Anti-apoptotic and anti-oxidant effects of systemic uridine treatment in an experimental model of sciatic nerve injury

To investigate the anti-apoptotic and anti-oxidant effects of systemic uridine administration in a rat model of sciatic nerve injury. Thirty-two adult male rats were randomized equally to Sham, Control, U100 and U500 groups. Sham rats received a sham operation by exposing right sciatic nerve without transection, while those in the Control, U100 and U500 groups underwent right sciatic nerve transection followed by immediate primary anostomosis. Sham and Control groups received saline (0,9% NaCl) injections intraperitoneally (i.p.), while U100 and U500 groups received 100 mg/kg and 500 mg/kg uridine injections (i.p.), respectively, once a day for 7 days after the surgery. Rats in all groups were sacrificed on the eighth day and sciatic nerve samples were analyzed for apoptosis by Western Blotting and for oxidation parameters including myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) by Enzyme-Linked Immunosorbent Assay (ELISA). Uridine treatment at the dose of 500 mg/kg significantly decreased apoptosis determined by Caspase-3/Actin ratio and exhibited significant anti-oxidant effects determined by decreased levels of MPO and MDA as well as increased levels of SOD, GPx and CAT compared to controls. Uridine at 100 mg/kg only tended to decrease Caspase-3/Actin ratio but significantly decreased MDA and increased CAT levels compared to controls. Treatment with uridine dose-dependently reduces apoptosis and oxidation in a rat model of sciatic nerve injury. Thus, uridine may provide benefit in peripheral nerve regeneration by exhibiting anti-apoptotic and anti-oxidant effects.