Zinc oxide nanoparticles hepatotoxicity: Histological and histochemical study

- Exposure to ZnO NPs produces hepatic histological and histochemical alterations.
- Exposure to ZnO NPs induces necrosis, degeneration and apoptosis of hepatocytes.
- Exposure to ZnO NPs causes partial hepatic glycogen depletion and hemosidosis.
- Exposure to ZnO NPs may affect the structure and function of the liver.

Zinc oxide nanoparticles (ZnO NPs) are widely used in industry and cosmetic products with promising investment in medical diagnosis and treatment. However, these particles may reveal a high potential risk for human health with no information about hepatotoxicity that might be associated with their exposure. The present work was carried out to investigate the histological and histochemical alterations induced in the hepatic tissues by naked 35 nm ZnO NPs. Male Wistar albino rats were exposed to ZnO NPs at a daily dose of 2 mg/kg for 21 days. Liver biopsies from all rats under study were subjected to histopathological examinations. In comparison with the control rats, the following histological and histochemical alterations were demonstrated in the hepatic tissues of rats exposed to ZnO NPs: sinusoidal dilatation, Kupffer cells hyperplasia, lobular and portal triads inflammatory cells infiltration, necrosis, hydropic degeneration, hepatocytes apoptosis, anisokaryosis, karyolysis, nuclear membrane irregularity, glycogen content depletion and hemosidrosis. The findings of the present work might indicate that ZnO NPs have potential oxidative stress in the hepatic tissues that may affect the function of the liver. More work is needed to elucidate the toxicity and pathogenesis of zinc oxide nanoparticles on the vital organs.