基于AMPK/PGC-1α信号通路探讨菟丝子多糖改善大鼠运动能力的作用及机制

Effects and Mechanism of Cuscuta chinensis Polysaccharides on Improving Motor Ability in Rats Based on AMPK/PGC-1αSignaling Pathway

【目的】基于腺苷酸活化蛋白激酶(AMPK)/过氧化物酶体增殖活化受体γ共激活因子1α(PGC-1α)信号通路探讨菟丝子多糖改善大鼠运动能力的作用及潜在机制。【方法】将大鼠50只分为正常对照组、运动模型组及菟丝子多糖低、中、高剂量组(10、200和400 mg/kg),除正常对照组外,其余各组大鼠进行游泳训练。游泳至力竭后,测定各组大鼠血清抗疲劳指标以及肝组织能量代谢和氧化应激指标,AMPKα和PGC-1αmRNA的表达水平,磷酸化AMPKα(p-AMPKα)、AMPKα和PGC-1α的蛋白表达水平。【结果】与运动模型组相比,菟丝子多糖低、中、高剂量组大鼠游泳力竭时间显著或极显著延长,血清尿素氮、乳酸、皮质酮以及肝组织丙二醛含量极显著减少,血清睾酮以及肝组织糖原、钠钾ATP酶、钙镁ATP酶、超氧化物歧化酶、谷胱甘肽过氧化物酶水平显著增加,肝组织AMPKαmRNA及其蛋白表达无明显变化,PGC-1αmRNA及p-AMPKα、PGC-1α蛋白表达极显著增加。【结论】菟丝子多糖可提升高强度大运动量训练大鼠的运动能力,且该作用与抗疲劳、增加能量物质储备、抑制氧化应激及活化AMPK/PGC-1α信号通路等有关。

[Purpose]To study the effects and potential mechanism of Cuscuta chinensis polysaccharides(CCPs)on improving motor ability in rats,based on adenosine monophosphate activated protein kinase(AMPK)/peroxisome proliferator activator receptorγcoactivator 1α(PGC-1α)signaling pathway.[Methods]Fifty rats were divided into normal control(NC)group,exercise model(EM)group and CCPs low-dose(CCPs-L),medium-dose(CCPs-M)and high-dose(CCPs-H)groups(10,200 and 400 mg/kg).Except NC group,all rats in the other groups needed swimming training.After ltural University(Natural Science)E-mail:ynauzkxb@foxmail.com swimming to exhaustion,the anti-fatigue indexes in serum,the indexes of energy metabolism and oxidative stress in liver tissue,the mRNA expression levels of AMPKαand PGC-1α,and the protein expression levels of phosphorylated AMPKα(p-AMPKα),AMPKαand PGC-1αwere measured.[Results]Compared with EM group,swimming exhaustion time of CCPs groups was significantly or extremely significantly prolonged;the contents of blood urea nitrogen,lactic acid and corticosterone in serum and malondialdehyde in liver tissue were extremely significantly decreased;the contents of serum testosterone and liver glycogen,and the activities of Na+-K+-ATPase,Ca^(^(2+))-Mg^(^(2+))-ATPase,superoxide dismutase and glutathion peroxidase in liver tissue were significantly increased;the mRNA and protein levels of AMPKαin liver tissue had no significant changes,but the mRNA level of PGC-1αand protein levels of p-AMPKαand PGC-1αwere extremely significantly increased.[Conclusion]CCPs can improve the exercise ability of rats trained with high intensity,which is related to anti-fatigue,increasing energy reserves,inhibiting oxidative stress and activating AMPK/PGC-1αsignaling pathway.