儿茶素对晚期糖基化终末产物诱导的内皮细胞凋亡的干预作用

目的探讨儿茶素对晚期糖基化终末产物（AGEs）诱导内皮细胞凋亡的干预作用。方法糖孵育法制备晚期糖基化终末产物，分离肾血管内皮细胞，将内皮细胞分成空白对照组、AGE组、浓度分别为10、15、20μg／ml的儿茶素组共五组。实验末，采用AlamarBlue还原法测定同内皮细胞增生活力，TUNEL法测定细胞凋亡率，生化法测定培养上清中·OH、MDA浓度，RT-PCR测定Bcl-2mRNA表达，Western-Blotting测定Bcl-2蛋白活性。结果与对照组相比，AGE组内皮细胞增生活性、Bcl-2基因与蛋白活性显著降低（P均〈0．01）；凋亡率、·OH与MDA浓度显著增加（P均〈0．01）；与AGE组相比，儿茶素各浓度组内皮细胞增生活力与Bcl-2基因与蛋白活性表达增高，凋亡率、·OH与MDA浓度降低；儿茶素各剂量组之间呈浓度梯度效应。结论儿茶素可降低AGEs引起的血管内皮细胞凋亡，其机制可能是通过有效清除活性氧自由基、上调Bcl-2mRNA与活性蛋白表达，阻断内皮细胞内过氧化物的堆积二种途径实现的。

Catechin Intervention on the Endothelial Cells Apoptosis Induced by Advanced Glycation End-products

Objective To exlpore the intervention of catechin on the endothelial cells apoptosis induced by advanced glycation end- products （AGEs）. Methods Glycose incubation assay was applied to prepare the AGEs, endothelial cells of glomeruli in SD rat were divided into five groups, control group, AGEs groups and eateehin groups, and catechin groups were comprised of 3 subgroups according to the its concentration, 10μg/L, 15μg/L and 20μg,/L; respectively. At the end of the experiments, AlamarBlue disoxidation was used to detect the proliferative activity of endothelial cells,TUNEL for the cellular apoptosis detectation, biochemistry assay for the ·OH and MDA measuring in the supernatant of the eultrue medium, and RT-PCR for the Bcl-2 mRNA expression examination. Western-Blotting for the Bcl-2 protein expression. Results Compared with the endothelial cells in control group, cells activity in AGEs groups presented a decreased proliferative activity, while Bcl-2 mRNA and protein expression and an augmented apoptosis rate （all P 〈0.01）,·OH and MDA concentration （all P 〈 0. 01 ）. Compared with the cells in AGEs group, cells in catechin groups showcd an increased proliferative activity and Bcl-2 mRNA, Bcl-2 protein expression and a decreased apoptosis rate （all P 〈 0.01 ） ,·OH and MDA concentration（ all P 〈 0. 01 ） ,with a dose-dependant pattern among the catechin groups. Conclusion Catechin could retard the endothelial Cells apoptosis induced by AGEs, probably due to the following mechanisms, cleaning the active oxygen free radicals and the upregulated expfession of Bcl-2.