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Muñoz Forti K, Weisman GA, Jasmer KJ. Cell type-specific transforming growth factor-β (TGF-β) signaling in the regulation of salivary gland fibrosis and regeneration. J Oral Biol Craniofac Res 2024; 14:257-272. [PMID: 38559587 PMCID: PMC10979288 DOI: 10.1016/j.jobcr.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/13/2024] [Accepted: 03/09/2024] [Indexed: 04/04/2024] Open
Abstract
Salivary gland damage and hypofunction result from various disorders, including autoimmune Sjögren's disease (SjD) and IgG4-related disease (IgG4-RD), as well as a side effect of radiotherapy for treating head and neck cancers. There are no therapeutic strategies to prevent the loss of salivary gland function in these disorders nor facilitate functional salivary gland regeneration. However, ongoing aquaporin-1 gene therapy trials to restore saliva flow show promise. To identify and develop novel therapeutic targets, we must better understand the cell-specific signaling processes involved in salivary gland regeneration. Transforming growth factor-β (TGF-β) signaling is essential to tissue fibrosis, a major endpoint in salivary gland degeneration, which develops in the salivary glands of patients with SjD, IgG4-RD, and radiation-induced damage. Though the deposition and remodeling of extracellular matrix proteins are essential to repair salivary gland damage, pathological fibrosis results in tissue hardening and chronic salivary gland dysfunction orchestrated by multiple cell types, including fibroblasts, myofibroblasts, endothelial cells, stromal cells, and lymphocytes, macrophages, and other immune cell populations. This review is focused on the role of TGF-β signaling in the development of salivary gland fibrosis and the potential for targeting TGF-β as a novel therapeutic approach to regenerate functional salivary glands. The studies presented highlight the divergent roles of TGF-β signaling in salivary gland development and dysfunction and illuminate specific cell populations in damaged or diseased salivary glands that mediate the effects of TGF-β. Overall, these studies strongly support the premise that blocking TGF-β signaling holds promise for the regeneration of functional salivary glands.
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Affiliation(s)
- Kevin Muñoz Forti
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
| | - Gary A. Weisman
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
| | - Kimberly J. Jasmer
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
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Phelps HM, Warner BW. Intestinal adaptation and rehabilitation. Semin Pediatr Surg 2023; 32:151314. [PMID: 37276784 DOI: 10.1016/j.sempedsurg.2023.151314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Massive intestinal resection is a regrettably necessary but life-saving intervention for progressive or fulminant necrotizing enterocolitis (NEC). However, the resultant short bowel syndrome (SBS) poses its own array of challenges and complications. Within hours of such an abrupt loss of intestinal length, the intestine begins to adapt. Our ability to understand this process of intestinal adaptation has proven critical in our ability to clinically treat the challenging problem of short bowel syndrome. This review first highlights key data relating to intestinal adaptation including structural and functional changes, biochemical regulation, and other factors affecting the magnitude of intestinal adaptation responses. We then focus on intestinal rehabilitation as it relates to strategies to enhance intestinal adaptation while meeting nutritional needs and preventing complications of parenteral nutrition.
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Affiliation(s)
- Hannah M Phelps
- Division of Pediatric Surgery, Department of Surgery, Washington University in St. Louis School of Medicine, 9901 Wohl Hospital, Campus Box 8109, St. Louis, MO 63110, USA.
| | - Brad W Warner
- Division of Pediatric Surgery, Department of Surgery, Washington University in St. Louis School of Medicine, 9901 Wohl Hospital, Campus Box 8109, St. Louis, MO 63110, USA
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Onufer EJ, Aladegbami B, Imai T, Seiler K, Bajinting A, Courtney C, Sutton S, Bustos A, Yao J, Yeh CH, Sescleifer A, Wang LV, Guo J, Warner BW. EGFR in enterocytes & endothelium and HIF1α in enterocytes are dispensable for massive small bowel resection induced angiogenesis. PLoS One 2020; 15:e0236964. [PMID: 32931498 PMCID: PMC7491746 DOI: 10.1371/journal.pone.0236964] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 07/16/2020] [Indexed: 12/15/2022] Open
Abstract
Background Short bowel syndrome (SBS) results from significant loss of small intestinal length. In response to this loss, adaptation occurs, with Epidermal Growth Factor Receptor (EGFR) being a key driver. Besides enhanced enterocyte proliferation, we have revealed that adaptation is associated with angiogenesis. Further, we have found that small bowel resection (SBR) is associated with diminished oxygen delivery and elevated levels of hypoxia-inducible factor 1-alpha (HIF1α). Methods We ablated EGFR in the epithelium and endothelium as well as HIF1α in the epithelium, ostensibly the most hypoxic element. Using these mice, we determined the effects of these genetic manipulations on intestinal blood flow after SBR using photoacoustic microscopy (PAM), intestinal adaptation and angiogenic responses. Then, given that endothelial cells require a stromal support cell for efficient vascularization, we ablated EGFR expression in intestinal subepithelial myofibroblasts (ISEMFs) to determine its effects on angiogenesis in a microfluidic model of human small intestine. Results Despite immediate increased demand in oxygen extraction fraction measured by PAM in all mouse lines, were no differences in enterocyte and endothelial cell EGFR knockouts or enterocyte HIF1α knockouts by POD3. Submucosal capillary density was also unchanged by POD7 in all mouse lines. Additionally, EGFR silencing in ISEMFs did not impact vascular network development in a microfluidic device of human small intestine. Conclusions Overall, despite the importance of EGFR in facilitating intestinal adaptation after SBR, it had no impact on angiogenesis in three cell types–enterocytes, endothelial cells, and ISEMFs. Epithelial ablation of HIF1α also had no impact on angiogenesis in the setting of SBS.
