MiR 138 promotes smooth muscle cells proliferation and migration in db/db mice through down regulation of SIRT1.
BACKGROUND Diabetic vascular smooth muscle cells (VSMCs) exhibit significantly increased rates of proliferation and migration, which was the most common pathological change in atherosclerosis. In addition, the study about the role for miRNAs in the regulation of VSMC proliferation is just beginning to emerge and additional miRNAs involved in VSMC proliferation modulation should be identified. METHODS The expression of miR 138 and SIRT1 were examined in SMCs separated from db/db mice and in SMC lines C 12511 exposed to high glucose with qRT PCR and western blot. The regulation of miR 138 on the expression of SMCs was detected with luciferase report assay. VSMCs proliferation and migration assays were performed to examine the effect of miR 138 inhibitor on VSMCs proliferation and migration. RESULTS We discovered that higher mRNA level of miR 138 and reduced expression of SIRT1 were observed in SMCs separated from db/db mice and in SMC lines C 12511. Moreover, luciferase report assay showed that the activity of SIRT1 3' UTR was highly increased by miR 138 inhibitor and reduced by miR 138 mimic. In addition, we examined that the up regulation of NF kB induced by high glucose in SMCs was reversed by resveratrol and miR 138 inhibitor. MTT and migration assays showed that miR 138 inhibitor attenuated the proliferation and migration of smooth muscle cells. CONCLUSION In this study, we revealed that miR 138 might promote proliferation and migration of SMC in db/db mice through suppressing the expression of SIRT1.
Biochemical and biophysical research communications