Effect of dietary alpha-linolenic acid intake on incorporation of docosahexaenoic and arachidonic acids into plasma phospholipids of term infants

• Published in: Lipids Vol. 31; no. 1Part2; pp. S131 - S135
• Main Authors: Sauerwald, T.U, Hachey, D.L, Jensen, C.L, Chen, H.M, Anderson, R.E, Heird, W.C
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer‐Verlag 01.01.1996
• Subjects: alpha-Linolenic Acid - metabolism; alpha-Linolenic Acid - pharmacology; Arachidonic Acid - metabolism; diet-related diseases; Dietary Fats, Unsaturated - metabolism; Dietary Fats, Unsaturated - pharmacology; Docosahexaenoic Acids - metabolism; Fatty Acids, Omega-3 - metabolism; Fatty Acids, Omega-6; Fatty Acids, Unsaturated - metabolism; human nutrition; Humans; Infant, Newborn - blood; nutrition physiology; Oxidation-Reduction; Phospholipids - blood
• ISSN: 0024-4201; 1558-9307
• DOI: 10.1007/BF02637064

The fractional conversion rates of plasma phospholipid α‐linolenic acid (18:3n‐3) and linoleic acid (18:2n‐6) to docosahexaenoic acid (22:6n‐3) and arachidonic acid (20:4n‐6), respectively, and the fractional rates of incorporation of 22:6n‐3 and 20:4n‐6 into plasma phospholipids were determined in 27 healthy 3‐wk‐old term infants who had received formulas with ≈16% of fat as 18:2n‐6 and 0.4% (n=6), 1.0% (n=11), or 3.2% (n=10) as 18:3n‐3 from birth. The infants were given a single dose of both [U‐13C] 18:2n‐6 and [U‐13C]18:3n‐3 with a feeding, and blood samples were collected 8, 12, and 24 h afterward for determination of the isotopic enrichments of the [M+18] isotopomers of plasma phospholipid fatty acids by negative chemical ionization gas chromatography/mass spectrometry. A simple precursor/product compartmental model was used to estimate fractional rates of conversion and incorporation. All infants converted 18:3n‐3 to 22:6n‐3 and 18:2n‐6 to 20:4n‐6. Although the fractional rate of conversion of 18:3n‐3 to 22:6n‐3 did not differ among groups, the fractional rate of incorporation of 22:6n‐3 into the plasma phospholipid fraction was greater in infants who received 3.2% vs. 0.4% or 1.0% 18:3n‐3 (4.1±2.2 vs 1.6±1.5 or 2.0±1.0% of the plasma phospholipid 22:6n‐3 pool daily). The fractional rate of conversion of 18:2n‐6 to 20:4n‐6 was less in infants who received the 3.2% 18:3n‐3 intake (0.4±0.3% of the plasma phospholipid 18:2n‐6 pool daily vs. 1.1±0.7% and 0.8±0.5% in those who received 0.4 and 1.0% 18:3n‐3, respectively). The fractional rate of incorporation of 20:4n‐6 into plasma phospholipid also was less in the 3.2% vs. the 0.4 and 1.0% 18:3n‐3 groups (2.7±1.4% vs. 5.9±2.6 and 4.4±1.7%, respectively, of the plasma phospholipid 20:4n‐6 pool daily).