Protective Effects of Quercetin on Clothianidin-Induced Liver Damage in the Rat Model

Clothianidin (CTD) is a member of the neonicotinoid group of insecticides. This study was performed to determine the effect of quercetin on clothianidin-induced liver injury (CTD) in rats. Rats were randomly assigned to a normal control (saline), a CTD control-treated group (20 mg/kg) every 3 days for 21 days, and CTD + quercetin-treated groups (2.5, 5, and 10 mg/kg) for 35 days intraperitoneally. Enzyme activity, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), was measured by spectrophotometry in serum samples by an automatic biochemical analyzer using commercial kits. Total antioxidant capacity (TAC), malondialdehyde (MDA), and nitrate-nitrite were measured in homogeneous liver tissue samples of animals. A significant increase in ALT and AST enzyme activity was observed in the CTD group in comparison with that of the control groups. In the clothianidin + quercetin (10 mg/kg) group, the ALT and AST enzyme levels decreased compared to the clothianidin control group significantly (P < 0.05). The MDA value of the liver increased in the clothianidin-treated group compared to that of the control groups (P < 0.05). Decreased tissue TAC level was observed in the CTD-treated group in comparison with that of the control groups (P < 0.05). The MDA level of the liver decreased in the clothianidin + quercetin (10 mg/kg) group compared to that of the CTD control group (P < 0.05). Quercetin significantly raised the level of TAC in the liver tissue of the clothianidin + quercetin (10 mg/kg) treated group compared to that of the clothianidin control group (P < 0.05). Liver nitrate-nitrite measurement showed a significant increase in the clothianidin group compared to that of the normal control group (P < 0.05). Nitrate-nitrite level in the liver was decreased in clothianidin + quercetin (10 mg/kg) compared to that of the clothianidin control group significantly (P < 0.05). Histopathological investigation revealed that contact to the CTD induced tissue disorganization and inflammatory cell infiltration, but minor histopathological alterations in the liver tissues of rats treated with CTD and quercetin (10 mg/kg) were detected.