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Comparative Effects of Milk Containing A1 versus A2 β-Casein on Health, Growth and β-Casomorphin-7 Level in Plasma of Neonatal Dairy Calves. Animals (Basel) 2020; 11:ani11010055. [PMID: 33396812 PMCID: PMC7824610 DOI: 10.3390/ani11010055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/21/2020] [Accepted: 12/25/2020] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Bovine milk generally contains two types of the milk protein β-casein, A1 and A2. Enzymatic digestion of the A1 type yields the opioid peptide β-casomorphin-7, which is suggested to adversely affect human and animal health. This study aimed to compare the effects of milk containing either homozygote A1 or A2 β-casein on health and growth parameters in 47 dairy calves during the first three weeks of life. Additionally, we studied, for the first time, the levels of intact β-casomorphin-7 in plasma of calves fed milk of alternative β-casein genotypes. Milk feeding of “A2-milk” led to a lower milk intake and a looser fecal consistency (higher prevalence of diarrhea) compared to “A1-milk”. Nevertheless, weight gains and end weights of calves of both feeding groups were similar, which might be caused by the associated higher protein content of milk containing the A2 variant. Intact β-casomorphin-7 was detected in plasma after A1- and A2-milk consumption, but was almost 5 times higher for A1-calves. In summary, A2-milk minimized the cleavage of the opioid peptide β-casomorphin-7 and might have advantages in the development of pre-weaned dairy calves. Abstract Research has shown that digestion of A1 β-casein (β-CN) affects gastrointestinal motility and opioid activity through the release of the peptide β-casomorphin-7 (β-CM7). In the case of the A2 variant, the cleavage of β-CM7 does not occur or occurs at a very low rate. Therefore, the aim of the study was to compare the effects of milk containing either homozygote A1 or A2 β-CN on health and growth parameters of dairy calves. Forty-seven neonatal calves (24 females, 23 males) of the breeds German Holstein (GH, n = 9), German Simmental (GS, n = 33) and their crossing (GH × GS, n = 5) were used in a 21-day feeding study. Fecal score (FS), respiratory frequency (RF), and rectal body temperature (BT) were recorded daily, whereas body weight was measured at birth and at day 21 to estimate the average daily weight gain (ADG). Additionally, blood was collected from calves three times during the experimental period and, for the first time, the respective plasma samples were analyzed for intact β-CM7. Consumption of A2-milk led to a lower daily milk intake (dMI) (p < 0.05). Furthermore, fecal consistency was softer for calves fed A2-milk (p < 0.05). Although 44% of A2-calves had diarrhea or revealed a tendency towards it (FS ≥ 3), A1-calves had a prevalence of 21%. Calves with a FS of 4 were offered an electrolyte solution and received a dietary food supplement for the stabilization of the fluid and electrolyte balance. Nevertheless, similar ADG and end weights (EW) of calves fed A1- or A2-milk (p > 0.05) indicate that A2-milk may compensate higher diarrhea rates and lower dMI due to the associated higher protein content. This is the first report of intact β-CM7 in plasma of calves fed milk of either A1 or A2 β-CN. Evidence from this study suggests that due to the change in the amino-acid sequence, A2-milk might be able to prevent or, at least, to minimize the cleavage of β-CM7 in calves.
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Aslam H, Ruusunen A, Berk M, Loughman A, Rivera L, Pasco JA, Jacka FN. Unravelled facets of milk derived opioid peptides: a focus on gut physiology, fractures and obesity. Int J Food Sci Nutr 2019; 71:36-49. [PMID: 31154909 DOI: 10.1080/09637486.2019.1614540] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Beyond being a source of key nutrients, bovine milk influences physiological functions by synthesising bioactive peptides during the process of digestion. Some of the claimed negative health outcomes associated with milk consumption, such as cardiovascular diseases and type 1 diabetes may be attributed to an opioid peptide, beta-casomorphin-7 (BCM-7), derived from A1 beta-casein. BCM-7 exerts its function by binding to the μ-opioid receptors in the body. It is hypothesised that activation of the μ-opioid receptors in the gut can alter gut microbial composition, impair gut barrier integrity and bile acid metabolism, in addition to increasing gastrointestinal transit time and gut inflammation. Further, it is hypothesised that BCM-7 may influence fractures and obesity via μ-opioid receptor pathways. In conclusion, it appears that BCM-7 might have multiple functions pertinent to human health; however, the evidence is limited and warrants further pre-clinical and clinical studies for hypothesis confirmation.