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Affiliation(s)
- Emily J. Onufer
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Bola Aladegbami
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Toru Imai
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States of America
- Department of Electrical Engineering, Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, United States of America
| | - Kristen Seiler
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Adam Bajinting
- Saint Louis University School of Medicine, St. Louis, MO, United States of America
| | - Cathleen Courtney
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Stephanie Sutton
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Aiza Bustos
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Junjie Yao
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States of America
| | - Cheng-Hung Yeh
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States of America
| | - Anne Sescleifer
- Saint Louis University School of Medicine, St. Louis, MO, United States of America
| | - Lihong V. Wang
- Department of Electrical Engineering, Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, United States of America
| | - Jun Guo
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
| | - Brad W. Warner
- Division of Pediatric Surgery, Department of Surgery, St. Louis Children’s Hospital, Washington University in St. Louis School of Medicine, St. Louis, MO, United States of America
- * E-mail:
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4
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Channabasappa N, Girouard S, Nguyen V, Piper H. Enteral Nutrition in Pediatric Short-Bowel Syndrome. Nutr Clin Pract 2020; 35:848-854. [PMID: 32815247 DOI: 10.1002/ncp.10565] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pediatric intestinal failure (IF) is the critical reduction of intestinal mass or function below the amount necessary for normal growth in children. Short-bowel syndrome (SBS) is the most common cause of IF in infants and children and is caused by intestinal resection. Enteral autonomy and freedom from parenteral nutrition is the mainstay of nutrition management in SBS. The goal is to achieve intestinal adaptation while maintaining proper growth and development. Treatment is variable, and there remains a paucity of evidence to draw well-informed conclusions for the care of individuals in this complex population. Physiological principles of enteral nutrition and practical recommendations for advancing the diet of patients with pediatric SBS are presented. Emerging trends in nutrition management, such as the growing interest in blending diets and the impact on SBS, are reviewed. Finally, the influence of the microbiome on enteral tolerance and small bowel bacterial overgrowth are considered.
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Affiliation(s)
- Nandini Channabasappa
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sara Girouard
- Department of Clinical Nutrition, Children's Health of Dallas, Dallas, Texas, USA
| | - Van Nguyen
- Department of Gastroenterology, Children's Health of Dallas, Dallas, Texas, USA
| | - Hannah Piper
- Division of Pediatric Surgery, Unversity of British Columbia, Vancouver, British Columbia, Canada
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5
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Olieman J, Kastelijn W. Nutritional Feeding Strategies in Pediatric Intestinal Failure. Nutrients 2020; 12:E177. [PMID: 31936393 PMCID: PMC7019898 DOI: 10.3390/nu12010177] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/31/2019] [Accepted: 01/04/2020] [Indexed: 12/20/2022] Open
Abstract
Intestinal failure is defined as a critical reduction of the gut mass or function, below the minimum needed to absorb nutrients and fluids. The ultimate goal in intestinal failure is to promote bowel adaptation and reach enteral autonomy while a healthy growth and development is maintained. The condition is heterogeneous and complex. Therefore, recommendations for the type and duration of parenteral, enteral, and oral nutrition are variable, with the child's age as an additional key factor. The aim of this review is to provide an overview of nutritional feeding strategies in this heterogeneous population. Different perspectives on nutritional management, nutrition and adaptation, and microbiome and nutrition will be discussed.
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Affiliation(s)
- Joanne Olieman
- Department of Internal Medicine, Division of Dietetics, Erasmus MC, University Medical Center Rotterdam, Wytemaweg 40, 3015 GD Rotterdam, The Netherlands;
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Goulet O, Abi Nader E, Pigneur B, Lambe C. Short Bowel Syndrome as the Leading Cause of Intestinal Failure in Early Life: Some Insights into the Management. Pediatr Gastroenterol Hepatol Nutr 2019; 22:303-329. [PMID: 31338307 PMCID: PMC6629594 DOI: 10.5223/pghn.2019.22.4.303] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/11/2019] [Indexed: 12/13/2022] Open
Abstract
Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.
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Affiliation(s)
- Olivier Goulet
- Department of Pediatric Gastroenterology-Hepatology-Nutrition, National Reference Center for Rare Digestive Diseases, Pediatric Intestinal Failure Rehabilitation Center, Hôpital Necker-Enfants Malades, University Sorbonne-Paris-Cité Paris Descartes Medical School, Paris, France
| | - Elie Abi Nader
- Department of Pediatric Gastroenterology-Hepatology-Nutrition, National Reference Center for Rare Digestive Diseases, Pediatric Intestinal Failure Rehabilitation Center, Hôpital Necker-Enfants Malades, University Sorbonne-Paris-Cité Paris Descartes Medical School, Paris, France
| | - Bénédicte Pigneur
- Department of Pediatric Gastroenterology-Hepatology-Nutrition, National Reference Center for Rare Digestive Diseases, Pediatric Intestinal Failure Rehabilitation Center, Hôpital Necker-Enfants Malades, University Sorbonne-Paris-Cité Paris Descartes Medical School, Paris, France
| | - Cécile Lambe
- Department of Pediatric Gastroenterology-Hepatology-Nutrition, National Reference Center for Rare Digestive Diseases, Pediatric Intestinal Failure Rehabilitation Center, Hôpital Necker-Enfants Malades, University Sorbonne-Paris-Cité Paris Descartes Medical School, Paris, France
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7
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Courtney CM, Onufer EJ, Seiler KM, Warner BW. An anatomic approach to understanding mechanisms of intestinal adaptation. Semin Pediatr Surg 2018; 27:229-236. [PMID: 30342597 DOI: 10.1053/j.sempedsurg.2018.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Cathleen M Courtney
- Division of Pediatric Surgery, St. Louis Children's Hospital, One Children's Place, Suite 6110, St. Louis, 63110 MO, USA; Department of Surgery, Washington University School of Medicine, St. Louis, USA
| | - Emily J Onufer
- Division of Pediatric Surgery, St. Louis Children's Hospital, One Children's Place, Suite 6110, St. Louis, 63110 MO, USA; Department of Surgery, Washington University School of Medicine, St. Louis, USA
| | - Kristen M Seiler
- Division of Pediatric Surgery, St. Louis Children's Hospital, One Children's Place, Suite 6110, St. Louis, 63110 MO, USA; Department of Surgery, Washington University School of Medicine, St. Louis, USA
| | - Brad W Warner
- Division of Pediatric Surgery, St. Louis Children's Hospital, One Children's Place, Suite 6110, St. Louis, 63110 MO, USA; Department of Surgery, Washington University School of Medicine, St. Louis, USA.
