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Adeniyi-Ipadeola GO, Hankins JD, Kambal A, Zeng XL, Patil K, Poplaski V, Bomidi C, Nguyen-Phuc H, Grimm SL, Coarfa C, Stossi F, Crawford SE, Blutt SE, Speer AL, Estes MK, Ramani S. Infant and adult human intestinal enteroids are morphologically and functionally distinct. mBio 2024:e0131624. [PMID: 38953637 DOI: 10.1128/mbio.01316-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Accepted: 05/29/2024] [Indexed: 07/04/2024] Open
Abstract
Human intestinal enteroids (HIEs) are gaining recognition as physiologically relevant models of the intestinal epithelium. While HIEs from adults are used extensively in biomedical research, few studies have used HIEs from infants. Considering the dramatic developmental changes that occur during infancy, it is important to establish models that represent infant intestinal characteristics and physiological responses. We established jejunal HIEs from infant surgical samples and performed comparisons to jejunal HIEs from adults using RNA sequencing (RNA-Seq) and morphologic analyses. We then validated differences in key pathways through functional studies and determined whether these cultures recapitulate known features of the infant intestinal epithelium. RNA-Seq analysis showed significant differences in the transcriptome of infant and adult HIEs, including differences in genes and pathways associated with cell differentiation and proliferation, tissue development, lipid metabolism, innate immunity, and biological adhesion. Validating these results, we observed a higher abundance of cells expressing specific enterocyte, goblet cell, and enteroendocrine cell markers in differentiated infant HIE monolayers, and greater numbers of proliferative cells in undifferentiated 3D cultures. Compared to adult HIEs, infant HIEs portray characteristics of an immature gastrointestinal epithelium including significantly shorter cell height, lower epithelial barrier integrity, and lower innate immune responses to infection with an oral poliovirus vaccine. HIEs established from infant intestinal tissues reflect characteristics of the infant gut and are distinct from adult cultures. Our data support the use of infant HIEs as an ex vivo model to advance studies of infant-specific diseases and drug discovery for this population. IMPORTANCE Tissue or biopsy stem cell-derived human intestinal enteroids are increasingly recognized as physiologically relevant models of the human gastrointestinal epithelium. While enteroids from adults and fetal tissues have been extensively used for studying many infectious and non-infectious diseases, there are few reports on enteroids from infants. We show that infant enteroids exhibit both transcriptomic and morphological differences compared to adult cultures. They also differ in functional responses to barrier disruption and innate immune responses to infection, suggesting that infant and adult enteroids are distinct model systems. Considering the dramatic changes in body composition and physiology that begin during infancy, tools that appropriately reflect intestinal development and diseases are critical. Infant enteroids exhibit key features of the infant gastrointestinal epithelium. This study is significant in establishing infant enteroids as age-appropriate models for infant intestinal physiology, infant-specific diseases, and responses to pathogens.
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Affiliation(s)
- Grace O Adeniyi-Ipadeola
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Julia D Hankins
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Amal Kambal
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core, Houston, Texas, USA
| | - Xi-Lei Zeng
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core, Houston, Texas, USA
| | - Ketki Patil
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Victoria Poplaski
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Carolyn Bomidi
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Hoa Nguyen-Phuc
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Sandra L Grimm
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas, USA
- Center for Precision and Environmental Health, Baylor College of Medicine, Houston, Texas, USA
| | - Cristian Coarfa
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas, USA
- Center for Precision and Environmental Health, Baylor College of Medicine, Houston, Texas, USA
| | - Fabio Stossi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
- Gulf Coast Consortium Center for Advanced Microscopy and Image Informatics, Houston, Texas, USA
| | - Sue E Crawford
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Sarah E Blutt
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core, Houston, Texas, USA
| | - Allison L Speer
- Department of Pediatric Surgery, The University of Texas Health Science Center, Houston, Texas, USA
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core, Houston, Texas, USA
- Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Sasirekha Ramani
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
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Adeniyi-Ipadeola GO, Hankins JD, Kambal A, Zeng XL, Patil K, Poplaski V, Bomidi C, Nguyen-Phuc H, Grimm SL, Coarfa C, Stossi F, Crawford SE, Blutt SE, Speer AL, Estes MK, Ramani S. Infant and Adult Human Intestinal Enteroids are Morphologically and Functionally Distinct. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.19.541350. [PMID: 37292968 PMCID: PMC10245709 DOI: 10.1101/2023.05.19.541350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Background & Aims Human intestinal enteroids (HIEs) are gaining recognition as physiologically relevant models of the intestinal epithelium. While HIEs from adults are used extensively in biomedical research, few studies have used HIEs from infants. Considering the dramatic developmental changes that occur during infancy, it is important to establish models that represent infant intestinal characteristics and physiological responses. Methods We established jejunal HIEs from infant surgical samples and performed comparisons to jejunal HIEs from adults using RNA sequencing (RNA-Seq) and morphologic analyses. We validated differences in key pathways through functional studies and determined if these cultures recapitulate known features of the infant intestinal epithelium. Results RNA-Seq analysis showed significant differences in the transcriptome of infant and adult HIEs, including differences in genes and pathways associated with cell differentiation and proliferation, tissue development, lipid metabolism, innate immunity, and biological adhesion. Validating these results, we observed a higher abundance of cells expressing specific enterocyte, goblet cell and enteroendocrine cell markers in differentiated infant HIE monolayers, and greater numbers of proliferative cells in undifferentiated 3D cultures. Compared to adult HIEs, infant HIEs portray characteristics of an immature gastrointestinal epithelium including significantly shorter cell height, lower epithelial barrier integrity, and lower innate immune responses to infection with an oral poliovirus vaccine. Conclusions HIEs established from infant intestinal tissues reflect characteristics of the infant gut and are distinct from adult cultures. Our data support the use of infant HIEs as an ex-vivo model to advance studies of infant-specific diseases and drug discovery for this population.
