葱白提取物对脂肪变性肝细胞PGC-1α表达及线粒体SDH活性的影响

摘要

目的 观察葱白提取物对脂肪变性肝细胞过氧化物酶体增殖物活化受体γ协同刺激因子1α(PGC-1α)表达及线粒体琥珀酸脱氢酶(SDH)活性的影响,探讨其防治脂肪肝的作用机制.方法 体外培养肝癌HepG2细胞用葱白提取物干顶24 h后,MTT法检测细胞活性.将细胞分为空白对照组(正常培养液)、模型组(脂肪乳干预)、葱白提取物组(脂肪乳及葱白共干预)和阴性对照组(脂肪乳及DMSO共干预),油红染色观察细胞内的脂滴形态及数量,生化技术检测细胞内TG含量,Western blot法检测细胞内PGC-1α蛋白的表达；分光光度法测定细胞上清液SDH活性,评价细胞线粒体代谢水平的变化.结果 葱白提取物对细胞活性无明显影响(P＞0.05).油红染色显示模型组细胞脂肪变性.与空白对照组比较,模型组细胞内TG含量增加、PGC-1α表达降低、SDH活性降低(P均＜0.05)；与模型组比较,葱白提取物组TG含量降低、SDH活性增加(P均＜0.05).结论 葱白提取物对脂肪变性肝细胞有明显的保护作用,其分子机制可能与上调PGC-1α基因的转录活性、增加线粒体SDH活性相关.%Objective To observe the effects of fistular onion stalk extract on the expression of peroxisome proliferatoractivated receptor-γcoactivator 1 α (PGC-1 α) and mitochondrial succinate dehydrogenase (MSDH) activity in fatty degeneration of liver cell model and to explore the possible molecular mechanism.Methods Hepatocellular carcinoma HepG2 cell line was cultured in vitro with fistular onion stalk extract intervention for 24 h,and cell viability was detected by MTT.Then the cells were divided into four groups:the control group,model group,fistular onion stalk extract group and negative control group.The intracellular lipid droplet morphology and quantity were observed by oil red staining; TG content was detected by biochemical technology; the expression of PGC-1 α protein in cells was detected by Western blot; SDH activity of cell supernatant was determined by spectrophotometry,and the change of mitochondrial metabolism was evaluated.Results The fistular onion stalk extract had no effect on the cell viability (P ＞ 0.05).Oil red staining showed fatty degeneration in the model group.Compared with the control group,TG content was significantly higher in the model group; the expression of intracellular PGC-1 α protein and SDH activity were decreased (all P ＜ 0.05).Compared with the model group,TG content was significantly lower and the activities of SDH were significantly increased in the fistular onion stalk group (all P ＜ 0.05).Conclusion Fistular onion stalk extract had significant protective effects on liver cells of steatosis,which may be related to the up-regulation of transcriptional activity of PGC-1α gene and the increase of SDH activities.