Redox regulation of mitochondrial biogenesis

► The physiological gases NO and CO are redox regulators of mitochondrial biogenesis. ► NO activates mitochondrial biogenesis mainly through cGMP and cAMP response element-binding protein. ► CO activates mitochondrial biogenesis mainly through reactive oxygen species and Nrf2-dependent genes. ► Adaptive mitochondrial biogenesis opposes oxidative stress and prevents energy failure.