1000, 2000, 4000 and 8000 μg/mL) of MSG. The result of this study indicated that MSG significantly and dose dependently increased the frequencies of CAs, SCE and MN in all treatments and times, compared with control. However, the replication (RI) and nuclear division indices (NDI) were not affected. In this paper, in vitro genotoxic effects of the MSG was also investigated on human peripheral lymphocytes by analysing the RAPD-PCR with arbitrary 10-mer primers. The changes occurring in RAPD profiles after MSG treatment include increase or decrease in band intensity and gain or loss of bands. In the comet assay, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1-h in vitro exposure. Our results demonstrate that MSG is genotoxic to the human peripheral blood lymphocytes in vitro. Copyright © 2016. Published by Elsevier Ltd.

  11. Curcumin inhibits glutamate release in nerve terminals from rat prefrontal cortex: possible relevance to its antidepressant mechanism.

    Science.gov (United States)

    Lin, Tzu Yu; Lu, Cheng Wei; Wang, Chia-Chuan; Wang, Ying-Chou; Wang, Su-Jane

    2011-08-15

    There is abundant evidence suggesting the relevance of glutamate to depression and antidepressant mechanisms. Curcumin, a major active compound of Curcuma longa, has been reported to have the biological function of antidepressant. The aim of the present study was to investigate the effect of curcumin on endogenous glutamate release in nerve terminals of rat prefrontal cortex and the underlying mechanisms. The results showed that curcumin inhibited the release of glutamate that was evoked by exposing synaptosomes to the K(+) channel blocker 4-aminopyridine (4-AP). This phenomenon was blocked by the chelating the extracellular Ca(2+) ions, and by the vesicular transporter inhibitor bafilomycin A1, but was insensitive to the glutamate transporter inhibitor DL-threo-β-benzyl-oxyaspartate (DL-TBOA). Further experiments demonstrated that curcumin decreased depolarization-induced increase in [Ca(2+)](C), whereas it did not alter the resting membrane potential or 4-AP-mediated depolarization. Furthermore, the inhibitory effect of curcumin on evoked glutamate release was prevented by blocking the Ca(v)2.2 (N-type) and Ca(v)2.1 (P/Q-type) channels, but not by blocking intracellular Ca(2+) release or Na(+)/Ca(2+) exchange. These results suggest that curcumin inhibits evoked glutamate release from rat prefrontocortical synaptosomes by the suppression of presynaptic Ca(v)2.2 and Ca(v)2.1 channels. Additionally, we also found that the inhibitory effect of curcumin on 4-AP-evoked glutamate release was completely abolished by the clinically effective antidepressant fluoxetine. This suggests that curcumin and fluoxetine use a common intracellular mechanism to inhibit glutamate release from rat prefrontal cortex nerve terminals. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Group I Metabotropic Glutamate Receptors

    DEFF Research Database (Denmark)

    Erichsen, Julie Ladeby; Blaabjerg, Morten; Bogetofte Thomasen, Helle

    2015-01-01

    differentiated an immortalized, forebrain-derived stem cell line in the presence or absence of glutamate and with addition of either the group I mGluR agonist DHPG or the selective antagonists; MPEP (mGluR5) and LY367385 (mGluR1). Characterization of differentiated cells revealed that both mGluR1 and mGluR5 were...... present on the cells. Addition of glutamate to the growth medium significantly increased cell proliferation and reduced cell death, resulting in increased cell numbers. In the presence of glutamate, selective activation of group I mGluRs reduced gliogenesis, whereas selective inhibition of group I m...... is, however, needed to realise their therapeutic potential. Glutamate and group I metabotropic glutamate receptors (mGluRs) affect proliferation and survival of rodent NSCs both during embryonic and postnatal development. To investigate the role of group I mGluRs (mGluR1 and mGluR5) on human NSCs, we...

  13. [Vesicular and pronuclear glycoproteins in the pathogenesis of cholesterol lithiasis].

    Science.gov (United States)

    Jirsa, M; Smíd, F; Marecek, Z

    1998-01-26

    Several biliary proteins have been known to accelerate fusion of cholesterol rich phospholipid vesicles. Some of them are present in vesicular membrane, localisation of other proteins is unknown. Biliary glycoprotein has not been studied in consequence with pathogenesis of cholesterol lithiasis. Low molecular extravesicular proteins were separated from vesicles by gel filtration on a 1200mm column of Sephacryl S-300 HR. Immunoglobulins IgM, IgA, haptoglobin, biliary glycoprotein I (BGP I) and nonspecific crossreactive antigen were eluted along with vesicles. Albumin and alpha 1-acid glycoprotein were eluted later and must be extravesicular. Fact that BGP I (85 kDa membrane glycoprotein) eluted along with vesicles and not in albumin fraction suggests that it might be bound in vesicular membrane. As a known adhesion molecule it could thus play an important role in pathogenesis of cholesterol cholelithiasis.

  14. Expression of Vesicular Nucleotide Transporter in Rat Odontoblasts

    OpenAIRE

    Ikeda, Erina; Goto, Tetsuya; Gunjigake, Kaori; Kuroishi, Kayoko; Ueda, Masae; Kataoka, Shinji; Toyono, Takashi; Nakatomi, Mitsushiro; Seta, Yuji; Kitamura, Chiaki; Nishihara, Tatsuji; Kawamoto, Tatsuo

    2016-01-01

    Several theories have been proposed regarding pain transmission mechanisms in tooth. However, the exact signaling mechanism from odontoblasts to pulp nerves remains to be clarified. Recently, ATP-associated pain transmission has been reported, but it is unclear whether ATP is involved in tooth pain transmission. In the present study, we focused on the vesicular nucleotide transporter (VNUT), a transporter of ATP into vesicles, and examined whether VNUT was involved in ATP release from odontob...

  15. Understanding and altering cell tropism of vesicular stomatitis virus

    OpenAIRE

    Hastie, Eric; Cataldi, Marcela; Marriott, Ian; Valery Z Grdzelishvili

    2013-01-01

    Vesicular stomatitis virus (VSV) is a prototypic nonsegmented negative-strand RNA virus. VSV’s broad cell tropism makes it a popular model virus for many basic research applications. In addition, a lack of preexisting human immunity against VSV, inherent oncotropism and other features make VSV a widely used platform for vaccine and oncolytic vectors. However, VSV’s neurotropism that can result in viral encephalitis in experimental animals needs to be addressed for the use of the virus as a sa...

  16. Influenza infection modulates vesicular trafficking and induces Golgi complex disruption.

    Science.gov (United States)

    Yadav, Vibha; Panganiban, Antonito T; Honer Zu Bentrup, Kerstin; Voss, Thomas G

    2016-12-01

    Influenza A virus (IFV) replicates its genome in the nucleus of infected cells and uses the cellular protein transport system for genome trafficking from the nucleus to the plasma membrane. However, many details of the mechanism of this process, and its relationship to subsequent cytoplasmic virus trafficking, have not been elucidated. We examined the effect of nuclear transport inhibitors Leptomycin B (LB), 5,6 dichloro-1-β-d-ribofuranosyl-benzimidazole (DRB), the vesicular transport inhibitor Brefeldin A (BFA), the caspase inhibitor ZWEHD, and microtubule inhibitor Nocodazole (NOC) on virus replication and intracellular trafficking of viral nucleoprotein (NP) from the nucleus to the ER and Golgi. Also, we carried out complementary studies to determine the effect of IFV on intracellular membranes. Inhibition of the CRM1 and TAP-P15 nuclear transport pathways by DRB and LB blocked completely the export of virus. Inhibition of vesicular trafficking by BFA, NOC, and ZWEHD also affected influenza infection. Interestingly, IFV infection induced fragmentation of the Golgi complex resulting in diffuse distribution of large and small vesicles throughout the cytoplasm. Live-cell microscopy revealed expansion of Golgi localization signals indicating progressive dispersion of Golgi positive structures, resulting in the disassembly of the Golgi ribbon structure. Other vesicular components (Rab1b, ARF1 and GBF1) were also found to be required for IFV infection. Furthermore, the exact step at which IFV infection disrupts vesicle trafficking was identified as the ER-Golgi intermediate compartment. These findings suggest that IFV NP is trafficked from the nucleus via the CRM1 and TAP pathways. IFV modulates vesicular trafficking inducing disruption of the Golgi complex. These studies provide insight on the ways in which IFV affects intracellular trafficking of different host proteins and will facilitate identification of useful pharmaceutical targets to abrogate virus

  17. VGluT2 expression in painful Achilles and patellar tendinosis: evidence of local glutamate release by tenocytes

    Science.gov (United States)

    Scott, Alexander; Alfredson, Håkan; Forsgren, Sture

    2014-01-01

    SUMMARY BACKGROUND The pathogenesis of chronic tendinopathy is unclear. We have previously measured high intratendinous levels of glutamate in patients with tendinosis, suggesting potential roles of glutamate in the modulation of pain, vascular function, and degenerative changes including apoptosis of tenocytes. However, the origin of free glutamate found in tendon tissue is completely unknown. METHODS Surgical biopsies of pain-free normal tendons and tendinosis tendons (Achilles and patellar) were examined immunohistochemically using antibodies against vesicular glutamate transporters (VGluT1 and VGluT2), as indirect markers of glutamate release. In situ hybridization for VGluT2 mRNA was also conducted. RESULTS Specific immunoreactions for VGluT2, but not VGluT1, could be consistently detected in tenocytes. However, there were interindividual variations in the levels of immunoreactivity. The level of immunoreaction for VGluT2 was higher in tendinosis tendons compared to normal tendon (ptendinosis, including tenocyte proliferation and apoptosis, extracellular matrix metabolism, nociception and blood flow. PMID:18050306

  18. Modeling of glutamate-induced dynamical patterns

    DEFF Research Database (Denmark)

    Faurby-Bentzen, Christian Krefeld; Zhabotinsky, A.M.; Laugesen, Jakob Lund

    2009-01-01

    Based on established physiological mechanisms, the paper presents a detailed computer model, which supports the hypothesis that temporal lobe epilepsy may be caused by failure of glutamate reuptake from the extracellular space. The elevated glutamate concentration causes an increased activation...

  19. Glutamate Metabolism in Major Depressive Disorder

    National Research Council Canada - National Science Library

    Abdallah, Chadi G; Jiang, Lihong; De Feyter, Henk M; Fasula, Madonna; Krystal, John H; Rothman, Douglas L; Mason, Graeme F; Sanacora, Gerard

    2014-01-01

    Research on novel treatments for major depressive disorder focuses quite deeply on glutamate function, and this research would benefit from a brain-imaging technique that precisely quantified glutamate function...

  20. DNA nanopore translocation in glutamate solutions

    NARCIS (Netherlands)

    Plesa, C.; Van Loo, N.; Dekker, C.

    2015-01-01

    Nanopore experiments have traditionally been carried out with chloride-based solutions. Here we introduce silver/silver-glutamate-based electrochemistry as an alternative, and study the viscosity, conductivity, and nanopore translocation characteristics of potassium-, sodium-, and lithium-glutamate

  1. Glutamic acid as anticancer agent: An overview

    National Research Council Canada - National Science Library

    Dutta, Satyajit; Ray, Supratim; Nagarajan, K

    2013-01-01

    The objective of the article is to highlight various roles of glutamic acid like endogenic anticancer agent, conjugates to anticancer agents, and derivatives of glutamic acid as possible anticancer agents...

  2. 21 CFR 182.1045 - Glutamic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Glutamic acid. 182.1045 Section 182.1045 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN....1045 Glutamic acid. (a) Product. Glutamic acid. (b) [Reserved] (c) Limitations, restrictions, or...

  3. [Glutamate signaling and neural plasticity].

    Science.gov (United States)

    Watanabe, Masahiko

    2013-07-01

    Proper functioning of the nervous system relies on the precise formation of neural circuits during development. At birth, neurons have redundant synaptic connections not only to their proper targets but also to other neighboring cells. Then, functional neural circuits are formed during early postnatal development by the selective strengthening of necessary synapses and weakening of surplus connections. Synaptic connections are also modified so that projection fields of active afferents expand at the expense of lesser ones. We have studied the molecular mechanisms underlying these activity-dependent prunings and the plasticity of synaptic circuitry using gene-engineered mice defective in the glutamatergic signaling system. NMDA-type glutamate receptors are critically involved in the establishment of the somatosensory pathway ascending from the brainstem trigeminal nucleus to the somatosensory cortex. Without NMDA receptors, whisker-related patterning fails to develop, whereas lesion-induced plasticity occurs normally during the critical period. In contrast, mice lacking the glutamate transporters GLAST or GLT1 are selectively impaired in the lesion-induced critical plasticity of cortical barrels, although whisker-related patterning itself develops normally. In the developing cerebellum, multiple climbing fibers initially innervating given Purkinje cells are eliminated one by one until mono-innervation is achieved. In this pruning process, P/Q-type Ca2+ channels expressed on Purkinje cells are critically involved by the selective strengthening of single main climbing fibers against other lesser afferents. Therefore, the activation of glutamate receptors that leads to an activity-dependent increase in the intracellular Ca2+ concentration plays a key role in the pruning of immature synaptic circuits into functional circuits. On the other hand, glutamate transporters appear to control activity-dependent plasticity among afferent fields, presumably through adjusting

  4. Vesicular exanthema of swine virus: isolation and serotyping of field samples.

    OpenAIRE

    Edwards, J F; Yedloutschnig, R J; Dardiri, A H; Callis, J. J.

    1987-01-01

    Virus isolation was attempted from 262 field samples of vesicular material collected during the outbreaks of vesicular exanthema of swine in the U.S.A. from 1952-54. Using primary swine kidney culture, viral cytopathogenic agents were isolated from 76.3% of the samples. However, an overall recovery rate of 82.1% was obtained after samples negative in tissue culture were inoculated intradermally in susceptible swine. All vesicular exanthema of swine virus isolates were identified as serotype B...

  5. The glutamate/GABA-glutamine cycle

    DEFF Research Database (Denmark)

    Bak, Lasse K; Schousboe, Arne; Waagepetersen, Helle S

    2006-01-01

    Neurons are metabolically handicapped in the sense that they are not able to perform de novo synthesis of neurotransmitter glutamate and gamma-aminobutyric acid (GABA) from glucose. A metabolite shuttle known as the glutamate/GABA-glutamine cycle describes the release of neurotransmitter glutamate...... or GABA from neurons and subsequent uptake into astrocytes. In return, astrocytes release glutamine to be taken up into neurons for use as neurotransmitter precursor. In this review, the basic properties of the glutamate/GABA-glutamine cycle will be discussed, including aspects of transport and metabolism....... Discussions of stoichiometry, the relative role of glutamate vs. GABA and pathological conditions affecting the glutamate/GABA-glutamine cycling are presented. Furthermore, a section is devoted to the accompanying ammonia homeostasis of the glutamate/GABA-glutamine cycle, examining the possible means...

  6. Endobronchial tuberculosis presented as multiple endobronchial vesicular lesions

    Directory of Open Access Journals (Sweden)

    Farah Idrees

    2015-01-01

    Full Text Available Endobronchial tuberculosis (EBTB is a tuberculous infection of the tracheobronchial tree with microbiological and histopathological evidence, with or without parenchymal involvement. EBTB commonly presents as acute or insidious onset cough, wheeze, low grade fever, and constitutional symptoms. In elderly patients, other differentials like malignancy and pneumonia may lead to misdiagnosis. Hence, bronchoscopy is essential for confirmation of EBTB. Here we report a rare presentation of EBTB in a 65 year old patient who presented with 3 months history of fever and cough and have multiple endobronchial vesicular lesions on bronchoscopy.

  7. Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops

    DEFF Research Database (Denmark)

    Jakobsen, Iver

    1986-01-01

    The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm...... in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard...

  8. Vesicular disease in 9-week-old pigs experimentally infected with Senecavirus A

    Science.gov (United States)

    Introduction: Senecavirus A (SVA), a picornavirus, has been infrequently associated with cases of idiopathic vesicular disease (IVD) in pigs in the US and Canada since 1988. In 2014 and 2015 there was surge of IVD cases in Brazil and US, respectively. SVA was identified in serum, vesicular fluid, an...

  9. H-aggregation of azobenzene-substituted amphiphiles in vesicular membranes

    NARCIS (Netherlands)

    Kuiper, JM; Engberts, JBFN

    2004-01-01

    Photochemical switching has been studied of double-tailed phosphate amphiphiles containing azobenzene units in both tails in aqueous vesicular dispersions and in mixed vesicular systems with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). Since the ease of switching depends on the strength of the

  10. Introduction to the Glutamate-Glutamine Cycle

    DEFF Research Database (Denmark)

    Sonnewald, Ursula; Schousboe, Arne

    2016-01-01

    The term 'glutamate-glutamine cycle' was coined several decades ago based on the observation that using certain (14)C-labeled precursors for studies of brain metabolism the specific radioactivity of glutamine generated from glutamate was higher than that of glutamate, its immediate precursor....... This is metabolically impossible unless it is assumed that at least two distinct pools of these amino acids exist. This combined with the finding that the enzyme synthesizing glutamine from glutamate was expressed in astrocytes but not in neurons formed the basis of the notion that a cycle must exist in which glutamate...... released from neurons is transported into astrocytes, converted to glutamine which is subsequently returned to neurons and converted to glutamate by an enzyme the activity of which is much higher in neurons than in astrocytes. Originally this cycle was supposed to function in a stoichiometric fashion...

  11. Introduction to the Glutamate-Glutamine Cycle

    DEFF Research Database (Denmark)

    Sonnewald, Ursula; Schousboe, Arne

    2016-01-01

    . This is metabolically impossible unless it is assumed that at least two distinct pools of these amino acids exist. This combined with the finding that the enzyme synthesizing glutamine from glutamate was expressed in astrocytes but not in neurons formed the basis of the notion that a cycle must exist in which glutamate......The term 'glutamate-glutamine cycle' was coined several decades ago based on the observation that using certain (14)C-labeled precursors for studies of brain metabolism the specific radioactivity of glutamine generated from glutamate was higher than that of glutamate, its immediate precursor...... released from neurons is transported into astrocytes, converted to glutamine which is subsequently returned to neurons and converted to glutamate by an enzyme the activity of which is much higher in neurons than in astrocytes. Originally this cycle was supposed to function in a stoichiometric fashion...

  12. The amino acid transporters of the glutamate/GABA-glutamine cycle and their impact on insulin and glucagon secretion

    Directory of Open Access Journals (Sweden)

    Monica eJenstad

    2013-12-01

    Full Text Available Intercellular communication is pivotal in optimising and synchronising cellular responses to keep internal homeostasis and to respond adequately to external stimuli. In the central nervous system (CNS, glutamatergic and GABAergic signals are postulated to be dependent on the glutamate/GABA-glutamine (GGG cycle for vesicular loading of neurotransmitters, for inactivating the signal and for the replenishment of the neurotransmitters. Islets of Langerhans release the hormones insulin and glucagon, but share similarities with CNS cells in for example transcriptional control of development and differentiation, and chromatin methylation. Interestingly, proteins involved in the CNS in secretion of the neurotransmitters and emitting their responses as well as the regulation of these processes, are also found in islet cells. Moreover, high levels of glutamate, GABA and glutamine and their respective vesicular and plasma membrane transporters have been shown in the islet cells and there is emerging support for these amino acids and their transporters playing important roles in the maturation and secretion of insulin and glucagon. In this review, we will discuss the feasibility of recent data in the field in relation to the biophysical properties of the transporters (Slc1, Slc17, Slc32 and Slc38 and physiology of hormone secretion in islets of Langerhans.

  13. Genetics Home Reference: glutamate formiminotransferase deficiency

    Science.gov (United States)

    ... are some genetic conditions more common in particular ethnic groups? Genetic Changes Mutations in the FTCD gene cause glutamate formiminotransferase deficiency . The FTCD gene provides instructions for ...

  14. AMPK Activation Affects Glutamate Metabolism in Astrocytes

    DEFF Research Database (Denmark)

    Voss, Caroline Marie; Pajęcka, Kamilla; Stridh, Malin H

    2015-01-01

    acid (TCA) cycle was studied using high-performance liquid chromatography analysis supplemented with gas chromatography-mass spectrometry technology. It was found that AMPK activation had profound effects on the pathways involved in glutamate metabolism since the entrance of the glutamate carbon...... affected by a reduction of the flux of glutamate derived carbon through the malic enzyme and pyruvate carboxylase catalyzed reactions. Finally, it was found that in the presence of glutamate as an additional substrate, glucose metabolism monitored by the use of tritiated deoxyglucose was unaffected by AMPK...

  15. Glutamate signalling in healthy and diseased bone

    Directory of Open Access Journals (Sweden)

    Robert W. Cowan

    2012-07-01

    Full Text Available Bone relies on multiple extracellular signalling systems to maintain homeostasis of its normal structure and functions. The amino acid glutamate is a fundamental extracellular messenger molecule in many tissues, and is used in bone for both neural and non-neural signalling. This review focuses on the non-neural interactions, and examines the evolutionarily ancient glutamate signalling system in the context of its application to normal bone functioning and discusses recent findings on the role of glutamate signalling as they pertain to maintaining healthy bone structure. The underlying mechanisms of glutamate signalling and the many roles glutamate plays in modulating bone physiology are featured, including those involved in osteoclast and osteoblast differentiation and mature cell functions. Moreover, the relevance of glutamate signalling systems in diseases that affect bone, such as cancer and rheumatoid arthritis, is discussed, and will highlight how the glutamate system may be exploited as a viable therapeutic target. We will identify novel areas of research where knowledge of glutamate communication mechanisms may aid in our understanding of the complex nature of bone homeostasis. By uncovering the contributions of glutamate in maintaining healthy bone, the reader will discover how this complex molecular signalling system may advance our capacity to treat bone pathologies.

  16. A putative vesicular transporter expressed in Drosophila mushroom bodies that mediates sexual behavior may define a novel neurotransmitter system

    OpenAIRE

    Brooks, Elizabeth S.; Greer, Christina L.; Romero-Calderón, Rafael; Serway, Christine N.; Grygoruk, Anna; Haimovitz, Jasmine M.; Bac T. Nguyen; Najibi, Rod; Tabone, Christopher J; de Belle, J. Steven; Krantz, David E.

    2011-01-01

    Storage and release of classical and amino acid neurotransmitters requires vesicular transporters. Some neurons lack known vesicular transporters, suggesting additional neurotransmitter systems remain unidentified. Insect mushroom bodies (MBs) are critical for several behaviors, including learning, but the neurotransmitters released by the intrinsic Kenyon cells (KCs) remain unknown. Likewise, KCs do not express a known vesicular transporter. We report the identification of a novel Drosophila...

  17. Prefrontal changes in the glutamate-glutamine cycle and neuronal/glial glutamate transporters in depression with and without suicide

    NARCIS (Netherlands)

    Zhao, J; Verwer, R W H; van Wamelen, D J; Qi, X-R; Gao, S-F; Lucassen, P J; Swaab, D F

    2016-01-01

    There are indications for changes in glutamate metabolism in relation to depression or suicide. The glutamate-glutamine cycle and neuronal/glial glutamate transporters mediate the uptake of the glutamate and glutamine. The expression of various components of the glutamate-glutamine cycle and the

  18. A new role for human dyskerin in vesicular trafficking.

    Science.gov (United States)

    Di Maio, Nunzia; Vicidomini, Rosario; Angrisani, Alberto; Belli, Valentina; Furia, Maria; Turano, Mimmo

    2017-10-01

    Dyskerin is an essential, conserved, multifunctional protein found in the nucleolus, whose loss of function causes the rare genetic diseases X-linked dyskeratosis congenita and Hoyeraal-Hreidarsson syndrome. To further investigate the wide range of dyskerin's biological roles, we set up stable cell lines able to trigger inducible protein knockdown and allow a detailed analysis of the cascade of events occurring within a short time frame. We report that dyskerin depletion quickly induces cytoskeleton remodeling and significant alterations in endocytic Ras-related protein Rab-5A/Rab11 trafficking. These effects arise in different cell lines well before the onset of telomere shortening, which is widely considered the main cause of dyskerin-related diseases. Given that vesicular trafficking affects many homeostatic and differentiative processes, these findings add novel insights into the molecular mechanisms underlining the pleiotropic manifestation of the dyskerin loss-of-function phenotype.

  19. Glutamate gated spiking Neuron Model.

    Science.gov (United States)

    Deka, Krisha M; Roy, Soumik

    2014-01-01

    Biological neuron models mainly analyze the behavior of neural networks. Neurons are described in terms of firing rates viz an analog signal. The Izhikevich neuron model is an efficient, powerful model of spiking neuron. This model is a reduction of Hodgkin-Huxley model to a two variable system and is capable of producing rich firing patterns for many biological neurons. In this paper, the Regular Spiking (RS) neuron firing pattern is used to simulate the spiking of Glutamate gated postsynaptic membrane. Simulation is done in MATLAB environment for excitatory action of synapses. Analogous simulation of spiking of excitatory postsynaptic membrane potential is obtained.

  20. Some Properties of Glutamate Dehydrogenase from the Marine Red ...

    African Journals Online (AJOL)

    Daisy Ouya

    1) glutamate dehydrogenases (GDH) and (2) glutamine synthetase (GS)/ glutamate synthase (GOGAT). In the GS/ GOGAT route, ammonia is first incorporated into glutamine by the action of GS and subsequently into glutamic acid by GOGAT.

  1. Vesicular nucleotide transporter (VNUT): appearance of an actress on the stage of purinergic signaling.

    Science.gov (United States)

    Moriyama, Yoshinori; Hiasa, Miki; Sakamoto, Shohei; Omote, Hiroshi; Nomura, Masatoshi

    2017-06-14

    Vesicular storage of ATP is one of the processes initiating purinergic chemical transmission. Although an active transport mechanism was postulated to be involved in the processes, a transporter(s) responsible for the vesicular storage of ATP remained unidentified for some time. In 2008, SLC17A9, the last identified member of the solute carrier 17 type I inorganic phosphate transporter family, was found to encode the vesicular nucleotide transporter (VNUT) that is responsible for the vesicular storage of ATP. VNUT transports various nucleotides in a membrane potential-dependent fashion and is expressed in the various ATP-secreting cells. Mice with knockout of the VNUT gene lose vesicular storage and release of ATP from neurons and neuroendocrine cells, resulting in blockage of the initiation of purinergic chemical transmission. Thus, VNUT plays an essential role in the vesicular storage and release of ATP. The VNUT knockout mice exhibit resistance for neuropathic pain and a therapeutic effect against diabetes by way of increased insulin sensitivity. Thus, VNUT inhibitors and suppression of VNUT gene expression may be used for therapeutic purposes through suppression of purinergic chemical transmission. This review summarizes the studies to date on VNUT and discusses what we have learned about the relevance of vesicular ATP release as a potential drug target.

  2. Activity of the lactate-alanine shuttle is independent of glutamate-glutamine cycle activity in cerebellar neuronal-astrocytic cultures

    DEFF Research Database (Denmark)

    Bak, Lasse K; Sickmann, Helle M; Schousboe, Arne

    2004-01-01

    The glutamate-glutamine cycle describes the neuronal release of glutamate into the synaptic cleft, astrocytic uptake, and conversion into glutamine, followed by release for use as a neuronal glutamate precursor. This only explains the fate of the carbon atoms, however, and not that of the ammonia...... and corresponding neuronal-astrocytic cocultures. A superfusion paradigm was used to induce repetitively vesicular glutamate release by N-methyl-D-aspartate (NMDA) in the neurons, allowing the relative activity dependency of the lactate-alanine shuttle to be assessed. [(15)N]Alanine (0.2 mM), [2-(15)N]/[5-(15)N]glutamine...... (0.25 mM), and [(15)N]ammonia (0.3 mM) were used as precursors and cell extracts were analyzed by mass spectrometry. Labeling from [(15)N]alanine in glutamine, aspartate, and glutamate in cerebellar cocultures was independent of depolarization of the neurons. Employing glutamine with the amino group...

  3. Glutamate synthase: An archaeal horizontal gene transfer?

    Indian Academy of Sciences (India)

    (GOGAT) which is a key enzyme in ammonia assimilation in bacteria, algae and plants. It catalyzes the reductive transamidation of amido nitrogen from glutamine to 2-oxoglutarate to form two molecules of glutamate (Temple et al 1998). Glutamate synthases differ according to their molecular weights, subunit compositions, ...

  4. Activities of alkaline phosphatase, glutamate oxaloacetate ...

    African Journals Online (AJOL)

    Alkaline phosphatase, glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities were assessed in rats highly infected with federe strain of Trypanosoma brucei and treated with honey. Therapeutic effect of honey on parasitaemia was also assessed. Results show an extension in the life span of ...

  5. The blood-brain barrier and glutamate.

    Science.gov (United States)

    Hawkins, Richard A

    2009-09-01

    Glutamate concentrations in plasma are 50-100 micromol/L; in whole brain, they are 10,000-12,000 micromol/L but only 0.5-2 micromol/L in extracellular fluids (ECFs). The low ECF concentrations, which are essential for optimal brain function, are maintained by neurons, astrocytes, and the blood-brain barrier (BBB). Cerebral capillary endothelial cells form the BBB that surrounds the entire central nervous system. Tight junctions connect endothelial cells and separate the BBB into luminal and abluminal domains. Molecules entering or leaving the brain thus must pass 2 membranes, and each membrane has distinct properties. Facilitative carriers exist only in luminal membranes, and Na(+)-dependent glutamate cotransporters (excitatory amino acid transporters; EAATs) exist exclusively in abluminal membranes. The EAATs are secondary transporters that couple the Na(+) gradient between the ECF and the endothelial cell to move glutamate against the existing electrochemical gradient. Thus, the EAATs in the abluminal membrane shift glutamate from the ECF to the endothelial cell where glutamate is free to diffuse into blood on facilitative carriers. This organization does not allow net glutamate entry to the brain; rather, it promotes the removal of glutamate and the maintenance of low glutamate concentrations in the ECF. This explains studies that show that the BBB is impermeable to glutamate, even at high concentrations, except in a few small areas that have fenestrated capillaries (circumventricular organs). Recently, the question of whether the BBB becomes permeable in diabetes has arisen. This issue was tested in rats with diet-induced obesity and insulin resistance or with streptozotocin-induced diabetes. Neither condition produced any detectable effect on BBB glutamate transport.

  6. Lassa-vesicular stomatitis chimeric virus safely destroys brain tumors.

    Science.gov (United States)

    Wollmann, Guido; Drokhlyansky, Eugene; Davis, John N; Cepko, Connie; van den Pol, Anthony N

    2015-07-01

    High-grade tumors in the brain are among the deadliest of cancers. Here, we took a promising oncolytic virus, vesicular stomatitis virus (VSV), and tested the hypothesis that the neurotoxicity associated with the virus could be eliminated without blocking its oncolytic potential in the brain by replacing the neurotropic VSV glycoprotein with the glycoprotein from one of five different viruses, including Ebola virus, Marburg virus, lymphocytic choriomeningitis virus (LCMV), rabies virus, and Lassa virus. Based on in vitro infections of normal and tumor cells, we selected two viruses to test in vivo. Wild-type VSV was lethal when injected directly into the brain. In contrast, a novel chimeric virus (VSV-LASV-GPC) containing genes from both the Lassa virus glycoprotein precursor (GPC) and VSV showed no adverse actions within or outside the brain and targeted and completely destroyed brain cancer, including high-grade glioblastoma and melanoma, even in metastatic cancer models. When mice had two brain tumors, intratumoral VSV-LASV-GPC injection in one tumor (glioma or melanoma) led to complete tumor destruction; importantly, the virus moved contralaterally within the brain to selectively infect the second noninjected tumor. A chimeric virus combining VSV genes with the gene coding for the Ebola virus glycoprotein was safe in the brain and also selectively targeted brain tumors but was substantially less effective in destroying brain tumors and prolonging survival of tumor-bearing mice. A tropism for multiple cancer types combined with an exquisite tumor specificity opens a new door to widespread application of VSV-LASV-GPC as a safe and efficacious oncolytic chimeric virus within the brain. Many viruses have been tested for their ability to target and kill cancer cells. Vesicular stomatitis virus (VSV) has shown substantial promise, but a key problem is that if it enters the brain, it can generate adverse neurologic consequences, including death. We tested a series of

  7. Reduced Glutamate Release in Adult BTBR Mouse Model of Autism Spectrum Disorder.

    Science.gov (United States)

    Wei, Hongen; Ma, Yuehong; Ding, Caiyun; Jin, Guorong; Liu, Jianrong; Chang, Qiaoqiao; Hu, Fengyun; Yu, Li

    2016-11-01

    Autism spectrum disorder (ASD) is a developmental disorder characterized by impairments in social and communication abilities, as well as by restricted and repetitive behaviors. The BTBR T + Itpr3 tf (BTBR) mice have emerged as a well characterized and widely used mouse model of a range of ASD-like phenotype, showing deficiencies in social behaviors and unusual ultrasonic vocalizations as well as increased repetitive self-grooming. However, the inherited neurobiological changes that lead to ASD-like behaviors in these mice are incompletely known and still under active investigation. The aim of this study was to further evaluate the structure and neurotransmitter release of the glutamatergic synapse in BTBR mice. C57BL/6J (B6) mice were used as a control strain because of their high level of sociability. The important results showed that the evoked glutamate release in the cerebral cortex of BTBR mice was significantly lower than in B6 mice. And the level of vesicle docking-related protein Syntaxin-1A was reduced in BTBR mice. However, no significant changes were observed in the number of glutamatergic synapse, level of synaptic proteins, density of dendritic spine and postsynaptic density between BTBR mice and B6 mice. Overall, our results suggest that abnormal vesicular glutamate activity may underlie the ASD relevant pathology in the BTBR mice.

  8. Glutamate and Brain Glutaminases in Drug Addiction.

    Science.gov (United States)

    Márquez, Javier; Campos-Sandoval, José A; Peñalver, Ana; Matés, José M; Segura, Juan A; Blanco, Eduardo; Alonso, Francisco J; de Fonseca, Fernando Rodríguez

    2017-03-01

    Glutamate is the principal excitatory neurotransmitter in the central nervous system and its actions are related to the behavioral effects of psychostimulant drugs. In the last two decades, basic neuroscience research and preclinical studies with animal models are suggesting a critical role for glutamate transmission in drug reward, reinforcement, and relapse. Although most of the interest has been centered in post-synaptic glutamate receptors, the presynaptic synthesis of glutamate through brain glutaminases may also contribute to imbalances in glutamate homeostasis, a key feature of the glutamatergic hypothesis of addiction. Glutaminases are the main glutamate-producing enzymes in brain and dysregulation of their function have been associated with neurodegenerative diseases and neurological disorders; however, the possible implication of these enzymes in drug addiction remains largely unknown. This mini-review focuses on brain glutaminase isozymes and their alterations by in vivo exposure to drugs of abuse, which are discussed in the context of the glutamate homeostasis theory of addiction. Recent findings from mouse models have shown that drugs induce changes in the expression profiles of key glutamatergic transmission genes, although the molecular mechanisms that regulate drug-induced neuronal sensitization and behavioral plasticity are not clear.

  9. Expression of Vesicular Nucleotide Transporter in Rat Odontoblasts.

    Science.gov (United States)

    Ikeda, Erina; Goto, Tetsuya; Gunjigake, Kaori; Kuroishi, Kayoko; Ueda, Masae; Kataoka, Shinji; Toyono, Takashi; Nakatomi, Mitsushiro; Seta, Yuji; Kitamura, Chiaki; Nishihara, Tatsuji; Kawamoto, Tatsuo

    2016-02-27

    Several theories have been proposed regarding pain transmission mechanisms in tooth. However, the exact signaling mechanism from odontoblasts to pulp nerves remains to be clarified. Recently, ATP-associated pain transmission has been reported, but it is unclear whether ATP is involved in tooth pain transmission. In the present study, we focused on the vesicular nucleotide transporter (VNUT), a transporter of ATP into vesicles, and examined whether VNUT was involved in ATP release from odontoblasts. We examined the expression of VNUT in rat pulp by RT-PCR and immunostaining. ATP release from cultured odontoblast-like cells with heat stimulation was evaluated using ATP luciferase methods. VNUT was expressed in pulp tissue, and the distribution of VNUT-immunopositive vesicles was confirmed in odontoblasts. In odontoblasts, some VNUT-immunopositive vesicles were colocalized with membrane fusion proteins. Additionally P2X3, an ATP receptor, immunopositive axons were distributed between odontoblasts. The ATP release by thermal stimulation from odontoblast-like cells was inhibited by the addition of siRNA for VNUT. These findings suggest that cytosolic ATP is transported by VNUT and that the ATP in the vesicles is then released from odontoblasts to ATP receptors on axons. ATP vesicle transport in odontoblasts seems to be a key mechanism for signal transduction from odontoblasts to axons in the pulp.

  10. Understanding and altering cell tropism of vesicular stomatitis virus

    Science.gov (United States)

    Hastie, Eric; Cataldi, Marcela; Marriott, Ian; Grdzelishvili, Valery Z.

    2013-01-01

    Vesicular stomatitis virus (VSV) is a prototypic nonsegmented negative-strand RNA virus. VSV’s broad cell tropism makes it a popular model virus for many basic research applications. In addition, a lack of preexisting human immunity against VSV, inherent oncotropism and other features make VSV a widely used platform for vaccine and oncolytic vectors. However, VSV’s neurotropism that can result in viral encephalitis in experimental animals needs to be addressed for the use of the virus as a safe vector. Therefore, it is very important to understand the determinants of VSV tropism and develop strategies to alter it. VSV glycoprotein (G) and matrix (M) protein play major roles in its cell tropism. VSV G protein is responsible for VSV broad cell tropism and is often used for pseudotyping other viruses. VSV M affects cell tropism via evasion of antiviral responses, and M mutants can be used to limit cell tropism to cell types defective in interferon signaling. In addition, other VSV proteins and host proteins may function as determinants of VSV cell tropism. Various approaches have been successfully used to alter VSV tropism to benefit basic research and clinically relevant applications. PMID:23796410

  11. Asymmetric packaging of polymerases within vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Hodges, Jeffery; Tang, Xiaolin; Landesman, Michael B. [Dept. of Physics and Astronomy, University of Utah (United States); Center for Cell and Genome Science, University of Utah (United States); Ruedas, John B. [Dept. of Biology, San Diego State University (United States); Ghimire, Anil [Dept. of Physics and Astronomy, University of Utah (United States); Gudheti, Manasa V. [Vutara, Inc., Salt Lake City, UT (United States); Dept. of Biology, University of Utah (United States); Perrault, Jacques [Dept. of Biology, San Diego State University (United States); Jorgensen, Erik M. [Howard Hughes Medical Institute (United States); Dept. of Biology, University of Utah (United States); Gerton, Jordan M. [Dept. of Physics and Astronomy, University of Utah (United States); Dept. of Bioengineering, University of Utah (United States); Saffarian, Saveez, E-mail: saffarian@physics.utah.edu [Dept. of Physics and Astronomy, University of Utah (United States); Center for Cell and Genome Science, University of Utah (United States); Dept. of Biology, University of Utah (United States)

    2013-10-18

    Highlights: •The VSV polymerases (L proteins) are localized to the blunt end of the virus. •The VSV phosphoproteins (P proteins) are localized to the blunt end of the virus. •Each VSV virion packages a variable number of P and L proteins. -- Abstract: Vesicular stomatitis virus (VSV) is a prototypic negative sense single-stranded RNA virus. The bullet-shape appearance of the virion results from tightly wound helical turns of the nucleoprotein encapsidated RNA template (N-RNA) around a central cavity. Transcription and replication require polymerase complexes, which include a catalytic subunit L and a template-binding subunit P. L and P are inferred to be in the cavity, however lacking direct observation, their exact position has remained unclear. Using super-resolution fluorescence imaging and atomic force microscopy (AFM) on single VSV virions, we show that L and P are packaged asymmetrically towards the blunt end of the virus. The number of L and P proteins varies between individual virions and they occupy 57 ± 12 nm of the 150 nm central cavity of the virus. Our finding positions the polymerases at the opposite end of the genome with respect to the only transcriptional promoter.

  12. Understanding and altering cell tropism of vesicular stomatitis virus.

    Science.gov (United States)

    Hastie, Eric; Cataldi, Marcela; Marriott, Ian; Grdzelishvili, Valery Z

    2013-09-01

    Vesicular stomatitis virus (VSV) is a prototypic nonsegmented negative-strand RNA virus. VSV's broad cell tropism makes it a popular model virus for many basic research applications. In addition, a lack of preexisting human immunity against VSV, inherent oncotropism and other features make VSV a widely used platform for vaccine and oncolytic vectors. However, VSV's neurotropism that can result in viral encephalitis in experimental animals needs to be addressed for the use of the virus as a safe vector. Therefore, it is very important to understand the determinants of VSV tropism and develop strategies to alter it. VSV glycoprotein (G) and matrix (M) protein play major roles in its cell tropism. VSV G protein is responsible for VSV broad cell tropism and is often used for pseudotyping other viruses. VSV M affects cell tropism via evasion of antiviral responses, and M mutants can be used to limit cell tropism to cell types defective in interferon signaling. In addition, other VSV proteins and host proteins may function as determinants of VSV cell tropism. Various approaches have been successfully used to alter VSV tropism to benefit basic research and clinically relevant applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation

    Directory of Open Access Journals (Sweden)

    Reshmy Rajan

    2011-01-01

    Full Text Available Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era.

  14. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation

    Science.gov (United States)

    Rajan, Reshmy; Jose, Shoma; Mukund, V. P. Biju; Vasudevan, Deepa T.

    2011-01-01

    Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era. PMID:22171309

  15. Molecular architecture of the vesicular stomatitis virus RNA polymerase.

    Science.gov (United States)

    Rahmeh, Amal A; Schenk, Andreas D; Danek, Eric I; Kranzusch, Philip J; Liang, Bo; Walz, Thomas; Whelan, Sean P J

    2010-11-16

    Nonsegmented negative-strand (NNS) RNA viruses initiate infection by delivering into the host cell a highly specialized RNA synthesis machine comprising the genomic RNA completely encapsidated by the viral nucleocapsid protein and associated with the viral polymerase. The catalytic core of this protein-RNA complex is a 250-kDa multifunctional large (L) polymerase protein that contains enzymatic activities for nucleotide polymerization as well as for each step of mRNA cap formation. Working with vesicular stomatitis virus (VSV), a prototype of NNS RNA viruses, we used negative stain electron microscopy (EM) to obtain a molecular view of L, alone and in complex with the viral phosphoprotein (P) cofactor. EM analysis, combined with proteolytic digestion and deletion mapping, revealed the organization of L into a ring domain containing the RNA polymerase and an appendage of three globular domains containing the cap-forming activities. The capping enzyme maps to a globular domain, which is juxtaposed to the ring, and the cap methyltransferase maps to a more distal and flexibly connected globule. Upon P binding, L undergoes a significant rearrangement that may reflect an optimal positioning of its functional domains for transcription. The structural map of L provides new insights into the interrelationship of its various domains, and their rearrangement on P binding that is likely important for RNA synthesis. Because the arrangement of conserved regions involved in catalysis is homologous, the structural insights obtained for VSV L likely extend to all NNS RNA viruses.

  16. [Safety of laparoscopic cholecystectomy in complicated vesicular disease].

    Science.gov (United States)

    Pérez-Morales, Alfonso; Roesch-Dietlen, Federico; Díaz-Blanco, Fernando; Martínez-Fernández, Silvia

    2005-01-01

    We assessed the experience and safety of cholecystectomy through laparoscopic approach in patients with complicated biliary gallbladder disease who were attended at the Hospital Español, Veracruz, Mexico, during a 10-year period. A prospective, longitudinal, comparative study with a control group was designed. We studied a group of patients with complicated cholelithiasis disease (Group I) and compared them with patients without complicated diseases. We analyzed the following variables: age, gender, risk factors, associated trans-operative pathology and accidents, surgical time, rate of conversion to open procedure, length of hospital stay, complications and evolution. During the 10-year period, 733 cholecystectomies were performed, 245 (33.42%) to treat complicated cholelithiasis and 488 (66.58%) uncomplicated. There were no differences regarding gender, age, risk factors, hospital stay, complications, morbidity and mortality, and iatrogenic lesions of the biliary tree, postoperative morbidity and mortality. In all patients of Group I (245), we found complications of cholelithiasis (acute cholecystitis, choledochal gallstones, vesicular adherences, and cholecystocolonic fistula). Surgical time was longer in Group I and surgical accidents made the surgical procedure more difficult. The overall results established that laparoscopic cholecystectomy in our institution is a safe procedure in patients with complicated gallbladder disease and can be performed by experienced surgeons.

  17. Cocaine-induced neuroadaptations in glutamate transmission

    Science.gov (United States)

    Schmidt, Heath D.; Pierce, R. Christopher

    2017-01-01

    A growing body of evidence indicates that repeated exposure to cocaine leads to profound changes in glutamate transmission in limbic nuclei, particularly the nucleus accumbens. This review focuses on preclinical studies of cocaine-induced behavioral plasticity, including behavioral sensitization, self-administration, and the reinstatement of cocaine seeking. Behavioral, pharmacological, neurochemical, electrophysiological, biochemical, and molecular biological changes associated with cocaine-induced plasticity in glutamate systems are reviewed. The ultimate goal of these lines of research is to identify novel targets for the development of therapies for cocaine craving and addiction. Therefore, we also outline the progress and prospects of glutamate modulators for the treatment of cocaine addiction. PMID:20201846

  18. Metabolic fate and function of dietary glutamate in the gut

    Science.gov (United States)

    Glutamate is a major constituent of dietary protein and is also consumed in many prepared foods as an additive in the form of monosodium glutamate. Evidence from human and animal studies indicates that glutamate is a major oxidative fuel for the gut and that dietary glutamate is extensively metabol...

  19. Emerging aspects of dietary glutamate metabolism in the developing gut

    Science.gov (United States)

    Glutamate is a major constituent of dietary protein and is also consumed in many prepared foods as a flavour additive in the form of monosodium glutamate (MSG). Evidence from human and animal studies indicates that glutamate is the major oxidative fuel for the gut and that dietary glutamate is exten...

  20. Modulation of glutamate transport and receptor binding by glutamate receptor antagonists in EAE rat brain.

    Directory of Open Access Journals (Sweden)

    Grzegorz Sulkowski

    Full Text Available The etiology of multiple sclerosis (MS is currently unknown. However, one potential mechanism involved in the disease may be excitotoxicity. The elevation of glutamate in cerebrospinal fluid, as well as changes in the expression of glutamate receptors (iGluRs and mGluRs and excitatory amino acid transporters (EAATs, have been observed in the brains of MS patients and animals subjected to experimental autoimmune encephalomyelitis (EAE, which is the predominant animal model used to investigate the pathophysiology of MS. In the present paper, the effects of glutamatergic receptor antagonists, including amantadine, memantine, LY 367583, and MPEP, on glutamate transport, the expression of mRNA of glutamate transporters (EAATs, the kinetic parameters of ligand binding to N-methyl-D-aspartate (NMDA receptors, and the morphology of nerve endings in EAE rat brains were investigated. The extracellular level of glutamate in the brain is primarily regulated by astrocytic glutamate transporter 1 (GLT-1 and glutamate-aspartate transporter (GLAST. Excess glutamate is taken up from the synaptic space and metabolized by astrocytes. Thus, the extracellular level of glutamate decreases, which protects neurons from excitotoxicity. Our investigations showed changes in the expression of EAAT mRNA, glutamate transport (uptake and release by synaptosomal and glial plasmalemmal vesicle fractions, and ligand binding to NMDA receptors; these effects were partially reversed after the treatment of EAE rats with the NMDA antagonists amantadine and memantine. The antagonists of group I metabotropic glutamate receptors (mGluRs, including LY 367385 and MPEP, did not exert any effect on the examined parameters. These results suggest that disturbances in these mechanisms may play a role in the processes associated with glutamate excitotoxicity and the progressive brain damage in EAE.

  1. Mechanism for the activation of glutamate receptors

    Science.gov (United States)

    Scientists at the NIH have used a technique called cryo-electron microscopy to determine a molecular mechanism for the activation and desensitization of ionotropic glutamate receptors, a prominent class of neurotransmitter receptors in the brain and spina

  2. Biobased synthesis of acrylonitrile from glutamic acid

    NARCIS (Netherlands)

    Notre, le J.E.L.; Scott, E.L.; Franssen, M.C.R.; Sanders, J.P.M.

    2011-01-01

    Glutamic acid was transformed into acrylonitrile in a two step procedure involving an oxidative decarboxylation in water to 3-cyanopropanoic acid followed by a decarbonylation-elimination reaction using a palladium catalyst

  3. Monosodium glutamate: Potentials at inducing prostate pathologies ...

    African Journals Online (AJOL)

    ONOS

    2010-09-06

    Sep 6, 2010 ... either MSG or DW. Key words: Monosodium glutamate, total acid phosphatase, prostatic acid phosphatase, prostate cancer, prostatitis, benign prostate hyperplasia, infertility. INTRODUCTION. Elevated total acid phosphatase (TAP) and prostatic acid phosphatase (PAP) activities are among the main.

  4. Redistributive properties of the vesicular stomatitis virus polymerase

    Energy Technology Data Exchange (ETDEWEB)

    Helfman, W.B.; Perrault, J. (San Diego State Univ., CA (USA))

    1989-08-01

    The template for transcription of the vesicular stomatitis virus (VSV) genome consists of a negative-strand RNA (approximately 11 kb) tightly associated with approximately 1250 copies of the nucleocapsid or N protein (N-RNA template). The interaction between the virion-associated polymerase and this template was probed with a novel assay using purified N-RNA complexes added to detergent-disrupted uv-irradiated standard virions or unirradiated defective interfering (DI) particles. In contrast to the well-known stability of assembled cellular transcription complexes, the VSV polymerase copied exogenously added templates efficiently and yielded products indistinguishable from control virus transcription. Addition of uv-irradiated N-RNA templates to unirradiated virus effectively competed for transcription of endogenous template indicating that most or all of the polymerase can freely redistribute. Furthermore preincubation of virus and added templates at high ionic strength to solubilize L and NS polymerase proteins did not release additional active enzyme for redistribution. Pretranscription of virus also had little or no effect on redistributed activity indicating that polymerase complexes are capable of multiple rounds of synthesis beginning at the 3' end promoter. Unexpectedly, titration with saturating amounts of added N-RNA showed that active polymerase complexes are only in slight excess relative to template in standard or DI particles despite the large surplus of packaged L and NS polypeptides. Moreover, added standard virus templates competed equally well for the redistributing polymerase from DI particles or standard virus indicating no significant polymerase-binding preference for interfering templates. These findings bear important implications regarding mechanisms of VSV transcription and replication.

  5. Inhibition of cellular DNA synthesis by vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, J.J.; Wagner, R.R.

    1981-04-01

    DNA synthesis in mouse myeloma (MPC-11) cells and L cells was rapidly and progressively inhibited by infection with vesicular stomatitis virus (VSV). No significant difference in cellular DNA synthesis inhibition was noted between synchronized and unsynchronized cells, nor did synchronized cells vary in their susceptibility to VSV infection after release from successive thymidine and hydroxyurea blocks. Cellular RNA synthesis was inhibited to about the same extent as DNA synthesis, but cellular protein synthesis was less affected by VSV at the same multiplicity of infection. The effect of VSV on cellular DNA synthesis could not be attributed to degradation of existing DNA or to decreased uptake of deoxynucleoside triphosphates, nor were DNA polymerase and thymidine kinase activities significantly different in VSV-infected and uninfected cell extracts. Analysis by alkaline sucrose gradients of DNA in pulse-labeled uninfected and VSV-infected cells indicated that VSV infection did not appear to influence DNA chain elongation. Cellular DNA synthesis was not significantly inhibited by infection with the VSV polymerase mutant tsG114(I) at the restrictive temperature or by infection with defective-interfering VSV DI-011 (5' end of the genome), but DI-HR-LT (3' end of genome) exhibited initially rapid but not prolonged inhibition of MPC-11 cell DNA synthesis. DNA synthesis inhibitory activity of wild-type VSV was only slowly and partially inactivated by very large doses of UV irradiation. These data suggest that, as in the effect of VSV on cellular RNA synthesis inhibition of cellular DNA synthesis by VSV requires transcription of a small segment of the viral genome.

  6. Intracellular synthesis of glutamic acid in Bacillus methylotrophicus SK19.001, a glutamate-independent poly(γ-glutamic acid)-producing strain.

    Science.gov (United States)

    Peng, Yingyun; Zhang, Tao; Mu, Wanmeng; Miao, Ming; Jiang, Bo

    2016-01-15

    Bacillus methylotrophicus SK19.001 is a glutamate-independent strain that produces poly(γ-glutamic acid) (γ-PGA), a polymer of D- and L-glutamic acids that possesses applications in food, the environment, agriculture, etc. This study was undertaken to explore the synthetic pathway of intracellular L- and D-glutamic acid in SK19.001 by investigating the effects of tricarboxylic acid cycle intermediates and different amino acids as metabolic precursors on the production of γ-PGA and analyzing the activities of the enzymes involved in the synthesis of L- and D-glutamate. Tricarboxylic acid cycle intermediates and amino acids could participate in the synthesis of γ-PGA via independent pathways in SK19.001. L-Aspartate aminotransferase, L-glutaminase and L-glutamate synthase were the enzymatic sources of L-glutamate. Glutamate racemase was responsible for the formation of D-glutamate for the synthesis of γ-PGA, and the synthetase had stereoselectivity for glutamate substrate. The enzymatic sources of L-glutamate were investigated for the first time in the glutamate-independent γ-PGA-producing strain, and multiple enzymatic sources of L-glutamate were verified in SK19.001, which will benefit efforts to improve production of γ-PGA with metabolic engineering strategies. © 2015 Society of Chemical Industry.

  7. Vesicular Contact Reaction May Progress into Erythema Multiforme.

    Science.gov (United States)

    Czarnecka-Operacz, Magdalena; Jenerowicz, Dorota; Szulczyńska-Gabor, Joanna; Teresiak-Mikołajczak, Ewa; Szyfter-Harris, Joanna; Bowszyc-Dmochowska, Monika

    2016-12-01

    Dear Editor, Erythema multiforme is considered an acute skin condition, characterized by a self-limiting and sometimes recurrent course. It is regarded as a type IV hypersensitivity reaction associated with certain infections, medications, and other various triggers. Allergic contact dermatitis is in turn a delayed type of induced allergy as a result of cutaneous contact with a specific allergen to which the patient develops specific sensitivity. This type of cutaneous reaction is associated with inflammation manifesting with erythema, edema, and vesicles. A 27-year old female patient presented with a 3-day history of erythematous and vesicular lesions which developed 24 hours after cesarean section. Initially the lesions were localized in the area of surgery (mainly the abdomen and upper thighs) and on the next day progressed to the buttocks and lumbar area. The patient was referred to the Outpatient Clinic and was treated with antihistamines, but her dermatological state deteriorated rapidly. At the day of admission to the Department of Dermatology, numerous erythematous and vesicular lesions were present on the skin of the abdomen, thighs, and back (Figure 1, a), but the skin of the neck, chest, and extremities was also covered with erythematous and edematous patches. On the second day of hospitalization, we observed the evolution of lesions localized within the chest and extremities into an erythema multiforme-like targetoid eruption (Figure 1, b). Initially the patient was treated with intravenous injections of dexamethasone and ceftriaxone and orally with second-generation antihistamines (in four-fold doses), followed by intravenous metyloprednisolone pulse-therapy (total dose of 3 g). As the new vesicobullous lesions started to appear on the face and arms, we introduced cyclosporine A orally 400 mg daily. We could then observe gradual remission, but on the seventh day of hospitalization the patient developed a massive labial herpes simplex infection and had

  8. The application of glutamic acid alpha-decarboxylase for the valorization of glutamic acid

    NARCIS (Netherlands)

    Lammens, T.M.; Biase, De Daniela; Franssen, M.C.R.; Scott, E.L.; Sanders, J.P.M.

    2009-01-01

    Glutamic acid is an important constituent of waste streams from biofuels production. It is an interesting starting material for the synthesis of nitrogen containing bulk chemicals, thereby decreasing the dependency on fossil fuels. On the pathway from glutamic acid to a range of molecules, the

  9. The Degradation of 14C-Glutamic Acid by L-Glutamic Acid Decarboxylase.

    Science.gov (United States)

    Dougherty, Charles M; Dayan, Jean

    1982-01-01

    Describes procedures and semi-micro reaction apparatus (carbon dioxide trap) to demonstrate how a particular enzyme (L-Glutamic acid decarboxylase) may be used to determine the site or sites of labeling in its substrate (carbon-14 labeled glutamic acid). Includes calculations, solutions, and reagents used. (Author/SK)

  10. Mapping the distribution of vesicular textures on silicic lavas using the Thermal Infrared Multispectral Scanner

    Science.gov (United States)

    Ondrusek, Jaime; Christensen, Philip R.; Fink, Jonathan H.

    1993-01-01

    To investigate the effect of vesicularity on TIMS (Thermal Infrared Multispectral Scanner) imagery independent of chemical variations, we studied a large rhyolitic flow of uniform composition but textural heterogeneity. The imagery was recalibrated so that the digital number values for a lake in the scene matched a calculated ideal spectrum for water. TIMS spectra for the lava show useful differences in coarsely and finely vesicular pumice data, particularly in TIMS bands 3 and 4. Images generated by ratioing these bands accurately map out those areas known from field studies to be coarsely vesicular pumice. These texture-related emissivity variations are probably due to the larger vesicles being relatively deeper and separated by smaller septa leaving less smooth glass available to give the characteristic emission of the lava. In studies of inaccessible lava flows (as on Mars) areas of coarsely vesicular pumice must be identified and avoided before chemical variations can be interpreted. Remotely determined distributions of vesicular and glassy textures can also be related to the volatile contents and potential hazards associated with the emplacement of silicic lava flows on Earth.

  11. Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Rossana C.N., E-mail: rossana.melo@ufjf.edu.br [Laboratory of Cellular Biology, Department of Biology, ICB, Federal University of Juiz de Fora, UFJF, Rua José Lourenço Kelmer, Juiz de Fora, MG 36036-900 (Brazil); Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States); Weller, Peter F. [Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States)

    2016-10-01

    Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombrero Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.

  12. Vesicular exanthema of swine virus: isolation and serotyping of field samples.

    Science.gov (United States)

    Edwards, J F; Yedloutschnig, R J; Dardiri, A H; Callis, J J

    1987-01-01

    Virus isolation was attempted from 262 field samples of vesicular material collected during the outbreaks of vesicular exanthema of swine in the U.S.A. from 1952-54. Using primary swine kidney culture, viral cytopathogenic agents were isolated from 76.3% of the samples. However, an overall recovery rate of 82.1% was obtained after samples negative in tissue culture were inoculated intradermally in susceptible swine. All vesicular exanthema of swine virus isolates were identified as serotype B51 using complement fixation and serum neutralization tests. Two isolates did not react with antisera to known vesicular agents of swine and failed to produce vesicles or clinical signs of disease upon inoculation in swine. One vesicular exanthema of swine virus isolate from tissue of equine origin was pathogenic for swine but produced limited vesiculation at the site of intradermalingual inoculation in the tongue of a pony infected experimentally. Type B51 virus was reisolated from lesions produced in the pony and the pony became seropositive for virus type B51. PMID:3651889

  13. Quantitative Chemical Measurements of Vesicular Transmitters with Electrochemical Cytometry.

    Science.gov (United States)

    Li, Xianchan; Dunevall, Johan; Ewing, Andrew G

    2016-10-18

    Electrochemical cytometry adds a new dimension to our ability to study the chemistry and chemical storage of transmitter molecules stored in nanometer vesicles. The approach involves the adsorption and subsequent rupture of vesicles on an electrode surface during which the electroactive contents are quantitatively oxidized (or reduced). The measured current allows us to count the number of molecules in the vesicles using Faraday's law and to correlate this to the amount of molecules released when single exocytosis events take place at communicating cells. The original format for this method involved a capillary electrophoresis separation step to singly address each vesicle, but we have more recently discovered that cellular vesicles tend to adsorb to carbon electrodes and spontaneously as well as stochastically rupture to give mostly single vesicle events. This approach, called impact electrochemical cytometry, even though the impact is perhaps not the important part of this process, has been studied and the vesicle rupture appears to be at the interface between the vesicle and the electrode and is probably driven by electroporation. The pore size and rate of content electrolysis are a function of the pore diameter and the presence of a protein core in the vesicles. In model liposomes with no protein, events appear extremely rapidly as the soft nanoparticles impact the electrode and the contents are oxidized. It appears that the proteins decorating the surface of the vesicle are important in maintaining a gap from the electrode and when this gap is closed electroporation takes place. Models of the event response times suggest the pores formed are small enough so we can carry out these measurements at nanotip electrodes and we have used this to quantify the vesicle content in living cells in a mode we call intracellular impact electrochemical cytometry. The development of electrochemical cytometry allows comparison between vesicle content and vesicular release and

  14. Glutamic acid modification of vincristine toxicity.

    Science.gov (United States)

    Jackson, D V; Rosenbaum, D L; Carlisle, L J; Long, T R; Wells, H B; Spurr, C L

    1984-09-01

    The principal limiting feature of the antitumor agent, vincristine, in the clinic has been neurotoxicity; there are no known agents which can routinely prevent or decrease this side effect. Glutamic acid in laboratory and clinical investigations in the early 1960s was found to antagonize vinblastine, another clinically useful vinca alkaloid. Glutamic acid 250 mg/kg/d i.p. was given to normal mice treated with repetitive doses of vincristine 1.5 mg/kg every other day. When glutamic acid was given both before and during vincristine administration, it produced a 49-79% increase in survival compared to control mice receiving vincristine only (p less than 0.01). Other schedules of glutamic acid administration were ineffective. Also, there appeared to be a delay in development of neurotoxic manifestations (toe-walking gait) but the results were not as consistent as the improvement in survival. Glutamic acid given to tumor-bearing mice (P-388 and P-1534 murine leukemia) did not inhibit the antitumor effect of vincristine-induced host toxicity in a schedule-dependent fashion without inhibition of the antitumor effect of vincristine.

  15. Historia natural del virus de la estomatitis vesicular en zonas enzoóticas de Antioquia

    OpenAIRE

    John Arboleda; Andrés Londoño; Víctor Quiroz; Carlos Trujillo

    2003-01-01

    La Estomatitis Vesicular (EV) es una enfermedad producida
    por el virus de la Estomatitis Vesicular, serotipos New Jersey (VSV-NJ) e Indiana (VSV-IN), afecta bovinos y equinos, porcinos y causa infección natural en humanos, principalmente granjeros, ordeñadores y personal de laboratorio.
    Se caracteriza por producir vesículas en las membranas mucosas
    de la boca (epitelio de la lengua y el paladar), bandas coronarias,
    pezones y tejidos blandos...

  16. Metabotropic Glutamate Receptor 5 and Glutamate Involvement in Major Depressive Disorder: A Multimodal Imaging Study.

    Science.gov (United States)

    Abdallah, Chadi G; Hannestad, Jonas; Mason, Graeme F; Holmes, Sophie E; DellaGioia, Nicole; Sanacora, Gerard; Jiang, Lihong; Matuskey, David; Satodiya, Ritvij; Gasparini, Fabrizio; Lin, Xin; Javitch, Jonathan; Planeta, Beata; Nabulsi, Nabeel; Carson, Richard E; Esterlis, Irina

    2017-07-01

    Preclinical and postmortem studies have implicated the metabotropic glutamate receptor 5 (mGluR5) in the pathophysiology of major depressive disorder (MDD). The goal of the present study was to determine the role of mGluR5 in a large group of individuals with MDD compared to healthy controls (HC) in vivo with [(18)F]FPEB and positron emission tomography (PET). Furthermore, we sought to determine the role glutamate plays on mGluR5 availability in MDD. Sixty-five participants (30 MDD and 35 HC) completed [(18)F]FPEB PET to estimate the primary outcome measure - mGluR5 volume of distribution (VT), and the secondary outcome measure - mGluR5 distribution volume ratio (DVR). A subgroup of 39 participants (16 MDD and 23 HC) completed proton magnetic resonance spectroscopy ((1)H MRS) to estimate anterior cingulate (ACC) glutamate, glutamine, and Glx (glutamate + glutamine) levels relative to creatine (Cr). No significant between-group differences were observed in mGluR5 VT or DVR. Compared to HC, individuals with MDD had higher ACC glutamate, glutamine, and Glx levels. Importantly, the ACC mGluR5 DVR negatively correlated with glutamate/Cr and Glx/Cr levels. In this novel in vivo examination, we show an inverse relationship between mGluR5 availability and glutamate levels. These data highlight the need to further investigate the role of glutamatergic system in depression.

