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Sample records for targeted-replacement mice overexpressing

  1. Apolipoprotein E-specific innate immune response in astrocytes from targeted replacement mice

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    Montine Thomas J

    2006-04-01

    Full Text Available Abstract Background Inheritance of the three different alleles of the human apolipoprotein (apo E gene (APOE are associated with varying risk or clinical outcome from a variety of neurologic diseases. ApoE isoform-specific modulation of several pathogenic processes, in addition to amyloid β metabolism in Alzheimer's disease, have been proposed: one of these is innate immune response by glia. Previously we have shown that primary microglia cultures from targeted replacement (TR APOE mice have apoE isoform-dependent innate immune activation and paracrine damage to neurons that is greatest with TR by the ε4 allele (TR APOE4 and that derives from p38 mitogen-activated protein kinase (p38MAPK activity. Methods Primary cultures of TR APOE2, TR APOE3 and TR APOE4 astrocytes were stimulated with lipopolysaccharide (LPS. ApoE secretion, cytokine production, and nuclear factor-kappa B (NF-κB subunit activity were measured and compared. Results Here we showed that activation of primary astrocytes from TR APOE mice with LPS led to TR APOE-dependent differences in cytokine secretion that were greatest in TR APOE2 and that were associated with differences in NF-κB subunit activity. Conclusion Our results suggest that LPS activation of innate immune response in TR APOE glia results in opposing outcomes from microglia and astrocytes as a result of TR APOE-dependent activation of p38MAPK or NF-κB signaling in these two cell types.

  2. Reduced phosphorylation of brain insulin receptor substrate and Akt proteins in apolipoprotein-E4 targeted replacement mice.

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    Ong, Qi-Rui; Chan, Elizabeth S; Lim, Mei-Li; Cole, Gregory M; Wong, Boon-Seng

    2014-01-17

    Human ApoE4 accelerates memory decline in ageing and in Alzheimer's disease. Although intranasal insulin can improve cognition, this has little effect in ApoE4 subjects. To understand this ApoE genotype-dependent effect, we examined brain insulin signaling in huApoE3 and huApoE4 targeted replacement (TR) mice. At 32 weeks, lower insulin receptor substrate 1 (IRS1) at S636/639 and Akt phosphorylation at T308 were detected in fasting huApoE4 TR mice as compared to fasting huApoE3 TR mice. These changes in fasting huApoE4 TR mice were linked to lower brain glucose content and have no effect on plasma glucose level. However, at 72 weeks of age, these early changes were accompanied by reduction in IRS2 expression, IRS1 phosphorylation at Y608, Akt phosphorylation at S473, and MAPK (p38 and p44/42) activation in the fasting huApoE4 TR mice. The lower brain glucose was significantly associated with higher brain insulin in the aged huApoE4 TR mice. These results show that ApoE4 reduces brain insulin signaling and glucose level leading to higher insulin content.

  3. Neuroglobin-overexpression reduces traumatic brain lesion size in mice

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    Zhao Song

    2012-06-01

    Full Text Available Abstract Background Accumulating evidence has demonstrated that over-expression of Neuroglobin (Ngb is neuroprotective against hypoxic/ischemic brain injuries. In this study we tested the neuroprotective effects of Ngb over-expression against traumatic brain injury (TBI in mice. Results Both Ngb over-expression transgenic (Ngb-Tg and wild-type (WT control mice were subjected to TBI induced by a controlled cortical impact (CCI device. TBI significantly increased Ngb expression in the brains of both WT and Ngb-Tg mice, but Ngb-Tg mice had significantly higher Ngb protein levels at the pre-injury baseline and post-TBI. Production of oxidative tissue damage biomarker 3NT in the brain was significantly reduced in Ngb-Tg mice compared to WT controls at 6 hours after TBI. The traumatic brain lesion volume was significantly reduced in Ngb Tg mice compared to WT mice at 3 weeks after TBI; however, there were no significant differences in the recovery of sensorimotor and spatial memory functional deficits between Ngb-Tg and WT control mice for up to 3 weeks after TBI. Conclusion Ngb over-expression reduced traumatic lesion volume, which might partially be achieved by decreasing oxidative stress.

  4. Young APOE[subscript 4] Targeted Replacement Mice Exhibit Poor Spatial Learning and Memory, with Reduced Dendritic Spine Density in the Medial Entorhinal Cortex

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    Rodriguez, Gustavo A.; Burns, Mark P.; Weeber, Edwin J.; Rebeck, G. William

    2013-01-01

    The apolipoprotein E4 ("APOE-[epsilon]4") allele is the strongest genetic risk factor for developing late-onset Alzheimer's disease, and may predispose individuals to Alzheimer's-related cognitive decline by affecting normal brain function early in life. To investigate the impact of human APOE alleles on cognitive performance in mice, we trained…

  5. Brain phenotype of transgenic mice overexpressing cystathionine β-synthase.

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    Vinciane Régnier

    Full Text Available The cystathionine β-synthase (CBS gene, located on human chromosome 21q22.3, is a good candidate for playing a role in the Down Syndrome (DS cognitive profile: it is overexpressed in the brain of individuals with DS, and it encodes a key enzyme of sulfur-containing amino acid (SAA metabolism, a pathway important for several brain physiological processes.Here, we have studied the neural consequences of CBS overexpression in a transgenic mouse line (60.4P102D1 expressing the human CBS gene under the control of its endogenous regulatory regions. These mice displayed a ∼2-fold increase in total CBS proteins in different brain areas and a ∼1.3-fold increase in CBS activity in the cerebellum and the hippocampus. No major disturbance of SAA metabolism was observed, and the transgenic mice showed normal behavior in the rotarod and passive avoidance tests. However, we found that hippocampal synaptic plasticity is facilitated in the 60.4P102D1 line.We demonstrate that CBS overexpression has functional consequences on hippocampal neuronal networks. These results shed new light on the function of the CBS gene, and raise the interesting possibility that CBS overexpression might have an advantageous effect on some cognitive functions in DS.

  6. Tubular overexpression of gremlin induces renal damage susceptibility in mice.

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    Alejandra Droguett

    Full Text Available A growing number of patients are recognized worldwide to have chronic kidney disease. Glomerular and interstitial fibrosis are hallmarks of renal progression. However, fibrosis of the kidney remains an unresolved challenge, and its molecular mechanisms are still not fully understood. Gremlin is an embryogenic gene that has been shown to play a key role in nephrogenesis, and its expression is generally low in the normal adult kidney. However, gremlin expression is elevated in many human renal diseases, including diabetic nephropathy, pauci-immune glomerulonephritis and chronic allograft nephropathy. Several studies have proposed that gremlin may be involved in renal damage by acting as a downstream mediator of TGF-β. To examine the in vivo role of gremlin in kidney pathophysiology, we generated seven viable transgenic mouse lines expressing human gremlin (GREM1 specifically in renal proximal tubular epithelial cells under the control of an androgen-regulated promoter. These lines demonstrated 1.2- to 200-fold increased GREM1 expression. GREM1 transgenic mice presented a normal phenotype and were without proteinuria and renal function involvement. In response to the acute renal damage cause by folic acid nephrotoxicity, tubule-specific GREM1 transgenic mice developed increased proteinuria after 7 and 14 days compared with wild-type treated mice. At 14 days tubular lesions, such as dilatation, epithelium flattening and hyaline casts, with interstitial cell infiltration and mild fibrosis were significantly more prominent in transgenic mice than wild-type mice. Tubular GREM1 overexpression was correlated with the renal upregulation of profibrotic factors, such as TGF-β and αSMA, and with increased numbers of monocytes/macrophages and lymphocytes compared to wild-type mice. Taken together, our results suggest that GREM1-overexpressing mice have an increased susceptibility to renal damage, supporting the involvement of gremlin in renal damage

  7. Mammary gland tumor formation in transgenic mice overexpressing stromelysin-1

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    Sympson, Carolyn J; Bissell, Mina J; Werb, Zena

    1995-06-01

    An intact basement membrane (BM) is essential for the proper function, differentiation and morphology of many epithelial cells. The disruption or loss of this BM occurs during normal development as well as in the disease state. To examine the importance of BM during mammary gland development in vivo, we generated transgenic mice that inappropriately express autoactivating isoforms of the matrix metalloproteinase stromelysin-1. The mammary glands from these mice are both functionally and morphologically altered throughout development. We have now documented a dramatic incidence of breast tumors in several independent lines of these mice. These data suggest that overexpression of stromelysin-1 and disruption of the BM may be a key step in the multi-step process of breast cancer.

  8. Impaired baroreflex function in mice overexpressing alpha-synuclein

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    Sheila eFleming

    2013-07-01

    Full Text Available Cardiovascular autonomic dysfunction, such as orthostatic hypotension consequent to baroreflex failure and cardiac sympathetic denervation, is frequently observed in the synucleinopathy Parkinson’s disease (PD. In the present study, the baroreceptor reflex was assessed in mice overexpressing human wildtype alpha-synuclein (Thy1-aSyn, a genetic mouse model of synucleinopathy. The beat-to-beat change in heart rate, computed from R-R interval, in relation to blood pressure was measured in anesthetized and conscious mice equipped with arterial blood pressure telemetry transducers during transient bouts of hypertension and hypotension. Compared to wildtype, tachycardia following nitroprusside-induced hypotension was significantly reduced in Thy1-aSyn mice. Thy1-aSyn mice also showed an abnormal cardiovascular response (i.e., diminished tachycardia to muscarinic blockade with atropine. We conclude that Thy1-aSyn mice have impaired basal and dynamic range of sympathetic and parasympathetic-mediated changes in heart rate and will be a useful model for long-term study of cardiovascular autonomic dysfunction associated with PD.

  9. ADAM12 overexpression does not improve outcome in mice with laminin alpha2-deficient muscular dystrophy

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    Guo, Ling T; Shelton, G Diane; Wewer, Ulla M

    2005-01-01

    We have recently shown that overexpression of ADAM12 results in increased muscle regeneration and significantly reduced pathology in mdx, dystrophin deficient mice. In the present study, we tested the effect of overexpressing ADAM12 in dy(W) laminin-deficient mice. dy mice have a very severe...... clinical phenotype and would be expected to benefit greatly from enhanced regeneration. We found that dy(W) mice overexpressing ADAM12 indeed have increased muscle regeneration, as evidenced by increased numbers of muscle fibers expressing fetal myosin. However, overexpression of ADAM12 had no significant...

  10. Protection against vascular leak in neprilysin transgenic mice with complex overexpression pattern.

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    Wick, Marilee J; Loomis, Zoe L; Harral, Julie W; Le, Mysan; Wehling, Carol A; Miller, York E; Dempsey, Edward C

    2016-12-01

    Neprilysin (NEP) is a cell surface metallopeptidase found in many tissues. Based mostly on pharmacological manipulations, NEP has been thought to protect blood vessels from plasma extravasation. We have suggested that NEP may protect against pulmonary vascular injury. However, these prior studies did not utilize mice which overexpress NEP. The aims of the present investigation were to develop and characterize doubly transgenic (DT) mice that overexpress NEP universally and conditionally, and to investigate the protective effect that overexpressed NEP may have against plasma extravasation in the vasculature. The duodenum, which is often used to assess vascular permeability, and in which the NEP protein was overexpressed in our DT mice two-fold, was selected as our experimental preparation. We found that substance P-induced plasma extravasation was decreased substantially (3.5-fold) in the duodenums of our doxycycline-treated DT mice, giving independent evidence of NEP's protective effects against plasma extravasation. Transgenic lung NEP protein was not stably expressed in the DT mice, so we were not able to test the effect of NEP overexpression in the lung. Although initially overexpressed nearly nine-fold at that site, pulmonary NEP protein overexpression eventually dissipated. Surprisingly, at a time when there was no lung transgenic NEP protein overexpression, lung NEP mRNA expression was still increased 23-fold, indicating that the expression defect probably is not transcriptional. These studies help to characterize our complex transgenic model of NEP overexpression and further demonstrate NEP's protective effects against plasma extravasation.

  11. Overexpression of mineralocorticoid receptors does not affect memory and anxiety-like behavior in female mice

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    Sofia eKanatsou

    2015-07-01

    Full Text Available Mineralocorticoid receptors (MRs have been implicated in behavioral adaptation and learning and memory. Since – at least in humans - MR function seems to be sex-dependent, we examined the behavioral relevance of MR in female mice exhibiting transgenic MR overexpression in the forebrain. Transgenic MR overexpression did not affect contextual fear memory or cued fear learning and memory. Moreover, MR overexpressing and control mice discriminated equally well between fear responses in a combined cue and context fear conditioning paradigm. Also context-memory in an object recognition task was unaffected in MR overexpressing mice. We conclude that MR overexpression in female animals does not affect fear conditioned responses and object recognition memory.

  12. Exacerbation of collagen antibody-induced arthritis in transgenic mice overexpressing peroxiredoxin 6.

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    Kim, Dae Hwan; Lee, Dong Hun; Jo, Mi Ran; Son, Dong Ju; Park, Mi Hee; Hwang, Chul Ju; Park, Ju Ho; Yuk, Dong Yeon; Yoon, Do Young; Jung, Young-Suk; Kim, Youngsoo; Jeong, Jae Hwang; Han, Sang Bae; Hong, Jin Tae

    2015-11-01

    Peroxiredoxin 6 plays important and complex roles in the process of inflammation, but its role in the development of rheumatoid arthritis (RA) remains unclear. We undertook this study to investigate the roles and mechanisms of peroxiredoxin 6 in the development of collagen antibody-induced arthritis (CAIA) and antigen-induced arthritis (AIA) in peroxiredoxin 6-overexpressing transgenic mice, in peroxiredoxin 6-transfected RAW 264.7 cells, in macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and in synoviocytes from arthritis patients. CAIA and AIA were induced using standard methods. Peroxiredoxin 6-transfected RAW 264.7 cells, macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and synoviocytes from arthritis patients were used to study proinflammatory responses and mechanisms. Clinical scores and histopathologic changes were determined in peroxiredoxin 6-overexpressing transgenic mice and wild-type (WT) mice with CAIA or AIA. Generation of nitric oxide (NO), expression of inducible NO synthase and cyclooxygenase 2, and activity of NF-κB and activator protein 1 (AP-1) were determined in cultured macrophages and synoviocytes as well as in joint tissue from mice by Western blotting, electrophoretic mobility shift assay, and immunohistochemical analysis. Development of CAIA and AIA and proinflammatory responses were more exacerbated in peroxiredoxin 6-overexpressing transgenic mice than in WT mice. Overexpression of peroxiredoxin 6 increased lipopolysaccharide-induced inflammatory responses in RAW 264.7 cells, in macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and in synoviocytes from arthritis patients, and this was accompanied by up-regulation of the JNK pathway. Moreover, a JNK inhibitor completely blocked RA development and proinflammatory responses. Our findings suggest that overexpression of peroxiredoxin 6 might promote development of RA through NF-κB and AP-1 activity via the JNK

  13. Effects of Mineralocorticoid Receptor Overexpression on Anxiety and Memory after Early Life Stress in Female Mice.

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    Kanatsou, Sofia; Ter Horst, Judith P; Harris, Anjanette P; Seckl, Jonathan R; Krugers, Harmen J; Joëls, Marian

    2015-01-01

    Early-life stress (ELS) is a risk factor for the development of psychopathology, particularly in women. Human studies have shown that certain haplotypes of NR3C2, encoding the mineralocorticoid receptor (MR), that result in gain of function, may protect against the consequences of stress exposure, including childhood trauma. Here, we tested the hypothesis that forebrain-specific overexpression of MR in female mice would ameliorate the effects of ELS on anxiety and memory in adulthood. We found that ELS increased anxiety, did not alter spatial discrimination and reduced contextual fear memory in adult female mice. Transgenic overexpression of MR did not alter anxiety but affected spatial memory performance and enhanced contextual fear memory formation. The effects of ELS on anxiety and contextual fear were not affected by transgenic overexpression of MR. Thus, MR overexpression in the forebrain does not represent a major resilience factor to early life adversity in female mice.

  14. Working Memory Deficits, Increased Anxiety-Like Traits, and Seizure Susceptibility in BDNF Overexpressing Mice

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    Papaleo, Francesco; Silverman, Jill L.; Aney, Jordan; Tian, Qingjun; Barkan, Charlotte L.; Chadman, Kathryn K.; Crawley, Jacqueline N.

    2011-01-01

    BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher…

  15. Absence of cardiac lipid accumulation in transgenic mice with heart-specific HSL overexpression.

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    Suzuki, J.; Shen, W.J.; Nelson, B.D.; Patel, S.; Veerkamp, J.H.; Selwood, S.P.; Murphy, G.M.; Reaven, E.; Kraemer, F.B.

    2001-01-01

    Hormone-sensitive lipase (HSL) hydrolyzes triglyceride (TG) in adipose tissue. HSL is also expressed in heart. To explore the actions of cardiac HSL, heart-specific, tetracycline (Tc)-controlled HSL-overexpressing mice were generated. Tc-responsive element-HSL transgenic (Tg) mice were generated and

  16. Absence of Hyperplasia in Gasp-1 Overexpressing Mice is Dependent on Myostatin Up-Regulation

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    Caroline Brun

    2014-09-01

    Full Text Available Background/Aims: Overexpression of Gasp-1, an inhibitor of myostatin, leads to a hypermuscular phenotype due to hypertrophy rather than hyperplasia in mice. However to date, the cellular and molecular mechanisms underlying this phenotype are not investigated. Methods: Skeletal muscles of overexpressing Gasp-1 mice, called Tg(Gasp-1 mice, were analyzed by histological methods. Satellite cell-derived myoblasts from these mice were used to investigate the molecular mechanisms. Results: We demonstrated that hypertrophy in Tg(Gasp-1 mice was related to a myonuclear accretion during the first 3 postnatal weeks and an activation of the pro-hypertrophic Akt/mTORC/p70S6K signaling. In accordance with these results, we showed that overexpressing Gasp-1 primary myoblasts proliferated faster and myonuclei average per myotube was increased during differentiation. Molecular analysis revealed that Gasp-1 overexpression resulted in increased myostatin expression related to its auto-regulation. Despite its inhibition, myostatin led to Pax7 deregulation through its non-canonical Erk1/2 signaling pathway. Consistent with this, inhibition of Erk1/2 signaling pathway as well as neutralization of secreted myostatin rescue the Pax7 expression in overexpressing Gasp-1 myoblasts. Conclusion: Our study shows that myostatin is able to act independently of its canonical pathway to regulate the Pax7 expression. Altogether, our results indicate that myostatin could regulate muscle development despite its protein inhibition.

  17. Hepatic NPC1L1 overexpression ameliorates glucose metabolism in diabetic mice via suppression of gluconeogenesis.

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    Kurano, Makoto; Hara, Masumi; Satoh, Hiroaki; Tsukamoto, Kazuhisa

    2015-05-01

    Inhibition of intestinal NPC1L1 by ezetimibe has been demonstrated to improve glucose metabolism in rodent models; however, the role of hepatic NPC1L1 in glucose metabolism has not been elucidated. In this study, we analyzed the effects of hepatic NPC1L1 on glucose metabolism. We overexpressed NPC1L1 in the livers of lean wild type mice, diet-induced obesity mice and db/db mice with adenoviral gene transfer. We found that in all three mouse models, hepatic NPC1L1 overexpression lowered fasting blood glucose levels as well as blood glucose levels on ad libitum; in db/db mice, hepatic NPC1L1 overexpression improved blood glucose levels to almost the same as those found in lean wild type mice. A pyruvate tolerance test revealed that gluconeogenesis was suppressed by hepatic NPC1L1 overexpression. Further analyses revealed that hepatic NPC1L1 overexpression decreased the expression of FoxO1, resulting in the reduced expression of G6Pase and PEPCK, key enzymes in gluconeogenesis. These results indicate that hepatic NPC1L1 might have distinct properties of suppressing gluconeogenesis via inhibition of FoxO1 pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. BDNF Overexpression Exhibited Bilateral Effect on Neural Behavior in SCT Mice Associated with AKT Signal Pathway.

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    Chen, Mei-Rong; Dai, Ping; Wang, Shu-Fen; Song, Shu-Hua; Wang, Hang-Ping; Zhao, Ya; Wang, Ting-Hua; Liu, Jia

    2016-10-01

    Spinal cord injury (SCI), a severe health problem in worldwide, was commonly associated with functional disability and reduced quality of life. As the expression of brain-derived neurotrophic factor (BDNF) was substantial event in injured spinal cord, we hypothesized whether BDNF-overexpression could be in favor of the recovery of both sensory function and hindlimb function after SCI. By using BDNF-overexpression transgene mice [CMV-BDNF 26 (CB26) mice] we assessed the role of BDNF on the recovery of neurological behavior in spinal cord transection (SCT) model. BMS score and tail-flick test was performed to evaluate locomotor function and sensory function, respectively. Immunohistochemistry was employed to detect the location and the expression of BDNF, NeuN, 5-HT, GAP-43, GFAP as well as CGRP, and the level of p-AKT and AKT were examined through western blot analysis. BDNF overexpressing resulted in significant locomotor functional recovery from 21 to 28 days after SCT, compared with wild type (WT)+SCT group. Meanwhile, the NeuN, 5-HT and GAP-43 positive cells were markedly increased in ventral horn in BDNF overexpression animals, compared with WT mice with SCT. Moreover, the crucial molecular signal, p-AKT/AKT has been largely up-regulated, which is consistent with the improvement of locomotor function. However, in this study, thermal hyperpathia encountered in sham (CB26) group and WT+SCT mice and further aggravated in CB26 mice after SCT. Also, following SCT, the significant augment of positive-GFAP astrocytes and CGRP fibers were found in WT+SCT mice, and further increase was seen in BDNF over-expression transgene mice. BDNF-overexpression may not only facilitate the recovery of locomotor function via AKT pathway, but also contributed simultaneously to thermal hyperalgesia after SCT.

  19. Astroglial c-Myc overexpression predisposes mice to primary malignant gliomas

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    Jensen, Niels A; Pedersen, Karen M; Lihme, Frederikke

    2003-01-01

    of the transgenic mice harbored, in addition to brain tumors, vestigial cerebellums in which granule cell migration and radial Bergman glial cell differentiation were disturbed. These observations argue for a window of vulnerability during astrocyte development where c-Myc overexpression is sufficient to trigger...... the neoplastic process, presumably by inducing the sustained growth of early astroglial cells. This is in contrast to most other transgenic studies in which c-Myc overexpression requires co-operating transgenes for rapid tumor induction....

  20. Human paraoxonase 1 overexpression in mice stimulates HDL cholesterol efflux and reverse cholesterol transport

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    Ikhlef, Souade; Berrougui, Hicham; Kamtchueng Simo, Olivier; Zerif, Echarki

    2017-01-01

    This study was aimed to investigate the effect of human PON1 overexpression in mice on cholesterol efflux and reverse cholesterol transport. PON1 overexpression in PON1-Tg mice induced a significant 3-fold (pparaoxonase activity and a significant ~30% (p<0.0001) increase in the capacity of HDL to mediate cholesterol efflux from J774 macrophages compared to wild-type mice. It also caused a significant 4-fold increase (p<0.0001) in the capacity of macrophages to transfer cholesterol to apoA-1, a significant 2-fold (p<0.0003) increase in ABCA1 mRNA and protein expression, and a significant increase in the expression of PPARγ (p<0.0003 and p<0.04, respectively) and LXRα (p<0.0001 and p<0.01, respectively) mRNA and protein compared to macrophages from wild-type mice. Moreover, transfection of J774 macrophages with human PON1 also increased ABCA1, PPARγ and LXRα protein expression and stimulates macrophages cholesterol efflux to apo A1. In vivo measurements showed that the overexpression of PON1 significantly increases the fecal elimination of macrophage-derived cholesterol in PON1-Tg mice. Overall, our results suggested that the overexpression of PON1 in mice may contribute to the regulation of the cholesterol homeostasis by improving the capacity of HDL to mediate cholesterol efflux and by stimulating reverse cholesterol transport. PMID:28278274

  1. Alterations in Adiposity and Glucose Homeostasis in Adult Gasp-1 Overexpressing Mice

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    Luce Périè

    2017-12-01

    Full Text Available Background/Aims: Myostatin is known as a powerful negative regulator of muscle growth playing a key role in skeletal muscle homeostasis. Recent studies revealed that myostatin-deficient mice lead to an increase of insulin sensitivity, a decrease of adiposity and a resistance to obesity, showing that myostatin can also impact on metabolism. Thus, myostatin appeared as a potential therapeutic target to treat insulin resistance. Methods: We generated transgenic mice overexpressing Gasp-1, a myostatin inhibitor. Results: Surprisingly, we found that these mice gained weight with age due to an increase in fat mass associated with ectopic fat accumulation. In addition, these mice developed an adipocyte hypertrophy, hyperglycemia, hyperinsulinemia, muscle and hepatic insulin resistance. Understanding the molecular networks controlling this insulin resistance responsiveness in overexpressing Gasp-1 mice is essential. Molecular analyses revealed a deregulation of adipokines and muscle cytokines expression, but also an increase in plasma myostatin levels. The increase in myostatin bioactivity by a positive feedback mechanism in the Tg(Gasp-1 transgenic mice could lead to this combination of phenotypes. Conclusion: Altogether, these data suggested that overexpressing Gasp-1 mice develop most of the symptoms associated with metabolic syndrome and could be a relevant model for the study of obesity or type 2 diabetes.

  2. Hepatocellular alterations and dysregulation of oncogenic pathways in the liver of transgenic mice overexpressing growth hormone

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    Miquet, Johanna G.; Freund, Thomas; Martinez, Carolina S.; González, Lorena; Díaz, María E.; Micucci, Giannina P.; Zotta, Elsa; Boparai, Ravneet K.; Bartke, Andrzej; Turyn, Daniel; Sotelo, Ana I.

    2013-01-01

    Growth hormone (GH) overexpression throughout life in transgenic mice is associated with the development of liver tumors at old ages. The preneoplastic pathology observed in the liver of young adult GH-overexpressing mice is similar to that present in humans at high risk of hepatic cancer. To elucidate the molecular pathogenesis underlying the pro-oncogenic liver pathology induced by prolonged exposure to elevated GH levels, the activation and expression of several components of signal transduction pathways that have been implicated in hepatocellular carcinogenesis were evaluated in the liver of young adult GH-transgenic mice. In addition, males and females were analyzed in parallel in order to evaluate sexual dimorphism. Transgenic mice from both sexes exhibited hepatocyte hypertrophy with enlarged nuclear size and exacerbated hepatocellular proliferation, which were higher in males. Dysregulation of several oncogenic pathways was observed in the liver of GH-overexpressing transgenic mice. Many signaling mediators and effectors were upregulated in transgenic mice compared with normal controls, including Akt2, NFκB, GSK3β, β-catenin, cyclin D1, cyclin E, c-myc, c-jun and c-fos. The molecular alterations described did not exhibit sexual dimorphism in transgenic mice except for higher gene expression and nuclear localization of cyclin D1 in males. We conclude that prolonged exposure to GH induces in the liver alterations in signaling pathways involved in cell growth, proliferation and survival that resemble those found in many human tumors. PMID:23428905

  3. Estrogen receptor alpha deletion enhances the metastatic phenotype of Ron overexpressing mammary tumors in mice

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    Marshall Aaron M

    2012-01-01

    Full Text Available Abstract Background The receptor tyrosine kinase family includes many transmembrane proteins with diverse physiological and pathophysiological functions. The involvement of tyrosine kinase signaling in promoting a more aggressive tumor phenotype within the context of chemotherapeutic evasion is gaining recognition. The Ron receptor is a tyrosine kinase receptor that has been implicated in the progression of breast cancer and evasion of tamoxifen therapy. Results Here, we report that Ron expression is correlated with in situ, estrogen receptor alpha (ERα-positive tumors, and is higher in breast tumors following neoadjuvant tamoxifen therapy. We also demonstrate that the majority of mammary tumors isolated from transgenic mice with mammary specific-Ron overexpression (MMTV-Ron mice, exhibit appreciable ER expression. Moreover, genetic-ablation of ERα, in the context of Ron overexpression, leads to delayed mammary tumor initiation and growth, but also results in an increased metastasis. Conclusions Ron receptor overexpression is associated with ERα-positive human and murine breast tumors. In addition, loss of ERα on a Ron overexpressing background in mice leads to the development of breast tumors which grow slower but which exhibit more metastasis and suggests that targeting of ERα, as in the case of tamoxifen therapy, may reduce the growth of Ron overexpressing breast cancers but may cause these tumors to be more metastatic.

  4. Myocardial overexpression of adenine nucleotide translocase 1 ameliorates diabetic cardiomyopathy in mice.

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    Wang, Yong; Ebermann, Linda; Sterner-Kock, Anja; Wika, Sylwia; Schultheiss, Heinz-Peter; Dörner, Andrea; Walther, Thomas

    2009-02-01

    Mitochondrial dysfunction is implicated in the pathogenesis of diabetic cardiomyopathy, a common complication of diabetes. Adenosine nucleotide translocase (ANT) translocates ADP/ATP across the inner mitochondrial membrane. Our study aimed to test the hypothesis that overexpression of ANT1 in cardiomyocytes has cardioprotective effects in diabetic cardiomyopathy induced by streptozotocin (STZ). Mice specifically overexpressing murine ANT1 in the heart were generated using alpha-myosin heavy chain promoter. Expression of ANT1 mRNA and protein in hearts was characterized by real-time polymerase chain reaction and Western blot analysis. Five- to 6-month-old male transgenic mice and their age-matched wild-type littermates were subjected to type 1 diabetes induced by STZ. Six weeks later, haemodynamic measurement was performed to assess cardiac function. Ventricular mRNA expression of atrial natriuretic peptide, a molecular marker of heart failure, was characterized by RNase-protection assay. Both ANT1 mRNA and ANT1 protein were specifically overexpressed in the heart of transgenic mice. Heart weight was decreased and cardiac function was dramatically impaired in wild-type mice 6 weeks after induction of diabetes, but ANT1 overexpression prevented these significant changes. The mRNA expression level of atrial natriuretic peptide confirmed the haemodynamic findings, being upregulated in wild-type mice receiving STZ, but showing no statistical differences in ANT1 transgenic mice. Cardiomyocyte-restricted overexpression of ANT1 prevents the development of diabetic cardiomyopathy; therefore, accelerated ADP/ATP exchange could be a new promising target to treat diabetic cardiomyopathy.

  5. Overexpression of Indian hedgehog partially rescues short stature homeobox 2-overexpression-associated congenital dysplasia of the temporomandibular joint in mice.

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    Li, Xihai; Liang, Wenna; Ye, Hongzhi; Weng, Xiaping; Liu, Fayuan; Lin, Pingdong; Liu, Xianxiang

    2015-09-01

    The role of short stature homeobox 2 (shox2) in the development and homeostasis of the temporomandibular joint (TMJ) has been well documented. Shox2 is known to be expressed in the progenitor cells and perichondrium of the developing condyle. A previous study by our group reported that overexpression of shox2 leads to congenital dysplasia of the TMJ via downregulation of the Indian hedgehog (Ihh) signaling pathway, which is essential for embryonic disc primordium formation and mandibular condylar growth. To determine whether overexpression of Ihh may rescue the overexpression of shox2 leading to congenital dysplasia of the TMJ, a mouse model in which Ihh and shox2 were overexpressed (Wnt1-Cre; pMes-stop shox2; pMes-stop Ihh mice) was utilized to assess the consequences of this overexpression on TMJ development during post-natal life. The results showed that the developmental process and expression levels of runt-related transcription factor 2 and sex determining region Y-box 9 in the TMJ of the Wnt1-Cre; pMes-stop shox2; pMes-stop Ihh mice were similar to those in wild‑type mice. Overexpression of Ihh rescued shox2 overexpression-associated reduction of extracellular matrix components. However, overexpression of Ihh did not inhibit the shox2 overexpression-associated increase of matrix metalloproteinases (MMPs) MMP9, MMP13 and apoptosis in the TMJ. These combinatory cellular and molecular defects appeared to account for the observed congenital dysplasia of TMJ, suggesting that overexpression of Ihh partially rescued shox2 overexpression‑associated congenital dysplasia of the TMJ in mice.

  6. Small heterodimer partner overexpression partially protects against liver tumor development in farnesoid X receptor knockout mice

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    Li, Guodong; Kong, Bo; Zhu, Yan; Zhan, Le; Williams, Jessica A.; Tawfik, Ossama; Kassel, Karen M.; Luyendyk, James P.; Wang, Li; Guo, Grace L.

    2013-01-01

    Farnesoid X receptor (FXR, Nr1h4) and small heterodimer partner (SHP, Nr0b2) are nuclear receptors that are critical to liver homeostasis. Induction of SHP serves as a major mechanism of FXR in suppressing gene expression. Both FXR −/− and SHP −/− mice develop spontaneous hepatocellular carcinoma (HCC). SHP is one of the most strongly induced genes by FXR in the liver and is a tumor suppressor, therefore, we hypothesized that deficiency of SHP contributes to HCC development in the livers of FXR −/− mice and therefore, increased SHP expression in FXR −/− mice reduces liver tumorigenesis. To test this hypothesis, we generated FXR −/− mice with overexpression of SHP in hepatocytes (FXR −/− /SHP Tg ) and determined the contribution of SHP in HCC development in FXR −/− mice. Hepatocyte-specific SHP overexpression did not affect liver tumor incidence or size in FXR −/− mice. However, SHP overexpression led to a lower grade of dysplasia, reduced indicator cell proliferation and increased apoptosis. All tumor-bearing mice had increased serum bile acid levels and IL-6 levels, which was associated with activation of hepatic STAT3. In conclusion, SHP partially protects FXR −/− mice from HCC formation by reducing tumor malignancy. However, disrupted bile acid homeostasis by FXR deficiency leads to inflammation and injury, which ultimately results in uncontrolled cell proliferation and tumorigenesis in the liver. - Highlights: • SHP does not prevent HCC incidence nor size in FXR KO mice but reduces malignancy. • Increased SHP promotes apoptosis. • Bile acids and inflammation maybe critical for HCC formation with FXR deficiency

  7. Transgenic Mice Overexpressing Vitamin D Receptor (VDR) Show Anti-Inflammatory Effects in Lung Tissues.

    Science.gov (United States)

    Ishii, Masaki; Yamaguchi, Yasuhiro; Isumi, Kyoko; Ogawa, Sumito; Akishita, Masahiro

    2017-12-01

    Vitamin D insufficiency is increasingly recognized as a prevalent problem worldwide, especially in patients with a chronic lung disease. Chronic obstructive pulmonary disease (COPD) is a type of chronic inflammatory lung disease. Previous clinical studies have shown that COPD leads to low vitamin D levels, which further increase the severity of COPD. Vitamin D homeostasis represents one of the most important factors that potentially determine the severity of COPD. Nonetheless, the mechanisms underlying the anti-inflammatory effects of vitamin D receptor (VDR) in lung tissues are still unclear. To investigate the anti-inflammatory effects of VDR, we generated transgenic mice that show lung-specific VDR overexpression under the control of the surfactant protein C promoter (TG mice). The TG mice were used to study the expression patterns of proinflammatory cytokines using real-time polymerase chain reaction and immunohistochemistry. The TG mice had lower levels of T helper 1 (Th1)-related cytokines than wild-type (WT) mice did. No significant differences in the expression of Th2 cytokines were observed between TG and WT mice. This study is the first to achieve lung-specific overexpression of VDR in TG mice: an interesting animal model useful for studying the relation between airway cell inflammation and vitamin D signaling. VDR expression is an important factor that influences anti-inflammatory responses in lung tissues. Our results show the crucial role of VDR in anti-inflammatory effects in lungs; these data are potentially useful for the treatment or prevention of COPD.

  8. Endothelin-1 Overexpression Improves Renal Function in eNOS Knockout Mice

    Directory of Open Access Journals (Sweden)

    Oleg Tsuprykov

    2015-10-01

    Full Text Available Background/Aims: To investigate the renal phenotype under conditions of an activated renal ET-1 system in the status of nitric oxide deficiency, we compared kidney function and morphology in wild-type, ET-1 transgenic (ET+/+, endothelial nitric oxide synthase knockout (eNOS-/- and ET+/+eNOS-/- mice. Methods: We assessed blood pressure, parameters of renal morphology, plasma cystatin C, urinary protein excretion, expression of genes associated with glomerular filtration barrier and tissue remodeling, and plasma metabolites using metabolomics. Results: eNOS-/- and ET+/+eNOS-/- mice developed hypertension. Osteopontin, albumin and protein excretion were increased in eNOS-/- and restored in ET+/+eNOS-/- animals. All genetically modified mice developed renal interstitial fibrosis and glomerulosclerosis. Genes involved in tissue remodeling (serpine1, TIMP1, Col1a1, CCL2 were up-regulated in eNOS-/-, but not in ET+/+eNOS-/- mice. Plasma levels of free carnitine and acylcarnitines, amino acids, diacyl phosphatidylcholines, lysophosphatidylcholines and hexoses were descreased in eNOS-/- and were in the normal range in ET+/+eNOS-/- mice. Conclusion: eNOS-/- mice developed renal dysfunction, which was partially rescued by ET-1 overexpression in eNOS-/- mice. The metabolomics results suggest that ET-1 overexpression on top of eNOS knockout is associated with a functional recovery of mitochondria (rescue effect in β-oxidation of fatty acids and an increase in antioxidative properties (normalization of monounsaturated fatty acids levels.

  9. Effects of mineralocorticoid receptor overexpression on anxiety and memory after early life stress in female mice

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    Sofia eKanatsou

    2016-01-01

    Full Text Available Early-life stress is a risk factor for the development of psychopathology, particularly in women. Human studies have shown that certain haplotypes of NR3C2, encoding the mineralocorticoid receptor (MR, that result in gain of function, may protect against the consequences of stress exposure, including childhood trauma. Here, we tested the hypothesis that forebrain-specific overexpression of MR in female mice would ameliorate the effects of early-life stress on anxiety and memory in adulthood. We found that early-life stress increased anxiety, did not alter spatial discrimination and reduced contextual fear memory in adult female mice. Transgenic overexpression of MR did not alter anxiety but affected spatial memory performance and enhanced contextual fear memory formation. The effects of early life stress on anxiety and contextual fear were not affected by transgenic overexpression of MR. Thus MR overexpression in the forebrain does not represent a major resilience factor to early life adversity in female mice.

  10. Striatal dopamine transmission is subtly modified in human A53Tα-synuclein overexpressing mice.

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    Nicola J Platt

    Full Text Available Mutations in, or elevated dosage of, SNCA, the gene for α-synuclein (α-syn, cause familial Parkinson's disease (PD. Mouse lines overexpressing the mutant human A53Tα-syn may represent a model of early PD. They display progressive motor deficits, abnormal cellular accumulation of α-syn, and deficits in dopamine-dependent corticostriatal plasticity, which, in the absence of overt nigrostriatal degeneration, suggest there are age-related deficits in striatal dopamine (DA signalling. In addition A53Tα-syn overexpression in cultured rodent neurons has been reported to inhibit transmitter release. Therefore here we have characterized for the first time DA release in the striatum of mice overexpressing human A53Tα-syn, and explored whether A53Tα-syn overexpression causes deficits in the release of DA. We used fast-scan cyclic voltammetry to detect DA release at carbon-fibre microelectrodes in acute striatal slices from two different lines of A53Tα-syn-overexpressing mice, at up to 24 months. In A53Tα-syn overexpressors, mean DA release evoked by a single stimulus pulse was not different from wild-types, in either dorsal striatum or nucleus accumbens. However the frequency responsiveness of DA release was slightly modified in A53Tα-syn overexpressors, and in particular showed slight deficiency when the confounding effects of striatal ACh acting at presynaptic nicotinic receptors (nAChRs were antagonized. The re-release of DA was unmodified after single-pulse stimuli, but after prolonged stimulation trains, A53Tα-syn overexpressors showed enhanced recovery of DA release at old age, in keeping with elevated striatal DA content. In summary, A53Tα-syn overexpression in mice causes subtle changes in the regulation of DA release in the striatum. While modest, these modifications may indicate or contribute to striatal dysfunction.

  11. Selective endothelial overexpression of arginase II induces endothelial dysfunction and hypertension and enhances atherosclerosis in mice.

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    Boris L Vaisman

    Full Text Available Cardiovascular disorders associated with endothelial dysfunction, such as atherosclerosis, have decreased nitric oxide (NO bioavailability. Arginase in the vasculature can compete with eNOS for L-arginine and has been implicated in atherosclerosis. The aim of this study was to evaluate the effect of endothelial-specific elevation of arginase II expression on endothelial function and the development of atherosclerosis.Transgenic mice on a C57BL/6 background with endothelial-specific overexpression of human arginase II (hArgII gene under the control of the Tie2 promoter were produced. The hArgII mice had elevated tissue arginase activity except in liver and in resident peritoneal macrophages, confirming endothelial specificity of the transgene. Using small-vessel myography, aorta from these mice exhibited endothelial dysfunction when compared to their non-transgenic littermate controls. The blood pressure of the hArgII mice was 17% higher than their littermate controls and, when crossed with apoE -/- mice, hArgII mice had increased aortic atherosclerotic lesions.We conclude that overexpression of arginase II in the endothelium is detrimental to the cardiovascular system.

  12. Phenotypic characterization of transgenic mice overexpressing neuregulin-1.

    Directory of Open Access Journals (Sweden)

    Taisuke Kato

    Full Text Available BACKGROUND: Neuregulin-1 (NRG1 is one of the susceptibility genes for schizophrenia and implicated in the neurotrophic regulation of GABAergic and dopaminergic neurons, myelination, and NMDA receptor function. Postmortem studies often indicate a pathologic association of increased NRG1 expression or signaling with this illness. However, the psychobehavioral implication of NRG1 signaling has mainly been investigated using hypomorphic mutant mice for individual NRG1 splice variants. METHODOLOGY/PRINCIPAL FINDINGS: To assess the behavioral impact of hyper NRG1 signaling, we generated and analyzed two independent mouse transgenic (Tg lines carrying the transgene of green fluorescent protein (GFP-tagged type-1 NRG1 cDNA. The promoter of elongation-factor 1α gene drove ubiquitous expression of GFP-tagged NRG1 in the whole brain. As compared to control littermates, both heterozygous NRG1-Tg lines showed increased locomotor activity, a nonsignificant trend toward decreasing prepulse inhibition, and decreased context-dependent fear learning but exhibited normal levels of tone-dependent learning. In addition, social interaction scores in both Tg lines were reduced in an isolation-induced resident-intruder test. There were also phenotypic increases in a GABAergic marker (parvalbumin as well as in myelination markers (myelin basic protein and 2',3'-cyclic nucleotide 3'-phosphodiesterase in their frontal cortex, indicating the authenticity of NRG1 hyper-signaling, although there were marked decreases in tyrosine hydroxylase levels and dopamine content in the hippocampus. CONCLUSIONS: These findings suggest that aberrant hyper-signals of NRG1 also disrupt various cognitive and behavioral processes. Thus, neuropathological implication of hyper NRG1 signaling in psychiatric diseases should be evaluated with further experimentation.

  13. FHL1 reduces dystrophy in transgenic mice overexpressing FSHD muscular dystrophy region gene 1 (FRG1.

    Directory of Open Access Journals (Sweden)

    Sandra J Feeney

    Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is an autosomal-dominant disease with no effective treatment. The genetic cause of FSHD is complex and the primary pathogenic insult underlying the muscle disease is unknown. Several disease candidate genes have been proposed including DUX4 and FRG1. Expression analysis studies of FSHD report the deregulation of genes which mediate myoblast differentiation and fusion. Transgenic mice overexpressing FRG1 recapitulate the FSHD muscular dystrophy phenotype. Our current study selectively examines how increased expression of FRG1 may contribute to myoblast differentiation defects. We generated stable C2C12 cell lines overexpressing FRG1, which exhibited a myoblast fusion defect upon differentiation. To determine if myoblast fusion defects contribute to the FRG1 mouse dystrophic phenotype, this strain was crossed with skeletal muscle specific FHL1-transgenic mice. We previously reported that FHL1 promotes myoblast fusion in vitro and FHL1-transgenic mice develop skeletal muscle hypertrophy. In the current study, FRG1 mice overexpressing FHL1 showed an improvement in the dystrophic phenotype, including a reduced spinal kyphosis, increased muscle mass and myofiber size, and decreased muscle fibrosis. FHL1 expression in FRG1 mice, did not alter satellite cell number or activation, but enhanced myoblast fusion. Primary myoblasts isolated from FRG1 mice showed a myoblast fusion defect that was rescued by FHL1 expression. Therefore, increased FRG1 expression may contribute to a muscular dystrophy phenotype resembling FSHD by impairing myoblast fusion, a defect that can be rescued by enhanced myoblast fusion via expression of FHL1.

  14. Effect of bcl-2 overexpression in mice on ovotoxicity caused by 4-vinylcyclohexene

    International Nuclear Information System (INIS)

    Flaws, Jodi A.; Marion, Samuel L.; Miller, Kimberly P.; Christian, Patricia J.; Babus, Janice K.; Hoyer, Patricia B.

    2006-01-01

    The occupational chemical 4-vinylcyclohexene (VCH) destroys small preantral ovarian follicles in mice following repeated daily dosing. The cell survival gene bcl-2 is thought to protect against follicular death during embryogenesis because primordial follicle numbers in newborn bcl-2 overexpressing (OE) mice are greater than in wild-type (WT) controls. Thus, this study was designed to determine if overexpression of bcl-2 protects against VCH-induced follicle loss during embryonic development. Pregnant bcl-2 OE or WT mice were dosed (p.o.) daily with VCH (500 mg/kg) or sesame oil (vehicle control) on days 8-18 of pregnancy. Ovaries were collected from moms and female pups on pup postnatal day (PND) 8. Nonpregnant OE and WT females were also treated with VCH (500 mg/kg p.o.) or vehicle and evaluated in the same manner. As previously reported, ovaries from PND8 OE female pups contained 50% more primordial follicles than WT pups (P < 0.05). Unlike WT pups, relative to vehicle controls, in utero exposure to VCH resulted in a reduction in primordial (25% of control), primary (38% of control), and secondary (33% of control) follicles in ovaries of OE pups (P < 0.05). VCH had no significant effect on follicle numbers in OE or WT moms. Conversely, in nonpregnant adults, VCH did not affect WT mice but caused loss of primordial (55% of control), primary (51% of control), and secondary (69% of control) follicles in OE mice (P < 0.05). These results demonstrate that bcl-2 overexpression does not protect against, but instead increases susceptibility to VCH-induced follicle loss in transplacentally exposed or in nonpregnant mice

  15. Compensation of the AKT signaling by ERK signaling in transgenic mice hearts overexpressing TRIM72

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Young-Mi, E-mail: youngmi_ham@hms.harvard.edu [College of Life Science and Biotechnology, Korea University, Seoul (Korea, Republic of); Department of Cell Biology, Harvard Medical School, Boston, MA 02115 (United States); Mahoney, Sarah Jane [Department of Cell Biology, Harvard Medical School, Boston, MA 02115 (United States)

    2013-06-10

    The AKT and ERK signaling pathways are known to be involved in cell hypertrophy, proliferation, survival and differentiation. Although there is evidence for crosstalk between these two signaling pathways in cellulo, there is less evidence for cross talk in vivo. Here, we show that crosstalk between AKT and ERK signaling in the hearts of TRIM72-overexpressing transgenic mice (TRIM72-Tg) with alpha-MHC promoter regulates and maintains their heart size. TRIM72, a heart- and skeletal muscle-specific protein, downregulates AKT-mTOR signaling via IRS-1 degradation and reduces the size of rat cardiomyocytes and the size of postnatal TRIM72-Tg hearts. TRIM72 expression was upregulated by hypertrophic inducers in cardiomyocytes, while IRS-1 was downregulated by IGF-1. TRIM72 specifically regulated IGF-1-dependent AKT-mTOR signaling, resulting in a reduction of the size of cardiomyocytes. Postnatal TRIM72-Tg hearts were smaller than control-treated hearts with inhibition of AKT-mTOR signaling. However, adult TRIM72-Tg hearts were larger than of control despite the suppression of AKT-mTOR signaling. Activation of ERK, PKC-α, and JNK were observed to be elevated in adult TRIM72-Tg, and these signals were mediated by ET-1 via the ET receptors A and B. Altogether, these results suggest that AKT signaling regulates cardiac hypertrophy in physiological conditions, and ERK signaling compensates for the absence of AKT signaling during TRIM72 overexpression, leading to pathological hypertrophy. -- Highlights: • TRIM72 inhibits AKT signaling through ubiquitination of IRS-1 in cardiac cells. • TRIM72 regulates the size of cardiac cells. • TRIM72 regulates size of postnatal TRIM72-overexpressing transgenic mice hearts. • Adult TRIM72-overexpressing transgenic mice hearts showed cardiac dysfunction. • Adult TRIM72 transgenic mice hearts showed higher expression of endothelin receptors.

  16. Compensation of the AKT signaling by ERK signaling in transgenic mice hearts overexpressing TRIM72

    International Nuclear Information System (INIS)

    Ham, Young-Mi; Mahoney, Sarah Jane

    2013-01-01

    The AKT and ERK signaling pathways are known to be involved in cell hypertrophy, proliferation, survival and differentiation. Although there is evidence for crosstalk between these two signaling pathways in cellulo, there is less evidence for cross talk in vivo. Here, we show that crosstalk between AKT and ERK signaling in the hearts of TRIM72-overexpressing transgenic mice (TRIM72-Tg) with alpha-MHC promoter regulates and maintains their heart size. TRIM72, a heart- and skeletal muscle-specific protein, downregulates AKT-mTOR signaling via IRS-1 degradation and reduces the size of rat cardiomyocytes and the size of postnatal TRIM72-Tg hearts. TRIM72 expression was upregulated by hypertrophic inducers in cardiomyocytes, while IRS-1 was downregulated by IGF-1. TRIM72 specifically regulated IGF-1-dependent AKT-mTOR signaling, resulting in a reduction of the size of cardiomyocytes. Postnatal TRIM72-Tg hearts were smaller than control-treated hearts with inhibition of AKT-mTOR signaling. However, adult TRIM72-Tg hearts were larger than of control despite the suppression of AKT-mTOR signaling. Activation of ERK, PKC-α, and JNK were observed to be elevated in adult TRIM72-Tg, and these signals were mediated by ET-1 via the ET receptors A and B. Altogether, these results suggest that AKT signaling regulates cardiac hypertrophy in physiological conditions, and ERK signaling compensates for the absence of AKT signaling during TRIM72 overexpression, leading to pathological hypertrophy. -- Highlights: • TRIM72 inhibits AKT signaling through ubiquitination of IRS-1 in cardiac cells. • TRIM72 regulates the size of cardiac cells. • TRIM72 regulates size of postnatal TRIM72-overexpressing transgenic mice hearts. • Adult TRIM72-overexpressing transgenic mice hearts showed cardiac dysfunction. • Adult TRIM72 transgenic mice hearts showed higher expression of endothelin receptors

  17. Nras Overexpression Results in Granulocytosis, T-Cell Expansion and Early Lethality in Mice

    DEFF Research Database (Denmark)

    Lassen, Louise Berkhoudt; Gonzalez, Borja Ballarin; Schmitz, Alexander

    2012-01-01

    NRAS is a proto-oncogene involved in numerous myeloid malignancies. Here, we report on a mouse line bearing a single retroviral long terminal repeat inserted into Nras. This genetic modification resulted in an increased level of wild type Nras mRNA giving the possibility of studying the function ...... the increment in immature myeloid cells detected in these mice. The short latency period indicates that Nras overexpression alone is sufficient to cause dose-dependent granulocytosis and T-cell expansion....

  18. Primary hyperparathyroidism caused by parathyroid-targeted overexpression of cyclin D1 in transgenic mice

    OpenAIRE

    Imanishi, Yasuo; Hosokawa, Yoshitaka; Yoshimoto, Katsuhiko; Schipani, Ernestina; Mallya, Sanjay; Papanikolaou, Alexandros; Kifor, Olga; Tokura, Takehiko; Sablosky, Marilyn; Ledgard, Felicia; Gronowicz, Gloria; Wang, Timothy C.; Schmidt, Emmett V.; Hall, Charles; Brown, Edward M.

    2001-01-01

    The relationship between abnormal cell proliferation and aberrant control of hormonal secretion is a fundamental and poorly understood issue in endocrine cell neoplasia. Transgenic mice with parathyroid-targeted overexpression of the cyclin D1 oncogene, modeling a gene rearrangement found in human tumors, were created to determine whether a primary defect in this cell-cycle regulator can cause an abnormal relationship between serum calcium and parathyroid hormone response, as is typical of hu...

  19. Transgenic overexpression of ADAM12 suppresses muscle regeneration and aggravates dystrophy in aged mdx mice

    DEFF Research Database (Denmark)

    Jørgensen, Louise Helskov; Jensen, Charlotte Harken; Wewer, Ulla M

    2007-01-01

    Muscular dystrophies are characterized by insufficient restoration and gradual replacement of the skeletal muscle by fat and connective tissue. ADAM12 has previously been shown to alleviate the pathology of young dystrophin-deficient mdx mice, a model for Duchenne muscular dystrophy. The observed...... that ADAM12 could be a candidate for nonreplacement gene therapy of Duchenne muscular dystrophy. We therefore evaluated the long-term effect of ADAM12 overexpression in muscle. Surprisingly, we observed loss of skeletal muscle and accelerated fibrosis and adipogenesis in 1-year-old mdx mice transgenically...... regeneration as a possible factor in development of muscular dystrophy....

  20. Morphogenetic roles of perlecan in the tooth enamel organ: an analysis of overexpression using transgenic mice.

    Science.gov (United States)

    Ida-Yonemochi, Hiroko; Satokata, Ichiro; Ohshima, Hayato; Sato, Toshiya; Yokoyama, Minesuke; Yamada, Yoshihiko; Saku, Takashi

    2011-09-01

    Perlecan, a heparan sulfate proteoglycan, is enriched in the intercellular space of the enamel organ. To understand the role of perlecan in tooth morphogenesis, we used a keratin 5 promoter to generate transgenic (Tg) mice that over-express perlecan in epithelial cells, and examined their tooth germs at tissue and cellular levels. Immunohistochemistry showed that perlecan was more strongly expressed in the enamel organ cells of Tg mice than in wild-type mice. Histopathology showed wider intercellular spaces in the stellate reticulum of the Tg molars and loss of cellular polarity in the enamel organ, especially in its cervical region. Hertwig's epithelial root sheath (HERS) cells in Tg mice were irregularly aligned due to excessive deposits of perlecan along the inner, as well as on the outer sides of the HERS. Tg molars had dull-ended crowns and outward-curved tooth roots and their enamel was poorly crystallized, resulting in pronounced attrition of molar cusp areas. In Tg mice, expression of integrin β1 mRNA was remarkably higher at E18, while expression of bFGF, TGF-β1, DSPP and Shh was more elevated at P1. The overexpression of perlecan in the enamel organ resulted in irregular morphology of teeth, suggesting that the expression of perlecan regulates growth factor signaling in a stage-dependent manner during each step of the interaction between ameloblast-lineage cells and mesenchymal cells. Copyright © 2011 International Society of Matrix Biology. All rights reserved.

  1. Calpastatin overexpression impairs postinfarct scar healing in mice by compromising reparative immune cell recruitment and activation.

    Science.gov (United States)

    Wan, Feng; Letavernier, Emmanuel; Le Saux, Claude Jourdan; Houssaini, Amal; Abid, Shariq; Czibik, Gabor; Sawaki, Daigo; Marcos, Elisabeth; Dubois-Rande, Jean-Luc; Baud, Laurent; Adnot, Serge; Derumeaux, Geneviève; Gellen, Barnabas

    2015-12-01

    The activation of the calpain system is involved in the repair process following myocardial infarction (MI). However, the impact of the inhibition of calpain by calpastatin, its natural inhibitor, on scar healing and left ventricular (LV) remodeling is elusive. Male mice ubiquitously overexpressing calpastatin (TG) and wild-type (WT) controls were subjected to an anterior coronary artery ligation. Mortality at 6 wk was higher in TG mice (24% in WT vs. 44% in TG, P < 0.05) driven by a significantly higher incidence of cardiac rupture during the first week post-MI, despite comparable infarct size and LV dysfunction and dilatation. Calpain activation post-MI was blunted in TG myocardium. In TG mice, inflammatory cell infiltration and activation were reduced in the infarct zone (IZ), particularly affecting M2 macrophages and CD4(+) T cells, which are crucial for scar healing. To elucidate the role of calpastatin overexpression in macrophages, we stimulated peritoneal macrophages obtained from TG and WT mice in vitro with IL-4, yielding an abrogated M2 polarization in TG but not in WT cells. Lymphopenic Rag1(-/-) mice receiving TG splenocytes before MI demonstrated decreased T-cell recruitment and M2 macrophage activation in the IZ day 5 after MI compared with those receiving WT splenocytes. Calpastatin overexpression prevented the activation of the calpain system after MI. It also impaired scar healing, promoted LV rupture, and increased mortality. Defective scar formation was associated with blunted CD4(+) T-cell and M2-macrophage recruitment. Copyright © 2015 the American Physiological Society.

  2. Working memory deficits, increased anxiety-like traits, and seizure susceptibility in BDNF overexpressing mice

    Science.gov (United States)

    Papaleo, Francesco; Silverman, Jill L.; Aney, Jordan; Tian, Qingjun; Barkan, Charlotte L.; Chadman, Kathryn K.; Crawley, Jacqueline N.

    2011-01-01

    BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher anxiety-like scores, high self-grooming, impaired prepulse inhibition, and higher susceptibility to seizures when placed in a new empty cage, as compared with wild-type (WT) littermate controls. Control measures of general health, locomotor activity, motor coordination, depression-related behaviors, and sociability did not differ between genotypes. The present findings, indicating detrimental effects of life-long increased BDNF in mice, may inform human studies evaluating the role of BDNF functional genetic variations on cognitive abilities and vulnerability to psychiatric disorders. PMID:21791566

  3. Characterisation of the nociceptive phenotype of suppressible galanin overexpressing transgenic mice

    Directory of Open Access Journals (Sweden)

    Wynick David

    2010-10-01

    Full Text Available Abstract The neuropeptide galanin is widely expressed in both the central and peripheral nervous systems and is involved in many diverse biological functions. There is a substantial data set that demonstrates galanin is upregulated after injury in the DRG, spinal cord and in many brain regions where it plays a predominantly antinociceptive role in addition to being neuroprotective and pro-regenerative. To further characterise the role of galanin following nerve injury, a novel transgenic line was created using the binary transgenic tet-off system, to overexpress galanin in galaninergic tissue in a suppressible manner. The double transgenic mice express significantly more galanin in the DRG one week after sciatic nerve section (axotomy compared to WT mice and this overexpression is suppressible upon administration of doxycycline. Phenotypic analysis revealed markedly attenuated allodynia when galanin is overexpressed and an increase in allodynia following galanin suppression. This novel transgenic line demonstrates that whether galanin expression is increased at the time of nerve injury or only after allodynia is established, the neuropeptide is able to reduce neuropathic pain behaviour. These new findings imply that administration of a galanin agonist to patients with established allodynia would be an effective treatment for neuropathic pain.

  4. Tubular overexpression of Gremlin in transgenic mice aggravates renal damage in diabetic nephropathy.

    Science.gov (United States)

    Marchant, Vanessa; Droguett, Alejandra; Valderrama, Graciela; Burgos, M Eugenia; Carpio, Daniel; Kerr, Bredford; Ruiz-Ortega, Marta; Egido, Jesús; Mezzano, Sergio

    2015-09-15

    Diabetic nephropathy (DN) is currently a leading cause of end-stage renal failure worldwide. Gremlin was identified as a gene differentially expressed in mesangial cells exposed to high glucose and in experimental diabetic kidneys. We have described that Gremlin is highly expressed in biopsies from patients with diabetic nephropathy, predominantly in areas of tubulointerstitial fibrosis. In streptozotocin (STZ)-induced experimental diabetes, Gremlin deletion using Grem1 heterozygous knockout mice or by gene silencing, ameliorates renal damage. To study the in vivo role of Gremlin in renal damage, we developed a diabetic model induced by STZ in transgenic (TG) mice expressing human Gremlin in proximal tubular epithelial cells. The albuminuria/creatinuria ratio, determined at week 20 after treatment, was significantly increased in diabetic mice but with no significant differences between transgenic (TG/STZ) and wild-type mice (WT/STZ). To assess the level of renal damage, kidney tissue was analyzed by light microscopy (periodic acid-Schiff and Masson staining), electron microscopy, and quantitative PCR. TG/STZ mice had significantly greater thickening of the glomerular basement membrane, increased mesangial matrix, and podocytopenia vs. WT/STZ. At the tubulointerstitial level, TG/STZ showed increased cell infiltration and mild interstitial fibrosis. In addition, we observed a decreased expression of podocin and overexpression of monocyte chemoattractant protein-1 and fibrotic-related markers, including transforming growth factor-β1, Col1a1, and α-smooth muscle actin. Together, these results show that TG mice overexpressing Gremlin in renal tubules develop greater glomerular and tubulointerstitial injury in response to diabetic-mediated damage and support the involvement of Gremlin in diabetic nephropathy. Copyright © 2015 the American Physiological Society.

  5. Oncolytic adenovirus targeting cyclin E overexpression repressed tumor growth in syngeneic immunocompetent mice

    International Nuclear Information System (INIS)

    Cheng, Pei-Hsin; Rao, Xiao-Mei; Wechman, Stephen L.; Li, Xiao-Feng; McMasters, Kelly M.; Zhou, Heshan Sam

    2015-01-01

    Clinical trials have indicated that preclinical results obtained with human tumor xenografts in mouse models may overstate the potential of adenovirus (Ad)-mediated oncolytic therapies. We have previously demonstrated that the replication of human Ads depends on cyclin E dysregulation or overexpression in cancer cells. ED-1 cell derived from mouse lung adenocarcinomas triggered by transgenic overexpression of human cyclin E may be applied to investigate the antitumor efficacy of oncolytic Ads. Ad-cycE was used to target cyclin E overexpression in ED-1 cells and repress tumor growth in a syngeneic mouse model for investigation of oncolytic virotherapies. Murine ED-1 cells were permissive for human Ad replication and Ad-cycE repressed ED-1 tumor growth in immunocompetent FVB mice. ED-1 cells destroyed by oncolytic Ads in tumors were encircled in capsule-like structures, while cells outside the capsules were not infected and survived the treatment. Ad-cycE can target cyclin E overexpression in cancer cells and repress tumor growth in syngeneic mouse models. The capsule structures formed after Ad intratumoral injection may prevent viral particles from spreading to the entire tumor. The online version of this article (doi:10.1186/s12885-015-1731-x) contains supplementary material, which is available to authorized users

  6. Neuronal erythropoietin overexpression protects mice against age-related hearing loss (presbycusis).

    Science.gov (United States)

    Monge Naldi, Arianne; Belfrage, Celina; Jain, Neha; Wei, Eric T; Canto Martorell, Belén; Gassmann, Max; Vogel, Johannes

    2015-12-01

    So far, typical causes of presbycusis such as degeneration of hair cells and/or primary auditory (spiral ganglion) neurons cannot be treated. Because erythropoietin's (Epo) neuroprotective potential has been shown previously, we determined hearing thresholds of juvenile and aged mice overexpressing Epo in neuronal tissues. Behavioral audiometry revealed in contrast to 5 months of age, that 11-month-old Epo-transgenic mice had up to 35 dB lower hearing thresholds between 1.4 and 32 kHz, and at the highest frequencies (50-80 kHz), thresholds could be obtained in aged Epo-transgenic only but not anymore in old C57BL6 control mice. Click-evoked auditory brainstem response showed similar results. Numbers of spiral ganglion neurons in aged C57BL6 but not Epo-transgenic mice were dramatically reduced mainly in the basal turn, the location of high frequencies. In addition, there was a tendency to better preservation of inner and outer hair cells in Epo-transgenic mice. Hence, Epo's known neuroprotective action effectively suppresses the loss of spiral ganglion cells and probably also hair cells and, thus, development of presbycusis in mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Transglutaminase 2 overexpression induces depressive-like behavior and impaired TrkB signaling in mice

    Science.gov (United States)

    Pandya, Chirayu D; Hoda, Nasrul; Crider, Amanda; Peter, Diya; Kutiyanawalla, Ammar; Kumar, Sanjiv; Ahmed, Anthony O; Turecki, Gustavo; Hernandez, Caterina M; Terry, Alvin V

    2016-01-01

    Serotonin (5-HT) and brain derived neurotrophic factor (BDNF) are two signaling molecules that play important regulatory roles in the development and plasticity of neural circuits that are known to be altered in depression. However, the mechanism by which 5-HT regulates BDNF signaling is unknown. In the present study, we found that 5-HT treatment increases BDNF receptor, TrkB (tropomyosin related kinase B) levels in mouse primary cortical neurons via a Rac1 (RAS-related C3 botulinum toxin substrate 1)-dependent mechanism. Significant increases in the levels of transglutaminase 2 (TG2, which is implicated in transamidation of 5-HT to Rac1) are observed in the mouse prefrontal cortex (PFC) following chronic exposure to stress. We also found that TG2 levels are increased in the postmortem PFC of depressed suicide subjects relative to matched controls. Moreover, in mice, neuronal overexpression of TG2 resulted in the atrophy of neurons and reduced levels of TrkB in the PFC as well as a depressive-like phenotype. Overexpression of TG2 in mouse cortical neurons reduced TrkB levels as a result of impaired endocytosis of TrkB. TG2 inhibition by either a viral particle or pharmacological approach attenuated behavioral deficits caused by chronic unpredictable stress. Moreover, the overexpression of TrkB in the mouse PFC ameliorated the depressive-like phenotype of TG2 overexpressed mice. Taken together, these postmortem and preclinical findings identify TG2 as a critical mediator of the altered TrkB expression and depressive-like behaviors associated with chronic exposure to stress and suggest that TG2 may represent a novel therapeutic target in depression. PMID:27620841

  8. Mild overexpression of Mecp2 in mice causes a higher susceptibility toward seizures.

    Science.gov (United States)

    Bodda, Chiranjeevi; Tantra, Martesa; Mollajew, Rustam; Arunachalam, Jayamuruga P; Laccone, Franco A; Can, Karolina; Rosenberger, Albert; Mironov, Sergej L; Ehrenreich, Hannelore; Mannan, Ashraf U

    2013-07-01

    An intriguing finding about the gene encoding methyl-CpG binding protein 2 (MeCP2) is that the loss-of-function mutations cause Rett syndrome and duplication (gain-of-function) of MECP2 leads to another neurological disorder termed MECP2 duplication syndrome. To ensure proper neurodevelopment, a precise regulation of MeCP2 expression is critical, and any gain or loss of MeCP2 over a narrow threshold level may lead to postnatal neurological impairment. To evaluate MeCP2 dosage effects, we generated Mecp2(WT_EGFP) transgenic (TG) mouse in which MeCP2 (endogenous plus TG) is mildly overexpressed (approximately 1.5×). The TG MeCP2(WT_EGFP) fusion protein is functionally active, as cross breeding of these mice with Mecp2 knockout mice led to alleviation of major phenotypes in the null mutant mice, including premature lethality. To characterize the Mecp2(WT_EGFP) mouse model, we performed an extensive battery of behavioral tests, which revealed that these mice manifest increased aggressiveness and higher pentylenetetrazole (PTZ)-induced seizure propensity. Evaluation of neuronal parameters revealed a reduction in the number of tertiary branching sites and increased spine density in Mecp2(WT_EGFP) transgenic (TG) neurons. Treatment of TG neurons with epileptogenic compound-PTZ led to a marked increase in amplitude and frequency of calcium spikes. Based on our ex vivo and in vivo data, we conclude that epileptic seizures are manifested as the first symptom when MeCP2 is mildly overexpressed in mice. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  9. Mice overexpressing BAFF develop a commensal flora–dependent, IgA-associated nephropathy

    Science.gov (United States)

    McCarthy, Douglas D.; Kujawa, Julie; Wilson, Cheryl; Papandile, Adrian; Poreci, Urjana; Porfilio, Elisa A.; Ward, Lesley; Lawson, Melissa A.E.; Macpherson, Andrew J.; McCoy, Kathy D.; Pei, York; Novak, Lea; Lee, Jeannette Y.; Julian, Bruce A.; Novak, Jan; Ranger, Ann; Gommerman, Jennifer L.; Browning, Jeffrey L.

    2011-01-01

    B cell activation factor of the TNF family (BAFF) is a potent B cell survival factor. BAFF overexpressing transgenic mice (BAFF-Tg mice) exhibit features of autoimmune disease, including B cell hyperplasia and hypergammaglobulinemia, and develop fatal nephritis with age. However, basal serum IgA levels are also elevated, suggesting that the pathology in these mice may be more complex than initially appreciated. Consistent with this, we demonstrate here that BAFF-Tg mice have mesangial deposits of IgA along with high circulating levels of polymeric IgA that is aberrantly glycosylated. Renal disease in BAFF-Tg mice was associated with IgA, because serum IgA was highly elevated in nephritic mice and BAFF-Tg mice with genetic deletion of IgA exhibited less renal pathology. The presence of commensal flora was essential for the elevated serum IgA phenotype, and, unexpectedly, commensal bacteria–reactive IgA antibodies were found in the blood. These data illustrate how excess B cell survival signaling perturbs the normal balance with the microbiota, leading to a breach in the normal mucosal-peripheral compartmentalization. Such breaches may predispose the nonmucosal system to certain immune diseases. Indeed, we found that a subset of patients with IgA nephropathy had elevated serum levels of a proliferation inducing ligand (APRIL), a cytokine related to BAFF. These parallels between BAFF-Tg mice and human IgA nephropathy may provide a new framework to explore connections between mucosal environments and renal pathology. PMID:21881212

  10. Ubiquitous Gasp1 overexpression in mice leads mainly to a hypermuscular phenotype

    Directory of Open Access Journals (Sweden)

    Monestier Olivier

    2012-10-01

    Full Text Available Abstract Background Myostatin, a member of the TGFβ superfamily, is well known as a potent and specific negative regulator of muscle growth. Targeting the myostatin signalling pathway may offer promising therapeutic strategies for the treatment of muscle-wasting disorders. In the last decade, various myostatin-binding proteins have been identified to be able to inhibit myostatin activity. One of these is GASP1 (Growth and Differentiation Factor-Associated Serum Protein-1, a protein containing a follistatin domain as well as multiple domains associated with protease inhibitors. Despite in vitro data, remarkably little is known about in vivo functions of Gasp1. To further address the role of GASP1 during mouse development and in adulthood, we generated a gain-of-function transgenic mouse model that overexpresses Gasp1 under transcriptional control of the human cytomegalovirus immediate-early promoter/enhancer. Results Overexpression of Gasp1 led to an increase in muscle mass observed not before day 15 of postnatal life. The surGasp1 transgenic mice did not display any other gross abnormality. Histological and morphometric analysis of surGasp1 rectus femoris muscles revealed an increase in myofiber size without a corresponding increase in myofiber number. Fiber-type distribution was unaltered. Interestingly, we do not detect a change in total fat mass and lean mass. These results differ from those for myostatin knockout mice, transgenic mice overexpressing the myostatin propeptide or follistatin which exhibit both muscle hypertrophy and hyperplasia, and show minimal fat deposition. Conclusions Altogether, our data give new insight into the in vivo functions of Gasp1. As an extracellular regulatory factor in the myostatin signalling pathway, additional studies on GASP1 and its homolog GASP2 are required to elucidate the crosstalk between the different intrinsic inhibitors of the myostatin.

  11. Trichostatin A suppresses lung adenocarcinoma development in Grg1 overexpressing transgenic mice

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ju, E-mail: ju.liu@sdu.edu.cn [Medical Research Center, Shandong Provincial Qianfoshan Hospital, Shandong University, 16766 Jingshi Road, Jinan (China); Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Li, Yan [Children' s Health Care Center, Shandong Provincial Qianfoshan Hospital, Shandong University, 16766 Jingshi Road, Jinan, Shandong 250014 (China); Dong, Fengyun; Li, Liqun [Medical Research Center, Shandong Provincial Qianfoshan Hospital, Shandong University, 16766 Jingshi Road, Jinan (China); Masuda, Takahiro; Allen, Thaddeus D. [Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Lobe, Corrinne G. [Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Miami Mice Research Corp., MaRS Centre, Heritage Bldg., 101 College Street, Toronto, Ontario M5G 1L7 (Canada)

    2015-08-07

    Trichostatin A (TSA) is a histone deacetylase inhibitor and a potential therapeutic for various malignancies. The in vivo effect of TSA, however, has not been investigated in a transgenic lung cancer model. Previously, we generated transgenic mice with overexpression of Groucho-related-gene 1 (Grg1) and these mice all developed mucinous lung adenocarcinoma. Grg1 is a transcriptional co-repressor protein, the function of which is thought to depend on HDAC activity. However, functions outside the nucleus have also been proposed. We tested the supposition that Grg1-induced tumorigenesis is HDAC-dependent by assaying the therapeutic effect of TSA in the Grg1 transgenic mouse model. We found that TSA significantly inhibited lung tumorigenesis in Grg1 transgenic mice (p < 0.01). TSA did not affect overall Grg1 protein levels, but instead reduced ErbB1 and ErbB2 expression, which are upregulated by Grg1 in the absence of TSA. We confirmed this effect in A549 cells. Furthermore, lapatinib, an inhibitor of both ErbB1 and ErbB2, effectively masked the effect of TSA on the inhibition of A549 cell proliferation and migration, suggesting TSA does work, at least in part, by downregulating ErbB receptors. We additionally found that TSA reduced the expression of VEGF and VEGFR2, but not basic FGF and FGFR1. Our findings indicate that TSA effectively inhibits Grg1-induced lung tumorigenesis through the down-regulation of ErbB1 and ErbB2, as well as reduced VEGF signaling. This suggests TSA and other HDAC inhibitors could have therapeutic value in the treatment of lung cancers with Grg1 overexpression. - Highlights: • TSA suppresses lung tumorigenesis in Grg1 overexpressing transgenic mice. • TSA does not affect overall Grg1 protein levels in the mice and in A549 cells. • TSA reduces ErbB1 and ErbB2 expression in the mice and in A549 cells. • Lapatinib masks TSA-induced inhibition of A549 cell proliferation and migration. • TSA inhibits VEGF signaling, but not basic FGF

  12. Human HMGA2 protein overexpressed in mice induces precursor T-cell lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Efanov, A; Zanesi, N; Coppola, V; Nuovo, G; Bolon, B; Wernicle-Jameson, D; Lagana, A; Hansjuerg, A; Pichiorri, F; Croce, C M

    2014-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a neoplasia of thymocytes characterized by the rapid accumulation of the precursors of T lymphocytes. HMGA2 (high-mobility group AT-hook 2) gene expression is extremely low in normal adult tissues, but it is overexpressed in many tumors. To identify the biological function of HMGA2, we generated transgenic mice carrying the human HMGA2 gene under control of the V H promoter/Eμ enhancer. Approximately 90% of Eμ-HMGA2 transgenic mice became visibly sick between 4 and 8 months due to the onset and progression of a T-ALL-like disease. Characteristic features included severe alopecia (30% of mice); enlarged lymph nodes and spleen; and profound immunological abnormalities (altered cytokine levels, hypoimmunoglobulinemia) leading to reduced immune responsiveness. Immunophenotyping showed accumulation of CD5+CD4+, CD5+CD8+ or CD5+CD8+CD4+ T-cell populations in the spleens and bone marrow of sick animals. These findings show that HMGA2-driven leukemia in mice closely resembles spontaneous human T-ALL, indicating that HMGA2 transgenic mice should serve as an important model for investigating basic mechanisms and potential new therapies of relevance to human T-ALL

  13. Metallothionein-I overexpression decreases brain pathology in transgenic mice with astrocyte-targeted expression of interleukin-6

    DEFF Research Database (Denmark)

    Molinero, Amalia; Penkowa, Milena; Hernández, Joaquín

    2003-01-01

    in this report support the idea that the upregulation of MT-I observed in GFAP-IL6 mice is an important mechanism for coping with brain damage. Thus, GFAP-IL6 mice that were crossed with TgMTI transgenic mice (GFAP-IL6xTgMTI) and overexpressed MT-I in the brain showed a decreased upregulation of cytokines...... such as IL-6 and a diminished recruitment and activation of macrophages and T cells throughout the CNS but mainly in the cerebellum. The GFAP-IL6 mice showed clear evidence of increased oxidative stress, which was significantly decreased by MT-I overexpression. Interestingly, MT-I overexpression increased...

  14. Over-expression of phosphorylated MARCKS in the nicotine-derived nitrosamine ketone induced lung cancer mice

    Directory of Open Access Journals (Sweden)

    Zhen Chen

    2015-03-01

    Full Text Available Lung cancer is the most frequently occurring lethal cancers in men and women population. The aim of the present study is to observe the over-expression pattern of phosphorylated MARCKS in the nicotine-derived nitrosamine ketone (NNK induced lung cancer mice. Pathogen-free female A/J mice were used for the present experiment to induce lung cancer by the carcinogen namely, NNK. At different time intervals namely, 5th, 6th and 7th month after NNK injection, lung tissue samples were collected. Immunohistochemistry in accordance with the immunoblotting techniques were used to confirm the over-expression of phosphorylated MARCKS in the NNK induced lung cancer mice model. The present study concludes that the phosphorylated MARCKS was over-expressed in the NNK induced lung cancer mice during the early stages of lung cancer and it may be used as a tool to detect the lung cancer in the initial stages.

  15. Transgenic mice display hair loss and regrowth overexpressing mutant Hr gene.

    Science.gov (United States)

    Zhu, Kuicheng; Xu, Cunshuan; Zhang, Jintao; Chen, Yingying; Liu, Mengduan

    2017-10-30

    Mutations in the hairless (Hr) gene in both mice and humans have been implicated in the development of congenital atrichia, but the role of Hr in skin and hair follicle (HF) biology remains unknown. Here, we established transgenic mice (TG) overexpressing mutant Hr to investigate its specific role in the development of HF. Three transgenic lines were successfully constructed, and two of them (TG3 and TG8) displayed a pattern of hair loss and regrowth with alternation in the expression of HR protein. The mutant Hr gene inhibited the expression of the endogenous gene in transgenic individuals, which led to the development of alopecia. Interestingly, the hair regrew with the increase in the endogenous expression levels resulting from decreased mutant Hr expression. The findings of our study indicate that the changes in the expression of Hr result in hair loss or regrowth.

  16. [Advances in targeted replacement genome editing in plants].

    Science.gov (United States)

    Wang, Honglin; Zhang, Congsheng; Liu, Changlin; Xie, Chuanxiao

    2017-10-25

    Targeted replacement genome editing refers to DNA modification and engineering technology that could induce and achieve mutations of targeted gene replacement or knockin at a target gene or DNA region. In this review, the principles, implementation methods, factors that influence efficiency and accuracy, and applications of gene replacement editing were summarized and discussed. It provides the reference for gene functional characterization and genetic improvements through gene replacement strategies in higher plant especially crops.

  17. Widespread over-expression of the X chromosome in sterile F₁hybrid mice.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Good

    2010-09-01

    Full Text Available The X chromosome often plays a central role in hybrid male sterility between species, but it is unclear if this reflects underlying regulatory incompatibilities. Here we combine phenotypic data with genome-wide expression data to directly associate aberrant expression patterns with hybrid male sterility between two species of mice. We used a reciprocal cross in which F₁ males are sterile in one direction and fertile in the other direction, allowing us to associate expression differences with sterility rather than with other hybrid phenotypes. We found evidence of extensive over-expression of the X chromosome during spermatogenesis in sterile but not in fertile F₁ hybrid males. Over-expression was most pronounced in genes that are normally expressed after meiosis, consistent with an X chromosome-wide disruption of expression during the later stages of spermatogenesis. This pattern was not a simple consequence of faster evolutionary divergence on the X chromosome, because X-linked expression was highly conserved between the two species. Thus, transcriptional regulation of the X chromosome during spermatogenesis appears particularly sensitive to evolutionary divergence between species. Overall, these data provide evidence for an underlying regulatory basis to reproductive isolation in house mice and underscore the importance of transcriptional regulation of the X chromosome to the evolution of hybrid male sterility.

