大豆低聚肽对模拟失重大鼠肌萎缩的防护作用

目的观察大豆低聚肽对模拟失重条件下大鼠肌萎缩的对抗效果。方法尾部悬吊法建立模拟失重模型,SD雄性大鼠随机分为地面对照组(GC组)、尾吊对照组(TC组)及尾吊营养干预组,按大豆低聚肽低、中、高剂量0.03,0.1,0.3 g/ml,(S1、S2、S3),GC组和尾吊营养干预组经人工灌胃的方式分别给予对应剂量的纯净水和大豆低聚肽溶液,饲养4w后取血和比目鱼肌,按相关方法测定其相关各项指标。结果与GC组比较,TC组大鼠比目鱼肌(SOL)湿重和湿重体重比均显著减少(P<0.01),血清BUN、Ub水平显著升高(P<0.05),IGF-1、TESTO、SOD、GSH-Px水平显著降低(P<0.05),Atrogin-1蛋白表达水平增加32%。与TC组比较,营养干预组大鼠SOL的湿重和湿重体重比均显著增加(P<0.01);S1、S2组大鼠的IGF-1水平显著增加(P<0.05);S2、S3组血清SOD、GSH-Px活力水平均显著增加(P<0.05);Atrogin-1蛋白表达水平均减小,其中S3组差异显著(P<0.05)。结论 SOP可能通过刺激体内的合成代谢激素的分泌、提高体内抗氧化能力以及抑制Atrogin-1蛋白表达等机制,在一定程度上促进骨骼肌蛋白的合成,抑制骨骼肌蛋白的分解,从而减轻尾吊条件导致的肌萎缩。

THE PROTECTIVE EFFECTS OF SOY OLIGOPEPTIDE ON MUSCLE ATROPHY IN WEIGHTLESSNESS-SIMULATED RATS

Objective To investigate the protective effects of soy oligopeptide(SOP)on muscle atrophy in weightlessness-simulated rats.Method Weightlessness was simulated by tail-suspended model in rats.SD rats were randomly divided into 5 groups:ground control group(GC),tail-suspended control group(TC) and 3 tail-suspended nutrition intervention groups(NS,S1,S2,S3) according to the different doses of SOP(0.03,0.1,0.3 g/ml).They were fed normal diets and gived water or SOP solution by intragastric administration.The biochemical indices of serum and soleus(SOL) were measured after 4 w.Results Compared with GC group,the muscle wet weight(MWW) of SOL and the ratio of MWW to body weight in rats were significantly decreased(P<0.01).The level of blood urea nitrogen(BUN) and ubiquitin(Ub) in serum were significantly increased(P<0.05),while insulinlike growth fatory(IGF-1),testosterone(TESTO),SOD,GSH-Px in serum decreased(P<0.05).The expression of atrogin-1 protein in SOL was decreased by 32% in TC group.Compared with TC group,MWW of SOL and the ratio of MWW to body weight were significantly increased(P<0.01) in NS group.The level of SOD and GSH-Px increased significantly(P<0.05)in S2,S3 group as well as IGF-1 in serum in S1,S2 group,and the expression of atrogin-1 protein in SOL was decreased in all NS groups,but significantly in S3 group(P<0.05).Conclusion SOP may promote the synthesis and inhibit the breakdown of SOL protein to some extent to lessen SOL atrophy in tail-suspended rats.The possible mechanism was through stimulating the secretion of anabolic hormone and the antioxidate ability and inhibiting the expression of atrogin-1 protein.