Is chronic rapeseed oil diet more neuroprotective than chronic corn/sunflower diet?

Evaluation by audiogenic seizure test in magnesium-deficient mice (MDDAS)

¹ Neuropharmacology Laboratory, Faculty of Pharmacy, Châtenay Malabry
² Toxicology Laboratory, Faculty of Pharmacy, Illkirch
³ NMPA, Univ ParisXI, Orsay
⁴ INSERM UNIV 045131, Neuropaediatrics, Salengro Hospital, CHRU, Lille
⁵ ONIDOL, Paris, France

^* nicole.pages4@hotmail.fr

Abstract

Polyunsaturated fatty acids (PUFA) and specifically omega3 have been shown to exert a potent protecting effect on both cardiac and neuronal functions. Rapeseed oil contains 9% of alphalinolenic acid (18-3n-3, ALA), whereas corn and sunflower oils (18:2n-6, linoleic acid rich) do not. The aim of the present study was to compare in mice the putative protective effects of ALA, by testing two chronic diets containing either rapeseed oil (ALA rich) or a corn/sunflower blend (devoided of ALA) using an epilepsy model, allowing the detection of neurotoxic or neuroprotective activities: the MDDAS test (Magnesium Deficiency-Dependent Audiogenic Seizure test). After a 30 day-Mg-deprivation period, neuronal hyperexcitability appeared only in the corn/sunflower fed group, suggesting a protecting effect of the rapeseed oil. The number of convulsive mice was twice reduced in the rapeseed group and all of them recovered whereas in the corn/sunflower group all the mice had seizures and 43% died. The pattern of seizures with the rapeseed diet showed an increase in the first two step durations (latency and wild running), and a non significant slight decrease in the third (convulsions) and the fourth (recovery) ones. These results suggest a GABAergic-like effect. The increases in the first 2 phases were also indicative of a likely effect on Na+ channels, which was also observed using the maximum electroshock seizure test. These preliminary results indicate that adapted chronic dietary intake of rapeseed oil, an ALA rich monounsaturated oil, could help to control neuronal disorders as here shown in our model of magnesium-deficient mice.