  18. CRF Receptor Antagonist Astressin-B Reverses and Prevents Alopecia in CRF Over-Expressing Mice

    Science.gov (United States)

    Rivier, Jean; Rivier, Catherine; Craft, Noah; Stenzel-Poore, Mary P.; Taché, Yvette

    2011-01-01

    Corticotropin-releasing factor (CRF) signaling pathways are involved in the stress response, and there is growing evidence supporting hair growth inhibition of murine hair follicle in vivo upon stress exposure. We investigated whether the blockade of CRF receptors influences the development of hair loss in CRF over-expressing (OE)-mice that display phenotypes of Cushing's syndrome and chronic stress, including alopecia. The non-selective CRF receptors antagonist, astressin-B (5 µg/mouse) injected peripherally once a day for 5 days in 4–9 months old CRF-OE alopecic mice induced pigmentation and hair re-growth that was largely retained for over 4 months. In young CRF-OE mice, astressin-B prevented the development of alopecia that occurred in saline-treated mice. Histological examination indicated that alopecic CRF-OE mice had hair follicle atrophy and that astressin-B revived the hair follicle from the telogen to anagen phase. However, astressin-B did not show any effect on the elevated plasma corticosterone levels and the increased weights of adrenal glands and visceral fat in CRF-OE mice. The selective CRF2 receptor antagonist, astressin2-B had moderate effect on pigmentation, but not on hair re-growth. The commercial drug for alopecia, minoxidil only showed partial effect on hair re-growth. These data support the existence of a key molecular switching mechanism triggered by blocking peripheral CRF receptors with an antagonist to reset hair growth in a mouse model of alopecia associated with chronic stress. PMID:21359208

  19. CRF receptor antagonist astressin-B reverses and prevents alopecia in CRF over-expressing mice.

    Directory of Open Access Journals (Sweden)

    Lixin Wang

    2011-02-01

    Full Text Available Corticotropin-releasing factor (CRF signaling pathways are involved in the stress response, and there is growing evidence supporting hair growth inhibition of murine hair follicle in vivo upon stress exposure. We investigated whether the blockade of CRF receptors influences the development of hair loss in CRF over-expressing (OE-mice that display phenotypes of Cushing's syndrome and chronic stress, including alopecia. The non-selective CRF receptors antagonist, astressin-B (5 µg/mouse injected peripherally once a day for 5 days in 4-9 months old CRF-OE alopecic mice induced pigmentation and hair re-growth that was largely retained for over 4 months. In young CRF-OE mice, astressin-B prevented the development of alopecia that occurred in saline-treated mice. Histological examination indicated that alopecic CRF-OE mice had hair follicle atrophy and that astressin-B revived the hair follicle from the telogen to anagen phase. However, astressin-B did not show any effect on the elevated plasma corticosterone levels and the increased weights of adrenal glands and visceral fat in CRF-OE mice. The selective CRF₂ receptor antagonist, astressin₂-B had moderate effect on pigmentation, but not on hair re-growth. The commercial drug for alopecia, minoxidil only showed partial effect on hair re-growth. These data support the existence of a key molecular switching mechanism triggered by blocking peripheral CRF receptors with an antagonist to reset hair growth in a mouse model of alopecia associated with chronic stress.

  20. Trichostatin A suppresses lung adenocarcinoma development in Grg1 overexpressing transgenic mice.

    Science.gov (United States)

    Liu, Ju; Li, Yan; Dong, Fengyun; Li, Liqun; Masuda, Takahiro; Allen, Thaddeus D; Lobe, Corrinne G

    2015-08-07

    Trichostatin A (TSA) is a histone deacetylase inhibitor and a potential therapeutic for various malignancies. The in vivo effect of TSA, however, has not been investigated in a transgenic lung cancer model. Previously, we generated transgenic mice with overexpression of Groucho-related-gene 1 (Grg1) and these mice all developed mucinous lung adenocarcinoma. Grg1 is a transcriptional co-repressor protein, the function of which is thought to depend on HDAC activity. However, functions outside the nucleus have also been proposed. We tested the supposition that Grg1-induced tumorigenesis is HDAC-dependent by assaying the therapeutic effect of TSA in the Grg1 transgenic mouse model. We found that TSA significantly inhibited lung tumorigenesis in Grg1 transgenic mice (p < 0.01). TSA did not affect overall Grg1 protein levels, but instead reduced ErbB1 and ErbB2 expression, which are upregulated by Grg1 in the absence of TSA. We confirmed this effect in A549 cells. Furthermore, lapatinib, an inhibitor of both ErbB1 and ErbB2, effectively masked the effect of TSA on the inhibition of A549 cell proliferation and migration, suggesting TSA does work, at least in part, by downregulating ErbB receptors. We additionally found that TSA reduced the expression of VEGF and VEGFR2, but not basic FGF and FGFR1. Our findings indicate that TSA effectively inhibits Grg1-induced lung tumorigenesis through the down-regulation of ErbB1 and ErbB2, as well as reduced VEGF signaling. This suggests TSA and other HDAC inhibitors could have therapeutic value in the treatment of lung cancers with Grg1 overexpression. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Overexpression of heparanase lowers the amyloid burden in amyloid-β precursor protein transgenic mice.

    Science.gov (United States)

    Jendresen, Charlotte B; Cui, Hao; Zhang, Xiao; Vlodavsky, Israel; Nilsson, Lars N G; Li, Jin-Ping

    2015-02-20

    Heparan sulfate (HS) and HS proteoglycans (HSPGs) colocalize with amyloid-β (Aβ) deposits in Alzheimer disease brain and in Aβ precursor protein (AβPP) transgenic mouse models. Heparanase is an endoglycosidase that specifically degrades the unbranched glycosaminoglycan side chains of HSPGs. The aim of this study was to test the hypothesis that HS and HSPGs are active participators of Aβ pathogenesis in vivo. We therefore generated a double-transgenic mouse model overexpressing both human heparanase and human AβPP harboring the Swedish mutation (tgHpa*Swe). Overexpression of heparanase did not affect AβPP processing because the steady-state levels of Aβ1-40, Aβ1-42, and soluble AβPP β were the same in 2- to 3-month-old double-transgenic tgHpa*Swe and single-transgenic tgSwe mice. In contrast, the Congo red-positive amyloid burden was significantly lower in 15-month-old tgHpa*Swe brain than in tgSwe brain. Likewise, the Aβ burden, measured by Aβx-40 and Aβx-42 immunohistochemistry, was reduced significantly in tgHpa*Swe brain. The intensity of HS-stained plaques correlated with the Aβx-42 burden and was reduced in tgHpa*Swe mice. Moreover, the HS-like molecule heparin facilitated Aβ1-42-aggregation in an in vitro Thioflavin T assay. The findings suggest that HSPGs contribute to amyloid deposition in tgSwe mice by increasing Aβ fibril formation because heparanase-induced fragmentation of HS led to a reduced amyloid burden. Therefore, drugs interfering with Aβ-HSPG interactions might be a potential strategy for Alzheimer disease treatment. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Bmi1 overexpression in the cerebellar granule cell lineage of mice affects cell proliferation and survival without initiating medulloblastoma formation

    Directory of Open Access Journals (Sweden)

    Hourinaz Behesti

    2013-01-01

    BMI1 is a potent inducer of neural stem cell self-renewal and neural progenitor cell proliferation during development and in adult tissue homeostasis. It is overexpressed in numerous human cancers – including medulloblastomas, in which its functional role is unclear. We generated transgenic mouse lines with targeted overexpression of Bmi1 in the cerebellar granule cell lineage, a cell type that has been shown to act as a cell of origin for medulloblastomas. Overexpression of Bmi1 in granule cell progenitors (GCPs led to a decrease in cerebellar size due to decreased GCP proliferation and repression of the expression of cyclin genes, whereas Bmi1 overexpression in postmitotic granule cells improved cell survival in response to stress by altering the expression of genes in the mitochondrial cell death pathway and of Myc and Lef-1. Although no medulloblastomas developed in ageing cohorts of transgenic mice, crosses with Trp53−/− mice resulted in a low incidence of medulloblastoma formation. Furthermore, analysis of a large collection of primary human medulloblastomas revealed that tumours with a BMI1high TP53low molecular profile are significantly enriched in Group 4 human medulloblastomas. Our data suggest that different levels and timing of Bmi1 overexpression yield distinct cellular outcomes within the same cellular lineage. Importantly, Bmi1 overexpression at the GCP stage does not induce tumour formation, suggesting that BMI1 overexpression in GCP-derived human medulloblastomas probably occurs during later stages of oncogenesis and might serve to enhance tumour cell survival.

  3. Overexpression of Shox2 Leads to Congenital Dysplasia of the Temporomandibular Joint in Mice

    Directory of Open Access Journals (Sweden)

    Xihai Li

    2014-07-01

    Full Text Available Our previous study reported that inactivation of Shox2 led to dysplasia and ankylosis of the temporomandibular joint (TMJ, and that replacing Shox2 with human Shox partially rescued the phenotype with a prematurely worn out articular disc. However, the mechanisms of Shox2 activity in TMJ development remain to be elucidated. In this study, we investigated the molecular and cellular basis for the congenital dysplasia of TMJ in Wnt1-Cre; pMes-stop Shox2 mice. We found that condyle and glenoid fossa dysplasia occurs primarily in the second week after the birth. The dysplastic TMJ of Wnt1-Cre; pMes-stop Shox2 mice exhibits a loss of Collagen type I, Collagen type II, Ihh and Gli2. In situ zymography and immunohistochemistry further demonstrate an up-regulation of matrix metalloproteinases (MMPs, MMP9 and MMP13, accompanied by a significantly increased cell apoptosis. In addition, the cell proliferation and expressions of Sox9, Runx2 and Ihh are no different in the embryonic TMJ between the wild type and mutant mice. Our results show that overexpression of Shox2 leads to the loss of extracellular matrix and the increase of cell apoptosis in TMJ dysplasia by up-regulating MMPs and down-regulating the Ihh signaling pathway.

  4. Overexpression of a transcription factor LYL1 induces T- and B-cell lymphoma in mice.

    Science.gov (United States)

    Zhong, Y; Jiang, L; Hiai, H; Toyokuni, S; Yamada, Y

    2007-10-18

    LYL1, a member of the class II basic helix-loop-helix transcription factors, is aberrantly expressed in a fraction of human T-cell acute lymphoblastic leukemia. Here, we generated transgenic mice ubiquitously overexpressing LYL1 using a construct expressing full-length cDNA driven by a human elongation factor 1alpha promoter. Four independent lines exhibiting high LYL1 expression were established. Of these transgenic mice, 96% displayed loss of hair with a short kinked tail. Furthermore, 30% of them developed malignant lymphoma, with an average latent period of 352 days. In these mice, histological examination revealed tumor cell infiltration in multiple organs and immunohistochemical analysis showed that the infiltrated tumor cells were either CD3 or CD45R/B220-positive; fluorescence-activated cell sorter analysis indicated that each tumor consisted either of mainly CD4, CD8 double-positive T cells or mature B cells; the clonality of LYL1-induced lymphoma was confirmed by T-cell receptor rearrangement and immunoglobulin heavy-chain gene rearrangement analyses. Mammalian two-hybrid analysis and luciferase assay suggested that excess LYL1 blocked the dimerization of E2A and thus inhibited the regulatory activity of E2A on the CD4 promoter. Reverse transcription-polymerase chain reaction results showed that the expression of certain E2A/HEB target genes was downregulated. Taken together, our results provide direct evidence that aberrant expression of LYL1 plays a role in lymphomagenesis.

  5. Mitogenic signaling pathways in the liver of growth hormone (GH)-overexpressing mice during the growth period.

    Science.gov (United States)

    Martinez, Carolina S; Piazza, Verónica G; González, Lorena; Fang, Yimin; Bartke, Andrzej; Turynl, Danie; Miquet, Johanna G; Sotelo, Ana I

    2016-01-01

    Growth hormone (GH) is a pleiotropic hormone that triggers STATs, ERK1/2 and Akt signaling, related to cell growth and proliferation. Transgenic mice overexpressing GH present increased body size, with a disproportionate liver enlargement due to hypertrophy and hyperplasia of the hepatocytes. We had described enhanced mitogenic signaling in liver of young adult transgenic mice. We now evaluate the activation of these signaling cascades during the growth period and relate them to the morphological alterations found. Signaling mediators, cell cycle regulators and transcription factors involved in cellular growth in the liver of GH-overexpressing growing mice were assessed by immunoblotting, RT-qPCR and immunohistochemistry. Hepatocyte enlargement can be seen as early as 2-weeks of age in GH-overexpressing animals, although it is more pronounced in young adults. Levels of cell cycle mediators PCNA and cyclin D1, and transcription factor c-Jun increase with age in transgenic mice with no changes in normal mice, whereas c-Myc levels are higher in 2-week-old transgenic animals and cyclin E levels decline with age for both genotypes. STAT3, Akt and GSK3 present higher activation in the adult transgenic mice than in the growing animals, while for c-Src and mTOR, phosphorylation in GH-overexpressing mice is higher than in control siblings at 4 and 9 weeks of age. No significant changes are observed for ERK1/2, neither by age or genotype. Thus, the majority of the mitogenic signaling pathways are gradually up-regulated in the liver of GH-transgenic mice, giving rise to the hepatic morphological changes these mice exhibit.

  6. Macrophage overexpression of matrix metalloproteinase-9 in aged mice improves diastolic physiology and cardiac wound healing after myocardial infarction.

    Science.gov (United States)

    Meschiari, Cesar A; Jung, Mira; Iyer, Rugmani Padmanabhan; Yabluchanskiy, Andriy; Toba, Hiroe; Garrett, Michael R; Lindsey, Merry L

    2018-02-01

    Matrix metalloproteinase (MMP)-9 increases in the myocardium with advanced age and after myocardial infarction (MI). Because young transgenic (TG) mice overexpressing human MMP-9 only in macrophages show better outcomes post-MI, whereas aged TG mice show a worse aging phenotype, we wanted to evaluate the effect of aging superimposed on MI to see if the detrimental effect of aging counteracted the benefits of macrophage MMP-9 overexpression. We used 17- to 28-mo-old male and female C57BL/6J wild-type (WT) and TG mice ( n = 10-21 mice/group) to evaluate the effects of aging superimposed on MI. Despite similar infarct areas and mortality rates at day 7 post-MI, aging TG mice showed improved diastolic properties and remodeling index compared with WT mice (both P wound healing through direct and indirect mechanisms to improve diastolic physiology and remodeling. NEW & NOTEWORTHY Aging mice with macrophage overexpression of matrix metalloproteinase-9 have increased macrophage numbers 7 days after myocardial infarction, resulting in improved diastolic physiology and left ventricular remodeling through effects on cardiac wound healing.

  7. Transgenic overexpression of protein targeting to glycogen markedly increases adipocytic glycogen storage in mice.

    Science.gov (United States)

    Jurczak, Michael J; Danos, Arpad M; Rehrmann, Victoria R; Allison, Margaret B; Greenberg, Cynthia C; Brady, Matthew J

    2007-03-01

    Adipocytes express the rate-limiting enzymes required for glycogen metabolism and increase glycogen synthesis in response to insulin. However, the physiological function of adipocytic glycogen in vivo is unclear, due in part to the low absolute levels and the apparent biophysical constraints of adipocyte morphology on glycogen accumulation. To further study the regulation of glycogen metabolism in adipose tissue, transgenic mice were generated that overexpressed the protein phosphatase-1 (PP1) glycogen-targeting subunit (PTG) driven by the adipocyte fatty acid binding protein (aP2) promoter. Exogenous PTG was detected in gonadal, perirenal, and brown fat depots, but it was not detected in any other tissue examined. PTG overexpression resulted in a modest redistribution of PP1 to glycogen particles, corresponding to a threefold increase in the glycogen synthase activity ratio. Glycogen synthase protein levels were also increased twofold, resulting in a combined greater than sixfold enhancement of basal glycogen synthase specific activity. Adipocytic glycogen levels were increased 200- to 400-fold in transgenic animals, and this increase was maintained to 1 yr of age. In contrast, lipid metabolism in transgenic adipose tissue was not significantly altered, as assessed by lipogenic rates, weight gain on normal or high-fat diets, or circulating free fatty acid levels after a fast. However, circulating and adipocytic leptin levels were doubled in transgenic animals, whereas adiponectin expression was unchanged. Cumulatively, these data indicate that murine adipocytes are capable of storing far higher levels of glycogen than previously reported. Furthermore, these results were obtained by overexpression of an endogenous adipocytic protein, suggesting that mechanisms may exist in vivo to maintain adipocytic glycogen storage at a physiological set point.

  8. Decreased Cocaine Motor Sensitization and Self-Administration in Mice Overexpressing Cannabinoid CB2 Receptors

    Science.gov (United States)

    Aracil-Fernández, Auxiliadora; Trigo, José M; García-Gutiérrez, María S; Ortega-Álvaro, Antonio; Ternianov, Alexander; Navarro, Daniela; Robledo, Patricia; Berbel, Pere; Maldonado, Rafael; Manzanares, Jorge

    2012-01-01

    The potential involvement of the cannabinoid CB2 receptors (CB2r) in the adaptive responses induced by cocaine was studied in transgenic mice overexpressing the CB2r (CB2xP) and in wild-type (WT) littermates. For this purpose, the acute and sensitized locomotor responses to cocaine, conditioned place preference, and cocaine intravenous self-administration were evaluated. In addition, we assessed whether CB2r were localized in neurons and/or astrocytes, and whether they colocalized with dopamine D1 and D2 receptors (D1Dr and D2Dr). Dopamine (DA) extracellular levels in the nucleus accumbens (NAcc), and gene expression of tyrosine hydroxylase (TH) and DA transporter (DAT) in the ventral tegmental area (VTA), and μ-opioid and cannabinoid CB1 receptors in the NAcc were also studied in both genotypes. CB2xP mice showed decreased motor response to acute administration of cocaine (10–20 mg/kg) and cocaine-induced motor sensitization compared with WT mice. CB2xP mice presented cocaine-induced conditioned place aversion and self-administered less cocaine than WT mice. CB2r were found in neurons and astrocytes and colocalized with D2Dr in the VTA and NAcc. No significant differences in extracellular DA levels in the NAcc were observed between genotypes after cocaine administration. Under baseline conditions, TH and DAT gene expression was higher and μ-opioid receptor gene expression was lower in CB2xP than in WT mice. However, both genotypes showed similar changes in TH and μ-opioid receptor gene expression after cocaine challenge independently of the pretreatment received. Importantly, the cocaine challenge decreased DAT gene expression to a lesser extent in cocaine-pretreated CB2xP than in cocaine-pretreated WT mice. These results revealed that CB2r are involved in cocaine motor responses and cocaine self-administration, suggesting that this receptor could represent a promising target to develop novel treatments for cocaine addiction. PMID:22414816

  9. Metabolomic Analysis of the Skeletal Muscle of Mice Overexpressing PGC-1α.

    Directory of Open Access Journals (Sweden)

    Yukino Hatazawa

    Full Text Available Peroxisome proliferator-activated receptor (PPAR γ coactivator 1α (PGC-1α is a coactivator of various nuclear receptors and other transcription factors whose expression increases in the skeletal muscle during exercise. We have previously made transgenic mice overexpressing PGC-1α in the skeletal muscle (PGC-1α-Tg mice. PGC-1α upregulates the expression of genes associated with red fibers, mitochondrial function, fatty acid oxidation, and branched chain amino acid (BCAA degradation. However, global analyses of the actual metabolic products have not been investigated. In this study, we conducted metabolomic analysis of the skeletal muscle in PGC-1α-Tg mice by capillary electrophoresis with electrospray ionization time-of-flight mass spectrometry. Principal component analysis and hierarchical cluster analysis showed clearly distinguishable changes in the metabolites between PGC-1α-Tg and wild-type control mice. Changes were observed in metabolite levels of various metabolic pathways such as the TCA cycle, pentose phosphate pathway, nucleotide synthesis, purine nucleotide cycle, and amino acid metabolism, including BCAA and β-alanine. Namely, metabolic products of the TCA cycle increased in PGC-1α-Tg mice, with increased levels of citrate (2.3-fold, succinate (2.2-fold, fumarate (2.8-fold, and malate (2.3-fold observed. Metabolic products associated with the pentose phosphate pathway and nucleotide biosynthesis also increased in PGC-1α-Tg mice. Meanwhile, BCAA levels decreased (Val, 0.7-fold; Leu, 0.8-fold; and Ile, 0.7-fold, and Glu (3.1-fold and Asp (2.2-fold levels increased. Levels of β-alanine and related metabolites were markedly decreased in PGC-1α-Tg mice. Coordinated regulation of the TCA cycle and amino acid metabolism, including BCAA, suggests that PGC-1α plays important roles in energy metabolism. Moreover, our metabolomics data showing the activation of the purine nucleotide pathway, malate-aspartate shuttle, as well as

  10. Phospholamban overexpression in mice causes a centronuclear myopathy-like phenotype

    Directory of Open Access Journals (Sweden)

    Val A. Fajardo

    2015-08-01

    Full Text Available Centronuclear myopathy (CNM is a congenital myopathy that is histopathologically characterized by centrally located nuclei, central aggregation of oxidative activity, and type I fiber predominance and hypotrophy. Here, we obtained commercially available mice overexpressing phospholamban (PlnOE, a well-known inhibitor of sarco(endoplasmic reticulum Ca2+-ATPases (SERCAs, in their slow-twitch type I skeletal muscle fibers to determine the effects on SERCA function. As expected with a 6- to 7-fold overexpression of phospholamban, SERCA dysfunction was evident in PlnOE muscles, with marked reductions in rates of Ca2+ uptake, maximal ATPase activity and the apparent affinity of SERCA for Ca2+. However, our most significant discovery was that the soleus and gluteus minimus muscles from the PlnOE mice displayed overt signs of myopathy: they histopathologically resembled human CNM, with centrally located nuclei, central aggregation of oxidative activity, type I fiber predominance and hypotrophy, progressive fibrosis and muscle weakness. This phenotype is associated with significant upregulation of muscle sarcolipin and dynamin 2, increased Ca2+-activated proteolysis, oxidative stress and protein nitrosylation. Moreover, in our assessment of muscle biopsies from three human CNM patients, we found a significant 53% reduction in SERCA activity and increases in both total and monomeric PLN content compared with five healthy subjects, thereby justifying future studies with more CNM patients. Altogether, our results suggest that the commercially available PlnOE mouse phenotypically resembles human CNM and could be used as a model to test potential mechanisms and therapeutic strategies. To date, there is no cure for CNM and our results suggest that targeting SERCA function, which has already been shown to be an effective therapeutic target for murine muscular dystrophy and human cardiomyopathy, might represent a novel therapeutic strategy to combat CNM.

  11. Phospholamban overexpression in mice causes a centronuclear myopathy-like phenotype

    Science.gov (United States)

    Fajardo, Val A.; Bombardier, Eric; McMillan, Elliott; Tran, Khanh; Wadsworth, Brennan J.; Gamu, Daniel; Hopf, Andrew; Vigna, Chris; Smith, Ian C.; Bellissimo, Catherine; Michel, Robin N.; Tarnopolsky, Mark A.; Quadrilatero, Joe; Tupling, A. Russell

    2015-01-01

    ABSTRACT Centronuclear myopathy (CNM) is a congenital myopathy that is histopathologically characterized by centrally located nuclei, central aggregation of oxidative activity, and type I fiber predominance and hypotrophy. Here, we obtained commercially available mice overexpressing phospholamban (PlnOE), a well-known inhibitor of sarco(endo)plasmic reticulum Ca2+-ATPases (SERCAs), in their slow-twitch type I skeletal muscle fibers to determine the effects on SERCA function. As expected with a 6- to 7-fold overexpression of phospholamban, SERCA dysfunction was evident in PlnOE muscles, with marked reductions in rates of Ca2+ uptake, maximal ATPase activity and the apparent affinity of SERCA for Ca2+. However, our most significant discovery was that the soleus and gluteus minimus muscles from the PlnOE mice displayed overt signs of myopathy: they histopathologically resembled human CNM, with centrally located nuclei, central aggregation of oxidative activity, type I fiber predominance and hypotrophy, progressive fibrosis and muscle weakness. This phenotype is associated with significant upregulation of muscle sarcolipin and dynamin 2, increased Ca2+-activated proteolysis, oxidative stress and protein nitrosylation. Moreover, in our assessment of muscle biopsies from three human CNM patients, we found a significant 53% reduction in SERCA activity and increases in both total and monomeric PLN content compared with five healthy subjects, thereby justifying future studies with more CNM patients. Altogether, our results suggest that the commercially available PlnOE mouse phenotypically resembles human CNM and could be used as a model to test potential mechanisms and therapeutic strategies. To date, there is no cure for CNM and our results suggest that targeting SERCA function, which has already been shown to be an effective therapeutic target for murine muscular dystrophy and human cardiomyopathy, might represent a novel therapeutic strategy to combat CNM. PMID:26035394

  12. Sarcolipin deletion exacerbates soleus muscle atrophy and weakness in phospholamban overexpressing mice.

    Directory of Open Access Journals (Sweden)

    Val A Fajardo

    Full Text Available Sarcolipin (SLN and phospholamban (PLN are two small proteins that regulate the sarco(endoplasmic reticulum Ca2+-ATPase pumps. In a recent study, we discovered that Pln overexpression (PlnOE in slow-twitch type I skeletal muscle fibers drastically impaired SERCA function and caused a centronuclear myopathy-like phenotype, severe muscle atrophy and weakness, and an 8 to 9-fold upregulation of SLN protein in the soleus muscles. Here, we sought to determine the physiological role of SLN upregulation, and based on its role as a SERCA inhibitor, we hypothesized that it would represent a maladaptive response that contributes to the SERCA dysfunction and the overall myopathy observed in the PlnOE mice. To this end, we crossed Sln-null (SlnKO mice with PlnOE mice to generate a PlnOE/SlnKO mouse colony and assessed SERCA function, CNM pathology, in vitro contractility, muscle mass, calcineurin signaling, daily activity and food intake, and proteolytic enzyme activity. Our results indicate that genetic deletion of Sln did not improve SERCA function nor rescue the CNM phenotype, but did result in exacerbated muscle atrophy and weakness, due to a failure to induce type II fiber compensatory hypertrophy and a reduction in total myofiber count. Mechanistically, our findings suggest that impaired calcineurin activation and resultant decreased expression of stabilin-2, and/or impaired autophagic signaling could be involved. Future studies should examine these possibilities. In conclusion, our study demonstrates the importance of SLN upregulation in combating muscle myopathy in the PlnOE mice, and since SLN is upregulated across several myopathies, our findings may reveal SLN as a novel and universal therapeutic target.

  13. Sarcolipin deletion exacerbates soleus muscle atrophy and weakness in phospholamban overexpressing mice.

    Science.gov (United States)

    Fajardo, Val A; Gamu, Daniel; Mitchell, Andrew; Bloemberg, Darin; Bombardier, Eric; Chambers, Paige J; Bellissimo, Catherine; Quadrilatero, Joe; Tupling, A Russell

    2017-01-01

    Sarcolipin (SLN) and phospholamban (PLN) are two small proteins that regulate the sarco(endo)plasmic reticulum Ca2+-ATPase pumps. In a recent study, we discovered that Pln overexpression (PlnOE) in slow-twitch type I skeletal muscle fibers drastically impaired SERCA function and caused a centronuclear myopathy-like phenotype, severe muscle atrophy and weakness, and an 8 to 9-fold upregulation of SLN protein in the soleus muscles. Here, we sought to determine the physiological role of SLN upregulation, and based on its role as a SERCA inhibitor, we hypothesized that it would represent a maladaptive response that contributes to the SERCA dysfunction and the overall myopathy observed in the PlnOE mice. To this end, we crossed Sln-null (SlnKO) mice with PlnOE mice to generate a PlnOE/SlnKO mouse colony and assessed SERCA function, CNM pathology, in vitro contractility, muscle mass, calcineurin signaling, daily activity and food intake, and proteolytic enzyme activity. Our results indicate that genetic deletion of Sln did not improve SERCA function nor rescue the CNM phenotype, but did result in exacerbated muscle atrophy and weakness, due to a failure to induce type II fiber compensatory hypertrophy and a reduction in total myofiber count. Mechanistically, our findings suggest that impaired calcineurin activation and resultant decreased expression of stabilin-2, and/or impaired autophagic signaling could be involved. Future studies should examine these possibilities. In conclusion, our study demonstrates the importance of SLN upregulation in combating muscle myopathy in the PlnOE mice, and since SLN is upregulated across several myopathies, our findings may reveal SLN as a novel and universal therapeutic target.

  14. Hematopoietic overexpression of Cyp27a1 reduces hepatic inflammation independently of 27-hydroxycholesterol levels in Ldlr(-/-) mice.

    Science.gov (United States)

    Hendrikx, Tim; Jeurissen, Mike L J; Bieghs, Veerle; Walenbergh, Sofie M A; van Gorp, Patrick J; Verheyen, Fons; Houben, Tom; Guichot, Yasmin Dias; Gijbels, Marion J J; Leitersdorf, Eran; Hofker, Marten H; Lütjohann, Dieter; Shiri-Sverdlov, Ronit

    2015-02-01

    Non-alcoholic steatohepatitis (NASH) is characterized by hepatic lipid accumulation and inflammation. Currently, the underlying mechanisms, leading to hepatic inflammation, are still unknown. The breakdown of free cholesterol inside Kupffer cells (KCs) by the mitochondrial enzyme CYP27A1 produces 27-hydroxycholesterol (27HC). We recently demonstrated that administration of 27HC to hyperlipidemic mice reduced hepatic inflammation. In line, hematopoietic deletion of Cyp27a1 resulted in increased hepatic inflammation. In the current manuscript, the effect of hematopoietic overexpression of Cyp27a1 on the development of NASH and cholesterol trafficking was investigated. We hypothesized that Cyp27a1 overexpression in KCs will lead to reduced hepatic inflammation. Irradiated Ldlr(-/-) mice were transplanted (tp) with bone marrow from mice overexpressing Cyp27a1 (Cyp27a1(over)) and wild type (Wt) mice and fed either chow or a high-fat, high-cholesterol (HFC) diet for 3 months. Additionally, gene expression was assessed in bone marrow-derived macrophages (BMDM) from Cyp27a1(over) and Wt mice. In line with our hypothesis, hepatic inflammation in HFC-fed Cyp27a1(over)-tp mice was reduced and KCs were less foamy compared to Wt-tp mice. Remarkably, these changes occurred even though plasma and liver levels of 27HC did not differ between both groups. BMDM from Cyp27a1(over) mice revealed reduced inflammatory gene expression and increased expression of cholesterol transporters compared to Wt BMDM after lipopolysaccharide (LPS) stimulation. Our data suggest that overexpression of Cyp27a1 in KCs reduces hepatic inflammation independently of 27HC levels in plasma and liver, further pointing towards KCs as specific target for improving the therapy of NASH. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  15. Over-expression of Follistatin-like 3 attenuates fat accumulation and improves insulin sensitivity in mice

    DEFF Research Database (Denmark)

    Brandt, Claus; Hansen, Rasmus Hvass; Hansen, Jakob Bondo

    2015-01-01

    -fat feeding. Body weight, food intake, fat accumulation by MR scanning, and glucose, insulin and glucagon tolerance were evaluated, as was the response in body weight and metabolic parameters to 24h fasting. Effects of fstl3 on pancreatic insulin and glucagon content, and pancreatic islet morphology were...... through systemic fstl3 over-expression protects against diet-induced obesity and insulin resistance. METHODS: Fstl3 was over-expressed by DNA electrotransfer in tibialis anterior, quadriceps and gastrocnemius muscles in female C57BL/C mice, and the mice were subsequently randomized to chow or high....../glucagon ratio. Accordingly, fstl3 transfection improved counter-regulation to 24h fasting. CONCLUSION: Fstl3 over-expression regulates insulin and glucagon sensitivities through increased muscular insulin action, as well as increased hepatic glucagon sensitivity and pancreatic glucagon content....

  16. Hepatic overexpression of Abcb11 in mice promotes the conservation of bile acids within the enterohepatic circulation

    NARCIS (Netherlands)

    Henkel, Anne S.; Gooijert, Karin E. R.; Havinga, Rick; Boverhof, Renze; Green, Richard M.; Verkade, Henkjan J.

    Henkel AS, Gooijert KE, Havinga R, Boverhof R, Green RM, Verkade HJ. Hepatic overexpression of Abcb11 in mice promotes the conservation of bile acids within the enterohepatic circulation. Am J Physiol Gastrointest Liver Physiol 304: G221-G226, 2013. First published November 8, 2012;

  17. Overexpression of TGF-ß1 in macrophages reduces and stabilizes atherosclerotic plaques in ApoE-deficient mice.

    Directory of Open Access Journals (Sweden)

    Kurt Reifenberg

    Full Text Available Although macrophages represent the hallmark of both human and murine atherosclerotic lesions and have been shown to express TGF-ß1 (transforming growth factor β1 and its receptors, it has so far not been experimentally addressed whether the pleiotropic cytokine TGF-ß1 may influence atherogenesis by a macrophage specific mechanism. We developed transgenic mice with macrophage specific TGF-ß1 overexpression, crossed the transgenics to the atherosclerotic ApoE (apolipoprotein E knock-out strain and quantitatively analyzed both atherosclerotic lesion development and composition of the resulting double mutants. Compared with control ApoE(-/- mice, animals with macrophage specific TGF-ß1 overexpression developed significantly less atherosclerosis after 24 weeks on the WTD (Western type diet as indicated by aortic plaque area en face (p<0.05. Reduced atherosclerotic lesion development was associated with significantly less macrophages (p<0.05 after both 8 and 24 weeks on the WTD, significantly more smooth muscle cells (SMCs; p<0.01 after 24 weeks on the WTD, significantly more collagen (p<0.01 and p<0.05 after 16 and 24 weeks on the WTD, respectively without significant differences of inner aortic arch intima thickness or the number of total macrophages in the mice pointing to a plaque stabilizing effect of macrophage-specific TGF-ß1 overexpression. Our data shows that macrophage specific TGF-ß1 overexpression reduces and stabilizes atherosclerotic plaques in ApoE-deficient mice.

  18. Thrombospondin-2 overexpression in the skin of transgenic mice reduces the susceptibility to chemically induced multistep skin carcinogenesis.

    Science.gov (United States)

    Kunstfeld, Rainer; Hawighorst, Thomas; Streit, Michael; Hong, Young-Kwon; Nguyen, Lynh; Brown, Lawrence F; Detmar, Michael

    2014-05-01

    We have previously reported stromal upregulation of the endogenous angiogenesis inhibitor thrombospondin-2 (TSP-2) during multistep carcinogenesis, and we found accelerated and enhanced skin angiogenesis and carcinogenesis in TSP-2 deficient mice. To investigate whether enhanced levels of TSP-2 might protect from skin cancer development. We established transgenic mice with targeted overexpression of TSP-2 in the skin and subjected hemizygous TSP-2 transgenic mice and their wild-type littermates to a chemical skin carcinogenesis regimen. TSP-2 transgenic mice showed a significantly delayed onset of tumor formation compared to wild-type mice, whereas the ratio of malignant conversion to squamous cell carcinomas was comparable in both genotypes. Computer-assisted morphometric analysis of blood vessels revealed pronounced tumor angiogenesis already in the early stages of carcinogenesis in wild type mice. TSP-2 overexpression significantly reduced tumor blood vessel density in transgenic mice but had no overt effect on LYVE-1 positive lymphatic vessels. The percentage of desmin surrounded, mature tumor-associated blood vessels and the degree of epithelial differentiation remained unaffected. The antiangiogenic effect of transgenic TSP-2 was accompanied by a significantly increased number of apoptotic tumor cells in transgenic mice. Our results demonstrate that enhanced levels of TSP-2 in the skin result in reduced susceptibility to chemically-induced skin carcinogenesis and identify TSP-2 as a new target for the prevention of skin cancer. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Metalloproteinases control brain inflammation induced by pertussis toxin in mice overexpressing the chemokine CCL2 in the central nervous system

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Buist, Richard; Sun, Xue-Jun

    2006-01-01

    in the perivascular space in brains of transgenic (Tg) mice that overexpress CCL2 under control of a CNS-specific promoter. The Tg mice show no clinical symptoms, even though leukocytes have crossed the endothelial basement membrane. Pertussis toxin (PTx) given i.p. induced encephalopathy and weight loss in Tg mice...... symptoms. Metalloproteinase (MPs) enzymes are implicated in leukocyte infiltration in neuroinflammation. Unmanipulated Tg mice had elevated expression of tissue inhibitor of metalloproteinase-1, matrix metalloproteinase (MMP)-10, and -12 mRNA in the brain. PTx further induced expression of tissue inhibitor...... of metalloproteinase-1, metalloproteinase disintegrins-12, MMP-8, and -10 in brains of Tg mice. Levels of the microglial-associated MP MMP-15 were not affected in control or PTx-treated Tg mice. PTx also up-regulated expression of proinflammatory cytokines IL-1beta and TNF-alpha mRNA in Tg CNS. Weight loss...

  20. Lens Crystallin Modifications and Cataract in Transgenic Mice Overexpressing Acylpeptide Hydrolase*

    Science.gov (United States)

    Santhoshkumar, Puttur; Xie, Leike; Raju, Murugesan; Reneker, Lixing; Sharma, K. Krishna

    2014-01-01

    The accumulation of crystallin fragments in vivo and their subsequent interaction with crystallins are responsible, in part, for protein aggregation in cataracts. Transgenic mice overexpressing acylpeptide hydrolase (APH) specifically in the lens were prepared to test the role of protease in the generation and accumulation of peptides. Cataract development was seen at various postnatal days in the majority of mice expressing active APH (wt-APH). Cataract onset and severity of the cataracts correlated with the APH protein levels. Lens opacity occurred when APH protein levels were >2.6% of the total lens protein and the specific activity, assayed using Ac-Ala-p-nitroanilide substrate, was >1 unit. Transgenic mice carrying inactive APH (mt-APH) did not develop cataract. Cataract development also correlated with N-terminal cleavage of the APH to generate a 57-kDa protein, along with an increased accumulation of low molecular weight (LMW) peptides, similar to those found in aging human and cataract lenses. Nontransgenic mouse lens proteins incubated with purified wt-APH in vitro resulted in a >20% increase in LMW peptides. Crystallin modifications and cleavage were quite dramatic in transgenic mouse lenses with mature cataract. Affected lenses showed capsule rupture at the posterior pole, with expulsion of the lens nucleus and degenerating fiber cells. Our study suggests that the cleaved APH fragment might exert catalytic activity against crystallins, resulting in the accumulation of distinct LMW peptides that promote protein aggregation in lenses expressing wt-APH. The APH transgenic model we developed will enable in vivo testing of the roles of crystallin fragments in protein aggregation. PMID:24554718

  1. Metallothionein-I overexpression decreases brain pathology in transgenic mice with astrocyte-targeted expression of interleukin-6

    DEFF Research Database (Denmark)

    Molinero, Amalia; Penkowa, Milena; Hernández, Joaquín

    2003-01-01

    Transgenic expression of interleukin-6 (IL-6) in the CNS under the control of the glial fibrillary acidic protein (GFAP) gene promoter (GFAP-IL6 mice) causes significant damage and alters the expression of many genes, including a dramatic upregulation of metallothionein-I (MT-I). The findings...... in this report support the idea that the upregulation of MT-I observed in GFAP-IL6 mice is an important mechanism for coping with brain damage. Thus, GFAP-IL6 mice that were crossed with TgMTI transgenic mice (GFAP-IL6xTgMTI) and overexpressed MT-I in the brain showed a decreased upregulation of cytokines...... such as IL-6 and a diminished recruitment and activation of macrophages and T cells throughout the CNS but mainly in the cerebellum. The GFAP-IL6 mice showed clear evidence of increased oxidative stress, which was significantly decreased by MT-I overexpression. Interestingly, MT-I overexpression increased...

  2. Conditional over-expression of PITX1 causes skeletal muscle dystrophy in mice.

    Science.gov (United States)

    Pandey, Sachchida N; Cabotage, Jennifer; Shi, Rongye; Dixit, Manjusha; Sutherland, Margret; Liu, Jian; Muger, Stephanie; Harper, Scott Q; Nagaraju, Kanneboyina; Chen, Yi-Wen

    2012-07-01

    Paired-like homeodomain transcription factor 1 (PITX1) was specifically up-regulated in patients with facioscapulohumeral muscular dystrophy (FSHD) by comparing the genome-wide mRNA expression profiles of 12 neuromuscular disorders. In addition, it is the only known direct transcriptional target of the double homeobox protein 4 (DUX4) of which aberrant expression has been shown to be the cause of FSHD. To test the hypothesis that up-regulation of PITX1 contributes to the skeletal muscle atrophy seen in patients with FSHD, we generated a tet-repressible muscle-specific Pitx1 transgenic mouse model in which expression of PITX1 in skeletal muscle can be controlled by oral administration of doxycycline. After PITX1 was over-expressed in the skeletal muscle for 5 weeks, the mice exhibited significant loss of body weight and muscle mass, decreased muscle strength, and reduction of muscle fiber diameters. Among the muscles examined, the tibialis anterior, gastrocnemius, quadricep, bicep, tricep and deltoid showed significant reduction of muscle mass, while the soleus, masseter and diaphragm muscles were not affected. The most prominent pathological change was the development of atrophic muscle fibers with mild necrosis and inflammatory infiltration. The affected myofibers stained heavily with NADH-TR with the strongest staining in angular-shaped atrophic fibers. Some of the atrophic fibers were also positive for embryonic myosin heavy chain using immunohistochemistry. Immunoblotting showed that the p53 was up-regulated in the muscles over-expressing PITX1. The results suggest that the up-regulation of PITX1 followed by activation of p53-dependent pathways may play a major role in the muscle atrophy developed in the mouse model.

  3. Conditional over-expression of PITX1 causes skeletal muscle dystrophy in mice

    Directory of Open Access Journals (Sweden)

    Sachchida N. Pandey

    2012-05-01

    Paired-like homeodomain transcription factor 1 (PITX1 was specifically up-regulated in patients with facioscapulohumeral muscular dystrophy (FSHD by comparing the genome-wide mRNA expression profiles of 12 neuromuscular disorders. In addition, it is the only known direct transcriptional target of the double homeobox protein 4 (DUX4 of which aberrant expression has been shown to be the cause of FSHD. To test the hypothesis that up-regulation of PITX1 contributes to the skeletal muscle atrophy seen in patients with FSHD, we generated a tet-repressible muscle-specific Pitx1 transgenic mouse model in which expression of PITX1 in skeletal muscle can be controlled by oral administration of doxycycline. After PITX1 was over-expressed in the skeletal muscle for 5 weeks, the mice exhibited significant loss of body weight and muscle mass, decreased muscle strength, and reduction of muscle fiber diameters. Among the muscles examined, the tibialis anterior, gastrocnemius, quadricep, bicep, tricep and deltoid showed significant reduction of muscle mass, while the soleus, masseter and diaphragm muscles were not affected. The most prominent pathological change was the development of atrophic muscle fibers with mild necrosis and inflammatory infiltration. The affected myofibers stained heavily with NADH-TR with the strongest staining in angular-shaped atrophic fibers. Some of the atrophic fibers were also positive for embryonic myosin heavy chain using immunohistochemistry. Immunoblotting showed that the p53 was up-regulated in the muscles over-expressing PITX1. The results suggest that the up-regulation of PITX1 followed by activation of p53-dependent pathways may play a major role in the muscle atrophy developed in the mouse model.

  4. Overexpression of hepatocyte growth factor in SBMA model mice has an additive effect on combination therapy with castration

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Ying [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Adachi, Hiroaki, E-mail: hadachi-ns@umin.org [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Department of Neurology, University of Occupational and Environmental Health School of Medicine, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Katsuno, Masahisa [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Huang, Zhe [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Department of Neurology, University of Occupational and Environmental Health School of Medicine, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu 807-8555 (Japan); Jiang, Yue-Mei; Kondo, Naohide; Iida, Madoka; Tohnai, Genki; Nakatsuji, Hideaki [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Funakoshi, Hiroshi [Center for Advanced Research and Education, Asahikawa Medical University, 1-1-1- Higashinijo Midorigaoka, Asahikawa 078-8510 (Japan); Nakamura, Toshikazu [Neurogen Inc., 1-1-52-201 Nakahozumi, Ibaraki 567-0034 (Japan); Sobue, Gen, E-mail: sobueg@med.nagoya-u.ac.jp [Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Research Division of Dementia and Neurodegenerative Disease, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan)

    2015-12-25

    Spinal and bulbar muscular atrophy (SBMA) is an inherited motor neuron disease caused by the expansion of a polyglutamine (polyQ)-encoding tract within the androgen receptor (AR) gene. The pathologic features of SBMA are motor neuron loss in the spinal cord and brainstem and diffuse nuclear accumulation and nuclear inclusions of mutant AR in residual motor neurons and certain visceral organs. Hepatocyte growth factor (HGF) is a polypeptide growth factor which has neuroprotective properties. To investigate whether HGF overexpression can affect disease progression in a mouse model of SBMA, we crossed SBMA transgenic model mice expressing an AR gene with an expanded CAG repeat with mice overexpressing HGF. Here, we report that high expression of HGF induces Akt phosphorylation and modestly ameliorated motor symptoms in an SBMA transgenic mouse model treated with or without castration. These findings suggest that HGF overexpression can provide a potential therapeutic avenue as a combination therapy with disease-modifying therapies in SBMA. - Highlights: • HGF overexpression ameliorates the motor phenotypes of the SBMA mouse model. • HGF overexpression induces Akt phosphorylation in the SBMA mouse model. • This is the first report of combination therapy in a mouse model of polyQ diseases.

  5. Renoprotection From Diabetic Complications in OVE Transgenic Mice by Endothelial Cell Specific Overexpression of Metallothionein: A TEM Stereological Analysis.

    Science.gov (United States)

    Carlson, Edward C; Chhoun, Jennifer M; Grove, Bryon D; Laturnus, Donna I; Zheng, Shirong; Epstein, Paul N; Tan, Yi

    2017-03-01

    We previously demonstrated that OVE transgenic diabetic mice are susceptible to chronic complications of diabetic nephropathy (DN) including substantial oxidative damage to the renal glomerular filtration barrier (GFB). Importantly, the damage was mitigated significantly by overexpression of the powerful antioxidant, metallothionein (MT) in podocytes. To test our hypothesis that GFB damage in OVE mice is the result of endothelial oxidative insult, a new JTMT transgenic mouse was designed in which MT overexpression was targeted specifically to endothelial cells. At 60 days of age, JTMT mice were crossed with age-matched OVE diabetic mice to produce bi-transgenic OVE-JTMT diabetic progeny that carried the endothelial targeted JTMT transgene. Renal tissues from the OVE-JTMT progeny were examined by unbiased TEM stereometry for possible GFB damage and other alterations from chronic complications of DN. In 150 day-old OVE-JTMT mice, blood glucose and HbA1c were indistinguishable from age-matched OVE mice. However, endothelial-specific MT overexpression in OVE-JTMT mice mitigated several DN complications including significantly increased non-fenestrated glomerular endothelial area, and elimination of glomerular basement membrane thickening. Significant renoprotection was also observed outside of endothelial cells, including reduced podocyte effacement, and increased podocyte and total glomerular cell densities. Moreover, when compared to OVE diabetic animals, OVE-JTMT mice showed significant mitigation of nephromegaly, glomerular hypertrophy, increased mesangial cell numbers and increased total glomerular cell numbers. These results confirm the importance of oxidative stress to glomerular damage in DN, and show the central role of endothelial cell injury to the pathogenesis of chronic complications of diabetes. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:560-576, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. ErbB2 receptor over-expression improves post-traumatic peripheral nerve regeneration in adult mice.

    Science.gov (United States)

    Ronchi, Giulia; Gambarotta, Giovanna; Di Scipio, Federica; Salamone, Paolina; Sprio, Andrea E; Cavallo, Federica; Perroteau, Isabelle; Berta, Giovanni N; Geuna, Stefano

    2013-01-01

    In a transgenic mice (BALB-neuT) over-expressing ErbB2 receptor, we investigated the adult mouse median nerve in physiological and pathological conditions. Results showed that, in physiological conditions, the grip function controlled by the median nerve in BALB-neuT mice was similar to wild-type (BALB/c). Stereological assessment of ErbB2-overexpressing intact nerves revealed no difference in number and size of myelinated fibers compared to wild-type mice. By contrast, after a nerve crush injury, the motor recovery was significantly faster in BALB-neuT compared to BALB/c mice. Moreover, stereological assessment revealed a significant higher number of regenerated myelinated fibers with a thinner axon and fiber diameter and myelin thickness in BALB-neuT mice. At day-2 post-injury, the level of the mRNAs coding for all the ErbB receptors and for the transmembrane (type III) Neuregulin 1 (NRG1) isoforms significantly decreased in both BALB/c and BALB-neuT mice, as shown by quantitative real time PCR. On the other hand, the level of the mRNAs coding for soluble NRG1 isoforms (type I/II, alpha and beta) increased at the same post-traumatic time point though, intriguingly, this response was significantly higher in BALB-neuT mice with respect to BALB/c mice. Altogether, these results suggest that constitutive ErbB2 receptor over-expression does not influence the physiological development of peripheral nerves, while it improves nerve regeneration following traumatic injury, possibly through the up-regulation of soluble NRG1 isoforms.

  7. Phenotype of transgenic mice overexpressed with inducible nitric oxide synthase in the retina.

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    Guey Shuang Wu

    Full Text Available Unlike its constitutive isoforms, including neuronal and endothelial nitric oxide synthase, inducible nitric oxide synthase (iNOS along with a series of cytokines are generated in inflammatory pathologic conditions in retinal photoreceptors. In this study, we constructed transgenic mice overexpressing iNOS in the retina to evaluate the effect of sustained, intense iNOS generation in the photoreceptor damage.For construction of opsin/iNOS transgene in the CMVSport 6 expression vector, the 4.4 kb Acc65I/Xhol mouse rod opsin promoter was ligated upstream to a 4.1 kb fragment encoding the complete mouse cDNA of iNOS. From the four founders identified, two heterozygote lines and one homozygote line were established. The presence of iNOS in the retina was confirmed and the pathologic role of iNOS was assessed by detecting nitrotyrosine products and apoptosis. Commercial TUNEL kit was used to detect DNA strand breaks, a later step in a sequence of morphologic changes of apoptosis process.The insertion and translation of iNOS gene were demonstrated by an intense single 130 kDa band in Western blot and specific immunolocalization at the photoreceptors of the retina. Cellular toxicity in the retinas of transgenic animals was detected by a post-translational modification product, tyrosine-nitrated protein, the most significant one of which was nitrated cytochrome c. Following the accumulation of nitrated mitochondrial proteins and cytochrome c release, marked apoptosis was detected in the photoreceptor cell nuclei of the retina.We have generated a pathologic phenotype with sustained iNOS overexpression and, therefore, high output of nitric oxide. Under basal conditions, such overexpression of iNOS causes marked mitochondrial cytochrome c nitration and release and subsequent photoreceptor apoptosis in the retina. Therefore, the modulation of pathways leading to iNOS generation or its effective neutralization can be of significant therapeutic benefit in the

  8. ATP Synthase β-Chain Overexpression in SR-BI Knockout Mice Increases HDL Uptake and Reduces Plasma HDL Level

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    Kexiu Song

    2014-01-01

    Full Text Available HDL cholesterol is known to be inversely correlated with cardiovascular disease due to its diverse antiatherogenic functions. SR-BI mediates the selective uptake of HDL-C. SR-BI knockout diminishes but does not completely block the transport of HDL; other receptors may be involved. Ectopic ATP synthase β-chain in hepatocytes has been previously characterized as an apoA-I receptor, triggering HDL internalization. This study was undertaken to identify the overexpression of ectopic ATP synthase β-chain on DIL-HDL uptake in primary hepatocytes in vitro and on plasma HDL levels in SR-BI knockout mice. Human ATP synthase β-chain cDNA was delivered to the mouse liver by adenovirus and GFP adenovirus as control. The adenovirus-mediated overexpression of β-chain was identified at both mRNA and protein levels on mice liver and validated by its increasing of DiL-HDL uptake in primary hepatocytes. In response to hepatic overexpression of β-chain, plasma HDL-C levels and cholesterol were reduced in SR-BI knockout mice, compared with the control. The present data suggest that ATP synthase β-chain can serve as the endocytic receptor of HDL, and its overexpression can reduce plasma HDL-C.

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

    Science.gov (United States)

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

    2017-08-01

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

  10. Overexpression of IGF-I in skeletal muscle of transgenic mice does not prevent unloading-induced atrophy

    Science.gov (United States)

    Criswell, D. S.; Booth, F. W.; DeMayo, F.; Schwartz, R. J.; Gordon, S. E.; Fiorotto, M. L.

    1998-01-01

    This study examined the association between local insulin-like growth factor I (IGF-I) overexpression and atrophy in skeletal muscle. We hypothesized that endogenous skeletal muscle IGF-I mRNA expression would decrease with hindlimb unloading (HU) in mice, and that transgenic mice overexpressing human IGF-I (hIGF-I) specifically in skeletal muscle would exhibit less atrophy after HU. Male transgenic mice and nontransgenic mice from the parent strain (FVB) were divided into four groups (n = 10/group): 1) transgenic, weight-bearing (IGF-I/WB); 2) transgenic, hindlimb unloaded (IGF-I/HU); 3) nontransgenic, weight-bearing (FVB/WB); and 4) nontransgenic, hindlimb unloaded (FVB/HU). HU groups were hindlimb unloaded for 14 days. Body mass was reduced (P mice (-13%). Contrary to our hypothesis, we found that the relative abundance of mRNA for the endogenous rodent IGF-I (rIGF-I) was unaltered by HU in the gastrocnemius (GAST) muscle of wild-type FVB mice. High-level expression of hIGF-I peptide and mRNA was confirmed in the GAST and tibialis anterior (TA) muscles of the transgenic mice. Nevertheless, masses of the GAST and TA muscles were reduced (P mice. Therefore, skeletal muscle atrophy may not be associated with a reduction of endogenous rIGF-I mRNA level in 14-day HU mice. We conclude that high local expression of hIGF-I mRNA and peptide in skeletal muscle alone cannot attenuate unloading-induced atrophy of fast-twitch muscle in mice.

  11. Overexpression of IGF-I in skeletal muscle of transgenic mice does not prevent unloading-induced atrophy

    Science.gov (United States)

    Criswell, D. S.; Booth, F. W.; DeMayo, F.; Schwartz, R. J.; Gordon, S. E.; Fiorotto, M. L.

    1998-01-01

    This study examined the association between local insulin-like growth factor I (IGF-I) overexpression and atrophy in skeletal muscle. We hypothesized that endogenous skeletal muscle IGF-I mRNA expression would decrease with hindlimb unloading (HU) in mice, and that transgenic mice overexpressing human IGF-I (hIGF-I) specifically in skeletal muscle would exhibit less atrophy after HU. Male transgenic mice and nontransgenic mice from the parent strain (FVB) were divided into four groups (n = 10/group): 1) transgenic, weight-bearing (IGF-I/WB); 2) transgenic, hindlimb unloaded (IGF-I/HU); 3) nontransgenic, weight-bearing (FVB/WB); and 4) nontransgenic, hindlimb unloaded (FVB/HU). HU groups were hindlimb unloaded for 14 days. Body mass was reduced (P < 0.05) after HU in both IGF-I (-9%) and FVB mice (-13%). Contrary to our hypothesis, we found that the relative abundance of mRNA for the endogenous rodent IGF-I (rIGF-I) was unaltered by HU in the gastrocnemius (GAST) muscle of wild-type FVB mice. High-level expression of hIGF-I peptide and mRNA was confirmed in the GAST and tibialis anterior (TA) muscles of the transgenic mice. Nevertheless, masses of the GAST and TA muscles were reduced (P < 0.05) in both FVB/HU and IGF-I/HU groups compared with FVB/WB and IGF-I/WB groups, respectively, and the percent atrophy in mass of these muscles did not differ between FVB and IGF-I mice. Therefore, skeletal muscle atrophy may not be associated with a reduction of endogenous rIGF-I mRNA level in 14-day HU mice. We conclude that high local expression of hIGF-I mRNA and peptide in skeletal muscle alone cannot attenuate unloading-induced atrophy of fast-twitch muscle in mice.

  12. Disturbed α-Cell Function in Mice with β-Cell Specific Overexpression of Human Islet Amyloid Polypeptide

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    Bo Ahrén

    2008-01-01

    Full Text Available Exogenous administration of islet amyloid polypeptide (IAPP has been shown to inhibit both insulin and glucagon secretion. This study examined α-cell function in mice with β-cell specific overexpression of human IAPP (hIAPP after an oral protein gavage (75 mg whey protein/mouse. Baseline glucagon levels were higher in transgenic mice (41±4.0 pg/mL, n=6 than in wildtype animals (19±5.1 pg/mL, n=5, P=.015. In contrast, the glucagon response to protein was impaired in transgenic animals (21±2.7 pg/mL in transgenic mice versus 38±5.7 pg/mL in wildtype mice at 15 minutes; P=.027. Baseline insulin levels did not differ between the groups, while the insulin response, as the glucagon response, was impaired after protein challenge (P=.018. Glucose levels were not different between the groups and did not change significantly after protein gavage. Acetaminophen was given through gavage to the animals (2 mg/mouse to estimate gastric emptying. The plasma acetaminophen profile was similar in the two groups of mice. We conclude that disturbances in glucagon secretion exist in mice with β-cell specific overexpression of human IAPP, which are not secondary to changes in gastric emptying. The reduced glucagon response to protein challenge may reflect a direct inhibitory influence of hIAPP on glucagon secretion.

  13. Osteoblast-specific Krm2 overexpression and Lrp5 deficiency have different effects on fracture healing in mice.

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    Astrid Liedert

    Full Text Available The canonical Wnt/β-catenin pathway plays a key role in the regulation of bone remodeling in mice and humans. Two transmembrane proteins that are involved in decreasing the activity of this pathway by binding to extracellular antagonists, such as Dickkopf 1 (Dkk1, are the low-density lipoprotein receptor related protein 5 (Lrp5 and Kremen 2 (Krm2. Lrp 5 deficiency (Lrp5-/- as well as osteoblast-specific overexpression of Krm2 in mice (Col1a1-Krm2 result in severe osteoporosis occurring at young age. In this study, we analyzed the influence of Lrp5 deficiency and osteoblast-specific overexpression of Krm2 on fracture healing in mice using flexible and semi-rigid fracture fixation. We demonstrated that fracture healing was highly impaired in both mouse genotypes, but that impairment was more severe in Col1a1-Krm2 than in Lrp5-/- mice and particularly evident in mice in which the more flexible fixation was used. Bone formation was more reduced in Col1a1-Krm2 than in Lrp5-/- mice, whereas osteoclast number was similarly increased in both genotypes in comparison with wild-type mice. Using microarray analysis we identified reduced expression of genes mainly involved in osteogenesis that seemed to be responsible for the observed stronger impairment of healing in Col1a1-Krm2 mice. In line with these findings, we detected decreased expression of sphingomyelin phosphodiesterase 3 (Smpd3 and less active β-catenin in the calli of Col1a1-Krm2 mice. Since Krm2 seems to play a significant role in regulating bone formation during fracture healing, antagonizing KRM2 might be a therapeutic option to improve fracture healing under compromised conditions, such as osteoporosis.

  14. Osteoblast-specific Krm2 overexpression and Lrp5 deficiency have different effects on fracture healing in mice.

    Science.gov (United States)

    Liedert, Astrid; Röntgen, Viktoria; Schinke, Thorsten; Benisch, Peggy; Ebert, Regina; Jakob, Franz; Klein-Hitpass, Ludger; Lennerz, Jochen K; Amling, Michael; Ignatius, Anita

    2014-01-01

    The canonical Wnt/β-catenin pathway plays a key role in the regulation of bone remodeling in mice and humans. Two transmembrane proteins that are involved in decreasing the activity of this pathway by binding to extracellular antagonists, such as Dickkopf 1 (Dkk1), are the low-density lipoprotein receptor related protein 5 (Lrp5) and Kremen 2 (Krm2). Lrp 5 deficiency (Lrp5-/-) as well as osteoblast-specific overexpression of Krm2 in mice (Col1a1-Krm2) result in severe osteoporosis occurring at young age. In this study, we analyzed the influence of Lrp5 deficiency and osteoblast-specific overexpression of Krm2 on fracture healing in mice using flexible and semi-rigid fracture fixation. We demonstrated that fracture healing was highly impaired in both mouse genotypes, but that impairment was more severe in Col1a1-Krm2 than in Lrp5-/- mice and particularly evident in mice in which the more flexible fixation was used. Bone formation was more reduced in Col1a1-Krm2 than in Lrp5-/- mice, whereas osteoclast number was similarly increased in both genotypes in comparison with wild-type mice. Using microarray analysis we identified reduced expression of genes mainly involved in osteogenesis that seemed to be responsible for the observed stronger impairment of healing in Col1a1-Krm2 mice. In line with these findings, we detected decreased expression of sphingomyelin phosphodiesterase 3 (Smpd3) and less active β-catenin in the calli of Col1a1-Krm2 mice. Since Krm2 seems to play a significant role in regulating bone formation during fracture healing, antagonizing KRM2 might be a therapeutic option to improve fracture healing under compromised conditions, such as osteoporosis.

  15. Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles

    DEFF Research Database (Denmark)

    Hojman, Pernille; Brolin, Camilla; Gissel, Hanne

    2009-01-01

    patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (Pobese mice; thus the mice weighed 21.9+/-0.8 g (control, normal diet,) 21.9+/-1.4 g (EPO, normal diet), 35......Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney......-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles....

  16. Overexpression of hedgehog signaling is associated with epidermal tumor formation in vitamin D receptor-null mice.

    Science.gov (United States)

    Teichert, Arnaud E; Elalieh, Hashem; Elias, Peter M; Welsh, JoEllen; Bikle, Daniel D

    2011-11-01

    The vitamin D receptor (VDR) ligand, 1,25 dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), reduces proliferation and enhances differentiation, and thus has been investigated for a role in preventing or treating cancer. Mice deficient for the VDR display a hyperproliferative response in the hair follicle and epidermis and decreased epidermal differentiation. Unlike their wild-type littermates, when treated with 7,12 dimethylbenzanthracene (DMBA) or UVB, they develop skin tumors, including some characteristic of overexpression of the hedgehog (Hh) pathway. Both the epidermis and utricles of the VDR-null animals overexpress elements of the Hh pathway (sonic hedgehog (Shh) 2.02-fold, patched1 1.58-fold, smoothened 3.54-fold, glioma-associated oncogene homolog (Gli)1 1.17-fold, and Gli2 1.66-fold). This overexpression occurs at an age (11 weeks) at which epidermal hyperproliferation is most visible and is spatially controlled in the epidermis. DMBA- or UVB-induced tumors in the VDR-null mice also overexpress elements of this pathway. Moreover, 1,25(OH)(2)D(3) downregulates the expression of some members of the Hh pathway in an epidermal explants culture system, suggesting a direct regulation by 1,25(OH)(2)D(3). Our results suggest that increased expression of Shh in the keratinocytes of the VDR-null animal activates the Hh pathway, predisposing the skin to the development of both malignant and benign epidermal neoplasms.

  17. Over-expression of hedgehog signaling is associated with epidermal tumor formation in vitamin D receptor null mice

    OpenAIRE

    Teichert, Arnaud; Elalieh, Hashem; Elias, Peter; Welsh, JoEllen; Bikle, Daniel D.

    2011-01-01

    The vitamin D receptor (VDR) ligand, 1,25(OH)2D3, reduces proliferation and enhances differentiation and thus has been investigated for a role in preventing or treating cancer. Mice deficient for the VDR display a hyperproliferative response in the hair follicle and epidermis and decreased epidermal differentiation. Unlike their wild type littermates, when treated with 7,12 dimethylbenzanthracene (DMBA) or UVB, they develop skin tumors, including some characteristic of over-expression of the ...

  18. Reduction of experimental human fibrosarcoma lung metastasis in mice by adenovirus-mediated cystatin C overexpression in the host.

    Science.gov (United States)

    Kopitz, Charlotte; Anton, Martina; Gansbacher, Bernd; Krüger, Achim

    2005-10-01

    Tumor cell invasion and metastasis are associated with degradation of components of the extracellular matrix by different proteinases. Among those, papain-like cysteine proteases, such as cathepsin B, seem to play an important role, as they are associated with poor clinical outcome in different cancers. In this study, we tested whether cystatin C, a natural extracellular inhibitor of papain-like cysteine proteases, can inhibit metastasis when overexpressed at the tumor-host interface. Local overexpression of cystatin C in liver and lungs of CD1 nu/nu mice was achieved by gene transfer with a novel adenoviral construct, which also led to the presence of 60 ng/mL of cystatin C in the serum. Three days after gene transfer, these mice were challenged by i.v. inoculation of lacZ-tagged human fibrosarcoma cells (HT1080lacZ-K15), leading to the formation of experimental lung and liver metastases. In this model, formation of experimental metastatic foci correlated with expression of cathepsin B in lungs, whereas there was no correlation with metastasis to the liver. In mice overexpressing cystatin C, the number of lung metastases was significantly reduced by 92%, as compared with mice receiving control adenovirus. The efficacy of extravasation of HT1080lacZ-K15 cells into the liver was not affected, indicating the independence of this process from the activity of cysteine-cathepsins. The present report is the first evidence of successful reduction of metastasis by inhibition of cysteine-cathepsins by cystatin C overexpression in the host microenvironment. Furthermore, organ-specific protease expression during tumor-host cell interactions could affect the success of antiproteolytic intervention against metastasis.

  19. Transgenic Mice Over-Expressing RBP4 Have RBP4-Dependent and Light-Independent Retinal Degeneration.

    Science.gov (United States)

    Du, Mei; Phelps, Eric; Balangue, Michael J; Dockins, Aaron; Moiseyev, Gennadiy; Shin, Younghwa; Kane, Shelley; Otalora, Laura; Ma, Jian-Xing; Farjo, Rafal; Farjo, Krysten M

    2017-08-01

    Transgenic mice overexpressing serum retinol-binding protein (RBP4-Tg) develop progressive retinal degeneration, characterized by microglia activation, yet the precise mechanisms underlying retinal degeneration are unclear. Previous studies showed RBP4-Tg mice have normal ocular retinoid levels, suggesting that degeneration is independent of the retinoid visual cycle or light exposure. The present study addresses whether retinal degeneration is light-dependent and RBP4-dependent by testing the effects of dark-rearing and pharmacological lowering of serum RBP4 levels, respectively. RBP4-Tg mice reared on normal mouse chow in normal cyclic light conditions were directly compared to RBP4-Tg mice exposed to chow supplemented with the RBP4-lowering compound A1120 or dark-rearing conditions. Quantitative retinal histological analysis was conducted to assess retinal degeneration, and electroretinography (ERG) and optokinetic tracking (OKT) tests were performed to assess retinal and visual function. Ocular retinoids and bis-retinoid A2E were quantified. Dark-rearing RBP4-Tg mice effectively reduced ocular bis-retinoid A2E levels, but had no significant effect on retinal degeneration or dysfunction in RBP4-Tg mice, demonstrating that retinal degeneration is light-independent. A1120 treatment lowered serum RBP4 levels similar to wild-type mice, and prevented structural retinal degeneration. However, A1120 treatment did not prevent retinal dysfunction in RBP4-Tg mice. Moreover, RBP4-Tg mice on A1120 diet had significant worsening of OKT response and loss of cone photoreceptors compared to RBP4-Tg mice on normal chow. This may be related to the very significant reduction in retinyl ester levels in the retina of mice on A1120-supplemented diet. Retinal degeneration in RBP4-Tg mice is RBP4-dependent and light-independent.

  20. MMP-8 overexpression and persistence of neutrophils relate to stress-impaired healing and poor collagen architecture in mice

    Science.gov (United States)

    Gajendrareddy, Praveen K.; Engeland, Christopher G.; Junges, Roger; Horan, Michael P.; Rojas, Isolde G.; Marucha, Phillip T.

    2013-01-01

    Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) are critical for tissue remodeling during wound repair. Psychological stress has been found to impair wound healing in humans and animals. The objective of this study was to assess MMP and TIMP gene expression during stress-impaired healing. Female SKH-1 mice (n = 299) were divided into control and stress groups (13 h restraint/day for 3 days prior to and 5 days post-wounding). Two 3.5 mm cutaneous full-thickness wounds were placed on the dorsum of each mouse and wound measurements were performed daily. RTPCR for gene expression of MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 was performed at days 1, 3 and 5. Immunohistochemical analyses of the healed wounds were performed at days 15 and 28. As expected, wounds healed more slowly in restraint-stressed mice compared to controls. Stressed mice exhibited MMP-8 overexpression and lower TIMP-1 levels during healing, and poorer collagen organization once healed. MMP-8 overexpression may have stemmed from a higher level of neutrophils, observed in wound tissue on days 3 and 5. These findings implicate higher neutrophil numbers, MMP-8 overexpression, and TIMP-1 under-expression, as mechanisms that may compromise wound outcomes such as scarring under conditions of stress. PMID:23103444

  1. Persistent overexpression of phosphoglycerate mutase, a glycolytic enzyme, modifies energy metabolism and reduces stress resistance of heart in mice.

    Directory of Open Access Journals (Sweden)

    Junji Okuda

    Full Text Available BACKGROUND: Heart failure is associated with changes in cardiac energy metabolism. Glucose metabolism in particular is thought to be important in the pathogenesis of heart failure. We examined the effects of persistent overexpression of phosphoglycerate mutase 2 (Pgam2, a glycolytic enzyme, on cardiac energy metabolism and function. METHODS AND RESULTS: Transgenic mice constitutively overexpressing Pgam2 in a heart-specific manner were generated, and cardiac energy metabolism and function were analyzed. Cardiac function at rest was normal. The uptake of analogs of glucose or fatty acids and the phosphocreatine/βATP ratio at rest were normal. A comprehensive metabolomic analysis revealed an increase in the levels of a few metabolites immediately upstream and downstream of Pgam2 in the glycolytic pathway, whereas the levels of metabolites in the initial few steps of glycolysis and lactate remained unchanged. The levels of metabolites in the tricarboxylic acid (TCA cycle were altered. The capacity for respiration by isolated mitochondria in vitro was decreased, and that for the generation of reactive oxygen species (ROS in vitro was increased. Impaired cardiac function was observed in response to dobutamine. Mice developed systolic dysfunction upon pressure overload. CONCLUSIONS: Constitutive overexpression of Pgam2 modified energy metabolism and reduced stress resistance of heart in mice.

  2. Over-expression of X-linked inhibitor of apoptosis protein slows presbycusis in C57BL/6J mice.

    Science.gov (United States)

    Wang, Jian; Menchenton, Trevor; Yin, Shankai; Yu, Zhiping; Bance, Manohar; Morris, David P; Moore, Craig S; Korneluk, Robert G; Robertson, George S

    2010-07-01

    Apoptosis of cochlear cells plays a significant role in age-related hearing loss or presbycusis. In this study, we evaluated whether over-expression of the anti-apoptotic protein known as X-linked Inhibitor of Apoptosis Protein (XIAP) slows the development of presbycusis. We compared the age-related hearing loss between transgenic (TG) mice that over-express human XIAP tagged with 6-Myc (Myc-XIAP) on a pure C57BL/6J genetic background with wild-type (WT) littermates by measuring auditory brainstem responses. The result showed that TG mice developed hearing loss considerably more slowly than WT littermates, primarily within the high-frequency range. The average total hair cell loss was significantly less in TG mice than WT littermates. Although levels of Myc-XIAP in the ear remained constant at 2 and 14 months, there was a marked increase in the amount of endogenous XIAP from 2 to 14 months in the cochlea, but not in the brain, in both genotypes. These results suggest that XIAP over-expression reduces age-related hearing loss and hair cell death in the cochlea. Copyright 2008 Elsevier Inc. All rights reserved.

  3. The overexpression of Twinkle helicase ameliorates the progression of cardiac fibrosis and heart failure in pressure overload model in mice.

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    Atsushi Tanaka

    Full Text Available Myocardial mitochondrial DNA (mtDNA copy number decreases in heart failure. In post-myocardial infarction mice, increasing mtDNA copy number by overexpressing mitochondrial transcription factor attenuates mtDNA deficiency and ameliorates pathological remodeling thereby markedly improving survival. However, the functional significance of increased mtDNA copy number in hypertensive heart disease remains unknown. We addressed this question using transgenic mice that overexpress Twinkle helicase (Twinkle; Tg, the mtDNA helicase, and examined whether Twinkle overexpression protects the heart from left ventricular (LV remodeling and failure after pressure overload created by transverse aortic constriction (TAC. Twinkle overexpression increased mtDNA copy number by 2.2 ± 0.1-fold. Heart weight, LV diastolic volume and wall thickness were comparable between Tg and wild type littermates (WT at 28 days after TAC operation. LV end-diastolic pressure increased in WT after TAC (8.6 ± 2.8 mmHg, and this increase was attenuated in Tg (4.6 ± 2.6 mmHg. Impaired LV fractional shortening after TAC operation was also suppressed in Tg, as measured by echocardiography (WT: 16.2 ± 7.2% vs Tg: 20.7 ± 6.2%. These LV functional improvements were accompanied by a decrease in interstitial fibrosis (WT: 10.6 ± 1.1% vs Tg: 3.0 ± 0.6%. In in vitro studies, overexpressing Twinkle using an adenovirus vector in cultured cardiac fibroblasts significantly suppressed mRNA of collagen 1a, collagen 3a and connective tissue growth factor, and angiotensin II-induced transforming growth factor β1 expression. The findings suggest that Twinkle overexpression prevents LV function deterioration. In conclusion, Twinkle overexpression increases mtDNA copy number and ameliorates the progression of LV fibrosis and heart failure in a mouse pressure overload model. Increasing mtDNA copy number by Twinkle overexpression could be a novel therapeutic strategy for hypertensive heart disease.

  4. A53T-alpha-synuclein overexpression impairs dopamine signaling and striatal synaptic plasticity in old mice.

    Directory of Open Access Journals (Sweden)

    Alexander Kurz

    2010-07-01

    Full Text Available Parkinson's disease (PD, the second most frequent neurodegenerative disorder at old age, can be caused by elevated expression or the A53T missense mutation of the presynaptic protein alpha-synuclein (SNCA. PD is characterized pathologically by the preferential vulnerability of the dopaminergic nigrostriatal projection neurons.Here, we used two mouse lines overexpressing human A53T-SNCA and studied striatal dysfunction in the absence of neurodegeneration to understand early disease mechanisms. To characterize the progression, we employed young adult as well as old mice. Analysis of striatal neurotransmitter content demonstrated that dopamine (DA levels correlated directly with the level of expression of SNCA, an observation also made in SNCA-deficient (knockout, KO mice. However, the elevated DA levels in the striatum of old A53T-SNCA overexpressing mice may not be transmitted appropriately, in view of three observations. First, a transcriptional downregulation of the extraneural DA degradation enzyme catechol-ortho-methytransferase (COMT was found. Second, an upregulation of DA receptors was detected by immunoblots and autoradiography. Third, extensive transcriptome studies via microarrays and quantitative real-time RT-PCR (qPCR of altered transcript levels of the DA-inducible genes Atf2, Cb1, Freq, Homer1 and Pde7b indicated a progressive and genotype-dependent reduction in the postsynaptic DA response. As a functional consequence, long term depression (LTD was absent in corticostriatal slices from old transgenic mice.Taken together, the dysfunctional neurotransmission and impaired synaptic plasticity seen in the A53T-SNCA overexpressing mice reflect early changes within the basal ganglia prior to frank neurodegeneration. As a model of preclinical stages of PD, such insights may help to develop neuroprotective therapeutic approaches.

  5. Amyloid β Is Not the Major Factor Accounting for Impaired Adult Hippocampal Neurogenesis in Mice Overexpressing Amyloid Precursor Protein.

    Science.gov (United States)

    Pan, Hongyu; Wang, Dongpi; Zhang, Xiaoqin; Zhou, Dongming; Zhang, Heng; Qian, Qi; He, Xiao; Liu, Zhaoling; Liu, Yunjin; Zheng, Tingting; Zhang, Ling; Wang, Mingkai; Sun, Binggui

    2016-10-11

    Adult hippocampal neurogenesis was impaired in several Alzheimer's disease models overexpressing mutant human amyloid precursor protein (hAPP). However, the effects of wild-type hAPP on adult neurogenesis and whether the impaired adult hippocampal neurogenesis was caused by amyloid β (Aβ) or APP remained unclear. Here, we found that neurogenesis was impaired in the dentate gyrus (DG) of adult mice overexpressing wild-type hAPP (hAPP-I5) compared with controls. However, the adult hippocampal neurogenesis was more severely impaired in hAPP-I5 than that in hAPP-J20 mice, which express similar levels of hAPP mRNA but much higher levels of Aβ. Furthermore, reducing Aβ levels did not affect the number of doublecortin-positive cells in the DG of hAPP-J20 mice. Our results suggested that hAPP was more likely an important factor inhibiting adult neurogenesis, and Aβ was not the major factor affecting neurogenesis in the adult hippocampus of hAPP mice. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  6. p13 overexpression in pancreatic β-cells ameliorates type 2 diabetes in high-fat-fed mice.

    Science.gov (United States)

    Higashi, Shintaro; Katagi, Kazuhiko; Shintani, Norihito; Ikeda, Kazuya; Sugimoto, Yukihiko; Tsuchiya, Soken; Inoue, Naoki; Tanaka, Shota; Koumoto, Mai; Kasai, Atsushi; Nakazawa, Takanobu; Hayata-Takano, Atsuko; Hamagami, Ken-Ichi; Tomimoto, Shuhei; Yoshida, Takuya; Ohkubo, Tadayasu; Nagayasu, Kazuki; Ago, Yukio; Onaka, Yusuke; Hashimoto, Ryota; Ichikawa, Atsushi; Baba, Akemichi; Hashimoto, Hitoshi

    2015-06-12

    We examined the pancreatic function of p13 encoded by 1110001J03Rik, whose expression is decreased in pancreatic islets in high-fat-fed diabetic mice, by generating transgenic mice overexpressing p13 (p13-Tg) in pancreatic β-cells. p13-Tg mice showed normal basal glucose metabolism; however, under high-fat feeding, these animals showed augmented glucose-induced first-phase and total insulin secretion, improved glucose disposal, greater islet area and increased mitotic insulin-positive cells. In addition, high-fat diet-induced 4-hydroxynonenal immunoreactivity, a reliable marker and causative agent of lipid peroxidative stress, was significantly decreased in p13-Tg mouse islets. These results indicate that p13 is a novel pancreatic factor exerting multiple beneficial effects against type 2 diabetes. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Increased thermoregulation in cold-exposed transgenic mice overexpressing lipoprotein lipase in skeletal muscle: an avian phenotype?

    Science.gov (United States)

    Jensen, Dalan R; Knaub, Leslie A; Konhilas, John P; Leinwand, Leslie A; MacLean, Paul S; Eckel, Robert H

    2008-04-01

    LPL is an enzyme involved in the breakdown and uptake of lipoprotein triglycerides. In the present study, we examined how the transgenic (Tg) overexpression of human LPL in mouse skeletal muscle affected tolerance to cold temperatures, cold-induced thermogenesis, and fuel utilization during this response. Tg mice and their nontransgenic controls were placed in an environmental chamber and housed in metabolic chambers that monitored oxygen consumption and carbon dioxide production with calorimetry. When exposed to 4 degrees C, an attenuation in the decline in body temperature in Tg mice was accompanied by an increased metabolic rate (15%; P cold tolerance and thermogenesis in Tg mice. The more oxidative type IIa fibers were favored over the more glycolytic type IIb fibers (P cold tolerance by enhancing the capacity for fat oxidation, producing an avian-like phenotype in which skeletal muscle contributes significantly to the thermogenic response to cold temperatures.

  8. Enhanced lipid-but not carbohydrate-supported mitochondrial respiration in skeletal muscle of PGC-1α overexpressing mice.

    Science.gov (United States)

    Hoeks, Joris; Arany, Zolt; Phielix, Esther; Moonen-Kornips, Esther; Hesselink, Matthijs K C; Schrauwen, Patrick

    2012-03-01

    Skeletal muscle mitochondrial dysfunction has been linked to several disease states as well as the process of aging. A possible factor involved is the peroxisome proliferator-activated receptor (PPAR) γ co-activator 1α (PGC-1α), a major player in the regulation of skeletal muscle mitochondrial metabolism. However, it is currently unknown whether PGC-1α, besides stimulating mitochondrial proliferation, also affects the functional capacity per mitochondrion. Therefore, we here tested whether PGC-1α overexpression, besides increasing mitochondrial content, also leads to intrinsic mitochondrial adaptations. Skeletal muscle mitochondria from 10 male, muscle-specific PGC-1α overexpressing mice (PGC-1αTg) and 8 wild-type (WT) mice were isolated. Equal mitochondrial quantities were then analyzed for their oxidative capacity by high-resolution respirometry, fuelled by a carbohydrate-derived (pyruvate) and a lipid (palmitoyl-CoA plus carnitine) substrate. Additionally, mitochondria were tested for reactive oxygen species (superoxide) production and fatty acid (FA)-induced uncoupling. PGC-1αTg mitochondria were characterized by an improved intrinsic mitochondrial fat oxidative capacity as evidenced by pronounced increase in ADP-stimulated respiration (P respiration (P muscle, we show here that overexpression of PGC-1α leads to intrinsic mitochondrial adaptations that seem restricted to fat metabolism. Copyright © 2011 Wiley Periodicals, Inc.

