Cardiometabolic adaptations in the cave nectar bat Eonycteris spelaea

Bats are the only mammals capable of powered flight, a physiologically demanding process requiring substantial cardiac energy expenditure. Here, we investigate how hearts of the cave nectar bat Eonycteris spelaea are adapted to meet these extreme demands. Transcriptomic profiling reveals enriched signatures of oxidative phosphorylation and fatty acid metabolism in bat hearts, distinct from mouse and human counterparts. Metabolomics analyses corroborate these findings, identifying distinct acylcarnitine profiles and elevated tricarboxylic acid cycle intermediates. Anatomically, bats have relatively larger hearts with increased mitochondrial and vascular densities along with prominent perivascular adipocytes. Echocardiography reveals superior cardiac reserve in bats, with enhanced contractile responses under dobutamine stress. Notably, isolated bat cardiomyocytes resist angiotensin II-induced hypertrophy and mitochondrial dysfunction. These integrated adaptations likely support high-energy flight while preserving cardiac function under stress. Insights from bat cardiac physiology may provide valuable information on cardioprotective mechanisms with potential application across species.