The purpose of this study was to investigate the influence of heat treatment on glucocorticoid (GC) -induced myopathy. Eight -week - old Wistar rats were randomly assigned to the control, Dex, and Dex + Heat groups. Dexamethasone (2 mg/kg) was injected subcutaneously 6 days per week for 2 weeks in the Dex and Dex + Heat group. In the Dex + Heat group, heat treatment was performed by immersing hindlimbs in water at 42 °C for 60 min, once every 3 days for 2 weeks. The extensor digitorum longus muscle was extracted following 2 weeks of experimentation. In the Dex + Heat group, muscle fiber diameter, capillary/muscle fiber ratio, and level of heat shock protein 72 were significantly higher and atrogene expression levels were significantly lower than in the D ex group. Our results suggest that heat treatment inhibits the development of GC -induced myopathy by decreas ing atrogene expression and increasing angiogenesis., Y. Morimoto, Y. Kondo, H. Kataoka, Y. Honda, R. Kozu, J. Sakamoto, J. Nakano, T. Origuchi, T. Yoshimura, M. Okita., and Obsahuje bibliografii
In this study, lipoic acid and heat shock treatments were applied to C2C12 myotubes and Sprague-Dawley rats to investigate changes in the heat shock protein 70 (HSP70) and glucose transporter 4 (GLUT4) in 4 different skeletal muscle groups. The results of western blotting indicated that treatment of lipoic acid for 24 h, heat-shock and combined lipoic acid and heat-shock which all increased the level of HSP70 substantially in C2C12 myotubes. However, either lipoic acid or heat-shock did not increase the level of GLUT4 in C2C12 myotubes. In an in vitro migration assay, lipoic acid increased wound migration only when it was applied for 3 h. Moreover, our in vivo results revealed that lipoic acid did not increase HSP70 and GLUT4 in all 4 different skeletal muscles. Furthermore, heat-shock increased HSP70 in all 4 different muscle groups, and heat-shock treatment alone increased the GLUT4 in the soleus muscle only, suggesting that the GLUT4 increased by heat-shock was slow-twitch muscle specific. Collectively, our results indicated that heat-shock is critical factor that modulates GLUT4 and HSP70 in the skeletal muscle of rats., P.-F. Wu, S.-C. Luo, L.-C. Chang., and Obsahuje bibliografii