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Affiliation(s)
| | - Julia D. Hankins
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Amal Kambal
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core
| | - Xi-Lei Zeng
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core
| | - Ketki Patil
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Victoria Poplaski
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Carolyn Bomidi
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Hoa Nguyen-Phuc
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Sandra L. Grimm
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX
- Center for Precision and Environmental Health, Baylor College of Medicine, Houston, TX
| | - Cristian Coarfa
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX
- Center for Precision and Environmental Health, Baylor College of Medicine, Houston, TX
| | - Fabio Stossi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
- Golf Coast Consortium Center for Advanced Microscopy and Image Informatics, Houston, TX
| | - Sue E. Crawford
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
| | - Sarah E. Blutt
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core
| | - Allison L. Speer
- Department of Pediatric Surgery, The University of Texas Health Science Center, Houston, TX
| | - Mary K. Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
- Texas Medical Center Digestive Diseases Center Gastrointestinal Experimental Model Systems (GEMS) Core
- Department of Medicine, Baylor College of Medicine, Houston, TX
| | - Sasirekha Ramani
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX
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Daily expression of sodium-dependent glucose cotransporter-1 protein in jejunum during rat ontogeny. ACTA ACUST UNITED AC 2019; 5:290-296. [PMID: 31528732 PMCID: PMC6737494 DOI: 10.1016/j.aninu.2019.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/17/2019] [Accepted: 04/02/2019] [Indexed: 11/21/2022]
Abstract
It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates, lipids and proteins, and the subsequent absorption of the hydrolyzed products, are evolutionary matched to dietary loads and feeding behaviors. In this study, we demonstrate that the protein expression of apically located sodium-dependent glucose cotransporter-1 (SGLT-1) throughout rat ontogeny is daily adjusted to afford glucose uptake when the load of this metabolically essential monosaccharide in the intestinal lumen is maximum. The jejunal expression of SGLT-1 protein in 14 one-day-old suckling pups was found to increase at dark and early light phase (P < 0.05), when they have a better access to mother milk. In weaning 21-d-old and juvenile 28-d-old rats, the cotransporter expression was high throughout the entire day (P < 0.05). Finally, adult 90-d-old rats showed a well-developed circadian rhythm for SGLT-1 protein (P < 0.05), whose expression increased at late light and dark phase when the highest intestinal glucose load was achieved. To our knowledge, these results are the first reporting the daily profile of SGLT-1 expression during rat early developmental stage and may contribute to understand the biological significance of a well-established molecular capacity to deal with the crucial increase of glucose load in the diet during the weaning process.
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Zalewska A. Developmental milestones in neonatal and juvenile C57Bl/6 mouse - Indications for the design of juvenile toxicity studies. Reprod Toxicol 2019; 88:91-128. [PMID: 31386883 DOI: 10.1016/j.reprotox.2019.07.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/24/2019] [Accepted: 07/19/2019] [Indexed: 01/08/2023]
Abstract
There is a growing demand for wild type mice and mouse models of disease that may be more representative of human conditions but there is little information on neonatal and juvenile mouse anatomy. This project produces sound and comprehensive histology background data on the developing neonatal mouse at different time points from Day 0 until Day 28. The work describes optimal methods for tissue harvesting, fixation and processing from the neonatal and juvenile mice which can be used in routine toxicology studies. A review of the available literature revealed inconsistencies in the developmental milestones reported in the mouse. Although it is true that the sequence of events during the development is virtually the same in mice and rats, important developmental milestones in the mouse often happen earlier than in the rat, and these species should not be used interchangeably.
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Affiliation(s)
- Aleksandra Zalewska
- Sequani Limited, Bromyard Road, Ledbury, HR8 1LH, Herefordshire, United Kingdom.
