Chlorpyrifos with Age-Dependent Effects in Cardiac Tissue of Male Rats

Background: Age-dependent toxic effects of organophosphorus pesticides (OPs) have not been fully understood. The current study aimed to investigate the cardiotoxic damage of chlorpyrifos (CPF) by evaluating oxidative modifications in young (2-month old), middle-aged (10- month old), and aged (20-month old) rats. Objective: Five mg/kg of CPF was administered orally for 45 days to young, middle-aged, and aged male Wistar rats. In the end, animals were anesthetized and the heart of each rat was dissected for biochemical assay. Methods: Malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), total antioxidant capacity (TAC), and superoxide dismutase (SOD) were assessed in the cardiac tissue of rats. Results: The results indicated an increase in the levels of MDA and NO, and also a decline in the levels of GSH and TAC as well as a decrease in the SOD activity in the heart of aged rats compared with young rats. CPF administration deteriorated these changes in the heart of exposed rats compared with the age-matched controls. Additionally, these oxidative modifications were more severe in aged rats versus other age. Conclusion: In conclusion, advancing age may increase oxidative changes in the heart of animals exposed to CPF. It is suggested that aging can affect cardiac toxicity induced by OPs.