Fig. 2
Hepatotoxicity induced by TiO2 NPs via oral exposure for 90 days. a Schematic diagram for oral administration of TiO2 NPs (0, 2, 10, and 50 mg/kg/d) in SD rats for 90 d. Hepatotoxicity was evaluated by serum biochemical indicators related to liver damage and histopathological observation. The serum levels of TBIL (b), TP (c), ALB (d), GLB (e), ALT (F), and AST (g) in rats were detected after TiO2 NPs treatment for 90 consecutive days. h and i were representative pathological images of HE staining under light microscopy (magnification: 20×). Fatty degeneration of hepatocytes, which appeared as fat vacuoles (black arrow), was evident in the 50 mg/kg BW TiO2 NPs treated group. j and k were representative TEM images of liver tissues (magnification: 8000×). Under TEM, it was observed that vacuolation of mitochondria (yellow arrows) around nuclei (red arrow) in hepatocytes was obvious in the 50 mg/kg BW TiO2 NPs treated group. Significant difference compared with the control group (∗ p < 0.05). TBIL: total bilirubin, TP: total protein, ALB: albumin, GLB: globulin, ALT: alanine aminotransferase, AST: aspartate aminotransferase