The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform

Joachim Molkentin - One of the best experts on this subject based on the ideXlab platform.

  • Occurrence and biochemical characteristics of natural bioactive substances in bovine Milk Lipids.
    British Journal of Nutrition, 2000
    Co-Authors: Joachim Molkentin
    Abstract:

    Bovine Milk Lipids (BML) contain a number of bioactive substances with positive as well as negative properties, mainly in the class of fatty acids. Besides trans fatty acids (TFA), conjugated linoleic acids (CLA) are of particular interest. Apart from ruminant meat products the main source of CLA in food are BML. Although TFA as well as saturated fatty acids (12:0-16:0) are thought to be positively correlated with atherosclerosis and coronary heart disease, CLA are considered antiatherogenic. Further, CLA are reported to reduce adipose fat and to have anticarcinogenic properties. The varying CLA and TFA contents of Lipids from Milk and dairy products are positively correlated with one another. However, TFA are also negatively correlated with 12:0-16:0 in BML. Anticarcinogenic effects are also ascribed to butyric acid as well as to some phosphoLipids and ether Lipids present in BML. Moreover, the essential fatty acids 18:2n-6 and 18:3n-3 are found in BML which are involved in a variety of biochemical processes and thus have numerous functions in human metabolism. Contents of the individual bioactive components of BML are summarised taking into account also seasonal variations. The total content of bioactive substances in BML is approximately 75 % but their overall impact on human health considering benefits and drawbacks is difficult to assess.

  • Trans-18:1 acid content and profile in human Milk Lipids. Critical survey of data in connection with analytical methods
    Journal of the American Oil Chemists' Society, 1998
    Co-Authors: Robert L. Wolff, Dietz Precht, Joachim Molkentin
    Abstract:

    This study presents an in-depth, critical survey of the current knowledge about trans - 18:1 acid content and profile in human Milk Lipids. Emphasis is placed on the analytical methods employed to quantitate trans - 18:1 acids, most of which lead to imprecise quantitative data. It is demonstrated that data obtained by single gas-liquid chromatography (GLC) on polar capillary columns are underestimates by 25–40%. Several experiments indicate that the total content of trans -18:1 acids in human Milk is directly related to the quantities ingested the previous day(s), provided no gross weight loss occurs during breast-Milk feeding. Equations have been proposed to describe this relationship, and apparently the percentage of trans -18:1 isomers, relative to total fatty acids, is approximately three-fourths the quantity (in g) ingested by lactating mothers. That is, the determination of the trans -18:1 acid percentage in human Milk is a convenient means to estimate trans -18:1 acid consumption by corresponding populations. Adapted methods (i.e., silver-ion thin-layer chromatography, coupled with GLC on long polar capillary columns) allow accurate quantitation of most individual trans - 18:1 acids, more particularly of the trans -Δ16 isomer. This determination, along with a knowledge of the distribution of individual isomers in ruminant fats and partially hydrogenated oils, is a convenient means to estimate the relative contribution of these two dietary sources to the distribution of individual trans -18:1 isomers in human Milk Lipids. A comparison of human Milk and infant formulas is made with regard to trans -18:1 acid content and profile. Important differences are noted between data from European countries and from North America.

  • Trans‐18:1 acid content and profile in human Milk Lipids. Critical survey of data in connection with analytical methods
    Journal of the American Oil Chemists' Society, 1998
    Co-Authors: Robert L. Wolff, Dietz Precht, Joachim Molkentin
    Abstract:

    This study presents an in-depth, critical survey of the current knowledge about trans- 18:1 acid content and profile in human Milk Lipids. Emphasis is placed on the analytical methods employed to quantitate trans- 18:1 acids, most of which lead to imprecise quantitative data. It is demonstrated that data obtained by single gas-liquid chromatography (GLC) on polar capillary columns are underestimates by 25–40%. Several experiments indicate that the total content of trans-18:1 acids in human Milk is directly related to the quantities ingested the previous day(s), provided no gross weight loss occurs during breast-Milk feeding. Equations have been proposed to describe this relationship, and apparently the percentage of trans-18:1 isomers, relative to total fatty acids, is approximately three-fourths the quantity (in g) ingested by lactating mothers. That is, the determination of the trans-18:1 acid percentage in human Milk is a convenient means to estimate trans-18:1 acid consumption by corresponding populations. Adapted methods (i.e., silver-ion thin-layer chromatography, coupled with GLC on long polar capillary columns) allow accurate quantitation of most individual trans- 18:1 acids, more particularly of the trans-Δ16 isomer. This determination, along with a knowledge of the distribution of individual isomers in ruminant fats and partially hydrogenated oils, is a convenient means to estimate the relative contribution of these two dietary sources to the distribution of individual trans-18:1 isomers in human Milk Lipids. A comparison of human Milk and infant formulas is made with regard to trans-18:1 acid content and profile. Important differences are noted between data from European countries and from North America.

