Lead contamination induces neurodegeneration in prefrontal cortex of Wistar rats

Abstract

Objectives: Neurodegenerative disorders have been associated with several environmental pollutants such as heavy metals. This study aimed at investigating the neurodegenerative impact of lead concentration obtained from the waterways in Kwara State, Nigeria on Wistar rats. Methods: Twenty-first filial generation inbred adult male Wistar rats (Rattus norvegicus) with an average weight of 150–180 g were divided into two groups of ten animals. The highest mean concentration of lead obtained from the waterways of the three geographical zones of Kwara Nigeria was administered with water (0.009 mg of Pb(CH3CO2).3H2O per milliliter solution) to rats in the treatment group ad libitum for 65 days. The harvested prefrontal cortex was processed for paraffin embedding and the sections were stained for haematoxylin and eosin stain and Bielschowsky’s silver impregnation stain, and glial fibrillary acidic protein (GFAP) and inducible nitric oxide synthase (iNOS) immunohistochemistry. Results: The histochemical stainings revealed shreds of evidence of neuronal degeneration in the treatment group compared to the control group. Immunohistochemical analysis revealed marked astrocytosis, the hallmark of neuroinflammation, with induced oxidative stress in the treatment group compared to the control group. Conclusion: These results indicate lead obtained from the three geographical zones of Kwara Nigeria may have a possible pathogenic role in development of neurodegenerative disorders and emphasize the effects of exposure to this environmental pollutant.