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Affiliation(s)
- Hajara Aslam
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia
| | - Anu Ruusunen
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, Kuopio University Hospital, Kuopio, Finland.,Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, Orygen Youth Health Research Centre and the Centre of Youth Mental Health, The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia.,Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.,Barwon Health, Geelong, Australia
| | - Amy Loughman
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia
| | - Leni Rivera
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Metabolic Research Unit, School of Medicine, Waurn Ponds, Deakin University Victoria, Geelong, Australia
| | - Julie A Pasco
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.,Barwon Health, Geelong, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, St Albans, Australia
| | - Felice N Jacka
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Department of Psychiatry, University of Melbourne, Melbourne, Australia.,Centre for Adolescent Health, Murdoch Children's Research Institute, Melbourne, Australia.,Black Dog Institute, New South Wales, Australia
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Brooke-Taylor S, Dwyer K, Woodford K, Kost N. Systematic Review of the Gastrointestinal Effects of A1 Compared with A2 β-Casein. Adv Nutr 2017; 8:739-748. [PMID: 28916574 PMCID: PMC5593102 DOI: 10.3945/an.116.013953] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
This is the first systematic review, to our knowledge, of published studies investigating the gastrointestinal effects of A1-type bovine β-casein (A1) compared with A2-type bovine β-casein (A2). The review is relevant to nutrition practice given the increasing availability and promotion in a range of countries of dairy products free of A1 for both infant and adult nutrition. In vitro and in vivo studies (all species) were included. In vivo studies were limited to oral consumption. Inclusion criteria encompassed all English-language primary research studies, but not reviews, involving milk, fresh-milk products, β-casein, and β-casomorphins published through 12 April 2017. Studies involving cheese and fermented milk products were excluded. Only studies with a specific gastrointestinal focus were included. However, inclusion was not delimited by specific gastrointestinal outcome nor by a specific mechanism. Inclusion criteria were satisfied by 39 studies. In vivo consumption of A1 relative to A2 delays intestinal transit in rodents via an opioid-mediated mechanism. Rodent models also link consumption of A1 to the initiation of inflammatory response markers plus enhanced Toll-like receptor expression relative to both A2 and nonmilk controls. Although most rodent responses are confirmed as opioid-mediated, there is evidence that dipeptidyl peptidase 4 stimulation in the jejunum of rodents is via a nonopioid mechanism. In humans, there is evidence from a limited number of studies that A1 consumption is also associated with delayed intestinal transit (1 clinical study) and looser stool consistency (2 clinical studies). In addition, digestive discomfort is correlated with inflammatory markers in humans for A1 but not A2. Further research is required in humans to investigate the digestive function effects of A1 relative to A2 in different populations and dietary settings.
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Affiliation(s)
| | - Karen Dwyer
- School of Medicine, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Keith Woodford
- Agri-Food Systems, Lincoln University, Lincoln, New Zealand; and
| | - Natalya Kost
- Research Center of Mental Health, Russian Academy of Medical Sciences, Moscow, Russia
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Trivedi MS, Hodgson NW, Walker SJ, Trooskens G, Nair V, Deth RC. Epigenetic effects of casein-derived opioid peptides in SH-SY5Y human neuroblastoma cells. Nutr Metab (Lond) 2015; 12:54. [PMID: 26664459 PMCID: PMC4673759 DOI: 10.1186/s12986-015-0050-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 12/03/2015] [Indexed: 12/18/2022] Open
Abstract
Background Casein-free, gluten-free diets have been reported to mitigate some of the inflammatory gastrointestinal and behavioral traits associated with autism, but the mechanism for this palliative effect has not been elucidated. We recently showed that the opioid peptide beta-casomorphin-7, derived from bovine (bBCM7) milk, decreases cysteine uptake, lowers levels of the antioxidant glutathione (GSH) and decreases the methyl donor S-adenosylmethionine (SAM) in both Caco-2 human GI epithelial cells and SH-SY5Y human neuroblastoma cells. While human breast milk can also release a similar peptide (hBCM-7), the bBCM7 and hBCM-7 vary greatly in potency; as the bBCM-7 is highly potent and similar to morphine in it's effects. Since SAM is required for DNA methylation, we wanted to further investigate the epigenetic effects of these food-derived opioid peptides. In the current study the main objective was to characterize functional pathways and key genes responding to DNA methylation effects of food-derived opioid peptides. Methods SH-SY5Y neuroblastoma cells were treated with 1 μM hBCM7 and bBCM7 and RNA and DNA were isolated after 4 h with or without treatment. Transcriptional changes were assessed using a microarray approach and CpG methylation status was analyzed at 450,000 CpG sites. Functional implications from both endpoints were evaluated via Ingenuity Pathway Analysis 4.0 and KEGG pathway analysis was performed to identify biological interactions between transcripts that were significantly altered at DNA methylation or transcriptional levels (p < 0.05, FDR <0.1). Results Here we show that hBCM7 and bBCM7, as well as morphine, cause epigenetic changes affecting gene pathways related to gastrointestinal disease and inflammation. These epigenetic consequences exhibited the same potency order as opiate inhibition of cysteine uptake insofar as hBCM7 was less potent than bBCM7, which was less potent than morphine. Conclusion Our findings indicate that epigenetic effects of milk-derived opiate peptides may contribute to GI dysfunction and inflammation in sensitive individuals. While the current study was performed using SH-SY5Y neuronal cellular models, similar actions on other cells types might combine to cause symptoms of intolerance. These actions may provide a potential contributing mechanism for the beneficial effects of a casein-free diet in alleviating gastrointestinal symptoms in neurological conditions including autism and other conditions. Lastly, our study also contributes to the evolving awareness of a “gut-brain connection”. Electronic supplementary material The online version of this article (doi:10.1186/s12986-015-0050-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Malav S Trivedi