  9. Metallothionein-I overexpression alters brain inflammation and stimulates brain repair in transgenic mice with astrocyte-targeted interleukin-6 expression

    DEFF Research Database (Denmark)

    Penkowa, Milena; Camats, Jordi; Giralt, Mercedes

    2003-01-01

    to a higher extent in the GFAP-IL-6 mice, suggesting that they could be related to the neuroprotection afforded by the transgenic expression of IL-6. To examine this possibility, we have crossed GFAP-IL-6 mice with transgenic mice overexpressing MT-I (TgMT), producing double transgenic GFAP-IL-6 TgMT mice....... The results obtained after cryolesion in GFAP-IL-6 TgMT mice, as well as in TgMT mice, consistently supported the idea that the increased MT-I+II levels observed in GFAP-IL-6 mice are a fundamental and important mechanism for coping with brain damage. Accordingly, MT-I overexpression regulated...

  10. TRIP-Br2 promotes oncogenesis in nude mice and is frequently overexpressed in multiple human tumors.

    Science.gov (United States)

    Cheong, Jit Kong; Gunaratnam, Lakshman; Zang, Zhi Jiang; Yang, Christopher M; Sun, Xiaoming; Nasr, Susan L; Sim, Khe Guan; Peh, Bee Keow; Rashid, Suhaimi Bin Abdul; Bonventre, Joseph V; Salto-Tellez, Manuel; Hsu, Stephen I

    2009-01-20

    Members of the TRIP-Br/SERTAD family of mammalian transcriptional coregulators have recently been implicated in E2F-mediated cell cycle progression and tumorigenesis. We, herein, focus on the detailed functional characterization of the least understood member of the TRIP-Br/SERTAD protein family, TRIP-Br2 (SERTAD2). Oncogenic potential of TRIP-Br2 was demonstrated by (1) inoculation of NIH3T3 fibroblasts, which were engineered to stably overexpress ectopic TRIP-Br2, into athymic nude mice for tumor induction and (2) comprehensive immunohistochemical high-throughput screening of TRIP-Br2 protein expression in multiple human tumor cell lines and human tumor tissue microarrays (TMAs). Clinicopathologic analysis was conducted to assess the potential of TRIP-Br2 as a novel prognostic marker of human cancer. RNA interference of TRIP-Br2 expression in HCT-116 colorectal carcinoma cells was performed to determine the potential of TRIP-Br2 as a novel chemotherapeutic drug target. Overexpression of TRIP-Br2 is sufficient to transform murine fibroblasts and promotes tumorigenesis in nude mice. The transformed phenotype is characterized by deregulation of the E2F/DP-transcriptional pathway through upregulation of the key E2F-responsive genes CYCLIN E, CYCLIN A2, CDC6 and DHFR. TRIP-Br2 is frequently overexpressed in both cancer cell lines and multiple human tumors. Clinicopathologic correlation indicates that overexpression of TRIP-Br2 in hepatocellular carcinoma is associated with a worse clinical outcome by Kaplan-Meier survival analysis. Small interfering RNA-mediated (siRNA) knockdown of TRIP-Br2 was sufficient to inhibit cell-autonomous growth of HCT-116 cells in vitro. This study identifies TRIP-Br2 as a bona-fide protooncogene and supports the potential for TRIP-Br2 as a novel prognostic marker and a chemotherapeutic drug target in human cancer.

  11. Calpastatin overexpression in the skeletal muscle of mice prevents clenbuterol-induced muscle hypertrophy and phenotypic shift.

    Science.gov (United States)

    Douillard, Aymeric; Galbes, Olivier; Begue, Gwenaelle; Rossano, Bernadette; Levin, John; Vernus, Barbara; Bonnieu, Anne; Candau, Robin; Py, Guillaume

    2012-04-01

    Accumulating evidence suggests that the calpain/calpastatin system is involved in skeletal muscle remodelling induced by β(2) -adrenoceptor agonist treatment. In addition to other pathways, the Akt/mammalian target of rapamycin (mTOR) pathway, controlling protein synthesis, and the calcium/calmodulin-dependent protein kinase 2 (CamK2) and AMP-activated protein kinase (AMPK) pathways, recently identified as calpain substrates, could be relevant in β(2) -adrenoceptor agonist-induced skeletal muscle remodelling. In the present study we investigated muscle hypertrophy and phenotypic shifts, as well as the molecular response of components of the Akt/mTOR pathway (i.e. Akt, eukaryotic initiation factor 4E-binding protein 1 (4E-BP1), ribosomal protein S6 (rpS6), CamK2 and AMPK), in response to calpastatin overexpression in the skeletal muscle of mice treated with 1 mg/kg per day clenbuterol for 21 days. Using gene electrotransfer of a calpastatin expression vector into the tibialis anterior of adult mice, we found that calpastatin overexpression attenuates muscle hypertrophy and phenotypic shifts induced by clenbuterol treatment. At the molecular level, calpastatin overexpression markedly decreased calpain activity, but was ineffective in altering the phosphorylation of Akt, 4E-BP1 and rpS6. In contrast, calpastatin overexpression increased the protein expression of both total AMPK and total CamK2. In conclusion, the results support the contention that the calpain/calpastatin system plays a crucial role in skeletal muscle hypertrophy and phenotypic shifts under chronic clenbuterol treatment, with AMPK and CamK2 probably playing a minor role. Moreover, the calpastatin-induced inhibition of hypertrophy under clenbuterol treatment was not related to a decreased mTOR-dependent initiation of protein translation. © 2012 The Authors Clinical and Experimental Pharmacology and Physiology © 2012 Blackwell Publishing Asia Pty Ltd.

  12. Cognition, learning behaviour and hippocampal synaptic plasticity are not disrupted in mice over-expressing the cholesterol transporter ABCG1

    Directory of Open Access Journals (Sweden)

    Eadie Brennan D

    2009-02-01

    Full Text Available Abstract Background Cognitive deficits are a hallmark feature of both Down Syndrome (DS and Alzheimer's Disease (AD. Extra copies of the genes on chromosome 21 may also play an important role in the accelerated onset of AD in DS individuals. Growing evidence suggests an important function for cholesterol in the pathogenesis of AD, particularly in APP metabolism and production of Aβ peptides. The ATP-Binding Cassette-G1 (ABCG1 transporter is located on chromosome 21, and participates in the maintenance of tissue cholesterol homeostasis. Results To assess the role of ABCG1 in DS-related cognition, we evaluated the cognitive performance of mice selectively over-expressing the ABCG1 gene from its endogenous regulatory signals. Both wild-type and ABCG1 transgenic mice performed equivalently on several behavioral tests, including measures of anxiety, as well as on reference and working memory tasks. No deficits in hippocampal CA1 synaptic plasticity as determined with electrophysiological studies were apparent in mice over-expressing ABCG1. Conclusion These findings indicate that although ABCG1 may play a role in maintaining cellular or tissue cholesterol homeostasis, it is unlikely that excess ABCG1 expression contributes to the cognitive deficits in DS individuals.

  13. PSRC1 overexpression attenuates atherosclerosis progression in apoE-/-mice by modulating cholesterol transportation and inflammation.

    Science.gov (United States)

    Guo, Kai; Hu, Lu; Xi, Dan; Zhao, Jinzhen; Liu, Jichen; Luo, Tiantian; Ma, Yusheng; Lai, Wenyan; Guo, Zhigang

    2018-03-01

    Human genome-wide association studies (GWAS) have found that proline/serine-rich coiled-coil 1 (PSRC1) encodes a protein that is associated with serum lipid levels and coronary artery disease. In addition, our previous study showed that the cholesterol efflux capacity is decreased in macrophages following a treatment silencing Psrc1, indicating that PSRC1 has anti-atherosclerotic effects. However, the role of PSRC1 in the development of atherosclerosis is unknown. This study aims to explore the effect of PSRC1 on atherosclerosis and its underlying mechanisms. A recombinant adenovirus expressing Psrc1 (Ad-PSRC1) was constructed and transfected in RAW264.7 cells as well as injected intravenously into apoE -/- mice. The in vitro study showed that PSRC1 overexpression reduced the cellular cholesterol content, increased the cholesterol efflux capacity and inhibited foam cell formation by upregulating the expression of peroxisome proliferator-activated receptor γ (PPAR-γ) and liver X receptor α (LXR-α), which are key cholesterol transportation-related proteins. Infecting apoE -/- mice with Ad-PSRC1 inhibited the development of atherosclerotic lesions and enhanced atherosclerotic plaque stability. Consistent with these results, PSRC1 overexpression in apoE -/- mice decreased the plasma levels of TC, TG, LDL-C, TNF-α, IL-1β and IL-6, increased the plasma HDL-C levels and improved HDL function. Similarly, the PPAR-γ and LXR-α expression levels were upregulated in the liver and in peritoneal macrophages of PSRC1-overexpressing apoE -/- mice. Finally, the liver and peritoneal macrophages of apoE -/- mice displayed elevated expression of β-catenin, which is a direct downstream gene of PSRC1 and an upstream gene of PPAR-γ and LXR-α, but decreased activity of nuclear transcription factor (NF-κB), which acts as a key gene in the regulation of inflammation. PSRC1 protects against the development of atherosclerosis and enhances the stability of plaques by modulating

  14. Hyperlipidemia and cutaneous abnormalities in transgenic mice overexpressing human apolipoprotein C1

    NARCIS (Netherlands)

    Jong, M.C.; Gijbels, M.J.J.; Dahlmans, V.E.H.; Gorp, P.J.J. van; Koopman, S.-J.; Ponec, M.; Hofker, M.H.; Havekes, L.M.

    1998-01-01

    Transgenic mice were generated with different levels of human apolipoprotein C1 (APOC1) expression in liver and skin. At 2 mo of age, serum levels of cholesterol, triglycerides (TG), and FFA were strongly elevated in APOC1 transgenic mice compared with wild-type mice. These elevated levels of serum

  15. TREM2 Overexpression has No Improvement on Neuropathology and Cognitive Impairment in Aging APPswe/PS1dE9 Mice.

    Science.gov (United States)

    Jiang, Teng; Wan, Yu; Zhang, Ying-Dong; Zhou, Jun-Shan; Gao, Qing; Zhu, Xi-Chen; Shi, Jian-Quan; Lu, Huan; Tan, Lan; Yu, Jin-Tai

    2017-03-01

    Previously, we showed that overexpression of triggering receptor expressed on myeloid cells 2 (TREM2), a microglia-specific immune receptor, in the brain of a middle-aged (7 months old) APPswe/PS1dE9 mice could ameliorate Alzheimer's disease (AD)-related neuropathology by enhancement of microglial amyloid-β (Aβ) phagocytosis. Since AD is an age-related neurodegenerative disorder, it is critical to assess the efficacy of TREM2 overexpression in aging animals with an advanced disease stage. In vivo, we employed a lentiviral strategy to overexpress TREM2 in the brain of aging (18 months old) APPswe/PS1dE9 mice, and observed its efficacy on AD-related neuropathology and cognitive functions. Afterwards, we directly isolated microglia from middle-aged and aging APPswe/PS1dE9 mice and determined effects of TREM2 overexpression on microglial Aβ phagocytosis and Aβ-binding receptors expression in vitro. In aging APPswe/PS1dE9 mice, TREM2 overexpression has no beneficial effect on AD-related neuropathology and spatial cognitive functions. Of note, in vitro experiments showed a significant reduction of Aβ phagocytosis in microglia from aging APPswe/PS1dE9 mice, possibly attributing to the declined expression of Aβ-binding receptors. Meanwhile, this phagocytic deficit in microglia from aging APPswe/PS1dE9 mice cannot be rescued by TREM2 overexpression. Taken together, our study shows that TREM2 overexpression fails to provide neuroprotection in aging APPswe/PS1dE9 mice, possibly attributing to deficits in microglial Aβ phagocytosis at the late-stage of disease progression. These findings indicate that TREM2-mediated protection in AD is at least partially dependent on the reservation of microglial phagocytic functions, emphasizing the importance of early therapeutic interventions for this devastating disease.

  16. Transgenic overexpression of γ-cytoplasmic actin protects against eccentric contraction-induced force loss in mdx mice

    Science.gov (United States)

    2011-01-01

    Background γ-cytoplasmic (γ-cyto) actin levels are elevated in dystrophin-deficient mdx mouse skeletal muscle. The purpose of this study was to determine whether further elevation of γ-cyto actin levels improve or exacerbate the dystrophic phenotype of mdx mice. Methods We transgenically overexpressed γ-cyto actin, specifically in skeletal muscle of mdx mice (mdx-TG), and compared skeletal muscle pathology and force-generating capacity between mdx and mdx-TG mice at different ages. We investigated the mechanism by which γ-cyto actin provides protection from force loss by studying the role of calcium channels and stretch-activated channels in isolated skeletal muscles and muscle fibers. Analysis of variance or independent t-tests were used to detect statistical differences between groups. Results Levels of γ-cyto actin in mdx-TG skeletal muscle were elevated 200-fold compared to mdx skeletal muscle and incorporated into thin filaments. Overexpression of γ-cyto actin had little effect on most parameters of mdx muscle pathology. However, γ-cyto actin provided statistically significant protection against force loss during eccentric contractions. Store-operated calcium entry across the sarcolemma did not differ between mdx fibers compared to wild-type fibers. Additionally, the omission of extracellular calcium or the addition of streptomycin to block stretch-activated channels did not improve the force-generating capacity of isolated extensor digitorum longus muscles from mdx mice during eccentric contractions. Conclusions The data presented in this study indicate that upregulation of γ-cyto actin in dystrophic skeletal muscle can attenuate force loss during eccentric contractions and that the mechanism is independent of activation of stretch-activated channels and the accumulation of extracellular calcium. PMID:21995957

  17. Overexpression of thioredoxin in islets transduced by a lentiviral vector prolongs graft survival in autoimmune diabetic NOD mice

    Directory of Open Access Journals (Sweden)

    Sytwu Huey-Kang

    2009-08-01

    Full Text Available Abstract Pancreatic islet transplantation is considered an appropriate treatment to achieve insulin independence in type I diabetic patients. However, islet isolation and transplantation-induced oxidative stress and autoimmune-mediated destruction are still the major obstacles to the long-term survival of graft islets in this potential therapy. To protect islet grafts from inflammatory damage and prolong their survival, we transduced islets with an antioxidative gene thioredoxin (TRX using a lentiviral vector before transplantation. We hypothesized that the overexpression of TRX in islets would prolong islet graft survival when transplanted into diabetic non-obese diabetic (NOD mice. Methods Islets were isolated from NOD mice and transduced with lentivirus carrying TRX (Lt-TRX or enhanced green fluorescence protein (Lt-eGFP, respectively. Transduced islets were transplanted under the left kidney capsule of female diabetic NOD mice, and blood glucose concentration was monitored daily after transplantation. The histology of the islet graft was assessed at the end of the study. The protective effect of TRX on islets was investigated. Results The lentiviral vector effectively transduced islets without altering the glucose-stimulating insulin-secretory function of islets. Overexpression of TRX in islets reduced hydrogen peroxide-induced cytotoxicity in vitro. After transplantation into diabetic NOD mice, euglycemia was maintained for significantly longer in Lt-TRX-transduced islets than in Lt-eGFP-transduced islets; the mean graft survival was 18 vs. 6.5 days (n = 9 and 10, respectively, p Conclusion We successfully transduced the TRX gene into islets and demonstrated that these genetically modified grafts are resistant to inflammatory insult and survived longer in diabetic recipients. Our results further support the concept that the reactive oxygen species (ROS scavenger and antiapoptotic functions of TRX are critical to islet survival after

  18. Transgenic overexpression of γ-cytoplasmic actin protects against eccentric contraction-induced force loss in mdx mice

    Directory of Open Access Journals (Sweden)

    Baltgalvis Kristen A

    2011-10-01

    Full Text Available Abstract Background γ-cytoplasmic (γ-cyto actin levels are elevated in dystrophin-deficient mdx mouse skeletal muscle. The purpose of this study was to determine whether further elevation of γ-cyto actin levels improve or exacerbate the dystrophic phenotype of mdx mice. Methods We transgenically overexpressed γ-cyto actin, specifically in skeletal muscle of mdx mice (mdx-TG, and compared skeletal muscle pathology and force-generating capacity between mdx and mdx-TG mice at different ages. We investigated the mechanism by which γ-cyto actin provides protection from force loss by studying the role of calcium channels and stretch-activated channels in isolated skeletal muscles and muscle fibers. Analysis of variance or independent t-tests were used to detect statistical differences between groups. Results Levels of γ-cyto actin in mdx-TG skeletal muscle were elevated 200-fold compared to mdx skeletal muscle and incorporated into thin filaments. Overexpression of γ-cyto actin had little effect on most parameters of mdx muscle pathology. However, γ-cyto actin provided statistically significant protection against force loss during eccentric contractions. Store-operated calcium entry across the sarcolemma did not differ between mdx fibers compared to wild-type fibers. Additionally, the omission of extracellular calcium or the addition of streptomycin to block stretch-activated channels did not improve the force-generating capacity of isolated extensor digitorum longus muscles from mdx mice during eccentric contractions. Conclusions The data presented in this study indicate that upregulation of γ-cyto actin in dystrophic skeletal muscle can attenuate force loss during eccentric contractions and that the mechanism is independent of activation of stretch-activated channels and the accumulation of extracellular calcium.

  19. Enhanced Stress Response in 5-HT1AR Overexpressing Mice: Altered HPA Function and Hippocampal Long-Term Potentiation.

    Science.gov (United States)

    Pilar-Cuéllar, Fuencisla; Vidal, Rebeca; Díaz, Álvaro; Garro-Martínez, Emilio; Linge, Raquel; Castro, Elena; Haberzettl, Robert; Fink, Heidrun; Bert, Bettina; Brosda, Jan; Romero, Beatriz; Crespo-Facorro, Benedicto; Pazos, Ángel

    2017-11-15

    Postsynaptic 5-HT 1A receptors (5-HT 1A R) play an important role in anxiety and stress, although their contribution is still controversial. Previous studies report that mice overexpressing postsynaptic 5-HT 1A Rs show no changes in basal anxiety, though the influence of stress conditions has not been addressed yet. In this study, we used this animal model to evaluate the role of 5-HT 1A Rs in anxiety response after pre-exposure to an acute stressor. Under basal conditions, 5-HT 1A R overexpressing animals presented high corticosterone levels and a lower mineralocorticoid/glucocorticoid receptor ratio. After pre-exposure to a single stressor, they showed a high anxiety-like response, associated with a blunted increase in corticosterone levels and higher c-Fos activation in the prefrontal cortex. Moreover, these mice also presented a lack of downregulation of hippocampal long-term potentiation after stress exposure. Therefore, higher postsynaptic 5-HT 1A R activation might predispose to a high anxious phenotype and an impaired stress coping behavior.

  20. Persistent Coxiella burnetii infection in mice overexpressing IL-10: an efficient model for chronic Q fever pathogenesis.

    Directory of Open Access Journals (Sweden)

    Soraya Meghari

    2008-02-01

    Full Text Available Interleukin (IL-10 increases host susceptibility to microorganisms and is involved in intracellular persistence of bacterial pathogens. IL-10 is associated with chronic Q fever, an infectious disease due to the intracellular bacterium Coxiella burnetii. Nevertheless, accurate animal models of chronic C. burnetii infection are lacking. Transgenic mice constitutively expressing IL-10 in macrophages were infected with C. burnetti by intraperitoneal and intratracheal routes and infection was analyzed through real-time PCR and antibody production. Transgenic mice exhibited sustained tissue infection and strong antibody response in contrast to wild-type mice; thus, bacterial persistence was IL-10-dependent as in chronic Q fever. The number of granulomas was low in spleen and liver of transgenic mice infected through the intraperitoneal route, as in patients with chronic Q fever. Macrophages from transgenic mice were unable to kill C. burnetii. C. burnetii-stimulated macrophages were characterized by non-microbicidal transcriptional program consisting of increased expression of arginase-1, mannose receptor, and Ym1/2, in contrast to wild-type macrophages in which expression of inducible NO synthase and inflammatory cytokines was increased. In vivo results emphasized macrophage data. In spleen and liver of transgenic mice infected with C. burnetii by the intraperitoneal route, the expression of arginase-1 was increased while microbicidal pathway consisting of IL-12p40, IL-23p19, and inducible NO synthase was depressed. The overexpression of IL-10 in macrophages prevents anti-infectious competence of host, including the ability to mount granulomatous response and microbicidal pathway in tissues. To our knowledge, this is the first efficient model for chronic Q fever pathogenesis.

  1. Overexpression of Nrf2 protects against microcystin-induced hepatotoxicity in mice.

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    Yuan-Fu Lu

    Full Text Available Oxidative stress and glutathione (GSH depletion are implicated in mycocystin hepatotoxicity. To investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2 in microcystin-induced liver injury, Nrf2-null, wild-type, and Keap1-hepatocyte knockout (Keap1-HKO mice were treated with microcystin (50 μg/kg, i.p.. Blood and liver samples were collected 8 h thereafter. Microcystin increased serum alanine aminotransferase and aspartate aminotransferase activities, and caused extensive inflammation and necrosis in Nrf2-null and wild-type mice, but not in Keap1-HKO mice. Oxidative stress and inflammation are implicated in microcystin-induced hepatotoxicity, as evidenced by increased lipid peroxidation and increased expression of pro-inflammatory genes, such as neutrophil-specific chemokines mKC and MIP-2, and pro-inflammatory cytokines IL-1β and IL-6. The increased expression of these pro-inflammatory genes was attenuated in Keap1-HKO mice. Nrf2 and Nqo1 mRNA and protein were higher in Keap1-HKO mice at constitutive levels and after microcystin. To further investigate the mechanism of the protection, hepatic GSH and the mRNA of GSH-related enzymes were determined. Microcystin markedly depleted liver GSH by 60-70% in Nrf2 and WT mice but only 35% in Keap1-HKO mice. The mRNAs of GSH conjugation and peroxide reduction enzymes, such as Gstα1, Gstα4, Gstμ, and Gpx2 were higher in livers of Keap1-HKO mice, together with higher expression of the rate-limiting enzyme for GSH synthesis (Gclc. Organic anion transport polypeptides were increased by microcystin with the most increase in Keap1-HKO mice. In conclusion, this study demonstrates that higher basal levels of Nrf2 and GSH-related genes in Keap1-HKO mice prevented microcystin-induced oxidative stress and liver injury.

  2. Catalase overexpression does not impair extensor digitorum longus muscle function in normal mice.

    Science.gov (United States)

    Liu, Mingju; Yue, Yongping; Li, Dejia; Duan, Dongsheng

    2007-12-01

    Catalase is a major antioxidant enzyme. Increasing catalase expression represents a promising avenue to improve muscle function in certain physiological conditions and in some muscle diseases. We hypothesized that catalase overexpression should not impair normal muscle contraction. We delivered a hemagglutinin (HA)-tagged human catalase gene to normal mouse muscle by an adeno-associated viral vector (AAV). Western blot and immunostaining revealed efficient expression of HA-tagged catalase. Enzymatic assay demonstrated an approximately threefold increase in catalase activity in AAV-infected muscles. Catalase overexpression impaired neither twitch nor tetanic tension in the extensor digitorum longus (EDL) muscle. Furthermore, EDL fatigue response was not altered. Taken together, we have developed a novel AAV vector to enhance catalase expression. Lack of apparent toxicity in normal muscle strongly supports further exploration of this vector to reduce oxidative stress-induced muscle damage.

  3. No dramatic age-related loss of hair cells and spiral ganglion neurons in Bcl-2 over-expression mice or Bax null mice

    Directory of Open Access Journals (Sweden)

    Ohlemiller Kevin K

    2010-07-01

    Full Text Available Abstract Age-related decline of neuronal function is associated with age-related structural changes. In the central nervous system, age-related decline of cognitive performance is thought to be caused by synaptic loss instead of neuronal loss. However, in the cochlea, age-related loss of hair cells and spiral ganglion neurons (SGNs is consistently observed in a variety of species, including humans. Since age-related loss of these cells is a major contributing factor to presbycusis, it is important to study possible molecular mechanisms underlying this age-related cell death. Previous studies suggested that apoptotic pathways were involved in age-related loss of hair cells and SGNs. In the present study, we examined the role of Bcl-2 gene in age-related hearing loss. In one transgenic mouse line over-expressing human Bcl-2, there were no significant differences between transgenic mice and wild type littermate controls in their hearing thresholds during aging. Histological analysis of the hair cells and SGNs showed no significant conservation of these cells in transgenic animals compared to the wild type controls during aging. These data suggest that Bcl-2 overexpression has no significant effect on age-related loss of hair cells and SGNs. We also found no delay of age-related hearing loss in mice lacking Bax gene. These findings suggest that age-related hearing loss is not through an apoptotic pathway involving key members of Bcl-2 family.

  4. TRIP-Br2 promotes oncogenesis in nude mice and is frequently overexpressed in multiple human tumors

    Directory of Open Access Journals (Sweden)

    Peh Bee

    2009-01-01

    Full Text Available Abstract Background Members of the TRIP-Br/SERTAD family of mammalian transcriptional coregulators have recently been implicated in E2F-mediated cell cycle progression and tumorigenesis. We, herein, focus on the detailed functional characterization of the least understood member of the TRIP-Br/SERTAD protein family, TRIP-Br2 (SERTAD2. Methods Oncogenic potential of TRIP-Br2 was demonstrated by (1 inoculation of NIH3T3 fibroblasts, which were engineered to stably overexpress ectopic TRIP-Br2, into athymic nude mice for tumor induction and (2 comprehensive immunohistochemical high-throughput screening of TRIP-Br2 protein expression in multiple human tumor cell lines and human tumor tissue microarrays (TMAs. Clinicopathologic analysis was conducted to assess the potential of TRIP-Br2 as a novel prognostic marker of human cancer. RNA interference of TRIP-Br2 expression in HCT-116 colorectal carcinoma cells was performed to determine the potential of TRIP-Br2 as a novel chemotherapeutic drug target. Results Overexpression of TRIP-Br2 is sufficient to transform murine fibroblasts and promotes tumorigenesis in nude mice. The transformed phenotype is characterized by deregulation of the E2F/DP-transcriptional pathway through upregulation of the key E2F-responsive genes CYCLIN E, CYCLIN A2, CDC6 and DHFR. TRIP-Br2 is frequently overexpressed in both cancer cell lines and multiple human tumors. Clinicopathologic correlation indicates that overexpression of TRIP-Br2 in hepatocellular carcinoma is associated with a worse clinical outcome by Kaplan-Meier survival analysis. Small interfering RNA-mediated (siRNA knockdown of TRIP-Br2 was sufficient to inhibit cell-autonomous growth of HCT-116 cells in vitro. Conclusion This study identifies TRIP-Br2 as a bona-fide protooncogene and supports the potential for TRIP-Br2 as a novel prognostic marker and a chemotherapeutic drug target in human cancer.

  5. Midkine is overexpressed in acute pancreatitis and promotes the pancreatic recovery in L-arginine-induced acute pancreatitis in mice.

    Science.gov (United States)

    Cheng, Li; Qiao, Zhenguo; Xu, Chunfang; Shen, Jiaqing

    2017-06-01

    Midkine (MK) is involved in the pathogenesis of numerous malignancies, but the expression and effect of MK in acute pancreatitis (AP) have not been well studied and documented. In this study, the expression of MK was assayed in mice with L-arginine-induced AP. A recombinant human MK (rhMK) was introduced in this study to test the effect of MK on the L-arginine-induced AP. Serum amylase and lipase were assayed. Pancreas tissue samples were also collected for the evaluation of histological injury. Western blot and immunochemical staining of α-amylase and proliferating cell nuclear antigen were applied for the study of acinar regeneration in the pancreas. The elevation of MK expression was found in mice with AP induced by L-arginine. After rhMK administration, rhMK did not affect the severity of acute pancreatic injury in acute phase in L-arginine-induced pancreatitis in mice, in accordance with changes of serum amylase and lipase and the histological evaluation. But during the recovery phase, the area of remaining acinar cells was increased and the fibrosis was reduced in rhMK-treated mice. Furthermore, the expression of proliferating cell nuclear antigen and α-amylase was also upregulated after rhMK treatment. Midkine is over-expressed during AP in the animal model. Recombinant MK could promote the recovery of L-arginine-induced pancreatitis in mice. Therefore, MK may be involved in the regeneration of acinar cells in AP, and rhMK may be a possible therapeutic intervention for the repairment of AP. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  6. Novel Transgenic Mice for Inducible Gene Overexpression in Pancreatic Cells Define Glucocorticoid Receptor-Mediated Regulations of Beta Cells

    Science.gov (United States)

    Massouridès, Emmanuelle; Singh-Estivalet, Amrit; Valtat, Bérengère; Dorchene, Delphine; Jaisser, Frédéric; Bréant, Bernadette; Tronche, Francois

    2012-01-01

    Conditional gene deletion in specific cell populations has helped the understanding of pancreas development. Using this approach, we have shown that deleting the glucocorticoid receptor (GR) gene in pancreatic precursor cells leads to a doubled beta-cell mass. Here, we provide genetic tools that permit a temporally and spatially controlled expression of target genes in pancreatic cells using the Tetracycline inducible system. To efficiently target the Tetracycline transactivator (tTA) in specific cell populations, we generated Bacterial Artificial Chromosomes (BAC) transgenic mice expressing the improved Tetracycline transactivator (itTA) either in pancreatic progenitor cells expressing the transcription factor Pdx1 (BAC-Pdx1-itTA), or in beta cells expressing the insulin1 gene (BAC-Ins1-itTA). In the two transgenic models, itTA-mediated activation of reporter genes was efficient and subject to regulation by Doxycycline (Dox). The analysis of a tetracycline-regulated LacZ reporter gene shows that in BAC-Pdx1-itTA mice, itTA is expressed from embryonic (E) day 11.5 in all pancreatic precursor cells. In the adult pancreas, itTA is active in mature beta, delta cells and in few acinar cells. In BAC-Ins1-itTA mice tTA is active from E13.5 and is restricted to beta cells in fetal and adult pancreas. In both lines, tTA activity was suppressed by Dox treatment and re-induced after Dox removal. Using these transgenic lines, we overexpressed the GR in selective pancreatic cell populations and found that overexpression in precursor cells altered adult beta-cell fraction but not glucose tolerance. In contrast, GR overexpression in mature beta cells did not alter beta-cell fraction but impaired glucose tolerance with insufficient insulin secretion. In conclusion, these new itTA mouse models will allow fine-tuning of gene expression to investigate gene function in pancreatic biology and help us understand how glucocorticoid signaling affects on the long-term distinct aspects of

  7. Overexpression of TSC-22 (transforming growth factor-β-stimulated clone-22) causes marked obesity, splenic abnormality and B cell lymphoma in transgenic mice

    Science.gov (United States)

    Miwa, Yoshihiro; Horiuchi, Hideki; Furihata, Tadashi; Tachibana, Masatsugu; Fujimori, Takahiro

    2016-01-01

    In this study, we generated transgenic (Tg) mice, which overexpressed transforming growth factor (TGF)-β stimulated clone-22 (TSC-22), and investigate the functional role of TSC-22 on their development and pathogenesis. We obtained 13 Tg-founders (two mice from C57BL6/J and 11 mice from BDF1). Three of 13 Tg-founders were sterile, and the remaining Tg-founders also could generate only a limited number of the F1 generation. We obtained 32 Tg-F1 mice. Most of the Tg-mice showed marked obesity. Histopathological examination could be performed on 31 Tg-mice; seventeen mice died by some disease in their entire life and 14 mice were killed for examination. Most of the Tg-mice examined showed splenic abnormality, in which marked increase of the megakaryocytes, unclearness of the margin of the red pulp and the white pulp, and the enlargement of the white pulp was observed. B cell lymphoma was developed in 10 (71%) of 14 disease-died F1 mice. These results indicate that constitutive over-expression of TSC-22 might disturb the normal embryogenesis and the normal lipid metabolism, and induce the oncogenic differentiation of hematopoietic cells. PMID:26872059

  8. Overexpression of TSC-22 (transforming growth factor- β-stimulated clone-22) causes marked obesity, splenic abnormality and B cell lymphoma in transgenic mice.

    Science.gov (United States)

    Uchida, Daisuke; Kawamata, Hitoshi; Omotehara, Fumie; Miwa, Yoshihiro; Horiuchi, Hideki; Furihata, Tadashi; Tachibana, Masatsugu; Fujimori, Takahiro

    2016-03-22

    In this study, we generated transgenic (Tg) mice, which overexpressed transforming growth factor (TGF)-β stimulated clone-22 (TSC-22), and investigate the functional role of TSC-22 on their development and pathogenesis. We obtained 13 Tg-founders (two mice from C57BL6/J and 11 mice from BDF1). Three of 13 Tg-founders were sterile, and the remaining Tg-founders also could generate only a limited number of the F1 generation. We obtained 32 Tg-F1 mice. Most of the Tg-mice showed marked obesity. Histopathological examination could be performed on 31 Tg-mice; seventeen mice died by some disease in their entire life and 14 mice were killed for examination. Most of the Tg-mice examined showed splenic abnormality, in which marked increase of the megakaryocytes, unclearness of the margin of the red pulp and the white pulp, and the enlargement of the white pulp was observed. B cell lymphoma was developed in 10 (71%) of 14 disease-died F1 mice. These results indicate that constitutive over-expression of TSC-22 might disturb the normal embryogenesis and the normal lipid metabolism, and induce the oncogenic differentiation of hematopoietic cells.

  9. Overexpression of protein kinase STK25 in mice exacerbates ectopic lipid accumulation, mitochondrial dysfunction and insulin resistance in skeletal muscle

    DEFF Research Database (Denmark)

    Chursa, Urszula; Nuñez-Durán, Esther; Cansby, Emmelie

    2017-01-01

    and insulin sensitivity were assessed by treadmill running and euglycaemic-hyperinsulinaemic clamp, respectively, and muscle lipid metabolism was analysed by ex vivo assays in Stk25 transgenic and wild-type mice fed a high-fat diet. Lipid accumulation and mitochondrial function were also studied in rodent...... of liver steatosis, hepatic lipid metabolism and whole body glucose and insulin homeostasis. Here, we assessed the role of STK25 in control of ectopic fat storage and insulin responsiveness in skeletal muscle. METHODS: Skeletal muscle morphology was studied by histological examination, exercise performance...... and impaired mitochondrial function in rodent myoblasts overexpressing STK25, demonstrating an autonomous action for STK25 within cells. Global phosphoproteomic analysis revealed alterations in the total abundance and phosphorylation status of different target proteins located predominantly to mitochondria...

  10. Intranasal NAP (davunetide) decreases tau hyperphosphorylation and moderately improves behavioral deficits in mice overexpressing α-synuclein.

    Science.gov (United States)

    Magen, Iddo; Ostritsky, Regina; Richter, Franziska; Zhu, Chunni; Fleming, Sheila M; Lemesre, Vincent; Stewart, Alistair J; Morimoto, Bruce H; Gozes, Illana; Chesselet, Marie-Françoise

    2014-10-01

    Genome-wide association studies have identified strong associations between the risk of developing Parkinson's disease (PD) and polymorphisms in the genes encoding α-synuclein and the microtubule-associated protein tau. However, the contribution of tau and its phosphorylated form (p-tau) to α-synuclein-induced pathology and neuronal dysfunction remains controversial. We have assessed the effects of NAP (davunetide), an eight-amino acid peptide that decreases tau hyperphosphorylation, in mice overexpressing wild-type human α-synuclein (Thy1-aSyn mice), a model that recapitulates aspects of PD. We found that the p-tau/tau level increased in a subcortical tissue block that includes the striatum and brain stem, and in the cerebellum of the Thy1-aSyn mice compared to nontransgenic controls. Intermittent intranasal NAP administration at 2 μg/mouse per day, 5 days a week, for 24 weeks, starting at 4 weeks of age, significantly decreased the ratio of p-tau/tau levels in the subcortical region while a higher dose of 15 μg/mouse per day induced a decrease in p-tau/tau levels in the cerebellum. Both NAP doses reduced hyperactivity, improved habituation to a novel environment, and reduced olfactory deficits in the Thy1-aSyn mice, but neither dose improved the severe deficits of motor coordination observed on the challenging beam and pole, contrasting with previous data obtained with continuous daily administration of the drug. The data reveal novel effects of NAP on brain p-tau/tau and behavioral outcomes in this model of synucleinopathy and suggest that sustained exposure to NAP may be necessary for maximal benefits.

  11. Development of an in vivo model of Chlamydia abortus chronic infection in mice overexpressing IL-10.

    Science.gov (United States)

    Del Río, Laura; Murcia, Antonio; Buendía, Antonio J; Álvarez, Daniel; Ortega, Nieves; Navarro, José A; Salinas, Jesús; Caro, María Rosa

    2018-01-01

    Chlamydia abortus, like other members of the family Chlamydiaceae, have a unique intracellular developmental cycle that is characterized by its chronic nature. Infection of a flock can remain undetected for months, until abortion occurs the following reproductive season but, to date, neither the location nor the mechanisms that maintain this latent phase are fully understood. Studies have shown that IL-10 produced as a response to certain micro-organisms sustains the intracellular survival of pathogens and increases host susceptibility to chlamydial infections. In order to induce a sustained infection C. abortus, transgenic mice that constitutively express IL-10 were infected and the immunological mechanisms that maintain infection in these mice were compared with the mechanisms of a resistant wild-type mouse strain. Viable bacteria could be detected in different tissues of transgenic mice up to 28 days after infection, as analysed by bacterial isolation and immunohistochemistry. Chronic infection in these mice was associated with an impaired recruitment of macrophages, decreased iNOS activity at the site of infection and a more diffuse distribution of inflammatory cells in the liver. This murine model can be of great help for understanding the immunological and bacterial mechanisms that lead to chronic chlamydial infections. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Skeletal muscle-specific overexpression of IGFBP-2 promotes a slower muscle phenotype in healthy but not dystrophic mdx mice and does not affect the dystrophic pathology.

    Science.gov (United States)

    Swiderski, Kristy; Martins, Karen Janet Bernice; Chee, Annabel; Trieu, Jennifer; Naim, Timur; Gehrig, Stefan Martin; Baum, Dale Michael; Brenmoehl, Julia; Chau, Luong; Koopman, René; Gregorevic, Paul; Metzger, Friedrich; Hoeflich, Andreas; Lynch, Gordon Stuart

    The insulin-like growth factor binding proteins (IGFBPs) are thought to modulate cell size and homeostasis via IGF-I-dependent and -independent pathways. There is a considerable dearth of information regarding the function of IGFBPs in skeletal muscle, particularly their role in the pathophysiology of Duchenne muscular dystrophy (DMD). In this study we tested the hypothesis that intramuscular IGFBP-2 overexpression would ameliorate the pathology in mdx dystrophic mice. 4week old male C57Bl/10 and mdx mice received a single intramuscular injection of AAV6-empty or AAV6-IGFBP-2 vector into the tibialis anterior muscle. At 8weeks post-injection the effect of IGFBP-2 overexpression on the structure and function of the injected muscle was assessed. AAV6-mediated IGFBP-2 overexpression in the tibialis anterior (TA) muscles of 4-week-old C57BL/10 and mdx mice reduced the mass of injected muscle after 8weeks, inducing a slower muscle phenotype in C57BL/10 but not mdx mice. Analysis of inflammatory and fibrotic gene expression revealed no changes between control and IGFBP-2 injected muscles in dystrophic (mdx) mice. Together these results indicate that the IGFBP-2-induced promotion of a slower muscle phenotype is impaired in muscles of dystrophin-deficient mdx mice, which contributes to the inability of IGFBP-2 to ameliorate the dystrophic pathology. The findings implicate the dystrophin-glycoprotein complex (DGC) in the signaling required for this adaptation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Human paraoxonase gene cluster overexpression alleviates angiotensin II-induced cardiac hypertrophy in mice.

    Science.gov (United States)

    Pei, Jian-Fei; Yan, Yun-Fei; Tang, Xiaoqiang; Zhang, Yang; Cui, Shen-Shen; Zhang, Zhu-Qin; Chen, Hou-Zao; Liu, De-Pei

    2016-11-01

    Cardiac hypertrophy is the strongest predictor of the development of heart failure, and anti-hypertrophic treatment holds the key to improving the clinical syndrome and increasing the survival rates for heart failure. The paraoxonase (PON) gene cluster (PC) protects against atherosclerosis and coronary artery diseases. However, the role of PC in the heart is largely unknown. To evaluate the roles of PC in cardiac hypertrophy, transgenic mice carrying the intact human PON1, PON2, and PON3 genes and their flanking sequences were studied. We demonstrated that the PC transgene (PC-Tg) protected mice from cardiac hypertrophy induced by Ang II; these mice had reduced heart weight/body weight ratios, decreased left ventricular wall thicknesses and increased fractional shortening compared with wild-type (WT) control. The same protective tendency was also observed with an Apoe -/- background. Mechanically, PC-Tg normalized the disequilibrium of matrix metalloproteinases (MMPs)/tissue inhibitors of MMPs (TIMPs) in hypertrophic hearts, which might contribute to the protective role of PC-Tg in cardiac fibrosis and, thus, protect against cardiac remodeling. Taken together, our results identify a novel anti-hypertrophic role for the PON gene cluster, suggesting a possible strategy for the treatment of cardiac hypertrophy through elevating the levels of the PON gene family.

  14. Heart-specific overexpression of (pro)renin receptor induces atrial fibrillation in mice.

    Science.gov (United States)

    Lian, Hong; Wang, Xiaojian; Wang, Juan; Liu, Ning; Zhang, Li; Lu, Yingdong; Yang, Yanmin; Zhang, Lianfeng

    2015-04-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia, causing substantial cardiovascular morbidity and mortality. The renin-angiotensin system (RAS) has been shown to be involved in the pathophysiology of AF. The (pro)renin receptor [(p)RR] is the last identified member of RAS. However, the role of (p)RR in AF is still unknown. Circulating levels of (p)RR were determined using an immunosorbent assay in 22 patients with AF (paroxysmal or persistent) and 22 healthy individuals. The plasma levels of (p)RR increased 3.6-fold in AF patients (Patrial flutter since 2 months, then spontaneously converted to atrial fibrillation by 10 months. The atria of the transgenic mice demonstrated significant dilation and fibrosis, and exhibited a high incidence of sudden death. Additionally, the genes of SERCA and HCN4, which are involved in the electrophysiology of AF, were significantly down-regulated and up-regulated respectively in transgenic mice atria. The phosphorylation of Erk1/2 significantly increased in the atria of the transgenic mice, and the activated Erk1/2 was found predominantly in cardiac fibroblasts, suggesting that the transgenic (p)RR gene may induce atrial fibrillation by activation of Erk1/2 in the cardiac fibroblasts of the atria. (p)RR promotes atrial structural and electrical remodeling in vivo, which indicates that (p)RR plays an important role in the pathological development of AF. Copyright © 2015. Published by Elsevier Ireland Ltd.

  15. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis

    Science.gov (United States)

    Won, Hee-Young; Jang, Ki-Seok; Min, Kyueng-Whan; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-01-01

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in the mammary glands of MMTV-Id1 transgenic mice. Furthermore, MMTV-Id1 mice develop ductal hyperplasia and mammary tumors with highly expressed basal markers. Id1 also increases breast cancer stem cell (CSC) population and activity in human breast cancer lines. Moreover, the effects of Id1 on normal and malignant stem cell activities are mediated by the Wnt/c-Myc pathway. Collectively, these findings provide in vivo genetic evidence of Id1 functions as an oncogene in breast cancer and indicate that Id1 regulates mammary basal stem cells by activating the Wnt/c-Myc pathway, thereby contributing to breast tumor development. PMID:25938540

  16. Triggered Firing and Atrial Fibrillation in Transgenic Mice With Selective Atrial Fibrosis Induced by Overexpression of TGF-β1

    Science.gov (United States)

    Choi, Eue-Keun; Chang, Po-Cheng; Lee, Young-Soo; Lin, Shien-Fong; Zhu, Wuqiang; Maruyama, Mitsunori; Fishbein, Michael C.; Chen, Zhenhui; der Lohe, Michael Rubart-von; Field, Loren J.; Chen, Peng-Sheng

    2013-01-01

    Background Calcium transient triggered firing (CTTF) is induced by large intracellular calcium (Cai) transient and short action potential duration (APD). We hypothesized that CTTF underlies the mechanisms of early afterdepolarization (EAD) and spontaneous recurrent atrial fibrillation (AF) in transgenic (Tx) mice with overexpression of transforming growth factor β1 (TGF-β1). Methods and Results MHC-TGFcys33ser Tx mice develop atrial fibrosis because of elevated levels of TGF-β1. We studied membrane potential and Cai transients of isolated superfused atria from Tx and wild-type (Wt) littermates. Short APD and persistently elevated Cai transients promoted spontaneous repetitive EADs, triggered activity and spontaneous AF after cessation of burst pacing in Tx but not Wt atria (39% vs. 0%, P=0.008). We were able to map optically 4 episodes of spontaneous AF re-initiation. All first and second beats of spontaneous AF originated from the right atrium (4/4, 100%), which is more severely fibrotic than the left atrium. Ryanodine and thapsigargin inhibited spontaneous re-initiation of AF in all 7 Tx atria tested. Western blotting showed no significant changes of calsequestrin or sarco/endoplasmic reticulum Ca2+-ATPase 2a. Conclusions Spontaneous AF may occur in the Tx atrium because of CTTF, characterized by APD shortening, prolonged Cai transient, EAD and triggered activity. Inhibition of Ca2+ release from the sarcoplasmic reticulum suppressed spontaneous AF. Our results indicate that CTTF is an important arrhythmogenic mechanism in TGF-β1 Tx atria. PMID:22447020

  17. A53T Human α-Synuclein Overexpression in Transgenic Mice Induces Pervasive Mitochondria Macroautophagy Defects Preceding Dopamine Neuron Degeneration

    Science.gov (United States)

    Xie, Zhiguo; Turkson, Susie

    2015-01-01

    In vitro evidence suggests that the inefficient removal of damaged mitochondria by macroautophagy contributes to Parkinson's disease (PD). Using a tissue-specific gene amplification strategy, we generated a transgenic mouse line with human α-synuclein A53T overexpression specifically in dopamine (DA) neurons. Transgenic mice showed profound early-onset mitochondria abnormalities, characterized by macroautophagy marker-positive cytoplasmic inclusions containing mainly mitochondrial remnants, which preceded the degeneration of DA neurons. Genetic deletion of either parkin or PINK1 in these transgenic mice significantly worsened mitochondrial pathologies, including drastically enlarged inclusions and loss of total mitochondria contents. These data suggest that mitochondria are the main targets of α-synuclein and their defective autophagic clearance plays a significant role during pathogenesis. Moreover, endogenous PINK1 or parkin is indispensable for the proper autophagic removal of damaged mitochondria. Our data for the first time establish an essential link between mitochondria macroautophagy impairments and DA neuron degeneration in an in vivo model based on known PD genetics. The model, its well-defined pathologies, and the demonstration of a main pathogenesis pathway in the present study have set the stage and direction of emphasis for future studies. PMID:25609609

  18. Impact of CYP24A1 overexpression on growth of colorectal tumour xenografts in mice fed with vitamin D and soy.

    Science.gov (United States)

    Höbaus, Julia; Tennakoon, Samawansha; Heffeter, Petra; Groeschel, Charlotte; Aggarwal, Abhishek; Hummel, Doris M; Thiem, Ursula; Marculescu, Rodrig; Berger, Walter; Kállay, Enikö

    2016-01-15

    Our previous studies showed that the 1,25-dihydroxyvitamin D (1,25-D3) catabolizing enzyme, 1,25-dihydoxyvitamin D 24 hydroxylase (CYP24A1) was overexpressed in colorectal tumours and its level correlated with increased proliferation. We hypothesised that cells overexpressing CYP24A1 have growth advantage and a diet rich in vitamin D and soy would restore sensitivity to the anti-tumourigenic effects of vitamin D. Soy contains genistein, a natural CYP24A1 inhibitor. To determine causality between CYP24A1 and tumour growth, we established xenografts in male SCID mice with HT29 cells stably overexpressing either GFP-tagged CYP24A1 or GFP. Mice were fed with either high (2500 IU D3/kg) or low vitamin D (100 IU D3/kg) diet in the presence or absence of soy (20% diet). In vitro, cells overexpressing CYP24A1 grew faster than controls. 1,25-D3, the active vitamin D metabolite, reduced cell number only in the presence of the CYP24A1 inhibitor VID400. Regardless of the amount of vitamin D in the diet, xenografts overexpressing CYP24A1 grew faster, were heavier and more aggressive. Soy reduced tumour volume only in the control xenografts, while the tumours overexpressing CYP24A1 were larger in the presence of dietary soy. In conclusion, we demonstrate that CYP24A1 overexpression results in increased aggressiveness and proliferative potential of colorectal tumours. Irrespective of the dietary vitamin D3, dietary soy is able to increase tumour volume when tumours overexpress CYP24A1, suggesting that combination of vitamin D3 and soy could have an anti-tumourigenic effect only if CYP24A1 levels are normal. © 2015 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

  19. Overexpression of eIF-5A2 in mice causes accelerated organismal aging by increasing chromosome instability

    Directory of Open Access Journals (Sweden)

    Chen Leilei

    2011-05-01

    Full Text Available Abstract Background Amplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene eIF-5A2 within the 3q26 region. Functional study has demonstrated the oncogenic role of eIF-5A2 in the initiation and progression of human cancers. In the present study, we aim to investigate the physiological and pathological effect of eIF-5A2 in an eIF-5A2 transgenic mouse model. Methods An eIF-5A2 transgenic mouse model was generated using human eIF-5A2 cDNA. The eIF-5A2 transgenic mice were characterized by histological and immunohistochemistry analyses. The aging phenotypes were further characterized by wound healing, bone X-ray imaging and calcification analysis. Mouse embryo fibroblasts (MEF were isolated to further investigate molecular mechanism of eIF-5A2 in aging. Results Instead of resulting in spontaneous tumor formation, overexpression of eIF-5A2 accelerated the aging process in adult transgenic mice. This included decreased growth rate and body weight, shortened life span, kyphosis, osteoporosis, delay of wound healing and ossification. Investigation of the correlation between cellular senescence and aging showed that cellular senescence is not required for the aging phenotypes in eIF-5A2 mice. Interestingly, we found that activation of eIF-5A2 repressed p19 level and therefore destabilized p53 in transgenic mouse embryo fibroblast (MEF cells. This subsequently allowed for the accumulation of chromosomal instability, such as errors in cell dividing during metaphase and anaphase. Additionally, a significantly increase in number of aneuploidy cells (p Conclusion These observations suggest that eIF-5A2 mouse models could accelerate organismal aging by increasing chromosome instability.

  20. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Søderman, Andreas; Thomsen, Morten Skøtt; Hansen, Henrik H

    2008-01-01

    systemic administration of the alpha7 nAChR agonist SSR180711 (10 mg/kg) result in a significant increase in Fos protein levels in the shell of nucleus accumbens in wild-type mice, but has no effect in the transgene mice. There were fewer cell bodies expressing Fos in the prefrontal cortex of transgene...... mice, and in this region no induction was achieved after administration with SSR180711 in either of the two groups. These results suggest that overexpression of human Abeta peptides perhaps via direct interaction with alpha7 nAChR, inhibit alpha7 nAChR-dependent neurotransmission in vivo and emphasize...

  1. StAR overexpression decreases serum and tissue lipids in apolipoprotein E-deficient mice

    Science.gov (United States)

    Ning, Yanxia; Xu, Leyuan; Ren, Shunlin; Pandak, William M.; Chen, Sifeng; Yin, Lianhua

    2010-01-01

    Cholesterol metabolism as initiated by mitochondrial CYP27A1 is a ubiquitous pathway capable of synthesizing multiple key regulatory oxysterols involved in lipids homeostasis. Previously we have shown that the regulation of its activities within hepatocytes is highly controlled by the rate of mitochondrial cholesterol delivery. In the present study, we hypothesized that increasing expression of the mitochondrial cholesterol delivery protein, StAR, is able to lower lipids accumulation in liver, aortic wall, as well as in serum in a well-documented animal model, apoE−/− mice. ApoE−/− mice, characterized by increased serum, liver, and endothelial cholesterol and triglyceride levels by 3 months of age, were infected with recombinant CMV-StAR adenovirus to increase StAR protein expression. Six days following infection, serum total cholesterol and triglycerides had decreased 19 % (P80% (Plipid staining. This study demonstrates for the first time a possible therapeutic role of the CYP27A1–initiated pathway in the treatment of dyslipidemias. PMID:19373502

  2. Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles.

    Science.gov (United States)

    Hojman, Pernille; Brolin, Camilla; Gissel, Hanne; Brandt, Claus; Zerahn, Bo; Pedersen, Bente Klarlund; Gehl, Julie

    2009-06-12

    Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (Pdiet,) 21.9+/-1.4 g (EPO, normal diet), 35.3+/-3.3 g (control, high-fat diet) and 28.8+/-2.6 g (EPO, high-fat diet). Correspondingly, DXA scanning revealed that this was due to a 28% reduction in adipose tissue mass.The decrease in adipose tissue mass was accompanied by a complete normalisation of fasting insulin levels and glucose tolerance in the high-fat fed mice. EPO expression also induced a 14% increase in muscle volume and a 25% increase in vascularisation of the EPO transfected muscle. Muscle force and stamina were not affected by EPO expression. PCR array analysis revealed that genes involved in lipid metabolism, thermogenesis and inflammation were increased in muscles in response to EPO expression, while genes involved in glucose metabolism were down-regulated. In addition, muscular fat oxidation was increased 1.8-fold in both the EPO transfected and contralateral muscles.In conclusion, we have shown that EPO when expressed in supra-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles.

  3. Transgenic mice overexpressing glia maturation factor-β, an oxidative stress inducible gene, show premature aging due to Zmpste24 down-regulation.

    Science.gov (United States)

    Imai, Rika; Asai, Kanae; Hanai, Jun-ichi; Takenaka, Masaru

    2015-07-01

    Glia Maturation Factor-β (GMF), a brain specific protein, is induced by proteinuria in renal tubules. Ectopic GMF overexpression causes apoptosisin vitro via cellular vulnerability to oxidative stress. In order to examine the roles of GMF in non-brain tissue, we constructed transgenic mice overexpressing GMF (GMF-TG). The GMF-TG mice exhibited appearance phenotypes associated with premature aging. The GMF-TG mice also demonstrated short lifespans and reduced hair regrowth, suggesting an accelerated aging process. The production of an abnormal lamin A, a nuclear envelope protein, plays a causal role in both normal aging and accelerated aging diseases, known as laminopathies. Importantly, we identified the abnormal lamin A (prelamin A), accompanied by a down-regulation of a lamin A processing enzyme (Zmpste24) in the kidney of the GMF-TG mice. The GMF-TG mice showed accelerated aging in the kidney, compared with wild-type mice, showing increased TGF-β1, CTGF gene and serum creatinine. The gene expression of p21/waf1 was increased at an earlier stage of life, at 10 weeks, which was in turn down-regulated at a later stage, at 60 weeks. In conclusion, we propose that GMF-TG mice might be a novel mouse model of accelerated aging, due to the abnormal lamin A.

  4. Impaired embryonic development in mice overexpressing the RNA-binding protein TIAR.

    Directory of Open Access Journals (Sweden)

    Yacine Kharraz

    Full Text Available BACKGROUND: TIA-1-related (TIAR protein is a shuttling RNA-binding protein involved in several steps of RNA metabolism. While in the nucleus TIAR participates to alternative splicing events, in the cytoplasm TIAR acts as a translational repressor on specific transcripts such as those containing AU-Rich Elements (AREs. Due to its ability to assemble abortive pre-initiation complexes coalescing into cytoplasmic granules called stress granules, TIAR is also involved in the general translational arrest observed in cells exposed to environmental stress. However, the in vivo role of this protein has not been studied so far mainly due to severe embryonic lethality upon tiar invalidation. METHODOLOGY/PRINCIPAL FINDINGS: To examine potential TIAR tissue-specificity in various cellular contexts, either embryonic or adult, we constructed a TIAR transgenic allele (loxPGFPloxPTIAR allowing the conditional expression of TIAR protein upon Cre recombinase activity. Here, we report the role of TIAR during mouse embryogenesis. We observed that early TIAR overexpression led to low transgene transmission associated with embryonic lethality starting at early post-implantation stages. Interestingly, while pre-implantation steps evolved correctly in utero, in vitro cultured embryos were very sensitive to culture medium. Control and transgenic embryos developed equally well in the G2 medium, whereas culture in M16 medium led to the phosphorylation of eIF2alpha that accumulated in cytoplasmic granules precluding transgenic blastocyst hatching. Our results thus reveal a differential TIAR-mediated embryonic response following artificial or natural growth environment. CONCLUSIONS/SIGNIFICANCE: This study reports the importance of the tightly balanced expression of the RNA-binding protein TIAR for normal embryonic development, thereby emphasizing the role of post-transcriptional regulations in early embryonic programming.

  5. Early and rapid development of insulin resistance, islet dysfunction and glucose intolerance after high-fat feeding in mice overexpressing phosphodiesterase 3B

    DEFF Research Database (Denmark)

    Walz, Helena A; Härndahl, Linda; Wierup, Nils

    2006-01-01

    Inadequate islet adaptation to insulin resistance leads to glucose intolerance and type 2 diabetes. Here we investigate whether beta-cell cAMP is crucial for islet adaptation and prevention of glucose intolerance in mice. Mice with a beta-cell-specific, 2-fold overexpression of the c......AMP-degrading enzyme phosphodiesterase 3B (RIP-PDE3B/2 mice) were metabolically challenged with a high-fat diet. We found that RIP-PDE3B/2 mice early and rapidly develop glucose intolerance and insulin resistance, as compared with wild-type littermates, after 2 months of high-fat feeding. This was evident from....../2 mice. We conclude that accurate regulation of beta-cell cAMP is necessary for adequate islet adaptation to a perturbed metabolic environment and protective for the development of glucose intolerance and insulin resistance....

  6. Cardiac-specific inducible overexpression of human plasma membrane Ca2+ ATPase 4b is cardioprotective and improves survival in mice following ischemic injury.

    Science.gov (United States)

    Sadi, Al Muktafi; Afroze, Talat; Siraj, M Ahsan; Momen, Abdul; White-Dzuro, Colin; Zarrin-Khat, Dorrin; Handa, Shivalika; Ban, Kiwon; Kabir, M Golam; Trivieri, Maria G; Gros, Robert; Backx, Peter; Husain, Mansoor

    2018-03-30

    Background: Heart failure (HF) is associated with reduced expression of plasma membrane Ca 2+ -ATPase 4 (PMCA4). Cardiac-specific overexpression of human PMCA4b in mice inhibited nNOS activity and reduced cardiac hypertrophy by inhibiting calcineurin. Here we examine temporally regulated cardiac-specific overexpression of hPMCA4b in mouse models of myocardial ischemia reperfusion injury (IRI) ex vivo , and HF following experimental myocardial infarction (MI) in vivo Methods and results: Doxycycline-regulated cardiomyocyte-specific overexpression and activity of hPMCA4b produced adaptive changes in expression levels of Ca 2+ -regulatory genes, and induced hypertrophy without significant differences in Ca 2+ transients or diastolic Ca 2+ concentrations. Total cardiac NOS and nNOS-specific activities were reduced in mice with cardiac overexpression of hPMCA4b while nNOS, eNOS and iNOS protein levels did not differ. hMPCA4b-overexpressing mice also exhibited elevated systolic blood pressure vs. controls, with increased contractility and lusitropy in vivo In isolated hearts undergoing IRI, hPMCA4b overexpression was cardioprotective. NO donor-treated hearts overexpressing hPMCA4b showed reduced LVDP and larger infarct size versus vehicle-treated hearts undergoing IRI, demonstrating that the cardioprotective benefits of hPMCA4b-repressed nNOS are lost by restoring NO availability. Finally, both pre-existing and post-MI induction of hPMCA4b overexpression reduced infarct expansion and improved survival from HF. Conclusions: Cardiac PMCA4b regulates nNOS activity, cardiac mass and contractility, such that PMCA4b overexpression preserves cardiac function following IRI, heightens cardiac performance and limits infarct progression, cardiac hypertrophy and HF, even when induced late post-MI. These data identify PMCA4b as a novel therapeutic target for IRI and HF. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  7. Astrocyte-Specific Overexpression of Insulin-Like Growth Factor-1 Protects Hippocampal Neurons and Reduces Behavioral Deficits following Traumatic Brain Injury in Mice.

    Directory of Open Access Journals (Sweden)

    Sindhu K Madathil

    Full Text Available Traumatic brain injury (TBI survivors often suffer from long-lasting cognitive impairment that stems from hippocampal injury. Systemic administration of insulin-like growth factor-1 (IGF-1, a polypeptide growth factor known to play vital roles in neuronal survival, has been shown to attenuate posttraumatic cognitive and motor dysfunction. However, its neuroprotective effects in TBI have not been examined. To this end, moderate or severe contusion brain injury was induced in mice with conditional (postnatal overexpression of IGF-1 using the controlled cortical impact (CCI injury model. CCI brain injury produces robust reactive astrocytosis in regions of neuronal damage such as the hippocampus. We exploited this regional astrocytosis by linking expression of hIGF-1 to the astrocyte-specific glial fibrillary acidic protein (GFAP promoter, effectively targeting IGF-1 delivery to vulnerable neurons. Following brain injury, IGF-1Tg mice exhibited a progressive increase in hippocampal IGF-1 levels which was coupled with enhanced hippocampal reactive astrocytosis and significantly greater GFAP levels relative to WT mice. IGF-1 overexpression stimulated Akt phosphorylation and reduced acute (1 and 3d hippocampal neurodegeneration, culminating in greater neuron survival at 10d after CCI injury. Hippocampal neuroprotection achieved by IGF-1 overexpression was accompanied by improved motor and cognitive function in brain-injured mice. These data provide strong support for the therapeutic efficacy of increased brain levels of IGF-1 in the setting of TBI.

  8. Overexpression of miR-155 in the Liver of Transgenic Mice Alters the Expression Profiling of Hepatic Genes Associated with Lipid Metabolism

    Science.gov (United States)

    Li, Wei; Wang, Xiaoyan; Wei, Jieqiong; Lin, Xia; Zeng, Hui; Yao, Longping; Chen, Xuebing; Zhuang, Jingshen; Weng, Jie; Liu, Yu; Lin, Jihong; Wu, Qinghong; Wang, Wanshan; Yao, Kaitai; Xu, Kang; Xiao, Dong

    2015-01-01

    Hepatic expression profiling has revealed miRNA changes in liver diseases, while hepatic miR-155 expression was increased in murine non-alcoholic fatty liver disease, suggesting that miR-155 might regulate the biological process of lipid metabolism. To illustrate the effects of miR-155 gain of function in transgenic mouse liver on lipid metabolism, transgenic mice (i.e., Rm155LG mice) for the conditional overexpression of mouse miR-155 transgene mediated by Cre/lox P system were firstly generated around the world in this study. Rm155LG mice were further crossed to Alb-Cre mice to realize the liver-specific overexpression of miR-155 transgene in Rm155LG/Alb-Cre double transgenic mice which showed the unaltered body weight, liver weight, epididymal fat pad weight and gross morphology and appearance of liver. Furthermore, liver-specific overexpression of miR-155 transgene resulted in significantly reduced levels of serum total cholesterol, triglycerides (TG) and high-density lipoprotein (HDL), as well as remarkably decreased contents of hepatic lipid, TG, HDL and free fatty acid in Rm155LG/Alb-Cre transgenic mice. More importantly, microarray data revealed a general downward trend in the expression profile of hepatic genes with functions typically associated with fatty acid, cholesterol and triglyceride metabolism, which is likely at least partially responsible for serum cholesterol and triglyceride lowering observed in Rm155LG/Alb-Cre mice. In this study, we demonstrated that hepatic overexpression of miR-155 alleviated nonalcoholic fatty liver induced by a high-fat diet. Additionally, carboxylesterase 3/triacylglycerol hydrolase (Ces3/TGH) was identified as a direct miR-155 target gene that is potentially responsible for the partial liver phenotypes observed in Rm155LG/Alb-Cre mice. Taken together, these data from miR-155 gain of function study suggest, for what we believe is the first time, the altered lipid metabolism and provide new insights into the metabolic

  9. Lung tumorigenesis induced by human vascular endothelial growth factor (hVEGF)-A165 overexpression in transgenic mice and amelioration of tumor formation by miR-16.

    Science.gov (United States)

    Tung, Yu-Tang; Huang, Pin-Wu; Chou, Yu-Ching; Lai, Cheng-Wei; Wang, Hsiu-Po; Ho, Heng-Chien; Yen, Chih-Ching; Tu, Chih-Yen; Tsai, Tung-Chou; Yeh, Dah-Cherng; Wang, Jiun-Long; Chong, Kowit-Yu; Chen, Chuan-Mu

    2015-04-30

    Many studies have shown that vascular endothelial growth factor (VEGF), especially the human VEGF-A165 (hVEGF-A165) isoform, is a key proangiogenic factor that is overexpressed in lung cancer. We generated transgenic mice that overexpresses hVEGF-A165 in lung-specific Clara cells to investigate the development of pulmonary adenocarcinoma. In this study, three transgenic mouse strains were produced by pronuclear microinjection, and Southern blot analysis indicated similar patterns of the foreign gene within the genomes of the transgenic founder mice and their offspring. Accordingly, hVegf-A165 mRNA was expressed specifically in the lung tissue of the transgenic mice. Histopathological examination of the lung tissues of the transgenic mice showed that hVEGF-A165 overexpression induced bronchial inflammation, fibrosis, cysts, and adenoma. Pathological section and magnetic resonance imaging (MRI) analyses demonstrated a positive correlation between the development of pulmonary cancer and hVEGF expression levels, which were determined by immunohistochemistry, qRT-PCR, and western blot analyses. Gene expression profiling by cDNA microarray revealed a set of up-regulated genes (hvegf-A165, cyclin b1, cdc2, egfr, mmp9, nrp-1, and kdr) in VEGF tumors compared with wild-type lung tissues. In addition, overexpressing hVEGF-A165 in Clara cells increases CD105, fibrogenic genes (collagen α1, α-SMA, TGF-β1, and TIMP1), and inflammatory cytokines (IL-1, IL-6, and TNF-α) in the lungs of hVEGF-A165-overexpressing transgenic mice as compared to wild-type mice. We further demonstrated that the intranasal administration of microRNA-16 (miR-16) inhibited lung tumor growth by suppressing VEGF expression via the intrinsic and extrinsic apoptotic pathways. In conclusion, hVEGF-A165 transgenic mice exhibited complex alterations in gene expression and tumorigenesis and may be a relevant model for studying VEGF-targeted therapies in lung adenocarcinoma.

  10. Tet1 overexpression leads to anxiety-like behavior and enhanced fear memories via the activation of calcium-dependent cascade through Egr1 expression in mice.

    Science.gov (United States)

    Kwon, Wookbong; Kim, Hyeng-Soo; Jeong, Jain; Sung, Yonghun; Choi, Minjee; Park, Song; Lee, Jinhee; Jang, Soyoung; Kim, Sung Hyun; Lee, Sanggyu; Kim, Myoung Ok; Ryoo, Zae Young

    2018-01-01

    Ten-eleven translocation methylcytosine dioxygenase 1 ( Tet1 ) initiates DNA demethylation by converting 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) at CpG-rich regions of genes, which have key roles in adult neurogenesis and memory. In addition, the overexpression of Tet1 with 5-hmC alteration in patients with psychosis has also been reported, for instance in schizophrenia and bipolar disorders. The mechanism underlying Tet1 overexpression in the brain; however, is still elusive. In the present study, we found that Tet1-transgenic (Tet1-TG) mice displayed abnormal behaviors involving elevated anxiety and enhanced fear memories. We confirmed that Tet1 overexpression affected adult neurogenesis with oligodendrocyte differentiation in the hippocampal dentate gyrus of Tet1-TG mice. In addition, Tet1 overexpression induced the elevated expression of immediate early genes, such as Egr1 , c-fos , Arc , and Bdnf , followed by the activation of intracellular calcium signals ( i.e. , CamKII, ERK, and CREB) in prefrontal and hippocampal neurons. The expression of GABA receptor subunits ( Gabra2 and Gabra4 ) fluctuated in the prefrontal cortex and hippocampus. We evaluated the effects of Tet1 overexpression on intracellular calcium-dependent cascades by activating the Egr1 promoter in vitro Tet1 enhanced Egr1 expression, which may have led to alterations in Gabra2 and Gabra4 expression in neurons. Taken together, we suggest that the Tet1 overexpression in our Tet1-TG mice can be applied as an effective model for studying various stress-related diseases that show hyperactivation of intracellular calcium-dependent cascades in the brain.-Kwon, W., Kim, H.-S., Jeong, J., Sung, Y., Choi, M., Park, S., Lee, J., Jang, S., Kim, S. H., Lee, S., Kim, M. O., Ryoo, Z. Y. Tet1 overexpression leads to anxiety-like behavior and enhanced fear memories via the activation of calcium-dependent cascade through Egr1 expression in mice. © FASEB.

  11. Overexpression of Adenylyl Cyclase Encoded by the Mycobacterium tuberculosis Rv2212 Gene Confers Improved Fitness, Accelerated Recovery from Dormancy and Enhanced Virulence in Mice

    Directory of Open Access Journals (Sweden)

    Margarita O. Shleeva

    2017-08-01

    Full Text Available Earlier we demonstrated that the adenylyl cyclase (AC encoded by the MSMEG_4279 gene plays a key role in the resuscitation and growth of dormant Mycobacterium smegmatis and that overexpression of this gene leads to an increase in intracellular cAMP concentration and prevents the transition of M. smegmatis from active growth to dormancy in an extended stationary phase accompanied by medium acidification. We surmised that the homologous Rv2212 gene of M. tuberculosis (Mtb, the main cAMP producer, plays similar physiological roles by supporting, under these conditions, the active state and reactivation of dormant bacteria. To test this hypothesis, we established Mtb strain overexpressing Rv2212 and compared its in vitro and in vivo growth characteristics with a control strain. In vitro, the AC-overexpressing pMindRv2212 strain demonstrated faster growth in a liquid medium, prolonged capacity to form CFUs and a significant delay or even prevention of transition toward dormancy. AC-overexpressing cells exhibited easier recovery from dormancy. In vivo, AC-overexpressing bacteria demonstrated significantly higher growth rates (virulence in the lungs and spleens of infected mice compared to the control strain, and, unlike the latter, killed mice in the TB-resistant strain before month 8 of infection. Even in the absence of selecting hygromycin B, all pMindRv2212 CFUs retained the Rv2212 insert during in vivo growth, strongly suggesting that AC overexpression is beneficial for bacteria. Taken together, our results indicate that cAMP supports the maintenance of Mtb cells vitality under unfavorable conditions in vitro and their virulence in vivo.

  12. ß-cell specific overexpression of suppressor of cytokine signalling-3 does not protect against multiple low dose streptozotocin induced type 1 diabetes in mice

    DEFF Research Database (Denmark)

    Börjesson, A; Rønn, S G; Karlsen, A E

    2011-01-01

    We investigated the impact of ß-cell specific overexpression of suppressor of cytokine signalling-3 (SOCS-3) on the development of multiple low dose streptozotocin (MLDSTZ) induced Type 1 diabetes and the possible mechanisms involved. MLDSTZ treatment was administered to RIP-SOCS-3 transgenic......RNA in islet cells and secretion of IL-1Ra into culture medium. MLDSTZ treatment caused gradual hyperglycemia both in the wt mice and in the transgenic mice with the latter tending to be more sensitive. In vitro experiments on wt and transgenic islets did not reveal any differences in sensitivity to damaging...

  13. Data file of a deep proteome analysis of the prefrontal cortex in aged mice with progranulin deficiency or neuronal overexpression of progranulin

    Directory of Open Access Journals (Sweden)

    Juliana Heidler

    2016-12-01

    Full Text Available Progranulin deficiency is associated with neurodegeneration in humans and in mice. The mechanisms likely involve progranulin-promoted removal of protein waste via autophagy. We performed a deep proteomic screen of the pre-frontal cortex in aged (13–15 months female progranulin-deficient mice (GRN−/− and mice with inducible neuron-specific overexpression of progranulin (SLICK-GRN-OE versus the respective control mice. Proteins were extracted and analyzed per liquid chromatography/mass spectrometry (LC/MS on a Thermo Scientific™ Q Exactive Plus equipped with an ultra-high performance liquid chromatography unit and a Nanospray Flex Ion-Source. Full Scan MS-data were acquired using Xcalibur and raw files were analyzed using the proteomics software Max Quant. The mouse reference proteome set from uniprot (June 2015 was used to identify peptides and proteins. The DiB data file is a reduced MaxQuant output and includes peptide and protein identification, accession numbers, protein and gene names, sequence coverage and label free quantification (LFQ values of each sample. Differences in protein expression in genotypes are presented in "Progranulin overexpression in sensory neurons attenuates neuropathic pain in mice: Role of autophagy" (C. Altmann, S. Hardt, C. Fischer, J. Heidler, H.Y. Lim, A. Haussler, B. Albuquerque, B. Zimmer, C. Moser, C. Behrends, F. Koentgen, I. Wittig, M.H. Schmidt, A.M. Clement, T. Deller, I. Tegeder, 2016 [1].

  14. Brain abnormalities and glioma-like lesions in mice overexpressing the long isoform of PDGF-A in astrocytic cells.

    Directory of Open Access Journals (Sweden)

    Inga Nazarenko

    2011-04-01

    Full Text Available Deregulation of platelet-derived growth factor (PDGF signaling is a hallmark of malignant glioma. Two alternatively spliced PDGF-A mRNAs have been described, corresponding to a long (L and a short (S isoform of PDGF-A. In contrast to PDGF-A(S, the PDGF-A(L isoform has a lysine and arginine rich carboxy-terminal extension that acts as an extracellular matrix retention motif. However, the exact role of PDGF-A(L and how it functionally differs from the shorter isoform is not well understood.We overexpressed PDGF-A(L as a transgene under control of the glial fibrillary acidic protein (GFAP promoter in the mouse brain. This directs expression of the transgene to astrocytic cells and GFAP expressing neural stem cells throughout the developing and adult central nervous system. Transgenic mice exhibited a phenotype with enlarged skull at approximately 6-16 weeks of age and they died between 1.5 months and 2 years of age. We detected an increased number of undifferentiated cells in all areas of transgene expression, such as in the subependymal zone around the lateral ventricle and in the cerebellar medulla. The cells stained positive for Pdgfr-α, Olig2 and NG2 but this population did only partially overlap with cells positive for Gfap and the transgene reporter. Interestingly, a few mice presented with overt neoplastic glioma-like lesions composed of both Olig2 and Gfap positive cell populations and with microvascular proliferation, in a wild-type p53 background.Our findings show that PDGF-A(L can induce accumulation of immature cells in the mouse brain. The strong expression of NG2, Pdgfr-α and Olig2 in PDGF-A(L brains suggests that a fraction of these cells are oligodendrocyte progenitors. In addition, accumulation of fluid in the subarachnoid space and skull enlargement indicate that an increased intracranial pressure contributed to the observed lethality.

  15. Left ventricular remodeling leads to heart failure in mice with cardiac-specific overexpression of VEGF-B167: echocardiography and magnetic resonance imaging study.

    Science.gov (United States)

    Lottonen-Raikaslehto, Line; Rissanen, Riina; Gurzeler, Erika; Merentie, Mari; Huusko, Jenni; Schneider, Jurgen E; Liimatainen, Timo; Ylä-Herttuala, Seppo

    2017-03-01

    Cardiac-specific overexpression of vascular endothelial growth factor (VEGF)-B 167 is known to induce left ventricular hypertrophy due to altered lipid metabolism, in which ceramides accumulate to the heart and cause mitochondrial damage. The aim of this study was to evaluate and compare different imaging methods to find the most sensitive way to diagnose at early stage the progressive left ventricular remodeling leading to heart failure. Echocardiography and cardiovascular magnetic resonance imaging were compared for imaging the hearts of transgenic mice with cardiac-specific overexpression of VEGF-B 167 and wild-type mice from 5 to 14 months of age at several time points. Disease progression was verified by molecular biology methods and histology. We showed that left ventricular remodeling is already ongoing at the age of 5 months in transgenic mice leading to heart failure by the age of 14 months. Measurements from echocardiography and cardiovascular magnetic resonance imaging revealed similar changes in cardiac structure and function in the transgenic mice. Changes in histology, gene expressions, and electrocardiography supported the progression of left ventricular hypertrophy. Longitudinal relaxation time in rotating frame (T 1 ρ ) in cardiovascular magnetic resonance imaging could be suitable for detecting severe fibrosis in the heart. We conclude that cardiac-specific overexpression of VEGF-B 167 leads to left ventricular remodeling at early age and is a suitable model to study heart failure development with different imaging methods. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  16. Genetically-induced Estrogen Receptor Alpha mRNA (Esr1) Overexpression Does Not Adversely Affect Fertility or Penile Development in Male Mice

    Science.gov (United States)

    Heath, John; Abdelmageed, Yazeed; Braden, Tim D.; Williams, Carol S.; Williams, John W.; Paulose, Tessie; Hernandez-Ochoa, Isabel; Gupta, Rupesh; Flaws, Jodi A.; Goyal, Hari O.

    2011-01-01

    Previously, we reported that estrogen receptor alpha mRNA (Esr1) or protein (ESR1) overexpression resulting from neonatal exposure to estrogens in rats was associated with infertility and mal-developed penis characterized by reduced length and weight and abnormal accumulation of fat cells. The objective of this study was to determine if mutant male mice overexpressing Esr1 are naturally infertile or have reduced fertility and/or develop abnormal penis. The fertility parameters, including fertility and fecundity indices, numbers of days from the day of cohabitation to the day of delivery, and numbers of pups per female, were not altered from controls, as a result of Esr1 overexpression. Likewise, penile morphology, including the length, weight, and diameter and os penis development, was not altered from controls. Conversely, weights of the seminal vesicles and bulbospongiosus and levator ani (BS/LA) muscles were significantly (P testosterone concentration were not different from controls. Hence, the genetically-induced Esr1 overexpression alone, without an exogenous estrogen exposure during the neonatal period, is unable to adversely affect the development of the penis as well as other male reproductive organs, except limited, but significant, reductions in weights of the seminal vesicles and BS/LA muscles. PMID:20930192

  17. Over-expression of homologous antigens in a leucine auxotroph of Brucella abortus strain RB51 protects mice against a virulent B. suis challenge.

    Science.gov (United States)

    Rajasekaran, Parthiban; Surendran, Naveen; Seleem, Mohamed N; Sriranganathan, Nammalwar; Schurig, Gerhardt G; Boyle, Stephen M

    2011-04-12

    Infection by members of the Gram-negative bacterial genus Brucella causes brucellosis in a variety of mammals. Brucellosis in swine remains a challenge, as there is no vaccine in the USA approved for use in swine against brucellosis. Here, we developed an improved recombinant Brucella abortus vaccine strain RB51 that could afford protection against Brucella suis infection by over-expressing genes encoding homologous proteins: L7/L12 ribosomal protein, Cu/Zn superoxide dismutase [SOD] and glycosyl-transferase [WboA]. Using strain RB51leuB as a platform and an antibiotic-resistance marker free plasmid, strains RB51leuB/SOD, RB51leuB/SOD/L7/L12 and RB51leuB/SOD/WboA were constructed to over-express the antigens: SOD alone, SOD and ribosomal protein L7/L12 or SOD and glycosyl-transferase, respectively. The ability of these vaccine candidates to protect against a virulent B. suis challenge were evaluated in a mouse model. All vaccine groups protected mice significantly (PBrucella antigens can be over-expressed in strain RB51leuB and elicit protective immune responses against brucellosis. Since the plasmid over-expressing homologous antigens does not carry an antibiotic resistance gene, it complies with federal regulations and therefore could be used to develop safer multi-species vaccines for prevention of brucellosis caused by other species of Brucella. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Over-Expression of Porcine Myostatin Missense Mutant Leads to A Gender Difference in Skeletal Muscle Growth between Transgenic Male and Female Mice.

