title: Bioequivalence of dietary alpha-linolenic and docosahexaenoic acids as sources of docosahexaenoate accretion in brain and associated organs of neonatal baboons.
abstract: The dietary bioequivalence of alpha-linolenic (LNA) and docosahexaenoic acids (DHA) as substrates for brain and retinal n-3 fatty acid accretion during the brain growth spurt is reported for neonatal baboons who consumed a long-chain-polyunsaturate free commercial human infant formula with a n-6/n-3 ratio of 10:1. Neonates received oral doses of 13C-labeled fatty acids (LNA*) or (DHA*) at 4 wk of age, and at 6 wk brain (occipital cortex), retina, retinal pigment epithelium, liver, erythrocytes, and plasma were analyzed. In the brain, 1.71% of the preformed DHA* dose was detected, whereas 0.23% of the LNA* dose was detected as DHA*, indicating that preformed DHA is 7-fold more effective than LNA-derived DHA as a source for DHA accretion. In LNA*-dosed animals, DHA* was greater than 60% of labeled fatty acids in all tissues except erythrocytes, where docosapentaenoic acid was 55%. Estimates using dietary LNA levels as tracees indicate that brain turnover of DHA is less than 5% per week between weeks 4 and 6 of life. For retina and retinal pigment epithelium, preformed DHA was at levels 12-fold and 15-fold greater than LNA-derived DHA. Liver, plasma, and erythrocytes ratios were 27, 29, and 51, respectively, showing that these pools do not parallel tissue metabolism of a single dose of omega-3 fatty acids. The distributions of labeled fatty acids for LNA*-dosed animals were similar, in the order DHA > DPA > EPA > LNA, except for erythrocytes where docosapentaenoic acid predominated. These are the first direct measurements of the bioequivalence of DHA and LNA in neonatal primate brain and associated tissues.
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Su
authors.forename: L
authors.initials: L
authors.lastname: Bernardo
authors.forename: M
authors.initials: M
authors.lastname: Mirmiran
authors.forename: X H
authors.initials: XH
authors.lastname: Ma
authors.forename: T N
authors.initials: TN
authors.lastname: Corso
authors.forename: P W
authors.initials: PW
authors.lastname: Nathanielsz
authors.forename: J T
authors.initials: JT
authors.lastname: Brenna
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn; D004281:Docosahexaenoic Acids / Q000097:blood / Q000493:pharmacokinetics*; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D006801:Humans; D007225:Infant Food; D008099:Liver / Q000378:metabolism; D008297:Male; D009778:Occipital Lobe / Q000378:metabolism*; D009928:Organ Specificity; D010215:Papio; D010857:Pigment Epithelium of Eye / Q000378:metabolism; D012160:Retina / Q000378:metabolism; D013810:Therapeutic Equivalency; D017962:alpha-Linolenic Acid / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D017962:alpha-Linolenic Acid; D004281:Docosahexaenoic Acids