Comprehensive multi-organ reference map of mitochondrial function in swine

Traumatic brain injury (TBI) often occurs alongside polytrauma, which involves injuries to vital organs, resulting in severe compounded effects to the body. Our research program has been involved in broadening the understanding of organ-specific cellular responses relevant to TBI exposures in the military. In the current study, we collected reference data from multiple organs and brain regions on mitochondrial functional parameters using adult naive control swine. With their large brain mass and gyrencephalic architecture, the swine model has been utilized to develop and replicate experimental TBI and polytrauma conditions. In the present study, mitochondria were freshly isolated from Yorkshire male swine (30-35 kg) vital organs (e.g., brain, heart, lung, liver, kidney, spleen, muscle and intestine) and brain regions (e.g., cortex, striatum, cerebellum and hippocampus). Real-time analyses of mitochondrial bioenergetics and calcium (Ca²⁺) buffering experiments were conducted within multi-organs, and brain regions samples. Remaining mitochondrial samples were immediately stored and later used to evaluate cell death responses by assessing mitochondrial membrane integrity and antioxidant marker protein expression. Overall, our findings revealed organ-specific, and brain region-specific patterns of mitochondrial functional outcomes in healthy control swine. Notably, brain and heart mitochondrial bioenergetics and Ca²⁺ buffering capacity exhibited higher compared to other organs. Organ-specific unique differences were also identified in mitochondrial membrane integrity and cell death markers (i.e., Complex IV, Cyt C, VDAC, and Bcl-2), and antioxidant protein markers (i.e., SOD, CAT, TRX, and PRX). These baseline reference data establish a foundation for future injury-model studies of mitochondrial responses in TBI and polytrauma.