中链甘油三酯对模拟高热高湿环境下小鼠抗疲劳的作用

Anti-fatigue effect of medium-chain triglyceride on mice in the high-temperature and high-humidity environment

目的研究中链甘油三酯(MCT)在高热高湿条件下抗疲劳的效果和机制。方法将60只雄性ICR小鼠随机分为5组:常温对照组(CC组)、高温对照组(GC组)、运动对照组(SC组)、MCT对照组(MC组)和MCT训练组(MS组)。GC、SC、MC、MS各组每日在温度(36±2)℃,湿度(60±3)%的环境下进行热习服30 min,习服后在相同环境下进行转棒训练30 min。21 d后,各组取6只小鼠在温度(38±2)℃,湿度(60±3)%)环境下,测定转棒力竭时间。SC组、MS组取其余6只小鼠转棒运动30 min后,取血、肝脏、骨骼肌,CC组、SC组、MC组直接取材,并测定血糖、甘油三酯、血清乳酸脱氢酶、肌酸激酶、肝脏糖原、游离脂肪酸含量,以及股四头肌PGC-1α的表达。结果 MCT和运动可以显著延长小鼠在高温高湿环境下转棒力竭时间(P<0.01),与SC组相比,显著降低乳酸脱氢酶、肌酸激酶、血糖和游离脂肪酸(P<0.05),增加肝糖原含量(P<0.05),上调PCG-1α(P<0.05)。结论 MCT可显著提高小鼠在高温高湿环境下抗疲劳能力,其机制与MCT增加骨骼肌代谢调节因子表达,调节糖脂代谢,从而提高运动耐力有关。

Objective To investigate the anti-fatigue effect of medium-chain triglyceride（MCT） on mice in the high-temperature and high-humidity environment,and explore the related mechanism. Methods 60 male ICR mice were randomly divided into 5 groups： normal temperature control group（CC group）,high temperature control group（GC group）,exercise control group（SC group）,MCT control group（MC group）,MCT train group（MS group）. For GC,SC,MC and MS groups,mice were acclimated for 30 min at the temperature of（36±2）℃ and humidity（60±3）% for 30 min,and then underwent for rotarod training for 30 min everyday. Twenty-one days later,6 mice in each group were underwent rotarod test to determine the rotarod-exhausted time at the temperature of（38±2）℃,and humidity（60±3）%. The other 6 mice of the SC group and MS group underwent 30 min rotarod test at the same condition and then sacrified to colllect blood,liver and muscle samples.Samples also collected from the CC group,SC group and MC group. Blood glucose,triglyceride,lactate dehydrogenase,creatine kinase,hepatic glycogen,free fatty acid content,and PGC-1α expression in quadriceps femoris muscle were determined. Results Both medium-chain triglyceride and exercise could significantly prolong the rotarod-exhausted time in the high-temperature and high-humidity environment（P〈0.01）. The levels of the serum lactate dehydrogenase,creatine kinase and blood glucose were significantly reduced（P〈0.05）,while PCG-1α was increased（P〈0.05）. Conclusion Medium-chain triglyceride could obviously improve the anti-fatigue capacity of the mice in high temperature and high humidity environment,and its mechanism of improving exercise endurance might be related to the increase in the expression of skeletal muscle metabolism regulator and regulate the glucose and lipid metabolism.