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5
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Crispel Y, Shaoul R, Khamaise R, Sabo E, Hochberg Z. Effect of weaning age on the small intestine mucosa of rats. Appl Physiol Nutr Metab 2019; 44:985-989. [PMID: 30689399 DOI: 10.1139/apnm-2018-0454] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Weaning of mammalian progeny is associated with a change in food composition and mother-offspring separation. Weaning results in a critical period of low voluntary feed intake, during which the animal is adapting to the starter diet. To evaluate the effects of weaning age on morphological changes that occur in the intestines of rats, we assessed intestinal histomorphometry and somatic growth in 21-days-old pups and 90-days-old mature rats that had been weaned early (day 16), normally (day 21), or late (day 26). Early weaning resulted in deeper crypts, lower villous/crypt ratio, and a smaller villous area on day 21. Crown-tail length correlated positively with the crypt depth and negatively with the villous/crypt ratio. At age 90 days, early weaned animals had shallower crypts, a greater villous/crypt ratio, and a smaller villous area compared with their normally weaned counterparts. The rats' crown-tail length correlated negatively with the crypt depth and positively with the villous/crypt ratio. Early weaning significantly affects the intestinal mucosa, which may impact food absorption and lead to differences in somatic growth compared with late weaning. Over time there may be a phase of compensation with increased villus height and crypt depth.
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Affiliation(s)
- Yonatan Crispel
- Neurophysiology Unit, Rambam Health Care Campus, Haifa, Israel.,Rappaport Family Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Ron Shaoul
- Rappaport Family Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel.,Pediatric Gastroenterology and Nutrition Institute, Ruth's Children's Hospital of Haifa, Rambam Medical Center, POB 9602, Haifa 31096, Israel
| | - Ranya Khamaise
- Rappaport Family Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Edmond Sabo
- Rappaport Family Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel.,Pathology Institute, Rambam Health Care Campus, Haifa, Israel
| | - Ze'ev Hochberg
- Rappaport Family Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
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6
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Downes NJ. Consideration of the Development of the Gastrointestinal Tract in the Choice of Species for Regulatory Juvenile Studies. Birth Defects Res 2017; 110:56-62. [PMID: 28872769 DOI: 10.1002/bdr2.1119] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/25/2017] [Accepted: 08/02/2017] [Indexed: 11/08/2022]
Abstract
Although the rat is close to being the automatic choice for regulatory juvenile toxicity studies, there are several shortcomings in this model. Choosing a species should take into serious consideration the importance of gastrointestinal tract development in the period before weaning as this may have a major effect on exposure. A comparison of the anatomical changes in the stomach and small intestine of mini-pig and rat show that the mini-pig is a far closer model for man than is the rat, although there are a few unusual aspects of small intestinal development in the mini-pig. Considerations of the development of the gastrointestinal tract and choice of species have the potential to affect safety assessment and should be a prime consideration when planning an investigation. Birth Defects Research 110:56-62, 2018. © 2017 Wiley Periodicals, Inc.
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Abstract
Necrotizing enterocolitis (NEC) is a devastating disease in premature infants with high case fatality and significant morbidity among survivors. Immaturity of intestinal host defenses predisposes the premature infant gut to injury. An abnormal bacterial colonization pattern with a deficiency of commensal bacteria may lead to a further breakdown of these host defense mechanisms, predisposing the infant to NEC. Here, we review the role of the innate and adaptive immune system in the pathophysiology of NEC.
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MESH Headings
- Adaptive Immunity
- Enterocolitis, Necrotizing/immunology
- Enterocolitis, Necrotizing/microbiology
- Enterocolitis, Necrotizing/physiopathology
- Evidence-Based Medicine
- Humans
- Immunity, Innate
- Infant, Premature
- Infant, Premature, Diseases/immunology
- Infant, Premature, Diseases/microbiology
- Infant, Premature, Diseases/physiopathology
- Intestinal Mucosa/immunology
- Intestinal Mucosa/microbiology
- Intestinal Mucosa/physiopathology
- Intestines/blood supply
- Intestines/immunology
- Intestines/physiopathology
- Milk, Human/immunology
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Affiliation(s)
- Timothy L Denning
- Institute for Biomedical Sciences, Georgia State University, Atlanta, GA
| | - Amina M Bhatia
- Department of Surgery, Emory University School of Medicine, Atlanta, GA
| | - Andrea F Kane
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA
| | - Ravi M Patel
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA
| | - Patricia W Denning
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA.
