MTOR and osteoarthritis: Furthermore, in a human in vitro model of osteoarthritis characterized by increased advanced glycation end (AGE) products accumulation and reduced autophagy, it was demonstrated that pioglitazone, a PPARγ ligand, increased AKT/mTOR phosphorylation in a dose-dependent manner, leading to better cell viability and inducing increased chondrocyte autophagy (43).