Titanium dioxide and gold nanoparticles toxicity in albino rats: Biochemical, anatomical, histopathological, and immunohistochemical studies.

The current research is aimed to synthesize, characterize, investigate, and compare the effect of Gold (Au) and titanium dioxide (TiO2) nanoparticles-mediated hepatorenal toxicity in adult male albino rats demonstrating which one of them is more secure for future use. Acute toxicity and LD50 studies were assessed. For the hepatorenal toxicity study, thirty albino rats were assigned into three groups (n = 10): Group I (control) was administered distilled water, groups II (Au-NPs), Au-NPs were given daily for four weeks at oral dose of 31 mg/kg, and in group III (TiO2-NPs), TiO2-NPs were administered daily for four weeks at oral dose of 33 mg/kg. After the experiment was over, blood, liver, and kidney specimens were collected and processed for biochemical, anatomical, histopathological, and immunohistochemical studies. Results revealed that LD50 was found to be (310 mg/kg body weight) for Au-NPs and (330 mg/kg body weight) for TiO2 NPs. Au-NPs substantially elevated the concentrations of serum hepatic markers (AST and ALT) and serum kidney markers (urea and creatinine) compared to TiO2 NPs. Hepato-renal tissues showed increase in MDA concentration, but decreased SOD activity in Au-NPs exposed group compared to TiO2 NPs-exposed group. Macroscopically, TiO2 NPs and Au NPs-caused obvious gross effects in both hepato-renal organs compared to control group. Liver and kidney of rats administered Au-NPs showed marked histopathological alterations plus a significant increase in the caspase-3 positive renal cells and hepatocytes compared to TiO2-NPs group. In conclusion, Au-NPs have a harmful effect on the liver and kidney functions proved by histopathological, immunohistochemical, and biochemical parameters, which was more injurious than TiO2-NPs.