吉西他滨对肺微血管内皮细胞的损伤及表没食子儿茶素没食子酸酯的保护作用

目的 观察吉西他滨对大鼠肺微血管内皮细胞的影响及表没食子儿茶素没食子酸酯的保护作用。 方法 利用植块法分离大鼠肺微血管内皮细胞。SRB 法检测药物对肺微血管内皮细胞和 A549增殖的影响。流式细胞仪用于检测细胞周期和细胞凋亡。Western blot 法检测凋亡相关蛋白含量。测定细胞内活性氧和超氧化物歧化酶水平以及乳酸脱氢酶渗透情况。 结果 吉西他滨能显著减少肺微血管内皮细胞细胞增殖并将其阻滞于 S 期。吉西他滨引起肺微血管内皮细胞细胞凋亡具有时间依赖性，处理24、48、72 h 后细胞凋亡率分别为7.2%、15.4%、23.3%。同时，吉西他滨作用后细胞内活性氧含量上升，而处理48 h 后超氧化物歧化酶水平显著下降。进一步研究发现，表没食子儿茶素没食子酸酯能够提高吉西他滨处理后肺微血管内皮细胞的存活率，并且减弱吉西他滨造成的超氧化物歧化酶水平的下降。 结论 吉西他滨对肺微血管内皮细胞具有损伤作用，能够引起肺微血管内皮细胞的凋亡和氧化应激的发生，而表没食子儿茶素没食子酸酯对吉西他滨引起的肺微血管内皮细胞损伤具有保护作用。

Damage of gemcitabine towards pulmonary microvascular endothelial cells and protective effects of EGCG

Objective To investigate the damage of gemcitabine on rat pulmonary microvascular endothelial cells and the protective effect of EGCG. Methods PMVECs were isolated by modification of a tissue explant method. SRB assay was used to investigate the growth of PMVECs and A549 cells. Flow cytometry was applied to measure the cell cycle and apoptosis. Western blot was used to determine the content of apoptosis-related proteins. The activities of ROS, SOD and LDH were examined with microplate reader. Results The exposure to gemcitabine decreased the survival of PMVECs and arrested PMVECs at S phase. Gemcitabine increased the number of apoptotic cells time-dependently and the percentage of apoptotic cells treated for 24, 48, 72 h were 7.2%, 15.4%, 23.3%, respectively. Meanwhile, intracellular ROS level of PMVECs was elevated and after 48 h the SOD level was lowered markedly after gemcitabine treatment. Further investigation revealed that EGCG increased cell viability of PMVECs with or without gemcitabine and augmented the intracellular SOD level of PMVECs reduced by gemcitabine. Conclusion These results suggest that gemcitabine injures PMVECs by inducing pulmonary endothelial cell apoptosis and oxidative stress. EGCG exerts the protective effect on gemcitabine-induced endothelial cells injury.