Wu S.-Z.,Wuhan University |
Peng F.-F.,Wuhan University |
Li J.-L.,Gannan Medical University |
Ye F.,Wuhan University |
And 3 more authors.
American Journal of Physiology - Renal Physiology | Year: 2014
Glomerular matrix accumulation is a hallmark of diabetic renal disease. Serine/threonine kinase PKC-β1 mediates glucose-induced Akt S473 phosphorylation, RhoA activation, and transforming growth factor (TGF)-β1 upregulation and finally leads to matrix upregulation in mesangial cells (MCs). It has been reported that glucose-induced PKC-β1 activation is dependent on caveolin-1 and the presence of intact caveolae in MCs; however, whether activated PKC-β1 regulates caveolin-1 expression and phosphorylation are unknown. Here, we showed that, although the caveolin-1 protein level had no significant change, the PKC-β-specific inhibitor LY-333531 blocked caveolin-1 Y14 phosphorylation in high glucose (HG)-treated MCs and in the renal cortex of diabetic rats. The Src-specific inhibitor SU-6656 prevented the HG-induced association between PKC-β1 and caveolin-1 and PKC-β1 membrane translocation, whereas PKC-β1 small interfering RNA failed to block Src activation, indicating that Src kinase is upstream of PKC-β1 activation. Although LY-333531 blocked PKC-β1 membrane translocation, it had no effect on the PKC-β1/caveolin-1 association, suggesting that PKC-β1 activation requires the interaction of caveolin-1 and PKC-β1. PKC-β1-mediated Akt S473 phosphorylation, RhoA activation, and fibronectin upregulation in response to HG were prevented by SU-6656 and nonphosphorylatable mutant caveolin-1 Y14A. In conclusion, Src activation by HG mediates the PKC-β1/caveolin-1 association and PKC-β1 activation, which assists in caveolin-1 Y14 phosphorylation by Src kinase. The downstream effects, including Akt S473 phosphorylation, RhoA activation, and fibronectin upregulation, require caveolin-1 Y14 phosphorylation. Caveolin-1 is thus an important mediator of the profibrogenic process in diabetic renal disease. © 2014 the American Physiological Society.
Jin J.,Wuhan University |
Peng C.,Wuhan University |
Wu S.-Z.,Wuhan University |
Chen H.-M.,Wuhan University |
And 2 more authors.
Acta Pharmacologica Sinica | Year: 2015
Aim: RhoA/ROCK signaling plays an important role in diabetic nephropathy, and ROCK inhibitor fasudil exerts nephroprotection in experimental diabetic nephropathy. In this study we investigated the molecular mechanisms underlying the protective actions of fasudil in a rat model of diabetic nephropathy. Methods: Streptozotocin (STZ)-induced diabetic rats, to which fasudil or a positive control drug enalapril were orally administered for 8 months. Metabolic parameters and blood pressure were assessed during the treatments. After the rats were euthanized, kidney samples were collected for histological and molecular biological studies. VEGF, VEGFR1, VEGFR2 and fibronectin expression, and Src and caveolin-1 phosphorylation in the kidneys were assessed using RT-PCR, Western blot and immunohistochemistry assays. The association between VEGFR2 and caveolin-1 was analyzed with immunoprecipitation. Results: Chronic administration of fasudil (30 and 100 mg·kg-1 ·d-1) or enalapril (10 mg/kg, bid) significantly attenuated the glomerular sclerosis and albuminuria in the diabetic rats. Furthermore, fasudil treatment prevented the upregulation of VEGF, VEGFR1, VEGFR2 and fibronectin, and the increased association between VEGFR2 and caveolin-1 in the renal cortices, and partially blocked Src activation and caveolin-1 phosphorylation on tyrosine 14 in the kidneys, whereas enalapril treatment had no effects on the VEGFR2/Src/caveolin-1 signaling pathway.Conclusion:Fasudil exerts protective actions in STZ-induced diabetic nephropathy by blocking the VEGFR2/Src/caveolin-1 signaling pathway and fibronectin upregulation. Thus, VEGFR2 may be a potential therapeutic target for the treatment of diabetic nephropathy.
Xu D.,Wuhan University |
Xu D.,Hubei Provincial Key Laboratory of Developmentally Originated Disease |
Bai J.,Wuhan University |
Zhang L.,Wuhan University |
And 6 more authors.
