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mRNA Decreased (mrna + decreased)
Selected AbstractsThe role of twist during palate development,DEVELOPMENTAL DYNAMICS, Issue 10 2008Wenli Yu Abstract In palatogenesis, the MEE (Medial Edge Epithelium) cells disappear when palates fuse. We hypothesize that the MEE cells undergo EMT (Epithelial-Mesenchymal Transition) to achieve mesenchyme confluence. Twist has an important role in EMT for tumor metastasis. The purpose of this study was to analyze Twist function during palatal fusion. Twist protein was expressed in palatal shelves and MEE both in vivo and in vitro just prior to fusion. Twist mRNA increased in chicken palates 3 and 6 hr after TGF,3 treatment. Palatal fusion was decreased when cultured palatal shelves were treated with 200 nM Twist siRNA and the subcellular localization of ,-catenin was altered. Twist mRNA decreased in palatal shelves treated with TGF,3 neutralizing antibody or LY294002, a specific phosphatidylinositol-3 kinase (PI-3K) inhibitor. In summary, Twist is downstream of TGF,3 and PI-3K pathways during palatal fusion. However, decreasing Twist with siRNA did not completely block palate fusion, indicating that the function of Twist may be duplicated by other transcription factors. Developmental Dynamics 237:2716,2725, 2008. © 2008 Wiley-Liss, Inc. [source] Hypertrophy and physiological death of equine chondrocytes in vitroEQUINE VETERINARY JOURNAL, Issue 6 2007Y. A. Ahmed Summary Reasons for performing study: Equine osteochondrosis results from a failure of endochondral ossification during skeletal growth. Endochondral ossification involves chondrocyte proliferation, hypertrophy and death. Until recently no culture system was available to study these processes in equine chondrocytes. Objective: To optimise an in vitro model in which equine chondrocytes can be induced to undergo hypertrophy and physiological death as seen in vivo. Methods: Chondrocytes isolated from fetal or older (neonatal, growing and mature) horses were cultured as pellets in 10% fetal calf serum (FCS) or 10% horse serum (HS). The pellets were examined by light and electron microscopy. Total RNA was extracted from the pellets, and quantitative PCR carried out to investigate changes in expression of a number of genes regulating endochondral ossification. Results: Chondrocytes from fetal foals, grown as pellets, underwent hypertrophy and died by a process morphologically similar to that seen in vivo. Chondrocytes from horses age >5 months did not undergo hypertrophy in pellet culture. They formed intramembranous inclusion bodies and the cultures included cells of osteoblastic appearance. Pellets from neonatal foals cultured in FCS resembled pellets from older horses, however pellets grown in HS underwent hypertrophy but contained inclusion bodies. Chondrocytes from fetal foals formed a typical cartilage-like tissue grossly and histologically, and expressed the cartilage markers collagen type II and aggrecan mRNA. Expression of Sox9, collagen type II, Runx2, matrix metalloproteinase-13 and connective tissue growth factor mRNA increased at different times in culture. Expression of fibroblast growth factor receptor-3 and vascular endothelial growth factor mRNA decreased with time in culture. Conclusions: Freshly isolated cells from fetal growth cartilage cultured as pellets provide optimal conditions for studying hypertrophy and death of equine chondrocytes. Potential relevance: This culture system should greatly assist laboratory studies aimed at elucidating the pathogenesis of osteochondrosis. [source] GluR- and TrkB-mediated maturation of GABAA receptor function during the period of eye openingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2005Christian Henneberger Abstract Synapse maturation includes the shortening of postsynaptic currents, due to changes in the subunit composition of respective transmitter receptors. Patch clamp experiments revealed that GABAergic inhibitory postsynaptic currents (ISPCs) of superior colliculus neurons significantly shorten from postnatal day (P)1 to P21. The change