Abstract: Titanium dioxide nanoparticles (TiO2 NPs) are manufactured worldwide in large quantities for use in a
wide range of applications including pigment, plastics, papers, inks, food colorants, toothpastes and cosmetic
manufacturing. Milk thistle is a herbal supplement used to treat liver and biliary disorders. Silymarin, an active
ingredient of Milk thistle, is a strong antioxidant that promotes liver cell regeneration and stabilizes cell membranes.
Our aims were to investigate the biochemical and histological changes in the liver after administration of different
doses of TiO2 NPs and if there is a protective role of Milk thistle against these changes. The present study was
carried out on fifty adult male rats divided into five groups: control group, group IIa injected by 100mg/kg TiO2,
group IIb treated by oral Milk thistle during injection by 100mg/kg TiO2, group IIIa injection by 150mg/kg TiO2 and
group IIIb treated by oral Milk thistle during injection by 150mg/kg TiO2. There were a decrease in the body weight
and an increase in the coefficients of the liver in all treated groups. Changes in hepatocytes include; ballooned
vacuolated cytoplasm and congested dilated portal vessels with inflammatory cellular infiltrations. Hepatocytes
showed early signs of apoptosis and degeneration with nuclear changes. There were excessive amount of collagen
fibers and marked depletion in the amount of glycogen. The histologic alterations observed might be an indication of
hepatocyte injury due to TiO2 NPs toxicity that interacts with proteins and enzymes in hepatic tissue. This interferes
with antioxidant defense mechanisms and generation of reactive oxygen species induce hepatocytes apoptosis and
generates inflammatory process resulting in cellular degeneration. These changes were improved by Milk thistle
supplement as increase body weight, normal coefficient and normal morphology of the liver.
[Eman E. Abu-Dief, Kamal M. Khalil, Hekmat O. Abdel-Aziz, Eman K. Nor-Eldin, Eman E. Ragab. Histological
effects of Titanium dioxide nanoparticles in Adult male albino rat liver and possible prophylactic effects o