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8
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Isani M, Illingworth L, Herman E, Schmidt M, Barron L, Bowling J, Elizee M, Bai I, Gayer C, Grishin A, Erwin CR, Ford HR, Warner BW. Soybean-derived recombinant human epidermal growth factor protects against experimental necrotizing enterocolitis. J Pediatr Surg 2018; 53:1203-1207. [PMID: 29636182 DOI: 10.1016/j.jpedsurg.2018.02.084] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 02/27/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND Epidermal Growth Factor (EGF) reduces necrotizing enterocolitis (NEC). However, its high cost virtually prohibits clinical use. To reduce cost, soybean expressing human EGF was developed. Here we report effectiveness of soybean-derived EGF in experimental NEC. METHODS Newborn rats were subjected to the NEC-inducing regimen of formula feeding and hypoxia. Formula was supplemented with extract from EGF-expressing or empty soybeans. NEC pathology was determined microscopically. Localization of tight junction proteins JAM-A and ZO-1 was examined by immunofluorescence and levels of mucosal COX-2 and iNOS mRNAs by real time PCR. RESULTS Soybean extract amounts corresponding to 150μg/kg/day EGF caused considerable mortality, whereas those corresponding to 75μg/kg/day EGF were well tolerated. There was no significant difference in NEC scores between animals fed plain formula and formula supplemented with empty soybean extract. Soybean-EGF-supplemented formula at 75μg/kg/day EGF significantly decreased NEC, attenuated dissociation of JAM-A and ZO-1 proteins from tight junctions, and reduced intestinal expression of COX-2 and iNOS mRNAs. CONCLUSION Supplementation with soybean-expressed EGF significantly decreased NEC in the rat model. Soybean-expressed EGF may provide an economical solution for EGF administration and prophylaxis of clinical NEC.
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MESH Headings
- Animals
- Animals, Newborn
- Cyclooxygenase 2/metabolism
- Disease Models, Animal
- Enterocolitis, Necrotizing/pathology
- Enterocolitis, Necrotizing/prevention & control
- Epidermal Growth Factor/therapeutic use
- Humans
- Infant Formula
- Infant, Newborn
- Infant, Premature
- Infant, Premature, Diseases/pathology
- Infant, Premature, Diseases/prevention & control
- Intestinal Mucosa/metabolism
- Intestines/pathology
- Junctional Adhesion Molecules/metabolism
- Nitric Oxide Synthase Type II/metabolism
- Plant Extracts/therapeutic use
- Protective Agents/therapeutic use
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Recombinant Proteins/therapeutic use
- Glycine max
- Zonula Occludens Proteins/metabolism
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Affiliation(s)
- Mubina Isani
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA
| | - Laura Illingworth
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA
| | - Eliot Herman
- University of Arizona School of Plant Sciences, Tucson, AZ
| | - Monica Schmidt
- University of Arizona School of Plant Sciences, Tucson, AZ
| | - Lauren Barron
- Division of Pediatric Surgery, Washington University, St. Louis, MO
| | - Jordan Bowling
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA
| | - Melissa Elizee
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA
| | - Iris Bai
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA
| | - Christopher Gayer
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Anatoly Grishin
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | | | - Henri R Ford
- Division of Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Brad W Warner
- Division of Pediatric Surgery, Washington University, St. Louis, MO.
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9
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Abstract
PURPOSE OF REVIEW Necrotizing enterocolitis (NEC) is a devastating disease that predominately affects premature neonates. The pathogenesis of NEC is multifactorial and poorly understood. Risk factors include low birth weight, formula-feeding, hypoxic/ischemic insults, and microbial dysbiosis. This review focuses on our current understanding of the diagnosis, management, and pathogenesis of NEC. RECENT FINDINGS Recent findings identify specific mucosal cell types as potential therapeutic targets in NEC. Despite a broadly accepted view that bacterial colonization plays a key role in NEC, characteristics of bacterial populations associated with this disease remain elusive. The use of probiotics such as lactobacilli and bifidobacteria has been studied in numerous trials, but there is a lack of consensus regarding specific strains and dosing. Although growth factors found in breast milk such as epidermal growth factor and heparin-binding epidermal growth factor may be useful in disease prevention, developing new therapeutic interventions in NEC critically depends on better understanding of its pathogenesis. SUMMARY NEC is a leading cause of morbidity and mortality in premature neonates. Recent data confirm that growth factors and certain bacteria may offer protection against NEC. Further studies are needed to better understand the complex pathogenesis of NEC.
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10
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Norsa L, Nicastro E, Di Giorgio A, Lacaille F, D'Antiga L. Prevention and Treatment of Intestinal Failure-Associated Liver Disease in Children. Nutrients 2018; 10:nu10060664. [PMID: 29882922 PMCID: PMC6024802 DOI: 10.3390/nu10060664] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 01/01/2023] Open
Abstract
Intestinal failure-associated liver disease (IFALD) is a threatening complication for children on long-term parenteral nutrition because of intestinal failure. When progressive and intractable, it may jeopardize intestinal rehabilitation and lead to combined liver and intestinal transplantation. The institution of dedicated intestinal failure centers has dramatically decreased the incidence of such complication. IFALD may rapidly fade away if very early management aimed at preventing progression to end-stage liver disease is provided. In this review, we address the etiology and risk factors of IFALD in order to introduce pillars of prevention (nutritional management and catheter-related infections control). The latest evidence of therapeutic strategies, such as medical and surgical treatments, is also discussed.
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Affiliation(s)
- Lorenzo Norsa
- Pediatric Gastroenterology Hepatology and Nutrition, Ospedale Papa Giovanni XXIII, 24127 Bergamo, Italy.
| | - Emanuele Nicastro
- Pediatric Gastroenterology Hepatology and Nutrition, Ospedale Papa Giovanni XXIII, 24127 Bergamo, Italy.
| | - Angelo Di Giorgio
- Pediatric Gastroenterology Hepatology and Nutrition, Ospedale Papa Giovanni XXIII, 24127 Bergamo, Italy.
| | - Florence Lacaille
- Pediatric Gastroenterology Hepatology and Nutrition, Hôpital Necker Enfants Malades, 75015 Paris, France.
| | - Lorenzo D'Antiga
- Pediatric Gastroenterology Hepatology and Nutrition, Ospedale Papa Giovanni XXIII, 24127 Bergamo, Italy.
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12
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Warner BW. The Pathogenesis of Resection-Associated Intestinal Adaptation. Cell Mol Gastroenterol Hepatol 2016; 2:429-438. [PMID: 27722191 PMCID: PMC5042605 DOI: 10.1016/j.jcmgh.2016.05.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 05/06/2016] [Indexed: 12/14/2022]
Abstract
After massive small-bowel resection, the remnant bowel compensates by a process termed adaptation. Adaptation is characterized by villus elongation and crypt deepening, which increases the capacity for absorption and digestion per unit length. The mechanisms/mediators of this important response are multiple. The purpose of this review is to highlight the major basic contributions in elucidating a more comprehensive understanding of this process.
