低氧训练对营养肥胖型大鼠血清外泌体Wnt3a表达的影响

Effects of Hypoxic Exercise on the Expression of Serum Exosome Wnt3a in Obese Rats

目前,肥胖已被公认为一种全球性流行病,研究发现,训练可通过Wnt/β-catenin信号通路降低肥胖大鼠体质量并改善其脂代谢,且Wnt3a在其中发挥着重要的作用,但影响脂肪组织中Wnt3a表达的机制尚不清楚,研究旨在探讨不同环境下训练后营养肥胖型大鼠血清外泌体Wnt3a的表达变化以完善训练影响脂代谢的理论体系。按照随机分配原则将40只肥胖大鼠分为4组,每组10只:常氧训练组(CE)、常氧安静组(C)、低氧训练组(HE)、低氧安静组(H),进行4周干预训练。测量各组大鼠的体质量、肾周脂肪的质量以及体长;通过血脂生化检测盒来检测大鼠血清中低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)、胆固醇(total cholesterol,TC)以及甘油三酯(triglyceride,TG)的水平;分离血清外泌体并进行蛋白质组学分析。结果发现,低氧训练使肥胖大鼠体质量、脂体比、Lee′s指数、TC、TG和LDL-C降低(P<0.05),HDL-C升高(P<0.05);TEM电镜观察结果显示,C组、H组、CE组以及HE组均可以清晰地观察到外泌体胞外囊泡样结构,并在外泌体WB检测中均发现CD9、CD63和TSG101条带,WB检测结果发现,进行单纯低氧或单纯运动Wnt3a蛋白表达情况无显著性变化,低氧环境下Wnt3a蛋白表达水平显著提高。3种干预方式均可改善肥胖大鼠的血脂水平,低氧训练更为显著;低氧训练提升血清外泌体中Wnt3a含量。

Currently,obesity stands as a worldwide epidemic.Research has found that exercise training could effectively reduce body weight and enhances lipid metabolism in obese rats,with Wnt/β-catenin signaling pathway playing a pivotal role,especially Wnt3a.However,the mechanism underlying of influence Wnt3a in adipose tissue remains unclear.This study aimed to delve into the expression alterations of serum exosome Wnt3a in nutritionally obese rats following exercise training under varying hypoxic conditions,ultimately contributing to the theoretical framework of lipid metabolism modulated by hypoxic training.A total of forty obese rats were randomly assigned into four groups(n=10 each):normoxic exercise group(CE),normoxic quiet group(C),hypoxic exercise group(HE),and hypoxic quiet group(H).After a four-week hypoxic exercise intervention,the body weight,perirenal fat weight,and body length were recorded.The serum levels of low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),total cholesterol(TC),and triglyceride(TG)were determined using a lipid biochemical detection kit.Subsequently,serum exosomes were isolated and subjected to proteomic analysis.The findings revealed that hypoxic training significantly reduced body weight,fat-body ratio,Lee's index,TC,TG,and LDL-C levels(P<0.05),while increasing HDL-C(P<0.05)in obese rats.TEM electron microscopy distinctly depicted the extracellular vesicle-like structure of exosomes in groups C,H,CE,and HE,and WB detection of exosomes confirmed the presence of CD9,CD63 and TSG101 bands.Notably,the WB analysis showed no significant difference in Wnt3a protein expression between simple hypoxia and exercise alone.However,hypoxia significantly elevated Wnt3a protein expression.All three intervention methods contributed to improved blood lipid profiles in obese rats,with hypoxic training exhibiting a more profound effect.Consequently,hypoxic training increased the level of Wnt3a in serum exosomes.