PPARGC1A and Insulin resistance: PPARGC1A upregulates transcription of genes involved in mitochondrial oxidative metabolism and biogenesis as well as skeletal muscle glucose transport [11], [12], and because mitochondrial defects have been associated with peripheral insulin resistance in healthy subjects [13], [14] it has been suggested that reduced PPARGC1A expression in skeletal muscle may be a primary feature of insulin resistance [11], [15].