Abstract

The objective of this study is to detect toxic effects of two different doses of nano zinc oxide (ZnO-NP) particles. Moreover, a comparative study was conducted to modulate this toxic effect by the use of two natural antioxidants vitamin E (Vit E) and α-lipoic acid (α-Lip). The results of the current study revealed that ZnO-NP treatment produced hazard effects which were confirmed by the elevation of vascular endothelium growth factor (VEGF) as well as nitric oxide levels in rat serum. Inflammatory markers, including tumor necrosis factor alpha (TNF-α), Interleukin-6 (IL-6), C-reactive protein (CRP) and IgG were also elevated in rat serum compared to control normal group. Additionally, blood glucose level, as well as serum urea, and creatinine levels were significantly increased in rats intoxicated with ZnO-NP compared to normal control group. On the other hand, reduced glutathione (GSH) level was decreased in renal tissue. These biochemical findings were supported by the histopathological examination of renal tissue and the hazardous effects were dose dependant. Treatment of rats with Vit E or α–Lip along with ZnO-NP administration significantly alleviates most of the elevated previous biochemical parameters. Histopathological examination revealed that animals that received α-Lip or Vit E along with ZnO-NP showed moderate histopathological changes in the form of shrinkage and fragmentation of moderate number of glomeruli with exfoliation of tubular epithelial cells and tubular casts in moderate number of renal tubules. It was concluded that treatment with either α-Lip or Vit E has a beneficial effect against ZnO-NP oxidative stress and related vascular complications.

Key words: C-reactive protein (CRP), interleukin-6 (IL-6), nano zinc oxide, tumor necrosis factor alpha (TNF-α), vascular endothelium growth factor (VEGF).