Effects of heavy load exercise and acupuncture treatment on tubulin in rat skeletal muscle / 中国组织工程研究

ABSTRACT

BACKGROUND:Heavy load exercises can induce the ultrastructural changes in the skeletal muscle by the depolymerization and/or degradation of tubulin in the skeletal muscle, thereby lessening contraction activities of the skeletal muscle. OBJECTIVE:To observe the effects of heavy load exercise and acupuncture on tubulin levels, and to analyze their roles and mechanisms in skeletal muscle injury and repair. METHODS:138 male Sprague-Dawley rats aged 8 weeks were randomly divided into acute exercise group (n=114) and long-term exercise group (n=24). The acute exercise group included four subgroupssedentary group (n=6), exercise group (n=36), acupunctured group (n=36) and exercise plus acupuncture group (n=36). In the acute exercise experiment, rats were acupunctured after a medium-large intensity downhil running. Rat’s soleus samples were taken immediately, 6, 12, 24, 48 and 72 hours after exercise and/or acupuncture. In the long-term exercise experiment, rats underwent exercise and acupuncture for 3 weeks, and rat’s soleus samples were col ected at 24 hours after the last training. Expressions ofα-tubulin and microtubule-associated protein 4 (MAP4) in the soleus were detected by western blot assay. RESULTS AND CONCLUSION:After acute exercise, expression ofα-tubulin and MAP4 was up-or down-regulated transiently. After acute exercise combined with acupuncture, the protein expressions ofα-tubulin and MAP4 changed slightly. However, the long-term exercise induced an increase inα-tubulin protein expression, while a significant decrease in MAP4 protein expression. It was worth noting that acupuncture treatment reduced long-term exercise-induced variations of MAP4 expression. These results suggest that the heavy load exercise can induce the depolymerization of tubulins in the skeletal muscle, and acupuncture may relieve this effect.