Modification of Hexavalent Chromate Hepatotoxicity by Ethanol Extract of Moringa oleifera in Wistar Rats

Background: The association of hexavalent chromate toxicity with oxidative stress necessitated the search for antidote from medicinal plants with antioxidant properties. One of such plants is Moringa oleifera. Objective: To investigate the hepatoprotective and antioxidative properties of ethanol extract of Moringa oleifera (EEMO) against potassium dichromate (K₂Cr₂O₇) induced hepatocellular damage and oxidative stress in male Wistar rats. Materials and Methods: Thirty rats were assigned into six groups of five animals each: distilled water, 12 mg/kg bd.wt K₂Cr₂O₇, 3.5 mg/kg bd.wt EEMO, 7.0 mg/Kg bd.wt EEMO, 3.5 mg/Kg bd.wt EEMO+K₂Cr₂O₇, 7.0 mg/kg bd.wt EEMO+K₂Cr₂O₇. The EEMO was administered consecutively for thirty-five days, while K₂Cr₂O₇ was injected intraperitoneally once weekly before the animals were sacrificed. Liver function and oxidative stress markers including alanine aminotransferase (ALT), aspartate aminotransferase (AST), superoxide dismutase (SOD), glutathione -S-transferase (GST) and malondialdehyde (MDA) levels were monitored in the serum and liver. Histopathology of the liver was also carried out. In addition, proximate analysis of the powdered leaves and phytochemical composition of EEMO were also evaluated. Results: The K₂Cr₂O₇ significantly (p < 0.05) increased AST, ALT and MDA levels coupled with decreased SOD and GST activities as well as hepatic lesions when compared with control. However, the two doses of EEMO modified the hepatotoxicity and oxidative stress towards that of control. The EEMO is rich in phenolics and other phytochemicals including hexamethylquercetagetin and hexa-Omethylmyricitin that may account for the observed antioxidative and ameliorative effect. Conclusion: Our results suggest that ethanol extract of Moringa oleifera modify hexavalent chromate hepatotoxicity by reducing oxidative stress.