Moderate superoxide production is an early promoter of mitochondrial biogenesis in differentiating N2a neuroblastoma cells

► Differentiation of N2a cells is associated with an increase in mitochondrial mass. ► An early, moderate increase in superoxide is observed in differentiating cells. ► O2− scavenging prevents mitochondrial biogenesis and differentiation. ► MAPK inhibition prevents mitochondrial biogenesis and differentiation. ► Mitochondriogenesis and differentiation are part of a O2− mediated hormetic response.