Protective effect of quercetin on homocysteine-induced oxidative stress

Objective: The aim of this study was to evaluate whether quercetin (QUER) treatment could have a protective effect against oxidative stress induced by homocysteinemia in rats. Materials and methods: Thirty-two male Sprague-Dawley rats (adult) were assigned randomly to four groups: the control group was given physiological saline (PS; 1.5 mL/d); the QUER group was given QUER (50 mg/kg body weight [BW] daily) in distilled water and 0.25 mL PS; the homocysteine (HCY) group was given HCY (1 mg/kg BW daily) in distilled water and 1.25 mL PS; and the QUER + HCY group was given QUER 1 h before the administration of HCY. QUER, HCY, and PS were injected intraperitoneally every other day for 30 d. Plasma malondialdehyde (MDA), carbonyl, erythrocyte-reduced glutathione (GSH), plasma sulphydril (-SH) levels, erythrocyte catalase (CAT), and superoxide dismutase (SOD) activities were determined. Results: Plasma CAT levels in the QUER group were found to be significantly higher than in the control group, whereas plasma MDA levels in the QUER group significantly decreased compared with the control group. In the HCY group, plasma MDA and carbonyl levels significantly increased and GSH and SOD levels significantly decreased compared with the control group. Plasma MDA levels significantly decreased and GSH and CAT levels significantly increased in the QUER + HCY group compared with the HCY group. Plasma -SH levels were significantly lower in the HCY group than in the control group. Plasma -SH levels were higher in the QUER + HCY group than in the HCY group, but they were not significant Conclusion: The exposure of rats to HCY leads to oxidative stress reflected in increased MDA and decreased antioxidant enzyme levels. Administration of QUER might attenuate oxidative damage induced by HCY or have a protective effect against it. (C) 2016 Elsevier Inc. All rights reserved.