Cerium Oxide Nanoparticle Effects on Paraoxonase-1 Activity and Oxidative Toxic Stress Induced by Malathion: A Potential Antioxidant Compound, Yes or No?

Abstract

Cerium oxide nanoparticles (CeNPs) are one of the most widely used and important nanoparticles in addition to possessing strong antioxidative properties and inhibiting free radicals. Paraoxonase-1 (PON1) is one of the enzymes that protect the body against damage caused by oxidative stress. The purpose of this study was to investigate the effect of CeNPs on the activity of PON1 as well as biomarkers of oxidative stress in the toxicity of malathion. 48 Albino Wistar male rats with weight range of 180-250g were randomly divided into 8 groups, Group 1: healthy control, injection of normal saline, Group 2: administration by the malathion 100mg/kg/day, Group 3: treated with CeNPs 15mg/kg/day, Group 4: treated with CeNPs 30mg/kg/day, Group 5: combination of malathion with dose of 100mg/kg/day and CeNPs 15mg/kg, Group 6: combination of malathion with dose of 100mg/kg/day and CeNPs 30mg/kg for 14days and 24h after termination of treatment period, serum and liver tissue samples were collected from all rats. Biochemical test of PON1 activity, oxidative stress biomarkers including total antioxidant capacity (TAC), lipid peroxidation (LPO), total thiol groups (TTG), were carried out. Malathion reduced plasma TTG levels, TAC and increased LPO in malathion group. However, CeNPs increased TTG, TAC and reduced PON1 activity. Results showed that CeNPs alone had antioxidant properties while with malathion it shows different properties.