    Science.gov (United States)

    Ma, Dezun; Gao, Pengfei; Qian, Lili; Wang, Qingqing; Cai, Chunbo; Jiang, Shengwang; Xiao, Gaojun; Cui, Wentao

    2015-08-24

    Myostatin, a transforming growth factor-β family member, is a negative regulator of skeletal muscle development and growth. Piedmontese cattle breeds have a missense mutation, which results in a cysteine to tyrosine substitution in the mature myostatin protein (C313Y). This loss-of-function mutation in myostatin results in a double-muscled phenotype in cattle. Myostatin propeptide is an inhibitor of myostatin activity and is considered a potential agent to stimulate muscle growth in livestock. In this study, we generated transgenic mice overexpressing porcine myostatin missense mutant (pmMS), C313Y, and wild-type porcine myostatin propeptide (ppMS), respectively, to examine their effects on muscle growth in mice. Enhanced muscle growth was observed in both pmMS and ppMS transgenic female mice and also in ppMS transgenic male mice. However, there was no enhanced muscle growth observed in pmMS transgenic male mice. To explore why there is such a big difference in muscle growth between pmMS and ppMS transgenic male mice, the expression level of androgen receptor (AR) mutant AR45 was measured by Western blot. Results indicated that AR45 expression significantly increased in pmMS transgenic male mice while it decreased dramatically in ppMS transgenic male mice. Our data demonstrate that both pmMS and ppMS act as myostatin inhibitors in the regulation of muscle growth, but the effect of pmMS in male mice is reversed by an increased AR45 expression. These results provide useful insight and basic theory to future studies on improving pork quality by genetically manipulating myostatin expression or by regulating myostatin activity.

  19. Corticotropin-releasing factor-overexpressing mice exhibit reduced neuronal activation in the arcuate nucleus and food intake in response to fasting.

    Science.gov (United States)

    Stengel, Andreas; Goebel, Miriam; Million, Mulugeta; Stenzel-Poore, Mary P; Kobelt, Peter; Mönnikes, Hubert; Taché, Yvette; Wang, Lixin

    2009-01-01

    Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulating ghrelin levels, and gastric emptying of a nonnutrient meal. CRF-OE mice injected ip with saline showed a 47 and 44% reduction of 30-min and 4-h cumulative food intake response to an overnight fast, respectively, compared with WT. However, the 30-min food intake decrease induced by ip cholecystokinin (3 microg/kg) and increase by ghrelin (300 microg/kg) were similar in CRF-OE and WT mice. Overnight fasting increased the plasma total ghrelin to similar levels in CRF-OE and WT mice, although CRF-OE mice had a 2-fold reduction of nonfasting ghrelin levels. The number of Fos-immunoreactive cells induced by fasting in the arcuate nucleus was reduced by 5.9-fold in CRF-OE compared with WT mice whereas no significant changes were observed in other hypothalamic nuclei. In contrast, fasted CRF-OE mice displayed a 5.6-fold increase in Fos-immunoreactive cell number in the dorsal motor nucleus of the vagus nerve and a 34% increase in 20-min gastric emptying. These findings indicate that sustained overproduction of hypothalamic CRF in mice interferes with fasting-induced activation of arcuate nucleus neurons and the related hyperphagic response.

  20. Vascular endothelial overexpression of human CYP2J2 (Tie2-CYP2J2 Tr modulates cardiac oxylipin profiles and enhances coronary reactive hyperemia in mice.

    Directory of Open Access Journals (Sweden)

    Ahmad Hanif

    Full Text Available Arachidonic acid is metabolized to epoxyeicosatrienoic acids (EETs by cytochrome (CYP P450 epoxygenases, and to ω-terminal hydroxyeicosatetraenoic acids (HETEs by ω-hydroxylases. EETs and HETEs often have opposite biologic effects; EETs are vasodilatory and protect against ischemia/reperfusion injury, while ω-terminal HETEs are vasoconstrictive and cause vascular dysfunction. Other oxylipins, such as epoxyoctadecaenoic acids (EpOMEs, hydroxyoctadecadienoic acids (HODEs, and prostanoids also have varied vascular effects. Post-ischemic vasodilation in the heart, known as coronary reactive hyperemia (CRH, protects against potential damage to the heart muscle caused by ischemia. The relationship among CRH response to ischemia, in mice with altered levels of CYP2J epoxygenases has not yet been investigated. Therefore, we evaluated the effect of endothelial overexpression of the human cytochrome P450 epoxygenase CYP2J2 in mice (Tie2-CYP2J2 Tr on oxylipin profiles and CRH. Additionally, we evaluated the effect of pharmacologic inhibition of CYP-epoxygenases and inhibition of ω-hydroxylases on CRH. We hypothesized that CRH would be enhanced in isolated mouse hearts with vascular endothelial overexpression of human CYP2J2 through modulation of oxylipin profiles. Similarly, we expected that inhibition of CYP-epoxygenases would reduce CRH, whereas inhibition of ω-hydroxylases would enhance CRH. Compared to WT mice, Tie2-CYP2J2 Tr mice had enhanced CRH, including repayment volume, repayment duration, and repayment/debt ratio (P < 0.05. Similarly, inhibition of ω-hydroxylases increased repayment volume and repayment duration, in Tie2-CYP2J2 Tr compared to WT mice (P < 0.05. Endothelial overexpression of CYP2J2 significantly changed oxylipin profiles, including increased EETs (P < 0.05, increased EpOMEs (P < 0.05, and decreased 8-iso-PGF2α (P < 0.05. Inhibition of CYP epoxygenases with MS-PPOH attenuated CRH (P < 0.05. Ischemia caused a decrease in mid

  1. Mammary Gland Tumor Development in Transgenic Mice Overexpressing Different Isoforms of the CDP/Cux Transcription Factor

    National Research Council Canada - National Science Library

    Cadieux, Chantal

    2008-01-01

    Short CUX1 isoforms were found to be overexpressed in breast cancer cell lines, in human breast tumors and in uterine leiomyomas, suggesting that these proteins play a key role in tumor development and progression...

  2. Mammary Gland Tumor Development in Transgenic Mice Overexpressing Different Isoforms of the CDP/Cux Transcription Factor

    National Research Council Canada - National Science Library

    Cadieux, Chantal

    2007-01-01

    Short CDP/Cux isoforms were found to be overexpressed in breast cancer cell lines, in human breast tumors and in uterine leiomyomas, suggesting that these proteins play a key role in tumor development and progression...

  3. Catalase overexpression prevents nuclear factor erythroid 2-related factor 2 stimulation of renal angiotensinogen gene expression, hypertension, and kidney injury in diabetic mice.

    Science.gov (United States)

    Abdo, Shaaban; Shi, Yixuan; Otoukesh, Abouzar; Ghosh, Anindya; Lo, Chao-Sheng; Chenier, Isabelle; Filep, Janos G; Ingelfinger, Julie R; Zhang, Shao Ling; Chan, John S D

    2014-10-01

    This study investigated the impact of catalase (Cat) overexpression in renal proximal tubule cells (RPTCs) on nuclear factor erythroid 2-related factor 2 (Nrf2) stimulation of angiotensinogen (Agt) gene expression and the development of hypertension and renal injury in diabetic Akita transgenic mice. Additionally, adult male mice were treated with the Nrf2 activator oltipraz with or without the inhibitor trigonelline. Rat RPTCs, stably transfected with plasmid containing either rat Agt or Nrf2 gene promoter, were also studied. Cat overexpression normalized systolic BP, attenuated renal injury, and inhibited RPTC Nrf2, Agt, and heme oxygenase-1 (HO-1) gene expression in Akita Cat transgenic mice compared with Akita mice. In vitro, high glucose level, hydrogen peroxide, and oltipraz stimulated Nrf2 and Agt gene expression; these changes were blocked by trigonelline, small interfering RNAs of Nrf2, antioxidants, or pharmacological inhibitors of nuclear factor-κB and p38 mitogen-activated protein kinase. The deletion of Nrf2-responsive elements in the rat Agt gene promoter abolished the stimulatory effect of oltipraz. Oltipraz administration also augmented Agt, HO-1, and Nrf2 gene expression in mouse RPTCs and was reversed by trigonelline. These data identify a novel mechanism, Nrf2-mediated stimulation of intrarenal Agt gene expression and activation of the renin-angiotensin system, by which hyperglycemia induces hypertension and renal injury in diabetic mice. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  4. Neuronal Glud1 (glutamate dehydrogenase 1) over-expressing mice: increased glutamate formation and synaptic release, loss of synaptic activity, and adaptive changes in genomic expression.

    Science.gov (United States)

    Michaelis, E K; Wang, X; Pal, R; Bao, X; Hascup, K N; Wang, Y; Wang, W-T; Hui, D; Agbas, A; Choi, I-Y; Belousov, A; Gerhardt, G A

    2011-09-01

    Glutamate dehydrogenase 1 (GLUD1) is a mitochondrial enzyme expressed in all tissues, including brain. Although this enzyme is expressed in glutamatergic pathways, its function as a regulator of glutamate neurotransmitter levels is still not well defined. In order to gain an understanding of the role of GLUD1 in the control of glutamate levels and synaptic release in mammalian brain, we generated transgenic (Tg) mice that over-express this enzyme in neurons of the central nervous system. The Tg mice have increased activity of GLUD, as well as elevated levels and increased synaptic and depolarization-induced release of glutamate. These mice suffer age-associated losses of dendritic spines, nerve terminals, and neurons. The neuronal losses and dendrite structural changes occur in select regions of the brain. At the transcriptional level in the hippocampus, cells respond by increasing the expression of genes related to neurite growth and synapse formation, indications of adaptive or compensatory responses to the effects of increases in the release and action of glutamate at synapses. Because these Tg mice live to a relatively old age they are a good model of the effects of a "hyperglutamatergic" state on the aging process in the nervous system. The mice are also useful in defining the molecular pathways affected by the over-activation of GLUD in glutamatergic neurons of the brain and spinal cord. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Changes in Skeletal Muscle and Body Weight on Sleeping Beauty Transposon-Mediated Transgenic Mice Overexpressing Pig mIGF-1.

    Science.gov (United States)

    Gao, Bo; Wang, Wei; Wu, Han; Chen, Cai; Shen, Dan; Wang, Saisai; Chen, Wei; Zhang, Li; Chan, Shuheng; Song, Chengyi

    2018-02-22

    gastrocnemius from 16-week-old transgenic male mice showed that the numbers of myofibers per unit were increased in comparison with those in the wild-type mice. mIGF-1 overexpression in mice skeletal muscle may promote myofibers hypertrophy and muscle production, and increased the average body weight of adult mice. Transgenic mice models can be generated by the mediation of SB transposon with high transgene efficiency.

  6. Epididymal cysteine-rich secretory protein 1 encoding gene is expressed in murine hair follicles and downregulated in mice overexpressing Hoxc13.

    Science.gov (United States)

    Peterson, Ron L; Tkatchenko, Tatiana V; Pruett, Nathanael D; Potter, Christopher S; Jacobs, Donna F; Awgulewitsch, Alexander

    2005-12-01

    Members of the Hox gene family of transcriptional regulators are believed to play essential roles in hair follicle differentiation, although little is known about the molecular mechanisms mediating these putative control functions. Transgenic mice overexpressing Hoxc13 in hair follicles (GC13 mice) exhibit complex phenotypic alterations including hair shaft defects and alopecia, as well as severe epidermal abnormalities. To identify some of the genetic pathways affected by Hoxc13 overexpression in hair, we performed large-scale differential gene expression analysis on the skin of 5-d GC13 versus normal FVB mice using DNA chip assays. A surprising result of these experiments was the identification of the epididymal cysteine-rich secretory protein 1 (Crisp1) gene as one of the genes with the greatest expression differential, in this case with greater than 20-fold downregulation in skin from GC13 mice. Crisp1 encodes a secreted protein that has originally been found to be abundantly expressed in the epididymis, where it plays a role in sperm maturation. We have localized Crisp1 mRNA in 5-d postnatal murine scapular skin by in situ hybridization, showing its expression to be restricted to the medulla of the hair shaft. Furthermore, we provide evidence for specific interaction of Hoxc13 with at least one cognate binding site found in the Crisp1 promoter region, thus supporting the concept of a Hoxc13/Crisp1 regulatory relationship. In summary, these data establish the hair as a novel site for Crisp1 expression where its functional role remains to be determined.

  7. Vascular endothelial overexpression of human CYP2J2 (Tie2-CYP2J2 Tr) modulates cardiac oxylipin profiles and enhances coronary reactive hyperemia in mice.

    Science.gov (United States)

    Hanif, Ahmad; Edin, Matthew L; Zeldin, Darryl C; Morisseau, Christophe; Falck, John R; Nayeem, Mohammed A

    2017-01-01

    Arachidonic acid is metabolized to epoxyeicosatrienoic acids (EETs) by cytochrome (CYP) P450 epoxygenases, and to ω-terminal hydroxyeicosatetraenoic acids (HETEs) by ω-hydroxylases. EETs and HETEs often have opposite biologic effects; EETs are vasodilatory and protect against ischemia/reperfusion injury, while ω-terminal HETEs are vasoconstrictive and cause vascular dysfunction. Other oxylipins, such as epoxyoctadecaenoic acids (EpOMEs), hydroxyoctadecadienoic acids (HODEs), and prostanoids also have varied vascular effects. Post-ischemic vasodilation in the heart, known as coronary reactive hyperemia (CRH), protects against potential damage to the heart muscle caused by ischemia. The relationship among CRH response to ischemia, in mice with altered levels of CYP2J epoxygenases has not yet been investigated. Therefore, we evaluated the effect of endothelial overexpression of the human cytochrome P450 epoxygenase CYP2J2 in mice (Tie2-CYP2J2 Tr) on oxylipin profiles and CRH. Additionally, we evaluated the effect of pharmacologic inhibition of CYP-epoxygenases and inhibition of ω-hydroxylases on CRH. We hypothesized that CRH would be enhanced in isolated mouse hearts with vascular endothelial overexpression of human CYP2J2 through modulation of oxylipin profiles. Similarly, we expected that inhibition of CYP-epoxygenases would reduce CRH, whereas inhibition of ω-hydroxylases would enhance CRH. Compared to WT mice, Tie2-CYP2J2 Tr mice had enhanced CRH, including repayment volume, repayment duration, and repayment/debt ratio (P oxylipin profiles, including increased EETs (P oxylipin profiles, enhances CRH. Inhibition of CYP epoxygenases decreases CRH, whereas inhibition of ω-hydroxylases enhances CRH.

  8. Systemic inhibition and liver-specific over-expression of PAI-1 failed to improve survival in all-inclusive populations or homogenous cohorts of CLP mice.

    Science.gov (United States)

    Raeven, P; Drechsler, S; Weixelbaumer, K M; Bastelica, D; Peiretti, F; Klotz, A; Jafarmadar, M; Redl, H; Bahrami, S; Alessi, M C; Declerck, P J; Osuchowski, M F

    2014-06-01

    The role of plasminogen activator inhibitor type-1 (PAI-1) in abdominal sepsis remains elusive. To study the influence of inhibition and over-expression of PAI-1 upon survival in cecal ligation and puncture (CLP) sepsis. (i) Mice underwent moderate CLP and received 10 mg kg(-1) of either monoclonal anti-PAI-1 (MA-MP6H6) or control (MA-Control) antibody intravenously at 0, 18 or 30 h post-CLP. The 30-h treatment group was additionally stratified into mice predicted to survive (P-SUR) or die (P-DIE) based on IL 6 measured at 24 h post-CLP. (ii) PAI-1 expression was induced with pLIVE.PAI-1 plasmid administered 72 h pre-CLP. Blood was sampled for 5 days and survival was monitored for 28 days. MA-MP6H6 effectively neutralized active PAI-1 and fully restored fibrinolysis while PAI-1 over-expression was liver-specific and correlated with PAI-1 increase in the blood. Without stratification, MA-MP6H6 co-/post-treatment conferred no survival benefit. Prospective stratification (IL-6 cut-off: 14 ng mL(-1) ) suggested increased mortality by MA-MP6H6 treatment in P-SUR that reached 30% difference (vs. MA-Control; P < 0.05) after a retrospective cut-off readjustment to 3.3 ng mL(-1) for better P-SUR homogeneity. Subsequent prospective anti-PAI-1 treatment in P-SUR mice with 3.3 ng mL(-1) cut-off demonstrated a negative but statistically insignificant effect: mortality was higher by 17% after MA-MP6H6 vs. MA-Control. Over-expression of PAI 1 did not alter post-CLP survival. Neither PAI-1 inhibition nor over-expression meaningfully modified inflammatory response and/or organ function. Restoration of fibrinolysis in early abdominal sepsis was not beneficial and it may prove detrimental in subjects with the lowest risk of death, while preemptive PAI-1 up-regulation at the current magnitude was not protective. © 2014 International Society on Thrombosis and Haemostasis.

  9. Rv2629 Overexpression Delays Mycobacterium smegmatis and Mycobacteria tuberculosis Entry into Log-Phase and Increases Pathogenicity of Mycobacterium smegmatis in Mice

    Directory of Open Access Journals (Sweden)

    Dan Liu

    2017-11-01

    Full Text Available Objective: The aim of the present study was to explore the potential biological role of Rv2629 in Mycobacterium smegmatis and Mycobacterium tuberculosis.Methods: Recombinant wild type and mutant Rv2629 strains were constructed. Rv2629 expression was evaluated by real-time PCR and western blot. Microarray and interaction network analyses were used to identify the gene interactions associated with wild type and mutant Rv2629. Bacterial growth was assessed in Balb/c mice infected with wild type and mutant Rv2629 strains using CFU assay and histological analysis of the organs.Results: Overexpression of Rv2629 could delay the entry of the Mycobacterium tuberculosis cells into the log-phase, while Rv2629 decreased the number of ribosomes and the expression of uridylate kinase in Mycobacterium smegmatis. The Gene Ontology (GO and pathway analysis indicated that 122 genes correlated with wild type Rv2629, whereas the Rv2629 mutation led to decrease in the ribosome production, oxidative phosphorylation, and virulence in Mycobacterium tuberculosis. Overexpression of Rv2629 slightly enhanced the drug resistance of Mycobacterium smegmatis to antibiotics, and increased its survival and pathogenicity in Balb/c mice.Conclusion: It is suggested that Rv2629 is involved in the survival of the clinical drug-resistant strain via bacterial growth repression and bacterial persistence induction.

  10. 5-HT2A Receptor Binding in the Frontal Cortex of Parkinson's Disease Patients and Alpha-Synuclein Overexpressing Mice: A Postmortem Study.

    Science.gov (United States)

    Rasmussen, Nadja Bredo; Olesen, Mikkel Vestergaard; Brudek, Tomasz; Plenge, Per; Klein, Anders Bue; Westin, Jenny E; Fog, Karina; Wörtwein, Gitta; Aznar, Susana

    2016-01-01

    The 5-HT2A receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer's disease and related to the disease pathology. Even though Parkinson's disease (PD) is primarily a motor disorder, reports of impaired executive function are also steadily being associated with this disease. Not much is known about the pathophysiology behind this. The aim of this study was thereby twofold: (1) to investigate 5-HT2A receptor binding levels in Parkinson's brains and (2) to investigate whether PD associated pathology, alpha-synuclein (AS) overexpression, could be associated with 5-HT2A alterations. Binding density for the 5-HT2A-specific radioligand [(3)H]-MDL 100.907 was measured in membrane suspensions of frontal cortex tissue from PD patients. Protein levels of AS were further measured using western blotting. Results showed higher AS levels accompanied by increased 5-HT2A receptor binding in PD brains. In a separate study, we looked for changes in 5-HT2A receptors in the prefrontal cortex in 52-week-old transgenic mice overexpressing human AS. We performed region-specific 5-HT2A receptor binding measurements followed by gene expression analysis. The transgenic mice showed lower 5-HT2A binding in the frontal association cortex that was not accompanied by changes in gene expression levels. This study is one of the first to look at differences in serotonin receptor levels in PD and in relation to AS overexpression.

  11. Reversal of P-glycoprotein overexpression by Ginkgo biloba extract in the brains of pentylenetetrazole-kindled and phenytoin-treated mice.

    Science.gov (United States)

    Zhang, Ce; Fan, Qing; Chen, Shu-Liang; Ma, Hui

    2015-08-01

    The purpose of this study was to investigate the combined effects of Ginkgo biloba extract and phenytoin (PHT) sodium as a dose regimen simulating the clinical treatment of patients with epilepsy, on P-glycoprotein (P-GP) overexpression in a pentylenetetrazole-kindled mouse model of epilepsy. Epilepsy was induced by intraperitoneal administration of pentylenetetrazole (40 mg/kg) for 7 days followed by intragastric administration of PHT (40 mg/kg) for 14 days. Thirty mice that developed seizures were randomly divided into three groups and administered PHT as well as the following treatments: saline (negative control); verapamil (20 mg/kg, positive control); and G. biloba (30 mg/kg). Seizure severity was recorded 30 minutes after treatment on Day 4 of drug administration, after which the mice were euthanized, and their brains isolated. Western blots and immunohistochemistry were performed to analyze the expression of P-GP and caspase-3, respectively, in the brain tissue. High-performance liquid chromatography was used to measure the concentrations of PHT in the brains of the treated mice. After 4 consecutive days of treatment, the seizure severity in the mice in the G. biloba extract group was more significantly reduced than the seizure severity in the saline control group, and a significant difference was observed between the G. biloba extract and verapamil control groups (p biloba extract and verapamil than it did in the saline-treated control group (p biloba extract and verapamil showed significantly increased brain PHT concentrations (p biloba extract group was significantly lower than that in the vehicle control group (p biloba. Therefore, this study showed that treatment with G. biloba extract in combination with PHT prevented the upregulation of P-GP expression in mice. Moreover, G. biloba extract decreased seizure severity in pentylenetetrazole-kindled/PHT-treated mice through a mechanism that might be related to the reduction of P-GP expression in the brain

  12. Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

    Science.gov (United States)

    Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

    2017-08-01

    The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  13. Transgenic knockdown of cardiac sodium/glucose cotransporter 1 (SGLT1) attenuates PRKAG2 cardiomyopathy, whereas transgenic overexpression of cardiac SGLT1 causes pathologic hypertrophy and dysfunction in mice.

    Science.gov (United States)

    Ramratnam, Mohun; Sharma, Ravi K; D'Auria, Stephen; Lee, So Jung; Wang, David; Huang, Xue Yin N; Ahmad, Ferhaan

    2014-08-04

    The expression of a novel cardiac glucose transporter, SGLT1, is increased in glycogen storage cardiomyopathy secondary to mutations in PRKAG2. We sought to determine the role of SGLT1 in the pathogenesis of PRKAG2 cardiomyopathy and its role in cardiac structure and function. Transgenic mice with cardiomyocyte-specific overexpression of human T400N mutant PRKAG2 cDNA (TG(T400N)) and transgenic mice with cardiomyocyte-specific RNA interference knockdown of SGLT1 (TG(SGLT1-DOWN)) were crossed to produce double-transgenic mice (TG(T400N)/TG(SGLT1-DOWN)). Tet-off transgenic mice conditionally overexpressing cardiac SGLT1 in the absence of doxycycline were also constructed (TG(SGLT-ON)). Relative to TG(T400N) mice, TG(T400N)/TG(SGLT1-DOWN) mice exhibited decreases in cardiac SGLT1 expression (63% decrease, Pmice had less left ventricular dilation at age 12 weeks compared to TG(T400N) mice. Relative to wildtype (WT) mice, TG(SGLT1-ON) mice exhibited increases in heart/body weight ratio, glycogen content, and markers of cardiac hypertrophy at ages 10 and 20 weeks. TG(SGLT1-ON) mice had increased myocyte size and interstitial fibrosis, and progressive left ventricular dysfunction. When SGLT1 was suppressed after 10 weeks of overexpression (TG(SGLT1-ON/OFF)), there was a reduction in cardiac hypertrophy and improvement in left ventricular failure. Cardiac knockdown of SGLT1 in a murine model of PRKAG2 cardiomyopathy attenuates the disease phenotype, implicating SGLT1 in the pathogenesis. Overexpression of SGLT1 causes pathologic cardiac hypertrophy and left ventricular failure that is reversible. This is the first report of cardiomyocyte-specific transgenic knockdown of a target gene. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  14. Reversal of P-glycoprotein overexpression by Ginkgo biloba extract in the brains of pentylenetetrazole-kindled and phenytoin-treated mice

    Directory of Open Access Journals (Sweden)

    Ce Zhang

    2015-08-01

    Full Text Available The purpose of this study was to investigate the combined effects of Ginkgo biloba extract and phenytoin (PHT sodium as a dose regimen simulating the clinical treatment of patients with epilepsy, on P-glycoprotein (P-GP overexpression in a pentylenetetrazole-kindled mouse model of epilepsy. Epilepsy was induced by intraperitoneal administration of pentylenetetrazole (40 mg/kg for 7 days followed by intragastric administration of PHT (40 mg/kg for 14 days. Thirty mice that developed seizures were randomly divided into three groups and administered PHT as well as the following treatments: saline (negative control; verapamil (20 mg/kg, positive control; and G. biloba (30 mg/kg. Seizure severity was recorded 30 minutes after treatment on Day 4 of drug administration, after which the mice were euthanized, and their brains isolated. Western blots and immunohistochemistry were performed to analyze the expression of P-GP and caspase-3, respectively, in the brain tissue. High-performance liquid chromatography was used to measure the concentrations of PHT in the brains of the treated mice. After 4 consecutive days of treatment, the seizure severity in the mice in the G. biloba extract group was more significantly reduced than the seizure severity in the saline control group, and a significant difference was observed between the G. biloba extract and verapamil control groups (p < 0.05. P-GP expression in the brain more significantly decreased in the mice treated with G. biloba extract and verapamil than it did in the saline-treated control group (p < 0.05. Compared with the saline-treated control group, the mice treated with G. biloba extract and verapamil showed significantly increased brain PHT concentrations (p < 0.05. Furthermore, caspase-3 expression in the brain tissue of the G. biloba extract group was significantly lower than that in the vehicle control group (p < 0.05; this finding demonstrated the neuroprotective effects of G. biloba

  15. Over-expressing the soluble gp130-Fc does not ameliorate methionine and choline deficient diet-induced non alcoholic steatohepatitis in mice.

    Directory of Open Access Journals (Sweden)

    Helene L Kammoun

    Full Text Available Non-alcoholic steatohepatitis (NASH is a liver disease with the potential to lead to cirrhosis and hepatocellular carcinoma. Interleukin-6 (IL-6 has been implicated in the pathogenesis of NASH, with the so-called IL-6 'trans-signaling' cascade being responsible for the pro-inflammatory actions of this cytokine. We aimed to block IL-6 'trans-signaling', using a transgenic mouse that overexpresses human soluble glycoprotein130 (sgp130Fc Tg mice fed a commonly used dietary model of inducing NASH (methionine and choline deficient-diet; MCD diet and hypothesized that markers of NASH would be ameliorated in such mice. Sgp130Fc Tg and littermate control mice were fed a MCD or control diet for 4 weeks. The MCD diet induced many hallmarks of NASH including hepatomegaly, steatosis, and liver inflammation. However, in contrast with other mouse models and, indeed, human NASH, the MCD diet model did not increase the mRNA or protein expression of IL-6. Not surprisingly, therefore, markers of MCD diet-induced NASH were unaffected by sgp130Fc transgenic expression. While the MCD diet model induces many pathophysiological markers of NASH, it does not induce increased IL-6 expression in the liver, a key hallmark of human NASH. We, therefore, caution the use of the MCD diet as a viable mouse model of NASH.

  16. EBI2 overexpression in mice leads to B1 B-cell expansion and chronic lymphocytic leukemia-like B-cell malignancies.

    Science.gov (United States)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau; Kubale, Valentina; Kovalchuk, Alexander L; Daugvilaite, Viktorija; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup; Egerod, Kristoffer L; Bassi, Maria R; Spiess, Katja; Schwartz, Thue W; Wang, Hongsheng; Morse, Herbert C; Holst, Peter J; Rosenkilde, Mette M

    2017-02-16

    Human and mouse chronic lymphocytic leukemia (CLL) develops from CD5 + B cells that in mice and macaques are known to define the distinct B1a B-cell lineage. B1a cells are characterized by lack of germinal center (GC) development, and the B1a cell population is increased in mice with reduced GC formation. As a major mediator of follicular B-cell migration, the G protein-coupled receptor Epstein-Barr virus-induced gene 2 ( EBI2 or GPR183 ) directs B-cell migration in the lymphoid follicles in response to its endogenous ligands, oxysterols. Thus, upregulation of EBI2 drives the B cells toward the extrafollicular area, whereas downregulation is essential for GC formation. We therefore speculated whether increased expression of EBI2 would lead to an expanded B1 cell subset and, ultimately, progression to CLL. Here, we demonstrate that B-cell-targeted expression of human EBI2 (hEBI2) in mice reduces GC-dependent immune responses, reduces total immunoglobulin M (IgM) and IgG levels, and leads to increased proliferation and upregulation of cellular oncogenes. Furthermore, hEBI2 overexpression leads to an abnormally expanded CD5 + B1a B-cell subset (present as early as 4 days after birth), late-onset lymphoid cancer development, and premature death. These findings are highly similar to those observed in CLL patients and identify EBI2 as a promoter of B-cell malignancies.

  17. MsrA Overexpression Targeted to the Mitochondria, but Not Cytosol, Preserves Insulin Sensitivity in Diet-Induced Obese Mice.

    Directory of Open Access Journals (Sweden)

    JennaLynn Hunnicut

    Full Text Available There is growing evidence that oxidative stress plays an integral role in the processes by which obesity causes type 2 diabetes. We previously identified that mice lacking the protein oxidation repair enzyme methionine sulfoxide reductase A (MsrA are particularly prone to obesity-induced insulin resistance suggesting an unrecognized role for this protein in metabolic regulation. The goals of this study were to test whether increasing the expression of MsrA in mice can protect against obesity-induced metabolic dysfunction and to elucidate the potential underlying mechanisms. Mice with increased levels of MsrA in the mitochondria (TgMito MsrA or in the cytosol (TgCyto MsrA were fed a high fat/high sugar diet and parameters of glucose homeostasis were monitored. Mitochondrial content, markers of mitochondrial proteostasis and mitochondrial energy utilization were assessed. TgMito MsrA, but not TgCyto MsrA, mice remain insulin sensitive after high fat feeding, though these mice are not protected from obesity. This metabolically healthy obese phenotype of TgMito MsrA mice is not associated with changes in mitochondrial number or biogenesis or with a reduction of proteostatic stress in the mitochondria. However, our data suggest that increased mitochondrial MsrA can alter metabolic homeostasis under diet-induced obesity by activating AMPK signaling, thereby defining a potential mechanism by which this genetic alteration can prevent insulin resistance without affecting obesity. Our data suggest that identification of targets that maintain and regulate the integrity of the mitochondrial proteome, particular against oxidative damage, may play essential roles in the protection against metabolic disease.

  18. Metalloproteinases control brain inflammation induced by pertussis toxin in mice overexpressing the chemokine CCL2 in the central nervous system

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Buist, Richard; Sun, Xue-Jun

    2006-01-01

    . We used flow cytometry, ultra-small superparamagnetic iron oxide-enhanced magnetic resonance imaging, and immunofluorescent staining to show that encephalopathy involved leukocyte migration across the glia limitans into the brain parenchyma, identifying this as the critical step in inducing clinical...... of metalloproteinase-1, metalloproteinase disintegrins-12, MMP-8, and -10 in brains of Tg mice. Levels of the microglial-associated MP MMP-15 were not affected in control or PTx-treated Tg mice. PTx also up-regulated expression of proinflammatory cytokines IL-1beta and TNF-alpha mRNA in Tg CNS. Weight loss...

  19. Electrocardiographic Characterization of Cardiac Hypertrophy in Mice that Overexpress the ErbB2 Receptor Tyrosine Kinase

    DEFF Research Database (Denmark)

    Sysa-Shah, Polina; Sørensen, Lars L; Abraham, M Roselle

    2015-01-01

    Electrocardiography is an important method for evaluation and risk stratification of patients with cardiac hypertrophy. We hypothesized that the recently developed transgenic mouse model of cardiac hypertrophy (ErbB2(tg)) will display distinct ECG features, enabling WT (wild type) mice...... in other rodent models of cardiac hypertrophy. Furthermore, with appropriate modifications, this method might be translated for use in other species....

  20. Mitochondrial catalase overexpressed transgenic mice are protected against lung fibrosis in part via preventing alveolar epithelial cell mitochondrial DNA damage.

    Science.gov (United States)

    Kim, Seok-Jo; Cheresh, Paul; Jablonski, Renea P; Morales-Nebreda, Luisa; Cheng, Yuan; Hogan, Erin; Yeldandi, Anjana; Chi, Monica; Piseaux, Raul; Ridge, Karen; Michael Hart, C; Chandel, Navdeep; Scott Budinger, G R; Kamp, David W

    2016-12-01

    Alveolar epithelial cell (AEC) injury and mitochondrial dysfunction are important in the development of lung fibrosis. Our group has shown that in the asbestos exposed lung, the generation of mitochondrial reactive oxygen species (ROS) in AEC mediate mitochondrial DNA (mtDNA) damage and apoptosis which are necessary for lung fibrosis. These data suggest that mitochondrial-targeted antioxidants should ameliorate asbestos-induced lung. To determine whether transgenic mice that express mitochondrial-targeted catalase (MCAT) have reduced lung fibrosis following exposure to asbestos or bleomycin and, if so, whether this occurs in association with reduced AEC mtDNA damage and apoptosis. Crocidolite asbestos (100µg/50µL), TiO 2 (negative control), bleomycin (0.025 units/50µL), or PBS was instilled intratracheally in 8-10 week-old wild-type (WT - C57Bl/6J) or MCAT mice. The lungs were harvested at 21d. Lung fibrosis was quantified by collagen levels (Sircol) and lung fibrosis scores. AEC apoptosis was assessed by cleaved caspase-3 (CC-3)/Surfactant protein C (SFTPC) immunohistochemistry (IHC) and semi-quantitative analysis. AEC (primary AT2 cells from WT and MCAT mice and MLE-12 cells) mtDNA damage was assessed by a quantitative PCR-based assay, apoptosis was assessed by DNA fragmentation, and ROS production was assessed by a Mito-Sox assay. Compared to WT, crocidolite-exposed MCAT mice exhibit reduced pulmonary fibrosis as measured by lung collagen levels and lung fibrosis score. The protective effects in MCAT mice were accompanied by reduced AEC mtDNA damage and apoptosis. Similar findings were noted following bleomycin exposure. Euk-134, a mitochondrial SOD/catalase mimetic, attenuated MLE-12 cell DNA damage and apoptosis. Finally, compared to WT, asbestos-induced MCAT AT2 cell ROS production was reduced. Our finding that MCAT mice have reduced pulmonary fibrosis, AEC mtDNA damage and apoptosis following exposure to asbestos or bleomycin suggests an important role

  1. Striatal Transcriptome and Interactome Analysis of Shank3-overexpressing Mice Reveals the Connectivity between Shank3 and mTORC1 Signaling

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    Yeunkum Lee

    2017-06-01

    Full Text Available Mania causes symptoms of hyperactivity, impulsivity, elevated mood, reduced anxiety and decreased need for sleep, which suggests that the dysfunction of the striatum, a critical component of the brain motor and reward system, can be causally associated with mania. However, detailed molecular pathophysiology underlying the striatal dysfunction in mania remains largely unknown. In this study, we aimed to identify the molecular pathways showing alterations in the striatum of SH3 and multiple ankyrin repeat domains 3 (Shank3-overexpressing transgenic (TG mice that display manic-like behaviors. The results of transcriptome analysis suggested that mammalian target of rapamycin complex 1 (mTORC1 signaling may be the primary molecular signature altered in the Shank3 TG striatum. Indeed, we found that striatal mTORC1 activity, as measured by mTOR S2448 phosphorylation, was significantly decreased in the Shank3 TG mice compared to wild-type (WT mice. To elucidate the potential underlying mechanism, we re-analyzed previously reported protein interactomes, and detected a high connectivity between Shank3 and several upstream regulators of mTORC1, such as tuberous sclerosis 1 (TSC1, TSC2 and Ras homolog enriched in striatum (Rhes, via 94 common interactors that we denominated “Shank3-mTORC1 interactome”. We noticed that, among the 94 common interactors, 11 proteins were related to actin filaments, the level of which was increased in the dorsal striatum of Shank3 TG mice. Furthermore, we could co-immunoprecipitate Shank3, Rhes and Wiskott-Aldrich syndrome protein family verprolin-homologous protein 1 (WAVE1 proteins from the striatal lysate of Shank3 TG mice. By comparing with the gene sets of psychiatric disorders, we also observed that the 94 proteins of Shank3-mTORC1 interactome were significantly associated with bipolar disorder (BD. Altogether, our results suggest a protein interaction-mediated connectivity between Shank3 and certain upstream

  2. Mice overexpressing both non-mutated human SOD1 and mutated SOD1G93A genes: a competent experimental model for studying iron metabolism in amyotrophic lateral sclerosis

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    Anna eGajowiak

    2016-01-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a progressive neurodegenerative disease characterized by degeneration and loss of motor neurons in the spinal cord, brainstem and motor cortex. Up to 10% of ALS cases are inherited (familial, fALS and associated with mutations, frequently in the superoxide dismutase 1 (SOD1 gene. Rodent transgenic models of ALS are often used to elucidate a complex pathogenesis of this disease. Of importance, both ALS patients and animals carrying mutated human SOD1 gene show symptoms of oxidative stress and iron metabolism misregulation. The aim of our study was to characterize changes in iron metabolism in one of the most commonly used models of ALS – transgenic mice overexpressing human mutated SOD1G93A gene. We analyzed the expression of iron-related genes in asymptomatic, 2-month old and symptomatic, 4-month old SOD1G93A mice. In parallel, respective age-matched mice overexpressing human non-mutated SOD1 transgene and control mice were analyzed. We demonstrate that the overexpression of both SOD1 and SOD1G93A genes account for a substantial increase in SOD1 protein levels and activity in selected tissues and that not all the changes in iron metabolism genes expression are specific for the overexpression of the mutated form of SOD1.

  3. Early and progressive microstructural brain changes in mice overexpressing human alpha-Synuclein detected by diffusion kurtosis imaging

    Czech Academy of Sciences Publication Activity Database

    Khairnar, A.; Rudá-Kučerová, J.; Szabó, N.; Dražanová, Eva; Arab, A.; Hutter-Paier, B.; Neddens, J.; Latta, P.; Starčuk jr., Zenon; Rektorová, I.

    2017-01-01

    Roč. 61, MAR (2017), s. 197-208 ISSN 0889-1591 R&D Projects: GA MŠk(CZ) LO1212; GA MŠk(CZ) LM2015062; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : MRI * diffusion kurtosis imaging * substantia nigra * sriatum * thalamus * TNWT-61 * parkinson's disease * transgenic mice * animal model Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: 1.7 Other natural sciences Impact factor: 5.964, year: 2016

  4. Increased immunoglobulin A levels in milk by over-expressing the murine polymeric immunoglobulin receptor gene in the mammary gland epithelial cells of transgenic mice.

    Science.gov (United States)

    De Groot, N; Van Kuik-Romeijn, P; Lee, S H; De Boer, H A

    2000-10-01

    The polymeric immunoglobulin receptor (pIgR) transports dimeric immunoglobulin A (dIgA) across the epithelial cell layers into the secretions of various mucosal and glandular surfaces of mammals. At these mucosal sites, such as the gastrointestinal tract, respiratory tract, urogenital tract and the mammary glands, dIgA protects the body against pathogens. The pIgR binds dIgA at the basolateral side and transports it via the complex mechanism of transcytosis to the apical side of the epithelial cells lining the mucosa. Here, the extracellular part of the receptor is cleaved to form the secretory component (SC), which remains associated to dIgA, thereby protecting it from degradation in the secretions. One pIgR molecule transports only one dIgA molecule (1 : 1 ratio) and the pIgR is not recycled after each round of transport. This implies that the amount of available receptor could be a rate-limiting factor determining both the rate and amount of IgA transported per cell and therefore determining the total IgA output into the lumen or, in case of the mammary gland, into the milk. In order to test this hypothesis, we set up an in vivo model system. We generated transgenic mice over-expressing the murine pIgR gene under lactogenic control, by using a milk gene promoter, rather than under immunological control. Mice over-expressing the pIgR protein, in mammary gland epithelial cells, from 60- up to 270-fold above normal pIgR protein levels showed total IgA levels in the milk to be 1.5-2-fold higher, respectively, compared with the IgA levels in the milk of non-transgenic mice. This indicates that the amount of pIgR produced is indeed a limiting factor in the transport of dIgA into the milk under normal non-inflammatory circumstances.

  5. Efficient immunoglobulin gene disruption and targeted replacement in rabbit using zinc finger nucleases.

    Directory of Open Access Journals (Sweden)

    Tatiana Flisikowska

    Full Text Available Rabbits are widely used in biomedical research, yet techniques for their precise genetic modification are lacking. We demonstrate that zinc finger nucleases (ZFNs introduced into fertilized oocytes can inactivate a chosen gene by mutagenesis and also mediate precise homologous recombination with a DNA gene-targeting vector to achieve the first gene knockout and targeted sequence replacement in rabbits. Two ZFN pairs were designed that target the rabbit immunoglobulin M (IgM locus within exons 1 and 2. ZFN mRNAs were microinjected into pronuclear stage fertilized oocytes. Founder animals carrying distinct mutated IgM alleles were identified and bred to produce offspring. Functional knockout of the immunoglobulin heavy chain locus was confirmed by serum IgM and IgG deficiency and lack of IgM(+ and IgG(+ B lymphocytes. We then tested whether ZFN expression would enable efficient targeted sequence replacement in rabbit oocytes. ZFN mRNA was co-injected with a linear DNA vector designed to replace exon 1 of the IgM locus with ∼1.9 kb of novel sequence. Double strand break induced targeted replacement occurred in up to 17% of embryos and in 18% of fetuses analyzed. Two major goals have been achieved. First, inactivation of the endogenous IgM locus, which is an essential step for the production of therapeutic human polyclonal antibodies in the rabbit. Second, establishing efficient targeted gene manipulation and homologous recombination in a refractory animal species. ZFN mediated genetic engineering in the rabbit and other mammals opens new avenues of experimentation in immunology and many other research fields.

  6. Differential levels of glutamate dehydrogenase 1 (GLUD1) in Balb/c and C57BL/6 mice and the effects of overexpression of the Glud1 gene on glutamate release in striatum.

    Science.gov (United States)

    Hascup, Kevin N; Bao, Xiaodong; Hascup, Erin R; Hui, Dongwei; Xu, Wenhao; Pomerleau, Francois; Huettl, Peter; Michaelis, Mary L; Michaelis, Elias K; Gerhardt, Greg A

    2011-04-21

    We have previously shown that overexpression of the Glud1 (glutamate dehydrogenase 1) gene in neurons of C57BL/6 mice results in increased depolarization-induced glutamate release that eventually leads to selective neuronal injury and cell loss by 12 months of age. However, it is known that isogenic lines of Tg (transgenic) mice produced through back-crossing with one strain may differ in their phenotypic characteristics from those produced using another inbred mouse strain. Therefore, we decided to introduce the Glud1 transgene into the Balb/c strain that has endogenously lower levels of GLUD1 (glutamate dehydrogenase 1) enzyme activity in the brain as compared with C57BL/6. Using an enzyme-based MEA (microelectrode array) that is selective for measuring glutamate in vivo, we measured depolarization-induced glutamate release. Within a discrete layer of the striatum, glutamate release was significantly increased in Balb/c Tg mice compared with wt (wild-type) littermates. Furthermore, Balb/c mice released approx. 50-60% of the amount of glutamate compared with C57BL/6 mice. This is similar to the lower levels of endogenous GLUD1 protein in Balb/c compared with C57BL/6 mice. The development of these Glud1-overexpressing mice may allow for the exploration of key molecular events produced by chronic exposure of neurons to moderate, transient increases in glutamate release, a process hypothesized to occur in neurodegenerative disorders.

  7. Role of Nitric Oxide Isoforms in Vascular and Alveolar Development and Lung Injury in Vascular Endothelial Growth Factor Overexpressing Neonatal Mice Lungs.

    Directory of Open Access Journals (Sweden)

    Mansoor A Syed

    Full Text Available The role of vascular endothelial growth factor (VEGF-induced 3 different nitric oxide synthase (NOS isoforms in lung development and injury in the newborn (NB lung are not known. We hypothesized that VEGF-induced specific NOS pathways are critical regulators of lung development and injury.We studied NB wild type (WT, lung epithelial cell-targeted VEGF165 doxycycline-inducible overexpressing transgenic (VEGFTG, VEGFTG treated with a NOS1 inhibitor (L-NIO, VEGFTG x NOS2-/- and VEGFTG x NOS3+/- mice in room air (RA for 7 postnatal (PN days. Lung morphometry (chord length, vascular markers (Ang1, Ang2, Notch2, vWF, CD31 and VE-cadherin, cell proliferation (Ki67, vascular permeability, injury and oxidative stress markers (hemosiderin, nitrotyrosine and 8-OHdG were evaluated.VEGF overexpression in RA led to increased chord length and vascular markers at PN7, which were significantly decreased to control values in VEGFTG x NOS2-/- and VEGFTG x NOS3+/- lungs. However, we found no noticeable effect on chord length and vascular markers in the VEGFTG / NOS1 inhibited group. In the NB VEGFTG mouse model, we found VEGF-induced vascular permeability in the NB murine lung was partially dependent on NOS2 and NOS3-signaling pathways. In addition, the inhibition of NOS2 and NOS3 resulted in a significant decrease in VEGF-induced hemosiderin, nitrotyrosine- and 8-OHdG positive cells at PN7. NOS1 inhibition had no significant effect.Our data showed that the complete absence of NOS2 and partial deficiency of NOS3 confers protection against VEGF-induced pathologic lung vascular and alveolar developmental changes, as well as injury markers. Inhibition of NOS1 does not have any modulating role on VEGF-induced changes in the NB lung. Overall, our data suggests that there is a significant differential regulation in the NOS-mediated effects of VEGF overexpression in the developing mouse lung.

  8. Severe drug-induced repetitive behaviors and striatal overexpression of VAChT in ChAT-ChR2-EYFP BAC transgenic mice

    Directory of Open Access Journals (Sweden)

    Jill R Crittenden

    2014-05-01

    Full Text Available In drug users, drug-related cues alone can induce dopamine release in the dorsal striatum. Instructive cues activate inputs to the striatum from both dopaminergic and cholinergic neurons, which are thought to work together to support motor learning and motivated behaviors. Imbalances in these neuromodulatory influences can impair normal action selection and might thus contribute to pathologically repetitive and compulsive behaviors such as drug addiction. Dopamine and acetylcholine can have either antagonistic or synergistic effects on behavior, depending on the state of the animal and the receptor signaling systems at play. Semi-synchronized activation of cholinergic interneurons in the dorsal striatum drives dopamine release via presynaptic nicotinic acetylcholine receptors located on dopamine terminals. Nicotinic receptor blockade is known to diminish abnormal repetitive behaviors (stereotypies induced by psychomotor stimulants. By contrast, blockade of postsynaptic acetylcholine muscarinic receptors in the dorsomedial striatum exacerbates drug-induced stereotypy, exemplifying how different acetylcholine receptors can also have opposing effects. Although acetylcholine release is known to be altered in animal models of drug addiction, predicting whether these changes will augment or diminish drug-induced behaviors thus remains a challenge. Here, we measured amphetamine-induced stereotypy in BAC transgenic mice that have been shown to overexpress the vesicular acetylcholine transporter (VAChT with consequent increased acetylcholine release. We found that drug-induced stereotypies, consisting of confined sniffing and licking behaviors, were greatly increased in the transgenic mice relative to sibling controls, as was striatal VAChT protein. These findings suggest that VAChT-mediated increases in acetylcholine could be critical in exacerbating drug-induced stereotypic behaviors and promoting exaggerated behavioral fixity.

  9. Severe drug-induced repetitive behaviors and striatal overexpression of VAChT in ChAT-ChR2-EYFP BAC transgenic mice.

    Science.gov (United States)

    Crittenden, Jill R; Lacey, Carolyn J; Lee, Tyrone; Bowden, Hilary A; Graybiel, Ann M

    2014-01-01

    In drug users, drug-related cues alone can induce dopamine release in the dorsal striatum. Instructive cues activate inputs to the striatum from both dopaminergic and cholinergic neurons, which are thought to work together to support motor learning and motivated behaviors. Imbalances in these neuromodulatory influences can impair normal action selection and might thus contribute to pathologically repetitive and compulsive behaviors such as drug addiction. Dopamine and acetylcholine can have either antagonistic or synergistic effects on behavior, depending on the state of the animal and the receptor signaling systems at play. Semi-synchronized activation of cholinergic interneurons in the dorsal striatum drives dopamine release via presynaptic nicotinic acetylcholine receptors located on dopamine terminals. Nicotinic receptor blockade is known to diminish abnormal repetitive behaviors (stereotypies) induced by psychomotor stimulants. By contrast, blockade of postsynaptic acetylcholine muscarinic receptors in the dorsomedial striatum exacerbates drug-induced stereotypy, exemplifying how different acetylcholine receptors can also have opposing effects. Although acetylcholine release is known to be altered in animal models of drug addiction, predicting whether these changes will augment or diminish drug-induced behaviors thus remains a challenge. Here, we measured amphetamine-induced stereotypy in BAC transgenic mice that have been shown to overexpress the vesicular acetylcholine transporter (VAChT) with consequent increased acetylcholine release. We found that drug-induced stereotypies, consisting of confined sniffing and licking behaviors, were greatly increased in the transgenic mice relative to sibling controls, as was striatal VAChT protein. These findings suggest that VAChT-mediated increases in acetylcholine could be critical in exacerbating drug-induced stereotypic behaviors and promoting exaggerated behavioral fixity.

  10. The over-expression of miR-200a in the hypothalamus of ob/ob mice is linked to leptin and insulin signaling impairment.

    Science.gov (United States)

    Crépin, Delphine; Benomar, Yacir; Riffault, Laure; Amine, Hamza; Gertler, Arieh; Taouis, Mohammed

    2014-03-25

    Early in life, leptin plays a crucial role in hypothalamic neural organization. Leptin, most likely, controls neural gene expression conferring then specific phenotype regarding energy homeostasis. MicroRNAs are new regulators for several physiological functions, including the regulation of metabolism. However, the impact of leptin on hypothalamic microRNA patterns remains unknown. Here, we demonstrate that miR-200a, miR-200b and miR-429 are up-regulated in the hypothalamus of genetically obese and leptin deficient ob/ob mice. Leptin treatment down-regulates these miRNAs in ob/ob hypothalamus. The hypothalamic silencing of miR-200a increased the expression level of leptin receptor and insulin receptor substrate 2, reduced body weight gain, and restored liver insulin responsiveness. In addition, the overexpression of pre-miR-200a in a human neuroblastoma cell line impaired insulin and leptin signaling. These findings link the alteration of leptin and insulin signaling to the up-regulation of hypothalamic miR-200a which could be a new target for treatment of obesity. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Inhibition of histone H3K9 acetylation by anacardic acid can correct the over-expression of Gata4 in the hearts of fetal mice exposed to alcohol during pregnancy.

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    Chang Peng

    Full Text Available BACKGROUND: Cardiovascular malformations can be caused by abnormalities in Gata4 expression during fetal development. In a previous study, we demonstrated that ethanol exposure could lead to histone hyperacetylation and Gata4 over-expression in fetal mouse hearts. However, the potential mechanisms of histone hyperacetylation and Gata4 over-expression induced by ethanol remain unclear. METHODS AND RESULTS: Pregnant mice were gavaged with ethanol or saline. Fetal mouse hearts were collected for analysis. The results of ethanol fed groups showed that global HAT activity was unusually high in the hearts of fetal mice while global HDAC activity remained unchanged. Binding of P300, CBP, PCAF, SRC1, but not GCN5, were increased on the Gata4 promoter relative to the saline treated group. Increased acetylation of H3K9 and increased mRNA expression of Gata4, α-MHC, cTnT were observed in these hearts. Treatment with the pan-histone acetylase inhibitor, anacardic acid, reduced the binding of P300, PCAF to the Gata4 promoter and reversed H3K9 hyperacetylation in the presence of ethanol. Interestingly, anacardic acid attenuated over-expression of Gata4, α-MHC and cTnT in fetal mouse hearts exposed to ethanol. CONCLUSIONS: Our results suggest that P300 and PCAF may be critical regulatory factors that mediate Gata4 over-expression induced by ethanol exposure. Alternatively, P300, PCAF and Gata4 may coordinate over-expression of cardiac downstream genes in mouse hearts exposed to ethanol. Anacardic acid may thus protect against ethanol-induced Gata4, α-MHC, cTnT over-expression by inhibiting the binding of P300 and PCAF to the promoter region of these genes.

  12. Hepatic overexpression of idol increases circulating protein convertase subtilisin/kexin type 9 in mice and hamsters via dual mechanisms: sterol regulatory element-binding protein 2 and low-density lipoprotein receptor-dependent pathways.

    Science.gov (United States)

    Sasaki, Makoto; Terao, Yoshio; Ayaori, Makoto; Uto-Kondo, Harumi; Iizuka, Maki; Yogo, Makiko; Hagisawa, Kosuke; Takiguchi, Shunichi; Yakushiji, Emi; Nakaya, Kazuhiro; Ogura, Masatsune; Komatsu, Tomohiro; Ikewaki, Katsunori

    2014-06-01

    Low-density lipoprotein receptor (LDLR) is degraded by inducible degrader of LDLR (Idol) and protein convertase subtilisin/kexin type 9 (PCSK9), thereby regulating circulating LDL levels. However, it remains unclear whether, and if so how, these LDLR degraders affect each other. We therefore investigated effects of liver-specific expression of Idol on LDL/PCSK9 metabolism in mice and hamsters. Injection of adenoviral vector expressing Idol (Ad-Idol) induced a liver-specific reduction in LDLR expression which, in turn, increased very-low-density lipoprotein/LDL cholesterol levels in wild-type mice because of delayed LDL catabolism. Interestingly, hepatic Idol overexpression markedly increased plasma PCSK9 levels. In LDLR-deficient mice, plasma PCSK9 levels were already elevated at baseline and unchanged by Idol overexpression, which was comparable with the observation for Ad-Idol-injected wild-type mice, indicating that Idol-induced PCSK9 elevation depended on LDLR. In wild-type mice, but not in LDLR-deficient mice, Ad-Idol enhanced hepatic PCSK9 expression, with activation of sterol regulatory element-binding protein 2 and subsequently increased expression of its target genes. Supporting in vivo findings, Idol transactivated PCSK9/LDLR in sterol regulatory element-binding protein 2/LDLR-dependent manners in vitro. Furthermore, an in vivo kinetic study using (125)I-labeled PCSK9 revealed delayed clearance of circulating PCSK9, which could be another mechanism. Finally, to extend these findings into cholesteryl ester transfer protein-expressing animals, we repeated the above in vivo experiments in hamsters and obtained similar results. A vicious cycle in LDLR degradation might be generated by PCSK9 induced by hepatic Idol overexpression via dual mechanisms: sterol regulatory element-binding protein 2/LDLR. Furthermore, these effects would be independent of cholesteryl ester transfer protein expression. © 2014 American Heart Association, Inc.

  13. Neuropeptide Y Y1 receptor hippocampal overexpression via viral vectors is associated with modest anxiolytic-like and proconvulsant effects in mice

    DEFF Research Database (Denmark)

    Olesen, Mikkel V; Christiansen, Søren Hofman Oliveira; Gøtzsche, Casper René

    2012-01-01

    -like effect in rodents. The present study explored an alternative and more specific approach: overexpression of Y1 receptors. Using a recombinant adeno-associated viral vector (rAAV) encoding the Y1 gene (rAAV-Y1), we, for the first time, induced overexpression of functional transgene Y1 receptors...

  14. Corticotropin-releasing factor overexpression in mice abrogates sex differences in body weight, visceral fat, and food intake response to a fast and alters levels of feeding regulatory hormones.

    Science.gov (United States)

    Wang, Lixin; Goebel-Stengel, Miriam; Yuan, Pu-Qing; Stengel, Andreas; Taché, Yvette

    2017-01-01

    Corticotropin-releasing factor overexpressing (CRF-OE) male mice showed an inhibited feeding response to a fast, and lower plasma acyl ghrelin and Fos expression in the arcuate nucleus compared to wild-type (WT) mice. We investigated whether hormones and hypothalamic feeding signals are impaired in CRF-OE mice and the influence of sex. Male and female CRF-OE mice and WT littermates (4-6 months old) fed ad libitum or overnight fasted were assessed for body, adrenal glands and perigonadal fat weights, food intake, plasma hormones, blood glucose, and mRNA hypothalamic signals. Under fed conditions, compared to WT, CRF-OE mice have increased adrenal glands and perigonadal fat weight, plasma corticosterone, leptin and insulin, and hypothalamic leptin receptor and decreased plasma acyl ghrelin. Compared to male, female WT mice have lower body and perigonadal fat and plasma leptin but higher adrenal glands weights. CRF-OE mice lost these sex differences except for the adrenals. Male CRF-OE and WT mice did not differ in hypothalamic expression of neuropeptide Y (NPY) and proopiomelanocortin (POMC), while female CRF-OE compared to female WT and male CRF-OE had higher NPY mRNA levels. After fasting, female WT mice lost more body weight and ate more food than male WT, while CRF-OE mice had reduced body weight loss and inhibited food intake without sex difference. In male WT mice, fasting reduced plasma insulin and leptin and increased acyl ghrelin and corticosterone while female WT showed only a rise in corticosterone. In CRF-OE mice, fasting reduced insulin while leptin, acyl ghrelin and corticosterone were unchanged with no sex difference. Fasting blood glucose was higher in CRF-OE with female > male. In WT mice, fasting increased hypothalamic NPY expression in both sexes and decreased POMC only in males, while in CRF-OE mice, NPY did not change, and POMC decreased in males and increased in females. These data indicate that CRF-OE mice have abnormal basal and fasting

  15. Vascular Endothelial Over-Expression of Human Soluble Epoxide Hydrolase (Tie2-sEH Tr Attenuates Coronary Reactive Hyperemia in Mice: Role of Oxylipins and ω-Hydroxylases.

    Directory of Open Access Journals (Sweden)

    Ahmad Hanif

    Full Text Available Cytochromes P450 metabolize arachidonic acid (AA into two vasoactive oxylipins with opposing biologic effects: epoxyeicosatrienoic acids (EETs and omega-(ω-terminal hydroxyeicosatetraenoic acids (HETEs. EETs have numerous beneficial physiological effects, including vasodilation and protection against ischemia/reperfusion injury, whereas ω-terminal HETEs induce vasoconstriction and vascular dysfunction. We evaluated the effect of these oxylipins on post-ischemic vasodilation known as coronary reactive hyperemia (CRH. CRH prevents the potential harm associated with transient ischemia. The beneficial effects of EETs are reduced after their hydrolysis to dihydroxyeicosatrienoic acids (DHETs by soluble epoxide hydrolase (sEH. ω-terminal HETEs are formed by ω-hydroxylase family members. The relationship among endothelial over-expression of sEH (Tie2-sEH Tr, the changes in oxylipins it may produce, the pharmacologic inhibition of ω-hydroxylases, activation of PPARγ, and CRH response to a brief ischemia is not known. We hypothesized that CRH is attenuated in isolated mouse hearts with endothelial sEH over-expression through modulation of oxylipin profiles, whereas both inhibition of ω-hydroxylases and activation of PPARγ enhance CRH. Compared to WT mice, Tie2-sEH Tr mice had decreased CRH, including repayment volume, repayment duration, and repayment/debt ratio (P < 0.05, whereas inhibition of ω-hydroxylases increased these same CRH parameters in Tie2-sEH Tr mice. Inhibition of sEH with t-AUCB reversed the decreased CRH in Tie2-sEH Tr mice. Endothelial over-expression of sEH significantly changed oxylipin profiles, including decreases in DHETs, mid-chain HETEs, and prostaglandins (P < 0.05. Treatment with rosiglitazone, PPARγ-agonist, enhanced CRH (P < 0.05 in both Tie2-sEH Tr and wild type (WT mice. These data demonstrate that endothelial over-expression of sEH (through changing the oxylipin profiles attenuates CRH, whereas inhibition of

  16. Infusion of Trx-1-overexpressing hucMSC prolongs the survival of acutely irradiated NOD/SCID mice by decreasing excessive inflammatory injury.

    Directory of Open Access Journals (Sweden)

    JiangWei Hu

    Full Text Available A protective reagent for ARI should have the ability to repair injured tissue caused by radiation and prevent continuous damage from secondary risk factors. Trx-1 was explored as a candidate therapy for ARI, as it scavenges reactive oxygen species, regulates cell growth and differentiation, participates in immune reactions, and inhibits apoptosis by acting inside and/or outside cells. Trx-1 can also decrease excessive inflammation in ARI by regulating the creation of inflamed media, by inhibiting the activation of complement, and by reducing the chemotaxis, adhesion, and migration of inflammatory cells. As effectively and stably expressing exogenous genes in the long term and regulating immune inflammation and tissue repair, MSC are a good choice for Trx-1 gene therapy. In this study, Trx-1-overexpressing hucMSC-Trx-1 were obtained by adenoviral vector-mediated infection. We first measured the redox capacity of hucMSC-Trx-1 with an antioxidant capacity (T-AOC assay, a hydrogen peroxide (H2O2 content determination assay in vivo, a H2O2-induced oxidation hemolysis assay, and a lipid peroxidation assay in vitro. Then, we measured survival time, the protection of the hematopoietic system, and the regulation of inflammation in important organs in three treatment groups of NOD/SCID mice (treated with hucMSC-Trx-1, with hucMSC, and with saline that were exposed to 4.5 Gy (60Co-γ-ray radiation. The hucMSC-Trx-1 group achieved superior antioxidation results, protecting bone marrow hematopoietic stem cells (Lin(-CD117(+: hucMSC-Trx-1 vs. hucMSC, P<0.05; hucMSC-Trx-1 vs. NS, P<0.01, promoting the formation of red blood cells and hemoglobin (hucMSC-Trx-1 vs. hucMSC or NS, P<0.05, reducing inflammation and damage in important organs (Bone marrow and lung: hucMSC-Trx-1 vs. NS, P<0.01; hucMSC-Trx-1 vs. hucMSC, P<0.05. Liver and intestine: hucMSC-Trx-1 vs. NS, P<0.05; hucMSC-Trx-1 vs. hucMSC, P<0.05, and prolonging survival (hucMSC-Trx-1 vs. hucMSC or NS, P<0

  17. Cell size increased in tissues from transgenic mice overexpressing a cell surface growth-related and cancer-specific hydroquinone oxidase, tNOX, with protein disulfide-thiol interchange activity.

    Science.gov (United States)

    Yagiz, Kader; Snyder, Paul W; Morré, D James; Morré, Dorothy M

    2008-12-15

    tNOX (ENOX2), a cancer-specific and growth-related cell surface protein with protein disulfide-thiol interchange and hydroquinone (NADH) oxidase activities was overexpressed in a transgenic mouse model. Female transgenic mice grew faster than wild type as did embryonic fibroblast cells prepared from the transgenic mice. The tissue expression of tNOX mRNA was greatest in heart, lung and liver. When these tissues were analyzed for cell size, the cells from the tissues of transgenic animals were, on average, 20% larger in surface area than cells from corresponding wild-type tissues. Also analyzed were cells of intestine, spleen and kidney in which tNOX overexpression was observed but to a lesser extent. Cell size was increased as well with intestine and kidney but less so with spleen. At the end of the study, carcass weights of the transgenic animals were greater than those of wild type. This increase in carcass weight was reflected in an increase in femur weight and thickness in both male and female transgenic mice but not in femur length. Other carcass parameters such as skin weight and body fat or body fluids were unchanged or changes were insufficient to account for the increased carcass weight. The findings are consistent with the property of tNOX observed in studies with cultured cells as contributing to the enlargement phase of cell growth.

  18. Phenotype analysis of male transgenic mice overexpressing mutant IGFBP-2 lacking the Cardin-Weintraub sequence motif: Reduced expression of synaptic markers and myelin basic protein in the brain and a lower degree of anxiety-like behaviour.

    Science.gov (United States)

    Schindler, N; Mayer, J; Saenger, S; Gimsa, U; Walz, C; Brenmoehl, J; Ohde, D; Wirthgen, E; Tuchscherer, A; Russo, V C; Frank, M; Kirschstein, T; Metzger, F; Hoeflich, A

    2017-04-01

    Brain growth and function are regulated by insulin-like growth factors I and II (IGF-I and IGF-II) but also by IGF-binding proteins (IGFBPs), including IGFBP-2. In addition to modulating IGF activities, IGFBP-2 interacts with a number of components of the extracellular matrix and cell membrane via a Cardin-Weintraub sequence or heparin binding domain (HBD1). The nature and the signalling elicited by these interactions are not fully understood. Here, we examined transgenic mice (H1d-hBP2) overexpressing a mutant human IGFBP-2 that lacks a specific heparin binding domain (HBD1) known as the Cardin-Weintraub sequence. H1d-hBP2 transgenic mice have the genetic background of FVB mice and are characterized by severe deficits in brain growth throughout their lifetime (pmice, protein levels of the GTPase dynamin-I were significantly reduced (pmice in the cerebellum but not in the hippocampus. At 80weeks of age, weight reductions were similarly present in the cerebellum (-28%; pmice were challenged in the elevated plus maze, aged but not younger H1d-hBP2 mice displayed significantly less anxiety-like behaviour, which was also observed in a second transgenic mouse model overexpressing mouse IGFBP-2 lacking HBD1 (H1d-mBP2). These in vivo studies provide, for the first time, evidence for a specific role of IGFBP-2 in brain functions associated with anxiety and risk behaviour. These activities of IGFBP-2 could be mediated by the Cardin-Weintraub/HBD1 sequence and are altered in mice expressing IGFBP-2 lacking the HBD1. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. TrkB overexpression in mice buffers against memory deficits and depression-like behavior but not all anxiety- and stress-related symptoms induced by developmental exposure to methylmercury

    Directory of Open Access Journals (Sweden)

    Nina N Karpova

    2014-09-01

    Full Text Available Developmental exposure to low dose of methylmercury (MeHg has a long-lasting effect on memory and attention deficits in humans, as well as cognitive performance, depression-like behavior and the hippocampal levels of the brain-derived neurotrophic factor (Bdnfin mice. The Bdnf receptor TrkB is a key player of Bdnf signaling. Using transgenic animals, here we analyzed the effect of the full-length TrkB overexpression (TK+ on behavior impairments induced by perinatal MeHg. TK overexpression in the MeHg-exposed mice enhanced generalized anxiety and cue memory in the fear conditioning test. Early exposure to MeHg induced deficits in reversal spatial memory in the Morris water maze test and depression-like behavior in the forced swim test in only wild-type mice but did not affect these parameters in TK+ mice. These changes were associated with TK+ effect on the increase in Bdnf 2, 3, 4 and 6 transcription in the hippocampus as well as with interaction of TK+ and MeHg factors for Bdnf 1, 9a and truncated TrkB.T1 transcripts in the prefrontal cortex. However, the MeHg-induced anxiety-like behavior in the elevated plus maze and open field tests was ameliorated by TK+ background only in the open field test. Moreover, TK overexpression in the MeHg mice did not prevent significant stress-induced weight loss during the period of adaptation to individual housing in metabolic cages. These TK genotype-independent changes were primarily accompanied by the MeHg-induced hippocampal deficits in the activity-dependent Bdnf 1, 4 and 9a variants, TrkB.T1, and transcripts for important antioxidant enzymes glyoxalases Glo1 and Glo2 and glutathione reductase Gsr. Our data suggest a role of full-length TrkB in buffering against memory deficits and depression-like behavior in the MeHg mice but propose the involvement of additional pathways, such as the antioxidant system or TrkB.T1 signaling, in stress- or anxiety-related responses induced by developmental MeHg exposure.

  20. Over-expression of Stat5b confers protection against diabetes in the non-obese diabetic (NOD) mice via up-regulation of CD4{sup +}CD25{sup +} regulatory T cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Yulan; Purohit, Sharad [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA (United States); Chen, Xueqin; Yi, Bing [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); She, Jin-Xiong, E-mail: jshe@georgiahealth.edu [Center for Biotechnology and Genomic Medicine, Georgia Health Sciences University, GA (United States); Department of Pathology, Medical College of Georgia, Georgia Health Sciences University, GA (United States)

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer This is the first study to provide direct evidence of the role of Stat5b in NOD mice. Black-Right-Pointing-Pointer Over-expression of wild type Stat5b transgene protects NOD mice against diabetes. Black-Right-Pointing-Pointer This protection may be mediated by the up-regulation of CD4{sup +}CD25{sup +} Tregs. -- Abstract: The signal transducers and activators of transcription (STAT) family of proteins play a critical role in cytokine signaling required for fine tuning of immune regulation. Previous reports showed that a mutation (L327M) in the Stat5b protein leads to aberrant cytokine signaling in the NOD mice. To further elaborate the role of Stat5b in diabetes, we established a NOD transgenic mouse that over-expresses the wild type Stat5b gene. The incidences of spontaneous diabetes as well as cyclophosphamide-induced diabetes were significantly reduced and delayed in the Stat5b transgenic NOD mice compared to their littermate controls. The total cell numbers of CD4{sup +} T cells and especially CD8{sup +} T cells in the spleen and pancreatic lymph node were increased in the Stat5b transgenic NOD mice. Consistent with these findings, CD4{sup +} and CD8{sup +} T cells from the Stat5b transgenic NOD mice showed a higher proliferation capacity and up-regulation of multiple cytokines including IL-2, IFN-{gamma}, TNF-{alpha} and IL-10 as well as anti-apoptotic gene Bcl-xl. Furthermore, the number and proportion of CD4{sup +}CD25{sup +} regulatory T cells were significantly increased in transgenic mice although in vitro suppression ability of the regulatory T-cells was not affected by the transgene. Our results suggest that Stat5b confers protection against diabetes in the NOD mice by regulating the numbers and function of multiple immune cell types, especially by up-regulating CD4{sup +}CD25{sup +} regulatory T cells.

  1. Overexpression of apolipoprotein O does not impact on plasma HDL levels or functionality in human apolipoprotein A-I transgenic mice

    NARCIS (Netherlands)

    Nijstad, Niels; de Boer, Jan Freark; Lagor, William R.; Toelle, Markus; Usher, David; Annema, Wijtske; van der Giet, Markus; Rader, Daniel J.; Tietge, Uwe J. F.

    Apolipoprotein (apo) O is a newly discovered apolipoprotein preferentially contained within HDL; however, currently, no data are available on the (patho)physiological effects of apoO. Therefore, the present study assessed the impact of apoO overexpression on (i) plasma lipids and lipoproteins as

  2. Msh homeobox 1 (Msx1)- and Msx2-overexpressing bone marrow-derived mesenchymal stem cells resemble blastema cells and enhance regeneration in mice.

    Science.gov (United States)

    Taghiyar, Leila; Hesaraki, Mahdi; Sayahpour, Forough Azam; Satarian, Leila; Hosseini, Samaneh; Aghdami, Naser; Baghaban Eslaminejad, Mohamadreza

    2017-06-23

    Amputation of the proximal region in mammals is not followed by regeneration because blastema cells (BCs) and expression of regenerative genes, such as Msh homeobox ( Msx ) genes, are absent in this animal group. The lack of BCs and positional information in other cells is therefore the main obstacle to therapeutic approaches for limb regeneration. Hence, this study aimed to create blastema-like cells (BlCs) by overexpressing Msx1 and Msx2 genes in mouse bone marrow-derived mesenchymal stem cells (mBMSCs) to regenerate a proximally amputated digit tip. We transduced mBMSCs with Msx1 and Msx2 genes and compared osteogenic activity and expression levels of several Msx -regulated genes ( Bmp4 , Fgf8 , and keratin 14 ( K14 )) in BlC groups, including MSX1, MSX2, and MSX1/2 (in a 1:1 ratio) with those in mBMSCs and BCs in vitro and in vivo following injection into the amputation site. We found that Msx gene overexpression increased expression of specific blastemal markers and enhanced the proliferation rate and osteogenesis of BlCs compared with mBMSCs and BCs via activation of Fgf8 and Bmp4 Histological analyses indicated full regrowth of digit tips in the Msx -overexpressing groups, particularly in MSX1/2, through endochondral ossification 6 weeks post-injection. In contrast, mBMSCs and BCs formed abnormal bone and nail. Full digit tip was regenerated only in the MSX1/2 group and was related to boosted Bmp4, Fgf8 , and K14 gene expression and to limb-patterning properties resulting from Msx1 and Msx2 overexpression. We propose that Msx -transduced cells that can regenerate epithelial and mesenchymal tissues may potentially be utilized in limb regeneration. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Reduced Self-Diploidization and Improved Survival of Semi-cloned Mice Produced from Androgenetic Haploid Embryonic Stem Cells through Overexpression of Dnmt3b

    Directory of Open Access Journals (Sweden)

    Wenteng He

    2018-02-01

    Full Text Available Summary: Androgenetic haploid embryonic stem cells (AG-haESCs hold great promise for exploring gene functions and generating gene-edited semi-cloned (SC mice. However, the high incidence of self-diploidization and low efficiency of SC mouse production are major obstacles preventing widespread use of these cells. Moreover, although SC mice generation could be greatly improved by knocking out the differentially methylated regions of two imprinted genes, 50% of the SC mice did not survive into adulthood. Here, we found that the genome-wide DNA methylation level in AG-haESCs is extremely low. Subsequently, downregulation of both de novo methyltransferase Dnmt3b and other methylation-related genes was determined to be responsible for DNA hypomethylation. We further demonstrated that ectopic expression of Dnmt3b in AG-haESCs could effectively improve DNA methylation level, and the high incidence of self-diploidization could be markedly rescued. More importantly, the developmental potential of SC embryos was improved, and most SC mice could survive into adulthood. : Ectopic expression of Dnmt3b could rescue DNA methylation level in repetitive sequences of hypomethylated AG-haESCs, suppress high incidence of self-diploidization, and promote developmental potential of SC embryos, and most SC mice could survive into adulthood. Keywords: androgenetic haploid embryonic stem cells, self-diploidization, semi-cloned mice, DNA methylation, Dnmt3b

  4. EBI2 overexpression in mice leads to B1 B cell expansion and chronic lymphocytic leukemia-(CLL)-like B cell malignancies

    DEFF Research Database (Denmark)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau

    2017-01-01

    Human and mouse chronic lymphocytic leukemia (CLL) develop from CD5+ B cells that in mice and macaques are known to define the distinct B1a B cell lineage. B1a cells are characterized by lack of germinal center development and the B1a cell population is increased in mice with reduced germinal...... center formation. As a major mediator of follicular B cell migration, the G protein-coupled receptor (GPCR) Epstein Barr virus-induced gene 2 (EBI2 or GPR183) directs B cell migration in the lymphoid follicles in response to its endogenous ligands, oxysterols. Thus, upregulation of EBI2 drives the B...

  5. Gender-specific effects on food intake but no inhibition of age-related fat accretion in transgenic mice overexpressing human IGFBP-2 lacking the Cardin-Weintraub sequence motif.

    Science.gov (United States)

    Wiedmer, Petra; Schwarz, Franziska; Große, Birgit; Schindler, Nancy; Tuchscherer, Armin; Russo, Vincenzo C; Tschöp, Matthias H; Hoeflich, Andreas

    2015-06-01

    IGFBP-2 affects growth and metabolism and is thought to impact on energy homeostasis and the accretion of body fat via its heparin binding domains (HBD). In order to assess the function of the HBD present in the linker domain (HBD1) we have generated transgenic mice overexpressing mutant human IGFBP-2 lacking the PKKLRP sequence and carrying a PNNLAP sequence instead. Transgenic mice expressed high amounts of human IGFBP-2, while endogenous IGFBP-2 or IGF-I serum concentrations were not affected. In both genders we performed a longitudinal analysis of growth and metabolism including at least 4 separate time points between the age of 10 and 52 weeks. Body composition was assessed by nuclear magnetic resonance (NMR) analysis. Food intake was recorded by an automated online-monitoring. We describe negative effects of mutant human IGFBP-2 on body weight, longitudinal growth and lean body mass (p transgenic mice of both genders (p transgene expression significantly increased absolute mass of total body fat over all age groups (p Food intake was increased in female but decreased in male transgenic mice at an age of 11 weeks. Thus our study clearly provides gender- and time-specific effects of HBD1-deficient hIGFBP-2 (H1d-BP-2) on fat mass accretion and food intake. While our data are in principal agreement with current knowledge on the role of HB-domains for fat accretion we now may also speculate on a role of HBD1 for the control of eating behavior.

  6. Oral administration of Aloe vera gel powder prevents UVB-induced decrease in skin elasticity via suppression of overexpression of MMPs in hairless mice.

    Science.gov (United States)

    Saito, Marie; Tanaka, Miyuki; Misawa, Eriko; Yao, Ruiquing; Nabeshima, Kazumi; Yamauchi, Kouji; Abe, Fumiaki; Yamamoto, Yuki; Furukawa, Fukumi

    2016-07-01

    This study reports the effects of oral Aloe vera gel powder (AVGP) containing Aloe sterols on skin elasticity and the extracellular matrix in ultraviolet B (UVB)-irradiated hairless mice. Ten-week-old hairless mice were fed diets containing 0.3% AVGP for 8 weeks and irradiated UVB for 6 weeks. Mice treated with AVGP showed significant prevention of the UVB-induced decrease in skin elasticity. To investigate the mechanism underlying this suppression of skin elasticity loss, we measured the expression of matrix metalloproteinase (MMP)-2, -9, and -13. AVGP prevented both the UVB-induced increases in MMPs expressions. Moreover, we investigated hyaluronic acid (HA) content of mice dorsal skin and gene expression of HA synthase-2 (Has2). In the results, AVGP oral administration prevented UVB-induced decreasing in skin HA content and Has2 expression and attenuates the UVB-induced decrease in serum adiponectin, which promotes Has2 expression. These results suggested that AVGP has the ability to prevent the skin photoaging.

  7. Y5 neuropeptide Y receptor overexpression in mice neither affects anxiety- and depression-like behaviours nor seizures but confers moderate hyperactivity

    DEFF Research Database (Denmark)

    Olesen, Mikkel V; Christiansen, Søren Hofman Oliveira; Gøtzsche, Casper René

    2012-01-01

    , by testing effects of recombinant adeno-associated viral vector (rAAV) encoding Y5 (rAAV-Y5) in anxiety- and depression-like behaviour as well as in kainate-induced seizures in adult mice. The rAAV-Y5 vector injected into the hippocampus and amygdala induced a pronounced and sustained increase in Y5 receptor...

  8. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Soderman, A.; Spang-Thomsen, Mogens; Hansen, H.

    2008-01-01

    through the use of co-immunoprecipitation that human Abeta-immunoreactive peptides bind to mice alpha7 nAChR in vivo. Agonists of the alpha7 nAChR improve memory and attentional properties and increase immediate early gene expression in the prefrontal cortex and the nucleus accumbens. We show that acute...

  9. Plaque deposition dependent decrease in 5-HT2A serotonin receptor in AbetaPPswe/PS1dE9 amyloid overexpressing mice

    DEFF Research Database (Denmark)

    Holm, Peter; Ettrup, Anders; Klein, Anders B

    2010-01-01

    -HT2A receptor regulation in double transgenic AbetaPPswe/PS1dE9 mice which display excess production of Abeta and age-dependent increase in amyloid plaques. Three different age-groups, 4-month-old, 8- month-old, and 11-month-old were included in the study. [3H]-MDL100907, [3H]-escitalopram, and [11C...

  10. Overexpression of Notch ligand Delta-like-1 by dendritic cells enhances their immunoregulatory capacity and exerts antiallergic effects on Th2-mediated allergic asthma in mice.

    Science.gov (United States)

    Lee, Chen-Chen; Lin, Chu-Lun; Leu, Sy-Jye; Lee, Yueh-Lun

    2018-02-01

    Dendritic cells (DCs) are professional antigen-presenting cells, and Notch ligand Delta-like-1 (DLL1) on DCs was implicated in type 1T helper (Th1) differentiation. In this study, we produced genetically engineered bone marrow-derived DCs that expressed DLL1 (DLL1-DCs) by adenoviral transduction. DLL1-DCs exerted a fully mature phenotype, and had positive effects on expression levels of interleukin (IL)-12 and costimulatory molecules. Coculture of allogeneic T cells with ovalbumin (OVA)-pulsed DLL1-DCs enhanced T cell proliferative responses and promoted Th1 cell differentiation. Furthermore, adoptive transfer of OVA-stimulated DLL1-DCs into asthmatic mice alleviated the cardinal features of allergic asthma, including immunoglobulin E (IgE) production, airway hyperresponsiveness (AHR), airway inflammation, and production of Th2-type cytokines. Notably, enhanced levels of the Th1-biased IgG 2a response and interferon (IFN)-γ production were observed in these mice. Taken together, these data indicate that DLL1-DCs promoted Th1 cell development to alter the Th1/Th2 ratio and ameliorate Th2-mediated allergic asthma in mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Early and rapid development of insulin resistance, islet dysfunction and glucose intolerance after high-fat feeding in mice overexpressing phosphodiesterase 3B

    DEFF Research Database (Denmark)

    Walz, Helena A; Härndahl, Linda; Wierup, Nils

    2006-01-01

    advanced fasting hyperinsulinemia and early development of hyper-glycemia, in spite of hyperinsulinemia, as well as impaired capacity of insulin to suppress plasma glucose in an insulin tolerance test. In vitro analyses of insulin-stimulated lipogenesis in adipocytes and glucose uptake in skeletal muscle......AMP-degrading enzyme phosphodiesterase 3B (RIP-PDE3B/2 mice) were metabolically challenged with a high-fat diet. We found that RIP-PDE3B/2 mice early and rapidly develop glucose intolerance and insulin resistance, as compared with wild-type littermates, after 2 months of high-fat feeding. This was evident from...... perturbations, such as centrally located alpha-cells and reduced immunostaining for insulin and GLUT2 in islets from RIP-PDE3B/2 mice. Additionally, in vitro experiments revealed that the insulin secretory response to glucagon-like peptide-1 stimulation was markedly reduced in islets from high-fat-fed RIP-PDE3B...

