Uric Acid Administration Attenuates Severe Protracted Relapsing Remitting Experimental Autoimmune Encephalomyelitis in Dark Agouti rats.

Uric Acid (UA) is the final product of the purine nucleoside metabolism, acts physiologically as plasma antioxidant and is a known peroxynitrite scavenger. Several studies have reported lower serum concentrations of UA in Multiple sclerosis (MS) patients. In this study, we examined the effect of UA administration on severe protracted relapsing remitting experimental autoimmune encephalomyelitis (SPR-EAE) in Dark Agouti (DA) rats, an animal model of MS. Compared to placebo, daily UA treatment for either 12 or 23 days after immunization significantly reduced the clinical course and severity of disease. It also suppressed all aspects of inflammation, nitric oxide and peroxynitrite formation, axonal damage and demyelination. These findings suggest that UA might be beneficial in MS treatment by preventing tissue and molecular alterations due to its capacity to neutralise the toxic effect of peroxynitrite. [ABSTRACT FROM AUTHOR]