白藜芦醇和能量限制对大鼠肝脂肪变性影响

Resveratrol and calorie restriction improve hepatic steatosis in obese rats

目的探讨白藜芦醇(RSV)和能量限制(CR)对高脂高糖膳食诱导性肥胖大鼠肝脏脂肪变性作用。方法将40只SD大鼠随机分成模型组与对照组,分别以高脂高糖和基础饲料饲养8周,建立肥胖大鼠模型,8周末从模型组选出大于对照组平均体重+1.96倍标准差的肥胖大鼠随机分成肥胖组、白藜芦醇(250 mg/kg)及能量限制(60%/d)组,连续12周,于20周末观察大鼠肝脏脂肪变性改善状况。结果 20周末,肥胖组、白藜芦醇组、能量限制组和对照组大鼠平均体重分别为(759.30±16.75)、(689.30±8.55)、(586.10±11.35)和(598.00±9.8)g,肥胖组高于对照组(P<0.01),白藜芦醇、能量限制组均低于肥胖组(P<0.05);总能量摄入量以肥胖组最高,能量限制组最低;肥胖组、白藜芦醇组、能量限制组大鼠肝脏Sirt1、PGC-1αmRNA表达分别为[(0.42±0.04)、(0.79±0.16)、(0.88±0.06)]和[(0.67±0.19)、(1.26±0.34)、(2.35±0.37)],与肥胖组比较,白藜芦醇组、能量限制组大鼠肝脏Sirt1、PGC-1αmRNA表达升高(P<0.01);肥胖组大鼠肝细胞内脂质空泡大量蓄积,白藜芦醇、能量限制组大鼠肝脂肪变性均相对较轻。结论白藜芦醇可模拟能量限制作用,减少肝细胞脂肪变性,其机制可能与上调Sirt1和PGC-1α的mRNA表达、提高线粒体脂肪酸β氧化作用有关。

Objective To investigate the effect of resveratrol （RSV）and caloric restriction （CR）on hepatic steatosis in obese rats fed with high fat/sugar diet. Methods Forty Sprague-Dawley （SD）rats were randomly divided into a model and a control group and fed with high-fat/sugar and basic diet for 8 weeks. The obese rats with the average weight of 1.96 times standard deviation of the control group were picked out from the model group at the end of 8th week and then were randomly divided into obese, RSV （250 mg/kg） and CR （60%/d） groups. The improvements of hepatic steatosis of the rats were observed at the end of 20th week. Results At the end of 20th week, the mean body weight of rats in obese, RSV CR and control groups were 759. 30 ± 16. 75,689. 30 ± 8.55,586. 10 ± 11.35, and 598. 00 ± 9. 8 g, respectively, and the mean body weight of the obese group was higher than that of the control group （ P 〈 0. 01 ） and that of RSV and CR group were lower than that of the obese group （ P 〈 0. 05 ）. Total energy intake in obese group was the highest, and that of the CR group was the lowest. The liver silent information regulator 1 （ Sift1 ） ,peroxisome proliferator-activated receptor-coactivator 1α（FGC-1α）mRNA expression in obese,RSV,and CR groups were 0. 42 ±0. 04,0. 79 ±0. 16,0. 88 ±0. 06,and 0. 67 ± 0. 19,1.26 ±0. 34,2. 35 ±0. 37, respectively, and those in RSV and CR groups were higher than those of the obese group （P 〈0. 01 ）. The vacuolar accumulation was observed in liver cell of obese rats rats,and the rats in RSV and CR groups had relatively mild hepatic steatosis. Conclusion Resveratrol can simulate the energy restriction to reduce hepatic steatosis ,and the mechanism may be related to the increased Sirtl and PFC-1α mRNA expression and fatty acid β-oxidation function.