Preliminary Insights into the Acute Molecular Responses in C2C12 Myotubes to Hyperthermia and Insulin Treatment.

Turnbull, I. C.; Gillette, R.; Nair, V. D.; Gaitas, A. D.

doi:10.1101/2025.03.26.644592

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bioRxiv · 10.1101/2025.03.26.644592

Preliminary Insights into the Acute Molecular Responses in C2C12 Myotubes to Hyperthermia and Insulin Treatment.

Turnbull, I. C.·Gillette, R.·Nair, V. D.·Gaitas, A. D.

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Abstract

This study investigates the differential gene expression in an immortalized cell line of mouse skeletal myoblasts (C2C12)-derived myotube cells subjected to hyperthermia (40{degrees}C) with and without insulin treatment to elucidate the impact of thermal stress on skeletal muscle physiology. Hyperthermia, which occurs during intense physical activity or environmental heat exposure, is known to challenge muscle homeostasis and influence metabolic function. mRNA sequencing revealed that hyperthermia robustly altered gene expression--upregulating key genes involved in glycolysis, oxidative phosphorylation, heat shock response, and apoptosis. These changes are suggestive of an elevated metabolic state and enhanced cellular stress; however, these results remain preliminary without complementary protein or metabolic assays. Notably, insulin treatment moderated many of the hyperthermia-induced transcriptional alterations, particularly affecting genes linked to glucose uptake and metabolism. Together, these findings provide hypothesis-generating insights into the interplay between thermal stress and insulin signaling in C2C12 myotubes, and they underscore potential targets for future mechanistic studies.

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Turnbull, I. C., Gillette, R., Nair, V. D., Gaitas, A. D.. 2025-03-28. Preliminary Insights into the Acute Molecular Responses in C2C12 Myotubes to Hyperthermia and Insulin Treatment.. https://doi.org/10.1101/2025.03.26.644592

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