ANTIOXIDANT AND CHEMOPREVENTIVE EFFECT OF AZADIRACHTA INDICA ON LEAD ACETATE INDUCED HEPATOTOXICITY IN RATS

Abstract

Lead (Pb), a ubiquitous heavy metal is known to be injurious to all systems. Oxidative damage has been shown to be one of the principal mechanisms by which Pb causes toxicity. In this study, hepatic antioxidant status and markers of oxidative stress were assessed in experimental animals orally exposed to lead acetate (PbA) and was compared with groups treated with the methanolic extract of Azadirachta indica at 2 different doses.Seventy rats were used in this study. They were divided into 7 groups each containing 10 animals. Control group (group A) received water only. Group B, C and D were dosed 0.1% lead and was withdrawn after 6 weeks. On withdrawal, Group B received water only while groups C and D were treated with 100mg/kg and 200mg/kg of the methanolic extract of Azadirachta indica respectively for 6 weeks. Similarly, groups E, F, G were given 0.2% lead orally and was withdrawn after 6 weeks. On withdrawal, group E received water only while groups F and G were treated with 100mg/kg and 200mg/kg A. indica respectively for 6 weeks.Exposure of rats to lead acetate led to a significant (p<0.05) reduction in hepatic reduced Glutathione (GSH), Glutathione peroxidase (GPX) and Glutathione S‐ transferase. Similarly, Malondialdehyde (MDA) content increased (p<0.05) significantly in animals dosed PbA alone while there was a significant (p<0.05) reduction in rats treated with A. indica. There was significant (p<0.05) increase in nitric oxide (NO) and H2O2 concentrations in rats treated with PbA alone whereas treatment with A. indica led to significant (p<0.05) reduction in these markers of oxidative stress. Histology showed the presence of high periportal infiltration with inflammatory cells and focal necrosis in PbA treated groups but periportal infiltration was mild in Rats dosed with A. indica. In conclusion, animals exposed to PbA showed hepatotoxicity and disruption of antioxidant defence system through free radical generation and oxidative stress. Treatment of PbA exposed rats with A. indica led to significant amelioration of the hepatotoxicity induced by PbA. In conclusion, this study demonstrated the hepatoprotective effect of A. indica via antioxidant and free radical scavenging activities.Support or Funding InformationNone