L-肉碱对H2O2诱导氧化应激FHM细胞的影响

[目的] 本文旨在研究L-肉碱对氧化应激状态下胖头？i肌肉细胞系(fathead minnow muscle cell line,FHM)细胞活力、脂质过氧化及抗氧化功能的影响。[方法] 以FHM细胞为研究对象,以H2O2为氧化应激因子,采用四甲基偶氮唑盐(MTT)法测定不同浓度L-肉碱(0.001、0.01、0.1、0.5、1.0和5.0 mmol？L-1)预处理6 h分别对0.2和0.6 mmol？L-1 H2O2诱导的细胞氧化应激活力的影响,并采用生物化学方法检测L-肉碱预处理对氧化应激FHM细胞中脂质过氧化程度及抗氧化酶的变化。[结果] 0.2和0.6 mmol？L-1 H2O2刺激FHM细胞1 h,细胞活力分别降低至72%和58%。与H2O2组相比,0.001~1.0 mmol？L-1 L-肉碱预处理使低氧化水平(0.6 mmol？L-1 H2O2)的FHM细胞活力显著升高;且0.001、0.5和1.0 mmol？L-1 L-肉碱均显著降低不同氧化水平细胞中MDA含量。与0.2 mmol？L-1 H2O2组相比,0.001、0.01、0.1和1.0 mmol？L-1 L-肉碱显著提高细胞T-GSH含量;0.001、0.01和1.0 mmol？L-1 L-肉碱显著提高细胞中T-SOD活性;0.5~5.0 mmol？L-1 L-肉碱组细胞中CAT活性显著增加;添加0.001~1.0 mmol？L-1 L-肉碱显著提高细胞GPx活性,但γ-GCS活性只有0.5 mmol？L-1 L-肉碱组显著升高。与0.6 mmol？L-1 H2O2组相比,0.001~1.0 mmol？L-1 L-肉碱显著提高细胞中T-GSH含量,0.01~5.0 mmol？L-1 L-肉碱显著提高细胞中CAT活性,0.001 mmol？L-1 L-肉碱显著提高细胞T-SOD活性,0.01 mmol？L-1 L-肉碱显著提升细胞γ-GCS活性;同时,L-肉碱的处理显著增强细胞GPx活性。[结论] 高浓度(0.6 mmol？L-1)H2O2对FHM细胞的损害较大;0.001~1.0 mmol？L-1 L-肉碱可提高FHM细胞活力和抗氧化能力,并对细胞抵抗H2O2诱导的不同程度氧化应激有积极作用。
[Objectives] This study was designed to investigate the effects of L-carnitine on viability, lipid peroxidation and antioxidant function in fathead minnow muscle cell line(FHM)under oxidative stress.[Methods] Using FHM as study object and H2O2 as inducer of oxidative stress, the effects of defferent concentrations of L-carnitine(0.001, 0.01, 0.1, 0.5, 1.0 and 5.0 mmol？L-1) on cell viability following 0.2 and 0.6 mmol？L-1 H2O2 challenge were measured by methyl thiazolyl tetrazolium(MTT)method. The changes of lipid peroxidation and antioxidant enzymes in FHM cells were also detected by biochemical methods.[Results] Treatment with H2O2(0.2 and 0.6 mmol？L-1)for 6 h could decrease cell viability by 72% and 58%, respectively. Compared with H2O2 group, pre-treatment with L-carnitine at concentrations of 0.001-1.0 mmol？L-1 significantly inhibited lower level H2O2 (0.2 mmol？L-1)-induced cell viability loss, and MDA levels were significantly reduced in L-carnitine groups of 0.001, 0.5 and 1.0 mmol？L-1(P<0.05). Compared with 0.2 mmol？L-1 H2O2 group, L-carnitine(0.001, 0.01, 0.1 and 1.0 mmol？L-1)significantly increased intracellular T-GSH levels;the activities of T-SOD were significantly increased in L-carnitine groups of 0.001, 0.01 and 1.0 mmol？L-1, 0.5-5.0 mmol？L-1 L-carnitine significantly increased the CAT activities;adding 0.001-1.0 mmol？L-1 L-carnitine significantly increased the GPx activities;however, γ-GCS activity was reached significant level in 0.5 mmol？L-1 L-carnitine group. Compared with 0.6 mmol？L-1 H2O2 group, 0.001-1.0 mmol？L-1 L-carnitine significantly increased intracellular T-GSH levels;0.01-5.0