started after P6 and was steepest between P12 and P15, i.e. around eye opening. It was accompanied by enhanced sensitivity to zolpidem and increased expression of GABAAR ,1 mRNA, whereas the level of ,3 mRNA decreased. This result is consistent with the hypothesis that the IPSC kinetics of developing collicular neurons is determined by the level of ,1/,3. As ,1/,3 peaked when N -methyl-D-aspartate receptor (NMDAR)-mediated synaptic currents reached their maximum (P12) it was asked whether NMDAR activity can shape the kinetics of GABAergic IPSCs. Cultured collicular neurons were treated with NMDA or NMDAR block, and it was found that the former resulted in faster and the latter in slower IPSC decay. Group I mGluR blockade had no effect. Experiments with bdnf,/, mice revealed that, with some delay, the increase of ,1/,3 mRNA also occurred in the chronic absence of brain-derived neurotrophic factor (BDNF) and, again, this was accompanied by the shortening of IPSCs. In addition, there was an age-dependent depression of IPSC amplitudes by endogenous BDNF, which might reflect the developmental increase in the expression of GABAAR ,2L, as opposed to ,2S. Together, these experiments suggest that the GABAAR , subunit switch and the associated change in the IPSC kinetics were specifically controlled by NMDAR activity and independent on the signalling through group I mGluRs or TrkB. [source] Hypoxia induces expression of a GPI-anchorless splice variant of the prion proteinFEBS JOURNAL, Issue 11 2008Yutaka Kikuchi The human prion protein (PrP) is a glycoprotein with a glycosylphosphatidylinositol (GPI) anchor at its C-terminus. Here we report alternative splicing within exon 2 of the PrP gene (PRNP) in the human glioblastoma cell line T98G. The open reading frame of the alternatively spliced mRNA lacked the GPI anchor signal sequence and encoded a 230 amino acid polypeptide. Its product, GPI-anchorless PrP (GPI, PrPSV), was unglycosylated and soluble in non-ionic detergent, and was found in the cytosolic fraction. We also detected low levels of alternatively spliced mRNA in human brain and non-neuronal tissues. When long-term passaged T98G cells were placed in a low-oxygen environment, alternatively spliced mRNA expression increased and expression of normally spliced PrP mRNA decreased. These findings imply that oxygen tension regulates GPI, PrPSV expression in T98G cells. [source] The molecular chaperone HSP47 rapidly senses gravitational changes in myoblastsGENES TO CELLS, Issue 11 2006Asami Oguro Skeletal muscle unloading induced by spaceflight or bed rest leads to muscle atrophy. It is unclear how muscle atrophy is caused and how muscles respond to microgravity. We addressed the response of collagen and its chaperone system to gravitational forces. We show here that expression of HSP47, a collagen-specific molecular chaperone, responds to gravitational changes, including microgravity and hypergravity in vitro and in vivo. By using the method hindlimb suspension of rats, which mimics microgravity conditions, we demonstrated that the expression of Hsp47 mRNA decreased within 1 day and the mRNA levels of collagen types I and IV were subsequently reduced. In contrast, hypergravity stimulated HSP47 expression. HSP47 and collagen types I and IV were localized intracellularly in the endoplasmic reticulum and/or Golgi apparatus of myoblasts, as expected. Intriguingly, Hsp47 mRNA levels in cultured myoblasts increased significantly with hypergravity treatment at 40G for 2 h, and decreased with microgravity treatment at almost 0G for 1,2 h. Collagen mRNA levels were also altered, although changes were slower and less pronounced compared with those for HSP47. The gravity-regulated HSP47 may play a role in the maintenance of the extracellular matrix by modulating collagen production at the primary stage of adaptation. [source] Suppression of growth of pancreatic cancer cell and expression of vascular endothelial growth factor by gene silencing with RNA interferenceJOURNAL OF DIGESTIVE DISEASES, Issue 4 2008Jian WANG OBJECTIVE: To explore the anti-angiogenesis and