高住高练对肥胖大鼠肝脏SREBP-1c表达的影响

目的:探讨高住高练对高脂饮食肥胖大鼠肝脏SREBP-1c表达的影响。方法:出生21天离乳SD雄性大鼠280只,肥胖造模成功后挑选160只,2周适应性训练后筛选130只,随机分为13组:对照组(同时视为低住低练0周组、低氧安静0周组和高住高练0周组),低住低练1、2、3、4周组,低氧安静1、2、3、4周组,高住高练1、2、3、4周组。用水平动物跑台进行有氧耐力运动,低住低练各组在常氧下进行速度为26 m/min、1 h/d、6 d/w的运动,分别持续1～4周;低氧安静各组每天在低氧下(氧浓度为13.6%,约相当于3500 m海拔高度)生活,自由活动,不安排训练,分别持续1～4周;高住高练各组每天在低氧下(氧浓度为13.6%)生活23 h,训练1 h,速度为21 m/min,6 d/w,分别持续1～4周(非训练日生活24 h)。对照组于正式实验开始前、安静组于相应周数后、运动组于最后一次训练后恢复24 h取材。分别采用实时荧光定量PCR技术和Western Blot技术检测大鼠肝脏SREBP-1c基因和蛋白表达。结果:相同训练模式不同周数之间比较,高住高练组大鼠肝脏SREBP-1c mRNA和蛋白表达在第1、2、4周较对照组均变化无统计学意义(P>0.05),第3周mRNA表达降低,与对照组比较差异有统计学意义(P<0.05),第3周蛋白表达下降,与1、2周组之间的差异均有统计学意义(P<0.05)。相同周数不同训练模式之间比较,第1、4周,高住高练组肝脏SREBP-1cmRNA和蛋白表达与低住低练组和低氧安静组比较差异无统计学意义(P>0.05),第2周高住高练组SREBP-1c蛋白表达高于低住低练组(P<0.01),第3周高住高练组SREBP-1c mRNA和蛋白表达低于低氧安静组(P<0.05)。结论:3周高住高练抑制肥胖大鼠肝脏SREBP-1c mRNA和蛋白表达效果较好。

Living High Training High Inhibits the SREBP-1c Expression in Obese Rats Liver

Objective The purpose of this research is to investigate the effect of living high training high on SREBP-1c expression in obese rat liver.Methods One hundred and thirty 21-day-old SD male obese rats induced by high fat diet were divided into 13 groups randomly:0-week control group(same as 0-week living low training low group,0-week hypoxic control group,and 0-week living high training high group);1-,2-,3-,and 4-week living low training low groups;1-,2-,3-,and 4-week hypoxic control groups;and 1-,2-,3-,and 4-week living high training high groups.Aerobic training of animals in living low training low groups were performed on a treadmill at the speed of 26 m/min with 0 slope,1 hour per day,6 days per week,for 1,2,3,and 4 weeks respectively.Hypoxic control groups lived in a chamber with oxygen concentration of 13.6%(equivalent to 3500 m altitude) without training for 1,2,3,and 4 weeks respectively.Living high training high groups lived in hypoxic environment same as the control groups,23 hours per day,and exercised on the treadmill at 21 m/min,1 hour each day,6 days per week,for 1,2,3,and 4 weeks respectively.The livers of rats in control group were removed at beginning of experiment,and in training groups at the corresponding week 24 hours after the last training.SREBP-1c mRNA expression and protein expression were measured respectively by real-time fluorescence quantitative PCR and Western blot.Results As compared the different training durations in the same training mode,SREBP-1c mRNA and protein expressions only in 3-week living high training high group significantly lower than the control group,as well as than that in 1-and 2-week living high training high group(P < 0.05).As compared the different training modes in the same training duration,SREBP-1c mRNA and protein expressions in 2-week living high training high group were higher than that in 2-week living low training low group(P < 0.01);and in 3-week living high training high group were lower than that in control group(P < 0.05).Conclusion 3-week living high training high could better inhibit SREBP-1c mRNA and protein expressions in the liver of obese rats.