  12. Human hepatic lipase overexpression in mice induces hepatic steatosis and obesity through promoting hepatic lipogenesis and white adipose tissue lipolysis and fatty acid uptake.

    Directory of Open Access Journals (Sweden)

    Lídia Cedó

    Full Text Available Human hepatic lipase (hHL is mainly localized on the hepatocyte cell surface where it hydrolyzes lipids from remnant lipoproteins and high density lipoproteins and promotes their hepatic selective uptake. Furthermore, hepatic lipase (HL is closely associated with obesity in multiple studies. Therefore, HL may play a key role on lipid homeostasis in liver and white adipose tissue (WAT. In the present study, we aimed to evaluate the effects of hHL expression on hepatic and white adipose triglyceride metabolism in vivo. Experiments were carried out in hHL transgenic and wild-type mice fed a Western-type diet. Triglyceride metabolism studies included β-oxidation and de novo lipogenesis in liver and WAT, hepatic triglyceride secretion, and adipose lipoprotein lipase (LPL-mediated free fatty acid (FFA lipolysis and influx. The expression of hHL promoted hepatic triglyceride accumulation and de novo lipogenesis without affecting triglyceride secretion, and this was associated with an upregulation of Srebf1 as well as the main genes controlling the synthesis of fatty acids. Transgenic mice also exhibited more adiposity and an increased LPL-mediated FFA influx into the WAT without affecting glucose tolerance. Our results demonstrate that hHL promoted hepatic steatosis in mice mainly by upregulating de novo lipogenesis. HL also upregulated WAT LPL and promoted triglyceride-rich lipoprotein hydrolysis and adipose FFA uptake. These data support the important role of hHL in regulating hepatic lipid homeostasis and confirm the broad cardiometabolic role of HL.

  13. A Conditioned Medium of Umbilical Cord Mesenchymal Stem Cells Overexpressing Wnt7a Promotes Wound Repair and Regeneration of Hair Follicles in Mice

    Directory of Open Access Journals (Sweden)

    Liang Dong

    2017-01-01

    Full Text Available Mesenchymal stem cells (MSCs can affect the microenvironment of a wound and thereby accelerate wound healing. Wnt proteins act as key mediators of skin development and participate in the formation of skin appendages such as hair. The mechanisms of action of MSCs and Wnt proteins on skin wounds are largely unknown. Here, we prepared a Wnt7a-containing conditioned medium (Wnt-CM from the supernatant of cultured human umbilical cord-MSCs (UC-MSCs overexpressing Wnt7a in order to examine the effects of this CM on cutaneous healing. Our results revealed that Wnt-CM can accelerate wound closure and induce regeneration of hair follicles. Meanwhile, Wnt-CM enhanced expression of extracellular matrix (ECM components and cell migration of fibroblasts but inhibited the migratory ability and expression of K6 and K16 in keratinocytes by enhancing expression of c-Myc. However, we found that the CM of fibroblasts treated with Wnt-CM (HFWnt-CM-CM can also promote wound repair and keratinocyte migration; but there was no increase in the number of hair follicles of regeneration. These data indicate that Wnt7a and UC-MSCs have synergistic effects: they can accelerate wound repair and induce hair regeneration via cellular communication in the wound microenvironment. Thus, this study opens up new avenues of research on the mechanisms underlying wound repair.

  14. Defective vascular development in connexin 45-deficient mice

    NARCIS (Netherlands)

    Krüger, O.; Plum, A.; Kim, J. S.; Winterhager, E.; Maxeiner, S.; Hallas, G.; Kirchhoff, S.; Traub, O.; Lamers, W. H.; Willecke, K.

    2000-01-01

    In order to reveal the biological function(s) of the gap-junction protein connexin 45 (Cx45), we generated Cx45-deficient mice with targeted replacement of the Cx45-coding region with the lacZ reporter gene. Heterozygous Cx45(+/)(-) mice showed strong expression of the reporter gene in vascular and

  15. Plaque deposition dependent decrease in 5-HT2A serotonin receptor in AbetaPPswe/PS1dE9 amyloid overexpressing mice.

    Science.gov (United States)

    Holm, Peter; Ettrup, Anders; Klein, Anders B; Santini, Martin A; El-Sayed, Mona; Elvang, Anders B; Stensbøl, Tine B; Mikkelsen, Jens D; Knudsen, Gitte M; Aznar, Susana

    2010-01-01

    Intrahippocampal injections of aggregated amyloid-beta (Abeta)1-42 in rats result in memory impairment and in reduction of hippocampal 5-HT2A receptor levels. In order to investigate how changes in 5-HT2A levels and functionality relate to the progressive accumulation of Abeta protein, we studied 5-HT2A receptor regulation in double transgenic AbetaPPswe/PS1dE9 mice which display excess production of Abeta and age-dependent increase in amyloid plaques. Three different age-groups, 4-month-old, 8- month-old, and 11-month-old were included in the study. [3H]-MDL100907, [3H]-escitalopram, and [11C]-PIB autoradiography was performed for measuring 5-HT2A receptor, serotonin transporter (SERT), and Abeta plaque levels in medial prefrontal cortex (mPFC), prefrontal cortex (PFC), frontoparietal cortex (FPC), dorsal and ventral hippocampus, and somatosensory cortex. To investigate 5-HT2A receptor functionality, animals were treated with the 5-HT2A receptor agonist DOI and head-twitch response (HTR) subsequently recorded. Expression level of the immediate early gene c-fos was measured by in situ hybridization. We found that the age-related increase in Abeta plaque burden was accompanied by a significant decrease in 5-HT2A receptor binding in mPFC in the 11-month-old group. The changes in 5-HT2A receptor binding correlated negatively with [11C]-PIB binding and were not accompanied by decreases in SERT binding. Correspondingly, 11-month-old transgenic mice showed diminished DOI-induced HTR and reduced increase in expression of c-fos mRNA in mPFC and FPC. These observations point towards a direct association between Abeta accumulation and changes in 5-HT2A receptor expression that is independent of upstream changes in the serotonergic system.

  16. Overexpression of Interleukin-4 in the Thyroid of Transgenic Mice Upregulates the Expression of Duox1 and the Anion Transporter Pendrin.

    Science.gov (United States)

    Eskalli, Zineb; Achouri, Younes; Hahn, Stephan; Many, Marie-Christine; Craps, Julie; Refetoff, Samuel; Liao, Xiao-Hui; Dumont, Jacques E; Van Sande, Jacqueline; Corvilain, Bernard; Miot, Françoise; De Deken, Xavier

    2016-10-01

    The dual oxidases (Duox) are involved in hydrogen peroxide generation, which is essential for thyroid hormone synthesis, and therefore they are markers of thyroid function. During inflammation, cytokines upregulate DUOX gene expression in the airway and the intestine, suggesting a role for these proteins in innate immunity. It was previously demonstrated that interleukin-4 (IL-4) upregulates DUOX gene expression in thyrocytes. Although the role of IL-4 in autoimmune thyroid diseases has been studied extensively, the effects of IL-4 on thyroid physiology remain largely unknown. Therefore, a new animal model was generated to study the impact of IL-4 on thyroid function. Transgenic (Thyr-IL-4) mice with thyroid-targeted expression of murine IL-4 were generated. Transgene expression was verified at the mRNA and protein level in thyroid tissues and primary cultures. The phenotype of the Thyr-IL-4 animals was characterized by measuring serum thyroxine (T4) and thyrotropin levels and performing thyroid morphometric analysis, immunohistochemistry, whole transcriptome sequencing, quantitative reverse transcription polymerase chain reaction, and ex vivo thyroid function assays. Thyrocytes from two Thyr-IL-4 mouse lines (#30 and #52) expressed IL-4, which was secreted into the extracellular space. Although 10-month-old transgenic animals had T4 and thyrotropin serum levels in the normal range, they had altered thyroid follicular structure with enlarged follicles composed of elongated thyrocytes containing numerous endocytic vesicles. These follicles were positive for T4 staining the colloid, indicating their capacity to produce thyroid hormones. RNA profiling of Thyr-IL-4 thyroid samples revealed modulation of multiple genes involved in inflammation, while no major leukocyte infiltration could be detected. Upregulated expression of Duox1, Duoxa1, and the pendrin anion exchanger gene (Slc26a4) was detected. In contrast, the iodide symporter gene Slc5a5 was markedly

  17. Simultaneous detection of changes in protein expression and oxidative modification as function of age and APOE genotype in human APOE-targeted replacement mice

    Science.gov (United States)

    Background The purpose of this study was to improve the current method for detecting differentially-oxidized (carbonyl-modified) proteins by 2D-DIGE, while at the same time determining changes in total protein expression. Protein oxidation is a widely accepted model of aging and...

  18. Decreased proliferation kinetics of mouse myoblasts overexpressing FRG1.

    Directory of Open Access Journals (Sweden)

    Steven C Chen

    Full Text Available Although recent publications have linked the molecular events driving facioscapulohumeral muscular dystrophy (FSHD to expression of the double homeobox transcription factor DUX4, overexpression of FRG1 has been proposed as one alternative causal agent as mice overexpressing FRG1 present with muscular dystrophy. Here, we characterize proliferative defects in two independent myoblast lines overexpressing FRG1. Myoblasts isolated from thigh muscle of FRG1 transgenic mice, an affected dystrophic muscle, exhibit delayed proliferation as measured by decreased clone size, whereas myoblasts isolated from the unaffected diaphragm muscle proliferated normally. To confirm the observation that overexpression of FRG1 could impair myoblast proliferation, we examined C2C12 myoblasts with inducible overexpression of FRG1, finding increased doubling time and G1-phase cells in mass culture after induction of FRG1 and decreased levels of pRb phosphorylation. We propose that depressed myoblast proliferation may contribute to the pathology of mice overexpressing FRG1 and may play a part in FSHD.

  19. Quantitative nature of overexpression experiments

    Science.gov (United States)

    Moriya, Hisao

    2015-01-01

    Overexpression experiments are sometimes considered as qualitative experiments designed to identify novel proteins and study their function. However, in order to draw conclusions regarding protein overexpression through association analyses using large-scale biological data sets, we need to recognize the quantitative nature of overexpression experiments. Here I discuss the quantitative features of two different types of overexpression experiment: absolute and relative. I also introduce the four primary mechanisms involved in growth defects caused by protein overexpression: resource overload, stoichiometric imbalance, promiscuous interactions, and pathway modulation associated with the degree of overexpression. PMID:26543202

  20. Overexpression of cellular glutathione peroxidase rescues homocyst(e)ine-induced endothelial dysfunction

    Science.gov (United States)

    Weiss, Norbert; Zhang, Ying-Yi; Heydrick, Stanley; Bierl, Charlene; Loscalzo, Joseph

    2001-01-01

    Homocyst(e)ine (Hcy) inhibits the expression of the antioxidant enzyme cellular glutathione peroxidase (GPx-1) in vitro and in vivo, which can lead to an increase in reactive oxygen species that inactivate NO and promote endothelial dysfunction. In this study, we tested the hypothesis that overexpression of GPx-1 can restore the normal endothelial phenotype in hyperhomocyst(e)inemic states. Heterozygous cystathionine β-synthase-deficient (CBS(−/+)) mice and their wild-type littermates (CBS(+/+)) were crossbred with mice that overexpress GPx-1 [GPx-1(tg+) mice]. GPx-1 activity was 28% lower in CBS(−/+)/GPx-1(tg−) compared with CBS(+/+)/GPx-1(tg−) mice (P < 0.05), and CBS(−/+) and CBS(+/+) mice overexpressing GPx-1 had 1.5-fold higher GPx-1 activity compared with GPx-1 nontransgenic mice (P < 0.05). Mesenteric arterioles of CBS(−/+)/GPx-1(tg−) mice showed vasoconstriction to superfusion with β-methacholine and bradykinin (P < 0.001 vs. all other groups), whereas nonhyperhomocyst(e)inemic mice [CBS(+/+)/GPx-1(tg−) and CBS(+/+)/GPx-1(tg+) mice] demonstrated dose-dependent vasodilation in response to both agonists. Overexpression of GPx-1 in hyperhomocyst(e)inemic mice restored the normal endothelium-dependent vasodilator response. Bovine aortic endothelial cells (BAEC) were transiently transfected with GPx-1 and incubated with dl-homocysteine (HcyH) or l-cysteine. HcyH incubation decreased GPx-1 activity in sham-transfected BAEC (P < 0.005) but not in GPx-1-transfected cells. Nitric oxide release from BAEC was significantly decreased by HcyH but not cysteine, and GPx-1 overexpression attenuated this decrease. These findings demonstrate that overexpression of GPx-1 can compensate for the adverse effects of Hcy on endothelial function and suggest that the adverse vascular effects of Hcy are at least partly mediated by oxidative inactivation of NO. PMID:11606774

  1. Autotaxin overexpression causes embryonic lethality and vascular defects.

    Directory of Open Access Journals (Sweden)

    Hiroshi Yukiura

    Full Text Available Autotaxin (ATX is a secretory protein, which converts lysophospholipids to lysophosphatidic acid (LPA, and is essential for embryonic vascular formation. ATX is abundantly detected in various biological fluids and its level is elevated in some pathophysiological conditions. However, the roles of elevated ATX levels remain to be elucidated. In this study, we generated conditional transgenic (Tg mice overexpressing ATX and examined the effects of excess LPA signalling. We found that ATX overexpression in the embryonic period caused severe vascular defects and was lethal around E9.5. ATX was conditionally overexpressed in the neonatal period using the Cre/loxP system, which resulted in a marked increase in the plasma LPA level. This resulted in retinal vascular defects including abnormal vascular plexus and increased vascular regression. Our findings indicate that the ATX level must be carefully regulated to ensure coordinated vascular formation.

  2. Autotaxin Overexpression Causes Embryonic Lethality and Vascular Defects

    Science.gov (United States)

    Yukiura, Hiroshi; Kano, Kuniyuki; Kise, Ryoji; Inoue, Asuka; Aoki, Junken

    2015-01-01

    Autotaxin (ATX) is a secretory protein, which converts lysophospholipids to lysophosphatidic acid (LPA), and is essential for embryonic vascular formation. ATX is abundantly detected in various biological fluids and its level is elevated in some pathophysiological conditions. However, the roles of elevated ATX levels remain to be elucidated. In this study, we generated conditional transgenic (Tg) mice overexpressing ATX and examined the effects of excess LPA signalling. We found that ATX overexpression in the embryonic period caused severe vascular defects and was lethal around E9.5. ATX was conditionally overexpressed in the neonatal period using the Cre/loxP system, which resulted in a marked increase in the plasma LPA level. This resulted in retinal vascular defects including abnormal vascular plexus and increased vascular regression. Our findings indicate that the ATX level must be carefully regulated to ensure coordinated vascular formation PMID:25992708

  3. Cyclin D1 overexpression increases susceptibility to 4-nitroquinoline 1-oxide induced dysplasia and neoplasia in murine squamous oral epithelium

    Science.gov (United States)

    Wilkey, Jonathan F.; Buchberger, Glenn; Saucier, Kirsten; Patel, Salony M.; Eisenberg, Ellen; Nakagawa, Hiroshi; Michaylira, Carmen; Rustgi, Anil K.; Mallya, Sanjay M.

    2009-01-01

    The cyclin D1 oncogene is frequently amplified/overexpressed in oral squamous cell carcinomas. Mice with overexpression of cyclin D1 targeted to the stratified squamous epithelia of the tongue, esophagus and forestomach develop a phenotype of epithelial dysplasia at these sites. In this study, we examined the effect cyclin D1 overexpression on susceptibility of mice to carcinogen-induced tumorigenesis, using 4-nitroquinoline-1-oxide (4NQO), an established potent oral carcinogen in mice. Cyclin D1 overexpressing mice and non-transgenic littermates were administered 4NQO (20 ppm or 50 ppm in the drinking water) for 8 weeks and monitored for an additional 16 weeks. Histopathological analyses of the tongue revealed significantly higher severity of dysplasia in the cyclin D1 overexpression mice, compared with non-transgenic controls and with untreated controls. Moreover, only the cyclin D1 overexpression mice developed neoplastic lesions in the oro-esophageal epithelia. Examination of the dysplastic and neoplastic lesions reveled abnormal proliferation. Our findings suggest that cyclin D1 overexpression enhances susceptibility to carcinogen-induced oral tumorigenesis. These results underscore the importance of cyclin D1 in the process of oral neoplastic development. Further, they emphasize the value of this transgenic model to study the pathogenesis of oral precancer and cancer and establish it as a model system to test candidate agents for chemoprevention of upper aero-digestive cancer. PMID:19263437

  4. Enhanced Androgen Signaling With Androgen Receptor Overexpression in the Osteoblast Lineage Controls Skeletal Turnover, Matrix Quality and Bone Architecture

    National Research Council Canada - National Science Library

    Wiren, Kristine M; Jepsen, Karl

    2006-01-01

    .... We genetically engineered transgenic mice in which androgen receptor (AR) overexpression is skeletally targeted in two separate models to better understand the role of androgen signaling directly in bone...

  5. Effects of HSP90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) on NEU/HER2 overexpressing mammary tumours in MMTV-NEU-NT mice monitored by Magnetic Resonance Spectroscopy.

    Science.gov (United States)

    Rodrigues, Loreta M; Chung, Yuen-Li; Al Saffar, Nada M S; Sharp, Swee Y; Jackson, Laura E; Banerji, Udai; Stubbs, Marion; Leach, Martin O; Griffiths, John R; Workman, Paul

    2012-05-23

    The importance of ERBB2/NEU/HER2 in the response of breast tumours to the heat shock protein 90 (HSP90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG; tanespimycin) has been demonstrated in the clinic. ERBB2 is an oncoprotein client that is highly dependent on HSP90. This and other oncogenic client proteins (e.g. B-RAF, C-RAF, ALK and CDK4) are depleted by 17-AAG in both animal tumours and patients. Here we investigate by Magnetic Resonance Spectroscopy (MRS) the metabolic response of 17-AAG in spontaneous, NEU/HER2 driven mammary tumours in transgenic MMTV-NEU-NT mice and in cells isolated and cultured from these tumours. Mammary tumours were monitored by 31P MRS in vivo and in tumour extracts, comparing control and 17-AAG treated mice. A cell line derived from NEU/HER2 mammary tumours was also cultured and the effect of 17-AAG was measured by 31P MRS in cell extracts. Molecular biomarkers were assessed by immunoblotting in extracts from cells and tumours. For comparison of tumour volume, metabolite concentrations and Western blot band intensities, two-tailed unpaired t-tests were used. The NEU/HER2 mammary tumours were very sensitive to 17-AAG and responded in a dose-dependent manner to 3 daily doses of 20, 40 and 80mg/kg of 17-AAG, all of which caused significant regression. At the higher doses, 31P MRS of tumour extracts showed significant decreases in phosphocholine (PC) and phosphoethanolamine (PE) whereas no significant changes were seen at the 20mg/kg dose. Extracts of isolated cells cultured from the mammary carcinomas showed a significant decrease in viable cell number and total PME after 17-AAG treatment. Western blots confirmed the expected action of 17-AAG in inducing HSP72 and significantly depleting HSP90 client proteins, including NEU/HER2 both in tumours and in isolated cells. The data demonstrate the high degree of sensitivity of this clinically relevant NEU/HER2-driven tumour model to HSP90 inhibition by 17-AAG, consistent with the

  6. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

    Directory of Open Access Journals (Sweden)

    Chunxiang Yao

    Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  7. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

    Science.gov (United States)

    Yao, Chunxiang; Behring, Jessica B; Shao, Di; Sverdlov, Aaron L; Whelan, Stephen A; Elezaby, Aly; Yin, Xiaoyan; Siwik, Deborah A; Seta, Francesca; Costello, Catherine E; Cohen, Richard A; Matsui, Reiko; Colucci, Wilson S; McComb, Mark E; Bachschmid, Markus M

    2015-01-01

    Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2), react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat), an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT) labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg) mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  8. Kindling-induced overexpression of Homer 1A and its functional implications for epileptogenesis.

    Science.gov (United States)

    Potschka, H; Krupp, E; Ebert, U; Gümbel, C; Leichtlein, C; Lorch, B; Pickert, A; Kramps, S; Young, K; Grüne, U; Keller, A; Welschof, M; Vogt, G; Xiao, B; Worley, P F; Löscher, W; Hiemisch, H

    2002-12-01

    Despite an extensive research on the molecular basis of epilepsy, the essential players in the epileptogenic process leading to epilepsy are not known. Gene expression analysis is one strategy to enhance our understanding of the genes contributing to the functional neuronal changes underlying epileptogenesis. In the present study, we used the novel MPSS (massively parallel signature sequencing) method for analysis of gene expression in the rat kindling model of temporal lobe epilepsy. Kindling by repeated electrical stimulation of the amygdala resulted in the differential expression of 264 genes in the hippocampus compared to sham controls. The most strongly induced gene was Homer 1A, an immediate early gene involved in the modulation of glutamate receptor function. The overexpression of Homer 1A in the hippocampus of kindled rats was confirmed by RT-PCR. In order to evaluate the functional implications of Homer 1A overexpression for kindling, we used transgenic mice that permanently overexpress Homer 1A. Immunohistochemical characterization of these mice showed a marked Homer 1A overexpression in glutamatergic neurons of the hippocampus. Kindling of Homer 1A overexpressing mice resulted in a retardation of seizure generalization compared to wild-type controls. The data demonstrate that kindling-induced epileptogenesis leads to a striking overexpression of Homer 1A in the hippocampus, which may represent an intrinsic antiepileptogenic and anticonvulsant mechanism in the course of epileptogenesis that counteracts progression of the disease.

  9. Overexpression of SK2 channels enhances efferent suppression of cochlear responses without enhancing noise resistance.

    Science.gov (United States)

    Maison, Stéphane F; Parker, Lisan L; Young, Lucy; Adelman, John P; Zuo, Jian; Liberman, M Charles

    2007-04-01

    Cochlear hair cells express SK2, a small-conductance Ca(2+)-activated K(+) channel thought to act in concert with Ca(2+)-permeable nicotinic acetylcholine receptors (nAChRs) alpha9 and alpha10 in mediating suppressive effects of the olivocochlear efferent innervation. To probe the in vivo role of SK2 channels in hearing, we examined gene expression, cochlear function, efferent suppression, and noise vulnerability in mice overexpressing SK2 channels. Cochlear thresholds, as measured by auditory brain stem responses and otoacoustic emissions, were normal in overexpressers as was overall cochlear morphology and the size, number, and distribution of efferent terminals on outer hair cells. Cochlear expression levels of SK2 channels were elevated eightfold without striking changes in other SK channels or in the alpha9/alpha10 nAChRs. Shock-evoked efferent suppression of cochlear responses was significantly enhanced in overexpresser mice as seen previously in alpha9 overexpresser mice; however, in contrast to alpha9 overexpressers, SK2 overexpressers were not protected from acoustic injury. Results suggest that efferent-mediated cochlear protection is mediated by other downstream effects of ACh-mediated Ca(2+) entry different from those involving SK2-mediated hyperpolarization and the associated reduction in outer hair cell electromotility.

  10. Transient overexpression of the 5-HT1A receptor impairs water-maze but not hole-board performance.

    Science.gov (United States)

    Bert, B; Dere, E; Wilhelmi, N; Kusserow, H; Theuring, F; Huston, J P; Fink, H

    2005-07-01

    Previously, we showed that mice that overexpress the 5-HT(1A) receptor transiently from embryonic to perinatal stages show reduced anxiety and changes in brain serotonin turnover as adults. Here, we investigated the long-term effects of the temporary overexpression of the 5-HT(1A) receptor during early embryonic and perinatal development on the performance in two memory tasks. In the hole-board test mice that were homozygous for the transgene showed similar behavioral habituation but increased locomotion compared to heterozygous mice. In contrast water-maze performance of homozygous mice was impaired compared to heterozygous mice. These results suggest that a transient overexpression of 5-HT(1A) receptor during embryonic and perinatal development has detrimental effects on water-maze performance at adult stages.

  11. Effects of gene F10 over-expression on the tumorigenicity of A549 cells

    OpenAIRE

    Ya-li SONG; Gong ZHANG; Zhan-jun PANG; Xiu-lan ZHU; Xiao-ping YANG; Ya-fang LI; Song QUAN; Fu-qi XING

    2012-01-01

    Objective To explore the effects and mechanism of gene F10 over-expression on the tumorigenicity of A549 cells in nude mice. Methods Eighteen SPF nude mice (4-5weeks of age) were randomly equally divided into the three groups: A549-WT (vaccination with wild-type strain A549), Mock-A549 (vaccination with controlled cells Mock-A549 transfected by blank vectors) and F10+A549 (vaccination with F10+A549 cells which overexpressed F10 gene) according to their vaccination and then revaccinated into t...

  12. GNB3 overexpression causes obesity and metabolic syndrome.

    Science.gov (United States)

    Ozdemir, Alev Cagla; Wynn, Grace M; Vester, Aimee; Weitzmann, M Neale; Neigh, Gretchen N; Srinivasan, Shanthi; Rudd, M Katharine

    2017-01-01

    The G-protein beta subunit 3 (GNB3) gene has been implicated in obesity risk; however, the molecular mechanism of GNB3-related disease is unknown. GNB3 duplication is responsible for a syndromic form of childhood obesity, and an activating DNA sequence variant (C825T) in GNB3 is also associated with obesity. To test the hypothesis that GNB3 overexpression causes obesity, we created bacterial artificial chromosome (BAC) transgenic mice that carry an extra copy of the human GNB3 risk allele. Here we show that GNB3-T/+ mice have increased adiposity, but not greater food intake or a defect in satiety. GNB3-T/+ mice have elevated fasting plasma glucose, insulin, and C-peptide, as well as glucose intolerance, indicating type 2 diabetes. Fasting plasma leptin, triglycerides, cholesterol and phospholipids are elevated, suggesting metabolic syndrome. Based on a battery of behavioral tests, GNB3-T/+ mice did not exhibit anxiety- or depressive-like phenotypes. GNB3-T/+ and wild-type animals have similar activity levels and heat production; however, GNB3-T/+ mice exhibit dysregulation of acute thermogenesis. Finally, Ucp1 expression is significantly lower in white adipose tissue (WAT) in GNB3-T/+ mice, suggestive of WAT remodeling that could lead to impaired cellular thermogenesis. Taken together, our study provides the first functional link between GNB3 and obesity, and presents insight into novel pathways that could be applied to combat obesity and type 2 diabetes.

  13. GNB3 overexpression causes obesity and metabolic syndrome.

    Directory of Open Access Journals (Sweden)

    Alev Cagla Ozdemir

    Full Text Available The G-protein beta subunit 3 (GNB3 gene has been implicated in obesity risk; however, the molecular mechanism of GNB3-related disease is unknown. GNB3 duplication is responsible for a syndromic form of childhood obesity, and an activating DNA sequence variant (C825T in GNB3 is also associated with obesity. To test the hypothesis that GNB3 overexpression causes obesity, we created bacterial artificial chromosome (BAC transgenic mice that carry an extra copy of the human GNB3 risk allele. Here we show that GNB3-T/+ mice have increased adiposity, but not greater food intake or a defect in satiety. GNB3-T/+ mice have elevated fasting plasma glucose, insulin, and C-peptide, as well as glucose intolerance, indicating type 2 diabetes. Fasting plasma leptin, triglycerides, cholesterol and phospholipids are elevated, suggesting metabolic syndrome. Based on a battery of behavioral tests, GNB3-T/+ mice did not exhibit anxiety- or depressive-like phenotypes. GNB3-T/+ and wild-type animals have similar activity levels and heat production; however, GNB3-T/+ mice exhibit dysregulation of acute thermogenesis. Finally, Ucp1 expression is significantly lower in white adipose tissue (WAT in GNB3-T/+ mice, suggestive of WAT remodeling that could lead to impaired cellular thermogenesis. Taken together, our study provides the first functional link between GNB3 and obesity, and presents insight into novel pathways that could be applied to combat obesity and type 2 diabetes.

  14. Revolutionizing membrane protein overexpression in bacteria

    NARCIS (Netherlands)

    Schlegel, Susan; Klepsch, Mirjam; Gialama, Dimitra; Wickstrom, David; Slotboom, Dirk Jan; de Gier, Jan-Willem; Wickström, David

    The bacterium Escherichia coli is the most widely used expression host for overexpression trials of membrane proteins. Usually, different strains, culture conditions and expression regimes are screened for to identify the optimal overexpression strategy. However, yields are often not satisfactory,

  15. Twinkle overexpression prevents cardiac rupture after myocardial infarction by alleviating impaired mitochondrial biogenesis.

    Science.gov (United States)

    Inoue, Takahiro; Ikeda, Masataka; Ide, Tomomi; Fujino, Takeo; Matsuo, Yuka; Arai, Shinobu; Saku, Keita; Sunagawa, Kenji

    2016-09-01

    Cardiac rupture is a fatal complication after myocardial infarction (MI). However, the detailed mechanism underlying cardiac rupture after MI remains to be fully elucidated. In this study, we investigated the role of mitochondrial DNA (mtDNA) and mitochondria in the pathophysiology of cardiac rupture by analyzing Twinkle helicase overexpression mice (TW mice). Twinkle overexpression increased mtDNA copy number approximately twofold and ameliorated ischemic cardiomyopathy at day 28 after MI. Notably, Twinkle overexpression markedly prevented cardiac rupture and improved post-MI survival, accompanied by the suppression of MMP-2 and MMP-9 in the MI border area at day 5 after MI when cardiac rupture frequently occurs. Additionally, these cardioprotective effects of Twinkle overexpression were abolished in transgenic mice overexpressing mutant Twinkle with an in-frame duplication of amino acids 353-365, which resulted in no increases in mtDNA copy number. Furthermore, although apoptosis and oxidative stress were induced and mitochondria were damaged in the border area, these injuries were improved in TW mice. Further analysis revealed that mitochondrial biogenesis, including mtDNA copy number, transcription, and translation, was severely impaired in the border area at day 5 In contrast, Twinkle overexpression maintained mtDNA copy number and restored the impaired transcription and translation of mtDNA in the border area. These results demonstrated that Twinkle overexpression alleviated impaired mitochondrial biogenesis in the border area through maintained mtDNA copy number and thereby prevented cardiac rupture accompanied by the reduction of apoptosis and oxidative stress, and suppression of MMP activity. Copyright © 2016 the American Physiological Society.

  16. Human CD36 overexpression in renal tubules accelerates the progression of renal diseases in a mouse model of folic acid-induced acute kidney injury.

    Science.gov (United States)

    Jung, Jong Hwan; Choi, Jee Eun; Song, Ju Hung; Ahn, Seon-Ho

    2018-03-01

    Acute kidney injury (AKI) is a risk factor for progression to chronic kidney disease, with even subclinical AKI episodes progressing to chronic kidney disease. Several risk factors such as preexisting kidney disease, hyperglycemia, and hypertension may aggravate renal disease after AKI. However, mechanisms underlying the progression of AKI are still unclear. This study identified the effect of human cluster of differentiation 36 (CD36) overexpression on the progression of folic acid-induced AKI. Pax8-rtTA/tetracycline response element-human CD36 transgenic mice were used to elucidate the effect of human CD36 overexpression in the proximal tubules on folic acid-induced AKI. Results of histological analysis showed severely dilated tubules with casts and albuminuria in folic acid-treated transgenic mice overexpressing human CD36 compared with folic acid-treated wild-type mice. In addition, analysis of mRNA expression showed a significant increase in the collagen 3a1 gene in folic acid-treated transgenic mice overexpressing human CD 36 compared with folic acid-treated wild type mice. Human CD36-overexpressing transgenic mice showed severe pathological changes and albuminuria compared with wild-type mice. Moreover, mRNA expression of the collagen 3a1 gene increased in folic acid-treated transgenic mice. These results suggest that human CD36 overexpression is a risk factor of AKI and its progression to chronic kidney disease.

  17. Human CD36 overexpression in renal tubules accelerates the progression of renal diseases in a mouse model of folic acid-induced acute kidney injury

    Directory of Open Access Journals (Sweden)

    Jong Hwan Jung

    2018-03-01

    Full Text Available Background : Acute kidney injury (AKI is a risk factor for progression to chronic kidney disease, with even subclinical AKI episodes progressing to chronic kidney disease. Several risk factors such as preexisting kidney disease, hyperglycemia, and hypertension may aggravate renal disease after AKI. However, mechanisms underlying the progression of AKI are still unclear. This study identified the effect of human cluster of differentiation 36 (CD36 overexpression on the progression of folic acid-induced AKI. Methods : Pax8-rtTA/tetracycline response element-human CD36 transgenic mice were used to elucidate the effect of human CD36 overexpression in the proximal tubules on folic acid-induced AKI. Results : Results of histological analysis showed severely dilated tubules with casts and albuminuria in folic acid-treated transgenic mice overexpressing human CD36 compared with folic acid-treated wild-type mice. In addition, analysis of mRNA expression showed a significant increase in the collagen 3a1 gene in folic acid-treated transgenic mice overexpressing human CD 36 compared with folic acid-treated wild type mice. Conclusion : Human CD36-overexpressing transgenic mice showed severe pathological changes and albuminuria compared with wild-type mice. Moreover, mRNA expression of the collagen 3a1 gene increased in folic acid-treated transgenic mice. These results suggest that human CD36 overexpression is a risk factor of AKI and its progression to chronic kidney disease.

  18. Pancreatic beta-cell overexpression of the glucagon receptor gene results in enhanced beta-cell function and mass

    DEFF Research Database (Denmark)

    Gelling, Richard W; Vuguin, Patricia M; Du, Xiu Quan

    2009-01-01

    in vivo, we generated mice overexpressing the Gcgr specifically on pancreatic beta-cells (RIP-Gcgr). In vivo and in vitro insulin secretion in response to glucagon and glucose was increased 1.7- to 3.9-fold in RIP-Gcgr mice compared with controls. Consistent with the observed increase in insulin release...

  19. Gene Overexpression: Uses, Mechanisms, and Interpretation

    Science.gov (United States)

    2012-01-01

    The classical genetic approach for exploring biological pathways typically begins by identifying mutations that cause a phenotype of interest. Overexpression or misexpression of a wild-type gene product, however, can also cause mutant phenotypes, providing geneticists with an alternative yet powerful tool to identify pathway components that might remain undetected using traditional loss-of-function analysis. This review describes the history of overexpression, the mechanisms that are responsible for overexpression phenotypes, tests that begin to distinguish between those mechanisms, the varied ways in which overexpression is used, the methods and reagents available in several organisms, and the relevance of overexpression to human disease. PMID:22419077

  20. Overexpression of catalase in myeloid cells causes impaired postischemic neovascularization.

    Science.gov (United States)

    Hodara, Roberto; Weiss, Daiana; Joseph, Giji; Velasquez-Castano, Juan C; Landázuri, Natalia; Han, Ji Woong; Yoon, Young-sup; Taylor, W Robert

    2011-10-01

    Myeloid lineage cells (MLCs) such as macrophages are known to play a key role in postischemic neovascularization. However, the role of MLC-derived reactive oxygen species in this process and their specific chemical identity remain unknown. Transgenic mice with MLC-specific overexpression of catalase (Tg(Cat-MLC) mice) were created on a C57BL/6 background. Macrophage catalase activity was increased 3.4-fold compared with wild-type mice. After femoral artery ligation, laser Doppler perfusion imaging revealed impaired perfusion recovery in Tg(Cat-MLC) mice. This was associated with fewer collateral vessels, as assessed by microcomputed tomography angiography, and decreased capillary density. Impaired functional recovery of the ischemic limb was also evidenced by a 50% reduction in spontaneous running activity. The deficient neovascularization was associated with a blunted inflammatory response, characterized by decreased macrophage infiltration of ischemic tissues, and lower mRNA levels of inflammatory markers, such as tumor necrosis factor-α, osteopontin, and matrix mettaloproteinase-9. In vitro macrophage migration was impaired in Tg(Cat-MLC) mice, suggesting a role for H(2)O(2) in regulating the ability of macrophages to infiltrate ischemic tissues. MLC-derived H(2)O(2) plays a key role in promoting neovascularization in response to ischemia and is a necessary factor for the development of ischemia-induced inflammation.

  1. E2F-1-Induced p53-independent apoptosis in transgenic mice

    DEFF Research Database (Denmark)

    Holmberg, Christian Henrik; Helin, K.; Sehested, M.

    1998-01-01

    involving increased apoptosis in the germinal epithelium. This effect was potentiated by simultaneous overexpression of DP-1. Testicular atrophy as a result of overexpression of E2F-1 and DP-1 is independent of functional p53, since p53-nullizygous transgenic mice overexpressing E2F-1 and DP-1 also suffered...

  2. Immunological and Clinical Effects of Vaccines Targeting p53-Overexpressing Malignancies

    NARCIS (Netherlands)

    Vermeij, R.; Leffers, N.; van der Burg, S. H.; Melief, C. J.; Daemen, T.; Nijman, H. W.

    2011-01-01

    Approximately 50% of human malignancies carry p53 mutations, which makes it a potential antigenic target for cancer immunotherapy. Adoptive transfer with p53-specific cytotoxic T-lymphocytes (CTL) and CD4(+) T-helper cells eradicates p53-overexpressing tumors in mice. Furthermore, p53 antibodies and

  3. Sarcolipin overexpression improves muscle energetics and reduces fatigue

    Science.gov (United States)

    Sopariwala, Danesh H.; Pant, Meghna; Shaikh, Sana A.; Goonasekera, Sanjeewa A.; Molkentin, Jeffery D.; Weisleder, Noah; Ma, Jianjie; Pan, Zui

    2015-01-01

    Sarcolipin (SLN) is a regulator of sarcoendoplasmic reticulum calcium ATPase in skeletal muscle. Recent studies using SLN-null mice have identified SLN as a key player in muscle thermogenesis and metabolism. In this study, we exploited a SLN overexpression (SlnOE) mouse model to determine whether increased SLN level affected muscle contractile properties, exercise capacity/fatigue, and metabolic rate in whole animals and isolated muscle. We found that SlnOE mice are more resistant to fatigue and can run significantly longer distances than wild-type (WT). Studies with isolated extensor digitorum longus (EDL) muscles showed that SlnOE EDL produced higher twitch force than WT. The force-frequency curves were not different between WT and SlnOE EDLs, but at lower frequencies the pyruvate-induced potentiation of force was significantly higher in SlnOE EDL. SLN overexpression did not alter the twitch and force-frequency curve in isolated soleus muscle. However, during a 10-min fatigue protocol, both EDL and soleus from SlnOE mice fatigued significantly less than WT muscles. Interestingly, SlnOE muscles showed higher carnitine palmitoyl transferase-1 protein expression, which could enhance fatty acid metabolism. In addition, lactate dehydrogenase expression was higher in SlnOE EDL, suggesting increased glycolytic capacity. We also found an increase in store-operated calcium entry (SOCE) in isolated flexor digitorum brevis fibers of SlnOE compared with WT mice. These data allow us to conclude that increased SLN expression improves skeletal muscle performance during prolonged muscle activity by increasing SOCE and muscle energetics. PMID:25701006

  4. MMP20 Overexpression Disrupts Molar Ameloblast Polarity and Migration.

    Science.gov (United States)

    Shin, M; Chavez, M B; Ikeda, A; Foster, B L; Bartlett, J D

    2018-02-01

    Ameloblasts responsible for enamel formation express matrix metalloproteinase 20 (MMP20), an enzyme that cleaves enamel matrix proteins, including amelogenin (AMELX) and ameloblastin (AMBN). Previously, we showed that continuously erupting incisors from transgenic mice overexpressing active MMP20 had a massive cell infiltrate present within their enamel space, leading to enamel mineralization defects. However, effects of MMP20 overexpression on mouse molars were not analyzed, although these teeth more accurately represent human odontogenesis. Therefore, MMP20-overexpressing mice ( Mmp20 +/+ Tg + ) were assessed by multiscale analyses, combining several approaches from high-resolution micro-computed tomography to enamel organ immunoblots. During the secretory stage at postnatal day 6 (P6), Mmp20 +/+ Tg + mice had a discontinuous ameloblast layer and, unlike incisors, molar P12 maturation stage ameloblasts abnormally migrated away from the enamel layer into the stratum intermedium/stellate reticulum. TOPflash assays performed in vitro demonstrated that MMP20 expression promoted β-catenin nuclear localization and that MMP20 expression promoted invasion through Matrigel-coated filters. However, for both assays, significant differences were eliminated in the presence of the β-catenin inhibitor ICG-001. This suggests that MMP20 activity promotes cell migration via the Wnt pathway. In vivo, the unique molar migration of amelogenin-expressing ameloblasts was associated with abnormal deposition of ectopic calcified nodules surrounding the adherent enamel layer. Enamel content was assessed just prior to eruption at P15. Compared to wild-type, Mmp20 +/+ Tg + molars exhibited significant reductions in enamel thickness (70%), volume (60%), and mineral density (40%), and MMP20 overexpression resulted in premature cleavage of AMBN, which likely contributed to the severe defects in enamel mineralization. In addition, Mmp20 +/+ Tg + mouse molar enamel organs had increased levels

  5. Over-expression of thymosin beta 4 promotes abnormal tooth development and stimulation of hair growth.

    Science.gov (United States)

    Cha, Hee-Jae; Philp, Deborah; Lee, Soo-Hyun; Moon, Hye-Sung; Kleinman, Hynda K; Nakamura, Takashi

    2010-01-01

    Thymosin beta 4 has multi-functional roles in cell physiology. It accelerates wound healing, hair growth and angiogenesis, and increases laminin-5 expression in corneal epithelium. Furthermore, thymosin beta 4 stimulates tumor growth and metastasis by induction of cell migration and vascular endothelial growth factor-mediated angiogenesis. Using a construct on the skin-specific keratin-5 promoter, we have developed thymosin beta 4 over-expressing transgenic mice to further study its functional roles. Thymosin beta 4 in adult skin and in embryonic stages of the transgenic mouse was analyzed by both Western blot and immunohistochemistry. The over-expression of thymosin beta 4 was observed especially around hair follicles and in the teeth in the transgenic mice. We examined the phenotype of the thymosin beta 4 over-expressing mice. Hair growth was accelerated. In addition, the transgenic mice had abnormally-shaped white teeth and dull incisors. We found that the expression of laminin-5 was up-regulated in the skin of the transgenic mice. We conclude that thymosin beta 4 has an important physiological role in hair growth and in tooth development.

  6. Overexpression of hepatoma-derived growth factor in melanocytes does not lead to oncogenic transformation

    International Nuclear Information System (INIS)

    Sedlmaier, Angela; Wernert, Nicolas; Gallitzendörfer, Rainer; Abouzied, Mekky M; Gieselmann, Volkmar; Franken, Sebastian

    2011-01-01

    HDGF is a growth factor which is overexpressed in a wide range of tumors. Importantly, expression levels were identified as a prognostic marker in some types of cancer such as melanoma. To investigate the presumed oncogenic/transforming capacity of HDGF, we generated transgenic mice overexpressing HDGF in melanocytes. These mice were bred with mice heterozygous for a defective copy of the Ink4a tumor suppressor gene and were exposed to UV light to increase the risk for tumor development both genetically and physiochemically. Mice were analyzed by immunohistochemistry and Western blotting. Furthermore, primary melanocytes were isolated from different strains created. Transgenic animals overexpressed HDGF in hair follicle melanocytes. Interestingly, primary melanocytes isolated from transgenic animals were not able to differentiate in vitro whereas cells isolated from wild type and HDGF-deficient animals were. Although, HDGF -/- /Ink4a +/- mice displayed an increased number of epidermoid cysts after exposure to UV light, no melanomas or premelanocytic alterations could be detected in this mouse model. The results therefore provide no evidence that HDGF has a transforming capacity in tumor development. Our results in combination with previous findings point to a possible role in cell differentiation and suggest that HDGF promotes tumor progression after secondary upregulation and may represent another protein fitting into the concept of non-oncogene addiction of tumor tissue

  7. NUCKS overexpression in breast cancer

    Directory of Open Access Journals (Sweden)

    Kittas Christos

    2009-08-01

    Full Text Available Abstract Background NUCKS (Nuclear, Casein Kinase and Cyclin-dependent Kinase Substrate is a nuclear, DNA-binding and highly phosphorylated protein. A number of reports show that NUCKS is highly expressed on the level of mRNA in several human cancers, including breast cancer. In this work, NUCKS expression on both RNA and protein levels was studied in breast tissue biopsies consisted of invasive carcinomas, intraductal proliferative lesions, benign epithelial proliferations and fibroadenomas, as well as in primary cultures derived from the above biopsies. Specifically, in order to evaluate the level of NUCKS protein in correlation with the histopathological features of breast disease, immunohistochemistry was employed on paraffin sections of breast biopsies of the above types. In addition, NUCKS expression was studied by means of Reverse Transcription PCR (RT-PCR, real-time PCR (qRT-PCR and Western immunoblot analyses in the primary cell cultures developed from the same biopsies. Results The immunohistochemical Results showed intense NUCKS staining mostly in grade I and II breast carcinomas compared to normal tissues. Furthermore, NUCKS was moderate expressed in benign epithelial proliferations, such as adenosis and sclerosing adenosis, and highly expressed in intraductal lesions, specifically in ductal carcinomas in situ (DCIS. It is worth noting that all the fibroadenoma tissues examined were negative for NUCKS staining. RT-PCR and qRT-PCR showed an increase of NUCKS expression in cells derived from primary cultures of proliferative lesions and cancerous tissues compared to the ones derived from normal breast tissues and fibroadenomas. This increase was also confirmed by Western immunoblot analysis. Although NUCKS is a cell cycle related protein, its expression does not correlate with Ki67 expression, neither in tissue sections nor in primary cell cultures. Conclusion The results show overexpression of the NUCKS protein in a number of non

  8. Overexpression of Myo1e in mouse podocytes enhances cellular endocytosis, migration, and adhesion.

    Science.gov (United States)

    Jin, Xia; Wang, Wenjing; Mao, Jianhua; Shen, Huijun; Fu, Haidong; Wang, Xia; Gu, Weizhong; Liu, Aimin; Yu, Huimin; Shu, Qiang; Du, Lizhong

    2014-02-01

    Podocytes are a terminally differentiated and highly specialized cell type in the glomerulus that forms a crucial component of the glomerular filtration barrier. Recently, Myo1e was identified in the podocytes of glomeruli. Myo1e podocyte-specific knockout mice exhibit proteinuria, podocyte foot process effacement, glomerular basement membrane disorganization, signs of chronic renal injury, and kidney inflammation. After overexpression of Myo1e in a conditionally immortalized mouse podocyte cell line (MPC5), podocyte migration was evaluated via transwell assay, endocytosis was evaluated using FITC-transferrin, and adhesion was evaluated using a detachment assay after puromycin aminonucleoside treatment. Myo1e overexpression significantly increased the adherence of podocytes. ANOVA analysis indicated significant differences for cell adhesion between the overexpression and control groups (overexpression vs. control, t = 11.3199, P = 0.005; overexpression vs. negative control, t = 12.0570, P = 0.0006). Overexpression of Myo1e inhibited puromycin aminonucleoside-induced podocyte detachment, and the number of cells remaining on the bottom of the culture plate increased. Cell migration was enhanced in Myo1e-overexpressing podocytes in the transwell migration assay. Internalization of FITC-transferrin also increased in Myo1e-overexpressing podocytes relative to control cells. Overexpression of Myo1e can enhance podocyte migration ability, endocytosis, and attachment to the glomerular basement membrane. Restoration of Myo1e expression in podocytes may therefore strengthen their functional integrity against environmental and mechanical injury. © 2013 Wiley Periodicals, Inc.

  9. Dek overexpression in murine epithelia increases overt esophageal squamous cell carcinoma incidence

    Science.gov (United States)

    Cimperman, Katherine A.; Haas, Sarah R.; Guasch, Geraldine; Waclaw, Ronald R.; Komurov, Kakajan; Lane, Adam; Wikenheiser-Brokamp, Kathryn A.

    2018-01-01

    Esophageal cancer occurs as either squamous cell carcinoma (ESCC) or adenocarcinoma. ESCCs comprise almost 90% of cases worldwide, and recur with a less than 15% five-year survival rate despite available treatments. The identification of new ESCC drivers and therapeutic targets is critical for improving outcomes. Here we report that expression of the human DEK oncogene is strongly upregulated in esophageal SCC based on data in the cancer genome atlas (TCGA). DEK is a chromatin-associated protein with important roles in several nuclear processes including gene transcription, epigenetics, and DNA repair. Our previous data have utilized a murine knockout model to demonstrate that Dek expression is required for oral and esophageal SCC growth. Also, DEK overexpression in human keratinocytes, the cell of origin for SCC, was sufficient to cause hyperplasia in 3D organotypic raft cultures that mimic human skin, thus linking high DEK expression in keratinocytes to oncogenic phenotypes. However, the role of DEK over-expression in ESCC development remains unknown in human cells or genetic mouse models. To define the consequences of Dek overexpression in vivo, we generated and validated a tetracycline responsive Dek transgenic mouse model referred to as Bi-L-Dek. Dek overexpression was induced in the basal keratinocytes of stratified squamous epithelium by crossing Bi-L-Dek mice to keratin 5 tetracycline transactivator (K5-tTA) mice. Conditional transgene expression was validated in the resulting Bi-L-Dek_K5-tTA mice and was suppressed with doxycycline treatment in the tetracycline-off system. The mice were subjected to an established HNSCC and esophageal carcinogenesis protocol using the chemical carcinogen 4-nitroquinoline 1-oxide (4NQO). Dek overexpression stimulated gross esophageal tumor development, when compared to doxycycline treated control mice. Furthermore, high Dek expression caused a trend toward esophageal hyperplasia in 4NQO treated mice. Taken together, these

  10. Astrocyte-Dependent Vulnerability to Excitotoxicity in Spermine Oxidase-Overexpressing Mouse.

    Science.gov (United States)

    Cervetto, Chiara; Vergani, Laura; Passalacqua, Mario; Ragazzoni, Milena; Venturini, Arianna; Cecconi, Francesco; Berretta, Nicola; Mercuri, Nicola; D'Amelio, Marcello; Maura, Guido; Mariottini, Paolo; Voci, Adriana; Marcoli, Manuela; Cervelli, Manuela

    2016-03-01

    Transgenic mice overexpressing spermine oxidase (SMO) in the cerebral cortex (Dach-SMO mice) showed increased vulnerability to excitotoxic brain injury and kainate-induced epileptic seizures. To investigate the mechanisms by which SMO overexpression leads to increased susceptibility to kainate excitotoxicity and seizure, in the cerebral cortex of Dach-SMO and control mice we assessed markers for astrocyte proliferation and neuron loss, and the ability of kainate to evoke glutamate release from nerve terminals and astrocyte processes. Moreover, we assessed a possible role of astrocytes in an in vitro model of epileptic-like activity in combined cortico-hippocampal slices recorded with a multi-electrode array device. In parallel, as the brain is a major metabolizer of oxygen and yet has relatively feeble protective antioxidant mechanisms, we analyzed the oxidative status of the cerebral cortex of both SMO-overexpressing and control mice by evaluating enzymatic and non-enzymatic scavengers such as metallothioneins. The main findings in the cerebral cortex of Dach-SMO mice as compared to controls are the following: astrocyte activation and neuron loss; increased oxidative stress and activation of defense mechanisms involving both neurons and astrocytes; increased susceptibility to kainate-evoked cortical epileptogenic activity, dependent on astrocyte function; appearance of a glutamate-releasing response to kainate from astrocyte processes due to activation of Ca(2+)-permeable AMPA receptors in Dach-SMO mice. We conclude that reactive astrocytosis and activation of glutamate release from astrocyte processes might contribute, together with increased reactive oxygen species production, to the vulnerability to kainate excitotoxicity in Dach-SMO mice. This mouse model with a deregulated polyamine metabolism would shed light on roles for astrocytes in increasing vulnerability to excitotoxic neuron injury.

  11. Lung disease phenotypes caused by overexpression of combinations of α-, β-, and γ-subunits of the epithelial sodium channel in mouse airways.

    Science.gov (United States)

    Livraghi-Butrico, Alessandra; Wilkinson, Kristen J; Volmer, Allison S; Gilmore, Rodney C; Rogers, Troy D; Caldwell, Ray A; Burns, Kimberlie A; Esther, Charles R; Mall, Marcus A; Boucher, Richard C; O'Neal, Wanda K; Grubb, Barbara R

    2018-02-01

    The epithelial Na + channel (ENaC) regulates airway surface hydration. In mouse airways, ENaC is composed of three subunits, α, β, and γ, which are differentially expressed (α > β > γ). Airway-targeted overexpression of the β subunit results in Na + hyperabsorption, causing airway surface dehydration, hyperconcentrated mucus with delayed clearance, lung inflammation, and perinatal mortality. Notably, mice overexpressing the α- or γ-subunit do not exhibit airway Na + hyperabsorption or lung pathology. To test whether overexpression of multiple ENaC subunits produced Na + transport and disease severity exceeding that of βENaC-Tg mice, we generated double (αβ, αγ, βγ) and triple (αβγ) transgenic mice and characterized their lung phenotypes. Double αγENaC-Tg mice were indistinguishable from WT littermates. In contrast, double βγENaC-Tg mice exhibited airway Na + absorption greater than that of βENaC-Tg mice, which was paralleled by worse survival, decreased mucociliary clearance, and more severe lung pathology. Double αβENaC-Tg mice exhibited Na + transport rates comparable to those of βENaC-Tg littermates. However, αβENaC-Tg mice had poorer survival and developed severe parenchymal consolidation. In situ hybridization (RNAscope) analysis revealed both alveolar and airway αENaC-Tg overexpression. Triple αβγENaC-Tg mice were born in Mendelian proportions but died within the first day of life, and the small sample size prevented analyses of cause(s) of death. Cumulatively, these results indicate that overexpression of βENaC is rate limiting for generation of pathological airway surface dehydration. Notably, airway co-overexpression of β- and γENaC had additive effects on Na + transport and disease severity, suggesting dose dependency of these two variables.

  12. Overexpression of mouse TTF-2 gene causes cleft palate

    Science.gov (United States)

    Meng, Tian; Shi, Jia-Yu; Wu, Min; Wang, Yan; Li, Ling; Liu, Yan; Zheng, Qian; Huang, Lei; Shi, Bing

    2012-01-01

    In humans, mutations of the gene encoding for thyroid transcription factor-2 (TTF-2 or FOXE1) result in Bamforth syndrome. Bamforth syndrome is characterized by agenesis, cleft palate, spiky hair and choanal atresia. TTF-2 null mice (TTF-2−/−) also exhibit cleft palate, suggesting its involvement in the palatogenesis. However, the molecular pathology and genetic regulation by TTF2 remain largely unknown. In the present study, the recombinant expression vector pBROAD3-TTF-2 containing the promoter of the mouse ROSA26 gene was created to form the structural gene of mouse TTF-2 and was microinjected into the male pronuclei of fertilized ova. Sequence analysis confirmed that the TTF-2 transgenic mouse model was established successfully. The transgenic mice displayed a phenotype of cleft palate. In addition, we found that TTF-2 was highly expressed in the medial edge epithelium (MEE) from the embryonic day 12.5 (E12.5) to E14.5 in TTF-2 transgenic mice. These observations suggest that overexpression of TTF-2 during palatogenesis may contribute to formation of cleft palate. PMID:22304410

  13. Overexpression of thrombospondin-1 reduces growth and vascular index but not perfusion in glioblastoma

    DEFF Research Database (Denmark)

    Kragh, Michael; Quistorff, Bjørn; Tenan, Mirna

    2002-01-01

    Little is known about the effects of antiangiogenic therapy on perfusion of human tumors and the mechanisms by which tumors can adapt to these treatments and recur. Here, we examined the effects of serial passaging of LN-229 human glioma xenografts overexpressing thrombospondin (TSP)-1 on tumor...... growth, vascularity, and perfusion. Persistence of TSP-1 overexpression was confirmed after three serial s.c. passages of small xenografted tumor blocks of cells stably transfected with TSP-1 cDNA (clones C9 and E7) or vector controls (pooled clones A7-A9) in immunodeficient nu/nu mice. The tumor...... vascularity was estimated by noninvasive near infrared spectroscopy measuring blood volume at 800 +/- 10 nm and by histological vessel scores in CD31-immunostained cryosections. The tumor perfusion was assessed by noninvasive laser Doppler flowmetry. Overexpression of TSP-1 significantly inhibited tumor...

  14. Smad2 overexpression enhances adhesion of gingival epithelial cells.

    Science.gov (United States)

    Hongo, Shoichi; Yamamoto, Tadashi; Yamashiro, Keisuke; Shimoe, Masayuki; Tomikawa, Kazuya; Ugawa, Yuki; Kochi, Shinsuke; Ideguchi, Hidetaka; Maeda, Hiroshi; Takashiba, Shogo

    2016-11-01

    Gingival epithelial cells play an important role in preventing the initiation of periodontitis, by their hemidesmosomal adhesion to the tooth root surface. Adhesion requires integrin-extracellular matrix (ECM) interactions that are intricately regulated by transforming growth factor-β (TGF-β) signaling. However, the mechanisms underlying the interplay between adhesion molecules and TGF-β, especially the respective roles of Smad2 and Smad3, remain elusive. In this study, we examined the effects of Smad overexpression on gingival epithelial cell adhesion and expression profiles of integrin and ECM-related genes. Human gingival epithelial cells immortalized by the SV40 T-antigen were transfected with Smad2- and Smad3-overexpression vectors. A cell adhesion assay involving fluorescence detection of attached cells was performed using the ArrayScan imaging system. Real-time PCR was performed to examine the kinetics of integrin and ECM gene expression. In vitro and in vivo localization of adhesion molecules was examined by immunofluorescence analysis. By using SB431542, a specific inhibitor of the TGF-β type I receptor, Smad2/3 signaling was confirmed to be dominant in TGF-β1-induced cell adhesion. The Smad2-transfectant demonstrated higher potency for cell adhesion and integrin expression (α2, α5, β4, and β6) than the Smad3-transfectant, whereas little or no change in ECM expression was observed in either transfectant. Moreover, the gingival epithelium of transgenic mice that overexpressed Smad2 driven by the keratin 14 promoter showed increased integrin α2 expression. These findings indicate the crucial role of Smad2 in increased adhesion of gingival epithelial cells via upregulation of integrin α2. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Expression Analysis of cPLA2 Alpha Interacting TIP60 in Diabetic KKAy and Non-Diabetic C57BL Wild-Type Mice: No Impact of Transient and Stable TIP60 Overexpression on Glucose-Stimulated Insulin Secretion in Pancreatic Beta-Cells

    DEFF Research Database (Denmark)

    Nordentoft, Iver; Jeppesen, Per B; Nielsen, Anders L

    2007-01-01

    In the present study we investigate the expression levels of cytosolic phospholipase A2 alpha (cPLA2alpha) interacting histone acetyl transferase proteins TIP60alpha and TIP60beta in non-diabetic C57BL wild-type mice and obese type 2 diabetic KKAy model mice. The aim was to test our hypothesis...

  16. Bmi1 is essential for cerebellar development and is overexpressed in human medulloblastomas.

    Science.gov (United States)

    Leung, Carly; Lingbeek, Merel; Shakhova, Olga; Liu, James; Tanger, Ellen; Saremaslani, Parvin; Van Lohuizen, Maarten; Marino, Silvia

    2004-03-18

    Overexpression of the polycomb group gene Bmi1 promotes cell proliferation and induces leukaemia through repression of Cdkn2a (also known as ink4a/Arf) tumour suppressors. Conversely, loss of Bmi1 leads to haematological defects and severe progressive neurological abnormalities in which de-repression of the ink4a/Arf locus is critically implicated. Here, we show that Bmi1 is strongly expressed in proliferating cerebellar precursor cells in mice and humans. Using Bmi1-null mice we demonstrate a crucial role for Bmi1 in clonal expansion of granule cell precursors both in vivo and in vitro. Deregulated proliferation of these progenitor cells, by activation of the sonic hedgehog (Shh) pathway, leads to medulloblastoma development. We also demonstrate linked overexpression of BMI1 and patched (PTCH), suggestive of SHH pathway activation, in a substantial fraction of primary human medulloblastomas. Together with the rapid induction of Bmi1 expression on addition of Shh or on overexpression of the Shh target Gli1 in cerebellar granule cell cultures, these findings implicate BMI1 overexpression as an alternative or additive mechanism in the pathogenesis of medulloblastomas, and highlight a role for Bmi1-containing polycomb complexes in proliferation of cerebellar precursor cells.

  17. Cardiac remodeling is not modulated by overexpression of muscle LIM protein (MLP).

    Science.gov (United States)

    Kuhn, Christian; Frank, Derk; Dierck, Franziska; Oehl, Ulrike; Krebs, Jutta; Will, Rainer; Lehmann, Lorenz H; Backs, Johannes; Katus, Hugo A; Frey, Norbert

    2012-05-01

    Muscle LIM protein (MLP) has been proposed to be a central player in the pathogenesis of heart muscle disease. In line with this notion, the homozygous loss of MLP results in cardiac hypertrophy and dilated cardiomyopathy. Moreover, MLP is induced in several models of cardiac hypertrophy such as aortic banding and myocardial infarction. We thus hypothesized that overexpression of MLP might change the hypertrophic response to cardiac stress. In order to answer the question whether MLP modulates cardiac hypertrophy in vivo, we generated a novel transgenic mouse model with cardiac-specific overexpression of MLP. Three independent transgenic lines did not show a pathological phenotype under baseline conditions. Specifically, contractile function and heart weight to body weight ratios at different ages were normal. Next, the transgenic animals were challenged with pressure overload due to aortic constriction. Surprisingly, transgenic mice developed cardiac hypertrophy to the same extent as their wild-type littermates. Moreover, neither contractile dysfunction nor pathological gene expression in response to pressure overload were differentially affected by MLP overexpression. Finally, in a milder in vivo model of hypertrophy induced by chronic infusion of angiotensin-II, cardiac mass and hypertrophic gene expression were again identical in MLP transgenic mice and controls. Taken together, we provide evidence that cardiac overexpression of MLP does not modulate the heart's response to various forms of pathological stress.

  18. Critical role of c-Jun overexpression in liver metastasis of human breast cancer xenograft model

    International Nuclear Information System (INIS)

    Zhang, Yan; Hu, Meiru; Shen, Beifen; Guo, Ning; Pu, Xiaoyun; Shi, Ming; Chen, Liyong; Song, Yuhua; Qian, Lu; Yuan, Guogang; Zhang, Hao; Yu, Ming

    2007-01-01

    c-Jun/AP-1 has been linked to invasive properties of aggressive breast cancer. Recently, it has been reported that overexpression of c-Jun in breast cancer cell line MCF-7 resulted in increased AP-1 activity, motility and invasiveness of the cells in vitro and tumor formation in nude mice. However, the role of c-Jun in metastasis of human breast cancer in vivo is currently unknown. To further investigate the direct involvement of c-Jun in tumorigenesis and metastasis, in the present study, the effects of c-Jun overexpression were studied in both in vitro and in nude mice. Ectopic overexpression of c-Jun promoted the growth of MCF-7 cells and resulted in a significant increase in the percentage of cells in S phase and increased motility and invasiveness. Introduction of c-Jun gene alone into weakly invasive MCF-7 cells resulted in the transfected cells capable of metastasizing to the nude mouse liver following tail vein injection. The present study confirms that overexpression of c-Jun contributes to a more invasive phenotype in MCF-7 cells. It indicates an interesting relationship between c-Jun expression and increased property of adhesion, migration and in vivo liver metastasis of MCF-7/c-Jun cells. The results provide further evidence that c-Jun is involved in the metastasis of breast cancer. The finding also opens an opportunity for development of anti-c-Jun strategies in breast cancer therapy

  19. Overexpression of Rad in muscle worsens diet-induced insulin resistance and glucose intolerance and lowers plasma triglyceride level

    Science.gov (United States)

    Ilany, Jacob; Bilan, Philip J.; Kapur, Sonia; Caldwell, James S.; Patti, Mary-Elizabeth; Marette, Andre; Kahn, C. Ronald

    2006-03-01

    Rad is a low molecular weight GTPase that is overexpressed in skeletal muscle of some patients with type 2 diabetes mellitus and/or obesity. Overexpression of Rad in adipocytes and muscle cells in culture results in diminished insulin-stimulated glucose uptake. To further elucidate the potential role of Rad in vivo, we have generated transgenic (tg) mice that overexpress Rad in muscle using the muscle creatine kinase (MCK) promoter-enhancer. Rad tg mice have a 6- to 12-fold increase in Rad expression in muscle as compared to wild-type littermates. Rad tg mice grow normally and have normal glucose tolerance and insulin sensitivity, but have reduced plasma triglyceride levels. On a high-fat diet, Rad tg mice develop more severe glucose intolerance than the wild-type mice; this is due to increased insulin resistance in muscle, as exemplified by a rightward shift in the dose-response curve for insulin stimulated 2-deoxyglucose uptake. There is also a unexpected further reduction of the plasma triglyceride levels that is associated with increased levels of lipoprotein lipase in the Rad tg mice. These results demonstrate a potential synergistic interaction between increased expression of Rad and high-fat diet in creation of insulin resistance and altered lipid metabolism present in type 2 diabetes. diabetes mellitus | glucose transport | RGK GTPase | transgenic mouse

  20. Cardiac-Specific Overexpression of Catalase Attenuates Lipopolysaccharide-Induced Myocardial Contractile Dysfunction: Role of Autophagy

    OpenAIRE

    Turdi, Subat; Han, Xuefeng; Huff, Anna F.; Roe, Nathan D.; Hu, Nan; Gao, Feng; Ren, Jun

    2012-01-01

    Lipopolysaccharide (LPS) from Gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complication in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged ...

  1. Pancreatic beta-cell lipotoxicity induced by overexpression of hormone-sensitive lipase

    DEFF Research Database (Denmark)

    Winzell, Maria Sörhede; Svensson, Håkan; Enerbäck, Sven

    2003-01-01

    Lipid perturbations associated with triglyceride overstorage in beta-cells impair insulin secretion, a process termed lipotoxicity. To assess the role of hormone-sensitive lipase, which is expressed and enzymatically active in beta-cells, in the development of lipotoxicity, we generated transgenic...... mice overexpressing hormone-sensitive lipase specifically in beta-cells. Transgenic mice developed glucose intolerance and severely blunted glucose-stimulated insulin secretion when challenged with a high-fat diet. As expected, both lipase activity and forskolin-stimulated lipolysis was increased...

  2. A new transgenic mouse model for conditional overexpression of the Polycomb Group protein EZH2.

    Science.gov (United States)

    Koppens, Martijn A J; Tanger, Ellen; Nacerddine, Karim; Westerman, Bart; Song, Ji-Ying; van Lohuizen, Maarten

    2017-04-01

    The Polycomb Group protein EZH2 is upregulated in most prostate cancers, and its overexpression is associated with poor prognosis. Most insights into the functional role of EZH2 in prostate cancer have been gained using cell lines and EZH2 inactivation studies. However, the question remains whether overexpression of EZH2 can initiate prostate tumourigenesis or drive tumour progression. Appropriate transgenic mouse models that are required to answer such questions are lacking. We developed one such transgenic mouse model for conditional overexpression of Ezh2. In this transgene, Ezh2 and Luciferase are transcribed from a single open reading frame. The latter gene enables intravital bioluminescent imaging of tissues expressing this transgene, allowing the detection of tumour outgrowth and potential metastatic progression over time. Prostate-specific Ezh2 overexpression by crossbreeding with Probasin-Cre mice led to neoplastic prostate lesions at low incidence and with a long latency. Compounding a previously described Bmi1-transgene and Pten-deficiency prostate cancer mouse model with the Ezh2 transgene did not enhance tumour progression or drive metastasis formation. In conclusion, we here report the generation of a wildtype Ezh2 overexpression mouse model that allows for intravital surveillance of tissues with activated transgene. This model will be an invaluable tool for further unravelling the role of EZH2 in cancer.

  3. Cardiomyocyte Overexpression of FABP4 Aggravates Pressure Overload-Induced Heart Hypertrophy.

    Directory of Open Access Journals (Sweden)

    Ji Zhang

    Full Text Available Fatty acid binding protein 4 (FABP4 is a member of the intracellular lipid-binding protein family, responsible for the transportation of fatty acids. It is considered to express mainly in adipose tissues, and be strongly associated with inflammation, obesity, diabetes and cardiovasculardiseases. Here we report that FABP4 is also expressed in cardiomyocytes and plays an important role in regulating heart function under pressure overload. We generated heart-specific transgenic FABP4 (FABP4-TG mice using α myosin-heavy chain (α-MHC promoter and human FABP4 sequence, resulting in over-expression of FABP4 in cardiomyocytes. The FABP4-TG mice displayed normal cardiac morphology and contractile function. When they were subjected to the transverse aorta constriction (TAC procedure, the FABP4-TG mice developed more cardiac hypertrophy correlated with significantly increased ERK phosphorylation, compared with wild type controls. FABP4 over-expression in cardiomyocytes activated phosphor-ERK signal and up-regulate the expression of cardiac hypertrophic marker genes. Conversely, FABP4 induced phosphor-ERK signal and hypertrophic gene expressions can be markedly inhibited by an ERK inhibitor PD098059 as well as the FABP4 inhibitor BMS309403. These results suggest that FABP4 over-expression in cardiomyocytes can aggravate the development of cardiac hypertrophy through the activation of ERK signal pathway.

  4. Transgenic overexpression of mitofilin attenuates diabetes mellitus-associated cardiac and mitochondria dysfunction.

    Science.gov (United States)

    Thapa, Dharendra; Nichols, Cody E; Lewis, Sara E; Shepherd, Danielle L; Jagannathan, Rajaganapathi; Croston, Tara L; Tveter, Kevin J; Holden, Anthony A; Baseler, Walter A; Hollander, John M

    2015-02-01

    Mitofilin, also known as heart muscle protein, is an inner mitochondrial membrane structural protein that plays a central role in maintaining cristae morphology and structure. It is a critical component of the mitochondrial contact site and cristae organizing system (MICOS) complex which is important for mitochondrial architecture and cristae morphology. Our laboratory has previously reported alterations in mitochondrial morphology and proteomic make-up during type 1 diabetes mellitus, with mitofilin being significantly down-regulated in interfibrillar mitochondria (IFM). The goal of this study was to investigate whether overexpression of mitofilin can limit mitochondrial disruption associated with the diabetic heart through restoration of mitochondrial morphology and function. A transgenic mouse line overexpressing mitofilin was generated and mice injected intraperitoneally with streptozotocin using a multi low-dose approach. Five weeks following diabetes mellitus onset, cardiac contractile function was assessed. Restoration of ejection fraction and fractional shortening was observed in mitofilin diabetic mice as compared to wild-type controls (Pcomplex I, III, IV and V activities, state 3 respiration, lipid peroxidation as well as mitochondria membrane potential in type 1 diabetic IFM were restored in mitofilin diabetic mice (Pcomplexity using flow cytometry displayed significant reduction in internal complexity in diabetic IFM which was restored in mitofilin diabetic IFM (P<0.05). Taken together these results suggest that transgenic overexpression of mitofilin preserves mitochondrial structure, leading to restoration of mitochondrial function and attenuation of cardiac contractile dysfunction in the diabetic heart. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. BRCA1-IRIS overexpression promotes formation of aggressive breast cancers.

    Directory of Open Access Journals (Sweden)

    Yoshiko Shimizu

    Full Text Available INTRODUCTION: Women with HER2(+ or triple negative/basal-like (TN/BL breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2(+ and/or TN/BL tumors. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemical staining of large cohort of human breast tumor samples using new monoclonal anti-BRCA1-IRIS antibody, followed by correlation of BRCA1-IRIS expression with that of AKT1, AKT2, p-AKT, survivin and BRCA1/p220, tumor status and age at diagnosis. Generation of subcutaneous tumors in SCID mice using human mammary epithelial (HME cells overexpressing TERT/LT/BRCA1-IRIS, followed by comparing AKT, survivin, and BRCA1/p220 expression, tumor status and aggressiveness in these tumors to that in tumors developed using TERT/LT/Ras(V12-overexpressing HME cells. Induction of primary and invasive rat mammary tumors using the carcinogen N-methyl-N-nitrosourea (NMU, followed by analysis of rat BRCA1-IRIS and ERα mRNA levels in these tumors. High BRCA1-IRIS expression was detected in the majority of human breast tumors analyzed, which was positively correlated with that of AKT1-, AKT2-, p-AKT-, survivin, but negatively with BRCA1/p220 expression. BRCA1-IRIS-positivity induced high-grade, early onset and metastatic HER2(+ or TN/BL tumors. TERT/LT/BRCA1-IRIS overexpressing HME cells formed invasive subcutaneous tumors that express high AKT1, AKT2, p-AKT and vimentin, but no CK19, p63 or BRCA1/p220. NMU-induced primary and invasive rat breast cancers expressed high levels of rat BRCA1-IRIS mRNA but low levels of rat ERα mRNA. CONCLUSION/SIGNIFICANCE: BRCA1-IRIS overexpression triggers aggressive

  6. Overexpression of M3 Muscarinic Receptor Suppressed Adverse Electrical Remodeling in Hypertrophic Myocardium Via Increasing Repolarizing K+ Currents

    Directory of Open Access Journals (Sweden)

    Xue Chen

    2017-09-01

    Full Text Available Background/Aims: Cardiac hypertrophy (CH is an adaptive response to diverse cardiovascular conditions, which is accompanied by adverse electrical remodeling manifested as abnormal K+ channel activities. M3 subtype of muscarinic acetylcholine receptor (M3-mAChR is a novel regulator of cardiac electrical activity. In this study we aim to explore if the overexpression of M3-mAChR could attenuate the adverse electrical remodeling in CH and then uncover its underlying electrophysiological mechanisms. Methods: Transgenic mice with M3-mAChR overexpression (M3-TG and wild type (WT mice were subjected to transverse aortic constriction (TAC to induce CH. Myocardial hypertrophy and cardiac function were quantified by the measurement of echocardiography, electrocardiogram, heart weight and tibia length. Whole-cell and signal-cell patch-clamp were employed to record electrophysiological properties by acute isolation of acutely isolated ventricular cardiomyocytes and Western blot was carried out to evaluate the Kir2.1and Kv4.2/4.3 protein levels in left ventricular tissue. Results: Compared with WT group, the elevation of cardiac index, including heart weight/body weight index and heart weight/tibia length index confirmed the myocardial hypertrophic growth induced by TAC. Echocardiography detection revealed that the TAC-treated mice showed an obvious increase in the thickness of left ventricular posterior wall (LVPW and ejection fraction (EF due to compensatory hypertrophy, which attenuated by the overexpression of M3-mAChR. Pressure overload induced a prolongation of QTc interval in WT mice, an effect blunted in M3-TG mice. Furthermore, compared with WT mice, M3-mAChR overexpression in hypertrophic myocardium accelerated cardiac repolarization and shortened action potential duration, and thus correcting the prolongation of QTc interval. Moreover, M3-TG mice have the greater current density of IK1 and Ito in ventricular myocytes after TAC compared with WT

  7. Intestine-specific overexpression of IL-10 improves survival in polymicrobial sepsis.

    Science.gov (United States)

    Rajan, Saju; Vyas, Dinesh; Clark, Andrew T; Woolsey, Cheryl A; Clark, Jessica A; Hotchkiss, Richard S; Buchman, Timothy G; Coopersmith, Craig M

    2008-04-01

    Targeted IL-10 therapy improves survival in preclinical models of critical illness, and intestine-specific IL-10 decreases inflammation in models of chronic Inflammatory disease. We therefore sought to determine whether intestine-specific overexpression of IL-10 would improve survival in sepsis. Transgenic mice that overexpress IL-10 in their gut epithelium (Fabpi-IL-10 mice) and wild-type (WT) littermates (n = 127) were subjected to cecal ligation and puncture with a 27-gauge needle. The 7-day survival rate was 45% in transgenic animals and 30% in WT animals (P < or = 0.05). Systemic levels of IL-10 were undetectable in both groups of animals under basal conditions and were elevated to a similar degree in septic animals regardless of whether they expressed the transgene. Local parameter of injury, including gut epithelial apoptosis, intestinal permeability, peritoneal lavage cytokines, and stimulated cytokines from intraepithelial lymphocytes, were similar between transgenic and WT mice. However, in stimulated splenocytes, proinflammatory cytokines monocyte chemoattractant protein 1 (189 +/- 43 vs. 40 +/- 8 pg/mL) and IL-6 (116 +/- 28 vs. 34 +/- 9 pg/mL) were lower in Fabpi-IL-10 mice than WT littermates despite the intestine-specific nature of the transgene (P < 0.05). Cytokine levels were similar in blood and bronchoalveolar lavage fluid between the 2 groups, as were circulating LPS levels. Transgenic mice also had lower white blood cell counts associated with lower absolute neutrophil counts (0.5 +/- 0.1 vs. 1.0 +/- 0.2 10(3)/mm3; P < 0.05). These results indicate that gut-specific overexpression of IL-10 improves survival in a murine model of sepsis, and interactions between the intestinal epithelium and the systemic immune system may play a role in conferring this survival advantage.

  8. Cardiac FKBP12.6 overexpression protects against triggered ventricular tachycardia in pressure overloaded mouse hearts.

    Science.gov (United States)

    Vinet, Laurent; Pezet, Mylène; Bito, Virginie; Briec, François; Biesmans, Liesbeth; Rouet-Benzineb, Patricia; Gellen, Barnabas; Prévilon, Miresta; Chimenti, Stefano; Vilaine, Jean-Paul; Charpentier, Flavien; Sipido, Karin R; Mercadier, Jean-Jacques

    2012-03-01

    Alterations in RyR2 function have been proposed as a major pathophysiological mechanism of arrhythmias and heart failure (HF). Cardiac FKBP12.6 overexpression protects against myocardial infarction-induced HF and catecholamine-promoted ventricular arrhythmias. We tested the hypothesis that FKBP12.6 overexpression protects against maladaptive LVH and triggered ventricular arrhythmias following transverse aorta constriction (TAC) in the mouse. The TAC-associated mortality rate was significantly lower in male transgenic (DT) than in Ctr mice (p < 0.05). TAC-associated maladaptive hypertrophy was blunted in DT mice especially 1 month post-TAC and their SERCA2a/PLB ratio remained unchanged 1 and 2 months post-TAC. Two months after TAC, trains of 30 stimuli (burst pacing) performed following isoproterenol injection (0.2 mg/kg, ip), induced VT in 50% of the TAC-Ctr and in none of the TAC-DT mice (p = 0.022). The increase in myocyte shortening and Ca(2+) spark frequency observed in sham-operated Ctr mice in response to 50 nM isoproterenol was reduced in DT mice, and abolished in TAC-DT mice. NCX1 function was reduced in Sham-DT and TAC-DT compared with Sham-Ctr and TAC-Ctr mice, respectively (p < 0.05 for the 2 comparisons). In mice killed after isoproterenol injection and burst pacing, RyR2 S2814 phosphorylation was decreased by 50% in TAC-DT versus TAC-Ctr mice (p < 0.05), with no change in RyR2 S2808 and PLB S16 and T17 phosphorylation. Cardiac FKBP12.6 overexpression in the mouse blunts pressure overload-induced maladaptive LV remodelling and protects against catecholamine-promoted burst pacing-induced ventricular tachycardia by decreasing cardiac sensitivity to adrenergic stress and RyR2 S2814 phosphorylation, and decreasing NCX1 activity.

