Malathion is one of the most used organophosphorus pesticides that is used for many reasons such as agriculture and industry. Human exposure to malathion may occur through various means, such as eating food that has been treated with it. Malathion not only increases oxidative stress but also decreases the antioxidant capacity. Curcumin is a powerful antioxidant with many pharmacological actions. Curcumin can act as a free radical scavenger and inhibit the activation and nuclear translocation of NF-κB. Curcumin could combat the lipid peroxidation and antioxidant depletion that trigger the apoptotic pathways. This study aims to examine the antioxidant, anti-inflammatory, and antiapoptotic effects of curcumin. Twenty-four Sprague Dawley rats were divided into four groups (six rats each): control, curcumin, malathion, and malathion + curcumin groups. At the assigned time, blood samples were used for the assessment of serum creatinine, and the kidneys were excised and washed; parts of them were used for the assessment of total oxidant status (TOS), oxidative stress index (OSI), the oxidative stress marker malondialdehyde (MDA), total antioxidant capacity (TAC), and glutathione (GSH) activity, other parts were fixed in formalin for further staining. Histopathological evaluation was performed for the fixed specimens after staining with H&E, sirus red, and the immunohistochemical staining for NF-κβ, TNF-α, Caspase-3, Nrf2, and HO-1. Curcumin significantly decreases the serum creatinine after malathion exposure and significantly restores the oxidant/antioxidant balance by increasing TAC and GSH and decreasing TOS, OSI, and MDA. Curcumin exerts its reno-protective effect and restores the histological architecture of the kidney by downregulating the immune expression of NF-κβ, TNF-α, and Caspase-3 and upregulating the expression of Nrf2 and HO-1. This study concluded that curcumin protects against nephrotoxicity caused by malathion by exerting its antioxidant, anti-inflammatory, and anti-apoptotic capabilities.
Keywords: antioxidant; apoptosis; curcumin; malathion; renal toxicity.