Quantitative proteomic analysis of milk fat globule membrane (MFGM) proteins in human and bovine colostrum and mature milk samples through iTRAQ labeling

Abstract

Milk fat globule membrane (MFGM) proteins have many functions. To explore the different proteomics of human and bovine MFGM, MFGM proteins were separated from human and bovine colostrum and mature milk, and analyzed by the iTRAQ proteomic approach. A total of 411 proteins were recognized and quantified. Among these, 232 kinds of differentially expressed proteins were identified. These differentially expressed proteins were analyzed based on multivariate analysis, gene ontology (GO) annotation and KEGG pathway. Biological processes involved were response to stimulus, localization, establishment of localization, and the immune system process. Cellular components engaged were the extracellular space, extracellular region parts, cell fractions, and vesicles. Molecular functions touched upon were protein binding, nucleotide binding, and enzyme inhibitor activity. The KEGG pathway analysis showed several pathways, including regulation of the actin cytoskeleton, focal adhesion, neurotrophin signaling pathway, leukocyte transendothelial migration, tight junction, complement and coagulation cascades, vascular endothelial growth factor signaling pathway, and adherens junction. These results enhance our understanding of different proteomes of human and bovine MFGM across different lactation phases, which could provide important information and potential directions for the infant milk powder and functional food industries.

“Omics” in Human Colostrum and Mature Milk: Looking to Old Data with New Eyes

“…In HM, fat is secreted as globules (Milk Fat Globules, MFGs) encircled by a membrane (MFGM) of lipids and proteins [ 79 , 80 , 81 , 82 ]. MFGM proteins constitute a small percentage of HM proteins, representing about 1–2% of the whole protein content, but plays several roles [ 83 , 84 ]; for example, MFGM act as transporters, emulsifiers, and stabilizers of lipids [ 79 , 81 , 85 , 86 ], and can also show anti-infective effects [ 79 , 87 , 88 ].…”

“…Moreover, some MFGM proteins take part in cell death, adhesion or locomotion, signaling pathways, response to stimuli, localization, protein or nucleotide binding, enzyme inhibition, antigen presentation, carboxylic acid or amine binding action, cell junction, complement and coagulation mechanisms, and leukocyte migration [ 79 ].…”

“…In HM and BM, a large number and a great variety of MFGM has been detected during different lactation stages, with a different expression in the two kinds of samples. In particular, the IgG H chain, Ig heavy chain variable region, neutrophil defensin 1, lactadherin, immunoglobulin lambda-like polypeptide 5, and myosin-reactive immunoglobulin heavy chain were higher in HC [ 79 ].…”

Bovine Colostrum Before or After Formula Feeding Improves Systemic Immune Protection and Gut Function in Newborn Preterm Pigs

“…Natural MM also contains various sugars (e.g., lactose, glucose, and oligosaccharides), while formula contains high levels of plantderived carbohydrates (e.g., maltodextrin), which may impair antibacterial responses (9). In addition, milk fat is replaced by vegetable oil during formula processing, and therefore, formula also lacks milk fat globule membrane, which consists of numerous lipids and proteins that have functions on immunerelated pathways (10,11).…”

Buffalo (Bubalus bubilis) colostrum and milk fat globule membrane fractions are potent antioxidants

“…Compared to MFGM very little literature is available on colostrum fat globule membranes (CFGM). The limited work carried out so far on CFGM, from human and bovine sources, has focussed on the structural and developmental proteomes [26,27,28]. In the present study the FGMs were isolated from buffalo milk and colostrum.…”