Robert H. Glew - One of the best experts on this subject based on the ideXlab platform.

  • Constancy of the fluidity of the Milk Lipids of three different human populations
    Nutrition Research, 2002
    Co-Authors: Robert H. Glew, J.a. Elliott, Yung-sheng Huang, L.-t Chuang, Dorothy J. Vanderjagt
    Abstract:

    Abstract Maintaining a proper fluid character of human Milk requires that the triglycerides be liquid. The mean melting points (MMPs) of Milk Lipids were determined using the mol percentages and melting points of the constituent fatty acids of the Lipids in Milk from three different ethnic groups in Nigeria and Nepal. The MMPs of the Milk Lipids of Fulani (n = 34) and Kanuri (n = 89) women in northern Nigeria and Nepalese women (n = 48) were 35.4°C, 35.5°C, and 35.8°C, respectively (mean, 35.6°C). We also tested the correlation between MMP and the mol% of individual fatty acids. The strongest correlations were observed with lauric acid, oleic acid, linoleic acid and arachidonic acid. The results indicate that the fluidity of the lipid fraction of Milk is maintained at 2–3°C below normal body temperature and raises interesting questions about the mechanism(s) by which the mammary gland regulates the fatty acid composition of the triglycerides it produces and secretes into Milk.

  • Fatty acid composition of the Milk Lipids of Nepalese women: correlation between fatty acid composition of serum phosphoLipids and melting point.
    Prostaglandins leukotrienes and essential fatty acids, 2001
    Co-Authors: Robert H. Glew, L.-t Chuang, Y.-s. Huang, T.a. Vander Jagt, S.k. Bhatt, M A Magnussen, Dorothy J. Vanderjagt
    Abstract:

    Abstract Milk was collected from 36 Nepalese women, 15 to 32 years of age, in order to investigate relationships between the proportions of intermediate chain-length (C10–C14) fatty acids and critical n-3 and n-6 polyunsaturated fatty acids in the Milk Lipids they were producing. Serum was also obtained from these lactating women and the fatty acid composition of their serum phospholipid fraction was determined and compared with that of the corresponding Milk lipid fraction. Compared to women in technologically advanced parts of the world, the serum phosphoLipids of the Nepalese women contained nutritionally adequate proportions of linoleic acid (LA) (16.8%), α -linolenic acid (ALA) (0.53%), arachidonic acid (AA) (5.69%), and docosahexaenoic acid (DHA) (1.42%). However, although the Milk Lipids contained adequate proportions of ALA (1.81%), AA (0.43%), and DHA (0.23%), the Lipids contained low to moderate percentages of LA (mean, 9.05%). Positive correlations were observed between the proportions of AA ( P =0.001, r =0.50) and ALA ( P =0.03, r =0.36) in the serum phosphoLipids and Milk Lipids of the women. As the proportion of C10–Cl4 fatty acids in the Milk Lipids increased from 10% to 40%, there was preferential retention of three critical n-3 and n-6 fatty acids (ALA, AA, and DHA) at the expense of two relatively abundant nonessential fatty acids, namely stearic acid and oleic acid. In addition, using fatty acid melting point data and the mol fraction of the 9 most abundant fatty acids in the Milk, we estimated the mean melting point (MMP) of the Milk Lipids of the Nepalese women. The MMPs ranged from 29.3 to 40.5°C (median, 35.5°C). These results indicate that: 1) the levels of AA and ALA in the blood of lactating mothers influence the levels of these fatty acids in the Milk they produce; 2) when the mammary gland produces a Milk that is rich in C10–Cl4 fatty acids, it somehow regulates triglyceride synthesis in such a way as to ensure that the Milk will provide the exclusively breast-fed infant with the amounts of the critical n-3 and n-6 fatty acids it requires for normal growth and development; and 3) the melting point of the Milk lipid fraction is determined mainly by the mol % of the intermediate chain-length (C10–C14) fatty acids, oleic acid, linoleic acid, and α -linolenic acid.