  9. Overexpression of constitutively active MAP3K7 in ameloblasts causes enamel defects of mouse teeth.

    Science.gov (United States)

    Jinping, Zhao; Qing, Chu; Wenying, Song; Chunyan, Yang; Lili, Xiang; Yao, Shi; Yumin, Wang; Zhenzhen, Xu; Li, Zhang; Yuguang, Gao

    2017-12-01

    Compelling evidence suggests that mitogen-activated protein kinases (Mapks) play an important role in amelogenesis. However, the role of transforming growth factor (TGF)-β-activating kinase 1 (Tak1, Map3k7), which is a known upstream kinase of Mapks, during amelogenesis remains to be determined. The aim of this study was to investigate the possible involvement of Map3k7 in amelogenesis. We generated transgenic mice that produced constitutively active human MAP3K7 (caMAP3K7) under the control of amelogenin (Amelx) gene promoter. Radiography and micro-computed tomography (μCT) analysis was used to detect the radio-opacity and density of the teeth. The enamel microstructure was observed with a scanning electron microscope. Histological analysis was used to observe the adhesion between ameloblasts and residual organic matrix of the enamel. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze the expression of enamel matrix protein. The enamel of mandibular molars in caMAP3K7-overexpressing mice displayed pigmentation and a highly irregular structure compared with the wild type littermates. Teeth of transgenic animals underwent rapid attrition due to the brittleness of the enamel layer. The microstructure of enamel, normally a highly ordered arrangement of hydroxyapatite crystals, was completely disorganized. The gross histological appearances of ameloblasts and supporting cellular structures, as well as the expression of the enamel protein amelotin (Amtn) were altered by the overexpression of caMAP3K7. Our data demonstrated that protein expression, processing and secretion occurred abnormally in transgenic mice overexpressing caMAP3K7. The overexpression of caMAP3K7 had a profound effect on enamel structure by disrupting the orderly growth of enamel prisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. A MAPP Network Study: Overexpression of Tumor Necrosis Factor-α in Mouse Urothelium Mimics Interstitial Cystitis.

    Science.gov (United States)

    Yang, Wenbin; Searl, Timothy J; Yaggie, Ryan E; Schaeffer, Anthony J; Klumpp, David J

    2018-02-21

    Interstitial cystitis/ bladder pain syndrome (IC/BPS) is a chronic bladder condition associated with pain and voiding dysfunction that is often regarded as a neurogenic cystitis. Patient symptoms are correlated with the presence of urothelial lesions. We previously characterized a murine neurogenic cystitis model that recapitulates mast cell accumulation and urothelial lesions, and these events were dependent upon TNF. To further explore the role of TNF in bladder inflammation and function, we generated a transgenic mouse model with chronic TNF overexpression in urothelium under the control of the uroplakin II (UPII) promoter. Transgenic mouse lines were maintained by backcross onto wild-type C57BL/6J mice, and evaluated for pelvic tactile allodynia as a measure of visceral pain, urinary function and urothelial lesions. TNF mRNA and protein were expressed at greater levels in bladders of UPII-TNF mice than wild type. UPII-TNF mice showed significantly increased urinary frequency and decreased void volume. UPII-TNF mice had increased urothelial apoptosis and loss of urothelial integrity consistent with urothelial lesions. Overexpression of TNF was also associated with pelvic tactile allodynia. Consistent with these findings UPII-TNF mice exhibited increased bladder afferents activity in response to stretch ex vivo. In summary, UPII-TNF mice display significant pelvic pain, voiding dysfunction, urothelial lesions and sensory input. Thus UPII-TNF mice are a novel model for characterizing mechanisms of IC symptoms and evaluating therapies.

  11. Significance of Aurora B overexpression in hepatocellular carcinoma. Aurora B Overexpression in HCC

    International Nuclear Information System (INIS)

    Lin, Zhong-Zhe; Jeng, Yung-Ming; Hu, Fu-Chang; Pan, Hung-Wei; Tsao, Hsin-Wei; Lai, Po-Lin; Lee, Po-Huang; Cheng, Ann-Lii; Hsu, Hey-Chi

    2010-01-01

    To investigate the significance of Aurora B expression in hepatocellular carcinoma (HCC). The Aurora B and Aurora A mRNA level was measured in 160 HCCs and the paired nontumorous liver tissues by reverse transcription-polymerase chain reaction. Mutations of the p53 and β-catenin genes were analyzed in 134 and 150 tumors, respectively, by direct sequencing of exon 2 to exon 11 of p53 and exon 3 of β-catenin. Anticancer effects of AZD1152-HQPA, an Aurora B kinase selective inhibitor, were examined in Huh-7 and Hep3B cell lines. Aurora B was overexpressed in 98 (61%) of 160 HCCs and in all 7 HCC cell lines examined. The overexpression of Aurora B was associated with Aurora A overexpression (P = 0.0003) and p53 mutation (P = 0.002) and was inversely associated with β-catenin mutation (P = 0.002). Aurora B overexpression correlated with worse clinicopathologic characteristics. Multivariate analysis confirmed that Aurora B overexpression was an independent poor prognostic factor, despite its interaction with Aurora A overexpression and mutations of p53 and β-catenin. In Huh-7 and Hep3B cells, AZD1152-HQPA induced proliferation blockade, histone H3 (Ser10) dephosphorylation, cell cycle disturbance, and apoptosis. Aurora B overexpression is an independent molecular marker predicting tumor invasiveness and poor prognosis of HCC. Aurora B kinase selective inhibitors are potential therapeutic agents for HCC treatment

  12. Interleukin 10 overexpression alters survival in the setting of gram-negative pneumonia following lung contusion.

    Science.gov (United States)

    Dolgachev, Vladislav A; Yu, Bi; Sun, Lei; Shanley, Thomas P; Raghavendran, Krishnan; Hemmila, Mark R

    2014-04-01

    Lung contusion injury produces a vulnerable window within the inflammatory defenses of the lung that predisposes the patient to pneumonia. Interleukin 10 (IL-10) is a known anti-inflammatory mediator produced by macrophages and capable of downregulating acute lung inflammation. We investigated the impact of increased levels of IL-10 within the lung on survival and the host response to trauma in the setting of lung contusion (LC) and gram-negative pneumonia. A bitransgenic, tetracycline-inducible, lung-specific human IL-10 overexpression (IL-10 OE) mouse model and single transgenic (TG-) control mice were used. Mice underwent LC injury or sham injury (sham) at time -6 h. At time 0, animals were inoculated intratracheally with 500 colony-forming units of Klebsiella pneumoniae (pneu). Bronchoalveolar lavage fluid, lung tissue specimens, or purified macrophages were collected. Lung tissue and blood bacteria levels were quantified. Cytokine levels were assayed by enzyme-linked immunosorbent assay, and gene expression levels were evaluated by real-time polymerase chain reaction. Cell-type identification and quantification were done using real-time polymerase chain reaction and flow cytometry. Interleukin 10 OE mice demonstrated decreased 5-day survival compared with TG- mice following LC + pneu (0 vs. 30%, P pneu animals (P < 0.05). Lung-specific IL-10 overexpression induces alternative activation of alveolar macrophages. This shift in macrophage phenotype decreases intracellular bacterial killing, resulting in a more pronounced bacteremia and accelerated mortality in a model of LC and pneumonia.

  13. 100-fold but not 50-fold dystrophin overexpression aggravates electrocardiographic defects in the mdx model of Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Yongping Yue

    2016-01-01

    Full Text Available Dystrophin gene replacement holds the promise of treating Duchenne muscular dystrophy. Supraphysiological expression is a concern for all gene therapy studies. In the case of Duchenne muscular dystrophy, Chamberlain and colleagues found that 50-fold overexpression did not cause deleterious side effect in skeletal muscle. To determine whether excessive dystrophin expression in the heart is safe, we studied two lines of transgenic mdx mice that selectively expressed a therapeutic minidystrophin gene in the heart at 50-fold and 100-fold of the normal levels. In the line with 50-fold overexpression, minidystrophin showed sarcolemmal localization and electrocardiogram abnormalities were corrected. However, in the line with 100-fold overexpression, we not only detected sarcolemmal minidystrophin expression but also observed accumulation of minidystrophin vesicles in the sarcoplasm. Excessive minidystrophin expression did not correct tachycardia, a characteristic feature of Duchenne muscular dystrophy. Importantly, several electrocardiogram parameters (QT interval, QRS duration and the cardiomyopathy index became worse than that of mdx mice. Our data suggests that the mouse heart can tolerate 50-fold minidystrophin overexpression, but 100-fold overexpression leads to cardiac toxicity.

  14. Overexpression of homogentisate phytyltransferase in lettuce results ...

    African Journals Online (AJOL)

    Administrator

    2011-10-19

    Oct 19, 2011 ... gene and the total content of α and γ-tocopherol in transgenic plants were increased up to 4 and 2.61 folds, respectively, demonstrating that overexpression of HPT gene is an effective way to improve vitamin E content in lettuce. Key words: Lactuca sativa, tocopherol, homogentisate phytyltransferase (HPT), ...

  15. Overexpression of Protective Antigen as a Novel Approach To Enhance Vaccine Efficacy of Brucella abortus Strain RB51

    Science.gov (United States)

    Vemulapalli, Ramesh; He, Yongqun; Cravero, Silvio; Sriranganathan, Nammalwar; Boyle, Stephen M.; Schurig, Gerhardt G.

    2000-01-01

    Brucella abortus strain RB51 is an attenuated rough strain that is currently being used as the official live vaccine for bovine brucellosis in the United States and several other countries. We reasoned that overexpression of a protective antigen(s) of B. abortus in strain RB51 should enhance its vaccine efficacy. To test this hypothesis, we overexpressed Cu/Zn superoxide dismutase (SOD) protein of B. abortus in strain RB51. This was accomplished by transforming strain RB51 with a broad-host-range plasmid, pBBR1MCS, containing the sodC gene along with its promoter. Strain RB51 overexpressing SOD (RB51SOD) was tested in BALB/c mice for its ability to protect against challenge infection with virulent strain 2308. Mice vaccinated with RB51SOD, but not RB51, developed antibodies and cell-mediated immune responses to Cu/Zn SOD. Strain RB51SOD vaccinated mice developed significantly (P RB51 alone. The presence of the plasmid alone in strain RB51 did not alter its vaccine efficacy. Also, overexpression of SOD did not alter the attenuation characteristic of strain RB51. PMID:10816475

  16. Overexpression of dimethylarginine dimethylaminohydrolase 1 attenuates airway inflammation in a mouse model of asthma.

    Directory of Open Access Journals (Sweden)

    Kayla G Kinker

    Full Text Available Levels of asymmetric dimethylarginine (ADMA, an endogenous inhibitor of nitric oxide synthase, are increased in lung, sputum, exhaled breath condensate and plasma samples from asthma patients. ADMA is metabolized primarily by dimethylarginine dimethylaminohydrolase 1 (DDAH1 and DDAH2. We determined the effect of DDAH1 overexpression on development of allergic inflammation in a mouse model of asthma. The expression of DDAH1 and DDAH2 in mouse lungs was determined by RT-quantitative PCR (qPCR. ADMA levels in bronchoalveolar lavage fluid (BALF and serum samples were determined by mass spectrometry. Wild type and DDAH1-transgenic mice were intratracheally challenged with PBS or house dust mite (HDM. Airway inflammation was assessed by bronchoalveolar lavage (BAL total and differential cell counts. The levels of IgE and IgG1 in BALF and serum samples were determined by ELISA. Gene expression in lungs was determined by RNA-Seq and RT-qPCR. Our data showed that the expression of DDAH1 and DDAH2 was decreased in the lungs of mice following HDM exposure, which correlated with increased ADMA levels in BALF and serum. Transgenic overexpression of DDAH1 resulted in decreased BAL total cell and eosinophil numbers following HDM exposure. Total IgE levels in BALF and serum were decreased in HDM-exposed DDAH1-transgenic mice compared to HDM-exposed wild type mice. RNA-Seq results showed downregulation of genes in the inducible nitric oxide synthase (iNOS signaling pathway in PBS-treated DDAH1-transgenic mice versus PBS-treated wild type mice and downregulation of genes in IL-13/FOXA2 signaling pathway in HDM-treated DDAH1-transgenic mice versus HDM-treated wild type mice. Our findings suggest that decreased expression of DDAH1 and DDAH2 in the lungs may contribute to allergic asthma and overexpression of DDAH1 attenuates allergen-induced airway inflammation through modulation of Th2 responses.

  17. Hand1 overexpression inhibits medulloblastoma metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Asuthkar, Swapna; Guda, Maheedhara R. [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Martin, Sarah E. [Department of Pathology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Antony, Reuben; Fernandez, Karen [Department of Pediatrics, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Lin, Julian [Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Tsung, Andrew J. [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Illinois Neurological Institute, Peoria, IL 61656 (United States); Velpula, Kiran K., E-mail: velpula@uic.edu [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States)

    2016-08-19

    Medulloblastoma (MB) is the most frequent malignant pediatric brain tumor. Current treatment includes surgery, radiation and chemotherapy. However, ongoing treatment in patients is further classified according to the presence or absence of metastasis. Since metastatic medulloblastoma are refractory to current treatments, there is need to identify novel biomarkers that could be used to reduce metastatic potential, and more importantly be targeted therapeutically. Previously, we showed that ionizing radiation-induced uPAR overexpression is associated with increased accumulation of β-catenin in the nucleus. We further demonstrated that uPAR protein act as cytoplasmic sequestration factor for a novel basic helix-loop-helix transcription factor, Hand1. Among the histological subtypes classical and desmoplastic subtypes account for the majority while large cell/anaplastic variant is most commonly associated with metastatic disease. In this present study using immunohistochemical approach and patient data mining for the first time, we demonstrated that Hand1 expression is observed to be downregulated in all the subtypes of medulloblastoma. Previously we showed that Hand1 overexpression regulated medulloblastoma angiogenesis and here we investigated the role of Hand1 in the context of Epithelial-Mesenchymal Transition (EMT). Moreover, UW228 and D283 cells overexpressing Hand1 demonstrated decreased-expression of mesenchymal markers (N-cadherin, β-catenin and SOX2); metastatic marker (SMA); and increased expression of epithelial marker (E-cadherin). Strikingly, human pluripotent stem cell antibody array showed that Hand1 overexpression resulted in substantial decrease in pluripotency markers (Nanog, Oct3/4, Otx2, Flk1) suggesting that Hand1 expression may be essential to attenuate the EMT and our findings underscore a novel role for Hand1 in medulloblastoma metastasis. - Highlights: • Hand1 expression is downregulated in Medulloblastoma. • Hand1 over expression reduce

  18. Hand1 overexpression inhibits medulloblastoma metastasis

    International Nuclear Information System (INIS)

    Asuthkar, Swapna; Guda, Maheedhara R.; Martin, Sarah E.; Antony, Reuben; Fernandez, Karen; Lin, Julian; Tsung, Andrew J.; Velpula, Kiran K.

    2016-01-01

    Medulloblastoma (MB) is the most frequent malignant pediatric brain tumor. Current treatment includes surgery, radiation and chemotherapy. However, ongoing treatment in patients is further classified according to the presence or absence of metastasis. Since metastatic medulloblastoma are refractory to current treatments, there is need to identify novel biomarkers that could be used to reduce metastatic potential, and more importantly be targeted therapeutically. Previously, we showed that ionizing radiation-induced uPAR overexpression is associated with increased accumulation of β-catenin in the nucleus. We further demonstrated that uPAR protein act as cytoplasmic sequestration factor for a novel basic helix-loop-helix transcription factor, Hand1. Among the histological subtypes classical and desmoplastic subtypes account for the majority while large cell/anaplastic variant is most commonly associated with metastatic disease. In this present study using immunohistochemical approach and patient data mining for the first time, we demonstrated that Hand1 expression is observed to be downregulated in all the subtypes of medulloblastoma. Previously we showed that Hand1 overexpression regulated medulloblastoma angiogenesis and here we investigated the role of Hand1 in the context of Epithelial-Mesenchymal Transition (EMT). Moreover, UW228 and D283 cells overexpressing Hand1 demonstrated decreased-expression of mesenchymal markers (N-cadherin, β-catenin and SOX2); metastatic marker (SMA); and increased expression of epithelial marker (E-cadherin). Strikingly, human pluripotent stem cell antibody array showed that Hand1 overexpression resulted in substantial decrease in pluripotency markers (Nanog, Oct3/4, Otx2, Flk1) suggesting that Hand1 expression may be essential to attenuate the EMT and our findings underscore a novel role for Hand1 in medulloblastoma metastasis. - Highlights: • Hand1 expression is downregulated in Medulloblastoma. • Hand1 over expression reduce

  19. Cardiac-Specific Overexpression of Catalase Attenuates Lipopolysaccharide-Induced Myocardial Contractile Dysfunction: Role of Autophagy

    Science.gov (United States)

    Turdi, Subat; Han, Xuefeng; Huff, Anna F.; Roe, Nathan D.; Hu, Nan; Gao, Feng; Ren, Jun

    2012-01-01

    Lipopolysaccharide (LPS) from Gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complication in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged with LPS (6 mg/kg) and cardiac function was evaluated. Levels of oxidative stress, autophagy, apoptosis and protein damage were examined using fluorescence microscopy, Western blot, TUNEL assay, caspase-3 activity and carbonyl formation. Kaplan-Meier curve was constructed for survival following LPS treatment. Our results revealed a lower mortality in catalase mice compared with FVB mice following LPS challenge. LPS injection led to depressed cardiac contractile capacity as evidenced by echocardiography and cardiomyocyte contractile function, the effect of which was ablated by catalase overexpression. LPS treatment induced elevated TNF-α level, autophagy, apoptosis (TUNEL, caspase-3 activation, cleaved caspase-3), production of ROS and O2−, and protein carbonyl formation, the effects of which were significantly attenuated by catalase overexpression. Electron microscopy revealed focal myocardial damage characterized by mitochondrial injury following LPS treatment, which was less severe in catalase mice. Interestingly, LPS-induced cardiomyocyte contractile dysfunction was prevented by antioxidant NAC and the autophagy inhibitor 3-methyladenine. Taken together, our data revealed that catalase protects against LPS-induced cardiac dysfunction and mortality, which may be associated with inhibition of oxidative stress and autophagy. PMID:22902401

  20. Cardiac-specific overexpression of catalase attenuates lipopolysaccharide-induced myocardial contractile dysfunction: role of autophagy.

    Science.gov (United States)

    Turdi, Subat; Han, Xuefeng; Huff, Anna F; Roe, Nathan D; Hu, Nan; Gao, Feng; Ren, Jun

    2012-09-15

    Lipopolysaccharide (LPS) from gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complications in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged with LPS (6 mg/kg) and cardiac function was evaluated. Levels of oxidative stress, autophagy, apoptosis, and protein damage were examined using fluorescence microscopy, Western blot, TUNEL assay, caspase-3 activity, and carbonyl formation. A Kaplan-Meier curve was constructed for survival after LPS treatment. Our results revealed a lower mortality in catalase mice compared with FVB mice after LPS challenge. LPS injection led to depressed cardiac contractile capacity as evidenced by echocardiography and cardiomyocyte contractile function, the effect of which was ablated by catalase overexpression. LPS treatment induced elevated TNF-α level, autophagy, apoptosis (TUNEL, caspase-3 activation, cleaved caspase-3), production of ROS and O(2)(-), and protein carbonyl formation, the effects of which were significantly attenuated by catalase overexpression. Electron microscopy revealed focal myocardial damage characterized by mitochondrial injury after LPS treatment, which was less severe in catalase mice. Interestingly, LPS-induced cardiomyocyte contractile dysfunction was prevented by the antioxidant N-acetylcysteine and the autophagy inhibitor 3-methyladenine. Taken together, our data revealed that catalase protects against LPS-induced cardiac dysfunction and mortality, which may be associated with inhibition of oxidative stress and autophagy. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Leptin Overexpression in Bone Marrow Stromal Cells Promotes Periodontal Regeneration in a Rat Model of Osteoporosis.

    Science.gov (United States)

    Zheng, Baoyu; Jiang, Jun; Chen, Yuling; Lin, Minkui; Du, Zhibin; Xiao, Yin; Luo, Kai; Yan, Fuhua

    2017-08-01

    Osteoporosis is associated with widespread periodontitis and impaired periodontal healing. However, there is a lack of information about the outcomes of regenerative approaches under the influence of osteoporosis. This study investigates the effect of leptin (LEP) overexpression on the regenerative potential of bone marrow stromal cells (BMSCs) in an osteoporotic rat periodontal fenestration defect model. Rat BMSCs were transfected with adenoviruses harboring the human (h)LEP gene. Cell proliferation and osteogenic differentiation were evaluated. A β-tricalcium phosphate scaffold seeded with transfected cells was implanted into nude mice to investigate ectopic osteogenesis and into an osteoporotic rat defect to study periodontal regeneration. Regenerated periodontal and bone-like tissues were analyzed by histologic methods. hLEP overexpression induced osteogenic differentiation of BMSCs as evidenced by the upregulation of osteogenesis-related genes such as Runt-related transcription factor 2, alkaline phosphatase (ALP), and collagen Type I, as well as increased ALP activity and enhanced mineralization. Mice implanted with hLEP-BMSC-containing scaffolds showed more extensive formation of bone-like tissue than those in other groups. Periodontal defects were also filled to a greater degree when treated with hLEP-BMSCs and contained cementum and a well-organized periodontal ligament after 10 and 28 days. hLEP overexpression in BMSCs can stimulate periodontal regeneration in osteoporotic conditions and might be a promising strategy for periodontal regeneration in patients with osteoporosis.

  2. Impaired chemosensitivity of mouse dorsal raphe serotonergic neurons overexpressing serotonin 1A (Htr1a) receptors.

    Science.gov (United States)

    Baccini, Gilda; Mlinar, Boris; Audero, Enrica; Gross, Cornelius Thilo; Corradetti, Renato

    2012-01-01

    Serotonergic system participates in a wide range of physiological processes and behaviors, but its role is generally considered as modulatory and noncrucial, especially concerning life-sustaining functions. We recently created a transgenic mouse line in which a functional deficit in serotonin homeostasis due to excessive serotonin autoinhibition was produced by inducing serotonin 1A receptor (Htr1a) overexpression selectively in serotonergic neurons (Htr1a raphe-overexpressing or Htr1a(RO) mice). Htr1a(RO) mice exhibit episodes of autonomic dysregulation, cardiovascular crises and death, resembling those of sudden infant death syndrome (SIDS) and revealing a life-supporting role of serotonergic system in autonomic control. Since midbrain serotonergic neurons are chemosensitive and are implicated in arousal we hypothesized that their chemosensitivity might be impaired in Htr1a(RO) mice. Loose-seal cell-attached recordings in brainstem slices revealed that serotonergic neurons in dorsal raphe nucleus of Htr1a(RO) mice have dramatically reduced responses to hypercapnic challenge as compared with control littermates. In control mice, application of 9% CO(2) produced an increase in firing rate of serotonergic neurons (0.260 ± 0.041 Hz, n=20, p=0.0001) and application of 3% CO(2) decreased their firing rate (-0.142 ± 0.025 Hz, n=17, p=0.0008). In contrast, in Htr1a(RO) mice, firing rate of serotonergic neurons was not significantly changed by 9% CO(2) (0.021 ± 0.034 Hz, n=16, p=0.49) and by 3% CO(2) (0.012 ± 0.046 Hz, n=12, p=0.97). Our findings support the hypothesis that chemosensitivity of midbrain serotonergic neurons provides a physiological mechanism for arousal responses to life-threatening episodes of hypercapnia and that functional impairment, such as excessive autoinhibition, of midbrain serotonergic neuron responses to hypercapnia may contribute to sudden death.

  3. Nitric Oxide Synthase Type III Overexpression By Gene Therapy Exerts Antitumoral Activity In Mouse Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Raúl González

    2015-08-01

    Full Text Available Hepatocellular carcinoma develops in cirrhotic liver. The nitric oxide (NO synthase type III (NOS-3 overexpression induces cell death in hepatoma cells. The study developed gene therapy designed to specifically overexpress NOS-3 in cultured hepatoma cells, and in tumors derived from orthotopically implanted tumor cells in fibrotic livers. Liver fibrosis was induced by CCl4 administration in mice. Hepa 1-6 cells were used for in vitro and in vivo experiments. The first generation adenovirus was designed to overexpress NOS-3 (or GFP and luciferase cDNA under the regulation of murine alpha-fetoprotein (AFP and Rous Sarcoma Virus (RSV promoters, respectively. Both adenoviruses were administered through the tail vein two weeks after orthotopic tumor cell implantation. AFP-NOS-3/RSV-Luciferase increased oxidative-related DNA damage, p53, CD95/CD95L expression and caspase-8 activity in cultured Hepa 1-6 cells. The increased expression of CD95/CD95L and caspase-8 activity was abolished by l-NAME or p53 siRNA. The tail vein infusion of AFP-NOS- 3/RSV-Luciferase adenovirus increased cell death markers, and reduced cell proliferation of established tumors in fibrotic livers. The increase of oxidative/nitrosative stress induced by NOS-3 overexpression induced DNA damage, p53, CD95/CD95L expression and cell death in hepatocellular carcinoma cells. The effectiveness of the gene therapy has been demonstrated in vitro and in vivo.

  4. p130Cas over-expression impairs mammary branching morphogenesis in response to estrogen and EGF.

    Directory of Open Access Journals (Sweden)

    Maria del Pilar Camacho Leal

    Full Text Available p130Cas adaptor protein regulates basic processes such as cell cycle control, survival and migration. p130Cas over-expression has been related to mammary gland transformation, however the in vivo consequences of p130Cas over-expression during mammary gland morphogenesis are not known. In ex vivo mammary explants from MMTV-p130Cas transgenic mice, we show that p130Cas impairs the functional interplay between Epidermal Growth Factor Receptor (EGFR and Estrogen Receptor (ER during mammary gland development. Indeed, we demonstrate that p130Cas over-expression upon the concomitant stimulation with EGF and estrogen (E2 severely impairs mammary morphogenesis giving rise to enlarged multicellular spherical structures with altered architecture and absence of the central lumen. These filled acinar structures are characterized by increased cell survival and proliferation and by a strong activation of Erk1/2 MAPKs and Akt. Interestingly, antagonizing the ER activity is sufficient to re-establish branching morphogenesis and normal Erk1/2 MAPK activity. Overall, these results indicate that high levels of p130Cas expression profoundly affect mammary morphogenesis by altering epithelial architecture, survival and unbalancing Erk1/2 MAPKs activation in response to growth factors and hormones. These results suggest that alteration of morphogenetic pathways due to p130Cas over-expression might prime mammary epithelium to tumorigenesis.

  5. Role of heparanase on hepatic uptake of intestinal derived lipoprotein and fatty streak formation in mice.

    Directory of Open Access Journals (Sweden)

    David Planer

    Full Text Available BACKGROUND: Heparanase modulates the level of heparan sulfate proteoglycans (HSPGs which have an important role in multiple cellular processes. Recent studies indicate that HSPGs have an important function in hepatic lipoprotein handling and processes involving removal of lipoprotein particles. PRINCIPAL FINDINGS: To determine the effects of decreased HSPGs chain length on lipoprotein metabolism and atherosclerosis, transgenic mice over-expressing the human heparanase gene were studied. Hepatic lipid uptake in hpa-Tg mice were evaluated by giving transgenic mice oral fat loads and labeled retinol. Sections of aorta from mice over-expressing heparanase (hpa-Tg and controls (C57/BL6 fed an atherogenic diet were examined for evidence of atherosclerosis. Heparanase over-expression results in reduced hepatic clearance of postprandial lipoproteins and higher levels of fasting and postprandial serum triglycerides. Heparanase over-expression also induces formation of fatty streaks in the aorta. The mean lesion cross-sectional area in heparanase over-expressing mice was almost 6 times higher when compared to control mice (23,984 µm(2±5,922 vs. 4,189 µm(2±1,130, p<0.001. CONCLUSIONS: Over-expression of heparanase demonstrates the importance of HSPGs for the uptake of intestinal derived lipoproteins and its role in the formation of fatty streaks.

  6. Hyaluronic acid modified mesoporous carbon nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells

    Science.gov (United States)

    Wan, Long; Jiao, Jian; Cui, Yu; Guo, Jingwen; Han, Ning; Di, Donghua; Chang, Di; Wang, Pu; Jiang, Tongying; Wang, Siling

    2016-04-01

    In this paper, hyaluronic acid (HA) functionalized uniform mesoporous carbon spheres (UMCS) were synthesized for targeted enzyme responsive drug delivery using a facile electrostatic attraction strategy. This HA modification ensured stable drug encapsulation in mesoporous carbon nanoparticles in an extracellular environment while increasing colloidal stability, biocompatibility, cell-targeting ability, and controlled cargo release. The cellular uptake experiments of fluorescently labeled mesoporous carbon nanoparticles, with or without HA functionalization, demonstrated that HA-UMCS are able to specifically target cancer cells overexpressing CD44 receptors. Moreover, the cargo loaded doxorubicin (DOX) and verapamil (VER) exhibited a dual pH and hyaluronidase-1 responsive release in the tumor microenvironment. In addition, VER/DOX/HA-UMCS exhibited a superior therapeutic effect on an in vivo HCT-116 tumor in BALB/c nude mice. In summary, it is expected that HA-UMCS will offer a new method for targeted co-delivery of drugs to tumors overexpressing CD44 receptors.

  7. Frequent Nek1 overexpression in human gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun [School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai (China); Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Cai, Yu, E-mail: aihaozuqiu22@163.com [School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai (China); Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Liu, Pin [Med-X Research Institute, Shanghai Jiao Tong University, Shanghai (China); Zhao, Weiguo [Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

    2016-08-05

    Never in mitosis A (NIMA)-related kinase 1 (Nek1) regulates cell cycle progression to mitosis. Its expression and potential functions in human gliomas have not been studied. Here, our immunohistochemistry (IHC) assay and Western blot assay results showed that Nek1 expression was significantly upregulated in fresh and paraffin-embedded human glioma tissues. Its level in normal brain tissues was low. Nek1 overexpression in human gliomas was correlated with the proliferation marker (Ki-67), tumor grade, Karnofsky performance scale (KPS) and more importantly, patients’ poor survival. Further studies showed that Nek1 expression level was also increased in multiple human glioma cell lines (U251-MG, U87-MG, U118, H4 and U373). Significantly, siRNA-mediated knockdown of Nek1 inhibited glioma cell (U87-MG/U251-MG) growth. Nek1 siRNA also sensitized U87-MG/U251-MG cells to temozolomide (TMZ), causing a profound apoptosis induction and growth inhibition. The current study indicates Nek1 might be a novel and valuable oncotarget of glioma, it is important for glioma cell growth and TMZ-resistance. - Highlights: • Nek1 is upregulated in multiple human glioma tissues and cell lines. • Nek1 overexpression correlates with glioma grades and patients’ KPS score. • Nek1 overexpression correlates with patients’ poor overall survival. • siRNA knockdown of Nek1 inhibits glioma cell growth. • siRNA knockdown of Nek1 sensitizes human glioma cells to temozolomide.

  8. Lack of cyclin D1 overexpression in gastric carcinogenesis

    NARCIS (Netherlands)

    Blok, P.; Craanen, M. E.; van Diest, P. J.; Dekker, W.; Tytgat, G. N.

    2000-01-01

    Cyclin D1 overexpression was examined in early gastric carcinomas and precursor lesions with the following aims; (1) to assess the chronology of cyclin D1 overexpression in various stages of gastric carcinogenesis, (2) to correlate cyclin D1 overexpression with the Lauren type, the grade of

  9. Overexpression of the mitochondrial T3 receptor induces skeletal muscle atrophy during aging.

    Directory of Open Access Journals (Sweden)

    François Casas

    2009-05-01

    Full Text Available In previous studies, we characterized a new hormonal pathway involving a mitochondrial T3 receptor (p43 acting as a mitochondrial transcription factor. In in vitro and in vivo studies, we have shown that p43 increases mitochondrial transcription and mitochondrial biogenesis. In addition, p43 overexpression in skeletal muscle stimulates mitochondrial respiration and induces a shift in metabolic and contractile features of muscle fibers which became more oxidative.Here we have studied the influence of p43 overexpression in skeletal muscle of mice during aging. We report that p43 overexpression initially increased mitochondrial mass. However, after the early rise in mitochondrial DNA occurring at 2 months of age in transgenic mice, we observed a progressive decrease of mitochondrial DNA content which became 2-fold lower at 23 months of age relatively to control animals. Moreover, p43 overexpression induced an oxidative stress characterized by a strong increase of lipid peroxidation and protein oxidation in quadriceps muscle, although antioxidant enzyme activities (catalase and superoxide dismutase were stimulated. In addition, muscle atrophy became detectable at 6 months of age, probably through a stimulation of the ubiquitin proteasome pathway via two muscle-specific ubiquitin ligases E3, Atrogin-1/MAFbx and MuRF1.Taken together, these results demonstrate that a prolonged stimulation of mitochondrial activity induces muscle atrophy. In addition, these data underline the importance of a tight control of p43 expression and suggest that a deregulation of the direct T3 mitochondrial pathway could be one of the parameters involved in the occurrence of sarcopenia.

  10. Myocardial overexpression of Mecr, a gene of mitochondrial FAS II leads to cardiac dysfunction in mouse.

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    Zhijun Chen

    Full Text Available It has been recently recognized that mammalian mitochondria contain most, if not all, of the components of fatty acid synthesis type II (FAS II. Among the components identified is 2-enoyl thioester reductase/mitochondrial enoyl-CoA reductase (Etr1/Mecr, which catalyzes the NADPH-dependent reduction of trans-2-enoyl thioesters, generating saturated acyl-groups. Although the FAS type II pathway is highly conserved, its physiological role in fatty acid synthesis, which apparently occurs simultaneously with breakdown of fatty acids in the same subcellular compartment in mammals, has remained an enigma. To study the in vivo function of the mitochondrial FAS in mammals, with special reference to Mecr, we generated mice overexpressing Mecr under control of the mouse metallothionein-1 promoter. These Mecr transgenic mice developed cardiac abnormalities as demonstrated by echocardiography in vivo, heart perfusion ex vivo, and electron microscopy in situ. Moreover, the Mecr transgenic mice showed decreased performance in endurance exercise testing. Our results showed a ventricular dilatation behind impaired heart function upon Mecr overexpression, concurrent with appearance of dysmorphic mitochondria. Furthermore, the data suggested that inappropriate expression of genes of FAS II can result in the development of hereditary cardiomyopathy.

  11. E2F1 activation is responsible for pituitary adenomas induced by HMGA2 gene overexpression

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    Fusco Alfredo

    2006-08-01

    Full Text Available Abstract The High Mobility Group protein HMGA2 is a nuclear architectural factor that plays a critical role in a wide range of biological processes including regulation of gene expression, embryogenesis and neoplastic transformation. Several studies are trying to identify the mechanisms by which HMGA2 protein is involved in each of these activities, and only recently some new significant insights are emerging from the study of transgenic and knock-out mice. Overexpression of HMGA2 gene leads to the onset of prolactin and GH-hormone induced pituitary adenomas in mice, suggesting a critical role of this protein in pituitary tumorigenesis. This was also confirmed in the human pathology by the finding that HMGA2 amplification and/or overexpression is present in human prolactinomas. This review focuses on recent data that explain the mechanism by which HMGA2 induces the development of pituitary adenomas in mice. This mechanism entails the activation of the E2F1 protein by the HMGA2-mediated displacement of HDAC1 from pRB protein.

  12. Ski overexpression in skeletal muscle modulates genetic programs that control susceptibility to diet-induced obesity and insulin signaling.

    Science.gov (United States)

    Diaz, Marianne; Martel, Nick; Fitzsimmons, Rebecca L; Eriksson, Natalie A; Cowin, Gary J; Thomas, Gethin P; Cao, Kim-Anh Lê; Muscat, George E O; Leong, Gary M

    2012-11-01

    Transgenic mice overexpressing chicken Ski (c-Ski) have marked decrease in adipose mass with skeletal muscle hypertrophy. Recent evidence indicates a role for c-Ski in lipogenesis and energy expenditure. In the present study, wild type (WT) and c-Ski mice were challenged on a high-fat (HF) diet to determine whether c-Ski mice were resistant to diet-induced obesity. During the HF feeding WT mice gained significantly more weight than chow-fed animals, while c-Ski mice were partially resistant to the effects of the HF diet on weight. Body composition analysis confirmed the decreased adipose mass in c-Ski mice compared to WT mice. c-Ski mice possess a similar metabolic rate and level of food consumption to WT littermates, despite lower activity levels and on chow diet show mild glucose intolerance relative to WT littermates. On HF diet, glucose tolerance surprisingly remained unchanged in c-Ski mice, while it became worse in WT mice. Skeletal muscle of c-Ski mice exhibit impaired insulin-stimulated Akt phosphorylation and glucose uptake. In concordance, gene expression profiling of skeletal muscle of chow and HF-fed mice indicated that Ski suppresses gene expression associated with insulin signaling and glucose uptake and alters gene pathways involved in myogenesis and adipogenesis. In conclusion, c-Ski mice are partially resistant to diet-induced obesity and display aberrant insulin signaling and glucose homeostasis which is associated with alterations in gene expression that inhibit lipogenesis and insulin signaling. These results suggest Ski plays a major role in skeletal muscle metabolism and adipogenesis and hence influences risk of obesity and diabetes.

  13. Overexpression of Heme Oxygenase-1 Prevents Renal Interstitial Inflammation and Fibrosis Induced by Unilateral Ureter Obstruction.

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    Xiao Chen

    Full Text Available Renal fibrosis plays an important role in the onset and progression of chronic kidney diseases. Many studies have demonstrated that heme oxygenase-1 (HO-1 is involved in diverse biological processes as a cytoprotective molecule, including anti-inflammatory, anti-oxidant, anti-apoptotic, antiproliferative, and immunomodulatory effects. However, the mechanisms of HO-1 prevention in renal interstitial fibrosis remain unknown. In this study, HO-1 transgenic (TG mice were employed to investigate the effect of HO-1 on renal fibrosis using a unilateral ureter obstruction (UUO model and to explore the potential mechanisms. We found that HO-1 was adaptively upregulated in kidneys of both TG and wild type (WT mice after UUO. The levels of HO-1 mRNA and protein were increased in TG mice compared with WT mice under normal conditions. HO-1 expression was further enhanced after UUO and remained high during the entire experimental process. Renal interstitial fibrosis in the TG group was significantly attenuated compared with that in the WT group after UUO. Moreover, overexpression of HO-1 inhibited the loss of peritubular capillaries. In addition, UUO-induced activation and proliferation of myofibroblasts were suppressed by HO-1 overexpression. Furthermore, HO-1 restrained tubulointerstitial infiltration of macrophages and regulated the secretion of inflammatory cytokines in UUO mice. We also found that high expression of HO-1 inhibited reactivation of Wnt/β-catenin signaling, which could play a crucial role in attenuating renal fibrosis. In conclusion, these data suggest that HO-1 prevents renal tubulointerstitial fibrosis possibly by regulating the inflammatory response and Wnt/β-catenin signaling. This study provides evidence that augmentation of HO-1 levels may be a therapeutic strategy against renal interstitial fibrosis.

  14. β‑catenin nuclear translocation induced by HIF‑1α overexpression leads to the radioresistance of prostate cancer.

    Science.gov (United States)

    Luo, Yong; Li, Mingchuan; Zuo, Xuemei; Basourakos, Spyridon P; Zhang, Jiao; Zhao, Jiahui; Han, Yili; Lin, Yunhua; Wang, Yongxing; Jiang, Yongguang; Lan, Ling

    2018-04-12

    Hypoxia-inducible factor‑1α (HIF‑1α) is known to play crucial roles in tumor radioresistance; however, the molecular mechanisms responsible for the promotion of tumor radioresistance by HIF‑1α remain unclear. β‑catenin is known to be involved in the metastatic potential of prostate cancer (PCa). In this study, to investigate the role of HIF‑1α and β‑catenin in the radioresistance of PCa, two PCa cell lines, LNCaP and C4‑2B, were grouped as follows: Negative control (no treatment), HIF‑1α overexpression group (transfected with HIF‑1α overexpression plasmid) and β‑catenin silenced group (transfected with HIF‑1α plasmids and β‑catenin-shRNA). Cell proliferation, cell cycle, cell invasion and radiosensitivity were examined under normal or hypoxic conditions. In addition, radiosensitivity was examined in two mouse PCa models (the LNCaP orthotopic BALB/c-nu mice model and the C4‑2B subcutaneous SCID mice model). Our results revealed that in both the LNCaP and C4‑2B cells, transfection with HIF‑1α overexpression plasmid led to an enhanced β‑catenin nuclear translocation, while β‑catenin silencing inhibited β‑catenin nuclear translocation. The enhanced β‑catenin nuclear translocation induced by HIF‑1α overexpression resulted in an enhanced cell proliferation and cell invasion, an altered cell cycle distribution, decreased apoptosis, and improved non‑homologous end joining (NHEJ) repair under normal and irradiation conditions. Similar results were observed in the animal models. HIF‑1α overexpression enhanced β‑catenin nuclear translocation, which led to the activation of the β‑catenin/NHEJ signaling pathway and increased cell proliferation, cell invasion and DNA repair. These results thus suggest that HIF‑1α overexpression promotes the radioresistance of PCa cells.

  15. FKBP12.6 overexpression does not protect against remodelling after myocardial infarction.

    Science.gov (United States)

    Bito, Virginie; Biesmans, Liesbeth; Gellen, Barnabas; Antoons, Gudrun; Macquaide, Niall; Rouet-Benzineb, Patricia; Pezet, Mylène; Mercadier, Jean-Jacques; Sipido, Karin R

    2013-01-01

    Reducing the open probability of the ryanodine receptor (RyR) has been proposed to have beneficial effects in heart failure. We investigated whether conditional FKBP12.6 overexpression at the time of myocardial infarction (MI) could improve cardiac remodelling and cell Ca(2+) handling. Wild-type (WT) mice and mice overexpressing FKBP12.6 (Tg) were studied on average 7.5 ± 0.2 weeks after MI and compared with sham-operated mice for in vivo, myocyte function and remodelling. At baseline, unloaded cell shortening in Tg was not different from WT. The [Ca(2+)](i) transient amplitude was similar, but sarcoplasmic reticulum (SR) Ca(2+) content was larger in Tg, suggesting reduced fractional release. Spontaneous spark frequency was similar despite the increased SR Ca(2+) content, consistent with a reduced RyR channel open probability in Tg. After MI, left ventricular dilatation and myocyte hypertrophy were present in both groups, but more pronounced in Tg. Cell shortening amplitude was unchanged with MI in WT, but increased with MI in Tg. The amplitude of the [Ca(2+)](i) transient was not affected by MI in either genotype, but time to peak was increased; this was most pronounced in Tg. The SR Ca(2+) content and Na(+)- Ca(2+) exchanger function were not affected by MI. Spontaneous spark frequency was increased significantly after MI in Tg, and larger than in WT (at 4 Hz, 2.6 ± 0.4 sparks (100 μm)(-1) s(-1) in Tg MI versus 1.6 ± 0.2 sparks (100 μm)(-1) s(-1) in WT MI; P < 0.05). We conclude that FKPB12.6 overexpression can effectively reduce RyR open probability with maintained cardiomyocyte contraction. However, this approach appears insufficient to prevent and reduce post-MI remodelling, indicating that additional pathways may need to be targeted.

  16. Overexpression of Pendrin in Intercalated Cells Produces Chloride-Sensitive Hypertension

    Science.gov (United States)

    Jacques, Thibaut; Picard, Nicolas; Miller, R. Lance; Riemondy, Kent A.; Houillier, Pascal; Sohet, Fabien; Ramakrishnan, Suresh K.; Büsst, Cara J.; Jayat, Maximilien; Cornière, Nicolas; Hassan, Hatim; Aronson, Peter S.; Hennings, Jean Christopher; Hübner, Christian A.; Nelson, Raoul D.; Chambrey, Régine

    2013-01-01

    Inherited and acquired disorders that enhance the activity of transporters mediating renal tubular Na+ reabsorption are well established causes of hypertension. It is unclear, however, whether primary activation of an Na+-independent chloride transporter in the kidney can also play a pathogenic role in this disease. Here, mice overexpressing the chloride transporter pendrin in intercalated cells of the distal nephron (TgB1-hPDS mice) displayed increased renal absorption of chloride. Compared with normal mice, these transgenic mice exhibited a delayed increase in urinary NaCl and ultimately, developed hypertension when exposed to a high-salt diet. Administering the same sodium intake as NaHCO3 instead of NaCl did not significantly alter BP, indicating that the hypertension in the transgenic mice was chloride-sensitive. Moreover, excessive chloride absorption by pendrin drove parallel absorption of sodium through the epithelial sodium channel ENaC and the sodium-driven chloride/bicarbonate exchanger (Ndcbe), despite an appropriate downregulation of these sodium transporters in response to the expanded vascular volume and hypertension. In summary, chloride transport in the distal nephron can play a primary role in driving NaCl transport in this part of the kidney, and a primary abnormality in renal chloride transport can provoke arterial hypertension. Thus, we conclude that the chloride/bicarbonate exchanger pendrin plays a major role in controlling net NaCl absorption, thereby influencing BP under conditions of high salt intake. PMID:23766534

  17. Overexpression of pendrin in intercalated cells produces chloride-sensitive hypertension.

    Science.gov (United States)

    Jacques, Thibaut; Picard, Nicolas; Miller, R Lance; Riemondy, Kent A; Houillier, Pascal; Sohet, Fabien; Ramakrishnan, Suresh K; Büsst, Cara J; Jayat, Maximilien; Cornière, Nicolas; Hassan, Hatim; Aronson, Peter S; Hennings, Jean Christopher; Hübner, Christian A; Nelson, Raoul D; Chambrey, Régine; Eladari, Dominique

    2013-06-01

    Inherited and acquired disorders that enhance the activity of transporters mediating renal tubular Na(+) reabsorption are well established causes of hypertension. It is unclear, however, whether primary activation of an Na(+)-independent chloride transporter in the kidney can also play a pathogenic role in this disease. Here, mice overexpressing the chloride transporter pendrin in intercalated cells of the distal nephron (Tg(B1-hPDS) mice) displayed increased renal absorption of chloride. Compared with normal mice, these transgenic mice exhibited a delayed increase in urinary NaCl and ultimately, developed hypertension when exposed to a high-salt diet. Administering the same sodium intake as NaHCO3 instead of NaCl did not significantly alter BP, indicating that the hypertension in the transgenic mice was chloride-sensitive. Moreover, excessive chloride absorption by pendrin drove parallel absorption of sodium through the epithelial sodium channel ENaC and the sodium-driven chloride/bicarbonate exchanger (Ndcbe), despite an appropriate downregulation of these sodium transporters in response to the expanded vascular volume and hypertension. In summary, chloride transport in the distal nephron can play a primary role in driving NaCl transport in this part of the kidney, and a primary abnormality in renal chloride transport can provoke arterial hypertension. Thus, we conclude that the chloride/bicarbonate exchanger pendrin plays a major role in controlling net NaCl absorption, thereby influencing BP under conditions of high salt intake.

  18. Green tea polyphenols rescue of brain defects induced by overexpression of DYRK1A.

    Directory of Open Access Journals (Sweden)

    Fayçal Guedj

    Full Text Available Individuals with partial HSA21 trisomies and mice with partial MMU16 trisomies containing an extra copy of the DYRK1A gene present various alterations in brain morphogenesis. They present also learning impairments modeling those encountered in Down syndrome. Previous MRI and histological analyses of a transgenic mice generated using a human YAC construct that contains five genes including DYRK1A reveal that DYRK1A is involved, during development, in the control of brain volume and cell density of specific brain regions. Gene dosage correction induces a rescue of the brain volume alterations. DYRK1A is also involved in the control of synaptic plasticity and memory consolidation. Increased gene dosage results in brain morphogenesis defects, low BDNF levels and mnemonic deficits in these mice. Epigallocatechin gallate (EGCG - a member of a natural polyphenols family, found in great amount in green tea leaves - is a specific and safe DYRK1A inhibitor. We maintained control and transgenic mice overexpressing DYRK1A on two different polyphenol-based diets, from gestation to adulthood. The major features of the transgenic phenotype were rescued in these mice.

  19. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

    OpenAIRE

    Kandadi, Machender R; Yu, Xuejun; Frankel, Arthur E; Ren, Jun

    2012-01-01

    Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT) and cardiac-specific catalase overexpression mice were challenged...

  20. Hepatic overexpression of the prodomain of furin lessens progression of atherosclerosis and reduces vascular remodeling in response to injury.

    Science.gov (United States)

    Lei, Xia; Basu, Debapriya; Li, Zhiqiang; Zhang, Maoxiang; Rudic, R Dan; Jiang, Xian-Cheng; Jin, Weijun

    2014-09-01

    Atherosclerosis is a complex disease, involving elevated LDL-c, lipid accumulation in the blood vessel wall, foam cell formation and vascular dysfunction. Lowering plasma LDL-c is the cornerstone of current management of cardiovascular disease. However, new approaches which reduce plasma LDL-c and lessen the pathological vascular remodeling occurring in the disease should also have therapeutic value. Previously, we found that overexpression of profurin, the 83-amino acid prodomain of the proprotein convertase furin, lowered plasma HDL levels in wild-type mice. The question that remained was whether it had effects on apolipoprotein B (ApoB)-containing lipoproteins. Adenovirus mediated overexpression of hepatic profurin in Ldlr(-/-)mice and wild-type mice were used to evaluate effects of profurin on ApoB-containing lipoproteins, atherosclerosis and vascular remodeling. Hepatic profurin overexpression resulted in a significant reduction in atherosclerotic lesion development in Ldlr(-/-)mice and a robust reduction in plasma LDL-c. Metabolic studies revealed lower secretion of ApoB and triglycerides in VLDL particles. Mechanistic studies showed that in the presence of profurin, hepatic ApoB, mainly ApoB100, was degraded by proteasomes. There was no effect on ApoB mRNA expression. Importantly, short-term hepatic profurin overexpression did not result in hepatic lipid accumulation. Blood vessel wall thickening caused by either wire-induced femoral artery injury or common carotid artery ligation was reduced. Profurin expression inhibited proliferation and migration in vascular smooth muscle cells in vitro. These results indicate that a profurin-based therapy has the potential to treat atherosclerosis by improving metabolic lipid profiles and reducing both atherosclerotic lesion development and pathological vascular remodeling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Increased atherosclerosis in mice with increased vascular biglycan content.

    Science.gov (United States)

    Thompson, Joel C; Tang, Tao; Wilson, Patricia G; Yoder, Meghan H; Tannock, Lisa R

    2014-07-01

    The response to retention hypothesis of atherogenesis proposes that atherosclerosis is initiated via the retention of atherogenic lipoproteins by vascular proteoglycans. Co-localization studies suggest that of all the vascular proteoglycans, biglycan is the one most closely co-localized with LDL. The goal of this study was to determine if over-expression of biglycan in hyperlipidemic mice would increase atherosclerosis development. Transgenic mice were developed by expressing biglycan under control of the smooth muscle actin promoter, and were crossed to the LDL receptor deficient (C57BL/6 background) atherosclerotic mouse model. Biglycan transgenic and non-transgenic control mice were fed an atherogenic Western diet for 4-12 weeks. LDL receptor deficient mice overexpressing biglycan under control of the smooth muscle alpha actin promoter had increased atherosclerosis development that correlated with vascular biglycan content. Increased vascular biglycan content predisposes to increased lipid retention and increased atherosclerosis development. Published by Elsevier Ireland Ltd.

  2. Overexpressed TP73 induces apoptosis in medulloblastoma

    International Nuclear Information System (INIS)

    Castellino, Robert C; De Bortoli, Massimiliano; Lin, Linda L; Skapura, Darlene G; Rajan, Jessen A; Adesina, Adekunle M; Perlaky, Laszlo; Irwin, Meredith S; Kim, John YH

    2007-01-01

    Medulloblastoma is the most common malignant brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated ΔNp73 to assess their effects on growth. We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the ΔNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and ΔNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and ΔNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods. Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated ΔNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or ΔNp73 induced apoptosis under basal growth conditions in vitro and sensitized them to cell death in response to

  3. Overexpressed TP73 induces apoptosis in medulloblastoma

    Directory of Open Access Journals (Sweden)

    Perlaky Laszlo

    2007-07-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated ΔNp73 to assess their effects on growth. Methods We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the ΔNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and ΔNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and ΔNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods. Results Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated ΔNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or ΔNp73 induced apoptosis under basal growth conditions in vitro and

  4. Cardiac-specific overexpression of catalase prevents diabetes-induced pathological changes by inhibiting NF-κB signaling activation in the heart.

    Science.gov (United States)

    Cong, Weitao; Ruan, Dandan; Xuan, Yuanhu; Niu, Chao; Tao, Youli; Wang, Yang; Zhan, Kungao; Cai, Lu; Jin, Litai; Tan, Yi

    2015-12-01

    Catalase is an antioxidant enzyme that specifically catabolizes hydrogen peroxide (H2O2). Overexpression of catalase via a heart-specific promoter (CAT-TG) was reported to reduce diabetes-induced accumulation of reactive oxygen species (ROS) and further prevent diabetes-induced pathological abnormalities, including cardiac structural derangement and left ventricular abnormity in mice. However, the mechanism by which catalase overexpression protects heart function remains unclear. This study found that activation of a ROS-dependent NF-κB signaling pathway was downregulated in hearts of diabetic mice overexpressing catalase. In addition, catalase overexpression inhibited the significant increase in nitration levels of key enzymes involved in energy metabolism, including α-oxoglutarate dehydrogenase E1 component (α-KGD) and ATP synthase α and β subunits (ATP-α and ATP-β). To assess the effects of the NF-κB pathway activation on heart function, Bay11-7082, an inhibitor of the NF-κB signaling pathway, was injected into diabetic mice, protecting mice against the development of cardiac damage and increased nitrative modifications of key enzymes involved in energy metabolism. In conclusion, these findings demonstrated that catalase protects mouse hearts against diabetic cardiomyopathy, partially by suppressing NF-κB-dependent inflammatory responses and associated protein nitration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. AAV-mediated Sirt1 overexpression in skeletal muscle activates oxidative capacity but does not prevent insulin resistance

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    Laia Vil

    2016-01-01

    Full Text Available Type 2 diabetes is characterized by triglyceride accumulation and reduced lipid oxidation capacity in skeletal muscle. SIRT1 is a key protein in the regulation of lipid oxidation and its expression is reduced in the skeletal muscle of insulin resistant mice. In this tissue, Sirt1 up-regulates the expression of genes involved in oxidative metabolism and improves mitochondrial function mainly through PPARGC1 deacetylation. Here we examined whether Sirt1 overexpression mediated by adeno-associated viral vectors of serotype 1 (AAV1 specifically in skeletal muscle can counteract the development of insulin resistance induced by a high fat diet in mice. AAV1-Sirt1-treated mice showed up-regulated expression of key genes related to β-oxidation together with increased levels of phosphorylated AMP protein kinase. Moreover, SIRT1 overexpression in skeletal muscle also increased basal phosphorylated levels of AKT. However, AAV1-Sirt1 treatment was not enough to prevent high fat diet-induced obesity and insulin resistance. Although Sirt1 gene transfer to skeletal muscle induced changes at the muscular level related with lipid and glucose homeostasis, our data indicate that overexpression of SIRT1 in skeletal muscle is not enough to improve whole-body insulin resistance and that suggests that SIRT1 has to be increased in other metabolic tissues to prevent insulin resistance.

  6. Postnatally disturbed pancreatic islet cell distribution in human islet amyloid polypeptide transgenic mice

    NARCIS (Netherlands)

    Wong, HY; Ahren, B; Lips, CJM; Hoppener, JWM; Sundler, F

    2003-01-01

    Objective: Islet amyloid polypeptide (IAPP)/amylin is produced by the pancreatic islet beta-cells, which also produce insulin. To study potential functions of IAPP, we have generated transgenic mice overexpressing human IAPP (hIAPP) in the beta-cells. These mice show a diabetic phenotype when

  7. Fibroblast growth factor 21 has no direct role in regulating fertility in female mice

    Directory of Open Access Journals (Sweden)

    Garima Singhal

    2016-08-01

    Conclusions: We conclude that FGF21 is not a direct physiological regulator of fertility in mice. The infertility observed in FGF21 overexpressing mice is likely driven by the increased energy expenditure and consequent excess calorie requirements resulting from high FGF21 levels.

  8. Cyclooxygenase-2 is overexpressed in chronic pancreatitis.

    Science.gov (United States)

    Schlosser, Wolfgang; Schlosser, Sophia; Ramadani, Marco; Gansauge, Frank; Gansauge, Susanne; Beger, Hans-Günter

    2002-07-01

    Cyclooxygenase enzymes catalyze a critical step in the conversion of arachidonic acid to prostaglandins, which are important mediators of acute and chronic inflammation. The constitutively expressed cyclooxygenase-1 (COX-1) appears to regulate many normal physiologic functions in several cell types, whereas the inducible cyclooxygenase-2 (COX-2) enzyme mediates the inflammatory response. We investigated the expression of COX-2 in tissues of 35 patients with chronic pancreatitis, 6 patients with pancreatic cancer, and 5 control patients by immunohistochemical analysis and correlations to clinicopathologic features. We found an overexpression of COX-2 in the atrophic acinar cells (80% of patients), hyperplastic ductal cells (86% of patients), and islets cells (97% of patients) but not in normal pancreatic tissues. The COX-2 overexpression in the tissue of patients with chronic pancreatitis was significantly correlated with the frequency of acute attacks of pancreatitis. Tissue from patients who had more than five acute attacks of pancreatitis (n = 10) exhibited COX-2 immunoreactivity of a significantly higher score in atrophic acinar cells (p = 0.004). No correlation could be found with other examined clinical features such as duration of the disease, diabetes, alcohol consumption, smoking, or pain. Our results support the hypothesis that COX-2 may be involved in inflammatory responses in chronic pancreatitis and in the progression of this chronic inflammatory disease.

  9. Nucleophosmin is overexpressed in thyroid tumors

    Energy Technology Data Exchange (ETDEWEB)

    Pianta, Annalisa; Puppin, Cinzia [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Franzoni, Alessandra; Fabbro, Dora [Azienda Ospedaliero-Universitaria ' S. Maria della Misericordia' Udine, Udine (Italy); Di Loreto, Carla [Dipartimento di Ricerche Mediche e Morfologiche, Universita di Udine, Udine (Italy); Bulotta, Stefania [Department of Pharmacobiological Sciences, Universita di Catanzaro ' Magna Graecia' , Catanzaro (Italy); Deganuto, Marta; Paron, Igor; Tell, Gianluca [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Puxeddu, Efisio [Department of Internal Medicine, Universita di Perugia, Perugia (Italy); Filetti, Sebastiano [Department of Clinical Sciences, Universita di Roma ' La Sapienza' , Roma (Italy); Russo, Diego [Department of Pharmacobiological Sciences, Universita di Catanzaro ' Magna Graecia' , Catanzaro (Italy); Damante, Giuseppe, E-mail: giuseppe.damante@uniud.it [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Azienda Ospedaliero-Universitaria ' S. Maria della Misericordia' Udine, Udine (Italy)

    2010-07-02

    Nucleophosmin (NPM) is a protein that contributes to several cell functions. Depending on the context, it can act as an oncogene or tumor suppressor. No data are available on NPM expression in thyroid cells. In this work, we analyzed both NPM mRNA and protein levels in a series of human thyroid tumor tissues and cell lines. By using immunohistochemistry, NPM overexpression was detected in papillary, follicular, undifferentiated thyroid cancer, and also in follicular benign adenomas, indicating it as an early event during thyroid tumorigenesis. In contrast, various levels of NPM mRNA levels as detected by quantitative RT-PCR were observed in tumor tissues, suggesting a dissociation between protein and transcript expression. The same behavior was observed in the normal thyroid FRTL5 cell lines. In these cells, a positive correlation between NPM protein levels, but not mRNA, and proliferation state was detected. By using thyroid tumor cell lines, we demonstrated that such a post-mRNA regulation may depend on NPM binding to p-Akt, whose levels were found to be increased in the tumor cells, in parallel with reduction of PTEN. In conclusion, our present data demonstrate for the first time that nucleophosmin is overexpressed in thyroid tumors, as an early event of thyroid tumorigenesis. It seems as a result of a dysregulation occurring at protein and not transcriptional level related to an increase of p-Akt levels of transformed thyrocytes.

  10. Transgenic overexpression of NanogP8 in the mouse prostate is insufficient to initiate tumorigenesis but weakly promotes tumor development in the Hi-Myc mouse model.

    Science.gov (United States)

    Liu, Bigang; Gong, Shuai; Li, Qiuhui; Chen, Xin; Moore, John; Suraneni, Mahipal V; Badeaux, Mark D; Jeter, Collene R; Shen, Jianjun; Mehmood, Rashid; Fan, Qingxia; Tang, Dean G

    2017-08-08

    This project was undertaken to address a critical cancer biology question: Is overexpression of the pluripotency molecule Nanog sufficient to initiate tumor development in a somatic tissue? Nanog1 is critical for the self-renewal and pluripotency of ES cells, and its retrotransposed homolog, NanogP8 is preferentially expressed in somatic cancer cells. Our work has shown that shRNA-mediated knockdown of NanogP8 in prostate, breast, and colon cancer cells inhibits tumor regeneration whereas inducible overexpression of NanogP8 promotes cancer stem cell phenotypes and properties. To address the key unanswered question whether tissue-specific overexpression of NanogP8 is sufficient to promote tumor development in vivo , we generated a NanogP8 transgenic mouse model, in which the ARR 2 PB promoter was used to drive NanogP8 cDNA. Surprisingly, the ARR 2 PB-NanogP8 transgenic mice were viable, developed normally, and did not form spontaneous tumors in >2 years. Also, both wild type and ARR 2 PB-NanogP8 transgenic mice responded similarly to castration and regeneration and castrated ARR 2 PB-NanogP8 transgenic mice also did not develop tumors. By crossing the ARR 2 PB-NanogP8 transgenic mice with ARR 2 PB-Myc (i.e., Hi-Myc) mice, we found that the double transgenic (i.e., ARR 2 PB-NanogP8; Hi-Myc) mice showed similar tumor incidence and histology to the Hi-Myc mice. Interestingly, however, we observed white dots in the ventral lobes of the double transgenic prostates, which were characterized as overgrown ductules/buds featured by crowded atypical Nanog-expressing luminal cells. Taken together, our present work demonstrates that transgenic overexpression of NanogP8 in the mouse prostate is insufficient to initiate tumorigenesis but weakly promotes tumor development in the Hi-Myc mouse model.

  11. Fractalkine overexpression suppresses tau pathology in a mouse model of tauopathy.

    Science.gov (United States)

    Nash, Kevin R; Lee, Daniel C; Hunt, Jerry B; Morganti, Josh M; Selenica, Maj-Linda; Moran, Peter; Reid, Patrick; Brownlow, Milene; Guang-Yu Yang, Clement; Savalia, Miloni; Gemma, Carmelina; Bickford, Paula C; Gordon, Marcia N; Morgan, David

    2013-06-01

    Alzheimer's disease is characterized by amyloid plaques, neurofibrillary tangles, glial activation, and neurodegeneration. In mouse models, inflammatory activation of microglia accelerates tau pathology. The chemokine fractalkine serves as an endogenous neuronal modulator to quell microglial activation. Experiments with fractalkine receptor null mice suggest that fractalkine signaling diminishes tau pathology, but exacerbates amyloid pathology. Consistent with this outcome, we report here that soluble fractalkine overexpression using adeno-associated viral vectors significantly reduced tau pathology in the rTg4510 mouse model of tau deposition. Furthermore, this treatment reduced microglial activation and appeared to prevent neurodegeneration normally found in this model. However, in contrast to studies with fractalkine receptor null mice, parallel studies in an APP/PS1 model found no effect of increased fractalkine signaling on amyloid deposition. These data argue that agonism at fractalkine receptors might be an excellent target for therapeutic intervention in tauopathies, including those associated with amyloid deposition. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Transgenic overexpression of LARGE induces α-dystroglycan hyperglycosylation in skeletal and cardiac muscle.

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    Martin Brockington

    2010-12-01

    Full Text Available LARGE is one of seven putative or demonstrated glycosyltransferase enzymes defective in a common group of muscular dystrophies with reduced glycosylation of α-dystroglycan. Overexpression of LARGE induces hyperglycosylation of α-dystroglycan in both wild type and in cells from dystroglycanopathy patients, irrespective of their primary gene defect, restoring functional glycosylation. Viral delivery of LARGE to skeletal muscle in animal models of dystroglycanopathy has identical effects in vivo, suggesting that the restoration of functional glycosylation could have therapeutic applications in these disorders. Pharmacological strategies to upregulate Large expression are also being explored.In order to asses the safety and efficacy of long term LARGE over-expression in vivo, we have generated four mouse lines expressing a human LARGE transgene. On observation, LARGE transgenic mice were indistinguishable from the wild type littermates. Tissue analysis from young mice of all four lines showed a variable pattern of transgene expression: highest in skeletal and cardiac muscles, and lower in brain, kidney and liver. Transgene expression in striated muscles correlated with α-dystroglycan hyperglycosylation, as determined by immunoreactivity to antibody IIH6 and increased laminin binding on an overlay assay. Other components of the dystroglycan complex and extracellular matrix ligands were normally expressed, and general muscle histology was indistinguishable from wild type controls. Further detailed muscle physiological analysis demonstrated a loss of force in response to eccentric exercise in the older, but not in the younger mice, suggesting this deficit developed over time. However this remained a subclinical feature as no pathology was observed in older mice in any muscles including the diaphragm, which is sensitive to mechanical load-induced damage.This work shows that potential therapies in the dystroglycanopathies based on LARGE upregulation

  13. Functional Overexpression of Vomeronasal Receptors Using a Herpes Simplex Virus Type 1 (HSV-1-Derived Amplicon.

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    Benjamin Stein

    Full Text Available In mice, social behaviors such as mating and aggression are mediated by pheromones and related chemosignals. The vomeronasal organ (VNO detects olfactory information from other individuals by sensory neurons tuned to respond to specific chemical cues. Receptors expressed by vomeronasal neurons are implicated in selective detection of these cues. Nearly 400 receptor genes have been identified in the mouse VNO, but the tuning properties of individual receptors remain poorly understood, in part due to the lack of a robust heterologous expression system. Here we develop a herpes virus-based amplicon delivery system to overexpress three types of vomeronasal receptor genes and to characterize cell responses to their proposed ligands. Through Ca2+ imaging in native VNO cells we show that virus-induced overexpression of V1rj2, V2r1b or Fpr3 caused a pronounced increase of responsivity to sulfated steroids, MHC-binding peptide or the synthetic hexapeptide W-peptide, respectively. Other related ligands were not recognized by infected individual neurons, indicating a high degree of selectivity by the overexpressed receptor. Removal of G-protein signaling eliminates Ca2+ responses, indicating that the endogenous second messenger system is essential for observing receptor activation. Our results provide a novel expression system for vomeronasal receptors that should be useful for understanding the molecular logic of VNO ligand detection. Functional expression of vomeronasal receptors and their deorphanization provides an essential requirement for deciphering the neural mechanisms controlling behavior.

  14. Cardiac‐specific Hexokinase 2 Overexpression Attenuates Hypertrophy by Increasing Pentose Phosphate Pathway Flux

    Science.gov (United States)

    McCommis, Kyle S.; Douglas, Diana L.; Krenz, Maike; Baines, Christopher P.

    2013-01-01

    Background The enzyme hexokinase‐2 (HK2) phosphorylates glucose, which is the initiating step in virtually all glucose utilization pathways. Cardiac hypertrophy is associated with a switch towards increased glucose metabolism and decreased fatty acid metabolism. Recent evidence suggests that the increased glucose utilization is compensatory to the down‐regulated fatty acid metabolism during hypertrophy and is, in fact, beneficial. Therefore, we hypothesized that increasing glucose utilization by HK2 overexpression would decrease cardiac hypertrophy. Methods and Results Mice with cardiac‐specific HK2 overexpression displayed decreased hypertrophy in response to isoproterenol. Neonatal rat ventricular myocytes (NRVMs) infected with an HK2 adenovirus similarly displayed decreased hypertrophy in response to phenylephrine. Hypertrophy increased reactive oxygen species (ROS) levels, which were attenuated by HK2 overexpression, thereby decreasing NRVM hypertrophy and death. HK2 appears to modulate ROS via the pentose phosphate pathway, as inhibition of glucose‐6‐phosphate dehydrogenase with dehydroepiandrosterone decreased the ability of HK2 to diminish ROS and hypertrophy. Conclusions These results suggest that HK2 attenuates cardiac hypertrophy by decreasing ROS accumulation via increased pentose phosphate pathway flux. PMID:24190878

  15. Overexpression of IGF-I receptor in HeLa cells enhances in vivo radioresponse

    International Nuclear Information System (INIS)

    Kaneko, Haruna; Yu, Dong; Miura, Masahiko

    2007-01-01

    Insulin-like growth factor I receptor (IGF-IR) is a transmembrane receptor tyrosine kinase whose activation strongly promotes cell growth and survival. We previously reported that IGF-IR activity confers intrinsic radioresistance in mouse embryo fibroblasts in vitro. However, it is still unclear whether tumor cells overexpressing IGF-IR exhibit radioresistance in vivo. For this purpose, we established HeLa cells that overexpress IGF-IR (HeLa-R), subcutaneously transplanted these cells into nude mice, and examined radioresponse in the resulting solid tumors. HeLa-R cells exhibited typical in vitro phenotypes generally observed in IGF-IR-overexpressing cells, as well as significant intrinsic radioresistance in vitro compared with parent cells. As expected, the transplanted HeLa-R tumors grew at a remarkably higher rate than parent tumors. Histological analysis revealed that HeLa-R tumors expressed more VEGF and had a higher density of tumor vessels. Unexpectedly, a marked growth delay was observed in HeLa-R tumors following 10 Gy of X-irradiation. Immunostaining of HeLa-R tumors for the hypoxia marker pimonidazole revealed a significantly lower level of hypoxic cells. Moreover, clamp hypoxia significantly increased radioresistance in HeLa-R tumors. Tumor microenvironments in vivo generated by the IGF-IR expression thus could be a major factor in determining the tumor radioresponse in vivo

  16. Overexpression of the mitochondrial T3 receptor p43 induces a shift in skeletal muscle fiber types.

    Directory of Open Access Journals (Sweden)

    François Casas

    Full Text Available In previous studies, we have characterized a new hormonal pathway involving a mitochondrial T3 receptor (p43 acting as a mitochondrial transcription factor and consequently stimulating mitochondrial activity and mitochondrial biogenesis. We have established the involvement of this T3 pathway in the regulation of in vitro myoblast differentiation. We have generated mice overexpressing p43 under control of the human alpha-skeletal actin promoter. In agreement with the previous characterization of this promoter, northern-blot and western-blot experiments confirmed that after birth p43 was specifically overexpressed in skeletal muscle. As expected from in vitro studies, in 2-month old mice, p43 overexpression increased mitochondrial genes expression and mitochondrial biogenesis as attested by the increase of mitochondrial mass and mt-DNA copy number. In addition, transgenic mice had a body temperature 0.8 degrees C higher than control ones and displayed lower plasma triiodothyronine levels. Skeletal muscles of transgenic mice were redder than wild-type animals suggesting an increased oxidative metabolism. In line with this observation, in gastrocnemius, we recorded a strong increase in cytochrome oxidase activity and in mitochondrial respiration. Moreover, we observed that p43 drives the formation of oxidative fibers: in soleus muscle, where MyHC IIa fibers were partly replaced by type I fibers; in gastrocnemius muscle, we found an increase in MyHC IIa and IIx expression associated with a reduction in the number of glycolytic fibers type IIb. In addition, we found that PGC-1alpha and PPARdelta, two major regulators of muscle phenotype were up regulated in p43 transgenic mice suggesting that these proteins could be downstream targets of mitochondrial activity. These data indicate that the direct mitochondrial T3 pathway is deeply involved in the acquisition of contractile and metabolic features of muscle fibers in particular by regulating PGC-1alpha

  17. Overexpression of IL-7R alpha provides a competitive advantage during early T-cell development.

    Science.gov (United States)

    Laouar, Yasmina; Crispe, I Nicholas; Flavell, Richard A

    2004-03-15

    Critical checkpoints controlling early thymic T-cell development and homeostasis are set by the proper signaling function of the interleukin 7 receptor (IL-7R) and the pre-T-cell antigen receptor. Although alpha beta T-cell development is observed in IL-7- and IL-7R alpha-deficient mice, the number of thymocytes is significantly reduced, implying a role for the IL-7R in controlling the size of the thymic T-cell compartment. Here, we report the overexpression of IL-7R alpha that occurs in the early T-cell compartment from AKR/J mice, animals that are highly susceptible to the spontaneous development of thymoma. Increased IL-7R alpha was revealed by surface staining, and increased IL-7R alpha mRNA was documented by using reverse transcriptase-polymerase chain reaction (RT-PCR). This resulted in increased survival of AKR/J early thymocytes, shown by the decreased frequency of TUNEL(+) (terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate [dUTP]-fluorescein nick end labeling) cells. In an in vivo thymocyte repopulation model, AKR/J thymocytes had a selective advantage over healthy thymocytes. This advantage occurred at early stages of T-cell development. Our findings support the model that overexpression of growth factor receptors can contribute to proliferation and malignancy.

  18. Restriction landmark genomic scanning of mouse liver tumors for gene amplification: overexpression of cyclin A2.

    Science.gov (United States)

    Haddad, R; Morrow, A D; Plass, C; Held, W A

    2000-07-21

    SV40 T/t antigen-induced liver tumors from transgenic mice were analyzed by Restriction Landmark Genomic Scanning (RLGS). Using NotI as the restriction landmark, RLGS targets CpG islands found in gene-rich regions of the genome. Since many RLGS landmarks are mapped, the candidate gene approach can be used to help determine which genes are altered in tumors. RLGS analysis revealed one tumor-specific amplification mapping close to CcnA2 (cyclin A2) and Fgf2 (fibroblast growth factor 2). Southern analysis confirmed that both oncogenes are amplified in this tumor and in a second, independent liver tumor. Whereas Fgf2 RNA is undetectable in tumors, CcnA2 RNA and cyclin A2 protein was overexpressed in 25 and 50% of tumors, respectively. Combining RLGS with the candidate gene approach indicates that cyclin A2 amplification and overexpression is a likely selected event in transgenic mouse liver tumors. Our results also indicate that our mouse model for liver tumorigenesis in mice accurately recapitulates events observed in human hepatocellular carcinoma. Copyright 2000 Academic Press.

  19. Selective over-expression of endothelin-1 in endothelial cells exacerbates inner retinal edema and neuronal death in ischemic retina.

    Directory of Open Access Journals (Sweden)

    Simon S F Cheung

    Full Text Available The level of endothelin-1 (ET-1, a potent vasoconstrictor, was associated with retinopathy under ischemia. The effects of endothelial endothelin-1 (ET-1 over-expression in a transgenic mouse model using Tie-1 promoter (TET-1 mice on pathophysiological changes of retinal ischemia were investigated by intraluminal insertion of a microfilament up to middle cerebral artery (MCA to transiently block the ophthalmic artery. Two-hour occlusion and twenty-two-hour reperfusion were performed in homozygous (Hm TET-1 mice and their non-transgenic (NTg littermates. Presence of pyknotic nuclei in ganglion cell layer (GCL was investigated in paraffin sections of ipsilateral (ischemic and contralateral (non-ischemic retinae, followed by measurement of the thickness of inner retinal layer. Moreover, immunocytochemistry of glial fibrillary acidic protein (GFAP, glutamine synthetase (GS and aquaporin-4 (AQP4 peptides on retinal sections were performed to study glial cell reactivity, glutamate metabolism and water accumulation, respectively after retinal ischemia. Similar morphology was observed in the contralateral retinae of NTg and Hm TET-1 mice, whereas ipsilateral retina of NTg mice showed slight structural and cellular changes compared with the corresponding contralateral retina. Ipsilateral retinae of Hm TET-1 mice showed more significant changes when compared with ipsilateral retina of NTg mice, including more prominent cell death in GCL characterized by the presence of pyknotic nuclei, elevated GS immunoreactivity in Müller cell bodies and processes, increased AQP-4 immunoreactivity in Müller cell processes, and increased inner retinal thickness. Thus, over-expression of endothelial ET-1 in TET-1 mice may contribute to increased glutamate-induced neurotoxicity on neuronal cells and water accumulation in inner retina leading to edema.

  20. GSK-3β Overexpression Alters the Dendritic Spines of Developmentally Generated Granule Neurons in the Mouse Hippocampal Dentate Gyrus

    Science.gov (United States)

    Pallas-Bazarra, Noemí; Kastanauskaite, Asta; Avila, Jesús; DeFelipe, Javier; Llorens-Martín, María

    2017-01-01

    The dentate gyrus (DG) plays a crucial role in hippocampal-related memory. The most abundant cellular type in the DG, namely granule neurons, are developmentally generated around postnatal day P6 in mice. Moreover, a unique feature of the DG is the occurrence of adult hippocampal neurogenesis, a process that gives rise to newborn granule neurons throughout life. Adult-born and developmentally generated granule neurons share some maturational aspects but differ in others, such as in their positioning within the granule cell layer. Adult hippocampal neurogenesis encompasses a series of plastic changes that modify the function of the hippocampal trisynaptic network. In this regard, it is known that glycogen synthase kinase 3β (GSK-3β) regulates both synaptic plasticity and memory. By using a transgenic mouse overexpressing GSK-3β in hippocampal neurons, we previously demonstrated that the overexpression of this kinase has deleterious effects on the maturation of newborn granule neurons. In the present study, we addressed the effects of GSK-3β overexpression on the morphology and number of dendritic spines of developmentally generated granule neurons. To this end, we performed intracellular injections of Lucifer Yellow in developmentally generated granule neurons of wild-type and GSK-3β-overexpressing mice and analyzed the number and morphologies of dendritic spines (namely, stubby, thin and mushroom). GSK-3β overexpression led to a general reduction in the number of dendritic spines. In addition, it caused a slight reduction in the percentage, head diameter and length of thin spines, whereas the head diameter of mushroom spines was increased. PMID:28344548

  1. Recombinant adenovirus-mediated overexpression of PTEN and KRT10 improves cisplatin resistance of ovarian cancer in vitro and in vivo.

    Science.gov (United States)

    Wu, H; Wang, K; Liu, W; Hao, Q

    2015-06-18

    Drug resistance is a major cause of treatment failure in ovarian cancer patients, and novel therapeutic strategies are urgently needed. Overexpression of phosphatase and tensin homolog (PTEN) has been shown to preserve the cisplatin-resistance of ovarian cancer cells, while cisplatin-induced keratin 10 (KRT10) overexpression mediates the resistance-reversing effect of PTEN. However, whether overexpression of PTEN or KRT10 can improve the cisplatin resistance of ovarian cancer in vivo has not been investigated. Therefore, we investigated the effects of adenovirus-mediated PTEN or KRT10 overexpression on the cisplatin resistance of ovarian cancer in vivo. Recombinant adenoviruses carrying the gene for PTEN or KRT10 were constructed. The effects of overexpression of PTEN and KRT10 on cisplatin resistance of ovarian cancer cells were examined using the 3(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) and TdT-mediated dUTP nick-end labeling (TUNEL) assays in vitro. Subcutaneously transplanted nude mice, as a model of human ovarian cancer, were used to test the effects of PTEN and KRT10 on cisplatin resistance of ovarian cancer in vivo. The MTT assay showed that recombinant adenovirus-mediated overexpression of KRT10 and PTEN enhanced the proliferation inhibition effect of cisplatin on C13K cells. Recombinant adenovirus-mediated overexpression of KRT10 and PTEN also increased the cisplatin-induced apoptosis rate of C13K cells. Furthermore, recombinant adenovirus-mediated overexpression of KRT10 and PTEN enhanced the inhibitory effect of cisplatin on C13K xenograft tumor growth. Thus, recombinant adenovirus-mediated overexpression of KRT10 and PTEN may improve the cisplatin resistance of ovarian cancer in vitro and in vivo.

  2. Smooth Muscle Specific Overexpression of p22phox Potentiates Carotid Artery Wall Thickening in Response to Injury

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    Michael R. Manogue

    2015-01-01

    Full Text Available We hypothesized that transgenic mice overexpressing the p22phox subunit of the NADPH oxidase selectively in smooth muscle (Tgp22smc would exhibit an exacerbated response to transluminal carotid injury compared to wild-type mice. To examine the role of reactive oxygen species (ROS as a mediator of vascular injury, the injury response was quantified by measuring wall thickness (WT and cross-sectional wall area (CSWA of the injured and noninjured arteries in both Tgp22smc and wild-type animals at days 3, 7, and 14 after injury. Akt, p38 MAPK, and Src activation were evaluated at the same time points using Western blotting. WT and CSWA following injury were significantly greater in Tgp22smc mice at both 7 and 14 days after injury while noninjured contralateral carotids were similar between groups. Apocynin treatment attenuated the injury response in both groups and rendered the response similar between Tgp22smc mice and wild-type mice. Following injury, carotid arteries from Tgp22smc mice demonstrated elevated activation of Akt at day 3, while p38 MAPK and Src activation was elevated at day 7 compared to wild-type mice. Both increased activation and temporal regulation of these signaling pathways may contribute to enhanced vascular growth in response to injury in this transgenic model of elevated vascular ROS.

