Pumpkin seed oil alleviates oxidative stress and liver damage induced by sodium nitrate in adult rats: biochemical and histological approach

Abstract

Background: Nitrate (NO3) is the most common chemical contaminant in the world’s ground water aquifer. Oxidative stress has been proposed as a possible mechanism involved in NO3 toxicity on non-target organism. Objectives: The current study aimed to elucidate the potential protective effect of Telfairia occidentalis (pumpkin seed oil, PSO) against hepatotoxicity induced by sodium nitrate. Methods: Wistar rats were exposed either to NaNO3 (200 mg/kg bw) in drinking water in drinking water, or to 4ml PSO/kg bw by gavage or to their combination. Oxidative stress parameters, biochemical biomarkers and liver histopathological examination were determined. Results: Our data showed that the exposure of rats to NaNO3 caused significant changes of some haematological parameters compared to the control. In addition, there was a significant elevation of the levels of biochemical markers as that of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase when compared with the control. Furthermore, exposure of rats to NaNO3 induced liver oxidative stress as indicated by the increase of malondialdehyde, pro- gressive oxidation of protein products and protein carbonyl levels. In addition, a reduction in anti-oxidant status (catalase, glutathione peroxidase, glutathione-S-transferase and superoxide dismutase, reduced glutathione and vitamin C) was observed. Conclusion: Co-administration of PSO to the NaNO3 restored most parameters cited above to near-normal values. Therefore, the present investigation revealed the ability of PSO to attenuate NaNO3-induced oxidative damage. Keywords: Sodium nitrate; Telfairia occidentalis; pumpkin seed oil; hepatotoxicity; oxidative stress; protection; anti-oxidant status, rat.