  • Fatty acid composition of the Milk Lipids of Fulani women and the serum phosphoLipids of their exclusively breast-fed infants
    Early human development, 2000
    Co-Authors: Dorothy J. Vanderjagt, Y.-s. Huang, Christopher D. Arndt, Seline N. Okolo, Lu-te Chuang, Robert H. Glew
    Abstract:

    Abstract We previously reported that, relative to Milk of women elsewhere in the world, the lipid fraction of Milk of Fulani women in northern Nigeria contained relatively low proportions of α-linolenic acid and docosahexaenoic acid (DHA). This led us to question the essential fatty acid status of Fulani infants and the relation between the proportion of critical n-3 and n-6 fatty acids in the serum phosphoLipids of the mothers, their Milk, and the serum phosphoLipids of their exclusively breast-fed infants. We were also interested in the effect de novo intermediate chain length-fatty acids (C10–C14) had on the proportions of critical and non-essential fatty acids in Milk. Capillary gas–liquid chromatography was used to analyze the fatty acid content of the total Milk Lipids of 34 Fulani women, as well as the fatty acid content of serum phosphoLipids of the women and their breast-fed infants during the first 6 months of life. The proportions of critical n-3 and n-6 fatty acids in the Milk of the Fulani women were adequate, but the proportions of these same fatty acids were low in their exclusively breast-fed infants. The serum phosphoLipids of the infants contained 18.8% linoleic acid, 0.13% α-linolenic acid, 12.8% arachidonic acid, and 3.40% DHA, whereas, the mean percentages of linoleic, α-linolenic, arachidonic and DHA in the serum phosphoLipids of the Fulani mothers’ were 21.4, 0.20, 9.79, and 1.97, respectively. There was a strong positive correlation between fatty acid content of serum phosphoLipids of Fulani women and the fatty acid content of their Milk Lipids. As the proportion of C10–C14 fatty acids in the Milk Lipids increased, the proportions of critical n-3 and n-6 fatty acids in Milk remained relatively constant; however, proportions of three non-essential fatty acids decreased dramatically. C10–C14 fatty acids do not appear to displace critical n-3 and n-6 fatty acids in Milk.

  • Selective retention of n-3 and n-6 fatty acids in human Milk Lipids in the face of increasing proportions of medium chain-length (C10-14) fatty acids.
    Prostaglandins leukotrienes and essential fatty acids, 1999
    Co-Authors: B.l. Schmeits, Y.-s. Huang, Dorothy J. Vanderjagt, Seline N. Okolo, Robert H. Glew
    Abstract:

    Abstract This paper reports the results of our analysis of the impact high levels of de novo fatty acids have on the proportions of essential and non-essential fatty acids in human Milk Lipids. The data for seven fatty acids (linoleic, α-linolenic, arachidonic (AA), docosahexaenoic (DHA), palmitic, stearic and oleic) were derived from several studies conducted in Nigeria. The proportion by weight of each of these fatty acids was plotted versus the proportion of C10-14 fatty acids. As the proportion of C10-14 fatty acids increased from 15 to 65%, there was not a proportional decrease in the percentages of all seven fatty acids, but, instead, preferential incorporation of the essential fatty acids, AA and DHA into the triacylglycerol component of the Milk. At the same time, the proportions of stearic and oleic acid declined by 69% and 86%, respectively. However, the proportions of linoleic acid, palmitic acid, DHA, AA and a-linolenic acid, in Milk Lipids decreased by only 44%, 40%, 39%, 28% and 2.3%, respectively. These observations indicate that as the contribution of C10-14 fatty acids increases, essential fatty acids are preferentially incorporated into Milk triacylglycerols at the expense of oleic acid and stearic acid.

  • Fatty acid composition of the Milk Lipids of women in Nepal
    Nutrition Research, 1999
    Co-Authors: B.l. Schmeits, Yung-sheng Huang, Dorothy J. Vanderjagt, S.k. Bhatt, M A Magnussen, Julia A. Cook, Emil G. Bobik, Robert H. Glew
    Abstract:

    Abstract We analyzed the fatty acid composition of the triacylglycerol and phospholipid fractions of human Milk samples obtained 2–4 weeks postpartum from 48 women living in rural Nepal. The most noteworthy aspects of the fatty acid composition of the triacylglycerol fraction were the proportions of the two essential fatty acids, linoleic acid (C18:2n-6) and α-linolenic acid (C18:3n-3). The proportion of linoleic acid was very low (7.91%), while that of α-linolenic acid was relatively high (1.93%). Together, the n-3 and n-6 polyunsaturated fatty acids accounted for 12.4% of the total fatty acids in the triacylglycerol fraction, and de novo fatty acids (C10:0–C14:0) accounted for 25.0% of the total, arachidonic acid 0.35%, and docosahexaenoic acid (DHA) 0.21% of the total. In the phospholipid fraction, the two essential fatty acids accounted for 6.38% of the fatty acid total. In the phospholipid fraction, 23.0% of the fatty acids were contributed by de novo fatty acids, 0.57% by arachidonic acid and 0.78% by DHA. The mean body mass index (BMI, kg/m 2 ) of the women in the Nepal study was in the middle range of other groups we have studied in Nigeria, yet the value of linoleic acid in the triacylglycerol fraction of their Milk was lower than the value we found in the Milk Lipids of the Nigerian women. This leads us to speculate the low proportion of linoleic acid in the Milk fat of the Nepalese women is due more to the diet of the population rather than the overall nutritional status of the mothers, as reflected in their BMI values.

