Effect of glycyrrhizic acid on titanium dioxide nanoparticles-induced hepatotoxicity in rats.

Many recent studies demonstrate that most nanoparticles (NPs) have an adverse or toxic action on liver. The aim of this study was to investigate the hepatoprotective effect of glycyrrhizic acid (GA) against hepatic injury induced by titanium dioxide nanoparticles (NTiO2) in rats. Thirty-two Wistar rats were randomly divided into 4 groups. NTiO2-intoxicated rats received 300 mg/kg of NTiO2 for 14 days by gavage method. Protection group pretreated with GA for 7 days before NTiO2 administration. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were detected as biomarkers in the blood to indicate hepatic injury. Product of lipid peroxidation (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were evaluated for oxidative stress in hepatic injury. Light microscopy for histopathological studies and TUNEL assay was also done. Administration of NTiO2 induced a significant elevation in plasma AST, ALT and ALP. In the liver, NTiO2 increased oxidative stress through the increase in lipid peroxidation and decrease in SOD and GPx enzymes. Histopathological studies showed that treatment with NTiO2 caused liver damage including centrilobular necrosis, which was accompanied by congestion and accumulation of inflammatory cells. Apoptotic index was also significantly increased in this group. Pretreatment of GA significantly decreased ALT, AST and ALP, attenuated the histopathology of hepatic injury, decreased apoptotic index, ameliorated oxidative stress in hepatic tissue, and increased the activities of SOD and GPx. These findings indicate that GA effectively protects against NTiO2-induced hepatotoxicity. GA has a potent protective effect against the NPs induced hepatotoxicity and might be clinically useful.