  17. Cytopathogenesis of Vesicular Stomatitis virus is regulated by the PSAP motif of M protein in a species-dependent manner

    Science.gov (United States)

    Vesicular stomatitis virus (VSV) is an important vector-borne pathogen of bovine and equine species, causing a reportable vesicular disease. The matrix (M) protein of VSV is multifunctional and plays a key role in cytopathogenesis, apoptosis, host protein shut-off, and virion assembly/budding. Our ...

  18. A putative vesicular transporter expressed in Drosophila mushroom bodies that mediates sexual behavior may define a novel neurotransmitter system

    Science.gov (United States)

    Brooks, Elizabeth S.; Greer, Christina L.; Romero-Calderón, Rafael; Serway, Christine N.; Grygoruk, Anna; Haimovitz, Jasmine M.; Nguyen, Bac T.; Najibi, Rod; Tabone, Christopher J.; de Belle, J. Steven; Krantz, David E.

    2011-01-01

    Summary Storage and release of classical and amino acid neurotransmitters requires vesicular transporters. Some neurons lack known vesicular transporters, suggesting additional neurotransmitter systems remain unidentified. Insect mushroom bodies (MBs) are critical for several behaviors, including learning, but the neurotransmitters released by the intrinsic Kenyon cells (KCs) remain unknown. Likewise, KCs do not express a known vesicular transporter. We report the identification of a novel Drosophila gene portabella (prt) that is structurally similar to known vesicular transporters. Both larval and adult brains express PRT in the KCs of the MBs. Additional PRT cells project to the central complex and optic ganglia. prt mutation causes an olfactory learning deficit and an unusual defect in the male’s position during copulation that is rescued by expression in KCs. Since prt is expressed in neurons that lack other known vesicular transporters or neurotransmitters, it may define a previously unknown neurotransmitter system responsible for sexual behavior and a component of olfactory learning. PMID:22017990

  19. The beneficial effect of dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover

    Directory of Open Access Journals (Sweden)

    Lin, XG.

    1993-01-01

    Full Text Available Investigation on the effect of phosphorus on vesicular-arbuscular mycorrhizal infection, and dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover under field microplots and pot experiments was conducted on fluvo-aquic soils of semi-arid region in north China. The results showed that 60 kg P205 ha in form of superphosphate was the most favorable phosphorus level for vesicular-arbuscular mycorrhizal infection ; mycorrhizal infection, nodulation, dry weight of shoots and roots, total uptake of nitrogen, phosphorus and other elements, the final yields and recovery of phosphorus of white clover were significantly increased by vesicular-arbuscular mycorrhizal inoculation and dual inoculation with vesicular-arbuscular mycorrhizal fungi and rhizobium. The highest response of inoculation was obtained by adding fertilizer phosphorus at the level of 60 kg P205 ha in form of superphosphate.

  20. 78 FR 76321 - Monosodium Glutamate From China and Indonesia

    Science.gov (United States)

    2013-12-17

    ... COMMISSION Monosodium Glutamate From China and Indonesia Determinations On the basis of the record \\1... injured by reason of imports from China and Indonesia of monosodium glutamate, provided for in subheading... imports of monosodium glutamate from China and Indonesia that are subsidized by the Governments of China...

  1. 21 CFR 182.1047 - Glutamic acid hydrochloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Glutamic acid hydrochloride. 182.1047 Section 182.1047 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1047 Glutamic acid hydrochloride. (a) Product. Glutamic acid hydrochloride. (b...

  2. Influence of Glutamic Acid on the Properties of Poly(xylitol glutamate sebacate Bioelastomer

    Directory of Open Access Journals (Sweden)

    Weifu Dong

    2013-11-01

    Full Text Available In order to further improve the biocompatibility of xylitol based poly(xylitol sebacate (PXS bioelastomer, a novel kind of amino acid based poly(xylitol glutamate sebacate (PXGS has been successfully prepared in this work by melt polycondensation of xylitol, N-Boc glutamic acid and sebacic acid. Differential scanning calorimetry (DSC results indicated the glass-transition temperatures could be decreased by feeding N-Boc glutamic acid. In comparison to PXS, PXGS exhibited comparable tensile strength and much higher elongation at break at the same ratio of acid/xylitol. The introduction of glutamic acid increased the hydrophilicity and in vitro degradation rate of the bioelastomer. It was found that PXGS exhibited excellent properties, such as tensile properties, biodegradability and hydrophilicity, which could be easily tuned by altering the feeding monomer ratios. The amino groups in the PXGS polyester side chains are readily functionalized, thus the biomelastomers can be considered as potential biomaterials for biomedical application.

  3. Glutamate Mediated Astrocytic Filtering of Neuronal Activity

    Science.gov (United States)

    Herzog, Nitzan; De Pittà, Maurizio; Jacob, Eshel Ben; Berry, Hugues; Hanein, Yael

    2014-01-01

    Neuron-astrocyte communication is an important regulatory mechanism in various brain functions but its complexity and role are yet to be fully understood. In particular, the temporal pattern of astrocyte response to neuronal firing has not been fully characterized. Here, we used neuron-astrocyte cultures on multi-electrode arrays coupled to Ca2+ imaging and explored the range of neuronal stimulation frequencies while keeping constant the amount of stimulation. Our results reveal that astrocytes specifically respond to the frequency of neuronal stimulation by intracellular Ca2+ transients, with a clear onset of astrocytic activation at neuron firing rates around 3-5 Hz. The cell-to-cell heterogeneity of the astrocyte Ca2+ response was however large and increasing with stimulation frequency. Astrocytic activation by neurons was abolished with antagonists of type I metabotropic glutamate receptor, validating the glutamate-dependence of this neuron-to-astrocyte pathway. Using a realistic biophysical model of glutamate-based intracellular calcium signaling in astrocytes, we suggest that the stepwise response is due to the supralinear dynamics of intracellular IP3 and that the heterogeneity of the responses may be due to the heterogeneity of the astrocyte-to-astrocyte couplings via gap junction channels. Therefore our results present astrocyte intracellular Ca2+ activity as a nonlinear integrator of glutamate-dependent neuronal activity. PMID:25521344

  4. Monosodium glutamate: Potentials at inducing prostate pathologies ...

    African Journals Online (AJOL)

    The health implication of the alteration could be compounded by the opposing response elicited by increasing the concentration of either MSG or DW. Key words: Monosodium glutamate, total acid phosphatase, prostatic acid phosphatase, prostate cancer, prostatitis, benign prostate hyperplasia, infertility. African Journal of ...

  5. Increase in vesicular hand eczema after house dust mite inhalation provocation : a double-blind, placebo-controlled, cross-over study

    NARCIS (Netherlands)

    Schuttelaar, Marielouise; Coenraads, Pieter Jan; Huizinga, Janneke; De Monchy, Jan G; Vermeulen, Karin M

    BACKGROUND: It is unclear whether the respiratory tract is involved in eliciting or aggravating eczematous lesions in patients with vesicular hand eczema. Objectives. To investigate the effect of inhalation of house dust mite (HDM) on vesicular hand eczema. METHODS: Eighteen patients with vesicular

  6. Detection of three porcine vesicular viruses using multiplex real-time primer-probe energy transfer

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Uttenthal, Åse; Aguero, M.

    2006-01-01

    Rapid identification of the etiologic agent in infected animals is important for the control of an outbreak of vesicular disease in livestock. We have in the present study developed a multiplex real-time reverse transcription-PCR, based on primer-probe energy transfer (PriProET), for simultaneous...

  7. Vesicular stomatitis virus-based vaccines against Lassa and Ebola viruses.

    Science.gov (United States)

    Marzi, Andrea; Feldmann, Friederike; Geisbert, Thomas W; Feldmann, Heinz; Safronetz, David

    2015-02-01

    We demonstrated that previous vaccination with a vesicular stomatitis virus (VSV)-based Lassa virus vaccine does not alter protective efficacy of subsequent vaccination with a VSV-based Ebola virus vaccine. These findings demonstrate the utility of VSV-based vaccines against divergent viral pathogens, even when preexisting immunity to the vaccine vector is present.

  8. TNF-mediated survival of CD169(+) cells promotes immune activation during vesicular stomatitis virus infection

    DEFF Research Database (Denmark)

    Shinde, Prashant V; Xu, Haifeng C; Maney, Sathish Kumar

    2017-01-01

    Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169(+) cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169(+) cells during viral infections remain ...

  9. Toluene-induced, Ca2+-dependent vesicular catecholamine release in rat PC12 cells

    NARCIS (Netherlands)

    Westerink, R.H.S.|info:eu-repo/dai/nl/239425952; Vijverberg, H.P.M.|info:eu-repo/dai/nl/068856474

    2002-01-01

    Acute effects of toluene on vesicular catecholamine release from intact PC12 phaeochromocytoma cells have been investigated using carbon fiber microelectrode amperometry. The frequency of vesicles released is low under basal conditions and is enhanced by depolarization. Toluene causes an increase in

  10. Influence of the preparation route on the supramolecular organization of lipids in a vesicular system

    DEFF Research Database (Denmark)

    Elizondo, Elisa; Larsen, Jannik; Hatzakis, Nikos

    2012-01-01

    A confocal fluorescence microscopy-based assay was used for studying the influence of the preparation route on the supramolecular organization of lipids in a vesicular system. In this work, vesicles composed of cholesterol and CTAB (1/1 mol %) or cholesterol and DOPC (2/8 mol %) and incorporating...

  11. [Seminal vesicular cysts associated with renal agenesis, ipsilateral ureter and hemitrigone. Report of a case].

    Science.gov (United States)

    Llopis Mínguez, B; Ferrutxe Frau, J; Moreno Pardo, B; Baixauli Martínez, J M; Moreno Barrachina, E; Rodríguez Hernández, J H

    1979-01-01

    A case is presented of seminal vesicular cyst associated with kidney agenesia, ipsilateral ureter and hemitrigon; this is the 17th case presented in the world literature reviewed. A study is made of all the cases published and the authors recommend deferento-vesiculography as the best means of diagnosis and total excision of the cyst as the most effective treatment.

  12. 9 CFR 94.12 - Pork and pork products from regions where swine vesicular disease exists.

    Science.gov (United States)

    2010-01-01

    ... exists. (a) Swine vesicular disease is considered to exist in all regions of the world except Australia..., Latvia, Lithuania, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Panama, Poland, Portugal..., the pork or pork products must be moved under Department seals or seals of the U.S. Customs Service...

  13. The development and significance of vesicular-arbuscular mycorrhizas as influenced by agricultural practices

    NARCIS (Netherlands)

    Ruissen, M.A.

    1982-01-01

    The development and significance of vesicular- arbuscular mycorrhizas (VAM) in wheat and potatoes have been studied in relation to various farming systems and agricultural practices. The effects of farming systems on VAM have been observed on three neighbouring experimental farms in the vicinity of

  14. Nanoscale distribution of presynaptic Ca(2+) channels and its impact on vesicular release during development.

    Science.gov (United States)

    Nakamura, Yukihiro; Harada, Harumi; Kamasawa, Naomi; Matsui, Ko; Rothman, Jason S; Shigemoto, Ryuichi; Silver, R Angus; DiGregorio, David A; Takahashi, Tomoyuki

    2015-01-07

    Synaptic efficacy and precision are influenced by the coupling of voltage-gated Ca(2+) channels (VGCCs) to vesicles. But because the topography of VGCCs and their proximity to vesicles is unknown, a quantitative understanding of the determinants of vesicular release at nanometer scale is lacking. To investigate this, we combined freeze-fracture replica immunogold labeling of Cav2.1 channels, local [Ca(2+)] imaging, and patch pipette perfusion of EGTA at the calyx of Held. Between postnatal day 7 and 21, VGCCs formed variable sized clusters and vesicular release became less sensitive to EGTA, whereas fixed Ca(2+) buffer properties remained constant. Experimentally constrained reaction-diffusion simulations suggest that Ca(2+) sensors for vesicular release are located at the perimeter of VGCC clusters (<30 nm) and predict that VGCC number per cluster determines vesicular release probability without altering release time course. This "perimeter release model" provides a unifying framework accounting for developmental changes in both synaptic efficacy and time course. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Deletion of glutamate dehydrogenase 1 (Glud1) in the central nervous system affects glutamate handling without altering synaptic transmission

    DEFF Research Database (Denmark)

    Frigerio, Francesca; Karaca, Melis; De Roo, Mathias

    2012-01-01

    Glutamate dehydrogenase (GDH), encoded by GLUD1, participates in the breakdown and synthesis of glutamate, the main excitatory neurotransmitter. In the CNS, besides its primary signaling function, glutamate is also at the crossroad of metabolic and neurotransmitter pathways. Importance of brain G...... transporters and of glutamine synthetase. Present data show that the lack of GDH in the CNS modifies the metabolic handling of glutamate without altering synaptic transmission....

  16. Amperometric L-glutamate biosensor based on bacterial cell-surface displayed glutamate dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Bo [Laboratory for Biosensing, Key Laboratory of Biofuels, and Shandong Provinicial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101 (China); University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 (China); Zhang, Shu [Laboratory for Biosensing, Key Laboratory of Biofuels, and Shandong Provinicial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101 (China); Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education, Ocean University of China, 238 Songling Road, Qingdao 266100 (China); Lang, Qiaolin [Laboratory for Biosensing, Key Laboratory of Biofuels, and Shandong Provinicial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101 (China); Song, Jianxia; Han, Lihui [Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education, Ocean University of China, 238 Songling Road, Qingdao 266100 (China); Liu, Aihua, E-mail: liuah@qibebt.ac.cn [Laboratory for Biosensing, Key Laboratory of Biofuels, and Shandong Provinicial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101 (China); University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049 (China)

    2015-07-16

    Highlights: • E. coli surface-dispalyed Gldh exhibiting excellent enzyme activity and stability. • Sensitive amperometric biosensor for glutamate using Gldh-bacteria and MWNTs. • The glutamate biosensor exhibited high specificity and stability. - Abstract: A novel L-glutamate biosensor was fabricated using bacteria surface-displayed glutamate dehydrogenase (Gldh-bacteria). Here the cofactor NADP{sup +}-specific dependent Gldh was expressed on the surface of Escherichia coli using N-terminal region of ice nucleation protein (INP) as the anchoring motif. The cell fractionation assay and SDS-PAGE analysis indicated that the majority of INP-Gldh fusion proteins were located on the surface of cells. The biosensor was fabricated by successively casting polyethyleneimine (PEI)-dispersed multi-walled carbon nanotubes (MWNTs), Gldh-bacteria and Nafion onto the glassy carbon electrode (Nafion/Gldh-bacteria/PEI-MWNTs/GCE). The MWNTs could not only significantly lower the oxidation overpotential towards NAPDH, which was the product of NADP{sup +} involving in the oxidation of glutamate by Gldh, but also enhanced the current response. Under the optimized experimental conditions, the current–time curve of the Nafion/Gldh-bacteria/PEI-MWNTs/GCE was performed at +0.52 V (vs. SCE) by amperometry varying glutamate concentration. The current response was linear with glutamate concentration in two ranges (10 μM–1 mM and 2–10 mM). The low limit of detection was estimated to be 2 μM glutamate (S/N = 3). Moreover, the proposed biosensor is stable, specific, reproducible and simple, which can be applied to real samples detection.

  17. Systemic administration of monosodium glutamate elevates intramuscular glutamate levels and sensitizes rat masseter muscle afferent fibers.

    Science.gov (United States)

    Cairns, Brian E; Dong, Xudong; Mann, Mandeep K; Svensson, Peter; Sessle, Barry J; Arendt-Nielsen, Lars; McErlane, Keith M

    2007-11-01

    There is evidence that elevated tissue concentrations of glutamate may contribute to pain and sensitivity in certain musculoskeletal pain conditions. In the present study, the food additive monosodium glutamate (MSG) was injected intravenously into rats to determine whether it could significantly elevate interstitial concentrations of glutamate in the masseter muscle and whether MSG administration could excite and/or sensitize slowly conducting masseter afferent fibers through N-methyl-D-aspartate (NMDA) receptor activation. The interstitial concentration of glutamate after systemic injection of isotonic phosphate-buffered saline (control) or MSG (10 and 50mg/kg) was measured with a glutamate-selective biosensor. The pre-injection baseline interstitial concentration of glutamate in the rat masseter muscle was 24+/-11 microM. Peak interstitial concentration after injection of 50mg/kg MSG was 63+/-18 microM and remained elevated above baseline for approximately 18 min. In vivo single unit recording experiments were undertaken to assess the effect of MSG (50mg/kg) on masseter afferent fibers. Injection of MSG evoked a brief discharge in one afferent fiber, and significantly decreased ( approximately 25%) the average afferent mechanical threshold (n=10) during the first 5 min after injection of MSG. Intravenous injection of ketamine (1mg/kg), 5 min prior to MSG, prevented the MSG-induced decreases in the mechanical threshold of masseter afferent fibers. The present results indicate that a 2- to 3-fold elevation in interstitial glutamate levels in the masseter muscle is sufficient to excite and induce afferent mechanical sensitization through NMDA receptor activation. These findings suggest that modest elevations of interstitial glutamate concentration could alter musculoskeletal pain sensitivity in humans.

  18. SDF 1-alpha (CXCL12) triggers glutamate exocytosis from astrocytes on a millisecond time scale: imaging analysis at the single-vesicle level with TIRF microscopy.

    Science.gov (United States)

    Calì, Corrado; Marchaland, Julie; Regazzi, Romano; Bezzi, Paola

    2008-07-31

    Chemokines are small chemotactic molecules widely expressed throughout the central nervous system. A number of papers, during the past few years, have suggested that they have physiological functions in addition to their roles in neuroinflammatory diseases. In this context, the best evidence concerns the CXC-chemokine stromal cell-derived factor (SDF-1alpha or CXCL12) and its receptor CXCR4, whose signalling cascade is also implicated in the glutamate release process from astrocytes. Recently, astrocytic synaptic like microvesicles (SLMVs) that express vesicular glutamate transporters (VGLUTs) and are able to release glutamate by Ca2+-dependent regulated exocytosis, have been described both in tissue and in cultured astrocytes. Here, in order to elucidate whether SDF-1alpha/CXCR4 system can participate to the brain fast communication systems, we investigated whether the activation of CXCR4 receptor triggers glutamate exocytosis in astrocytes. By using total internal reflection (TIRF) microscopy and the membrane-fluorescent styryl dye FM4-64, we adapted an imaging methodology recently developed to measure exocytosis and recycling in synaptic terminals, and monitored the CXCR4-mediated exocytosis of SLMVs in astrocytes. We analyzed the co-localization of VGLUT with the FM dye at single-vesicle level, and observed the kinetics of the FM dye release during single fusion events. We found that the activation of CXCR4 receptors triggered a burst of exocytosis on a millisecond time scale that involved the release of Ca2+ from internal stores. These results support the idea that astrocytes can respond to external stimuli and communicate with the neighboring cells via fast release of glutamate.

  19. Amperometric L-glutamate biosensor based on bacterial cell-surface displayed glutamate dehydrogenase.

    Science.gov (United States)

    Liang, Bo; Zhang, Shu; Lang, Qiaolin; Song, Jianxia; Han, Lihui; Liu, Aihua

    2015-07-16

    A novel L-glutamate biosensor was fabricated using bacteria surface-displayed glutamate dehydrogenase (Gldh-bacteria). Here the cofactor NADP(+)-specific dependent Gldh was expressed on the surface of Escherichia coli using N-terminal region of ice nucleation protein (INP) as the anchoring motif. The cell fractionation assay and SDS-PAGE analysis indicated that the majority of INP-Gldh fusion proteins were located on the surface of cells. The biosensor was fabricated by successively casting polyethyleneimine (PEI)-dispersed multi-walled carbon nanotubes (MWNTs), Gldh-bacteria and Nafion onto the glassy carbon electrode (Nafion/Gldh-bacteria/PEI-MWNTs/GCE). The MWNTs could not only significantly lower the oxidation overpotential towards NAPDH, which was the product of NADP(+) involving in the oxidation of glutamate by Gldh, but also enhanced the current response. Under the optimized experimental conditions, the current-time curve of the Nafion/Gldh-bacteria/PEI-MWNTs/GCE was performed at +0.52 V (vs. SCE) by amperometry varying glutamate concentration. The current response was linear with glutamate concentration in two ranges (10 μM-1 mM and 2-10 mM). The low limit of detection was estimated to be 2 μM glutamate (S/N=3). Moreover, the proposed biosensor is stable, specific, reproducible and simple, which can be applied to real samples detection. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Glutamate Transporters in the Blood-Brain Barrier

    DEFF Research Database (Denmark)

    Helms, Hans Christian Cederberg; Nielsen, Carsten Uhd; Waagepetersen, Helle Sønderby

    2017-01-01

    concentration of L-glutamate causes excitotoxicity. A tight control of the brain interstitial fluid L-glutamate levels is therefore imperative, in order to maintain optimal neurotransmission and to avoid such excitotoxicity. The blood-brain barrier, i.e., the endothelial lining of the brain capillaries...... cells. The mechanisms underlying transendothelial L-glutamate transport are however still not well understood. The present chapter summarizes the current knowledge on blood-brain barrier L-glutamate transporters and the suggested pathways for the brain-to-blood L-glutamate efflux....

  1. Dysfunctional TCA-Cycle Metabolism in Glutamate Dehydrogenase Deficient Astrocytes

    DEFF Research Database (Denmark)

    Nissen, Jakob D; Pajęcka, Kamilla; Stridh, Malin H

    2015-01-01

    Astrocytes take up glutamate in the synaptic area subsequent to glutamatergic transmission by the aid of high affinity glutamate transporters. Glutamate is converted to glutamine or metabolized to support intermediary metabolism and energy production. Glutamate dehydrogenase (GDH) and aspartate...... synthesis of aspartate via pyruvate carboxylation. In the absence of glucose, lactate production from glutamate via malic enzyme was lower in GDH deficient astrocytes. In conclusions, our studies reveal that metabolism via GDH serves an important anaplerotic role by adding net carbon to the TCA cycle...

  2. Microbial production of poly-γ-glutamic acid.

    Science.gov (United States)

    Sirisansaneeyakul, Sarote; Cao, Mingfeng; Kongklom, Nuttawut; Chuensangjun, Chaniga; Shi, Zhongping; Chisti, Yusuf

    2017-09-05

    Poly-γ-glutamic acid (γ-PGA) is a natural, biodegradable and water-soluble biopolymer of glutamic acid. This review is focused on nonrecombinant microbial production of γ-PGA via fermentation processes. In view of its commercial importance, the emphasis is on L-glutamic acid independent producers (i.e. microorganisms that do not require feeding with the relatively expensive amino acid L-glutamic acid to produce γ-PGA), but glutamic acid dependent production is discussed for comparison. Strategies for improving production, reducing costs and using renewable feedstocks are discussed.

  3. Inhibitors of glutamate dehydrogenase block sodium-dependent glutamate uptake in rat brain membranes

    Directory of Open Access Journals (Sweden)

    Brendan S Whitelaw

    2013-09-01

    Full Text Available We recently found evidence for anatomic and physical linkages between the astroglial Na+-dependent glutamate transporters (GLT-1/EAAT2 and GLAST/EAAT1 and mitochondria. In these same studies, we found that the glutamate dehydrogenase (GDH inhibitor, epigallocatechin-monogallate (EGCG, inhibits both glutamate oxidation and Na+-dependent glutamate uptake in astrocytes. In the present study, we extend this finding by exploring the effects of EGCG on Na+-dependent L-[3H]-glutamate (Glu uptake in crude membranes (P2 prepared from rat brain cortex. In this preparation, uptake is almost exclusively mediated by GLT-1. EGCG inhibited L-[3H]-Glu uptake in cortical membranes with an IC50 value of 230 µM. We also studied the effects of two additional inhibitors of GDH, hexachlorophene (HCP and bithionol (BTH. Both of these compounds also caused concentration-dependent inhibition of glutamate uptake in cortical membranes. Pre-incubating with HCP for up to 15 min had no greater effect than that observed with no pre-incubation, showing that the effects occur rapidly. HCP decreased the Vmax for glutamate uptake without changing the Km, consistent with a non-competitive mechanism of action. EGCG, HCP, and BTH also inhibited Na+-dependent transport of D-[3H]-aspartate (Asp, a non-metabolizable substrate, and [3H]-γ-aminobutyric acid (GABA. In contrast to the forebrain, glutamate uptake in crude cerebellar membranes (P2 is likely mediated by GLAST (EAAT1. Therefore, the effects of these compounds were examined in cerebellar membranes. In this region, none of these compounds had any effect on uptake of either L-[3H]-Glu or D-[3H]-Asp, but they all inhibited [3H]-GABA uptake. Together these studies suggest that GDH is preferentially required for glutamate uptake in forebrain as compared to cerebellum, and GDH may be required for GABA uptake as well. They also provide further evidence for a functional linkage between glutamate transport and mitochondria.

  4. Microsensors for in vivo Measurement of Glutamate in Brain Tissue

    Directory of Open Access Journals (Sweden)

    Miranda van der Zeyden

    2008-11-01

    Full Text Available Several immobilized enzyme-based electrochemical biosensors for glutamate detection have been developed over the last decade. In this review, we compare first and second generation sensors. Structures, working mechanisms, interference prevention, in vitro detection characteristics and in vivo performance are summarized here for those sensors that have successfully detected brain glutamate in vivo. In brief, first generation sensors have a simpler structure and are faster in glutamate detection. They also show a better sensitivity to glutamate during calibration in vitro. For second generation sensors, besides their less precise detection, their fabrication is difficult to reproduce, even with a semi-automatic dip-coater. Both generations of sensors can detect glutamate levels in vivo, but the reported basal levels are different. In general, second generation sensors detect higher basal levels of glutamate compared with the results obtained from first generation sensors. However, whether the detected glutamate is indeed from synaptic sources is an issue that needs further attention.

  5. Localisation of novel forms of glutamate transporters and the cystine-glutamate antiporter in the choroid plexus: Implications for CSF glutamate homeostasis

    Science.gov (United States)

    Lee, Aven; Anderson, Ashley R.; Rayfield, Andrew J.; Stevens, Melissa G.; Poronnik, Philip; Meabon, James S.; Cook, David G.; Pow, David V.

    2012-01-01

    The choroid plexus is a structure within each ventricle of the brain that is composed of fenestrated vessels surrounded by secretory epithelial cells. The epithelial cells are linked by tight junctions to create a permeability barrier. The epithelial cells are derived from neuroectoderm, and are thus defined by some authors as a subtype of macroglia. Glutamate is a tightly regulated substance in the CSF, as it is in the rest of the brain. In the brain macroglia express multiple sodium dependent and independent glutamate transporters and are the main regulators of extracellular glutamate. However, the identities of the transporters in the choroid plexus and their localisations have remained poorly defined. In this study we examined the expression and distribution of multiple splice variants of classical sodium-dependent glutamate transporters, as well as the cystine-glutamate antiporter, and the PDZ protein NHERF1, (which acts as a molecular anchor for proteins such as the glutamate transporter GLAST). We identified three forms of sodium-dependent transporters (GLAST1a, GLAST1c and GLT1b) that are expressed at the apical surface of the epithelial cells, a location that matches the distribution of NHERF1 and the cystine-glutamate antiporter. We propose that this coincident localisation of GLAST1a/GLAST1c/GLT1b and the cystine-glutamate antiporter would permit the cyclical trafficking of glutamate and thus optimise the accumulation of cystine for the formation of glutathione in the choroid plexus. PMID:21982839

  6. Neuronal Activity and Glutamate Uptake Decrease Mitochondrial Mobility in Astrocytes and Position Mitochondria Near Glutamate Transporters

    Science.gov (United States)

    Jackson, Joshua G.; O'Donnell, John C.; Takano, Hajime; Coulter, Douglas A.

    2014-01-01

    Within neurons, mitochondria are nonuniformly distributed and are retained at sites of high activity and metabolic demand. Glutamate transport and the concomitant activation of the Na+/K+-ATPase represent a substantial energetic demand on astrocytes. We hypothesized that mitochondrial mobility within astrocytic processes might be regulated by neuronal activity and glutamate transport. We imaged organotypic hippocampal slice cultures of rat, in which astrocytes maintain their highly branched morphologies and express glutamate transporters. Using time-lapse confocal microscopy, the mobility of mitochondria within individual astrocytic processes and neuronal dendrites was tracked. Within neurons, a greater percentage of mitochondria were mobile than in astrocytes. Furthermore, they moved faster and farther than in astrocytes. Inhibiting neuronal activity with tetrodotoxin (TTX) increased the percentage of mobile mitochondria in astrocytes. Mitochondrial movement in astrocytes was inhibited by vinblastine and cytochalasin D, demonstrating that this mobility depends on both the microtubule and actin cytoskeletons. Inhibition of glutamate transport tripled the percentage of mobile mitochondria in astrocytes. Conversely, application of the transporter substrate d-aspartate reversed the TTX-induced increase in the percentage of mobile mitochondria. Inhibition of reversed Na+/Ca2+ exchange also increased the percentage of mitochondria that were mobile. Last, we demonstrated that neuronal activity increases the probability that mitochondria appose GLT-1 particles within astrocyte processes, without changing the proximity of GLT-1 particles to VGLUT1. These results imply that neuronal activity and the resulting clearance of glutamate by astrocytes regulate the movement of astrocytic mitochondria and suggest a mechanism by which glutamate transporters might retain mitochondria at sites of glutamate uptake. PMID:24478345

  7. Modafinil attenuates reinstatement of cocaine seeking: role for cystine-glutamate exchange and metabotropic glutamate receptors.

    Science.gov (United States)

    Mahler, Stephen V; Hensley-Simon, Megan; Tahsili-Fahadan, Pouya; LaLumiere, Ryan T; Thomas, Charles; Fallon, Rebecca V; Kalivas, Peter W; Aston-Jones, Gary

    2014-01-01

    Modafinil may be useful for treating stimulant abuse, but the mechanisms by which it acts to do so are unknown. Indeed, a primary effect of modafinil is to inhibit dopamine transport, which typically promotes rather than inhibits motivated behavior. Therefore, we examined the role of nucleus accumbens extracellular glutamate and the group II metabotropic glutamate receptor (mGluR2/3) in modafinil effects. One group of rats was trained to self-administer cocaine for 10 days and extinguished, then given priming injections of cocaine to elicit reinstatement. Modafinil (300 mg/kg, intraperitoneal) inhibited reinstated cocaine seeking (but did not alter extinction responding by itself), and this effect was prevented by pre-treatment with bilateral microinjections of the mGluR2/3 antagonist LY-341495 (LY) into nucleus accumbens core. No reversal of modafinil effects was seen after unilateral accumbens core LY, or bilateral LY in the rostral pole of accumbens. Next, we sought to explore effects of modafinil on extracellular glutamate levels in accumbens after chronic cocaine. Separate rats were administered non-contingent cocaine, and after 3 weeks of withdrawal underwent accumbens microdialysis. Modafinil increased extracellular accumbens glutamate in chronic cocaine, but not chronic saline-pre-treated animals. This increase was prevented by reverse dialysis of cystine-glutamate exchange or voltage-dependent calcium channel antagonists. Voltage-dependent sodium channel blockade partly attenuated the increase in glutamate, but mGluR1 blockade did not. We conclude that modafinil increases extracellular glutamate in nucleus accumbens from glial and neuronal sources in cocaine-exposed rats, which may be important for its mGluR2/3-mediated antirelapse properties. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

  8. Changes in hippocampal synaptic functions and protein expression in monosodium glutamate-treated obese mice during development of glucose intolerance.

    Science.gov (United States)

    Sasaki-Hamada, Sachie; Hojo, Yuki; Koyama, Hajime; Otsuka, Hayuma; Oka, Jun-Ichiro

    2015-05-01

    Glucose is the sole neural fuel for the brain and is essential for cognitive function. Abnormalities in glucose tolerance may be associated with impairments in cognitive function. Experimental obese model mice can be generated by an intraperitoneal injection of monosodium glutamate (MSG; 2 mg/g) once a day for 5 days from 1 day after birth. MSG-treated mice have been shown to develop glucose intolerance and exhibit chronic neuroendocrine dysfunction associated with marked cognitive malfunctions at 28-29  weeks old. Although hippocampal synaptic plasticity is impaired in MSG-treated mice, changes in synaptic transmission remain unknown. Here, we investigated whether glucose intolerance influenced cognitive function, synaptic properties and protein expression in the hippocampus. We demonstrated that MSG-treated mice developed glucose intolerance due to an impairment in the effectiveness of insulin actions, and showed cognitive impairments in the Y-maze test. Moreover, long-term potentiation (LTP) at Schaffer collateral-CA1 pyramidal synapses in hippocampal slices was impaired, and the relationship between the slope of extracellular field excitatory postsynaptic potential and stimulus intensity of synaptic transmission was weaker in MSG-treated mice. The protein levels of vesicular glutamate transporter 1 and GluA1 glutamate receptor subunits decreased in the CA1 region of MSG-treated mice. These results suggest that deficits in glutamatergic presynapses as well as postsynapses lead to impaired synaptic plasticity in MSG-treated mice during the development of glucose intolerance, though it remains unknown whether impaired LTP is due to altered inhibitory transmission. It may be important to examine changes in glucose tolerance in order to prevent cognitive malfunctions associated with diabetes. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  9. Glutamate monitoring in vitro and in vivo: recent progress in the field of glutamate biosensors

    DEFF Research Database (Denmark)

    Rieben, Nathalie Ines; Rose, Nadia Cherouati; Martinez, Karen Laurence

    2009-01-01

    , and different techniques have been developed to this end. This review presents and discusses these techniques, especially the recent progress in the field of glutamate biosensors, as well as the great potential of nanotechnology in glutamate sensing. Microdialysis coupled to analytical detection techniques...... is currently the most common method for in vivo glutamate sampling. However, the recent development and improvement of enzyme-based amperometric glutamate biosensors makes them a promising alternative to microdialysis for in vivo applications, as well as valuable devices for in vitro applications in basic...... neurobiological research. Another interesting group of biosensors for glutamate are fluorescence-based glutamate biosensors, which have unsurpassed spatio-temporal resolution and are therefore important tools for investigating glutamate dynamics during signaling. Adding to this list are biosensors based on nano...

  10. Maturation of calcium-dependent GABA, glycine, and glutamate release in the glycinergic MNTB-LSO pathway.

    Directory of Open Access Journals (Sweden)

    Javier Alamilla

    Full Text Available The medial nucleus of the trapezoid body (MNTB is a key nucleus in high-fidelity temporal processing that underlies sound localization in the auditory brainstem. While the glycinergic principal cells of the MNTB project to all primary nuclei of the superior olive, during development the projection from MNTB to the lateral superior olive (LSO is of interest because this immature inhibitory projection is known to undergo tonotopic refinement during an early postnatal period, and because during this period individual MNTB terminals in the LSO transiently release glycine GABA and glutamate. Developmental changes in calcium-dependent release are understood to be required to allow various auditory nuclei to follow high frequency activity; however, little is known about maturation of calcium-dependent release in the MNTB-LSO pathway, which has been presumed to have less stringent requirements for high-fidelity temporal following. In acute brainstem slices of rats age postnatal day 1 to 15 we recorded whole-cell responses in LSO principal neurons to electrical stimulation in the MNTB in order to measure sensitivity to external calcium, the contribution of different voltage-gated calcium channel subtypes to vesicular release, and the maturation of these measures for both GABA/glycine and glutamate transmission. Our results establish that release of glutamate at MNTB-LSO synapses is calcium-dependent. Whereas no significant developmental changes were evident for glutamate release, GABA/glycine release underwent substantial changes over the first two postnatal weeks: soon after birth L-type, N-type, and P/Q-type voltage-gated calcium channels (VGCCs together mediated release, but after hearing onset P/Q-type VGCCs predominated. Blockade of P/Q-type VGCCs reduced the estimated quantal number for GABA/gly and glutamate transmission at P5-8 and the frequency of evoked miniature glycinergic events at P12-15, without apparent effects on spontaneous release of

  11. Monosodium glutamate 'allergy': menace or myth?

    Science.gov (United States)

    Williams, A N; Woessner, K M

    2009-05-01

    Monosodium glutamate (MSG) is a salt form of a non-essential amino acid commonly used as a food additive for its unique flavour enhancing qualities. Since the first description of the 'Monosodium glutamate symptom complex', originally described in 1968 as the 'Chinese restaurant syndrome', a number of anecdotal reports and small clinical studies of variable quality have attributed a variety of symptoms to the dietary ingestion of MSG. Descriptions of MSG-induced asthma, urticaria, angio-oedema, and rhinitis have prompted some to suggest that MSG should be an aetiologic consideration in patients presenting with these conditions. This review prevents a critical review of the available literature related to the possible role of MSG in the so-called 'Chinese restaurant syndrome' and in eliciting asthmatic bronchospasm, urticaria, angio-oedema, and rhinitis. Despite concerns raised by early reports, decades of research have failed to demonstrate a clear and consistent relationship between MSG ingestion and the development of these conditions.

  12. The Glutamine-Glutamate/GABA Cycle

    DEFF Research Database (Denmark)

    Walls, Anne B; Waagepetersen, Helle S; Bak, Lasse Kristoffer

    2015-01-01

    The operation of a glutamine-glutamate/GABA cycle in the brain consisting of the transfer of glutamine from astrocytes to neurons and neurotransmitter glutamate or GABA from neurons to astrocytes is a well-known concept. In neurons, glutamine is not only used for energy production and protein...... synthesis, as in other cells, but is also an essential precursor for biosynthesis of amino acid neurotransmitters. An excellent tool for the study of glutamine transfer from astrocytes to neurons is [(14)C]acetate or [(13)C]acetate and the glial specific enzyme inhibitors, i.e. the glutamine synthetase...... information about glutamine transfer. The present review will give information about glutamine trafficking and the tools used to map it as exemplified by discussions of published work employing brain cell cultures as well as intact animals. It will be documented that considerably more glutamine is transferred...

  13. Glutamate dehydrogenase (RocG) in Bacillus licheniformis WX-02: Enzymatic properties and specific functions in glutamic acid synthesis for poly-γ-glutamic acid production.

    Science.gov (United States)

    Tian, Guangming; Wang, Qin; Wei, Xuetuan; Ma, Xin; Chen, Shouwen

    2017-04-01

    Poly-γ-glutamic acid (γ-PGA), a natural biopolymer, is widely used in cosmetics, medicine, food, water treatment, and agriculture owing to its features of moisture sequestration, cation chelation, non-toxicity and biodegradability. Intracellular glutamic acid, the substrate of γ-PGA, is a limiting factor for high yield in γ-PGA production. Bacillus subtilis and Bacillus licheniformis are both important γ-PGA producing strains, and B. subtilis synthesizes glutamic acid in vivo using the unique GOGAT/GS pathway. However, little is known about the glutamate synthesis pathway in B. licheniformis. The aim of this work was to characterize the glutamate dehydrogenase (RocG) in glutamic acid synthesis from B. licheniformis with both in vivo and in vitro experiments. By re-directing the carbon flux distribution, the rocG gene deletion mutant WX-02ΔrocG produced intracellular glutamic acid with a concentration of 90ng/log(CFU), which was only 23.7% that of the wild-type WX-02 (380ng/log(CFU)). Furthermore, the γ-PGA yield of mutant WX-02ΔrocG was 5.37g/L, a decrease of 45.3% compared to the wild type (9.82g/L). In vitro enzymatic assays of RocG showed that RocG has higher affinity for 2-oxoglutarate than glutamate, and the glutamate synthesis rate was far above degradation. This is probably the first study to reveal the glutamic acid synthesis pathway and the specific functions of RocG in B. licheniformis. The results indicate that γ-PGA production can be enhanced through improving intracellular glutamic acid synthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Glutamine and glutamate as vital metabolites

    Directory of Open Access Journals (Sweden)

    Newsholme P.

    2003-01-01

    Full Text Available Glucose is widely accepted as the primary nutrient for the maintenance and promotion of cell function. This metabolite leads to production of ATP, NADPH and precursors for the synthesis of macromolecules such as nucleic acids and phospholipids. We propose that, in addition to glucose, the 5-carbon amino acids glutamine and glutamate should be considered to be equally important for maintenance and promotion of cell function. The functions of glutamine/glutamate are many, i.e., they are substrates for protein synthesis, anabolic precursors for muscle growth, they regulate acid-base balance in the kidney, they are substrates for ureagenesis in the liver and for hepatic and renal gluconeogenesis, they act as an oxidative fuel for the intestine and cells of the immune system, provide inter-organ nitrogen transport, and act as precursors of neurotransmitter synthesis, of nucleotide and nucleic acid synthesis and of glutathione production. Many of these functions are interrelated with glucose metabolism. The specialized aspects of glutamine/glutamate metabolism of different glutamine-utilizing cells are discussed in the context of glucose requirements and cell function.

  15. Synaptically evoked glutamate transporter currents in Spinal Dorsal Horn Astrocytes

    Directory of Open Access Journals (Sweden)

    Dougherty Patrick M

    2009-07-01

    Full Text Available Abstract Background Removing and sequestering synaptically released glutamate from the extracellular space is carried out by specific plasma membrane transporters that are primarily located in astrocytes. Glial glutamate transporter function can be monitored by recording the currents that are produced by co-transportation of Na+ ions with the uptake of glutamate. The goal of this study was to characterize glutamate transporter function in astrocytes of the spinal cord dorsal horn in real time by recording synaptically evoked glutamate transporter currents. Results Whole-cell patch clamp recordings were obtained from astrocytes in the spinal substantia gelatinosa (SG area in spinal slices of young adult rats. Glutamate transporter currents were evoked in these cells by electrical stimulation at the spinal dorsal root entry zone in the presence of bicuculline, strychnine, DNQX and D-AP5. Transporter currents were abolished when synaptic transmission was blocked by TTX or Cd2+. Pharmacological studies identified two subtypes of glutamate transporters in spinal astrocytes, GLAST and GLT-1. Glutamate transporter currents were graded with stimulus intensity, reaching peak responses at 4 to 5 times activation threshold, but were reduced following low-frequency (0.1 – 1 Hz repetitive stimulation. Conclusion These results suggest that glutamate transporters of spinal astrocytes could be activated by synaptic activation, and recording glutamate transporter currents may provide a means of examining the real time physiological responses of glial cells in spinal sensory processing, sensitization, hyperalgesia and chronic pain.

  16. Depletion of vesicular zinc in dorsal horn of spinal cord causes increased neuropathic pain in mice

    DEFF Research Database (Denmark)

    Jo, Seung; Danscher, Gorm; Schrøder, Henrik

    2008-01-01

    pain. The animals were then sacrificed 5 days later. The ZnT3 immunoreactivity was found to have decreased significantly in dorsal horn of fourth, fifth, and sixth lumbar segments. In parallel with the depressed ZnT3 immunoreactivity the amount of vesicular zinc decreased perceptibly in superficial...... to neuropathic pain we applied Chung's rodent pain model on BALB/c mice, and traced zinc transporter 3 (ZnT3) proteins and zinc ions with immunohistochemistry and autometallography (AMG), respectively. Under anesthesia the left fifth lumbar spinal nerve was ligated in male mice in order to produced neuropathic...... gray matters of especially layer I-IV of the same segments. The transection-induced reduction of vesicular zinc in ZEN terminals of the dorsal horn was synchronic to reduced pain threshold, as measured by von Frey method. In a separate study, we observed intensive zinc selenite precipitation in somata...

  17. Exclusion of close linkage between the synaptic vesicular monoamine transporter locus and schizophrenia spectrum disorders

    Energy Technology Data Exchange (ETDEWEB)

    Persico, A.M.; Uhl, G.R. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); Wang, Zhe Wu [Universitario Campus Bio-Medico, Rome (Italy)] [and others

    1995-12-18

    The principal brain synaptic vesicular monoamine transporter (VMAT2) is responsible for the reuptake of serotonin, dopamine, norepinephrine, epinephrine, and histamine from the cytoplasm into synaptic vesicles, thus contributing to determination of the size of releasable neurotransmitter vesicular pools. Potential involvement of VMAT2 gene variants in the etiology of schizophrenia and related disorders was tested using polymorphic VMAT2 gene markers in 156 subjects from 16 multiplex pedigrees with schizophrenia, schizophreniform, schizoaffective, and schizotypal disorders and mood incongruent psychotic depression. Assuming genetic homogeneity, complete ({theta} = 0.0) linkage to the schizophrenia spectrum was excluded under both dominant and recessive models. Allelic variants at the VMAT2 locus do not appear to provide major genetic contributions to the etiology of schizophrenia spectrum disorders in these pedigrees. 16 refs.

  18. Neuronal exosomal miRNA-dependent translational regulation of astroglial glutamate transporter GLT1.

    Science.gov (United States)

    Morel, Lydie; Regan, Melissa; Higashimori, Haruki; Ng, Seng Kah; Esau, Christine; Vidensky, Svetlana; Rothstein, Jeffrey; Yang, Yongjie

    2013-03-08

    Perisynaptic astrocytes express important glutamate transporters, especially excitatory amino acid transporter 2 (EAAT2, rodent analog GLT1) to regulate extracellular glutamate levels and modulate synaptic activation. In this study, we investigated an exciting new pathway, the exosome-mediated transfer of microRNA (in particular, miR-124a), in neuron-to-astrocyte signaling. Exosomes isolated from neuron-conditioned medium contain abundant microRNAs and small RNAs. These exosomes can be directly internalized into astrocytes and increase astrocyte miR-124a and GLT1 protein levels. Direct miR-124a transfection also significantly and selectively increases protein (but not mRNA) expression levels of GLT1 in cultured astrocytes. Consistent with our in vitro findings, intrastriatal injection of specific antisense against miR-124a into adult mice dramatically reduces GLT1 protein expression and glutamate uptake levels in striatum without reducing GLT1 mRNA levels. MiR-124a-mediated regulation of GLT1 expression appears to be indirect and is not mediated by its suppression of the putative GLT1 inhibitory ligand ephrinA3. Moreover, miR-124a is selectively reduced in the spinal cord tissue of end-stage SOD1 G93A mice, the mouse model of ALS. Subsequent exogenous delivery of miR-124a in vivo through stereotaxic injection significantly prevents further pathological loss of GLT1 proteins, as determined by GLT1 immunoreactivity in SOD1 G93A mice. Together, our study characterized a new neuron-to-astrocyte communication pathway and identified miRNAs that modulate GLT1 protein expression in astrocytes in vitro and in vivo.

  19. Vesicular noradrenaline stores in peripheral nerves of the rat and their modification by tranylcypromine.

    OpenAIRE

    Fillenz, M; Stanford, S. C.

    1981-01-01

    1 Vesicular noradrenaline stores were compared in the heart, salivary gland and vas deferens of the rat. 2 Noradrenaline storage vesicles in nerve terminals of different organs differed with respect to the amount of noradrenaline they contain in the endogenous store (content), the amount of exogenous noradrenaline they can take up from the circulation (uptake) and the amount of noradrenaline they contain when they are saturated (total storage capacity). 3 The data suggest that the vesicles in...

  20. Endoplasmosis and exoplasmosis: the evolutionary principles underlying endocytosis, exocytosis, and vesicular transport

    OpenAIRE

    Schmid, Johannes A.

    2016-01-01

    Summary Eukaryotic cells are characterized by a multicompartmental structure with a?variety of organelles. Vesicular transport between these compartments requires membrane fusion events. Based on a?membrane topology view, we conclude that there are two basic mechanisms of membrane fusion, namely where the membranes first come in contact with the cis-side (the plasmatic phase of the lipid bilayer) or with the trans-side (the extra-plasmatic face). We propose to designate trans-membrane fusion ...

  1. Neurovirulence properties of recombinant vesicular stomatitis virus vectors in non-human primates

    OpenAIRE

    Johnson, J. Erik; Nasar, Farooq; Coleman, John W.; Price, Roger E; Javadian, Ali; Draper, Kenneth; Lee, Margaret; Reilly, Patricia A.; Clarke, David K.; Hendry, R. Michael; Udem, Stephen A.

    2007-01-01

    Although vesicular stomatitis virus (VSV) neurovirulence and pathogenicity in rodents have been well studied, little is known about VSV pathogenicity in non-human primates. To address this question, we measured VSV viremia, shedding, and neurovirulence in macaques. Following intranasal inoculation, macaques shed minimal recombinant VSV (rVSV) in nasal washes for one day post-inoculation; viremia was not detected. Following intranasal inoculation of macaques, wild type (wt) VSV, rVSV, and two ...

  2. Protective efficacy of a recombinant Newcastle disease virus expressing glycoprotein of vesicular stomatitis virus in mice

    OpenAIRE

    Zhang, Minmin; Ge, Jinying; Li, Xiaofang; Chen, Weiye; Wang, Xijun; Wen, Zhiyuan; Bu, Zhigao

    2016-01-01

    Background Vesicular stomatitis virus (VSV) causes severe losses to the animal husbandry industry. In this study, a recombinant Newcastle disease virus (NDV) expressing the glycoprotein (G) of VSV (rL-VSV-G) was constructed and its pathogenicity and immune protective efficacy in mouse were evaluated. Results In pathogenicity evaluation test, the analysis of the viral distribution in mouse organs and body weight change showed that rL-VSV-G was safe in mice. In immune protection assay, the reco...

  3. Pseudotype formation of murine leukemia virus with the G protein of vesicular stomatitis virus.

    OpenAIRE

    Emi, N; Friedmann, T; Yee, J K

    1991-01-01

    Mixed infection of a cell by vesicular stomatitis virus (VSV) and retroviruses results in the production of progeny virions bearing the genome of one virus encapsidated by the envelope proteins of the other. The mechanism for the phenomenon of pseudotype formation is not clear, although specific recognition of a viral envelope protein by the nucleocapsid of an unrelated virus is presumably involved. In this study, we used Moloney murine leukemia virus (MoMLV)-based retroviral vectors encoding...

  4. Production of vesicular stomatitis virus by antigen- or mitogen-stimulated lymphocytes and continuous lymphoblastoid lines

    Energy Technology Data Exchange (ETDEWEB)

    Nowakowski, M.; Feldman, J.D.; Kano, S.; Bloom, B.R.

    1973-04-01

    The purpose of this study is to explore at the ultrastructural level the nature of the cells engaged in the production of vesicular stomatitis virus (VSV) in different lymphoid cell populations, particularly after stimulation with several different agents. Specifically, we have examined (a) lymph node cells from guinea pigs with delayed hypersensitivity activated by specific antigen, (b) murine spleen cells activated by selective B cell and T cell mitogens, and (c) cells of human and murine continuous lymphoblastoid or lymphoma lines.

  5. Efficacy study of vesicular gel containing methotrexate and menthol combination on parakeratotic rat skin model.

    Science.gov (United States)

    Nagle, Amrita; Goyal, Amit K; Kesarla, Rajesh; Murthy, Rayasa R

    2011-06-01

    Methotrexate (MTX) is indicated in the symptomatic control of severe, recalcitrant, and disabling psoriasis. The oral or parenteral route of administration causes systemic toxicity. The topical route of delivery, though, reduces systemic toxicity and has limited applicability due to restricted permeability. Liposomal and niosomal MTX topical formulations have also been investigated with limited success to achieve drug localization in the skin. Menthol has been suggested in conditions of psoriasis, in addition to its skin-penetration-enhancing effect on drugs. The present work aimed at investigating the potential benefits of combining menthol with MTX in a vesicular gel base for not only improving the penetration and dermal availability of MTX, but also to render such a formulation more effective with greater patient acceptability. MTX liposomes were prepared by thin-film hydration, and the vesicles were characterized for drug-entrapment efficiency, size, and morphology. These liposomal vesicles were incorporated in a gel base, and this vesicular gel was evaluated for transdermal drug permeation and extent of drug accumulation in the skin, using a rat skin ex vivo model. Skin histology studies were carried out to investigate any structural changes caused by the permeation enhancers. Antipsoriatic efficacy of the formulations was tested in vivo, using the rat tail model. The results indicated that the vesicular gel containing menthol could cause maximum drug retention in the skin. The skin treated with menthol had a disrupted epidermis and microcavities. The in vivo studies also ascertained the effectiveness of the formulation in inducing a normal pattern of differentiation in the rat tail skin that initially showed parakeratosis, which is also characteristic of psoriatic epidermis. These results show the potential of vesicular gel containing MTX and menthol to improve penetration into the skin and cause drug retention in skin appendages.

  6. Formation and Stability of Prebiotically Relevant Vesicular Systems in Terrestrial Geothermal Environments

    OpenAIRE

    Manesh Prakash Joshi; Anupam Samanta; Gyana Ranjan Tripathy; Sudha Rajamani

    2017-01-01

    Terrestrial geothermal fields and oceanic hydrothermal vents are considered as candidate environments for the emergence of life on Earth. Nevertheless, the ionic strength and salinity of oceans present serious limitations for the self-assembly of amphiphiles, a process that is fundamental for the formation of first protocells. Consequently, we systematically characterized the efficiency of amphiphile assembly, and vesicular stability, in terrestrial geothermal environments, both, under simula...

  7. Inhibition of skin inflammation in mice by diclofenac in vesicular carriers: liposomes, ethosomes and PEVs.

    Science.gov (United States)

    Caddeo, Carla; Sales, Octavio Diez; Valenti, Donatella; Saurí, Amparo Ruiz; Fadda, Anna Maria; Manconi, Maria

    2013-02-25

    Diclofenac-loaded phospholipid vesicles, namely conventional liposomes, ethosomes and PEVs (penetration enhancer-containing vesicles) were developed and their efficacy in TPA (phorbol ester) induced skin inflammation was examined. Vesicles were made from a cheap and unpurified mixture of phospholipids and diclofenac sodium; Transcutol P and propylene glycol were added to obtain PEVs, and ethanol to produce ethosomes. The structure and lamellar organization of the vesicle bilayer were investigated by transmission electron microscopy and small and wide angle X-ray scattering, as well as the main physico-chemical features. The formulations, along with a diclofenac solution and commercial Voltaren Emulgel, were tested in a comparative trial for anti-inflammatory efficacy on TPA-treated mice dorsal skin. Vesicles were around 100 nm, negatively charged, able to encapsulate diclofenac in good yields, and disclosed different lamellarity, as a function of the formulation composition. Vesicular formulations promoted drug accumulation and reduced the permeation. Administration of vesicular diclofenac on TPA-inflamed skin resulted in marked attenuation of oedema and leucocyte infiltration, especially using PEVs. Histology confirmed the effectiveness of vesicles, since they provided an amelioration of the tissual damage induced by TPA. The proposed approach based on vesicular nanocarriers may hold promising therapeutic value for treating a variety of inflammatory skin disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. In vitro percutaneous permeation and skin accumulation of finasteride using vesicular ethosomal carriers.

    Science.gov (United States)

    Rao, Yuefeng; Zheng, Feiyue; Zhang, Xingguo; Gao, Jianqing; Liang, Wenquan

    2008-01-01

    In order to develop a novel transdermal drug delivery system that facilitates the skin permeation of finasteride encapsulated in novel lipid-based vesicular carriers (ethosomes)finasteride ethosomes were constructed and the morphological characteristics were studied by transmission electron microscopy. The particle size, zeta potential and the entrapment capacity of ethosome were also determined. In contrast to liposomes ethosomes were of more condensed vesicular structure and they were found to be oppositely charged. Ethosomes were found to be more efficient delivery carriers with high encapsulation capacities. In vitro percutaneous permeation experiments demonstrated that the permeation of finasteride through human cadaver skin was significantly increased when ethosomes were used. The finasteride transdermal fluxes from ethosomes containing formulation (1.34 +/- 0.11 microg/cm(2)/h) were 7.4, 3.2 and 2.6 times higher than that of finasteride from aqueous solution, conventional liposomes and hydroethanolic solution respectively (P ethosomes produced a significant (P ethosomes are promising vesicular carriers for enhancing percutaneous absorption of finasteride.

  9. Spiroindolines identify the vesicular acetylcholine transporter as a novel target for insecticide action.

    Directory of Open Access Journals (Sweden)

    Ann Sluder

    Full Text Available The efficacy of all major insecticide classes continues to be eroded by the development of resistance mediated, in part, by selection of alleles encoding insecticide insensitive target proteins. The discovery of new insecticide classes acting at novel protein binding sites is therefore important for the continued protection of the food supply from insect predators, and of human and animal health from insect borne disease. Here we describe a novel class of insecticides (Spiroindolines encompassing molecules that combine excellent activity against major agricultural pest species with low mammalian toxicity. We confidently assign the vesicular acetylcholine transporter as the molecular target of Spiroindolines through the combination of molecular genetics in model organisms with a pharmacological approach in insect tissues. The vesicular acetylcholine transporter can now be added to the list of validated insecticide targets in the acetylcholine signalling pathway and we anticipate that this will lead to the discovery of novel molecules useful in sustaining agriculture. In addition to their potential as insecticides and nematocides, Spiroindolines represent the only other class of chemical ligands for the vesicular acetylcholine transporter since those based on the discovery of vesamicol over 40 years ago, and as such, have potential to provide more selective tools for PET imaging in the diagnosis of neurodegenerative disease. They also provide novel biochemical tools for studies of the function of this protein family.

  10. Influence of the preparation route on the supramolecular organization of lipids in a vesicular system.

    Science.gov (United States)

    Elizondo, Elisa; Larsen, Jannik; Hatzakis, Nikos S; Cabrera, Ingrid; Bjørnholm, Thomas; Veciana, Jaume; Stamou, Dimitrios; Ventosa, Nora

    2012-02-01

    A confocal fluorescence microscopy-based assay was used for studying the influence of the preparation route on the supramolecular organization of lipids in a vesicular system. In this work, vesicles composed of cholesterol and CTAB (1/1 mol %) or cholesterol and DOPC (2/8 mol %) and incorporating two membrane dyes were prepared by either a compressed fluid (CF)-based method (DELOS-susp) or a conventional film hydration procedure. They were subsequently immobilized and imaged individually using a confocal fluorescence microscope. Two integrated fluorescence intensities, I(dye1) and I(dye2), were assigned to each tracked vesicle, and their ratio, I(dye1)/I(dye2), was used for quantifying the degree of membrane inhomogeneity between individual vesicles within each sample. A distribution of I(dye1)/I(dye2) values was obtained for all the studied vesicular systems, indicating intrasample heterogeneity. The degree of inhomogeneity (DI) was similar for Chol/DOPC vesicles prepared by both procedures. In contrast, DI was more than double for the hydration method compared to the CF-based method in the case of Chol/CTAB vesicles, which can suffer from lipid demixing during film formation. These findings reveal a more homogeneous vesicle formation path by CFs, which warranted good homogeneity of the vesicular system, independently of the lipid mixture used. © 2011 American Chemical Society

  11. From the Cover: Glutamate antagonists limit tumor growth

    Science.gov (United States)

    Rzeski, Wojciech; Turski, Lechoslaw; Ikonomidou, Chrysanthy

    2001-05-01

    Neuronal progenitors and tumor cells possess propensity to proliferate and to migrate. Glutamate regulates proliferation and migration of neurons during development, but it is not known whether it influences proliferation and migration of tumor cells. We demonstrate that glutamate antagonists inhibit proliferation of human tumor cells. Colon adenocarcinoma, astrocytoma, and breast and lung carcinoma cells were most sensitive to the antiproliferative effect of the N-methyl-D-aspartate antagonist dizocilpine, whereas breast and lung carcinoma, colon adenocarcinoma, and neuroblastoma cells responded most favorably to the -amino-3-hydroxy-5-methyl-4-isoxazole-propionate antagonist GYKI52466. The antiproliferative effect of glutamate antagonists was Ca2+ dependent and resulted from decreased cell division and increased cell death. Morphological alterations induced by glutamate antagonists in tumor cells consisted of reduced membrane ruffling and pseudopodial protrusions. Furthermore, glutamate antagonists decreased motility and invasive growth of tumor cells. These findings suggest anticancer potential of glutamate antagonists.

  12. Depersonalization disorder may be related to glutamate receptor activation imbalance.

    Science.gov (United States)

    Pikwer, Andreas

    2011-10-01

    Low-dose ketamine administration mimics, both clinically and on gross neuroimaging, depersonalization disorder. The perceptual effects of ketamine may be due to secondary stimulation of glutamate release and lamotrigine, possibly by inhibited glutamate release, may reduce some of ketamine's so-called dissociative effects. However, lamotrigine does not seem to be useful in the treatment of depersonalization disorder. Glutamate release in prefrontal cortex is increased by subanaesthetic doses of ketamine, resulting in increased inhibition, possibly via intercalated GABAerg cells, of projections from amygdala, affecting structures critically involved in depersonalization. I speculate that, in depersonalization disorder, the increased glutamate activity in prefrontal cortex is due to intrinsic imbalance, resulting in long-term potentiation, at the postsynaptic glutamate receptors on the GABAerg interneurons while the same receptor abnormality at the synapses on the intercalated GABAerg cells of the amygdala result in long-term depression in the case of either normal or high glutamate release. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. [Determination of glutamic acid in biological material by capillary electrophoresis].

    Science.gov (United States)

    Narezhnaya, E; Krukier, I; Avrutskaya, V; Degtyareva, A; Igumnova, E A

    2015-01-01

    The conditions for the identification and determination of Glutamic acid by capillary zone electrophoresis without their preliminary derivatization have been optimized. The effect of concentration of buffer electrolyte and pH on determination of Glutamic acid has been investigated. It is shown that the 5 Mm borate buffer concentration and a pH 9.15 are optimal. Quantitative determination of glutamic acid has been carried out using a linear dependence between the concentration of the analyte and the area of the peak. The accuracy and reproducibility of the determination are confirmed by the method "introduced - found". Glutamic acid has been determined in the placenta homogenate. The duration of analysis doesn't exceed 30 minutes. The results showed a decrease in the level of glutamic acid in cases of pregnancy complicated by placental insufficiency compared with the physiological, and this fact allows to consider the level of glutamic acid as a possible marker of complicated pregnancy.

  14. Increased expression of cystine/glutamate antiporter in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Villoslada Pablo

    2011-06-01

    Full Text Available Abstract Background Glutamate excitotoxicity contributes to oligodendrocyte and tissue damage in multiple sclerosis (MS. Intriguingly, glutamate level in plasma and cerebrospinal fluid of MS patients is elevated, a feature which may be related to the pathophysiology of this disease. In addition to glutamate transporters, levels of extracellular glutamate are controlled by cystine/glutamate antiporter xc-, an exchanger that provides intracellular cystine for production of glutathione, the major cellular antioxidant. The objective of this study was to analyze the role of the system xc- in glutamate homeostasis alterations in MS pathology. Methods Primary cultures of human monocytes and the cell line U-937 were used to investigate the mechanism of glutamate release. Expression of cystine glutamate exchanger (xCT was quantified by quantitative PCR, Western blot, flow cytometry and immunohistochemistry in monocytes in vitro, in animals with experimental autoimmune encephalomyelitis (EAE, the animal model of MS, and in samples of MS patients. Results and discussion We show here that human activated monocytes release glutamate through cystine/glutamate antiporter xc- and that the expression of the catalytic subunit xCT is upregulated as a consequence of monocyte activation. In addition, xCT expression is also increased in EAE and in the disease proper. In the later, high expression of xCT occurs both in the central nervous system (CNS and in peripheral blood cells. In particular, cells from monocyte-macrophage-microglia lineage have higher xCT expression in MS and in EAE, indicating that immune activation upregulates xCT levels, which may result in higher glutamate release and contribution to excitotoxic damage to oligodendrocytes. Conclusions Together, these results reveal that increased expression of the cystine/glutamate antiporter system xc- in MS provides a link between inflammation and excitotoxicity in demyelinating diseases.

