PGC-1 alpha overexpression in the skeletal muscle results in a metabolically active microbiome which is independent of redox signaling

In this study, we investigated the potential relationship between the mitochondrial network and the microbiome using wild-type and skeletal muscle-specific PGC-1α (Pparg coactivator 1 alpha) overexpressing mice, both with and without exercise training. PGC-1α levels were significantly elevated in skeletal muscle and, notably, in the colon, which is anatomically proximal to the microbiome. However, no significant changes were observed in cell signaling or mitochondria-related proteins within the colon. On the other hand, mitochondrial H₂O₂ production in the colon decreased in the PGC-1α overexpressing group. The relative abundance of several bacterial taxa differed between wild-type and PGC-1α overexpressing groups, indicating a shift in the microbiome milieu probably to cope with the increased metabolism, enhanced short-chain fatty acid utilization, and improved endurance capacity. Ten weeks of exercise training differentially modulated the host microbiome in PGC-1α overexpressing and wild-type mice, facilitating adaptations to a broad range of exercise-induced challenges. The results of this study provide new insights into the possible cross-talk between mitochondria and the microbiome.