PARP-1对高糖诱导的心肌细胞增殖的影响及机制研究

目的:研究PARP-1对高糖诱导的心肌细胞增殖的影响及可能机制。方法:用高糖处理H9C2细胞,qRT-PCR和Western blot检测细胞中PARP-1 m RNA和蛋白水平。H9C2细胞转染PARP-1 si RNA和si RNA control,q RT-PCR和Western blot检测细胞中PARP-1 m RNA和蛋白水平。用高糖处理转染PARP-1 si RNA后的H9C2细胞,CCK-8检测细胞增殖情况,硫代巴比妥酸法检测丙二醛(MDA)水平,黄嘌呤氧化酶法检测超氧化物歧化酶(SOD)水平,Western blot检测增殖细胞核抗原(PCNA)、p38丝裂原活化蛋白激酶(p38MAPK)、磷酸化的p38MAPK(p-p38MAPK)蛋白的表达。结果:高糖诱导的H9C2细胞中PARP-1 m RNA和蛋白水平明显高于正常培养的H9C2细胞(P0.05)。PARP-1 si RNA能够明显下调H9C2细胞中PARP-1 m RNA和蛋白水平。高糖处理后H9C2细胞存活率明显降低,细胞中MDA水平升高,细胞中SOD水平降低,细胞内的PCNA水平降低,p38MAPK磷酸化水平升高,与正常培养的H9C2细胞相比,差异均具有统计学意义(P0.05)。用高糖培养下调PARP-1的H9C2细胞,细胞存活率有所升高,细胞中MDA水平降低,细胞中SOD水平也升高,细胞中PCNA水平升高,细胞中p38MAPK磷酸化水平降低,与单纯高糖培养的细胞相比,差异均具有统计学意义(P0.05)。结论:PARP-1在高糖诱导的心肌细胞中表达上调,可能通过激活p38MAPK信号途径,增加细胞脂质氧化应激抑制心肌细胞增殖。

Effect and Mechanism of PARP-1 on the Proliferation of High Glucose-induced Myocardial Cells

ABSTRACT Objective: The study the effect and mechanism of PARP-1 on the proliferation of H9C2 cells induced by high glucose. Methods: H9C2 cells were treated with high glucose, and the levels of PARP-1 mRNA and protein in the cells were detected by qRT-PCR and Western blot. H9C2 cells were transfected PARP-1 siRNA and siRNA control, qRT-PCR and Western blot were used to detect PARP-1 mRNA and protein levels in the cells. H9C2 cells were transfected with PARP-1 siRNA and high glucose. CCK-8 was used to detect the cell proliferation, thiobarbituric acid method was used to detect the level of malondialdehyde. The level of SOD was detected by xanthine oxidase method. The levels of PCNA, p38MAPK and p-p38MAPK protein were detected by Western blot. Results: The level of PARP-1 mRNA and protein in H9C2 cells after high glucose was significantly higher than that of normal cultured H9C2 cells(P<0.05). PARP-1 siRNA can obviously reduce the level of PARP-1 mRNA and protein in H9C2 cells. The survival rate of H9C2 cells decreased significantly after high glucose treatment. The level of MDA in the cells was elevated, the level of SOD in the cells was reduced, the level of PCNA in the cells decreased and the level of p38MAPK phosphorylation increased, compared with the normal H9C2 cells, the difference was statistically significant(P<0.05). Down-regulation of PARP-1 H9C2 cells with high glucose, the survival rate of cells increased, the level of MDA in the cells was reduced, the level of SOD also increased in the cells, the level of PCNA in the cells was elevated, the level of p38MAPK phosphorylation in the cells was reduced, compared with pure high sugar cells, the difference was statistically significant(P<0.05). Conclusion: The expression of PARP-1 was up-regulated in cardiomyocytes induced by high glu- cose, which increase the cell lipid oxidation stress to inhibit the proliferation of cardiomyocytes by activating p38MAPK signal pathway.