- Department of Pharmaceutical Sciences, Nova Southeastern University, Rm # 3103, HPD building, Fort Lauderdale, FL USA
| | - Nathaniel W Hodgson
- Department of Molecular and Cellular Biology, Harvard Medical School, Boston, MA USA
| | - Stephen J Walker
- Wake Forest Institute for Regenerative Medicine, Wake Forest University Health Sciences, Winston Salem, NC USA
| | - Geert Trooskens
- Department of Mathematical Modelling, Statistics and Bioinformatics, University of Ghent, Ghent, Belgium
| | - Vineeth Nair
- Department of Pharmaceutical Sciences, Nova Southeastern University, Rm # 3103, HPD building, Fort Lauderdale, FL USA
| | - Richard C Deth
- Department of Pharmaceutical Sciences, Nova Southeastern University, Rm # 3103, HPD building, Fort Lauderdale, FL USA
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Wada Y, Lönnerdal B. Bioactive peptides released by in vitro digestion of standard and hydrolyzed infant formulas. Peptides 2015; 73:101-5. [PMID: 26385395 DOI: 10.1016/j.peptides.2015.09.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/05/2015] [Accepted: 09/12/2015] [Indexed: 01/21/2023]
Abstract
Hydrolyzed infant formulas serve as appropriate nutritional sources for infants afflicted with cow's milk allergy, and milk proteins in hydrolyzed formulas are industrially hydrolyzed extensively or partially. To investigate whether industrial hydrolysis may modulate the digestive trajectory of milk proteins, thereby releasing different profiles of bioactive peptides compared with standard formulas, both standard and hydrolyzed formulas were subjected to in vitro digestion and formation of bioactive peptides were compared. One standard, one extensively hydrolyzed, and one partially hydrolyzed infant formula were digested in vitro with pepsin and pancreatin, taking into account the higher gastric pH of infants, and the digesta were subjected to peptidomic analysis. The standard formula released a larger variety of bioactive peptides than from the hydrolyzed formulas, indicating that industrial hydrolysis of milk proteins may generally attenuate their indigenous bioactivities such as antibacterial, immuno-regulatory, and anti-oxidative activities. Conversely, industrial hydrolysis may facilitate the formation of bioactive peptides from hydrophobic proteins/regions such as β-LG and the "strategic zone" of β-CN, which encrypt bioactive peptides including a dipeptidyl dipeptidase-4-inhibitory, hypocholesterolemic, and opioid peptides. Infants fed hydrolyzed infant formulas may be influenced by milk protein-derived bioactive peptides in a manner different from those fed standard formula.
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Affiliation(s)
- Yasuaki Wada
- Department of Nutrition, University of California, Davis, One Shields Ave., Davis, CA 95616, USA; Nutritional Science Institute, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama, Kanagawa Pref. 252-8583, Japan
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, One Shields Ave., Davis, CA 95616, USA.
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Wada Y, Lönnerdal B. Bioactive peptides derived from human milk proteins — mechanisms of action. J Nutr Biochem 2014; 25:503-14. [DOI: 10.1016/j.jnutbio.2013.10.012] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 10/03/2013] [Accepted: 10/23/2013] [Indexed: 01/14/2023]
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ul Haq MR, Kapila R, Shandilya UK, Kapila S. Impact of Milk Derived β-Casomorphins on Physiological Functions and Trends in Research: A Review. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2014. [DOI: 10.1080/10942912.2012.712077] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Osborne S, Chen W, Addepalli R, Colgrave M, Singh T, Tran C, Day L. In vitrotransport and satiety of a beta-lactoglobulin dipeptide and beta-casomorphin-7 and its metabolites. Food Funct 2014; 5:2706-18. [DOI: 10.1039/c4fo00164h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In vitrotransport of β-CM7 occurs through rapid hydrolysis into three peptide metabolites that transport at variable rates.
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Affiliation(s)
- Simone Osborne
- CSIRO Animal, Food and Health Sciences
- St Lucia, Australia
| | - Wei Chen
- CSIRO Animal, Food and Health Sciences
- St Lucia, Australia
| | - Rama Addepalli
- CSIRO Animal, Food and Health Sciences
- St Lucia, Australia
| | | | - Tanoj Singh
- CSIRO Animal, Food and Health Sciences
- Werribee, Australia
| | - Cuong Tran
- CSIRO Animal, Food and Health Sciences
- Adelaide, Australia
| | - Li Day
- CSIRO Animal, Food and Health Sciences
- Werribee, Australia
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Abstract
In addition to supplying essential nutrients, some food proteins can confer additional health benefits beyond nutrition. The presence of bioactive proteins and peptides in different foods is a factor not currently taken into consideration when assessing the dietary quality of food proteins. The range of described physiological benefits attributed to bioactive proteins and peptides is diverse. Multiple factors can potentially impact on the ability of a bioactive peptide or protein to elicit an effect. Although some food proteins act directly in their intact form to elicit their effects, generally it is peptides derived from digestion, hydrolysis or fermentation that are of most interest. The levels of bioactive peptides generated must be sufficient to elicit a response, but should not be so high as to be unsafe, thus causing negative effects. In addition, some peptides cause systemic effects and therefore must be absorbed, again in sufficient amounts to elicit their action. Many studies to date have been carried out in vitro; therefore it is important that further trials are conducted in vivo to assess efficacy, dose response and safety of the peptides, particularly if health related claims are to be made. Therefore, methods must be developed and standardised that enable the measurement of health benefits and also the level of bioactive peptides which are absorbed into the bloodstream. Once standardised, such methods may provide a new perspective and an additional mechanism for analysing protein quality which is currently not encompassed by the use of the protein digestibility-corrected amino acid score (PDCAAS).
