异丙酚对第三丁基过氧化氢诱导的心肌细胞凋亡的保护作用

Protective effect of propofol on tert-butyl hydroperoxide-induced apoptosis in cultured rat cardiomyocytes

目的观察异丙酚对第三丁基过氧化氢(t-BHP)诱导的心肌细胞凋亡的影响并探讨可能的机制。方法采用SD新生大鼠进行心肌细胞原代培养。实验分为5组:正常对照组、t-BHP组和异丙酚1、10、30μmol.L-1组。分光光度计法检测细胞内谷胱甘肽(GSH)、丙二醛(MDA)水平和超氧化物岐化酶(SOD)活性;四甲基偶氮唑盐比色法(MTT)检测细胞线粒体活性,罗丹明123(Rhodamine123)荧光染色、流式细胞仪检测细胞线粒体膜电位(ΔΨm),流式细胞术(FCM)测定细胞凋亡率,Western blot法检测caspase-3的表达。结果与正常对照组相比,100μmol.L-1的t-BHP处理心肌细胞4 h后,细胞内GSH水平明显下降(P<0.05),MDA含量增加(P<0.01),抗氧化酶SOD活性降低(P<0.01),细胞线粒体活性降低(P<0.01),线粒体膜电位ΔΨm明显下降(P<0.01),细胞凋亡率和caspase-3的表达明显升高(P<0.01);异丙酚10、30μmol.L-1能减少过氧化氢所致的细胞中MDA含量升高;提高SOD活性和GSH水平;提高线粒体活性、膜电位;抑制心肌细胞凋亡和caspase-3的表达升高(P(0.05,P(0.01)。结论异丙酚能减弱过氧化氢所致的心肌细胞凋亡,其作用机制可能是通过减少活性氧自由基导致的细胞膜氧化损伤、提高线粒体活性、维持线粒体的膜电位,从而抑制心肌细胞凋亡的发生。

Aim To investigate the protective effects of propofol against tert-butyl hydroperoxide （t-BHP）-induced oxidative injury in cultured rat cardiomyoeytes and the possible mechanism. Methods Primary cultured neonatal rat cardiomyocytes was performed. Cultured cardiomyocytes were divided into five groups： control group, t-BHP group, and propofol 1, 10, 30μmol·L^-1 group. Cellular Superoxide dismutase （ SOD ） activity, glutathione （ GSH ） and malonaldehyde （MDA） content were measured by colorimetric assay. Mitochondrial activity was determined by methylthiazolyl tetrazolium （MTT） test. The mitochondrial membrane potential （ΔΨm） was analyzed by Rhodamine123 staining and flow cytometry. The apoptosis of cardiomyocytes was detected by flow cytometry（FCM）. The expression of caspase-3 was determined by Western blot. Results Compared with the control group, the MDA content significantly increased in t-BHP-treated group （P 〈 0. 01 ）. The activity of SOD, GSH content significantly decreased （ P 〈 0. 0 1 ） . The mito -chondial activity and mitochondria membrane potential （ΔΨm） decreased （ P 〈 0. 05 ）. The apoptotic rate and the expression of caspase-3 were significantly high- er than those of control group （P 〈 0. 01 ）. Compared with t-BHP-treated group, 10, 30μmol·L^-1 propofol could significantly decrease the content of MDA, increase the activity of SOD and the content of GSH, enhance activity of mitochondria and ΔΨm, and reduce the expression of caspase-3 and the rate of apoptosis （P 〈 0.05 ）. Conclusions Propofol attenuates apoptosis induced by hydrogen peroxide in neonatal rat cardiomyocytes. The underlying mechanism might be attributed to attenuating the oxidant injury in membrane, stabilizing the mitochondrial membrane potential, maintaining the mitochondria function and thus inhibiting the occurrence of cardiomyocyte apoptosis.