岩白菜素对大鼠心肌细胞的缺氧/复氧损伤保护作用的机制研究

Bergenia alleviates simulate ischemia/reperfusion injury of cardiomyocytes in rats via SIRT1/PCG-1 α

目的 探究岩白菜素(Ber)减轻大鼠心肌细胞(H9C2)缺氧/复氧损伤(SI/R)的分子机制。方法 建立H9C2缺氧/复氧损伤模型,通过免疫印迹法检测关键分子的表达,通过末端标记法染色和乳酸脱氢酶释放量检测细胞损伤,通过二氯荧光素染色及丙二醛(MDA)检测细胞内活性氧(ROS)水平,通过分别给予EX-527和SR-18292抑制沉默交配型信息调控2同源物1(SIRT1)和过氧化物酶体增殖物受体共激活因子-1α(PGC-1α)。实验按干预方法不同分组,分别为Bey干预组(SI/R+Ber)、Bey+SIRT1抑制剂组(SI/R+Ber+EX-527)、对照组(SI/R+PBS)。SI/R+Ber组加入含有100μM的Ber培养基进行干预,SI/R+Ber+EX-527组加入含有100μM的Ber和50 nM EX-527的培养基进行干预。SI/R+PBS组为磷酸缓冲液(PBS)干预作为对照组。结果 与SI/R+PBS组相比,SI/R+Ber组Bcl-2的表达水平升高(P <0.001),Bax的表达水平显著降低(P <0.001),PGC-1α的表达水平明显升高(P <0.001);与SI/R+Ber组相比,SI/R+Ber+Ex-527组Bcl-2的表达水平降低(P <0.001),Bax的表达水平显著升高(P <0.001),PGC-1α的表达水平明显降低(P <0.001)。给予PGC-1α的抑制剂SR-18292后,与SI/R+Ber组相比,细胞活力显著降低(P <0.01);乳酸脱氢酶释放显著升高(P <0.001);MDA生成显著升高(P <0.01),大鼠心肌细胞的凋亡指数明显升高(P <0.01),ROS的产生明显升高(P <0.01),Bcl-2表达水平显著降低(P <0.001),Bax表达水平升高(P <0.01),SIRT1表达水平无明显变化(P> 0.05)。结论 Ber通过激活SIRT1/PGC-1α通路来减少ROS的产生,进而抑制SR/I损伤中的大鼠心肌细胞凋亡。

Objective To explore the molecular mechanism of Bergenin in alleviating ischemia-reperfusion(SI/R) injury in rat cardiomyocytes(H9C2).Methods H9C2 cells were modeled to simulate SI/R damage,the expression of key molecules was detected by WB,cell damage was detected by TUNEL staining and LDH release,intracellular reactive oxygen species levels were detected by DCFH-DA staining and MDA,and SIRT1 and PGC-1α were inhibited by EX-527 and SR-18292,respectively.The experimental groups were:the intervention group(SI/R+Ber),the intervention group(SI/R+Ber+EX-527),and the control group(SI/R+PBS).Results Compared with the SI/R+PBS group,the expression level of Bcl-2 in the SI/R+Ber group increased significantly(P < 0.001),the expression level of Bax decreased significantly(P < 0.001),and the expression level of PGC-1α increased significantly(P < 0.001).Compared with the SI/R+Ber group,the expression level of Bcl-2 in the SI/R+Ber+Ex-527 group decreased significantly(P < 0.001),the expression level of Bax increased significantly(P < 0.001),and the expression level of PGC-1α decreased significantly(P < 0.001).After administration of the inhibitor SR-18292 of PGC-1α,cell viability was significantly reduced compared with the SI/R+Ber group(P < 0.01),LDH release was significantly increased(P < 0.001),MDA production was significantly increased(P < 0.01),apoptosis index of cardiomyocytes was significantly increased(P < 0.01),ROS production was significantly increased(P < 0.01),Bcl-2 expression level was significantly decreased(P < 0.001),Bax expression level was increased significantly(P < 0.01),while SIRT1 expression level was not significantly changed(P > 0.05).Conclusion Bergenin activates SIRT1/PGC-1 α pathway to reduce ROS production,and then inhibit myocardial cell apoptosis in myocardial SI/R injury.