Objective To investigate the effect of emodin on high glucose(HG)-induced podocyte apoptosis and whether the potential anti-apoptotic mechanism of emodin is related to induction of adenosine-monophosphate-activated pr...Objective To investigate the effect of emodin on high glucose(HG)-induced podocyte apoptosis and whether the potential anti-apoptotic mechanism of emodin is related to induction of adenosine-monophosphate-activated protein kinase(AMPK)/mammalian target of rapamycin(mTOR)-mediated autophagy in podocytes(MPC5 cells)in vitro.Methods MPC5 cells were treated with different concentrations of HG(2.5,5,10,20,40,80 and 160 mmol/L),emodin(2,4,8µmol/L),or HG(40 mmol/L)and emodin(4µmol/L)with or without rapamycin(Rap,100 nmol/L)and compound C(10µmol/L).The viability and apoptosis of MPC5 cells were detected using cell counting kit-8(CCK-8)assay and flow cytometry analysis,respectively.The expression levels of cleaved caspase-3,autophagy marker light chain 3(LC3)Ⅰ/Ⅱ,and AMPK/mTOR signaling pathway-related proteins were determined by Western blot.The changes of morphology and RFP-LC3 fluorescence were observed under microscopy.Results HG at 20,40,80 and 160 mmol/L dose-dependently induced cell apoptosis in MPC5 cells,whereas emodin(4µmol/L)significantly ameliorated HG-induced cell apoptosis and caspase-3 cleavage(P<0.01).Emodin(4µmol/L)significantly increased LC3-Ⅱ protein expression levels and induced RFP-LC3-containing punctate structures in MPC5 cells(P<0.01).Furthermore,the protective effects of emodin were mimicked by rapamycin(100 nmol/L).Moreover,emodin increased the phosphorylation of AMPK and suppressed the phosphorylation of mTOR.The AMPK inhibitor compound C(10µmol/L)reversed emodin-induced autophagy activation.Conclusion Emodin ameliorated HG-induced apoptosis of MPC5 cells in vitro that involved induction of autophagy through the AMPK/mTOR signaling pathway,which might provide a potential therapeutic option for diabetic nephropathy.展开更多
基金Supported by the Chinese Medicine Research Project of Hubei Provincial Health Commission(No.ZY2019Q024)Scientific Research Project of Wuhan Municipal Health Commission(No.WX20B11)Scientific Research Project of Wuhan Municipal Health Commission(No.WZ20C01)。
文摘Objective To investigate the effect of emodin on high glucose(HG)-induced podocyte apoptosis and whether the potential anti-apoptotic mechanism of emodin is related to induction of adenosine-monophosphate-activated protein kinase(AMPK)/mammalian target of rapamycin(mTOR)-mediated autophagy in podocytes(MPC5 cells)in vitro.Methods MPC5 cells were treated with different concentrations of HG(2.5,5,10,20,40,80 and 160 mmol/L),emodin(2,4,8µmol/L),or HG(40 mmol/L)and emodin(4µmol/L)with or without rapamycin(Rap,100 nmol/L)and compound C(10µmol/L).The viability and apoptosis of MPC5 cells were detected using cell counting kit-8(CCK-8)assay and flow cytometry analysis,respectively.The expression levels of cleaved caspase-3,autophagy marker light chain 3(LC3)Ⅰ/Ⅱ,and AMPK/mTOR signaling pathway-related proteins were determined by Western blot.The changes of morphology and RFP-LC3 fluorescence were observed under microscopy.Results HG at 20,40,80 and 160 mmol/L dose-dependently induced cell apoptosis in MPC5 cells,whereas emodin(4µmol/L)significantly ameliorated HG-induced cell apoptosis and caspase-3 cleavage(P<0.01).Emodin(4µmol/L)significantly increased LC3-Ⅱ protein expression levels and induced RFP-LC3-containing punctate structures in MPC5 cells(P<0.01).Furthermore,the protective effects of emodin were mimicked by rapamycin(100 nmol/L).Moreover,emodin increased the phosphorylation of AMPK and suppressed the phosphorylation of mTOR.The AMPK inhibitor compound C(10µmol/L)reversed emodin-induced autophagy activation.Conclusion Emodin ameliorated HG-induced apoptosis of MPC5 cells in vitro that involved induction of autophagy through the AMPK/mTOR signaling pathway,which might provide a potential therapeutic option for diabetic nephropathy.
