Betaine as a methyl donor and an antioxidant agent in levodopa-induced hyperhomocysteinemia and oxidative stress in rat's kidney

Abstract

BACKGROUND: Betaine has been shown to be antioxidant and methyl donor effects in our recent studies. OBJECTIVES: In the present study, the antioxidant and methyl donor properties of betaine in levodopa/benserazide-mediated hyperhomocysteinemia and levodopa-induced oxidative stress in rat's kidney were examined. METHODS: Sprague-Dawley male rats were divided into levodopa (LD), Betaine (Bet.), levodopa plus betaine (LD/Bet.), levodopa plus benserazide (LD/Ben.), levodopa plus betaine-benserazide (LD/Bet.-Ben.), and control groups. The experimental groups received LD (3 × 100 mg/kg), Bet. (1.5% w/w of the total diet), Ben. (3 × 25 mg/kg), and distilled water was given to controls for 10 consecutive days, orally by gavage. RESULTS: Plasma total homocysteine (tHcy) concentration decreased significantly in Bet.-, LD/Bet.-, and LD/Bet.-Ben.- treated rats compared to LD/Ben. group. Thiobarbituric acid reactive substances concentration (as a lipid peroxidation marker) in renal tissue reduced statistically in betaine group in comparison with LD and LD/Ben. groups. Renal catalase activity increased significantly in LD-treated rats when compared to controls. Renal superoxide dismutase activity significantly decreased in LD-treated group when compared to LD/Ben. group. However, there was not any significant difference in renal glutathione peroxidase (GPx) activity among the groups. CONCLUSIONS: These findings indicate that LD and LD/Ben. have side effects in kidney due to induction of hyperhomocysteinemia and oxidative stress. In contrast, betaine acts as a promising antioxidant and methyl donor agent versus LD-induced complications.