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8
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Halpern MD, Denning PW. The role of intestinal epithelial barrier function in the development of NEC. Tissue Barriers 2015; 3:e1000707. [PMID: 25927016 DOI: 10.1080/21688370.2014.1000707] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/16/2014] [Indexed: 12/12/2022] Open
Abstract
The intestinal epithelial barrier plays an important role in maintaining host health. Breakdown of intestinal barrier function is known to play a role in many diseases such as infectious enteritis, idiopathic inflammatory bowel disease, and neonatal inflammatory bowel diseases. Recently, increasing research has demonstrated the importance of understanding how intestinal epithelial barrier function develops in the premature neonate in order to develop strategies to promote its maturation. Optimizing intestinal barrier function is thought to be key to preventing neonatal inflammatory bowel diseases such as necrotizing enterocolitis. In this review, we will first summarize the key components of the intestinal epithelial barrier, what is known about its development, and how this may explain NEC pathogenesis. Finally, we will review what therapeutic strategies may be used to promote optimal development of neonatal intestinal barrier function in order to reduce the incidence and severity of NEC.
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Key Words
- AJ, adherens junctions
- AJC, apical junction complex
- BAs, bile acids; EGF, epidermal growth factor
- Bb, Bifidobacterium bifidum
- Bi, Bifidobacterium infantis
- EPO, erythropoietin; IFNγ, interferon gamma
- IEL, intestinal epithelial lymphocytes
- NEC, necrotizing enterocolitis
- NICU, neonatal intensive care unit
- Necrotizing enterocolitis (NEC)
- TCRγδ, T-cell receptor gamma-delta
- TGF-β, transforming growth factor-beta
- TJ, tight junctions
- TNFα, tumor necrosis factor alpha
- TPN, total parenteral nutrition
- apical junctional complex
- commensal bacteria
- intestinal epithelial barrier
- prematurity
- probiotics
- tight junctions
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Affiliation(s)
- Melissa D Halpern
- Department of Pediatrics; The University of Arizona ; Tucson, AZ USA
| | - Patricia W Denning
- Department of Pediatrics; Emory University School of Medicine ; Atlanta, GA USA
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Hinde K, Skibiel AL, Foster AB, Del Rosso L, Mendoza SP, Capitanio JP. Cortisol in mother's milk across lactation reflects maternal life history and predicts infant temperament. Behav Ecol 2014; 26:269-281. [PMID: 25713475 PMCID: PMC4309982 DOI: 10.1093/beheco/aru186] [Citation(s) in RCA: 181] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 09/04/2014] [Accepted: 09/18/2014] [Indexed: 12/25/2022] Open
Abstract
In monkeys, high cortisol and changes in cortisol levels in mother’s milk are associated with more nervous and less confident infants. Sons are more sensitive than are daughters to changes in cortisol in mother’s milk across lactation. Females that are earlier in their reproductive career tend to have higher cortisol in their milk. Mothers may be “programming” behaviorally cautious offspring that prioritize growth through cortisol signaling. The maternal environment exerts important influences on offspring mass/growth, metabolism, reproduction, neurobiology, immune function, and behavior among birds, insects, reptiles, fish, and mammals. For mammals, mother’s milk is an important physiological pathway for nutrient transfer and glucocorticoid signaling that potentially influences offspring growth and behavioral phenotype. Glucocorticoids in mother’s milk have been associated with offspring behavioral phenotype in several mammals, but studies have been handicapped by not simultaneously evaluating milk energy density and yield. This is problematic as milk glucocorticoids and nutrients likely have simultaneous effects on offspring phenotype. We investigated mother’s milk and infant temperament and growth in a cohort of rhesus macaque (Macaca mulatta) mother–infant dyads at the California National Primate Research Center (N = 108). Glucocorticoids in mother’s milk, independent of available milk energy, predicted a more Nervous, less Confident temperament in both sons and daughters. We additionally found sex differences in the windows of sensitivity and the magnitude of sensitivity to maternal-origin glucocorticoids. Lower parity mothers produced milk with higher cortisol concentrations. Lastly, higher cortisol concentrations in milk were associated with greater infant weight gain across time. Taken together, these results suggest that mothers with fewer somatic resources, even in captivity, may be “programming” through cortisol signaling, behaviorally cautious offspring that prioritize growth. Glucocorticoids ingested through milk may importantly contribute to the assimilation of available milk energy, development of temperament, and orchestrate, in part, the allocation of maternal milk energy between growth and behavioral phenotype.
