不同泌乳期人乳磷脂成分的研究

Study on the phospholipid composition of human milk at different lactation stages

目的·获得上海地区部分人乳磷脂成分的最新数据,比较不同泌乳期人乳磷脂成分的差异。方法·招募上海交通大学医学院附属新华医院产科2016年4—7月足月分娩的健康产妇。采集第3日的初乳、第10日的过渡乳、第45日的成熟乳,Folch法提取人乳脂肪后经固相萃取分离磷脂,用高效液相色谱-可变波长检测器对磷脂酰乙醇胺、磷脂酰胆碱及鞘磷脂进行定量分析。采用单因素方差分析和Games-Howell检验比较不同泌乳阶段人乳中磷脂成分的差异。结果·入选能提供至少1份母乳的乳母100名,共收集初乳70份、过渡乳96份、成熟乳82份。成熟乳总磷脂含量平均为(281.93±118.54)μg/g,明显低于初乳的(381.99±205.90)μg/g;在泌乳期的各个阶段,磷脂酰胆碱相对含量均最高(53.74%~59.36%),鞘磷脂相对含量其次(28.12%~32.74%);随着泌乳期的延长,磷脂酰乙醇胺相对含量恒定(P=0.617),磷脂酰胆碱相对含量逐渐减少(P=0.000),而鞘磷脂相对含量逐渐增加(P=0.000)。结论·鞘磷脂和磷脂酰胆碱是人乳磷脂的主要成分;人乳磷脂含量随泌乳期延长而改变,成熟乳磷脂总量低于初乳和过渡乳;磷脂酰乙醇胺相对含量在各泌乳阶段保持一致,磷脂酰胆碱相对含量逐渐减少,而鞘磷脂相对含量逐渐增加。

Objective · To obtain the latest data on phospholipid composition of human milk in Shanghai and compare the differences in phospholipid composition at different lactation stages. Methods · Healthy postpartum women who delivered full-term infants in the Obstetrical Department of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine between April and July, 2016 were enrolled. The colostrum, transitional milk, and mature milk were collected at Day 3, 10, and 45 after delivering babies, respectively. Human milk fat was extracted with Folch’s method and phospholipids were separated with solid phase extraction （SPE）. The phosphatidylethanolamine, phosphatidylcholine, and sphingomyelin were quantitatively analyzed with HPLC/VWD. The differences in phospholipid composition at different lactation stages were compared with univariate analysis of variance and GamesHomell test. Results · One hundred women who provided at least one breast milk sample were enrolled. A total of 70 colostrum samples, 96 transitional milk samples, and 82 mature milk samples were collected. The total phospholipid content of mature milk [（281.93±118.54） μg/g] was significantly lower than that of colostrum [（381.99±205.90） μg/g]. At all lactation stages, the relative content of phosphatidylcholine was the highest （53.74%-59.36%）, followed by sphingomyelin （28.12%-32.74%）. The relative content of phosphatidylethanolamine was constant （P=0.617）, the relative content of phosphatidylcholine gradually decreased （P=0.000）, and that of sphingomyelin gradually increased （P=0.000） during the lactation. Conclusion · Sphingomyelin and phosphatidylcholine are major components of human milk phospholipids. The amount of phospholipids varies during the lactation. The total amount of phospholipids is lower in mature milk than in colostrum and transitional milk. The relative content of phosphatidylethanolamine is consistent at all lactation stages, the relative content of phosphatidylcholine gradually decreases, and that of sphingomyelin gradually increases.