儿茶素拮抗过氧化氢诱导的大鼠内皮祖细胞凋亡

Protective effects of catechin on apoptosis of endothelial progenitor cells induced by H2O2 in rats

摘要:

目的：观察过氧化氢（H2O2）对大鼠骨髓来源内皮祖细胞（EPCs）增殖及凋亡的影响及儿茶素对H2O2诱导细胞凋亡的的拮抗作用。方法：免疫荧光法检测EPCs表面标志CD34，CD133和血管内皮生长因子受体-2（VEGFR-2）的表达；将第2代EPCs分为空白对照组、H2O2组和儿茶素-H2O2组，干预后常规提取DNA琼脂糖电泳观察细胞凋亡梯带的形成；MTT法检测细胞增殖率的变化。结果：①骨髓单个核细胞培养10 d后均表达CD34，VEGFR-2和CD133抗原；②干预1 d后，3组细胞均未出现明显的DNA凋亡梯带；2 d后，H2O2组出现明显细胞凋亡DNA梯带；3 d后，H2O2组和儿茶素- H2O2组均出现明显的细胞凋亡DNA梯带，H2O2组凋亡DNA梯带数量、灰度强于儿茶素-H2O2干预组；③与对照组相比，H2O2组、H2O2-儿茶素组EPCs增殖活性明显下降（P<0.01）；在H2O2组和H2O2-儿茶素组组内EPCs增殖活性第1天和第3天细胞增殖活性明显高于第2天细胞增殖活性（均P<0.05）；H2O2组-儿茶素组细胞增殖活性在3个不同时间点显著高于同一时间点H2O2组细胞增殖活性。结论：H2O2可以降低EPCs增殖活性，诱导其凋亡；儿茶素可以增强EPCs对H2O2 的抵抗力，减少细胞凋亡。［中国当代儿科杂志，2009，11（1）：61-64］

Abstract:

OBJECTIVE: To study the effect of H2O2 on the proliferation and apoptosis of endothelial progenitor cells (EPCs) and the antogonistic effects of catechin on the cell apoptosis induced by H2O2 in rats. METHODS: Immuno-fluoreascence assay was applied to detect CD34, CD133 and VEGFR-2 expression. EPCs of generation 2 were divided into control cells, H2O2-treated cells and catechin-H2O2-treated cells (H2O2: 100 mg/L; catechin: 10 mg/L). Genomic DNA was extracted by the conventional method after intervention for the analysis of apoptosis ladder pattern. The MTT assay was applied to detect proliferation rate of EPCs. RESULTS: The cultured cells at day 10 expressed CD34, CD133 and VEGFR-2. DNA apoptosis ladder pattern appeared in H2O2 -treated cells 2 days after intervention. After 3 days of intervention DNA apoptosis ladder pattern appeared in both H2O2-treated cells and H2O2-catechin-treated cells, with more ladders and grayer scale in H2O2 -treated cells. Compared with the controls, H2O2-treated cells and H2O2-catechin-treated cells showed significantly decreased proliferation rate (P<0.01), with the lowest proliferation rate at the 2nd day (P<0.05). The H2O2-catechin-treated cells showed increased proliferation rate than H2O2-treated cells at the 1st, 2nd and 3rd days. CONCLUSIONS: H2O2 may impair EPCs proliferation and induce EPCs apoptosis. Catechin may increase the capacity of EPCs for the resistance to apoptosis induced by H2O2.［Chin J Contemp Pediatr, 2009, 11 (1):61-64］