  15. Modeling of glutamic acid production by Lactobacillus plantarum MNZ

    OpenAIRE

    Zareian,Mohsen; Ebrahimpour,Afshin; Mohamed, Abdul Karim Sabo; Saari, Nazamid

    2013-01-01

    Background: L-glutamic acid, the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism acts as a precursor of γ-amino butyric acid (GABA). In the present study, culture condition for enhanced glutamic acid production by Lactobacillus plantarum MNZ was optimized and the influence of such conditions on GABA production was evaluated. Results: Results indicated that glutamic acid increased up to 3-fold (3.35) under the following condition: pH 4.5, tem...

  16. Exercise increases mitochondrial glutamate oxidation in the mouse cerebral cortex.

    Science.gov (United States)

    Herbst, Eric A F; Holloway, Graham P

    2016-07-01

    The present study investigated the impact of acute exercise on stimulating mitochondrial respiratory function in mouse cerebral cortex. Where pyruvate-stimulated respiration was not affected by acute exercise, glutamate respiration was enhanced following the exercise bout. Additional assessment revealed that this affect was dependent on the presence of malate and did not occur when substituting glutamine for glutamate. As such, our results suggest that glutamate oxidation is enhanced with acute exercise through activation of the malate-aspartate shuttle.

  17. Glutamate transporter: an unexpected target for some antibiotics.

    Science.gov (United States)

    Mao, Jianren

    2005-02-09

    Glutamate transporter (GT) plays a major role in the mechanisms of glutamate homeostasis. Can this transporter system be a therapeutic target for glutamate-mediated neurological disorders? In January's edition of Nature, Rothstein et al (2005) reports that the most commonly used class of antibiotics (beta-lactam antibiotics) such as ceftriaxone promoted the expression of GLT1 and demonstrated a functional role in both in vitro and in vivo models of glutamate neurotoxicity. These findings indicate that positive promoters of GT expression may have a unique role in neuroprotection through regulating GT expression. This is also encouraging in search for new pharmacological tools for pain management.

  18. Glutamate. Its applications in food and contribution to health.

    Science.gov (United States)

    Jinap, S; Hajeb, P

    2010-08-01

    This article reviews application of glutamate in food and its benefits and role as one of the common food ingredients used. Monosodium glutamate is one of the most abundant naturally occurring amino acids which frequently added as a flavor enhancer. It produced a unique taste that cannot be provided by other basic taste (saltiness, sourness, sweetness and bitterness), referred to as a fifth taste (umami). Glutamate serves some functions in the body as well, serving as an energy source for certain tissues and as a substrate for glutathione synthesis. Glutamate has the potential to enhance food intake in older individuals and dietary free glutamate evoked a visceral sensation from the stomach, intestine and portal vein. Small quantities of glutamate used in combination with a reduced amount of table salt during food preparation allow for far less salt to be used during and after cooking. Because glutamate is one of the most intensely studied food ingredients in the food supply and has been found safe, the Joint Expert Committee on Food Additives of the United Nations Food and Agriculture Organization and World Health Organization placed it in the safest category for food additives. Despite a widespread belief that glutamate can elicit asthma, migraine headache and Chinese Restaurant Syndrome (CRS), there are no consistent clinical data to support this claim. In addition, findings from the literature indicate that there is no consistent evidence to suggest that individuals may be uniquely sensitive to glutamate. 2010 Elsevier Ltd. All rights reserved.

  19. How Glutamate Is Managed by the Blood–Brain Barrier

    Directory of Open Access Journals (Sweden)

    Richard A. Hawkins

    2016-10-01

    Full Text Available A facilitative transport system exists on the blood–brain barrier (BBB that has been tacitly assumed to be a path for glutamate entry to the brain. However, glutamate is a non-essential amino acid whose brain content is much greater than plasma, and studies in vivo show that glutamate does not enter the brain in appreciable quantities except in those small regions with fenestrated capillaries (circumventricular organs. The situation became understandable when luminal (blood facing and abluminal (brain facing membranes were isolated and studied separately. Facilitative transport of glutamate and glutamine exists only on the luminal membranes, whereas Na+-dependent transport systems for glutamate, glutamine, and some other amino acids are present only on the abluminal membrane. The Na+-dependent cotransporters of the abluminal membrane are in a position to actively transport amino acids from the extracellular fluid (ECF into the endothelial cells of the BBB. These powerful secondary active transporters couple with the energy of the Na+-gradient to move glutamate and glutamine into endothelial cells, whereupon glutamate can exit to the blood on the luminal facilitative glutamate transporter. Glutamine may also exit the brain via separate facilitative transport system that exists on the luminal membranes, or glutamine can be hydrolyzed to glutamate within the BBB, thereby releasing ammonia that is freely diffusible. The γ-glutamyl cycle participates indirectly by producing oxoproline (pyroglutamate, which stimulates almost all secondary active transporters yet discovered in the abluminal membranes of the BBB.

  20. Strontium D-Glutamate Hexahydrate and Strontium Di(hydrogen L-glutamate) Pentahydrate

    DEFF Research Database (Denmark)

    Christgau, Stephan; Odderhede, Jette; Stahl, Kenny

    2005-01-01

    Sr(C5H7NO4)] center dot 6H(2)O, ( I), and [Sr(C5H8NO4)(2)] center dot 5H(2)O, (II), both crystallize with similar strontium - glutamate - water layers. In ( I), the neutral layers are connected through hydrogen bonds by water molecules, while in ( II), the positively charged layers are connected...

  1. Glutamate concentration in whole saliva and taste responses to monosodium glutamate in humans.

    Science.gov (United States)

    Scinska-Bienkowska, A; Wrobel, E; Turzynska, D; Bidzinski, A; Jezewska, E; Sienkiewicz-Jarosz, H; Golembiowska, K; Kostowski, W; Kukwa, A; Plaznik, A; Bienkowski, P

    2006-01-01

    It is universally accepted that saliva plays an important role in taste sensations. However, interactions between constituents of whole saliva and the five basic taste modalities are still poorly understood. The aim of the present study was to evaluate possible relationship between endogenous glutamate (Glu) levels in whole saliva and taste responses to a prototypic umami substance, monosodium glutamate (MSG; 0.03-10.0%). Rated intensity and pleasantness of MSG taste was studied in healthy volunteers divided into a high glutamate (HG) in saliva (HG; n = 19) and low glutamate in saliva (LG; n = 18) group based on the median split level of salivary Glu. The HG and LG group did not differ in terms of electrogustometric thresholds, rated intensity of the MSG samples and pleasantness of distilled water and the lower MSG concentrations (0.03-1.0%). Perceived intensity of water taste was significantly (P < 0.05) higher in the LG subjects. The LG group rated the higher MSG concentrations (3.0-10.0%) as more unpleasant (P < 0.01). The difference remained significant after controlling for a between-group difference in age. The present results suggest that individual differences in salivary Glu levels may alter hedonic responses to suprathreshold MSG concentrations.

  2. Rat odontoblasts may use glutamate to signal dentin injury.

    Science.gov (United States)

    Cho, Yi Sul; Ryu, Chang Hyun; Won, Jong Hwa; Vang, Hue; Oh, Seog Bae; Ro, Jin Young; Bae, Yong Chul

    2016-10-29

    Accumulating evidence indicates that odontoblasts act as sensor cells, capable of triggering action potentials in adjacent pulpal nociceptive axons, suggesting a paracrine signaling via a currently unknown mediator. Since glutamate can mediate signaling by non-neuronal cells, and peripheral axons may express glutamate receptors (GluR), we hypothesized that the expression of high levels of glutamate, and of sensory receptors in odontoblasts, combined with an expression of GluR in adjacent pulpal axons, is the morphological basis for odontoblastic sensory signaling. To test this hypothesis, we investigated the expression of glutamate, the thermo- and mechanosensitive ion channels transient receptor potential vanilloid 1 (TRPV1), transient receptor potential ankyrin 1 (TRPA1), and TWIK-1-related K+channel (TREK-1), and the glutamate receptor mGluR5, in a normal rat dental pulp, and following dentin injury. We also examined the glutamate release from odontoblast in cell culture. Odontoblasts were enriched with glutamate, at the level as high as in adjacent pulpal axons, and showed immunoreactivity for TRPV1, TRPA1, and TREK-1. Pulpal sensory axons adjacent to odontoblasts expressed mGluR5. Both the levels of glutamate in odontoblasts, and the expression of mGluR5 in nearby axons, were upregulated following dentin injury. The extracellular glutamate concentration was increased significantly after treating of odontoblast cell line with calcium permeable ionophore, suggesting glutamate release from odontoblasts. These findings lend morphological support to the hypothesis that odontoblasts contain glutamate as a potential neuroactive substance that may activate adjacent pulpal axons, and thus contribute to dental pain and hypersensitivity. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Identification and characterization of a bacterial glutamic peptidase

    Directory of Open Access Journals (Sweden)

    Jensen Kenneth

    2010-12-01

    Full Text Available Abstract Background Glutamic peptidases, from the MEROPS family G1, are a distinct group of peptidases characterized by a catalytic dyad consisting of a glutamate and a glutamine residue, optimal activity at acidic pH and insensitivity towards the microbial derived protease inhibitor, pepstatin. Previously, only glutamic peptidases derived from filamentous fungi have been characterized. Results We report the first characterization of a bacterial glutamic peptidase (pepG1, derived from the thermoacidophilic bacteria Alicyclobacillus sp. DSM 15716. The amino acid sequence identity between pepG1 and known fungal glutamic peptidases is only 24-30% but homology modeling, the presence of the glutamate/glutamine catalytic dyad and a number of highly conserved motifs strongly support the inclusion of pepG1 as a glutamic peptidase. Phylogenetic analysis places pepG1 and other putative bacterial and archaeal glutamic peptidases in a cluster separate from the fungal glutamic peptidases, indicating a divergent and independent evolution of bacterial and fungal glutamic peptidases. Purification of pepG1, heterologously expressed in Bacillus subtilis, was performed using hydrophobic interaction chromatography and ion exchange chromatography. The purified peptidase was characterized with respect to its physical properties. Temperature and pH optimums were found to be 60°C and pH 3-4, in agreement with the values observed for the fungal members of family G1. In addition, pepG1 was found to be pepstatin-insensitive, a characteristic signature of glutamic peptidases. Conclusions Based on the obtained results, we suggest that pepG1 can be added to the MEROPS family G1 as the first characterized bacterial member.

  4. Linking tricyclic antidepressants to ionotropic glutamate receptors.

    Science.gov (United States)

    Stoll, Laura; Gentile, Lisa

    2005-07-29

    Although tricyclic antidepressants have been in existence since the 1940s when they were discovered upon screening iminodibenzyl derivatives for other potential therapeutic uses, their mechanism of action has remained unclear [A. Goodman Gilman, T.W. Rall, A.S. Nies, P. Taylor, Goodman and Gilman's The Pharmacological Basis of Therapeutics, eighth ed., Pergamon Press, New York, 1990]. In addition to their ability to hinder the reuptake of biogenic amines, there is mounting evidence that the tricyclic antidepressants inhibit glutamate transmission. Here, intrinsic tryptophan fluorescence spectroscopy is used to document the binding of desipramine, a member of the tricyclic antidepressant family, to a well-defined extracellular glutamate binding domain (S1S2) of the GluR2 subunit of the amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. The binding is distinct from those of other known effectors of the receptor, including the endogenous sulfated neurosteroids pregnenolone sulfate and 3alpha-hydroxy-5beta-pregnan-20-one sulfate, and is consistent with a conformational change upon binding that is allosterically transmitted to the channel region of the receptor.

  5. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hemoglobin glutamer-200 (bovine). 522.1125 Section... § 522.1125 Hemoglobin glutamer-200 (bovine). (a) Specifications. Each 125 milliliter bag contains 13 grams per deciliter of polymerized hemoglobin of bovine origin in modified Lactated Ringer's Solution...

  6. Electrochemical Synthesis of Polypyrrole Layers Doped with Glutamic Ions

    NARCIS (Netherlands)

    Meteleva-Fischer, Yulia V.; Von Hauff, Elizabeth; Parisi, Juergen

    2009-01-01

    Electrochemically synthesized polypyrrole thin films doped with glutamic ions were investigated as interesting materials for potential use as molecularly selective surfaces. Pyrrole and glutamate interact in aqueous solution, resulting in the formation of a prominent band at 240 nm in the absorption

  7. A review of glutamate's role in traumatic brain injury mechanisms

    Science.gov (United States)

    Good, Cameron H.

    2013-05-01

    Glutamate is the primary excitatory neurotransmitter used by the central nervous system (CNS) for synaptic communication, and its extracellular concentration is tightly regulated by glutamate transporters located on nearby astrocytes. Both animal models and human clinical studies have demonstrated elevated glutamate levels immediately following a traumatic brain event, with the duration and severity of the rise corresponding to prognosis. This rise in extracellular glutamate likely results from a combination of excessive neurotransmitter release from damaged neurons and down regulation of uptake mechanisms in local astrocytes. The immediate results of a traumatic event can lead to necrotic tissue in severely injured regions, while prolonged increases in excitatory transmission can cause secondary excitotoxic injury through activation of delayed apoptotic pathways. Initial TBI animal studies utilized a variety of broad glutamate receptor antagonists to successfully combat secondary injury mechanisms, but unfortunately this same strategy has proven inconclusive in subsequent human trials due to deleterious side effects and heterogeneity of injuries. More recent treatment strategies have utilized specific glutamate receptor subunit antagonists in an effort to minimize side effects and have shown promising results. Future challenges will be detecting the concentration and kinetics of the glutamate rise following injury, determining which patient populations could benefit from antagonist treatment based on their extracellular glutamate concentrations and when drugs should be administered to maximize efficacy.

  8. Surface grafting of poly(L-glutamates). 3. Block copolymerization

    NARCIS (Netherlands)

    Wieringa, RH; Siesling, EA; Werkman, PJ; Vorenkamp, EJ; Schouten, AJ

    2001-01-01

    This paper describes for the first time the synthesis of surface-grafted AB-block copolypeptides, consisting of poly(gamma -benzyl L-glutamate) (PBLG) as the A-block and poly(gamma -methyl L-glutamate) (PMLG) as the B-block. Immobilized primary amine groups of (,gamma -aminopropyl)triethoxysilane

  9. changes in activities of enzymes of glutamate metabolism in rat ...

    African Journals Online (AJOL)

    regions of brain under sub-acute dosing. Glutamine Synthetase. Glutamine synthetase converts glutamate into glutamine, and glutamine levels in neural tissues help in the m~intenance of glutamate concentration for its general .. function as an amino acid as well as for the neurotransmitter poo! (Shank and. Aprison, 1981 ).

  10. Glutamate Efflux at the Blood-Brain Barrier

    DEFF Research Database (Denmark)

    Cederberg-Helms, Hans Christian; Uhd-Nielsen, Carsten; Brodin, Birger

    2014-01-01

    L-Glutamate is considered the most important excitatory amino acid in the mammalian brain. Strict control of its concentration in the brain interstitial fluid is important to maintain neurotransmission and avoid excitotoxicity. The role of astrocytes in handling L-glutamate transport and metaboli...

  11. Some Properties of Glutamate Dehydrogenase from the Marine Red ...

    African Journals Online (AJOL)

    Keywords: ammonia assimilation, glutamate dehydrogenase, GDH, Gracilaria sordida, red alga, enzyme activity. Glutamate ... NAD-/NADP- and NADH-/ NADPH-dependent activities were the order of 11:1 and 1:1.8, respectively. The pH optima for ... This work is licensed under a Creative Commons Attribution 3.0 License.

  12. Study on soluble expression of glutamate dehydrogenase from tea ...

    African Journals Online (AJOL)

    Yomi

    2012-03-20

    Mar 20, 2012 ... Glutamate dehydrogenase (GDH; EC1.4.1.2) catalyses the reversible amination of 2-oxoglutarate for the synthesis of glutamate using ... CsGDH2 was predominantly found in insoluble bodies and no soluble protein was detected by either .... phosphatase (TAP) to remove the 50 cap structure from intact full-.

  13. Dietary glutamate will not affect pain in fibromyalgia

    NARCIS (Netherlands)

    Geenen, R.; Janssens, E.L.; Jacobs, J.W.G.; Staveren, van W.A.

    2004-01-01

    Injection of glutamate into the masseter muscle has been suggested-to evoke an increase in intensity of and sensitivity to pain. A case study showed that a diet low in monosodium glutamate (MSG) might accomplish pain relief in fibromyalgia (FM). To clarify the possible pain-modulating effect of

  14. Histochemical Studies of the Effects of Monosodium Glutamate on ...

    African Journals Online (AJOL)

    Background: Monosodium glutamate (MSG) is a commonly used food additive and there is growing concern that excitotoxins such as MSG play a critical role in the development of several hepatic disorders. Objectives: The histochemical effect of monosodium glutamate was investigated on the liver of adult Wistar rats.

  15. Microscopic picture of the aqueous solvation of glutamic acid

    NARCIS (Netherlands)

    Leenders, E.J.M.; Bolhuis, P.G.; Meijer, E.J.

    2008-01-01

    We present molecular dynamics simulations of glutamic acid and glutamate solvated in water, using both density functional theory (DFT) and the Gromos96 force field. We focus on the microscopic aspects of the solvation−particularly on the hydrogen bond structures and dynamics−and investigate the

  16. Amiodarone reduces depolarization-evoked glutamate release from hippocampual synaptosomes

    Directory of Open Access Journals (Sweden)

    Chia Yu Chang

    2017-03-01

    Full Text Available Decreased brain glutamate level has emerged as a new therapeutic approach for epilepsy. This study investigated the effect and mechanism of amiodarone, an anti-arrhythmic drug with antiepileptic activity, on glutamate release in the rat hippocampus. In a synaptosomal preparation, amiodarone reduced 4-aminopyridine-evoked Ca2+-dependent glutamate release and cytosolic Ca2+ concentration elevation. Amiodarone did not affect the 4-aminopyridine-evoked depolarization of the synaptosomal membrane potential or the Na+ channel activator veratridine-evoked glutamate release, indicating that the amiodarone-mediated inhibition of glutamate release is not caused by a decrease in synaptosomal excitability. The inhibitory effect of amiodarone on 4-aminopyridine-evoked glutamate release was markedly decreased in synaptosomes pretreated with the Cav2.2 (N-type and Cav2.1 (P/Q-type channel blocker ω-conotoxin MVIIC, the calmodulin antagonists W7 and calmidazolium, or the protein kinase A inhibitors H89 and KT5720. However, the intracellular Ca2+-release inhibitors dantrolene and CGP37157 had no effect on the amiodarone-mediated inhibition of glutamate release. Furthermore, amiodarone reduced the frequency of miniature excitatory postsynaptic currents without affecting their amplitude in hippocampal slices. Our data suggest that amiodarone reduces Ca2+ influx through N- and P/Q-type Ca2+ channels, subsequently reducing the Ca2+-calmodulin/protein kinase A cascade to inhibit the evoked glutamate release from rat hippocampal nerve terminals.

  17. Histological Studies of the Effects of Monosodium Glutamate on the ...

    African Journals Online (AJOL)

    Background: Monosodium glutamate (MSG) is a commonly used food additive and there is growing concern that this may play a critical role in the aethiopathogenesis of anovulatory infertility. Objectives: The effect of monosodium glutamate (MSG) used as food additive on the ovaries of adult Wistar rat was investigated.

  18. Coxiella burnetii effector protein subverts clathrin-mediated vesicular trafficking for pathogen vacuole biogenesis

    Science.gov (United States)

    Larson, Charles L.; Beare, Paul A.; Howe, Dale; Heinzen, Robert A.

    2013-01-01

    Successful macrophage colonization by Coxiella burnetii, the cause of human Q fever, requires pathogen-directed biogenesis of a large, growth-permissive parasitophorous vacuole (PV) with phagolysosomal characteristics. The vesicular trafficking pathways co-opted by C. burnetii for PV development are poorly defined; however, it is predicted that effector proteins delivered to the cytosol by a defective in organelle trafficking/intracellular multiplication (Dot/Icm) type 4B secretion system are required for membrane recruitment. Here, we describe involvement of clathrin-mediated vesicular trafficking in PV generation and the engagement of this pathway by the C. burnetii type 4B secretion system substrate Coxiella vacuolar protein A (CvpA). CvpA contains multiple dileucine [DERQ]XXXL[LI] and tyrosine (YXXΦ)-based endocytic sorting motifs like those recognized by the clathrin adaptor protein (AP) complexes AP1, AP2, and AP3. A C. burnetii ΔcvpA mutant exhibited significant defects in replication and PV development, confirming the importance of CvpA in infection. Ectopically expressed mCherry-CvpA localized to tubular and vesicular domains of pericentrosomal recycling endosomes positive for Rab11 and transferrin receptor, and CvpA membrane interactions were lost upon mutation of endocytic sorting motifs. Consistent with CvpA engagement of the endocytic recycling system, ectopic expression reduced uptake of transferrin. In pull-down assays, peptides containing CvpA-sorting motifs and full-length CvpA interacted with AP2 subunits and clathrin heavy chain. Furthermore, depletion of AP2 or clathrin by siRNA treatment significantly inhibited C. burnetii replication. Thus, our results reveal the importance of clathrin-coated vesicle trafficking in C. burnetii infection and define a role for CvpA in subverting these transport mechanisms. PMID:24248335

  19. A putative vesicular transporter expressed in Drosophila mushroom bodies that mediates sexual behavior may define a neurotransmitter system.

    Science.gov (United States)

    Brooks, Elizabeth S; Greer, Christina L; Romero-Calderón, Rafael; Serway, Christine N; Grygoruk, Anna; Haimovitz, Jasmine M; Nguyen, Bac T; Najibi, Rod; Tabone, Christopher J; de Belle, J Steven; Krantz, David E

    2011-10-20

    Vesicular transporters are required for the storage of all classical and amino acid neurotransmitters in synaptic vesicles. Some neurons lack known vesicular transporters, suggesting additional neurotransmitter systems remain unidentified. Insect mushroom bodies (MBs) are critical for several behaviors, including learning, but the neurotransmitters released by the intrinsic Kenyon cells (KCs) remain unknown. Likewise, KCs do not express a known vesicular transporter. We report the identification of a novel Drosophila gene portabella (prt) that is structurally similar to known vesicular transporters. Both larval and adult brains express PRT in the KCs of the MBs. Additional PRT cells project to the central complex and optic ganglia. prt mutation causes an olfactory learning deficit and an unusual defect in the male's position during copulation that is rescued by expression in KCs. Because prt is expressed in neurons that lack other known vesicular transporters or neurotransmitters, it may define a previously unknown neurotransmitter system responsible for sexual behavior and a component of olfactory learning. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Production of poly-γ-glutamic acid by a thermotolerant glutamate-independent strain and comparative analysis of the glutamate dependent difference.

    Science.gov (United States)

    Zeng, Wei; Chen, Guiguang; Guo, Ye; Zhang, Bin; Dong, Mengna; Wu, Yange; Wang, Jun; Che, Zhiqun; Liang, Zhiqun

    2017-11-25

    Poly-γ-glutamic acid (γ-PGA) is a promising microbial polymer with wide applications in industry, agriculture and medicine. In this study, a novel glutamate-independent γ-PGA producing strain with thermotolerant characteristics was isolated and identified as Bacillus subtilis GXG-5, then its product was also characterized. The fermentation process was optimized by single-factor tests, and results showed that high temperature (50 °C) was especially suitable for the γ-PGA production by GXG-5. The γ-PGA yield reached 19.50 ± 0.75 g/L with substrate conversion efficiency of 78% at 50 °C in 10 L fermentor. Comparison of GXG-5 and GXA-28 (glutamate-dependent strain) under respective optimal fermentation conditions, the γ-PGA yield of GXG-5 was 19.0% higher than that of GXA-28, and GXG-5 was also superior to GXA-28 in the availability of carbon sources and substrates. Furthermore, the glutamate dependent difference between GXA-28 and GXG-5 was analyzed by genomic sequencing, results indicated that genes related to the glutamate dependent difference mainly involved in carbohydrate transport and metabolism and amino acid metabolism, and 13 genes related to γ-PGA synthesis were mutated in GXG-5. This study provided a potential glutamate-independent strain to replace glutamate-dependent strain for γ-PGA production, and shared novel information for understanding the glutamate dependent difference at the genomic level.

  1. Prefrontal changes in the glutamate-glutamine cycle and neuronal/glial glutamate transporters in depression with and without suicide.

    Science.gov (United States)

    Zhao, J; Verwer, R W H; van Wamelen, D J; Qi, X-R; Gao, S-F; Lucassen, P J; Swaab, D F

    2016-11-01

    There are indications for changes in glutamate metabolism in relation to depression or suicide. The glutamate-glutamine cycle and neuronal/glial glutamate transporters mediate the uptake of the glutamate and glutamine. The expression of various components of the glutamate-glutamine cycle and the neuronal/glial glutamate transporters was determined by qPCR in postmortem prefrontal cortex. The anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC) were selected from young MDD patients who had committed suicide (MDD-S; n = 17), from MDD patients who died of non-suicide related causes (MDD-NS; n = 7) and from matched control subjects (n = 12). We also compared elderly depressed patients who had not committed suicide (n = 14) with matched control subjects (n = 22). We found that neuronal located components (EAAT3, EAAT4, ASCT1, SNAT1, SNAT2) of the glutamate-glutamine cycle were increased in the ACC while the astroglia located components (EAAT1, EAAT2, GLUL) were decreased in the DLPFC of MDD-S patients. In contrast, most of the components in the cycle were increased in the DLPFC of MDD-NS patients. In conclusion, the glutamate-glutamine cycle - and thus glutamine transmission - is differentially affected in depressed suicide patients and depressed non-suicide patients in an area specific way. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Radiation inactivation analysis of fusion and hemolysis by vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Bundo-Morita, K.; Gibson, S.; Lenard, J.

    1988-04-01

    Radiation inactivation analysis was used to determine the size of the functional unit responsible for fusion of vesicular stomatitis virus (VSV) with cardiolipin or phosphatidylcholine-phosphatidylethanolamine (1:1) liposomes, and for VSV-induced hemolysis. When radiation-insensitive background values were subtracted, the calculated functional units for all three activities were similar, ranging from 866 to 957 kDa, equivalent to about 15 G protein molecules. This is in striking contrast to results of similar studies with influenza and Sendai viruses, in which the functional unit corresponded in size to a single fusion protein monomer, and suggests that VSV fusion may occur by a different mechanism.

  3. Initiation and Direction of RNA Transcription by Vesicular Stomatitis Virus Virion Transcriptase

    Science.gov (United States)

    Roy, Polly; Bishop, D. H. L.

    1973-01-01

    The initiation of RNA transcription by the virion-bound RNA transcriptase of vesicular stomatitis virus has been examined. Multiple initiation sequences have been observed, two of which have been characterized (pppApCpGp... and pppGpCp...) suggestive of a transcription process which can start at different sites along the template RNA. By the use of sequential labeling techniques and exonucleases, it has been determined that there is a 5′ to 3′ direction of product RNA synthesis. PMID:4349490

  4. Vesicular Stomatitis Virus Infection Promotes Immune Evasion by Preventing NKG2D-Ligand Surface Expression

    DEFF Research Database (Denmark)

    Jensen, Helle; Andresen, Lars; Nielsen, Jens

    2011-01-01

    Vesicular stomatitis virus (VSV) has recently gained attention for its oncolytic ability in cancer treatment. Initially, we hypothesized that VSV infection could increase immune recognition of cancer cells through induction of the immune stimulatory NKG2D-ligands. Here we show that VSV infection......D-ligand expression at an early post-transcriptional level. Our results show that VSV possess an escape mechanism, which could affect the immune recognition of VSV infected cancer cells. This may also have implications for immune recognition of cancer cells after combined treatment with VSV...

  5. ANTICUERPOS CONTRA EL VIRUS DE ESTOMATITIS VESICULAR EN HUANGANAS (Tayassu pecari) EN MADRE DE DIOS, PERÚ

    OpenAIRE

    Carruitero H., Susan; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Rivera G., Hermelinda; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Ramírez V., Mercy; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; More B., Juan; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima.; Zúñiga H., Alfonso; Proyecto ÁREAS–Amazonía de la World Wildlife Fund (WWF-Peru); Romero S., Mónica; Proyecto ÁREAS–Amazonía de la World Wildlife Fund (WWF-Peru)

    2013-01-01

    El objetivo del presente estudio fue determinar la presencia de anticuerpos neutralizantes contra los serotipos New Jersey (NJ) e Indiana subtipo 1 (IND-1) del virus Estomatitis Vesicular (VEV) en huanganas (Tayassu pecari) de vida libre de las localidades de Boca de Manu (n=30), Concesión para la Conservación Los Amigos (n=10) y La Reserva Nacional Tambopata/Parque Nacional Bahuaja Sonene (n=48) en el departamento de Madre de Dios. La presencia de anticuerpos contra el VEV fue determinado me...

  6. MEJORAMIENTO DE LA PRODUCCIÓN DE UNA VACUNA OLEOSA CONTRA ESTOMATITIS VESICULAR BIVALENTE

    OpenAIRE

    Arbeláez, Gustavo; Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Cra. 7 Nº 43 - 82, Bogotá; Mondragón, Nestor; Empresa Colombiana de Productos Veterinarios Vecol S.A., Bogotá; Turriago, Clara; Empresa Colombiana de Productos Veterinarios Vecol S.A., Bogotá; Mora, Nelson; Empresa Colombiana de Productos Veterinarios Vecol S.A., Bogotá; Méndez, María; Empresa Colombiana de Productos Veterinarios Vecol S.A., Bogotá

    2008-01-01

    El presente estudio calculó diferentes MI (Multiplicidad de Infección) para la producción de cultivos industriales de virus de Estomatitis Vesicular (EV) y evaluó el efecto de la cantidad de glicoproteína G en la inducción de respuesta de anticuerpos neutralizantes contra el virus de EV en cobayos inmunizados con una vacuna oleosa bivalente (Indiana (I) y New Jersey (NJ)). Al establecer el MI más eficiente se logró mejorar la cinética de infección de los cultivos industriales disminuyendo los...

  7. The Effects of Vesicular-Arbuscular Mycorrhizae on the Plant Growth and Nutrient Uptake of Cucumber

    OpenAIRE

    ÇIĞŞAR, Sibel; Sari, Nebahat

    2014-01-01

    This study was conducted to investigate the effect of vesicular-arbuscular (VA) mycorrhizae on plant growth of cucumber. Yayla F 1 seeds were sown in sterile and non-sterile growing medium (organic manure:soil:mix of sand; v:v:v 1:1:1). The mix inoculum of Glomus mosseaand Glomus fasciculatumspores (10 g/plant) was placed 5 cm below the cucumber seed before sowing. In order to investigate the effects of VA mycorrhizae on plant growth, plant height, diameter, number of nodes were measured ...

  8. The role of glutamate and its receptors in autism and the use of glutamate receptor antagonists in treatment

    Science.gov (United States)

    Rojas, Donald C.

    2014-01-01

    Glutamate is the major excitatory neurotransmitter in the brain and may be a key neurotransmitter involved in autism. Literature pertaining to glutamate and autism or related disorders (e.g., Fragile X syndrome) is reviewed in this article. Interest in glutamatergic dysfunction in autism is high due to increasing convergent evidence implicating the system in the disorder from peripheral biomarkers, neuroimaging, protein expression, genetics and animal models. Currently, there are no pharmaceutical interventions approved for autism that address glutamate deficits in the disorder. New treatments related to glutamatergic neurotransmission, however, are emerging. In addition, older glutamate-modulating medications with approved indications for use in other disorders are being investigated for re-tasking as treatments for autism. This review presents evidence in support of glutamate abnormalities in autism and the potential for translation into new treatments for the disorder. PMID:24752754

  9. Role of spinal cord glutamate transporter during normal sensory transmission and pathological pain states

    Directory of Open Access Journals (Sweden)

    Stephens Robert L

    2005-10-01

    Full Text Available Abstract Glutamate is a neurotransmitter critical for spinal excitatory synaptic transmission and for generation and maintenance of spinal states of pain hypersensitivity via activation of glutamate receptors. Understanding the regulation of synaptically and non-synaptically released glutamate associated with pathological pain is important in exploring novel molecular mechanisms and developing therapeutic strategies of pathological pain. The glutamate transporter system is the primary mechanism for the inactivation of synaptically released glutamate and the maintenance of glutamate homeostasis. Recent studies demonstrated that spinal glutamate transporter inhibition relieved pathological pain, suggesting that the spinal glutamate transporter might serve as a therapeutic target for treatment of pathological pain. However, the exact function of glutamate transporter in pathological pain is not completely understood. This report will review the evidence for the role of the spinal glutamate transporter during normal sensory transmission and pathological pain conditions and discuss potential mechanisms by which spinal glutamate transporter is involved in pathological pain.

  10. Poly(γ-glutamic acid), coagulation? Anticoagulation?

    Science.gov (United States)

    Xu, Tingting; Peng, Fang; Zhang, Tao; Chi, Bo; Xu, Hong; Mao, Chun; Feng, Shuaihui

    2016-11-01

    Poly(γ-glutamic acid) (γ-PGA) powder was usually used as hemostatic agent because of its excellent physical properties of water-absorption and water-locking. However, if γ-PGA absorbs enough water, how about its blood compatibility? Here, the other side of the coin was investigated. The anticoagulant properties of γ-PGA were characterized by in vitro coagulation tests, hemolytic assay, platelet adhesion, and platelet activation. Moreover, cytotoxicity experiments of γ-PGA were also carried out by MTT assay. Results indicated that the sufficient water-absorbed γ-PGA has good anticoagulant property and non-cytotoxicity. It means γ-PGA has good anticoagulant property, non-cytotoxicity. If γ-PGA has absorbed enough water, it can be used as an anticoagulation biomaterial. With double effects (coagulation and anticoagulation), the γ-PGA with desirable bioproperties can be readily tailored to cater to various biomedical applications.

  11. Calcium regulates glutamate dehydrogenase and poly-γ-glutamic acid synthesis in Bacillus natto.

    Science.gov (United States)

    Meng, Yonghong; Dong, Guiru; Zhang, Chen; Ren, Yuanyuan; Qu, Yuling; Chen, Weifeng

    2016-04-01

    To study the effect of Ca(2+) on glutamate dehydrogenase (GDH) and its role in poly-γ-glutamic acid (γ-PGA) synthesis in Bacillus natto HSF 1410. When the concentration of Ca(2+) varied from 0 to 0.1 g/l in the growth medium of B. natto HSF 1410, γ-PGA production increased from 6.8 to 9.7 g/l, while GDH specific activity and NH4Cl consumption improved from 183 to 295 U/mg and from 0.65 to 0.77 g/l, respectively. GDH with α-ketoglutarate as substrate primarily used NADPH as coenzyme with a K m of 0.08 mM. GDH was responsible for the synthesis of endogenous glutamate. The specific activity of GDH remained essentially unchanged in the presence of CaCl2 (0.05-0.2 g/l) in vitro. However, the specific activity of GDH and its expression was significantly increased by CaCl2 in vivo. Therefore, the regulation of GDH and PGA synthesis by Ca(2+) is an intracellular process. Calcium regulation may be an effective approach for producing γ-PGA on an industrial scale.

  12. Genomic analyses of gas (nitric oxide and carbon monoxide) and small molecule transmitter (acetylcholine, glutamate and GABA) signaling systems in Daphnia pulex.

    Science.gov (United States)

    McCoole, Matthew D; D'Andrea, Brandon T; Baer, Kevin N; Christie, Andrew E

    2012-06-01

    Diffusible gasses and small molecule transmitters are classes of compounds used by neurons and other cell types for local and hormonal signaling. In crustaceans, there is evidence for the neuronal production of the gasses nitric oxide (NO) and carbon monoxide (CO), as well as the small molecule transmitters acetylcholine, glutamate and GABA. While much is known about the physiological roles played by these molecules in crustaceans, little is known about them at the molecular level. Here, we have mined the genome of Daphnia pulex for genes encoding the biosynthetic enzymes, receptors and transporters necessary for establishing each of these transmitter systems. The biosynthetic enzyme genes identified included nitric oxide synthase, heme oxygenase, choline acetyltransferase, glutaminase and glutamic acid decarboxylase. Genes encoding several transporters (e.g. vesicular acetylcholine transporter) were also characterized, as were ones involved in transmitter degradation/recycling (e.g. acetylcholine esterase); genes encoding receptors for NO and CO (i.e. soluble guanylyl cyclase), and for each small molecule transmitter (both ionotropic and metabotropic receptors for each compound) were identified. These data provide the first molecular descriptions of gas and small molecule transmitter signaling systems in D. pulex, and provide frameworks for future molecular, anatomical and physiological investigations of them in Daphnia. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Role of aminotransferases in glutamate metabolism of human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ellinger, James J. [University of Wisconsin-Madison, Department of Biochemistry (United States); Lewis, Ian A. [Princeton University, Lewis-Sigler Institute for Integrative Genomics (United States); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, Department of Biochemistry (United States)

    2011-04-15

    Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from {alpha}-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional {sup 1}H-{sup 13}C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

  14. Posttranslational Modification Biology of Glutamate Receptors and Drug Addiction

    Directory of Open Access Journals (Sweden)

    Li-Min eMao

    2011-03-01

    Full Text Available Posttranslational covalent modifications of glutamate receptors remain a hot topic. Early studies have established that this family of receptors, including almost all ionotropic and metabotropic glutamate receptor subtypes, undergoes active phosphorylation at serine, threonine, or tyrosine residues on their intracellular domains. Recent evidence identifies several glutamate receptor subtypes to be direct substrates for palmitoylation at cysteine residues. Other modifications such as ubiquitination and sumoylation at lysine residues also occur to certain glutamate receptors. These modifications are dynamic and reversible in nature and are regulatable by changing synaptic inputs. The regulated modifications significantly impact the receptor in many ways, including interrelated changes in biochemistry (synthesis, subunit assembling and protein-protein interactions, subcellular redistribution (trafficking, endocytosis, synaptic delivery and clustering, and physiology, usually associated with changes in synaptic plasticity. Glutamate receptors are enriched in the striatum and cooperate closely with dopamine to regulate striatal signaling. Emerging evidence shows that modification processes of striatal glutamate receptors are sensitive to addictive drugs, such as psychostimulants (cocaine and amphetamines. Altered modifications are believed to be directly linked to enduring receptor/synaptic plasticity and drug-seeking. This review summarizes several major types of modifications of glutamate receptors and analyzes the role of these modifications in striatal signaling and in the pathogenesis of psychostimulant addiction.

  15. Regulation of acetylcholine receptor clustering by ADF/cofilin-directed vesicular trafficking.

    Science.gov (United States)

    Lee, Chi Wai; Han, Jianzhong; Bamburg, James R; Han, Liang; Lynn, Rachel; Zheng, James Q

    2009-07-01

    Postsynaptic receptor localization is crucial for synapse development and function, but the underlying cytoskeletal mechanisms remain elusive. Using Xenopus neuromuscular junctions as a model, we found that actin depolymerizing factor (ADF)/cofilin regulated actin-dependent vesicular trafficking of acetylcholine receptors (AChRs) to the postsynaptic membrane. Active ADF/cofilin was concentrated in small puncta adjacent to AChR clusters and was spatiotemporally correlated with the formation and maintenance of surface AChR clusters. Notably, increased actin dynamics, vesicular markers and intracellular AChRs were all enriched at the sites of ADF/cofilin localization. Furthermore, a substantial amount of new AChRs was detected at these ADF/cofilin-enriched sites. Manipulation of either ADF/cofilin activity through its serine-3 phosphorylation or ADF/cofilin localization via 14-3-3 proteins markedly attenuated AChR insertion and clustering. These results suggest that spatiotemporally restricted ADF/cofilin-mediated actin dynamics regulate AChR trafficking during the development of neuromuscular synapses.

  16. Ethosomes: versatile vesicular carriers for efficient transdermal delivery of therapeutic agents.

    Science.gov (United States)

    Pandey, Vikas; Golhani, Dilip; Shukla, Rajesh

    2015-12-01

    Delivery across skin is attractive due to its easy accessibility. However, drug delivery across skin is still a challenge in biomedical sciences. Over the past few decades, various successful novel devices and techniques have emerged to optimize drug delivery across skin whose obstructing behavior constricts entry of most of the therapeutic agents. Inability of various conventional vesicular formulations, e.g. liposomes to pass through the tapered (>30 nm) intercellular channels of stratum corneum, rendered invention of some lipid based vesicular carrier systems such as ethosomes which consist of phospholipid, ethanol and water. Ethosomes are non-invasive delivery carriers that enable drugs to reach the deep skin layers and/or the systemic circulation. In spite of their sophistication in conceptuality, they are exemplified by easiness in their preparation, safety and efficacy - a combination that can highly inflate their application. This review attempts to describe all aspects of ethosomes including roles and upshots of different excipients, various methods of preparation and characterizations, research reports on various drug deliveries, patent reports and future prospects.

  17. Hitchhiking vesicular transport routes to the vacuole: Amyloid recruitment to the Insoluble Protein Deposit (IPOD).

    Science.gov (United States)

    Kumar, Rajesh; Neuser, Nicole; Tyedmers, Jens

    2017-03-04

    Sequestration of aggregates into specialized deposition sites occurs in many species across all kingdoms of life ranging from bacteria to mammals and is commonly believed to have a cytoprotective function. Yeast cells possess at least 3 different spatially separated deposition sites, one of which is termed "Insoluble Protein Deposit (IPOD)" and harbors amyloid aggregates. We have recently discovered that recruitment of amyloid aggregates to the IPOD uses an actin cable based recruitment machinery that also involves vesicular transport. 1 Here we discuss how different proteins known to be involved in vesicular transport processes to the vacuole might act to guide amyloid aggregates to the IPOD. These factors include the Myosin V motor protein Myo2 involved in transporting vacuolar vesicles along actin cables, the transmembrane protein Atg9 involved in the recruitment of large precursor hydrolase complexes to the vacuole, the phosphatidylinositol/ phosphatidylcholine (PI/PC) transfer protein Sec 14 and the SNARE chaperone Sec 18. Furthermore, we present new data suggesting that the yeast dynamin homolog Vps1 is also crucial for faithful delivery of the amyloid model protein PrD-GFP to the IPOD. This is in agreement with a previously identified role for Vps1 in recruitment of heat-denatured aggregates to a perivacuolar deposition site. 2.

  18. Vesicular calcium regulates coat retention, fusogenicity, and size of pre-Golgi intermediates.

    Science.gov (United States)

    Bentley, Marvin; Nycz, Deborah C; Joglekar, Ashwini; Fertschai, Ismene; Malli, Roland; Graier, Wolfgang F; Hay, Jesse C

    2010-03-15

    The significance and extent of Ca(2+) regulation of the biosynthetic secretory pathway have been difficult to establish, and our knowledge of regulatory relationships integrating Ca(2+) with vesicle coats and function is rudimentary. Here, we investigated potential roles and mechanisms of luminal Ca(2+) in the early secretory pathway. Specific depletion of luminal Ca(2+) in living normal rat kidney cells using cyclopiazonic acid (CPA) resulted in the extreme expansion of vesicular tubular cluster (VTC) elements. Consistent with this, a suppressive role for vesicle-associated Ca(2+) in COPII vesicle homotypic fusion was demonstrated in vitro using Ca(2+) chelators. The EF-hand-containing protein apoptosis-linked gene 2 (ALG-2), previously implicated in the stabilization of sec31 at endoplasmic reticulum exit sites, inhibited COPII vesicle fusion in a Ca(2+)-requiring manner, suggesting that ALG-2 may be a sensor for the effects of vesicular Ca(2+) on homotypic fusion. Immunoisolation established that Ca(2+) chelation inhibits and ALG-2 specifically favors residual retention of the COPII outer shell protein sec31 on pre-Golgi fusion intermediates. We conclude that vesicle-associated Ca(2+), acting through ALG-2, favors the retention of residual coat molecules that seem to suppress membrane fusion. We propose that in cells, these Ca(2+)-dependent mechanisms temporally regulate COPII vesicle interactions, VTC biogenesis, cargo sorting, and VTC maturation.

  19. GLTP mediated non-vesicular GM1 transport between native membranes.

    Directory of Open Access Journals (Sweden)

    Ines Lauria

    Full Text Available Lipid transfer proteins (LTPs are emerging as key players in lipid homeostasis by mediating non-vesicular transport steps between two membrane surfaces. Little is known about the driving force that governs the direction of transport in cells. Using the soluble LTP glycolipid transfer protein (GLTP, we examined GM1 (monosialotetrahexosyl-ganglioside transfer to native membrane surfaces. With artificial GM1 donor liposomes, GLTP can be used to increase glycolipid levels over natural levels in either side of the membrane leaflet, i.e., external or cytosolic. In a system with native donor- and acceptor-membranes, we find that GLTP balances highly variable GM1 concentrations in a population of membranes from one cell type, and in addition, transfers lipids between membranes from different cell types. Glycolipid transport is highly efficient, independent of cofactors, solely driven by the chemical potential of GM1 and not discriminating between the extra- and intracellular membrane leaflet. We conclude that GLTP mediated non-vesicular lipid trafficking between native membranes is driven by simple thermodynamic principles and that for intracellular transport less than 1 µM GLTP would be required in the cytosol. Furthermore, the data demonstrates the suitability of GLTP as a tool for artificially increasing glycolipid levels in cellular membranes.

  20. Vibrio tapetis isolated from vesicular skin lesions in Dover sole Solea solea.

    Science.gov (United States)

    Declercq, A M; Chiers, K; Soetaert, M; Lasa, A; Romalde, J L; Polet, H; Haesebrouck, F; Decostere, A

    2015-06-29

    Vibrio tapetis is primarily known as the causative agent for brown ring disease in bivalves, although it has been isolated from cultivated fish during mortalities on farms. Here we describe the first isolation of V. tapetis from wild-caught and subsequently captive-held Dover sole Solea solea. Pathological features consisted of multifocal circular greyish-white skin discolourations evolving into vesicular lesions and subsequent ulcerations on the pigmented side. On the non-pigmented side, multiple circular lesions-white at the center and red at the edges-were evident. Histological examination of the vesicular lesions revealed dermal fluid-filled spaces, collagen tissue necrosis and a mixed inflammatory infiltrate, with large numbers of small rod-shaped bacteria. In the deep skin lesions, loss of scales and dermal connective tissue, with degeneration and fragmentation of the myofibres bordering the ulceration, were noted. Serotyping, DNA-DNA hybridization and REP- and ERIC-PCR techniques showed that the retrieved isolates displayed a profile similar to the representative strain of genotype/serotype O2 which originally was isolated from carpet-shell clam Venerupis decussata and to which isolates obtained from wedge sole Dicologoglossa cuneata were also closely related.

  1. Orf virus interferes with MHC class I surface expression by targeting vesicular transport and Golgi

    Directory of Open Access Journals (Sweden)

    Rohde Jörg

    2012-07-01

    Full Text Available Abstract Background The Orf virus (ORFV, a zoonotic Parapoxvirus, causes pustular skin lesions in small ruminants (goat and sheep. Intriguingly, ORFV can repeatedly infect its host, despite the induction of a specific immunity. These immune modulating and immune evading properties are still unexplained. Results Here, we describe that ORFV infection of permissive cells impairs the intracellular transport of MHC class I molecules (MHC I as a result of structural disruption and fragmentation of the Golgi apparatus. Depending on the duration of infection, we observed a pronounced co-localization of MHC I and COP-I vesicular structures as well as a reduction of MHC I surface expression of up to 50%. These subversion processes are associated with early ORFV gene expression and are accompanied by disturbed carbohydrate trimming of post-ER MHC I. The MHC I population remaining on the cell surface shows an extended half-life, an effect that might be partially controlled also by late ORFV genes. Conclusions The presented data demonstrate that ORFV down-regulates MHC I surface expression in infected cells by targeting the late vesicular export machinery and the structure and function of the Golgi apparatus, which might aid to escape cellular immune recognition.

  2. Dysfunctional TCA-Cycle Metabolism in Glutamate Dehydrogenase Deficient Astrocytes.

    Science.gov (United States)

    Nissen, Jakob D; Pajęcka, Kamilla; Stridh, Malin H; Skytt, Dorte M; Waagepetersen, Helle S

    2015-12-01

    Astrocytes take up glutamate in the synaptic area subsequent to glutamatergic transmission by the aid of high affinity glutamate transporters. Glutamate is converted to glutamine or metabolized to support intermediary metabolism and energy production. Glutamate dehydrogenase (GDH) and aspartate aminotransferase (AAT) catalyze the reversible reaction between glutamate and α-ketoglutarate, which is the initial step for glutamate to enter TCA cycle metabolism. In contrast to GDH, AAT requires a concomitant interconversion of oxaloacetate and aspartate. We have investigated the role of GDH in astrocyte glutamate and glucose metabolism employing siRNA mediated knock down (KD) of GDH in cultured astrocytes using stable and radioactive isotopes for metabolic mapping. An increased level of aspartate was observed upon exposure to [U-(13) C]glutamate in astrocytes exhibiting reduced GDH activity. (13) C Labeling of aspartate and TCA cycle intermediates confirmed that the increased amount of aspartate is associated with elevated TCA cycle flux from α-ketoglutarate to oxaloacetate, i.e. truncated TCA cycle. (13) C Glucose metabolism was elevated in GDH deficient astrocytes as observed by increased de novo synthesis of aspartate via pyruvate carboxylation. In the absence of glucose, lactate production from glutamate via malic enzyme was lower in GDH deficient astrocytes. In conclusions, our studies reveal that metabolism via GDH serves an important anaplerotic role by adding net carbon to the TCA cycle. A reduction in GDH activity seems to cause the astrocytes to up-regulate activity in pathways involved in maintaining the amount of TCA cycle intermediates such as pyruvate carboxylation as well as utilization of alternate substrates such as branched chain amino acids. © 2015 Wiley Periodicals, Inc.

  3. Fístula colecistoduodenal, complicación infrecuente de litiasis vesicular: nuestra experiencia en su manejo quirúrgico

    OpenAIRE

    F. Aguilar-Espinosa; R. Maza-Sánchez; F. Vargas-Solís; G.A. Guerrero-Martínez; J.L. Medina-Reyes; P.I. Flores-Quiroz

    2017-01-01

    Introducción: Las fístulas bilioentéricas son la comunicación anormal entre el sistema biliar y el tracto gastrointestinal, que ocurre de manera espontánea y en la mayoría de los casos es una complicación rara de la litiasis vesicular no tratada. Pueden provocar consecuencias clínicas diversas que, en algunas situaciones, ponen en peligro la vida del paciente. Objetivo: Identificar la incidencia de fístula bilioentérica en pacientes con litiasis vesicular, su presentación clínica, diagnóst...

  4. Didelphis marsupialis como un reservorio potencial u hospedero amplificador del virus de la estomatitis vesicular, serotipo new jersey en Antioquia

    OpenAIRE

    John Arboleda; Carlos Trujillo

    2004-01-01

    La Estomatitis Vesicular (EV) es una enfermedad viral, aguda
    y autolimitante que afecta principalmente bovinos, equinos y
    porcinos. Es producida por el virus de estomatitis vesicular (VEV), serotipos New Jersey (VEV-NJ) e Indiana (VEV-IN), que son los as importantes epidemiológicamente (1). Los estudios serológicos demuestran que VEV-NJ y VEV-IN infectan en forma natural una gran variedad de animales silvestres, que están posiblemente implicados en la  coepizoot...

  5. Targeting glutamate signalling in depression: progress and prospects.

    Science.gov (United States)

    Murrough, James W; Abdallah, Chadi G; Mathew, Sanjay J

    2017-07-01

    Major depressive disorder (MDD) is severely disabling, and current treatments have limited efficacy. The glutamate N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine was recently repurposed as a rapidly acting antidepressant, catalysing the vigorous investigation of glutamate-signalling modulators as novel therapeutic agents for depressive disorders. In this Review, we discuss the progress made in the development of such modulators for the treatment of depression, and examine recent preclinical and translational studies that have investigated the mechanisms of action of glutamate-targeting antidepressants. Fundamental questions remain regarding the future prospects of this line of drug development, including questions concerning safety and tolerability, efficacy, dose-response relationships and therapeutic mechanisms.

  6. Clearance of glutamate inside the synapse and beyond.

    Science.gov (United States)

    Bergles, D E; Diamond, J S; Jahr, C E

    1999-06-01

    The heated debate over the level of postsynaptic receptor occupancy by transmitter has not been extinguished - indeed, new evidence is fanning the flames. Recent experiments using two-photon microscopy suggest that the concentration of glutamate in the synaptic cleft does not attain levels previously suggested. In contrast, recordings from glial cells and studies of extrasynaptic receptor activation indicate that significant quantities of glutamate escape from the cleft following exocytosis. Determining the amount of glutamate efflux from the synaptic cleft and the distance it diffuses is critical to issues of synaptic specificity and the induction of synaptic plasticity.

  7. Fabrication of Implantable, Enzyme-Immobilized Glutamate Sensors for the Monitoring of Glutamate Concentration Changes in Vitro and in Vivo

    Directory of Open Access Journals (Sweden)

    Tina T.-C. Tseng

    2014-06-01

    Full Text Available Glutamate sensors based on the immobilization of glutamate oxidase (GlutOx were prepared by adsorption on electrodeposited chitosan (Method 1 and by crosslinking with glutaraldehyde (Method 2 on micromachined platinum microelectrodes. It was observed that glutamate sensors prepared by Method 1 have faster response time (<2 s and lower detection limit (2.5 ± 1.1 μM compared to that prepared by Method 2 (response time: <5 sec and detection limit: 6.5 ± 1.7 μM; glutamate sensors prepared by Method 2 have a larger linear detection range (20–352 μM and higher sensitivity (86.8 ± 8.8 nA·μM−1·cm−2, N = 12 compared to those prepared by Method 1 (linear detection range: 20–217 μM and sensitivity: 34.9 ± 4.8 nA·μM−1·cm−2, N = 8. The applicability of the glutamate sensors in vivo was also demonstrated. The glutamate sensors were implanted into the rat brain to monitor the stress-induced extracellular glutamate release in the hypothalamus of the awake, freely moving rat.

  8. The Influence of Glutamate on Axonal Compound Action Potential In Vitro.

    Science.gov (United States)

    Abouelela, Ahmed; Wieraszko, Andrzej

    2016-01-01

    Background  Our previous experiments demonstrated modulation of the amplitude of the axonal compound action potential (CAP) by electrical stimulation. To verify assumption that glutamate released from axons could be involved in this phenomenon, the modification of the axonal CAP induced by glutamate was investigated. Objectives  The major objective of this research is to verify the hypothesis that axonal activity would trigger the release of glutamate, which in turn would interact with specific axonal receptors modifying the amplitude of the action potential. Methods  Segments of the sciatic nerve were exposed to exogenous glutamate in vitro, and CAP was recorded before and after glutamate application. In some experiments, the release of radioactive glutamate analog from the sciatic nerve exposed to exogenous glutamate was also evaluated. Results  The glutamate-induced increase in CAP was blocked by different glutamate receptor antagonists. The effect of glutamate was not observed in Ca-free medium, and was blocked by antagonists of calcium channels. Exogenous glutamate, applied to the segments of sciatic nerve, induced the release of radioactive glutamate analog, demonstrating glutamate-induced glutamate release. Immunohistochemical examination revealed that axolemma contains components necessary for glutamatergic neurotransmission. Conclusion  The proteins of the axonal membrane can under the influence of electrical stimulation or exogenous glutamate change membrane permeability and ionic conductance, leading to a change in the amplitude of CAP. We suggest that increased axonal activity leads to the release of glutamate that results in changes in the amplitude of CAPs.

  9. Inhibition of the Mitochondrial Glutamate Carrier SLC25A22 in Astrocytes Leads to Intracellular Glutamate Accumulation

    Directory of Open Access Journals (Sweden)

    Emmanuelle Goubert

    2017-05-01

    Full Text Available The solute carrier family 25 (SLC25 drives the import of a large diversity of metabolites into mitochondria, a key cellular structure involved in many metabolic functions. Mutations of the mitochondrial glutamate carrier SLC25A22 (also named GC1 have been identified in early epileptic encephalopathy (EEE and migrating partial seizures in infancy (MPSI but the pathophysiological mechanism of GC1 deficiency is still unknown, hampered by the absence of an in vivo model. This carrier is mainly expressed in astrocytes and is the principal gate for glutamate entry into mitochondria. A sufficient supply of energy is essential for the proper function of the brain and mitochondria have a pivotal role in maintaining energy homeostasis. In this work, we wanted to study the consequences of GC1 absence in an in vitro model in order to understand if glutamate catabolism and/or mitochondrial function could be affected. First, short hairpin RNA (shRNA designed to specifically silence GC1 were validated in rat C6 glioma cells. Silencing GC1 in C6 resulted in a reduction of the GC1 mRNA combined with a decrease of the mitochondrial glutamate carrier activity. Then, primary astrocyte cultures were prepared and transfected with shRNA-GC1 or mismatch-RNA (mmRNA constructs using the Neon® Transfection System in order to target a high number of primary astrocytes, more than 64%. Silencing GC1 in primary astrocytes resulted in a reduced nicotinamide adenine dinucleotide (Phosphate (NAD(PH formation upon glutamate stimulation. We also observed that the mitochondrial respiratory chain (MRC was functional after glucose stimulation but not activated by glutamate, resulting in a lower level of cellular adenosine triphosphate (ATP in silenced astrocytes compared to control cells. Moreover, GC1 inactivation resulted in an intracellular glutamate accumulation. Our results show that mitochondrial glutamate transport via GC1 is important in sustaining glutamate homeostasis in

  10. Dopamine D1-D2 receptor heteromer in dual phenotype GABA/glutamate-coexpressing striatal medium spiny neurons: regulation of BDNF, GAD67 and VGLUT1/2.

    Directory of Open Access Journals (Sweden)

    Melissa L Perreault

    Full Text Available In basal ganglia a significant subset of GABAergic medium spiny neurons (MSNs coexpress D1 and D2 receptors (D1R and D2R along with the neuropeptides dynorphin (DYN and enkephalin (ENK. These coexpressing neurons have been recently shown to have a region-specific distribution throughout the mesolimbic and basal ganglia circuits. While the functional relevance of these MSNs remains relatively unexplored, they have been shown to exhibit the unique property of expressing the dopamine D1-D2 receptor heteromer, a novel receptor complex with distinct pharmacology and cell signaling properties. Here we showed that MSNs coexpressing the D1R and D2R also exhibited a dual GABA/glutamate phenotype. Activation of the D1R-D2R heteromer in these neurons resulted in the simultaneous, but differential regulation of proteins involved in GABA and glutamate production or vesicular uptake in the nucleus accumbens (NAc, ventral tegmental area (VTA, caudate putamen and substantia nigra (SN. Additionally, activation of the D1R-D2R heteromer in NAc shell, but not NAc core, differentially altered protein expression in VTA and SN, regions rich in dopamine cell bodies. The identification of a MSN with dual inhibitory and excitatory intrinsic functions provides new insights into the neuroanatomy of the basal ganglia and demonstrates a novel source of glutamate in this circuit. Furthermore, the demonstration of a dopamine receptor complex with the potential to differentially regulate the expression of proteins directly involved in GABAergic inhibitory or glutamatergic excitatory activation in VTA and SN may potentially provide new insights into the regulation of dopamine neuron activity. This could have broad implications in understanding how dysregulation of neurotransmission within basal ganglia contributes to dopamine neuronal dysfunction.

  11. Glutamate neurotransmission is affected in prenatally stressed offspring

    DEFF Research Database (Denmark)

    Adrover, Ezequiela; Pallarés, Maria Eugenia; Baier, Carlos Javier

    2015-01-01

    with synaptic loss. Since metabolism of glutamate is dependent on interactions between neurons and surrounding astroglia, our results suggest that glutamate neurotransmitter pathways might be impaired in the brain of prenatally stressed rats. To study the effect of prenatal stress on the metabolism...... uptake capacity for glutamate in the FCx of PS male offspring while no such changes were observed in the HPC. The results show that changes mediated by PS on the adult glutamatergic system are brain region specific. Overall, PS produces long-term changes in the glutamatergic system modulating......Previous studies from our laboratory have shown that male adult offspring of stressed mothers exhibited higher levels of ionotropic and metabotropic glutamate receptors than control rats. These offspring also showed long-lasting astroglial hypertrophy and a reduced dendritic arborization...

  12. Modeling of glutamic acid production by Lactobacillus plantarum MNZ

    National Research Council Canada - National Science Library

    Zareian, Mohsen; Ebrahimpour, Afshin; Mohamed, Abdul Karim Sabo; Saari, Nazamid

    2014-01-01

    ...-amino butyric acid (GABA). In the present study, culture condition for enhanced glutamic acid production by Lactobacillus plantarum MNZ was optimized and the influence of such conditions on GABA production was evaluated. Results...

  13. Receptors of glutamate and neurotrophin in vestibular neuronal functions.

    Science.gov (United States)

    Chan, Y S; Chen, L W; Lai, C H; Shum, D K Y; Yung, K K L; Zhang, F X

    2003-01-01

    The last decade has witnessed advances in understanding the roles of receptors of neurotrophin and glutamate in the vestibular system. In the first section of this review, the biological actions of neurotrophins and their receptors in the peripheral and central vestibular systems are summarized. Emphasis will be placed on the roles of neurotrophins in developmental plasticity and in the maintenance of vestibular function in the adult animal. This is reviewed in relation to the developmental expression pattern of neurotrophins and their receptors within the vestibular nuclei. The second part is focused on the functional role of different glutamate receptors on central vestibular neurons. The developmental expression pattern of glutamate receptor subunits within the vestibular nuclei is reviewed in relation to the potential role of glutamate receptors in regulating the development of vestibular function. Copyright 2003 National Science Council, ROC and S. Karger AG, Basel

  14. Bidirectional Control of Synaptic GABAAR Clustering by Glutamate and Calcium

    Directory of Open Access Journals (Sweden)

    Hiroko Bannai

    2015-12-01

    Full Text Available GABAergic synaptic transmission regulates brain function by establishing the appropriate excitation-inhibition (E/I balance in neural circuits. The structure and function of GABAergic synapses are sensitive to destabilization by impinging neurotransmitters. However, signaling mechanisms that promote the restorative homeostatic stabilization of GABAergic synapses remain unknown. Here, by quantum dot single-particle tracking, we characterize a signaling pathway that promotes the stability of GABAA receptor (GABAAR postsynaptic organization. Slow metabotropic glutamate receptor signaling activates IP3 receptor-dependent calcium release and protein kinase C to promote GABAAR clustering and GABAergic transmission. This GABAAR stabilization pathway counteracts the rapid cluster dispersion caused by glutamate-driven NMDA receptor-dependent calcium influx and calcineurin dephosphorylation, including in conditions of pathological glutamate toxicity. These findings show that glutamate activates distinct receptors and spatiotemporal patterns of calcium signaling for opposing control of GABAergic synapses.

  15. Update on food safety of monosodium l-glutamate (MSG).

    Science.gov (United States)

    Henry-Unaeze, Helen Nonye

    2017-12-01

    This evidence-based safety review of the flavor enhancer monosodium l-glutamate (MSG) was triggered by its global use and recent studies expressing some safety concerns. This article obtained information through search of evidence-based scientific databases, especially the US National Library of Medicine NIH. (A) MSG is a water-soluble salt of glutamate, a non-essential amino acid, normally synthesized in the body and prevalent in protein foods. (B) MSG is utilized world-wide for its "umami" taste and flavor enhancement qualities, (C) the human body does not discriminate between glutamate present in food and that added as seasoning, (D) glutamate metabolism is compartmentalized in the human body without reported ethnic differences, (E) glutamate does not passively cross biological membranes, (F) food glutamate is completely metabolized by gut cells as energy source and serves as key substrate for other important metabolites in the liver, (G) normal food use of MSG is dose-dependent and self-limiting without elevation in plasma glutamate, (H) the recent EFSA acceptable daily intake (30mg/kg body weight/day) is not attainable when MSG is consumed at normal dietary level, (I) scientists have not been able to consistently elicit reactions in double-blind studies with 'sensitive' individuals using MSG or placebo in food. Based on the above observations (A-I), high quality MSG is safe for all life-cycle stages without respect to ethnic origin or culinary background. MSG researchers are advised to employ appropriate scientific methodologies, consider glutamate metabolism and its normal food use before extrapolating pharmacological rodent studies to humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Glutamic Acid Selective Chemical Cleavage of Peptide Bonds.

