Studies on acute and subacute toxicity of thiacloprid and its amelioration by resveratrol in male rats
Abstract
Thiacloprid, a neonicotinoid insecticide is known to target the nicotinic acetyl choline receptors (nACHRs) in insects, and potentially in mammals. The aim was to ascertain the maximum tolerated dose (MTD) and to investigate the effect of acute (24 h) and subacute (28 days) toxicity of thiacloprid and its amelioration by resveratrol in male Wistar rats. The MTD of thiacloprid was determined to be 345 mg/kg b wt. orally in male rats. Thiacloprid produced typical signs and symptoms of toxicity viz. piloerection, decreased motility and reactivity, poor reflexes, spastic gait, spasmodic state, convulsions, tremors, tachypnoea, dyspnoea, labored breathing, diarrhoea, narrowed palpebral fissure, closed eyelids, red incrusted snout. Thiacloprid treatment resulted in decreased body weight gain in 28 days study which was restored by resveratrol co-treatment. No significant changes were observed in relative organ weight 24 h study whereas significant changes were observed in relative organ weight in liver kidney and spleen in male Wistar rats in 28 days study which was restored with resveratrol co-treatment. Thiacloprid treatment produced significant changes in oxidative stress markers viz. malondialdehyde, myeloperoxidase, catalase, reduced glutathione, glutathione peroxidase, nitric oxide, total thiols and superoxide anion radical generation which were significantly restored by resveratrol co-treatment. Liver and kidney function tests viz. ALT, AST, GGT, BUN, creatinine, were significantly increased while reduction in total protein levels were resulted from thiacloprid treatment which were significantly restored with resveratrol cotreatment in rats. Thiacloprid treatment resulted in significant reduction in T3, and T4 levels and increase in TSH levels in 24 hours study whereas a significant increase in T3, and T4 levels and reduction in TSH levels in rats were observed in 28 days study which were significantly restored by resveratrol co-treatment. No significant changes were observed in hematological profile in 24 h study whereas a decline in Hb, TEC, HCT and MCV and increase in ESR and TLC due to neutrophilia and lymphocytosis was observed in rats in 28 days study. Histopathological alterations were observed in kidney, liver, brain and spleen in both acute and subacute studies due to thiacloprid exposure which were attenuated by resveratrol co-treatment. The study revealed that thiacloprid possesses mild to moderate toxicity potential for hepatic, renal, CNS and hematological profile of adult male rats. Resveratrol possesses potential to sufficiently ameliorate the toxicity produced by thiacloprid and as such do not have any toxic effect at therapeutic doses in adult male wistar rats.