Morinda lucida stem bark reversed the pattern and extent of lead nitrate-induced liver injury in Wistar rats.

Lead toxicity remains one of the most important occupational and environmental health problems with characteristic features that are incompatible with life. Considering the foregoing, we investigated the ameliorative potentials of Morinda lucida stem bark (MLSB) extract on lead nitrate-induced hepatic injury with particular emphasis on its effects on the pattern and extent of lead nitrate toxicity. Thirty-six adult Wistar rats were randomly assigned into six groups (n=6). Normal control group received 2.2mL/kg distilled water only for 4 weeks while hepatic injury was induced by 2-week oral administration of 30mg/kg lead nitrate to experimental rats in the remaining five groups. Following induction, test groups were treated with MLSB for another 2 weeks at 100, 250, and 500mg/kg concentrations respectively while silymarin was administered orally for 2 weeks to positive control group. At the end of the study, serum activities of liver function enzymes and tissue levels of malondialdehyde were determined. Patterns and extent of injury were determined in hematoxylin and eosin-stained section. The result revealed a significant reduction in sera levels of liver function enzymes and tissue level of malondialdehyde (MDA) in extract treated groups. Lead nitrate-induced necrotic changes and other deranged features observed in histological sections were multifocal and they span through multiple zones of hepatic acini (panacinar), MLSB at 250mg/kg concentration reversed by some of these effects. The study concluded that ameliorative property of MLSB could be due to the antioxidant and membrane stabilizing properties of its phenolic compounds.