title: Heat-shock-induced glucose transporter 4 in the slow-twitch muscle of rats.
abstract: In this study, lipoic acid and heat shock treatments were applied to C(2)C(12) 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 C(2)C(12) myotubes. However, either lipoic acid or heat-shock did not increase the level of GLUT4 in C(2)C(12) 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.
authors.affiliation: Department of Kinesiology, Health and Leisure Studies, National University of Kaohsiung, Kaohsiung, Taiwan. anniepf@nuk.edu.tw.
authors.forename: P-F
authors.initials: PF
authors.lastname: Wu
authors.forename: S-C
authors.initials: SC
authors.lastname: Luo
authors.forename: L-C
authors.initials: LC
authors.lastname: Chang
mesh_terms: D000818:Animals; D002460:Cell Line; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D018869:Heat-Shock Response / Q000502:physiology*; D008297:Male; D018657:Muscle Fibers, Slow-Twitch / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D051275:Glucose Transporter Type 4; D018840:HSP70 Heat-Shock Proteins; C495694:Slc2a4 protein, rat