    Science.gov (United States)

    Nalbone, Joseph M; Lahankar, Neelam; Buissereth, Lyssa; Raj, Monika

    2016-03-04

    Site-specific hydrolysis of peptide bonds at glutamic acid under neutral aqueous conditions is reported. The method relies on the activation of the backbone amide chain at glutamic acid by the formation of a pyroglutamyl (pGlu) imide moiety. This activation increases the susceptibility of a peptide bond toward hydrolysis. The method is highly specific and demonstrates broad substrate scope including cleavage of various bioactive peptides with unnatural amino acid residues, which are unsuitable substrates for enzymatic hydrolysis.

  17. Monosodium glutamate is not likely to be genotoxic.

    Science.gov (United States)

    Rogers, Michael D

    2016-08-01

    The International Glutamate Technical Committee (IGTC) wishes to comment on a recent publication in the Journal entitled "Genotoxicity of monosodium glutamate" (authored by Ataseven N, Yüzbaşıoğlu D, Keskin AÇ and Ünal F) (Ataseven et al. 2016). In particular, we wish to highlight that, in our considered view, the results of this study were inappropriately discussed and that references were selectively used. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Amiodarone reduces depolarization-evoked glutamate release from hippocampual synaptosomes.

    Science.gov (United States)

    Chang, Chia Yu; Hung, Chi Feng; Huang, Shu Kuei; Kuo, Jinn Rung; Wang, Su Jane

    2017-03-01

    Decreased brain glutamate level has emerged as a new therapeutic approach for epilepsy. This study investigated the effect and mechanism of amiodarone, an anti-arrhythmic drug with antiepileptic activity, on glutamate release in the rat hippocampus. In a synaptosomal preparation, amiodarone reduced 4-aminopyridine-evoked Ca2+-dependent glutamate release and cytosolic Ca2+ concentration elevation. Amiodarone did not affect the 4-aminopyridine-evoked depolarization of the synaptosomal membrane potential or the Na+ channel activator veratridine-evoked glutamate release, indicating that the amiodarone-mediated inhibition of glutamate release is not caused by a decrease in synaptosomal excitability. The inhibitory effect of amiodarone on 4-aminopyridine-evoked glutamate release was markedly decreased in synaptosomes pretreated with the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channel blocker ω-conotoxin MVIIC, the calmodulin antagonists W7 and calmidazolium, or the protein kinase A inhibitors H89 and KT5720. However, the intracellular Ca2+-release inhibitors dantrolene and CGP37157 had no effect on the amiodarone-mediated inhibition of glutamate release. Furthermore, amiodarone reduced the frequency of miniature excitatory postsynaptic currents without affecting their amplitude in hippocampal slices. Our data suggest that amiodarone reduces Ca2+ influx through N- and P/Q-type Ca2+ channels, subsequently reducing the Ca2+-calmodulin/protein kinase A cascade to inhibit the evoked glutamate release from rat hippocampal nerve terminals. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  19. A Glio-Protective Role of mir-263a by Tuning Sensitivity to Glutamate

    DEFF Research Database (Denmark)

    Aw, Sherry Shiying; Lim, Isaac Kok Hwee; Tang, Melissa Xue Mei

    2017-01-01

    Glutamate is a ubiquitous neurotransmitter, mediating information flow between neurons. Defects in the regulation of glutamatergic transmission can result in glutamate toxicity, which is associated with neurodegeneration. Interestingly, glutamate receptors are expressed in glia, but little is kno...... of glutamate receptor levels protects glia from excitotoxicity, ensuring CNS health. Chronic low-level glutamate receptor overexpression due to mutations affecting microRNA (miRNA) regulation might contribute to glial dysfunction and CNS impairment....

  20. Extrasynaptic vesicular transmitter release from the somata of substantia nigra neurons in rat midbrain slices.

    Science.gov (United States)

    Jaffe, E H; Marty, A; Schulte, A; Chow, R H

    1998-05-15

    Substantia nigra neurons release dopamine from their somatodendritic regions. A long-unresolved question is whether this release occurs by exocytosis or by a nonvesicular mechanism. We used carbon fiber microelectrodes in a brainstem slice to assay secretion from single cell bodies that had been cleared of connective tissue. Amperometry at the carbon fiber microelectrodes revealed unitary events in approximately 90% of cells in resting conditions. These events had charge integrals ranging from a few femtocoulombs to several hundred femtocoulombs (fC). Local glutamate application enhanced the event frequency by 3.5-fold on average and up to 10-fold in highly responsive cells, although the mean charge integral was not modified. Local application of a high K+-containing saline had effects similar to those of glutamate. The frequency of resting and stimulated amperometric events was much lower at 21-22 degreesC than at 32-35 degreesC. The addition of Cd2+ (50 microM), a blocker of voltage-dependent Ca2+ channels, to the bath solution blocked the stimulatory effects of glutamate. These results suggest that dopamine is released from the somata of substantia nigra neurons by exocytosis and that this mechanism is regulated by neuronal electrical activity. More generally, this study demonstrates the applicability of carbon fiber microelectrodes to the measurement of quantal monoamine secretion in brain slices.

  1. Glutamate Receptor Ion Channels: Structure, Regulation, and Function

    Science.gov (United States)

    Wollmuth, Lonnie P.; McBain, Chris J.; Menniti, Frank S.; Vance, Katie M.; Ogden, Kevin K.; Hansen, Kasper B.; Yuan, Hongjie; Myers, Scott J.; Dingledine, Ray

    2010-01-01

    The mammalian ionotropic glutamate receptor family encodes 18 gene products that coassemble to form ligand-gated ion channels containing an agonist recognition site, a transmembrane ion permeation pathway, and gating elements that couple agonist-induced conformational changes to the opening or closing of the permeation pore. Glutamate receptors mediate fast excitatory synaptic transmission in the central nervous system and are localized on neuronal and non-neuronal cells. These receptors regulate a broad spectrum of processes in the brain, spinal cord, retina, and peripheral nervous system. Glutamate receptors are postulated to play important roles in numerous neurological diseases and have attracted intense scrutiny. The description of glutamate receptor structure, including its transmembrane elements, reveals a complex assembly of multiple semiautonomous extracellular domains linked to a pore-forming element with striking resemblance to an inverted potassium channel. In this review we discuss International Union of Basic and Clinical Pharmacology glutamate receptor nomenclature, structure, assembly, accessory subunits, interacting proteins, gene expression and translation, post-translational modifications, agonist and antagonist pharmacology, allosteric modulation, mechanisms of gating and permeation, roles in normal physiological function, as well as the potential therapeutic use of pharmacological agents acting at glutamate receptors. PMID:20716669

  2. In vitro evidence for the brain glutamate efflux hypothesis

    DEFF Research Database (Denmark)

    Helms, Hans Christian; Madelung, Rasmus; Waagepetersen, Helle Sønderby

    2012-01-01

    The concentration of the excitotoxic amino acid, L-glutamate, in brain interstitial fluid is tightly regulated by uptake transporters and metabolism in astrocytes and neurons. The aim of this study was to investigate the possible role of the blood-brain barrier endothelium in brain L-glutamate ho......The concentration of the excitotoxic amino acid, L-glutamate, in brain interstitial fluid is tightly regulated by uptake transporters and metabolism in astrocytes and neurons. The aim of this study was to investigate the possible role of the blood-brain barrier endothelium in brain L......-glutamate homeostasis. Transendothelial transport- and accumulation studies of (3) H-L-glutamate, (3) H-L-aspartate, and (3) H-D-aspartate in an electrically tight bovine endothelial/rat astrocyte blood-brain barrier coculture model were performed. After 6 days in culture, the endothelium displayed transendothelial...... was shown with immunofluorescence. Overall, the findings suggest that the blood-brain barrier itself may participate in regulating brain L-glutamate concentrations. © 2012 Wiley Periodicals, Inc....

  3. Carbon fiber ultramicrodic electrode electrodeposited with over-oxidized polypyrrole for amperometric detection of vesicular exocytosis from pheochromocytoma cell.

    Science.gov (United States)

    Wang, Li; Xu, Huiren; Song, Yilin; Luo, Jinping; Xu, Shengwei; Zhang, Song; Liu, Juntao; Cai, Xinxia

    2015-01-06

    Vesicular exocytosis is ubiquitous, but it is difficult to detect within the cells' communication mechanism. For this purpose, a 2 µm ultramicrodic carbon fiber electrode was fabricated in this work based on electrodeposition with over-oxidized polypyrrole nanoparticle (PPyox-CFE), which was applied successfully for real-time monitoring of quantal exocytosis from individual pheochromocytoma (PC12) cells. PPyox-CFE was evaluated by dopamine (DA) solutions through cyclic voltammetry and amperometry electrochemical methods, and results revealed that PPyox-CFE improved the detection limit of DA. In particular, the sensitivity of DA was improved to 24.55 µA·µM(-1)·µm(-2) using the PPyox-CFE. The ultramicrodic electrode combined with the patch-clamp system was used to detect vesicular exocytosis of DA from individual PC12 cells with 60 mM K+ stimulation. A total of 287 spikes released from 7 PC12 cells were statistically analyzed. The current amplitude (Imax) and the released charge (Q) of the amperometric spikes from the DA release by a stimulated PC12 cell is 45.1 ± 12.5 pA and 0.18 ± 0.04 pC, respectively. Furthermore, on average ~562,000 molecules were released in each vesicular exocytosis. PPyox-CFE, with its capability of detecting vesicular exocytosis, has potential application in neuron communication research.

  4. Oncolytic recombinant vesicular stomatitis virus (VSV) is nonpathogenic and non-transmissible in pigs, a natural host of VSV

    Science.gov (United States)

    Vesicular stomatitis virus (VSV) is a negative stranded RNA virus that naturally causes disease in agricultural livestock including horses, cattle and pigs. The two main identified VSV strains are the New Jersey (VSNJV) and Indiana (VSIV) strains. VSV is a rapidly replicating, potently immunogenic v...

  5. Carbon Fiber Ultramicrodic Electrode Electrodeposited with Over-Oxidized Polypyrrole for Amperometric Detection of Vesicular Exocytosis from Pheochromocytoma Cell

    Directory of Open Access Journals (Sweden)

    Li Wang

    2015-01-01

    Full Text Available Vesicular exocytosis is ubiquitous, but it is difficult to detect within the cells’ communication mechanism. For this purpose, a 2 µm ultramicrodic carbon fiber electrode was fabricated in this work based on electrodeposition with over-oxidized polypyrrole nanoparticle (PPyox-CFE, which was applied successfully for real-time monitoring of quantal exocytosis from individual pheochromocytoma (PC12 cells. PPyox-CFE was evaluated by dopamine (DA solutions through cyclic voltammetry and amperometry electrochemical methods, and results revealed that PPyox-CFE improved the detection limit of DA. In particular, the sensitivity of DA was improved to 24.55 µA·µM−1·µm−2 using the PPyox-CFE. The ultramicrodic electrode combined with the patch-clamp system was used to detect vesicular exocytosis of DA from individual PC12 cells with 60 mM K+ stimulation. A total of 287 spikes released from 7 PC12 cells were statistically analyzed. The current amplitude (Imax and the released charge (Q of the amperometric spikes from the DA release by a stimulated PC12 cell is 45.1 ± 12.5 pA and 0.18 ± 0.04 pC, respectively. Furthermore, on average ~562,000 molecules were released in each vesicular exocytosis. PPyox-CFE, with its capability of detecting vesicular exocytosis, has potential application in neuron communication research.

  6. Contribution of vesicular and cytosolic dopamine to the increased striatal dopamine efflux elicited by intrastriatal injection of dexamphetamine.

    NARCIS (Netherlands)

    Watanabe, S.; Aono, Y.; Fusa, K.; Takada, K.; Saigusa, T.; Koshikawa, N.; Cools, A.R.

    2005-01-01

    Systemic administration of high doses of dexamphetamine induces a dopamine efflux that has its intracellular origin in both the vesicular, reserpine-sensitive dopamine pool and the cytosolic, alpha-methyl-para-tyrosine-sensitive, newly synthesized dopamine pool. It remains unknown whether locally

  7. Contribution of vesicular and cytosolic dopamine to the increased striatal dopamine efflux elicited by intrastriatal injection of SKF38393.

    NARCIS (Netherlands)

    Saigusa, T.; Aono, Y.; Sekino, R.; Uchida, T.; Takada, K.; Oi, Y.; Koshikawa, N.; Cools, A.R.

    2009-01-01

    Like dexamphetamine, SKF38393 induces an increase in striatal dopamine efflux which is insensitive for tetrodotoxin, Ca(2+) independent and prevented by a dopamine transporter inhibitor. The dexamphetamine-induced striatal dopamine efflux originates from both the reserpine-sensitive vesicular

  8. Reduction of bacterial growth by a vesicular-arbuscular mycorrhizal fungus in the rhizosphere of cucumber (Cucumis sativus L.)

    DEFF Research Database (Denmark)

    Christensen, H.; Jakobsen, I.

    1993-01-01

    Cucumber was grown in a partially sterilized sand-soil mixture with the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus fasciculatum or left uninoculated. Fresh soil extract was places in polyvinyl chloride tubes without propagules of mycorrhizal fungi. Root tips and root segments...

  9. Carbon Fiber Ultramicrodic Electrode Electrodeposited with Over-Oxidized Polypyrrole for Amperometric Detection of Vesicular Exocytosis from Pheochromocytoma Cell

    Science.gov (United States)

    Wang, Li; Xu, Huiren; Song, Yilin; Luo, Jinping; Xu, Shengwei; Zhang, Song; Liu, Juntao; Cai, Xinxia

    2015-01-01

    Vesicular exocytosis is ubiquitous, but it is difficult to detect within the cells' communication mechanism. For this purpose, a 2 μm ultramicrodic carbon fiber electrode was fabricated in this work based on electrodeposition with over-oxidized polypyrrole nanoparticle (PPyox-CFE), which was applied successfully for real-time monitoring of quantal exocytosis from individual pheochromocytoma (PC12) cells. PPyox-CFE was evaluated by dopamine (DA) solutions through cyclic voltammetry and amperometry electrochemical methods, and results revealed that PPyox-CFE improved the detection limit of DA. In particular, the sensitivity of DA was improved to 24.55 μA·μM−1·μm−2 using the PPyox-CFE. The ultramicrodic electrode combined with the patch-clamp system was used to detect vesicular exocytosis of DA from individual PC12 cells with 60 mM K+ stimulation. A total of 287 spikes released from 7 PC12 cells were statistically analyzed. The current amplitude (Imax) and the released charge (Q) of the amperometric spikes from the DA release by a stimulated PC12 cell is 45.1 ± 12.5 pA and 0.18 ± 0.04 pC, respectively. Furthermore, on average ∼562,000 molecules were released in each vesicular exocytosis. PPyox-CFE, with its capability of detecting vesicular exocytosis, has potential application in neuron communication research. PMID:25569759

  10. APPARENT LACK OF VESICULAR-ARBUSCULAR MYCORRHIZA (VAM) IN SEAGRASSES ZOSTERA MARINA L. AND THALASSIA TESTUDIUM BANKS EX KONIG

    Science.gov (United States)

    We examined two populations of Zostera marina L. and one of Thalassia testudinum Banks ex Konig for presence of vesicular-arbuscular mycorrhiza (VAM). None of these plants showed any VAM colonization. In addition, we were unable to find any literature references on the presence o...

  11. [Glutamic acid as a universal extracellular signal].

    Science.gov (United States)

    Yoneda, Yukio

    2015-08-01

    The prevailing view is that both glutamic (Glu) and gamma-aminobutyric (GABA) acids play a role as an amino acid neurotransmitter released from neurons. However, little attention has been paid to the possible expression and functionality of signaling machineries required for amino acidergic neurotransmission in cells other than central neurons. In line with our first demonstration of the presence of Glu receptors outside the brain, in this review I will outline our recent findings accumulated since then on the physiological and pathological significance of neuronal amino acids as an extracellular signal essential for homeostasis in a variety of phenotypic cells. In undifferentiated neural progenitor cells, for instance, functional expression is seen with different signaling machineries used for glutamatergic and GABAergic neurotransmission in neurons. Moreover, Glu plays a role in mechanisms underlying suppression of proliferation for self-replication in undifferentiated mesenchymal stem cells. There is more accumulating evidence for neuronal amino acids playing a role as an extracellular autocrine or paracrine signal commonly used in different phenotypic cells. Evaluation of drugs currently used could be thus beneficial for the efficient prophylaxis and/or the therapy of a variety of diseases relevant to disturbance of amino acid signaling in diverse organs.

  12. Vesicular monoamine transporter 1 gene polymorphism and white matter integrity in major depressive disorder.

    Science.gov (United States)

    Won, Eunsoo; Han, Kyu-Man; Kang, June; Kim, Aram; Yoon, Ho-Kyoung; Chang, Hun Soo; Park, Ji-Young; Lee, Min-Soo; Greenberg, Tsafrir; Tae, Woo-Suk; Ham, Byung-Joo

    2017-07-03

    The genetic variant of the vesicular monoamine transporter 1 gene (VMAT1) has been suggested to be associated with monoaminergic signaling and neural circuit activity related to emotion processing. We aimed to investigate microstructural changes in white matter tracts of patients with major depressive disorder (MDD), and examined the interaction effect between VMAT1 Thr136Ile (rs1390938) polymorphism and MDD on white matter integrity. Diffusion tensor imaging (DTI) and VMAT1 Thr136Ile (rs1390938) genotyping were performed on 103 patients diagnosed with MDD and 83 healthy control participants. DTI was used to investigate microstructural changes in white matter tracts in patients compared to healthy controls. The possible interaction effect between rs1390938 and MDD on white matter integrity was also assessed. Patients with MDD exhibited lower fractional anisotropy (FA) values of the forceps major (pdepression. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Polysaccharide nano-vesicular multidrug carriers for synergistic killing of cancer cells

    Science.gov (United States)

    Pramod, P. S.; Shah, Ruchira; Chaphekar, Sonali; Balasubramanian, Nagaraj; Jayakannan, Manickam

    2014-09-01

    Multi-drug delivery based on polymer nano-scaffolds is an essential protocol to be developed for better administration of anticancer drugs to enhance their therapeutic efficacies against cancer cells. Here, we report dual delivery polysaccharide nano-vesicles that are capable of loading and delivering both water soluble and water insoluble drugs together in a single polymer scaffold. The selective rupture of the nano-vesicular assembly under intracellular enzyme conditions allowed the simultaneous delivery of a hydrophobic drug camptothecin (CPT) and hydrophilic drug doxorubicin (DOX) supporting their synergistic killing of breast and colon cancer cells. The polysaccharide nano-vesicles have allowed us to address a few important questions regarding the need for multiple drug administration in cancer cells including (a) the role of simultaneous drug release, (b) antagonistic versus synergistic effects of drug combinations and (c) how these are affected by the ratio of drugs. Further, evaluation of the role of caveolae in endocytosis of these polymer scaffolds was also made. The vesicular scaffolds were found to preserve and deliver DOX resulting in 50-60% better killing of cancer cells than the free drug. Additionally, dual loaded nano-vesicles when compared to drug cocktails with individual drugs in separate nano-vesicles (at comparable molar ratios) suggest the relative drug concentration following release and mode of delivery to be both important in cancer cell killing. Results from these experiments have revealed newly developed polysaccharide nano-vesicles loaded with DOX and CPT drugs as potential candidates for improved breast cancer cell killing. Thus, these custom-designed polysaccharide nano-vesicles provide a new perspective on multi-anticancer drug delivery systems and their efficacy.Multi-drug delivery based on polymer nano-scaffolds is an essential protocol to be developed for better administration of anticancer drugs to enhance their therapeutic

  14. LDL receptor and its family members serve as the cellular receptors for vesicular stomatitis virus

    Science.gov (United States)

    Finkelshtein, Danit; Werman, Ariel; Novick, Daniela; Barak, Sara; Rubinstein, Menachem

    2013-01-01

    Vesicular stomatitis virus (VSV) exhibits a remarkably robust and pantropic infectivity, mediated by its coat protein, VSV-G. Using this property, recombinant forms of VSV and VSV-G-pseudotyped viral vectors are being developed for gene therapy, vaccination, and viral oncolysis and are extensively used for gene transduction in vivo and in vitro. The broad tropism of VSV suggests that it enters cells through a highly ubiquitous receptor, whose identity has so far remained elusive. Here we show that the LDL receptor (LDLR) serves as the major entry port of VSV and of VSV-G-pseudotyped lentiviral vectors in human and mouse cells, whereas other LDLR family members serve as alternative receptors. The widespread expression of LDLR family members accounts for the pantropism of VSV and for the broad applicability of VSV-G-pseudotyped viral vectors for gene transduction. PMID:23589850

  15. Impact of Vesicular Stomatitis Virus M Proteins on Different Cellular Functions.

    Directory of Open Access Journals (Sweden)

    Natalia Redondo

    Full Text Available Three different matrix (M proteins termed M1, M2 and M3 have been described in cells infected with vesicular stomatitis virus (VSV. Individual expression of VSV M proteins induces an evident cytopathic effect including cell rounding and detachment, in addition to a partial inhibition of cellular protein synthesis, likely mediated by an indirect mechanism. Analogous to viroporins, M1 promotes the budding of new virus particles; however, this process does not produce an increase in plasma membrane permeability. In contrast to M1, M2 and M3 neither interact with the cellular membrane nor promote the budding of double membrane vesicles at the cell surface. Nonetheless, all three species of M protein interfere with the transport of cellular mRNAs from the nucleus to the cytoplasm and also modulate the redistribution of the splicing factor. The present findings indicate that all three VSV M proteins share some activities that interfere with host cell functions.

  16. Spectrum of Text Information Content in the RNA Sequence of the Vesicular Stomatitis Virus

    Science.gov (United States)

    Filyukov, Alexander A.

    A new strategy to recognize patterns in the DNA sequences with functional significance is proposed. The strategy is based on the general definition of any individual organism as a Gibbsian ensemble of identical personal DNA molecules. This approach provides application of the methods of statistical thermodynamics of irreversible steady processes to genome informatics. The random processes theory and its Markov chains approximation lead in this approach directly to the definition of the generalized concept of evolution entropy and to the genuine measure of text information content in the sequences. Computer-assisted proofs of the existence of the nonequilibrium steady state conditions in genome molecule were obtained by investigation of the special type balance relations in the vesicular stomatitis virus (VSV) RNA sequence. The main maxima of the text information content were decoded and denominated. The established coding principles are connected with deviations from equilibrium conditions and from equipartition.

  17. Pseudotyping of vesicular stomatitis virus with the envelope glycoproteins of highly pathogenic avian influenza viruses.

    Science.gov (United States)

    Zimmer, Gert; Locher, Samira; Berger Rentsch, Marianne; Halbherr, Stefan J

    2014-08-01

    Pseudotype viruses are useful for studying the envelope proteins of harmful viruses. This work describes the pseudotyping of vesicular stomatitis virus (VSV) with the envelope glycoproteins of highly pathogenic avian influenza viruses. VSV lacking the homotypic glycoprotein (G) gene (VSVΔG) was used to express haemagglutinin (HA), neuraminidase (NA) or the combination of both. Propagation-competent pseudotype viruses were only obtained when HA and NA were expressed from the same vector genome. Pseudotype viruses containing HA from different H5 clades were neutralized specifically by immune sera directed against the corresponding clade. Fast and sensitive reading of test results was achieved by vector-mediated expression of GFP. Pseudotype viruses expressing a mutant VSV matrix protein showed restricted spread in IFN-competent cells. This pseudotype system will facilitate the detection of neutralizing antibodies against virulent influenza viruses, circumventing the need for high-level biosafety containment. © 2014 The Authors.

  18. `Full fusion' is not ineluctable during vesicular exocytosis of neurotransmitters by endocrine cells

    Science.gov (United States)

    Oleinick, Alexander; Svir, Irina; Amatore, Christian

    2017-01-01

    Vesicular exocytosis is an essential and ubiquitous process in neurons and endocrine cells by which neurotransmitters are released in synaptic clefts or extracellular fluids. It involves the fusion of a vesicle loaded with chemical messengers with the cell membrane through a nanometric fusion pore. In endocrine cells, unless it closes after some flickering (`Kiss-and-Run' events), this initial pore is supposed to expand exponentially, leading to a full integration of the vesicle membrane into the cell membrane-a stage called `full fusion'. We report here a compact analytical formulation that allows precise measurements of the fusion pore expansion extent and rate to be extracted from individual amperometric spike time courses. These data definitively establish that, during release of catecholamines, fusion pores enlarge at most to approximately one-fifth of the radius of their parent vesicle, hence ruling out the ineluctability of `full fusion'.

  19. The Dynamic Control of Kiss-And-Run and Vesicular Reuse Probed with Single Nanoparticles

    Science.gov (United States)

    Zhang, Qi; Li, Yulong; Tsien, Richard W.

    2009-01-01

    Summary Vesicular secretion of neurotransmitter is essential for neuronal communication. Kiss-and-run is a mode of membrane fusion and retrieval without the full collapse of the vesicle into the plasma membrane and de novo regeneration. The significance of kiss-and-run during efficient neurotransmission has remained in doubt. We developed an approach for loading individual synaptic vesicles with single quantum dots. Their size and pH-dependent photoluminescence change allowed us to distinguish kiss-and-run from full-collapse fusion and to track single vesicles through multiple rounds of kiss-and-run and reuse, without perturbing vesicle cycling. Kiss-and-run dominated at the beginning of stimulus trains, reflecting the preference of vesicles with high release probability. Its incidence was increased by rapid firing, a response appropriate to meet the dynamic demands of neurotransmission. PMID:19213879

  20. Unusual armadillo fold in the human general vesicular transport factor p115.

    Directory of Open Access Journals (Sweden)

    Harald Striegl

    Full Text Available The golgin family gives identity and structure to the Golgi apparatus and is part of a complex protein network at the Golgi membrane. The golgin p115 is targeted by the GTPase Rab1a, contains a large globular head region and a long region of coiled-coil which forms an extended rod-like structure. p115 serves as vesicle tethering factor and plays an important role at different steps of vesicular transport. Here we present the 2.2 A-resolution X-ray structure of the globular head region of p115. The structure exhibits an armadillo fold that is decorated by elongated loops and carries a C-terminal non-canonical repeat. This terminal repeat folds into the armadillo superhelical groove and allows homodimeric association with important implications for p115 mediated multiple protein interactions and tethering.

  1. Cutting Edge: Innate Immune Augmenting Vesicular Stomatitis Virus Expressing Zika Virus Proteins Confers Protective Immunity.

    Science.gov (United States)

    Betancourt, Dillon; de Queiroz, Nina M G P; Xia, Tianli; Ahn, Jeonghyun; Barber, Glen N

    2017-04-15

    Zika virus (ZIKV) has become a serious public health concern because of its link to brain damage in developing human fetuses. Recombinant vesicular stomatitis virus (rVSV) was shown to be a highly effective and safe vector for the delivery of foreign immunogens for vaccine purposes. In this study, we generated rVSVs (wild-type and attenuated VSV with mutated matrix protein [VSVm] versions) that express either the full length ZIKV envelope protein (ZENV) alone or include the ZENV precursor to the membrane protein upstream of the envelope protein, and our rVSV-ZIKV constructs showed efficient immunogenicity in murine models. We also demonstrated maternal protective immunity in challenged newborn mice born to female mice vaccinated with VSVm-ZENV containing the transmembrane domain. Our data indicate that rVSVm may be a suitable strategy for the design of effective vaccines against ZIKV. Copyright © 2017 by The American Association of Immunologists, Inc.

  2. Pesquisaje de litiasis vesicular en un sector de población supuestamente sana

    OpenAIRE

    Lázaro Yera Abreus; Mercedes Cárdenas Drake; Angel Gutiérrez Rojas

    1997-01-01

    Se hace un estudio de frecuencia de litiasis vesicular en un sector de población supuestamente sana, en el que se encontró una frecuencia de la afección de un 6,2 %, el predominio de las personas de la raza blanca sobre las de la raza negra fue de sólo 1,8:1; la afección es mucho más frecuente en el sexo femenino que en el masculino (proporción de 9:1) y en personas mayores de 40 años (60 %) con sobrepeso u obesas (85 %), y puede cursar de forma totalmente asintomática en el 50 % de los casos...

  3. Enhancing poly-γ-glutamic acid production in Bacillus amyloliquefaciens by introducing the glutamate synthesis features from Corynebacterium glutamicum.

    Science.gov (United States)

    Feng, Jun; Quan, Yufen; Gu, Yanyan; Liu, Fenghong; Huang, Xiaozhong; Shen, Haosheng; Dang, Yulei; Cao, Mingfeng; Gao, Weixia; Lu, Xiaoyun; Wang, Yi; Song, Cunjiang; Wang, Shufang

    2017-05-22

    Poly-γ-glutamic acid (γ-PGA) is a valuable polymer with glutamate as its sole precursor. Enhancement of the intracellular glutamate synthesis is a very important strategy for the improvement of γ-PGA production, especially for those glutamate-independent γ-PGA producing strains. Corynebacterium glutamicum has long been used for industrial glutamate production and it exhibits some unique features for glutamate synthesis; therefore introduction of these metabolic characters into the γ-PGA producing strain might lead to increased intracellular glutamate availability, and thus ultimate γ-PGA production. In this study, the unique glutamate synthesis features from C. glutamicum was introduced into the glutamate-independent γ-PGA producing Bacillus amyloliquefaciens NK-1 strain. After introducing the energy-saving NADPH-dependent glutamate dehydrogenase (NADPH-GDH) pathway, the NK-1 (pHT315-gdh) strain showed slightly increase (by 9.1%) in γ-PGA production. Moreover, an optimized metabolic toggle switch for controlling the expression of ɑ-oxoglutarate dehydrogenase complex (ODHC) was introduced into the NK-1 strain, because it was previously shown that the ODHC in C. glutamicum was completely inhibited when glutamate was actively produced. The obtained NK-PO1 (pHT01-xylR) strain showed 66.2% higher γ-PGA production than the NK-1 strain. However, the further combination of these two strategies (introducing both NADPH-GDH pathway and the metabolic toggle switch) did not lead to further increase of γ-PGA production but rather the resultant γ-PGA production was even lower than that in the NK-1 strain. We proposed new metabolic engineering strategies to improve the γ-PGA production in B. amyloliquefaciens. The NK-1 (pHT315-gdh) strain with the introduction of NADPH-GDH pathway showed 9.1% improvement in γ-PGA production. The NK-PO1 (pHT01-xylR) strain with the introduction of a metabolic toggle switch for controlling the expression of ODHC showed 66.2% higher

  4. Antibodies against vesicular stomatitis virus in horses from southern, midwestern and northeastern Brazilian States

    Directory of Open Access Journals (Sweden)

    Vinícius Leobet Lunkes

    2016-08-01

    Full Text Available ABSTRACT: Vesicular stomatitis virus (VSV is the agent of a vesicular disease that affects many animal species and may be clinically confounded with foot-and-mouth disease in ruminant and swine. Horses are especially susceptible to VSV and may serve as sentinels for virus circulation. The present study investigated the presence of neutralizing antibodies against VSV Indiana III (VSIV-3 in serum samples of 3,626 horses from six states in three Brazilian regions: Southern (RS, n = 1,011, Midwest (GO/DF, n = 1,767 and Northeast (PB, PE, RN and CE, n = 848 collected between 2013 and 2014. Neutralizing antibodies against VSIV-3 (titers ≥40 were detected in 641 samples (positivity of 17.7%; CI95%:16.5-19.0%, being 317 samples from CE (87.3%; CI95%: 83.4-90.5 %; 109 from RN (65.7%; CI95%: 57.8 -72.7%; 124 from PB (45.4%; CI95%: 39.4-51.5%; 78 from GO/DF (4.4%; CI95%: 3.5-5.5% and nine samples of RS (0.9%; CI95%: 0.4-1.7%. Several samples from the Northeast and Midwest harbored high neutralizing titers, indicating a recent exposure to the virus. In contrast, samples from RS had low titers, possibly due to a past remote exposure. Several positive samples presented neutralizing activity against other VSV serotypes (Indiana I and New Jersey, yet in lower titers, indicating the specificity of the response to VSIV-3. These results demonstrated a relatively recent circulation of VSIV-3 in northeastern Brazilian States, confirming clinical findings and demonstrating the sanitary importance of this infection.

  5. BIOCHEMICAL CHARACTERIZATION OF NATIVE USHER PROTEIN COMPLEXES FROM A VESICULAR SUBFRACTION OF TRACHEAL EPITHELIAL CELLS†

    Science.gov (United States)

    Zallocchi, Marisa; Sisson, Joseph H.; Cosgrove, Dominic

    2010-01-01

    Usher syndrome is the major cause of deaf/blindness in the world. It is a genetic heterogeneous disorder, with nine genes already identified as causative for the disease. We noted expression of all known Usher proteins in bovine tracheal epithelial cells, and exploited this system for large-scale biochemical analysis of Usher protein complexes. The dissected epithelia were homogenized in non-detergent buffer, and sedimented on sucrose gradients. At least two complexes were evident after the first gradient: one formed by specific isoforms of CDH23, PCDH15 and VLGR-1, and a different one at the top of the gradient that included all the Usher proteins and rab5, a transport vesicle marker. TEM analysis of these top fractions found them enriched in 100–200 nm vesicles, confirming a vesicular association of the Usher complex(es). Immunoisolation of these vesicles confirmed some of the associations already predicted and identified novel interactions. When the vesicles are lysed in the presence of phenylbutyrate, most of the Usher proteins co-sediment into the gradient at a sedimentation coefficient of approximately 50S, correlating with a predicted molecular mass of 2 × 106 Daltons. Although it is still unclear whether there is only one complex or several independent complexes that are trafficked within distinct vesicular pools, this work shows for the first time that native Usher proteins complexes occur in vivo. This complex(es) is present primarily in transport vesicles at the apical pole of tracheal epithelial cells, predicting that Usher proteins may be directionally transported as complexes in hair cells and photoreceptors. PMID:20058854

  6. Topical vesicular formulations of Curcuma longa extract on recuperating the ultraviolet radiation-damaged skin.

    Science.gov (United States)

    Kaur, Chanchal Deep; Saraf, Swarnlata

    2011-12-01

      Ultraviolet radiations generate reactive oxygen species, leading to adverse effects on skin properties. Botanical extracts are multifunctional in nature having various properties like photoprotection, anti-aging, moisturizing, antioxidant, astringent, anti-irritant, and antimicrobial activity.   The aim of this study was to formulate creams having Curcuma longa extract loaded novel vesicular systems (liposomes, ethosomes, and transfersomes) and study their photoprotective effect by assessment of skin hydration (Cutometer) and sebum content (Sebumeter).   The alcoholic C. longa extract loaded liposomes, ethosomes, and transfersomes having 0.5-2.0% w/w extract were prepared, evaluated for size, entrapment efficiency, and incorporated into the cream. Their long-term interaction with skin (6 weeks) was compared in terms of their effects on skin hydration and sebum content.   Vesicular size obtained was in the range 167.3 ± 3.0 to 262.4 ± 2.4 nm with low polydispersity index (0.2-0.3) and high entrapment efficiency. The efficacy was in the order C. longa extract loaded transfersomal creams > C. longa extract loaded ethosomal creams > C. longa extract loaded liposomal creams > C. longa extract loaded creams > Empty transfersome loaded cream > Empty ethosome loaded cream > Empty liposome loaded cream > Base cream.   The photoprotective properties of the constituents of C. longa extract and hydrant, moisturizing lipid components of nano vesicles with better skin penetration resulted in improvement in skin properties like skin hydration and sebum content. The herbal extract loaded nano vesicles incorporated in cream could be used as photoprotective formulations. © 2011 Wiley Periodicals, Inc.

  7. Potential fossil endoliths in vesicular pillow basalt, Coral Patch Seamount, eastern North Atlantic Ocean.

    Science.gov (United States)

    Cavalazzi, Barbara; Westall, Frances; Cady, Sherry L; Barbieri, Roberto; Foucher, Frédéric

    2011-09-01

    The chilled rinds of pillow basalt from the Ampère-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, which include filamentous and spherical microfossil-like structures, were detected in K-phillipsite-filled amygdules within the chilled rinds. The filamentous structures (∼2.5 μm in diameter) occur as K-phillipsite tubules surrounded by an Fe-oxyhydroxide (lepidocrocite) rich membranous structure, whereas the spherical structures (from 4 to 2 μm in diameter) are associated with Ti oxide (anatase) and carbonaceous matter. Several lines of evidence indicate that the microfossil-like structures in the pillow basalt are the fossilized remains of microorganisms. Possible biosignatures include the carbonaceous nature of the spherical structures, their size distributions and morphology, the presence and distribution of native fluorescence, mineralogical and chemical composition, and environmental context. When taken together, the suite of possible biosignatures supports the hypothesis that the fossil-like structures are of biological origin. The vesicular microhabitat of the rock matrix is likely to have hosted a cryptoendolithic microbial community. This study documents a variety of evidence for past microbial life in a hitherto poorly investigated and underestimated microenvironment, as represented by the amygdules in the chilled pillow basalt rinds. This kind of endolithic volcanic habitat would have been common on the early rocky planets in our Solar System, such as Earth and Mars. This study provides a framework for evaluating traces of past life in vesicular pillow basalts, regardless of whether they occur on early Earth or Mars.

  8. Motor dysfunction in cerebellar Purkinje cell-specific vesicular GABA transporter knockout mice

    Directory of Open Access Journals (Sweden)

    Mikiko eKayakabe

    2014-01-01

    Full Text Available γ-Aminobutyric acid (GABA is a major inhibitory neurotransmitter in the adult mammalian central nervous system and plays modulatory roles in neural development. The vesicular GABA transporter (VGAT is an essential molecule for GABAergic neurotransmission due to its role in vesicular GABA release. Cerebellar Purkinje cells (PCs are GABAergic projection neurons that are indispensable for cerebellar function. To elucidate the significance of VGAT in cerebellar PCs, we generated and characterized PC-specific VGAT knockout (L7-VGAT mice. VGAT mRNAs and proteins were specifically absent in the 40-week-old L7-VGAT PCs. The morphological charactereistics, such as lamination and foliation of the cerebellar cortex, of the L7-VGAT mice were similar to those of the control littermate mice. Moreover, the protein expression levels and patterns of pre- (calbindin and parvalbumin and postsynaptic (GABA-A receptor α1 subunit (GABAARα1 and gephyrin molecules between the L7-VGAT and control mice were similar in the deep cerebellar nuclei that receive PC projections. However, the L7-VGAT mice performed poorly in the accelerating rotarod test and displayed ataxic gait in the footprint test. The L7-VGAT mice also exhibited severer ataxia as VGAT deficits progressed. These results suggest that VGAT in cerebellar Purkinje cells is not essential for the rough maintenance of cerebellar structure, but does play an important role in motor coordination. The L7-VGAT mice are a novel model of ataxia without PC degeneration, and would also be useful for studying the role of Purkinje cells in cognition and emotion.

  9. Molecular mechanisms of Sar/Arf GTPases in vesicular trafficking in yeast and plants.

    Science.gov (United States)

    Yorimitsu, Tomohiro; Sato, Ken; Takeuchi, Masaki

    2014-01-01

    Small GTPase proteins play essential roles in the regulation of vesicular trafficking systems in eukaryotic cells. Two types of small GTPases, secretion-associated Ras-related protein (Sar) and ADP-ribosylation factor (Arf), act in the biogenesis of transport vesicles. Sar/Arf GTPases function as molecular switches by cycling between active, GTP-bound and inactive, GDP-bound forms, catalyzed by guanine nucleotide exchange factors and GTPase-activating proteins, respectively. Activated Sar/Arf GTPases undergo a conformational change, exposing the N-terminal amphipathic α-helix for insertion into membranes. The process triggers the recruitment and assembly of coat proteins to the membranes, followed by coated vesicle formation and scission. In higher plants, Sar/Arf GTPases also play pivotal roles in maintaining the dynamic identity of organelles in the secretory pathway. Sar1 protein strictly controls anterograde transport from the endoplasmic reticulum (ER) through the recruitment of plant COPII coat components onto membranes. COPII vesicle transport is responsible for the organization of highly conserved polygonal ER networks. In contrast, Arf proteins contribute to the regulation of multiple trafficking routes, including transport through the Golgi complex and endocytic transport. These transport systems have diversified in the plant kingdom independently and exhibit several plant-specific features with respect to Golgi organization, endocytic cycling, cell polarity and cytokinesis. The functional diversification of vesicular trafficking systems ensures the multicellular development of higher plants. This review focuses on the current knowledge of Sar/Arf GTPases, highlighting the molecular details of GTPase regulation in vesicle formation in yeast and advances in knowledge of the characteristics of vesicle trafficking in plants.

  10. Molecular mechanisms of Sar/Arf GTPases in vesicular trafficking in yeast and plants

    Directory of Open Access Journals (Sweden)

    Tomohiro eYorimitsu

    2014-08-01

    Full Text Available Small GTPase proteins play essential roles in the regulation of vesicular trafficking systems in eukaryotic cells. Two types of small GTPases, secretion-associated Ras-related protein (Sar and ADP-ribosylation factor (Arf, act in the biogenesis of transport vesicles. Sar/Arf GTPases function as molecular switches by cycling between active, GTP-bound and inactive, GDP-bound forms, catalyzed by guanine nucleotide exchange factors and GTPase-activating proteins, respectively. Activated Sar/Arf GTPases undergo a conformational change, exposing the N-terminal amphipathic α-helix for insertion into membranes. The process triggers the recruitment and assembly of coat proteins to the membranes, followed by coated vesicle formation and scission. In higher plants, Sar/Arf GTPases also play pivotal roles in maintaining the dynamic identity of organelles in the secretory pathway. Sar1 GTPase strictly controls anterograde transport from the endoplasmic reticulum (ER through the recruitment of plant COPII coat components onto membranes. COPII vesicle transport is responsible for the organization of highly conserved polygonal ER networks. In contrast, Arf GTPases contribute to the regulation of multiple trafficking routes, including transport through the Golgi complex and endocytic transport. These transport systems have diversified in the plant kingdom independently and exhibit several plant-specific features with respect to Golgi organization, endocytic cycling, cell polarity and cytokinesis. The functional diversification of vesicular trafficking systems ensures the multicellular development of higher plants. This review focuses on the current knowledge of Sar/Arf GTPases, highlighting the molecular details of GTPase regulation in vesicle formation in yeast and advances in knowledge of the characteristics of vesicle trafficking in plants.

  11. Developing ultra deformable vesicular transportation of a bioactive alkaloid in pursuit of vitiligo therapy

    Directory of Open Access Journals (Sweden)

    Vinod KR

    2012-08-01

    Full Text Available Objective: To develop transfersomal formulation integrated with piperine intended for vitiligo. Methods: Film hydration technique was employed in the preparation of transfersomes. Modified diffusion cell, consistency tester were fabricated for ex vivo diffusion studies and spreadability studies respectively while tape stripping method was integrated with tissue extraction in the determination of tissue drug concentration. Results: When film hydration technique was used for, ultradeformable vesicles (transfersomes of piperine in soabean phosphatidylcholine was formed with (67.11依0.22 to (70.55依3.62 and (60.12依1.04 to (80.43依0.14 mean size (毺 m and entrapment efficiency (% respectively. Transfersomes are capable of crossing the pores in permeability barriers extremely efficient even if the transfersome radius (tr is much greater than the pore size (rpore ie., tr/rpore曒0.25 the driven flux rate depends on the transdermal osmotic gradient. The vesicles describes elasto-mechanical character of vesicles while penetrating through the pores. The proviso is that the vesicular membrane elasticity is dynamically to the local stress by the external. Diffusion and Spreadability studies showed maximum diffusion when the lipid was kept minimum. Tape stripping and tissue extraction method for the tissue drug retention showed that (75.25依1.72% drug was retained in the dermis. Conclusions: Span 80 was preferred over tween 80 in terms of dermal retention. Size and encapsulation was slightly altered by phosphatidylcholine concentration. The kinetics, efficiency and the transfersome mediated transport can be tailored for trans-epidermal, deep tissues and systemic depending on the vesicular composition, dose and form. Thus we have offered a successful drug delivery of piperine targeting the deep epidermis.

  12. Pathogenesis of experimental vesicular stomatitis virus (New Jersey serotype) infection in the deer mouse (Peromyscus maniculatus).

    Science.gov (United States)

    Cornish, T E; Stallknecht, D E; Brown, C C; Seal, B S; Howerth, E W

    2001-07-01

    The pathogenesis of vesicular stomatitis virus (VSV) infection has not been investigated previously in native New World rodents that may have a role in the epidemiology of the disease. In the present study, 45 juvenile and 80 adult deer mice (Peromyscus maniculatus) were inoculated intranasally with VSV New Jersey serotype (VSV-NJ) and examined sequentially over a 7-day period. Virus was detected by means of immunohistochemistry and in situ hybridization in all tissues containing histologic lesions. Viral antigen and mRNA were observed initially in olfactory epithelium neurons, followed by olfactory bulbs and more caudal olfactory pathways in the brain. Virus also was detected throughout the ventricular system in the brain and central canal of the spinal cord. These results support both viral retrograde transneuronal transport and viral spread within the ventricular system. Other tissues containing viral antigen included airway epithelium and macrophages in the lungs, cardiac myocytes, and macrophages in cervical lymph nodes. In a second experiment, 15 adult, 20 juvenile, and 16 nestling deer mice were inoculated intradermally with VSV-NJ. Adults were refractory to infection by this route; however, nestlings and juveniles developed disseminated central nervous system infections. Viral antigen also was detected in cardiac myocytes and lymph node macrophages in these animals. Viremia was detected by virus isolation in 35/72 (49%) intranasally inoculated juvenile and adult mice and in 17/36 (47%) intradermally inoculated nestlings and juveniles from day 1 to day 3 postinoculation. The documentation of viremia in these animals suggests that they may have a role in the epidemiology of vector-borne vesicular stomatitis.

  13. Leucine-rich repeat-containing G protein-coupled receptor 4 facilitates vesicular stomatitis virus infection by binding vesicular stomatitis virus glycoprotein.

    Science.gov (United States)

    Zhang, Na; Huang, Hongjun; Tan, Binghe; Wei, Yinglei; Xiong, Qingqing; Yan, Yan; Hou, Lili; Wu, Nannan; Siwko, Stefan; Cimarelli, Andrea; Xu, Jianrong; Han, Honghui; Qian, Min; Liu, Mingyao; Du, Bing

    2017-10-06

    Vesicular stomatitis virus (VSV) and rabies and Chandipura viruses belong to the Rhabdovirus family. VSV is a common laboratory virus to study viral evolution and host immune responses to viral infection, and recombinant VSV-based vectors have been widely used for viral oncolysis, vaccination, and gene therapy. Although the tropism of VSV is broad, and its envelope glycoprotein G is often used for pseudotyping other viruses, the host cellular components involved in VSV infection remain unclear. Here, we demonstrate that the host protein leucine-rich repeat-containing G protein-coupled receptor 4 (Lgr4) is essential for VSV and VSV-G pseudotyped lentivirus (VSVG-LV) to infect susceptible cells. Accordingly, Lgr4-deficient mice had dramatically decreased VSV levels in the olfactory bulb. Furthermore, Lgr4 knockdown in RAW 264.7 cells also significantly suppressed VSV infection, and Lgr4 overexpression in RAW 264.7 cells enhanced VSV infection. Interestingly, only VSV infection relied on Lgr4, whereas infections with Newcastle disease virus, influenza A virus (A/WSN/33), and herpes simplex virus were unaffected by Lgr4 status. Of note, assays of virus entry, cell ELISA, immunoprecipitation, and surface plasmon resonance indicated that VSV bound susceptible cells via the Lgr4 extracellular domain. Pretreating cells with an Lgr4 antibody, soluble LGR4 extracellular domain, or R-spondin 1 blocked VSV infection by competitively inhibiting VSV binding to Lgr4. Taken together, the identification of Lgr4 as a VSV-specific host factor provides important insights into understanding VSV entry and its pathogenesis and lays the foundation for VSV-based gene therapy and viral oncolytic therapeutics. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Expression of the human isoform of glutamate dehydrogenase, hGDH2, augments TCA cycle capacity and oxidative metabolism of glutamate during glucose deprivation in astrocytes

    DEFF Research Database (Denmark)

    Nissen, Jakob D; Lykke, Kasper; Bryk, Jaroslaw

    2017-01-01

    -expressing transgenic mice. We measured glutamate uptake and metabolism using [(3) H]glutamate, while the effect on metabolic pathways of glutamate and glucose was evaluated by use of (13) C and (14) C substrates and analysis by mass spectrometry and determination of radioactively labeled metabolites...

  15. Neonatal monosodium glutamate treatment modifies glutamic acid decarboxylase activity during rat brain postnatal development.

    Science.gov (United States)

    Ureña-Guerrero, Mónica Elisa; López-Pérez, Silvia Josefina; Beas-Zárate, Carlos

    2003-03-01

    Monosodium glutamate (MSG) produces neurodegeneration in several brain regions when it is administered to neonatal rats. From an early embryonic age to adulthood, GABA neurons appear to have functional glutamatergic receptors, which could convert them in an important target for excitotoxic neurodegeneration. Changes in the activity of the GABA synthesizing enzyme, glutamic acid decarboxylase (GAD), have been shown after different neuronal insults. Therefore, this work evaluates the effect of neonatal MSG treatment on GAD activity and kinetics in the cerebral cortex, striatum, hippocampus and cerebellum of the rat brain during postnatal development. Neonatal MSG treatment decreased GAD activity in the cerebral cortex at 21 and 60 postnatal days (PD), mainly due to a reduction in the enzyme affinity (K(m)). In striatum, the GAD activity and the enzyme maximum velocity (V(max)) were increased at PD 60 after neonatal MSG treatment. Finally, in the hippocampus and cerebellum, the GAD activity and V(max) were increased, but the K(m) was found to be lower in the experimental group. The results could be related to compensatory mechanisms from the surviving GABAergic neurons, and suggest a putative adjustment in the GAD isoform expression throughout the development of the postnatal brain, since this enzyme is regulated by the synaptic activity under physiological and/or pathophysiological conditions.

  16. Monosodium glutamate alters the response properties of rat trigeminovascular neurons through activation of peripheral NMDA receptors.

    Science.gov (United States)

    O'Brien, Melissa; Cairns, Brian E

    2016-10-15

    Ingestion of monosodium glutamate (MSG) has been shown to cause headaches in healthy individuals and trigger migraine-like headaches in migraine sufferers. We combined immunohistochemistry, in vivo electrophysiology, and laser Doppler recordings of dural vasculature to investigate the effect of systemic administration of MSG on the trigeminovascular pathway. Immunohistochemical analysis confirmed the expression of NMDA receptors on nerve fibers innervating dural blood vessels and excitatory amino acid transporter 2 on dural blood vessels. Systemic administration of MSG (50mg/kg) evoked an increase in ongoing discharge in 5/6 spinal trigeminal subnucleus caudalis (SpVc) neurons with dural input recorded from male and female rats, respectively, as well as lowering their mechanical activation threshold. There were no sex-related differences in these effects of MSG. Neuronal discharge and mechanical sensitization were significantly attenuated by co-injection with the peripherally restricted NMDA receptor antagonist (2R)-amino-5-phosphonovaleric acid (APV) in both sexes. Systemic administration of MSG induced a 24.5% and 20.6% increase in dural flux in male and female rats, respectively. These results suggest that MSG-induced headache is mediated by the activation of peripheral NMDA receptors and subsequent dural vasodilation. Peripheral NMDA receptors are a potential target for the development of new drugs to treat headaches. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Increased pain and muscle glutamate concentration after single ingestion of monosodium glutamate by myofascial temporomandibular disorders patients.

    Science.gov (United States)

    Shimada, A; Castrillon, E E; Baad-Hansen, L; Ghafouri, B; Gerdle, B; Wåhlén, K; Ernberg, M; Cairns, B E; Svensson, P

    2016-10-01

    A randomized, double-blinded, placebo-controlled study was conducted to investigate if single monosodium glutamate (MSG) administration would elevate muscle/serum glutamate concentrations and affect muscle pain sensitivity in myofascial temporomandibular disorders (TMD) patients more than in healthy individuals. Twelve myofascial TMD patients and 12 sex- and age-matched healthy controls participated in two sessions. Participants drank MSG (150 mg/kg) or NaCl (24 mg/kg; control) diluted in 400 mL of soda. The concentration of glutamate in the masseter muscle, blood plasma and saliva was determined before and after the ingestion of MSG or control. At baseline and every 15 min after the ingestion, pain intensity was scored on a 0-10 numeric rating scale. Pressure pain threshold, pressure pain tolerance (PPTol) and autonomic parameters were measured. All participants were asked to report adverse effects after the ingestion. In TMD, interstitial glutamate concentration was significantly greater after the MSG ingestion when compared with healthy controls. TMD reported a mean pain intensity of 2.8/10 at baseline, which significantly increased by 40% 30 min post MSG ingestion. At baseline, TMD showed lower PPTols in the masseter and trapezius, and higher diastolic blood pressure and heart rate than healthy controls. The MSG ingestion resulted in reports of headache by half of the TMD and healthy controls, respectively. These findings suggest that myofascial TMD patients may be particularly sensitive to the effects of ingested MSG. WHAT DOES THIS STUDY ADD?': Elevation of interstitial glutamate concentration in the masseter muscle caused by monosodium glutamate (MSG) ingestion was significantly greater in myofascial myofascial temporomandibular disorders (TMD) patients than healthy individuals. This elevation of interstitial glutamate concentration in the masseter muscle significantly increased the intensity of spontaneous pain in myofascial TMD patients. © 2016

  18. Differential effects of repetitive oral administration of monosodium glutamate on interstitial glutamate concentration and muscle pain sensitivity.

    Science.gov (United States)

    Shimada, Akiko; Baad-Hansen, Lene; Castrillon, Eduardo; Ghafouri, Bijar; Stensson, Niclas; Gerdle, Björn; Ernberg, Malin; Cairns, Brian; Svensson, Peter; Svensson Odont, Peter

    2015-02-01

    The aim of this study was to determine the relationship of high daily monosodium glutamate (MSG) consumption with glutamate concentrations in jaw muscle, saliva, and serum, and muscle pain sensitivity in healthy participants. A randomized, double-blinded, placebo-controlled study was conducted to investigate the effect of repetitive consumption of high-dose MSG on glutamate concentration in the masseter muscles measured by microdialysis and muscle pain sensitivity. In five contiguous experimental daily sessions, 32 healthy participants drank MSG (150 mg/kg) or NaCl (24 mg/kg) diluted with a 400 mL soda. The concentrations of glutamate before and after the ingestion were assessed in dialysate and plasma samples on the first and last days. Saliva glutamate concentration was assessed every day. Pressure pain threshold, pressure pain tolerance, autonomic parameters (heart rate, systolic and diastolic blood pressures) and reported side effects also were assessed. No significant change was noted in the baseline concentration of glutamate in the masseter muscle, blood, or saliva, but the peak concentration in the masseter muscle increased significantly between day 1 and 5. A statistically significant increase in systolic and diastolic blood pressures after MSG administration was observed, as well as a significantly higher frequency of reports of nausea and headache in the MSG group. No robust effect of MSG on muscle sensitivity was found. Interstitial glutamate concentration in the masseter muscle is not highly disturbed by excessive repetitive intake of MSG in healthy man. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Monosodium glutamate induced histomorphometric changes in thyroid gland of adult

    Directory of Open Access Journals (Sweden)

    Pooja Rani1, Kamlesh Khatri2, Renu Chauhan1

    2013-08-01

    Full Text Available Monosodium Glutamate (MSG is widely used as a flavor enhanc-er throughout the world. MSG contains glutamic acid, sodium and water. Glutamic acid serves as a neurotransmitter vital to the transmission of nerve impulses in many parts of the central nerv-ous system, and in excess it may cause neurotoxicity leading to endocrinal disorders. The present study was conducted to eva-luate histomorphometrically the effects of monosodium glutamate on the thyroid gland of adult albino rats. The experimental group was given 4mg/g body weight of monosodium glutamate intra-peritoneally for seven days. Controls were maintained. After thirty days of the last dose, all the animals were sacrificed, their thyroid glands were dissected out, processed and sections stained with haematoxylin and eosin (H&E and Periodic Acid Schiff (PAS and examined for histomorphometry under Zeiss light microscope and Image Pro-Express Analyzer. The results of the present study showed a significant increase in the body weight of the MSG treated animals, although these animals consumed less food than the controls. A significant increase in the size of the follicles ac-companied by an increase in the mean height and area of the folli-cular cells and decreased colloid in some of the follicles was ob-served, pointing towards an increase in thyroid gland activity.

  20. Glutamate excitotoxicity inflicts paranodal myelin splitting and retraction.

    Science.gov (United States)

    Fu, Yan; Sun, Wenjing; Shi, Yunzhou; Shi, Riyi; Cheng, Ji-Xin

    2009-08-20

    Paranodal myelin damage is observed in white matter injury. However the culprit for such damage remains unknown. By coherent anti-Stokes Raman scattering imaging of myelin sheath in fresh tissues with sub-micron resolution, we observed significant paranodal myelin splitting and retraction following glutamate application both ex vivo and in vivo. Multimodal multiphoton imaging further showed that glutamate application broke axo-glial junctions and exposed juxtaparanodal K+ channels, resulting in axonal conduction deficit that was demonstrated by compound action potential measurements. The use of 4-aminopyridine, a broad-spectrum K+ channel blocker, effectively recovered both the amplitude and width of compound action potentials. Using CARS imaging as a quantitative readout of nodal length to diameter ratio, the same kind of paranodal myelin retraction was observed with applications of Ca2+ ionophore A23187. Moreover, exclusion of Ca2+ from the medium or application of calpain inhibitor abolished paranodal myelin retraction during glutamate exposure. Examinations of glutamate receptor agonists and antagonists further showed that the paranodal myelin damage was mediated by NMDA and kainate receptors. These results suggest that an increased level of glutamate in diseased white matter could impair paranodal myelin through receptor-mediated Ca2+ overloading and subsequent calpain activation.

  1. Glutamate excitotoxicity inflicts paranodal myelin splitting and retraction.

    Directory of Open Access Journals (Sweden)

    Yan Fu

    2009-08-01

    Full Text Available Paranodal myelin damage is observed in white matter injury. However the culprit for such damage remains unknown. By coherent anti-Stokes Raman scattering imaging of myelin sheath in fresh tissues with sub-micron resolution, we observed significant paranodal myelin splitting and retraction following glutamate application both ex vivo and in vivo. Multimodal multiphoton imaging further showed that glutamate application broke axo-glial junctions and exposed juxtaparanodal K+ channels, resulting in axonal conduction deficit that was demonstrated by compound action potential measurements. The use of 4-aminopyridine, a broad-spectrum K+ channel blocker, effectively recovered both the amplitude and width of compound action potentials. Using CARS imaging as a quantitative readout of nodal length to diameter ratio, the same kind of paranodal myelin retraction was observed with applications of Ca2+ ionophore A23187. Moreover, exclusion of Ca2+ from the medium or application of calpain inhibitor abolished paranodal myelin retraction during glutamate exposure. Examinations of glutamate receptor agonists and antagonists further showed that the paranodal myelin damage was mediated by NMDA and kainate receptors. These results suggest that an increased level of glutamate in diseased white matter could impair paranodal myelin through receptor-mediated Ca2+ overloading and subsequent calpain activation.

  2. Influence of glutamic acid enantiomers on C-mineralization.

    Science.gov (United States)

    Formánek, Pavel; Vranová, Valerie; Lojková, Lea

    2015-02-01

    Seasonal dynamics in the mineralization of glutamic acid enantiomers in soils from selected ecosystems was determined and subjected to a range of treatments: ambient x elevated CO2 level and meadow x dense x thinned forest environment. Mineralization of glutamic acid was determined by incubation of the soil with 2 mg L- or D-glutamic acid g(-1) of dry soil to induce the maximum respiration rate. Mineralization of glutamic acid enantiomers in soils fluctuates over the course of a vegetation season, following a similar trend across a range of ecosystems. Mineralization is affected by environmental changes and management practices, including elevated CO2 level and thinning intensity. L-glutamic acid metabolism is more dependent on soil type as compared to metabolism of its D-enantiomer. The results support the hypothesis that the slower rate of D- compared to L- amino acid mineralization is due to different roles in anabolism and catabolism of the soil microbial community. © 2014 Wiley Periodicals, Inc.

  3. The genetics of schizophrenia: glutamate not dopamine?

    Science.gov (United States)

    Collier, David A; Li, Tao

    2003-11-07

    The major targets of current drugs used in mental health, such as neurotransmitter receptors and transporters, are based on serendipitous findings from several decades ago, and there is currently a severe drought of new drug targets. There is a pressing need for novel drugs, and much hope has been placed on the use of molecular genetics to help define them. However, despite evidence for a genetic basis to schizophrenia stretching back for over a century, and a heritability of about 80%, the identification of susceptibility genes has been an uphill struggle. Candidate gene studies, which have generally focussed on obvious candidates from the dopamine and serotonin systems, as well as genes involved in brain development, have not generally been successful, although meta-analysis indicates that the dopamine D3 receptor gene (DRD3) and the serotonin receptor gene type 2A (HTR2A) may have a very small influence on risk. Linkage analysis has provided robust evidence of genetic loci, for example, on chromosomes 8p, 13q and 22q, and also implies shared genetic aetiology with bipolar disorder. The identification of these loci together with advances in genetic technology, especially the characterisation of polymorphisms, the understanding of haplotypes and the development of statistical methods, has lead to the identification of several plausible susceptibility genes, including neuregulin 1, proline dehydrogenase and dysbindin. Interestingly, these genes point more towards a role for the glutamate pathway rather than the dopamine pathway in schizophrenia. We have attempted to replicate some of these findings in schizophrenic patients from SW China, and we find significant association with a novel neuregulin 1 haplotype, with proline dehydrogenase polymorphisms, but not with catechol-O-methyltransferase (COMT). The replication of neuregulin 1 association on chromosome 8p by several investigators is the most convincing to date, and the presence of a syndrome similar to

  4. Strains of Lentinula edodes suppress growth of phytopathogenic fungi and inhibit Alagoas serotype of vesicular stomatitis virus Linhagens de Lentinula edodes inibem fungos fitopatogênicos e o vírus da estomatite vesicular, sorotipo Alagoas

    OpenAIRE

    Sasaki, Selma H.; Rosa E.C. Linhares; Nozawa,Carlos M.; Ricardo Montalván; Paccola-Meirelles,Luzia D.

    2001-01-01

    Four Lentinula edodes strains (Le10, 46, K2, Assai) were assessed for their antagonistic effect on four filamentous fungus species of agricultural importance (Helminthosporium euphorbiae, Helminthosporium sp, Fusarium solani and Phomopsis sojae) and on Alagoas serotype of Vesicular Stomatitis Virus (VSA). The L. edodes strains studied had variable effects on the filamentous fungi and on VSA. The K2 and Le10 strains were antagonistic on the fungi assessed and the 46 and K2 strains were efficie...

