Wang Y, An H, Liu T, Qin C, Sesaki H, Guo S, Radovick S, Hussain M, Maheshwari A, Wondisford FE, O’Rourke B, He L. Metformin Improves Mitochondrial Respiratory Activity through Activation of AMPK. Cell Rep. 2019 Nov 5;29(6):1511-1523.