油茶皂苷C对心肌细胞缺氧/复氧损伤的保护作用及其机制

目的 探讨油茶皂苷C（CS—c）预处理对培养乳鼠心肌细胞缺氧／复氧（A／R）损伤的保护作用及作用机制。方法 采用培养3—4d的SD大鼠心肌细胞,随机分为5组（每组8孔）：正常对照组,单纯缺影复氧组（A／R）,缺氧预适应组（AP）,油茶皂苷C预处理（CS—C）,格列苯脲预处理组（Glib）。采用心肌细胞缺氧／复氧损伤模型,各组于复氧1h时进行以下指标检测：（1）心肌细胞存活率;（2）培养液中乳酸脱氢酶（LDH）含量;（3）透射电镜观察心肌细胞超微结构改变。结果 与对照组比较,A／R组LDH含量（57．8U／L±6．4U／L）高于对照组（12．3U／L±1．7U／L）,差异有统计学意义（P〈0．01）,心肌细胞存活率（51．0％±1.9％）低于对照组（92．0％±2．0％）,差异有统计学意义（P〈0．01）,细胞超微结构损害明显;CS—C预处理组LDH含量（39．8U／L±3．9U／L）、心肌细胞存活率（76．4％±3．5％）低于A／R组（P〈0．01）,其结果与AP组（分别为32．4U／L±5．2U／L,78．0％±2．0％,P〉0．05）相似,Glib组LDH含量（55.8U／L±5．0U／L）高于CS—C预处理组、心肌细胞存活率（54．1％±3.7％）低于CS-C预处理组（P〈0．05）。结论 CS—C预处理抗乳鼠心肌细胞缺氧／复氧损伤作用与缺氧预适应作用相似,其保护作用可能与KATP^＋,通道开放有关。

Protection of camelliasaponin C against injury of myocardial cells by anoxia/reoxygenation and mechanism thereof

OBJECTIVE: To investigate the protective effects of camelliasaponin C (CS-C) pretreatment on myocardial cell injury induced by anoxia/reoxygenation. METHODS: Myocardial cells were obtained from neonatal SD rats, cultured for 3 to 4 days, added into the wells of a 24-well plate, and were divided randomly into five groups (8 wells for each group): control group, anoxia/reoxygenation (A/R) group, added with anoxia culture fluid for 3 h and then added with imitation reperfusion fluid for 1 h, anoxia preconditioning (AP) group, undergoing anoxia for 10 min before A/R, CS-C pretreated group, added with CS-C 3.75 x 10(-7) mol/L 1 h before A/R, and glibenclamide (Glib) pretreated group, added with CS-C 3.75 x 10(-7) mol/L and Glib 12 microm 1 h before A/R. Trypan blue exclusion was used to detect the viability of the cardiomyocytes, the contents of lactate dehydrogenase (LDH) in the supernatant of culture medium was measured. Electron microscopy was used to observe the ultrastructure of the cardiomyocytes. RESULTS: The contents of LDH of the A/R group was 57.8 U/L +/- 6.4 U/L, significantly higher than that of the control group (12.3 U/L +/- 1.7 U/L, P < 0.01), and the LDH value of the CS-C group was 39.8 U/L +/- 3.9 U/L, significantly lower than that of the A/R group (P < 0.01), not significantly different from that of the AP group (32.4 U/L +/- 5.2 U/L, P > 0.05), but significantly higher than that of the control group. The cardiomyocyte viability of the A/R group was 51.0% +/- 1.9%, significantly lower than that of the control group (92.0% +/- 2.0%, P < 0.01), the cardiomyocyte viability of the CS-C pretreatment group was 76.4% +/- 3.5%, significantly higher than that of the A/R group (P < 0.01), but not significantly different from that of the AP group (78.0% +/- 2.0%, P > 0.05). The cardiomyocyte ultrastructure of the A/R group was significantly changed, and the changes of cardiomyocyte ultrastructure in the CS-C pretreatment group were significantly attenuated compared with the A/R group. The content of LDH of the Glib group was 55.8 U/L +/- 5.0 U/L, significantly higher than that of the CS-C pretreatment group (P < 0.05), and the cardiomyocyte viability of the Glib group was 54.1% +/- 3.7%, significantly lower than that of the CS-C pretreatment group (P < 0.05), and the damage to the cardiomyocyte ultrastructure in the Glib group was more severe than in the CS-C group. CONCLUSION: The cardioprotective effect of CS-C pretreatment is similar to that of anoxia preconditioning and the effective mechanism would be related to the opening of ATP-sensitive K(+) channel. Glib can abolish the cardioprotective effect of CS-C pretreatment.