摘要
目的:旨在研究肌酸补充(CS)和电刺激(ES)对C2C12肌管葡萄糖摄取相关通路蛋白含量和基因表达的影响,阐明肌酸对GLUT4调节的相关信号通路,并讨论CS是否对ES具有叠加效应,为肌酸提高耐力水平提供新的理论依据。研究方法:0.5mM和2 mM浓度的肌酸孵育分化5 d的肌管48h,然后电刺激(15V,30ms,3Hz)共分化7d的肌管120 min。结果:ES引起AMPK-α2和GLUT4 mRNA表达及GLUT4蛋白含量显著增加(P<0.05),糖原显著下降(P<0.05)。不同浓度的CS没有引起AMPK-α2 mRNA表达变化,却使得GLUT4 mRNA和蛋白含量显著增加(P<0.05),糖原含量也无显著性增加(P>0.05)。ES+CS组与C组和同浓度CS组相比,明显上调AMPK-α2 mRNA和GLUT4 mRNA表达及GLUT4蛋白含量(P<0.05)。结论:1)15V,30ms,3Hz的刺激参数,ES120min没有引起细胞膜明显损伤,是研究耐力运动对肌肉糖代谢影响的适合参数。2)ES能通过AMPK途径增加肌管糖摄入和糖转运。3)单纯CS对肌管糖含量没影响,肌酸或许是通过AMPK非依赖性通路调节糖摄入。4)CS对ES对糖摄入的调节具有叠加效应。
Objective： The study was designed to investigate the effect of creatine supplementation （CS） and elec-trical stimulation （ES） on the protein content and gene expression in the pathway related with glycogen and glu-cose intake in differentiated C2C12 myotubes, so as to further discuss whether CS has the superimposed effect on ES which may provide a new evidence of CS on athletic performance enhancement. Methods ： Myotubes were incu-bated in 0.5 mM or 2 mM dose of creatine for 48 hours when differentiated for 5 days, then myotubes which were differentiated totally for 7 days were stimulated to contract 120 min at 15 V, 30 ms, 3 Hz. Results： Significant up-regulation of AMPK-α2 and GLUT4 mRNA expression and GLUT4 protein content can be seen in ES group （ P 〈 0.05 ）, glycogen content decreased significantly in ES group （ P 〈 0.05 ）. Different concentration of CS did not alter AMPK-α2 mRNA expression, however it increased GLUT4 mRNA and GLUT4 protein expression （ P 〈 0.05 ）, but no significant increase of glycogen content （ P 〉 0.05 ）. ES ＋ CS up-regulated AMPK-α2 mRNA ex- pression, GLUT4 mRNA and GLUT4 protein expression （P 〈 0. 05） compared with control group and same dosage of pure CS group. Conclusion： 1 ） C2C12 mytubes electrical stimulated at 15 V, 30 ms, 3 Hz for 120 min is fit for study the glucose metabolism of muscles caused by endurance exercise without causing the damage of cell mem-brane. 2） ES accelerated glucose intake and transportation through AMPK-α2 activation. 3） CS had no effect on glycogen content in motionless muscles. Creatine may through an AMPK-independent way in regulation of glucose intake. 4） CS has the superimposed effect on ES.
出处
《北京体育大学学报》
CSSCI
北大核心
2013年第2期48-54,共7页
Journal of Beijing Sport University
基金
广东省体育局科研基金课题(20120NS046)
关键词
C2C12
电刺激
肌酸补充
糖摄入
叠加效应
C2C12
electrical stimulation
creatine supplementation
glucose uptake
superimposed effect
