Tomato pomace protects against mercuric chloride-induced neurodegeneration and motor abnormality in adult rat

Abstract

Mercuric chloride is an environmental toxicant that causes health hazards. One of the mechanisms of its toxicity is oxidative stress which antioxidants are expected to ameliorate. Tomato is reported to possess antioxidant activity and this study investigated tomato pomace powder’s (TPP) effect on mercuric chloride (HgCl₂) intoxication in rats. Thirty male rats were assigned randomly into five groups (n=6): Control; Propylene glycol; TPP (50 mg/kg bwt) for 19 days; HgCl₂ (4 mg/bwt) from day 5 to 19 of the experiment; TPP +HgCl₂, TPP (50 mg/kg bwt) for 19 days + HgCl₂ (4 mg/bwt) from day 5 to 19 of the experiment. All treatments were given orally by gavage. Behavioural tests were conducted on the 20th day and rats were euthanized the same day. Blood parameters and brain tissue were examined with regard to micro-anatomical parameters. Mercuric chloride significantly reduced neutrophils, thrombocytes, transitions, rearings, forelimb grip strength and latency of geotaxis. Histologically, HgCl₂ induced alterations in the cerebral cortex, dentate gyrus, cornu ammonis3, and cerebellum of rats. Treatment with TPP before HgCl₂ administration significantly reduced the effect of HgCl₂ on these parameters. These observations may be partly attributed to the antioxidant property of TPP. TPP demonstrated protective effects against HgCl₂-induced alteration of motor anomaly and microanatomy of rats’ cerebral cortex, hippocampus and cerebellum. TPP may be a valuable agent in prevention of acute neuropathy caused by inorganic mercury intoxication.

Keywords: Mercuric chloride, cortical neurons, granule cells, cornu ammonis3 pyramidal neurons, Purkinje neurons, tomato.