Abstract:
Imidacloprid is a systemic neonicotinoid insecticide widely used to combat agricultural pests and flea infestations
in dogs and cats. Despite its low toxicity to mammals, imidacloprid is reported to cause male reproductive
toxicity. This study evaluated the cytotoxic effects of 75–800 μM imidacloprid on a rat Leydig cell line (LC-540).
The effect of exposure to 300, 400, and 500 μM imidacloprid on selected cytoskeletal proteins, mitochondrial
morphology, lysosomal acidity, and ultrastructure were investigated. Cell viability was markedly reduced after
48 and 72 h of exposure to higher imidacloprid concentrations. The immunocytochemical analysis revealed that
the cytoskeletal filaments exhibited disorganization, disruption, and perinuclear aggregation in treated LC-540
cells. Ultrastructurally, cytoplasmic vacuoles, autophagic vacuoles, lysosomes, and mitochondrial damage
were detected. Changes in the mitochondrial morphology and lysosomes induced by imidacloprid were
confirmed. The cytotoxicity of imidacloprid observed in LC-540 cells might be due to its mitochondrial damage
and cytoskeletal protein disruption.
