Pita M L, Girón M D, Pérez-Ayala M, DeLucchi C, Martínez Valverde A, Gil A
Department of Biochemistry, University of Granada, Spain.
Clin Physiol Biochem. 1989;7(5):238-48.
Diet and postnatal age effect the fatty acid composition of plasma and tissue lipids. This work was designed as a transversal study to evaluate the changes in the fatty acid composition of plasma phospholipids, cholesteryl esters, triglycerides and free fatty acids in preterm infants (28-35 weeks gestational age), fed human milk (HM) and milk formula (MF) from birth to 1 month of life. Sixteen blood samples were obtained from cord, and 19 at 6-8 h after birth, 14 at 1 week and 9 at 4 weeks from HM-fed infants and 18 at 1 week and 14 at 4 weeks from MF-fed ones. Groups had similar mean birth weight, gestational age and sex ratio. The MF provided 69 kcal/dl and contained 16% of linoleic acid and 1.3% of alpha-linolenic acid on the total fat. Plasma lipid fractions were extracted and separated by thin-layer chromatography and fatty acid methyl esters were quantitated by gas liquid chromatography. In plasma phospholipids, linoleic acid (18:2 omega 6) continuously increased from birth to 1 month of age, but no changes were seen as related to type of diet; polyunsaturated fatty acids greater than 18 carbon atoms of both the omega 6 and omega 3 series (PUFA omega 6 greater than 18 C and omega 3 greater than 18 C) dropped from birth to 1 week and continued to decrease in MF-fed infants until 1 month; eicosatrienoic (20:3 omega 6), arachidonic (20:4 omega 6) and docosahexaenoic (22:6 omega 3) were the fatty acids implicated. In cholesteryl esters palmitoleic (16:1 omega 7) and oleic (18:1 omega 9) acids decreased from birth to 1 month and linoleic acid increased and arachidonic acid dropped, especially in MF fed infants. In triglycerides, palmitic, palmitoleic and stearic acid (18:0) decreased during the first month of life; oleic acid remained constant and linoleic acid increased in all infants, but arachidonic acid decreased only in those fed formula. Free fatty acids showed a similar behavior in fatty acids and in plasma triglycerides. Preterm neonates seem to have special requirements of long-chain PUFA and adapted MF should contain these fatty acids in similar amounts to those of HM to allow the maintenance of an adequate tissue structure and physiology.
饮食和出生后年龄会影响血浆和组织脂质的脂肪酸组成。本研究设计为一项横向研究，旨在评估胎龄28 - 35周的早产儿从出生到1月龄期间，食用母乳（HM）和配方奶（MF）时血浆磷脂、胆固醇酯、甘油三酯和游离脂肪酸的脂肪酸组成变化。从食用母乳的婴儿脐带处采集16份血样，出生后6 - 8小时采集19份，1周时采集14份，4周时采集9份；从食用配方奶的婴儿1周时采集18份，4周时采集14份。各群组的平均出生体重、胎龄和性别比相似。配方奶每分升提供69千卡热量，总脂肪中含有16%的亚油酸和1.3%的α-亚麻酸。血浆脂质组分通过薄层色谱法提取和分离，脂肪酸甲酯通过气相色谱法定量。在血浆磷脂中，亚油酸（18:2 ω6）从出生到1月龄持续增加，但与饮食类型无关；ω6和ω3系列中碳原子数大于18的多不饱和脂肪酸（PUFA ω6大于18C和ω3大于18C）从出生到1周下降，在食用配方奶的婴儿中持续下降至1月龄；二十碳三烯酸（20:3 ω6）、花生四烯酸（20:4 ω6）和二十二碳六烯酸（22:6 ω3）是相关脂肪酸。在胆固醇酯中，棕榈油酸（16:1 ω7）和油酸（18:1 ω9）从出生到1月龄减少，亚油酸增加，花生四烯酸下降，尤其是在食用配方奶的婴儿中。在甘油三酯中，棕榈酸、棕榈油酸和硬脂酸（18:0）在出生后第一个月减少；油酸保持不变，亚油酸在所有婴儿中增加，但花生四烯酸仅在食用配方奶的婴儿中减少。游离脂肪酸在脂肪酸和血浆甘油三酯中的表现相似。早产新生儿似乎对长链多不饱和脂肪酸有特殊需求，适配的配方奶应含有与母乳相似量的这些脂肪酸，以维持适当的组织结构和生理功能。
