尿酸在氧化应激状态下对人脐静脉内皮细胞的影响

目的 探讨不同浓度尿酸(UA)、作用不同时间及其在氧化应激状态下对人脐静脉内皮细胞(HUVEC)的影响.方法 体外细胞培养,用不同浓度UA(0 mg/d L、4 mg/d L、8 mg/d L、12 mg/d L)、过氧化氢(H2O2)(0.5 mmol/L)及不同浓度UA+H2O2刺激HUVEC.分别于24 h、48 h后观察HUVEC的细胞形态,采用MTT法检测HUVEC的增殖情况,用ELISA方法检测培养液中一氧化氮(NO)、内皮素-1(ET-1)的浓度.结果实验发现4 mg/d L UA组HUVEC 24 h、48 h后活力较对照组差异无统计学意义(P>0.05);8 mg/d L、16mg/d L组24 h后HUVEC活力较对照组差异无统计学意义(P>0.05),48 h后8 mg/d L、16 mg/d L组HUVEC活力较对照组显著降低(P<0.05).H2O2组HUVEC活力较对照组有显著降低(P<0.05);各种浓度UA加H2O2组HUVEC 24 h后较单纯H2O2组活力强,而48 h后8 mg/d L加H2O2、16 mg/d L加H2O2组较单纯H2O2组活力差异无统计学意义(P>0.05).ELISA法检测发现48 h后16 mg/d L UA组较对照组细胞合成NO减少,分泌ET-1增多(P<0.05).8 mg/d L加H2O2、16 mg/d L加H2O2组与单纯H2O2组相比,24 h后细胞合成NO增多,分泌ET-1减少(P<0.05);而48 h后16 mg/d L加H2O2组与单纯H2O2组相比,细胞合成NO减少,分泌ET-1增多(P<0.05).结论 尿酸对HUVEC的作用不仅与浓度有关,与作用时间也有关系.急性升高的尿酸对HUVEC还有保护作用,而高浓度的尿酸长时间对HUVEC有损伤作用,而氧化应激可能加重尿酸对HUVEC的损伤作用.

Influence of Uric Acid on Human Umbillical Vein Endothelial Cells under Oxidative Stress

Objective To investigate the effects of uric acid(UA) and UA under oxidative stress on cultured human umbillical vein endothelial cells(HUVEC).Methods HUVECs were incubated with different concentration UA(0,4,8,16 mg/d L),H2O2(500 mmol/l) and UA+H2O2(500 mmol/l) for 24,48 and 72 hours.Then we observed the morphology of HUVECs and evaluated the proliferation of HUVECs by MTT assay.NO and ET-1 in supernatant medium was detected by ELISA.Results For the viability of HUVECs,there was no statistically significant difference between 4 mg/d L UA group and control group after incubation for 24,48 and 72hours(P>0.05) and between UA groups(8 mg/d L and 12 mg/d L) and control group after incubation for 24, 48 and72 hours(P>0.05).After incubation with 12 mg/d L of UA for 48 hours or 8 mg/d L of UA for 72 hours,the viability of HUVECs decreased significantly(P <0.05) The viability of HUVECs in H2O2 group decreased significantly(P<0.05).The viability of HUVECs in UA+H2O2groups after incubation for 24 h was significantly better than H2O2 group.There was no signifiant difference in the cell viability between(8 mg/d L or 12 mg/d L)UA+H2O2group and H2O2 group. Compared with the control group, the NO levels were decreased and the ET-1 levels were increased in the supernatants of HUVECs in 12 mg/d L UA group for 72 hours(P<0.05). Compared with H2O2 group,the NO levels were increased and the ET-1 levels were decreased in the supernatants of HUVECs in(8mg/d L or 12 mg/d L) UA +H2O2groups for 24 hours(P<0.05),while for(12 mg/d L) UA +H2O2group for 72 hours, the results were just the contary.Conclusion The effects of UA on HUVECs are related with both concentration and action time.Acutely increased UA may protect HUVECs form injury,while long action of UA may injure HUVECs,especially under oxidative stress.