  5. The involvement of glutamate in the pathophysiology of depression.

    Science.gov (United States)

    Palucha, A; Pilc, A

    2005-05-01

    In spite of more than 40 years of thorough studies, conventional antidepressants still have many limitations that hinder the effective treatment of depression. It seems that a breakthrough in the therapy of depression will require going beyond a monoamine-based theory of depression. Converging lines of evidence indicate that the glutamatergic system might be a promising target for a novel antidepressant therapy. Both ionotropic glutamate receptor ligands (functional NMDA receptor antagonists and AMPA receptor potentiators) and compounds acting at metabotropic glutamate receptors (mGluRs; group I mGluR antagonists, group II antagonists and group III agonists) produce antidepressant-like activity in several preclinical and some clinical studies. In this review, current knowledge and crucial hypotheses concerning the role of glutamate in the pathophysiology of depression are discussed. 2005 Prous Science. All rights reserved

  6. Foreign body granuloma caused by monosodium glutamate after BCG vaccination.

    Science.gov (United States)

    Chiu, Yao-Kun; Huang, Chao-Cheng; Jeng, Jingyueh; Shiea, Jentaie; Chen, Wei-Jen

    2006-08-01

    We describe a 7-month-old male infant with a foreign body granuloma caused by monosodium glutamate (MSG) after a Bacille Calmette-Guérin (BCG) immunization. A ridged, erythematous, indurated plaque developed over a BCG injection site on his left upper arm 1 month after the first BCG immunization. Biopsy showed multiple noncaseating foreign body granulomas without detectable mycobacteria by both Ziehl-Neelsen stain and polymerase chain reaction assay. Birefringent crystals were identified in the foreign body giant cells with polarized light microscopy. The crystals were further determined to be glutamic acid by the method of fast atom bombardment. Hence, MSG, the only composite of BCG vaccine except the bacillus, was believed to be responsible for the granulomatous foreign body reaction. On review of the literature, we could find no previous report of an adverse reaction of BCG immunization attributable to MSG (glutamic acid).

  7. [PECULIARITIES OF THE CEREBROVASCULAR EFFECTS OF GLUTAMIC ACID].

    Science.gov (United States)

    Gan'shina, T S; Kurza, E V; Kurdyumov, I N; Maslennikov, D V; Mirzoyan, R S

    2016-01-01

    Experiments on nonlinear rats subjected to global transient cerebral ischemia revealed the ability of glutamic acid to improve cerebral circulation. Consequently, the excitatory amino acid can produce adverse (neurotoxic) and positive (anti-ischemic) effects in cerebral ischemia. The cerebrovascular effect of glutamic acid in cerebral ischemia is attenuated on the background action of the MNDA receptor blocker MK-801 (0.5 mg/kg intravenously) and eliminated by bicuculline. When glutamic acid is combined with the non-competitive MNDA receptor antagonist MK-801, neither one nor another drug shows its vasodilator effect. The results are indicative of the interaction between excitatory and inhibitory systems on the level of cerebral vessels and once again confirm our previous conclusion about the decisive role of GABA(A) receptors in brain vessels in the implementation of anti-ischemic activity of endogenous compounds (melatonin) and well-known pharmacological substances (mexidol, afobazole), and new chemical compounds based on GABA-containing lipid derivatives.

  8. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

    Directory of Open Access Journals (Sweden)

    Guillermo Hugo Peralta

    Full Text Available ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

  9. Chronic glutamate toxicity in neurodegenerative diseases-what is the evidence?

    Directory of Open Access Journals (Sweden)

    Pamela eMaher

    2015-12-01

    Full Text Available Together with aspartate, glutamate is the major excitatory neurotransmitter in the brain. Glutamate binds and activates both ligand-gated ion channels (ionotropic glutamate receptors and a class of G-protein coupled receptors (metabotropic glutamate receptors. Although the intracellular glutamate concentration in the brain is in the millimolar range, the extracellular glutamate concentration is kept in the low micromolar range by the action of excitatory amino acid transporters that import glutamate and aspartate into astrocytes and neurons. Excess extracellular glutamate may lead to excitotoxicity in vitro and in vivo in acute insults like ischemic stroke via the overactivation of ionotropic glutamate receptors. In addition, chronic excitotoxicity has been hypothesized to play a role in numerous neurodegenerative diseases including amyotrophic lateral sclerosis, Alzheimer’s disease and Huntington’s disease. Based on this hypothesis, a good deal of effort has been devoted to develop and test drugs that either inhibit glutamate receptors or decrease extracellular glutamate. In this review, we provide an overview of the different pathways that are thought to lead to an over-activation of the glutamatergic system and glutamate toxicity in neurodegeneration. In addition, we summarize the available experimental evidence for glutamate toxicity in animal models of neurodegenerative diseases.

  10. Enzymatic production of α-ketoglutaric acid from l-glutamic acid via l-glutamate oxidase.

    Science.gov (United States)

    Niu, Panqing; Dong, Xiaoxiang; Wang, Yuancai; Liu, Liming

    2014-06-10

    In this study, a novel strategy for α-ketoglutaric acid (α-KG) production from l-glutamic acid using recombinant l-glutamate oxidase (LGOX) was developed. First, by analyzing the molecular structure characteristics of l-glutamic acid and α-KG, LGOX was found to be the best catalyst for oxidizing the amino group of l-glutamic acid to a ketonic group without the need for exogenous cofactor. Then the LGOX gene was expressed in Escherichia coli BL21 (DE3) in a soluble and active form, and the recombinant LGOX activity reached to a maximum value of 0.59U/mL at pH 6.5, 30°C. Finally, the maximum α-KG concentration reached 104.7g/L from 110g/L l-glutamic acid in 24h, under the following optimum conditions: 1.5U/mL LGOX, 250U/mL catalase, 3mM MnCl2, 30°C, and pH 6.5. Copyright © 2014. Published by Elsevier B.V.

  11. Changes in Susceptibility to Oncolytic Vesicular Stomatitis Virus during Progression of Prostate Cancer.

    Science.gov (United States)

    Yu, Nanmeng; Puckett, Shelby; Antinozzi, Peter A; Cramer, Scott D; Lyles, Douglas S

    2015-05-01

    A major challenge to oncolytic virus therapy is that individual cancers vary in their sensitivity to oncolytic viruses, even when these cancers arise from the same tissue type. Variability in response may arise due to differences in the initial genetic lesions leading to cancer development. Alternatively, susceptibility to viral oncolysis may change during cancer progression. These hypotheses were tested using cells from a transgenic mouse model of prostate cancer infected with vesicular stomatitis virus (VSV). Primary cultures from murine cancers derived from prostate-specific Pten deletion contained a mixture of cells that were susceptible and resistant to VSV. Castration-resistant cancers contained a higher percentage of susceptible cells than cancers from noncastrated mice. These results indicate both susceptible and resistant cells can evolve within the same tumor. The role of Pten deletion was further investigated using clonal populations of murine prostate epithelial (MPE) progenitor cells and tumor-derived Pten(-/-) cells. Deletion of Pten in MPE progenitor cells using a lentivirus vector resulted in cells that responded poorly to interferon and were susceptible to VSV infection. In contrast, tumor-derived Pten(-/-) cells expressed higher levels of the antiviral transcription factor STAT1, activated STAT1 in response to VSV, and were resistant to VSV infection. These results suggest that early in tumor development following Pten deletion, cells are primarily sensitive to VSV, but subsequent evolution in tumors leads to development of cells that are resistant to VSV infection. Further evolution in castration-resistant tumors leads to tumors in which cells are primarily sensitive to VSV. There has been a great deal of progress in the development of replication-competent viruses that kill cancer cells (oncolytic viruses). However, a major problem is that individual cancers vary in their sensitivity to oncolytic viruses, even when these cancers arise from the

  12. Historia natural del virus de la estomatitis vesicular en zonas enzoóticas de Antioquia

    Directory of Open Access Journals (Sweden)

    John Arboleda

    2003-01-01

    Full Text Available

    La Estomatitis Vesicular (EV es una enfermedad producida
    por el virus de la Estomatitis Vesicular, serotipos New Jersey (VSV-NJ e Indiana (VSV-IN, afecta bovinos y equinos, porcinos y causa infección natural en humanos, principalmente granjeros, ordeñadores y personal de laboratorio.
    Se caracteriza por producir vesículas en las membranas mucosas
    de la boca (epitelio de la lengua y el paladar, bandas coronarias,
    pezones y tejidos blandos de los cascos; hay pérdida de peso y decrecimiento en la producción de leche. Está clasificada en la Lista A de la Organización Internacional de Epizootias, debido a su gran poder de difusión, a las graves consecuencias socioeconómicas y a las restricciones comerciales. Además, clínicamente la EV es indistinguible de la Fiebre Aftosa (FA (1.
    La enfermedad se presenta por ciclos estacionales; la mayoría
    de ellos ocurre en las épocas de transición de los períodos de lluvias a los de verano y viceversa (2. Estudios serológicos realizados en áreas endémicas han demostrado que VSV-NJ y VSV-IN infectan en forma natural una amplia variedad de animales silvestres, los cuales están posiblemente implicados en la ecozootiología de la EV, bien como hospederos portadores, amplificadores o reservorios. Igualmente, dos especies de artrópodos, Lutzomyia shannoni y Simulium vittatum son infectados naturalmente, replican y transmiten experimentalmente
    el VSV, convirtiéndolos en posibles vectores y/o reservorios.
    Sin embargo, en ningún animal se produce la viremia necesaria para infectar los artrópodos hematófagos. El reservorio natural nunca ha sido encontrado entre los animales domésticos y silvestres investigados (3.

    El objetivo es identificar los factores ecológicos (cobertura
    vegetal, temperatura promedio, pluviosidad y humedad relativa, los vectores artrópodos y los mamíferos reservorios asociados con el antenimiento y transmisión de la VSV en

  13. Therapeutic effects of glutamic acid in piglets challenged with deoxynivalenol.

    Science.gov (United States)

    Wu, Miaomiao; Xiao, Hao; Ren, Wenkai; Yin, Jie; Tan, Bie; Liu, Gang; Li, Lili; Nyachoti, Charles Martin; Xiong, Xia; Wu, Guoyao

    2014-01-01

    The mycotoxin deoxynivalenol (DON), one of the most common food contaminants, primarily targets the gastrointestinal tract to affect animal and human health. This study was conducted to examine the protective function of glutamic acid on intestinal injury and oxidative stress caused by DON in piglets. Twenty-eight piglets were assigned randomly into 4 dietary treatments (7 pigs/treatment): 1) uncontaminated control diet (NC), 2) NC+DON at 4 mg/kg (DON), 3) NC+2% glutamic acid (GLU), and 4) NC+2% glutamic acid + DON at 4 mg/kg (DG). At day 15, 30 and 37, blood samples were collected to determine serum concentrations of CAT (catalase), T-AOC (total antioxidant capacity), H2O2 (hydrogen peroxide), NO (nitric oxide), MDA (maleic dialdehyde), DAO (diamine oxidase) and D-lactate. Intestinal morphology, and the activation of Akt/mTOR/4EBP1 signal pathway, as well as the concentrations of H2O2, MDA, and DAO in kidney, liver and small intestine, were analyzed at day 37. Results showed that DON significantly (Pglutamic acid supplementation according to the change of oxidative parameters in blood and tissues. Meanwhile, DON caused obvious intestinal injury from microscopic observations and permeability indicators, which was alleviated by glutamic acid supplementation. Moreover, the inhibition of DON on Akt/mTOR/4EBP1 signal pathway was reduced by glutamic acid supplementation. Collectively, these data suggest that glutamic acid may be a useful nutritional regulator for DON-induced damage manifested as oxidative stress, intestinal injury and signaling inhibition.

  14. Genomic convergence analysis of schizophrenia: mRNA sequencing reveals altered synaptic vesicular transport in post-mortem cerebellum.

    Directory of Open Access Journals (Sweden)

    Joann Mudge

    Full Text Available Schizophrenia (SCZ is a common, disabling mental illness with high heritability but complex, poorly understood genetic etiology. As the first phase of a genomic convergence analysis of SCZ, we generated 16.7 billion nucleotides of short read, shotgun sequences of cDNA from post-mortem cerebellar cortices of 14 patients and six, matched controls. A rigorous analysis pipeline was developed for analysis of digital gene expression studies. Sequences aligned to approximately 33,200 transcripts in each sample, with average coverage of 450 reads per gene. Following adjustments for confounding clinical, sample and experimental sources of variation, 215 genes differed significantly in expression between cases and controls. Golgi apparatus, vesicular transport, membrane association, Zinc binding and regulation of transcription were over-represented among differentially expressed genes. Twenty three genes with altered expression and involvement in presynaptic vesicular transport, Golgi function and GABAergic neurotransmission define a unifying molecular hypothesis for dysfunction in cerebellar cortex in SCZ.

  15. Tumor Necrosis Factor-Mediated Survival of CD169+ Cells Promotes Immune Activation during Vesicular Stomatitis Virus Infection

    DEFF Research Database (Denmark)

    Shinde, Prashant V; Xu, Haifeng C; Maney, Sathish Kumar

    2018-01-01

    Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169(+) cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169(+) cells during viral infections remain...... defense against viral pathogens. CD169(+) macrophages are shown to activate innate and adaptive immunity via "enforced virus replication" a controlled amplification of virus particles. However, factors regulating the CD169(+) macrophages remain to be studied. In this paper, we show that after Vesicular...... stomatitis virus infection, phagocytes produce tumor necrosis factor (TNF) which signals via TNFR1 and promote "enforced virus replication" in CD169(+) macrophages. Consequently, lack of TNF or TNFR1 resulted in defective immune activation and VSV clearance....

  16. Transcellular communication at the immunological synapse: a vesicular traffic-mediated mutual exchange [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Francesca Finetti

    2017-10-01

    Full Text Available The cell’s ability to communicate with the extracellular environment, with other cells, and with itself is a crucial feature of eukaryotic organisms. In the immune system, T lymphocytes assemble a specialized structure upon contact with antigen-presenting cells bearing a peptide-major histocompatibility complex ligand, known as the immunological synapse (IS. The IS has been extensively characterized as a signaling platform essential for T-cell activation. Moreover, emerging evidence identifies the IS as a device for vesicular traffic-mediated cell-to-cell communication as well as an active release site of soluble molecules. Here, we will review recent advances in the role of vesicular trafficking in IS assembly and focused secretion of microvesicles at the synaptic area in naïve T cells and discuss the role of the IS in transcellular communication.

  17. Antibodies to a recombinant glutamate-rich Plasmodium falciparum protein

    DEFF Research Database (Denmark)

    Hogh, B; Petersen, E; Dziegiel, M

    1992-01-01

    A Plasmodium falciparum antigen gene coding for a 220-kD glutamate-rich protein (GLURP) has been cloned, and the 783 C-terminal amino acids of this protein (GLURP489-1271) have been expressed as a beta-galactosidase fusion protein in Escherichia coli. The encoded 783 amino acid residues contain two...... areas of repeated amino acid sequences. Antibodies against recombinant GLURP489-1271, as well as against a synthetic peptide corresponding to GLURP899-916, and against a synthetic peptide representing the major glutamate rich repeat sequence from the P. falciparum ring erythrocyte surface antigen (Pf155...

  18. Populus euphratica APYRASE2 Enhances Cold Tolerance by Modulating Vesicular Trafficking and Extracellular ATP in Arabidopsis Plants1[OPEN

    Science.gov (United States)

    Deng, Shurong; Sun, Jian; Zhao, Rui; Ding, Mingquan; Zhang, Yinan; Sun, Yuanling; Wang, Wei; Tan, Yeqing; Liu, Dandan; Ma, Xujun; Hou, Peichen; Wang, Meijuan; Lu, Cunfu; Shen, Xin; Chen, Shaoliang

    2015-01-01

    Apyrase and extracellular ATP play crucial roles in mediating plant growth and defense responses. In the cold-tolerant poplar, Populus euphratica, low temperatures up-regulate APYRASE2 (PeAPY2) expression in callus cells. We investigated the biochemical characteristics of PeAPY2 and its role in cold tolerance. We found that PeAPY2 predominantly localized to the plasma membrane, but punctate signals also appeared in the endoplasmic reticulum and Golgi apparatus. PeAPY2 exhibited broad substrate specificity, but it most efficiently hydrolyzed purine nucleotides, particularly ATP. PeAPY2 preferred Mg2+ as a cofactor, and it was insensitive to various, specific ATPase inhibitors. When PeAPY2 was ectopically expressed in Arabidopsis (Arabidopsis thaliana), cold tolerance was enhanced, based on root growth measurements and survival rates. Moreover, under cold stress, PeAPY2-transgenic plants maintained plasma membrane integrity and showed reduced cold-elicited electrolyte leakage compared with wild-type plants. These responses probably resulted from efficient plasma membrane repair via vesicular trafficking. Indeed, transgenic plants showed accelerated endocytosis and exocytosis during cold stress and recovery. We found that low doses of extracellular ATP accelerated vesicular trafficking, but high extracellular ATP inhibited trafficking and reduced cell viability. Cold stress caused significant increases in root medium extracellular ATP. However, under these conditions, PeAPY2-transgenic lines showed greater control of extracellular ATP levels than wild-type plants. We conclude that Arabidopsis plants that overexpressed PeAPY2 could increase membrane repair by accelerating vesicular trafficking and hydrolyzing extracellular ATP to avoid excessive, cold-elicited ATP accumulation in the root medium and, thus, reduced ATP-induced inhibition of vesicular trafficking. PMID:26224801

  19. Populus euphratica APYRASE2 Enhances Cold Tolerance by Modulating Vesicular Trafficking and Extracellular ATP in Arabidopsis Plants.

    Science.gov (United States)

    Deng, Shurong; Sun, Jian; Zhao, Rui; Ding, Mingquan; Zhang, Yinan; Sun, Yuanling; Wang, Wei; Tan, Yeqing; Liu, Dandan; Ma, Xujun; Hou, Peichen; Wang, Meijuan; Lu, Cunfu; Shen, Xin; Chen, Shaoliang

    2015-09-01

    Apyrase and extracellular ATP play crucial roles in mediating plant growth and defense responses. In the cold-tolerant poplar, Populus euphratica, low temperatures up-regulate APYRASE2 (PeAPY2) expression in callus cells. We investigated the biochemical characteristics of PeAPY2 and its role in cold tolerance. We found that PeAPY2 predominantly localized to the plasma membrane, but punctate signals also appeared in the endoplasmic reticulum and Golgi apparatus. PeAPY2 exhibited broad substrate specificity, but it most efficiently hydrolyzed purine nucleotides, particularly ATP. PeAPY2 preferred Mg(2+) as a cofactor, and it was insensitive to various, specific ATPase inhibitors. When PeAPY2 was ectopically expressed in Arabidopsis (Arabidopsis thaliana), cold tolerance was enhanced, based on root growth measurements and survival rates. Moreover, under cold stress, PeAPY2-transgenic plants maintained plasma membrane integrity and showed reduced cold-elicited electrolyte leakage compared with wild-type plants. These responses probably resulted from efficient plasma membrane repair via vesicular trafficking. Indeed, transgenic plants showed accelerated endocytosis and exocytosis during cold stress and recovery. We found that low doses of extracellular ATP accelerated vesicular trafficking, but high extracellular ATP inhibited trafficking and reduced cell viability. Cold stress caused significant increases in root medium extracellular ATP. However, under these conditions, PeAPY2-transgenic lines showed greater control of extracellular ATP levels than wild-type plants. We conclude that Arabidopsis plants that overexpressed PeAPY2 could increase membrane repair by accelerating vesicular trafficking and hydrolyzing extracellular ATP to avoid excessive, cold-elicited ATP accumulation in the root medium and, thus, reduced ATP-induced inhibition of vesicular trafficking. © 2015 American Society of Plant Biologists. All Rights Reserved.

  20. Epizootic of vesicular disease in pigs caused by coxsackievirus B4 in the Soviet Union in 1975.

    Science.gov (United States)

    Lomakina, Natalia F; Shustova, Elena; Strizhakova, Olga M; Drexler, Felix; Lukashev, Alexander N

    2016-01-01

    Swine vesicular disease virus (SVDV) emerged around 1960 from a human enterovirus ancestor, coxsackievirus B5 (CVB5), and caused a series of epizootics in Europe and Asia. We characterized a coxsackievirus B4 strain that caused an epizootic involving 24 488 pigs in the Soviet Union in 1975. Phylogenetic evidence suggested that the swine virus emerged from a human ancestor between 1945 and 1975, almost simultaneously with the transfer of CVB5.

  1. Some Attenuated Variants of Vesicular Stomatitis Virus Show Enhanced Oncolytic Activity against Human Glioblastoma Cells relative to Normal Brain Cells▿

    OpenAIRE

    Wollmann, Guido; Rogulin, Vitaliy; Simon, Ian; Rose, John K.; van den Pol, Anthony N.

    2009-01-01

    Vesicular stomatitis virus (VSV) has been shown in laboratory studies to be effective against a variety of tumors, including malignant brain tumors. However, attenuation of VSV may be necessary to balance the potential toxicity toward normal cells, particularly when targeting brain tumors. Here we compared 10 recombinant VSV variants resulting from different attenuation strategies. Attenuations included gene shifting (VSV-p1-GFP/RFP), M protein mutation (VSV-M51), G protein cytoplasmic tail t...

  2. Pseudotyping Vesicular Stomatitis Virus with Lymphocytic Choriomeningitis Virus Glycoproteins Enhances Infectivity for Glioma Cells and Minimizes Neurotropism▿†

    OpenAIRE

    Muik, Alexander; Kneiske, Inna; Werbizki, Marina; Wilflingseder, Doris; Giroglou, Tsanan; Ebert, Oliver; Kraft, Anna; Dietrich, Ursula; Zimmer, Gert; Momma, Stefan; von Laer, Dorothee

    2011-01-01

    Vesicular stomatitis virus (VSV)-based oncolytic virotherapy has the potential to significantly improve the prognosis of aggressive malignancies such as brain cancer. However, VSV's inherent neurotoxicity has hindered clinical development so far. Given that this neurotropism is attributed to the glycoprotein VSV-G, VSV was pseudotyped with the nonneurotropic envelope glycoprotein of the lymphocytic choriomeningitis virus (LCMV-GP→VSV-GP). Compared to VSV, VSV-GP showed enhanced infectivity fo...

  3. Evaluation of the Protective Efficacy of Recombinant Vesicular Stomatitis Virus Vectors Against Marburg Hemorrhagic Fever in Nonhuman Primate Models

    Science.gov (United States)

    2007-01-19

    VSV (Simon, Cardomone et al. 1990), borna disease virus (Formella, Jehle et al. 2000), and Sinbis virus (Karpf, Lenches et al. 1997). The...C., et al. (2000). "Sequence variability of Borna disease virus : resistance to superinfection may contribute to high genome stability in...Marburg virus disease ". S Afr Med J 66(2):50-4 Roberts, A., L. Buonocore, et al. (1999). "Attenuated vesicular stomatitis viruses as vaccine vectors." J

  4. Laboratory bioassay for assessing the effects of sludge supernatant on plant growth and vesicular-arbuscular mycorrhiza formation

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, K.S.; Liberta, A.E.

    1982-12-01

    A laboratory bioassay is described for assessing the effects of sludge supernatant on juvenile corn growth and the ability of vesicular-arbuscular (VA) mycorrhizal fungi, indigenous to coal spoil, to form mycorrhizae. The bioassay demonstrated that application rates can be identified that have the potential to promote increased plant dry weight without suppressing the formation of VA mycorrhizae in a plant's root system.

  5. [Enzymatic production of α-ketoglutaric acid by L-glutamate oxidase from L-glutamic acid].

    Science.gov (United States)

    Niu, Panqing; Zhang, Zhenyu; Liu, Liming

    2014-08-01

    We produced α-ketoglutaric acid (α-KG) from L-glutamic acid, using enzymatic transformation approach with L-glutamate oxidase (LGOX). First, wild strain Streptomyces sp. FMME066 was mutated with NTG, a genetically stable mutant Streptomyces sp. FMME067 was obtained. Under the optimal nutrition conditions with fructose 10 g/L, peptone 7.5 g/L, KH2PO4 1 g/L and CaCl2 0.05 g/L, the maximum LGOX activity reached 0.14 U/mL. The LGOX was stable to pH and temperature, and Mn2+ had a stimulating effect. Finally, after 24 h enzymatic conversion under the optimal conditions, the maximum titer of α-KG reached 38.1 g/L from 47 g/L L-glutamic acid. Enzymatic transformation by LGOX is a potential approach for α-KG production.

  6. Complement selectively elicits glutamate release from nerve endings in different regions of mammal central nervous system.

    Science.gov (United States)

    Merega, Elisa; Di Prisco, Silvia; Lanfranco, Massimiliano; Severi, Paolo; Pittaluga, Anna

    2014-05-01

    Our study was aimed at investigating whether complement, a complex of soluble and membrane-associated serum proteins, could, in addition to its well-documented post-synaptic activity, also pre-synaptically affect the release of classic neurotransmitters in central nervous system (CNS). Complement (dilution 1 : 10 to 1 : 10000) elicited the release of preloaded [(3) H]-d-aspartate ([(3) H]d-ASP) and endogenous glutamate from mouse cortical synaptosomes in a dilution-dependent manner. It also evoked [(3) H]d-ASP release from mouse hippocampal, cerebellar, and spinal cord synaptosomes, as well as from rat and human cortical nerve endings, but left unaltered the release of GABA, [(3) H]noradrenaline or [(3) H]acetylcholine. Lowering external Na(+) (from 140 to 40 mM) or Ca(2+) (from 1.2 to 0.1 mM) ions prevented the 1 : 300 complement-evoked [(3) H]d-ASP release from mouse cortical synaptosomes. Complement-induced releasing effect was unaltered in synaptosomes entrapped with the Ca(2+) ions chelator 1,2-bis-(2-aminophenoxy) ethane-N,N,N',N', tetra-acetic acid or with pertussis toxin. Nifedipine,/ω-conotoxin GVIA/ω-conotoxin MVIIC mixture as well as the vesicular ATPase blocker bafilomycin A1 were also inefficacious. The excitatory amino acid transporter blocker DL-threo-ß-benzyloxyaspartic acid, on the contrary, reduced the complement-evoked releasing effect in a concentration-dependent manner. We concluded that complement-induced releasing activity is restricted to glutamatergic nerve endings, where it was accounted for by carrier-mediated release. Our observations afford new insights into the molecular events accounting for immune and CNS crosstalk. We investigated whether complement, a complex of soluble and membrane-associated serum proteins, could pre-synaptically affect the release of classic neurotransmitters in the central nervous system (CNS). Our data provide evidence that complement-induced releasing activity is restricted to glutamatergic nerve endings

  7. Regulation of monocarboxylic acid transporter-1 by cAMP dependent vesicular trafficking in brain microvascular endothelial cells.

    Science.gov (United States)

    Uhernik, Amy L; Li, Lun; LaVoy, Nathan; Velasquez, Micah J; Smith, Jeffrey P

    2014-01-01

    In this study, a detailed characterization of Monocarboxylic Acid Transporter-1 (Mct1) in cytoplasmic vesicles of cultured rat brain microvascular endothelial cells shows them to be a diverse population of endosomes intrinsic to the regulation of the transporter by a brief 25 to 30 minute exposure to the membrane permeant cAMP analog, 8Br-cAMP. The vesicles are heterogeneous in size, mobility, internal pH, and co-localize with discreet markers of particular types of endosomes including early endosomes, clathrin coated vesicles, caveolar vesicles, trans-golgi, and lysosomes. The vesicular localization of Mct1 was not dependent on its N or C termini, however, the size and pH of Mct1 vesicles was increased by deletion of either terminus demonstrating a role for the termini in vesicular trafficking of Mct1. Using a novel BCECF-AM based assay developed in this study, 8Br-cAMP was shown to decrease the pH of Mct1 vesicles after 25 minutes. This result and method were confirmed in experiments with a ratiometric pH-sensitive EGFP-mCherry dual tagged Mct1 construct. Overall, the results indicate that cAMP signaling reduces the functionality of Mct1 in cerebrovascular endothelial cells by facilitating its entry into a highly dynamic vesicular trafficking pathway that appears to lead to the transporter's trafficking to autophagosomes and lysosomes.

  8. Neonatal Mortality, Vesicular Lesions and Lameness Associated with Senecavirus A in a U.S. Sow Farm.

    Science.gov (United States)

    Canning, P; Canon, A; Bates, J L; Gerardy, K; Linhares, D C L; Piñeyro, P E; Schwartz, K J; Yoon, K J; Rademacher, C J; Holtkamp, D; Karriker, L

    2016-08-01

    A 300-sow farrow-to-finish swine operation in the United States experienced a sudden and severe increase in mortality in neonatal piglets with high morbidity followed by vesicular lesions on the snout and feet of adult females and males. Affected live piglets were submitted for diagnostic investigation. Samples tested polymerase chain reaction (PCR) negative for foot-and-mouth disease virus, porcine delta coronavirus, porcine epidemic diarrhoea virus, porcine rotavirus types A, B and C, transmissible gastroenteritis virus, and porcine reproductive and respiratory syndrome virus. Senecavirus A (SV-A) formerly known as Seneca Valley virus was detected by real-time reverse-transcription polymerase chain reaction (rRT-PCR) from serum, skin and faeces of piglets and from serum and faeces of sows. SV-A was isolated in cell culture from piglet samples. SV-A VP1 gene region sequencing from piglet tissues was also successful. A biosecurity and disease entry evaluation was conducted and identified potential biosecurity risks factors for the entry of new pathogens into the operation. This is the first case report in the United States associating SV-A with a clinical course of severe but transient neonatal morbidity and mortality followed by vesicular lesions in breeding stock animals. Veterinarians and animal caretakers must remain vigilant for vesicular foreign animal diseases and report suspicious clinical signs and lesions to state animal health authorities for diagnostic testing and further investigation. © 2016 Blackwell Verlag GmbH.

  9. Decreased platelet vesicular monoamine transporter density in children and adolescents with attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Toren, Paz; Rehavi, Moshe; Luski, Anat; Roz, Netta; Laor, Nathaniel; Lask, Michal; Weizman, Abraham

    2005-03-01

    The aim of the present study was to assess vesicular monoamine transporter (VMAT2) density in attention deficit/hyperactivity disorder (ADHD), a disorder involving monoaminergic dysregulation. It was hypothesized that the hypoactivity of monoaminergic neurotransmission related to ADHD could be associated with an under-expression of VMAT2. We assessed high affinity [3H]dihydrotetrabenazine [TBZOH] binding to platelet VMAT2 in untreated male ADHD children and adolescents (n=11) as compared to age-matched controls (n=14), as well as the correlation between VMAT2 density and the severity of ADHD symptoms as measured by the clinician-administered DSM-IV ADHD Scale (DAS) and the parent-administered Abbreviated Conners' Rating Scale (ACPRS). The [3H]TBZOH binding capacity (Bmax) was significantly lower (17%) in the ADHD group as compared to the controls. There was no difference between the two groups in the affinity (Kd value) of [3H]TBZOH to its binding site. An inverse correlation was found between the ADHD symptom scales and the Bmax values. It remains unclear whether the under-expression of platelet VMAT2 in ADHD children is reflective of a parallel change in the brain, and whether it is primary or an epiphenomenon of ADHD.

  10. Ethosomes as novel vesicular carrier: An overview of the principle, preparation and its applications.

    Science.gov (United States)

    Das, Sanjoy Kumar; Chakraborty, Soumalya; Roy, Chhandita; Rajabalaya, Rajan; Mohaimin, Amal Widaad; Khanam, Jasmina; Nanda, Arunabha; David, Sheba R

    2018-01-15

    In the study of lipid vesicular carriers in permeation enhancement of drug molecules across skin after the success story of liposomes, ethosomes are a recent addition. There are a number of published reviews but still, there is a lack of reviews representing various aspects in a systematic way with a detailed description of current research works. This review serves to fill this deficiency along with a special emphasize on its preparation methods and application. Information was collected from previously published literatures which were represented after analysis in terms of various aspects such as principles, composition, preparation, mechanism of penetration, modified forms, characterization, marketed preparation and its application. This review is represented in an informative and easily understandable way. Basic principles and background of exploring were covered in the introduction section. Composition section contains the basic components of formulations along with the impact of various parameters on the characterization of the ethosome. A detailed discussion of all the methods along with their own utility is elaborately discussed. Various aspects of characterization of ethosomes are also discussed. Therapeutic and cosmetic applications of ethosomes are also outlined here. In spite of having a potent permeation enhancing and targeted drug release profile ethosome suffers from limited commercialization. Various challenges regarding its commercialization and product development are also discussed in this review with an objective of acting as a directional route for the researchers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  11. Amyloid-Beta Induced Changes in Vesicular Transport of BDNF in Hippocampal Neurons

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    Bianca Seifert

    2016-01-01

    Full Text Available The neurotrophin brain derived neurotrophic factor (BDNF is an important growth factor in the CNS. Deficits in transport of this secretory protein could underlie neurodegenerative diseases. Investigation of disease-related changes in BDNF transport might provide insights into the cellular mechanism underlying, for example, Alzheimer’s disease (AD. To analyze the role of BDNF transport in AD, live cell imaging of fluorescently labeled BDNF was performed in hippocampal neurons of different AD model systems. BDNF and APP colocalized with low incidence in vesicular structures. Anterograde as well as retrograde transport of BDNF vesicles was reduced and these effects were mediated by factors released from hippocampal neurons into the extracellular medium. Transport of BDNF was altered at a very early time point after onset of human APP expression or after acute amyloid-beta(1-42 treatment, while the activity-dependent release of BDNF remained unaffected. Taken together, extracellular cleavage products of APP induced rapid changes in anterograde and retrograde transport of BDNF-containing vesicles while release of BDNF was unaffected by transgenic expression of mutated APP. These early transport deficits might lead to permanently impaired brain functions in the adult brain.

  12. Endoplasmosis and exoplasmosis: the evolutionary principles underlying endocytosis, exocytosis, and vesicular transport.

    Science.gov (United States)

    Schmid, Johannes A

    2016-05-01

    Eukaryotic cells are characterized by a multicompartmental structure with a variety of organelles. Vesicular transport between these compartments requires membrane fusion events. Based on a membrane topology view, we conclude that there are two basic mechanisms of membrane fusion, namely where the membranes first come in contact with the cis-side (the plasmatic phase of the lipid bilayer) or with the trans-side (the extra-plasmatic face). We propose to designate trans-membrane fusion processes as "endoplasmosis" as they lead to uptake of a compartment into the plasmatic phase. Vice versa we suggest the term "exoplasmosis" (as already suggested in a 1964 publication) for cis-membrane fusion events, where the interior of a vesicle is released to an extraplasmatic environment (the extracellular space or the lumen of a compartment). This concept is supported by the fact that all cis- and all trans-membrane fusions, respectively, exhibit noticeable similarities implying that they evolved from two functionally different mechanisms.

  13. [Antitumor effects of matrix protein of vesicular stomatic virus on EL4 lymphoma mice].

    Science.gov (United States)

    Lin, Shi-jia; Yu, Qin-mei; Meng, Wen-tong; Wen, Yan-jun; Chen, Li-juan; Niu, Ting

    2011-03-01

    To explore antitumor effects of plasmid pcDNA3. 1-MP encoding matrix protein of vesicular stomatitis virus (VSV) complexed with cationic liposome (DOTAP:CHOL) in mice with EL4 lymphoma. C57BL/6 mouse model with EL4 lymphoma was established. Sixty mice bearing EL4 lymphoma were divided randomly into five groups including Lip-MP, Lip-pVAX, Lip, ADM and NS groups, which were intravenously injected with liposome-pcDNA 3. 1-MP complex, liposome-pVAX complex, empty liposome, Adriamycin and normal saline respectively every three days. Tumor volumes and survival time were monitored. Microvessel density and tumor proliferative index in tumor tissues were determined by CD31, Ki-67 immunohistochemistry staining, meanwhile the tumor apoptosis index was measured by TUNEL method. From 6 days after treatments on, the tumor volume in Lip-MP group was much smaller than that in Lip-pVAX, Lip and NS group (P EL4 tumor cells in vivo (P EL4 lymphoma, which may be related to the induction of tumor cell apoptosis, inhibition of tumor angiogenesis, and suppression of tumor cell proliferation.

  14. Structure of the L Protein of Vesicular Stomatitis Virus from Electron Cryomicroscopy.

    Science.gov (United States)

    Liang, Bo; Li, Zongli; Jenni, Simon; Rahmeh, Amal A; Morin, Benjamin M; Grant, Timothy; Grigorieff, Nikolaus; Harrison, Stephen C; Whelan, Sean P J

    2015-07-16

    The large (L) proteins of non-segmented, negative-strand RNA viruses, a group that includes Ebola and rabies viruses, catalyze RNA-dependent RNA polymerization with viral ribonucleoprotein as template, a non-canonical sequence of capping and methylation reactions, and polyadenylation of viral messages. We have determined by electron cryomicroscopy the structure of the vesicular stomatitis virus (VSV) L protein. The density map, at a resolution of 3.8 Å, has led to an atomic model for nearly all of the 2109-residue polypeptide chain, which comprises three enzymatic domains (RNA-dependent RNA polymerase [RdRp], polyribonucleotidyl transferase [PRNTase], and methyltransferase) and two structural domains. The RdRp resembles the corresponding enzymatic regions of dsRNA virus polymerases and influenza virus polymerase. A loop from the PRNTase (capping) domain projects into the catalytic site of the RdRp, where it appears to have the role of a priming loop and to couple product elongation to large-scale conformational changes in L. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Structure of the L-protein of vesicular stomatitis virus from electron cryomicroscopy

    Science.gov (United States)

    Liang, Bo; Li, Zongli; Jenni, Simon; Rahmeh, Amal A.; Morin, Benjamin M.; Grant, Tim; Grigorieff, Nikolaus; Harrison, Stephen C.; Whelan, Sean P.J.

    2015-01-01

    The large (L) proteins of non-segmented, negative-strand RNA viruses, a group that includes Ebola and rabies viruses, catalyze RNA-dependent RNA polymerization with viral ribonucleoprotein as template, a noncanonical sequence of capping and methylation reactions, and polyadenylation of viral messages. We have determined by electron cryomicroscopy the structure of the vesicular stomatitis virus (VSV) L protein. The density map, at a resolution of 3.8 Å, has led to an atomic model for nearly all of the 2109-residue polypeptide chain, which comprises three enzymatic domains [RNA-dependent RNA polymerase (RdRp), polyribonucleotidyl transferase (PRNTase), and methyl transferase] and two structural domains. The RdRp resembles the corresponding enzymatic regions of dsRNA virus polymerases and influenza virus polymerase. A loop from the PRNTase (capping) domain projects into the catalytic site of the RdRp, where it appears to have the role of a priming loop and to couple product elongation to large-scale conformational changes in L. PMID:26144317

  16. Vesicular stomatitis virus as a flexible platform for oncolytic virotherapy against cancer

    Science.gov (United States)

    Hastie, Eric

    2012-01-01

    Oncolytic virus (OV) therapy is an emerging anti-cancer approach that utilizes viruses to preferentially infect and kill cancer cells, while not harming healthy cells. Vesicular stomatitis virus (VSV) is a prototypic non-segmented, negative-strand RNA virus with inherent OV qualities. Antiviral responses induced by type I interferon pathways are believed to be impaired in most cancer cells, making them more susceptible to VSV than normal cells. Several other factors make VSV a promising OV candidate for clinical use, including its well-studied biology, a small, easily manipulated genome, relative independence of a receptor or cell cycle, cytoplasmic replication without risk of host-cell transformation, and lack of pre-existing immunity in humans. Moreover, various VSV-based recombinant viruses have been engineered via reverse genetics to improve oncoselectivity, safety, oncotoxicity and stimulation of tumour-specific immunity. Alternative delivery methods are also being studied to minimize premature immune clearance of VSV. OV treatment as a monotherapy is being explored, although many studies have employed VSV in combination with radiotherapy, chemotherapy or other OVs. Preclinical studies with various cancers have demonstrated that VSV is a promising OV; as a result, a human clinical trial using VSV is currently in progress. PMID:23052398

  17. PEGylation of Vesicular Stomatitis Virus Extends Virus Persistence in Blood Circulation of Passively Immunized Mice

    Science.gov (United States)

    Tesfay, Mulu Z.; Kirk, Amber C.; Hadac, Elizabeth M.; Griesmann, Guy E.; Federspiel, Mark J.; Barber, Glen N.; Henry, Stephen M.; Peng, Kah-Whye

    2013-01-01

    We are developing oncolytic vesicular stomatitis viruses (VSVs) for systemic treatment of multiple myeloma, an incurable malignancy of antibody-secreting plasma cells that are specifically localized in the bone marrow. One of the presumed advantages for using VSV as an oncolytic virus is that human infections are rare and preexisting anti-VSV immunity is typically lacking in cancer patients, which is very important for clinical success. However, our studies show that nonimmune human and mouse serum can neutralize clinical-grade VSV, reducing the titer by up to 4 log units in 60 min. In addition, we show that neutralizing anti-VSV antibodies negate the antitumor efficacy of VSV, a concern for repeat VSV administration. We have investigated the potential use of covalent modification of VSV with polyethylene glycol (PEG) or a function-spacer-lipid (FSL)–PEG construct to inhibit serum neutralization and to limit hepatosplenic sequestration of systemically delivered VSV. We report that in mice passively immunized with neutralizing anti-VSV antibodies, PEGylation of VSV improved the persistence of VSV in the blood circulation, maintaining a more than 1-log-unit increase in VSV genome copies for up to 1 h compared to the genome copy numbers for the non-PEGylated virus, which was mostly cleared within 10 min after intravenous injection. We are currently investigating if this increase in PEGylated VSV circulating half-life can translate to increased virus delivery and better efficacy in mouse models of multiple myeloma. PMID:23325695

  18. Vesicular stomatitis virus infection promotes immune evasion by preventing NKG2D-ligand surface expression.

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    Helle Jensen

    Full Text Available Vesicular stomatitis virus (VSV has recently gained attention for its oncolytic ability in cancer treatment. Initially, we hypothesized that VSV infection could increase immune recognition of cancer cells through induction of the immune stimulatory NKG2D-ligands. Here we show that VSV infection leads to a robust induction of MICA mRNA expression, however the subsequent surface expression is potently hindered. Thus, VSV lines up with human cytomegalovirus (HCMV and adenovirus, which actively subvert the immune system by negatively affecting NKG2D-ligand surface expression. VSV infection caused an active suppression of NKG2D-ligand surface expression, affecting both endogenous and histone deacetylase (HDAC-inhibitor induced MICA, MICB and ULBP-2 expression. The classical immune escape mechanism of VSV (i.e., the M protein blockade of nucleocytoplasmic mRNA transport was not involved, as the VSV mutant strain, VSV(ΔM51, which possess a defective M protein, prevented MICA surface expression similarly to wild-type VSV. The VSV mediated down modulation of NKG2D-ligand expression did not involve apoptosis. Constitutive expression of MICA bypassed the escape mechanism, suggesting that VSV affect NKG2D-ligand expression at an early post-transcriptional level. Our results show that VSV possess an escape mechanism, which could affect the immune recognition of VSV infected cancer cells. This may also have implications for immune recognition of cancer cells after combined treatment with VSV and chemotherapeutic drugs.

  19. Vesicular stomatitis virus polymerase's strong affinity to its template suggests exotic transcription models.

    Directory of Open Access Journals (Sweden)

    Xiaolin Tang

    2014-12-01

    Full Text Available Vesicular stomatitis virus (VSV is the prototype for negative sense non segmented (NNS RNA viruses which include potent human and animal pathogens such as Rabies, Ebola and measles. The polymerases of NNS RNA viruses only initiate transcription at or near the 3' end of their genome template. We measured the dissociation constant of VSV polymerases from their whole genome template to be 20 pM. Given this low dissociation constant, initiation and sustainability of transcription becomes nontrivial. To explore possible mechanisms, we simulated the first hour of transcription using Monte Carlo methods and show that a one-time initial dissociation of all polymerases during entry is not sufficient to sustain transcription. We further show that efficient transcription requires a sliding mechanism for non-transcribing polymerases and can be realized with different polymerase-polymerase interactions and distinct template topologies. In conclusion, we highlight a model in which collisions between transcribing and sliding non-transcribing polymerases result in release of the non-transcribing polymerases allowing for redistribution of polymerases between separate templates during transcription and suggest specific experiments to further test these mechanisms.

  20. Inducible vesicular stomatitis virus (VSV) L cell line for packaging of recombinant VSV.

    Science.gov (United States)

    Hong, Seong-Karp; Jung, Yong-Tae; Park, Seung-Won; Paik, Soon-Young

    2005-10-01

    Recently, recombinant vesicular stomatitis viruses (VSV) have been developed as high-level expression vectors which serve as effective vaccine vectors in animals. An ideal approach for VSV vector production would be the development of stable packaging cell lines that can produce vector particles without transfection step. In this report, we describe generation of an inducible cell line that expresses the VSV polymerase gene (L) under the control of the reverse tetracycline-controlled transactivator (rtTA) system as a first step to make VSV-based packaging cell lines. Integrated polymerase (L) gene was controlled by an rtetR-dependent promoter in the rtTA-producing BHK cell line. When the cell lines were cultured in the presence of tet (tetracycline) or tetracycline derivative doxycycline, the recombinant VSV and wild type VSV were replicated, whereas in the absence of tet or tetracycline derivative doxycycline, the recombinant VSV was not replicated. Viral supernatants were harvested, diluted, and monitored by plaque assay for the presence of infectious VSV. Plaques of VSV containing an additional sequence encoding the EGFP protein allowed rapid detection of infection. Our results suggest wide applications of other surrogate viruses based on VSV. The availability of stable packaging cell lines represents a step toward the use of a VSV vector delivery system that can allow scale-up production of vector-stocks for gene therapy.

  1. [Vesicular stomatitis virus (VSV) as a vaccine vector for immunization against viral infections].

    Science.gov (United States)

    Tomczyk, Tomasz; Orzechowska, Beata

    2013-01-11

    Vesicular stomatitis virus (VSV), a member of the Rhabdoviridae family, is a promising candidate for potential use in construction of antiviral vaccines. In the natural environment VSV is a pathogen of wild ungulates and livestock. Some of the features that make VSV an excellent platform for the development of a range of viral therapeutics includes its immunogenicity and ability to grow to high titers in cell lines approved for vaccine use. Infection in humans is rare and usually asymptomatic, with mild flu-like symptoms. Moreover, due to affinity of VSV envelope glycoprotein to the LDL (low-density lipoprotein) receptor, VSV is effective at targeting a variety of tissues in vivo. A series of research results confirm the possibility of developing VSV-based vaccines against human papilloma viruses (HPV), human immunodeficiency virus (HIV), hepatitis B virus (HBV) and filoviruses (MARV, ZEBOV and SEBOV), as well as the potential use of a successfully developed vaccine against hepatitis C virus (HCV). VSV is neurotropic and infection can cause a viral encephalitis in experimental animals. Therefore, intensive studies are being undertaken to achieve satisfactory expression of the viral antigens while maintaining the safety of the constructed vectors.

  2. Oncolytic vesicular stomatitis virus expressing interferon-σ has enhanced therapeutic activity

    Directory of Open Access Journals (Sweden)

    Marie-Claude Bourgeois-Daigneault

    2016-01-01

    Full Text Available Oncolytic viruses are known to stimulate the antitumor immune response by specifically replicating in tumor cells. This is believed to be an important aspect of the durable responses observed in some patients and the field is rapidly moving toward immunotherapy. As a further means to engage the immune system, we engineered a virus, vesicular stomatitis virus (VSV, to encode the proinflammatory cytokine interferon-σ. We used the 4T1 mammary adenocarcinoma as well as other murine tumor models to characterize immune responses in tumor-bearing animals generated by treatment with our viruses. The interferon-σ-encoding virus demonstrated greater activation of dendritic cells and drove a more profound secretion of proinflammatory cytokines compared to the parental virus. From a therapeutic point of view, the interferon-σ virus slowed tumor growth, minimized lung tumors, and prolonged survival in several murine tumor models. The improved efficacy was lost in immunocompromized animals; hence the mechanism appears to be T-cell-mediated. Taken together, these results demonstrate the ability of oncolytic viruses to act as immune stimulators to drive antitumor immunity as well as their potential for targeted gene therapy.

  3. Different effect of proteasome inhibition on vesicular stomatitis virus and poliovirus replication.

    Directory of Open Access Journals (Sweden)

    Nickolay Neznanov

    2008-04-01

    Full Text Available Proteasome activity is an important part of viral replication. In this study, we examined the effect of proteasome inhibitors on the replication of vesicular stomatitis virus (VSV and poliovirus. We found that the proteasome inhibitors significantly suppressed VSV protein synthesis, virus accumulation, and protected infected cells from toxic effect of VSV replication. In contrast, poliovirus replication was delayed, but not diminished in the presence of the proteasome inhibitors MG132 and Bortezomib. We also found that inhibition of proteasomes stimulated stress-related processes, such as accumulation of chaperone hsp70, phosphorylation of eIF2alpha, and overall inhibition of translation. VSV replication was sensitive to this stress with significant decline in replication process. Poliovirus growth was less sensitive with only delay in replication. Inhibition of proteasome activity suppressed cellular and VSV protein synthesis, but did not reduce poliovirus protein synthesis. Protein kinase GCN2 supported the ability of proteasome inhibitors to attenuate general translation and to suppress VSV replication. We propose that different mechanisms of translational initiation by VSV and poliovirus determine their sensitivity to stress induced by the inhibition of proteasomes. To our knowledge, this is the first study that connects the effect of stress induced by proteasome inhibition with the efficiency of viral infection.

  4. Vesicular Stomatitis Virus Variants Selectively Infect and Kill Human Melanomas but Not Normal Melanocytes

    Science.gov (United States)

    Wollmann, Guido; Davis, John N.; Bosenberg, Marcus W.

    2013-01-01

    Metastatic malignant melanoma remains one of the most therapeutically challenging forms of cancer. Here we test replication-competent vesicular stomatitis viruses (VSV) on 19 primary human melanoma samples and compare these infections with those of normal human melanocyte control cells. Even at a low viral concentration, we found a strong susceptibility to viral oncolysis in over 70% of melanomas. In contrast, melanocytes displayed strong resistance to virus infection and showed complete protection by interferon. Several recombinant VSVs were compared, and all infected and killed most melanomas with differences in the time course with increasing rates of melanoma infection, as follows: VSV-CT9-M51 VSV-M51 VSV-G/GFP VSV-rp30. VSV-rp30 sequencing revealed 2 nonsynonymous mutations at codon positions P126 and L223, both of which appear to be required for the enhanced phenotype. VSV-rp30 showed effective targeting and infection of multiple subcutaneous and intracranial melanoma xenografts in SCID mice after tail vein virus application. Sequence analysis of mutations in the melanomas used revealed that BRAF but not NRAS gene mutation status was predictive for enhanced susceptibility to infection. In mouse melanoma models with specific induced gene mutations including mutations of the Braf, Pten, and Cdkn2a genes, viral infection correlated with the extent of malignant transformation. Similar to human melanocytes, mouse melanocytes resisted VSV-rp30 infection. This study confirms the general susceptibility of the majority of human melanoma types for VSV-mediated oncolysis. PMID:23552414

  5. Vesicular stomatitis virus as an oncolytic agent against pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Murphy, Andrea M; Besmer, Dahlia M; Moerdyk-Schauwecker, Megan; Moestl, Natascha; Ornelles, David A; Mukherjee, Pinku; Grdzelishvili, Valery Z

    2012-03-01

    Vesicular stomatitis virus (VSV) is a promising oncolytic agent against a variety of cancers. However, it has never been tested in any pancreatic cancer model. Pancreatic ductal adenocarcinoma (PDA) is the most common and aggressive form of pancreatic cancer. In this study, the oncolytic potentials of several VSV variants were analyzed in a panel of 13 clinically relevant human PDA cell lines and compared to conditionally replicative adenoviruses (CRAds), Sendai virus and respiratory syncytial virus. VSV variants showed oncolytic abilities superior to those of other viruses, and some cell lines that exhibited resistance to other viruses were successfully killed by VSV. However, PDA cells were highly heterogeneous in their susceptibility to virus-induced oncolysis, and several cell lines were resistant to all tested viruses. Resistant cells showed low levels of very early VSV RNA synthesis, indicating possible defects at initial stages of infection. In addition, unlike permissive PDA cell lines, most of the resistant cell lines were able to both produce and respond to interferon, suggesting that intact type I interferon responses contributed to their resistance phenotype. Four cell lines that varied in their permissiveness to VSV-ΔM51 and CRAd dl1520 were tested in mice, and the in vivo results closely mimicked those in vitro. While our results demonstrate that VSV is a promising oncolytic agent against PDA, further studies are needed to better understand the molecular mechanisms of resistance of some PDAs to oncolytic virotherapy.

  6. Repeatable population dynamics among vesicular stomatitis virus lineages evolved under high co-infection

    Directory of Open Access Journals (Sweden)

    Elizabeth S.C.P. Williams

    2016-03-01

    Full Text Available Parasites and hosts can experience oscillatory cycles, where the densities of these interacting species dynamically fluctuate through time. Viruses with different replication strategies can also interact to produce cyclical dynamics. Frequent cellular co-infection can select for defective-interfering particles (DIPs: cheater viruses with shortened genomes that interfere with intracellular replication of full-length (ordinary viruses. DIPs are positively selected when rare because they out-replicate ordinary viruses during co-infection, but DIPs are negatively selected when common because ordinary viruses become unavailable for intracellular exploitation via cheating. Here we tested whether oscillatory dynamics of ordinary viruses were similar across independently evolved populations of vesicular stomatitis virus (VSV. Results showed identical cyclical dynamics across populations in the first 10 experimental passages, which transitioned to repeatable dampened oscillations by passage 20. Genomic analyses revealed parallel molecular substitutions across populations, particularly novel mutations that became dominant by passage 10. Our study showed that oscillatory dynamics and molecular evolution of interacting viruses were highly repeatable in VSV populations passaged under frequent co-infection. Furthermore, our data suggested that frequent co-infection with DIPs caused lowered performance of full-length viruses, by reducing their population densities by orders of magnitude compared to reproduction of ordinary viruses during strictly clonal infections.

  7. Vesicular stomatitis virus variants selectively infect and kill human melanomas but not normal melanocytes.

    Science.gov (United States)

    Wollmann, Guido; Davis, John N; Bosenberg, Marcus W; van den Pol, Anthony N

    2013-06-01

    Metastatic malignant melanoma remains one of the most therapeutically challenging forms of cancer. Here we test replication-competent vesicular stomatitis viruses (VSV) on 19 primary human melanoma samples and compare these infections with those of normal human melanocyte control cells. Even at a low viral concentration, we found a strong susceptibility to viral oncolysis in over 70% of melanomas. In contrast, melanocytes displayed strong resistance to virus infection and showed complete protection by interferon. Several recombinant VSVs were compared, and all infected and killed most melanomas with differences in the time course with increasing rates of melanoma infection, as follows: VSV-CT9-M51 VSV-M51 VSV-G/GFP VSV-rp30. VSV-rp30 sequencing revealed 2 nonsynonymous mutations at codon positions P126 and L223, both of which appear to be required for the enhanced phenotype. VSV-rp30 showed effective targeting and infection of multiple subcutaneous and intracranial melanoma xenografts in SCID mice after tail vein virus application. Sequence analysis of mutations in the melanomas used revealed that BRAF but not NRAS gene mutation status was predictive for enhanced susceptibility to infection. In mouse melanoma models with specific induced gene mutations including mutations of the Braf, Pten, and Cdkn2a genes, viral infection correlated with the extent of malignant transformation. Similar to human melanocytes, mouse melanocytes resisted VSV-rp30 infection. This study confirms the general susceptibility of the majority of human melanoma types for VSV-mediated oncolysis.

  8. Preimplantation bovine embryos: Pathobiology of Haemophilus somnus exposure and resistance mechanisms to vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, M.S.

    1988-01-01

    Preimplantation bovine embryos were exposed in vitro to H. somnus to determine if the bacteria would adhere to zona pellucida-intact (ZP-I) embryos or adhere to or infect ZP-free embryos. The effect of H. somnus on embryonic development in vitro was also investigated. Electrophoretic comparisons of outer membrane proteins of H. somnus revealed 2 major protein bands common to 10 H. somnus isolates. A monoclonal antibody produced against the outer membrane proteins reacted to one of the major protein bands. The sensitivity of a nucleic acid probe for detection of vesicular stomatitis virus (VSV) was validated in cells in culture and used to determine if the synthetic double-stranded complex of polyriboinosinic and polyribocytidylic acids (poly I:C) would induce viral resistance in cultured bovine embryos. Two {sup 32}P-nick translated probes of high specific activity prepared from plasmids containing nucleic acid sequences of VSV virus were employed for viral mRNA detection in the tissue culture cells using a DNA-hybridization dot-blot technique. Using one of the probes, the technique was applied to detect differences in viral replication between four groups of bovine embryos (nonexposed, exposed to VSV virus, poly I:C-treated, and poly I:C-treated and exposed to VSV). The nucleic acid probe was sufficiently sensitive to detect differences in quantities of VSV mRNA among embryo treatment groups, resulting in the demonstration that resistance to viral infection was induced in day 9 bovine embryos.

  9. Recent advances in vesicular stomatitis virus-based oncolytic virotherapy: a 5-year update.

    Science.gov (United States)

    Felt, Sébastien A; Grdzelishvili, Valery Z

    2017-11-16

    Oncolytic virus (OV) therapy is an anti-cancer approach that uses viruses that preferentially infect, replicate in and kill cancer cells. Vesicular stomatitis virus (VSV, a rhabdovirus) is an OV that is currently being tested in the USA in several phase I clinical trials against different malignancies. Several factors make VSV a promising OV: lack of pre-existing human immunity against VSV, a small and easy to manipulate genome, cytoplasmic replication without risk of host cell transformation, independence of cell cycle and rapid growth to high titres in a broad range of cell lines facilitating large-scale virus production. While significant advances have been made in VSV-based OV therapy, room for improvement remains. Here we review recent studies (published in the last 5 years) that address 'old' and 'new' challenges of VSV-based OV therapy. These studies focused on improving VSV safety, oncoselectivity and oncotoxicity; breaking resistance of some cancers to VSV; preventing premature clearance of VSV; and stimulating tumour-specific immunity. Many of these approaches were based on combining VSV with other therapeutics. This review also discusses another rhabdovirus closely related to VSV, Maraba virus, which is currently being tested in Canada in phase I/II clinical trials.

  10. Genetic Inactivation of COPI Coatomer Separately Inhibits Vesicular Stomatitis Virus Entry and Gene Expression

    Science.gov (United States)

    Burdeinick-Kerr, Rebeca

    2012-01-01

    Viruses coopt cellular membrane transport to invade cells, establish intracellular sites of replication, and release progeny virions. Recent genome-wide RNA interference (RNAi) screens revealed that genetically divergent viruses require biosynthetic membrane transport by the COPI coatomer complex for efficient replication. Here we found that disrupting COPI function by RNAi inhibited an early stage of vesicular stomatitis virus (VSV) replication. To dissect which replication stage(s) was affected by coatomer inactivation, we used visual and biochemical assays to independently measure the efficiency of viral entry and gene expression in hamster (ldlF) cells depleted of the temperature-sensitive ε-COP subunit. We show that ε-COP depletion for 12 h caused a primary block to virus internalization and a secondary defect in viral gene expression. Using brefeldin A (BFA), a chemical inhibitor of COPI function, we demonstrate that short-term (1-h) BFA treatments inhibit VSV gene expression, while only long-term (12-h) treatments block virus entry. We conclude that prolonged coatomer inactivation perturbs cellular endocytic transport and thereby indirectly impairs VSV entry. Our results offer an explanation of why COPI coatomer is frequently identified in screens for cellular factors that support cell invasion by microbial pathogens. PMID:22072764

  11. Vesicular stomatitis virus enables gene transfer and transsynaptic tracing in a wide range of organisms

    Science.gov (United States)

    Mundell, Nathan A.; Beier, Kevin T.; Pan, Y. Albert; Lapan, Sylvain W.; Göz Aytürk, Didem; Berezovskii, Vladimir K.; Wark, Abigail R.; Drokhlyansky, Eugene; Bielecki, Jan; Born, Richard T.; Schier, Alexander F.

    2015-01-01

    Current limitations in technology have prevented an extensive analysis of the connections among neurons, particularly within nonmammalian organisms. We developed a transsynaptic viral tracer originally for use in mice, and then tested its utility in a broader range of organisms. By engineering the vesicular stomatitis virus (VSV) to encode a fluorophore and either the rabies virus glycoprotein (RABV‐G) or its own glycoprotein (VSV‐G), we created viruses that can transsynaptically label neuronal circuits in either the retrograde or anterograde direction, respectively. The vectors were investigated for their utility as polysynaptic tracers of chicken and zebrafish visual pathways. They showed patterns of connectivity consistent with previously characterized visual system connections, and revealed several potentially novel connections. Further, these vectors were shown to infect neurons in several other vertebrates, including Old and New World monkeys, seahorses, axolotls, and Xenopus. They were also shown to infect two invertebrates, Drosophila melanogaster, and the box jellyfish, Tripedalia cystophora, a species previously intractable for gene transfer, although no clear evidence of transsynaptic spread was observed in these species. These vectors provide a starting point for transsynaptic tracing in most vertebrates, and are also excellent candidates for gene transfer in organisms that have been refractory to other methods. J. Comp. Neurol. 523:1639–1663, 2015. © 2015 Wiley Periodicals, Inc. PMID:25688551

  12. Induction of apoptosis in pancreatic cancer cells by vesicular stomatitis virus.

    Science.gov (United States)

    Felt, Sébastien A; Moerdyk-Schauwecker, Megan J; Grdzelishvili, Valery Z

    2015-01-01

    Effective oncolytic virus (OV) therapy is dependent on the ability of replication-competent viruses to kill infected cancer cells. We previously showed that human pancreatic ductal adenocarcinoma (PDAC) cell lines are highly heterogeneous in their permissiveness to vesicular stomatitis virus (VSV), in part due to differences in type I interferon (IFN) signaling. Here, using 10 human PDAC cell lines and three different VSV recombinants (expressing ΔM51 or wild type matrix protein), we examined cellular and viral factors affecting VSV-mediated apoptosis activation in PDACs. In most cell lines, VSVs activated both extrinsic and intrinsic apoptosis pathways, and VSV-ΔM51 primarily activated the type II extrinsic pathway. In cells with defective IFN signaling, all VSV recombinants induced robust apoptosis, whereas VSV-ΔM51 was a more effective apoptosis activator in PDACs with virus-inducible IFN signaling. Three cell lines constitutively expressing high levels of IFN-stimulated genes (ISGs) were resistant to apoptosis under most experimental conditions, even when VSV replication levels were dramatically increased by Jak inhibitor I treatment. Two of these cell lines also poorly activated apoptosis when treated with Fas activating antibody, suggesting a general defect in apoptosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Durability of a vesicular stomatitis virus-based marburg virus vaccine in nonhuman primates.

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    Chad E Mire

    Full Text Available The filoviruses, Marburg virus (MARV and Ebola virus, causes severe hemorrhagic fever with high mortality in humans and nonhuman primates. A promising filovirus vaccine under development is based on a recombinant vesicular stomatitis virus (rVSV that expresses individual filovirus glycoproteins (GPs in place of the VSV glycoprotein (G. These vaccines have shown 100% efficacy against filovirus infection in nonhuman primates when challenge occurs 28-35 days after a single injection immunization. Here, we examined the ability of a rVSV MARV-GP vaccine to provide protection when challenge occurs more than a year after vaccination. Cynomolgus macaques were immunized with rVSV-MARV-GP and challenged with MARV approximately 14 months after vaccination. Immunization resulted in the vaccine cohort of six animals having anti-MARV GP IgG throughout the pre-challenge period. Following MARV challenge none of the vaccinated animals showed any signs of clinical disease or viremia and all were completely protected from MARV infection. Two unvaccinated control animals exhibited signs consistent with MARV infection and both succumbed. Importantly, these data are the first to show 100% protective efficacy against any high dose filovirus challenge beyond 8 weeks after final vaccination. These findings demonstrate the durability of VSV-based filovirus vaccines.

