Coming back to the concept of the iron-mediated toxicity in ALS, it is tempting to propose that in SOD1G93A mice HO1 acts together with ferritin to limit the reactivity of heme-derived intracellular iron as it was originally demonstrated in endothelium under hemolytic conditions (Balla et al., 1992). Here, HMOX1 is linked to amyotrophic lateral sclerosis.