Oral administration of docosahexaenoic acid/eicosapentaeinoic acids is not anticonvulsant in rats: implications for translational research.

Omega-3 and omega-6 poly-unsaturated fatty acids (PUFAs) are dietary fatty acids that are involved in a myriad of physiological processes in the brain. Although experimental data have shown that PUFAs have anticonvulsant properties, the outcomes of clinical trials have been controversial. Docosahexaenoic acid (DHA) is a PUFA which has been reported to exert anticonvulsant effects. Here we studied anticonvulsant potential of a mixture of enriched n-3 PUFA upon their oral administration in rats. We did not observe an anticonvulsant effect of n-3 PUFA in the i.v. pentylentetrazol threshold test. n-3 PUFA component was increased in the plasma of rats treated with the eicosapentaenoic acid (EPA)/DHA mix (275 mg/kg/d/400 mg/kg/d) due to the increase of both DHA and EPA. We also found modification of PUFA composition in the brain. Despite PUFA profiles modified both in plasma and in the brain, we did not find any anticonvulsant effect of orally administered DHA. Further studies are needed to define the type and the amount of fatty acids that would possess anticonvulsant properties. As the existing literature suggests that the route of administration of PUFA may be crucial, future studies should involve oral administration to provide relevant clinical information.