The effect of acute and chronic thermotherapy on type 2 diabetic skeletal muscle gene expression and inflammatory markers

Background: Type 2 diabetes (T2D) is a chronic illness associated with resistance or defective insulin secretion. This study investigated the effects of thermotherapy on cell viability, gene expression, and inflammation in skeletal muscle cell lines. Methods: Healthy and T2D hu-man skeletal muscle cell lines (HSMM and D-HSMM, respectively) were subjected to acute or chronic thermo-therapy (AT or CT, respectively). The CT consisted of a 30-minute exposure to 40°C, three times a week for three weeks; the AT was a one-time exposure. Results: Significant de-crease in D-HSMM cell viability percentage followed the AT; however, no significant change occurred in CT. HSMM yielded the highest elevations of genes following the CT. In D-HSMM, both treatments yielded genes up-regulation. Both treatments significantly down-regulated IL-1β, IL-6, IL-10, and TNF-α in HSMM. AT significantly decreased IL-1β, IL-6, and upregulated IL-10 and TNF-α levels in D-HSMM, while CT yielded a reduction in IL-4, TNF-α, and an up-regulation of IL-6 and IL-10. Conclusion: Increase in gene expression indicates actin activity, and cellular responses, suggesting an increase in transcriptional regulation. The upregulation of IL-6 and IL-10 in D-HSMM negatively correlated with a decrease in TNF-α and IL-1β, indicating improved adverse inflammatory effects associated with the disease.