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Affiliation(s)
- Katie Hinde
- Department of Human Evolutionary Biology, Harvard University , 11 Divinity Avenue, Cambridge, MA 02138 , USA , ; Brain, Mind, and Behavior Unit, California National Primate Research Center, University of Califoria, One Shields Avenue , Davis CA 95616 , USA , ; Nutrition Laboratory, Smithsonian National Zoological Park , 3001 Connecticut Avenue NW, Washington, DC 20008 , USA
| | - Amy L Skibiel
- Department of Human Evolutionary Biology, Harvard University , 11 Divinity Avenue, Cambridge, MA 02138 , USA , ; Department of Biological Sciences, Auburn University , 101 Rouse Life Science Rd, Auburn, AL, 36849 , USA
| | - Alison B Foster
- Division of Early Childhood, Mills College , 5000 MacArthur Blvd, Oakland, CA, 94613 , USA , and
| | - Laura Del Rosso
- Brain, Mind, and Behavior Unit, California National Primate Research Center, University of Califoria, One Shields Avenue , Davis CA 95616 , USA
| | - Sally P Mendoza
- Brain, Mind, and Behavior Unit, California National Primate Research Center, University of Califoria, One Shields Avenue , Davis CA 95616 , USA , ; Department of Psychology, University of California Davis , One Shields Ave, Davis, CA, 95616 , USA
| | - John P Capitanio
- Brain, Mind, and Behavior Unit, California National Primate Research Center, University of Califoria, One Shields Avenue , Davis CA 95616 , USA , ; Department of Psychology, University of California Davis , One Shields Ave, Davis, CA, 95616 , USA
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10
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Jakaitis BM, Denning PW. Commensal and probiotic bacteria may prevent NEC by maturing intestinal host defenses. PATHOPHYSIOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR PATHOPHYSIOLOGY 2014; 21:47-54. [PMID: 24440614 PMCID: PMC5424473 DOI: 10.1016/j.pathophys.2013.11.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Necrotizing enterocolitis (NEC) is a devastating disease of prematurity with significant morbidity and mortality. Immaturity of intestinal host defenses predisposes the premature infant gut to injury. An abnormal bacterial colonization pattern with a deficiency of commensal bacteria may lead to a further breakdown of these host defense mechanisms, predisposing the infant to NEC. The presence of probiotic and commensal bacteria within the gut has been shown to mature the intestinal defense system through a variety of mechanisms. We have shown that commensal and probiotic bacteria can promote intestinal host defenses by reducing apoptotic signaling, blocking inflammatory signaling, and maturing barrier function in immature intestinal epithelia. Future studies aimed at elucidating the mechanisms by which probiotic and commensal bacteria exert their effects will be critical to developing effective preventive therapies for NEC.
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Affiliation(s)
- Brett M Jakaitis
- Emory University School of Medicine, Department of Pediatrics, Division of Neonatology, Atlanta, GA, United States
| | - Patricia W Denning
- Emory University School of Medicine, Department of Pediatrics, Division of Neonatology, Atlanta, GA, United States.
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11
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MohanKumar K, Kaza N, Jagadeeswaran R, Garzon SA, Bansal A, Kurundkar AR, Namachivayam K, Remon JI, Bandepalli CR, Feng X, Weitkamp JH, Maheshwari A. Gut mucosal injury in neonates is marked by macrophage infiltration in contrast to pleomorphic infiltrates in adult: evidence from an animal model. Am J Physiol Gastrointest Liver Physiol 2012; 303:G93-102. [PMID: 22538401 PMCID: PMC3404576 DOI: 10.1152/ajpgi.00016.2012] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Necrotizing enterocolitis (NEC) is an inflammatory bowel necrosis of premature infants. In tissue samples of NEC, we identified numerous macrophages and a few neutrophils but not many lymphocytes. We hypothesized that these pathoanatomic characteristics of NEC represent a common tissue injury response of the gastrointestinal tract to a variety of insults at a specific stage of gut development. To evaluate developmental changes in mucosal inflammatory response, we used trinitrobenzene sulfonic acid (TNBS)-induced inflammation as a nonspecific insult and compared mucosal injury in newborn vs. adult mice. Enterocolitis was induced in 10-day-old pups and adult mice (n = 25 animals per group) by administering TNBS by gavage and enema. Leukocyte populations were enumerated in human NEC and in murine TNBS-enterocolitis using quantitative immunofluorescence. Chemokine expression was measured using quantitative polymerase chain reaction, immunoblots, and immunohistochemistry. Macrophage recruitment was investigated ex vivo using intestinal tissue-conditioned media and bone marrow-derived macrophages in a microchemotaxis assay. Similar to human NEC, TNBS enterocolitis in pups was marked by a macrophage-rich leukocyte infiltrate in affected tissue. In contrast, TNBS-enterocolitis in adult mice was associated with pleomorphic leukocyte infiltrates. Macrophage precursors were recruited to murine neonatal gastrointestinal tract by the chemokine CXCL5, a known chemoattractant for myeloid cells. We also demonstrated increased expression of CXCL5 in surgically resected tissue samples of human NEC, indicating that a similar pathway was active in NEC. We concluded that gut mucosal injury in the murine neonate is marked by a macrophage-rich leukocyte infiltrate, which contrasts with the pleomorphic leukocyte infiltrates in adult mice. In murine neonatal enterocolitis, macrophages were recruited to the inflamed gut mucosa by the chemokine CXCL5, indicating that CXCL5 and its cognate receptor CXCR2 merit further investigation as potential therapeutic targets in NEC.