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Affiliation(s)
- Brad W. Warner
- Correspondence Address correspondence to: Brad W. Warner, MD, Washington University School of Medicine, St. Louis Children's Hospital, One Children's Place, Suite 5s40, St. Louis, Missouri 63110. fax: (314) 454-2442.Washington University School of MedicineSt. Louis Children's HospitalOne Children's PlaceSuite 5s40St. LouisMissouri 63110
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13
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Lim DW, Wales PW, Turner JM, Bigam DL, Brubaker PL. On the horizon: trophic peptide growth factors as therapy for neonatal short bowel syndrome. Expert Opin Ther Targets 2016; 20:819-30. [DOI: 10.1517/14728222.2016.1146695] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- David W. Lim
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
| | - Paul W. Wales
- Department of Surgery, University of Toronto & Hospital for Sick Children, Toronto, ON, Canada
| | - Justine M. Turner
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - David L. Bigam
- Department of Surgery, University of Alberta, Edmonton, AB, Canada
| | - Patricia L. Brubaker
- Departments of Physiology and Medicine, University of Toronto, Toronto, ON, Canada
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14
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Lim JC, Golden JM, Ford HR. Pathogenesis of neonatal necrotizing enterocolitis. Pediatr Surg Int 2015; 31:509-18. [PMID: 25854935 DOI: 10.1007/s00383-015-3697-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/23/2015] [Indexed: 12/22/2022]
Abstract
Although necrotizing enterocolitis (NEC) is the most lethal gastrointestinal disease in the neonatal population, its pathogenesis is poorly understood. Risk factors include prematurity, bacterial colonization, and formula feeding. This review examines how mucosal injury permits opportunistic pathogens to breach the gut barrier and incite an inflammatory response that leads to sustained overproduction of mediators such as nitric oxide and its potent adduct, peroxynitrite. These mediators not only exacerbate the initial mucosal injury, but they also suppress the intestinal repair mechanisms, which further compromises the gut barrier and culminates in bacterial translocation, sepsis, and full-blown NEC.
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Affiliation(s)
- Joanna C Lim
- Division of Pediatric Surgery, Children's Hospital Los Angeles, 4650 Sunset Blvd., Mailstop #72, Los Angeles, CA, 90027, USA
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15
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Abstract
Intestinal adaptation is a natural compensatory process that occurs following extensive intestinal resection, whereby structural and functional changes in the intestine improve nutrient and fluid absorption in the remnant bowel. In animal studies, postresection structural adaptations include bowel lengthening and thickening and increases in villus height and crypt depth. Functional changes include increased nutrient transporter expression, accelerated crypt cell differentiation, and slowed transit time. In adult humans, data regarding adaptive changes are sparse, and the mechanisms underlying intestinal adaptation remain to be fully elucidated. Several factors influence the degree of intestinal adaptation that occurs post resection, including site and extent of resection, luminal stimulation with enteral nutrients, and intestinotrophic factors. Two intestinotrophic growth factors, the glucagon-like peptide 2 analog teduglutide and recombinant growth hormone (somatropin), are now approved for clinical use in patients with short bowel syndrome (SBS). Both agents enhance fluid absorption and decrease requirements for parenteral nutrition (PN) and/or intravenous fluid. Intestinal adaptation has been thought to be limited to the first 1-2 years following resection in humans. However, recent data suggest that a significant proportion of adult patients with SBS can achieve enteral autonomy, even after many years of PN dependence, particularly with trophic stimulation.
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Affiliation(s)
- Kelly A Tappenden
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois
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16
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Keswani SG, Balaji S, Le LD, Leung A, Parvadia JK, Frischer J, Yamano S, Taichman N, Crombleholme TM. Role of salivary vascular endothelial growth factor (VEGF) in palatal mucosal wound healing. Wound Repair Regen 2013; 21:554-62. [PMID: 23758212 DOI: 10.1111/wrr.12065] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 04/30/2013] [Indexed: 12/27/2022]
Abstract
The mucosa of alimentary tract heals more rapidly than cutaneous wounds. The underlying mechanisms of this enhanced healing have not been completely elucidated. Constant exposure to salivary growth factors has been shown to play a critical role in mucosal homeostasis and tissue repair. Angiogenesis also has an essential role in successful wound repair. One of the main angiogenic growth factors, vascular endothelial growth factor (VEGF), has a pleiotropic role in tissue repair via neovascularization, reepithelialization, and regulation of extracellular matrix. We have previously reported a critical role for salivary VEGF in bowel adaptation after small bowel resection. We hypothesize that salivary VEGF is an essential stimulus for oral mucosal tissue repair, and use the murine palatal wound model to test our hypothesis. In a loss-of-function experiment, we removed the primary source of VEGF production through selective submandibular gland (SMG) sialoadenectomy in a murine model and observed the effects on wound closure and neovascularization. We then performed a selective loss-of-function experiment using the protein VEGF-Trap to inhibit salivary VEGF. In a gain-of-function experiment, we supplemented oral VEGF following SMG sialoadenectomy. After SMG sialoadenectomy, there was significant reduction in salivary VEGF level, wound closure, and vessel density. Lower levels of salivary VEGF were correlated with impaired neovascularization and reepithelialization. The selective blockade of VEGF using VEGF-Trap resulted in a similar impairment in wound healing and neovascularization. The sole supplementation of oral VEGF after SMG sialoadenectomy rescued the impaired wound healing phenotype and restored neovascularization to normal levels. These data show a novel role for salivary-VEGF in mucosal wound healing, and provide a basis for the development of novel therapeutics aimed at augmenting wound repair of the oral mucosa, as well as wounds at other sites in the alimentary tract.
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Affiliation(s)
- Sundeep G Keswani
- Center for Molecular Fetal Therapy, Division of Pediatric General, Thoracic, and Fetal Surgery, Cincinnati Children's Hospital Medical Center and The University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA.
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Rowland KJ, Choi PM, Warner BW. The role of growth factors in intestinal regeneration and repair in necrotizing enterocolitis. Semin Pediatr Surg 2013; 22:101-11. [PMID: 23611614 PMCID: PMC3635039 DOI: 10.1053/j.sempedsurg.2013.01.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Necrotizing enterocolitis (NEC) is a devastating intestinal disease resulting in major neonatal morbidity and mortality. The pathology is poorly understood, and the means of preventing and treating NEC are limited. Several endogenous growth factors have been identified as having important roles in intestinal growth as well as aiding intestinal repair from injury or inflammation. In this review, we will discuss several growth factors as mediators of intestinal regeneration and repair as well as potential therapeutic agents for NEC.
