Docosahexaenoic acid accumulation in the prenatal brain: prooxidant and antioxidant features.
Docosahexaenoic acid (DHA; 22:6n-3) is the major polyunsaturated fatty acid (FA) in the adult rat brain and it accumulates significantly more than any other FA prior to birth. Under normal nutritional conditions, fetal-brain DHA accumulation is substantial, with a "DHA accretion spurt" being demonstrated in the last period of gestation. Under stress conditions, this spurt may be harmful owing to an increase in multiple double-bond targets for lipid peroxidation. The "DHA accretion spurt" is supported by the maternal supply of DHA or its precursor. Under maternal dietary n-3 FA deficiency, DHA content in the fetal brain can be restored by direct intraamniotic injection of mM concentrations of ethyl-DHA (Et-DHA). This approach may hold a potential advantage in the event of maternal-fetal insufficiency, a stress that may cause intrauterine growth retardation. It also revealed a potential beneficial effect after in utero ischemic stress; brain slices from Et-DHA-treated fetuses formed less oxidation products, as detected by thiobarbituric acid (TBA), compared to controls. Furthermore, brain-lipid extracts from Et-DHA but not ethyl-oleate treated fetuses, exhibited hydroxyl radical scavenging activity, as demonstrated by electron spin-resonance technique. Part of the beneficial effect of Et-DHA administration on the fetal brain may be attributed to enhanced free-radical scavenging capability, a phenomenon not directly related to vitamin E or lipid-soluble antioxidant levels.
Yavin
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E
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel. ephraim.yavin@weizmann.ac.il
Glozman
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S
Green
P
P
D000818:Animals; D001921:Brain / Q000196:embryology / Q000378:metabolism*; D004041:Dietary Fats / Q000493:pharmacokinetics; D019587:Dietary Supplements; D004281:Docosahexaenoic Acids / Q000378:metabolism* / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D005231:Fatty Acids, Unsaturated / Q000493:pharmacokinetics; D005260:Female; D005317:Fetal Growth Retardation / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D007511:Ischemia / Q000378:metabolism; D015227:Lipid Peroxidation; D008431:Maternal-Fetal Exchange; D019301:Oleic Acid / Q000494:pharmacology; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism; D010920:Placenta / Q000098:blood supply; D010938:Plant Oils / Q000008:administration & dosage / Q000493:pharmacokinetics; D011247:Pregnancy; D051381:Rats; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
D004041:Dietary Fats; D005231:Fatty Acids, Unsaturated; D016166:Free Radical Scavengers; D010714:Phosphatidylethanolamines; D010718:Phosphatidylserines; D010938:Plant Oils; D017392:Thiobarbituric Acid Reactive Substances; D004281:Docosahexaenoic Acids; D019301:Oleic Acid