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10
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A mini-review on health and nutritional aspects of cheese with a focus on bioactive peptides. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s13594-012-0066-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Wasilewska J, Sienkiewicz-Szłapka E, Kuźbida E, Jarmołowska B, Kaczmarski M, Kostyra E. The exogenous opioid peptides and DPPIV serum activity in infants with apnoea expressed as apparent life threatening events (ALTE). Neuropeptides 2011; 45:189-95. [PMID: 21334743 DOI: 10.1016/j.npep.2011.01.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 12/22/2010] [Accepted: 01/22/2011] [Indexed: 11/29/2022]
Abstract
Casein-derived peptides have been suggested to play a role in sudden infant death syndrome (SIDS). In this study, we have determined the content of bovine β-casomorphin-7 (bBCM-7) and the activity of dipeptidyl peptidase-IV (DPPIV) in sera of infants with apparent life threatening events (ALTE syndromes, 'near miss SIDS'). We have found that the sera of some infants after an apnoea event contained more β-casomorphin-7 than that of the healthy infants in the same age. In all the children after an apnoea event, however, a lowered DPPIV was detected. We suspect that the low activity of that peptidase may be responsible for opioid-induced respiratory depression, induced by bBCM-7 in the general circulation.
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Affiliation(s)
- Jolanta Wasilewska
- Department of Paediatrics, Gastroenterology and Allergic Diseases, The Medical University of Białystok, Poland
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Wang Z, Wang W, Wang W, Xu L, Chen G, Fu F. Separation and determination of β-casomorphins by using glass microfluidic chip electrophoresis together with laser-induced fluorescence detection. J Sep Sci 2010; 34:196-201. [DOI: 10.1002/jssc.201000634] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/19/2010] [Accepted: 11/02/2010] [Indexed: 11/07/2022]
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Kost NV, Sokolov OY, Kurasova OB, Dmitriev AD, Tarakanova JN, Gabaeva MV, Zolotarev YA, Dadayan AK, Grachev SA, Korneeva EV, Mikheeva IG, Zozulya AA. Beta-casomorphins-7 in infants on different type of feeding and different levels of psychomotor development. Peptides 2009; 30:1854-60. [PMID: 19576256 DOI: 10.1016/j.peptides.2009.06.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/19/2009] [Accepted: 06/24/2009] [Indexed: 10/20/2022]
Abstract
Casomorphins are the most important during the first year of life, when postnatal formation is most active and milk is the main source of both nutritive and biologically active material for infants. This study was conducted on a total of 90 infants, of which 37 were fed with breast milk and 53 were fed with formula containing cow milk. The study has firstly indicated substances with immunoreactivity of human (irHCM) and bovine (irBCM) beta-casomorphins-7 in blood plasma of naturally and artificially fed infants, respectively. irHCM and irBCM were detected both in the morning before feeding (basal level), and 3h after feeding. Elevation of irHCM and irBCM levels after feeding was detected mainly in infants in the first 3 months of life. Chromatographic characterization of the material with irBCM has demonstrated that it has the same molecular mass and polarity as synthetic bovine beta-casomorphin-7. The highest basal irHCM was observed in breast-fed infants with normal psychomotor development and muscle tone. In contrast, elevated basal irBCM was found in formula-fed infants showing delay in psychomotor development and heightened muscle tone. Among formula-fed infants with normal development, the rate of this parameter directly correlated to basal irBCM. The data indicate that breast feeding has an advantage over artificial feeding for infants' development during the first year of life and support the hypothesis for deterioration of bovine casomorphin elimination as a risk factor for delay in psychomotor development and other diseases such as autism.
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Affiliation(s)
- Natalya V Kost
- National Research Center for Mental Health RAMS, 113152 Moscow, Zagorodnoe shosse 2/2, Russia.
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Leite AM, Castral TC, Scochi CGS. Pode a amamentação promover alívio da dor aguda em recém-nascidos? Rev Bras Enferm 2006; 59:538-42. [PMID: 17340731 DOI: 10.1590/s0034-71672006000400012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Trata-se de um estudo de revisão cujo objetivo foi identificar a eficácia da amamentação e dos aspectos que a congregam (contato, sucção, odor e leite) como medidas não- farmacológicas no alívio da dor aguda em recém-nascidos. Os 14 artigos analisados foram obtidos pelo Medline/PubMed. Verificou-se diferenças metodológicas quanto à amostragem, procedimentos dolorosos, períodos e maneira de administrar o tratamento e variáveis mensuradas. Percebeu-se a eficácia da amamentação e dos aspectos que a congregam, no alívio da dor aguda. Percebe-se a necessidade de estudos que avaliem o seu efeito analgésico antes do procedimento doloroso, até a recuperação, tempo este, suficiente para atingir-se o efeito analgésico pós-absortivo do leite. Deve-se considerar a interação entre todos os componentes que estão contidos na amamentação.
