Therapeutic Potential of Combined Therapy of Vitamin A and Vitamin C in the Experimental Autoimmune Encephalomyelitis (EAE) in Lewis Rats.

Demyelination, inflammation, oxidative injury, and glial activation are the main pathological hallmarks of multiple sclerosis (MS). Vitamins, as essential micronutrients, seem to be crucial in the pathogenesis of MS, and particularly vitamins A and C were found to have a protective role in MS development or progression. In this study, the therapeutic potential of combined therapy of vitamins A and C on progression of experimental autoimmune encephalomyelitis (EAE) and myelin repair mechanisms was examined. EAE, an animal model of MS, was induced in female Lewis rats. The rats were treated with daily intraperitoneal injections of vitamins A and C and their combination. We found that co-supplementation of vitamins A and C mitigated neurological severity and EAE disease progression. Histological study confirmed a significant reduction in demyelination size, inflammation and immune cell infiltration as well as microglia and astrocyte activation following co-administration of vitamins A and C. Co-administration of vitamins A and C also decreased the levels of pro-inflammatory cytokines (TNF-α, IL1β) and iNOS and increased gene expressions of IL-10, Nrf-2, HO-1, and MBP. Combination therapy of vitamins A and C also increased the total antioxidant capacity and decreased levels of oxidative stress markers. Finally, we proved that co-administration of vitamins A and C has anti-apoptotic and neuroprotective impacts in EAE via decreasing caspase-3 and increasing BDNF and NeuN expressing cells. The present study suggests that combined therapy of vitamins A and C may be an effective strategy for development of alternative medicine in boosting myelin repair in demyelinating diseases.