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Affiliation(s)
| | | | - Brad W. Warner
- Correspondence: Brad W. Warner, M.D. St. Louis Children's Hospital One Children's Place; Suite 5S40 St. Louis MO 63110 (314) 454-6022 - Phone (314) 454-2442 – Fax
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Abstract
Intestinal failure (IF) is a condition in which severe intestinal malabsorption mandates artificial nutrition through a parenteral route. Causes of severe protracted IF include short bowel syndrome, congenital diseases of enterocyte development, and severe motility disorders (total or subtotal aganglionosis or chronic intestinal pseudo-obstruction syndrome). IF can result in nutritional failure, defined as the long-term failure to nourish a child by natural or artificial means. Today, IF-associated liver disease is the most common cause of parenteral nutrition (PN) failure, but catheter-related sepsis and extensive vascular thrombosis may also jeopardize the health of those receiving PN. For a child with nutritional failure, intestinal transplantation, often in the form of a composite visceral graft, offers the only chance for long-term survival. The management of IF requires a multidisciplinary approach. There have been a number of recent advances in both medical and surgical treatments of IF. In particular, new intestinal lengthening techniques and the use of PN formulas rich in fish oil both have resulted in decreased rates of severe complications of IF and its treatments. In addition, better awareness of the risks and benefits of intestinal transplantation have resulted in better patient selection, and ultimately in improved patient survival, hence restricting the indication to transplantation only to patients with nutritional failure and no other chance to survive.
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Abstract
Adaptation is an important compensatory response to environmental cues resulting in enhanced survival. In the gut, the abrupt loss of intestinal length is characterized by increased rates of enterocyte proliferation and apoptosis and culminates in adaptive villus and crypt growth. In the development of an academic pediatric surgical career, adaptation is also an important compensatory response to survive the ever changing research, clinical, and economic environment. The ability to adapt in both situations is critical for patients and a legacy of pediatric surgical contributions to advance our knowledge of multiple conditions and diseases.
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Goulet O, Olieman J, Ksiazyk J, Spolidoro J, Tibboe D, Köhler H, Yagci RV, Falconer J, Grimble G, Beattie RM. Neonatal short bowel syndrome as a model of intestinal failure: physiological background for enteral feeding. Clin Nutr 2012; 32:162-71. [PMID: 23159212 DOI: 10.1016/j.clnu.2012.09.007] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Revised: 08/26/2012] [Accepted: 09/12/2012] [Indexed: 01/17/2023]
Abstract
Intestinal failure (IF) is a well identified clinical condition, which is characterised by the reduction of functional gut capacity below the minimum needed for adequate digestion and absorption of nutrients for normal growth in children. Short bowel syndrome (SBS) is the leading cause of IF in neonates, infants and young children usually as a result of extensive intestinal resection during the neonatal period. Simultaneously maintaining optimal nutritional status and achieving intestinal adaptation is a clinical challenge in short bowel patients. Both growth and development of the child as well as gut adaptation should be considered synergistically as primary outcome parameters. Enteral nutrition (EN) can be introduced orally and/or by tube feeding (TF). Several controversies over nutritional treatment of children with SBS related intestinal failure remain. As reported from different centres around the world, most practices are more "experienced based" rather than "evidence based". This is partly due to the small number of patients with this condition. This review (based on a consensus) discusses the physiological principles and nutritional management, including the type of diet and route of delivery. Perspectives in optimizing intestinal adaptation and reducing the consequences of small intestinal bacterial overgrowth are also discussed.
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Affiliation(s)
- O Goulet
- Department of Pediatric Gastroenterology-Hepatology and Nutrition, Reference Center for Rare Digestive Diseases, Intestinal Failure Rehabilitation Center, Hôpital Necker-Enfants Malades, University of Paris Descartes, France.
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21
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Rowland KJ, McMellen ME, Wakeman D, Wandu WS, Erwin CR, Warner BW. Enterocyte expression of epidermal growth factor receptor is not required for intestinal adaptation in response to massive small bowel resection. J Pediatr Surg 2012; 47:1748-53. [PMID: 22974617 PMCID: PMC3443391 DOI: 10.1016/j.jpedsurg.2012.03.089] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 03/06/2012] [Indexed: 02/07/2023]
Abstract
PURPOSE Intestinal adaptation after massive small bowel resection (SBR) permits improved absorption of enteral nutrition despite significant loss of bowel length. Epidermal growth factor (EGF) and its receptor (EGFR) have previously been established to play major roles in the pathogenesis of adaptation. This study tested the hypothesis that EGFR signaling within the epithelial cell compartment (enterocytes) is required for intestinal adaptation. METHODS We developed a tamoxifen-inducible Villin-Cre/LoxP recombinant system for enterocyte-directed EGFR deletion using EGFR-floxed mice. Epidermal growth factor receptor-null mice and wild-type littermates underwent either 50% proximal SBR or sham operation. Ileal tissue was harvested on postoperative day 7. To assess for adaptation, villus height and crypt depth as well as rates of crypt cell proliferation and apoptosis were measured. RESULTS Adaptation after SBR occurred normally, as demonstrated by significant increases in villus height, crypt depth, and crypt proliferative and apoptotic index in both the wild-type and EGFR-null mice. CONCLUSION Enterocyte EGFR expression is not required for the adaptation response to massive SBR. This novel finding suggests that enterocyte proliferation during adaptation is regulated by EGFR signaling in cells other than enterocytes, perhaps within the mesenchymal cell compartment of the bowel wall via factor(s) that are presently unknown.