  3. IL-10 Overexpression Alters Survival in the Setting of Gram Negative Pneumonia Following Lung Contusion

    Science.gov (United States)

    Dolgachev, Vladislav A.; Yu, Bi; Sun, Lei; Shanley, Thomas P.; Raghavendran, Krishnan; Hemmila, Mark R.

    2014-01-01

    Objective Lung contusion injury produces a vulnerable window within the inflammatory defenses of the lung that predisposes the patient to pneumonia. IL-10 is a known anti-inflammatory mediator produced by macrophages and capable of down-regulating acute lung inflammation. We investigated the impact of increased levels of IL-10 within the lung on survival and the host response to trauma in the setting of lung contusion and Gram-negative pneumonia. Design A bi-transgenic, tetracycline inducible, lung specific human IL-10 overexpression (IL-10 OE) mouse model and single transgenic (TG-) control mice were used. Mice underwent lung contusion injury (LC) or sham injury (Sham) at time -6 hrs. At time 0 animals were inoculated intratracheally with 500 CFU of Klebsiella pneumoniae (Pneu). Bronchoalveolar lavage fluid (BAL), lung tissue specimens, or purified macrophages were collected. Lung tissue and blood bacteria levels were quantified. Cytokine levels were assayed by ELISA and gene expression levels were evaluated by real time PCR. Cell type identification and quantification was done using real time PCR and flow cytometry. Main Results IL-10 OE mice demonstrated decreased 5 day survival compared to TG-mice following LC+Pneu (0 vs. 30%, pPneu animals (p<0.05). Conclusions Lung specific IL-10 over expression induces alternative activation of alveolar macrophages. This shift in macrophage phenotype decreases intracellular bacterial killing, resulting in a more pronounced bacteremia and accelerated mortality in a model of lung contusion and pneumonia. PMID:24430542

  4. Inhibitory effect of TCCE on CCl4-induced overexpression of IL-6 in acute liver injury.

    Science.gov (United States)

    Gao, Jing; Dou, Huan; Tang, Xin-Hui; Xu, Li-Zhi; Fan, Yi-Mei; Zhao, Xiao-Ning

    2004-11-01

    Terminalia catappa L. leaves have been shown to protect against acute liver injury produced by some hepatotoxicants, but the active components and mechanisms are not clear. This study was designed to characterize the protective effects of the chloroform fraction of the ethanol extract of T. catappa leaves (TCCE) against carbon tetrachloride (CCl4)-induced hepatotoxicity in mice, and analyze the changes in expression level of interleukin-6 (IL-6) in the process. It was found that TCCE pretreatment (10 or 30 mg/kg, ig) protected mice from CCl4 toxicity, as evidenced by the reversed alterations in serum alanine aminotransferase (sALT) and serum aspartate aminotransferase (sAST) activities. Additionally liver tissues were subjected to RT-PCR, Western blot and immunohistochemistry to analyze changes in IL-6 expression. It was found that TCCE markedly suppressed the CCl4-induced over-transcription of IL-6 gene. Consistent with the result, the expression of IL-6 protein was also blocked by TCCE in CCl4-stimulated mice, especially in the area around central vein on liver tissue section. In conclusion, TCCE is effective in protecting mice from the hepatotoxicity produced by CCl4, and the mechanisms underlying its protective effects may be related to the inhibition on the overexpression of IL-6 mainly around terminal hepatic vein.

  5. Overexpression of Catalase in Vascular Smooth Muscle Cells Prevents the Formation of Abdominal Aortic Aneurysms

    Science.gov (United States)

    Parastatidis, Ioannis; Weiss, Daiana; Joseph, Giji; Taylor, W Robert

    2013-01-01

    Objective Elevated levels of oxidative stress have been reported in abdominal aortic aneurysms (AAA), but which reactive oxygen species (ROS) promotes the development of AAA remains unclear. Here we investigate the effect of the hydrogen peroxide (H2O2) degrading enzyme catalase on the formation of AAA. Approach and Results AAA were induced with the application of calcium chloride (CaCl2) on mouse infrarenal aortas. The administration of PEG-catalase, but not saline, attenuated the loss of tunica media and protected against AAA formation (0.91±0.1 mm vs. 0.76±0.09 mm). Similarly, in a transgenic mouse model, catalase over-expression in the vascular smooth muscle cells (VSMC) preserved the thickness of tunica media and inhibited aortic dilatation by 50% (0.85±0.14 mm vs. 0.57±0.08 mm). Further studies showed that injury with CaCl2 decreased catalase expression and activity in the aortic wall. Pharmacologic administration or genetic over-expression of catalase restored catalase activity and subsequently decreased matrix metalloproteinase activity. In addition, a profound reduction in inflammatory markers and VSMC apoptosis was evident in aortas of catalase over-expressing mice. Interestingly, as opposed to infusion of PEG-catalase, chronic over-expression of catalase in VSMC did not alter the total aortic H2O2 levels. Conclusions The data suggest that a reduction in aortic wall catalase activity can predispose to AAA formation. Restoration of catalase activity in the vascular wall enhances aortic VSMC survival and prevents AAA formation primarily through modulation of matrix metalloproteinase activity. PMID:23950141

  6. Lysyl oxidase overexpression accelerates cardiac remodeling and aggravates angiotensin II-induced hypertrophy.

    Science.gov (United States)

    Galán, María; Varona, Saray; Guadall, Anna; Orriols, Mar; Navas, Miquel; Aguiló, Silvia; de Diego, Alicia; Navarro, María A; García-Dorado, David; Rodríguez-Sinovas, Antonio; Martínez-González, José; Rodriguez, Cristina

    2017-09-01

    Lysyl oxidase (LOX) controls matrix remodeling, a key process that underlies cardiovascular diseases and heart failure; however, a lack of suitable animal models has limited our knowledge with regard to the contribution of LOX to cardiac dysfunction. Here, we assessed the impact of LOX overexpression on ventricular function and cardiac hypertrophy in a transgenic LOX (TgLOX) mouse model with a strong cardiac expression of human LOX. TgLOX mice exhibited high expression of the transgene in cardiomyocytes and cardiofibroblasts, which are associated with enhanced LOX activity and H 2 O 2 production and with cardiofibroblast reprogramming. LOX overexpression promoted an age-associated concentric remodeling of the left ventricle and impaired diastolic function. Furthermore, LOX transgenesis aggravated angiotensin II (Ang II)-induced cardiac hypertrophy and dysfunction, which triggered a greater fibrotic response that was characterized by stronger collagen deposition and cross-linking and high expression of fibrotic markers. In addition, LOX transgenesis increased the Ang II-induced myocardial inflammatory infiltrate, exacerbated expression of proinflammatory markers, and decreased that of cardioprotective factors. Mechanistically, LOX overexpression enhanced oxidative stress and potentiated the Ang II-mediated cardiac activation of p38 MAPK while reducing AMPK activation. Our findings suggest that LOX induces an age-dependent disturbance of diastolic function and aggravates Ang II-induced hypertrophy, which provides novel insights into the role of LOX in cardiac performance.-Galán, M., Varona, S., Guadall, A., Orriols, M., Navas, M., Aguiló, S., de Diego, A., Navarro, M. A., García-Dorado, D., Rodríguez-Sinovas, A., Martínez-González, J., Rodriguez, C. Lysyl oxidase overexpression accelerates cardiac remodeling and aggravates angiotensin II-induced hypertrophy. © FASEB.

  7. Overexpression and deletion of phospholipid transfer protein reduce HDL mass and cholesterol efflux capacity but not macrophage reverse cholesterol transport[S

    Science.gov (United States)

    Kuwano, Takashi; Bi, Xin; Cipollari, Eleonora; Yasuda, Tomoyuki; Lagor, William R.; Szapary, Hannah J.; Tohyama, Junichiro; Millar, John S.; Billheimer, Jeffrey T.; Lyssenko, Nicholas N.; Rader, Daniel J.

    2017-01-01

    Phospholipid transfer protein (PLTP) may affect macrophage reverse cholesterol transport (mRCT) through its role in the metabolism of HDL. Ex vivo cholesterol efflux capacity and in vivo mRCT were assessed in PLTP deletion and PLTP overexpression mice. PLTP deletion mice had reduced HDL mass and cholesterol efflux capacity, but unchanged in vivo mRCT. To directly compare the effects of PLTP overexpression and deletion on mRCT, human PLTP was overexpressed in the liver of wild-type animals using an adeno-associated viral (AAV) vector, and control and PLTP deletion animals were injected with AAV-null. PLTP overexpression and deletion reduced plasma HDL mass and cholesterol efflux capacity. Both substantially decreased ABCA1-independent cholesterol efflux, whereas ABCA1-dependent cholesterol efflux remained the same or increased, even though preβ HDL levels were lower. Neither PLTP overexpression nor deletion affected excretion of macrophage-derived radiocholesterol in the in vivo mRCT assay. The ex vivo and in vivo assays were modified to gauge the rate of cholesterol efflux from macrophages to plasma. PLTP activity did not affect this metric. Thus, deviations in PLTP activity from the wild-type level reduce HDL mass and ex vivo cholesterol efflux capacity, but not the rate of macrophage cholesterol efflux to plasma or in vivo mRCT. PMID:28137768

  8. Impaired chemosensitivity of mouse dorsal raphe serotonergic neurons overexpressing serotonin 1A (Htr1a receptors.

    Directory of Open Access Journals (Sweden)

    Gilda Baccini

    Full Text Available BACKGROUND: Serotonergic system participates in a wide range of physiological processes and behaviors, but its role is generally considered as modulatory and noncrucial, especially concerning life-sustaining functions. We recently created a transgenic mouse line in which a functional deficit in serotonin homeostasis due to excessive serotonin autoinhibition was produced by inducing serotonin 1A receptor (Htr1a overexpression selectively in serotonergic neurons (Htr1a raphe-overexpressing or Htr1a(RO mice. Htr1a(RO mice exhibit episodes of autonomic dysregulation, cardiovascular crises and death, resembling those of sudden infant death syndrome (SIDS and revealing a life-supporting role of serotonergic system in autonomic control. Since midbrain serotonergic neurons are chemosensitive and are implicated in arousal we hypothesized that their chemosensitivity might be impaired in Htr1a(RO mice. PRINCIPAL FINDINGS: Loose-seal cell-attached recordings in brainstem slices revealed that serotonergic neurons in dorsal raphe nucleus of Htr1a(RO mice have dramatically reduced responses to hypercapnic challenge as compared with control littermates. In control mice, application of 9% CO(2 produced an increase in firing rate of serotonergic neurons (0.260 ± 0.041 Hz, n=20, p=0.0001 and application of 3% CO(2 decreased their firing rate (-0.142 ± 0.025 Hz, n=17, p=0.0008. In contrast, in Htr1a(RO mice, firing rate of serotonergic neurons was not significantly changed by 9% CO(2 (0.021 ± 0.034 Hz, n=16, p=0.49 and by 3% CO(2 (0.012 ± 0.046 Hz, n=12, p=0.97. CONCLUSIONS: Our findings support the hypothesis that chemosensitivity of midbrain serotonergic neurons provides a physiological mechanism for arousal responses to life-threatening episodes of hypercapnia and that functional impairment, such as excessive autoinhibition, of midbrain serotonergic neuron responses to hypercapnia may contribute to sudden death.

  9. Overexpression of osteoprotegerin promotes preosteoblast differentiation to mature osteoblasts

    NARCIS (Netherlands)

    Yu, Hongyou; de Vos, Paul; Ren, Yijin

    OBJECTIVE: The hypothesis of the present study is that overexpression of osteoprotegerin (OPG) promotes preosteoblast maturation. MATERIALS AND METHODS: The preosteoblast cell line MC3T3-E1 was transfected with OPG overexpression. OPG expression was confirmed by enzyme-linked immunosorbent assay

  10. Fbxl10 overexpression in murine hematopoietic stem cells induces leukemia involving metabolic activation and upregulation of Nsg2

    DEFF Research Database (Denmark)

    Ueda, Takeshi; Nagamachi, Akiko; Takubo, Keiyo

    2015-01-01

    investigate the role of Fbxl10 in leukemogenesis, we generated transgenic (Tg) mice that overexpress Fbxl10 in hematopoietic stem cells (HSCs). Interestingly, Fbxl10 Tg mice developed myeloid or B-lymphoid leukemia with complete penetrance. HSCs from the Tg mice exhibited an accelerated G0/G1 to S transition...... with a normal G0 to G1 entry, resulting in pleiotropic progenitor cell expansion. Fbxl10 Tg HSCs displayed enhanced expression of neuron specific gene family member 2 (Nsg2) and forced expression of Nsg2 in primary bone marrow cells resulted in expansion of immature cells. In addition, the genes involved...... in mitochondrial oxidative phosphorylation were markedly enriched in Fbxl10 Tg HSCs, coupled with increased cellular ATP levels. Moreover, chromatin immunoprecipitation followed by sequencing analysis demonstrated that Fbxl10 directly binds to the regulatory regions of Nsg2 and oxidative phosphorylation genes...

  11. [Establishment and identification of Jurkat cell xenograft mouse models with over-expression of C-terminal Src kinase binding protein].

    Science.gov (United States)

    Gao, Meihua; Ma, Yu; Wang, Bing; Zhang, Bei; Zhang, Minrui; Zhang, Shuchao

    2015-09-01

    To establish xenograft mouse models of Jurkat T-leukemia cells over-expressing C-terminal Src kinase binding protein (CBP). The 5-week-old female BALB/c-nu mice were randomly divided into blank control group, normal Jurkat cell control group, empty virus-transfected Jurkat cell control group and CBP over-expression model group, 5 mice in each group. The mice were subcutaneously injected 1×10(7)/0.1 mL Jurkat cells in axillary area. The tumor tissues of mouse models were weighed and then subjected to HE staining to observe the pathological changes of tumor tissues. The proliferation of Jurkat cells in the peripheral blood of mice was detected by flow cytometry, and the interleukin 2 (IL-2) levels in mouse sera were determined with ELISA. The volume of tumor tissues in the CBP over-expression model group was smaller than that in the control groups, so was the mass of tumor tissues. HE staining showed the proliferation of Jurkat cells in tumor tissues of the model group. The proliferation rate of Jurkat cells in the peripheral blood and IL-2 levels in the sera of the CBP over-expression model group were lower than those in the normal Jurkat cell control group and the empty virus-transfected Jurkat cell control group. The mouse models of Jurkat T-leukemia cells over-expressing CBP have been established successfully. Up-regulated CBP has inhibitory effects on the proliferation of Jurkat cells and IL-2 secretion.

  12. A new anti-tumor strategy based on in vivo tumstatin overexpression after plasmid electrotransfer in muscle

    International Nuclear Information System (INIS)

    Thevenard, Jessica; Ramont, Laurent; Mir, Lluis M.; Dupont-Deshorgue, Aurélie; Maquart, François-Xavier; Monboisse, Jean-Claude; Brassart-Pasco, Sylvie

    2013-01-01

    Highlights: ► A new therapeutic strategy based on tumstatin in vivo overexpression is proposed. ► pVAX1©–tumstatin electrotransfer in muscle mediates protein expression in muscle. ► A substantial expression of tumstatin is detected in the serum of electrotransfected mice. ► Tumstatin overexpression decreases tumor growth and increases mouse survival. -- Abstract: The NC1 domains from the different α(IV) collagen chains were found to exert anti-tumorigenic and/or anti-angiogenic activities. A limitation to the therapeutic use of these matrikines is the large amount of purified recombinant proteins, in the milligram range in mice that should be administered daily throughout the experimental procedures. In the current study, we developed a new therapeutic approach based on tumstatin (NC1α3(IV)) overexpression in vivo in a mouse melanoma model. Gene electrotransfer of naked plasmid DNA (pDNA) is particularly attractive because of its simplicity, its lack of immune responsiveness and its safety. The pDNA electrotransfer in muscle mediates a substantial gene expression that lasts several months. A pVAX1© vector containing the tumstatin cDNA was injected into the legs of C57BL/6 mice and submitted to electrotranfer. Sera were collected at different times and tumstatin was quantified by ELISA. Tumstatin secretion reached a plateau at day 21 with an expression level of 12 μg/mL. For testing the effects of tumstatin expression on tumor growth in vivo, B16F1 melanoma cells were subcutaneously injected in mice 7 days after empty pVAX1© (Mock) or pVAX1©–tumstatin electrotransfer. Tumstatin expression triggered a large decrease in tumor growth and an increase in mouse survival. This new therapeutic approach seems promising to inhibit tumor progression in vivo

  13. Chronic overexpression of cerebral Epo improves the ventilatory response to acute hypoxia during the postnatal development.

    Science.gov (United States)

    Caravagna, Céline; Schneider Gasser, Edith M; Ballot, Orlane; Joseph, Vincent; Soliz, Jorge

    2015-08-01

    Clinicians observed that the treatment of premature human newborns for anemia with erythropoietin (Epo) also improved their respiratory autonomy. This observation is in line with our previous in vitro studies showing that acute and chronic Epo stimulation enhances fictive breathing of brainstem-spinal cord preparations of postnatal day 3-4 mice during hypoxia. Furthermore, we recently reported that the antagonization of the cerebral Epo (by using the soluble Epo receptor; sEpoR) significantly reduced the basal ventilation and the hypoxic ventilatory response of 10 days old mice. In this study, we used transgenic (Tg21) mice to investigate the effect of the chronic cerebral Epo overexpression on the modulation of the normoxic and hypoxic ventilatory drive during the post-natal development. Ventilation was evaluated by whole body plethysmography at postnatal ages 3 (P3), 7 (P7), 15 (P15) and 21 (P21). In addition Epo quantification was performed by RIA and mRNA EpoR was evaluated by qRT-PCR. Our results showed that compared to control animals the chronic Epo overexpression stimulates the hypoxic (but not the normoxic) ventilation assessed as VE/VO2 at the ages of P3 and P21. More interestingly, we observed that at P7 and P15 the chronic Epo stimulation of ventilation was attenuated by the down regulation of the Epo receptor in brainstem areas. We conclude that Epo, by stimulating ventilation in brainstem areas crucially helps tolerating physiological (e.g., high altitude) and/or pathological (e.g., respiratory disorders, prematurity, etc.) oxygen deprivation at postnatal ages. Copyright © 2015 ISDN. Published by Elsevier Ltd. All rights reserved.

  14. Smooth Muscle-Targeted Overexpression of Peroxisome Proliferator Activated Receptor-γ Disrupts Vascular Wall Structure and Function.

    Directory of Open Access Journals (Sweden)

    Jennifer M Kleinhenz

    Full Text Available Activation of the nuclear hormone receptor, PPARγ, with pharmacological agonists promotes a contractile vascular smooth muscle cell phenotype and reduces oxidative stress and cell proliferation, particularly under pathological conditions including vascular injury, restenosis, and atherosclerosis. However, pharmacological agonists activate both PPARγ-dependent and -independent mechanisms in multiple cell types confounding efforts to clarify the precise role of PPARγ in smooth muscle cell structure and function in vivo. We, therefore, designed and characterized a mouse model with smooth muscle cell-targeted PPARγ overexpression (smPPARγOE. Our results demonstrate that smPPARγOE attenuated contractile responses in aortic rings, increased aortic compliance, caused aortic dilatation, and reduced mean arterial pressure. Molecular characterization revealed that compared to littermate control mice, aortas from smPPARγOE mice expressed lower levels of contractile proteins and increased levels of adipocyte-specific transcripts. Morphological analysis demonstrated increased lipid deposition in the vascular media and in smooth muscle of extravascular tissues. In vitro adenoviral-mediated PPARγ overexpression in human aortic smooth muscle cells similarly increased adipocyte markers and lipid uptake. The findings demonstrate that smooth muscle PPARγ overexpression disrupts vascular wall structure and function, emphasizing that balanced PPARγ activity is essential for vascular smooth muscle homeostasis.

  15. Overexpression of CXCR4 on human CD34+ progenitors increases their proliferation, migration, and NOD/SCID repopulation.

    Science.gov (United States)

    Kahn, Joy; Byk, Tamara; Jansson-Sjostrand, Lottie; Petit, Isabelle; Shivtiel, Shoham; Nagler, Arnon; Hardan, Izhar; Deutsch, Varda; Gazit, Zulma; Gazit, Dan; Karlsson, Stefan; Lapidot, Tsvee

    2004-04-15

    A major limitation to clinical stem cell-mediated gene therapy protocols is the low levels of engraftment by transduced progenitors. We report that CXCR4 overexpression on human CD34+ progenitors using a lentiviral gene transfer technique helped navigate these cells to the murine bone marrow and spleen in response to stromal-derived factor 1 (SDF-1) signaling. Cells overexpressing CXCR4 exhibited significant increases in SDF-1-mediated chemotaxis and actin polymerization compared with control cells. A major advantage of CXCR4 overexpression was demonstrated by the ability of transduced CD34+ cells to respond to lower, physiologic levels of SDF-1 when compared to control cells, leading to improved SDF-1-induced migration and proliferation/survival, and finally resulting in significantly higher levels of in vivo repopulation of nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice including primitive CD34+/CD38(-/low) cells. Importantly, no cellular transformation was observed following transduction with the CXCR4 vector. Unexpectedly, we documented lack of receptor internalization in response to high levels of SDF-1, which can also contribute to increased migration and proliferation by the transduced CD34+ cells. Our results suggest CXCR4 overexpression for improved definitive human stem cell motility, retention, and multilineage repopulation, which could be beneficial for in vivo navigation and expansion of hematopoietic progenitors.

  16. Sirtuin1 over-expression does not impact retinal vascular and neuronal degeneration in a mouse model of oxygen-induced retinopathy.

    Directory of Open Access Journals (Sweden)

    Shaday Michan

    Full Text Available Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1, a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR, as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy.

  17. Sirtuin1 over-expression does not impact retinal vascular and neuronal degeneration in a mouse model of oxygen-induced retinopathy.

    Science.gov (United States)

    Michan, Shaday; Juan, Aimee M; Hurst, Christian G; Cui, Zhenghao; Evans, Lucy P; Hatton, Colman J; Pei, Dorothy T; Ju, Meihua; Sinclair, David A; Smith, Lois E H; Chen, Jing

    2014-01-01

    Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy.

  18. Oncogenic properties of a novel gene JK-1 located in chromosome 5p and its overexpression in human esophageal squamous cell carcinoma.

    Science.gov (United States)

    Tang, Wing K; Chui, Chung H; Fatima, Sarwat; Kok, Stanton H L; Pak, Kai C; Ou, Tian M; Hui, Kin S; Wong, Mei M; Wong, John; Law, Simon; Tsao, S W; Lam, King Y; Beh, Philip S L; Srivastava, Gopesh; Chan, Albert S C; Ho, Kwok P; Tang, Johnny C O

    2007-06-01

    Esophageal squamous cell carcinoma (ESCC) shows high frequency and mortality in Asian regions, including China. Previous analysis of genomic DNA of ESCC using comparative genomic hybridization indicated that amplification of the chromosome 5p regions is a common event in ESCC cell lines and patient cases of Hong Kong Chinese origin, and the results suggested that the genes located in the chromosome 5p regions may play crucial roles in the molecular pathogenesis of ESCC. Our previous studies on ESCC confirmed the tumorigenic and overexpression properties of a novel gene JS-1 located in chromosome 5p15.2 upstream to delta-catenin. In the present study, another novel gene JK-1 which is located at 5p15.1 downstream to delta-catenin was characterized for its roles in the pathogenesis of ESCC. Thirteen ESCC cell lines and 30 surgical specimens of esophageal tumors were studied for the overexpression of JK-1 using multiplex RT-PCR analysis. The transforming capacity of overexpression of JK-1 was also investigated by transfecting NIH 3T3 and HEK 293 cells with the expression vector cloned with JK-1, followed by the soft agar and foci formation assays. JK-1 was overexpressed in 9/13 (69%) of the ESCC cell lines and 9/30 (30%) of the ESCC patient cases. Both NIH 3T3 and HEK 293 cells acquired the properties of anchorage-dependent and -independent growth when JK-1 was overexpressed. Most significantly, subcutaneous sarcomas were formed in all (3/3) the athymic nude mice after NIH 3T3 cells overexpressing JK-1 were injected subcutaneously. Our results thus indicated that JK-1 is commonly overexpressed in ESCC and has a prominent capacity to transform normal cells. Our overall results thus provide the first evidence that the overexpression of JK-1 and its transforming capacity in normal cells may play a critical role in the molecular pathogenesis of ESCC.

  19. Parvalbumin overexpression alters immune-mediated increases in intracellular calcium, and delays disease onset in a transgenic model of familial amyotrophic lateral sclerosis

    Science.gov (United States)

    Beers, D. R.; Ho, B. K.; Siklos, L.; Alexianu, M. E.; Mosier, D. R.; Mohamed, A. H.; Otsuka, Y.; Kozovska, M. E.; McAlhany, R. E.; Smith, R. G.; hide

    2001-01-01

    Intracellular calcium is increased in vulnerable spinal motoneurons in immune-mediated as well as transgenic models of amyotrophic lateral sclerosis (ALS). To determine whether intracellular calcium levels are influenced by the calcium-binding protein parvalbumin, we developed transgenic mice overexpressing parvalbumin in spinal motoneurons. ALS immunoglobulins increased intracellular calcium and spontaneous transmitter release at motoneuron terminals in control animals, but not in parvalbumin overexpressing transgenic mice. Parvalbumin transgenic mice interbred with mutant SOD1 (mSOD1) transgenic mice, an animal model of familial ALS, had significantly reduced motoneuron loss, and had delayed disease onset (17%) and prolonged survival (11%) when compared with mice with only the mSOD1 transgene. These results affirm the importance of the calcium binding protein parvalbumin in altering calcium homeostasis in motoneurons. The increased motoneuron parvalbumin can significantly attenuate the immune-mediated increases in calcium and to a lesser extent compensate for the mSOD1-mediated 'toxic-gain-of-function' in transgenic mice.

  20. Over-expression of adenosine deaminase in mouse podocytes does not reverse puromycin aminonucleoside resistance

    Directory of Open Access Journals (Sweden)

    Doucet Alain

    2010-07-01

    Full Text Available Abstract Background Edema in nephrotic syndrome results from renal retention of sodium and alteration of the permeability properties of capillaries. Nephrotic syndrome induced by puromycin aminonucleoside (PAN in rats reproduces the biological and clinical signs of the human disease, and has been widely used to identify the cellular mechanisms of sodium retention. Unfortunately, mice do not develop nephrotic syndrome in response to PAN, and we still lack a good mouse model of the disease in which the genetic tools necessary for further characterizing the pathophysiological pathway could be used. Mouse resistance to PAN has been attributed to a defect in glomerular adenosine deaminase (ADA, which metabolizes PAN. We therefore attempted to develop a mouse line sensitive to PAN through induction of normal adenosine metabolism in their podocytes. Methods A mouse line expressing functional ADA under the control of the podocyte-specific podocin promoter was generated by transgenesis. The effect of PAN on urinary excretion of sodium and proteins was compared in rats and in mice over-expressing ADA and in littermates. Results We confirmed that expression of ADA mRNAs was much lower in wild type mouse than in rat glomerulus. Transgenic mice expressed ADA specifically in the glomerulus, and their ADA activity was of the same order of magnitude as in rats. Nonetheless, ADA transgenic mice remained insensitive to PAN treatment in terms of both proteinuria and sodium retention. Conclusions Along with previous results, this study shows that adenosine deaminase is necessary but not sufficient to confer PAN sensitivity to podocytes. ADA transgenic mice could be used as a background strain for further transgenesis.

  1. C-MET overexpression and amplification in gliomas.

    Science.gov (United States)

    Kwak, Yoonjin; Kim, Seong-Ik; Park, Chul-Kee; Paek, Sun Ha; Lee, Soon-Tae; Park, Sung-Hye

    2015-01-01

    We investigated c-Met overexpression and MET gene amplification in gliomas to determine their incidence and prognostic significance. c-Met immunohistochemistry and MET gene fluorescence in situ hybridization were carried out on tissue microarrays from 250 patients with gliomas (137 grade IV GBMs and 113 grade II and III diffuse gliomas). Clinicopathological features of these cases were reviewed. c-Met overexpression and MET gene amplification were detected in 13.1% and 5.1% of the GBMs, respectively. All the MET-amplified cases showed c-Met overexpression, but MET amplification was not always concordant with c-Met overexpression. None of grade II and III gliomas demonstrated c-Met overexpression or MET gene amplification. Mean survival of the GBM patients with MET amplification was not significantly different from patients without MET amplification (P=0.155). However, GBM patients with c-Met overexpression survived longer than patients without c-Met overexpression (P=0.035). Although MET amplification was not related to poor GBM prognosis, it is partially associated with the aggressiveness of gliomas, as MET amplification was found only in grade IV, not in grade II and III gliomas. We suggest that MET inhibitor therapy may be beneficial in about 5% GBMs, which was the incidence of MET gene amplification found in the patients included in this study.

  2. Overexpression of the mitochondrial methyltransferase TFB1M in the mouse does not impact mitoribosomal methylation status or hearing

    DEFF Research Database (Denmark)

    Lee, Seungmin; Rose, Simon; Metodiev, Metodi D

    2015-01-01

    Mitochondrial dysfunction is a well-established cause of sensorineural deafness, but the pathophysiological events are poorly understood. Non-syndromic deafness and predisposition to aminoglycoside-induced deafness can be caused by specific mutations in the 12S rRNA gene of mtDNA and are thus...... by 'hypermethylation' of two conserved adenosines of 12S rRNA in the mitoribosome is of key pathophysiological importance in sensorineural deafness. In support for this concept, it was reported that overexpression of the essential mitochondrial methyltransferase TFB1M in the mouse was sufficient to induce...... mitoribosomal hypermethylation and deafness. At variance with this model, we show here that 12S rRNA is near fully methylated in vivo in the mouse and thus cannot be further methylated to any significant extent. Furthermore, bacterial artificial chromosome transgenic mice overexpressing TFB1M have no increase...

  3. Progressive Metaplastic and Dysplastic Changes in Mouse Pancreas Induced by Cyclooxygenase-2 Overexpression

    Directory of Open Access Journals (Sweden)

    Jennifer K.L. Colby

    2008-08-01

    Full Text Available Cyclooxygenase-2 (COX-2 overexpression is an established factor linking chronic inflammation with metaplastic and neoplastic change in various tissues. We generated transgenic mice (BK5.COX-2 in which elevation of COX-2 and its effectors trigger a metaplasia-dysplasia sequence in exocrine pancreas. Histologic evaluation revealed a chronic pancreatitis-like state characterized by acinar-to-ductal metaplasia and a well-vascularized fibroinflammatory stroma that develops by 3 months. By 6 to 8 months, strongly dysplastic features suggestive of pancreatic ductal adenocarcinoma emerge in the metaplastic ducts. Increased proliferation, cellular atypia, and loss of normal cell/tissue organization are typical features in transgenic pancreata. Alterations in biomarkers associated with human inflammatory and neoplastic pancreatic disease were detected using immunohistochemistry. The abnormal pancreatic phenotype can be completely prevented by maintaining mice on a diet containing celecoxib, a well-characterized COX-2 inhibitor. Despite the high degree of atypia, only limited evidence of invasion to adjacent tissues was observed, with no evidence of distant metastases. However, cell lines derived from spontaneous lesions are aggressively tumorigenic when injected into syngeneic or nude mice. The progressive nature of the metaplastic/dysplastic changes observed in this model make it a valuable tool for examining the transition from chronic inflammation to neoplasia.

  4. Metabolic hormone FGF21 is induced in ground squirrels during hibernation but its overexpression is not sufficient to cause torpor.

    Directory of Open Access Journals (Sweden)

    Bethany T Nelson

    Full Text Available Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that are lethal to humans. Near freezing body temperatures, heart rates of 3-10 beats per minute, absence of food consumption, and depressed metabolism are characteristic of hibernation torpor bouts that are periodically interrupted by brief interbout arousals (IBAs. The molecular basis of torpor induction is unknown, however starved mice overexpressing the metabolic hormone fibroblast growth factor 21 (FGF21 promote fat utilization, reduce body temperature, and readily enter torpor-all hallmarks of mammalian hibernation. In this study we cloned FGF21 from the naturally hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus and found that levels of FGF21 mRNA in liver and FGF21 protein in serum are elevated during hibernation torpor bouts and significantly elevated during IBAs compared to summer active animals. The effects of artificially elevating circulating FGF21 concentrations 50 to 100-fold via adenoviral-mediated overexpression were examined at three different times of the year. This is the first time that a transgenic approach has been used in a natural hibernator to examine mechanistic aspects of hibernation. Surgically implanted transmitters measured various metrics of the hibernation phenotype over a 7-day period including changes in motor activity, heart rate and core body temperature. In April fed-state animals, FGF21 overexpression decreased blood insulin and free fatty acid concentrations, effects similar to those seen in obese mice. However, elevated FGF21 concentrations did not cause torpor in these fed-state animals nor did they cause torpor or affect metabolic parameters in fasted-state animals in March/April, August or October. We conclude that FGF21 is strongly regulated during torpor and IBA but that its overexpression is not sufficient to cause torpor in naturally hibernating ground squirrels.

  5. Metabolic hormone FGF21 is induced in ground squirrels during hibernation but its overexpression is not sufficient to cause torpor.

    Science.gov (United States)

    Nelson, Bethany T; Ding, Xunshan; Boney-Montoya, Jamie; Gerard, Robert D; Kliewer, Steven A; Andrews, Matthew T

    2013-01-01

    Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that are lethal to humans. Near freezing body temperatures, heart rates of 3-10 beats per minute, absence of food consumption, and depressed metabolism are characteristic of hibernation torpor bouts that are periodically interrupted by brief interbout arousals (IBAs). The molecular basis of torpor induction is unknown, however starved mice overexpressing the metabolic hormone fibroblast growth factor 21 (FGF21) promote fat utilization, reduce body temperature, and readily enter torpor-all hallmarks of mammalian hibernation. In this study we cloned FGF21 from the naturally hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus) and found that levels of FGF21 mRNA in liver and FGF21 protein in serum are elevated during hibernation torpor bouts and significantly elevated during IBAs compared to summer active animals. The effects of artificially elevating circulating FGF21 concentrations 50 to 100-fold via adenoviral-mediated overexpression were examined at three different times of the year. This is the first time that a transgenic approach has been used in a natural hibernator to examine mechanistic aspects of hibernation. Surgically implanted transmitters measured various metrics of the hibernation phenotype over a 7-day period including changes in motor activity, heart rate and core body temperature. In April fed-state animals, FGF21 overexpression decreased blood insulin and free fatty acid concentrations, effects similar to those seen in obese mice. However, elevated FGF21 concentrations did not cause torpor in these fed-state animals nor did they cause torpor or affect metabolic parameters in fasted-state animals in March/April, August or October. We conclude that FGF21 is strongly regulated during torpor and IBA but that its overexpression is not sufficient to cause torpor in naturally hibernating ground squirrels.

  6. Overexpression of Hoxc13 in differentiating keratinocytes results in downregulation of a novel hair keratin gene cluster and alopecia.

    Science.gov (United States)

    Tkatchenko, A V; Visconti, R P; Shang, L; Papenbrock, T; Pruett, N D; Ito, T; Ogawa, M; Awgulewitsch, A

    2001-05-01

    Studying the roles of Hox genes in normal and pathological development of skin and hair requires identification of downstream target genes in genetically defined animal models. We show that transgenic mice overexpressing Hoxc13 in differentiating keratinocytes of hair follicles develop alopecia, accompanied by a progressive pathological skin condition that resembles ichthyosis. Large-scale analysis of differential gene expression in postnatal skin of these mice identified 16 previously unknown and 13 known genes as presumptive Hoxc13 targets. The majority of these targets are downregulated and belong to a subgroup of genes that encode hair-specific keratin-associated proteins (KAPs). Genomic mapping using a mouse hamster radiation hybrid panel showed these genes to reside in a novel KAP gene cluster on mouse chromosome 16 in a region of conserved linkage with human chromosome 21q22.11. Furthermore, data obtained by Hoxc13/lacZ reporter gene analysis in mice that overexpress Hoxc13 suggest negative autoregulatory feedback control of Hoxc13 expression levels, thus providing an entry point for elucidating currently unknown mechanisms that are required for regulating quantitative levels of Hox gene expression. Combined, these results provide a framework for understanding molecular mechanisms of Hoxc13 function in hair growth and development.

  7. Phenotypic effects of membrane protein overexpression in Saccharomyces cerevisiae

    Science.gov (United States)

    Melén, Karin; Blomberg, Anders; von Heijne, Gunnar

    2006-07-01

    Large-scale protein overexpression phenotype screens provide an important complement to the more common gene knockout screens. Here, we have targeted the so far poorly understood Saccharomyces cerevisiae membrane proteome and report growth phenotypes for a strain collection overexpressing 600 C-terminally tagged integral membrane proteins grown both under normal and three different stress conditions. Although overexpression of most membrane proteins reduce the growth rate in synthetic defined medium, we identify a large number of proteins that, when overexpressed, confer specific resistance to various stress conditions. Our data suggest that regulation of glycosylphosphatidylinositol anchor biosynthesis and the Na+/K+ homeostasis system constitute major downstream targets of the yeast PKA/RAS pathway and point to a possible connection between the early secretory pathway and the cells' response to oxidative stress. We also have quantified the expression levels for >550 membrane proteins, facilitating the choice of well expressing proteins for future functional and structural studies. caffeine | paraquat | salt tolerance | yeast

  8. [Overexpression of FKS1 to improve yeast autolysis-stress].

    Science.gov (United States)

    Li, Jia; Wang, Jinjing; Li, Qi

    2015-09-01

    With the development of high gravity brewing, yeast cells are exposed to multiple brewing-associated stresses, such as increased osmotic pressure, enhanced alcohol concentration and nutritional imbalance. These will speed up yeast autolysis, which seriously influence beer flavor and quality. To increase yeast anti-autolytic ability, FKS1 overexpression strain was constructed by 18S rDNA. The concentration of β-1,3-glucan of overexpression strain was 62% higher than that of wild type strain. Meantime, FKS1 overexpression strain increased anti-stress ability at 8% ethanol, 0.4 mol/L NaCl and starvation stress. Under simulated autolysis, FKS1 showed good anti-autolytic ability by slower autolysis. These results confirms the potential of FKS1 overexpression to tackle yeast autolysis in high-gravity brewing.

  9. Trib1 Is Overexpressed in Systemic Lupus Erythematosus, While It Regulates Immunoglobulin Production in Murine B Cells

    Directory of Open Access Journals (Sweden)

    Léa Simoni

    2018-03-01

    Full Text Available Systemic lupus erythematosus (SLE is a severe and heterogeneous autoimmune disease with a complex genetic etiology, characterized by the production of various pathogenic autoantibodies, which participate in end-organ damages. The majority of human SLE occurs in adults as a polygenic disease, and clinical flares interspersed with silent phases of various lengths characterize the usual evolution of the disease in time. Trying to understand the mechanism of the different phenotypic traits of the disease, and considering the central role of B cells in SLE, we previously performed a detailed wide analysis of gene expression variation in B cells from quiescent SLE patients. This analysis pointed out an overexpression of TRIB1. TRIB1 is a pseudokinase that has been implicated in the development of leukemia and also metabolic disorders. It is hypothesized that Trib1 plays an adapter or scaffold function in signaling pathways, notably in MAPK pathways. Therefore, we planned to understand the functional significance of TRIB1 overexpression in B cells in SLE. We produced a new knock-in model with B-cell-specific overexpression of Trib1. We showed that overexpression of Trib1 specifically in B cells does not impact B cell development nor induce any development of SLE symptoms in the mice. By contrast, Trib1 has a negative regulatory function on the production of immunoglobulins, notably IgG1, but also on the production of autoantibodies in an induced model. We observed a decrease of Erk activation in BCR-stimulated Trib1 overexpressing B cells. Finally, we searched for Trib1 partners in B cells by proteomic analysis in order to explore the regulatory function of Trib1 in B cells. Interestingly, we find an interaction between Trib1 and CD72, a negative regulator of B cells whose deficiency in mice leads to the development of autoimmunity. In conclusion, the overexpression of Trib1 could be one of the molecular pathways implicated in the negative regulation

  10. Myocardial overexpression of TIMP3 after myocardial infarction exerts beneficial effects by promoting angiogenesis and suppressing early proteolysis.

    Science.gov (United States)

    Takawale, Abhijit; Zhang, Pu; Azad, Abul; Wang, Wang; Wang, Xiuhua; Murray, Allan G; Kassiri, Zamaneh

    2017-08-01

    Myocardial infarction (MI) results in loss of cardiomyocytes, adverse extracellular matrix (ECM) and structural remodeling, and left ventricular (LV) dilation and dysfunction. Tissue inhibitors of metalloproteinase (TIMPs) inhibit matrix metalloproteinases (MMPs), the main regulators of ECM turnover. TIMPs also have MMP-independent functions. TIMP3 levels are reduced in the heart within 24 h of MI in mice. We investigated if overexpression of TIMP3 post-MI limits adverse remodeling and LV dilation and dysfunction. MI was induced by left anterior descending coronary artery ligation in 10- to 12-wk-old male C57BL/6J mice, and adenoviral constructs expressing human (h)TIMP3 (Ad-hTIMP3) or no TIMP (Ad-Null) were injected in the peri-infarct zone (5.4 × 10 7 plaque-forming units/heart, 5 injections/heart). Cardiac function assessed by echocardiography showed improved LV physiology and reduced LV dilation after TIMP3 overexpression compared with the Ad-Null-MI group. Post-MI adverse remodeling was attenuated in the Ad-hTIMP3-MI group, as assessed by greater cardiomyocyte density, less infarct expansion, and ECM disruption. TIMP3 overexpression blunted the early rise in proteolytic activities post-MI. A higher density of coronary arteries and a greater number of proliferating endothelial cells were detected in the infarct and peri-infarct regions in the Ad-hTIMP3-MI group compared with the Ad-Null-MI group. In vitro three-dimensional angiogenesis assay confirmed that recombinant TIMP3 promotes angiogenesis in human endothelial cells, although biphasically and in a dose-dependent manner. Intriguingly, overexpression of Ad-hTIMP3 at 10-fold higher concentration had no beneficial effects, consistent with antiangiogenic effects of TIMP3 at higher doses. In conclusion, optimal overexpression of TIMP3 can be a promising therapeutic approach to limit adverse post-MI remodeling by dually inhibiting early proteolysis and promoting angiogenesis. NEW & NOTEWORTHY Here, we report

  11. The protective effect of PRMT6 overexpression on cigarette smoke extract-induced murine emphysema model

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    He X

    2017-11-01

    Full Text Available Xue He,1–3 Tiao Li,1–3 Naixin Kang,1–3 Huihui Zeng,1–3 Siying Ren,1–3 Dandan Zong,1–3 Jinhua Li,1–3 Shan Cai,1–3 Ping Chen,1–3 Yan Chen1–3 1Department of Respiratory Medicine, The Second Xiangya Hospital, 2Research Unit of Respiratory Disease, 3Diagnosis and Treatment Center of Respiratory Disease, Central South University, Changsha, Hunan, China Background: Cigarette smoke exposure is the most common risk factor for emphysema, which is one of the major pathologies of COPD. Protein arginine methyltransferase 6 (PRMT6 is a nuclear enzyme that specially catalyzes dimethylation of R2 in histone H3 (H3R2me2a. H3R2me2a prevents trimethylation of H3K4 (H3K4me3, which is located in the transcription start sites of genes in mammalian genomes. We attempted to determine the expression of PRMT6 in human samples, and investigate whether the upregulation of PRMT6 expression can attenuate the development of cigarette smoke extract (CSE-induced emphysema. Further experiments were performed to elucidate the molecular mechanisms involved.Materials and methods: Human lung tissues were obtained from patients undergoing pneumonectomy for benign pulmonary lesions. BALB/c mice were treated with lentiviral vectors intratracheally and injected with CSE three times. The protein expression of PRMT6, H3R2me2a, and H3K4me3 in human and mouse samples, as well as B-cell lymphoma-2 (Bcl-2, Bcl-2-associated X protein (Bax, and endothelial nitric oxide synthase (eNOS in mice were detected in lung homogenates by Western blotting. The mRNA expression of cyclooxygenase-2, interleukin-6, Bcl-2, Bax, and eNOS in mice was measured by quantitative real-time polymerase chain reaction.Results: The expression of PRMT6 was significantly downregulated in the pulmonary parenchyma in smokers with COPD as well as in mice treated with CSE. Overexpression of PRMT6 was detected in the CSE + Lenti-PRMT6 group of mice, which reversed the expression of H3R2me2a and H3K4me3

  12. In vivo overexpression of tumstatin domains by tumor cells inhibits their invasive properties in a mouse melanoma model

    International Nuclear Information System (INIS)

    Pasco, Sylvie; Ramont, Laurent; Venteo, Lydie; Pluot, Michel; Maquart, Francois-Xavier; Monboisse, Jean-Claude

    2004-01-01

    Our previous studies demonstrated that a synthetic peptide encompassing residues 185-203 of the noncollagenous (NC1) domain of the α3 chain of type IV collagen, named tumstatin, inhibits in vitro melanoma cell proliferation and migration. In the present study, B16F1 melanoma cells were stably transfected to overexpress the complete tumstatin domain (Tum 1-232) or its C-terminal part, encompassing residues 185-203 (Tum 183-232). Tumstatin domain overexpression inhibited B16F1 in vitro cell proliferation, anchorage-independent growth, and invasive properties. For studying the in vivo effect of overexpression, representative clones were subcutaneously injected into the left side of C57BL6 mice. In vivo tumor growth was decreased by -60% and -56%, respectively, with B16F1 cells overexpressing Tum 1-232 or Tum 183-232 compared to control cells. This inhibitory effect was associated with a decrease of in vivo cyclin D1 expression. We also demonstrated that the overexpression of Tum 1-232 or Tum 183-232 induced an in vivo down-regulation of proteolytic cascades involving matrix metalloproteinases (MMPs), especially the production or activation of MMP-2, MMP-9, MMP-13, as well as MMP-14. The plasminogen activation system was also altered in tumors with a decrease of urokinase-type plasminogen activator (u-PA) and tissue-type plasminogen activator (t-PA) and a strong increase of plasminogen activator inhibitor-1 (PAI-1). Collectively, our results demonstrate that tumstatin or its C-terminal antitumor fragment, Tum 183-232, inhibits in vivo melanoma progression by triggering an intracellular transduction pathway, which involves a cyclic AMP (cAMP)-dependent mechanism

  13. Tobacco, alcohol, and p53 overexpression in early colorectal neoplasia

    International Nuclear Information System (INIS)

    Terry, Mary Beth; Neugut, Alfred I; Mansukhani, Mahesh; Waye, Jerome; Harpaz, Noam; Hibshoosh, Hanina

    2003-01-01

    The p53 tumor suppressor gene is commonly mutated in colorectal cancer. While the effect of p53 mutations on colorectal cancer prognosis has been heavily studied, less is known about how epidemiologic risk factors relate to p53 status, particularly in early colorectal neoplasia prior to clinically invasive colorectal cancer (including adenomas, carcinoma in situ (CIS), and intramucosal carcinoma). We examined p53 status, as measured by protein overexpression, in 157 cases with early colorectal neoplasia selected from three New York City colonoscopy clinics. After collecting paraffin-embedded tissue blocks, immunohistochemistry was performed using an anti-p53 monoclonal mouse IgG 2 a [BP53-12-1] antibody. We analyzed whether p53 status was different for risk factors for colorectal neoplasia relative to a polyp-free control group (n = 508). p53 overexpression was found in 10.3%, 21.7%, and 34.9%, of adenomatous polyps, CIS, and intramucosal cases, respectively. Over 90% of the tumors with p53 overexpression were located in the distal colon and rectum. Heavy cigarette smoking (30+ years) was associated with cases not overexpressing p53 (OR = 1.8, 95% CI = 1.1–2.9) but not with those cases overexpressing p53 (OR = 1.0, 95% CI = 0.4–2.6). Heavy beer consumption (8+ bottles per week) was associated with cases overexpressing p53 (OR = 4.0, 95% CI = 1.3–12.0) but not with cases without p53 overexpression (OR = 1.6, 95% CI = 0.7–3.7). Our findings that p53 overexpression in early colorectal neoplasia may be positively associated with alcohol intake and inversely associated with cigarette smoking are consistent with those of several studies of p53 expression and invasive cancer, and suggest that there may be relationships of smoking and alcohol with p53 early in the adenoma to carcinoma sequence

  14. Prognostic implication of aquaporin 1 overexpression in resected lung adenocarcinoma.

    Science.gov (United States)

    Bellezza, Guido; Vannucci, Jacopo; Bianconi, Fortunato; Metro, Giulio; Del Sordo, Rachele; Andolfi, Marco; Ferri, Ivana; Siccu, Paola; Ludovini, Vienna; Puma, Francesco; Sidoni, Angelo; Cagini, Lucio

    2017-12-01

    Aquaporins (AQPs) are a group of transmembrane water-selective channel proteins thought to play a role in the regulation of water permeability for plasma membranes. Indeed, high AQP levels have been suggested to promote the progression, invasion and metastasis of tumours. Specifically, AQP1 and AQP5 overexpression in lung adenocarcinoma (AC) have been suggested to be involved in molecular mechanisms in lung cancer. The aim of this retrospective cohort single-centre study was to assess both the levels of expression and therein the prognostic significance, regarding outcome of AQP1 and AQP5 in resected AC patients. Patients with histological diagnoses of lung AC submitted to pulmonary resection were included in this cohort study. Tissue microarrays containing cores from 185 ACs were prepared. AQP1 and AQP5 expressions were assessed by immunohistochemistry. Results were scored as either low (Score 0-2) or high (Score 3-9). Clinical data, pathological tumour-node-metastasis staging and follow-up were recorded. Multivariate Cox survival analysis and Fisher's t-test were performed. AQP1 overexpression was detected in 85 (46%) patients, while AQP5 overexpression was observed in 45 (24%) patients. AQP1 did not result being significantly correlated with clinical and pathological parameters, while AQP5 resulted more expressed in AC with mucinous and papillary predominant patterns. Patients with AQP1 overexpression had shorter disease-free survival (P = 0.001) compared with patients without AQP1 overexpression. Multivariate analysis confirmed that AQP1 overexpression was significantly associated with shorter disease-free survival (P = 0.001). Our results evidenced that AQP1 overexpression resulted in a shorter disease-free survival in lung AC patients. Being so, AQP1 overexpression might be an important prognostic marker in lung AC. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights

  15. Heat-Shock Protein 70 Overexpression in Adipose-Derived Stem Cells Enhances Fat Graft Survival.

    Science.gov (United States)

    Feng, Hao; Qiu, Lihong; Zhang, Teng; Yu, Houyou; Ma, Xianjie; Su, Yingjun; Zheng, Hui; Wang, Yong; Yi, Chenggang

    2017-04-01

    Autologous fat grafting is a prevalent technique used for soft-tissue augmentation; however, the poor survival rate of the grafted tissue remains a drawback of this method. Although adipose-derived stem cells (ASCs) are an attractive candidate for enhancing graft retention, the poor posttransplantation viability of these cells limits their application. Here we investigated whether overexpression of the antiapoptotic protein heat-shock protein 70 (Hsp70) could enhance ASCs' therapeutic potential for fat transplant survival. Recombinant adenoviral vectors were used to overexpress Hsp70 in ASCs isolated from a healthy woman. The Hsp70 expression was assessed by quantitative real-time polymerase chain reaction and Western blot analyses. The adipose tissue granules aspirated from another woman were mixed with ASCs expressing green fluorescent protein (GFP)-tagged Hsp70 (group A) or GFP alone (group B), untreated ASCs (group C), and phosphate-buffered saline (group D). Fat mixtures were then injected subcutaneously into the backs of nude mice, and graft survival was compared after 3 months. Adipose-derived stem cells transduced with recombinant adenoviral vectors exhibited significantly increased Hsp70 expression in vitro. Meanwhile, weight retention analyses demonstrated that fat grafts using the group A cell population exhibited significantly higher survival rates than the other treatment groups in vivo. Moreover, histological analyses revealed that fat grafts containing GFP-Hsp70-expressing ASCs yielded significantly lower levels of tissue fibrosis and fat cysts/vacuoles, higher capillary densities, and increased numbers of viable adipocytes than the control groups. Our data indicate that Hsp70 overexpression enhances the efficacy of ASC therapy by improving the survival and quality of the transplanted fat tissues.

  16. Overexpression of the LH receptor increases distant metastases in an endometrial cancer mouse model

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    Serena ePillozzi

    2013-11-01

    Full Text Available Objective. The aim of the present study was to define the role of luteinizing hormone receptor (LH-R expression in endometrial cancer (EC, using preclinical mouse models, to further transfer these data to the clinical setting. Methods. The role of LH-R over-expression was studied using EC cells (Hec1A, e.g. cells with low endogenous LH-R expression transfected with the LH-R (Hec1A-LH-R. In vitro cell proliferation was measured through the WST1 assay, whereas cell invasion was measured trough the matrigel assay. The effects of LH/hCG-R overexpresion in vivo were analyzed in an appropriately developed preclinical mouse model of EC, which mimicked postmenopausal conditions. The model consisted in an orthotopic xenograft of Hec1A cells into immunodeficient mice treated daily with recombinant LH, to assure high levels of LH. Results. In vitro data indicated that LH-R overexpression increased Hec1A invasiveness. In vivo results showed that tumors arising from Hec1A-LH-R cells injection displayed a higher local invasion and a higher number of distant metastases, mainly in the lung, compared to tumors obtained from the injection of Hec1A cells. LH withdrawl strongly inhibited local and distant metastatic spread of tumors, especially those arising from Hec1A-LH-R cells. Conclusions. The overexpression of the LH-R increases the ability of EC cells to undergo local invasion and metastatic spread. This occurs in the presence of high LH serum concentrations.

  17. Overexpression of Enterococcus faecalis elr operon protects from phagocytosis.

    Science.gov (United States)

    Cortes-Perez, Naima G; Dumoulin, Romain; Gaubert, Stéphane; Lacoux, Caroline; Bugli, Francesca; Martin, Rebeca; Chat, Sophie; Piquand, Kevin; Meylheuc, Thierry; Langella, Philippe; Sanguinetti, Maurizio; Posteraro, Brunella; Rigottier-Gois, Lionel; Serror, Pascale

    2015-05-25

    Mechanisms underlying the transition from commensalism to virulence in Enterococcus faecalis are not fully understood. We previously identified the enterococcal leucine-rich protein A (ElrA) as a virulence factor of E. faecalis. The elrA gene is part of an operon that comprises four other ORFs encoding putative surface proteins of unknown function. In this work, we compared the susceptibility to phagocytosis of three E. faecalis strains, including a wild-type (WT), a ΔelrA strain, and a strain overexpressing the whole elr operon in order to understand the role of this operon in E. faecalis virulence. While both WT and ΔelrA strains were efficiently phagocytized by RAW 264.7 mouse macrophages, the elr operon-overexpressing strain showed a decreased capability to be internalized by the phagocytic cells. Consistently, the strain overexpressing elr operon was less adherent to macrophages than the WT strain, suggesting that overexpression of the elr operon could confer E. faecalis with additional anti-adhesion properties. In addition, increased virulence of the elr operon-overexpressing strain was shown in a mouse peritonitis model. Altogether, our results indicate that overexpression of the elr operon facilitates the E. faecalis escape from host immune defenses.

  18. Overexpression of thrombospondin-1 reduces growth and vascular index but not perfusion in glioblastoma

    DEFF Research Database (Denmark)

    Kragh, Michael; Quistorff, Bjørn; Tenan, Mirna

    2002-01-01

    growth, vascularity, and perfusion. Persistence of TSP-1 overexpression was confirmed after three serial s.c. passages of small xenografted tumor blocks of cells stably transfected with TSP-1 cDNA (clones C9 and E7) or vector controls (pooled clones A7-A9) in immunodeficient nu/nu mice. The tumor...... growth. In size-matched tumors (approximately 300 mm(3)), the blood volume and the histological vessel scores were lower in the TSP-1-transfected tumors than in controls, and this effect was more pronounced in tumors derived from the clone with the highest TSP-1 expression (clone E9). Despite this clear...... and a reduced vascular index at sacrifice are observed in TSP-1-transfected tumors, this did not affect perfusion when size-matched comparisons were performed. Given the increased time needed to reach equal size, it indicates that a fixed rate of perfusion must be maintained in the tumor to allow for growth...

  19. Targeted Overexpression of Inducible 6-Phosphofructo-2-kinase in Adipose Tissue Increases Fat Deposition but Protects against Diet-induced Insulin Resistance and Inflammatory Responses*

    Science.gov (United States)

    Huo, Yuqing; Guo, Xin; Li, Honggui; Xu, Hang; Halim, Vera; Zhang, Weiyu; Wang, Huan; Fan, Yang-Yi; Ong, Kuok Teong; Woo, Shih-Lung; Chapkin, Robert S.; Mashek, Douglas G.; Chen, Yanming; Dong, Hui; Lu, Fuer; Wei, Lai; Wu, Chaodong

    2012-01-01

    Increasing evidence demonstrates the dissociation of fat deposition, the inflammatory response, and insulin resistance in the development of obesity-related metabolic diseases. As a regulatory enzyme of glycolysis, inducible 6-phosphofructo-2-kinase (iPFK2, encoded by PFKFB3) protects against diet-induced adipose tissue inflammatory response and systemic insulin resistance independently of adiposity. Using aP2-PFKFB3 transgenic (Tg) mice, we explored the ability of targeted adipocyte PFKFB3/iPFK2 overexpression to modulate diet-induced inflammatory responses and insulin resistance arising from fat deposition in both adipose and liver tissues. Compared with wild-type littermates (controls) on a high fat diet (HFD), Tg mice exhibited increased adiposity, decreased adipose inflammatory response, and improved insulin sensitivity. In a parallel pattern, HFD-fed Tg mice showed increased hepatic steatosis, decreased liver inflammatory response, and improved liver insulin sensitivity compared with controls. In both adipose and liver tissues, increased fat deposition was associated with lipid profile alterations characterized by an increase in palmitoleate. Additionally, plasma lipid profiles also displayed an increase in palmitoleate in HFD-Tg mice compared with controls. In cultured 3T3-L1 adipocytes, overexpression of PFKFB3/iPFK2 recapitulated metabolic and inflammatory changes observed in adipose tissue of Tg mice. Upon treatment with conditioned medium from iPFK2-overexpressing adipocytes, mouse primary hepatocytes displayed metabolic and inflammatory responses that were similar to those observed in livers of Tg mice. Together, these data demonstrate a unique role for PFKFB3/iPFK2 in adipocytes with regard to diet-induced inflammatory responses in both adipose and liver tissues. PMID:22556414

  20. Select overexpression of homer1a in dorsal hippocampus impairs spatial working memory

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    Tansu Celikel

    2007-10-01

    Full Text Available Long Homer proteins forge assemblies of signaling components involved in glutamate receptor signaling in postsynaptic excitatory neurons, including those underlying synaptic transmission and plasticity. The short immediate-early gene (IEG Homer1a can dynamically uncouple these physical associations by functional competition with long Homer isoforms. To examine the consequences of Homer1amediated uncoupling for synaptic plasticity and behavior, we generated forebrain-specific tetracycline (tet controlled expression of Venus-tagged Homer1a (H1aV in mice. We report that sustained overexpression of H1aV impaired spatial working but not reference memory. Most notably, a similar impairment was observed when H1aV expression was restricted to the dorsal hippocampus (HP, which identifies this structure as the principal cortical area for spatial working memory. Interestingly, H1aV overexpression also abolished maintenance of CA3-CA1 long-term potentiation (LTP. These impairments, generated by sustained high Homer1a levels, identify a requirement for long Homer forms in synaptic plasticity and temporal encoding of spatial memory.

  1. MEK5 overexpression is associated with the occurrence and development of colorectal cancer

    International Nuclear Information System (INIS)

    Diao, Dechang; Wang, Lei; Wan, Jin; Chen, Zhiqiang; Peng, Junsheng; Liu, Huanliang; Chen, Xinlin; Wang, Wei; Zou, Liaonan

    2016-01-01

    Mitogen/extracellular signal-regulated kinase kinase-5 (MEK5) has been confirmed to play a pivotal role in tumor carcinogenesis and progression. However, few studies have investigated the role of MEK5 in colorectal cancer (CRC). MEK5 expression was determined by immunohistochemistry (IHC) in tissue microarrays (TMAs) containing 2 groups of tissues, and western blotting was used to confirm MEK5 expression in 8 cases of primary CRC tissues and paired normal mucosa. RNA interference was used to verify the biological function of MEK5 gene in the development of CRC. IHC revealed the expression of MEK5 was higher in tumor tissues (38.1 %), compared with adjacent normal tissue (8.3 %). Western blot showed that, MEK5 expression was upregulated in CRC tumor tissues compared with normal tissue. Analysis of clinical pathology parameters indicated MEK5 overexpression was significantly correlated with the depth of invasion, lymph node metastasis, distant metastasis and histological grade. Survival analysis revealed that MEK5 overexpression negatively correlated with cancer-free survival (hazard ratio 1.64, P = 0.017). RNA interference-mediated knockdown of MEK5 in SW480 colon cancer cells decreased their proliferation, division, migration and invasiveness in vitro and slowed down tumors growth in mice engrafted with the cells. MEK5 plays an important role in CRC progression and may be a potential molecular target for the treatment of CRC

  2. Osteoblast-targeted overexpression of TAZ increases bone mass in vivo.

    Directory of Open Access Journals (Sweden)

    Jae-Yeon Yang

    Full Text Available Osteoblasts are derived from mesenchymal progenitors. Differentiation to osteoblasts and adipocytes is reciprocally regulated. Transcriptional coactivator with a PDZ-binding motif (TAZ is a transcriptional coactivator that induces differentiation of mesenchymal cells into osteoblasts while blocking differentiation into adipocytes. To investigate the role of TAZ on bone metabolism in vivo, we generated transgenic mice that overexpress TAZ under the control of the procollagen type 1 promoter (Col1-TAZ. Whole body bone mineral density (BMD of 6- to 19-week-old Col-TAZ mice was 4% to 7% higher than that of their wild-type (WT littermates, whereas no difference was noticed in Col.1-TAZ female mice. Microcomputed tomography analyses of proximal tibiae at 16 weeks of age demonstrated a significant increase in trabecular bone volume (26.7% and trabecular number (26.6% with a reciprocal decrease in trabecular spacing (14.2% in Col1-TAZ mice compared with their WT littermates. In addition, dynamic histomorphometric analysis of the lumbar spine revealed increased mineral apposition rate (42.8% and the serum P1NP level was also significantly increased (53% in Col.1-TAZ mice. When primary calvaria cells were cultured in osteogenic medium, alkaline phosphatase (ALP activity was significantly increased and adipogenesis was significantly suppressed in Col1-TAZ mice compared with their WT littermates. Quantitative real-time polymerase chain reaction analyses showed that expression of collagen type 1, bone sialoprotein, osteocalcin, ALP, osterix, and Runx2 was significantly increased in calvaria cells from Col1-TAZ mice compared to their WT littermates. In vitro, TAZ enhanced Runx2-mediated transcriptional activity while suppressing the peroxisome proliferator-activated receptor gamma signaling pathway. TAZ also enhanced transcriptional activity from 3TP-Lux, which reflects transforming growth factor-beta (TGF-β-mediated signaling. In addition, TAZ enhanced TGF

  3. Overexpression of angiotensin-converting enzyme in myelomonocytic cells enhances the immune response [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Kenneth E. Bernstein

    2016-03-01

    Full Text Available Angiotensin-converting enzyme (ACE converts angiotensin I to the vasoconstrictor angiotensin II and thereby plays an important role in blood pressure control. However, ACE is relatively non-specific in its substrate specificity and cleaves many other peptides. Recent analysis of mice overexpressing ACE in monocytes, macrophages, and other myelomonocytic cells shows that these animals have a marked increase in resistance to experimental melanoma and to infection by Listeria monocytogenes or methicillin-resistant Staphylococcus aureus (MRSA. Several other measures of immune responsiveness, including antibody production, are enhanced in these animals. These studies complement a variety of studies indicating an important role of ACE in the immune response.

  4. Myocyte specific overexpression of myoglobin impairs angiogenesis after hind-limb ischemia.

    Science.gov (United States)

    Hazarika, Surovi; Angelo, Michael; Li, Yongjun; Aldrich, Amy J; Odronic, Shelley I; Yan, Zhen; Stamler, Jonathan S; Annex, Brian H

    2008-12-01

    In preclinical models of peripheral arterial disease the angiogenic response is typically robust, though it can be impaired in conditions such as hypercholesterolemia and diabetes where the endothelium is dysfunctional. Myoglobin (Mb) is expressed exclusively in striated muscle cells. We hypothesized that myocyte specific overexpression of myoglobin attenuates ischemia-induced angiogenesis even in the presence of normal endothelium. Mb overexpressing transgenic (MbTg, n=59) and wild-type (WT, n=56) C57Bl/6 mice underwent unilateral femoral artery ligation/excision. Perfusion recovery was monitored using Laser Doppler. Ischemia-induced changes in muscle were assessed by protein and immunohistochemistry assays. Nitrite/nitrate and protein-bound NO, and vasoreactivity was measured. Vasoreactivity was similar between MbTg and WT. In ischemic muscle, at d14 postligation, MbTg increased VEGF-A, and activated eNOS the same as WT mice but nitrate/nitrite were reduced whereas protein-bound NO was higher. MbTg had attenuated perfusion recovery at d21 (0.37+/-0.03 versus 0.47+/-0.02, P<0.05), d28 (0.40+/-0.03 versus 0.50+/-0.04, P<0.05), greater limb necrosis (65.2% versus 15%, P<0.001), a lower capillary density, and greater apoptosis versus WT. Increased Mb expression in myocytes attenuates angiogenesis after hind-limb ischemia by binding NO and reducing its bioavailability. Myoglobin can modulate the angiogenic response to ischemia even in the setting of normal endothelium.

  5. Overexpression or absence of calretinin in mouse primary mesothelial cells inversely affects proliferation and cell migration.

    Science.gov (United States)

    Blum, Walter; Pecze, László; Felley-Bosco, Emanuela; Schwaller, Beat

    2015-12-22

    The Ca(2+)-binding protein calretinin is currently used as a positive marker for identifying epithelioid malignant mesothelioma (MM) and reactive mesothelium, but calretinin's likely role in mesotheliomagenesis remains unclear. Calretinin protects immortalized mesothelial cells in vitro from asbestos-induced cytotoxicity and thus might be implicated in mesothelioma formation. To further investigate calretinin's putative role in the early steps of MM generation, primary mesothelial cells from calretinin knockout (CR-/-) and wildtype (WT) mice were compared. Primary mouse mesothelial cells from WT and CR-/- mice were investigated with respect to morphology, marker proteins, proliferation, cell cycle parameters and mobility in vitro. Overexpression of calretinin or a nuclear-targeted variant was achieved by a lentiviral expression system. CR-/- mice have a normal mesothelium and no striking morphological abnormalities compared to WT animals were noted. Primary mouse mesothelial cells from both genotypes show a typical "cobblestone-like" morphology and express mesothelial markers including mesothelin. In cells from CR-/- mice in vitro, we observed more giant cells and a significantly decreased proliferation rate. Up-regulation of calretinin in mesothelial cells of both genotypes increases the proliferation rate and induces a cobblestone-like epithelial morphology. The length of the S/G2/M phase is unchanged, however the G1 phase is clearly prolonged in CR-/- cells. They are also much slower to close a scratch in a confluent cell layer (2D-wound assay). In addition to a change in cell morphology, an increase in proliferation and mobility is observed, if calretinin overexpression is targeted to the nucleus. Thus, both calretinin and nuclear-targeted calretinin increase mesothelial cell proliferation and consequently, speed up the scratch-closure time. The increased rate of scratch closure in WT cells is the result of two processes: an increased proliferation rate and

  6. Overexpression of Mineralocorticoid Receptors in the Mouse Forebrain Partly Alleviates the Effects of Chronic Early Life Stress on Spatial Memory, Neurogenesis and Synaptic Function in the Dentate Gyrus

    Directory of Open Access Journals (Sweden)

    Sofia Kanatsou

    2017-05-01

    Full Text Available Evidence from human studies suggests that high expression of brain mineralocorticoid receptors (MR may promote resilience against negative consequences of stress exposure, including childhood trauma. We examined, in mice, whether brain MR overexpression can alleviate the effects of chronic early life stress (ELS on contextual memory formation under low and high stress conditions, and neurogenesis and synaptic function of dentate gyrus granular cells. Male mice were exposed to ELS by housing the dam with limited nesting and bedding material from postnatal day (PND 2 to 9. We investigated the moderating role of MRs by using forebrain-specific transgenic MR overexpression (MR-tg mice. Low-stress contextual (i.e., object relocation memory formation was hampered by ELS in wildtype but not MR-tg mice. Anxiety like behavior and high-stress contextual (i.e., fear memory formation were unaffected by ELS and/or MR expression level. At the cellular level, an interaction effect was observed between ELS and MR overexpression on the number of doublecortin-positive cells, with a significant difference between the wildtype ELS and MR-tg ELS groups. No interaction was found regarding Ki-67 and BrdU staining. A significant interaction between ELS and MR expression was further observed with regard to mEPSCs and mIPSC frequency. The ratio of evoked EPSC/IPSC or NMDA/AMPA responses was unaffected. Overall, these results suggest that ELS affects contextual memory formation under low stress conditions as well as neurogenesis and synaptic transmission in dentate granule cells, an effect that can be alleviated by MR-overexpression.

  7. Zinc-finger protein 418 overexpression protects against cardiac hypertrophy and fibrosis.

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    Liming Pan

    Full Text Available This study aimed to investigated the effect and mechanism of zinc-finger protein 418 (ZNF418 on cardiac hypertrophy caused by aortic banding (AB, phenylephrine (PE or angiotensin II (Ang II in vivo and in vitro.The expression of ZNF418 in hearts of patients with dilated cardiomyopathy (DCM or hypertrophic cardiomyopathy (HCM and AB-induced cardiac hypertrophy mice, as well as in Ang II- or PE-induced hypertrophic primary cardiomyocytes was detected by western blotting. Then, the expression of ZNF418 was up-regulated or down-regulated in AB-induced cardiac hypertrophy mice and Ang II -induced hypertrophic primary cardiomyocytes. The hypertrophic responses and fibrosis were evaluated by echocardiography and histological analysis. The mRNA levels of hypertrophy markers and fibrotic markers were detected by RT-qPCR. Furthermore, the phosphorylation and total levels of c-Jun were measured by western blotting.ZNF418 was markedly down-regulated in hearts of cardiac hypertrophy and hypertrophic primary cardiomyocytes. Down-regulated ZNF418 exacerbated the myocyte size and fibrosis, moreover increased the mRNA levels of ANP, BNP, β-MHC, MCIP1.4, collagen 1a, collagen III, MMP-2 and fibronection in hearts of AB-treated ZNF418 knockout mice or Ang II-treated cardiomyocytes with AdshZNF418. Conversely, these hypertrophic responses were reduced in the ZNF418 transgenic (TG mice treated by AB and the AdZNF418-transfected primary cardiomyocytes treated by Ang II. Additionally, the deficiency of ZNF418 enhanced the phosphorylation level of c-jun, and overexpression of ZNF418 suppressed the phosphorylation level of c-jun in vivo and in vitro.ZNF418 maybe attenuate hypertrophic responses by inhibiting the activity of c-jun/AP-1.

  8. Zinc-finger protein 418 overexpression protects against cardiac hypertrophy and fibrosis

    Science.gov (United States)

    Huang, Zirui; Zhu, Zhilin; Xu, Chunli; Teng, Lin; He, Ling; Gu, Chen; Yi, Cai

    2017-01-01

    Background This study aimed to investigated the effect and mechanism of zinc-finger protein 418 (ZNF418) on cardiac hypertrophy caused by aortic banding (AB), phenylephrine (PE) or angiotensin II (Ang II) in vivo and in vitro. Methods The expression of ZNF418 in hearts of patients with dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM) and AB-induced cardiac hypertrophy mice, as well as in Ang II- or PE-induced hypertrophic primary cardiomyocytes was detected by western blotting. Then, the expression of ZNF418 was up-regulated or down-regulated in AB-induced cardiac hypertrophy mice and Ang II -induced hypertrophic primary cardiomyocytes. The hypertrophic responses and fibrosis were evaluated by echocardiography and histological analysis. The mRNA levels of hypertrophy markers and fibrotic markers were detected by RT-qPCR. Furthermore, the phosphorylation and total levels of c-Jun were measured by western blotting. Results ZNF418 was markedly down-regulated in hearts of cardiac hypertrophy and hypertrophic primary cardiomyocytes. Down-regulated ZNF418 exacerbated the myocyte size and fibrosis, moreover increased the mRNA levels of ANP, BNP, β-MHC, MCIP1.4, collagen 1a, collagen III, MMP-2 and fibronection in hearts of AB-treated ZNF418 knockout mice or Ang II-treated cardiomyocytes with AdshZNF418. Conversely, these hypertrophic responses were reduced in the ZNF418 transgenic (TG) mice treated by AB and the AdZNF418-transfected primary cardiomyocytes treated by Ang II. Additionally, the deficiency of ZNF418 enhanced the phosphorylation level of c-jun, and overexpression of ZNF418 suppressed the phosphorylation level of c-jun in vivo and in vitro. Conclusion ZNF418 maybe attenuate hypertrophic responses by inhibiting the activity of c-jun/AP-1. PMID:29065170

  9. Cloning Mice.

    Science.gov (United States)

    Ogura, Atsuo

    2017-08-01

    Viable and fertile mice can be generated by somatic nuclear transfer into enucleated oocytes, presumably because the transplanted somatic cell genome becomes reprogrammed by factors in the oocyte. The first somatic cloned offspring of mice were obtained by directly injecting donor nuclei into recipient enucleated oocytes. When this method is used (the so-called Honolulu method of somatic cell nuclear transfer [SCNT]), the donor nuclei readily and completely condense within the enucleated metaphase II-arrested oocytes, which contain high levels of M-phase-promoting factor (MPF). It is believed that the condensation of the donor chromosomes promotes complete reprogramming of the donor genome within the mouse oocytes. Another key to the success of mouse cloning is the use of blunt micropipettes attached to a piezo impact-driving micromanipulation device. This system saves a significant amount of time during the micromanipulation of oocytes and thus minimizes the loss of oocyte viability in vitro. For example, a group of 20 oocytes can be enucleated within 10 min by an experienced operator. This protocol is composed of seven parts: (1) preparing micropipettes, (2) setting up the enucleation and injection micropipettes, (3) collecting and enucleating oocytes, (4) preparing nucleus donor cells, (5) injecting donor nuclei, (6) activating embryos and culturing, and (7) transferring cloned embryos. © 2017 Cold Spring Harbor Laboratory Press.

  10. Consequences of membrane protein overexpression in Escherichia coli.

    Science.gov (United States)

    Wagner, Samuel; Baars, Louise; Ytterberg, A Jimmy; Klussmeier, Anja; Wagner, Claudia S; Nord, Olof; Nygren, Per-Ake; van Wijk, Klaas J; de Gier, Jan-Willem

    2007-09-01

    Overexpression of membrane proteins is often essential for structural and functional studies, but yields are frequently too low. An understanding of the physiological response to overexpression is needed to improve such yields. Therefore, we analyzed the consequences of overexpression of three different membrane proteins (YidC, YedZ, and LepI) fused to green fluorescent protein (GFP) in the bacterium Escherichia coli and compared this with overexpression of a soluble protein, GST-GFP. Proteomes of total lysates, purified aggregates, and cytoplasmic membranes were analyzed by one- and two-dimensional gel electrophoresis and mass spectrometry complemented with flow cytometry, microscopy, Western blotting, and pulse labeling experiments. Composition and accumulation levels of protein complexes in the cytoplasmic membrane were analyzed with improved two-dimensional blue native PAGE. Overexpression of the three membrane proteins, but not soluble GST-GFP, resulted in accumulation of cytoplasmic aggregates containing the overexpressed proteins, chaperones (DnaK/J and GroEL/S), and soluble proteases (HslUV and ClpXP) as well as many precursors of periplasmic and outer membrane proteins. This was consistent with lowered accumulation levels of secreted proteins in the three membrane protein overexpressors and is likely to be a direct consequence of saturation of the cytoplasmic membrane protein translocation machinery. Importantly accumulation levels of respiratory chain complexes in the cytoplasmic membrane were strongly reduced. Induction of the acetate-phosphotransacetylase pathway for ATP production and a down-regulated tricarboxylic acid cycle indicated the activation of the Arc two-component system, which mediates adaptive responses to changing respiratory states. This study provides a basis for designing rational strategies to improve yields of membrane protein overexpression in E. coli.

  11. HER2 amplification, overexpression and score criteria in esophageal adenocarcinoma

    Science.gov (United States)

    Hu, Yingchuan; Bandla, Santhoshi; Godfrey, Tony E.; Tan, Dongfeng; Luketich, James D.; Pennathur, Arjun; Qiu, Xing; Hicks, David G.; Peters, Jeffrey; Zhou, Zhongren

    2011-01-01

    The HER2 oncogene was recently reported to be amplified and overexpressed in esophageal adenocarcinoma. However, the relationship of HER2 amplification in esophageal adenocarcinoma with prognosis has not been well defined. The scoring systems for clinically evaluating HER2 in esophageal adenocarcinoma are not established. The aims of the study were to establish a HER2 scoring system and comprehensively investigate HER2 amplification and overexpression in esophageal adenocarcinoma and its precursor lesion. Using a tissue microarray, containing 116 cases of esophageal adenocarcinoma, 34 cases of BE, 18 cases of low grade dysplasia and 15 cases of high grade dysplasia, HER2 amplification and overexpression were analyzed by HercepTest and CISH methods. The amplification frequency in an independent series of 116 esophageal adenocarcinoma samples was also analyzed using Affymetrix SNP 6.0 microarrays. In our studies, we have found that HER2 amplification does not associate with poor prognosis in total 232 esophageal adenocarcinoma patients by CISH and high density microarrays. We further confirm the similar frequency of HER2 amplification by CISH (18.10%; 21/116) and SNP 6.0 microarrays (16.4%, 19/116) in esophageal adenocarcinoma. HER2 protein overexpression was observed in 12.1 % (14/116) of esophageal adenocarcinoma and 6.67% (1/15) of HGD. No HER2 amplification or overexpression was identified in BE or LGD. All HER2 protein overexpression cases showed HER2 gene amplification. Gene amplification was found to be more frequent by CISH than protein overexpression in esophageal adenocarcinoma (18.10% vs 12.9%). A modified two-step model for esophageal adenocarcinoma HER-2 testing is recommend for clinical esophageal adenocarcinoma HER-2 trial. PMID:21460800

  12. Induction of basal cell carcinomas and trichoepitheliomas in mice overexpressing GLI-1

    OpenAIRE

    Nilsson, Mats; Undèn, Anne Birgitte; Krause, Darren; Malmqwist, Ulrica; Raza, Karima; Zaphiropoulos, Peter G.; Toftgård, Rune

    2000-01-01

    Basal cell carcinoma is the most prevalent cancer in the western world, showing a rapid increase in incidence. Activation of the Sonic hedgehog/Patched (PTCH) signaling pathway because of PTCH1 inactivation is a key event in sporadic and familial basal cell carcinoma development in humans and is associated with transcriptional activation of specific target genes, including PTCH1 itself. These changes are analogous to the situation in Drosophila where hedgehog activates the zinc-finger transcr...

  13. Alterations of plasma lipids in mice via adenoviral-mediated hepatic overexpression of human ABCA1

    NARCIS (Netherlands)

    Wellington, Cheryl L.; Brunham, Liam R.; Zhou, Steven; Singaraja, Roshni R.; Visscher, Henk; Gelfer, Allison; Ross, Colin; James, Erick; Liu, Guoqing; Huber, Mary T.; Yang, Yu-Zhou; Parks, Robin J.; Groen, Albert; Fruchart-Najib, Jamila; Hayden, Michael R.

    2003-01-01

    ATP binding cassette transporter A1 (ABCA1) is a widely expressed lipid transporter essential for the generation of HDL. ABCA1 is particularly abundant in the liver, suggesting that the liver may play a major role in HDL homeostasis. To determine how hepatic ABCA1 affects plasma HDL cholesterol

  14. Transgenic mice overexpressing human KvLQT1 dominant-negative isoform. Part I: Phenotypic characterisation

    NARCIS (Netherlands)

    Demolombe, S.; Lande, G.; Charpentier, F.; van Roon, M. A.; van den Hoff, M. J.; Toumaniantz, G.; Baro, I.; Guihard, G.; Le Berre, N.; Corbier, A.; de Bakker, Jacques; Opthof, T.; Wilde, A.; Moorman, A. F.; Escande, D.