  14. Triptolide-mediated inhibition of interferon signaling enhances vesicular stomatitis virus-based oncolysis.

    Science.gov (United States)

    Ben Yebdri, Fethia; Van Grevenynghe, Julien; Tang, Vera A; Goulet, Marie-Line; Wu, Jian Hui; Stojdl, David F; Hiscott, John; Lin, Rongtuan

    2013-11-01

    Preclinical and clinical trials demonstrated that use of oncolytic viruses (OVs) is a promising new therapeutic approach to treat multiple types of cancer. To further improve their viral oncolysis, experimental strategies are now combining OVs with different cytotoxic compounds. In this study, we investigated the capacity of triptolide - a natural anticancer molecule - to enhance vesicular stomatitis virus (VSV) oncolysis in OV-resistant cancer cells. Triptolide treatment increased VSV replication in the human prostate cancer cell line PC3 and in other VSV-resistant cells in a dose- and time-dependent manner in vitro and in vivo. Mechanistically, triptolide (TPL) inhibited the innate antiviral response by blocking type I interferon (IFN) signaling, downstream of IRF3 activation. Furthermore, triptolide-enhanced VSV-induced apoptosis in a dose-dependent fashion in VSV-resistant cells, as measured by annexin-V, cleaved caspase-3, and B-cell lymphoma 2 staining. In vivo, using the TSA mammary adenocarcinoma and PC3 mouse xenograft models, combination treatment with VSV and triptolide delayed tumor growth and prolonged survival of tumor-bearing animals by enhancing viral replication. Together, these results demonstrate that triptolide inhibition of IFN production sensitizes prostate cancer cells to VSV replication and virus-mediated apoptosis.

  15. Emulating proton-induced conformational changes in the vesicular monoamine transporter VMAT2 by mutagenesis.

    Science.gov (United States)

    Yaffe, Dana; Vergara-Jaque, Ariela; Forrest, Lucy R; Schuldiner, Shimon

    2016-11-22

    Neurotransporters located in synaptic vesicles are essential for communication between nerve cells in a process mediated by neurotransmitters. Vesicular monoamine transporter (VMAT), a member of the largest superfamily of transporters, mediates transport of monoamines to synaptic vesicles and storage organelles in a process that involves exchange of two H(+) per substrate. VMAT transport is inhibited by the competitive inhibitor reserpine, a second-line agent to treat hypertension, and by the noncompetitive inhibitor tetrabenazine, presently in use for symptomatic treatment of hyperkinetic disorders. During the transport cycle, VMAT is expected to occupy at least three different conformations: cytoplasm-facing, occluded, and lumen-facing. The lumen- to cytoplasm-facing transition, facilitated by protonation of at least one of the essential membrane-embedded carboxyls, generates a binding site for reserpine. Here we have identified residues in the cytoplasmic gate and show that mutations that disrupt the interactions in this gate also shift the equilibrium toward the cytoplasm-facing conformation, emulating the effect of protonation. These experiments provide significant insight into the role of proton translocation in the conformational dynamics of a mammalian H(+)-coupled antiporter, and also identify key aspects of the mode of action and binding of two potent inhibitors of VMAT2: reserpine binds the cytoplasm-facing conformation, and tetrabenazine binds the lumen-facing conformation.

  16. Tubular-vesicular transformation in the contractile vacuole system of Dictyostelium.

    Science.gov (United States)

    Gerisch, Günther; Heuser, John; Clarke, Margaret

    2002-01-01

    The contractile vacuole complex of Dictyostelium is the paradigm of a membrane system that undergoes tubular-vesicular transitions during its regular cycle of activities. This system acts as an osmoregulatory organelle in freshwater amoebae and protozoa. It collects fluid in a network of tubules and cisternae, and pumps it out of the cell through transient pores in the plasma membrane. Tubules and vacuoles are interconvertible. The tubular channels are associated with the cortical actin network and are capable of moving and fusing. The contractile vacuole complex is separate from vesicles of the endosomal pathway and preserves its identity in a dispersed state during cell division. We outline techniques to visualize the contractile vacuole system by electron and light microscopy. Emphasis is placed on GFP-fusion proteins that allow visualization of the dynamics of the contractile vacuole network in living cells. Proteins that control activities of this specialized organelle in Dictyostelium have been conserved during evolution and also regulate membrane trafficking in man.

  17. Spatial transmission of Swine Vesicular Disease virus in the 2006-2007 epidemic in Lombardy.

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    Claudia Nassuato

    Full Text Available In 2006 and 2007 pig farming in the region of Lombardy, in the north of Italy, was struck by an epidemic of Swine Vesicular Disease virus (SVDV. In fact this epidemic could be viewed as consisting of two sub-epidemics, as the reported outbreaks occurred in two separate time periods. These periods differed in terms of the provinces or municipalities that were affected and also in terms of the timing of implementation of movement restrictions. Here we use a simple mathematical model to analyse the epidemic data, quantifying between-farm transmission probability as a function of between-farm distance. The results show that the distance dependence of between-farm transmission differs between the two periods. In the first period transmission over relatively long distances occurred with higher probability than in the second period, reflecting the effect of movement restrictions in the second period. In the second period however, more intensive transmission occurred over relatively short distances. Our model analysis explains this in terms of the relatively high density of pig farms in the area most affected in this period, which exceeds a critical farm density for between-farm transmission. This latter result supports the rationale for the additional control measure taken in 2007 of pre-emptively culling farms in that area.

  18. Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks

    Energy Technology Data Exchange (ETDEWEB)

    Hullinger, P

    2008-01-28

    development and subsequent rupturing of vesicles at the coronary band and in the oral cavity. Vesicles and ulcerations can also occur on the mammary gland. Recovery in adult animals usually occurs in 8-15 days. Clinical signs for most serotypes are less dramatic in sheep and goats. Swine can develop very severe coronary band lesions and high mortality in piglets has been observed. One of the challenges of diagnosing FMD is that it may be clinically similar to several other vesicular or ulcerative diseases. FMD is clinically indistinguishable from Vesicular stomatitis, Swine vesicular disease and Vesicular exanthema of swine. It may also resemble Bovine viral diarrhea, Mucosal disease, Infectious bovine rhinotracheitis, Bluetongue, Bovine papular stomatitis, Bovine mammillitis and Rinderpest.

  19. N-Myc expression enhances the oncolytic effects of vesicular stomatitis virus in human neuroblastoma cells

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    Juan C Corredor

    2016-01-01

    Full Text Available N-myc oncogene amplification is associated but not present in all cases of high-risk neuroblastoma (NB. Since oncogene expression could often modulate sensitivity to oncolytic viruses, we wanted to examine if N-myc expression status would determine virotherapy efficacy to high-risk NB. We showed that induction of exogenous N-myc in a non-N-myc-amplified cell line background (TET-21N increased susceptibility to oncolytic vesicular stomatitis virus (mutant VSVδM51 and alleviated the type I IFN-induced antiviral state. Cells with basal N-myc, on the other hand, were less susceptible to virus-induced oncolysis and established a robust IFN-mediated antiviral state. The same effects were also observed in NB cell lines with and without N-myc amplification. Microarray analysis showed that N-myc overexpression in TET-21N cells downregulated IFN-stimulated genes (ISGs with known antiviral functions. Furthermore, virus infection caused significant changes in global gene expression in TET-21N cells overexpressing N-myc. Such changes involved ISGs with various functions. Therefore, the present study showed that augmented susceptibility to VSVδM51 by N-myc at least involves downregulation of ISGs with antiviral functions and alleviation of the IFN-stimulated antiviral state. Our studies suggest the potential utility of N-myc amplification/overexpression as a predictive biomarker of virotherapy response for high-risk NB using IFN-sensitive oncolytic viruses.

  20. Arbuscules of vesicular-arbuscular mycorrhizal fungi inhabit an acidic compartment within plant roots.

    Science.gov (United States)

    Guttenberger, M

    2000-08-01

    The most widespread type of mycorrhiza is the so-called vesicular-arbuscular mycorrhiza. In this endomycorrhiza, fungal hyphae penetrate plant cell walls in the root cortex. There they form densely branched arbuscules. Fungus and plant plasma membrane are separated by a common interfacial apoplast. The pH of the compartment between the symbionts is of pivotal importance for nutrient transfer. Histochemical experiments were conducted to check for an acidic nature of the interface in the model system Glomus versiforme (Karst.) Berch-Allium porrum L. Two chemically different acidotropic dyes (neutral red and LysoSensor Green DND-189) stained the arbuscules intensely. The staining of arbuscules could be eliminated by addition of the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP) or treatments leading to membrane rupture. Therefore, the staining of the arbuscules was based on the ion-trap mechanism, which indicates acidic, membrane-bound compartments. Microscopic examination of stained arbuscules at high optical resolution revealed a peripheral accumulation of the dye. Since plasmolysis rapidly destained the arbuscules, it is concluded that the dyes accumulate in the arbuscular interface, indicating the highly acidic nature of this compartment. The findings are discussed with respect to their relevance for the nutrient transfer in mycorrhizas. In addition, evidence for a discontinuity in the arbuscular interface between the stem and the branches of the arbuscule is given.

  1. Ethosomes of Phenylethyl Resorcinol as Vesicular Delivery System for Skin Lightening Applications

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    Tunyaluk Limsuwan

    2017-01-01

    Full Text Available Ethosome formulations containing phenylethyl resorcinol (PR were developed. The formulation was produced from 0.5% w/v PR, 0.5% w/v cholesterol from lanolin, 3% w/v L-α-phosphatidylcholine from soybean, 30% v/v absolute ethanol, and water up to 100% v/v. It was characterized by a vesicular size of 389 nm, low polydispersity index of 0.266, zeta potential of −34.19±0.44 mV, high PR entrapment efficiency of 71%, and good stability on storage at 4 and 30°C at 75% RH for 4 months. In vitro studies using pig skin revealed that permeation coefficient of PR from ethosomes was significantly higher than that from liposomes. In vitro retention profiles showed that PR accumulation in pig skin following application of ethosome formulations was 7.4-, 3.3-, and 1.8-fold higher than that achieved using liposomes, 20% propylene glycol solution, and 30% hydroethanolic solution, respectively. An inhibition value of around 80% was measured for antityrosinase activity of PR in pig skin. Consistently, ethosomes exhibited higher tyrosinase inhibition activity and melanin content reduction when compared to other formulations in B16 melanoma cells. Ethosomes did not cause acute dermal irritation in albino rabbits. These findings demonstrate that ethosomes are capable of delivering PR into the skin efficiently and hold promise for topical application of skin lightening products.

  2. Ethosomes of Phenylethyl Resorcinol as Vesicular Delivery System for Skin Lightening Applications.

    Science.gov (United States)

    Limsuwan, Tunyaluk; Boonme, Prapaporn; Khongkow, Pasarat; Amnuaikit, Thanaporn

    2017-01-01

    Ethosome formulations containing phenylethyl resorcinol (PR) were developed. The formulation was produced from 0.5% w/v PR, 0.5% w/v cholesterol from lanolin, 3% w/v L-α-phosphatidylcholine from soybean, 30% v/v absolute ethanol, and water up to 100% v/v. It was characterized by a vesicular size of 389 nm, low polydispersity index of 0.266, zeta potential of -34.19 ± 0.44 mV, high PR entrapment efficiency of 71%, and good stability on storage at 4 and 30°C at 75% RH for 4 months. In vitro studies using pig skin revealed that permeation coefficient of PR from ethosomes was significantly higher than that from liposomes. In vitro retention profiles showed that PR accumulation in pig skin following application of ethosome formulations was 7.4-, 3.3-, and 1.8-fold higher than that achieved using liposomes, 20% propylene glycol solution, and 30% hydroethanolic solution, respectively. An inhibition value of around 80% was measured for antityrosinase activity of PR in pig skin. Consistently, ethosomes exhibited higher tyrosinase inhibition activity and melanin content reduction when compared to other formulations in B16 melanoma cells. Ethosomes did not cause acute dermal irritation in albino rabbits. These findings demonstrate that ethosomes are capable of delivering PR into the skin efficiently and hold promise for topical application of skin lightening products.

  3. Ethosomes - novel vesicular carriers for enhanced delivery: characterization and skin penetration properties.

    Science.gov (United States)

    Touitou, E; Dayan, N; Bergelson, L; Godin, B; Eliaz, M

    2000-04-03

    This work describes a novel carrier for enhanced skin delivery, the ethosomal system, which is composed of phospholipid, ethanol and water. Ethosomal systems were much more efficient at delivering a fluorescent probe to the skin in terms of quantity and depth, than either liposomes or hydroalcoholic solution. The ethosomal system dramatically enhanced the skin permeation of minoxidil in vitro compared with either ethanolic or hydroethanolic solution or phospholipid ethanolic micellar solution of minoxidil. In addition, the transdermal delivery of testosterone from an ethosomal patch was greater both in vitro and in vivo than from commercially available patches. Skin permeation of ethosomal components, ethanol and phospholipid, was demonstrated in diffusion-cell experiments. Ethosomal systems composed of soy phosphatidylcholine 2%, ethanol 30% and water were shown by electron microscopy to contain multilamellar vesicles. 31P-NMR studies confirmed the bilayer configuration of the lipids. Calorimetry and fluorescence measurements suggested that the vesicular bilayers are flexible, having a relatively low T(m) and fluorescence anisotropy compared with liposomes obtained in the absence of ethanol. Dynamic light scattering measurements indicated that ethanol imparted a negative charge to the vesicles. The average vesicle size, as measured by dynamic light scattering, was modulated by altering the ethosome composition. Experiments using fluorescent probes and ultracentrifugation showed that the ethosomes had a high entrapment capacity for molecules of various lyophilicities.

  4. Reconstruction of aperture functions during full fusion in vesicular exocytosis of neurotransmitters.

    Science.gov (United States)

    Amatore, Christian; Oleinick, Alexander I; Svir, Irina

    2010-01-18

    Individual vesicular exocytosis of adrenaline by dense core vesicles in chromaffin cells is considered here as a paradigm of many situations encountered in biology, nanosciences and drug delivery in which a spherical container releases in the external environment through gradual uncovering of its surface. A procedure for extracting the aperture (opening) function of a biological vesicle fusing with a cell membrane from the released molecular flux of neurotransmitter as monitored by amperometry has been devised based on semi-analytical expressions derived in a former work [C. Amatore, A. I. Oleinick, I. Svir, ChemPhysChem 2009, 10, DOI: 10.1002/cphc.200900646]. This precise analysis shows that in the absence of direct information about the radius of the vesicle or about the concentration of the adrenaline cation stored by the vesicle matrix, current spikes do not contain enough information to determine the maximum aperture angle. Yet, a statistical analysis establishes that this maximum aperture angle is most probably less than a few tens of degrees, which suggests that full fusion is a very improbable event.

  5. Recombinant vesicular stomatitis virus vaccine vectors expressing filovirus glycoproteins lack neurovirulence in nonhuman primates.

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    Chad E Mire

    Full Text Available The filoviruses, Marburg virus and Ebola virus, cause severe hemorrhagic fever with high mortality in humans and nonhuman primates. Among the most promising filovirus vaccines under development is a system based on recombinant vesicular stomatitis virus (rVSV that expresses an individual filovirus glycoprotein (GP in place of the VSV glycoprotein (G. The main concern with all replication-competent vaccines, including the rVSV filovirus GP vectors, is their safety. To address this concern, we performed a neurovirulence study using 21 cynomolgus macaques where the vaccines were administered intrathalamically. Seven animals received a rVSV vector expressing the Zaire ebolavirus (ZEBOV GP; seven animals received a rVSV vector expressing the Lake Victoria marburgvirus (MARV GP; three animals received rVSV-wild type (wt vector, and four animals received vehicle control. Two of three animals given rVSV-wt showed severe neurological symptoms whereas animals receiving vehicle control, rVSV-ZEBOV-GP, or rVSV-MARV-GP did not develop these symptoms. Histological analysis revealed major lesions in neural tissues of all three rVSV-wt animals; however, no significant lesions were observed in any animals from the filovirus vaccine or vehicle control groups. These data strongly suggest that rVSV filovirus GP vaccine vectors lack the neurovirulence properties associated with the rVSV-wt parent vector and support their further development as a vaccine platform for human use.

  6. Pesquisaje de litiasis vesicular en un sector de población supuestamente sana

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    Lázaro Yera Abreus

    1997-06-01

    Full Text Available Se hace un estudio de frecuencia de litiasis vesicular en un sector de población supuestamente sana, en el que se encontró una frecuencia de la afección de un 6,2 %, el predominio de las personas de la raza blanca sobre las de la raza negra fue de sólo 1,8:1; la afección es mucho más frecuente en el sexo femenino que en el masculino (proporción de 9:1 y en personas mayores de 40 años (60 % con sobrepeso u obesas (85 %, y puede cursar de forma totalmente asintomática en el 50 % de los casos.A study of the frequency of vasicular lithiasis in an apparently sound sector of the population was conducted. It was found a frequency of affection of 6.2%. The predominance of the white race over the black one was just 1.8:1. This affection is much more common in the females than in the males (proportion 9:1, and among individuals over 40 (60%, who are overweight or obese (85%. It may be completely asymptomatic in 50% of the cases.

  7. Factors influencing survival of vesicular-arbuscular mycorrhiza propagules during topsoil storage

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.M.; Carnes, B.A.; Moorman, T.B.

    1985-01-01

    The survival dynamics of vesicular-arbuscular mycorrhizal fungi were determined, (using a bioassay procedure) for soils stored from 0.5 to 6.0 years in topsoil stockpiles associated with a coal surface-mine in the western United States. Propagule mortality could best be related to in situ soil moisture potential using a piecewise regression model (R/sup 2/ = 0.57; P less than or equal to 0.001) with the breaking point occurring at -2 MPa. The addition of length of storage time was found to contribute significantly to the accuracy of the model (R/sup 2/ = 0.70; P less than or equal to 0.001). In addition, the piece-wise nature of the data suggested two separate populations of VAM fungi - those propagules found in soils with moisture potentials less than -2 MPa and those occurring in soils with moisture potentials greater than -2 MPa. Soil moisture and length of storage time had differing effects on each of these populations. When water potential was less than -2 MPa, moisture was an important predictor of inoculum (P < 0.001), while length of storage had little predictive capability (P = 0.17). However, when water potentials were greater than -2 MPa, the predictive importance of soil moisture (P = 0.86) and length of storage (P = 0.04) were reversed. The significance of these findings to topsoil replacement and subsequent plant community development are discussed. 28 references, 2 figures, 2 tables.

  8. Fabrication of Photofunctional Nanoporous Membrane and Its Photoinactivation Effect of Vesicular Stomatitis Virus

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    Kang-Kyun Wang

    2012-01-01

    Full Text Available Fabrication and photophysical study of photofunctional nanoporous alumina membrane (PNAM were performed, and its application of photodynamic antimicrobial chemotherapy (PACT was investigated. Nanoporous alumina membrane (NAM was fabricated by two-step aluminium anodic oxidation process. Surface of the fabricated NAM was modified with organo-silane agent to induce covalent bonding between NAM and a photosensitizer (PtCP: [5,10,15-triphenyl-20-(4-methoxycarbonylphenyl-porphyrin] platinum. PtCP was covalently bonded to the surface of the modified NAM by nucleophilic acyl substitution reaction process. The morphology and the photophysical properties of the fabricated PNAM were confirmed with field emission scanning electron microscope (FE-SEM, steady-state spectroscopies, and nanosecond laser-induced time-resolved spectroscopy. For the efficacy study of PNAM in PACT, an enveloped animal virus, vesicular stomatitis virus (VSV, was utilized as a target organism. Antiviral effect of the PNAM-PACT was measured by the extent of suppression of plaque-forming units (PFU after the light irradiation. In the cultures inoculated with PACT-treated VSV, the suppression of PFU was prominent, which demonstrates that PNAM is a potential bio clean-up tool.

  9. Formation and Stability of Prebiotically Relevant Vesicular Systems in Terrestrial Geothermal Environments.

    Science.gov (United States)

    Joshi, Manesh Prakash; Samanta, Anupam; Tripathy, Gyana Ranjan; Rajamani, Sudha

    2017-11-30

    Terrestrial geothermal fields and oceanic hydrothermal vents are considered as candidate environments for the emergence of life on Earth. Nevertheless, the ionic strength and salinity of oceans present serious limitations for the self-assembly of amphiphiles, a process that is fundamental for the formation of first protocells. Consequently, we systematically characterized the efficiency of amphiphile assembly, and vesicular stability, in terrestrial geothermal environments, both, under simulated laboratory conditions and in hot spring water samples (collected from Ladakh, India, an Astrobiologically relevant site). Combinations of prebiotically pertinent fatty acids and their derivatives were evaluated for the formation of vesicles in aforesaid scenarios. Additionally, the stability of these vesicles was characterized over multiple dehydration-rehydration cycles, at elevated temperatures. Among the combinations that were tested, mixtures of fatty acid and its glycerol derivatives were found to be the most robust, also resulting in vesicles in all of the hot spring waters that were tested. Importantly, these vesicles were stable at high temperatures, and this fatty acid system retained its vesicle forming propensity, even after multiple cycles of dehydration-rehydration. The remaining systems, however, formed vesicles only in bicine buffer. Our results suggest that certain prebiotic compartments would have had a selective advantage in terrestrial geothermal niches. Significantly, our study highlights the importance of validating results that are obtained under 'buffered' laboratory conditions, by verifying their plausibility in prebiotically analogous environments.

  10. Vesicular-arbuscular-/ecto-mycorrhiza succession in seedlings of. Eucalyptus spp.

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    Santos Vera Lúcia dos

    2001-01-01

    Full Text Available The occurrence of vesicular-arbuscular mycorrhizae (AM and ectomycorrhizae (ECM in the same root system was observed when species of Eucalyptus urophylla S.T. Blake, E. citriodora Hook f., E. grandis W. Hill ex Maiden, E. cloeziana F. Muell. and E. camaldulensis Dehnh were simultaneously inoculated with Glomus etunicatum Becker & Gederman and Pisolithus tinctorius (Per. Cocker & Couch, isolate Pt 90A. The succession between the two fungi was observed. In general ectomycorrhizal colonization increased followed by a decrease in AM. Pisolithus tinctorius was favored in simultaneous inoculation with G. etunicatum, and the positive effect of the simultaneous inoculation of both fungi in the percent colonization by the AM fungus occurred up to 60 days after inoculation. After 120 days, colonization of roots by G. etunicatum decreased in the presence of P. tinctorius. When inoculated simultaneously, the proportion of AM and ECM varied with evaluation time, while the combined percentage of mycorrhizal roots approached the maximum and remained more or less constant after 60 days, suggesting that there could be competition between the fungi for limiting substrate. The maximum percent mycorrhizal colonization varied with Eucalyptus species and the highest value was observed for E. camaldulensis, followed in order by E. citriodora, E. urophylla, E. grandis and E. cloeziana.

  11. Seasonality of vesicular-arbuscular mycorrhizae in sedges in a semi-arid tropical grassland

    Science.gov (United States)

    Muthukumar, T.; Udaiyan, K.

    2002-10-01

    Vesicular-arbuscular mycorrhizal (VAM) colonization and spore numbers in the rhizosphere of Cyperus iria L. and C. rotundus L., growing in a semi-arid tropical grassland, was studied during the 1993 and 1994 monsoons. In addition, climatic and chemical properties of the soils were determined in order to investigate their influence on mycorrhizal variables. VAM fungal association in the sedges was confirmed by plant- and root-trap culture techniques. The soil nutrients exhibited seasonal variations, but were highly variable between years. Intercellular hyphae and vesicles with occasional intraradical spores characterized mycorrhizal association in sedges. Dark septate fungi also colonized roots of sedges. Temporal variations in mycorrhizal colonization and spore numbers occurred, indicating seasonality. However, the patterns of mycorrhizal colonization and spore numbers were different during both the years. The VAM fungal structures observed were intercellular hyphae and vesicles. Changes in the proportion of root length with VAM structures, total colonization levels and spore numbers were related to climatic and edaphic factors. However, the intensity of influence of climatic and soil factors on VAM tended to vary with sedge species.

  12. EFFECTS OF CORN CULTIVAR-TILLAGE SYSTEM COMBINATION ON VESICULAR ARBUSCULAR MYCORRHIZAE

    Directory of Open Access Journals (Sweden)

    Joko Prasetyo .

    2011-10-01

    Full Text Available Pengaruh kombinasi  varietas jagung dan sistem olah tanah terhadap mikorisa vesikular arbuskular.  Penelitian telah dilakukan untuk mengevaluasi pengaruh kombinasi sistem olah tanah dan varietas terhadap  populasi mikorisa vesikular arbuskular. Penelitian juga ditujukan untuk mengetahui pengaruh kombinasi varietas jagung dan sistem olah tanah terhadap infeksi mikorisa vesicular arbuskular. Penelitian terdiri atas enam perlakuan yang disusun dalam rancangan acak kelompok. Perlakuan tersebut adalah varietas RR yang ditanam pada sistem olah tanah konservasi  (RRCT, varietas C7 yang ditanam pada sistem olah tanah konservasi (C7CT, varietas Bisma ditanam pada sistem olah tanah konservasi (BCT, varietas RR ditanam pada sistem olah tanah sempurna (RRFT, varietas C7 yang ditanam pada sistem olah tanah sempurna (C7FT, dan varietas Bisma ditanam pada sistem olah tanah sempurna (BFT. Hasil penelitian pada sistem olah tanah konservasi  menunjukkan bahwa varietas RR dan C7 secara nyata dapat menurunkan infeksi mikorisa dibandingkan dengan varietas Bisma. Hasil penelitian juga menunjukkan bahwa pada varietas RR dan C7, olah tanah konservasi secara nyata menurunkan infeksi mikorisa dibandingkan dengan sistem olah tanah sempurna.

  13. Survey of vesicular-arbuscular mycorrhizae in lettuce production in relation to management and soil factors

    Science.gov (United States)

    Miller, R.L.; Jackson, L.E.

    1998-01-01

    The occurrence of vesicular-arbuscular mycorrhizae (VAM) root colonization and spore number in soil was assessed for 18 fields under intensive lettuce (Lactuca sativa L.) production in California during July and August of 1995. Data on management practices and soil characteristics were compiled for each field, and included a wide range of conditions. The relationship between these factors and the occurrence of VAM in these fields was explored with multivariate statistical analysis. VAM colonization of lettuce tended to decrease with the use of chemical inputs, such as pesticides and high amounts of P and N fertilizers. Addition of soil organic matter amendments, the occurrence of other host crops in the rotation, and soil carbon:phosphorus and carbon:nitrogen ratios, were positively associated with VAM colonization of lettuce roots. The number of VAM spores in soil was strongly correlated with the number of other host crops in the rotation, the occurrence of weed hosts and sampling date, but was more affected by general soil conditions than by management inputs. Higher total soil N, C and P, as well as CEC, were inversely related to soil spore number. A glasshouse study of the two primary lettuce types sampled in the field showed no significant differences in the extent of root colonization under similar growing conditions. The results of this study are compared with other studies on the effects of management and soil conditions on mycorrhizal occurrence in agriculture.

  14. Vesicular stomatitis virus as a flexible platform for oncolytic virotherapy against cancer.

    Science.gov (United States)

    Hastie, Eric; Grdzelishvili, Valery Z

    2012-12-01

    Oncolytic virus (OV) therapy is an emerging anti-cancer approach that utilizes viruses to preferentially infect and kill cancer cells, while not harming healthy cells. Vesicular stomatitis virus (VSV) is a prototypic non-segmented, negative-strand RNA virus with inherent OV qualities. Antiviral responses induced by type I interferon pathways are believed to be impaired in most cancer cells, making them more susceptible to VSV than normal cells. Several other factors make VSV a promising OV candidate for clinical use, including its well-studied biology, a small, easily manipulated genome, relative independence of a receptor or cell cycle, cytoplasmic replication without risk of host-cell transformation, and lack of pre-existing immunity in humans. Moreover, various VSV-based recombinant viruses have been engineered via reverse genetics to improve oncoselectivity, safety, oncotoxicity and stimulation of tumour-specific immunity. Alternative delivery methods are also being studied to minimize premature immune clearance of VSV. OV treatment as a monotherapy is being explored, although many studies have employed VSV in combination with radiotherapy, chemotherapy or other OVs. Preclinical studies with various cancers have demonstrated that VSV is a promising OV; as a result, a human clinical trial using VSV is currently in progress.

  15. Ostwald ripening growth mechanism of gold nanotriangles in vesicular template phases.

    Science.gov (United States)

    Liebig, Ferenc; Thunemann, Andreas F; Koetz, Joachim

    2016-10-03

    The mechanism of nanotriangle formation in multivesicular vesicles (MMV) is investigated by using time dependent SAXS measurements in combination with UV-vis spectroscopy, light and transmission electron microscopy. In the first time period 6.5 nm sized spherical gold nanoparticles are formed inside of the vesicles, which build up soft nanoparticle aggregates. In situ SAXS experiments show a linear increase of the volume and molar mass of nanotriangles in the second time period. The volume growth rate of the triangles is 16.1 nm3/min and the growth rate in vertical direction only 0.02 nm/min. Therefore, flat nanotriangles with a thickness of 7 nm and diameters of 23 nm are formed. This process can be described by a diffusion-limited Ostwald ripening growth mechanism. TEM micrographs visualize soft coral-like structures with thin nanoplatelets at the periphery of the aggregates, which disaggregate in the third time period into nanotriangles and spherical particles. The 16 times faster growth of nanotriangles in lateral than that in vertical direction is related to the adsorption of symmetry breaking components, i.e., AOT and the polyampholyte PalPhBisCarb, on the {111} facets of the gold nanoplatelets in combination with confinement effects of the vesicular template phase.

  16. Conformational Studies on γ - Benzyl- L- Glutamate and L- Valine Containing Block Copolypeptides

    OpenAIRE

    Ajay Kumar

    2010-01-01

    Conformational studies on γ - benzyl-L- glutamate and L- valine containing block copolypeptides are reported using IR and CD spectra. The block copolypeptides contain valine block in the center and on both sides of the valine are γ - benzyl- L- glutamate blocks. The changes in conformation with increase in chain length of γ - benzyl- L- glutamate blocks are observed. When the chain length of γ - benzyl-L- glutamate block is 13, the block copolypeptide crystallized into beta conformation. With...

  17. Temperature differentially facilitates spontaneous but not evoked glutamate release from cranial visceral primary afferents.

    Directory of Open Access Journals (Sweden)

    Jessica A Fawley

    Full Text Available Temperature is fundamentally important to all biological functions including synaptic glutamate release. Vagal afferents from the solitary tract (ST synapse on second order neurons in the nucleus of the solitary tract, and glutamate release at this first central synapse controls autonomic reflex function. Expression of the temperature-sensitive Transient Receptor Potential Vanilloid Type 1 receptor separates ST afferents into C-fibers (TRPV1+ and A-fibers (TRPV1-. Action potential-evoked glutamate release is similar between C- and A-fiber afferents, but TRPV1 expression facilitates a second form of synaptic glutamate release in C-fibers by promoting substantially more spontaneous glutamate release. The influence of temperature on different forms of glutamate release is not well understood. Here we tested how temperature impacts the generation of evoked and spontaneous release of glutamate and its relation to TRPV1 expression. In horizontal brainstem slices of rats, activation of ST primary afferents generated synchronous evoked glutamate release (ST-eEPSCs at constant latency whose amplitude reflects the probability of evoked glutamate release. The frequency of spontaneous EPSCs in these same neurons measured the probability of spontaneous glutamate release. We measured both forms of glutamate from each neuron during ramp changes in bath temperature of 4-5 °C. Spontaneous glutamate release from TRPV1+ closely tracked with these thermal changes indicating changes in the probability of spontaneous glutamate release. In the same neurons, temperature changed axon conduction registered as latency shifts but ST-eEPSC amplitudes were constant and independent of TRPV1 expression. These data indicate that TRPV1-operated glutamate release is independent of action potential-evoked glutamate release in the same neurons. Together, these support the hypothesis that evoked and spontaneous glutamate release originate from two pools of vesicles that are

  18. 78 FR 74115 - Monosodium Glutamate From the People's Republic of China and the Republic of Indonesia...

    Science.gov (United States)

    2013-12-10

    ... International Trade Administration Monosodium Glutamate From the People's Republic of China and the Republic of... investigations of monosodium glutamate from Indonesia and the PRC.\\1\\ Currently, the preliminary determinations are due no later than December 27, 2013. \\1\\ See Monosodium Glutamate from the People's Republic of...

  19. 40 CFR 721.3820 - L-Glutamic acid, N-(1-oxododecyl)-, disodium salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false L-Glutamic acid, N-(1-oxododecyl... Specific Chemical Substances § 721.3820 L-Glutamic acid, N-(1-oxododecyl)-, disodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as L-Glutamic...

  20. 40 CFR 180.1187 - L-glutamic acid; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false L-glutamic acid; exemption from the... Exemptions From Tolerances § 180.1187 L-glutamic acid; exemption from the requirement of a tolerance. L-glutamic acid is exempt from the requirement of a tolerance on all food commodities when used in accordance...

  1. 40 CFR 721.3821 - L-Glutamic acid, N-(1-oxododecyl)-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false L-Glutamic acid, N-(1-oxododecyl... Substances § 721.3821 L-Glutamic acid, N-(1-oxododecyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as L-Glutamic acid, N-(1-oxododecyl)- (PMN P...

  2. [The comparative investigation of antihypoxia activity of glutamic and N-acetylglutamic acids].

    Science.gov (United States)

    Makarova, L M; Pogorelyĭ, V E

    2013-01-01

    Comparative study of antihypoxic activity of glutamic and N-acetylglutamic acid in doses of 1, 10, 50 and 100 mg/kg was realized. It was experimentally ascertained that the most apparent antihypoxic action of study objects occurs in conditions of hypobaric hypoxia of acetylated derivative of glutamic acid considerably exceeds glutamic acid.

  3. Probing the cob(II)alamin Cond UctorHhypothesis with Glutamate ...

    African Journals Online (AJOL)

    The assembly of coenzyme B12 (adenosylcobalamin) with recombinant components GlmS and GlmE of glutamate mutase from Clostridium cochlearium reconstitutes an active holoenzyme that catalyses the reversible rearrangement between (S)-glutamate and (2S,3S)-3-methylaspartate. Glutamate mutase activity was also ...

  4. Muscle pain sensitivity after glutamate injection is not modified by systemic administration of monosodium glutamate.

    Science.gov (United States)

    Shimada, Akiko; Castrillon, Eduardo; Baad-Hansen, Lene; Ghafouri, Bijar; Gerdle, Björn; Ernberg, Malin; Cairns, Brian; Svensson, Peter

    2015-01-01

    Monosodium glutamate (MSG) is often thought to be associated with headache and craniofacial pains like temporomandibular disorders. This randomized, double-blinded, placebo-controlled study was performed to investigate how ingestion of MSG affects muscle pain sensitivity before and after experimentally induced muscle pain. Sixteen healthy adult subjects participated in 2 sessions with at least 1-week interval between sessions. In each session, two injections of glutamate (Glu, 0.5 M, 0.2 ml) and two injections of saline (0.9%, 0.2 ml) into the masseter and temporalis muscles, respectively, were undertaken, with a 15 min interval between each injection. Injections of saline were made contralateral to Glu injections and done in a randomized order. Participants drank 400 mL of soda mixed with either MSG (150 mg/kg) or NaCl (24 mg/kg, placebo) 30 min before the intramuscular injections. Pressure pain thresholds (PPT), autonomic parameters and pain intensity were assessed prior to (baseline) and 30 min after ingestion of soda, as well as 5 min and 10 min after the intramuscular injections and at the end of the session. Whole saliva samples were collected prior to and 30, 45, 60, and 75 min after the ingestion of soda. MSG administration resulted in a significantly higher Glu level in saliva than administration of NaCl and was associated with a significant increase in systolic blood pressure. Injections of Glu were significantly more painful than injections of NaCl. However, ingestion of MSG did not change the intensity of Glu-evoked pain. Glu injections also significantly increased systolic and diastolic blood pressure, but without an additional effect of MSG ingestion. Glu injections into the masseter muscle significantly reduced the PPT. However, pre-injection MSG ingestion did not significantly alter this effect. Interestingly, PPT was significantly increased in the trapezius after MSG ingestion and intramuscular injection of Glu in the jaw muscles. The main finding

  5. Histological studies of the effects of monosodium glutamate on the ...

    African Journals Online (AJOL)

    Background: The effect of monosodium glutamate used as food additive on the fallopian tubes of adult Wistar rat was investigated. Material and Methods: Adult female Wistar rats (n=24) of average weight of 230g were randomly assigned into three groups A, B and C of (n=8) in each group. The treatment groups (A and B) ...

  6. The effect of monosodium glutamate (MSG) on blood glucose in ...

    African Journals Online (AJOL)

    This study investigates the effect of monosodium glutamate on fasting blood glucose. 18 adult rabbits (1.6 ± 0.20 Kg), procured from the animal house at the College of Medicine, Ambrose Alli University, Ekpoma, and transferred to the Physiology Laboratory of the same institution were used for this study. The animals were ...

  7. Palmitoylethanolamide Inhibits Glutamate Release in Rat Cerebrocortical Nerve Terminals

    Directory of Open Access Journals (Sweden)

    Tzu-Yu Lin

    2015-03-01

    Full Text Available The effect of palmitoylethanolamide (PEA, an endogenous fatty acid amide displaying neuroprotective actions, on glutamate release from rat cerebrocortical nerve terminals (synaptosomes was investigated. PEA inhibited the Ca2+-dependent release of glutamate, which was triggered by exposing synaptosomes to the potassium channel blocker 4-aminopyridine. This release inhibition was concentration dependent, associated with a reduction in cytosolic Ca2+ concentration, and not due to a change in synaptosomal membrane potential. The glutamate release-inhibiting effect of PEA was prevented by the Cav2.1 (P/Q-type channel blocker ω-agatoxin IVA or the protein kinase A inhibitor H89, not affected by the intracellular Ca2+ release inhibitors dantrolene and CGP37157, and partially antagonized by the cannabinoid CB1 receptor antagonist AM281. Based on these results, we suggest that PEA exerts its presynaptic inhibition, likely through a reduction in the Ca2+ influx mediated by Cav2.1 (P/Q-type channels, thereby inhibiting the release of glutamate from rat cortical nerve terminals. This release inhibition might be linked to the activation of presynaptic cannabinoid CB1 receptors and the suppression of the protein kinase A pathway.

  8. Function and importance of glutamate for savory foods.

    Science.gov (United States)

    Loliger, J

    2000-04-01

    Flavoring systems are of vital importance in savory food manufacturing. Many industrially prepared foods are particularly attractive to potential consumers primarily because of their typical flavors. Therefore, it is no surprise that the food industry dealing with these product segments shows great interest in the use of food or food ingredients carrying the typical umami taste and flavor enhancement systems. Figures are provided showing the importance of glutamate in traditional cuisines and also in meals prepared by industrial manufacturing. It is also interesting to see how food intake patterns of glutamate differ from one cultural group to another. The ever-growing importance of balanced food formulations (carbohydrates, fats, proteins and minerals) brings special challenges to the use of different ingredients, requiring development of appropriate flavor delivery systems. Again flavor enhancement is of great importance. Questions about the addition of glutamate or the total glutamate content of foods are of little importance, from a scientific point of view. However, in a given legal framework, important business opportunities can be realized. One of the main concerns of manufacturers of savory food is how to provide the consumer with tasty foods while complying with increasingly severe local legal constraints concerning the use of many potent flavoring systems.

  9. Blood and Brain Glutamate Levels in Children with Autistic Disorder

    Science.gov (United States)

    Hassan, Tamer H.; Abdelrahman, Hadeel M.; Fattah, Nelly R. Abdel; El-Masry, Nagda M.; Hashim, Haitham M.; El-Gerby, Khaled M.; Fattah, Nermin R. Abdel

    2013-01-01

    Despite of the great efforts that move forward to clarify the pathophysiologic mechanisms in autism, the cause of this disorder, however, remains largely unknown. There is an increasing body of literature concerning neurochemical contributions to the pathophysiology of autism. We aimed to determine blood and brain levels of glutamate in children…

  10. Assay of partially purified glutamate dehydrogenase isolated from ...

    African Journals Online (AJOL)

    Glutamate dehydrogenase (E C 1.4.1.1) isolated from the seeds of asparagus beans was partially purified to a factor of 22 by dialysis after fractional precipitation with solid ammonium sulphate at 40 and 60% saturation. A specific activity of 11.78μmol min-1 mg-1 protein was calculated for the partially purified enzyme when ...

  11. Metabotropic glutamate receptors in cultured cerebellar granule cells: developmental profile

    NARCIS (Netherlands)

    Aronica, E.; Condorelli, D. F.; Nicoletti, F.; Dell'Albani, P.; Amico, C.; Balázs, R.

    1993-01-01

    Excitatory amino acid (EAA)-induced polyphosphoinositide (PPI) hydrolysis was studied during the development in culture of cerebellar granule cells. The developmental pattern was similar using metabotropic glutamate (Glu) receptor (mGluR) agonists, including L-Glu, quisqualate, and

  12. probing the cob(ii)alamin conductor hypothesis with glutamate ...

    African Journals Online (AJOL)

    dell

    with a peptide mimic that contains the same number of atoms between Co(III) and the adenosine base. Measurements of the kinetic constants of glutamate mutase with coenzyme B12 and 3',5'- dideoxyadenosylcobalamin suggested similar binding properties of the cofactors to the apo- enzyme. However, the catalytic ...

  13. Effects Of Monosodium Glutamate (MSG) On The Histological ...

    African Journals Online (AJOL)

    An investigation was carried out on the effects of monosodium glutamate (MSG), a commonly ues food additive, on the spinal cord of adult Wistar rats. Twenty-four adult Wistar rats weighing between 180-250g were divided into four groups of six rats per group. Graduated doses of 6mg, 12mg and 18mg per kilogram body ...

  14. Histological Studies of the Effects of Monosodium Glutamate on the ...

    African Journals Online (AJOL)

    Uche

    Annals of Medical and Health Sciences Research – January 2011 – Vol. 1 N0.1. >>>37<<<. Histological Studies of the Effects of Monosodium. Glutamate on the Ovaries of Adult Wistar Rats. Eweka AO* and Om'Iniabohs FAE*. * Department of Anatomy School of Basic Medical Sciences,. College of Medical Sciences ...

  15. Synthesis of Biobased Succinonitrile from Glutamic Acid and Glutamine

    NARCIS (Netherlands)

    Lammens, T.M.; Nôtre, Le J.; Franssen, M.C.R.; Scott, E.L.; Sanders, J.P.M.

    2011-01-01

    Succinonitrile is the precursor of 1,4-diaminobutane, which is used for the industrial production of polyamides. This paper describes the synthesis of biobased succinonitrile from glutamic acid and glutamine, amino acids that are abundantly present in many plant proteins. Synthesis of the

  16. Examining the role of glutamic acid 183 in chloroperoxidase catalysis

    NARCIS (Netherlands)

    Yi, X.; Conesa, A.; Punt, P.J.; Hager, L.P.

    2003-01-01

    Site-directed mutagenesis has been used to investigate the role of glutamic acid 183 in chloroperoxidase catalysis. Based on the x-ray crystallographic structure of chloroperoxidase, Glu-183 is postulated to function on distal side of the heme prosthetic group as an acid-base catalyst in

  17. Anaplerosis for Glutamate Synthesis in the Neonate and in Adulthood

    DEFF Research Database (Denmark)

    Brekke, Eva; Morken, Tora Sund; Walls, Anne B

    2016-01-01

    A central task of the tricarboxylic acid (TCA, Krebs, citric acid) cycle in brain is to provide precursors for biosynthesis of glutamate, GABA, aspartate and glutamine. Three of these amino acids are the partners in the intricate interaction between astrocytes and neurons and form the so-called g...

  18. Continuous glutamate production using an immobilized whole-cell system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.S.; Ryu, D.D.Y.

    1982-10-01

    For the purpose of saving the energy and raw materials required in a glutamate fermentation, an immobilized whole-cell system was prepared and its performance in a continuous reactor system was evaluated. Corynebacterium glutamicum (a mutant strain of ATCC 13058) whole cell was immobilized in k-carrageenan matrix and the gel structure was strengthened by treatment with a hardening agent. The effective diffusivities of carrageenan gel for glucose and oxygen were formed to decrease significantly with an increase in carrageenan concentration, while the gel strength showed an increasing trend. Based on the physical and chemical properties of carrageenan gel, the immobilized method was improved and the operation of the continuous reactor system was partially optimized. In an air-stirred fermentor, the continuous production of glutamate was carried out. The effect of the dilution rate of glutamate production and operation stability was investigated. The performance of the continuous wbole-cell reactor system was evaluated by measuring glutamate productivity for a period of 30 days; it was found to be far superior to the performance of convention batch reactor systems using free cells.

  19. The effects of Groundnut, Spices, Monosodium Glutamate and Salt ...

    African Journals Online (AJOL)

    This study was intended to determine the effect of salt, groundnut, monosodium glutamate and spices, especially in combinations as used in Yaji, on the histology of the brain. The rats were divided into nine (9) groups (A – I) of eight rats (8) each. Groups A, B, C, D, E, F, G, H, constituted the test groups whereas group I ...

  20. Histochemical Studies of the Effects of Monosodium Glutamate on ...

    African Journals Online (AJOL)

    Uche

    One such food additive is. Monosodium Glutamate (MSG) and it is sold in most open market stalls and stores in Nigeria as. “Ajinomoto” marketed by West African Seasoning. Company Limited. Some pathological conditions like cancers result from the body‟s normal responses to abnormal environmental influences.

  1. Antibodies to a recombinant glutamate-rich Plasmodium falciparum protein

    DEFF Research Database (Denmark)

    Hogh, B; Petersen, E; Dziegiel, Morten Hanefeld

    1992-01-01

    A Plasmodium falciparum antigen gene coding for a 220-kD glutamate-rich protein (GLURP) has been cloned, and the 783 C-terminal amino acids of this protein (GLURP489-1271) have been expressed as a beta-galactosidase fusion protein in Escherichia coli. The encoded 783 amino acid residues contain two...

  2. Evolution and expression analysis of the soybean glutamate ...

    Indian Academy of Sciences (India)

    Evolution and expression analysis of the soybean glutamate decarboxylase gene family. TAE KYUNG HYUN, SEUNG HEE EOM, XIAO HAN and JU-SUNG KIM http://www.ias.ac.in/jbiosci. J. Biosci. 39(5), December 2014, 899–907, © Indian Academy of Sciences. Supplementary material. Supplementary figure 1.

  3. On the potential role of glutamate transport in mental fatigue

    Directory of Open Access Journals (Sweden)

    Hansson Elisabeth

    2004-11-01

    Full Text Available Abstract Mental fatigue, with decreased concentration capacity, is common in neuroinflammatory and neurodegenerative diseases, often appearing prior to other major mental or physical neurological symptoms. Mental fatigue also makes rehabilitation more difficult after a stroke, brain trauma, meningitis or encephalitis. As increased levels of proinflammatory cytokines are reported in these disorders, we wanted to explore whether or not proinflammatory cytokines could induce mental fatigue, and if so, by what mechanisms. It is well known that proinflammatory cytokines are increased in major depression, "sickness behavior" and sleep deprivation, which are all disorders associated with mental fatigue. Furthermore, an influence by specific proinflammatory cytokines, such as interleukin (IL-1, on learning and memory capacities has been observed in several experimental systems. As glutamate signaling is crucial for information intake and processing within the brain, and due to the pivotal role for glutamate in brain metabolism, dynamic alterations in glutamate transmission could be of pathophysiological importance in mental fatigue. Based on this literature and observations from our own laboratory and others on the role of astroglial cells in the fine-tuning of glutamate neurotransmission we present the hypothesis that the proinflammatory cytokines tumor necrosis factor-α, IL-1β and IL-6 could be involved in the pathophysiology of mental fatigue through their ability to attenuate the astroglial clearance of extracellular glutamate, their disintegration of the blood brain barrier, and effects on astroglial metabolism and metabolic supply for the neurons, thereby attenuating glutamate transmission. To test whether our hypothesis is valid or not, brain imaging techniques should be applied with the ability to register, over time and with increasing cognitive loading, the extracellular concentrations of glutamate and potassium (K+ in humans suffering from

  4. On the potential role of glutamate transport in mental fatigue.

    Science.gov (United States)

    Rönnbäck, Lars; Hansson, Elisabeth

    2004-11-04

    Mental fatigue, with decreased concentration capacity, is common in neuroinflammatory and neurodegenerative diseases, often appearing prior to other major mental or physical neurological symptoms. Mental fatigue also makes rehabilitation more difficult after a stroke, brain trauma, meningitis or encephalitis. As increased levels of proinflammatory cytokines are reported in these disorders, we wanted to explore whether or not proinflammatory cytokines could induce mental fatigue, and if so, by what mechanisms.It is well known that proinflammatory cytokines are increased in major depression, "sickness behavior" and sleep deprivation, which are all disorders associated with mental fatigue. Furthermore, an influence by specific proinflammatory cytokines, such as interleukin (IL)-1, on learning and memory capacities has been observed in several experimental systems. As glutamate signaling is crucial for information intake and processing within the brain, and due to the pivotal role for glutamate in brain metabolism, dynamic alterations in glutamate transmission could be of pathophysiological importance in mental fatigue. Based on this literature and observations from our own laboratory and others on the role of astroglial cells in the fine-tuning of glutamate neurotransmission we present the hypothesis that the proinflammatory cytokines tumor necrosis factor-alpha, IL-1beta and IL-6 could be involved in the pathophysiology of mental fatigue through their ability to attenuate the astroglial clearance of extracellular glutamate, their disintegration of the blood brain barrier, and effects on astroglial metabolism and metabolic supply for the neurons, thereby attenuating glutamate transmission. To test whether our hypothesis is valid or not, brain imaging techniques should be applied with the ability to register, over time and with increasing cognitive loading, the extracellular concentrations of glutamate and potassium (K+) in humans suffering from mental fatigue. At

  5. Glutamate-mediated excitotoxicity in schizophrenia: a review.

    Science.gov (United States)

    Plitman, Eric; Nakajima, Shinichiro; de la Fuente-Sandoval, Camilo; Gerretsen, Philip; Chakravarty, M Mallar; Kobylianskii, Jane; Chung, Jun Ku; Caravaggio, Fernando; Iwata, Yusuke; Remington, Gary; Graff-Guerrero, Ariel

    2014-10-01

    Findings from neuroimaging studies in patients with schizophrenia suggest widespread structural changes although the mechanisms through which these changes occur are currently unknown. Glutamatergic activity appears to be increased in the early phases of schizophrenia and may contribute to these structural alterations through an excitotoxic effect. The primary aim of this review was to describe the possible role of glutamate-mediated excitotoxicity in explaining the presence of neuroanatomical changes within schizophrenia. A Medline(®) literature search was conducted, identifying English language studies on the topic of glutamate-mediated excitotoxicity in schizophrenia, using the terms "schizophreni" and "glutam" and (("MRS" or "MRI" or "magnetic resonance") or ("computed tomography" or "CT")). Studies concomitantly investigating glutamatergic activity and brain structure in patients with schizophrenia were included. Results are discussed in the context of findings from preclinical studies. Seven studies were identified that met the inclusion criteria. These studies provide inconclusive support for the role of glutamate-mediated excitotoxicity in the occurrence of structural changes within schizophrenia, with the caveat that there is a paucity of human studies investigating this topic. Preclinical data suggest that an excitotoxic effect may occur as a result of a paradoxical increase in glutamatergic activity following N-methyl-D-aspartate receptor hypofunction. Based on animal literature, glutamate-mediated excitotoxicity may account for certain structural changes present in schizophrenia, but additional human studies are required to substantiate these findings. Future studies should adopt a longitudinal design and employ magnetic resonance imaging techniques to investigate whether an association between glutamatergic activity and structural changes exists in patients with schizophrenia. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  6. Prefrontal cortex glutamate correlates with mental perspective-taking.

    Directory of Open Access Journals (Sweden)

    Christiane Montag

    Full Text Available BACKGROUND: Dysfunctions in theory of mind and empathic abilities have been suggested as core symptoms in major psychiatric disorders including schizophrenia and autism. Since self monitoring, perspective taking and empathy have been linked to prefrontal (PFC and anterior cingulate cortex (ACC function, neurotransmitter variations in these areas may account for normal and pathological variations of these functions. Converging evidence indicates an essential role of glutamatergic neurotransmission in psychiatric diseases with pronounced deficits in empathy. However, the role of the glutamate system for different dimensions of empathy has not been investigated so far. METHODOLOGY/PRINCIPAL FINDINGS: Absolute concentrations of cerebral glutamate in the ACC, left dorsolateral PFC and left hippocampus were determined by 3-tesla proton magnetic resonance spectroscopy (1H-MRS in 17 healthy individuals. Three dimensions of empathy were estimated by a self-rating questionnaire, the Interpersonal Reactivity Index (IRI. Linear regression analysis showed that dorsolateral PFC glutamate concentration was predicted by IRI factor "perspective taking" (T = -2.710, p = 0.018; adjusted alpha-level of 0.017, Bonferroni but not by "empathic concern" or "personal distress". No significant relationship between IRI subscores and the glutamate levels in the ACC or left hippocampus was detected. CONCLUSIONS/SIGNIFICANCE: This is the first study to investigate the role of the glutamate system for dimensions of theory of mind and empathy. Results are in line with recent concepts that executive top-down control of behavior is mediated by prefrontal glutamatergic projections. This is a preliminary finding that needs a replication in an independent sample.

  7. Tobacco Isoenzyme 1 of NAD(H)-Dependent Glutamate Dehydrogenase Catabolizes Glutamate in Vivo[OA

    Science.gov (United States)

    Purnell, Matthew Peter; Botella, José Ramon

    2007-01-01

    Glutamate (Glu) dehydrogenase (GDH, EC 1.4.1.2–1.4.1.4) catalyzes in vitro the reversible amination of 2-oxoglutarate to Glu. The in vivo direction(s) of the GDH reaction in higher plants and hence the role(s) of this enzyme is unclear, a situation confounded by the existence of isoenzymes comprised totally of either GDH β- (isoenzyme 1) or α- (isoenzyme 7) subunits, as well as another five α-β isoenzyme permutations. To clarify the in vivo direction of the reaction catalyzed by GDH isoenzyme 1, [15N]Glu was supplied to roots of two independent transgenic tobacco (Nicotiana tabacum) lines with increased isoenzyme 1 levels (S4-H and S49-H). The [15N]ammonium (NH4+) accumulation rate in these lines was elevated approximately 65% compared with a null segregant control line, indicating that isoenzyme 1 catabolizes Glu in roots. Leaf glutamine synthetase (GS) was inhibited with a GS-specific herbicide to quantify any contribution by GDH toward photorespiratory NH4+ reassimilation. Transgenic line S49-H did not show enhanced resistance to the herbicide, indicating that the large pool of isoenzyme 1 in S49-H leaves was unable to compensate for GS and suggesting that isoenzyme 1 does not assimilate NH4+ in vivo. PMID:17114271

  8. Laser-scanning astrocyte mapping reveals increased glutamate-responsive domain size and disrupted maturation of glutamate uptake following neonatal cortical freeze-lesion

    Directory of Open Access Journals (Sweden)

    Mortiz eArmbruster

    2014-09-01

    Full Text Available Astrocytic uptake of glutamate shapes extracellular neurotransmitter dynamics, receptor activation, and synaptogenesis. During development, glutamate transport becomes more robust. How neonatal brain insult affects the functional maturation of glutamate transport remains unanswered. Neonatal brain insult can lead to developmental delays, cognitive losses, and epilepsy; the disruption of glutamate transport is known to cause changes in synaptogenesis, receptor activation, and seizure. Using the neonatal freeze-lesion (FL model, we have investigated how insult affects the maturation of astrocytic glutamate transport. As lesioning occurs on the day of birth, a time when astrocytes are still functionally immature, this model is ideal for identifying changes in astrocyte maturation following insult. Reactive astrocytosis, astrocyte proliferation, and in vitro hyperexcitability are known to occur in this model. To probe astrocyte glutamate transport with better spatial precision we have developed a novel technique, Laser Scanning Astrocyte Mapping (LSAM, which combines glutamate transport current (TC recording from astrocytes with laser scanning glutamate photolysis. LSAM allows us to identify the area from which a single astrocyte can transport glutamate and to quantify spatial heterogeneity in the rate of glutamate clearance kinetics within that domain. Using LSAM, we report that cortical astrocytes have an increased glutamate-responsive area following FL and that TCs have faster decay times in distal, as compared to proximal processes. Furthermore, the developmental shift from GLAST- to GLT-1-dominated clearance is disrupted following FL. These findings introduce a novel method to probe astrocyte glutamate uptake and show that neonatal cortical FL disrupts the functional maturation of cortical astrocytes.

  9. Deletion of genes involved in glutamate metabolism to improve poly-gamma-glutamic acid production in B. amyloliquefaciens LL3.

    Science.gov (United States)

    Zhang, Wei; He, Yulian; Gao, Weixia; Feng, Jun; Cao, Mingfeng; Yang, Chao; Song, Cunjiang; Wang, Shufang

    2015-02-01

    Here, we attempted to elevate poly-gamma-glutamic acid (γ-PGA) production by modifying genes involved in glutamate metabolism in Bacillus amyloliquefaciens LL3. Products of rocR, rocG and gudB facilitate the conversion from glutamate to 2-oxoglutarate in Bacillus subtillis. The gene odhA is responsible for the synthesis of a component of the 2-oxoglutarate dehydrogenase complex that catalyzes the oxidative decarboxylation of 2-oxoglutarate to succinyl coenzyme A. In-frame deletions of these four genes were performed. In shake flask experiments the gudB/rocG double mutant presented enhanced production of γ-PGA, a 38 % increase compared with wild type. When fermented in a 5-L fermenter with pH control, the γ-PGA yield of the rocR mutant was increased to 5.83 g/L from 4.55 g/L for shake flask experiments. The gudB/rocG double mutant produced 5.68 g/L γ-PGA compared with that of 4.03 g/L for the wild type, a 40 % increase. Those results indicated the possibility of improving γ-PGA production by modifying glutamate metabolism, and identified potential genetic targets to improve γ-PGA production.

  10. Chikungunya, Influenza, Nipah, and Semliki Forest Chimeric Viruses with Vesicular Stomatitis Virus: Actions in the Brain.

    Science.gov (United States)

    van den Pol, Anthony N; Mao, Guochao; Chattopadhyay, Anasuya; Rose, John K; Davis, John N

    2017-03-15

    Recombinant vesicular stomatitis virus (VSV)-based chimeric viruses that include genes from other viruses show promise as vaccines and oncolytic viruses. However, the critical safety concern is the neurotropic nature conveyed by the VSV glycoprotein. VSVs that include the VSV glycoprotein (G) gene, even in most recombinant attenuated strains, can still show substantial adverse or lethal actions in the brain. Here, we test 4 chimeric viruses in the brain, including those in which glycoprotein genes from Nipah, chikungunya (CHIKV), and influenza H5N1 viruses were substituted for the VSV glycoprotein gene. We also test a virus-like vesicle (VLV) in which the VSV glycoprotein gene is expressed from a replicon encoding the nonstructural proteins of Semliki Forest virus. VSVΔG-CHIKV, VSVΔG-H5N1, and VLV were all safe in the adult mouse brain, as were VSVΔG viruses expressing either the Nipah F or G glycoprotein. In contrast, a complementing pair of VSVΔG viruses expressing Nipah G and F glycoproteins were lethal within the brain within a surprisingly short time frame of 2 days. Intranasal inoculation in postnatal day 14 mice with VSVΔG-CHIKV or VLV evoked no adverse response, whereas VSVΔG-H5N1 by this route was lethal in most mice. A key immune mechanism underlying the safety of VSVΔG-CHIKV, VSVΔG-H5N1, and VLV in the adult brain was the type I interferon response; all three viruses were lethal in the brains of adult mice lacking the interferon receptor, suggesting that the viruses can infect and replicate and spread in brain cells if not blocked by interferon-stimulated genes within the brain.IMPORTANCE Vesicular stomatitis virus (VSV) shows considerable promise both as a vaccine vector and as an oncolytic virus. The greatest limitation of VSV is that it is highly neurotropic and can be lethal within the brain. The neurotropism can be mostly attributed to the VSV G glycoprotein. Here, we test 4 chimeric viruses of VSV with glycoprotein genes from Nipah

  11. mRNA cap methylation influences pathogenesis of vesicular stomatitis virus in vivo.

    Science.gov (United States)

    Ma, Yuanmei; Wei, Yongwei; Zhang, Xiaodong; Zhang, Yu; Cai, Hui; Zhu, Yang; Shilo, Konstantin; Oglesbee, Michael; Krakowka, Steven; Whelan, Sean P J; Li, Jianrong

    2014-03-01

    One role of mRNA cap guanine-N-7 (G-N-7) methylation is to facilitate the efficient translation of mRNA. The role of mRNA cap ribose 2'-O methylation is enigmatic, although recent work has implicated this as a signature to avoid detection of RNA by the innate immune system (S. Daffis, K. J. Szretter, J. Schriewer, J. Q. Li, S. Youn, J. Errett, T. Y. Lin, S. Schneller, R. Zust, H. P. Dong, V. Thiel, G. C. Sen, V. Fensterl, W. B. Klimstra, T. C. Pierson, R. M. Buller, M. Gale, P. Y. Shi, M. S. Diamond, Nature 468:452-456, 2010, doi:10.1038/nature09489). Working with vesicular stomatitis virus (VSV), we previously showed that a panel of recombinant VSVs carrying mutations at a predicted methyltransferase catalytic site (rVSV-K1651A, -D1762A, and -E1833Q) or S-adenosylmethionine (SAM) binding site (rVSV-G1670A, -G1672A, and -G4A) were defective in cap methylation and were also attenuated for growth in cell culture. Here, we analyzed the virulence of these recombinants in mice. We found that rVSV-K1651A, -D1762A, and -E1833Q, which are defective in both G-N-7 and 2'-O methylation, were highly attenuated in mice. All three viruses elicited a high level of neutralizing antibody and provided full protection against challenge with the virulent VSV. In contrast, mice inoculated with rVSV-G1670A and -G1672A, which are defective only in G-N-7 methylation, were attenuated in vivo yet retained a low level of virulence. rVSV-G4A, which is completely defective in both G-N-7 and 2'-O methylation, also exhibited low virulence in mice despite the fact that productive viral replication was not detected in lung and brain. Taken together, our results suggest that abrogation of viral mRNA cap methylation can serve as an approach to attenuate VSV, and perhaps other nonsegmented negative-strand RNA viruses, for potential application as vaccines and viral vectors. Nonsegmented negative-sense (NNS) RNA viruses include a wide range of significant human, animal, and plant pathogens. For many

  12. Factores de riesgo en la litiasis vesicular: Estudio en pacientes colecistectomizados

    Directory of Open Access Journals (Sweden)

    Carlos A Romero Díaz

    1999-08-01

    Full Text Available Se realizó un estudio prospectivo desde diciembre de 1991 hasta noviembre de 1997, en 276 pacientes ingresados e intervenidos quirúrgicamente con el diagnóstico de litiasis vesicular. Dichos pacientes se intervinieron por nuestro grupo básico de trabajo y en su mayoría eran remitidos por médicos de la familia graduados en nuestra facultad. Se clasificaron los cálculos en pigmentarios y de colesterol según sus características macroscópicas al corte, y se realizó una encuesta con los posibles factores de riesgos. Predominaron los cálculos de colesterol (76,1 % sobre los pigmentarios, y existió predominio del sexo femenino sobre el masculino en relación de 4:1. El diagnóstico de litiasis vesicular se efectuó con mayor frecuencia en la cuarta y quinta décadas de la vida, mientras los pigmentarios se observaron con mayor frecuencia en edades más avanzadas. La obesidad (39,5 %, la diabetes mellitus (19,5 % y la paridad (31,8 % constituyeron los principales factores de riesgo, por lo que se deberá tomar en cuenta los antecedentes de litiasis en familiares de primera línea y la ingestión de anticonceptivos orales. En los estados hemolíticos predominaron los cálculos pigmentarios y se demostró la relación de las hiperlipoproteinemias de las fracciones IIb y IV con la colelitiasis. Sólo el 34,5 % de los bilicultivos realizados tuvieron crecimiento bacteriano, y fueron la Escherichia coli y el estreptococo los más aisladosA prospective study of 276 patients admitted and operated on with the diagnosis of cholelithiasis was conducted from December, 1991, to November, 1997. These patients were operated on by our basic working group and most of them were referred by family physicians graduated in our Faculty. Gallstones were classified into pigment gallstones and cholesterol gallstones according to their macroscopic characteristics on cutting. A survey was done with the possible risk factors. Cholesterol gallstones (76

  13. Singleton reactors in the diagnosis of swine vesicular disease: the role of coxsackievirus B5.

    Science.gov (United States)

    Moonen, P; Van Poelwijk, F; Moormann, R; Dekker, A

    2000-10-01

    Swine vesicular disease virus (SVDV) and Coxsackie B5 virus (CVB5) are closely related viruses that can infect swine and man and give rise to cross-reacting serum antibodies. It is, therefore, possible that SVD antibodies found in serologic screenings of pigs are induced by CVB5. Single positive animals found in screening programmes are generally referred to as singleton reactors (SR). To determine whether SR in SVDV screenings are induced by CVB5 infection, virus neutralisation tests (VNTs) and radioimmunoprecipitation assays (RIPA) were carried out on sera of SR, sera of pigs experimentally infected with SVDV, and sera from pigs vaccinated with CVB5 isolates. The SR sera reacted repeatedly positive in the SVDV UKG/27/72 VNT, but reacted differently in three other VNTs (SVDV NET/1/92, CVB5A, and CVB5B). The VNT titres obtained with the SR sera revealed a correlation between both SVDV strains, and also between both CVB5 stains, but no correlation was found between SVD and CVB5 VNT titres. Sera of experimentally infected (SVDV) or vaccinated (CVB5) pigs showed titres in all four neutralisation tests. In the RIPA, the reaction patterns of the SR sera varied considerably with all four antigens used, in contrast to sera from pigs experimentally infected with SVDV that reacted with all antigens used, and sera from pigs vaccinated with CVB5 that reacted only with CVB5 antigens. The results presented in this paper show that neither CVB5 nor SVDV infections are the only cause of the SR phenomenon. Testing for CVB5 specific antibodies can reduce the number of SR sera in the serodiagnosis of SVDV.

