红景天苷对运动性疲劳大鼠糖脂代谢和氧化应激的影响

Effects of Salidroside on Glucose and Lipid Metabolism and Oxidative Stress in Exercise-induced Fatigue Rats

本研究旨在揭示红景天苷(salidroside,SAL)对运动性疲劳(EIF)大鼠糖脂代谢和氧化应激的影响。将大鼠随机分成5组,每组12只。处理组大鼠分别灌胃50、100和200 mg·kg^(-1)·d^(-1)的红景天苷,CON组和EIF组灌胃生理盐水,共给药9周。灌胃2 h后,CON组大鼠不运动,其他组大鼠进行递增负荷游泳运动。检测了大鼠的血清心肌损伤指标[乳酸脱氢酶(LDH),肌酸激酶(CK)和心肌肌钙蛋白I(cTnI)]、糖脂代谢指标[肝/肌糖原,葡萄糖(Glu),乳酸(LA),尿素氮(BUN)和游离脂肪酸(NEFA)]和骨骼肌氧化应激指标[超氧化物歧化酶(SOD),过氧化氢酶(CAT)和丙二醛(MDA)]水平。通过RT-qPCR检测骨骼肌组织过氧化物酶体增殖物激活受体γ共激活因子α(PGC-1α)、己糖激酶2(HK2)、葡萄糖转运蛋白-4(GLUT-4)、单羧酸转运蛋白1(MCT-1)、血红素加氧酶1(HO-1)、NAD(P)H:醌氧化还原酶-1(NQO-1)m RNA水平。通过Western blot检测骨骼肌组织中AMP激活的蛋白激酶α(AMPKα)的磷酸化水平以及细胞核核因子E2相关因子2(Nrf2)的蛋白表达水平。与EIF组比较,EIF+L-SAL组、EIF+M-SAL组和EIF+H-SAL组的力竭游泳时间升高,LDH、CK和cTnI水平降低,肝糖原、肌糖原、Glu和NEFA水平升高,LA和BUN水平降低,SOD和CAT水平升高,MDA水平降低,AMPKα的相对磷酸化水平以及PGC-1α、HK2、GLUT-4和MCT-1的m RNA相对表达量升高,细胞核Nrf2的蛋白相对表达量以及HO-1和NQO-1的m RNA相对表达量升高(P<0.05)。红景天苷改善运动性疲劳大鼠糖脂代谢和抗氧化系统的机制可能与AMPK途径和Nrf2途径有关,红景天苷可能是一种具有多种功效的运动营养食品添加剂。

To reveal the effects of salidroside(SAL)on glucose and lipid metabolism and oxidative stress in exercise-induced fatigue(EIF)rats.The rats were randomly divided into 5 groups with 12 rats in each group.The treating group were fed with 50,100 and 200 mg·kg^(-1)·d^(-1)salidroside,respectively.CON group and EIF group were fed with normal saline.The drug was given for 9 weeks.After 2 hours of intragastric administration,the rats in the CON group did not exercise,while the rats in the other groups received incremental load swimming exercise.The indexes of serum myocardial injury[lactate dehydrogenase(LDH),creatine kinase(CK)and cardiac troponin I(cTnI)],glycolipid metabolism indexes[liver/muscle glycogen,glucose(Glu),lactic acid(LA),urea nitrogen(BUN)and free fatty acid(NEFA)]and oxidative stress indexes of skeletal muscle[superoxide dismutase(SOD),catalase(CAT)and malondialdehyde(MDA)]were measured.The mRNA levels of peroxisome proliferator activated receptor coactivatorα(PGC-1α),hexokinase 2(HK2),glucose transporter 4(GLUT-4),monocarboxylic acid transporter 1(MCT-1),heme oxygenase 1(HO-1)and NAD(P)H:quinone oxidoreductase 1(NQO-1)in skeletal muscle were measured by RT-qPCR.The phosphorylation level of AMP-activated protein kinaseα(AMPKα)and the protein expression level of nuclear factor E2 related factor 2(Nrf2)in skeletal muscle were detected by Western blot.Compared with EIF group,the exhaustive swimming time of EIF+L-SAL group,EIF+M-SAL group and EIF+H-SAL group increased,the levels of LDH,CK and cTnI decreased,the levels of liver glycogen,muscle glycogen,Glu and NEFA increased,the levels of LA and BUN decreased,the levels of SOD and CAT increased,the level of MDA decreased,the relative phosphorylation level of AMPKαand the relative expression of mRNA of PGC-1α,HK2,GLUT-4 and MCT-1 increased,the relative expression of nuclear Nrf2 protein and the relative expression of HO-1 and NQO-1 mRNA increased(P<0.05).The mechanism of salidroside improving glucose and lipid metabolism and antioxidant system in exercise-induced fatigue rats may be related to AMPK pathway and Nrf2 pathway.Salidroside may be a kind of sports nutrition food additive with multiple effects.