甘氨酸对非乙醇性脂肪性肝病大鼠肝组织PPARα表达的影响

Effect of glycine on the expression of peroxisome proliferator-activated receptor α in the rat nonalcoholic fatty liver

目的:观察甘氨酸对非乙醇性脂肪性肝病大鼠肝组织过氧化物酶体增殖物激活受体α(PPARα)基因表达的影响。方法:采用20%玉米油饲料喂饲大鼠建立非乙醇性脂肪性肝病模型为对照组,甘氨酸组以20%甘氨酸液灌胃,每天1g。于第14周末检测动物脂质水平以及血浆内毒素、肿瘤坏死因子、游离脂肪酸含量,并做病理切片。以逆转录多聚酶链反应(RT-PCR)检测大鼠肝组织PPARαmRNA表达。结果:甘氨酸对非乙醇性脂肪性肝病大鼠PPARα基因表达有明显增强作用,同时肝内甘油三酯(TG)蓄积减少,肝细胞的损伤与炎症反应减轻。结论:甘氨酸可上调非乙醇性脂肪性肝病大鼠肝组织PPARα基因的表达,并显著地降低病鼠的内毒素水平,从而减轻病鼠的肝脂变与脂肪性肝炎的程度。

AIM： To observe the effect of glycine on the expression of peroxisome proliferator- activated receptor α （PPARα） in hepatic tissues of nonalcoholic fatty liver disease rats. METHODS： The nonalcoholic fatty liver disease （NAFLD） model of Wistar rats was established by feeding with 20% maize oil -containing diets. The animals were respectively fed with control diets and control diets plus glycine （Gly, 1 g/d, intragastric infusion at the same time）. The rats were sacrificed at 14 weeks, the concentrations of lipids, endotoxin, tumor necrosis factor -α, malondialdehyde, free fatty acid in plasma and hepatic tissues were determined. The hepatic pathological changes were observed, and hepatic tissues were collected to measure the expression of PPARα mRNA by the reverse transcriptase - polymerase chain reaction （ RT -PCR）. RESULTS： The expression of PPARα mRNA in the hepatic tissue was upregulated and the level of endotoxin decreased remarkably in Gly treatment group compared to the NAFLD group. Moreover, fatty liver and steatohepatitis showed improvement in Gly treatment group. CONCLUSION： Glycine upregulates the expression of PPARα mRNA in hepatic tissues and attenuates steatohepatitis.