牡蛎糖胺聚糖对血管内皮细胞损伤的保护作用研究

Study in the protection effects of oyster glycosaminoglycan on vascular endothelial cell injury

目的：探讨牡蛎糖胺聚糖(O-GAG)对血管内皮细胞损伤的保护作用,观察它对损伤的血管内皮细胞内一氧化氮(NO)、丙二醛(MDA)含量及乳酸脱氢酶(LDH)活性的影响。方法：采用人脐静脉内皮细胞株ECV304体外培养的方法,建立过氧化氢(H_2O_2)诱导的内皮细胞损伤模型,噻唑蓝(MTT)比色法观察牡蛎糖胺聚糖对血管内皮细胞增殖活性的影响,硝酸还原酶法、硫代巴比妥酸法和硝基苯肼法分别检测细胞内NO的含量、细胞培养液内MDA的含量和LDH的活性。结果：模型组较正常对照组细胞增殖活性明显降低(P＜0．01)。与模型组相比,经牡蛎糖胺聚糖预处理的各保护组(除10μg/ml)细胞增殖活性明显增加(P＜0．05,P＜0．01),NO的含量增加,MDA的含量和LDH的活性降低(P＜0．01)。牡蛎糖胺聚糖(100、200μg/ml)对于正常的内皮细胞有促增殖作用(P＜0．05)。结论：牡蛎糖胺聚糖对氧化损伤的血管内皮细胞具有保护作用,其作用机制可能与增加细胞NO含量、减少MDA生成和LDH释放有关。牡蛎糖胺聚糖对正常血管内皮细胞在一定剂量范围内有促增殖作用。

Objective： To evaluate the protective action of oyster glycosaminoglycan （O-GAG） on the injured vascular endothelial cells （VECs）, and investigate the effects of O- GAG on the expression of Nitric Oxide （NO）, Maleic Dialdehyde（MDA）, Lactate Dehydrogenase （LDH） in human VECs. Methods： The endothelial cell strain of human umbilical vein was cultured in vitro, and a model of VECs injured by hydrogen peroxide （H2O2） was established. The influence of O-GAG on the proliferative activity of VECs was observed by means of MTT assay. The levels of NO, MDA and LDH in culture medium were measured. Results： Compared with the normal control group, the proliferative activity of VECs in model group remarkably decreased （P〈 0.01 ）, while in each protective group pretreated by O - GAG （except 10μg/ml）, the proliferative activity of VECs obviously inereased（P 〈 0.05, P 〈 0.01）. O - GAG could increase the level of NO and decreased the levels of MDA and LDH in a concentration- dependent manner （P〈 0.01）. The O- GAG control groups （100μg/ml,200μg/ml） could increase the proliferative activity of normal VECs（ P 〈 0.05）. Conclusion： O- GAG can protect the VECs from H2O2 - induced injury. The mechanism may be related with the increase of NO levels and decrease of MDA generation and LDH release. O - GAG can proliferate the normal VFCs in a certain dosage.