Toxicology Research | Year: 2015
Previous studies have indicated that the intrauterine growth retardation (IUGR) fetus is faced with a high susceptibility to adult metabolic syndrome (MS). Non-alcoholic simple fatty liver (NAFL) is considered to be the hepatic manifestation of MS. In the present study, we evaluated the susceptibility of high-fat diet-induced NAFL in female adult IUGR offspring rats, induced by prenatal nicotine exposure, and we further explored the underlying intrauterine programming mechanism for this phenomenon. The IUGR rat model was established by prenatal exposure to nicotine (2 mg kg-1 d-1), the liver tissues from female fetuses and female adult offspring fed with normal or high-fat diets were collected. The female adult offspring in the nicotine-exposed group showed low birth weights and postnatal catch-up growth, as well as severe NAFL under high-fat diets. Moreover, increased gene expression involved in the hepatic insulin-like growth factor 1 (IGF1) pathway, gluconeogenesis and lipid synthesis, and decreased gene expression of lipid output accompanied with elevated serum triglyceride levels, was observed. The female fetuses in the nicotine-exposed group showed down-regulated hepatic IGF1 pathways, and also exhibited similar patterns of increased gluconeogenesis, lipid synthesis and decreased lipid output to those in the adults. The present study demonstrates the intrauterine origin of increased susceptibility to high-fat diet-induced NAFL in female offspring rats by prenatal nicotine exposure, which is most likely mediated by "two intrauterine programming". That is, the first glucocorticoid-IGF1 axis programming induces postnatal catch-up growth, aggravates glucose and lipid metabolic disorders, and leads to an increased susceptibility to adult NAFL, while the second hepatic glucose and lipid metabolic programming enhances hepatic lipogenesis and reduces lipid oxidation and output, promoting NAFL. This journal is © The Royal Society of Chemistry 2015.
Wen Y.,Wuhan University |
Li J.,University of Lorraine |
Wang L.,Wuhan University |
Tie K.,Wuhan University |
And 5 more authors.
Arthritis Research and Therapy | Year: 2014
Introduction: The objective of this study was to investigate the possible role of UDP-glucose dehydrogenase (UGDH) in osteoarthritis (OA) and uncover whether, furthermore how interleukin-1beta (IL-1β) affects UGDH gene expression. Methods: UGDH specific siRNAs were applied to determine the role of UGDH in proteoglycan (PG) synthesis in human articular chondrocytes. Protein levels of UGDH and Sp1 in human and rat OA cartilage were detected. Then, human primary chondrocytes were treated with IL-1β to find out whether and how IL-1β could regulate the gene expression of UGDH and its trans-regulators, that is Sp1, Sp3 and c-Krox. Finally, p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 and stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) inhibitor SP600125 were used to pick out the pathway that mediated the IL-1β-modulated PGs synthesis and gene expression of UGDH, Sp1, Sp3 and c-Krox. Results: UGDH specific siRNAs markedly inhibited UGDH mRNA and protein expression, and thus led to an obvious suppression of PGs synthesis in human articular chondrocytes. UGDH protein level in human and rat OA cartilage were much lower than the corresponding controls and negatively correlated to the degree of OA. Decrease in Sp1 protein level was also observed in human and rat OA cartilage respectively. Meanwhile, IL-1β suppressed UGDH gene expression in human articular chondrocytes in the late phase, which also modulated gene expression of Sp1, Sp3 and c-Krox and increased both Sp3/Sp1 and c-Krox/Sp1 ratio. Moreover, the inhibition of SAP/JNK and p38 MAPK pathways both resulted in an obvious attenuation of the IL-1β-induced suppression on the UGDH gene expression. Conclusions: UGDH is essential in the PGs synthesis of articular chondrocytes, while the suppressed expression of UGDH might probably be involved in advanced OA, partly due to the modulation of p38 MAPK and SAP/JNK pathways and its trans-regulators by IL-1β. © 2014 Wen et al.
Zhang C.,Wuhan University |
Xu D.,Wuhan University |
Xu D.,Hubei Provincial Key Laboratory of Developmentally Originated Disease |
Luo H.,Wuhan University |
And 6 more authors.