tumor cell growth suppressive effects resulted from gene silencing by RNAi in BxPC-3 human pancreatic cancer cells. METHODS: The designation and transfection of vascular endothelial growth factor (VEGF)-siRNA lentivirus was carried out in vitro. Real-time PCR and western blot were conducted to measure the expression levels of VEGF mRNA and protein. Flow cytometry was employed to evaluate cell apoptosis and cell death. A lactate dehydrogenase (LDH) assay was used to assess the cytotoxicity of VEGF-siRNA. A 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was used to picture the cellular growth. For the in vivo study, BxPC-3 cells were injected subcutaneously into nude mice to form xenografts. The mice were divided into three groups according to the intervention used. The control group, the negative control group and the knockdown group of mice were injected with saline, an empty lentivirus vehicle and lentivirus carrying VEGF-siRNA, respectively. None of the mice died during the study. When these mice were killed, the xenografts were collected and the tumor sizes of the different groups were compared. Finally, immunohistochemistry was used to assess the VEGF expression level and microvascular density. RESULTS: After the transfection of VEGF-siRNA lentivirus, the cellular expression of VEGF mRNA decreased to 50% of the control and the VEGF protein in the BxPC-3 cells decreased to 30% of the control. Apoptosis and cell death increased after transfection of the VEGF-siRNA lentivirus. The LDH assay showed high cytotoxicity induced by VEGF-siRNA lentivirus transfection. The MTT assay showed slower cellular growth in the knockdown cells. Tumor growth suppression was observed in nude mice that had received the VEGF-siRNA lentivirus transfection, and the tumor sizes of the xenografts in this group were clearly smaller than those in other two groups. VEGF expression and microvascular density were significantly decreased. CONCLUSION: Vascular endothelial growth factor gene silencing via VEGF-siRNA can effectively inhibit the production of VEGF and exert an anti-angiogenesis and tumor cell growth suppressive effect both in vitro and in vivo. [source] Roles of Corticotropin-Releasing Factor, Neuropeptide Y and Corticosterone in the Regulation of Food Intake In Xenopus laevisJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2004E. J. Crespi Abstract In mammals, hypothalamic control of food intake involves counterregulation of appetite by anorexigenic peptides such as corticotropin-releasing factor (CRF), and orexigenic peptides such as neuropeptide Y (NPY). Glucocorticoids also stimulate food intake by inhibiting CRF while facilitating NPY actions. To gain a better understanding of the diversity and evolution of neuroendocrine feeding controls in vertebrates, we analysed the effects of CRF, NPY and glucocorticoids on food intake in juvenile Xenopus laevis. We also analysed brain CRF and NPY mRNA content and plasma corticosterone concentrations in relation to nutritional state. Intracerebroventricular (i.c.v.) injection of ovine CRF suppressed food intake while CRF receptor antagonist ,helical CRF(9,41) significantly increased food intake relative to uninjected and placebo controls. By contrast, i.c.v. injection of frog NPY and short-term corticosterone treatment increased food intake. Semi-quantitative reverse transcription-polymerase chain reaction analyses showed that CRF and NPY mRNA fluctuated with food intake in the brain region containing the mid-posterior hypothalamus, pretectum, and optic tectum: CRF mRNA decreased 6 h after a meal and remained low through 31 days of food deprivation; NPY mRNA content also decreased 6 h after a meal, but increased to prefeeding levels by 24 h. Plasma corticosterone concentration increased 6 h after a meal, returned to prefeeding levels by 24 h, and did not change with prolonged food deprivation. This postprandial increase in plasma corticosterone may be related to the subsequent increase in plasma glucose and body water content that occurs 24 h postfeeding. Overall, our data support the conclusion that, similar