牡蛎糖胺聚糖对损伤的血管内皮细胞功能的影响

采用人脐静脉内皮细胞株ECV304体外培养的方法,复制过氧化氢(H2O2终浓度为50μg/ml)诱导的血管内皮细胞氧化损伤模型,应用硝酸还原酶法检测一氧化氮(NO)的含量,采用化学比色法分别检测谷胱甘肽过氧化物酶(GSH-PX)活性、总抗氧化能力(T-AOC)、总一氧化氮合酶(T-NOS)和诱导型一氧化氮合酶(iNOS)的活性。结果显示,与正常对照组相比,过氧化氢损伤的血管内皮细胞其GSH-PX活性、T-AOC、NO含量及T-NOS活性均明显降低(P<0.01),iNOS活性明显增加(P<0.01)。与损伤模型组相比,O-GAG各浓度保护组(50、100和200μg/ml)细胞的GSH-PX活性、T-AOC、NO含量及T-NOS活性均明显升高(P<0.01),而iNOS活性则显著降低(P<0.01)。表明牡蛎糖胺聚糖可以提高受损血管内皮细胞的抗氧化能力以及合成释放NO的功能,对H2O2诱导的血管内皮细胞氧化损伤有保护作用。

Influences of oyster glycosaminoglycan on the functions of injured vascular endothelial cells

This study aimed at investigating the influences of oyster glycosaminoglycan(O-GAG) on the function of injured human vascular endothelial cell (VECs). The endothelial cell strain of human umbilical vein ECV304 was incubated in vitro and a model of VECs injured by hydrogen peroxide (H2O2) was established. The secretion of nitric oxide (NO) was measured with nitrate reductase method. By using chemical colorimetry, the activities of glutathione peroxidase (GSH-PX) and total antioxidative capacity(T-AOC), the intracellular activities of total nitric oxide synthase (T-NOS) and inducible nitric oxide synthase(iNOS)were determined. The results indicated that the activities of GSH-PX and T-NOS, T-AOC and the content of NO in vascular endothelial cells injured by hydrogen peroxide decreased significantly (P<0.01), whereas the activities of iNOS increased significantly (P<0.01), compared to the control group. Compared to the injured model group, however, the activities of GSH-PX and T- NOS, T-AOC and the secretion of NO in the groups with different dose of O-GAG increased significantly (P<0.01), and the activities of iNOS decreased remarkably (P<0.01). It is concluded that O-GAG can enhance the antioxidant capacity of VECs, promote secretion of NO, and have protection effect on VECs injured by H2O2.