Lactosomes: structural and compositional classification of unique nanometer-sized protein lipid particles of human milk.
Lactosomes: structural and compositional classification of unique nanometer-sized protein lipid particles of human milk.
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DOI：
10.1021/jf102495s
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发表时间：
2010-11-10
影响因子：
6.1
通讯作者：
German JB
中科院分区：
文献类型：
--
作者：
Argov-Argaman N;Smilowitz JT;Bricarello DA;Barboza M;Lerno L;Froehlich JW;Lee H;Zivkovic AM;Lemay DG;Freeman S;Lebrilla CB;Parikh AN;German JB
乳脂球（MFG）主要被认为是三酰甘油输送系统。不含三酰甘油的纳米级脂质蛋白颗粒（称为“乳糖体”）的鉴定提出了其可能功能的问题。通过慢速离心分离 MFG，通过超速离心分离乳糖体，其密度相当于从六名不同哺乳阶段志愿者的母乳中获得的血浆 HDL (d > 1.063 g/ml)。对分离的乳糖体进行了分析，并与 MFG 进行了大小分布、脂质组、蛋白质组和功能活性的比较。研究发现，来自早期乳汁（第 8 天）的乳糖体与来自 >28 天的成熟乳汁的乳糖体大小相似，平均直径约为 25 nm。总共，在 MFG 和乳糖体级分中鉴定出 97 种非冗余蛋白质，其中 46 种是 MFG 级分特有的，其中 29 种是乳糖体级分特有的。乳糖体和 MFG 级分中鉴定的蛋白质富含通过免疫调节途径鉴定的蛋白质。与充当阳性对照的富含 MFG 和 GM1 的重组高密度脂蛋白 (rHDL) 不同，乳糖体与霍乱毒素的结合能力较弱。脂质组学分析发现，与 MFG 不同，乳糖体不含三酰甘油和神经节苷脂，但富含多种磷脂。数据发现乳糖体和 MFG 之间的结构、组成和功能存在差异，表明这两种颗粒源自不同的生物合成和/或分泌途径。结果揭示了一种具有生物活性的脂质蛋白纳米级颗粒，它被分泌到乳汁中，不是为婴儿提供能量，而是发挥独特的保护和调节作用。
Milk fat globules (MFG) are accepted primarily as triacylglycerol delivery systems. The identification of nanometer-sized lipid-protein particles termed ‘lactosomes’ that do not contain triacylglycerol raises the question of their possible functions. MFGs were isolated by slow centrifugation and lactosomes were isolated by ultracentrifugation at a density equivalent to plasma HDL (d > 1.063 g/ml) from human milk obtained from six volunteers at different lactation stages. Isolated lactosomes were analyzed and compared with MFGs for their size distribution, lipidome, proteome, and functional activity. Lactosomes from early milk—day 8, were found to be similar in size as those from mature milk >28 days averaging ~25 nm in diameter. In total, 97 non-redundant proteins were identified in the MFG and lactosome fractions, 46 of which were unique to the MFG fraction and 29 of which were unique to the lactosome fraction. The proteins identified in the lactosome and MFG fractions were enriched with proteins identified with immunomodulatory pathways. Unlike MFGs and GM1 laden reconstituted high- density lipoprotein (rHDL) that served as a positive control, lactosomal binding capacity to cholera toxin was weak. Lipidomic analyses found that lactosomes were devoid of triacylglycerol and gangliosides, unlike MFGs, but rich in a variety of phospholipid species. The data found differences in structure, composition and function between lactosomes and MFG suggesting these two particles are derived from different biosynthetic and/or secretory pathways. The results reveal a bioactive lipid-protein, nanometer-length scale particle that is secreted into milk not to supply energy to the infant, but to play unique, protective and regulatory roles.
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影响因子：
2.5
作者：
Mather, IH;Keenan, TW
通讯作者：
Keenan, TW
影响因子：
3
作者：
Iwamori, Masao;Takamizawa, Kotarou;Taketani, Yuji
通讯作者：
Taketani, Yuji
影响因子：
3.4
作者：
Palmer, DJ;Kelly, VC;Cooper, GJ
通讯作者：
Cooper, GJ
影响因子：
15.9
作者：
HARRIS, HW;GRUNFELD, C;RAPP, JH
通讯作者：
RAPP, JH
影响因子：
4.4
作者：
Alain K;Karrow NA;Thibault C;St-Pierre J;Lessard M;Bissonnette N
通讯作者：
Bissonnette N