Biologically Active Polypeptides in Milk

Britton, J. Robert; Kastin, Abba J.

doi:10.1097/00000441-199102000-00007

Cited by 51 publications

(24 citation statements)

References 80 publications

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“…Other quantitative or qualitative differences in the composition of, or intake from, human milk and formula may affect sleep. Specific biologically active proteins exist in human milk, such as prolactin, growth hormone releasing factor, vasoactive intestinal peptide, deltasleep-inducing peptide, nerve growth factor, and casomorphins, which may influence sleep behavior (19). Differences in the content of long-chain polyunsaturated fatty acids may be manifested in altered brain phospholipids which may affect neural function (20).…”

Section: Discussionmentioning

confidence: 99%

Sleep Organization and Energy Expenditure of Breast-Fed and Formula-Fed Infants

et al. 1992

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ABSTRACT. Sleep organization of infants may be influenced by differences in nutrient intakes from human milk and formula. Because sleeplawake and sleep stage patterns affect energy expenditure, we hypothesized that differences in sleep organization between breast-fed and formula-fed infants might account in part for differences in energy expenditure between feeding groups. Sleep stages and cycling of 4-mo-old breast-fed (n = 10) formula-fed (n = 10) infants were studied with simultaneous measurements of energy expenditure. EEG, electrooculogram, body movement by triaxial accelerometry, heart rate, and oxygen saturation were monitored during an overnight sleep session. Sleep stages, nonrapid eye movement (NREM), and rapid eye movement (REM) were determined. Behavioral observations were recorded by video tape and by a technologist. Oxygen consumption and carbon dioxide production were measured with an indirect calorimeter. Total number and duration of sleep cycles, REM latency, number of NREM and REM epochs, and duration of NREM epochs did not differ between feeding groups. Sleep latency was shorter ( p < 0.05) and duration of REM epochs longer ( p < 0.01) in the formula-fed group. Formula-fed infants spent a higher percentage of sleep time in REM compared with the breast-fed infants (42 versus 34%) ( p < 0.003).Conversely, breast-fed infants spent a higher percentage of sleep time in NREM sleep and their heart rates during sleep were lower (114 versus 126 bpm; p < 0.01). Energy expenditure during REM sleep was 13.0 f 4.4% higher than during NREM sleep ( p < 0.001). Nonetheless, total energy expenditure during REM and NREM sleep did not differ statistically between feeding groups, even though nocturnal sleep organization was affected by infant feeding mode and contributed to the measured variability in energy expenditure observed during sleep. (Pediatr Res 32: 514-519,1992) Abbreviations NREM, nonrapid eye movement REM, rapid eye movement AA, amino acid Yo2, oxygen consumption Vcoz, carbon dioxide productionThe sleep organization of infants may be influenced by qualitative and quantitative differences in nutrient intakes from human milk and formula. The synthesis of brain neurotransmitters involved in the induction and maintenance of sleep is influenced by normal postprandial fluctuations in the availability of AA (1). Transport of tryptophan, the precursor of serotonin, across the blood-brain barrier depends on the ratio of plasma tryptophan to the sum of large neutral AA that compete for the same active transport system. Plasma AA levels in breast-fed infants have been shown to differ from those in formula-fed infants; in particular, the plasma tryptophan and tryptophan/sum of large neutral AA levels were higher in the breast-fed than in the formula-fed infants (2). Diet-induced alterations in plasma AA ratios have, in fact, been shown to affect infant sleep behavior (3).Infant state, defined as REM sleep, NREM sleep, or awake, is influenced not only by environmental factors such as nutrition, but also by mat...

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Section: Discussionmentioning

confidence: 99%

Sleep Organization and Energy Expenditure of Breast-Fed and Formula-Fed Infants

et al. 1992

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“…The organization and orientation of the diverse casein genes within their genomic cluster is highly conserved (31). Fractions of casein peptides, gained by in vivo or in vitro fermentation to simulate digestive processes, were shown to possess immunomodulatory and other functions, including by guest on May 11, 2018 http://www.jimmunol.org/ opioid-like activity and inhibition of the angiotensin-converting enzyme (1,(7)(8)(9). This is consistent with the assumption that caseins have evolved to exhibit immunomodulatory and nutritional properties, which were derived from the fact that the casein genes lie within a region of genes relevant for both tasks (31).…”

Section: Discussionmentioning

confidence: 99%

“…ince the late 1980s, milk proteins of various species have been reported to have physiological functions beyond providing a digestive substrate; in particular, immunomodulatory properties were discovered (1). Caseins are the main protein constituents of milk in most mammalian species (2).…”

mentioning

confidence: 99%

“…Caseins were believed to mainly function as an amino acid source (4) and to ameliorate the uptake of trace elements and calcium from the intestine of infants (5,6). Polypeptides in milk may be degraded by proteases within milk and the digestive tract or survive the digestive process in an intact form (1). Research has focused on fermented fragments and identified a number of immunomodulatory effects (7)(8)(9)(10)(11), such as the modulation of leukocyte adhesion (12), chemotactic properties (13)(14)(15)(16), inhibition of cell growth (17,18), modulation of the innate immune response of intestinal cells (19), amelioration of experimental inflammation (20), and chaperone-like activities (21).…”

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Casein α s1 Is Expressed by Human Monocytes and Upregulates the Production of GM-CSF via p38 MAPK