James L. Mcmanaman - One of the best experts on this subject based on the ideXlab platform.

  • Human Milk Lipids: an overview
    Human Milk, 2021
    Co-Authors: James L. Mcmanaman, Jayne F. Martin Carli, Jenifer Monks
    Abstract:

    Abstract It is estimated that well-nourished women secrete over 6 kg of fat into Milk during a 6-month period of breastfeeding, which makes the lactating breast one of the most lipogenic organs in the human body. In addition to being a primary source of energy for neonates, Milk Lipids participate in the delivery of micronutrients, including fat-soluble vitamins and essential fatty acids required for infant development. The lipid content of human Milk averages 3.4% w/v, which is about the same as that of major dairy species, such as cattle and goats, but significantly less than the approximately 50% found in aquatic mammals. The precise composition of Lipids in the Milk of humans and other mammals is variable and influenced by diet, genetics, and lactation stage, among other factors. Improvements in bioanalytical methods for Lipids and proteins have led to a greater and more detailed understanding of the composition and complexity of human breast Milk Lipids and their role in neonatal nutrition and human health.

  • Electron Tomography Revels that Milk Lipids Originate from Endoplasmic Reticulum Domains with Novel Structural Features
    Journal of Mammary Gland Biology and Neoplasia, 2019
    Co-Authors: Mark S. Ladinsky, Gonzalo A. Mardones, David J. Orlicky, Kathryn E. Howell, James L. Mcmanaman
    Abstract:

    Lipid droplets (LD) are dynamically-regulated organelles that originate from the endoplasmic reticulum (ER), and function in the storage, trafficking and metabolism of neutral Lipids. In mammary epithelial cells (MEC) of lactating animals, intact LD are secreted intact into Milk to form Milk Lipids by a novel apocrine mechanism. The secretion of intact LD and the relatively large amounts of lipid secreted by lactating MEC increase demands on the cellular processes responsible for lipid synthesis and LD formation. As yet these processes are poorly defined due to limited understanding of LD-ER interactions. To overcome these limitations, we used rapid-freezing and freeze-substitution methods in conjunction with 3D electron tomography and high resolution immunolocalization to define interactions between LD with ER in MEC of pregnant and lactating rats. Using these approaches, we identified distinct ER domains that contribute to lipid droplet formation and stabilization and which possess unique features previously unrecognized or not fully appreciated. Our results show nascent lipid droplets within the ER lumen and the association of both forming and mature droplets with structurally unique regions of ER cisternae, characterized by the presence of perilipin-2, a protein implicated in lipid droplet formation, and enzymes involved in lipid synthesis. These data demonstrate that Milk Lipids originate from LD-ER domains with novel structural features and suggest a mechanism for initial droplet formation in the ER lumen and subsequent maturation of the droplets in association with ER cisternae.

  • Milk lipid secretion: recent biomolecular aspects.
    Biomolecular concepts, 2012
    Co-Authors: James L. Mcmanaman
    Abstract:

    Neonates of most species depend on Milk Lipids for calories, fat-soluble vitamins, and bioactive lipid components for growth and development during the postnatal period. To meet neonatal nutrition and development needs, the mammary gland has evolved efficient mechanisms for synthesizing and secreting large quantities of lipid during lactation. Although the biochemical steps involved in Milk lipid synthesis are understood, the identities of the genes mediating these steps and the molecular physiology of Milk lipid production and secretion have only recently begun to be understood in detail through advances in mouse genetics, gene expression analysis, protein structural properties, and the cell biology of lipid metabolism. This review discusses emerging data about the molecular, cellular, and structural determinants of Milk lipid synthesis and secretion within the context of physiological functions.

  • Determinants of adipophilin function in Milk lipid formation and secretion
    Trends in endocrinology and metabolism: TEM, 2011
    Co-Authors: Brandi M. Chong, David J. Orlicky, Philip Reigan, Kasey D. Mayle-combs, James L. Mcmanaman
    Abstract:

    In many species the lactating mammary gland is one of the most lipogenic organs of the body. The majority of the lipid produced during lactation is secreted into Milk by a novel process of membrane envelopment of cytoplasmic lipid droplets (CLDs). Adipophilin (ADRP/ADPH/PLIN2), a member of the perilipin (PAT) family of lipid droplet proteins, is hypothesized to play a pivotal role in both formation and secretion of Milk Lipids. Production of Milk Lipids is the only known example of CLD secretion, and the only process in which PAT family members undergo secretion. This review discusses emerging data on the structural and functional properties of adipophilin that determine its physiological actions and mediate its effects on Milk lipid formation and secretion.

