Proteomic Mechanisms of Hepatic- and Cardio-Protection of a Food-Hoarding Hibernator, Tamias sibiricus

Hibernation involves complex physiological adaptations enabling animals to survive extreme conditions. During hibernation, body temperature, metabolic rate, and heart rate change significantly but are quickly restored upon arousal. Despite extensive research, the underlying mechanisms remain unclear. This study used proteomics to examine cardiac and hepatic protein levels in food-hoarding hibernator Siberian chipmunk (Tamias sibiricus) during torpor and arousal. Results show that, unlike the fat-storing hibernators, the liver of chipmunks maintains glucose, lipid, and bile acid synthesis throughout hibernation due to changes in proteins like GALE, SLC2A3, GSK-3α, HMGCS2, ACAT2, and AMACR. In contrast, reduced mitochondrial autophagy (PINK1 and PARKIN) and enhanced anti-apoptotic mechanisms (TFRC, WFS1, and NDRG1) help maintain energy balance in the heart. These findings provide new insights into cardio-protection in food-hoarding hibernators and improve our understanding of adaptive mechanisms in mammalian hibernators.