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Affiliation(s)
- Adriana Moraes Leite
- Departamento de Enfermagem Materno-Infantil e Saúde Pública da Escola de Enfermagem de Ribeirão Preto da Universidade de São Paulo
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Guesdon B, Messaoudi M, Lefranc-Millot C, Fromentin G, Tomé D, Even PC. A tryptic hydrolysate from bovine milk alphaS1-casein improves sleep in rats subjected to chronic mild stress. Peptides 2006; 27:1476-82. [PMID: 16303212 DOI: 10.1016/j.peptides.2005.10.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Revised: 10/02/2005] [Accepted: 10/04/2005] [Indexed: 11/26/2022]
Abstract
The putative effects of a tryptic bovine alphaS1-casein hydrolysate on stress-induced sleep disorders were investigated and their possible link with typical blood stress parameters such as plasma corticosterone concentrations and glycaemia was assessed. Rats were subjected to chronic stress in the form of environmental disturbances, while receiving an oral administration of the alphaS1-casein hydrolysate (CH). Chronic stress significantly reduced sleep duration in control rats during the first 2 days of the stress period, but stress-induced sleep disturbance was prevented in CH-treated rats. Indeed, CH administration allowed the maintenance of slow wave sleep (SWS) duration and even a slight increase in paradoxical sleep (PS) duration in treated rats. Results on plasma corticosterone concentrations and on glycemia values were inconclusive with respect to the implication of the HPA axis in this study. However, the protective effect of the alphaS1-casein hydrolysate on sleep during exposure to our chronic mild stress conditions may be mediated by modulation of the central adrenergic response.
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Affiliation(s)
- Benjamin Guesdon
- UMR INRA 914 Physiologie de la Nutrition et du Comportement Alimentaire, Institut National Agronomique Paris-Grignon, 16 rue Claude Bernard, 75231 Paris Cedex 05, France.
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Birgisdottir BE, Hill JP, Thorsson AV, Thorsdottir I. Lower consumption of cow milk protein A1 beta-casein at 2 years of age, rather than consumption among 11- to 14-year-old adolescents, may explain the lower incidence of type 1 diabetes in Iceland than in Scandinavia. ANNALS OF NUTRITION AND METABOLISM 2006; 50:177-83. [PMID: 16407643 DOI: 10.1159/000090738] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 09/12/2005] [Indexed: 11/19/2022]
Abstract
AIM To compare the consumption of the cow milk proteins A1 and B beta-casein among children and adolescents in Iceland and Scandinavia (Norway, Denmark, Sweden and Finland) as this might explain the lower incidence of type 1 diabetes (per 100,000/year, 0-14 years) in Iceland. METHODS The consumption of A1 beta-casein in each country among 2- and 11- to 14-year-old children was calculated from results on food intake and on cow milk protein concentration. The consumption values were then compared and evaluated against the incidence of type 1 diabetes. RESULTS There was a significant difference between the consumption of A1 (p = 0.034) as well as the sum of A1 and B (p = 0.021) beta-casein in Iceland and Scandinavia for 2-year-old children. In the same age group, consumption of A1 beta-casein correlated with the incidence of type 1 diabetes in the countries (r = 0.9; p = 0.037). No significant difference in consumption of A1 or the sum of A1 and B beta-casein was found for 11- to 14-year-old adolescents. CONCLUSION This study supports that lower consumption of A1 beta-casein might be related to the lower incidence of type 1 diabetes in Iceland than in Scandinavia. Additionally it indicates that consumption in young childhood might be of more importance for the development of the disease incidence than consumption in adolescence.
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Affiliation(s)
- B E Birgisdottir
- Unit for Nutrition Research, Landspitali University Hospital & Department of Food Science, Reykjavik, Iceland
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18
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Bell SJ, Grochoski GT, Clarke AJ. Health Implications of Milk Containing β-Casein with the A2Genetic Variant. Crit Rev Food Sci Nutr 2006; 46:93-100. [PMID: 16403684 DOI: 10.1080/10408390591001144] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Milk from dairy cows has long provided a high quality source of protein and selected micronutrients such as calcium to most populations. Recently, a relationship between disease risk and consumption of a specific bovine ss-casein fraction either A1 or A2 genetic variants has been identified. Populations, which consume milk containing high levels of ss-casein A2 variant, have a lower incidence of cardiovascular disease and type 1 diabetes. Furthermore, consumption of milk with the A2 variant may be associated with less severe symptoms of autism and schizophrenia. The mechanism of action focuses on ss-casein A1 and related forms preferentially that are able to produce a bioactive opioid peptide, ss-casomorphin-7 (ss-CM-7) during digestion. Infants may absorb ss-CM-7 due to an immature gastrointestinal tract. Adults, on the other hand, appear to reap the biological activity locally on the intestinal brush boarder. ss-CM-7 can potentially affect numerous opioid receptors in the nervous, endocrine, and immune systems. Whether there is a definite health benefit to milk containing the A2 genetic variant is unknown and requires further investigation.
