Milk Fat Globule Membrane Components Research Articles

Белки мембраны молочной жировой глобулы. 8. Белок, связывающий жирные кислоты (FABP)

This article continues a series of reviews about the structure and functions of milk fat globule membrane (MFGM) proteins in cow’s milk. This installment introduces publications on the biochemistry of fatty acid binding protein (FABP), which is a polypeptide component of MFGM. The article gives a brief history of its discovery, as well as profiles the proteins that bind hydrophobic ligands and describes the methods of FABP identification in MFGM preparations. Other aspects of FABP studies include: isoforms and modern nomenclature; amino acid sequence and reactions to post-translational modification; spatial organization; mechanisms for binding fatty acids to lipids; well-investigated and hypothesized physiological functions; the effect of haplotypes on milk fatty acids, yield, and protein content.

Fractionation of milk fat globule membrane enriched materials from caprine milk cream

Comparison of typical milk fat globule membrane (MFGM) components was made first among buttermilk, butter serum, α-serum and β-serum produced from caprine milk cream, then subsequently among effects of different demulsification treatments and ripening/churning conditions applied to cream on the resulting buttermilk. Of the four initial materials, buttermilk had the highest yield of MFGM components and best retention of bioactive MFGM proteins. For the resulting buttermilk, ripening followed by churning achieved a MFGM component content comparable with that achieved with freezing followed by churning, and higher than that achieved with ripening or freezing followed by heating. To maximise MFGM component content, ripening cream at 12 °C and pH 6.7 for 12 h in an uncycled mode was indicated. Following optimised ripening, laboratory-scale and small technical-scale churning achieved a comparable content of MFGM components in buttermilk. To further increase the yield of MFGM components, one-time butter washing following cream churning was indicated.

Effects of various thermal treatments on interfacial composition and physical properties of bovine milk fat globules

This study aimed to investigate changes of milk fat globules (MFG) and their membranes after thermal treatments, and further analyzed the relationship between the stability of MFG and interfacial compositions of milk fat globule membrane (MFGM). We characterized the influence of three kinds of thermal treatments on fat globule interfacial components (including interfacial phospholipids and interfacial protein) and physical properties using phospholipidomics and several microscopy techniques. The results showed that size of MFG increased from 2.96 μm to 3.59 μm and ζ-potential decreased from −9.71 mV to −13.23 mV after thermal treatment, suggesting that MFGM was damaged and MFG occurred coalescence. Thermal treatment increased the Young’s modulus of MFGM and made membranes more fragile. The abundance of MFGM proteins decreased while casein and β-lactoglobulin increased after thermal treatment. Results of phospholipidomics showed that 27 phospholipid species could be used to distinguish the samples. Pasteurization reduced mainly SM and PC located in the outer bilayer of MFGM, while ultra-pasteurization reduced not only SM and PC but also PI and PE located in the inner leaflet. Based on correlation analysis, the increase in Young’s modulus of MFGM during thermal treatment might be related to changes in chemical components on the membrane, suggesting a potential link between the change of MFGM components and fat globule coalescence behavior.

Значение жировой глобулы женского молока для формирования липидома, физического и нервно-психического развития младенцев, находящихся на грудном вскармливании

This article presents information on human milk fat globules obtained using omics approaches. More than 420 unique lipids and 1104 types of proteins have been identified and suspended in an aqueous medium using a triple phospholipid layer membrane, the milk fat globule membrane (MFGM), which is present only in animal fat but not in vegetable oils. The structure of MFGM is dominated by proteins (xanthine oxidase, fatty acid-binding proteins, adipophilin, butyrophilin, CD36, mucin-1, lactadherin), polar lipids with high functional activities (phospholipids, gangliosides, sphingomyelin) and cholesterol. Experimental and clinical studies have established that nutrition enriched with MFGM promotes the formation of a lipidome similar to that of breastfeeding, improves brain development, cognitive, visual and neuropsychological functions. Components of MFGM may have a protective effect on the risk of cardiovascular diseases and functional digestive disorders and contribute to the programming of child health in subsequent age periods. The inclusion of MFGM-enriched ingredients in infant formulas is a new step towards their further adaptation to the composition of breast milk. Key words: infants, breastfeeding, breast milk, milk fat globule membrane

The Immunological Role of Milk Fat Globule Membrane.

