The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By usin...The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.展开更多
Background:XIAP-associated factor 1(XAF1)negatively regulates the function of the X-linked inhibitor of apoptosis protein(XIAP),a member of the IAP family that exerts antiapoptotic effects.The extracellular signal-reg...Background:XIAP-associated factor 1(XAF1)negatively regulates the function of the X-linked inhibitor of apoptosis protein(XIAP),a member of the IAP family that exerts antiapoptotic effects.The extracellular signal-regulated kinase(ERK)pathway is thought to increase cell proliferation and to protect cells from apoptosis.The aim of the study was to investigate the correlation between the ERK1/2 signaling pathway and XAF1 in colon cancer.Methods:Four human colon cancer cell lines,HCT1116 and Lovo(wildtype p53),DLD1 and SW1116(mutant p53),were used.Lovo stable transfectants with XAF1 sense and antisense were established.The effects of dominant-negative MEK1(DN-MEK1)and MEK-specific inhibitor U0126 on the ERK signaling pathway and expression of XAF1 and XIAP proteins were determined.The transcription activity of core XAF1 promoter was assessed by dual luciferase reporter assay.Cell proliferation was measured by MTT assay.Apoptosis was determined by Hoechst 33258 staining.Results:U0126 increased the expression of XAF1 in a time-and dose-dependent manner.A similar result was obtained in cells transfected with DN-MEK1 treatment.Conversely,the expression of XIAP was down-regulated.Activity of the putative promoter of the XAF1 gene was significantly increased by U0126 treatment and DN-MEK1 transient transfection.rhEGF-stimulated phosphorylation of ERK appeared to have little or no effect on XAF1 expression.Overexpression of XAF1 was more sensitive to U0126-induced apoptosis,whereas down-regulation of XAF1 by antisense reversed U0126-induced inhibition of cell proliferation.Conclusions:XAF1 expression was up-regulated by inhibition of the ERK1/2 pathway through transcriptional regulation,which required de novo protein synthesis.The results suggest that XAF1 mediates apoptosis induced by the ERK1/2 pathway in colon cancer.展开更多
Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural dif...Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.展开更多
Heart failure(HF)is a highly morbid syndrome that seriously affects the physical and mental health of patients and generates an enormous socio-economic burden.In addition to cardiac myocyte oxidative stress and apopto...Heart failure(HF)is a highly morbid syndrome that seriously affects the physical and mental health of patients and generates an enormous socio-economic burden.In addition to cardiac myocyte oxidative stress and apoptosis,which are considered mechanisms for the development of HF,alterations in cardiac energy metabolism and pathological autophagy also contribute to cardiac abnormalities and ultimately HF.Silent information regulator 1(Sirt1)and adenosine monophosphate-activated protein kinase(AMPK)are nicotinamide adenine dinucleotide(NAD+)-dependent deacetylases and phosphorylated kinases,respectively.They play similar roles in regulating some pathological processes of the heart through regulating targets such as peroxisome proliferator-activated receptorγcoactivator 1α(PGC-1α),protein 38 mitogen-activated protein kinase(p38 MAPK),peroxisome proliferator-activated receptors(PPARs),and mammalian target of rapamycin(mTOR).We summarized the synergistic effects of Sirt1 and AMPK in the heart,and listed the traditional Chinese medicine(TCM)that exhibit cardioprotective properties by modulating the Sirt1/AMPK pathway,to provide a basis for the development of Sirt1/AMPK activators or inhibitors for the treatment of HF and other cardiovascular diseases(CVDs).展开更多
Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac p...Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac protection.Our previous work found that sphingosine-1-phosphate(S1P)could ameliorate cardiac hypertrophy.In this study,we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling.Methods:Eight-week-old male C57BL/6 mice were randomly divided into a sham,transverse aortic constriction(TAC)or a TAC+S1P treatment group.Results:We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease inα-smooth muscle actin(α-SMA)and collagen type I(COL I)expression compared with the TAC group.We also found that one of the key S1P enzymes,sphingosine kinase 2(SphK2),which was mainly distributed in cytoblasts,was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro.In addition,our in vitro results showed that S1P treatment activated extracellular regulated protein kinases(ERK)phosphorylation mainly through the S1P receptor 2(S1PR2)and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine.Conclusion:These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart.This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.展开更多
目的探索CX3CR1对创伤性骨髓炎大鼠骨骼肌微纤维、ERK/MAPK信号通路及炎症反应的影响。方法选取30只SPF级SD雄性大鼠,依据随机数字表法分为健康组、模型组、CX3CR1抑制组,每组10只。除健康组外,其余各组均建立创伤性骨髓炎模型。其中健...目的探索CX3CR1对创伤性骨髓炎大鼠骨骼肌微纤维、ERK/MAPK信号通路及炎症反应的影响。方法选取30只SPF级SD雄性大鼠,依据随机数字表法分为健康组、模型组、CX3CR1抑制组,每组10只。除健康组外,其余各组均建立创伤性骨髓炎模型。其中健康组、模型组大鼠均每日常规腹腔注射生理盐水,CX3CR1干预组向残腔内注射CX3CR1中和抗体进行处理。采用ELISA法检测血清中IL-6、IL-10、IL-1β、TGF-β水平,应用改良X线Norden评分检测骨骼肌微纤维,HE染色观察病理变化,免疫印迹及PCR检测股骨组织中细胞外信号调节蛋白激酶(Extracellular regulated protein kinase,ERK1/2)、丝裂原活化蛋白激酶(Mitogen activated protein kinase,MAPK)蛋白及mRNA表达。结果与健康组比较,模型组TGF-β、IL-1β、IL-10、IL-6等炎症因子含量均升高(P<0.05);与模型组比较,CX3CR1抑制组炎症因子含量降低(P<0.05)。与健康组比较,模型组随时间推移X线Norden评分升高(P<0.05);与模型组比较,CX3CR1抑制组X线Norden评分降低(P<0.05)。HE染色显示,健康组骨质完好;模型组可见大量炎性细胞浸润、灶性脓肿及坏死灶;CX3CR1抑制组大鼠的骨质明显改善,炎症反应降低。与健康组比较,模型组ERK1/2、MAPK蛋白及mRNA表达升高(P<0.05);与模型组比较,CX3CR1抑制组ERK1/2、MAPK蛋白及mRNA表达降低(P<0.05)。结论抑制CX3CR1可改善创伤性骨髓炎大鼠的疾病反应,可能与降低炎症反应、ERK/MAPK信号通路以及改善骨骼肌微纤维相关。展开更多
基金a grant from the National Natural Sciences Foundation of China (No. 30600810)
文摘The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.
基金Shanghai Medical Key Discipline Construction Foundation(05-Ⅲ-005-017).
文摘Background:XIAP-associated factor 1(XAF1)negatively regulates the function of the X-linked inhibitor of apoptosis protein(XIAP),a member of the IAP family that exerts antiapoptotic effects.The extracellular signal-regulated kinase(ERK)pathway is thought to increase cell proliferation and to protect cells from apoptosis.The aim of the study was to investigate the correlation between the ERK1/2 signaling pathway and XAF1 in colon cancer.Methods:Four human colon cancer cell lines,HCT1116 and Lovo(wildtype p53),DLD1 and SW1116(mutant p53),were used.Lovo stable transfectants with XAF1 sense and antisense were established.The effects of dominant-negative MEK1(DN-MEK1)and MEK-specific inhibitor U0126 on the ERK signaling pathway and expression of XAF1 and XIAP proteins were determined.The transcription activity of core XAF1 promoter was assessed by dual luciferase reporter assay.Cell proliferation was measured by MTT assay.Apoptosis was determined by Hoechst 33258 staining.Results:U0126 increased the expression of XAF1 in a time-and dose-dependent manner.A similar result was obtained in cells transfected with DN-MEK1 treatment.Conversely,the expression of XIAP was down-regulated.Activity of the putative promoter of the XAF1 gene was significantly increased by U0126 treatment and DN-MEK1 transient transfection.rhEGF-stimulated phosphorylation of ERK appeared to have little or no effect on XAF1 expression.Overexpression of XAF1 was more sensitive to U0126-induced apoptosis,whereas down-regulation of XAF1 by antisense reversed U0126-induced inhibition of cell proliferation.Conclusions:XAF1 expression was up-regulated by inhibition of the ERK1/2 pathway through transcriptional regulation,which required de novo protein synthesis.The results suggest that XAF1 mediates apoptosis induced by the ERK1/2 pathway in colon cancer.
基金supported by the National Natural Science Foundation of China,No.31340024
文摘Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.
