PTGS2 and amyotrophic lateral sclerosis: We focused on the free radical nitric oxide (NO), produced by the inducible enzyme iNOS, PGE2 - a major prostanoid produced by the inducible enzyme PTGS2 during brain inflammation42 -, and the pro-inflammatory cytokines TNFα and IL6, which have been found dysregulated in vivo in ALS mouse models and patients29,43.