Human milk is the ideal food for newborns until the age of six months. Human milk can be defined as a dynamic living tissue, containing immunological molecules, such as immunoglobulins, supra-molecular structures, such as the milk fat globule membrane (MFGM), and even entire cells, such as the milk microbiota. The milk composition changes throughout lactation to fulfill the infant's requirements and reflect the healthy/disease status of the lactating mother. Many bioactive milk components are either soluble or bound to the MFGM. In this work, we focus on the peculiar role of the MFGM components, from their structural organization in fat globules to their route into the gastrointestinal tract. Immunometabolic differences between human and bovine MFGM components are reported and the advantages of supplementing infant formula with the MFGM are highlighted.

On the use on hydroxyapatite suspensions for the separation of milk fat globule membrane components from buttermilk

The milk fat globule membrane (MFGM), which surrounds and stabilizes the fat globules, is released in buttermilk during cream churning. MFGM has many health benefits due to its composition rich in phospholipids and membrane proteins. Many techniques have been tried to separate the MFGM from the remaining milk solids non-fat, but they are challenging to carry out at an industrial scale. This research proposes a new approach to separating MFGM from buttermilk. This paper assessed the efficacy of hydroxyapatite (HA) cristal in interacting with MFGM isolates obtained from either raw or pasteurized cream. Different HA to MFGM ratios were used (10:1 and 20:1) to determine the impact of HA concentration on the adsorption. The results showed a very high affinity of the MFGM for HA and suggested the potential for its separation from buttermilk to improve its valorization.

Coffee Polyphenol, Chlorogenic Acid, Suppresses Brain Aging and Its Effects Are Enhanced by Milk Fat Globule Membrane Components.

Mice feed with coffee polyphenols (CPP, chlorogenic acid) and milk fat globule membrane (MFGM) has increased survival rates and helps retain long-term memory. In the cerebral cortex of aged mice, CPP intake decreased the expression of the proinflammatory cytokine TNF-α, and lysosomal enzyme cathepsin B. The suppression of inflammation in the brain during aging was thought to result in the suppression of the repressor element 1-silencing transcription factor (REST) and prevention of brain aging. In contrast, CPP increased the expression of REST, cAMP-responsive element binding (CREB) and transforming growth factor β1 (TGF-β1) in the young hippocampus. The increased expression of these factors may contribute to the induction of neuronal differentiation and the suppression of memory decline with aging. Taken together, these results suggest that CPP increases CREB in the young hippocampus and suppresses inflammation in the old brain, resulting in a preventive effect on brain aging. The endotoxin levels were not elevated in the serum of aged mice. Although the mechanism of action of MFGM has not yet been elucidated, the increase in survival rate with both CPP and MFGM intake suggests that adding milk to coffee may improve not only the taste, but also the function.

Infant Formula Supplemented With Milk Fat Globule Membrane, Long-Chain Polyunsaturated Fatty Acids, and Synbiotics Is Associated With Neurocognitive Function and Brain Structure of Healthy Children Aged 6 Years: The COGNIS Study.