  • Formation of Milk Lipids: a molecular perspective
    Clinical lipidology, 2009
    Co-Authors: James L. Mcmanaman
    Abstract:

    Lipids, primarily triglycerides, are major Milk constituents of most mammals, providing a large percentage of calories, essential fatty acids and bioactive Lipids required for neonatal growth and development. To meet the caloric and nutritional demands of newborns, the mammary glands of most species have evolved an enormous capacity to synthesize and secrete large quantities of Lipids during lactation. Significant information exists regarding the physiological regulation of lipid metabolism in the mammary gland from the study of dairy animals. However, detailed understanding of the molecular mechanisms regulating Milk lipid formation is only now coming into focus through advances in mouse genetics, global analysis of mammary gland gene expression, organelle protein properties and the cell biology of lipid metabolism.

Dorothy J. Vanderjagt - One of the best experts on this subject based on the ideXlab platform.

  • Constancy of the fluidity of the Milk Lipids of three different human populations
    Nutrition Research, 2002
    Co-Authors: Robert H. Glew, J.a. Elliott, Yung-sheng Huang, L.-t Chuang, Dorothy J. Vanderjagt
    Abstract:

    Abstract Maintaining a proper fluid character of human Milk requires that the triglycerides be liquid. The mean melting points (MMPs) of Milk Lipids were determined using the mol percentages and melting points of the constituent fatty acids of the Lipids in Milk from three different ethnic groups in Nigeria and Nepal. The MMPs of the Milk Lipids of Fulani (n = 34) and Kanuri (n = 89) women in northern Nigeria and Nepalese women (n = 48) were 35.4°C, 35.5°C, and 35.8°C, respectively (mean, 35.6°C). We also tested the correlation between MMP and the mol% of individual fatty acids. The strongest correlations were observed with lauric acid, oleic acid, linoleic acid and arachidonic acid. The results indicate that the fluidity of the lipid fraction of Milk is maintained at 2–3°C below normal body temperature and raises interesting questions about the mechanism(s) by which the mammary gland regulates the fatty acid composition of the triglycerides it produces and secretes into Milk.

  • Fatty acid composition of the Milk Lipids of Nepalese women: correlation between fatty acid composition of serum phosphoLipids and melting point.
    Prostaglandins leukotrienes and essential fatty acids, 2001
    Co-Authors: Robert H. Glew, L.-t Chuang, Y.-s. Huang, T.a. Vander Jagt, S.k. Bhatt, M A Magnussen, Dorothy J. Vanderjagt
    Abstract:

    Abstract Milk was collected from 36 Nepalese women, 15 to 32 years of age, in order to investigate relationships between the proportions of intermediate chain-length (C10–C14) fatty acids and critical n-3 and n-6 polyunsaturated fatty acids in the Milk Lipids they were producing. Serum was also obtained from these lactating women and the fatty acid composition of their serum phospholipid fraction was determined and compared with that of the corresponding Milk lipid fraction. Compared to women in technologically advanced parts of the world, the serum phosphoLipids of the Nepalese women contained nutritionally adequate proportions of linoleic acid (LA) (16.8%), α -linolenic acid (ALA) (0.53%), arachidonic acid (AA) (5.69%), and docosahexaenoic acid (DHA) (1.42%). However, although the Milk Lipids contained adequate proportions of ALA (1.81%), AA (0.43%), and DHA (0.23%), the Lipids contained low to moderate percentages of LA (mean, 9.05%). Positive correlations were observed between the proportions of AA ( P =0.001, r =0.50) and ALA ( P =0.03, r =0.36) in the serum phosphoLipids and Milk Lipids of the women. As the proportion of C10–Cl4 fatty acids in the Milk Lipids increased from 10% to 40%, there was preferential retention of three critical n-3 and n-6 fatty acids (ALA, AA, and DHA) at the expense of two relatively abundant nonessential fatty acids, namely stearic acid and oleic acid. In addition, using fatty acid melting point data and the mol fraction of the 9 most abundant fatty acids in the Milk, we estimated the mean melting point (MMP) of the Milk Lipids of the Nepalese women. The MMPs ranged from 29.3 to 40.5°C (median, 35.5°C). These results indicate that: 1) the levels of AA and ALA in the blood of lactating mothers influence the levels of these fatty acids in the Milk they produce; 2) when the mammary gland produces a Milk that is rich in C10–Cl4 fatty acids, it somehow regulates triglyceride synthesis in such a way as to ensure that the Milk will provide the exclusively breast-fed infant with the amounts of the critical n-3 and n-6 fatty acids it requires for normal growth and development; and 3) the melting point of the Milk lipid fraction is determined mainly by the mol % of the intermediate chain-length (C10–C14) fatty acids, oleic acid, linoleic acid, and α -linolenic acid.