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Affiliation(s)
- Stacey J Bell
- Research and Development, Ideasphere, Inc., 56 Amherst Road, Belmont, MA, 02478, USA.
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Allison AJ, Clarke AJ. Further research for consideration in ‘the A2 milk case’. Eur J Clin Nutr 2005; 60:921-4; reply 924-5. [PMID: 16189549 DOI: 10.1038/sj.ejcn.1602276] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Mihatsch WA, Franz AR, Kuhnt B, Högel J, Pohlandt F. Hydrolysis of casein accelerates gastrointestinal transit via reduction of opioid receptor agonists released from casein in rats. Neonatology 2004; 87:160-3. [PMID: 15572871 DOI: 10.1159/000082367] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2004] [Accepted: 09/20/2004] [Indexed: 11/19/2022]
Abstract
BACKGROUND Protein hydrolysate accelerates gastrointestinal transit (GIT) and feeding advancement in preterm infants compared to native protein. In rat pups, opioid receptor agonists released from casein during digestion such as beta-casomorphins slow down GIT. We hypothesized that hydrolysis of casein reduces the opioid activity released during digestion thereby accelerating GIT compared to native casein. OBJECTIVE The aim of the present study was to investigate whether casein hydrolysate accelerates GIT compared to native casein and whether pretreatment with naloxone, an opioid receptor blocker, abolishes this difference in rat pups. METHODS In a randomized controlled trial following a 2 x 2 factorial design, 216 female Wistar rat pups were fed with pellets based on hydrolyzed or native casein. After pretreatment with naloxone or normal saline, carmine red was administered by oro-gastric gavage as a tracer for GIT velocity measurement. Four hours later the animals were sacrificed, their intestine was removed and the length of the colon from the cecocolonic junction to the anus was measured. GIT was recorded as percentage of the total colonic length (percentage of colonic transit) passed by carmine red. Data were given as mean +/- SD. RESULTS GIT was significantly higher with hydrolyzed casein compared to native casein formula (77.4 +/- 17 and 51.2 +/- 20%), but there was no difference after naloxone pretreatment (77.1 +/- 16 and 76.5 +/- 17%). DISCUSSION The present data suggest that hydrolysis of casein accelerates GIT via reduction of opioid activity released during digestion. Further studies are required to investigate to which extent these rat pub data apply to preterm infants.
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Affiliation(s)
- W A Mihatsch
- Department of Pediatrics, Ulm University, Ulm, Germany.
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Abstract
Sudden infant death syndrome (SIDS) is the most common cause of death in infants and its pathogenesis is complex and multifactorial. The aim of this review is to summarize recent novel findings regarding the possible association of beta-casomorphin (beta-CM) to apnea in SIDS, which has not been widely appreciated by pediatricians and scientists. beta-CM is an exogenous bioactive peptide derived from casein, a major protein in milk and milk products, which has opioid activity. Mechanistically, circulation of this peptide into the infant's immature central nervous system might inhibit the respiratory center in the brainstem leading to apnea and death. This paper will review the possible relationship between beta-CM and SIDS in the context of passage of beta-CM through the gastrointestinal tract and the blood-brain barrier (BBB), permeability of the BBB to peptides in infants, and characterization of the casomorphin system in the brain.
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Affiliation(s)
- Zhongjie Sun
- Department of Medicine, College of Medicine, University of Florida, Box 100274, 1600 SW Archer Road, Gainesville, FL 32610, USA.
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Pihlanto A, Korhonen H. Bioactive peptides and proteins. ADVANCES IN FOOD AND NUTRITION RESEARCH 2003; 47:175-276. [PMID: 14639784 DOI: 10.1016/s1043-4526(03)47004-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- Anne Pihlanto
- MTT Agrifood Research Finland, Food Research, 31600 Jokioinen, Finland
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Abstract
Autism is a collection of behavioral symptoms characterized by dysfunction in social interaction and communication in affected children. It is typically associated with restrictive, repetitive, and stereotypic behavior and manifests within the first 3 years of life. The cause of this disorder is not known. Over the past decade, a significant upswing in research has occurred to examine the biologic basis of autism. Recent clinical studies have revealed a high prevalence of gastrointestinal symptoms, inflammation, and dysfunction in children with autism. Mild to moderate degrees of inflammation were found in both the upper and lower intestinal tract. In addition, decreased sulfation capacity of the liver, pathologic intestinal permeability, increased secretory response to intravenous secretin injection, and decreased digestive enzyme activities were reported in many children with autism. Treatment of digestive problems appears to have positive effects on autistic behavior. These new observations represent only a piece of the unsolved autism "puzzle" and should stimulate more research into the brain-gut connection.