BackgroundAdequate nutrient intake during the first few months of life plays a critical role on brain structure and function development.ObjectivesTo analyze the long-term effects of an experimental infant formula (EF) on neurocognitive function and brain structure in healthy children aged 6 years compared to those fed with a standard infant formula or breastfed.MethodsThe current study involved 108 healthy children aged 6 years and participating in the COGNIS Study. At 0–2 months, infants were randomized to receive up to 18 months of life a standard infant formula (SF) or EF enriched with milk fat globule membrane (MFGM), long-chain polyunsaturated fatty acids (LC-PUFAs) and synbiotics. Furthermore, a reference group of breastfed (BF) infants were also recruited. Children were assessed using neurocognitive tests and structural Magnetic Resonance Imaging (MRI) at 6 years old.ResultsExperimental infant formula (EF) children showed greater volumes in the left orbital cortex, higher vocabulary scores and IQ, and better performance in an attention task than BF children. EF children also presented greater volumes in parietal regions than SF kids. Additionally, greater cortical thickness in the insular, parietal, and temporal areas were found in children from the EF group than those fed with SF or BF groups. Further correlation analyses suggest that higher volumes and cortical thickness of different parietal and frontal regions are associated with better cognitive development in terms of language (verbal comprehension) and executive function (working memory). Finally, arachidonic acid (ARA), adrenic acid (AdA), docosahexaenoic acid (DHA) levels in cheek cell glycerophospholipids, ARA/DHA ratio, and protein, fatty acid, and mineral intake during the first 18 months of life seem to be associated with changes in the brain structures at 6 years old.ConclusionsSupplemented infant formula with MFGM components, LC-PUFAs, and synbiotics seems to be associated to long-term effects on neurocognitive development and brain structure in children at 6 years old.Clinical Trial Registrationhttps://www.clinicaltrials.gov/, identifier: NCT02094547.

Advancement on Milk Fat Globule Membrane: Separation, Identification, and Functional Properties.

Dairy products have become more common in people's daily diets in recent years, and numerous useful components derived from milk are widely employed in the food industry. Milk fat globule membrane (MFGM) is a kind of film that encases milk fat globules, and has been shown to have a high nutritional value. In this work, the protein, lipid, carbohydrate, and other components of MFGM are discussed, and also common separation, preparation, and analysis technologies, physicochemical properties, and functional features of MFGM are reviewed, to provide some guidance for the development and utilization of MFGM.

Milk fat globule membrane attenuates high fat diet-induced neuropathological changes in obese Ldlr-/-.Leiden mice.

Milk-fat globule membrane (MFGM) is a complex structure secreted by the mammary gland and present in mammalian milk. MFGM contains lipids and glycoproteins as well as gangliosides, which may be involved in myelination processes. Notably, myelination and thereby white matter integrity are often altered in obesity. Furthermore, MFGM interventions showed beneficial effects in obesity by affecting inflammatory processes and the microbiome. In this study, we investigated the impact of a dietary MFGM intervention on fat storage, neuroinflammatory processes and myelination in a rodent model of high fat diet (HFD)-induced obesity. 12-week-old male low density lipoprotein receptor-deficient Leiden mice were exposed to a HFD, a HFD enriched with 3% whey protein lipid concentrate (WPC) high in MFGM components, or a low fat diet. The impact of MFGM supplementation during 24-weeks of HFD-feeding was examined over time by analyzing body weight and fat storage, assessing cognitive tasks and MRI scanning, analyzing myelinization with polarized light imaging and examining neuroinflammation using immunohistochemistry. We found in this study that 24 weeks of HFD-feeding induced excessive fat storage, increased systolic blood pressure, altered white matter integrity, decreased functional connectivity, induced neuroinflammation and impaired spatial memory. Notably, supplementation with 3% WPC high in MFGM components restored HFD-induced neuroinflammation and attenuated the reduction in hippocampal-dependent spatial memory and hippocampal functional connectivity. We showed that supplementation with WPC high in MFGM components beneficially contributed to hippocampal-dependent spatial memory, functional connectivity in the hippocampus and anti-inflammatory processes in HFD-induced obesity in rodents. Current knowledge regarding exact biological mechanisms underlying these effects should be addressed in future studies.

MFGM components promote gut Bifidobacterium growth in infant and in vitro.