to other vertebrates, CRF is anorexigenic while NPY is orexigenic in X. laevis, and CRF secretion modulates food intake in the absence of stress by exerting an inhibitory tone on appetite. Furthermore, the stress axis is activated in response to food intake, but in contrast to mammals and birds is not activated during periods of food deprivation. [source] Lasting changes in NMDAR1 mRNA level in various regions of cerebral cortex in epileptogenesis of amygdaloid-kindled ratPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2000Shiuichi Kikuchi MD Abstract The involvement of NMDA receptor subunit, NR1, with kindling phenomenon has been reported, but the role of NR1 in epileptogenesis is still unknown. We have examined the expression levels of NR1 mRNA in the cerebral cortices of amygdaloid-kindled rats. Northern blot analysis showed a significant increase in NR1 mRNA expression level in the ipsilateral frontal and temporal cortices at 4 weeks after the last generalized seizure. At the same time, NR1 mRNA decreased in the bilateral piriform cortices. These data suggest that NR1-mediated transmission may have an impact in the neurobiological basis of enduring epileptogenesis. [source] Molecular dynamics of detoxification and toxin-tolerance genes in brown planthopper (Nilaparvata lugens Stål., Homoptera: Delphacidae) feeding on resistant rice plantsARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2005Zhifan Yang Abstract To investigate the molecular response of brown planthopper, Nilaparvata lugens (BPH) to BPH-resistant rice plants, we isolated cDNA fragments of the genes encoding for carboxylesterase (CAR), trypsin (TRY), cytochrome P450 monooxygenase (P450), NADH-quinone oxidoreductase (NQO), acetylcholinesterase (ACE), and Glutathione S-transferase (GST). Expression profiles of the genes were monitored on fourth instar nymphs feeding on rice varieties with different resistance levels. Northern blot hybridization showed that, compared with BPH reared on susceptible rice TN1, expression of the genes for P450 and CAR was apparently up-regulated and TRY mRNA decreased in BPH feeding on a highly resistant rice line B5 and a moderately resistant rice variety MH63, respectively. Two transcripts of GST increased in BPH feeding on B5; but in BPH feeding on MH63, this gene was inducible and its expression reached a maximum level at 24 h, and then decreased slightly. The expression of NQO gene was enhanced in BPH on B5 plants but showed a constant expression in BPH on MH63 plants. No difference in ACE gene expression among BPH on different rice plants was detected by the RT-PCR method. The results suggest these genes may play important roles in the defense response of BPH to resistant rice. Arch. Insect Biochem. Physiol. 59:59,66, 2005. © 2005 Wiley-Liss, Inc. [source] Effect of high-dose methylprednisolone treatment on Th17 cells in patients with multiple sclerosis in relapseACTA NEUROLOGICA SCANDINAVICA, Issue 4 2009M. Liu Objectives,,, Growing evidences have suggested that Th17 cells are involved in the pathogenic mechanisms of multiple sclerosis (MS). Treatment with high-dose intravenous methylprednisolone (IVMP) has beneficial effects on functional recovery in patients with MS during relapse. The present study was designed to analyze the influences of IVMP on Th17 cells in patients with MS after a 5-day high-dose IVMP treatment. Materials and methods,,, Th17 cell count and the production of IL-17 in peripheral blood mononuclear cells (PBMCs) were measured using flow cytometry and ELISA respectively. Quantitative real-time PCR was performed to analyze the mRNA expression of Th17 cell-related factors (IL-17, RORc and IL-23R) in PBMCs. Results,,, A significant reduction in IL-17 production and Th17 cells count in PBMCs was found in patients with MS after IVMP treatment. Moreover, the expression of IL-17, IL-23R and RORc mRNA decreased significantly after IVMP treatment. Conclusions,,, Treatment with methylprednisolone has a suppressive effect on Th17 cells and may be related to its clinical efficiency. [source] G,q -PROTEIN CARBOXYL TERMINUS