IRS1 and osteoporosis: In osteoporosis rats, treatment with a high dose of resveratrol revealed a downregulation of Akt phosphorylation and a mechanistic target of rapamycin kinase (mTOR) phosphorylation, suggesting an involvement of the Akt/mTOR pathway in the bone cell autophagy activation induced by resveratrol [66] and the upregulation of the insulin signaling pathway through the phosphorylation of insulin receptor substrate 1 (IRS-1), PI3K, pyruvate dehydrogenase kinase 1 (PDK-1), Akt, and glycogen synthase kinase 3 (GSK-3) [67].