Cold-induced suppression of myogenesis in skeletal muscle stem cells contributes to delayed muscle regeneration during hibernation

Mammalian hibernators experience profound cold stress and prolonged physical inactivity during torpor periods; however, it is unclear how skeletal muscle stem cells (satellite cells; SCs) respond to these challenges. In this study, we demonstrate that SCs from a mammalian hibernator, Syrian hamster exhibit remarkable resistance to cold-induced cell death, which is associated with intrinsically higher expression of the antioxidant enzyme GPX4, which likely contributes to the suppression of ferroptosis. RNA-seq analysis revealed widespread downregulation of myogenesis-related genes following cold exposure, which suggests suppression of the myogenic program. Consistently, SCs exposed to cold stress exhibited reduced activation and differentiation capacities upon subsequent rewarming, with an increased number of quiescent Pax7-positive/MyoD-negative cells. Muscle regeneration was markedly delayed during hibernation, accompanied by decreased SC activation and macrophage infiltration, suggesting that cold-induced suppression of SC function underlies limited regenerative capacity in hibernating hamsters. Our results provide insight into the unique physiology of mammalian hibernators: SC viability is preserved, whereas regenerative activity is selectively suppressed during hibernation. Satellite cells (SCs) isolated from Syrian hamsters were cultured at 37°C for 48 hours after plating, followed by 24-hour incubation in GM-HEPES at 37°C, and then exposed to 4°C for 24 hours. Total RNA was extracted before and after cold exposure for RNA sequencing.