MFN1 and metabolic syndrome: We previously evidenced in ‘in vitro’ studies with PBMCs of metabolic syndrome patients that a low rate of H2O2 production can enhance the expression of mitochondrial dynamics-related proteins such as Mfn2, whereas a high rate of H2O2 production diminishes the expression of mitochondrial dynamics-related proteins such as Mfn1 and Tfam [61].