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- Casein, Diabetes, Immunosuppression
- Casein, Hormonal Efficacy
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- Casein, Intestinal Bleeding
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- Casein, Stimulates Greater Consumption of Fat
Casein, Allergenic EfficacyA naturally occurring opioid peptide from cow's milk, beta-casomorphine-7, is a direct histamine releaser in man. Kurek M, Przybilla B, Hermann K, Ring J. Department of Dermatology, Ludwig-Maximilian-University, Munich. beta-Casomorphine-7, a naturally occurring product of cow's milk with opiate-like activity, was studied for possible direct histamine liberation activities in humans. It was found to cause concentration-dependent in vitro histamine release from peripheral leukocytes of healthy adult volunteers. Intradermal injection of beta-casomorphine-7 induced a wheal and flare reaction in the skin similar to histamine or codeine. Oral pretreatment with the H1 antagonist terfenadine significantly inhibited the skin responses to beta-casomorphine-7. The intradermal injection of an opiate receptor antagonist, naloxone, inhibited in vitro histamine release and skin reactions only in a 100-fold excess over beta-casomorphine-7. These findings suggest that beta-casomorphine-7 can be regarded as a noncytotoxic, direct histamine releaser in humans. The clinical relevance of these findings deserves further studies. Casein, Diabetes, ImmunosuppressionDiabetologia 1999 Aug;42(8):1032 Type I (insulin-dependent) diabetes mellitus and cow milk: casein variant consumption. Elliott RB, Harris DP, Hill JP, Bibby NJ, Wasmuth HE. Department of Paediatrics, School of Medicine, Auckland, New Zealand. Previously published Type I (insulin-dependent) diabetes mellitus incidence in 0 to 14-year-old children from 10 countries or areas was compared with the national annual cow milk protein consumption. Countries which were selected for study had appropriate milk protein polymorphism studies, herd breed composition information and low dairy imports from other countries. Total protein consumption did not correlate with diabetes incidence (r = +0.402), but consumption of the beta-casein A1 variant did (r = +0.726). Even more pronounced was the relation between beta-casein (A1+B) consumption and diabetes (r = +0.982). These latter two cow caseins yield a bioactive peptide beta-casomorphin-7 after in vitro digestion with intestinal enzymes whereas the common A2 variant or the corresponding human or goat caseins do not. beta-casomorphin-7 has opioid properties including immunosuppression, which could account for the specificity of the relation between the consumption of some but not all beta-casein variants and diabetes incidence. Peptides 1998;19(2):325-31 Casein, Hormonal EfficacyMilk protein-derived opioid receptor ligands. Teschemacher H, Koch G, Brantl V. Rudolf-Buchheim-Institut fur Pharmakologie, Justus-Liebig-Universitat, Giessen, Germany. (excerpt).... Thus, a number of milk protein fragments has been shown to behave like opioid receptor ligands able to address opioidergic systems in the adult's or in the neonate's organism. With respect to the proteins, which they are derived off these peptides have been named alpha-casein exorphins or casoxin D (alpha-casein), beta-casomorphins or beta-casorphin (beta-casein), casoxin or casoxin A, B, or C (k-casein), alpha-lactorphins (alpha-lactalbumin), beta-lactorphin (beta-lactoglobulin) or lactoferroxins (lactoferrin). Only casoxins and lactoferroxins display antagonistic properties; the other peptides behave like opioid receptor agonists. Most of the information available so far has been collected about beta-casomorphins. These peptides obviously can be released from beta-casein in the adult's or in the neonate's organism, where they might elicit opioid effects in the frame of a regulatory role as "food hormones". Several synthetic beta-casomorphin derivatives have been shown to be highly specific and potent mu-type opioid receptor ligands which frequently have been used as standard tools in opioid research. Int Arch Allergy Immunol 1992;97(2):115-20 Casein Peptides, Intestinal Absorption ofOpioid peptides encrypted in intact milk protein sequences. Meisel H, FitzGerald RJ. Bundesanstalt fur Milchforschung, Institut fur Chemie und Physik, Kiel, Germany. Opioid agonistic and antagonistic peptides which are inactive within the sequence of the precursor milk proteins can be released and thus activated by enzymatic proteolysis, for example during gastrointestinal digestion or during food processing. Activated opioid peptides are potential modulators of various regulatory processes in the body. Opioid peptides can interact with subepithelial opioid receptors or specific luminal binding sites in the intestinal tract. Furthermore, they may be absorbed and then reach endogenous opioid receptors. Proc Nutr Soc 2000 Aug;59(3):373-84 Casein, Intestinal BleedingA way that dairy can cause anemia, especially in infants and toddlers, is through loss of iron due to intestinal bleeding as a reaction to dairy casein. Iron deficiency anemia in infants and toddlers is associated with long-lasting diminished mental, motor, and behavioral functioning (Journal of Pediatrics 1990 116). Casein, Stimulates Greater ConsumptionAfferent signals regulating food intake. Bray GA. Pennington Biomedical Research Center, Louisiana State University, Baton Rouge 70808, USA. Food intake is a regulated system. Afferent signals provide information to the central nervous system, which is the centre for the control of satiety or food seeking. .beta-Casomorphin, a heptapeptide produced during the hydrolysis of casein, stimulates food intake in experimental animals. Diabetologia 1999 Mar;42(3):292-6 Casein, Stimulates Greater Consumption of FatBeta-casomorphins stimulate and enterostatin inhibits the intake of dietary fat in rats. Lin L, Umahara M, York DA, Bray GA. Pennington Biomedical Research Center, Louisiana State University, Baton Rouge 70808-4124, USA. The effects of beta-casomorphins 1-7, 1-5 and 1-4 on food intake of rats adapted to either a high fat (HF) or high carbohydrate (HC) diet have been studied and compared to the effects of enterostatin. Intracerebroventricular (icv) beta-casomorphin1-7 (beta-CM1-7) stimulated intake of HF diet in overnight fasted rats, but beta-CM1-5 and beta-CM1-4 were ineffective. Peripheral injection of beta-CM1-7 also increased the intake of a high fat diet, but reduced the intake of HC diet in satiated rats. Intracerebroventricular (ICV) beta-CM1-7 caused a dose-dependent increase in the intake of HF diet, but a dose-dependent inhibition of HC ingestion in satiated rats. Enterostatin (ICV) inhibited the beta-CM1-7 stimulation of HF intake, as did the general opioid antagonist naloxone. Ligand binding studies with [3H-pro] enterostatin identified on low affinity binding site (Kd 100nM) on a crude brain membrane preparation. This binding was displaced by beta-CM1-7, beta-CM1-5 and beta-CM1-4. These data suggest that at high doses enterostatin and beta-CM1-7 may interact with the same low affinity receptor to modulate intake of dietary fat. Biopolymers 1997;43(2):99-117 Download 0.98 Mb. Share with your friends:
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