Indeed, β-guanidinopropionic acid treatment increased the number of mitochondria and stimulated the expression of AMPK, PGC-1α, PGC-1β, Tfam, COX-IV, PPARα, PPARδ, Cytochrome C and cAMP response element binding protein (CREB) that are involved in oxidative phosphorylation, electron transport chain and muscle function in wild-type mice, whereas had no effect on HD mice [76]. The gene discussed is PPARGC1A; the disease is Huntington disease.