Toxicology | Year: 2014
The hypothalamic-pituitary-adrenal (HPA) axis is one of the most important neuroendocrine axes and plays an important role in stress defense responses before and after birth. Prenatal exposure to xenobiotics, including environmental toxins (such as smoke, sulfur dioxide and carbon monoxide), drugs (such as synthetic glucocorticoids), and foods and beverage categories (such as ethanol and caffeine), affects fetal development indirectly by changing the maternal status or damaging the placenta. Certain xenobiotics (such as caffeine, ethanol and dexamethasone) may also affect the fetus directly by crossing the placenta into the fetus due to their lipophilic properties and lower molecular weights. All of these factors probably result in intrauterine programming alteration of the HPA axis, which showed a low basal activity but hypersensitivity to chronic stress. These alterations will, therefore, increase the susceptibility to adult neuropsychiatric (such as depression and schizophrenia) and metabolic diseases (such as hypertension, diabetes and non-alcoholic fatty liver disease). The "over-exposure of fetuses to maternal glucocorticoids" may be the main initiation factor by which the fetal HPA axis programming is altered. Meantime, xenobiotics can directly induce abnormal epigenetic modifications and expression on the important fetal genes (such as hippocampal glucocorticoid receptor, adrenal steroidogenic acute regulatory protein, et al) or damage by in situ oxidative metabolism of fetal adrenals, which may also be contributed to the programming alteration of fetal HPA axis. © 2014 Elsevier Ireland Ltd.
Wen Y.,Wuhan University |
Qin J.,Wuhan University |
Deng Y.,Wuhan University |
Wang H.,Wuhan University |
And 4 more authors.
Biochemical and Biophysical Research Communications | Year: 2014
UDP-galactose-4-epimerase (GALE) is a key enzyme catalyzing the interconversion of UDP-glucose and UDP-galactose, as well as UDP-N-acetylglucosamine and UDP-N-acetylgalactosamine, which are all precursors for the proteoglycans (PGs) synthesis. However, whether GALE is essential in cartilage homeostasis remains unknown. Therefore, we investigated the role of GALE in PGs synthesis of human articular chondrocytes, the GALE expression in OA, and the regulation of GALE expression by interleukin-1beta (IL-1β). Silencing GALE gene with specific siRNAs resulted in a markedly inhibition of PGs synthesis in human articular chondrocytes. GALE protein levels were also decreased in both human and rat OA cartilage, thus leading to losses of PGs contents. Moreover, GALE mRNA expression was stimulated by IL-1β in early phase, but suppressed in late phase, while the suppression of GALE expression induced by IL-1β was mainly mediated by stress-activated protein kinase/c-Jun N-terminal kinase pathway. These data indicated a critical role of GALE in maintaining cartilage homeostasis, and suggested that GALE inhibition might contribute to OA progress. © 2014 Elsevier Inc. All rights reserved.
Cheng Q.,Wuhan University |
Cheng Q.,Hubei Province Key Laboratory of Allergy and Immunology |
Dong L.,Wuhan University |
Dong L.,Hubei Province Key Laboratory of Allergy and Immunology |
And 11 more authors.
AIDS Research and Human Retroviruses | Year: 2015
RNA interference has shown great potential for the treatment of HIV-1. Vectors derived from prototype foamy viruses (PFVs) with a nonpathogenic nature are very promising gene transfer vehicles in anti-HIV gene therapy. In this article, three short hairpin RNAs (shRNAs) targeting the conserved regions of the HIV-1NL4-3 5′ long terminal repeat (LTR) were first designed. We then constructed novel recombinant PFV vector plasmids, pΦ-H1-shRNAs, expressing these shRNAs under the control of the H1 RNA promoter. To detect the efficacy of these ΔΦ-H1-shRNAs for the inhibition of HIV-1 replication, we performed a dual-luciferase reporter assay, RT-qPCR, ELISA, western blotting, and a lactate dehydrogenase (LDH) assay by transient transfection in 293T cells. The results suggest that these novel shRNAs driven by PFV vectors inhibit HIV-1 replication efficiently without cytotoxicity, with shRNA3 being the most effective. In addition, we analyzed the shRNA target sites in the 5′ LTR of HIV-1 strains other than HIV-1NL4-3 and found that these shRNAs may possibly inhibit other HIV-1 strains. © Mary Ann Liebert, Inc. 2015.
Chen X.,Wuhan University |
Zhang Y.,Wuhan University |
Shi Y.,Wuhan University |
Lian H.,Wuhan University |
And 10 more authors.