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Affiliation(s)
| | | | | | | | | | - Brad W. Warner
- Correspondence: Brad W. Warner, M.D., St. Louis Children's Hospital, One Children's Place; Suite 5S40, St. Louis MO 63110, (314) 454-6022 - Phone, (314) 454-2442 – Fax,
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22
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Hitch MC, Leinicke JA, Wakeman D, Guo J, Erwin CR, Rowland KJ, Merrick EC, Heuckeroth RO, Warner BW. Ret heterozygous mice have enhanced intestinal adaptation after massive small bowel resection. Am J Physiol Gastrointest Liver Physiol 2012; 302:G1143-50. [PMID: 22421622 PMCID: PMC3362098 DOI: 10.1152/ajpgi.00296.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Intestinal adaptation is an important compensatory response to massive small bowel resection (SBR) and occurs because of a proliferative stimulus to crypt enterocytes by poorly understood mechanisms. Recent studies suggest the enteric nervous system (ENS) influences enterocyte proliferation. We, therefore, sought to determine whether ENS dysfunction alters resection-induced adaptation responses. Ret+/- mice with abnormal ENS function and wild-type (WT) littermates underwent sham surgery or 50% SBR. After 7 days, ileal morphology, enterocyte proliferation, apoptosis, and selected signaling proteins were characterized. Crypt depth and villus height were equivalent at baseline in WT and Ret+/- mice. In contrast after SBR, Ret+/- mice had longer villi (Ret+/- 426.7 ± 46.0 μm vs. WT 306.5 ± 7.7 μm, P < 0.001) and deeper crypts (Ret+/- 119 ± 3.4 μm vs. WT 82.4 ± 3.1 μm, P < 0.001) than WT. Crypt enterocyte proliferation was higher in Ret+/- (48.8 ± 1.3%) than WT (39.9 ± 2.1%; P < 0.001) after resection, but apoptosis rates were similar. Remnant bowel of Ret+/- mice also had higher levels of glucagon-like peptide 2 (6.2-fold, P = 0.005) and amphiregulin (4.6-fold, P < 0.001) mRNA after SBR, but serum glucagon-like peptide 2 protein levels were equal in WT and Ret+/- mice, and there was no evidence of increased c-Fos nuclear localization in submucosal neurons. Western blot confirmed higher crypt epidermal growth factor receptor (EGFR) protein levels (1.44-fold; P < 0.001) and more phosphorylated EGFR (2-fold; P = 0.003) in Ret+/- than WT mice after SBR. These data suggest that Ret heterozygosity enhances intestinal adaptation after massive SBR, likely via enhanced EGFR signaling. Reducing Ret activity or altering ENS function may provide a novel strategy to enhance adaptation attenuating morbidity in patients with short bowel syndrome.
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Affiliation(s)
- Meredith C. Hitch
- 1Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, and
| | - Jennifer A. Leinicke
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
| | - Derek Wakeman
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
| | - Jun Guo
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
| | - Chris R. Erwin
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
| | - Kathryn J. Rowland
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
| | - Ellen C. Merrick
- 1Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, and
| | - Robert O. Heuckeroth
- 1Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology, and Nutrition, and ,3Department of Developmental, Regenerative and Stem Cell Biology, Washington University School of Medicine, St. Louis, Missouri
| | - Brad W. Warner
- 2Department of Surgery, Division of Pediatric Surgery, Washington University School of Medicine, St. Louis Children's Hospital, and
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23
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Ma K, Hu Y, Smith DE. Influence of fed-fasted state on intestinal PEPT1 expression and in vivo pharmacokinetics of glycylsarcosine in wild-type and Pept1 knockout mice. Pharm Res 2011; 29:535-45. [PMID: 21904935 DOI: 10.1007/s11095-011-0580-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Accepted: 08/26/2011] [Indexed: 11/28/2022]
Abstract
PURPOSE To determine if fasting would affect the intestinal expression and in vivo functional activity of PEPT1 as determined after oral dosing of the dipeptide glycylsarcosine (GlySar). METHODS Systemic exposure and tissue distribution studies were performed in wild-type and Pept1 knockout mice, under fed and fasted conditions, following both intravenous and oral doses of [(14)C]GlySar at 5 nmol/g body weight. Intestinal PEPT1 expression was evaluated by real-time PCR and immunoblot analyses. RESULTS We found that expression of PEPT1 protein in the small intestine was increased ~2-fold in wild-type mice during fasted as compared to fed conditions. In agreement, systemic exposure and peak plasma concentrations of orally administered GlySar were 40 and 65% greater, respectively, in wild-type mice during fasted vs. fed state. No significant differences were observed between fed and fasted animals during PEPT1 ablation. Tissue distribution of GlySar was unchanged after oral dosing for all four treatment groups. CONCLUSIONS As little as 16 h of fasting can cause significant upregulation of PEPT1 protein expression in the small intestine, which then translates into a significant increase in in vivo oral absorption of GlySar.
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Affiliation(s)
- Ke Ma
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, USA
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24
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McMellen ME, Wakeman D, Longshore SW, McDuffie LA, Warner BW. Growth factors: possible roles for clinical management of the short bowel syndrome. Semin Pediatr Surg 2010; 19:35-43. [PMID: 20123272 PMCID: PMC2891767 DOI: 10.1053/j.sempedsurg.2009.11.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The structural and functional changes during intestinal adaptation are necessary to compensate for the sudden loss of digestive and absorptive capacity after massive intestinal resection. When the adaptive response is inadequate, short bowel syndrome (SBS) ensues and patients are left with the requirement for parenteral nutrition and its associated morbidities. Several hormones have been studied as potential enhancers of the adaptation process. The effects of growth hormone, insulin-like growth factor-1, epidermal growth factor, and glucagon-like peptide 2 on adaptation have been studied extensively in animal models. In addition, growth hormone and glucagon-like peptide 2 have shown promise for the treatment of SBS in clinical trials in human beings. Several lesser studied hormones, including leptin, corticosteroids, thyroxine, testosterone, and estradiol, are also discussed.
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Affiliation(s)
- Mark E. McMellen
- Division of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO, USA
| | - Derek Wakeman
- Division of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO, USA
| | - Shannon W. Longshore
- Department of Surgery, University of California, Davis Medical Center, Sacramento, CA, USA
| | - Lucas A. McDuffie
- School of Medicine, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Brad W. Warner
- Division of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO, USA,Correspondence: Brad W. Warner, MD Division of Pediatric Surgery St. Louis Children's Hospital, One Children's Place Suite 5S40, St. Louis, MO 63110 Tel.: 1 314 454 6022 Fax: 1 314 454 2442
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25
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Nair RR, Warner BB, Warner BW. Role of epidermal growth factor and other growth factors in the prevention of necrotizing enterocolitis. Semin Perinatol 2008; 32:107-13. [PMID: 18346534 DOI: 10.1053/j.semperi.2008.01.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Necrotizing enterocolitis (NEC) presents as the most common gastrointestinal emergency during the neonatal period and results in ulceration and necrosis of the distal small intestine and proximal colon. The etiology of NEC remains unknown. Based on the complexity of gut development, multiple growth factors and cytokines may be needed to synergistically support the developing gut. Epidermal growth factor (EGF) has been shown to play an important role in intestinal cell restitution, proliferation, and maturation. EGF is found in abundant quantities in many fluids, including the gastrointestinal tract, amniotic fluid, breast milk, and saliva. Preliminary clinical trials using EGF in neonates diagnosed with NEC have been shown to promote repair of intestinal epithelium. Additionally, other growth factors are also emerging as potential treatment modalities, including erythropoietin, granulocyte colony stimulating factor, and heparin-binding EGF. The role of EGF and other growth factors in the pathogenesis and prevention of NEC will be reviewed.