Infant gut microbiota which plays an important role in long-term health is mainly shaped by early life nutrition. However, the effect of nutrients on infants gut microbiota is less researched. Here, we present a study aiming to investigate in vitro a modified formula that is supplemented with milk fat globule membrane (MFGM) that were missing in common formulas when compared with human milk and to assess the impact of feeding scheme on microbiota and metabolism. A total of 44 infants including 16 from breast milk feeding, 13 from common formula feeding and 15 from modified formula feeding were analyzed, and A cross-sectional sampling of fecal and urine was done at 1month-of-age. Stool microbiota composition was characterized using high-throughput DNA sequencing, and urinary metabolome was profiled by nuclear magnetic resonance (NMR). In vitro growth experiment of Bifidobacterium with key components from MFGM was performed and analyzed by both DNA and RNA. Stool samples from the infants who were breastfed had a higher relative abundance of Bifidobacterium and a lower relative abundance of Escherichia than the formula-fed infants. The stool microbiome shifts were associated with urine metabolites changes. Three substances including lactadherin, sialic acid and phospholipid, key components of MFGM were significantly positively correlated to Bifidobacterium of stool samples from infants, and stimulated the growth rate of Bifidobacterium significantly by provided energy in vitro growth experiment with RNA analysis. These findings suggest that the key components from MFGM could improve infants' health by modulating the gut microbiome, and possibly supporting the growth of Bifidobacterium. Clinicaltrials.gov NCT02658500 (registered on January 20, 2016).

Quality of Set Yogurts Made from Raw Milk and Processed Milk Supplemented with Enriched Milk Fat Globule Membrane in a Two-Stage Homogenization Process.

Dairy products are relevant in the food industries as functional ingredients for several food products and contribute towards human nutrition in ameliorating certain disorders. In this study, set yogurts were produced from raw milk and processed milk combined with 4% Lacprodan®PL20 concentration and subjected to two-stage pressure homogenization. The total solids concentration of the mixture was raised to 15% using SMP (skim milk powder). The purpose of this study was to investigate the effect of Lacprodan®PL20 on the set yogurt quality produced by homogenization-induced pressure and its interaction with milk components. The changes in the physical and chemical attributes of the milk fat globule membrane (MFGM) via destabilization of the membrane significantly affected the physicochemical properties of set yogurts produced from processed or raw milk. There was a slight variation in MFGM-specific proteins detected in the set yogurts. Set yogurt produced from homogenized raw milk (HRM) had a considerably higher water-holding capacity, firmness, and apparent viscosity. The microstructure of HRM was dense and compacted, unlike non-homogenized raw milk (NRM) with large MFGM fragments and pore holes between the matrixes. The inclusion of homogenization showed a remarkable improvement in set yogurt quality, promoting interaction between MFGM components and milk proteins.

Milk fat globule membrane in infant nutrition: a dairy industry perspective.

This review provides an overview of the composition, structure, and biological activities of milk fat globule membrane (MFGM) compounds with focus on the future application of this compound as a food ingredient. MFGM is a particular component of mammalian milks and is comprised of a tri-layer of polar lipids, glycolipids and proteins. In recent years, MFGM has been extensively studied for the purpose of enhancing the efficacy of infant nutrition formula. For example, infant formulas supplemented with bovine MFGM have shown promising results with regard to neurodevelopment and defense against infections. Components of MFGM have been shown to present several health benefits as the proteins of the membrane have shown antiviral activity and a reduction in the incidence of diarrhea. Moreover, the presence of sphingomyelin, a phospholipid, implies beneficial effects on human health such as enhanced neuronal development in infants and the protection of neonates from bacterial infections. The development of a lipid that is similar to human milk fat would represent a significant advance for the infant formula industry and would offer high technology formulas for those infants that depend on infant formula. The complexity of the structure of MFGM and its nutritional and technological properties is critically examined in this review with a focus on issues relevant to the dairy industry.

Comparative Proteomics of Milk Fat Globule Membrane (MFGM) Proteome across Species and Lactation Stages and the Potentials of MFGM Fractions in Infant Formula Preparation.

