LAUSR

Abstract Monocrotophos is one of the extensively used organophosphorus insecticides in agriculture and animal husbandry in India. It induces neurotoxicity by inhibiting acetyl cholinesterase enzyme and elevating oxidative stress. Curcumin, dietary polyphenol, well known for its antioxidant and anti-inflammatory properties which could elicit protective effect against monocrotophos induced neurobehavioural abnormalities. Therefore this study is aimed to investigate ameliorative effect of curcumin loaded Nanoparticles on monocrotophos induced neurotoxicity. Curcumin loaded PLGA nanoformulation was prepared using nanoprecipitation technique and was characterized using zeta sizer, FTIR and NMR spectroscopy. For in-vivo study, 30 male rats were utilized. Exposure of monocrotophos was done at 2 mg/kg (p.o.) for 28 days. Curcumin bulk and cucurmin loaded Nanoparticles were administered with or without monocrotophos. Effect of monocrotophos exposure on behavioural changes was assessed by analysing spontaneous locomotor activity, motor coordination in rotarod test and contextual fear memory in passive shock avoidance paradigm. Effect on biochemical alteration in blood and brain were estimated. The average particle size of Curcumin loaded Nanoparticles was 114.9 nm and in-vitro release study suggested suitable release of Curcumin in simulated intestinal fluid. Results of in-vivo study indicated, monocrotophos exposure caused a significant increase in reactive oxygen species, thiobarbituric acid reactive substances, and intracellular free calcium levels along with altered behavioural abnormalities in locomotor activity, motor coordination, learning and memory. Decline in antioxidant defence level might suggest reduced host defence response. Treatment with curcumin alone did not significantly reversed monocrotophos induced neurotoxicity in rats. Whilst, treatment with curcumin loaded nanoparticles significantly reduced monocrotophos induced behavioural and biochemical alteration in rat brain. The outcome of the present study suggested improved efficacy of curcumin loaded nanoparticles, possibly via its enhanced bioavailability. Further alleviation of oxidative stress and intracellular free Ca2+ level might be speculated as one of the plausible neuroprotective mechanism of curcumin in this study.