  14. Dopamine, vesicular transporters, and dopamine receptor expression in rat major salivary glands.

    Science.gov (United States)

    Tomassoni, Daniele; Traini, Enea; Mancini, Manuele; Bramanti, Vincenzo; Mahdi, Syed Sarosh; Amenta, Francesco

    2015-09-01

    The localization of dopamine stores and the expression and localization of dopamine (DAT) and vesicular monoamine transporters (VMAT) type-1 and -2 and of dopamine D1-like and D2-like receptor subtypes were investigated in rat submandibular, sublingual, and parotid salivary glands by HPLC with electrochemical detection, as well as immunochemical and immunohistochemical techniques. Male Wistar rats of 2 mo of age were used. The highest dopamine levels were measured in the parotid gland, followed by the submandibular and sublingual glands. Western blot analysis revealed DAT, VMAT-1, VMAT-2, and dopamine receptors immunoreactivity in membrane preparations obtained from the three glands investigated. Immunostaining for dopamine and transporters was developed within striated ducts. Salivary glands processed for dopamine receptors immunohistochemistry developed an immunoreaction primarily in striated and excretory ducts. In the submandibular gland, acinar cells displayed strong immunoreactivity for the D2 receptor, while cells of the convoluted granular tubules were negative for both D1-like and D2-like receptors. Parotid glands acinar cells displayed the highest immunoreactivity for both D1 and D2 receptors compared with other salivary glands. The above localization of dopamine and dopaminergic markers investigated did not correspond closely with neuron-specific enolase (NSE) localization. This indicates that at least in part, catecholamine stores and dopaminergic markers are independent from glandular innervation. These findings suggest that rat major salivary glands express a dopaminergic system probably involved in salivary secretion. The stronger immunoreactivity for dopamine transporters and receptors in striated duct cells suggests that the dopaminergic system could regulate not only quality, but also volume and ionic concentration of saliva. Copyright © 2015 the American Physiological Society.

  15. Highly Attenuated Recombinant Vesicular Stomatitis Virus VSV-12′GFP Displays Immunogenic and Oncolytic Activity

    Science.gov (United States)

    Davis, John N.

    2013-01-01

    Vesicular stomatitis virus (VSV) has shown considerable promise both as an immunization vector and as an oncolytic virus. In both applications, an important concern is the safety profile of the virus. To generate a highly attenuated virus, we added two reporter genes to the 3′ end of the VSV genome, thereby shifting the NPMGL genes from positions 1 to 5 to positions 3 to 7. The resulting virus (VSV-12′GFP) was highly attenuated, generating smaller plaques than four other attenuated VSVs. In one-step growth curves, VSV-12′GFP displayed the slowest growth kinetics. The mechanism of attenuation appears to be due to reduced expression of VSV genes downstream of the reporter genes, as suggested by a 10.4-fold reduction in L-protein RNA transcript. Although attenuated, VSV-12′GFP was highly effective at generating an immune response, indicated by a high-titer antibody response against the green fluorescent protein (GFP) expressed by the virus. Although VSV-12′GFP was more attenuated than other VSVs on both normal and cancer cells, it nonetheless showed a greater level of infection of human cancer cells (glioma and melanoma) than of normal cells, and this effect was magnified in glioma by interferon application, indicating selective oncolysis. Intravenous VSV-12′GFP selectively infected human gliomas implanted into SCID mice subcutaneously or intracranially. All postnatal day 16 mice given intranasal VSV-12′GFP survived, whereas only 10% of those given VSV-G/GFP survived, indicating reduced neurotoxicity. Intratumoral injection of tumors with VSV-12′GFP dramatically suppressed tumor growth and enhanced survival. Together these data suggest this recombinant virus merits further study for its oncolytic and vaccine potential. PMID:23135719

  16. In Vitro and In Vivo Attenuation of Vesicular Stomatitis Virus (VSV) by Phosphoprotein Deletion.

    Science.gov (United States)

    Wongthida, Phonphimon; Jengarn, Juggragarn; Narkpuk, Jaraspim; Koonyosying, Pongpisid; Srisutthisamphan, Kanjana; Wanitchang, Asawin; Leaungwutiwong, Pornsawan; Teeravechyan, Samaporn; Jongkaewwattana, Anan

    2016-01-01

    Vesicular stomatitis virus (VSV) is highly immunogenic and able to stimulate both innate and adaptive immune responses. However, its ability to induce adverse effects has held back the use of VSV as a potential vaccine vector. In this study we developed VSV-ΔP, a safe yet potent replication-defective recombinant VSV in which the phosphoprotein (P) gene was deleted. VSV-ΔP replicated only in supporting cells expressing P (BHK-P cells) and at levels more than 2 logs lower than VSV. In vivo studies indicated that the moderate replication of VSV-ΔP in vitro was associated with the attenuation of this virus in the mouse model, whereas mice intracranially injected with VSV succumbed to neurotoxicity. Furthermore, we constructed VSV and VSV-ΔP expressing a variety of antigens including hemagglutinin-neuraminidase (HN) from Newcastle disease virus (NDV), hemagglutinin (HA) from either a 2009 H1N1 pandemic influenza virus (pdm/09) or the avian H7N9. VSV and VSV-ΔP incorporated the foreign antigens on their surface resulting in induction of robust neutralizing antibody, serum IgG, and hemagglutination inhibition (HAI) titers against their corresponding viruses. These results indicated that VSV with P gene deletion was attenuated in vitro and in vivo, and possibly expressed the foreign antigen on its surface. Therefore, the P gene-deletion strategy may offer a potentially useful and safer approach for attenuating negative-sense RNA viruses which use phosphoprotein as a cofactor for viral replication.

  17. Enhanced immunosurveillance for animal morbilliviruses using vesicular stomatitis virus (VSV) pseudotypes.

    Science.gov (United States)

    Logan, Nicola; Dundon, William G; Diallo, Adama; Baron, Michael D; James Nyarobi, M; Cleaveland, Sarah; Keyyu, Julius; Fyumagwa, Robert; Hosie, Margaret J; Willett, Brian J

    2016-11-11

    The measurement of virus-specific neutralising antibodies represents the "gold-standard" for diagnostic serology. For animal morbilliviruses, such as peste des petits ruminants (PPRV) or rinderpest virus (RPV), live virus-based neutralisation tests require high-level biocontainment to prevent the accidental escape of the infectious agents. In this study, we describe the adaptation of a replication-defective vesicular stomatitis virus (VSVΔG) based pseudotyping system for the measurement of neutralising antibodies against animal morbilliviruses. By expressing the haemagglutinin (H) and fusion (F) proteins of PPRV on VSVΔG pseudotypes bearing a luciferase marker gene, neutralising antibody titres could be measured rapidly and with high sensitivity. Serological responses against the four distinct lineages of PPRV could be measured simultaneously and cross-neutralising responses against other morbilliviruses compared. Using this approach, we observed that titres of neutralising antibodies induced by vaccination with live attenuated PPRV were lower than those induced by wild type virus infection and the level of cross-lineage neutralisation varied between vaccinates. By comparing neutralising responses from animals infected with either PPRV or RPV, we found that responses were highest against the homologous virus, indicating that retrospective analyses of serum samples could be used to confirm the nature of the original pathogen to which an animal had been exposed. Accordingly, when screening sera from domestic livestock and wild ruminants in Tanzania, we detected evidence of cross-species infection with PPRV, canine distemper virus (CDV) and a RPV-related bovine morbillivirus, suggesting that exposure to animal morbilliviruses may be more widespread than indicated previously using existing diagnostic techniques. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Molecular Determinants of Susceptibility to Oncolytic Vesicular Stomatitis Virus in Pancreatic Adenocarcinoma

    Science.gov (United States)

    Blackham, Aaron U; Northrup, Scott A; Willingham, Mark; Sirintrapun, Joseph; Russell, Greg B; Lyles, Douglas S; Stewart, John H

    2014-01-01

    Background M protein mutant vesicular stomatitis virus (M51R-VSV) has oncolytic properties against many cancers. However, some cancer cells are resistant to M51R-VSV. Herein, we evaluate the molecular determinants of VSV resistance in pancreatic adenocarcinoma cells. Methods Cell viability and the effect of β-interferon (IFN) was analyzed using MTS assay. Gene expression was evaluated via microarray analysis. Cell infectability was measured by flow cytometry. Xenografts were established in athymic nude mice and treated with intratumoral M51R-VSV. Results Four of five pancreatic cancer cell lines were sensitive to M51R-VSV, while Panc03.27 cells remained resistant (81±3% viability 72-hours after single cycle infection). Comparing sensitive MiaPaCa2 to resistant Panc03.27 cells, significant differences in gene expression was found relating to IFN signaling (p=2×10-5), viral entry (p=3×10-4) and endocytosis (p=7×10-4). MiaPaCa2 cells permitted high levels of VSV infection, while Panc03.27 cells were capable of resisting VSV cell entry even at high MOIs. Extrinsic β-IFN overcame apparent defects in IFN-mediated pathways in MiaPaCa2 cells conferring VSV resistance. In contrast, β-IFN decreased cell viability in Panc3.27 cells suggesting intact anti-viral mechanisms. VSV treated xenografts exhibited reduced tumor growth relative to controls in both MiaPaCa2 (1423 ± 345% vs 164 ± 136%, pVSV treated Panc03.27 xenografts. Conclusions Inhibition of VSV endocytosis and intact IFN-mediated defenses are responsible for M51R-VSV resistance in pancreatic adenocarcinoma cells. M51R-VSV treatment appears to induce anti-tumor cellular immunity in vivo which may expand its clinical efficacy. PMID:24252853

  19. Highly attenuated recombinant vesicular stomatitis virus VSV-12'GFP displays immunogenic and oncolytic activity.

    Science.gov (United States)

    van den Pol, Anthony N; Davis, John N

    2013-01-01

    Vesicular stomatitis virus (VSV) has shown considerable promise both as an immunization vector and as an oncolytic virus. In both applications, an important concern is the safety profile of the virus. To generate a highly attenuated virus, we added two reporter genes to the 3' end of the VSV genome, thereby shifting the NPMGL genes from positions 1 to 5 to positions 3 to 7. The resulting virus (VSV-12'GFP) was highly attenuated, generating smaller plaques than four other attenuated VSVs. In one-step growth curves, VSV-12'GFP displayed the slowest growth kinetics. The mechanism of attenuation appears to be due to reduced expression of VSV genes downstream of the reporter genes, as suggested by a 10.4-fold reduction in L-protein RNA transcript. Although attenuated, VSV-12'GFP was highly effective at generating an immune response, indicated by a high-titer antibody response against the green fluorescent protein (GFP) expressed by the virus. Although VSV-12'GFP was more attenuated than other VSVs on both normal and cancer cells, it nonetheless showed a greater level of infection of human cancer cells (glioma and melanoma) than of normal cells, and this effect was magnified in glioma by interferon application, indicating selective oncolysis. Intravenous VSV-12'GFP selectively infected human gliomas implanted into SCID mice subcutaneously or intracranially. All postnatal day 16 mice given intranasal VSV-12'GFP survived, whereas only 10% of those given VSV-G/GFP survived, indicating reduced neurotoxicity. Intratumoral injection of tumors with VSV-12'GFP dramatically suppressed tumor growth and enhanced survival. Together these data suggest this recombinant virus merits further study for its oncolytic and vaccine potential.

  20. In Vitro and In Vivo Attenuation of Vesicular Stomatitis Virus (VSV by Phosphoprotein Deletion.

    Directory of Open Access Journals (Sweden)

    Phonphimon Wongthida

    Full Text Available Vesicular stomatitis virus (VSV is highly immunogenic and able to stimulate both innate and adaptive immune responses. However, its ability to induce adverse effects has held back the use of VSV as a potential vaccine vector. In this study we developed VSV-ΔP, a safe yet potent replication-defective recombinant VSV in which the phosphoprotein (P gene was deleted. VSV-ΔP replicated only in supporting cells expressing P (BHK-P cells and at levels more than 2 logs lower than VSV. In vivo studies indicated that the moderate replication of VSV-ΔP in vitro was associated with the attenuation of this virus in the mouse model, whereas mice intracranially injected with VSV succumbed to neurotoxicity. Furthermore, we constructed VSV and VSV-ΔP expressing a variety of antigens including hemagglutinin-neuraminidase (HN from Newcastle disease virus (NDV, hemagglutinin (HA from either a 2009 H1N1 pandemic influenza virus (pdm/09 or the avian H7N9. VSV and VSV-ΔP incorporated the foreign antigens on their surface resulting in induction of robust neutralizing antibody, serum IgG, and hemagglutination inhibition (HAI titers against their corresponding viruses. These results indicated that VSV with P gene deletion was attenuated in vitro and in vivo, and possibly expressed the foreign antigen on its surface. Therefore, the P gene-deletion strategy may offer a potentially useful and safer approach for attenuating negative-sense RNA viruses which use phosphoprotein as a cofactor for viral replication.

  1. Glycoprotein cytoplasmic domain sequences required for rescue of a vesicular stomatitis virus glycoprotein mutant

    Energy Technology Data Exchange (ETDEWEB)

    Whitt, M.A.; Chong, L.; Rose, J.K. (Yale Univ. School of Medicine, New Haven, CT (USA))

    1989-09-01

    The authors have used transient expression of the wild-type vesicular stomatitis virus (VSV) glycoprotein (G protein) from cloned cDNA to rescue a temperature-sensitive G protein mutant of VSV in cells at the nonpermissive temperature. Using cDNAs encoding G proteins with deletions in the normal 29-amino-acid cytoplasmic domain, they determined that the presence of either the membrane-proximal 9 amino acids or the membrane-distal 12 amino acids was sufficient for rescue of the temperature-sensitive mutant. G proteins with cytoplasmic domains derived from other cellular or viral G proteins did not rescue the mutant, nor did G proteins with one or three amino acids of the normal cytoplasmic domain. Rescue correlated directly with the ability of the G proteins to be incorporated into virus particles. This was shown by analysis of radiolabeled particles separated on sucrose gradients as well as by electron microscopy of rescued virus after immunogold labeling. Quantitation of surface expression showed that all of the mutated G proteins were expressed less efficiently on the cell surface than was wild-type G protein. However, they were able to correct for differences in rescue efficiency resulting from differences in the level of surface expression by reducing wild-type G protein expression to levels equivalent to those observed for the mutated G proteins. The results provide evidence that at least a portion of the cytoplasmic domain is required for efficient assembly of the VSV G protein into virions during virus budding.

  2. Mutations in the glycoprotein of vesicular stomatitis virus affect cytopathogenicity: potential for oncolytic virotherapy.

    Science.gov (United States)

    Janelle, Valérie; Brassard, Frédérick; Lapierre, Pascal; Lamarre, Alain; Poliquin, Laurent

    2011-07-01

    Vesicular stomatitis virus (VSV) has been widely used to characterize cellular processes, viral resistance, and cytopathogenicity. Recently, VSV has also been used for oncolytic virotherapy due to its capacity to selectively lyse tumor cells. Mutants of the matrix (M) protein of VSV have generally been preferred to the wild-type virus for oncolysis because of their ability to induce type I interferon (IFN) despite causing weaker cytopathic effects. However, due to the large variability of tumor types, it is quite clear that various approaches and combinations of multiple oncolytic viruses will be needed to effectively treat most cancers. With this in mind, our work focused on characterizing the cytopathogenic profiles of four replicative envelope glycoprotein (G) VSV mutants. In contrast to the prototypic M mutant, VSV G mutants are as efficient as wild-type virus at inhibiting cellular transcription and host protein translation. Despite being highly cytopathic, the mutant G(6R) triggers type I interferon secretion as efficiently as the M mutant. Importantly, most VSV G mutants are more effective at killing B16 and MC57 tumor cells in vitro than the M mutant or wild-type virus through apoptosis induction. Taken together, our results demonstrate that VSV G mutants retain the high cytopathogenicity of wild-type VSV, with G(6R) inducing type I IFN secretion at levels similar to that of the M mutant. VSV G protein mutants could therefore prove to be highly valuable for the development of novel oncolytic virotherapy strategies that are both safe and efficient for the treatment of various types of cancer.

  3. Resistance of pancreatic cancer cells to oncolytic vesicular stomatitis virus: role of type I interferon signaling.

    Science.gov (United States)

    Moerdyk-Schauwecker, Megan; Shah, Nirav R; Murphy, Andrea M; Hastie, Eric; Mukherjee, Pinku; Grdzelishvili, Valery Z

    2013-02-05

    Oncolytic virus (OV) therapy takes advantage of common cancer characteristics, such as defective type I interferon (IFN) signaling, to preferentially infect and kill cancer cells with viruses. Our recent study (Murphy et al., 2012. J. Virol. 86, 3073-87) found human pancreatic ductal adenocarcinoma (PDA) cells were highly heterogeneous in their permissiveness to vesicular stomatitis virus (VSV) and suggested at least some resistant cell lines retained functional type I IFN responses. Here we examine cellular responses to infection by the oncolytic VSV recombinant VSV-ΔM51-GFP by analyzing a panel of 11 human PDA cell lines for expression of 33 genes associated with type I IFN pathways. Although all cell lines sensed infection by VSV-ΔM51-GFP and most activated IFN-α and β expression, only resistant cell lines displayed constitutive high-level expression of the IFN-stimulated antiviral genes MxA and OAS. Inhibition of JAK/STAT signaling decreased levels of MxA and OAS and increased VSV infection, replication and oncolysis, further implicating IFN responses in resistance. Unlike VSV, vaccinia and herpes simplex virus infectivity and killing of PDA cells was independent of the type I IFN signaling profile, possibly because these two viruses are better equipped to evade type I IFN responses. Our study demonstrates heterogeneity in the type I IFN signaling status of PDA cells and suggests MxA and OAS as potential biomarkers for PDA resistance to VSV and other OVs sensitive to type I IFN responses. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Interation of mRNA with proteins in vesicular stomatitis virus-infected cells

    Energy Technology Data Exchange (ETDEWEB)

    Adam, S.A.; Choi, Y.D.; Dreyfuss, G.

    1986-02-01

    The interaction of mRNA with proteins in vesicular stomatitis virus (VSV)-infected cells was studied by photochemical cross-linking in intact cells. The major (/sup 35/S)methionine-labeled proteins which became cross-linked by UV light to mRNA in uninfected and in VSV-infected HeLa cells were similar and had apparent mobilities in sodium dodecyl sulfate-polyacrylamide gel electrophoresis corresponding to 135, 93, 72, 68, 53, 50, 43, and 36 kilodaltons. The proteins which were cross-linked in vivo specifically to the five mRNAs of VSV were labeled through radioactive nucleotides incorporated only into VSV mRNAs under conditions in which only VSV mRNAs are labeled. The same major mRNP proteins that became cross-linked to host mRNAs also became cross-linked to VSV mRNAs, although several quantitative differences were detected. Photochemical cross-linking and immunoblotting of cross-linked mRNPs with VSV antiserum demonstrated that in addition to host proteins VSV mRNAs also became cross-linked to the VSV-encoded N protein. The poly(A) segment of both host and VSV mRNAs was associated in vivo selectively with the 72-kilodalton polypeptide. The major proteins of mRNA-ribonucleoprotein complexes are therefore ubiquitous and common to different mRNAs. Furthermore, since the major messenger ribonucleoproteins interact also with VSV mRNAs even though these mRNAs are transcribed in the cytoplasm, it appears that nuclear transcription and nucleocytoplasmic transport are not necessary for mRNA to interact with these proteins.

  5. Cellular proteins associated with the interior and exterior of vesicular stomatitis virus virions.

    Science.gov (United States)

    Moerdyk-Schauwecker, Megan; Hwang, Sun-Il; Grdzelishvili, Valery Z

    2014-01-01

    Virus particles (virions) often contain not only virus-encoded but also host-encoded proteins. Some of these host proteins are enclosed within the virion structure, while others, in the case of enveloped viruses, are embedded in the host-derived membrane. While many of these host protein incorporations are likely accidental, some may play a role in virus infectivity, replication and/or immunoreactivity in the next host. Host protein incorporations may be especially important in therapeutic applications where large numbers of virus particles are administered. Vesicular stomatitis virus (VSV) is the prototypic rhabdovirus and a candidate vaccine, gene therapy and oncolytic vector. Using mass spectrometry, we previously examined cell type dependent host protein content of VSV virions using intact ("whole") virions purified from three cell lines originating from different species. Here we aimed to determine the localization of host proteins within the VSV virions by analyzing: i) whole VSV virions; and ii) whole VSV virions treated with Proteinase K to remove all proteins outside the viral envelope. A total of 257 proteins were identified, with 181 identified in whole virions and 183 identified in Proteinase K treated virions. Most of these proteins have not been previously shown to be associated with VSV. Functional enrichment analysis indicated the most overrepresented categories were proteins associated with vesicles, vesicle-mediated transport and protein localization. Using western blotting, the presence of several host proteins, including some not previously shown in association with VSV (such as Yes1, Prl1 and Ddx3y), was confirmed and their relative quantities in various virion fractions determined. Our study provides a valuable inventory of virion-associated host proteins for further investigation of their roles in the replication cycle, pathogenesis and immunoreactivity of VSV.

  6. Type III interferon attenuates a vesicular stomatitis virus-based vaccine vector.

    Science.gov (United States)

    Guayasamin, Ryann C; Reynolds, Tracy D; Wei, Xin; Fujiwara, Mai; Robek, Michael D

    2014-09-01

    Vesicular stomatitis virus (VSV) has been extensively studied as a vaccine vector and oncolytic agent. Nevertheless, safety concerns have limited its widespread use in humans. The type III lambda interferon (IFN-λ) family of cytokines shares common signaling pathways with the IFN-α/β family and thus evokes similar antiviral activities. However, IFN-λ signals through a distinct receptor complex that is expressed in a cell type-specific manner, which restricts its activity to epithelial barriers, particularly those corresponding to the respiratory and gastrointestinal tracts. In this study, we determined how IFN-λ expression from recombinant VSV would influence vector replication, spread, and immunogenicity. We demonstrate that IFN-λ expression severely attenuates VSV in cell culture. In vivo, IFN-λ limits VSV replication in the mouse lung after intranasal administration and reduces virus spread to other organs. Despite this attenuation, however, the vector retains its capacity to induce protective CD8 T cell and antibody responses after a single immunization. These findings demonstrate a novel method of viral vector attenuation that could be used in both vaccine and oncolytic virus applications. Viruses such as VSV that are used as vaccine vectors can induce protective T cell and antibody responses after a single dose. Additionally, IFN-λ is a potent antiviral agent that has certain advantages for clinical use compared to IFN-α/β, such as fewer patient side effects. Here, we demonstrate that IFN-λ attenuates VSV replication and spread following intranasal virus delivery but does not reduce the ability of VSV to induce potent protective immune responses. These findings demonstrate that the type III IFN family may have widespread applicability for improving the safety and efficacy of viral vaccine and oncolytic vectors. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Induction of Stress Granule-Like Structures in Vesicular Stomatitis Virus-Infected Cells

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    Dinh, Phat X.; Beura, Lalit K.; Das, Phani B.; Panda, Debasis; Das, Anshuman

    2013-01-01

    Previous studies from our laboratory revealed that cellular poly(C) binding protein 2 (PCBP2) downregulates vesicular stomatitis virus (VSV) gene expression. We show here that VSV infection induces the formation of granular structures in the cytoplasm containing cellular RNA-binding proteins, including PCBP2, T-cell-restricted intracellular antigen 1 (TIA1), and TIA1-related protein (TIAR). Depletion of TIA1 via small interfering RNAs (siRNAs), but not depletion of TIAR, results in enhanced VSV growth and gene expression. The VSV-induced granules appear to be similar to the stress granules (SGs) generated in cells triggered by heat shock or oxidative stress but do not contain some of the bona fide SG markers, such as eukaryotic initiation factor 3 (eIF3) or eIF4A, or the processing body (PB) markers, such as mRNA-decapping enzyme 1A (DCP1a), and thus may not represent canonical SGs or PBs. Our results revealed that the VSV-induced granules, called SG-like structures here, contain the viral replicative proteins and RNAs. The formation and maintenance of the SG-like structures required viral replication and ongoing protein synthesis, but an intact cytoskeletal network was not necessary. These results suggest that cells respond to VSV infection by aggregating the antiviral proteins, such as PCBP2 and TIA1, to form SG-like structures. The functional significance of these SG-like structures in VSV-infected cells is currently under investigation. PMID:23077311

  8. Antagonistic Effects of Cellular Poly(C) Binding Proteins on Vesicular Stomatitis Virus Gene Expression ▿

    Science.gov (United States)

    Dinh, Phat X.; Beura, Lalit K.; Panda, Debasis; Das, Anshuman; Pattnaik, Asit K.

    2011-01-01

    Immunoprecipitation and subsequent mass spectrometry analysis of the cellular proteins from cells expressing the vesicular stomatitis virus (VSV) P protein identified the poly(C) binding protein 2 (PCBP2) as one of the P protein-interacting proteins. To investigate the role of PCBP2 in the viral life cycle, we examined the effects of depletion or overexpression of this protein on VSV growth. Small interfering RNA-mediated silencing of PCBP2 promoted VSV replication. Conversely, overexpression of PCBP2 in transfected cells suppressed VSV growth. Further studies revealed that PCBP2 negatively regulates overall viral mRNA accumulation and subsequent genome replication. Coimmunoprecipitation and immunofluorescence microscopic studies showed that PCBP2 interacts and colocalizes with VSV P protein in virus-infected cells. The P-PCBP2 interaction did not result in reduced levels of protein complex formation with the viral N and L proteins, nor did it induce degradation of the P protein. In addition, PCBP1, another member of the poly(C) binding protein family with homology to PCBP2, was also found to interact with the P protein and inhibit the viral mRNA synthesis at the level of primary transcription without affecting secondary transcription or genome replication. The inhibitory effects of PCBP1 on VSV replication were less pronounced than those of PCBP2. Overall, the results presented here suggest that cellular PCBP2 and PCBP1 antagonize VSV growth by affecting viral gene expression and highlight the importance of these two cellular proteins in restricting virus infections. PMID:21752917

  9. Cellular proteins associated with the interior and exterior of vesicular stomatitis virus virions.

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    Megan Moerdyk-Schauwecker

    Full Text Available Virus particles (virions often contain not only virus-encoded but also host-encoded proteins. Some of these host proteins are enclosed within the virion structure, while others, in the case of enveloped viruses, are embedded in the host-derived membrane. While many of these host protein incorporations are likely accidental, some may play a role in virus infectivity, replication and/or immunoreactivity in the next host. Host protein incorporations may be especially important in therapeutic applications where large numbers of virus particles are administered. Vesicular stomatitis virus (VSV is the prototypic rhabdovirus and a candidate vaccine, gene therapy and oncolytic vector. Using mass spectrometry, we previously examined cell type dependent host protein content of VSV virions using intact ("whole" virions purified from three cell lines originating from different species. Here we aimed to determine the localization of host proteins within the VSV virions by analyzing: i whole VSV virions; and ii whole VSV virions treated with Proteinase K to remove all proteins outside the viral envelope. A total of 257 proteins were identified, with 181 identified in whole virions and 183 identified in Proteinase K treated virions. Most of these proteins have not been previously shown to be associated with VSV. Functional enrichment analysis indicated the most overrepresented categories were proteins associated with vesicles, vesicle-mediated transport and protein localization. Using western blotting, the presence of several host proteins, including some not previously shown in association with VSV (such as Yes1, Prl1 and Ddx3y, was confirmed and their relative quantities in various virion fractions determined. Our study provides a valuable inventory of virion-associated host proteins for further investigation of their roles in the replication cycle, pathogenesis and immunoreactivity of VSV.

  10. Interference of CD40L-mediated tumor immunotherapy by oncolytic vesicular stomatitis virus.

    Science.gov (United States)

    Galivo, Feorillo; Diaz, Rosa Maria; Thanarajasingam, Uma; Jevremovic, Dragan; Wongthida, Phonphimon; Thompson, Jill; Kottke, Timothy; Barber, Glen N; Melcher, Alan; Vile, Richard G

    2010-04-01

    Oncolytic virotherapy can be achieved in two ways: (1) by exploiting an innate ability of certain viruses to selectively replicate in tumor tissues, and (2) by using viruses to deliver toxic or immunostimulatory genes to tumors. Vesicular stomatitis virus (VSV) selectively replicates in tumors lacking adequate type I interferon response. The efficacy of oncolytic virotherapy using VSV against B16 melanomas in C57BL/6 mice is dependent on CD8(+) T and natural killer cells. Because immunotherapies that prime specific CD8(+) T cells against melanocyte/melanoma antigens can generate significant therapeutic responses, we hypothesized that engineering VSV to express the potent T cell costimulatory molecule CD40 ligand (VSV-CD40L) would enhance virotherapy with concomitant priming of melanoma-specific T cells. However, we observed no difference in antitumor efficacy between the parental VSV-GFP and VSV-CD40L. In contrast, intratumoral injection of a replication-defective adenovirus expressing CD40L (Ad-CD40L) consistently produced significantly greater therapy than either replication-competent VSV-GFP or VSV-CD40L. The Ad-CD40L-mediated tumor regressions were associated with specific T cell responses against tumor-associated antigens (TAAs), which took several days to develop, whereas VSV-CD40L rapidly induced high levels of T cell activation without specificity for TAAs. These data suggest that the high levels of VSV-associated immunogenicity distracted immune responses away from priming of tumor-specific T cells, even in the presence of potent costimulatory signals. In contrast, a replication-defective Ad-CD40L allowed significant priming of T cells directed against TAAs. These observations suggest that an efficiently primed antitumor T cell response can produce similar, if not better, therapy against an established melanoma compared with intratumoral injection of a replication-competent oncolytic virus.

  11. Characteristics of oncolytic vesicular stomatitis virus displaying tumor-targeting ligands.

    Science.gov (United States)

    Ammayappan, Arun; Peng, Kah-Whye; Russell, Stephen J

    2013-12-01

    We sought proof of principle that tumor-targeting ligands can be displayed on the surface of vesicular stomatitis virus (VSV) by engineering its glycoprotein. Here, we successfully rescued VSVs displaying tumor vasculature-targeting ligands. By using a rational approach, we investigated various feasible insertion sites on the G protein of VSV (VSV-G) for display of tumor vasculature-targeting ligands, cyclic RGD (cRGD) and echistatin. We found seven sites on VSV-G that tolerated insertion of the 9-residue cRGD peptide, two of which could tolerate insertion of the 49-amino acid echistatin domain. All of the ligand-displaying viruses replicated as well as the parental virus. In vitro studies demonstrated that the VSV-echistatin viruses specifically bound to targeted integrins. Since the low-density lipoprotein receptor (LDLR) was recently identified as a major receptor for VSV, we investigated the entry of ligand-displaying viruses after masking LDLR. The experiment showed that the modified viruses can enter the cell independently of LDLR, whereas entry of unmodified virus is significantly blocked by a specific monoclonal antibody against LDLR. Both parental and ligand-displaying viruses displayed equal oncolytic efficacies in a syngeneic mouse myeloma model. We further demonstrated that single-chain antibody fragments against tumor-specific antigens can be inserted at the N terminus of the G protein and that corresponding replication-competent VSVs can be rescued efficiently. Overall, we demonstrated that functional tumor-targeting ligands can be displayed on replication-competent VSVs without perturbing viral growth and oncolytic efficacy. This study provides a rational foundation for the future development of fully retargeted oncolytic VSVs.

  12. Vesicular stomatitis virus-based ebola vaccine is well-tolerated and protects immunocompromised nonhuman primates.

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    Thomas W Geisbert

    2008-11-01

    Full Text Available Ebola virus (EBOV is a significant human pathogen that presents a public health concern as an emerging/re-emerging virus and as a potential biological weapon. Substantial progress has been made over the last decade in developing candidate preventive vaccines that can protect nonhuman primates against EBOV. Among these prospects, a vaccine based on recombinant vesicular stomatitis virus (VSV is particularly robust, as it can also confer protection when administered as a postexposure treatment. A concern that has been raised regarding the replication-competent VSV vectors that express EBOV glycoproteins is how these vectors would be tolerated by individuals with altered or compromised immune systems such as patients infected with HIV. This is especially important as all EBOV outbreaks to date have occurred in areas of Central and Western Africa with high HIV incidence rates in the population. In order to address this concern, we evaluated the safety of the recombinant VSV vector expressing the Zaire ebolavirus glycoprotein (VSVDeltaG/ZEBOVGP in six rhesus macaques infected with simian-human immunodeficiency virus (SHIV. All six animals showed no evidence of illness associated with the VSVDeltaG/ZEBOVGP vaccine, suggesting that this vaccine may be safe in immunocompromised populations. While one goal of the study was to evaluate the safety of the candidate vaccine platform, it was also of interest to determine if altered immune status would affect vaccine efficacy. The vaccine protected 4 of 6 SHIV-infected macaques from death following ZEBOV challenge. Evaluation of CD4+ T cells in all animals showed that the animals that succumbed to lethal ZEBOV challenge had the lowest CD4+ counts, suggesting that CD4+ T cells may play a role in mediating protection against ZEBOV.

  13. Comparative oncology evaluation of intravenous recombinant oncolytic Vesicular Stomatitis Virus therapy in spontaneous canine cancer.

    Science.gov (United States)

    Naik, Shruthi; Galyon, Gina D; Jenks, Nathan J; Steele, Michael B; Miller, Amber C; Allstadt, Sara D; Suksanpaisan, Lukkana; Peng, Kah Whye; Federspiel, Mark J; Russell, Stephen J; LeBlanc, Amy K

    2017-11-20

    Clinical translation of intravenous therapies to treat disseminated or metastatic cancer is imperative. Comparative oncology, the evaluation of novel cancer therapies in animals with spontaneous cancer, can be utilized to inform and accelerate clinical translation. Preclinical murine studies demonstrate that single shot systemic therapy with a VSV-IFNβ-NIS, a novel recombinant oncolytic Vesicular stomatitis virus (VSV), can induce curative remission in tumor bearing mice. Clinical translation of VSV-IFNβ-NIS therapy is dependent on comprehensive assessment of clinical toxicities, virus shedding, pharmacokinetics, and efficacy in clinically relevant models. Dogs spontaneously develop cancer with comparable etiology, clinical progression and response to therapy as human malignancies. A comparative oncology study was carried out to investigate feasibility and tolerability of intravenous oncolytic VSV-IFNβ-NIS therapy in pet dogs with spontaneous cancer. Nine dogs with various malignancies were treated with a single intravenous dose of VSV-IFNβ-NIS. Two dogs with high-grade peripheral T-cell lymphoma had rapid but transient remission of disseminated disease and transient hepatotoxicity that resolved spontaneously. There was no shedding of infectious virus. Correlative pharmacokinetic studies revealed elevated levels of VSV RNA in blood in dogs with measurable disease remission. This is the first evaluation of intravenous oncolytic virus therapy for spontaneous canine cancer, demonstrating that VSV-IFNβ-NIS is well-tolerated and safe in dogs with advanced or metastatic disease. This approach has informed clinical translation, including dose and target indication selection, leading to a clinical investigation of intravenous VSV-IFNβ-NIS therapy, and provided preliminary evidence of clinical efficacy, and potential biomarkers that correlate with therapeutic response. Copyright ©2017, American Association for Cancer Research.

  14. Modulation of gastrin processing by vesicular monoamine transporter type 1 (VMAT1) in rat gastrin cells

    Science.gov (United States)

    Hussain, I; Bate, G W; Henry, J; Djali, P; Dimaline, R; Dockray, G J; Varro, A

    1999-01-01

    Gastrointestinal endocrine cells produce biogenic amines which are transported into secretory vesicles by one of two proton-amine exchangers, vesicular monoamine transporters type 1 and 2 (VMAT1 and 2). We report here the presence of VMAT1 in rat gastrin (G) cells and the relevance of VMAT1 function for the modulation of progastrin processing by biogenic and dietary amines. In immunocytochemical studies VMAT1, but not VMAT2, was localized to subpopulations of G cells and enterochromaffin (EC) cells; neither was found in antral D cells. The expression of VMAT1 in antral mucosa was confirmed by Northern blot analysis, which revealed an mRNA band of approximately 3.2 kb, and by Western blot analysis, which revealed a major protein of 55 kDa. In pulse-chase labelling experiments, the conversion of the amidated gastrin G34 to G17 was inhibited by biogenic amine precursors (L-DOPA and 5-hydroxytryptophan). This inhibition was stereospecific and sensitive to reserpine (50 nM), which blocks VMAT1 and VMAT2, but resistant to tetrabenazine, which is a selective inhibitor of VMAT2. Dietary amines such as tyramine and tryptamine also inhibited G34 cleavage. This effect was associated with a loss of the electron-dense core of G cell secretory vesicles. It was not stereospecific or reserpine sensitive, but was correlated with hydrophobicity. Thus rat antral G cells can express VMAT1; transport of biogenic amines into secretory vesicles by VMAT1 is associated with inhibition of G34 cleavage, perhaps by raising intravesicular pH. Dietary amines also modulate cleavage of progastrin-derived peptides, but do so by a VMAT1-independent mechanism; they may act as weak bases that passively permeate secretory vesicle membranes and raise intravesicular pH. PMID:10332097

  15. Semireplication-competent vesicular stomatitis virus as a novel platform for oncolytic virotherapy.

    Science.gov (United States)

    Muik, Alexander; Dold, Catherine; Geiß, Yvonne; Volk, Andreas; Werbizki, Marina; Dietrich, Ursula; von Laer, Dorothee

    2012-08-01

    Among oncolytic viruses, the vesicular stomatitis virus (VSV) is especially potent and a highly promising agent for the treatment of cancer. But, even though effective against multiple tumor entities in preclinical animal models, replication-competent VSV exhibits inherent neurovirulence, which has so far hindered clinical development. To overcome this limitation, replication-defective VSV vectors for cancer gene therapy have been tested and proven to be safe. However, gene delivery was inefficient and only minor antitumor efficacy was observed. Here, we present semireplication-competent vector systems for VSV (srVSV), composed of two trans-complementing, propagation-deficient VSV vectors. The de novo generated deletion mutants of the two VSV polymerase proteins P (phosphoprotein) and L (large catalytic subunit), VSVΔP and VSVΔL respectively, were used mutually or in combination with VSVΔG vectors. These srVSV systems copropagated in vitro and in vivo without recombinatory reversion to replication-competent virus. The srVSV systems were highly lytic for human glioblastoma cell lines, spheroids, and subcutaneous xenografts. Especially the combination of VSVΔG/VSVΔL vectors was as potent as wild-type VSV (VSV-WT) in vitro and induced long-term tumor regression in vivo without any associated adverse effects. In contrast, 90% of VSV-WT-treated animals succumbed to neurological disease shortly after tumor clearance. Most importantly, even when injected into the brain, VSVΔG/VSVΔL did not show any neurotoxicity. In conclusion, srVSV is a promising platform for virotherapeutic approaches and also for VSV-based vector vaccines, combining improved safety with an increased coding capacity for therapeutic transgenes, potentially allowing for multipronged approaches.

  16. Current good manufacturing practice production of an oncolytic recombinant vesicular stomatitis viral vector for cancer treatment.

    Science.gov (United States)

    Ausubel, L J; Meseck, M; Derecho, I; Lopez, P; Knoblauch, C; McMahon, R; Anderson, J; Dunphy, N; Quezada, V; Khan, R; Huang, P; Dang, W; Luo, M; Hsu, D; Woo, S L C; Couture, L

    2011-04-01

    Vesicular stomatitis virus (VSV) is an oncolytic virus currently being investigated as a promising tool to treat cancer because of its ability to selectively replicate in cancer cells. To enhance the oncolytic property of the nonpathologic laboratory strain of VSV, we generated a recombinant vector [rVSV(MΔ51)-M3] expressing murine gammaherpesvirus M3, a secreted viral chemokine-binding protein that binds to a broad range of mammalian chemokines with high affinity. As previously reported, when rVSV(MΔ51)-M3 was used in an orthotopic model of hepatocellular carcinoma (HCC) in rats, it suppressed inflammatory cell migration to the virus-infected tumor site, which allowed for enhanced intratumoral virus replication leading to increased tumor necrosis and substantially prolonged survival. These encouraging results led to the development of this vector for clinical translation in patients with HCC. However, a scalable current Good Manufacturing Practice (cGMP)-compliant manufacturing process has not been described for this vector. To produce the quantities of high-titer virus required for clinical trials, a process that is amenable to GMP manufacturing and scale-up was developed. We describe here a large-scale (50-liter) vector production process capable of achieving crude titers on the order of 10(9) plaque-forming units (PFU)/ml under cGMP. This process was used to generate a master virus seed stock and a clinical lot of the clinical trial agent under cGMP with an infectious viral titer of approximately 2 × 10(10) PFU/ml (total yield, 1 × 10(13) PFU). The lot has passed all U.S. Food and Drug Administration-mandated release testing and will be used in a phase 1 clinical translational trial in patients with advanced HCC.

  17. Reovirus FAST Protein Enhances Vesicular Stomatitis Virus Oncolytic Virotherapy in Primary and Metastatic Tumor Models

    Directory of Open Access Journals (Sweden)

    Fabrice Le Boeuf

    2017-09-01

    Full Text Available The reovirus fusion-associated small transmembrane (FAST proteins are the smallest known viral fusogens (∼100–150 amino acids and efficiently induce cell-cell fusion and syncytium formation in multiple cell types. Syncytium formation enhances cell-cell virus transmission and may also induce immunogenic cell death, a form of apoptosis that stimulates immune recognition of tumor cells. These properties suggest that FAST proteins might serve to enhance oncolytic virotherapy. The oncolytic activity of recombinant VSVΔM51 (an interferon-sensitive vesicular stomatitis virus [VSV] mutant encoding the p14 FAST protein (VSV-p14 was compared with a similar construct encoding GFP (VSV-GFP in cell culture and syngeneic BALB/c tumor models. Compared with VSV-GFP, VSV-p14 exhibited increased oncolytic activity against MCF-7 and 4T1 breast cancer spheroids in culture and reduced primary 4T1 breast tumor growth in vivo. VSV-p14 prolonged survival in both primary and metastatic 4T1 breast cancer models, and in a CT26 metastatic colon cancer model. As with VSV-GFP, VSV-p14 preferentially replicated in vivo in tumors and was cleared rapidly from other sites. Furthermore, VSV-p14 increased the numbers of activated splenic CD4, CD8, natural killer (NK, and natural killer T (NKT cells, and increased the number of activated CD4 and CD8 cells in tumors. FAST proteins may therefore provide a multi-pronged approach to improving oncolytic virotherapy via syncytium formation and enhanced immune stimulation.

  18. Vesicular stomatitis virus-based vaccines protect nonhuman primates against Bundibugyo ebolavirus.

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    Chad E Mire

    Full Text Available Ebola virus (EBOV causes severe and often fatal hemorrhagic fever in humans and nonhuman primates (NHPs. Currently, there are no licensed vaccines or therapeutics for human use. Recombinant vesicular stomatitis virus (rVSV-based vaccine vectors, which encode an EBOV glycoprotein in place of the VSV glycoprotein, have shown 100% efficacy against homologous Sudan ebolavirus (SEBOV or Zaire ebolavirus (ZEBOV challenge in NHPs. In addition, a single injection of a blend of three rVSV vectors completely protected NHPs against challenge with SEBOV, ZEBOV, the former Côte d'Ivoire ebolavirus, and Marburg virus. However, recent studies suggest that complete protection against the newly discovered Bundibugyo ebolavirus (BEBOV using several different heterologous filovirus vaccines is more difficult and presents a new challenge. As BEBOV caused nearly 50% mortality in a recent outbreak any filovirus vaccine advanced for human use must be able to protect against this new species. Here, we evaluated several different strategies against BEBOV using rVSV-based vaccines. Groups of cynomolgus macaques were vaccinated with a single injection of a homologous BEBOV vaccine, a single injection of a blended heterologous vaccine (SEBOV/ZEBOV, or a prime-boost using heterologous SEBOV and ZEBOV vectors. Animals were challenged with BEBOV 29-36 days after initial vaccination. Macaques vaccinated with the homologous BEBOV vaccine or the prime-boost showed no overt signs of illness and survived challenge. In contrast, animals vaccinated with the heterologous blended vaccine and unvaccinated control animals developed severe clinical symptoms consistent with BEBOV infection with 2 of 3 animals in each group succumbing. These data show that complete protection against BEBOV will likely require incorporation of BEBOV glycoprotein into the vaccine or employment of a prime-boost regimen. Fortunately, our results demonstrate that heterologous rVSV-based filovirus vaccine

  19. Vesicular-arbuscular mycorrhiza response to crossed carbon and phosphorus resource gradients

    Energy Technology Data Exchange (ETDEWEB)

    Whitbeck, J.L. (Pennyslvania State Univ., University Park, PA (United States))

    1994-06-01

    Employing the annual herb Hemizonia luzulaefolia, native to nutrient limited grassland ecosystem in California, and a community of indigenous vesicular-arbuscular mycorrhizal (VAM) fungi, this study examined mycorrhizal response to interacting plant- and fungus-acquired resources. Plant carbon supply was manipulated through atmospheric carbon dioxide (CO[sub 2]) concentration, and substrate phosphorus (P) supply was varied in the nutrient solution. H. luzulaefolia responded strongly to VAM association, showing increased root and shoot biomass, greater leaf area, higher shoot P content and lower specific root length relative to non-mycorrhizal plants. Elevated (700 ppm) CO[sub 2] plants had lower mass, lower root:shoot ratios and slightly greater specific root length than ambient pCO[sub 2]-grown plants. VAM colonization of roots was stimulated by elevated CO[sub 2] early in the experiment. Low P plants showed greater leaf mass per area and lower shoot P concentration than plus-P plants. P effects on measures of VAM changed over time. While ambient pCO[sub 2]-grown plants responsed to added P with increased biomass, plants grown at elevated CO[sub 2] showed equivalent or lower biomass in plus-P treatments than in those with no added P. At the same time, ambient pCO[sub 2]-grown plants developed greater VAM colonization of roots in low P treatments, while at 700 ppm CO[sub 2]. VAM colonization was higher in plus-P treatments. It appears that atmospheric pCO[sub 2] affects the patterns of belowground allocation in H. luzulaefolia: ambient pCO[sub 2] plants direct carbon resources to VAM when P is low and to roots when P is available, while elevated CO[sub 2] plants maintain VAM colonization regardless of P environment and allocate to roots when P is low.

  20. Dromedary milk exosomes as mammary transcriptome nano-vehicle: Their isolation, vesicular and phospholipidomic characterizatio

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    Aya M. Yassin

    2016-09-01

    Full Text Available Exosomes are extracellular nanovesicles that play a role in cellular trafficking and communication. Camel milk exosomes might carry the potential of recovery of several illnesses that coins the dromedary milk. This study shows for the first time their isolation and fine characterization. The differential ultracentrifugation was used for their isolation. Their recovery from dromedary milk during different lactation periods was evaluated. The vesicular characterization and stability testing of the recovered exosome were examined by transmission electron microscopy (TEM. The proteome footprinting was resolved by gel electrophoresis prior to their specific protein biomarker analysis. The immunoblotting of their specific protein biomarker TSG101 unexpectedly revealed a truncated 35 KDa protein specific for dromedary milk exosome rather than the previously reported 43 KDa mammalian one. The reversed-phase HPLC screening of their phospholipid makeup was compared with that of cattle milk exosomes at different lactation periods. Since dromedary milk exosomes reflect their mammary transcriptome outcome, further assessment of their content of αs1casein, αs2casein β-casein κ-casein mRNAs parallel with a constitutive glyceraldehyde dehydrogenase (GAPD gene was performed using real-time PCR. The TEM scanning indicated that dromedary milk exosomes are freeze-stress unstable homogeneous with average size of 30 nm. There was no significant difference in expression level of different casein genes in mid lactation period in dromedary milk exosomes over late lactation period. The phospholipidomic survey proved that phosphatidylcholine is the major candidate of the examined phospholipids in dromedary milk exosomes. The obtained data give novel interpretation about the content of camel milk exosomes with possible insight for use as potentially-safe nano carrier.

  1. Vesicular Trafficking Systems Impact TORC1-Controlled Transcriptional Programs in Saccharomyces cerevisiae

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    Joanne M. Kingsbury

    2016-03-01

    Full Text Available The Target of Rapamycin Complex I (TORC1 orchestrates global reprogramming of transcriptional programs in response to myriad environmental conditions, yet, despite the commonality of the TORC1 complex components, different TORC1-inhibitory conditions do not elicit a uniform transcriptional response. In Saccharomyces cerevisiae, TORC1 regulates the expression of nitrogen catabolite repressed (NCR genes by controlling the nuclear translocation of the NCR transactivator Gln3. Moreover, Golgi-to-endosome trafficking was shown to be required for nuclear translocation of Gln3 upon a shift from rich medium to the poor nitrogen source proline, but not upon rapamycin treatment. Here, we employed microarray profiling to survey the full impact of the vesicular trafficking system on yeast TORC1-orchestrated transcriptional programs. In addition to the NCR genes, we found that ribosomal protein, ribosome biogenesis, phosphate-responsive, and sulfur-containing amino acid metabolism genes are perturbed by disruption of Golgi-to-endosome trafficking following a nutritional shift from rich to poor nitrogen source medium, but not upon rapamycin treatment. Similar to Gln3, defects in Golgi-to-endosome trafficking significantly delayed cytoplasmic–nuclear translocation of Sfp1, but did not detectably affect the cytoplasmic–nuclear or nuclear–cytoplasmic translocation of Met4, which are the transactivators of these genes. Thus, Golgi-to-endosome trafficking defects perturb TORC1 transcriptional programs via multiple mechanisms. Our findings further delineate the downstream transcriptional responses of TORC1 inhibition by rapamycin compared with a nitrogen quality downshift. Given the conservation of both TORC1 and endomembrane networks throughout eukaryotes, our findings may also have implications for TORC1-mediated responses to nutritional cues in mammals and other eukaryotes.

  2. Vesicular Trafficking Systems Impact TORC1-Controlled Transcriptional Programs in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kingsbury, Joanne M; Cardenas, Maria E

    2016-01-06

    The Target of Rapamycin Complex I (TORC1) orchestrates global reprogramming of transcriptional programs in response to myriad environmental conditions, yet, despite the commonality of the TORC1 complex components, different TORC1-inhibitory conditions do not elicit a uniform transcriptional response. In Saccharomyces cerevisiae, TORC1 regulates the expression of nitrogen catabolite repressed (NCR) genes by controlling the nuclear translocation of the NCR transactivator Gln3. Moreover, Golgi-to-endosome trafficking was shown to be required for nuclear translocation of Gln3 upon a shift from rich medium to the poor nitrogen source proline, but not upon rapamycin treatment. Here, we employed microarray profiling to survey the full impact of the vesicular trafficking system on yeast TORC1-orchestrated transcriptional programs. In addition to the NCR genes, we found that ribosomal protein, ribosome biogenesis, phosphate-responsive, and sulfur-containing amino acid metabolism genes are perturbed by disruption of Golgi-to-endosome trafficking following a nutritional shift from rich to poor nitrogen source medium, but not upon rapamycin treatment. Similar to Gln3, defects in Golgi-to-endosome trafficking significantly delayed cytoplasmic-nuclear translocation of Sfp1, but did not detectably affect the cytoplasmic-nuclear or nuclear-cytoplasmic translocation of Met4, which are the transactivators of these genes. Thus, Golgi-to-endosome trafficking defects perturb TORC1 transcriptional programs via multiple mechanisms. Our findings further delineate the downstream transcriptional responses of TORC1 inhibition by rapamycin compared with a nitrogen quality downshift. Given the conservation of both TORC1 and endomembrane networks throughout eukaryotes, our findings may also have implications for TORC1-mediated responses to nutritional cues in mammals and other eukaryotes. Copyright © 2016 Kingsbury and Cardenas.

  3. Oncolytic efficacy of recombinant vesicular stomatitis virus and myxoma virus in experimental models of rhabdoid tumors.

    Science.gov (United States)

    Wu, Yushui; Lun, Xueqing; Zhou, Hongyuan; Wang, Limei; Sun, Beichen; Bell, John C; Barrett, John W; McFadden, Grant; Biegel, Jaclyn A; Senger, Donna L; Forsyth, Peter A

    2008-02-15

    Rhabdoid tumors are highly aggressive pediatric tumors that are usually refractory to available treatments. The purpose of this study was to evaluate the therapeutic potential of two oncolytic viruses, myxoma virus (MV) and an attenuated vesicular stomatitis virus (VSV(DeltaM51)), in experimental models of human rhabdoid tumor. Four human rhabdoid tumor cell lines were cultured in vitro and treated with live or inactivated control virus. Cytopathic effect, viral gene expression, infectious viral titers, and cell viability were examined at various time points after infection. To study viral oncolysis in vivo, human rhabdoid tumor cells were implanted s.c. in the hind flank or intracranially in CD-1 nude mice and treated with intratumoral (i.t.) or i.v. injections of live or UV-inactivated virus. Viral distribution and effects on tumor size and survival were assessed. All rhabdoid tumor cell lines tested in vitro were susceptible to productive lethal infections by MV and VSV(DeltaM51). I.t. injection of live MV or VSV(DeltaM51) dramatically reduced the size of s.c. rhabdoid tumor xenografts compared with control animals. I.v. administration of VSV(DeltaM51) or i.t. injection of MV prolonged the median survival of mice with brain xenografts compared with controls (VSV(DeltaM51): 25 days versus 21 days, log-rank test, P = 0.0036; MV: median survival not reached versus 21 days, log-rank test, P = 0.0007). Most of the MV-treated animals (4 of 6; 66.7%) were alive and apparently "cured" when the experiment was arbitrarily ended (>180 days). These results suggest that VSV(DeltaM51) and MV could be novel effective therapies against human rhabdoid tumor.

  4. [Serological examinations for swine vesicular disease (SVD) in a closed pig breeding herd using ELISA].

    Science.gov (United States)

    Pannwitz, Gunter; Haas, Bernd; Hoffmann, Bernd; Fischer, Sebastian

    2009-01-01

    In a closed pig establishment housing about 18,000 pigs, 2895 gilts were tested pre-export for SVD (swine vesicular disease) antibodies using Ceditest/PrioCHECK SVDV-AB ELISA. 130 gilts (4.5%) tested positive. In addition, 561 animals of this farm were sampled per random for SVD serology. One in 241 weaners (0.4%), eight in 150 gilts (5.3%) and 18 in 170 (10.6%) pregnant sows tested ELISA SVD-antibody positive. Of the ELISA positive samples, 23 tested positive in VNT (virus neutralization test). Of these, 20 VNT-positive animals were re-sampled two weeks later and re-tested via ELISA and VNT in different laboratories, displaying falling titres with one to two animals remaining VNT-positive. Epidemiological investigations and clinical examinations on site did not yield any evidence for SVD. 745 faecal samples taken from individual pigs and collected from pens tested negative in SVDV-RNA-PCR. 40 of these samples tested negative in virus isolation on cell culture. Pathological examinations on fallen pigs did not reveal any evidence for SVD either. After comparing our ELISA results with data recorded in the ELISA validation by Chenard et al. (1998), we propose that the published test performance is perhaps not currently applicable for the commercial test. Provided that SVD-antibody negative pigs were tested, a specificity of 99.6% in weaners, 95.5% in gilts and 89.4% in pregnant sows would appear to be more appropriate for the Ceditest/PrioCHECK SVDV-AB ELISA. Details are provided for all examined pigs regarding husbandry, breed, age, weeks pregnant and previous vaccinations. The results of other serological tests on the same sera are given. Possible clusterings of false-positive SVD-ELISA results are discussed.

  5. Salidroside protects cortical neurons against glutamate-induced cytotoxicity by inhibiting autophagy.

    Science.gov (United States)

    Yin, Wei-Yong; Ye, Qiang; Huang, Huan-Jie; Xia, Nian-Ge; Chen, Yan-Yan; Zhang, Yi; Qu, Qiu-Min

    2016-08-01

    Recent evidence suggests that glutamate-induced cytotoxicity contributes to autophagic neuron death and is partially mediated by increased oxidative stress. Salidroside has been demonstrated to have neuroprotective effects in glutamate-induced neuronal damage. The precise mechanism of its regulatory role in neuronal autophagy is, however, poorly understood. This study aimed to probe the effects and mechanisms of salidroside in glutamate-induced autophagy activation in cultured rat cortical neurons. Cell viability assay, Western blotting, coimmunoprecipitation, and small interfering RNA were performed to analyze autophagy activities during glutamate-evoked oxidative injury. We found that salidroside protected neonatal neurons from glutamate-induced apoptotic cell death. Salidroside significantly attenuated the LC3-II/LC3-I ratio and expression of Beclin-1, but increased (SQSTM1)/p62 expression under glutamate exposure. Pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, decreased LC3-II/LC3-I ratio, attenuated glutamate-induced cell injury, and mimicked some of the protective effects of salidroside against glutamate-induced cell injury. Molecular analysis demonstrated that salidroside inhibited cortical neuron autophagy in response to glutamate exposure through p53 signaling by increasing the accumulation of cytoplasmic p53. Salidroside inhibited the glutamate-induced dissociation of the Bcl-2-Beclin-1 complex with minor affects on the PI3K/Akt/mTOR signaling pathways. These data demonstrate that the inhibition of autophagy could be responsible for the neuroprotective effects of salidroside on glutamate-induced neuronal injury.

  6. GDH-Dependent Glutamate Oxidation in the Brain Dictates Peripheral Energy Substrate Distribution

    DEFF Research Database (Denmark)

    Karaca, Melis; Frigerio, Francesca; Migrenne, Stephanie

    2015-01-01

    Glucose, the main energy substrate used in the CNS, is continuously supplied by the periphery. Glutamate, the major excitatory neurotransmitter, is foreseen as a complementary energy contributor in the brain. In particular, astrocytes actively take up glutamate and may use it through oxidative...... glutamate dehydrogenase (GDH) activity. Here, we investigated the significance of glutamate as energy substrate for the brain. Upon glutamate exposure, astrocytes generated ATP in a GDH-dependent way. The observed lack of glutamate oxidation in brain-specific GDH null CnsGlud1(-/-) mice resulted....... Our data reveal the importance of glutamate as necessary energy substrate for the brain and the role of central GDH in the regulation of whole-body energy homeostasis....

  7. Glutamic acid and its derivatives: candidates for rational design of anticancer drugs.

    Science.gov (United States)

    Ali, Imran; Wani, Waseem A; Haque, Ashanul; Saleem, Kishwar

    2013-05-01

    Throughout the history of human civilizations, cancer has been a major health problem. Its treatment has been interesting but challenging to scientists. Glutamic acid and its derivative glutamine are known to play interesting roles in cancer genesis, hence, it was realized that structurally variant glutamic acid derivatives may be designed and developed and, might be having antagonistic effects on cancer. The present article describes the state-of-art of glutamic acid and its derivatives as anticancer agents. Attempts have been made to explore the effectivity of drug-delivery systems based on glutamic acid for the delivery of anticancer drugs. Moreover, efforts have also been made to discuss the mechanism of action of glutamic acid derivatives as anticancer agents, clinical applications of glutamic acid derivatives, as well as recent developments and future perspectives of glutamic acid drug development have also been discussed.

  8. Strains of Lentinula edodes suppress growth of phytopathogenic fungi and inhibit Alagoas serotype of vesicular stomatitis virus Linhagens de Lentinula edodes inibem fungos fitopatogênicos e o vírus da estomatite vesicular, sorotipo Alagoas

    Directory of Open Access Journals (Sweden)

    Selma H. Sasaki

    2001-03-01

    Full Text Available Four Lentinula edodes strains (Le10, 46, K2, Assai were assessed for their antagonistic effect on four filamentous fungus species of agricultural importance (Helminthosporium euphorbiae, Helminthosporium sp, Fusarium solani and Phomopsis sojae and on Alagoas serotype of Vesicular Stomatitis Virus (VSA. The L. edodes strains studied had variable effects on the filamentous fungi and on VSA. The K2 and Le10 strains were antagonistic on the fungi assessed and the 46 and K2 strains were efficient on the Vesicular Stomatitis Virus. The results widened the list of beneficial effects of L. edodes on the control and prevention of animal pathogenic virus and filamentous fungi.Quatro linhagens de Lentinula edodes (Le10, 46, K2, ASSAI foram avaliadas quanto ao seu efeito inibitório sobre quatro espécies de fungos filamentosos de importância agrícola (Helminthosporium euphorbiae, Helminthosporium sp., Fusarium solani, Phomopsis sojae e sobre o sorotipo Alagoas vírus da estomatite vesicular (VSA. Foi observado que as linhagens de L. edodes estudadas apresentaram variabilidade quanto ao seu efeito, tanto sobre os fungos filamentosos quanto sobre o vírus VSA. As linhagens K2 e Le10 apresentaram-se antagônicas sobre os fungos e as linhagens 46 e K2 foram eficientes na inibição do vírus VSA. Os resultados obtidos permitem ampliar a lista de efeitos benéficos de algumas linhagens de L. edodes no controle e prevenção de vírus patogênicos animais e de fungos filamentosos.

