Effects of Diathermy on Hsp70 Content in Human Skeletal Muscle

Abstract

Heat shock proteins are cytoprotective and have recently been shown to be involved in the repair process of myofibrils. PURPOSE: Thus, the purpose of this investigation was to determine whether short wave diathermy can increase heat shock protein 70 (Hsp70) content in skeletal muscle. METHODS: Eight subjects (6 females and 2 males, 18-35 yrs) received a muscle biopsy from the v. lateralis of one leg and then underwent 20-minutes of short wave diathermy followed by 20 minutes of hot pack heating on the other leg. Twenty-four hours following the diathermy session, another muscle biopsy was performed on the treated leg. Muscle samples were analyzed for Hsp70 content using western immunoblotting techniques. Images of the blots were obtained and analyzed using an Alpha Innotech imaging system. A paired t-Test was used to examine there were differences in Hsp70 content between the treated and untreated legs. Significance was set at P<0.05. RESULTS: Twenty four hours following the diathermy treatment Hsp70 content was on average 92% higher compared to the untreated leg (P<0.05). All but one subject (−10%) had a higher level of Hsp70 in the treated leg. CONCLUSION: This is the first study to report the effects of diathermy on heat shock protein content in humans. These results indicate that short wave diathermy is an effective modality to induce Hsp70 in skeletal muscle. Research supported, in part, by a University of Kansas General Research Fund grant (P. Gallagher), and a McNair Scholarship (T. Le).