激动线粒体乙醛脱氢酶2对高糖诱导的大鼠心肌细胞MMP-14及TIMP-4的影响

Effects of activation of mitochondrial aldehyde dehydrogenase 2 on MMP-14 and TIMP-4 in high glucose induced rat cardiomyocytes injury

目的探讨基质金属蛋白酶14(MMP-14)、基质金属蛋白酶组织抑制因子4(TIMP-4)是否参与线粒体乙醛脱氢酶2(ALDH2)抗高糖诱导的原代大鼠心肌细胞损伤。方法不同浓度葡萄糖干预原代大鼠心肌细胞,MTT法检测不同时间点细胞活力,确定高糖诱导的心肌细胞损伤模型。实验分为正常对照组(NG,5.5 mmol·L^(-1))、NG+ALDH2激动剂Alda-1组、高糖组(HG,30 mmol·L^(-1)),HG+Alda-1组。MTT法和DHE染色分别检测细胞活力及氧化应激水平,Western blot检测ALDH2、MMP-14、TIMP-4蛋白表达。结果根据细胞活力检测确定30 mmol·L^(-1)葡萄糖干预48 h为损伤模型。与NG组比较,HG组细胞活力、ALDH2、MMP-14蛋白表达、MMP-14/TIMP-4比值均降低,氧化应激、TIMP-4蛋白水平升高;与HG组比较,Alda-1干预后细胞活力、ALDH2及MMP-14蛋白表达、MMP-14/TIMP-4比值升高,氧化应激及TIMP-4蛋白表达降低。结论激动ALDH2可改善高糖引起的心肌细胞损伤,可能与抑制氧化应激、促进MMP-14蛋白表达、抑制TIMP-4蛋白表达有关。

Aim To observe whether matrix metalloproteinase-14（ MMP-14） and tissue matrix metalloproteinase inhibitor-4（ TIMP-4） were involved in the cardiac-protection of mitochondrial aldehyde dehydrogenase 2（ ALDH2） against high glucose induced rat primary cardiomyocyte injury.Methods Rat primary cardiomyocytes were cultured.The cardiomyocyte viability was detected by MTT assay at different concentration of glucose at different time point.After established high glucose-induced cardiomyocytes injury model,cardiomyocytes were randomly divided into 4 groups：normal control group（ NG,glucose at 5.5 mmol·L^（-1））,NG ＋ Alda-1 group（ Alda-1 at 20 μmol·L^（-1））,high glucose group（ HG,glucose at 30 mmol·L^（-1））and HG ＋ Alda-1 group.The cell viability at 48 h and oxidative stress level were detected by MTT and DHE staining methods.The protein expressions of ALDH2,MMP-14 and TIMP-4 were determined by Western blot.Results The cardiomyocytes injury model was established according to the cell activity result.Compared with NG group,the cell viability,the protein expressions of ALDH2,MMP-14,the ratio of MMP-14/TIMP-4 were decreased, TIMP-4 protein expression and the level of oxidative stress were increased in HG group.Compared with HG group, in HG ＋ Alda-1 group,the cell viability,the protein expressions of ALDH2,MMP-14,the ratio of MMP-14/TIMP-4 were increased,the levels of oxidative stress and TIMP-4 protein expression were decreased.Conclusion Activation of mitochondrial ALDH2 may relieve high glucose induced cardiomyocytes injury.The protective effect was likely related to the inhibition of oxidative damage,down-regulation of MMP-14 and up-regulation of TIMP-4 proteins.