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Affiliation(s)
- Krishnan MohanKumar
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease, ,Departments of 3Pediatrics and
| | - Niroop Kaza
- 4Pathology, University of Alabama at Birmingham, Birmingham, Alabama;
| | - Ramasamy Jagadeeswaran
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease,
| | | | | | | | - Kopperuncholan Namachivayam
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease,
| | - Juan I. Remon
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease,
| | - C. Rekha Bandepalli
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease,
| | - Xu Feng
- 4Pathology, University of Alabama at Birmingham, Birmingham, Alabama;
| | - Joern-Hendrik Weitkamp
- 6Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Akhil Maheshwari
- Departments of Pediatrics, 1Division of Neonatology and ,2Center for Neonatal and Pediatric Gastrointestinal Disease, ,7Pharmacology, University of Illinois at Chicago, Chicago, Illinois; ,Departments of 3Pediatrics and
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Probiotic bacteria induce maturation of intestinal claudin 3 expression and barrier function. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 180:626-35. [PMID: 22155109 DOI: 10.1016/j.ajpath.2011.10.025] [Citation(s) in RCA: 246] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 10/04/2011] [Accepted: 10/31/2011] [Indexed: 02/08/2023]
Abstract
An immature intestinal epithelial barrier may predispose infants and children to many intestinal inflammatory diseases, such as infectious enteritis, inflammatory bowel disease, and necrotizing enterocolitis. Understanding the factors that regulate gut barrier maturation may yield insight into strategies to prevent these intestinal diseases. The claudin family of tight junction proteins plays an important role in regulating epithelial paracellular permeability. Previous reports demonstrate that rodent intestinal barrier function matures during the first 3 weeks of life. We show that murine paracellular permeability markedly decreases during postnatal maturation, with the most significant change occurring between 2 and 3 weeks. Here we report for the first time that commensal bacterial colonization induces intestinal barrier function maturation by promoting claudin 3 expression. Neonatal mice raised on antibiotics or lacking the toll-like receptor adaptor protein MyD88 exhibit impaired barrier function and decreased claudin 3 expression. Furthermore, enteral administration of either live or heat-killed preparations of the probiotic Lactobacillus rhamnosus GG accelerates intestinal barrier maturation and induces claudin 3 expression. However, live Lactobacillus rhamnosus GG increases mortality. Taken together, these results support a vital role for intestinal flora in the maturation of intestinal barrier function. Probiotics may prevent intestinal inflammatory diseases by regulating intestinal tight junction protein expression and barrier function. The use of heat-killed probiotics may provide therapeutic benefit while minimizing adverse effects.
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Henare SJ, Mellor DJ, Lentle RG, Moughan PJ. An appraisal of the strengths and weaknesses of newborn and juvenile rat models for researching gastrointestinal development. Lab Anim 2008; 42:231-45. [DOI: 10.1258/la.2007.007034] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Research on the impact of bioactive compounds on the development and functional maturation of the gastrointestinal (GI) tract using newborn and juvenile rats has greatly contributed to the knowledge of GI physiology and to the improved clinical management of both premature and full-term newborns. Of the animal models available, two types have been described for use with young rats – maintenance models and substitution models. Maintenance models are those in which the young are reared with the dam and therefore benefit from continuation of natural nutrition and maternal care. Substitution models are those in which the young are reared in the absence of the dam using artificially formulated milk delivered by various means into specific GI sites. In this review, we describe these models and their operation, and discuss the strengths and weaknesses of each. Attention is also given to questions of scientific validity and some animal welfare issues raised by the use of these models.
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Affiliation(s)
- S J Henare
- Riddet Centre, Massey University, Private Bag 11 222, Palmerston North, New Zealand
| | - D J Mellor
- Riddet Centre, Massey University, Private Bag 11 222, Palmerston North, New Zealand
- Institute of Food Nutrition and Human Health, Massey University, Palmerston North, New Zealand
| | - R G Lentle
- Institute of Food Nutrition and Human Health, Massey University, Palmerston North, New Zealand
| | - P J Moughan
- Riddet Centre, Massey University, Private Bag 11 222, Palmerston North, New Zealand
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Walthall K, Cappon GD, Hurtt ME, Zoetis T. Postnatal development of the gastrointestinal system: a species comparison. ACTA ACUST UNITED AC 2005; 74:132-56. [PMID: 15834902 DOI: 10.1002/bdrb.20040] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Karen Walthall
- Aclairo Pharmaceutical Development Group, Inc., Sterling, Virginia, USA
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Abstract
An essential process for fatty acid digestion, absorption and assimilation is the constant replacement of mature intestinal epithelial cells by differentiating stem cells. Free fatty acids (FFA) and PYY may act in concert to alter mucosal cell differentiation through the cytoskeletal-extracellular matrix interactions. PYY induced expression of tetraspanins and intestinal fatty acid binding protein (I-FABP) may be part of a mechanism whereby FFA modulate expression of differentiation dependent proteins in the mucosa. This modulation provides a means for FFA to act as signal molecules in the feedback regulation of their own assimilation.
