Effects of DNMT1 on high glucose-induced apoptosis and inflammatory cytokine release in podocytes via SOCS1
This study was designed to explore the effect of DNA methyltransferase 1(DNMT1)on podocyte apoptosis and inflammatory cytokine release induced by high glucose(HG),and analyze the related molecular mechanisms.Podocyte MPC-5 cells were cultured in vitro and divided into control and HG groups.DNMT1 and SOCS1 were either silenced or overexpressed using small RNA interference technology and liposome transfection technology.The expression levels of DNMT1 and SOCS1 genes were measured using qRT-PCR.Apoptosis was assessed by flow cytometry,while ELISA was employed to determine the levels of inflammatory factors such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),interleukin-1β(IL-1β),and monocyte chemoattractant protein-1(MCP-1).Western blot was used to detect the expression of DNMT1,SOCS1 proteins,and the proteins involved in the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathway.Data showed that HG elevated MPC-5 cell apoptosis rate,the level of inflammatory factors and DNMT1 mRNA expression,and the expression of DNMT1,p-JAK2 and p-STAT3 proteins,while reduced SOCS1 mRNA and protein expression(P<0.05).Both silencing DNMT1 and overexpressing SOCS1 resulted in reduce of MPC-5 cell apoptosis rate,inflammatory factors level,p-JAK2 and p-STAT3 proteins expression(P<0.05).Additionally,silencing DNMT1 increased SOCS1 mRNA and protein expressions(P<0.05).Conversely,silencing SOCS1 counteracted the effects of DNMT1 silencing on MPC-5 cell apoptosis,inflammation,p-JAK2 and p-STAT3 proteins expression.Therefore,silencing DNMT1 expression can reduce the apoptosis and inflammation of podocytes induced by HG,and its mechanism may be related to the inhibition of JAK2/STAT3 signaling pathway activation by upregulating SOCS1 expression.