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Affiliation(s)
- Karoly Horvath
- Department of Pediatrics, University of Maryland School of Medicine, 22 South Greene Street, N5W70, Box 140, Baltimore, MD 21201-1595, USA. E-mail:
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Patten GS, Head RJ, Abeywardena MY, McMurchie EJ. An apparatus to assay opioid activity in the infused lumen of the intact isolated guinea pig ileum. J Pharmacol Toxicol Methods 2001; 45:39-46. [PMID: 11489663 DOI: 10.1016/s1056-8719(01)00116-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A modified apparatus is described that provides for the simultaneous bathing of the serosa of an intact piece of isolated guinea pig ileum while allowing infusion of the isolated lumen. The comparative compartmental potency of the opioid agonists morphine, casomorphins, and enkephalins to inhibit electrically driven contractions are described in this system. The rank-order potency for serosally applied opioid agonists was (IC(50) values, nM): [D-Ala(2),N-Me-Phe(4),Gly-ol(5)]-enkephalin (DAMGO) (15)>[D-Ala(2),D-Leu(5)]-enkephalin (DADLE) (35)> or =morphine (46)> or =[D-Ala(2)]-met-enkephalinamide (55)>[D-Ala(2)]-beta-casomorphin[1--4] amide (122)>beta-casomorphin[1--4] amide (940)>met- and leu-enkephalin (>6000). This contrasted to the rank-order potency for the luminally applied opioid agonists: DADLE (63)>DAMGO (135)>[D-Ala(2)]-met-enkephalinamide=morphine (4700)>[D-Ala(2)]-beta-casomorphin[1--4] amide (29000). beta-Casomorphin[1--4] amide, leu-enkephalin and met-enkephalin are mostly inactive when applied luminally. Furthermore, the opioid antagonists, casoxin 4 and [D-Ala(2)]-casoxin 4, when infused into the lumen, significantly overcame the inhibitory effect of morphine added to the serosal side. This model provides an assay and screening system to differentiate between the effects of chemical agents applied via the blood stream (serosa) or food side (lumen) on quiescent or electrically driven gut activity of the nervous plexi or receptor systems of the ileum.
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Affiliation(s)
- G S Patten
- CSIRO Health Sciences and Nutrition, Kintore Avenue, P.O. Box 10041 Adelaide BC, 5000, Australia.
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Abstract
Milk is mammalian characteristic and is of particular importance for humans: Mother's milk or its substitutes from cows' milk are absolutely essential nutriments for the neonate and cows' milk also represents a basic foodstuff for adults. However, in addition to their well-known nutritive role, milk constituents apparently are also able to carry specific information from the milk producer's to the milk receiver's organism: 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.
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Affiliation(s)
- H Teschemacher
- Rudolf-Buchheim-Institut für Pharmakologie, Justus-Liebig-Universität, Giessen, Germany
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Sakaguchi M, Murayama K, Yabe K, Satoh M, Takeuchi M, Matsumura E. Beta-casomorphin-5 stimulates neurite outgrowth in a mouse neuroblastoma cell line (Neuro-2a). Neurosci Lett 1998; 251:97-100. [PMID: 9718983 DOI: 10.1016/s0304-3940(98)00500-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We studied the effect of beta-casomorphin-5 (mu-acting opioid peptides derived from milk protein beta-casein) on neurite outgrowth of mouse neuroblastoma cell line, Neuro-2a. Beta-casomorphin-5 stimulated neurite outgrowth of Neuro-2a cells in a naloxone-reversible manner. The stimulating effect of beta-casomorphin-5 was observed even at picomolar concentrations. The selective mu-agonist, (D-Ala2, N-Me-Phe4, Gly5-ol)-enkephalin (DAMGO) exhibited the similar stimulating effect only at micromolar concentrations. On the other hand, (D-Pen(2,5))-enkephalin (DPDPE) (a delta-agonist), U-50,488 (a kappa-agonist), and endogenous opioid peptides, such as enkephalins and dynorphin A (1-13), showed no such stimulating effect. These results suggest that the neurite outgrowth-stimulating action of beta-casomorphin-5 may be mediated via a receptor which has mu-like characteristics and high sensitivity to beta-casomorphin-5, and that beta-casomorphins may play a role as a neurite elongation factor during the suckling period.
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Affiliation(s)
- M Sakaguchi
- Laboratory of Cell Biology, Osaka University of Pharmaceutical Sciences, Takatsuki, Japan
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Xu R. Bioactive peptides in milk and their biological and health implications. FOOD REVIEWS INTERNATIONAL 1998. [DOI: 10.1080/87559129809541147] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
Two experiments determined behavioral effectiveness of beta-casomorphins (beta-CM) in 10-d-old rats by evaluating changes in heat escape latency from a 48 degrees C stimulus applied to a forepaw. In one study rats were injected systemically with beta-CM4, -5, or -7 at a dose range of 0.1-2.5 mg/kg. Only beta-CM5 was effective, and the dose-response relationship was graded. The second study evaluated the locus of action of beta-CM5 through two experimental manipulations: first, by injecting it (0.25 microgram) into the lateral ventricles and by attempting to block its effects with systemic injections of naloxone. Second, rats received intracerebroventricular injections of naloxone (0.25 microgram) and systemic injections of beta-CM. beta-CM was effective centrally, suggesting central detection of the drug. Naloxone injected into the lateral ventricles blocked the effects of systemic administration of beta-CM, implying that circulating beta-CM or their precursors cause behavioral change through central mechanisms.