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Affiliation(s)
- Gregory W Aponte
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720-3104, USA.
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16
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Dvorak B, McWilliam DL, Williams CS, Dominguez JA, Machen NW, McCuskey RS, Philipps AF. Artificial formula induces precocious maturation of the small intestine of artificially reared suckling rats. J Pediatr Gastroenterol Nutr 2000; 31:162-9. [PMID: 10941968 DOI: 10.1097/00005176-200008000-00013] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND The artificially reared rat model was used successfully to study the effect of nutrition during the early postnatal period on growth and development of the neonate. Overgrowth and morphologic changes of the gastrointestinal tract are known consequences of artificial rearing. The major goal of our study was to elucidate whether artificial rearing-enhanced gut development is caused by artificial diet or by gastrostomy and the artificial rearing technique itself. METHODS Suckling rats at day 8 of age underwent intragastric cannulation and were machine fed either a cow's milk-based artificial rat's milk substitute or pooled rat's milk for 4 days. Dam-fed littermates served as a control. RESULTS Body growth did not differ in the three experimental groups. In rats receiving rat's milk substitute, small intestinal wet weight was approximately 60% greater than in rats fed rat's milk or control rats. Additionally, the entire small intestine was approximately 20% longer in the rat's milk substitute group. Morphologically, rat's milk substitute-fed pups demonstrated significantly greater intestinal villus length and crypt depth compared with rat's milk-fed or control rats. Jejunum and midjejunum of the rat's milk and control groups did not differ in these parameters. Intestinal sucrase activity of rat's milk substitute-fed rats was significantly elevated compared with rat's milk-fed rats or control animals. CONCLUSIONS These results indicate that cow's milk-based formula, not gastrostomy or artificial feeding technique, is a principal cause of the small intestine overgrowth and precocious maturation of some intestinal functions observed in artificially reared sucklings.
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Affiliation(s)
- B Dvorak
- Department of Pediatrics and Steele Memorial Children's Research Center, University of Arizona, Tucson 85724-5073, USA
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Bhan MK, Bhandari N. The role of zinc and vitamin A in persistent diarrhea among infants and young children. J Pediatr Gastroenterol Nutr 1998; 26:446-53. [PMID: 9552143 DOI: 10.1097/00005176-199804000-00016] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- M K Bhan
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi
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Roy SK, Tomkins AM, Akramuzzaman SM, Behrens RH, Haider R, Mahalanabis D, Fuchs G. Randomised controlled trial of zinc supplementation in malnourished Bangladeshi children with acute diarrhoea. Arch Dis Child 1997; 77:196-200. [PMID: 9370894 PMCID: PMC1717301 DOI: 10.1136/adc.77.3.196] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished.
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Affiliation(s)
- S K Roy
- Clinical Sciences Division, International Centre for Diarrhoeal Diseases Research, Dhaka, Bangladesh
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Durant M, Gargosky SE, Dahlstrom KA, Hellman BH, Castillo RO. Regulation of postnatal intestinal maturation by growth hormone: studies in rats with isolated growth hormone deficiency. Pediatr Res 1996; 40:88-93. [PMID: 8798252 DOI: 10.1203/00006450-199607000-00016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
During the 3rd wk of postnatal life in the rat, dramatic maturational changes occur in the structure and function of the small intestine, enabling the animal to make the transition from milk to solid food. To investigate the role of GH in the regulation of this complex process, we studied postnatal intestinal maturation in the spontaneous dwarf rat, a strain of Sprague-Dawley rats with an autosomal recessive mutation in the GH gene resulting in complete but isolated GH deficiency. GH-deficient and GH-normal littermates were studied at d 7 and 14 (suckling) and d 23 (postweaned). The body weight of GH-deficient animals was inhibited by 60% at each age. Longitudinal growth of the small intestine was not inhibited, suggesting that longitudinal small bowel growth is independent of GH regulation. Mucosal cell mass was significantly lower in GH deficiency at all ages studied, and digestive hydrolase capacity per cm of intestine was significantly lower in GH-deficient postweaned animals. However, epithelial cell mass increased markedly in association with weaning and the maturation of lactase, sucrase, and aminooligopeptidase proceeded normally in GH deficiency. These data suggest that, although GH is not required for normal postnatal intestinal maturation, the mucosal epithelial hypoplasia found in GH-deficient animals suggests that GH or GH-dependent factors act as an intestinal mucosal growth factor whose function is to promote the homeostatic or steady-state regulation of mucosal epithelial growth.
