Dimethoate-induced changes in biochemical parameters of experimental rat serum and its neutralization by black seed (Nigella sativa L.) oil

Abstract

There is a considerable interest in detailed study of free radical-mediated damage to biological systems due to pesticide exposure. However, there is a lack of consensus as to which determinations are best used to quantify future risk of xenobiotic exposure and the use of natural plant products as antioxidant interventions. A purpose of this study was to investigate the effect of dimethoate on oxidative stress, biochemical parameters and enzyme activities in rat males as well as possible role of N. sativa oil (NSO) in attenuation of dimethoate-induced changes. The animals were divided randomly into 4 groups and kept at 10 rats per group. The first group was served as a control and administered with corn oil per orally; the group 2 was injected with a single dose of dimethoate (75 mg.kg-1 BW, per orally) 24 h prior to decapitation, the group 3 rats were pretreated per orally with NSO (2 ml.kg-1 BW, three times a week for three weeks), the group 4 rats were pretreated per orally with NSO (2 ml.kg-1 BW, three times a week for three weeks) prior to oral administration of a single dose of dimethoate (75 mg.kg-1 BW). Dimethoate induced (P<0.001) increase in serum thiobarbituric acid-reactive substance (TBARS) levels, superoxide dismutase (SOD) and catalase (CAT) activities and inhibited AChE activity. Treatment with NSO alone increased the activities of SOD and catalase, while decreased TBARS levels. NSO protected against dimethoate-induced lipid peroxidation and oxidative stress in these rats. Total lipid (TL), cholesterol, triglyceride (TG), and low density lipoprotein (LDL), were significantly (P<0.01) increased, while high density lipoprotein (HDL) level was decreased. NSO alone decreased levels of lipids and lipoproteins, and neutralized harmful effects of dimethoate. Dimethoate increased (P<0.01) levels of serum aminotransferases, phosphatases, lactate dehydrogenase (LDH) and gamma-glutamyl transferase (γ-GT). Urea, creatinine, uric acid and total bilirubin levels were increased, whilst serum total protein, albumin and globulin were significantly (P<0.01) decreased. The results show that NSO may neutralize dimethoate-induced changes in biochemical parameters, lipid peroxidation by activation of the antioxidant defense system in rats.