IMITATION POLYPEPTIDE GCIP-27 ATTENUATES CARDIAC HYPERTROPHY IN VITRO AND IN VIVOCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2007Hai-Gang Zhang SUMMARY 1Various Gq -protein-coupled receptors, such as ,1 -adrenoceptors, angiotension AT1 receptors, endothelin ETA receptors, neuropeptide Y1 receptors etc., contribute to cardiac hypertrophy. In G-protein signalling pathways, the carboxyl terminus of the G, subunit plays a vital role within G-protein,receptor interaction. The present study was designed to explore the effects of the synthetic G,q carboxyl terminal imitation peptide GCIP-27 on cardiac hypertrophy. 2Hypertrophy of rat cultured cardiomyocytes was induced by noradrenaline (NA) or angiotensin (Ang) II in vitro. Protein content, [3H] incorporation and [Ca2+]i were determined in cardiomyocytes cultured with GCIP-27. Three in vivo animal models of cardiac hypertrophy were prepared using intraperitoneal injections of NA in mice and rats and suprarenal abdominal aortic stenosis in rats. After treatment with GCIP-27 (10,100 µg/L) for 15 or 20 days, indices of cardiac hypertrophy were measured. The effect of GCIP-27 on the mRNA expression of c-fos and c-jun was detected using reverse transcription,polymerase chain reaction. 3At 10,100 µg/L, GCIP-27 significantly decreased protein content and [3H]-leucine incorporation in cultured cardiomyocytes compared with 1 µmol/L NA- and 1 µmol/L AngII-treated groups. After treatment with GCIP-27 (10, 30 or 100 µg/kg) for 15 days, the heart index (HI) and left ventricular index (LVI) in mice decreased significantly compared with the NA control group. In rats, GCIP-27 significantly reduced HI and LVI compared with the NA and aortic stenosis groups. Moreover, [Ca2+]i in cardiomyocytes in the GCIP-27 (3, 10, 30 µg/L)-treated groups was lower than that in the control groups. Expression of c-fos and c-jun mRNA decreased significantly in the myocardium from 5,45 µg/L GCIP-27-treated rats compared with NA controls. 4The results indicate that GCIP-27 can attenuate cardiac hypertrophy effectively in various models in vitro and in vivo. [source] Quantitive cytokine mRNA expression profiles in the colonic mucosa of patients with steroid naïve ulcerative colitis during active and quiescent diseaseINFLAMMATORY BOWEL DISEASES, Issue 3 2009Reikei Matsuda MD Abstract Background: Cytokines have validated roles in the immunopathogenesis of inflammatory bowel disease (IBD). This study was to investigate the expressions of tumor necrosis factor (TNF)-,, interleukin (IL)-6, IL-8, and IL-10 mRNAs in the colonic mucosa of patients with ulcerative colitis (UC) during active and quiescent UC. Methods: At colonoscopy, biopsies were taken from inflamed and non-inflamed mucosa of patients with steroid-naive UC (n = 15), non-IBD inflammatory colitis controls (ICC, n = 6), and non-colitis controls (NCC, n = 14). The presence of extensive mononuclear cells and neutrophils infiltrate in the lamina propria, cryptitis, and epithelial damage defined an inflammatory lesion in the mucosa. Quantitative cytokine mRNA expressions in biopsies were measured by real-time polymerase chain reaction (PCR). Results: Of 15 UC patients, 3 remitted with 5-aminosalicylate and 11 received granulocytapheresis; of these, 10 remitted. At baseline, IL-6, IL-8, TNF-,, and IL-10 mRNAs were high in inflamed mucosa compared with NCC (P < 0.01). In active UC, IL-6, IL-8 and IL-10 mRNAs were high compared with non-inflamed mucosa (P = 0.03, P = 0.03, P < 0.05, respectively). Both TNF-, mRNA (P = 0.03) and IL-6 mRNA (P = 0.04) were higher in UC compared with ICC. Even in non-inflamed mucosa, IL-8 and TNF-, mRNA expressions were high compared with NCC. Both IL-6 and IL-8 mRNAs decreased to normal levels after granulocytapheresis. Conclusions: During active UC, all 4 cytokine mRNA levels were high; only IL-6 and IL-8 mRNAs decreased to normal levels during remission. IL-8 mRNA was high even at sites of endoscopically quiescent UC during active disease. Steroid naïve patients respond well to granulocytapheresis. (Inflamm Bowel Dis 2008) [source] | ||||||||||||||||