Effects of imidacloprid on some biochemical parameters and hemocytes of Galleria mellonella

In this study, effects of sublethal concentrations of imidacloprid on antioxidant enzyme activities (superoxide dismutase and catalase), lipid peroxidation levels (malondialdehyde content), some biochemical parameters (total protein, total lipid, and total carbohydrate), and hemocytes (total hemocyte count), which is important component of cellular immune defense system of Galleria mellonella were investigated. Sublethal doses of imidacloprid (0.25, 0.50, 0.75 and 1.00 µg) were injected to G. mellonella larvae and the effects were investigated at 24, 48, 72 and 96 hour periods. Injection of larvae to 0.75 and 1.00 µg imidacloprid caused a significant decrease in protein content at 96 h. Lipid and carbohydrate contents were significantly reduced at all periods when compared to the control. Antioxidant enzyme activities and malondialdehyde content increased after the imidacloprid injection. Total hemocyte counts in experimental larvae were significantly decreased compared to the control. Consequently, imidacloprid caused the changes of cellular immune and antioxidant enzyme system, and energy metabolism of G. mellonella, possibly by leading to damage of oxidative balance and homeostasis.