MPO and amyotrophic lateral sclerosis: The MPO/hypochlorous acid neuroinflammatory pathway was activated in motor neurons in an in vivo ALS mouse study, where motor performance improved after MPO inhibition.12 Postmortem MPO levels were higher in human amyotrophic lateral sclerosis (ALS) brain tissue than in controls without ALS.13 Altogether, these studies are supportive of the possibility that MPO activation may be deleterious in ALS and that its inhibition may be beneficial.