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Affiliation(s)
- E M Blass
- Department of Psychology, Cornell University, Ithaca, New York 14853
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Schlimme E, Meisel H. Bioactive peptides derived from milk proteins. Structural, physiological and analytical aspects. DIE NAHRUNG 1995; 39:1-20. [PMID: 7898574 DOI: 10.1002/food.19950390102] [Citation(s) in RCA: 158] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The primary function of dietary proteins is to supply the body adequately with indispensable amino acids and organic nitrogen. Little attention has been paid up to date to milk proteins, in particular caseins, that are currently the main source of biologically active peptides, although other animal as well as vegetable proteins are known to contain potentially bioactive sequences. Such regulatory peptides can be released by enzymatic proteolysis of caseins in vitro and in vivo and may act as potential physiological modulators of metabolism during the intestinal digestion of the diet. It has been proved that bioactive peptides derived from caseins, such as beta-casomorphins and phosphopeptides, can be released during gastrointestinal passage. It is also evident that peptides originating from food proteins should be taken into account as potential modulators of various regulatory processes in the body. The possible regulatory effects concern nutrient uptake (phosphopeptides, casomorphins), postprandial hormone secretion (casomorphins), immune defense (immunopeptides, casokinins, casomorphins) and neuroendocrine information transfer (casokinins). The advances in the research field of bioactive peptides are driven by a molecular understanding of biological processes, and analytical techniques are a critical component of this understanding. Different up-to-date methods, including peptide synthesis and immunochemistry, have been applied to the chemical characterization of bioactive peptides. Especially casein derived peptides have already found interesting applications, both as dietary supplements (phosphopeptides) and as pharmaceutical preparations (phosphopeptides, beta-casomorphins). The question of 'what kinds of bioactive peptides are beneficial and desirable as food constituents or as drugs' should be always carefully examined. However, the possibilities for the design of dietary products and 'natural' drugs look promising.
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Affiliation(s)
- E Schlimme
- Institut für Chemie und Physik, Bundesanstalt für Milchforschung, Kiel, Bundesrepublik Deutschland
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Affiliation(s)
- O Koldovský
- Department of Pediatrics, Steele Memorial Children's Research Center, Furrow Research Laboratory, University of Arizona, Tucson 85724
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Renlund S, Erlandsson I, Hellman U, Silberring J, Wernstedt C, Lindström L, Nyberg F. Micropurification and amino acid sequence of beta-casomorphin-8 in milk from a woman with postpartum psychosis. Peptides 1993; 14:1125-32. [PMID: 8134293 DOI: 10.1016/0196-9781(93)90165-d] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Milk was obtained from a woman with acute postpartum psychosis and with ongoing lactation. Defatted samples were subjected to micropurification and collected fractions were analyzed by means of their beta-casomorphin-8 immunoreactivity. Immunoreactive material with the same chromatographic properties as synthetic human beta-casomorphin-8 was determined by amino acid sequence analysis to be Tyr-Pro-Phe-Val-Glu-Pro-Ile-Pro. Its molecular mass was determined by fast atom bombardment-mass spectrometry to be 962.3 Da. These determinations, which ultimately identify the immunoreactive material as human beta-casomorphin-8, represent the first structural identification of a beta-casomorphin peptide from a body fluid.
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Affiliation(s)
- S Renlund
- Pharmacia LKB Biotechnology AB, Uppsala, Sweden
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Banks WA, Kastin AJ, Jaspan JB. Orally administered cyclo(His-Pro) reduces ethanol-induced narcosis in mice. Pharmacol Biochem Behav 1992; 43:939-41. [PMID: 1448489 DOI: 10.1016/0091-3057(92)90428-i] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cyclo(His-Pro) (cHP) is an endogenous, enzymatically resistant, biologically active peptide. We examined its ability to be absorbed after oral administration. cHP radioactively labeled with 125I (I-cHP) was fed to adult mice, and blood and tissue samples were taken 15-90 min later. Radioactivity quickly appeared in blood at levels about one half to one fourth those previously found after IV injection. The highest concentrations were in the kidney and liver, but the testes, muscle, lung, and brain also contained more radioactivity than was accounted for by their vascular spaces. Between 25-32% of the radioactivity recovered from blood 30 min after feeding eluted on high-performance liquid chromatography in the position of intact peptide. Oral cHP reversed ethanol-induced narcosis, an effect previously found to occur within the brain. These results show that cHP can be absorbed orally in amounts sufficient to affect the CNS.
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Affiliation(s)
- W A Banks
- Veterans Affairs Medical Center, New Orleans, LA 70146
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Abstract
Many biologically active polypeptides have been described in the milk of several species. Various functions for these polypeptides in addition to nutrition have been proposed in the maternal body and in the breast-fed infant. These polypeptides are derived from several sources and multiple factors control their secretion into milk as well as their fate in the mother and infant. An increasing body of evidence supports the concept that they may function physiologically.
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Affiliation(s)
- J R Britton
- Veterans Administration Medical Center, New Orleans, Louisiana
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