MicroRNA-99a促进新生小鼠心肌细胞增殖

Overexpression of microRNA-99a Promotes the Proliferation of Cardiomyocytes

目的有效地促进心肌细胞增殖为亟待发展的治疗策略。本研究拟观察高表达microRNA-99a(miR-99a)对体外培养心肌细胞增殖的影响并对其相关机制进行探讨。方法利用高表达miR-99a的慢病毒载体转染体外培养的乳鼠心肌细胞,诱导其在乳鼠心肌细胞中高表达。采用噻唑蓝法、EDU法检测乳鼠心肌细胞增殖能力;Western blot检测乳鼠心肌细胞ERK1/2蛋白表达及其蛋白磷酸化水平。结果 miR-99a在乳鼠心肌细胞高表达后,噻唑蓝法、EDU法检测结果均表明:miR-99a转染组细胞增殖能力明显高于空病毒转染对照组(P<0.05)。Western blot检测发现miR-99a病毒转染组ERK1/2蛋白磷酸化水平较对照组明显升高(P<0.05)。结论 miR-99a高表达能促进乳鼠心肌细胞增殖,其机制可能部分通过激活Erk1/2通路。

Aim Promoting cardiac regeneration is therapeutic strategy to be developed urgently. In present study, we investigated the effects of overexpression of microRNA-99a（miR-99a） on eardiomyocytes proliferation of neonatal mice as well as its potential mechanism. Methods Cardiomyocytes of neonatal mice were infected by lentiviral-miR- 99a（ LV-miR-99a）. Cardiomyocytes proliferation were identified by thiazolyl blue （MTI＇） and 5-ethynyl-2＇ -deoxyuridine （EDU） assay. Western blot was used to assess the protein expression of Erkl/2 and its phosphorylation levels in cardio- myocytes. Results MTT assay and EDU assay both showed that cardiomyoeytes proliferation were significantly higher in miR-99a over-expression group than in the control group （ P 〈 0. 05 ）. The phosphorylation levels of erkl/2 was also significantly higher than that in the control group （ P 〈 0. 05 ）, Conclusions miR-99a overexpression can promote cardiomyocytes proliferation. This effect may be partly mediated through activation of erkl/2.