Erythrocyte glutathione peroxidase, catalase, and superoxide dismutase activities were measured in 18 patients with clinically definite MS, and results compared with those from neurological controls. These studies indicated that glutathione peroxidase activity in erythrocytes of MS patients was not different from that of the neurological controls. However, superoxide dismutase was lower in the MS patients compared to neurological controls. The effect of hyperbaric oxygenation on these erythrocyte enzymes in MS patient’s was also investigated. Exposure of MS patients to 2 ata with either 10% O2 or 100% O2 had no effect on glutathione peroxidase activity. Comparison of each individual MS patient’s pre- and post-treatment superoxide dismutase values indicated a significant increase after 100% O2. Similar examination of each individual’s catalase activity indicated an increase after exposure to both 10% O2 and 100% O2 at 2 ata. These data suggest that erythrocyte enzyme response to oxygen stress does not involve changes in activity of all the antioxidant enzymes. Instead, only specific enzymes appear to be affected by HBO.

Ansari, Wilson, Slater, Haglin, Kaplan, , , , (1986). Hyperbaric oxygenation and erythrocyte antioxidant enzymes in multiple sclerosis patients. Acta neurologica Scandinavica, 1986 Aug;74(2):156-60. https://www.ncbi.nlm.nih.gov/pubmed/3776462