Lead nitrate toxicity: its effects on hepatic extracellular matrix fibers, filamentous cytoskeleton and the mitigative potentials of Morinda lucida extract

•Lead nitrate accumulation cause severe deleterious effect on the cellular and cytoskeletal structure of the liver.•Efficacy of Morinda lucida, a medicinal plant, in the mitigation of lead nitrate-induced cellular, cytoskeletal and extracellular alterations in the liver was investigated in Wistar rats.•Morinda lucida significantly reversed lead-nitrate-induced hepatocellular, cytoskeletal and extracellular changes in Wistar rats.•Possible ameliorative property of Morinda lucida could be due to the antioxidant and membrane stabilizing properties of its phenolic compounds. In this study, the effect of orally administered methanolic extract of Morinda lucida stem bark (MLSB) was tested for its efficacy to reverse lead nitrate-induced hepatotoxicity in Wistar rats. Thirty-six female rats were assigned into six groups (n = 6). Rats in group I received 2.2 mL/kg distilled water for 28 days, those in group II received 30 mg/kg lead nitrate for 14 days while those in groups III to VI received 30 mg/kg lead nitrate for 14 days followed by a treatment with 100, 250, 500 mg/kg BW MLSB extract and 0.2 mL/100 kg rats silymarin respectively for 14 days. They were sacrificed after 28 days after which biochemical, histological, and immunohistochemical parameters were examined. The results of this study showed a reduction of catalase and superoxide dismutase activities by lead nitrate. Deranged hepatic histomorphology was also observed intracellularly and extracellularly in lead nitrate-treated rats. Altered vimentin arrangement was also observed in lead nitrate-treated rats. However, 250 mg/kg BW dose of Morinda lucida significantly reversed some of these changes while the 500 mg had some toxic effect on liver tissue. We concluded that the extract at 250mg/kg BW dose may be a potential treatment for conditions associated with lead toxicity and other metallic particles.