瘦素在诱导血管内皮细胞纤溶酶原激活物抑制物-1表达中的作用

摘要

Objective To investigate in vitro the effect of human leptin on the expression of plasminogen activator inhibitor type 1 (PAI-1) in vascular endothelial cells (VEC). Methods Human umbilical vein endothclial cells (HUVECs) were isolated and subcultured by enzymatic disaggrcgation in the presence of human recombinant leptin at different times. Real-time PCR, Northem blot and Western blot were used to detect mRXA and protein expression of PAI-1. Results Under the condition of 100 ng/ml leptin, the expression levels of PAI-1 mRXA increased as the time increased in general, and reach the peak at 8 h point. The levels of tPA showed no significant changes as the time increased. The levels of PAI-1 mRXA increased as the concentration of leptin increased, while those of tPA mRXA showed no significant difference. Human leptin induced the expression of PAI-1 mRXA and protein in HUVECs in time-and dose-dependent manner. Conclusion Human leptin upregulated PAI-1 expression. Thus, chronic oxidative stress in endothelial cells under hyperleptinemia may activate artherothrombosis processes and contribute to the development of vascular pathology.%目的 通过体外研究探讨瘦素对血管内皮细胞纤溶酶原激活物抑制物-1表达的影响.方法 Ⅱ型胶原酶消化法分离和培养人脐静脉内皮细胞(HUVECs),在不同时间采用不同剂量瘦素培养HUVECs,应用荧光定量PCR、Northern blot以及Western blot检测技术研究瘦素对HUVECs PAI-1 mRNA及蛋白表达的影响.结果 100 ng/ml瘦素作用于内皮细胞,PAI-1 mRNA表达水平随着时间延长呈升高的趋势,8h达到最高(P＜0.001),24 h后仍高于起点(P＜0.005),而tPA的表达则无显著变化(P＞0.05).不同浓度的瘦素作用于内皮细胞,其PAI-1mRNA水平呈剂量依赖性升高(P＜0.001)；tPA mRNA表达亦无显著变化(P＞0.05).100 ng/ml瘦素孵育HUVECs时间依赖性促进PAI-1蛋白表达,24h达到最高峰.结论 瘦素可能通过诱导血管内皮细胞PAI-1表达促进动脉粥样硬化和血栓的形成.