  • Fatty acid composition of the Milk Lipids of Fulani women and the serum phosphoLipids of their exclusively breast-fed infants
    Early human development, 2000
    Co-Authors: Dorothy J. Vanderjagt, Y.-s. Huang, Christopher D. Arndt, Seline N. Okolo, Lu-te Chuang, Robert H. Glew
    Abstract:

    Abstract We previously reported that, relative to Milk of women elsewhere in the world, the lipid fraction of Milk of Fulani women in northern Nigeria contained relatively low proportions of α-linolenic acid and docosahexaenoic acid (DHA). This led us to question the essential fatty acid status of Fulani infants and the relation between the proportion of critical n-3 and n-6 fatty acids in the serum phosphoLipids of the mothers, their Milk, and the serum phosphoLipids of their exclusively breast-fed infants. We were also interested in the effect de novo intermediate chain length-fatty acids (C10–C14) had on the proportions of critical and non-essential fatty acids in Milk. Capillary gas–liquid chromatography was used to analyze the fatty acid content of the total Milk Lipids of 34 Fulani women, as well as the fatty acid content of serum phosphoLipids of the women and their breast-fed infants during the first 6 months of life. The proportions of critical n-3 and n-6 fatty acids in the Milk of the Fulani women were adequate, but the proportions of these same fatty acids were low in their exclusively breast-fed infants. The serum phosphoLipids of the infants contained 18.8% linoleic acid, 0.13% α-linolenic acid, 12.8% arachidonic acid, and 3.40% DHA, whereas, the mean percentages of linoleic, α-linolenic, arachidonic and DHA in the serum phosphoLipids of the Fulani mothers’ were 21.4, 0.20, 9.79, and 1.97, respectively. There was a strong positive correlation between fatty acid content of serum phosphoLipids of Fulani women and the fatty acid content of their Milk Lipids. As the proportion of C10–C14 fatty acids in the Milk Lipids increased, the proportions of critical n-3 and n-6 fatty acids in Milk remained relatively constant; however, proportions of three non-essential fatty acids decreased dramatically. C10–C14 fatty acids do not appear to displace critical n-3 and n-6 fatty acids in Milk.

  • Selective retention of n-3 and n-6 fatty acids in human Milk Lipids in the face of increasing proportions of medium chain-length (C10-14) fatty acids.
    Prostaglandins leukotrienes and essential fatty acids, 1999
    Co-Authors: B.l. Schmeits, Y.-s. Huang, Dorothy J. Vanderjagt, Seline N. Okolo, Robert H. Glew
    Abstract:

    Abstract This paper reports the results of our analysis of the impact high levels of de novo fatty acids have on the proportions of essential and non-essential fatty acids in human Milk Lipids. The data for seven fatty acids (linoleic, α-linolenic, arachidonic (AA), docosahexaenoic (DHA), palmitic, stearic and oleic) were derived from several studies conducted in Nigeria. The proportion by weight of each of these fatty acids was plotted versus the proportion of C10-14 fatty acids. As the proportion of C10-14 fatty acids increased from 15 to 65%, there was not a proportional decrease in the percentages of all seven fatty acids, but, instead, preferential incorporation of the essential fatty acids, AA and DHA into the triacylglycerol component of the Milk. At the same time, the proportions of stearic and oleic acid declined by 69% and 86%, respectively. However, the proportions of linoleic acid, palmitic acid, DHA, AA and a-linolenic acid, in Milk Lipids decreased by only 44%, 40%, 39%, 28% and 2.3%, respectively. These observations indicate that as the contribution of C10-14 fatty acids increases, essential fatty acids are preferentially incorporated into Milk triacylglycerols at the expense of oleic acid and stearic acid.

  • Fatty acid composition of the Milk Lipids of women in Nepal
    Nutrition Research, 1999
    Co-Authors: B.l. Schmeits, Yung-sheng Huang, Dorothy J. Vanderjagt, S.k. Bhatt, M A Magnussen, Julia A. Cook, Emil G. Bobik, Robert H. Glew
    Abstract:

    Abstract We analyzed the fatty acid composition of the triacylglycerol and phospholipid fractions of human Milk samples obtained 2–4 weeks postpartum from 48 women living in rural Nepal. The most noteworthy aspects of the fatty acid composition of the triacylglycerol fraction were the proportions of the two essential fatty acids, linoleic acid (C18:2n-6) and α-linolenic acid (C18:3n-3). The proportion of linoleic acid was very low (7.91%), while that of α-linolenic acid was relatively high (1.93%). Together, the n-3 and n-6 polyunsaturated fatty acids accounted for 12.4% of the total fatty acids in the triacylglycerol fraction, and de novo fatty acids (C10:0–C14:0) accounted for 25.0% of the total, arachidonic acid 0.35%, and docosahexaenoic acid (DHA) 0.21% of the total. In the phospholipid fraction, the two essential fatty acids accounted for 6.38% of the fatty acid total. In the phospholipid fraction, 23.0% of the fatty acids were contributed by de novo fatty acids, 0.57% by arachidonic acid and 0.78% by DHA. The mean body mass index (BMI, kg/m 2 ) of the women in the Nepal study was in the middle range of other groups we have studied in Nigeria, yet the value of linoleic acid in the triacylglycerol fraction of their Milk was lower than the value we found in the Milk Lipids of the Nigerian women. This leads us to speculate the low proportion of linoleic acid in the Milk fat of the Nepalese women is due more to the diet of the population rather than the overall nutritional status of the mothers, as reflected in their BMI values.

