Regulatory Effects of miRNA-31 on LATS2 and Cardiomyocyte Hypertrophy in Rat's Cardiomyocytein vitro / 中国循环杂志

ABSTRACT

Objective: To observe the regulatory effects of miRNA-31 (miR-31) on LATS2 and cardiomyocyte hypertrophy via down-regulating miR-31 expression in rat's cardiomyocytesin vitro. Methods: Rat's cardiomyocytes were isolated and cultured for 10 daysin vitro, according to different intervention methods, the cells were divided into 4 groups①Blank control group,②AngII intervention group,③Lentivirus with miR-31 inhibitor infection group,④Negative lentivirus infection group. On day-8, gene expressions of MiR-31, LATS2, cardiac hypertrophy ANP and β-MHC were examined by qRT-PCR; on day-10, cell morphology was observed by fluorescence staining. LATS2 protein expression was examined by Western blot analysis. Dual luciferase reporter plasmids were transfected into 293T cells, then luciferase activity was detected to identify the targeting effect of miR-31 on LATS2. Results: Compared with Blank control group, AngII intervention group showed increased gene expressions of miR31, cardiac hypertrophy ANP and β-MHC,P<0.05, enlarged cardiomyocyte surface,P<0.05; while decreased gene and proteinexpressions of LATS2,P<0.05. Compared with AngII intervention group, Lentivirus with miR-31 inhibitor infection group had down-regulated expressions of miR31, cardiac hypertrophy ANP and β-MHC,P<0.05, reduced cardiomyocyte surface, P<0.05; while slightly increased LATS2 gene expression and obviously increased protein expression,P<0.05. Dual luciferase reporter assay presented that relative luciferase activity of TRAF6-3' UTR+miR-146b was significantly decreased than TRAF6-3' UTR+miR-NC,P<0.01 and relative luciferase activity of LATS2-3' UTR+ miR-31 was signiifcantly reduced than LATS2-3' UTR-NC+miR-31,P<0.01. Conclusion: Cardiomyocytes hypertrophy could be reversed at certain degree by down-regulating miR-31; the targeting effect of miR-31 on LATS2 was involved in cardiomyocyte hypertrophyregulation.