HMOX1 and myeloid sarcoma: However, others have reported increase in glutathione peroxidase in active demyelinating MS plaques [61], and increase in antioxidant enzymes (e.g., SOD1, HO-1, GPX4) in CD68+ microglia/macrophages in EAE and MS [60], which may reflect a protective response to lessen oxidative damage in certain lesions.