Olivia Menard - One of the best experts on this subject based on the ideXlab platform.

  • Physico-chemical behaviors of human and bovine Milk membrane extracts and their influence on gastric lipase adsorption
    Biochimie, 2020
    Co-Authors: Claire Bourlieu, Olivia Menard, Said Bouhallab, Didier Dupont, Amélie Deglaire, Wafa Mahdoueni, Gilles Paboeuf, Eric Gicquel, Stéphane Pezennec, Frederic Carriere
    Abstract:

    Milk fat globule membrane conditions the reactivity and enzymatic susceptibility of Milk Lipids. The use of bovine membrane extracts to make infant formulas more biomimetic of human Milk has been suggested recently. A comparison of the physico-chemical behavior of human and bovine Milk membrane extracts and their interaction with gastric lipase is here undertaken using biophysical tools. Milk membrane extracts (70% of polar Lipids) were obtained either pooling of mature human Milk (n = 5) or bovine butterMilk. Human extract contained more anionic glycerophosphoLipids, less phosphatidylethanolamine and more unsaturated fatty acids (57% versus 46%) than bovine extract. Human extract presented a higher compressibility, with slower increase of surface pressure, than bovine extract. Micronic liquid condensed (LC) domains were evidenced in both extracts at 10 mN/m, but the evolution differs upon compression. Upon gastric lipase addition, an adsorption preference for liquid expanded phase (LE) was observed for both extracts. However, insertion was more homogeneous in terms of height level in human extract and impacted less its lipid lateral organization than in bovine extract. Both membrane extracts share close physico-chemical properties, however human membrane higher compressibility may favour gastric lipase insertion and higher interfacial reactivity in gastric conditions.

  • the structure of infant formulas impacts their lipolysis proteolysis and disintegration during in vitro gastric digestion
    Food Chemistry, 2015
    Co-Authors: Claire Bourlieu, Alix De La Chevasnerie, Laura Sams, Olivia Menard, Florence Rousseau, Marie-noelle Madec
    Abstract:

    Abstract Milk Lipids supply most of the calories necessary for newborn growth in maternal Milk or infant formulas. The chemical composition of infant formulas has been optimized but not the structure of the emulsion. There is still a major difference between the native emulsions of Milk fat globules and processed submicronic emulsions in infant formulas. This difference may modify the kinetics of digestion of emulsions in newborns and influence lipid metabolism. To check this, semi-dynamic gastric in vitro digestions were conducted on three matrices: a standardized Milk emulsion containing native Milk fat globules referred to as minimally-processed emulsion and two processed model infant formulas (homogenized or homogenized/pasteurized). Gastric conditions mimicked those reported in newborns. The minimally-processed emulsion was lipolyzed and proteolyzed slower than processed formulas. The difference in initial structure persisted during digestion. The surface of the droplets was the key parameter to control gastric lipolysis kinetics, the pattern of released fatty acids and proteolysis by faster hydrolysis of adsorbed proteins.

  • Infant formula interface and fat source impact on neonatal digestion and gut microbiota
    European Journal of Lipid Science and Technology, 2015
    Co-Authors: Claire Bourlieu-lacanal, Olivia Menard, Karima Bouzerzour, Stéphanie Ferret-bernard, Cindy Le Bourgot, P. Le Ruyet, Sophie Chever, Amélie Deglaire, Isabelle Cuinet, Cécile Bonhomme
    Abstract:

