PPARGC1A and type 2 diabetes mellitus: In 2003, microarray studies showed mitochondrial muscle biogenesis and oxidative phosphorylation pathways were (1) downregulated in individuals with type-2 diabetes and non-diabetics with a family history of type-2 diabetes and (2) highlighted a key role of the peroxisome proliferator coactivator 1a (PGC1α) as a master regulator of mitochondrial metabolism (78).