Milk is a lipid-in-water emulsion with a primary role in the nutrition of newborns. Milk fat globules (MFGs) are a mixture of proteins and lipids with nutraceutical properties related to the milk fat globule membrane (MFGM), which protects them, thus preventing their coalescence. Human and bovine MFGM proteomes have been extensively characterized in terms of their formation, maturation, and composition. Here, we review the most recent comparative proteomic analyses of MFGM proteome, above all from humans and bovines, but also from other species. The major MFGM proteins are found in all the MFGM proteomes of the different species, although there are variations in protein expression levels and molecular functions across species and lactation stages. Given the similarities between the human and bovine MFGM and the bioactive properties of MFGM components, several attempts have been made to supplement infant formulas (IFs), mainly with polar lipid fractions of bovine MFGM and to a lesser extent with protein fractions. The aim is thus to narrow the gap between human breast milk and cow-based IFs. Despite the few attempts made to date, supplementation with MFGM proteins seems promising as MFGM lipid supplementation. A deeper understanding of MFGM proteomes should lead to better results.

Changes in bovine milk fat globule membrane protein components of cream caused by different extent of churning using a label-free proteomic approach

Churning is a common method to separate milk fat globule membrane (MFGM) from milk fat globules. In this work, we qualitatively and relative quantitatively analyzed the MFGM components obtained by churning cream for different time using a label-free proteomic approach. The result showed that 794 MFGM proteins were identified in all groups, of which 51, 14, 60 and 44 unique proteins were contained after churning cream for 2 min, 4 min, 6 min and 8 min, respectively. The sample churned for 6 min possessed the largest portion of total and unique proteins compared with other three groups. The relative abundances of proteins butyrophilin and xanthine dehydrogenase/oxidase, proteins cluster of differentiation 36 and fatty acid binding protein had the same change tendency during the continuous agitation process. Some milk serum proteins also were detected in the buttermilk. The analysis of protein profiles of MFGM at different churning time had an important guidance for enriching a certain MFGM protein.

Application of zinc and calcium acetate to precipitate milk fat globule membrane components from a dairy by-product

There has been a great deal of interest in developing isolated dairy lipid fractions that are rich in phospholipids (PL), due to their health benefits and functional properties. Dairy by-products that contain elevated levels of PL and milk fat globule membrane (MFGM) proteins can be an excellent source for these isolates. The β stream, a by-product of anhydrous milk fat production, is an excellent candidate because it contains a higher concentration of PL than many other dairy by-products. In this study, we investigated an economically feasible processing method to obtain these valuable components from the β stream. The use of zinc acetate and calcium acetate, along with mild heat treatment and pH adjustment, was effective in precipitating PL and proteins into a pellet fraction. With an additional extraction from the pellet using ethanol (90% at 70°C), a PL-enriched lipid fraction was obtained. The effective precipitation conditions were zinc acetate of 25 mM concentration at pH greater than 6.5 at 30°C, and calcium acetate of greater than 75 mM concentration at pH greater than 6.5 at 60°C. With ethanol extraction, PL recovery of 97.7 ± 1.7% from the zinc acetate precipitate and 94.9 ± 3.7% from calcium acetate precipitate were achieved.

Physiological Effects of Feeding Infants and Young Children Formula Supplemented with Milk Fat Globule Membranes.

Dietary supplementation with bovine milk fat globule membrane (MFGM) concentrates has recently emerged as a possible means to improve the health of infants and young children. Formula-fed infants are of special interest since infant formulas traditionally have lower concentrations of biologically active MFGM components than human milk. We identified 6 double-blind randomized controlled trials (DBRCT) exploring the effects of supplementing the diet of infants and children with bovine MFGM concentrates. Two studies found a positive effect on cognitive development in formula-fed infants. Three studies found a protective effect against infections at different ages during infancy and early childhood. We conclude that supplementation with MFGM during infancy and childhood appears safe, and the studies indicate positive effects on both neurodevelopment and defense against infections, especially in formula-fed infants. However, due to the small number of studies and the heterogeneity of interventions and outcomes, more high-quality DBRCTs are needed before firm conclusions can be drawn on the likely health benefits of MFGM supplementation to infants and children.

