Abstract
Sodium valproate (VPA) is an anti-epileptic drug, but has a strong embryotoxicity due to its induced disturbance of folate-homocysteine (Hcy) metabolism and fatty acid metabolism. The aim of the present study was to investigate whether polyunsaturated fatty acid (PUFA) intake during pregnancy can relieve the embryotoxicity of VPA. VPA (dose: 500 mg kg-1, concentration: 38.5 mg ml-1) was intraperitoneally injected into pregnant mice on day 8.5 of gestation (E8.5d). PUFA intake significantly decreased fetal mortality and NTD incidence induced by VPA: n-3 long chain PUFAs (n-3 LCPUFAs) in fish oil had the best decreasing effect, followed by C18:3n-3 in flaxseed oil and then C18:2n-6 in corn oil. VPA administration inhibited the mRNA and protein expressions of a series of enzymes involved in folate-Hcy metabolism in the liver of pregnant mice; however, it led to the mRNA and protein overexpression of these enzymes in embryos. An elevated Hcy level in embryos was observed 6 h after VPA injection. n-3 PUFA intake effectively relieved this disturbance of folate-Hcy metabolism in pregnant mice and embryos, and this relieving effect of n-3 LCPUFAs and C18:3n-3 is better than that of C18:2n-6. In addition, n-3 PUFA intake also relieved the growth retardation induced by VPA. In conclusion, PUFA intake during pregnancy can effectively decrease embryotoxicity of VPA by relieving VPA-induced disturbance of folate-Hcy metabolism in pregnant mice and embryos, and n-3 LCPUFA in fish oil had the optimal protection effect.