Oncotarget | Year: 2016
Abnormalities of autophagy have been implicated in an increasing number of human cancers, including glioma. To date, there is a wealth of evidence indicating that microRNAs (miRNAs) contribute significantly to autophagy in a variety of cancers. Previous studies have suggested that miR-129 functioned as an important inhibitor of the cell cycle and could promote the apoptosis of many cancer cell lines in vitro. Here, we reported that miR-129 acted as a potent inducer of autophagy. Forced expression of miR-129 could induce autophagic flux by targetedly suppressing Notch-1 in glioma cells. The autophagy induced by miR-129 could restrain the activity of mammalian target of rapamycin (mTOR) and upregulate Beclin-1. Moreover, we demonstrated that E2F transcription factor 7 (E2F7) could also trigger autophagic flux by upregulating Beclin-1 and mediating miR-129-induced autophagy. Additionally, knockdown of Notch-1 could upregulate the expression of E2F7, whereas downregulation of E2F7 alleviated shNotch-1-induced autophagic flux. In particular, knockdown of endogenous Beclin-1 could effectively reduce autophagic flux stimulated by miR-129 and E2F7. Interestingly, upon attenuation of miR-129- or E2F7-triggered autophagic flux rescued cell viability suppressed by them. More importantly, intratumoral injection of pHAGEmiR- 129 lentivirus in a nude mouse xenograft model significantly restrained tumor growth and triggered autophagy. In conclusion, these findings identify a new function for miR-129 as a potent inducer of autophagy through a novel Notch-1/E2F7/Beclin-1 axis in glioma.
PubMed | University of Lorraine, Wuhan University and Hubei Provincial Key Laboratory of Developmentally Originated Disease
Type: | Journal: Scientific reports | Year: 2015
Epidemiological evidence indicates that osteoarthritis (OA) and prenatal ethanol exposure (PEE) are both associated with low birth weight but possible causal interrelationships have not been investigated. To investigate the effects of PEE on the susceptibility to OA in adult rats that experienced intrauterine growth retardation (IUGR), and to explore potential intrauterine mechanisms, we established the rat model of IUGR by PEE and dexamethasone, and the female fetus and 24-week-old adult offspring subjected to strenuous running for 6 weeks were sacrificed. Knee joints were collected from fetuses and adult offspring for histochemistry, immunohistochemistry and qPCR assays. Histological analyses and the Mankin score revealed increased cartilage destruction and accelerated OA progression in adult offspring from the PEE group compared to the control group. Immunohistochemistry showed reduced expression of insulin-like growth factor-1 (IGF-1) signaling pathway components. Furthermore, fetuses in the PEE group experienced IUGR but exhibited a higher postnatal growth rate. The expression of many IGF-1 signaling components was downregulated, which coincided with reduced amounts of type II collagen in the epiphyseal cartilage of fetuses in the PEE group. These results suggest that PEE enhances the susceptibility to OA in female adult rat offspring by down-regulating IGF-1 signaling and retarding articular cartilage development.
PubMed | Wuhan University, French National Center for Scientific Research and Hubei Provincial Key Laboratory of Developmentally Originated Disease
Type: Journal Article | Journal: British journal of pharmacology | Year: 2016
Prenatal exposure to dexamethasone slows down fetal linear growth and bone mineralization but the regulatory mechanism remains unknown. Here we assessed how dexamethasone regulates bone development in the fetus.Dexamethasone (1mgkg(-1) day(-1) ) was injected subcutaneously every morning in pregnant rats from gestational day (GD)9 to GD20. Fetal femurs and tibias were harvested at GD20 for histological and gene expression analysis. Femurs of 12-week-old female offspring were harvested for microCT (CT) measurement. Primary chondrocytes were treated with dexamethasone (10, 50, 250 and 1000nM).Prenatal dexamethasone exposure resulted in accumulation of hypertrophic chondrocytes and delayed formation of the primary ossification centre in fetal long bone. The retardation was accompanied by reduced maturation of hypertrophic chondrocytes, decreased osteoclast number and down-regulated expression of osteocalcin and bone sialoprotein in long bone. In addition, the mitogen-inducible gene-6 (Mig6) and osteoprotegerin (OPG) expression were stimulated, and the receptor activator of NF-B ligand (RANKL) expression was repressed. Moreover, dexamethasone activated OPG and repressed RANKL expression in both primary chondrocytes and primary osteoblasts, and the knockdown of Mig6 abolished the effect of dexamethasone on OPG expression. Further, CT measurement showed loss of bone mass in femur of 12-week-old offspring with prenatal dexamethasone exposure.Prenatal dexamethasone exposure delays endochondral ossification by suppressing chondrocyte maturation and osteoclast differentiation, which may be partly mediated by Mig6 activation in bone. Bone development retardation in the fetus may be associated with reduced bone mass in later life.