基金supported by the Natural Science Foundation of China(Grant No.:82130113)the“Xinglin Scholars”Research Promotion Program of Chengdu University of Traditional Chinese Medicine(Program No.:ZDZX2022005)+1 种基金the China Postdoctoral Science Foundation(Grant No.:2021MD703800)the Science Foundation for Youths of Science&Technology Department of Sichuan Province(Grant No.:2022NSFSC1449).
文摘Heart failure(HF)is a highly morbid syndrome that seriously affects the physical and mental health of patients and generates an enormous socio-economic burden.In addition to cardiac myocyte oxidative stress and apoptosis,which are considered mechanisms for the development of HF,alterations in cardiac energy metabolism and pathological autophagy also contribute to cardiac abnormalities and ultimately HF.Silent information regulator 1(Sirt1)and adenosine monophosphate-activated protein kinase(AMPK)are nicotinamide adenine dinucleotide(NAD+)-dependent deacetylases and phosphorylated kinases,respectively.They play similar roles in regulating some pathological processes of the heart through regulating targets such as peroxisome proliferator-activated receptorγcoactivator 1α(PGC-1α),protein 38 mitogen-activated protein kinase(p38 MAPK),peroxisome proliferator-activated receptors(PPARs),and mammalian target of rapamycin(mTOR).We summarized the synergistic effects of Sirt1 and AMPK in the heart,and listed the traditional Chinese medicine(TCM)that exhibit cardioprotective properties by modulating the Sirt1/AMPK pathway,to provide a basis for the development of Sirt1/AMPK activators or inhibitors for the treatment of HF and other cardiovascular diseases(CVDs).
基金supported by the National Natural Science Foundation of China(No.81873505).
文摘Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac protection.Our previous work found that sphingosine-1-phosphate(S1P)could ameliorate cardiac hypertrophy.In this study,we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling.Methods:Eight-week-old male C57BL/6 mice were randomly divided into a sham,transverse aortic constriction(TAC)or a TAC+S1P treatment group.Results:We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease inα-smooth muscle actin(α-SMA)and collagen type I(COL I)expression compared with the TAC group.We also found that one of the key S1P enzymes,sphingosine kinase 2(SphK2),which was mainly distributed in cytoblasts,was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro.In addition,our in vitro results showed that S1P treatment activated extracellular regulated protein kinases(ERK)phosphorylation mainly through the S1P receptor 2(S1PR2)and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine.Conclusion:These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart.This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.
文摘目的探索CX3CR1对创伤性骨髓炎大鼠骨骼肌微纤维、ERK/MAPK信号通路及炎症反应的影响。方法选取30只SPF级SD雄性大鼠,依据随机数字表法分为健康组、模型组、CX3CR1抑制组,每组10只。除健康组外,其余各组均建立创伤性骨髓炎模型。其中健康组、模型组大鼠均每日常规腹腔注射生理盐水,CX3CR1干预组向残腔内注射CX3CR1中和抗体进行处理。采用ELISA法检测血清中IL-6、IL-10、IL-1β、TGF-β水平,应用改良X线Norden评分检测骨骼肌微纤维,HE染色观察病理变化,免疫印迹及PCR检测股骨组织中细胞外信号调节蛋白激酶(Extracellular regulated protein kinase,ERK1/2)、丝裂原活化蛋白激酶(Mitogen activated protein kinase,MAPK)蛋白及mRNA表达。结果与健康组比较,模型组TGF-β、IL-1β、IL-10、IL-6等炎症因子含量均升高(P<0.05);与模型组比较,CX3CR1抑制组炎症因子含量降低(P<0.05)。与健康组比较,模型组随时间推移X线Norden评分升高(P<0.05);与模型组比较,CX3CR1抑制组X线Norden评分降低(P<0.05)。HE染色显示,健康组骨质完好;模型组可见大量炎性细胞浸润、灶性脓肿及坏死灶;CX3CR1抑制组大鼠的骨质明显改善,炎症反应降低。与健康组比较,模型组ERK1/2、MAPK蛋白及mRNA表达升高(P<0.05);与模型组比较,CX3CR1抑制组ERK1/2、MAPK蛋白及mRNA表达降低(P<0.05)。结论抑制CX3CR1可改善创伤性骨髓炎大鼠的疾病反应,可能与降低炎症反应、ERK/MAPK信号通路以及改善骨骼肌微纤维相关。