    2001-01-01

    OBJECTIVES: The KCNQ1 gene encodes the KvLQT1 potassium channel, which generates in the human heart the slow component of the cardiac delayed rectifier current, I(Ks). Mutations in KCNQ1 are the most frequent cause of the congenital long QT syndrome. We have previously cloned a cardiac KCNQ1 human

  15. Effects of Mineralocorticoid Receptor Overexpression on Anxiety and Memory after Early Life Stress in Female Mice

    NARCIS (Netherlands)

    Kanatsou, Sofia; Ter Horst, Judith P; Harris, Anjanette P; Seckl, Jonathan R; Krugers, Harmen J; Joëls, Marian

    2016-01-01

    Early-life stress (ELS) is a risk factor for the development of psychopathology, particularly in women. Human studies have shown that certain haplotypes of NR3C2, encoding the mineralocorticoid receptor (MR), that result in gain of function, may protect against the consequences of stress exposure,

  16. Transgenic overexpression of Niemann-Pick C2 protein promotes cholesterol gallstone formation in mice

    NARCIS (Netherlands)

    Acuna, Mariana; Gonzalez-Hodar, Lila; Amigo, Ludwig; Castro, Juan; Gabriela Morales, M.; Cancino, Gonzalo I.; Groen, Albert K.; Young, Juan; Francisco Miquel, Juan; Zanlungo, Silvana

    Background & Aims: Niemann-Pick C2 (NPC2) is a lysosomal protein involved in the egress of low-density lipoprotein-derived cholesterol from lysosomes to other intracellular compartments. NPC2 has been detected in several tissues and is also secreted from the liver into bile. We have previously shown

  17. Effects of Mineralocorticoid Receptor Overexpression on Anxiety and Memory after Early Life Stress in Female Mice

    NARCIS (Netherlands)

    Kanatsou, S.; ter Horst, J.P.; Harris, A.P.; Seckl, J.R.; Krugers, H.J.; Joëls, M.

    2015-01-01

    Early-life stress (ELS) is a risk factor for the development of psychopathology, particularly in women. Human studies have shown that certain haplotypes of NR3C2, encoding the mineralocorticoid receptor (MR), that result in gain of function, may protect against the consequences of stress exposure,

  18. Skeletal muscle overexpression of nicotinamide phosphoribosyl transferase in mice coupled with voluntary exercise augments exercise endurance

    Directory of Open Access Journals (Sweden)

    Sheila R. Costford

    2018-01-01

    Conclusions: Our studies have unveiled a fascinating interaction between elevated NAMPT activity in skeletal muscle and voluntary exercise that was manifest as a striking improvement in exercise endurance.

  19. Female-to-male sex reversal in mice caused by transgenic overexpression of Dmrt1.

    Science.gov (United States)

    Zhao, Liang; Svingen, Terje; Ng, Ee Ting; Koopman, Peter

    2015-03-15

    Genes related to Dmrt1, which encodes a DNA-binding DM domain transcription factor, act as triggers for primary sex determination in a broad range of metazoan species. However, this role is fulfilled in mammals by Sry, a newly evolved gene on the Y chromosome, such that Dmrt1 has become dispensable for primary sex determination and instead maintains Sertoli cell phenotype in postnatal testes. Here, we report that enforced expression of Dmrt1 in XX mouse fetal gonads using a Wt1-BAC transgene system is sufficient to drive testicular differentiation and male secondary sex development. XX transgenic fetal gonads showed typical testicular size and vasculature. Key ovarian markers, including Wnt4 and Foxl2, were repressed. Sertoli cells expressing the hallmark testis-determining gene Sox9 were formed, although they did not assemble into normal testis cords. Other bipotential lineages differentiated into testicular cell types, including steroidogenic fetal Leydig cells and non-meiotic germ cells. As a consequence, male internal and external reproductive organs developed postnatally, with an absence of female reproductive tissues. These results reveal that Dmrt1 has retained its ability to act as the primary testis-determining trigger in mammals, even though this function is no longer normally required. Thus, Dmrt1 provides a common thread in the evolution of sex determination mechanisms in metazoans. © 2015. Published by The Company of Biologists Ltd.

  20. Female-to-male sex reversal in mice caused by transgenic overexpression of Dmrt1

    DEFF Research Database (Denmark)

    Zhao, Liang; Svingen, Terje; Ting Ng, Ee

    2015-01-01

    Genes related to Dmrt1, which encodes a DNA-binding DM domain transcription factor, act as triggers for primary sex determination in a broad range of metazoan species. However, this role is fulfilled in mammals by Sry, a newly evolved gene on the Y chromosome, such that Dmrt1 has become dispensab...

  1. Arsenic treatment increase Aurora-A overexpression through E2F1 activation in bladder cells.

    Science.gov (United States)

    Kao, Yu-Ting; Wu, Chin-Han; Wu, Shan-Ying; Lan, Sheng-Hui; Liu, Hsiao-Sheng; Tseng, Ya-Shih

    2017-04-18

    Arsenic is a widely distributed metalloid compound that has biphasic effects on cultured cells. In large doses, arsenic can be toxic enough to trigger cell death. In smaller amounts, non-toxic doses may promote cell proliferation and induces carcinogenesis. Aberration of chromosome is frequently detected in epithelial cells and lymphocytes of individuals from arsenic contaminated areas. Overexpression of Aurora-A, a mitotic kinase, results in chromosomal instability and cell transformation. We have reported that low concentration (≦1 μM) of arsenic treatment increases Aurora-A expression in immortalized bladder urothelial E7 cells. However, how arsenic induces carcinogenesis through Aurora-A activation remaining unclear. Bromodeoxyuridine (BrdU) staining, MTT assay, and flow cytometry assay were conducted to determine cell proliferation. Messenger RNA and protein expression levels of Aurora-A were detected by reverse transcriptional-PCR and Western blotting, respectively. Centrosome of cells was observed by immunofluorescent staining. The transcription factor of Aurora-A was investigated by promoter activity, chromosome immunoprecipitation (ChIP), and small interfering RNA (shRNA) assays. Mouse model was utilized to confirm the relationship between arsenic and Aurora-A. We reveal that low dosage of arsenic treatment increased cell proliferation is associated with accumulated cell population at S phase. We also detected increased Aurora-A expression at mRNA and protein levels in immortalized bladder urothelial E7 cells exposed to low doses of arsenic. Arsenic-treated cells displayed increased multiple centrosome which is resulted from overexpressed Aurora-A. Furthermore, the transcription factor, E2F1, is responsible for Aurora-A overexpression after arsenic treatment. We further disclosed that Aurora-A expression and cell proliferation were increased in bladder and uterus tissues of the BALB/c mice after long-term arsenic (1 mg/L) exposure for 2 months. We

  2. Conditional TNF-α Overexpression in the Tooth and Alveolar Bone Results in Painful Pulpitis and Osteitis.

    Science.gov (United States)

    Hall, B E; Zhang, L; Sun, Z J; Utreras, E; Prochazkova, M; Cho, A; Terse, A; Arany, P; Dolan, J C; Schmidt, B L; Kulkarni, A B

    2016-02-01

    Tumor necrosis factor-α (TNF-α) is a proalgesic cytokine that is commonly expressed following tissue injury. TNF-α expression not only promotes inflammation but can also lead to pain hypersensitivity in nociceptors. With the established link between TNF-α and inflammatory pain, we identified its increased expression in the teeth of patients affected with caries and pulpitis. We generated a transgenic mouse model (TNF-α(glo)) that could be used to conditionally overexpress TNF-α. These mice were bred with a dentin matrix protein 1 (DMP1)-Cre line for overexpression of TNF-α in both the tooth pulp and bone to study oral pain that would result from subsequent development of pulpitis and bone loss. The resulting DMP1/TNF-α(glo) mice show inflammation in the tooth pulp that resembles pulpitis while also displaying periodontal bone loss. Inflammatory infiltrates and enlarged blood vessels were observed in the tooth pulp. Pulpitis and osteitis affected the nociceptive neurons innervating the orofacial region by causing increased expression of inflammatory cytokines within the trigeminal ganglia. With this new mouse model morphologically mimicking pulpitis and osteitis, we tested it for signs of oral pain with an oral function assay (dolognawmeter). This assay/device records the time required by a mouse to complete a discrete gnawing task. The duration of gnawing required by the DMP1/TNF-α(glo) mice to complete the task was greater than that for the controls; extended gnaw time in a dolognawmeter indicates reduced orofacial function. With the DMP1/TNF-α(glo) mice, we have shown that TNF-α expression alone can produce inflammation similar to pulpitis and osteitis and that this mouse model can be used to study dental inflammatory pain. © International & American Associations for Dental Research 2015.

  3. Hypothalamic over-expression of VGF in the Siberian hamster increases energy expenditure and reduces body weight gain.

    Science.gov (United States)

    Lewis, Jo E; Brameld, John M; Hill, Phil; Cocco, Cristina; Noli, Barbara; Ferri, Gian-Luca; Barrett, Perry; Ebling, Francis J P; Jethwa, Preeti H

    2017-01-01

    VGF (non-acronymic) was first highlighted to have a role in energy homeostasis through experiments involving dietary manipulation in mice. Fasting increased VGF mRNA in the Arc and levels were subsequently reduced upon refeeding. This anabolic role for VGF was supported by observations in a VGF null (VGF-/-) mouse and in the diet-induced and gold-thioglucose obese mice. However, this anabolic role for VGF has not been supported by a number of subsequent studies investigating the physiological effects of VGF-derived peptides. Intracerebroventricular (ICV) infusion of TLQP-21 increased resting energy expenditure and rectal temperature in mice and protected against diet-induced obesity. Similarly, ICV infusion of TLQP-21 into Siberian hamsters significantly reduced body weight, but this was due to a decrease in food intake, with no effect on energy expenditure. Subsequently NERP-2 was shown to increase food intake in rats via the orexin system, suggesting opposing roles for these VGF-derived peptides. Thus to further elucidate the role of hypothalamic VGF in the regulation of energy homeostasis we utilised a recombinant adeno-associated viral vector to over-express VGF in adult male Siberian hamsters, thus avoiding any developmental effects or associated functional compensation. Initially, hypothalamic over-expression of VGF in adult Siberian hamsters produced no effect on metabolic parameters, but by 12 weeks post-infusion hamsters had increased oxygen consumption and a tendency to increased carbon dioxide production; this attenuated body weight gain, reduced interscapular white adipose tissue and resulted in a compensatory increase in food intake. These observed changes in energy expenditure and food intake were associated with an increase in the hypothalamic contents of the VGF-derived peptides AQEE, TLQP and NERP-2. The complex phenotype of the VGF-/- mice is a likely consequence of global ablation of the gene and its derived peptides during development, as well

  4. Overexpression of microRNA-26a protects against deficient β-cell function via targeting phosphatase with tensin homology in mouse models of type 2 diabetes.

    Science.gov (United States)

    Song, Yingli; Jin, Di; Jiang, Xiaoshu; Lv, Chunmei; Zhu, Hui

    2018-01-01

    The prevalence of type 2 diabetes mellitus (T2DM) increased rapidly in the world. The development of β-cell dysfunction is the quintessential defects in T2DM patients However, the pathogenesis of β-cell dysfunction is still unclear. MicroRNAs are short non-coding RNAs and has been reported to be involved in pathogenesis of β-cell dysfunction and T2DM. Here, we investigated the mechanisms by which miR-26a regulate β-cell function and insulin signaling pathway in high fat diet (HFD) fed and db/db T2DM mice model. The expression of miR-26a was down-regulated dramatically in the serum and islets of both HFD and db/db mice model. miR-26a overexpression protected against HFD-induced diabetes and maintained prolonged normoglycemic time in HFD fed mice. Overexpression of miR-26a improved β-cell dysfunction in T2DM mice. Further, we identified that PTEN is a direct target gene of miR-26a. Overexpression of miR-26a significantly inhibited the luciferase activity of hPTEN 3'-UTR, while the effect of miR-26a disappeared when the miR-26a potential binding site within the PTEN 3'-UTR was mutated. Overexpression of miR-26a reduced both the mRNA and protein levels of PTEN in vitro and in vivo. We also found that miR-26a overexpression increased the expression of p-Akt and p-FoxO-1, while the effect of miR-26a was blocked by PTEN overexpression. In conclusion, our data indicated that miR-26a potentially contributes to the β-cell dysfunction in T2DM, and miR-26a may be a new therapeutic strategy against T2DM. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Human neural stem cells over-expressing VEGF provide neuroprotection, angiogenesis and functional recovery in mouse stroke model.

    Directory of Open Access Journals (Sweden)

    Hong J Lee

    Full Text Available BACKGROUND: Intracerebral hemorrhage (ICH is a lethal stroke type. As mortality approaches 50%, and current medical therapy against ICH shows only limited effectiveness, an alternative approach is required, such as stem cell-based cell therapy. Previously we have shown that intravenously transplanted human neural stem cells (NSCs selectively migrate to the brain and induce behavioral recovery in rat ICH model, and that combined administration of NSCs and vascular endothelial growth factor (VEGF results in improved structural and functional outcome from cerebral ischemia. METHODS AND FINDINGS: We postulated that human NSCs overexpressing VEGF transplanted into cerebral cortex overlying ICH lesion could provide improved survival of grafted NSCs, increased angiogenesis and behavioral recovery in mouse ICH model. ICH was induced in adult mice by unilateral injection of bacterial collagenase into striatum. HB1.F3.VEGF human NSC line produced an amount of VEGF four times higher than parental F3 cell line in vitro, and induced behavioral improvement and 2-3 fold increase in cell survival at two weeks and eight weeks post-transplantation. CONCLUSIONS: Brain transplantation of F3 human NSCs over-expressing VEGF near ICH lesion sites provided differentiation and survival of grafted human NSCs and renewed angiogenesis of host brain and functional recovery of ICH animals. These results suggest a possible application of the human neural stem cell line, which is genetically modified to over-express VEGF, as a therapeutic agent for ICH-stroke.

  6. SOD1 Overexpression Preserves Baroreflex Control of Heart Rate with an Increase of Aortic Depressor Nerve Function

    Science.gov (United States)

    Hatcher, Jeffrey; Gu, He; Cheng, Zixi (Jack)

    2016-01-01

    Overproduction of reactive oxygen species (ROS), such as the superoxide radical (O2 ∙−), is associated with diseases which compromise cardiac autonomic function. Overexpression of SOD1 may offer protection against ROS damage to the cardiac autonomic nervous system, but reductions of O2 ∙− may interfere with normal cellular functions. We have selected the C57B6SJL-Tg (SOD1)2 Gur/J mouse as a model to determine whether SOD1 overexpression alters cardiac autonomic function, as measured by baroreflex sensitivity (BRS) and aortic depressor nerve (ADN) recordings, as well as evaluation of baseline heart rate (HR) and mean arterial pressure (MAP). Under isoflurane anesthesia, C57 wild-type and SOD1 mice were catheterized with an arterial pressure transducer and measurements of HR and MAP were taken. After establishing a baseline, hypotension and hypertension were induced by injection of sodium nitroprusside (SNP) and phenylephrine (PE), respectively, and ΔHR versus ΔMAP were recorded as a measure of baroreflex sensitivity (BRS). SNP and PE treatment were administered sequentially after a recovery period to measure arterial baroreceptor activation by recording aortic depressor nerve activity. Our findings show that overexpression of SOD1 in C57B6SJL-Tg (SOD1)2 Gur/J mouse preserved the normal HR, MAP, and BRS but enhanced aortic depressor nerve function. PMID:26823951

  7. Role of paraoxonase-1 in bone anabolic effects of parathyroid hormone in hyperlipidemic mice

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jinxiu [Department of Physiology, University of California, Los Angeles (United States); Cheng, Henry [Department of Medicine, University of California, Los Angeles (United States); Atti, Elisa [Division of Diagnostic and Surgical Sciences, School of Dentistry, University of California, Los Angeles (United States); Shih, Diana M. [Department of Medicine, University of California, Los Angeles (United States); Demer, Linda L. [Department of Physiology, University of California, Los Angeles (United States); Department of Medicine, University of California, Los Angeles (United States); Department of Bioengineering, University of California, Los Angeles (United States); Tintut, Yin, E-mail: ytintut@mednet.ucla.edu [Department of Medicine, University of California, Los Angeles (United States)

    2013-02-01

    Highlights: ► Anabolic effects of PTH were tested in hyperlipidemic mice overexpressing PON1. ► Expression of antioxidant regulatory genes was induced in PON1 overexpression. ► Bone resorptive activity was reduced in PON1 overexpressing hyperlipidemic mice. ► PON1 restored responsiveness to intermittent PTH in bones of hyperlipidemic mice. -- Abstract: Hyperlipidemia blunts anabolic effects of intermittent parathyroid hormone (PTH) on cortical bone, and the responsiveness to PTH are restored in part by oral administration of the antioxidant ApoA-I mimetic peptide, D-4F. To evaluate the mechanism of this rescue, hyperlipidemic mice overexpressing the high-density lipoprotein-associated antioxidant enzyme, paraoxonase 1 (Ldlr{sup −/−}PON1{sup tg}) were generated, and daily PTH injections were administered to Ldlr{sup −/−}PON1{sup tg} and to littermate Ldlr{sup −/−} mice. Expression of bone regulatory genes was determined by realtime RT-qPCR, and cortical bone parameters of the femoral bones by micro-computed tomographic analyses. PTH-treated Ldlr{sup −/−}PON1{sup tg} mice had significantly greater expression of PTH receptor (PTH1R), activating transcription factor-4 (ATF4), and osteoprotegerin (OPG) in femoral cortical bone, as well as significantly greater cortical bone mineral content, thickness, and area in femoral diaphyses compared with untreated Ldlr{sup −/−}PON1{sup tg} mice. In contrast, in control mice (Ldlr{sup −/−}) without PON1 overexpression, PTH treatment did not induce these markers. Calvarial bone of PTH-treated Ldlr{sup −/−}PON1{sup tg} mice also had significantly greater expression of osteoblastic differentiation marker genes as well as BMP-2-target and Wnt-target genes. Untreated Ldlr{sup −/−}PON1{sup tg} mice had significantly greater expression of PTHR1 than untreated Ldlr{sup −/−} mice, whereas sclerostin expression was reduced. In femoral cortical bones, expression levels of transcription factors, Fox

  8. Overexpression of tissue-nonspecific alkaline phosphatase (TNAP) in endothelial cells accelerates coronary artery disease in a mouse model of familial hypercholesterolemia

    Science.gov (United States)

    Romanelli, Filippo; Corbo, AnthonyMarco; Salehi, Maryam; Yadav, Manisha C.; Salman, Soha; Petrosian, David; Rashidbaigi, Omid J.; Chait, Jesse; Kuruvilla, Jes; Plummer, Maria; Radichev, Ilian; Margulies, Kenneth B.; Gerdes, A. Martin; Pinkerton, Anthony B.; Millán, José Luis; Savinov, Alexei Y.

    2017-01-01

    Objective Overexpression of tissue-nonspecific alkaline phosphatase (TNAP) in endothelium leads to arterial calcification in mice. The purpose of this study was to examine the effect of elevated endothelial TNAP on coronary atherosclerosis. In addition, we aimed to examine endogenous TNAP activity in human myocardium. Approach and results A vascular pattern of TNAP activity was observed in human non-failing, ischemic, and idiopathic dilated hearts (5 per group); no differences were noted between groups in this study. Endothelial overexpression of TNAP was achieved in mice harboring a homozygous recessive mutation in the low density lipoprotein receptor (whc allele) utilizing a Tie2-cre recombinase (WHC-eTNAP mice). WHC-eTNAP developed significant coronary artery calcification at baseline compared WHC controls (4312 vs 0μm2 alizarin red area, pcoronary arteries of WHC-eTNAP was increased compared to WHC controls (121633 vs 9330μm2 oil red O area, pCoronary lesions in WHC-eTNAP mice exhibited intimal thickening, calcifications, foam cells, and necrotic cores. This was accompanied by the reduction in body weight and left ventricular ejection fraction (19.5 vs. 23.6g, pcoronary calcium (78838 vs.144622μm2) and lipids (30754 vs. 77317μm2); improved body weight (22.4 vs.18.8g) and ejection fraction (59 vs. 47%). The effects of SBI-425 were significant in the direct comparisons with placebo but disappeared after TNAP-negative placebo-treated group was included in the models as healthy controls. Conclusions Endogenous TNAP activity is present in human cardiac tissues. TNAP overexpression in vascular endothelium in mice leads to an unusual course of coronary atherosclerosis, in which calcification precedes lipid deposition. The prevalence and significance of this mechanism in human atherosclerosis requires further investigations. PMID:29023576

  9. Adeno-associated virus-mediated neuroglobin overexpression ameliorates the N-methyl-N-nitrosourea-induced retinal impairments: a novel therapeutic strategy against photoreceptor degeneration

    Directory of Open Access Journals (Sweden)

    Tao Y

    2017-10-01

    Full Text Available Ye Tao,1,* Zhen Yang,2,* Wei Fang,2 Zhao Ma,3 Yi Fei Huang,1 Zhengwei Li4 1Department of Ophthalmology, Key Lab of Ophthalmology and Visual Science, Chinese PLA General Hospital, Beijing, 2Department of Neurosurgery, Institute for Functional Brain Disorders, Tangdu Hospital, Fourth Military Medical University, Xi’an, 3Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, 4Department of Neurosurgery, Zhongnan Hospital of Wuhan University, Wuhan, People’s Republic of China *These authors contributed equally to this work Abstract: Retinal degeneration (RD is a heterogeneous group of inherited dystrophies leading to blindness. The N-methyl-N-nitrosourea (MNU-administered mouse is used as a pharmacologically induced RD animal model in various therapeutic investigations. The present study found the retinal neuroglobin (NGB expression in the MNU-administered mice was significantly lower than in normal controls, suggesting NGB was correlated with RD. Subsequently, an adeno-associated virus (AAV-2-mCMV-NGB vector was delivered into the subretinal space of the MNU-administered mice. The retinal NGB expression of the treated eye was upregulated significantly in both protein and mRNA levels. Further, we found NGB overexpression could alleviate visual impairments and morphological devastations in MNU-administered mice. NGB overexpression could rectify apoptotic abnormalities and ameliorate oxidative stress in MNU-administered mice, thereby promoting photoreceptor survival. The cone photoreceptors in MNU-administered mice were also sensitive to AAV-mediated NGB overexpression. Taken together, our findings suggest that manipulating NGB bioactivity via gene therapy may represent a novel therapeutic strategy against RD. Future elucidation of the exact role of NGB would advance our knowledge about the pathological mechanisms underlying RD. Keywords: neuroglobin, retinal degeneration

  10. Heparanase affects food intake and regulates energy balance in mice.

    Directory of Open Access Journals (Sweden)

    Linda Karlsson-Lindahl

    Full Text Available Mutation of the melanocortin-receptor 4 (MC4R is the most frequent cause of severe obesity in humans. Binding of agouti-related peptide (AgRP to MC4R involves the co-receptor syndecan-3, a heparan sulfate proteoglycan. The proteoglycan can be structurally modified by the enzyme heparanase. Here we tested the hypothesis that heparanase plays a role in food intake behaviour and energy balance regulation by analysing body weight, body composition and food intake in genetically modified mice that either lack or overexpress heparanase. We also assessed food intake and body weight following acute central intracerebroventricular administration of heparanase; such treatment reduced food intake in wildtype mice, an effect that was abolished in mice lacking MC4R. By contrast, heparanase knockout mice on a high-fat diet showed increased food intake and maturity-onset obesity, with up to a 40% increase in body fat. Mice overexpressing heparanase displayed essentially the opposite phenotypes, with a reduced fat mass. These results implicate heparanase in energy balance control via the central melanocortin system. Our data indicate that heparanase acts as a negative modulator of AgRP signaling at MC4R, through cleavage of heparan sulfate chains presumably linked to syndecan-3.

  11. RECK overexpression reduces invasive ability in ameloblastoma cells.

    Science.gov (United States)

    Liang, Qi-xiang; Liang, Yan-can; Xu, Zhi-ying; Chen, Wei-liang; Xie, Hong-liang; Zhang, Bin

    2014-09-01

    Ameloblastoma is a frequent odontogenic neoplasm characterized by local invasiveness and high risk of recurrence. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a tumor suppressor that inhibits metastasis and angiogenesis. The aim of this study was to investigate effects of RECK overexpression on invasive potential in ameloblastoma cells. Lentiviral vectors containing human RECK gene were created and subsequently stably transfected into immortalized ameloblastoma cell line hTERT(+) -AM. Functional characteristics of hTERT(+) -AM cells with stable RECK overexpression included proliferation, migration, invasion, and regulation of matrix metalloproteinases (MMP)-2, MMP-9 measured by zymography or commercially available assays. The stable and higher expression of RECK mRNA and protein (P 0.05). Overexpression of RECK gene significantly inhibited cell invasive ability of hTERT(+) -AM cells, suggesting RECK may be a new target for ameloblastoma treatment. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Combinatorial Method for Overexpression of Membrane Proteins in Escherichia coli*

    Science.gov (United States)

    Leviatan, Shani; Sawada, Keisuke; Moriyama, Yoshinori; Nelson, Nathan

    2010-01-01

    Membrane proteins constitute 20–30% of all proteins encoded by the genome of various organisms. Large amounts of purified proteins are required for activity and crystallization attempts. Thus, there is an unmet need for a heterologous membrane protein overexpression system for purification, crystallization, and activity determination. We developed a combinatorial method for overexpressing and purifying membrane proteins using Escherichia coli. This method utilizes short hydrophilic bacterial proteins, YaiN and YbeL, fused to the ends of the membrane proteins to serve as facilitating factors for expression and purification. Fourteen prokaryotic and mammalian membrane proteins were expressed using this system. Moderate to high expression was obtained for most proteins, and detergent solubilization combined with a short purification process produced stable, monodispersed membrane proteins. Five of the mammalian membrane proteins, overexpressed using our system, were reconstituted into liposomes and exhibited transport activity comparable with the native transporters. PMID:20525689

  13. Combinatorial method for overexpression of membrane proteins in Escherichia coli.

    Science.gov (United States)

    Leviatan, Shani; Sawada, Keisuke; Moriyama, Yoshinori; Nelson, Nathan

    2010-07-30

    Membrane proteins constitute 20-30% of all proteins encoded by the genome of various organisms. Large amounts of purified proteins are required for activity and crystallization attempts. Thus, there is an unmet need for a heterologous membrane protein overexpression system for purification, crystallization, and activity determination. We developed a combinatorial method for overexpressing and purifying membrane proteins using Escherichia coli. This method utilizes short hydrophilic bacterial proteins, YaiN and YbeL, fused to the ends of the membrane proteins to serve as facilitating factors for expression and purification. Fourteen prokaryotic and mammalian membrane proteins were expressed using this system. Moderate to high expression was obtained for most proteins, and detergent solubilization combined with a short purification process produced stable, monodispersed membrane proteins. Five of the mammalian membrane proteins, overexpressed using our system, were reconstituted into liposomes and exhibited transport activity comparable with the native transporters.

  14. Prognostic implication of NQO1 overexpression in hepatocellular carcinoma.

    Science.gov (United States)

    Lin, Lijuan; Sun, Jie; Tan, Yan; Li, Zhenling; Kong, Fanyong; Shen, Yue; Liu, Chao; Chen, Litian

    2017-11-01

    To explore the role of NQO1 overexpression for prognostic implication in hepatocellular carcinoma (HCC), NQO1 mRNA levels were detected in HCC fresh tissue samples of HCC and nontumor tissues, respectively. One hundred fifty-six cases of HCC meeting strict follow-up criteria were selected for immunohistochemical staining of NQO1 protein. Correlations between NQO1 overexpression and clinicopathological features of HCC were evaluated using χ 2 tests, survival rates were calculated using the Kaplan-Meier method, and the relationship between prognostic factors and patient 5-year survival was analyzed using Cox proportional hazards analysis. In results, the levels of NQO1 mRNA were significantly up-regulated in 14 fresh tissue samples of HCC. Immunohistochemical analysis showed that the NQO1 expression and overexpression rates were significantly higher in HCC samples compared with either adjacent nontumor tissues or normal liver tissues. NQO1 overexpression correlated to tumor size, venous infiltration and late pTNM stage of HCC. NQO1 overexpression was also related to low disease-free survival and 5-year survival rates. In the late-stage group, disease-free and 5-year survival rates of patients with NQO1 overexpression were significantly lower than those of patients without NQO1 expression. Further analysis using a Cox proportional hazards regression model revealed that NQO1 expression emerged as a significant independent hazard factor for the 5-year survival rate of patients with HCC. Therefore, NQO1 plays an important role in the progression of HCC. NQO1 may potentially be used as an independent biomarker for prognostic evaluation of HCC. Copyright © 2017. Published by Elsevier Inc.

  15. DEK protein overexpression predicts poor prognosis in pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Sun, Jie; Bi, Fangfang; Yang, Yang; Zhang, Yuan; Jin, Aihua; Li, Jinzi; Lin, Zhenhua

    2017-02-01

    DEK, a transcription factor, is involved in mRNA splicing, transcriptional control, cell division and differentiation. Recent studies suggest that DEK overexpression can promote tumorigenesis in a wide range of cancer cell types. However, little is known concerning the status of DEK in pancreatic ductal adenocarcinoma (PDAC). Based on the microarray data from Gene Expression Omnibus (GEO), the expression levels of DEK mRNA in PDAC tissues were significantly higher than levels in the adjacent non-tumor tissues. To explore the clinical features of DEK overexpression in PDAC, 87 PDAC and 52 normal pancreas tissues were selected for immunoenzyme staining of the DEK protein. Localization of the DEK protein was detected in PANC-1 pancreatic cancer cells using immunofluorescence (IF) staining. The correlations between DEK overexpression and the clinical features of PDAC were evaluated using the Chi-squared (χ2) and Fisher's exact tests. The survival rates were calculated by the Kaplan-Meier method, and the relationship between prognostic factors and patient survival was also analyzed by the Cox proportional hazard models. The expression levels of DEK mRNA in PDAC tissues were significantly higher than that in the adjacent non‑tumor tissues. The DEK protein showed a primarily nuclear staining pattern in PDAC. The positive rate of the DEK protein was 52.9% (46/87) in PDAC, which was significantly higher than that in the adjacent normal pancreatic tissues (7.7%, 4/52). DEK overexpression in PDAC was correlated with tumor size, histological grade, tumor‑node‑metastasis (TNM) stage and overall survival (OS) rates. In addition, multivariate analysis demonstrated that DEK overexpression was an independent prognostic factor along with histological grade and TNM stage in patients with PDAC. In conclusion, DEK overexpression is associated with PDAC progression and may be a potential biomarker for poor prognostic evaluation in PDAC.

  16. Overexpression of galectin-7 in mouse epidermis leads to loss of cell junctions and defective skin repair.

    Directory of Open Access Journals (Sweden)

    Gaëlle Gendronneau

    Full Text Available The proteins of the galectin family are implicated in many cellular processes, including cell interactions, polarity, intracellular trafficking, and signal transduction. In human and mouse, galectin-7 is almost exclusively expressed in stratified epithelia, notably in the epidermis. Galectin-7 expression is also altered in several human tumors of epithelial origin. This study aimed at dissecting the consequences of galectin-7 overexpression on epidermis structure and functions in vivo.We established transgenic mice specifically overexpressing galectin-7 in the basal epidermal keratinocytes and analyzed the consequences on untreated skin and after UVB irradiation or mechanical injury.The intercellular cohesion of the epidermis is impaired in transgenic animals, with gaps developing between adjacent keratinocytes, associated with loss of adherens junctions. The epidermal architecture is aberrant with perturbations in the multilayered cellular organisation of the tissue, and structural defects in the basement membrane. These transgenic animals displayed a reduced re-epithelialisation potential following superficial wound, due to a defective collective migration of keratinocytes. Finally, a single mild dose of UVB induced an abnormal apoptotic response in the transgenic epidermis.These results indicate that an excess of galectin-7 leads to a destabilisation of adherens junctions associated with defects in epidermal repair. As this phenotype shares similarities with that of galectin-7 null mutant mice, we conclude that a critical level of this protein is required for maintaining proper epidermal homeostasis. This study brings new insight into the mode of action of galectins in normal and pathological situations.

  17. Overexpression of galectin-7 in mouse epidermis leads to loss of cell junctions and defective skin repair.

    Science.gov (United States)

    Gendronneau, Gaëlle; Sanii, Sadaf; Dang, Tien; Deshayes, Frédérique; Delacour, Delphine; Pichard, Evelyne; Advedissian, Tamara; Sidhu, Sukhvinder S; Viguier, Mireille; Magnaldo, Thierry; Poirier, Francoise

    2015-01-01

    The proteins of the galectin family are implicated in many cellular processes, including cell interactions, polarity, intracellular trafficking, and signal transduction. In human and mouse, galectin-7 is almost exclusively expressed in stratified epithelia, notably in the epidermis. Galectin-7 expression is also altered in several human tumors of epithelial origin. This study aimed at dissecting the consequences of galectin-7 overexpression on epidermis structure and functions in vivo. We established transgenic mice specifically overexpressing galectin-7 in the basal epidermal keratinocytes and analyzed the consequences on untreated skin and after UVB irradiation or mechanical injury. The intercellular cohesion of the epidermis is impaired in transgenic animals, with gaps developing between adjacent keratinocytes, associated with loss of adherens junctions. The epidermal architecture is aberrant with perturbations in the multilayered cellular organisation of the tissue, and structural defects in the basement membrane. These transgenic animals displayed a reduced re-epithelialisation potential following superficial wound, due to a defective collective migration of keratinocytes. Finally, a single mild dose of UVB induced an abnormal apoptotic response in the transgenic epidermis. These results indicate that an excess of galectin-7 leads to a destabilisation of adherens junctions associated with defects in epidermal repair. As this phenotype shares similarities with that of galectin-7 null mutant mice, we conclude that a critical level of this protein is required for maintaining proper epidermal homeostasis. This study brings new insight into the mode of action of galectins in normal and pathological situations.

  18. Tobacco, alcohol, and p53 overexpression in early colorectal neoplasia

    Directory of Open Access Journals (Sweden)

    Mansukhani Mahesh

    2003-11-01

    Full Text Available Abstract Background The p53 tumor suppressor gene is commonly mutated in colorectal cancer. While the effect of p53 mutations on colorectal cancer prognosis has been heavily studied, less is known about how epidemiologic risk factors relate to p53 status, particularly in early colorectal neoplasia prior to clinically invasive colorectal cancer (including adenomas, carcinoma in situ (CIS, and intramucosal carcinoma. Methods We examined p53 status, as measured by protein overexpression, in 157 cases with early colorectal neoplasia selected from three New York City colonoscopy clinics. After collecting paraffin-embedded tissue blocks, immunohistochemistry was performed using an anti-p53 monoclonal mouse IgG2a [BP53-12-1] antibody. We analyzed whether p53 status was different for risk factors for colorectal neoplasia relative to a polyp-free control group (n = 508. Results p53 overexpression was found in 10.3%, 21.7%, and 34.9%, of adenomatous polyps, CIS, and intramucosal cases, respectively. Over 90% of the tumors with p53 overexpression were located in the distal colon and rectum. Heavy cigarette smoking (30+ years was associated with cases not overexpressing p53 (OR = 1.8, 95% CI = 1.1–2.9 but not with those cases overexpressing p53 (OR = 1.0, 95% CI = 0.4–2.6. Heavy beer consumption (8+ bottles per week was associated with cases overexpressing p53 (OR = 4.0, 95% CI = 1.3–12.0 but not with cases without p53 overexpression (OR = 1.6, 95% CI = 0.7–3.7. Conclusion Our findings that p53 overexpression in early colorectal neoplasia may be positively associated with alcohol intake and inversely associated with cigarette smoking are consistent with those of several studies of p53 expression and invasive cancer, and suggest that there may be relationships of smoking and alcohol with p53 early in the adenoma to carcinoma sequence.

  19. Matrix metalloproteinase-8 overexpression prevents proper tissue repair

    DEFF Research Database (Denmark)

    Danielsen, Patricia L; Holst, Anders V; Maltesen, Henrik R

    2011-01-01

    The collagenolytic matrix metalloproteinase-8 (MMP-8) is essential for normal tissue repair but is often overexpressed in wounds with disrupted healing. Our aim was to study the impact of a local excess of this neutrophil-derived proteinase on wound healing using recombinant adenovirus-driven tra......The collagenolytic matrix metalloproteinase-8 (MMP-8) is essential for normal tissue repair but is often overexpressed in wounds with disrupted healing. Our aim was to study the impact of a local excess of this neutrophil-derived proteinase on wound healing using recombinant adenovirus...

  20. Effect of Lowering Asymmetric Dimethylarginine (ADMA on Vascular Pathology in Atherosclerotic ApoE-Deficient Mice with Reduced Renal Mass

    Directory of Open Access Journals (Sweden)

    Johannes Jacobi

    2014-03-01

    Full Text Available The purpose of the work was to study the impact of the endogenous nitric oxide synthase (NOS inhibitor asymmetric dimethylarginine (ADMA and its degrading enzyme, dimethylarginine dimethylaminohydrolase (DDAH1, on atherosclerosis in subtotally nephrectomized (SNX ApoE-deficient mice. Male DDAH1 transgenic mice (TG, n = 39 and C57Bl/6J wild-type littermates (WT, n = 27 with or without the deletion of the ApoE gene underwent SNX at the age of eight weeks. Animals were sacrificed at 12 months of age, and blood chemistry, as well as the extent of atherosclerosis within the entire aorta were analyzed. Sham treated (no renal mass reduction ApoE-competent DDAH1 transgenic and wild-type littermates (n = 11 served as a control group. Overexpression of DDAH1 was associated with significantly lower ADMA levels in all treatment groups. Surprisingly, SNX mice did not exhibit higher ADMA levels compared to sham treated control mice. Furthermore, the degree of atherosclerosis in ApoE-deficient mice with SNX was similar in mice with or without overexpression of DDAH1. Overexpression of the ADMA degrading enzyme, DDAH1, did not ameliorate atherosclerosis in ApoE-deficient SNX mice. Furthermore, SNX in mice had no impact on ADMA levels, suggesting a minor role of this molecule in chronic kidney disease (CKD in this mouse model.

  1. αB-Crystallin overexpression in astrocytes modulates the phenotype of the BACHD mouse model of Huntington's disease.

    Science.gov (United States)

    Oliveira, Ana Osório; Osmand, Alexander; Outeiro, Tiago Fleming; Muchowski, Paul Joseph; Finkbeiner, Steven

    2016-05-01

    Huntington's disease (HD) is caused by an expanded polyglutamine (polyQ) tract in the huntingtin (htt) protein. The polyQ expansion increases the propensity of htt to aggregate and accumulate, and manipulations that mitigate protein misfolding or facilitate the clearance of misfolded proteins are predicted to slow disease progression in HD models. αB-crystallin (αBc) or HspB5 is a well-characterized member of the small heat shock protein (sHsp) family that reduces mutant htt (mhtt) aggregation and toxicity in vitro and in Drosophila models of HD. Here, we determined if overexpressing αBc in vivo modulates aggregation and delays the onset and progression of disease in a full-length model of HD, BACHD mice. Expression of sHsps in neurodegenerative disease predominantly occurs in non-neuronal cells, and in the brain, αBc is mainly found in astrocytes and oligodendrocytes. Here, we show that directed αBc overexpression in astrocytes improves motor performance in rotarod and balance beam tests and improves cognitive function in the BACHD mice. Improvement in behavioral deficits correlated with mitigation of neuropathological features commonly observed in HD. Interestingly, astrocytic αBc overexpression was neuroprotective against neuronal cell loss in BACHD brains, suggesting αBc might be acting in a non-cell-autonomous manner. At the protein level, αBc decreased the level of soluble mhtt and decreased the size of mhtt inclusions in BACHD brain. Our results support a model in which elevating astrocytic αBc confers neuroprotection through a potential non-cell-autonomous pathway that modulates mhtt aggregation and protein levels. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. The Mice Drawer System (MDS) experiment and the space endurance record-breaking mice.

    Science.gov (United States)

    Cancedda, Ranieri; Liu, Yi; Ruggiu, Alessandra; Tavella, Sara; Biticchi, Roberta; Santucci, Daniela; Schwartz, Silvia; Ciparelli, Paolo; Falcetti, Giancarlo; Tenconi, Chiara; Cotronei, Vittorio; Pignataro, Salvatore

    2012-01-01

    The Italian Space Agency, in line with its scientific strategies and the National Utilization Plan for the International Space Station (ISS), contracted Thales Alenia Space Italia to design and build a spaceflight payload for rodent research on ISS: the Mice Drawer System (MDS). The payload, to be integrated inside the Space Shuttle middeck during transportation and inside the Express Rack in the ISS during experiment execution, was designed to function autonomously for more than 3 months and to involve crew only for maintenance activities. In its first mission, three wild type (Wt) and three transgenic male mice over-expressing pleiotrophin under the control of a bone-specific promoter (PTN-Tg) were housed in the MDS. At the time of launch, animals were 2-months old. MDS reached the ISS on board of Shuttle Discovery Flight 17A/STS-128 on August 28(th), 2009. MDS returned to Earth on November 27(th), 2009 with Shuttle Atlantis Flight ULF3/STS-129 after 91 days, performing the longest permanence of mice in space. Unfortunately, during the MDS mission, one PTN-Tg and two Wt mice died due to health status or payload-related reasons. The remaining mice showed a normal behavior throughout the experiment and appeared in excellent health conditions at landing. During the experiment, the mice health conditions and their water and food consumption were daily checked. Upon landing mice were sacrificed, blood parameters measured and tissues dissected for subsequent analysis. To obtain as much information as possible on microgravity-induced tissue modifications, we organized a Tissue Sharing Program: 20 research groups from 6 countries participated. In order to distinguish between possible effects of the MDS housing conditions and effects due to the near-zero gravity environment, a ground replica of the flight experiment was performed at the University of Genova. Control tissues were collected also from mice maintained on Earth in standard vivarium cages.

  3. The Mice Drawer System (MDS experiment and the space endurance record-breaking mice.

    Directory of Open Access Journals (Sweden)

    Ranieri Cancedda

    Full Text Available The Italian Space Agency, in line with its scientific strategies and the National Utilization Plan for the International Space Station (ISS, contracted Thales Alenia Space Italia to design and build a spaceflight payload for rodent research on ISS: the Mice Drawer System (MDS. The payload, to be integrated inside the Space Shuttle middeck during transportation and inside the Express Rack in the ISS during experiment execution, was designed to function autonomously for more than 3 months and to involve crew only for maintenance activities. In its first mission, three wild type (Wt and three transgenic male mice over-expressing pleiotrophin under the control of a bone-specific promoter (PTN-Tg were housed in the MDS. At the time of launch, animals were 2-months old. MDS reached the ISS on board of Shuttle Discovery Flight 17A/STS-128 on August 28(th, 2009. MDS returned to Earth on November 27(th, 2009 with Shuttle Atlantis Flight ULF3/STS-129 after 91 days, performing the longest permanence of mice in space. Unfortunately, during the MDS mission, one PTN-Tg and two Wt mice died due to health status or payload-related reasons. The remaining mice showed a normal behavior throughout the experiment and appeared in excellent health conditions at landing. During the experiment, the mice health conditions and their water and food consumption were daily checked. Upon landing mice were sacrificed, blood parameters measured and tissues dissected for subsequent analysis. To obtain as much information as possible on microgravity-induced tissue modifications, we organized a Tissue Sharing Program: 20 research groups from 6 countries participated. In order to distinguish between possible effects of the MDS housing conditions and effects due to the near-zero gravity environment, a ground replica of the flight experiment was performed at the University of Genova. Control tissues were collected also from mice maintained on Earth in standard vivarium cages.

  4. Overexpression of the NR2A subunit in the forebrain impairs long-term social recognition and non-social olfactory memory.

    Science.gov (United States)

    Jacobs, S A; Tsien, J Z

    2014-04-01

    Animals must recognize and remember conspecifics and potential mates, and distinguish these animals from potential heterospecific competitors and predators. Despite its necessity, aged animals are known to exhibit impaired social recognition memory. As the brain ages, the ratio of NR2A:NR2B in the brain increases over time and has been postulated to underlie the cognitive decline observed during the aging process. Here, we test the hypothesis that an increased NR2A:NR2B subunit ratio underlies long-term social recognition memory. Using transgenic overexpression of NR2A in the forebrain regions, we investigated the ability of these mice to learn and remember male and female conspecifics, mice of another strain and animals of another rodent species, the rat. Furthermore, due to the importance of olfaction in social recognition, we tested the olfactory memory in the NR2A transgenic mice. Our series of behavioral experiments revealed significant impairments in the NR2A transgenic mice in long-term social memory of both male and female conspecifics. Additionally, the NR2A transgenic mice are unable to recognize mice of another strain or rats. The NR2A transgenic mice also exhibited long-term memory impairments in the olfactory recognition task. Taken together, our results provide evidence that an increased NR2A:NR2B ratio in the forebrain leads to reduced long-term memory function, including the ethologically important memories such as social recognition and olfactory memory.

  5. Insulin-like growth factor-1 overexpression in cardiomyocytes diminishes ex vivo heart functional recovery after acute ischemia.

    Science.gov (United States)

    Prêle, Cecilia M; Reichelt, Melissa E; Mutsaers, Steven E; Davies, Marilyn; Delbridge, Lea M; Headrick, John P; Rosenthal, Nadia; Bogoyevitch, Marie A; Grounds, Miranda D

    2012-01-01

    Acute insulin-like growth factor-1 administration has been shown to have beneficial effects in cardiac pathological conditions. The aim of the present study was to assess the structural and ex vivo functional impacts of long-term cardiomyocyte-specific insulin-like growth factor-1 overexpression in hearts of transgenic αMHC-IGF-1 Ea mice. Performance of isolated transgenic αMHC-IGF-1 Ea and littermate wild-type control hearts was compared under baseline conditions and in response to 20-min ischemic insult. Cardiac desmin and laminin expression patterns were determined histologically, and myocardial hydroxyproline was measured to assess collagen content. Overexpression of insulin-like growth factor-1 did not modify expression patterns of desmin or laminin but was associated with a pronounced increase (∼30%) in cardiac collagen content (from ∼3.7 to 4.8 μg/mg). Baseline myocardial contractile function and coronary flow were unaltered by insulin-like growth factor-1 overexpression. In contrast to prior evidence of acute cardiac protection, insulin-like growth factor-1 overexpression was associated with significant impairment of acute functional response to ischemia-reperfusion. Insulin-like growth factor-1 overexpression did not modify ischemic contracture development, but postischemic diastolic dysfunction was aggravated (51±5 vs. 22±6 mmHg in nontransgenic littermates). Compared with wild-type control, recovery of pressure development and relaxation indices relative to baseline performance were significantly reduced in transgenic αMHC-IGF-1 Ea after 60-min reperfusion (34±7% vs. 62±7% recovery of +dP/dt; 35±11% vs. 57±8% recovery of -dP/dt). Chronic insulin-like growth factor-1 overexpression is associated with reduced functional recovery after acute ischemic insult. Collagen deposition is elevated in transgenic αMHC-IGF-1 Ea hearts, but there is no change in expression of the myocardial structural proteins desmin and laminin. These findings suggest

  6. Metabolic profiling of follistatin overexpression: a novel therapeutic strategy for metabolic diseases

    Directory of Open Access Journals (Sweden)

    Singh R

    2018-03-01

    Full Text Available Rajan Singh,1,2 Shehla Pervin,1,2 Se-Jin Lee,3,4 Alan Kuo,5 Victor Grijalva,6 John David,7 Laurent Vergnes,8 Srinivasa T Reddy1,6 1Department of Obstetrics and Gynecology, UCLA School of Medicine, Los Angeles, CA, USA; 2Division of Endocrinology and Metabolism, Charles R. Drew University of Medicine and Science, Los Angeles, CA, USA; 3The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; 4Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, CT, USA; 5Department of Biology, California State University Dominguez Hills, CA, USA; 6Department of Molecular and Medical Pharmacology, UCLA School of Medicine, Los Angeles, CA, USA; 7Department of Comparative Medicine, Pfizer Inc, San Diego, CA, USA; 8Department of Human Genetics, UCLA School of Medicine, Los Angeles, CA, USA Background: Follistatin (Fst promotes brown adipocyte characteristics in adipose tissues.Methods: Abdominal fat volume (CT scan, glucose clearance (GTT test, and metabolomics analysis (mass spectrometry of adipose tissues from Fst transgenic (Fst-Tg and wild type (WT control mice were analyzed. Oxygen consumption (Seahorse Analyzer and lipidomics (gas chromatography was analyzed in 3T3-L1 cells.Results: Fst-Tg mice show significant decrease in abdominal fat content, increased glucose clearance, improved plasma lipid profiles and significant changes in several conventional metabolites compared to the WT mice. Furthermore, overexpression of Fst in 3T3-L1 cells resulted in up regulation of key brown/beige markers and changes in lipidomics profiles. Conclusion: Fst modulates key factors involved in promoting metabolic syndrome and could be used for therapeutic intervention. Keywords: follistatin, transgenic, adipocyte, fibroblast growth factor 21, AdipoQ

  7. ADAM12 alleviates the skeletal muscle pathology in mdx dystrophic mice

    DEFF Research Database (Denmark)

    Kronqvist, Pauliina; Kawaguchi, Nobuko; Albrechtsen, Reidar

    2002-01-01

    we examined the role of the transmembrane ADAM12, a disintegrin and metalloprotease, which is normally associated with development and regeneration of skeletal muscle. We demonstrate that ADAM12 overexpression in the dystrophin-deficient mdx mice alleviated the muscle pathology in these animals...

  8. Effect of arginine deficiency on arginine-dependent post-translational protein modifications in mice

    NARCIS (Netherlands)

    Kwikkers, Karin L.; Ruijter, Jan M.; Labruyère, Wil T.; McMahon, Kathryn K.; Lamers, Wouter H.

    2005-01-01

    Transgenic mice that overexpress arginase-I in their small-intestinal enterocytes suffer from a pronounced, but selective decrease in circulating arginine levels during the suckling period, resulting in impaired growth and development of hair, muscle and immune system. In the present study, we

  9. Cardiomyocyte-targeted overexpression of the coxsackie-adenovirus receptor causes a cardiomyopathy in association with beta-catenin signaling.

    Science.gov (United States)

    Caruso, Laura; Yuen, Stella; Smith, Julie; Husain, Mansoor; Opavsky, Mary Anne

    2010-06-01

    The coxsackie-adenovirus receptor (CAR) is an adhesion molecule found at the intercalated disc of cardiomyocytes in association with other adherens and tight junction proteins. CAR expression is increased at cardiomyocyte junctions in patients with heart failure. It is not known what contribution elevated CAR expression makes to cardiac pathology. We generated a binary transgenic mouse enabling cardiac-restricted doxycycline-regulated expression of Flag-tagged murine CAR (mCAR(+)/alpha MtTA(+) mice). Myocardial CAR levels were increased 6-fold in mCAR(+)/alpha MtTA(+) mice, localizing to intercalated discs and sarcolemma. Well at birth, mCAR(+)/alpha MtTA(+) mice developed a severe cardiomyopathy and died by 4 weeks. Cardiomyocyte hypertrophy was evident at 1 week, with increased heart:body weight ratios by 3 weeks. Disorganization and degeneration of cardiomyocytes were evident with disrupted adherens junctions. Doxycycline administration turned off transgene expression and rescued mice from the development of the cardiomyopathic phenotype. In CAR-overexpressing mCAR(+)/alpha MtTA(+) mice, adherens junction proteins were abnormally expressed. N-cadherin protein levels were 83% lower in mCAR(+)/alpha MtTA(+) hearts vs controls at 1 week, with levels subsequently increased above controls at 3 weeks. beta-catenin expression was 90% and 135% above controls at 1 and 3 weeks, respectively. Nuclear translocation of beta-catenin in cardiomyocytes of mCAR(+)/alpha MtTA(+) mice was associated with increased c-myc RNA, a target of active beta-catenin known to be associated with cardiac hypertrophy. Our study is the first to demonstrate that increased CAR expression can induce a cardiomyopathy and supports a model whereby the pathogenesis is determined by CAR stimulated beta-catenin signaling, and/or disruption of the adherens junction. (c) 2010 Elsevier Ltd. All rights reserved.

  10. Overexpression of 11β-hydroxysteroid dehydrogenase 1 in visceral ...

    African Journals Online (AJOL)

    ... expression in the adrenal cortex (zona fasciculata) was significantly lower in the dogs with HAC than in the control dogs. 11β-HSD1 overexpression and eNOS underexpression could play a role in the maintenance of hypercortisolism in dogs with HAC. Keywords: 11β-HSD1, eNOS, Glucocorticoids, Hyperadrenocorticism ...

  11. Improvement of daptomycin yield by overexpression of the ...

    African Journals Online (AJOL)

    The effects of the accessory genes flanking the non-ribosomal peptide synthetase (NRPS) genes on daptomycin production were investigated by overexpression under the control of ermE* promoter via the integrative Escherichia coli–Streptomyces vector pIB139. The yield of daptomycin was promoted significantly when ...

  12. Zinc finger protein 521 overexpression increased transcript levels of ...

    Indian Academy of Sciences (India)

    2016-02-12

    Feb 12, 2016 ... Zfp521 enhanced transcription levels of both EGFP and endogenous Fndc5. This result was confirmed by overexpression the aforementioned vectors in HEK cells and indicated that Zfp521 functions upstream of Fndc5 expression. It is most likely that Zfp521 may act through the binding to its response ...

  13. Control of cellulose biosynthesis by overexpression of a transcription factor

    Science.gov (United States)

    Han, Kyung-Hwan; Ko, Jae-Heung; Kim, Won-Chan; Kim; , Joo-Yeol

    2017-05-16

    The invention relates to the over-expression of a transcription factor selected from the group consisting of MYB46, HAM1, HAM2, MYB112, WRKY11, ERF6, and any combination thereof in a plant, which can modulate and thereby modulating the cellulose content of the plant.

  14. Over-expression of NAD kinase in Corynebacterium crenatum and ...

    African Journals Online (AJOL)

    Purpose: To improve the biosynthesis of L-arginine by overexpressing homologous NAD kinase (ppnk) in Corynebacterium crenatum SYPA5-5 and to study its impact in presence of high (HOS) and low oxygen supply (LOS). Methods: A recombinant plasmid (pJC1-tac-ppnK) harboring homologous NAD kinase (ppnk) was ...

  15. APRIL is overexpressed in cancer: link with tumor progression

    International Nuclear Information System (INIS)

    Moreaux, Jérôme; Veyrune, Jean-Luc; De Vos, John; Klein, Bernard

    2009-01-01

    BAFF and APRIL share two receptors – TACI and BCMA – and BAFF binds to a third receptor, BAFF-R. Increased expression of BAFF and APRIL is noted in hematological malignancies. BAFF and APRIL are essential for the survival of normal and malignant B lymphocytes, and altered expression of BAFF or APRIL or of their receptors (BCMA, TACI, or BAFF-R) have been reported in various B-cell malignancies including B-cell non-Hodgkin's lymphoma, chronic lymphocytic leukemia, Hodgkin's lymphoma, multiple myeloma, and Waldenstrom's macroglobulinemia. We compared the expression of BAFF, APRIL, TACI and BAFF-R gene expression in 40 human tumor types – brain, epithelial, lymphoid, germ cells – to that of their normal tissue counterparts using publicly available gene expression data, including the Oncomine Cancer Microarray database. We found significant overexpression of TACI in multiple myeloma and thyroid carcinoma and an association between TACI expression and prognosis in lymphoma. Furthermore, BAFF and APRIL are overexpressed in many cancers and we show that APRIL expression is associated with tumor progression. We also found overexpression of at least one proteoglycan with heparan sulfate chains (HS), which are coreceptors for APRIL and TACI, in tumors where APRIL is either overexpressed or is a prognostic factor. APRIL could induce survival or proliferation directly through HS proteoglycans. Taken together, these data suggest that APRIL is a potential prognostic factor for a large array of malignancies

  16. Overexpression of eIF5 or its protein mimic 5MP perturbs eIF2 function and induces ATF4 translation through delayed re-initiation.

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    Kozel, Caitlin; Thompson, Brytteny; Hustak, Samantha; Moore, Chelsea; Nakashima, Akio; Singh, Chingakham Ranjit; Reid, Megan; Cox, Christian; Papadopoulos, Evangelos; Luna, Rafael E; Anderson, Abbey; Tagami, Hideaki; Hiraishi, Hiroyuki; Slone, Emily Archer; Yoshino, Ken-Ichi; Asano, Masayo; Gillaspie, Sarah; Nietfeld, Jerome; Perchellet, Jean-Pierre; Rothenburg, Stefan; Masai, Hisao; Wagner, Gerhard; Beeser, Alexander; Kikkawa, Ushio; Fleming, Sherry D; Asano, Katsura

    2016-10-14

    ATF4 is a pro-oncogenic transcription factor whose translation is activated by eIF2 phosphorylation through delayed re-initiation involving two uORFs in the mRNA leader. However, in yeast, the effect of eIF2 phosphorylation can be mimicked by eIF5 overexpression, which turns eIF5 into translational inhibitor, thereby promoting translation of GCN4, the yeast ATF4 equivalent. Furthermore, regulatory protein termed eIF5-mimic protein (5MP) can bind eIF2 and inhibit general translation. Here, we show that 5MP1 overexpression in human cells leads to strong formation of 5MP1:eIF2 complex, nearly comparable to that of eIF5:eIF2 complex produced by eIF5 overexpression. Overexpression of eIF5, 5MP1 and 5MP2, the second human paralog, promotes ATF4 expression in certain types of human cells including fibrosarcoma. 5MP overexpression also induces ATF4 expression in Drosophila The knockdown of 5MP1 in fibrosarcoma attenuates ATF4 expression and its tumor formation on nude mice. Since 5MP2 is overproduced in salivary mucoepidermoid carcinoma, we propose that overexpression of eIF5 and 5MP induces translation of ATF4 and potentially other genes with uORFs in their mRNA leaders through delayed re-initiation, thereby enhancing the survival of normal and cancer cells under stress conditions. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Impaired glucose homeostasis in insulin-like growth factor binding protein-1 transgenic mice.

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    Rajkumar, K; Krsek, M; Dheen, S T; Murphy, L J

    1996-01-01

    Transgenic mice that overexpressed IGFBP-1 are hyperinsulinemic in the first week of life and gradually develop fasting hyperglycemia. In adult transgenic mice, the hypoglycemic response to IGF-I but not insulin or des (1-3) IGF-I was attenuated (P < 0.05) compared with wild-type mice. Furthermore, in isolated adipocytes from transgenic mice, the stimulatory effect of IGF-I but not insulin on 2-deoxy-[3H]-glucose uptake was reduced (P < 0.02). In contrast, in isolated soleus muscle, the effects of both IGF-I and insulin on 2-deoxy-3H-glucose uptake and on [3H]-glucose incorporation into glycogen were significantly reduced compared to wild-type mice. The decline in specific activity of the 2-deoxy-3H-glucose, a measure of glucose appearance in the circulation, was more marked in transgenic animals (P < 0.05). In addition, tissue uptake of glucose was significantly higher in diaphragm, heart, intestine, liver, soleus muscle, and adipose tissue from fasting transgenic mice. Plasma concentrations of alanine, lysine, and methionine were also elevated in transgenic mice. These data suggest that overexpression of IGFBP-1 attenuates the hypoglycemic effect of endogenous IGF-I, which is initially compensated for by enhanced pancreatic insulin production. However, in adult mice pancreatic insulin content is reduced, insulin resistance is demonstrable in skeletal muscle and fasting hyperglycemia develops. PMID:8878433

  18. Gene array analysis of PD-1H overexpressing monocytes reveals a pro-inflammatory profile

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    Preeti Bharaj

    2018-02-01

    Full Text Available We have previously reported that overexpression of Programmed Death -1 Homolog (PD-1H in human monocytes leads to activation and spontaneous secretion of multiple pro inflammatory cytokines. Here we evaluate changes in monocytes gene expression after enforced PD-1H expression by gene array. The results show that there are significant alterations in 51 potential candidate genes that relate to immune response, cell adhesion and metabolism. Genes corresponding to pro-inflammatory cytokines showed the highest upregulation, 7, 3.2, 3.0, 5.8, 4.4 and 3.1 fold upregulation of TNF-α, IL-1 β, IFN-α, γ, λ and IL-27 relative to vector control. The data are in agreement with cytometric bead array analysis showing induction of proinflammatory cytokines, IL-6, IL-1β and TNF-α by PD-1H. Other genes related to inflammation, include transglutaminase 2 (TG2, NF-κB (p65 and p50 and toll like receptors (TLR 3 and 4 were upregulated 5, 4.5 and 2.5 fold, respectively. Gene set enrichment analysis (GSEA also revealed that signaling pathways related to inflammatory response, such as NFκB, AT1R, PYK2, MAPK, RELA, TNFR1, MTOR and proteasomal degradation, were significantly upregulated in response to PD-1H overexpression. We validated the results utilizing a standard inflammatory sepsis model in humanized BLT mice, finding that PD-1H expression was highly correlated with proinflammatory cytokine production. We therefore conclude that PD-1H functions to enhance monocyte activation and the induction of a pro-inflammatory gene expression profile.

  19. Effects of pituitary-specific overexpression of FSHα/β on reproductive traits in transgenic boars

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    Wenting Li

    2017-10-01

    Full Text Available Abstract Background Follicle-stimulating hormone (FSH is a gonadotropin synthesized and secreted by the pituitary gland. FSH stimulates follicle development and maturation in females. It also plays an important role in spermatogenesis in males, including humans and mice. However, the effects of FSH on male pigs are largely unknown. In this study, we generated transgenic pigs to investigate the effects of FSHα/β overexpression on reproductive traits in boars. Results After five transgenic F0 founders were crossed with wide-type pigs, 193 F1 animals were obtained. Of these, 96 were confirmed as transgenic. FSHα and FSHβ mRNAs were detected only in pituitary tissue. Transgenic boars exhibited significantly higher levels of FSHα and FSHβ mRNA, serum FSH, and serum testosterone, compared to full-sib non-transgenic boars. Significant increases in testis weight, vas deferens diameter, seminiferous tubule diameter, and the number of Leydig cells were observed, suggesting that the exogenous FSHα/β affects reproductive traits. Finally, transgenic and non-transgenic boars had similar growth performance and biochemical profiles. Conclusions Pituitary-specific overexpression of FSHα/β genes is likely to impact reproductive traits positively, as indicated by enhancements in serum testosterone level, testis weight, the development of vas deferens, seminiferous tubules, and Leydig cells in transgenic boars. A high level of serum FSH induces secretion of serum testosterone, possibly by boosting the number of Leydig cells, which presumably increases the libido and the frequency of sexual activity in transgenic boars. Our study provides a preliminary foundation for the genetic improvement of reproductive traits in male pigs.

  20. Over-expression of DSCAM and COL6A2 cooperatively generates congenital heart defects.

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    Tamar R Grossman

    2011-11-01

    Full Text Available A significant current challenge in human genetics is the identification of interacting genetic loci mediating complex polygenic disorders. One of the best characterized polygenic diseases is Down syndrome (DS, which results from an extra copy of part or all of chromosome 21. A short interval near the distal tip of chromosome 21 contributes to congenital heart defects (CHD, and a variety of indirect genetic evidence suggests that multiple candidate genes in this region may contribute to this phenotype. We devised a tiered genetic approach to identify interacting CHD candidate genes. We first used the well vetted Drosophila heart as an assay to identify interacting CHD candidate genes by expressing them alone and in all possible pairwise combinations and testing for effects on rhythmicity or heart failure following stress. This comprehensive analysis identified DSCAM and COL6A2 as the most strongly interacting pair of genes. We then over-expressed these two genes alone or in combination in the mouse heart. While over-expression of either gene alone did not affect viability and had little or no effect on heart physiology or morphology, co-expression of the two genes resulted in ≈50% mortality and severe physiological and morphological defects, including atrial septal defects and cardiac hypertrophy. Cooperative interactions between DSCAM and COL6A2 were also observed in the H9C2 cardiac cell line and transcriptional analysis of this interaction points to genes involved in adhesion and cardiac hypertrophy. Our success in defining a cooperative interaction between DSCAM and COL6A2 suggests that the multi-tiered genetic approach we have taken involving human mapping data, comprehensive combinatorial screening in Drosophila, and validation in vivo in mice and in mammalian cells lines should be applicable to identifying specific loci mediating a broad variety of other polygenic disorders.

  1. Ecto-5'-Nucleotidase Overexpression Reduces Tumor Growth in a Xenograph Medulloblastoma Model.

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    Angélica R Cappellari

    Full Text Available Ecto-5'-nucleotidase/CD73 (ecto-5'-NT participates in extracellular ATP catabolism by converting adenosine monophosphate (AMP into adenosine. This enzyme affects the progression and invasiveness of different tumors. Furthermore, the expression of ecto-5'-NT has also been suggested as a favorable prognostic marker, attributing to this enzyme contradictory functions in cancer. Medulloblastoma (MB is the most common brain tumor of the cerebellum and affects mainly children.The effects of ecto-5'-NT overexpression on human MB tumor growth were studied in an in vivo model. Balb/c immunodeficient (nude 6 to 14-week-old mice were used for dorsal subcutaneous xenograph tumor implant. Tumor development was evaluated by pathophysiological analysis. In addition, the expression patterns of adenosine receptors were verified.The human MB cell line D283, transfected with ecto-5'-NT (D283hCD73, revealed reduced tumor growth compared to the original cell line transfected with an empty vector. D283hCD73 generated tumors with a reduced proliferative index, lower vascularization, the presence of differentiated cells and increased active caspase-3 expression. Prominent A1 adenosine receptor expression rates were detected in MB cells overexpressing ecto-5'-NT.This work suggests that ecto-5'-NT promotes reduced tumor growth to reduce cell proliferation and vascularization, promote higher differentiation rates and initiate apoptosis, supposedly by accumulating adenosine, which then acts through A1 adenosine receptors. Therefore, ecto-5'-NT might be considered an important prognostic marker, being associated with good prognosis and used as a potential target for therapy.

  2. Ecto-5’-Nucleotidase Overexpression Reduces Tumor Growth in a Xenograph Medulloblastoma Model

    Science.gov (United States)

    Cappellari, Angélica R.; Pillat, Micheli M.; Souza, Hellio D. N.; Dietrich, Fabrícia; Oliveira, Francine H.; Figueiró, Fabrício; Abujamra, Ana L.; Roesler, Rafael; Lecka, Joanna; Sévigny, Jean; Battastini, Ana Maria O.; Ulrich, Henning

    2015-01-01

    Background Ecto-5’-nucleotidase/CD73 (ecto-5’-NT) participates in extracellular ATP catabolism by converting adenosine monophosphate (AMP) into adenosine. This enzyme affects the progression and invasiveness of different tumors. Furthermore, the expression of ecto-5’-NT has also been suggested as a favorable prognostic marker, attributing to this enzyme contradictory functions in cancer. Medulloblastoma (MB) is the most common brain tumor of the cerebellum and affects mainly children. Materials and Methods The effects of ecto-5’-NT overexpression on human MB tumor growth were studied in an in vivo model. Balb/c immunodeficient (nude) 6 to 14-week-old mice were used for dorsal subcutaneous xenograph tumor implant. Tumor development was evaluated by pathophysiological analysis. In addition, the expression patterns of adenosine receptors were verified. Results The human MB cell line D283, transfected with ecto-5’-NT (D283hCD73), revealed reduced tumor growth compared to the original cell line transfected with an empty vector. D283hCD73 generated tumors with a reduced proliferative index, lower vascularization, the presence of differentiated cells and increased active caspase-3 expression. Prominent A1 adenosine receptor expression rates were detected in MB cells overexpressing ecto-5’-NT. Conclusion This work suggests that ecto-5’-NT promotes reduced tumor growth to reduce cell proliferation and vascularization, promote higher differentiation rates and initiate apoptosis, supposedly by accumulating adenosine, which then acts through A1 adenosine receptors. Therefore, ecto-5’-NT might be considered an important prognostic marker, being associated with good prognosis and used as a potential target for therapy. PMID:26491983

  3. CCK Response Deficiency in Synphilin-1 Transgenic Mice.

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    Wanli W Smith

    Full Text Available Previously, we have identified a novel role for the cytoplasmic protein, synphilin-1(SP1, in the controls of food intake and body weight in both mice and Drosophila. Ubiquitous overexpression of human SP1 in brain neurons in transgenic mice results in hyperphagia expressed as an increase in meal size. However, the mechanisms underlying this action of SP1 remain to be determined. Here we investigate a potential role for altered gut feedback signaling in the effects of SP1 on food intake. We examined responses to peripheral administration of cholecytokinin (CCK, amylin, and the glucagon like peptide-1 (GLP-1 receptor agonist, exendin-4. Intraperitoneal administration of CCK at doses ranging from 1-10 nmol/kg significantly reduced glucose intake in wild type (WT mice, but failed to affect intake in SP1 transgenic mice. Moreover, there was a significant attenuation of CCK-induced c-Fos expression in the dorsal vagal complex in SP1 transgenic mice. In contrast, WT and SP1 transgenic mice were similarly responsive to both amylin and exendin-4 treatment. These studies demonstrate that SP1 results in a CCK response deficiency that may contribute to the increased meal size and overall hyperphagia in synphillin-1 transgenic mice.

  4. CCK Response Deficiency in Synphilin-1 Transgenic Mice.

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    Smith, Wanli W; Smith, Megan; Yang, Dejun; Choi, Pique P; Moghadam, Alexander; Li, Tianxia; Moran, Timothy H

    2015-01-01

    Previously, we have identified a novel role for the cytoplasmic protein, synphilin-1(SP1), in the controls of food intake and body weight in both mice and Drosophila. Ubiquitous overexpression of human SP1 in brain neurons in transgenic mice results in hyperphagia expressed as an increase in meal size. However, the mechanisms underlying this action of SP1 remain to be determined. Here we investigate a potential role for altered gut feedback signaling in the effects of SP1 on food intake. We examined responses to peripheral administration of cholecytokinin (CCK), amylin, and the glucagon like peptide-1 (GLP-1) receptor agonist, exendin-4. Intraperitoneal administration of CCK at doses ranging from 1-10 nmol/kg significantly reduced glucose intake in wild type (WT) mice, but failed to affect intake in SP1 transgenic mice. Moreover, there was a significant attenuation of CCK-induced c-Fos expression in the dorsal vagal complex in SP1 transgenic mice. In contrast, WT and SP1 transgenic mice were similarly responsive to both amylin and exendin-4 treatment. These studies demonstrate that SP1 results in a CCK response deficiency that may contribute to the increased meal size and overall hyperphagia in synphillin-1 transgenic mice.

  5. Vascular endothelial growth factor-D over-expressing tumor cells induce differential effects on uterine vasculature in a mouse model of endometrial cancer

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    2010-01-01

    Background It has been hypothesised that increased VEGF-D expression may be an independent prognostic factor for endometrial cancer progression and lymph node metastasis; however, the mechanism by which VEGF-D may promote disease progression in women with endometrial cancer has not been investigated. Our aim was to describe the distribution of lymphatic vessels in mouse uterus and to examine the effect of VEGF-D over-expression on these vessels in a model of endometrial cancer. We hypothesised that VEGF-D over-expression would stimulate growth of new lymphatic vessels into the endometrium, thereby contributing to cancer progression. Methods We initially described the distribution of lymphatic vessels (Lyve-1, podoplanin, VEGFR-3) and VEGF-D expression in the mouse uterus during the estrous cycle, early pregnancy and in response to estradiol-17beta and progesterone using immunohistochemistry. We also examined the effects of VEGF-D over-expression on uterine vasculature by inoculating uterine horns in NOD SCID mice with control or VEGF-D-expressing 293EBNA tumor cells. Results Lymphatic vessels positive for the lymphatic endothelial cell markers Lyve-1, podoplanin and VEGFR-3 profiles were largely restricted to the connective tissue between the myometrial circular and longitudinal muscle layers; very few lymphatic vessel profiles were observed in the endometrium. VEGF-D immunostaining was present in all uterine compartments (epithelium, stroma, myometrium), although expression was generally low. VEGF-D immunoexpression was slightly but significantly higher in estrus relative to diestrus; and in estradiol-17beta treated mice relative to vehicle or progesterone treated mice. The presence of VEGF-D over-expressing tumor cells did not induce endometrial lymphangiogenesis, although changes were observed in existing vessel profiles. For myometrial lymphatic and endometrial blood vessels, the percentage of profiles containing proliferating endothelial cells, and the cross

  6. Vascular endothelial growth factor-D over-expressing tumor cells induce differential effects on uterine vasculature in a mouse model of endometrial cancer

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    Stacker Steven A

    2010-07-01

    Full Text Available Abstract Background It has been hypothesised that increased VEGF-D expression may be an independent prognostic factor for endometrial cancer progression and lymph node metastasis; however, the mechanism by which VEGF-D may promote disease progression in women with endometrial cancer has not been investigated. Our aim was to describe the distribution of lymphatic vessels in mouse uterus and to examine the effect of VEGF-D over-expression on these vessels in a model of endometrial cancer. We hypothesised that VEGF-D over-expression would stimulate growth of new lymphatic vessels into the endometrium, thereby contributing to cancer progression. Methods We initially described the distribution of lymphatic vessels (Lyve-1, podoplanin, VEGFR-3 and VEGF-D expression in the mouse uterus during the estrous cycle, early pregnancy and in response to estradiol-17beta and progesterone using immunohistochemistry. We also examined the effects of VEGF-D over-expression on uterine vasculature by inoculating uterine horns in NOD SCID mice with control or VEGF-D-expressing 293EBNA tumor cells. Results Lymphatic vessels positive for the lymphatic endothelial cell markers Lyve-1, podoplanin and VEGFR-3 profiles were largely restricted to the connective tissue between the myometrial circular and longitudinal muscle layers; very few lymphatic vessel profiles were observed in the endometrium. VEGF-D immunostaining was present in all uterine compartments (epithelium, stroma, myometrium, although expression was generally low. VEGF-D immunoexpression was slightly but significantly higher in estrus relative to diestrus; and in estradiol-17beta treated mice relative to vehicle or progesterone treated mice. The presence of VEGF-D over-expressing tumor cells did not induce endometrial lymphangiogenesis, although changes were observed in existing vessel profiles. For myometrial lymphatic and endometrial blood vessels, the percentage of profiles containing proliferating

  7. Bcl-2 over-expression fails to prevent age-related loss of calretinin positive neurons in the mouse dentate gyrus

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    Han Mingbo

    2006-08-01

    Full Text Available Abstract Background Cognitive performance declines with increasing age. Possible cellular mechanisms underlying this age-related functional decline remain incompletely understood. Early studies attributed this functional decline to age-related neuronal loss. Subsequent studies using unbiased stereological techniques found little or no neuronal loss during aging. However, studies using specific cellular markers found age-related loss of specific neuronal types. To test whether there is age-related loss of specific neuronal populations in the hippocampus, and subsequently, whether over-expression of the B-cell lymphoma protein-2 (Bcl-2 in these neurons could delay possible age-related neuronal loss, we examined calretinin (CR positive neurons in the mouse dentate gyrus during aging. Result In normal mice, there was an age-related loss of CR positive cells in the dentate gyrus. At the same region, there was no significant decrease of total numbers of neurons, which suggested that age-related loss of CR positive cells was due to the decrease of CR expression in these cells instead of cell death. In the transgenic mouse line over-expressing Bcl-2 in neurons, there was an age-related loss of CR positive cells. Interestingly, there was also an age-related neuronal loss in this transgenic mouse line. Conclusion These data suggest an age-related loss of CR positive neurons but not total neuronal loss in normal mice and this age-related neuronal change is not prevented by Bcl-2 over-expression.

  8. vIL-10-overexpressing human MSCs modulate naïve and activated T lymphocytes following induction of collagenase-induced osteoarthritis.

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    Farrell, Eric; Fahy, Niamh; Ryan, Aideen E; Flatharta, Cathal O; O'Flynn, Lisa; Ritter, Thomas; Murphy, J Mary

    2016-05-18

    Recent efforts in osteoarthritis (OA) research have highlighted synovial inflammation and involvement of immune cells in disease onset and progression. We sought to establish the in-vivo immune response in collagenase-induced OA and investigate the ability of human mesenchymal stem cells (hMSCs) overexpressing viral interleukin 10 (vIL-10) to modulate immune populations and delay/prevent disease progression. Eight-week-old male C57BL/6 mice were injected with 1 U type VII collagenase over two consecutive days. At day 7, 20,000 hMSCs overexpressing vIL-10 were injected into the affected knee. Control groups comprised of vehicle, 20,000 untransduced or adNull-transduced MSCs or virus alone. Six weeks later knees were harvested for histological analysis and popliteal and inguinal lymph nodes for flow cytometric analysis. At this time there was no significant difference in knee OA scores between any of the groups. A trend toward more damage in animals treated with hMSCs was observed. Interestingly there was a significant reduction in the amount of activated CD4 and CD8 T cells in the vIL-10-expressing hMSC group. vIL-10-overexpressing hMSCs can induce long-term reduction in activated T cells in draining lymph nodes of mice with collagenase-induced OA. This could lead to reduced OA severity or disease progression over the long term.

  9. Podocyte-specific overexpression of metallothionein mitigates diabetic complications in the glomerular filtration barrier and glomerular histoarchitecture: a transmission electron microscopy stereometric analysis.

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    Carlson, Edward C; Chhoun, Jennifer M; Laturnus, Donna I; Bikash, K C; Berg, Brittany; Zheng, Shirong; Epstein, Paul N

    2013-02-01

    We previously demonstrated that cellular and extracellular components of the blood-urine barrier in renal glomeruli are susceptible to damage in OVE transgenic mice, a valuable model of human diabetic nephropathy that expresses profound albuminuria. To test our hypothesis that glomerular filtration barrier damage in OVE mice may be the result of oxidative insult to podocytes, 150-day-old bi-transgenic OVENmt diabetic mice that overexpress the antioxidant metallothionein specifically in podocytes were examined by enzyme-linked immunosorbent assay for albuminuria mitigation and by unbiased transmission electron microscopy (TEM) stereometry for protection from chronic structural diabetic complications. Although blood glucose and HbA(1c) levels were indistinguishable in OVE and OVENmt animals, albuminuria was significantly reduced (average >7-fold) in OVENmt mice through 8 months of age. Interestingly, the Nmt transgene provided significant glomerular protection against diabetic nephropathic complications outside of the podocyte. Glomerular filtration barrier damage was reduced in OVENmt mice, including significantly increased area occupied by endothelial luminal fenestrations (~13%), significantly reduced glomerular basement membrane (GBM) thickening (~17%) and significantly less podocyte effacement (~18%). In addition, OVENmt mice exhibited significantly reduced glomerular volume (~50%), fewer glomerular endothelial cells (~33%), fewer mesangial cells (~57%) and fewer total glomerular cells (~40%). These results provide evidence of oxidative damage to podocytes induces primary diabetic nephropathic features including severe and sustained albuminuria, specific glomerular filtration barrier damage and alterations in glomerular endothelial and mesangial cell number. Importantly, these diabetic complications are significantly mitigated by podocyte targeted metallothionein overexpression. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Islet cell proliferation and apoptosis in insulin-like growth factor binding protein-1 in transgenic mice.

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    Dheen, S T; Rajkumar, K; Murphy, L J

    1997-12-01

    Transgenic mice which overexpress insulin-like growth factor binding protein-1 (IGFPB-1) demonstrate fasting hyperglycemia, hyperinsulinemia and glucose intolerance in adult life. Here we have examined the ontogeny of pancreatic endocrine dysfunction and investigated islet cell proliferation and apoptosis in this mouse model. In addition we have examined pancreatic insulin content in transgenic mice derived from blastocyst transfer into non-transgenic mice. Transgenic mice were normoglycemic at birth but had markedly elevated plasma insulin levels, 56.2 +/- 4.5 versus 25.4 +/- 1.5 pmol/l, p < 0.001, and pancreatic insulin concentration, 60.5 +/- 2.5 versus 49.0 +/- 2.6 ng/mg of tissue, P < 0.01, compared with wild-type mice. Transgenic mice derived from blastocyst transfer to wild-type foster mothers had an elevated pancreatic insulin content similar to that seen in pups from transgenic mice. There was an age-related decline in pancreatic insulin content and plasma insulin levels and an increase in fasting blood glucose concentrations, such that adult transgenic mice had significantly less pancreatic insulin than wild-type mice. Pancreatic islet number and the size of mature islets were increased in transgenic animals at birth compared with wild-type mice. Both islet cell proliferation, measured by 5-bromo-2'-deoxyuridine labeling, and apoptosis, assessed by the in situ terminal deoxynucleotidyl transferase and nick translation assay, were increased in islets of newborn transgenic mice compared with wild-type mice. In adult mice both islet cell proliferation and apoptosis were low and similar in transgenic and wild-type mice. Islets remained significantly larger and more numerous in adult transgenic mice despite a reduction in pancreatic insulin content. These data suggest that overexpression of IGFBP-1, either directly or indire