Unraveling the Complexity of Milk Fat Globules to Tailor Bioinspired Emulsions Providing Health Benefits: The Key Role Played by the Biological Membrane

Many food products are oil in water (O/W) emulsions. Milk has the specificity to be a natural O/W emulsion secreted by the lactating cells. The milk fat globules are recognized as being efficient conveyors of energy in the form of triacylglycerols and of bioactive molecules, specifically provided by the biological membrane, the MFGM, which is the interface with the gastrointestinal tract. However, the MFGM is altered in many processed dairy products and is currently absent from standard infant milk formulas. The objectives of this invited article are to evaluate whether the specific composition and structure of the MFGM and milk polar lipid assemblies, associated with their nutritional and health benefits, could be used to tailor functional emulsions bioinspired by the MFGM‐coated milk fat globules. Recent knowledge about the structure of the MFGM revealing the heterogeneous distribution of proteins and the formation of ordered lipid domains rich in milk sphingomyelin and cholesterol is presented. The impacts of the unique composition and biophysical properties of milk polar lipids on the structure and potential functions of the MFGM are highlighted. Facing the evidence of both the functional and health benefits provided by the MFGM, the preparation of MFGM‐enriched ingredients from dairy products has recently attracted wide attention. The utilization of MFGM components to tailor the surface of processed lipid droplets in food emulsions and to develop new products providing health benefits is discussed.The biological membrane surrounding milk fat globules, the milk fat globule membrane (MFGM), is of special interest for its functional and health benefits. However, the MFGM is altered in many processed dairy products and is currently absent from standard infant milk formulas, in which the processed lipid droplets are coated by milk proteins. The preparation of MFGM‐enriched ingredients from dairy products is possible at the industrial scale. The utilization of MFGM components to tailor the surface of processed lipid droplets in food emulsions will permit the development of new products providing health benefits.

Symposium review: The relevance of bovine milk phospholipids in human nutrition—Evidence of the effect on infant gut and brain development

This paper reflects the concepts reviewed during the presentation in the Joint MILK/Lactation Biology Symposium at the ADSA 2018 Annual Meeting. Our intention is to update the concepts and advances in the area of research regarding milk phospholipids or polar lipid fraction as part of a dairy ingredient used today in nutritional studies that focus on gut health as well as brain development of infants. Although processing advances have allowed the production of novel ingredients rich in milk fat globule membrane (MFGM) components, mostly monitored by phospholipid concentration and presence of membrane proteins, there is wide variability in their composition and structure. Furthermore, we aimed to include in the phospholipid fraction of milk nanovesicles designated as milk exosomes, which are secreted into milk by different secretion mechanisms than those of the fat globules but are also made up of a unique mixture of polar lipids. We consider imperative the study of polar lipid-derived structures from milk regarding composition and structure to gain insights into their biological effect in human health. Nevertheless, and tolerating the differences in composition and concentration of their components, studies supplementing the diet of infants with polar lipids (i.e., MFGM components) have shown significant advances in several areas of human health and well-being. Here we present a summary of the important components of MFGM and milk exosomes as well as an overview of the effects on gut health and brain and cognitive development when added to the diet of infants.

Disorder in Milk Proteins: Lactadherin Multifunctionality and Structure.

Milk fat globule membrane (MFGM) is one of the milk components that is produced by the lactating mammary glands and released to the milk in the form of vesicles. MFGM surrounds milk fat globule secreted by the milk producing cells and has a complex structure containing various lipids (e.g., triacylglycerides, phospholipids, and cholesterol), proteins and other macromolecules. Among the proteinaceous components of MFGM is lactadherin, also known as milk fat globule-EGF factor 8 protein (MFG-E8). Being one of the main proteins present in MFGM, lactadherin is related to milk secretion, has antimicrobial and antiviral effects, and plays important roles in the immune defense as one of the immune system molecules. Furthermore, lactadherin belongs to the family of secreted extracellular matrix proteins, and clearly can be considered as a multifunctional (or moonlighting) glycoprotein involved in regulation of many biological and physiological processes, such as angiogenesis, atherosclerosis, haemostasis, phagocytosis, and tissue remodeling. This review focuses on the similarities and differences of lactadherin among different species and describes the main functions of this protein, as well as its structure.