Mitochondrial metabolism regulates the epigenome. Some of the metabolites produced by OXPHOS and TCA cycle (including NAD and acetylCoA) serve as cofactors for, or used by, epigenetic factors like sirtuins (SIRTs) and histone acetyl-transferases. Δψ, mitochondrial membrane potential; CoA, coenzyme A; GSH, glutathione; GSSH, oxidized glutathione; LDH, lactate dehydrogenase; NADP, NAD phosphate; NADPH, reduced NADP; PEP, phosphoenolpyruvate; PFK, phosphofructokinase; PK, pyruvate kinase.