Vordenbäumen

Braukmann

Petermann

et al. 2011

The Journal of Immunology

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Caseins are major constituents of mammalian milks that are thought to be exclusively expressed in mammary glands and to function primarily as a protein source, as well as to ameliorate intestinal calcium uptake. In addition, proinflammatory and immunomodulatory properties have been reported for bovine caseins. Our aim was to investigate whether human casein α s1 (CSN1S1) is expressed outside the mammary gland and possesses immunomodulatory functions in humans as well. For this purpose, CSN1S1 mRNA was detected in primary human monocytes and CD4+ and CD8+ T cells, but not in CD19+ B cells. CSN1S1 protein was traceable in supernatants of cultured primary human CD14+ monocytes by ELISA. Similarly, CSN1S1 mRNA and protein were detected in the human monocytic cell lines HL60, U937, and THP1 but not in Mono Mac 6 cells. Moreover, permeabilized human monocytes and HL60 cells could be stained by immunofluorescence, indicating intracellular expression. Recombinant human CSN1S1 was bound to the surface of Mono Mac 6 cells and upregulated the expression of GM-CSF mRNA in primary human monocytes and Mono Mac 6 cells in a time- and concentration-dependent manner. A similar increase in GM-CSF protein was found in the culture supernatants. CSN1S1-dependent upregulation of GM-CSF was specifically blocked by the addition of the p38 MAPK inhibitor ML3403. Our results indicated that human CSN1S1 may possess an immunomodulatory role beyond its nutritional function in milk. It is expressed in human monocytes and stimulates the expression of the proinflammatory cytokine GM-CSF.

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“…Types and levels of hormones in milk have been reviewed previously (Britton and Kastin 1991;Grosvenor et al 1992;Hamosh 2001;Koldovsky 1995;Lawrence and Lawrence 1999). Human milk contains pituitary, hypothalamic, pancreatic, thyroid, parathyroid, adrenal, gonadal, and gut hormones, sometimes in concentrations exceeding maternal plasma levels (Ebrahim 1996;Grosvenor et al 1992).…”

Section: Endogenous Hormones In Human Milkmentioning

confidence: 99%

A critical review of methods for comparing estrogenic activity of endogenous and exogenous chemicals in human milk and infant formula.

Borgert¹,

LaKind²,

Witorsch³

2003

Environ Health Perspect

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In its review of hormonally active agents in the environment, the National Research Council (NRC 1999) recommended that further investigations of human exposure to natural and anthropogenic hormonally active agents be conducted to determine relative contributions of estrogen equivalents. The NRC (1999, p. 273) further recommended that the biological potency of hormonally active agents must be related to that of endogenous hormones in premenopausal and postmenopausal women and in men. Additional comparisons should be made with pharmacologic estrogens (hormonereplacement therapy and hormonal contraceptives) and phytoestrogens because large segments of the population are exposed to these compounds.In addition, the Endocrine Disruptor Screening and Testing Advisory Committee recommended that the U.S. Environmental Protection Agency (U.S. EPA) screen and potentially test "representative mixtures to which large . . . segments of the population are exposed," including human milk (EDSTAC 1998), which has raised questions regarding whether appropriate methods and data are available for performing such an assessment (LaKind and Berlin 2002).The assessment implied by the recommendations of those scientific bodies would involve using biological mechanistic information coupled with exposure data to assess overall human health risk for a particular mechanism. This concept is not new and has been used, for example, to evaluate risks to dioxin-like chemicals that are presumed or demonstrated to act through an aryl hydrocarbon (Ah) receptor-mediated mechanism (i.e., the toxic equivalents, or TEQ, approach). Similarly, Safe (1995) and NRC (1999) have compared the toxic potency of dietary and environmental estrogenic chemicals, using the concept of estrogen equivalents (EQs) where the substances are presumed to act though an estrogen receptor (ER)-mediated mechanism. On the basis of the EQ approach, Safe (1995) estimated that dietary intake of EQs from naturally occurring estrogenic compounds far exceeds dietary intake of man-made estrogenic compounds.In an extension of this approach, we initially sought to apply methods for estimating relative estrogenic potencies of endogenous and exogenous chemicals to assessing estrogenic risks for the two primary sources of infant nutrition: human milk and infant formulas. Both types of infant nutrition are complex mixtures of chemicals, and both contain an array of substances that have potential estrogenic activity. In combination with information on concentrations of endogenous and exogenous chemicals in these nutrition sources, estrogenic potency estimates would theoretically allow us to evaluate the relative magnitude of hormonal activity from naturally occurring substances compared with hormonal activity from exogenous substances. However, for reasons enumerated in this review, we believe that the current state of scientific understanding does not allow for accurate estimates by such methods. Although we recognize that hormonally active agents encompass a wide range of biochemical mecha...

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Biologically Active Polypeptides in Milk

Cited by 51 publications

References 80 publications

Sleep Organization and Energy Expenditure of Breast-Fed and Formula-Fed Infants

Sleep Organization and Energy Expenditure of Breast-Fed and Formula-Fed Infants

Casein α s1 Is Expressed by Human Monocytes and Upregulates the Production of GM-CSF via p38 MAPK

A critical review of methods for comparing estrogenic activity of endogenous and exogenous chemicals in human milk and infant formula.

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