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Affiliation(s)
- M Durant
- Department of Pediatrics, Stanford University School of Medicine, California 94305, USA
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20
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Sazawal S, Black RE, Bhan MK, Bhandari N, Sinha A, Jalla S. Zinc supplementation in young children with acute diarrhea in India. N Engl J Med 1995; 333:839-44. [PMID: 7651474 DOI: 10.1056/nejm199509283331304] [Citation(s) in RCA: 248] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND In developing countries the duration and severity of diarrheal illnesses are greatest among infants and young children with malnutrition and impaired immune status, both factors that may be associated with zinc deficiency. In children with severe zinc deficiency, diarrhea is common and responds quickly to zinc supplementation. METHODS To evaluate the effects of daily supplementation with 20 mg of elemental zinc on the duration and severity of acute diarrhea, we conducted a double-blind, randomized, controlled trial involving 937 children, 6 to 35 months of age, in New Delhi, India. All the children also received oral rehydration therapy and vitamin supplements. RESULTS Among the children who received zinc supplementation, there was a 23 percent reduction (95 percent confidence interval, 12 percent to 32 percent) in the risk of continued diarrhea. Estimates of the likelihood of recovery according to the day of zinc supplementation revealed a reduction of 7 percent (95 percent confidence interval, -9 percent to +22 percent) in the risk of continued diarrhea during days 1 through 3 and a reduction of 38 percent (95 percent confidence interval, 27 percent to 48 percent) after day 3. When zinc supplementation was initiated within three days of the onset of diarrhea, there was a 39 percent reduction (95 percent confidence interval, 7 percent to 61 percent) in the proportion of episodes lasting more than seven days. In the zinc-supplementation group there was a decrease of 39 percent (95 percent confidence interval, 6 percent to 70 percent) in the mean number of watery stools per day (P = 0.02) and a decrease of 21 percent (95 percent confidence interval, 10 percent to 31 percent) in the number of days with watery diarrhea. The reductions in the duration and severity of diarrhea were greater in children with stunted growth than in those with normal growth. CONCLUSION For infants and young children with acute diarrhea, zinc supplementation results in clinically important reductions in the duration and severity of diarrhea.
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Affiliation(s)
- S Sazawal
- Department of International Health, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, MD, USA
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21
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Affiliation(s)
- S K Roy
- International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
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22
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Reeds PJ, Burrin DG, Davis TA, Fiorotto ML. Postnatal growth of gut and muscle: competitors or collaborators. Proc Nutr Soc 1993; 52:57-67. [PMID: 8493277 DOI: 10.1079/pns19930037] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- P J Reeds
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Houston, Texas 77030
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23
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Le Huerou I, Guilloteau P, Wicker C, Mouats A, Chayvialle JA, Bernard C, Burton J, Toullec R, Puigserver A. Activity distribution of seven digestive enzymes along small intestine in calves during development and weaning. Dig Dis Sci 1992; 37:40-6. [PMID: 1728529 DOI: 10.1007/bf01308340] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Ten groups of calves were used to study the changes in activity levels and distribution of seven hydrolases in the intestinal mucosa during development and weaning. The calves in the first group were sacrificed at birth while those in the remaining nine groups were either milk-fed until slaughter on days 2, 7, 28, 56, 70, and 119; or weaned between days 28 and 56 and then slaughtered on days 56, 70, and 119, respectively. The small intestine was immediately cut off and divided into five segments, ie, duodenum, proximal jejunum, median jejunum, distal jejunum, and ileum. In the milk-fed animals, the activity levels of aminopeptidases A and N, alkaline phosphatase, lactase, and isomaltase were maximum at 2 days of age, and then declined sharply between days 2 and 7 but did not change significantly thereafter. By contrast, the maltase activity increased between days 7 and 119, while no sucrase activity was detected. Weaning resulted in a decrease in the activity of lactase and an increase in that of aminopeptidase N, maltase, and isomaltase. The distribution of all these enzymes along the small intestine was slightly influenced by age but not at all by weaning.
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Affiliation(s)
- I Le Huerou
- Institut National de la Recherche Agronomique, Rennes, France
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24
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Abstracts of Communications. Proc Nutr Soc 1991. [DOI: 10.1079/pns19910017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Affiliation(s)
- P J Reeds
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030
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Demant P, Oomen LC, Oudshoorn-Snoek M. Genetics of tumor susceptibility in the mouse: MHC and non-MHC genes. Adv Cancer Res 1989; 53:117-79. [PMID: 2678946 DOI: 10.1016/s0065-230x(08)60281-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- P Demant
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam
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