Department of Obstetrics, Gynecology and Maternity Care, Faculty of Health Sciences, Medical University of Bialystok, Białystok, Poland.
Chair of Obstetrics Development, Faculty of Health Sciences, Medical University of Lublin, Lublin, Poland.
Sci Rep. 2023 Dec 17;13(1):22434. doi: 10.1038/s41598-023-50124-1.
The aim of this study was to investigate factors affecting total, true protein and lactoferrin (Lf) concentrations in human milk (HM) and to evaluate the changes in protein concentrations over the course of lactation (first to sixth month postpartum). HM samples were collected from exclusively breastfeeding mothers during six time periods (1-6 months postpartum); 198 breast milk samples were collected in total. The concentrations of total and true protein in HM were determined using the MIRIS human milk analyzer (HMA). The assessment of HM protein content was also performed in skim HM samples and quantified by bicinchoninic methods with the Bicinchoninic Acid Protein Assay Kit. In turn, Lf content in skim HM samples was determined by the enzyme-linked immunosorbent assay (ELISA) in accordance with a slightly modified procedure. In the first month of lactation total protein concentration was negatively correlated with maternal pre-pregnancy BMI (r = - 0.397; p = 0.022), whereas in the third month postpartum, positive correlation with maternal age was found (r = 0.399; p = 0.021). Considering Lf concentration, in the first month of lactation, it was positively correlated with baby's birth weight (r = 0.514; p = 0.002). In the next months (from second to sixth) no relationships between Lf concentration and maternal and infants' factors were observed. The concentration of protein and Lf in HM changes dynamically throughout lactation. Maternal and infant characteristics may impact the HM protein and Lf content, especially in the first month postpartum.
本研究旨在探讨影响人乳（HM）总蛋白、真蛋白和乳铁蛋白（Lf）浓度的因素，并评估泌乳期（产后第 1 至 6 个月）内蛋白质浓度的变化。在六个时间点（产后 1-6 个月）收集了纯母乳喂养母亲的 HM 样本；共收集了 198 份母乳样本。使用 MIRIS 人乳分析仪（HMA）测定 HM 中的总蛋白和真蛋白浓度。还在脱脂 HM 样本中评估 HM 蛋白质含量，并使用 Bicinchoninic 酸蛋白测定试剂盒通过双缩脲法进行定量。反过来，通过酶联免疫吸附测定（ELISA）根据略作修改的程序测定脱脂 HM 样本中的 Lf 含量。在哺乳期的第一个月，总蛋白浓度与母亲孕前 BMI 呈负相关（r=-0.397；p=0.022），而在产后第三个月，与母亲年龄呈正相关（r=0.399；p=0.021）。考虑到 Lf 浓度，在哺乳期的第一个月，它与婴儿的出生体重呈正相关（r=0.514；p=0.002）。在下个月（第 2 至第 6 个月），未观察到 Lf 浓度与母亲和婴儿因素之间存在任何关系。HM 中蛋白质和 Lf 的浓度在整个哺乳期内动态变化。母亲和婴儿的特征可能会影响 HM 蛋白质和 Lf 的含量，尤其是在产后第一个月。
