杨梅酮对高脂诱导的肥胖小鼠脂肪肝的预防作用

Preventive Effects of Myricetin in Hepatic Steatosis of Obese Mice Induced by a High-Fat Diet

研究杨梅酮(Myricetin,MTN)对高脂诱导的肥胖小鼠脂肪肝的预防作用。32只C57BL/6J雄性小鼠随机分为4组:对照组(CT,饲喂正常日粮),对照+杨梅酮组(CT+MTN,饲喂含质量分数0.2%杨梅酮的正常日粮),高脂组(HF,饲喂高脂日粮),高脂+杨梅酮组(HF+MTN,饲喂含质量分数0.2%杨梅酮的高脂日粮)。10周后测定小鼠代谢差异(能量消耗、呼吸交换率、自主活动),血脂水平,肝脏氧化还原状态及脂质沉积情况,同时采用q PCR检测小鼠肝脏脂质代谢相关基因的表达。结果表明与对照组相比,长期高脂日粮导致小鼠体质量显著增加,内脏脂肪沉积,能量消耗显著降低(P<0.05)。肝脏发生氧化应激,表现为MDA显著上升,GSH-Px、SOD、CAT、GSH显著下降(P<0.05)。肝脏脂肪变性,肝脏甘油三酯(TG)、总胆固醇(TC)、游离脂肪酸(FFA)水平均显著高于对照组,脂质合成相关基因(Acc1、Fasn、Srebf1)显著上调,脂肪酸氧化相关基因(Cpt1α、Pparα)显著下调。高脂日粮基础上添加杨梅酮能够恢复肝脏TG、TC、FFA水平及肝脏脂质代谢相关基因(Acc1、Fasn、Srebf1、Cpt1α)的表达,同时维持肝脏的氧化还原状态。因此,推测杨梅酮可能通过维持肝脏氧化还原状态,促进能量消耗,调节肝脏脂质代谢,预防脂肪肝的发生。

To study the preventive effects ofmyricetin （MTN） on hepatic steatosis in mice induced by high-fat diets. Thirty-two male C57BL/6J mice were randomly divided into four groups ：control group （CT, fed a standard diet）, CT＋MTN group （fed a standard diet with additional 0.2% myricetin,w/w）,a high-fat diet group （HF）,HF＋MTN group （fed a high-fat diet with additional 0.2% myricetin, w/w）. When the mice were fed their respective diets for 10 weeks, metabolic differences （including energy expenditure,respiratory exchange ratio, and ambulatory activity）,plasma lipid profiles, hepatic redox status and lipid depositon were assessed. Furthermore ,the expression of genes that involved in lipid metabolism in liver was evaluated by qPCR analysis. The results showed that when compared to control group, HF group had a significantly higher body weight and lower energy expenditure （P〈0.05）. Oxidative stress occurred in liver as demonstrated by significantly elevated MDA levels,and remarkably decreased GSH-Px,SOD,CAT,and GSH levels. Meanwhile,hepatic steatosis was observed, hepatic TG, TC and FFA levels were significantly higher than control group, the expressions of lipogenesis-related genes （Accl,Fasn,and Srebfl） were significantly up-regulated,while the fatty acid oxidation related genes （Cptla and Ppara） were significantly down-regulated （P〈0.05）. myricetin that supplemented to high-fat diet could effectively normalize hepatic lipid status and lipid metabolism-related genes （Accl, Fasn ,Srebfl, and Cpt1α） expression, as well as improve oxidative stress related biomarkers. Therefore,myricetin prevented the occurrence of hepatic steatosis possibly through maintaining redox status,promoting energy expenditure, and regulating hepatic lipid metabolism.