尿酸盐致血管内皮细胞损伤的机制

目的观察不同浓度尿酸盐对人血管内皮细胞损伤相关因子表达的影响，明确高尿酸血症对人血管内皮细胞的损伤的机制。方法体外单独培养人血管内皮细胞或与单核细胞共培养，尿酸盐分别用6．6mg／dl（约为人体男、女高尿酸血症最低值平均值）及该值2、3、4、5倍值刺激血管内皮细胞48小时，用酶联免疫吸附双抗体夹心法（ELISA）测定上清液白细胞介素1（IL-1）、肿瘤坏死因子α（TNF-d）、细胞间粘附分子-1（ICAM-1）、血浆纤溶酶原激活抑制剂-1（PAI-1）等因子表达水平，用逆转录-聚合酶链式反应（RT-PcR）测定血管内皮细胞人尿酸盐转运子（hUAT）mRNA的表达。结果①不同浓度尿酸盐与血管内皮细胞单独培养：结果显示高浓度尿酸盐使血管内皮细胞IL-l、TNF-Ⅸ、ICAM-1、PAI-1的表达上调，明显高于对照组（P均〈0．05）；②不同浓度尿酸盐与血管内皮细胞及单核细胞共培养：结果显示高浓度尿酸盐使血管内皮细胞IL-1、TNF-α、ICAM-1、PAI-1的表达进一步增高，明显高于对照组（P均〈0．05）；③hUATmRNA表达：高浓度尿酸盐使血管内皮细胞hUATmRNA表达明显低于对照组（P〈0．05）；与单核细胞共培养高浓度尿酸盐使血管内皮细胞hUATmRNA表达明显进一步下调（P〈0．05）。结论尿酸盐可以作为独立的危险因素引起内皮细胞的直接损伤，单核细胞在内皮细胞损伤过程中亦起到了重要作用，血管内皮细胞和单核细胞共培养使血管内皮细胞损伤进一步加重。

The mechanism of vascular endothelial cell damage by urate

Objective To observe the role of different concentration of urate in the expression of vascular endothelial cell injury associated factors;To identify the mechanism of injury of hyperuricemia on vascular endothelial cells.Methods All experiments were performed with human vascular endothelial cells cultured and endothelial cells and monocytes co-cultured in vitro.As stimulations,the concentration of urate in culture medium were 6.6mg/dl(which was the minimum of average uric acid in human),and double,triple,four times,five times of this concentration,respectively.Different concentrations of urate were used to stimulate vascular endothelial cells for 48 hours.The levels of IL-1、TNF-α、ICAM-1 and PAI-1 in the supernatants of cell cultures were measured by enzyme linked immunosorbent assay(ELISA).Meanwhile,the expression of hUAT (human urate transporer) mRNA was tested by using RT-PCR.Results ①different concentration of urate cultured with vascular endothelial cells:the expressions of IL-1、 TNF-α、ICAM-1 and PAI-1 significantly increased in high concentration of urate groups compared with the control group(P<0.05);②different concentration of urate co-cultured with vascular endothelial cells and monocytes:the expressions of IL-1、TNF-α 、ICAM-1 and PAI-1 were progressively increased in high concentration of urate groups,significantly higher than the control group(P<0.05);③the expression of hUAT mRNA in high concentration of urate group was significantly lower than that of the control group(P<0.05),while it significantly progressively decreased in co-cultured groups(P<0.05).Conclusions Urate can cause direct injury on endothelial cells as an independent risk factor,mononuclear cells also play an important role in the process of endothelial cell injury,and endothelial cells and monocytes co-cultured cause more progressive injury on endothelial cells.