摘要
目的:探讨高F值玉米肽提高运动能力的效果及分子机制,为将其开发为抗运动疲劳营养补剂提供理论支持。方法:将80只SD大鼠随机分为4组,即空白对照组和高F值玉米肽低、中、高剂量组。每日上午低、中、高剂量组分别给予高F值玉米肽0.1、0.2、0.4 g/kg m_(b),空白对照组给予同等剂量生理盐水,下午进行无负重游泳训练,训练时间1 h/d、每周第1~5天连续运动5 d、安静状态休息2 d,持续8周,最后一次实验结束后次日进行负重力竭运动并记录时间,测定血乳酸水平。待安静状态休息3 d后处死大鼠,取外周血和骨骼肌组织,检测骨骼肌中丙二醛(malondialdehyde,MDA)水平及超氧化物歧化酶(superoxide dismutase,SOD)、三磷酸腺苷(adenosine triphosphate,ATP)合成酶和水解酶活力,采用Western blot法检测抗氧化应激蛋白核因子2相关因子2(nuclear factor erythroid-2 related factor 2,Nrf2)与Kelch样ECH关联蛋白1(Kelch-like ECH-associated protein 1,Keap1)以及线粒体融合蛋白(mitofusin2,Mfn2)与线粒体分裂蛋白动力相关蛋白(dynamin-related protein,Drp1)的表达量。结果:与对照组相比,高F值玉米肽干预显著延长小鼠力竭运动时间(P<0.05),且呈剂量依赖性;同样,高F值玉米肽显著降低力竭运动后5 min以及15 min血乳酸水平(P<0.05),且高剂量组血乳酸水平显著低于低剂量组(P<0.05);高F值玉米肽干预组大鼠骨骼肌中ATP合成酶和水解酶活力与对照组相比总体显著提高(P<0.05),且呈剂量依赖性;口服高F值玉米肽能够提高实验大鼠骨骼肌中SOD活力,降低MDA水平;此外,高F值玉米肽能够提高大鼠细胞核内Nrf2和胞质中Keap1蛋白表达水平,同时明显提高Mfn2的表达水平,降低线粒体裂解蛋白Drp1的表达水平。结论:高F值玉米肽可以通过改善骨骼肌线粒体功能提高实验大鼠的运动能力。
Objective:To explore the effect and molecular mechanism of high F-value corn peptide on improving exercise capacity,so as to provide theoretical support for its development as a sports nutritional supplement.Methods:Eighty SD rats were randomly divided into four groups:a control group and high F-value corn peptide with low-dose,medium-dose and high-dose groups.Each morning,the rats in low-dose,medium-dose and high-dose groups were orally administered with 0.1,0.2 and 0.4 g/kg m_(b) of high F-value corn peptide respectively,and the rats in the control group were administered with the same volume of normal saline.All rats received one-hour swimming training without weight loading every day over a period of 8 weeks and also performed exercise in the first five days every week with two-day intervals.After the last treatment,weight bearing exercise was carried out and the time to exhaustion was recorded.Blood lactate levels were determined as well.After being at rest for three days,the rats were sacrificed to harvest peripheral blood and skeletal muscle tissue.Subsequently,commercial test kits were used to measure malondialdehyde(MDA)concentration,and the activities of superoxide dismutase(SOD)activity and adenosine triphosphate(ATP)synthase and hydrolase in muscle.Meanwhile,the expression of the antioxidative stress regulator nuclear factor erythroid-2 related factor 2(Nrf2),Kelch-like ECH-associated protein 1(Keap1),the mitochondrial fusion protein mitofusin 2(Mfn2)and the mitochondrial fission protein dynamin-related protein 1(Drp1)were detected by Western blot analysis.Results:Compared with the control group,high F-value corn peptide significantly prolonged the exhaustive exercise time of mice(P<0.05)in a dose-dependent manner,and dramatically reduced the level of blood lactic acid at 5 and 15 min after exhaustive exercise(P<0.05).The level of blood lactic acid in the high-dose group was significantly lower than that in the low-dose group(P<0.05).In addition,high F-value corn peptide dose-dependently significantly elevated the activities of ATP synthase and hydrolase in skeletal muscle of rats compared to the control group(P<0.05).We also found that oral administration of high F-value corn peptide could increase SOD activity and reduce MDA production in skeletal muscle of experimental rats,increase the expression of Nrf2 in the nucleus and of Keap1 protein in the cytoplasm,significantly increase the expression of Mfn2,and significantly reduce the expression of Drp1.Conclusion:High F-value corn peptide improves exercise capacity in experimental rats by improving the mitochondrial function of skeletal muscle.
作者
刘金美
付翠元
马坤
李哲
贾绍辉
LIU Jinmei;FU Cuiyuan;MA Kun;LI Zhe;JIA Shaohui(College of Health Science,Wuhan Sports University,Wuhan 430079,China;Institute of Physical Education,Jinan University,Jinan 250024,China;College of Economics and Business,Hubei Open University,Wuhan 430074,China;Hubei Key Laboratory of Exercise Training and Monitoring,Hubei Province Collaborative Innovation Center for Exercise and Health Promotion,Wuhan Sports University,Wuhan 430079,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2022年第21期218-225,共8页
Food Science
基金
湖北省自然科学基金项目(2018CFB729)
武汉体育学院中青年科研创新团队项目(21KT14)。