  9. Genes involved in Drosophila glutamate receptor expression and localization

    Directory of Open Access Journals (Sweden)

    Featherstone David E

    2005-06-01

    Full Text Available Abstract Background A clear picture of the mechanisms controlling glutamate receptor expression, localization, and stability remains elusive, possibly due to an incomplete understanding of the proteins involved. We screened transposon mutants generated by the ongoing Drosophila Gene Disruption Project in an effort to identify the different types of genes required for glutamate receptor cluster development. Results To enrich for non-silent insertions with severe disruptions in glutamate receptor clustering, we identified and focused on homozygous lethal mutants in a collection of 2185 BG and KG transposon mutants generated by the BDGP Gene Disruption Project. 202 lethal mutant lines were individually dissected to expose glutamatergic neuromuscular junctions, stained using antibodies that recognize neuronal membrane and the glutamate receptor subunit GluRIIA, and viewed using laser-scanning confocal microscopy. We identified 57 mutants with qualitative differences in GluRIIA expression and/or localization. 84% of mutants showed loss of receptors and/or clusters; 16% of mutants showed an increase in receptors. Insertion loci encode a variety of protein types, including cytoskeleton proteins and regulators, kinases, phosphatases, ubiquitin ligases, mucins, cell adhesion proteins, transporters, proteins controlling gene expression and protein translation, and proteins of unknown/novel function. Expression pattern analyses and complementation tests, however, suggest that any single mutant – even if a mutant gene is uniquely tagged – must be interpreted with caution until the mutation is validated genetically and phenotypically. Conclusion Our study identified 57 transposon mutants with qualitative differences in glutamate receptor expression and localization. Despite transposon tagging of every insertion locus, extensive validation is needed before one can have confidence in the role of any individual gene. Alternatively, one can focus on the

  10. Glutamate Metabolism in Brain Structures in Experimental Hemorrhagic Shock

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    V. N. Jakovlev

    2017-01-01

    Full Text Available Purpose. To study glutamate metabolism characteristics in phylogenetically different parts of the mammalian brain in experimentally induced hemorrhagic shock (HS in cats.Material and methods. Experiments were performed on 76 cats. HS was induced by intermittent bloodletting from femoral artery at a rate of 10ml/kg•10 minutes, with the average volume of 24±0.8 ml/kg. The bloodletting was discontinued after arterial pressure (BP drop to 60.0±1.5 mmHg. We studied ammonia, glutamate (Gt, and α-ketoglutarate (α-KG levels and glutaminase (GS and glutamate dehydrogenase (GDG activity in specimens harvested from phylogenetically different parts of the brain (cortex, limbic system, diencephalon, and medulla oblongata.Results. In intact animals, the peak GDG activity was found in the medulla oblongata (phylogenetically the oldest part of the brain and the peak GS activity was registered in the sensorimotor cortex (phylogenetically the youngest part of the brain; the glutaminase activity did not depend on the phylogenetic age of brain structures.In the case of HS, Gt metabolism changes began in the sensorimotor cortex manifested by decreased GS activity, which progresses by the 70th minute of the post%hemorrhagic period (PHP accompanied by delayed increase in the GDG and glutaminase activity, as well as Gt accumulation. In the limbic system and diencephalon the Gt metabolism was changing (impaired glutamine synthesis, stimuled Gt synthesis with glutamine desamidization and α%KG amination when developed by the 70th minute of the PHP. Similarly to sensorimotor cortex, changes were associated with Gt accumulation. During the agony, α%KG deficiency developed in all parts of the brain as a result of its increased contribution to Gt synthesis. At the same period of time, in the sensorimotor cortex, limbic system and diencephalon the Gt synthesis from glutamine was stimulated, however, the Gt contribution tothe formation of glutamine was decreased. The

  11. High-Throughput Assay Development for Cystine-Glutamate Antiporter (xc- Highlights Faster Cystine Uptake than Glutamate Release in Glioma Cells.

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    Ajit G Thomas

    Full Text Available The cystine-glutamate antiporter (system xc- is a Na+-independent amino acid transporter that exchanges extracellular cystine for intracellular glutamate. It is thought to play a critical role in cellular redox processes through regulation of intracellular glutathione synthesis via cystine uptake. In gliomas, system xc- expression is universally up-regulated while that of glutamate transporters down-regulated, leading to a progressive accumulation of extracellular glutamate and excitotoxic cell death of the surrounding non-tumorous tissue. Additionally, up-regulation of system xc- in activated microglia has been implicated in the pathogenesis of several neurodegenerative disorders mediated by excess glutamate. Consequently, system xc- is a new drug target for brain cancer and neuroinflammatory diseases associated with excess extracellular glutamate. Unfortunately no potent and selective small molecule system xc- inhibitors exist and to our knowledge, no high throughput screening (HTS assay has been developed to identify new scaffolds for inhibitor design. To develop such an assay, various neuronal and non-neuronal human cells were evaluated as sources of system xc-. Human glioma cells were chosen based on their high system xc- activity. Using these cells, [14C]-cystine uptake and cystine-induced glutamate release assays were characterized and optimized with respect to cystine and protein concentrations and time of incubation. A pilot screen of the LOPAC/NINDS libraries using glutamate release demonstrated that the logistics of the assay were in place but unfortunately, did not yield meaningful pharmacophores. A larger, HTS campaign using the 384-well cystine-induced glutamate release as primary assay and the 96-well 14C-cystine uptake as confirmatory assay is currently underway. Unexpectedly, we observed that the rate of cystine uptake was significantly faster than the rate of glutamate release in human glioma cells. This was in contrast to the

  12. The Leishmania donovani lipophosphoglycan excludes the vesicular proton-ATPase from phagosomes by impairing the recruitment of synaptotagmin V.

    Directory of Open Access Journals (Sweden)

    Adrien F Vinet

    2009-10-01

    Full Text Available We recently showed that the exocytosis regulator Synaptotagmin (Syt V is recruited to the nascent phagosome and remains associated throughout the maturation process. In this study, we investigated the possibility that Syt V plays a role in regulating interactions between the phagosome and the endocytic organelles. Silencing of Syt V by RNA interference revealed that Syt V contributes to phagolysosome biogenesis by regulating the acquisition of cathepsin D and the vesicular proton-ATPase. In contrast, recruitment of cathepsin B, the early endosomal marker EEA1 and the lysosomal marker LAMP1 to phagosomes was normal in the absence of Syt V. As Leishmania donovani promastigotes inhibit phagosome maturation, we investigated their potential impact on the phagosomal association of Syt V. This inhibition of phagolysosome biogenesis is mediated by the virulence glycolipid lipophosphoglycan, a polymer of the repeating Galbeta1,4Manalpha1-PO(4 units attached to the promastigote surface via an unusual glycosylphosphatidylinositol anchor. Our results showed that insertion of lipophosphoglycan into ganglioside GM1-containing microdomains excluded or caused dissociation of Syt V from phagosome membranes. As a consequence, L. donovani promatigotes established infection in a phagosome from which the vesicular proton-ATPase was excluded and which failed to acidify. Collectively, these results reveal a novel function for Syt V in phagolysosome biogenesis and provide novel insight into the mechanism of vesicular proton-ATPase recruitment to maturing phagosomes. We also provide novel findings into the mechanism of Leishmania pathogenesis, whereby targeting of Syt V is part of the strategy used by L. donovani promastigotes to prevent phagosome acidification.

  13. Effect of the mineralogical composition on the petrophysical behavior of the amygdaloidal and vesicular basalt of Wadi Wizr, Eastern Desert, Egypt

    Science.gov (United States)

    Nabawy, Bassem S.; Wassif, Nadia A.

    2017-10-01

    This paper gives an account of the petrophysical characteristics and the petrographical descriptions of Tertiary vesicular and amygdaloidal olivine basalt flows from Wadi Wizr in the central Eastern Desert of Egypt. The petrographical studies indicated that the studied vesicular basalts are rich in calcic-plagioclase, augite and olivine in addition to numerous amounts of fine opaque minerals and vesicles filled with carbonate and quartz amygdales. The degree of oxidation and alteration of magnetite and ilmenite are discussed in detail. Petrophysically, the studied samples can be grouped into two main groups; the first group includes amygdaloidal basalts and the second group consists of vesicular basalts. The vesicular group (the permeable one) is characterized by fair to very good porosity (∅), good permeability (k), very low true formation resistivity factor (F) and contain micro to ultra micropores. On the other hand, the amygdaloidal basalt group (impermeable group) is characterized by very low storage capacity properties, fair porosity, negligible permeability, medium to high true formation resistivity factor and ultra micropores. The mercury injection capillary pressure technique (MICP) indicates that the pore throats of the studied vesicular samples have a binomial distribution (rank IV), while that of the amygdaloidal samples have a trinomial distribution (rank V). It has been found in this study that the petrophysical behavior of basalts is dependent on the degree of oxidation and alteration; and in particular on the rate of cooling and oxidation of the opaque minerals which caused filling in the primarily produced vesicles by low temperature secondary minerals.

  14. Antibodies to a recombinant glutamate-rich Plasmodium falciparum protein

    DEFF Research Database (Denmark)

    Hogh, B; Petersen, E; Dziegiel, M

    1992-01-01

    A Plasmodium falciparum antigen gene coding for a 220-kD glutamate-rich protein (GLURP) has been cloned, and the 783 C-terminal amino acids of this protein (GLURP489-1271) have been expressed as a beta-galactosidase fusion protein in Escherichia coli. The encoded 783 amino acid residues contain two...... areas of repeated amino acid sequences. Antibodies against recombinant GLURP489-1271, as well as against a synthetic peptide corresponding to GLURP899-916, and against a synthetic peptide representing the major glutamate rich repeat sequence from the P. falciparum ring erythrocyte surface antigen (Pf155...... between the anti-GLURP489-1271 and anti-(EENV)6 antibody responses. The data provide indirect evidence for a protective role of antibodies reacting with recombinant GLURP489-1271 as well as with the synthetic peptide (EENV)6 from the Pf155/RESA....

  15. Sexual attraction enhances glutamate transmission in mammalian anterior cingulate cortex

    Directory of Open Access Journals (Sweden)

    Wu Long-Jun

    2009-05-01

    Full Text Available Abstract Functional human brain imaging studies have indicated the essential role of cortical regions, such as the anterior cingulate cortex (ACC, in romantic love and sex. However, the neurobiological basis of how the ACC neurons are activated and engaged in sexual attraction remains unknown. Using transgenic mice in which the expression of green fluorescent protein (GFP is controlled by the promoter of the activity-dependent gene c-fos, we found that ACC pyramidal neurons are activated by sexual attraction. The presynaptic glutamate release to the activated neurons is increased and pharmacological inhibition of neuronal activities in the ACC reduced the interest of male mice to female mice. Our results present direct evidence of the critical role of the ACC in sexual attraction, and long-term increases in glutamate mediated excitatory transmission may contribute to sexual attraction between male and female mice.

  16. Glutamate metabolism in the brain focusing on astrocytes

    DEFF Research Database (Denmark)

    Schousboe, Arne; Scafidi, Susanna; Bak, Lasse Kristoffer

    2014-01-01

    Metabolism of glutamate, the main excitatory neurotransmitter and precursor of GABA, is exceedingly complex and highly compartmentalized in brain. Maintenance of these neurotransmitter pools is strictly dependent on the de novo synthesis of glutamine in astrocytes which requires both the anaplero......Metabolism of glutamate, the main excitatory neurotransmitter and precursor of GABA, is exceedingly complex and highly compartmentalized in brain. Maintenance of these neurotransmitter pools is strictly dependent on the de novo synthesis of glutamine in astrocytes which requires both......, as well as in nitrogen trafficking and ammonia homeostasis in brain. The anatomical specialization of astrocytic endfeet enables these cells to rapidly and efficiently remove neurotransmitters from the synaptic cleft to maintain homeostasis, and to provide glutamine to replenish neurotransmitter pools...... summarizes the evidence that astrocytes are essential and dynamic partners in both glutamatergic and GABAergic neurotransmission in brain....

  17. Leptin regulates glutamate and glucose transporters in hypothalamic astrocytes

    Science.gov (United States)

    Fuente-Martín, Esther; García-Cáceres, Cristina; Granado, Miriam; de Ceballos, María L.; Sánchez-Garrido, Miguel Ángel; Sarman, Beatrix; Liu, Zhong-Wu; Dietrich, Marcelo O.; Tena-Sempere, Manuel; Argente-Arizón, Pilar; Díaz, Francisca; Argente, Jesús; Horvath, Tamas L.; Chowen, Julie A.

    2012-01-01

    Glial cells perform critical functions that alter the metabolism and activity of neurons, and there is increasing interest in their role in appetite and energy balance. Leptin, a key regulator of appetite and metabolism, has previously been reported to influence glial structural proteins and morphology. Here, we demonstrate that metabolic status and leptin also modify astrocyte-specific glutamate and glucose transporters, indicating that metabolic signals influence synaptic efficacy and glucose uptake and, ultimately, neuronal function. We found that basal and glucose-stimulated electrical activity of hypothalamic proopiomelanocortin (POMC) neurons in mice were altered in the offspring of mothers fed a high-fat diet. In adulthood, increased body weight and fasting also altered the expression of glucose and glutamate transporters. These results demonstrate that whole-organism metabolism alters hypothalamic glial cell activity and suggest that these cells play an important role in the pathology of obesity. PMID:23064363

  18. Conformation of poly(γ-glutamic acid) in aqueous solution.

    Science.gov (United States)

    Muroga, Yoshio; Nakaya, Asami; Inoue, Atsuki; Itoh, Daiki; Abiru, Masaya; Wada, Kaori; Takada, Masako; Ikake, Hiroki; Shimizu, Shigeru

    2016-04-01

    Local conformation and overall conformation of poly(γ-DL-glutamic acid) (PγDLGA) and poly(γ-L-glutamic acid) (PγLGA) in aqueous solution was studied as a function of degree of ionization ε by (1) H-NMR, circular dichroism, and potentiometric titration. It was clarified that their local conformation is represented by random coil over an entire ε range and their overall conformation is represented by expanded random-coil in a range of ε > ε(*) , where ε(*) is about 0.3, 0.35, 0.45, and 0.5 for added-salt concentration of 0.02M, 0.05M, 0.1M, and 0.2M, respectively. In a range of ε acidic media. © 2015 Wiley Periodicals, Inc.

  19. Fístula colecistoduodenal, complicación infrecuente de litiasis vesicular: nuestra experiencia en su manejo quirúrgico

    Directory of Open Access Journals (Sweden)

    F. Aguilar-Espinosa

    2017-10-01

    Conclusiones: La incidencia de fístula colecistoduodenal fue similar a la reportada en la literatura médica: es una complicación poco común de litiasis vesicular y su diagnóstico es difícil por la sintomatología poco específica. Se debe tener en cuenta en pacientes adultos mayores, en los que se encuentra vesícula biliar escleroatrófica y múltiples adherencias.

  20. Cooperation of B cells and T cells is required for survival of mice infected with vesicular stomatitis virus

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Nansen, A; Andersen, C

    1997-01-01

    To define the role of T cells and B cells in resistance to vesicular stomatitis virus (VSV) infection, knockout mice with different specific immune defects on an identical background were infected i.v. and the outcome of infection was compared; in this way a more complete picture of the relative...... antibodies are pivotal for survival in the early phase of VSV infection, T cells are required for long-term survival, with CD4+ T cells being more effective in controlling this infection than CD8+ T cells....

  1. Quantitative multiplex assay for simultaneous detection and identification of Indiana and New Jersey serotypes of vesicular stomatitis virus

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Uttenthal, Åse; Fernandez, Jovita

    2005-01-01

    In order to establish a rapid and reliable system for the detection of vesicular stomatitis virus (VSV), we developed a quantitative reverse transcription-PCR assay for the detection, quantification, and differentiation of the major serotypes, VSV Indiana and VSV New Jersey, using a closed......-tube multiplex format. The detection system is based on the recently invented primer-probe energy transfer (PriProET) system. A region of the gene encoding the RNA-dependent RNA polymerase was amplified by using VSV-specific primers in the presence of two serotype-specific fluorescent probes. By incorporating...... identification of VSV....

  2. Large-population passages of vesicular stomatitis virus in interferon-treated cells select variants of only limited resistance.

    OpenAIRE

    Novella, I S; Cilnis, M; Elena, S F; Kohn, J.; Moya, A; Domingo, E; Holland, J J

    1996-01-01

    Vesicular stomatitis virus (VSV) populations were repeatedly passaged in L-929 cells treated with alpha interferon (IFN-alpha) at levels of 25 U/ml. This IFN-alpha concentration induced a 99.9% inhibition of viral yield in standard infections. Analysis of viral fitness (overall replicative ability measured in direct competition with a reference wild-type VSV) after 21 passages in IFN-treated cells showed only a limited increase or no increase in fitness, compared with the greater increase upo...

  3. The lipidomes of vesicular stomatitis virus, semliki forest virus, and the host plasma membrane analyzed by quantitative shotgun mass spectrometry

    DEFF Research Database (Denmark)

    Kalvodova, Lucie; Sampaio, Julio L; Cordo, Sandra

    2009-01-01

    Although enveloped virus assembly in the host cell is a crucial step in the virus life cycle, it remains poorly understood. One issue is how viruses include lipids in their membranes during budding from infected host cells. To analyze this issue, we took advantage of the fact that baby hamster...... kidney cells can be infected by two different viruses, namely, vesicular stomatitis virus and Semliki Forest virus, from the Rhabdoviridae and Togaviridae families, respectively. We purified the host plasma membrane and the two different viruses after exit from the host cells and analyzed the lipid...

  4. Trojan horse lymphocytes: a vesicular stomatitis virus-specific T-cell clone lyses target cells by carrying virus.

    OpenAIRE

    Hom, R C; Soman, G; Finberg, R

    1989-01-01

    We have isolated a vesicular stomatitis virus (VSV)-specific CD4+ CD8- murine T-cell clone. This clone proliferates only in response to VSV and lyses infected tumor cells bearing class II major histocompatibility antigens in short-term chromium release assays. In addition, the cell has VSV antigens on its surface and is capable of killing uninfected tumor cells without major histocompatibility antigen restriction in a 2-day assay. This latter cytolytic activity is eliminated by anti-VSV antib...

  5. Faster flux of neurotransmitter glutamate during seizure - Evidence from 13C-enrichment of extracellular glutamate in kainate rat model.

    Directory of Open Access Journals (Sweden)

    Keiko Kanamori

    Full Text Available The objective is to examine how the flux of neurotransmitter glutamate from neurons to the extracellular fluid, as measured by the rate of 13C enrichment of extracellular glutamate (GLUECF, changes in response to seizures in the kainate-induced rat model of temporal-lobe epilepsy. Following unilateral intrahippocampal injection of kainate, GLUECF was collected by microdialysis from the CA1/CA3 region of awake rats, in combination with EEG recording of chronic-phase recurrent seizures and intravenous infusion of [2,5-13C]glucose. The 13C enrichment of GLUECF C5 at ~ 10 picomol level was measured by gas-chromatography mass-spectrometry. The rate of 13C enrichment, expressed as the increase of the fractional enrichment/min, was 0.0029 ± 0.0001/min in frequently seizing rats (n = 4; this was significantly higher (p < 0.01 than in the control (0.00167 ± 0.0001/min; n = 6 or in rats with infrequent seizures (0.00172 ± 0.0001/min; n = 6. This result strongly suggests that the flux of the excitatory neurotransmitter from neurons to the extracellular fluid is significantly increased by frequent seizures. The extracellular [12C + 13C]glutamate concentration increased progressively in frequently seizing rats. Taken together, these results strongly suggest that the observed seizure-induced high flux of glutamate overstimulated glutamate receptors, which triggered a chain reaction of excitation in the CA3 recurrent glutamatergic networks. The rate of 13C enrichment of extracellular glutamine (GLNECF at C5 was 0.00299 ± 0.00027/min in frequently seizing rats, which was higher (p < 0.05 than in controls (0.00227 ± 0.00008/min. For the first time in vivo, this study examined the effects of epileptic seizures on fluxes of the neurotransmitter glutamate and its precursor glutamine in the extracellular fluid of the hippocampus. The advantages, limitations and the potential for improvement of this approach for pre-clinical and clinical studies of temporal

  6. LONG-TERM HOMEOSTASIS OF EXTRACELLULAR GLUTAMATE IN THE RAT CEREBRAL CORTEX ACROSS SLEEP AND WAKING STATES

    OpenAIRE

    Dash, Michael B; Douglas, Christopher L.; Vyazovskiy, Vladyslav V.; Cirelli, Chiara; Tononi, Giulio

    2009-01-01

    Neuronal firing patterns, neuromodulators, and cerebral metabolism change across sleep waking states, and the synaptic release of glutamate is critically involved in these processes. Extrasynaptic glutamate can also affect neural function and may be neurotoxic, but whether and how extracellular glutamate is regulated across sleep-waking states is unclear. To assess the effect of behavioral state on extracellular glutamate at high temporal resolution, we recorded glutamate concentration in pre...

  7. Analysis of virion associated host proteins in vesicular stomatitis virus using a proteomics approach

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    Hwang Sun-Il

    2009-10-01

    Full Text Available Abstract Background Vesicular stomatitis virus (VSV is the prototypic rhabdovirus and the best studied member of the order Mononegavirales. There is now compelling evidence that enveloped virions released from infected cells carry numerous host (cellular proteins some of which may play an important role in viral replication. Although several cellular proteins have been previously shown to be incorporated into VSV virions, no systematic study has been done to reveal the host protein composition for virions of VSV or any other member of Mononegavirales. Results Here we used a proteomics approach to identify cellular proteins within purified VSV virions, thereby creating a "snapshot" of one stage of virus/host interaction that can guide future experiments aimed at understanding molecular mechanisms of virus-cell interactions. Highly purified preparations of VSV virions from three different cell lines of human, mouse and hamster origin were analyzed for the presence of cellular proteins using mass spectrometry. We have successfully confirmed the presence of several previously-identified cellular proteins within VSV virions and identified a number of additional proteins likely to also be present within the virions. In total, sixty-four cellular proteins were identified, of which nine were found in multiple preparations. A combination of immunoblotting and proteinase K protection assay was used to verify the presence of several of these proteins (integrin β1, heat shock protein 90 kDa, heat shock cognate 71 kDa protein, annexin 2, elongation factor 1a within the virions. Conclusion This is, to our knowledge, the first systematic study of the host protein composition for virions of VSV or any other member of the order Mononegavirales. Future experiments are needed to determine which of the identified proteins have an interaction with VSV and whether these interactions are beneficial, neutral or antiviral with respect to VSV replication. Identification

  8. (E)-[{sup 125}I]-5-AOIBV: a SPECT radioligand for the vesicular acetylcholine transporter

    Energy Technology Data Exchange (ETDEWEB)

    Emond, Patrick [INSERM U619, 37000 Tours (France); Universite Francois-Rabelais de Tours, CHRU, Hopital Bretonneau, Service de Medecine nucleaire, 37000 Tours (France); Mavel, Sylvie [INSERM U619, 37000 Tours (France); Universite Francois-Rabelais de Tours, CHRU, Hopital Bretonneau, Service de Medecine nucleaire, 37000 Tours (France)], E-mail: sylvie.mavel@univ-tours.fr; Zea-Ponce, Yolanda [INSERM U619, 37000 Tours (France); Universite Francois-Rabelais de Tours, CHRU, Hopital Bretonneau, Service de Medecine nucleaire, 37000 Tours (France); Kassiou, Michael [Discipline of Medical Radiation Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2050 (Australia); School of Chemistry, University of Sydney, NSW 2006 (Australia); Garreau, Lucette; Bodard, Sylvie; Drossard, Marie-Laure; Chalon, Sylvie; Guilloteau, Denis [INSERM U619, 37000 Tours (France); Universite Francois-Rabelais de Tours, CHRU, Hopital Bretonneau, Service de Medecine nucleaire, 37000 Tours (France)

    2007-11-15

    The premise that, over the course of Alzheimer's disease (AD), changes in the levels of the vesicular acetylcholine transporter (VAChT) occur in parallel with changes to other cholinergic marker proteins provides the basis for the applicability of benzovesamicol derivatives as radioligands for AD studies by single photon emission computed tomography or positron emission tomography. We report the synthesis of enantiopure benzovesamicol derivatives: (R,R) or (S,S)-(E)-2-hydroxy-5-(3-iodoprop-2-en-1-oxy)-3- (4-phenylpiperidino)tetralin [(R,R)-AOIBV: K{sub d}=0.45 nM or (S,S)-5-AOIBV: K{sub d}=4.3 nM] and their corresponding tributyltin precursors for radioiodination. (R,R or S,S)-5-AOIBV was labeled with iodine-125 from their corresponding n-tributyltin precursors. Both compounds were obtained with radiochemical and optical purity greater than 97% and in radiochemical yields ranging 34-36%. To determine if these compounds could provide an advantage when compared to [{sup 125}I]-iodo benzovesamicol (IBVM), IBVM was also labeled and used as the reference compound in all ex vivo experiments. Ex vivo biodistribution experiments in rats revealed that [{sup 125}I]-(R,R)-5-AOIBV displayed the most suitable pharmacological profile as the radioactivity distribution corresponded well with the known VAChT brain density. Moreover, pre-injection of vesamicol prevented the uptake of [{sup 125}I]-(R,R)-5-AOIBV in striatum, cortex and hippocampus, demonstrating selectivity for the VAChT. However, even if time activity curves of [{sup 125}I]-(R,R)-5-AOIBV confirmed that this compound could be used to visualize the VAChT in vivo, at each point of the kinetic study, [{sup 125}I]-(R,R)-5-AOIBV showed a lower specific binding compared to [{sup 125}I]-IBVM. These results made [{sup 125}I]-( R,R)-5-AOIBV inferior to [{sup 125}I]-IBVM for the VAChT exploration in vivo.

  9. Stimuli-Responsive Directional Vesicular Assembly with Tunable Surface Functionality and Impact on Enzyme Inhibition.

    Science.gov (United States)

    Sikder, Amrita; Ray, Debes; Aswal, Vinod K; Ghosh, Suhrit

    2017-08-08

    The article describes the self-assembly of a series of unsymmetrical bola-shaped π-amphiphiles (NDI-1, NDI-1a, NDI-2, NDI-3, and NDI-4) consisting of a hydrophobic naphthalene-diimide (NDI) chromophore attached to a nonionic hydrophilic wedge and an anionic headgroup in the two opposite arms of the central NDI. By design, only a single hydrazide group is linked either on the ionic or nonionic arm of the NDI. NDI-1 and NDI-1a are regioisomers differing only in the location of the hydrazide group, placed in the nonionic or ionic arm, respectively. NDI-2, NDI-3, and NDI-4 are similar to NDI-1 in the placement of the hydrazide group but differ in the nature of the ionic headgroups. Except for NDI-2, all of them exhibit spontaneous vesicle structures in water (pH 9.0) as established by electron microscopy, small-angle neutron scattering, dynamic light scattering, and spectroscopy studies. Supramolecularly assembled oligo-oxyethylene chains of the hydrophobic wedge exhibited a lower critical solution temperature (LCST) at ∼40 °C, similar to that of covalent polymers. Consequently, above the LCST, the bola-amphiphile was converted to a single headgroup surfactant, resulting in the collapse of the vesicular structure to nanoparticles. In all examples, the dominant H-bonding force among the hydrazide groups resulted in unidirectional orientation, leading to the formation of a nonsymmetric membrane with the H-bonded chain located at the inner wall. Therefore, the functional group displayed in these vesicles could be fully dictated by the location of the hydrazide group. Thus, for NDI-1, NDI-3, or NDI-4, the hydrazide group, located at the nonionic arm, directed the nonionic wedge to converge at the inner wall of the vesicle by displaying the anionic headgroups toward the outer surface. In contrast, NDI-1a formed a nonionic vesicle because in this case anionic headgroups were located at the inner wall of the membrane. Furthermore, among NDI-1, NDI-3, and NDI-4, the charge

  10. Ginsenoside Rd promotes glutamate clearance by up-regulating glial glutamate transporter GLT-1 via PI3K/AKT and ERK1/2 pathways.

    Science.gov (United States)

    Zhang, Xiao; Shi, Ming; Bjørås, Magnar; Wang, Wei; Zhang, Guangyun; Han, Junliang; Liu, Zhirong; Zhang, Yunxia; Wang, Bing; Chen, Jing; Zhu, Yi; Xiong, Lize; Zhao, Gang

    2013-01-01

    Ginsenoside Rd (Rd), one of the main active ingredients in Panax ginseng, has been showed to protect against ischemic cerebral damage both in vitro and in vivo. However, the underlying mechanism of Rd is largely unknown. Excessive extracellular glutamate causes excitatory toxicity, leading to cell death, and neurodegenerative processes after brain ischemia. The clearance of extracellular glutamate by astrocytic glutamate transporter GLT-1 is essential for neuronal survival after stroke. Here we investigated the effects of Rd on the levels of extracellular glutamate and the expression of GLT-1 in vivo and in vitro. After rat middle cerebral artery occlusion, Rd significantly increased the mRNA and protein expression levels of GLT-1, and reduced the burst of glutamate as revealed by microdialysis. Consistently, specific glutamate uptake by cultured astrocytes was elevated after Rd exposure. Furthermore, we showed that Rd increased the levels of phosphorylated protein kinase B (PKB/Akt) and phospho-ERK1/2 (p-ERK1/2) in astrocyte culture after oxygen-glucose deprivation. Moreover, the effect of Rd on GLT-1 expression and glutamate uptake can be abolished by PI3K/AKT agonist LY294002 or ERK1/2 inhibitor PD98059. Taken together, our findings provide the first evidence that Rd can promote glutamate clearance by up-regulating GLT-1 expression through PI3K/AKT and ERK1/2 pathways.

  11. Complete genome sequence of Bacillus amyloliquefaciens LL3, which exhibits glutamic acid-independent production of poly-γ-glutamic acid.

    Science.gov (United States)

    Geng, Weitao; Cao, Mingfeng; Song, Cunjiang; Xie, Hui; Liu, Li; Yang, Chao; Feng, Jun; Zhang, Wei; Jin, Yinghong; Du, Yang; Wang, Shufang

    2011-07-01

    Bacillus amyloliquefaciens is one of most prevalent Gram-positive aerobic spore-forming bacteria with the ability to synthesize polysaccharides and polypeptides. Here, we report the complete genome sequence of B. amyloliquefaciens LL3, which was isolated from fermented food and presents the glutamic acid-independent production of poly-γ-glutamic acid.

  12. Complete Genome Sequence of Bacillus amyloliquefaciens LL3, Which Exhibits Glutamic Acid-Independent Production of Poly-γ-Glutamic Acid▿

    OpenAIRE

    Geng, Weitao; Cao, Mingfeng; Song, Cunjiang; Xie, Hui; Liu, Li; Yang, Chao; Feng, Jun; Zhang, Wei; Jin, Yinghong; Du, Yang; Wang, Shufang

    2011-01-01

    Bacillus amyloliquefaciens is one of most prevalent Gram-positive aerobic spore-forming bacteria with the ability to synthesize polysaccharides and polypeptides. Here, we report the complete genome sequence of B. amyloliquefaciens LL3, which was isolated from fermented food and presents the glutamic acid-independent production of poly-γ-glutamic acid.

  13. Fast inhibition of glutamate-activated currents by caffeine.

    Directory of Open Access Journals (Sweden)

    Nicholas P Vyleta

    Full Text Available BACKGROUND: Caffeine stimulates calcium-induced calcium release (CICR in many cell types. In neurons, caffeine stimulates CICR presynaptically and thus modulates neurotransmitter release. METHODOLOGY/PRINCIPAL FINDINGS: Using the whole-cell patch-clamp technique we found that caffeine (20 mM reversibly increased the frequency and decreased the amplitude of miniature excitatory postsynaptic currents (mEPSCs in neocortical neurons. The increase in mEPSC frequency is consistent with a presynaptic mechanism. Caffeine also reduced exogenously applied glutamate-activated currents, confirming a separate postsynaptic action. This inhibition developed in tens of milliseconds, consistent with block of channel currents. Caffeine (20 mM did not reduce currents activated by exogenous NMDA, indicating that caffeine block is specific to non-NMDA type glutamate receptors. CONCLUSIONS/SIGNIFICANCE: Caffeine-induced inhibition of mEPSC amplitude occurs through postsynaptic block of non-NMDA type ionotropic glutamate receptors. Caffeine thus has both pre and postsynaptic sites of action at excitatory synapses.

  14. Crystal structure of a chimaeric bacterial glutamate dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Tânia; Sharkey, Michael A.; Engel, Paul C.; Khan, Amir R.

    2016-05-23

    Glutamate dehydrogenases (EC 1.4.1.2–4) catalyse the oxidative deamination of L-glutamate to α-ketoglutarate using NAD(P)+as a cofactor. The bacterial enzymes are hexameric, arranged with 32 symmetry, and each polypeptide consists of an N-terminal substrate-binding segment (domain I) followed by a C-terminal cofactor-binding segment (domain II). The catalytic reaction takes place in the cleft formed at the junction of the two domains. Distinct signature sequences in the nucleotide-binding domain have been linked to the binding of NAD+versusNADP+, but they are not unambiguous predictors of cofactor preference. In the absence of substrate, the two domains move apart as rigid bodies, as shown by the apo structure of glutamate dehydrogenase fromClostridium symbiosum. Here, the crystal structure of a chimaeric clostridial/Escherichia colienzyme has been determined in the apo state. The enzyme is fully functional and reveals possible determinants of interdomain flexibility at a hinge region following the pivot helix. The enzyme retains the preference for NADP+cofactor from the parentE. colidomain II, although there are subtle differences in catalytic activity.

  15. Targeting glutamate uptake to treat alcohol use disorders

    Directory of Open Access Journals (Sweden)

    P.S.S. eRao

    2015-04-01

    Full Text Available Alcoholism is a serious public health concern that is characterized by the development of tolerance to alcohol’s effects, increased consumption, loss of control over drinking and the development of physical dependence. This cycle is often times punctuated by periods of abstinence, craving and relapse. The development of tolerance and the expression of withdrawal effects, which manifest as dependence, have been to a great extent attributed to neuroadaptations within the mesocorticolimbic and extended amygdala systems. Alcohol affects various neurotransmitter systems in the brain including the adrenergic, cholinergic, dopaminergic, GABAergic, glutamatergic, peptidergic and serotonergic systems. Due to the myriad of neurotransmitter and neuromodulator systems affected by alcohol, the efficacies of current pharmacotherapies targeting alcohol dependence are limited. Importantly, research findings of changes in glutamatergic neurotransmission induced by alcohol self- or experimenter-administration have resulted in a focus on therapies targeting glutamatergic receptors and normalization of glutamatergic neurotransmission. Glutamatergic receptors implicated in the effects of ethanol include the ionotropic glutamate receptors (AMPA, Kainate, and NMDA and some metabotropic glutamate receptors. Regarding glutamatergic homeostasis, ceftriaxone, MS-153 and GPI-1046, which upregulate glutamate transporter 1 (GLT1 expression in mesocorticolimbic brain regions, reduce alcohol intake in genetic animal models of alcoholism. Given the hyperglutamatergic/hyperexcitable state of the central nervous system induced by chronic alcohol abuse and withdrawal, the evidence thus far indicates that a restoration of glutamatergic concentrations and activity within the mesocorticolimbic system and extended amygdala as well as multiple memory systems holds great promise for the treatment of alcohol dependence.

  16. Glutamate may be an efferent transmitter that elicits inhibition in mouse taste buds.

    Directory of Open Access Journals (Sweden)

    Yijen A Huang

    Full Text Available Recent studies suggest that l-glutamate may be an efferent transmitter released from axons innervating taste buds. In this report, we determined the types of ionotropic synaptic glutamate receptors present on taste cells and that underlie this postulated efferent transmission. We also studied what effect glutamate exerts on taste bud function. We isolated mouse taste buds and taste cells, conducted functional imaging using Fura 2, and used cellular biosensors to monitor taste-evoked transmitter release. The findings show that a large fraction of Presynaptic (Type III taste bud cells (∼50% respond to 100 µM glutamate, NMDA, or kainic acid (KA with an increase in intracellular Ca(2+. In contrast, Receptor (Type II taste cells rarely (4% responded to 100 µM glutamate. At this concentration and with these compounds, these agonists activate glutamatergic synaptic receptors, not glutamate taste (umami receptors. Moreover, applying glutamate, NMDA, or KA caused taste buds to secrete 5-HT, a Presynaptic taste cell transmitter, but not ATP, a Receptor cell transmitter. Indeed, glutamate-evoked 5-HT release inhibited taste-evoked ATP secretion. The findings are consistent with a role for glutamate in taste buds as an inhibitory efferent transmitter that acts via ionotropic synaptic glutamate receptors.

  17. Hierarchical mutational events compensate for glutamate auxotrophy of a Bacillus subtilis gltC mutant.

    Science.gov (United States)

    Dormeyer, Miriam; Lübke, Anastasia L; Müller, Peter; Lentes, Sabine; Reuß, Daniel R; Thürmer, Andrea; Stülke, Jörg; Daniel, Rolf; Brantl, Sabine; Commichau, Fabian M

    2017-06-01

    Glutamate is the major donor of nitrogen for anabolic reactions. The Gram-positive soil bacterium Bacillus subtilis either utilizes exogenously provided glutamate or synthesizes it using the gltAB-encoded glutamate synthase (GOGAT). In the absence of glutamate, the transcription factor GltC activates expression of the GOGAT genes for glutamate production. Consequently, a gltC mutant strain is auxotrophic for glutamate. Using a genetic selection and screening system, we could isolate and differentiate between gltC suppressor mutants in one step. All mutants had acquired the ability to synthesize glutamate, independent of GltC. We identified (i) gain-of-function mutations in the gltR gene, encoding the transcription factor GltR, (ii) mutations in the promoter of the gltAB operon and (iii) massive amplification of the genomic locus containing the gltAB operon. The mutants belonging to the first two classes constitutively expressed the gltAB genes and produced sufficient glutamate for growth. By contrast, mutants that belong to the third class appeared most frequently and solved glutamate limitation by increasing the copy number of the poorly expressed gltAB genes. Thus, glutamate auxotrophy of a B. subtilis gltC mutant can be relieved in multiple ways. Moreover, recombination-dependent amplification of the gltAB genes is the predominant mutational event indicating a hierarchy of mutations. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  18. A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

    Directory of Open Access Journals (Sweden)

    Bita Forghani

    2012-05-01

    Full Text Available L-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218 were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA as a bioactive compound.

  19. Morphine Protects Spinal Cord Astrocytes from Glutamate-Induced Apoptosis via Reducing Endoplasmic Reticulum Stress

    Directory of Open Access Journals (Sweden)

    Chao Zhang

    2016-10-01

    Full Text Available Glutamate is not only a neurotransmitter but also an important neurotoxin in central nervous system (CNS. Chronic elevation of glutamate induces both neuronal and glial cell apoptosis. However, its effect on astrocytes is complex and still remains unclear. In this study, we investigated whether morphine, a common opioid ligand, could affect glutamate-induced apoptosis in astrocytes. Primary cultured astrocytes were incubated with glutamate in the presence/absence of morphine. It was found that morphine could reduce glutamate-induced apoptosis of astrocytes. Furthermore, glutamate activated Ca2+ release, thereby inducing endoplasmic reticulum (ER stress in astrocytes, while morphine attenuated this deleterious effect. Using siRNA to reduce the expression of κ-opioid receptor, morphine could not effectively inhibit glutamate-stimulated Ca2+ release in astrocytes, the protective effect of morphine on glutamate-injured astrocytes was also suppressed. These results suggested that morphine could protect astrocytes from glutamate-induced apoptosis via reducing Ca2+ overload and ER stress pathways. In conclusion, this study indicated that excitotoxicity participated in the glutamate mediated apoptosis in astrocytes, while morphine attenuated this deleterious effect via regulating Ca2+ release and ER stress.

  20. A glutamic acid-producing lactic acid bacteria isolated from Malaysian fermented foods.

    Science.gov (United States)

    Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B; Saari, Nazamid

    2012-01-01

    l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound.

  1. A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

    Science.gov (United States)

    Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

    2012-01-01

    l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

  2. Glutamate-related gene expression changes with age in the mouse auditory midbrain.

    Science.gov (United States)

    Tadros, Sherif F; D'Souza, Mary; Zettel, Martha L; Zhu, Xiaoxia; Waxmonsky, Nicole C; Frisina, Robert D

    2007-01-05

    Glutamate is the main excitatory neurotransmitter in both the peripheral and central auditory systems. Changes of glutamate and glutamate-related genes with age may be an important factor in the pathogenesis of age-related hearing loss-presbycusis. In this study, changes in glutamate-related mRNA gene expression in the CBA mouse inferior colliculus with age and hearing loss were examined and correlations were sought between these changes and functional hearing measures, such as the auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAEs). Gene expression of 68 glutamate-related genes was investigated using both genechip microarray and real-time PCR (qPCR) molecular techniques for four different age/hearing loss CBA mouse subject groups. Two genes showed consistent differences between groups for both the genechip and qPCR. Pyrroline-5-carboxylate synthetase enzyme (Pycs) showed down-regulation with age and a high-affinity glutamate transporter (Slc1a3) showed up-regulation with age and hearing loss. Since Pycs plays a role in converting glutamate to proline, its deficiency in old age may lead to both glutamate increases and proline deficiencies in the auditory midbrain, playing a role in the subsequent inducement of glutamate toxicity and loss of proline neuroprotective effects. The up-regulation of Slc1a3 gene expression may reflect a cellular compensatory mechanism to protect against age-related glutamate or calcium excitoxicity.

  3. Glutamate-mediated protection of crayfish glial cells from PDT-induced apoptosis

    Science.gov (United States)

    Rudkovskii, M. V.; Romanenko, N. P.; Berezhnaya, E. V.; Kovaleva, V. D.; Uzdensky, A. B.

    2011-03-01

    Photodynamic treatment that causes intense oxidative stress and kills cells is currently used in neurooncology. However, along with tumor it damages surrounding healthy neurons and glial cells. In order to study the possible role of glutamate-related signaling pathways in photodynamic injury of neurons and glia, we investigated photodynamic effect of alumophthalocyanine Photosens on isolated crayfish stretch receptor that consists of a single neuron surrounded by glial cells. The laser diode (670 nm, 0.4 W/cm2) was used for dye photoexcitation. Application of glutamate increased photodynamically induced necrosis of neurons and glial cells but significantly decreased glial apoptosis. The natural neuroglial mediator N-acetylaspartylglutamate, which releases glutamate after cleavage in the extracellular space by glutamate carboxypeptidase II, also inhibited photoinduced apoptosis. Inhibition of glutamate carboxypeptidase II, oppositely, enhanced apoptosis of glial cells. These data confirm the anti-apoptotic activity of glutamate. Application of NMDA or inhibition of NMDA receptors by MK801 did not influence photodynamic death of neurons and glial cells that indicated nonparticipation of NMDA receptors in these processes. Inhibition of metabotropic glutamate receptors by AP-3 decreased PDT-induced apoptosis. One can suggest that crayfish neurons naturally secrete NAAG, which being cleaved by GCOP produces glutamate. Glutamate prevents photoinduced apoptosis of glial cells possibly through metabotropic but not ionotropic glutamate receptors.

  4. Glutamate and GABA-metabolizing enzymes in post-mortem cerebellum in Alzheimer's disease: phosphate-activated glutaminase and glutamic acid decarboxylase.

    Science.gov (United States)

    Burbaeva, G Sh; Boksha, I S; Tereshkina, E B; Savushkina, O K; Prokhorova, T A; Vorobyeva, E A

    2014-10-01

    Enzymes of glutamate and GABA metabolism in postmortem cerebellum from patients with Alzheimer's disease (AD) have not been comprehensively studied. The present work reports results of original comparative study on levels of phosphate-activated glutaminase (PAG) and glutamic acid decarboxylase isoenzymes (GAD65/67) in autopsied cerebellum samples from AD patients and matched controls (13 cases in each group) as well as summarizes published evidence for altered levels of PAG and GAD65/67 in AD brain. Altered (decreased) levels of these enzymes and changes in links between amounts of these enzymes and other glutamate-metabolizing enzymes (such as glutamate dehydrogenase and glutamine synthetase-like protein) in AD cerebella suggest significantly impaired glutamate and GABA metabolism in this brain region, which was previously regarded as not substantially involved in AD pathogenesis.

  5. New 4-Functionalized Glutamate Analogues Are Selective Agonists at Metabotropic Glutamate Receptor Subtype 2 or Selective Agonists at Metabotropic Glutamate Receptor Group III

    DEFF Research Database (Denmark)

    Huynh, Tri H. V.; Erichsen, Mette N.; Tora, Amelie S.

    2016-01-01

    The metabotropic glutamate (Glu) receptors (mGluRs) play key roles in modulating excitatory neurotransmission in the brain. In all, eight subtypes have been identified and divided into three groups, group I (mGlu1,5), group II (mGlu2,3), and group III (mGlu4,6–8). In this article, we present a L-...... a selective agonist activity profile at mGlu2 (EC50 in the micromolar range), whereas 2c/2d were both selective agonists at group III, subtypes mGlu4,6,8. In general, 2d was 20-fold more potent than 2c and potently activated mGlu4,6,8 in the low–mid nanomolar range.......The metabotropic glutamate (Glu) receptors (mGluRs) play key roles in modulating excitatory neurotransmission in the brain. In all, eight subtypes have been identified and divided into three groups, group I (mGlu1,5), group II (mGlu2,3), and group III (mGlu4,6–8). In this article, we present a L-2......,4-syn-substituted Glu analogue, 1d, which displays selective agonist activity at mGlu2 over the remaining mGluR subtypes. A modeling study and redesign of the core scaffold led to the stereoselective synthesis of four new conformationally restricted Glu analogues, 2a–d. Most interestingly, 2a retained...

  6. Delineation of glutamate pathways and secretory responses in pancreatic islets with β-cell-specific abrogation of the glutamate dehydrogenase

    DEFF Research Database (Denmark)

    Vetterli, Laurène; Carobbio, Stefania; Pournourmohammadi, Shirin

    2012-01-01

    In pancreatic β-cells, glutamate dehydrogenase (GDH) modulates insulin secretion, although its function regarding specific secretagogues is unclear. This study investigated the role of GDH using a β-cell-specific GDH knockout mouse model, called βGlud1(-/-). The absence of GDH in islets isolated...... from βGlud1(-/-) mice resulted in abrogation of insulin release evoked by glutamine combined with 2-aminobicyclo[2.2.1]heptane-2-carboxylic acid or l-leucine. Reintroduction of GDH in βGlud1(-/-) islets fully restored the secretory response. Regarding glucose stimulation, insulin secretion in islets...... isolated from βGlud1(-/-) mice exhibited half of the response measured in control islets. The amplifying pathway, tested at stimulatory glucose concentrations in the presence of KCl and diazoxide, was markedly inhibited in βGlud1(-/-) islets. On glucose stimulation, net synthesis of glutamate from α...

  7. Synthesis and in vitro pharmacology at AMPA and kainate preferring glutamate receptors of 4-heteroarylmethylidene glutamate analogues

    DEFF Research Database (Denmark)

    Valgeirsson, Jon; Christensen, Jeppe K; Kristensen, Anders S

    2003-01-01

    2-Amino-3-[3-hydroxy-5-(2-thiazolyl)-4-isoxazolyl]propionic acid (1) is a potent AMPA receptor agonist with moderate affinity for native kainic acid (KA) receptors, whereas (S)-E-4-(2,2-dimethylpropylidene)glutamic acid (3) show high affinity for the GluR5 subtype of KA receptors and much lower...... affinity for the GluR2 subtype of AMPA receptors. As an attempt to develop new pharmacological tools for studies of GluR5 receptors, (S)-E-4-(2-thiazolylmethylene)glutamic acid (4a) was designed as a structural hybrid between 1 and 3. 4a was shown to be a potent GluR5 agonist and a high affinity ligand...

  8. Cationic amino acid transporter 2 enhances innate immunity during Helicobacter pylori infection.

    Directory of Open Access Journals (Sweden)

    Daniel P Barry

    Full Text Available Once acquired, Helicobacter pylori infection is lifelong due to an inadequate innate and adaptive immune response. Our previous studies indicate that interactions among the various pathways of arginine metabolism in the host are critical determinants of outcomes following infection. Cationic amino acid transporter 2 (CAT2 is essential for transport of L-arginine (L-Arg into monocytic immune cells during H. pylori infection. Once within the cell, this amino acid is utilized by opposing pathways that lead to elaboration of either bactericidal nitric oxide (NO produced from inducible NO synthase (iNOS, or hydrogen peroxide, which causes macrophage apoptosis, via arginase and the polyamine pathway. Because of its central role in controlling L-Arg availability in macrophages, we investigated the importance of CAT2 in vivo during H. pylori infection. CAT2(-/- mice infected for 4 months exhibited decreased gastritis and increased levels of colonization compared to wild type mice. We observed suppression of gastric macrophage levels, macrophage expression of iNOS, dendritic cell activation, and expression of granulocyte-colony stimulating factor in CAT2(-/- mice suggesting that CAT2 is involved in enhancing the innate immune response. In addition, cytokine expression in CAT2(-/- mice was altered from an antimicrobial Th1 response to a Th2 response, indicating that the transporter has downstream effects on adaptive immunity as well. These findings demonstrate that CAT2 is an important regulator of the immune response during H. pylori infection.

  9. Sodium-glucose co-transporter-2 inhibitors and euglycemic ketoacidosis: Wisdom of hindsight

    Directory of Open Access Journals (Sweden)

    Awadhesh Kumar Singh

    2015-01-01

    Full Text Available Sodium-glucose co-transporter-2 inhibitors (SGLT-2i are newly approved class of oral anti-diabetic drugs, in the treatment of type 2 diabetes, which reduces blood glucose through glucouresis via the kidney, independent, and irrespective of available pancreatic beta-cells. Studies conducted across their clinical development program found, a modest reduction in glycated hemoglobin ranging from −0.5 to −0.8%, without any significant hypoglycemia. Moreover, head-to-head studies versus active comparators yielded comparable efficacy. Interestingly, weight and blood pressure reduction were additionally observed, which was not only consistent but significantly superior to active comparators, including metformin, sulfonylureas, and dipeptydylpeptide-4 inhibitors. Indeed, these additional properties makes this class a promising oral anti-diabetic drug. Surprisingly, a potentially fatal unwanted side effect of diabetic ketoacidosis has been noted with its widespread use, albeit rarely. Nevertheless, this has created a passé among the clinicians. This review is an attempt to pool those ketosis data emerging with SGLT-2i, and put a perspective on its implicated mechanism.

  10. Energy balance and metabolic changes with sodium-glucose co-transporter 2 inhibition.

    Science.gov (United States)

    Rajeev, S P; Cuthbertson, D J; Wilding, J P H

    2016-02-01

    Sodium-glucose co-transporter 2 (SGLT2) inhibitors are the latest addition to the class of oral glucose-lowering drugs. They have been rapidly adopted into clinical practice because of therapeutic advantages, including weight loss and reduction in blood pressure, in addition to glycaemic benefits and a low intrinsic risk of hypoglycaemia. Although there are extensive data on the clinical effects of SGLT2 inhibition, the metabolic effects of inhibiting renal glucose reabsorption have not been fully described. Recent studies have identified compensatory metabolic effects, such as an increase in endogenous glucose production, and have also shown an increase in glucagon secretion during SGLT2 inhibition. In addition, there is a discrepancy between the expected and observed weight loss found in clinical studies on SGLT2 inhibitors, probably as a result of changes in energy balance with this treatment approach. SGLT2 inhibition is likely to have intriguing effects on whole body metabolism which have not been fully elucidated, and which, if explained, might help optimize the use of this new class of medicines. © 2015 John Wiley & Sons Ltd.

  11. Mecanismos moleculares de resistencia a las enfermedades vesiculares virales del ganado criollo colombiano blanco orejinegro (BON

    Directory of Open Access Journals (Sweden)

    Jorge Eliécer Ossa Londoño

    2001-04-01

    Full Text Available

    En Colombia circulan dos virus que producen enfermedad vesicular en bovinos: Fiebre Aftosa (VFA y Estomatitis Vesicular (VEV. El genoma de estos es ssRNA, el cual durante la replicación da lugar a dsRNA, que es el más potente inductor de interferón (IFN tipo I

  12. Glutamate modulators as novel interventions for mood disorders Moduladores de glutamato como novas intervenções em transtornos do humor

    Directory of Open Access Journals (Sweden)

    Sanjay J Mathew

    2005-09-01

    Full Text Available Recent evidence suggests that critical molecules in neurotrophic signaling cascades are long-term targets for currently available monoaminergic antidepressants. As chronic and severe mood disorders are characterized by impairments in neuronal resilience, pharmacological strategies that subserve a neuroprotective function might alter disorder pathophysiology and modify disease progression. Several promising approaches involve modulation of the glutamate neurotransmitter system, via post-synaptic receptor blockade or potentiation and presynaptic vesicular release inhibition. A focused review of the extant scientific literature was conducted, with a discussion of 3 compounds or classes of drugs currently undergoing clinical investigation: ketamine, riluzole, and AMPA receptor potentiators. Recent investigations in mood disordered patients suggest that the NMDA receptor antagonist ketamine might demonstrate rapid antidepressant properties. Riluzole has been shown to reverse glutamate-mediated impairments in neuronal plasticity and to stimulate the synthesis of brain derived neurotrophic factor. Open-label trials in treatment-resistant depression have yielded promising results. Likewise, AMPA receptor potentiators favorably impact neurotrophic factors as well as enhance cognition. CONCLUSIONS: Pharmacological approaches that modulate components of the glutamate system offer novel targets for severe, recurrent mood disorders. Controlled studies are necessary.Recentes evidências sugerem que as moléculas críticas nas cascatas de sinalização neurotrófica são alvos de longo prazo dos antidepressivos monoaminérgicos disponíveis atualmente. Na medida em que transtornos graves e crônicos são caracterizados por deficiências na resiliência neuronal, estratégias farmacológicas que sejam úteis para uma função neuroprotetora talvez possam alterar a fisiopatologia e modificar a progressão da doença. Vários enfoques promissores envolvem a

  13. Reduced expression of glutamate transporter EAAT2 and impaired glutamate transport in human primary astrocytes exposed to HIV-1 or gp120.

    Science.gov (United States)

    Wang, Zhuying; Pekarskaya, Olga; Bencheikh, Meryem; Chao, Wei; Gelbard, Harris A; Ghorpade, Anuja; Rothstein, Jeffrey D; Volsky, David J

    2003-07-20

    L-Glutamate is the major excitatory neurotransmitter in the brain. Astrocytes maintain low levels of synaptic glutamate by high-affinity uptake and defects in this function may lead to neuronal cell death by excitotoxicity. We tested the effects of HIV-1 and its envelope glycoprotein gp120 upon glutamate uptake and expression of glutamate transporters EAAT1 and EAAT2 in fetal human astrocytes in vitro. Astrocytes isolated from fetal tissues between 16 and 19 weeks of gestation expressed EAAT1 and EAAT2 RNA and proteins as detected by Northern blot analysis and immunoblotting, respectively, and the cells were capable of specific glutamate uptake. Exposure of astrocytes to HIV-1 or gp120 significantly impaired glutamate uptake by the cells, with maximum inhibition within 6 h, followed by gradual decline during 3 days of observation. HIV-1-infected cells showed a 59% reduction in V(max) for glutamate transport, indicating a reduction in the number of active transporter sites on the cell surface. Impaired glutamate transport after HIV-1 infection or gp120 exposure correlated with a 40-70% decline in steady-state levels of EAAT2 RNA and protein. EAAT1 RNA and protein levels were less affected. Treatment of astrocytes with tumor necrosis factor-alpha (TNF-alpha) decreased the expression of both EAAT1 and EAAT2, but neither HIV-1 nor gp120 were found to induce TNF-alpha production by astrocytes. These findings demonstrate that HIV-1 and gp120 induce transcriptional downmodulation of the EAAT2 transporter gene in human astrocytes and coordinately attenuate glutamate transport by the cells. Reduction of the ability of HIV-1-infected astrocytes to take up glutamate may contribute to the development of neurological disease.

  14. Effects of microwave exposure on the hamster immune system. III. Macrophage resistance to vesicular stomatitis virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Rao, G.R.; Cain, C.A.; Tompkins, W.A.

    1984-01-01

    Exposure of hamsters to microwave (MW) energy (2.45 GHz, 25 mW/cm2, 1 h) resulted in activation of peritoneal macrophages (PM) to a viricidal state restricting the replication of vesicular stomatitis virus (VSV). The PM from MW-exposed hamsters were viricidal as early as 1 day after exposure and remained active for 5 days. Immunization of hamsters with vaccinia virus induced viricidal PM by 3 to 4 days and they remained active for 7 days. To test the hypothesis that thermogenic MW exposure results in the release of endotoxin across the intestinal epithelium which subsequently activates PM, hamsters were injected with lipopolysaccharide (LPS) and their viricidal activity was studied. Lipopolysaccharide in vitro (0.2 microgram) and in vivo (0.5 microgram) activated macrophages to a viricidal state. When administered in vivo, LPS (0.5 microgram) activated macrophages as early as 1 day and the activity remained for 3 days. While MW exposure of PM in vitro failed to induce viricidal activity, exposure of PM to LPS in vitro induced strong viricidal activity. This suggests that the in vivo response of PM to MW is an indirect one, which is consistent with the hypothesis that MW-induced PM viricidal activity may be mediated via LPS. In preliminary experiments, MW exposure resulted in extended survival time for hamsters challenged with a lethal dose of vesicular stomatitis virus, supporting the concept that MW-activated PM may be a useful therapeutic modality.

  15. Didelphis marsupialis como un reservorio potencial u hospedero amplificador del virus de la estomatitis vesicular, serotipo new jersey en Antioquia

    Directory of Open Access Journals (Sweden)

    John Arboleda

    2004-02-01

    Full Text Available

    La Estomatitis Vesicular (EV es una enfermedad viral, aguda
    y autolimitante que afecta principalmente bovinos, equinos y
    porcinos. Es producida por el virus de estomatitis vesicular (VEV, serotipos New Jersey (VEV-NJ e Indiana (VEV-IN, que son los as importantes epidemiológicamente (1. Los estudios serológicos demuestran que VEV-NJ y VEV-IN infectan en forma natural una gran variedad de animales silvestres, que están posiblemente implicados en la  coepizootiología de la EV, como hospederos portadores, mplificadores o reservorios (2.

    La zarigüeya (Didelphis marsupialis es un buen candidato
    para cumplir esta función, debido a que es la especie silvestre
    mayormente capturada en zonas enzoóticas; presenta altos
    porcentajes de infección natural (3, resiste la antropización y
    además, su comportamiento le permite interactuar con
    diferentes poblaciones de vectores u otros reservorios en los
    bosques y servir como fuente de infección para las especies
    domésticas susceptibles.

     

     

  16. Protective effect of naringenin on glutamate-induced neurotoxicity in cultured hippocampal cells

    Directory of Open Access Journals (Sweden)

    Xu Xiao-Hui

    2015-01-01

    Full Text Available Monosodium glutamate induces excitotoxicity in the central nervous system through hyperactivation of both ionotropic and metabotropic glutamate receptors, which leads to neuronal cell death. In this study, we investigated the neuroprotective effects of naringenin on excitotoxicity induced by glutamate in primary hippocampal neurons of neonatal mice. The expression levels of apoptosis-inducing proteins and as well as ischemic factors were observed by Western blot analysis. Immunocytochemistry and morphometric analysis of hippocampal cells with or without glutamate and naringenin treatment were performed. We observed that naringenin regulated Erk1/2 and Akt phosphorylation and reduced the demise of dendrites due to glutamate exposure in cultured hippocampal neurons. Furthermore, naringenin induced the brain-derived neurotrophic factor and other neuroprotective cytokines, and markedly improved the survival rates of the neurons 24 h following glutamate exposure. The observed results suggest that the naturally occurring bioflavonoid (naringenin exerts neuroprotective effects via highly specific molecular targets in neurons.

  17. Exogenous glutamate induces short and long-term potentiation in the rat medial vestibular nuclei.

    Science.gov (United States)

    Grassi, S; Frondaroli, A; Pessia, M; Pettorossi, V E

    2001-08-08

    In rat brain stem slices, high concentrations of exogenous glutamate induce long-term potentiation (LTP) of the field potentials evoked in the medial vestibular nuclei (MVN) by vestibular afferent stimulation. At low concentrations, glutamate can also induce short-term potentiation (STP), indicating that LTP and STP are separate events depending on the level of glutamatergic synapse activation. LTP and STP are prevented by blocking NMDA receptors and nitric oxide (NO) synthesis. Conversely, blocking platelet-activating factor (PAF) and group I metabotropic glutamate receptors only prevents the full development of LTP. Moreover, in the presence of blocking agents, glutamate causes transient inhibition, suggesting that when potentiation is impeded, exogenous glutamate can activate presynaptic mechanisms that reduce glutamate release.

  18. Dual Effects of TARP γ-2 on Glutamate Efficacy Can Account for AMPA Receptor Autoinactivation

    Directory of Open Access Journals (Sweden)

    Ian D. Coombs

    2017-08-01

    Full Text Available Fast excitatory transmission in the CNS is mediated mainly by AMPA-type glutamate receptors (AMPARs associated with transmembrane AMPAR regulatory proteins (TARPs. At the high glutamate concentrations typically seen during synaptic transmission, TARPs slow receptor desensitization and enhance mean channel conductance. However, their influence on channels gated by low glutamate concentrations, as encountered during delayed transmitter clearance or synaptic spillover, is poorly understood. We report here that TARP γ-2 reduces the ability of low glutamate concentrations to cause AMPAR desensitization and enhances channel gating at low glutamate occupancy. Simulations show that, by shifting the balance between AMPAR activation and desensitization, TARPs can markedly facilitate the transduction of spillover-mediated synaptic signaling. Furthermore, the dual effects of TARPs can account for biphasic steady-state glutamate concentration-response curves—a phenomenon termed “autoinactivation,” previously thought to reflect desensitization-mediated AMPAR/TARP dissociation.

  19. Effect of diphenylthiocarbazone (dithizone) on glutamate level in hippocampus preparation in vitro and in vivo.

    Science.gov (United States)

    Kihara, T; Ishihara, T; Baba, A; Iwata, H

    1990-04-01

    To assess the functional interaction between Zn2+ and glutamate in hippocampus, diphenylthiocarbazone (dithizone), a Zn2+ chelator, was used to alter the glutamate level in hippocampus in vitro and in vivo. Dithizone at the concentration of 1 microM stimulated high K(+)- and veratrine-induced release of [3H]glutamate both in the presence and absence of Ca2+ from rat hippocampal slices preloaded with [3H]glutamate without affecting the release of [3H]gamma-aminobutyric acid and [3H]acetylcholine. Metal chelators other than dithizone did not evoke the [3H]glutamate release at the concentration of 10 microM. Two weeks after the intrahippocampal injection of 20 micrograms of dithizone, both Zn2+ and glutamate levels of the hippocampus significantly decreased with no change in the levels of other metals, amino acids, monoamines and acetylcholine.

  20. Development of a novel ultrasensitive enzyme immunoassay for human glutamic acid decarboxylase 65 antibody.

    Science.gov (United States)

    Numata, Satoshi; Katakami, Hideki; Inoue, Shinobu; Sawada, Hirotake; Hashida, Seiichi

    2016-07-01

    We developed a novel, ultrasensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) for determination of glutamic acid decarboxylase autoantibody concentrations in serum samples from patients with type 2 diabetes. We developed an immune complex transfer enzyme immunoassay for glutamic acid decarboxylase autoantibody and measured glutamic acid decarboxylase autoantibody from 22 patients with type 1 diabetes, 29 patients with type 2 diabetes, and 32 healthy controls. A conventional ELISA kit identified 10 patients with type 1 diabetes and one patient with type 2 diabetes as glutamic acid decarboxylase autoantibody positive, whereas 15 patients with type 1 diabetes and six patients with type 2 diabetes were identified as glutamic acid decarboxylase autoantibody positive using immune complex transfer enzyme immunoassay. Immune complex transfer enzyme immunoassay is a highly sensitive and specific assay for glutamic acid decarboxylase autoantibody and might be clinically useful for diabetic onset prediction and early diagnosis. © The Author(s) 2016.