【摘要】 目的:观察外源性精胺对缺氧所致的乳鼠心肌细胞凋亡的影响,并探讨其机制。方法:复制原代培养乳鼠心肌细胞缺氧损伤模型(使用pH=6.8的Hank’s平衡盐溶液作为细胞培养基,排出氧气,然后在缺氧箱中培养24 h),细胞随机分为正常对照(Control)组、缺氧(Hypoxia)组和精胺干预(Hypoxia+Sp)组。Western blot检测心肌细胞多胺代谢关键酶(ODC、SSAT)蛋白质表达;CCK-8,Hoechst 33342染色观察细胞凋亡情况;光吸收法检测细胞(或培养液)内T-SOD和Caspase-3/-9活性,MDA、GSH含量;DCFH-DA染色观察细胞内活性氧(ROS)生成。结果:与正常组相比,Hypoxia组SSAT蛋白质表达、细胞凋亡率、MDA含量以及细胞内ROS生成增加,而ODC蛋白质表达、SOD活性、GSH含量降低;与Hypoxia组比较,Sp处理可减轻上述指标的变化。结论:外源性精胺可减轻缺氧引起的乳鼠心肌细胞损伤和凋亡,其机制与恢复多胺稳态和清除活性氧有关。更多还原

【Abstract】 Objective: To observe the effect of exogenous spermine on H/I-induced cardiomyocyte apoptosis in suckling rat,and to explore its mechanism. Methods: The hypoxia injury model was established on primarily cultured suckling rat cardiomyocytes( Hank’s balanced salt solution( pH = 6. 8) was used as cell culture medium,the oxygen in culturing environment was discharged,and the suckling rat cardiomyocytes were cultured in an anaerobic incubator for 24 hours). Cultured suckling rat cardiomyocytes were randomly assigned into control,hypoxia and hypoxia + spermine( Hypoxia + Sp) groups. The protein expressions of key enzyme catalyzing polyamine metabolism( ODC,SSAT) in cardiomyocytes were detected by Western blot. The cell apoptosis was detected by using Cell Counting Kit-8( CCK-8) and Hoechst 33342 dye. The activities of total-superoxide dismutase( SOD),caspase-3/-9 and the contents of malondialdehyde( MDA),glutathione( GSH) in cell medium were analyzed. Intracellular reactive oxygen species( ROS) generation was estimated by using DCFH-DA staining. Results: Compared with the control group,the expression of SSAT protein,apoptosis rate,MDA content,the activity of caspase-3/-9 and ROS generation were increased,but the expression of ODC protein,SOD activity and GSH content were decreased in hypoxia group. Compared with the hypoxia group,the changes of all index above-mentioned were weakened in the Hypoxia + Sp group. Conclusion: Exogenous spermine can attenuate cardiomyocyte injury and cell apoptosis of suckling rat induced by hypoxia,which mechanism is related with restoring polyamines homostasis and scavenging ROS.更多还原