    Human Milk is generally recognized as the gold standard in neonatal nutrition. The structure and composition of human Milk are better mimicked in infant formulas that include cow s Milk Lipids and Milk fat membrane extracts, which could also improve physiological properties. Nevertheless, very few infant formulas use cow' s Milk Lipids that are more expensive than vegetable Lipids. The potential impact of Milk lipid structure and composition on neonatal digestive hydrolysis, intestinal physiology, and gut microbiota was recently underlined by several scientific teams. In this context, the purpose of the present review was to summarize the specificity of composition and structure of human Milk and to highlight the recent results on the modulation of infant formula interfacial composition and fat source on neonatal digestive hydrolysis, intestinal physiology, and gut microbiota. More specifically, the interfacial composition of model emulsions stabilized with Milk polar Lipids will be unraveled as well as the addition of apolar Milk fat extracts in replacement to vegetable Lipids in infant formulas. The impact of partially replacing vegetable Lipids by Milk Lipids stabilized by Milk fat membranes was investigated in the piglets. This replacement in fluenced the neonatal intestinal physiology through the release of immune- modulatory Lipids, the modulation of proteolysis, and the modification of gut microbiota.Practical Applications:The potential development of infant formulas including cow’s Milk lipid fractions with a structure closer to human Milk is discussed. These more biomimetic formulas should result in enhanced nutritional bene fits concerning neonatal digestive hydrolysis, physiology, and gut microbiota development

  • Milk Lipids in infant formulas modify the proteolysis, microbiota and intestinal physiology in neonatal piglets
    2014
    Co-Authors: Isabelle Luron, Olivia Menard, Claire Bourlieu-lacanal, Karima Bouzerzour, Stéphanie Ferret-bernard, Cindy Le Bourgot, F. Morgan, P. Le Ruyet, Christian Bonhomme, Didier Dupont
    Abstract:

    Human Milk is generally recognized as the gold stallion in neonatal nutrition. Structure, composition and physiological properties of Human Milk are better mimicked in infant formulas that include Milk Lipids and Milk fat membrane extracts although very few infant formulae use Milk Lipids more expensive than vegetable Lipids. Two formulas based on i) vegetable fat (STD) or ii) a blend of vegetable fat and Milk Lipids stabilized by Milk fat membrane extracts (EXP) were distributed with an automatic Milk feeder to piglets from birth until 28 days. After euthanasia, Intestinal contents and tissues (proximal jejunum and ileum) and mesenteric lymph nodes (MLN) were collected. The residual immunoreactivity of β-lactoglobulin (β-lg) and caseins (Cns) present in the digestive compartments was determined by ELISA. The paracellular permeability (using FITC-dextran 4000) was evaluated using Ussing chambers. The EXP formula enhanced the resistance to proteolysis of β-lg and Cns. It modified microbiota with an increase in proteobacteria and a decrease in firmicutes. Ileal density (g/cm) was greater in EXP-fed piglets at 28 d. A decreased jejunal permeability was observed between d7 and d28 in EXP-fed piglets which was not observed with STD. There was an important effect of formula components on the secretory activity of MLN: a major immunosuppressor effect of the lipid fraction extracted from digestas of both formulas was evidenced. In conclusion, the lipid composition in infant formulas influenced the neonatal intestinal physiology through release of immunomodulatory Lipids, modulation of proteolysis and modification of progressive colonisation of the infant digestive tract by bacteria.

  • Addition of Milk fat in infant formula impacts neonatal gut microbiota
    2014
    Co-Authors: Isabelle Luron, Olivia Menard, Claire Bourlieu-lacanal, Karima Bouzerzour, Stéphanie Ferret-bernard, Cindy Le Bourgot, F. Morgan, P. Le Ruyet, Christian Bonhomme, Didier Dupont
    Abstract:

    Gut microflora is acknowledged as a major contributor to Health whatever the physiological stage. In the neonatal period, microbial colonization of the infant gut is essential for the development of the intestinal and immune systems. The profile of intestinal microbiota is influenced by genetics and environment, including the route of delivery and early dietary intake. The microbiota of full-term, vaginally delivered, breast-fed infant is considered as ideally healthy. Human Milk consumption shapes the infant microbiota thanks to its unique mix of antimicrobial proteins, abundant sIgA, but also Milk fat components such as polar Lipids and a broad range of fatty acids that may influence the ecology of the neonatal microbiota. Structure, composition and physiological properties of Human Milk are better mimicked in infant formulas that include Milk Lipids and Milk fat membrane extracts although very few infant formulae use Milk Lipids more expensive than vegetable Lipids. In this context, two formulas based on i) vegetable fat (STD) or ii) a blend of vegetable fat and Milk Lipids stabilized by Milk fat membrane extracts (EXP) were distributed with an automatic Milk feeder to piglets from birth until 28 days. At this stage, feces were collected and analyzed in terms of microbial diversity by metasequencing (16S rRNA extraction and sequencing, GS-FLEX 454 Roche). The EXP formula modified positively the microbiota with an increase in proteobacteria and a decrease in firmicutes. This shift is also observed in breast-fed compared to formula-fed 6 mths-old neonates.In conclusion, the Milk fat addition in infant formulas modulated the intestinal microbiota. The persistence of these modifications and their impact on adult metabolism will be further investigated to elucidate the links between early Milk fat intake, intestinal maturation and microbial colonization of the infant gut.