PPARGC1A and Parkinson disease: PGC-1α, which regulates mitochondrial biogenesis and expression of many antioxidant genes, plays an important role in protection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity [15], and expression of genes regulated by PGC-1α are reduced in substantia nigra neurons at early stages of PD [20].