菊苣酸对蛋白质氧化损伤的作用

Effect of Chicoric Acid on Oxidative Protein Damage

目的:评价菊苣酸对自由基诱导蛋白质氧化损伤的影响。方法:采用Cu^(2+)/H_2O_2和2,2’-偶氮二(2-甲基丙基咪)二盐酸盐(2,2’-azobis(2-methylpropionamidine)dihydrochloride,AAPH)两种不同的自由基诱导体系,分别诱导牛血清白蛋白(bovine serum albumin,BSA)、小鼠肝脏蛋白和脑蛋白氧化损伤,研究菊苣酸对蛋白氧化损伤的影响;通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和蛋白免疫印迹法检测蛋白氧化损伤程度。结果:菊苣酸在100~1 000μmol/L浓度范围内能够抑制Cu^(2+)/H_2O_2诱导的BSA氧化损伤;低浓度菊苣酸对Cu^(2+)/H_2O_2诱导的小鼠肝脏蛋白和脑蛋白氧化损伤具有保护作用,但在高浓度时表现出促氧化作用;在AAPH诱导体系中,菊苣酸对3种蛋白模型均具有保护作用,且菊苣酸浓度越高保护效果越好。结论:在Cu^(2+)/H_2O_2和AAPH两种诱导体系中,菊苣酸对蛋白质氧化损伤表现出不同的作用效果。

The effect of chicoric acid on free radical-induced oxidative damage to proteins was evaluated in this paper.Two different paradigms including metal-catalyzed oxidation induced by Cu2+/H2O2 and alkylperoxyl radicals formed by azo initiator 2,2’-azobis(2-amidinopropane)hydrochloride(AAPH)were used to induce oxidative damage to proteins including bovine serum albumin(BSA)and mouse liver and brain proteins.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot were applied to determine the level of oxidative protein damage.Results showed that chicoric acid in the range of 100–1 000μmol/L significantly inhibited oxidative protein damage induced by Cu2+/H2O2.However,chicoric acid at high concentration could induce oxidative damage to mouse tissue proteins.Chicoric acid protected the proteins against oxidative damage induced by AAPH-derived alkylperoxyl radicals in a dose-dependent manner.In conclusion,chicoric acid has different protective effects on oxidative protein damage in both paradigms.