Histopathological Evidence of the Protective Effect of Arachis hypogea Seed on 1,2-Dimethylhydrazine-Dihydrochloride-Induced Liver Damage in Rats

This study examined the effect of peanut-supplemented diet on the serum antioxidant status and histomorphological changes induced by 1,2-dimethylhydrazine-dihydrochloride on rat liver. Twenty-eight healthy albino Wistar rats used for this study were divided into seven groups of 4 rats each. The toxicant, 1,2-dimethylhydrazinedihydrochloride (DMH), was administered subcutaneously at a dose of 25 mg/kg body weight. Group A (control) rats were maintained on normal rat feed. The Group B and C rats were maintained on normal feed, administered DMH for 12 and 24 weeks respectively. Incorporation of peanut into the diet was varied depending on the group, 12 weeks after DMH administration (Group D), concomitantly with DMH administration for 24 weeks (Group E) and 12 weeks before the administration of DMH (Group F). Group G rats were maintained on a peanut-supplemented diet only for 24 weeks. At the end of the treatment period all the animals were sacrificed under mild anaesthesia and blood collected by heart puncture. Portions of the liver were excised and fixed for histopathological examination. The result showed that DMH significantly (p ≤ 0.05) increased serum MDA levels, this elevated MDA levels was reversed by the supplementation of the rat feed with peanut powder. There were also significant (p ≤ 0.05) decreases in antioxidant enzymes, superoxide dismutase, catalase and glutathione peroxidase activities in the groups that received DMH alone which were reversed in the groups exposed to DMH and peanut-supplemented diet. Histopathology results showed that DMH administration resulted in varying degrees of necrosis and fibrosis while the prophylactic administration of peanut incorporated diet to the rat resulted in normal liver architecture. Incorporation of peanut powder therefore has the ability to protect the liver from 1, 2-dimethylhydrazineinduced liver damage and also reduces oxidative stress markers while improving antioxidant enzyme activities.