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Affiliation(s)
- Rajalakshmi R Nair
- Division of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO 63110, USA
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26
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Parvadia JK, Keswani SG, Vaikunth S, Maldonado AR, Marwan A, Stehr W, Erwin C, Uzvolgyi E, Warner BW, Yamano S, Taichman N, Crombleholme TM. Role of VEGF in small bowel adaptation after resection: the adaptive response is angiogenesis dependent. Am J Physiol Gastrointest Liver Physiol 2007; 293:G591-8. [PMID: 17585015 DOI: 10.1152/ajpgi.00572.2006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Previous work in our group has demonstrated that mouse salivary gland has the highest concentration of salivary-derived VEGF protein compared with other organs and is essential for normal palatal mucosal wound healing. We hypothesize that salivary VEGF plays an important role in maintaining the integrity of the gastrointestinal mucosa following small bowel resection (SBR). Thirty-five 8- to 10-wk-old C57BL/6 female mice were divided into seven treatment groups: 1) sham (transaction and anastomosis, n = 5); 2) SBR (n = 8); 3) sialoadenectomy and small bowel resection (SAL+SBR, n = 8); 4) sialoadenectomy and small bowel resection with EGF supplementation (SAL+SBR+EGF, n = 9); 5) sialoadenectomy and small bowel resection with VEGF supplementation (SAL+SBR+VEGF, n = 9); 6) sialoadenectomy and small bowel resection supplemented with EGF and VEGF (SAL+ SBR+VEGF+EGF, n = 6); 7) selective inhibition of VEGF in the submandibular gland by Ad-VEGF-Trap following small bowel resection (Ad-VEGF-Trap+SBR, n = 7). Adaptation was after 3 days by ileal villus height and crypt depth. The microvascular response was evaluated by CD31 immunostaining and for villus-vessel area ratio by FITC-labeled von Willebrand factor immunostaining. The adaptive response after SBR was significantly attenuated in the SAL group in terms of villus height (250.4 +/- 8.816 vs. 310 +/- 19.35, P = 0.01) and crypt depth (100.021 +/- 4.025 vs. 120.541 +/- 2.82, P = 0.01). This response was partially corrected by orogastric VEGF or EGF alone. The adaptive response was completely restored when both were administered together, suggesting that salivary VEGF and EGF both contribute to intestinal adaptation. VEGF increases the vascular density (6.4 +/- 0.29 vs. 6.1 +/- 0.29 vs. 5.96 +/- 0.20) and villus-vessel area ratio (0.713 +/- 0.01 vs. 0.73 +/- 0.01) in the adapting bowel. Supplementation of both EGF and VEGF fully rescues adaptation, suggesting that the adaptive response may be dependent on VEGF-driven angiogenesis. These results support a previously unrecognized role for VEGF in the small bowel adaptive response.
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Affiliation(s)
- Jignesh K Parvadia
- Center for Molecular and Fetal Therapy, Division of Pediatric General, Thoracic, and Fetal Surgery, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA
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27
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Martin GR, Beck PL, Sigalet DL. Gut hormones, and short bowel syndrome: The enigmatic role of glucagon-like peptide-2 in the regulation of intestinal adaptation. World J Gastroenterol 2006; 12:4117-29. [PMID: 16830359 PMCID: PMC4087358 DOI: 10.3748/wjg.v12.i26.4117] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Short bowel syndrome (SBS) refers to the malabsorption of nutrients, water, and essential vitamins as a result of disease or surgical removal of parts of the small intestine. The most common reasons for removing part of the small intestine are due to surgical intervention for the treatment of either Crohn's disease or necrotizing enterocolitis. Intestinal adaptation following resection may take weeks to months to be achieved, thus nutritional support requires a variety of therapeutic measures, which include parenteral nutrition. Improper nutrition management can leave the SBS patient malnourished and/or dehydrated, which can be life threatening. The development of therapeutic strategies that reduce both the complications and medical costs associated with SBS/long-term parenteral nutrition while enhancing the intestinal adaptive response would be valuable.
Currently, therapeutic options available for the treatment of SBS are limited. There are many potential stimulators of intestinal adaptation including peptide hormones, growth factors, and neuronally-derived components. Glucagon-like peptide-2 (GLP-2) is one potential treatment for gastrointestinal disorders associated with insufficient mucosal function. A significant body of evidence demonstrates that GLP-2 is a trophic hormone that plays an important role in controlling intestinal adaptation. Recent data from clinical trials demonstrate that GLP-2 is safe, well-tolerated, and promotes intestinal growth in SBS patients. However, the mechanism of action and the localization of the glucagon-like peptide-2 receptor (GLP-2R) remains an enigma. This review summarizes the role of a number of mucosal-derived factors that might be involved with intestinal adaptation processes; however, this discussion primarily examines the physiology, mechanism of action, and utility of GLP-2 in the regulation of intestinal mucosal growth.
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Affiliation(s)
- G-R Martin
- Department of Gastrointestinal Sciences, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW., Calgary, Alberta T2N 4N1, Canada.
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28
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Warner BW, Erwin CR. Critical roles for EGF receptor signaling during resection-induced intestinal adaptation. J Pediatr Gastroenterol Nutr 2006; 43 Suppl 1:S68-73. [PMID: 16819405 DOI: 10.1097/01.mpg.0000226393.87106.da] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The adaptation response of the remnant gut to massive intestinal resection represents a mitogenic signal involving all bowel wall layers. In the mucosa, this response results in taller villi, deeper crypts, and enhanced enterocyte turnover as gauged by greater rates of both proliferation and apoptosis. Although the exact mechanisms and mediators of this important compensatory response remain incompletely understood, work from this laboratory over the past decade has illuminated a crucial role for intact receptor signaling for a robust response. Using a murine model for intestinal resection, transgenic, null and mutant mouse strains have provided unique experimental paradigms to dissect molecular mechanisms for epidermal growth factor (EGF) receptor-directed influence on adaptation. Stimulation of this receptor is linked with a magnified adaptation response, whereas attenuation of the activity of this receptor is associated with impaired adaptation. EGF receptor activation and expression are both elevated in enterocytes after resection, and salivary levels of EGF-the major ligand for the EGF receptor-are increased. In addition to stimulation of enterocyte proliferation, EGF receptor signaling prevents the typical increase in rates of enterocyte apoptosis, probably by affecting the ratio of expression of both pro- and anti-apoptotic Bcl-2 family members. The key to optimizing care for patients with short gut syndrome will necessarily follow a thorough understanding of intestinal adaptation responses.
