Department of Pediatrics, Institute of Pediatrics, Faculty of Medicine, Jagiellonian University Medical College, Krakow, Poland -
Department of Clinical Biochemistry, Institute of Pediatrics, Faculty of Medicine, Jagiellonian University Medical College, Krakow, Poland.
Minerva Pediatr (Torino). 2022 Aug;74(4):416-420. doi: 10.23736/S2724-5276.18.05057-0. Epub 2018 Jul 2.
Irisin is a newly discovered myokine with antiobesity properties. The delivery of irisin with the breast milk or formula is an emerging concept that myokine present at human milk influences postnatal energy balance and developmental parameters. The aim of the study was to evaluate irisin concentration in breast milk of mothers with term and preterm babies and in infant formulas.
A total of 49 lactating mothers were enrolled in the study: 31 mothers of very low birth weight preterm infants and 18 mothers of term infants. Milk samples were collected twice: during the first week after delivery and after 4 weeks of delivery. Irisin concentration was determined using ELISA kits both in human milk and in samples of 14 different infant formulas.
There were no differences in milk irisin levels between preterm and full-term milk samples during both the 1 and the 4 week after delivery. There were also no differences in irisin concentration between transitional milk and mature milk in both tested groups. Irisin concentrations in preterm and full-term milk were significantly higher than in formulas for 30 days period after delivery. A significant increase of irisin concentration in natural milk 4 weeks postdelivery in comparison to 1 week after delivery was observed (mean difference 0.362 µg/mL; P=0.0063).
This study provides evidence that irisin is present in infant formulas, although in less amount than in human milk. Further research is needed to assess, if children fed with infant formulas may disadvantage from lower irisin supply.
鸢尾素是一种新发现的具有抗肥胖特性的肌肉因子。将鸢尾素与母乳或配方奶一起输送是一种新兴概念，即母乳中存在的肌肉因子会影响产后能量平衡和发育参数。本研究的目的是评估足月和早产儿母亲的母乳以及婴儿配方奶中的鸢尾素浓度。
共有 49 名哺乳期母亲参与了这项研究：31 名极低出生体重早产儿的母亲和 18 名足月婴儿的母亲。在分娩后第 1 周和第 4 周收集两次奶样。使用 ELISA 试剂盒测定人乳和 14 种不同婴儿配方奶样本中的鸢尾素浓度。
在分娩后第 1 周和第 4 周，早产儿和足月母乳样本中的乳汁鸢尾素水平没有差异。在两个测试组中，过渡奶和成熟奶之间的鸢尾素浓度也没有差异。与配方奶相比，早产儿和足月母乳在分娩后 30 天内的鸢尾素浓度明显更高。与分娩后第 1 周相比，自然母乳在分娩后第 4 周的鸢尾素浓度显著升高（平均差异 0.362µg/mL；P=0.0063）。
本研究提供的证据表明，鸢尾素存在于婴儿配方奶中，尽管其含量低于母乳。需要进一步研究评估，以确定食用婴儿配方奶的儿童是否可能因鸢尾素供应较低而处于不利地位。
