miR-350通过抑制MAPK14及JNK介导心肌细胞肥大

MicroRNA-350 induces cardiomyocyte hypertrophy by inhibiting MAPK14 and JNK

目的:探讨miR-350调控MAPK14及JNK介导心肌细胞肥大的作用机制。方法:miR-350过表达及MAPK14的shRNA表达载体转染H9c2细胞,显微镜下观察细胞形态变化并测量细胞直径;免疫细胞化学法检测NFATc的转核情况;Western blotting检测靶基因MAPK14及JNK的蛋白表达;RT-PCR的方法检测MAPK14及JNK的mRNA表达。结果:细胞转染后第3天,AngⅡ,miR-350及sh-MAPK14均能诱导细胞肥大,且miR-350及sh-MAPK14促使NFATc的转核明显增多,但仅miR-350抑制JNK和MAPK14蛋白表达而不影响JNK和MAPK14mRNA水平。结论:miR-350可能是通过抑制靶基因MAPK14及JNK表达,影响NFATc的转核介导心肌肥大的。

Objectives To explore the mechanisms of miR-350 inducing cardiomyocyte hypertrophy by regula- ting MAPK14 and JNK expression. Method：miR-350 over-expression and MAPK14 shRNA vector were construc- ted and transfected into H9c2 cells. Then cells were observed in cell morphology and the area of the individual H9c2 cell was measured. Immunocytochemistry technique was used to observe nuclear translocation of NFATc. Western blotting was performed to assay the protein expression of MAPK14 and JNK, and RT-PCR was applied to detect the mRNA expression of MAPK14 and JNK. Result：Three days after transfection, the area of the indi- vidual H9c2 cell significantly increased in Ang Ⅱ ,miR-350 or sh-MAPK14 vector treated cells. Both miR-350 and sh-MAPK14 vector induced significant increase of NFATc nuclear translocation. However, only miR-350 sup- pressed MAPK14 and JNK protein expression, but without affecting mRNA levels. Conclusion： miR-350 may lead to cardiomyocyte hypertrophy by repressing both MAPK14 and JNK protein expression and affecting NFATc nu- clear translocation.