Increased foxo1 dna methylation level in homocysteine-induced podocyte apoptosis / 中国组织工程研究

ABSTRACT

BACKGROUND: The increase of homocysteine can lead to renal injury and podocyte apoptosis, but the specific mechanism is not clear. OBJECTIVE: To investigate the effect of Forkhead box O1 (FoxO1) and its DNA methylation in podocyte apoptosis induced by homocysteine. METHODS: Mouse renal podocytes (MPC-5) were cultured in vitro and divided into control group (0 μmol/L homocysteine) and homocysteine group (80 μmol/L homocysteine). After 48 hours of intervention, the expression of podocyte apoptosis-related proteins Bax, caspase12 and Bcl-2 was detected by immunofluorescence technique; the expression level of FoxO1 mRNA was detected by real-time fluorescence quantitative PCR; the protein expression levels of FoxO1 and DNMT1 were detected by western blot; DNA methylation level of FoxO1 was detected by nested methylation-specific PCR. RESULTS AND CONCLUSION: Compared with the control group, the expression levels of Bax and caspase12 protein in podocytes of the homocysteine group were significantly increased, while the expression of Bcl-2 protein was significantly decreased. The expression levels of FoxO1 mRNA and protein were significantly decreased in the homocysteine group compared with the control group (P < 0.01). At the same time, the methylation level of FoxO1 DNA in the homocysteine group was significantly higher than that in the control group (P < 0.01), and the expression of DNMT1 protein in podocytes in the homocysteine group was significantly higher than that in the control group (P < 0.01). To conclude, FoxO1 DNA hypermethylation plays a significant role in podocyte apoptosis induced by homocysteine, whereas DNMT1 participates in homocysteine-induced podocyte apoptosis.