Chronic oxidative and nitrosative stress causes damage to proteins, lipids, and DNA, and plays an important role in the pathogenesis and tissue damage of MS and EAE.[52, 159] PARP1 is activated in neurons upon exposure to free radicals nitric oxide (NO),[160] peroxynitrite,[161] hydrogen peroxide (H2O2),[83c] DNA alkylating agents MNNG,[83, 85] and excitotoxic agent N‐Methyl‐D‐aspartate (NMDA).[83, 158] PARP1 activation was shown to mediate necrotic neuron death by these agents through NAD+ depletion and energy failure. Here, PARP1 is linked to myeloid sarcoma.