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Affiliation(s)
- Brad W Warner
- Division of Pediatric General and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, OH 45229-3039, USA.
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29
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Bernal NP, Stehr W, Profitt S, Erwin CR, Warner BW. Combined pharmacotherapy that increases proliferation and decreases apoptosis optimally enhances intestinal adaptation. J Pediatr Surg 2006; 41:719-24; discussion 719-24. [PMID: 16567183 DOI: 10.1016/j.jpedsurg.2005.12.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Adaptation after massive small bowel resection (SBR) is associated with increased rates of enterocyte proliferation (P) and apoptosis (A). In the present study, we sought to determine the effect of dual therapy designed to increase P and simultaneously reduce A. METHODS C57Bl/6 mice underwent a 50% small bowel resection (SBR) or sham operation, and then received an inhibitor of apoptosis (pan-caspase inhibitor), a stimulus for proliferation (epidermal growth factor; EGF), a combination, or vehicle control. After 3 days, adaptive morphology (villus height, crypt depth) and rates of enterocyte turnover (proliferation and apoptosis) were measured in the remnant ileum. RESULTS Adaptation in controls and treated with the inhibitor was similar. EGF-treated mice demonstrated an even greater adaptive response. Combined therapy with the inhibitor and EGF resulted in maximal adaptation as gauged by the greatest increases in villus height and crypt depth and ratio of rates of P to A. CONCLUSION The capacity for adaptation following massive SBR is maintained via tight regulation of cell production and death. Pharmacologic intervention directed at increasing enterocyte proliferation while simultaneously decreasing apoptosis augments adaptation greater than either intervention alone and may provide a useful strategy to clinically amplify adaptation.
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Affiliation(s)
- Nicole P Bernal
- Division of Pediatric General and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
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30
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Bernal NP, Stehr W, Coyle R, Erwin CR, Warner BW. Epidermal growth factor receptor signaling regulates Bax and Bcl-w expression and apoptotic responses during intestinal adaptation in mice. Gastroenterology 2006; 130:412-23. [PMID: 16472596 DOI: 10.1053/j.gastro.2005.11.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Accepted: 11/02/2005] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Normal intestinal adaptation to massive small-bowel resection requires intact epidermal growth factor receptor signaling and consists of increased enterocyte proliferation and apoptosis. Although emphasis has been placed on understanding the regulation of proliferation, few studies have evaluated the mechanism and contribution of apoptosis to the adaptation response. We sought to test the hypothesis that epidermal growth factor receptor signaling regulates specific Bcl-2 family members (Bax and Bcl-w) to direct apoptosis and adaptation after massive small-bowel resection. METHODS Laser capture microdissection microscopy permitted measurement of Bax and Bcl-w messenger RNA expression in crypt and villus enterocytes in control conditions and under epidermal growth factor receptor-inhibited (waved-2 mice) or stimulated (epidermal growth factor transgenic mice) conditions after a 50% small-bowel resection or sham operation. Resection-induced adaptation was then studied in Bax-null and Bcl-w-null mice under control circumstances and after epidermal growth factor receptor stimulation. RESULTS When compared with Bcl-w, the most significant expression changes were observed with Bax and took place within crypt enterocytes. Epidermal growth factor receptor stimulation resulted in a decreased ratio of Bax to Bcl-w expression and decreased rates of apoptosis. Bax-null mice had no apoptosis response to small-bowel resection and displayed an amplified adaptation response to the administration of epidermal growth factor. Bcl-w-null mice had poor survival and impaired adaptation to small-bowel resection, an effect that was rescued by crossbreeding these mice with epidermal growth factor transgenic mice. CONCLUSIONS The crypt expression of Bax and Bcl-w is influenced by epidermal growth factor receptor signaling and is key for the regulation of apoptosis. Epidermal growth factor receptor stimulation, coupled with apoptosis inhibition, may provide a novel strategy to amplify adaptation responses in patients after massive intestinal loss.
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Affiliation(s)
- Nicole P Bernal
- Division of Pediatric and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
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31
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Warner BW, Warner BB. Role of epidermal growth factor in the pathogenesis of neonatal necrotizing enterocolitis. Semin Pediatr Surg 2005; 14:175-80. [PMID: 16084405 DOI: 10.1053/j.sempedsurg.2005.05.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Neonatal necrotizing enterocolitis (NEC) is an increasingly frequent condition encountered in premature infants for which the etiology is not well understood. Epidermal growth factor (EGF) is abundant in many fluids bathing the fetal and neonatal gastrointestinal tract, including amniotic fluid, saliva, and breast milk. EGF is acknowledged to be important for normal intestinal development as well as repair following injury to the gastrointestinal mucosa. There appears to be mounting evidence to support a possible link between deficient EGF production and the development of NEC. The relevant evidence for the role of EGF in intestinal development and mucosal repair, as well as its potential involvement in the genesis of NEC will be reviewed.
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Affiliation(s)
- Brad W Warner
- Division of Pediatric and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA.
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Sigalet DL, Martin GR, Butzner JD, Buret A, Meddings JB. A pilot study of the use of epidermal growth factor in pediatric short bowel syndrome. J Pediatr Surg 2005; 40:763-8. [PMID: 15937810 DOI: 10.1016/j.jpedsurg.2005.01.038] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND This study examined the effects of enterally administered epidermal growth factor (EGF) on nutrient absorption and tolerance of enteral feeds in pediatric patients with short bowel syndrome (SBS). METHODS Patients identified with severe SBS (<25% bowel length predicted for age) were prospectively enrolled in treatment using human recombinant EGF (1-53); 100 microg/kg per day given mixed with enteral feeds and patients were treated for 6 weeks. End points followed were patient weight, tolerance of enteral feeds, nutrient absorption, and intestinal permeability as determined using carbohydrate probes and hematologic values for liver function parameters. RESULTS Five patients were treated with EGF; all showed a significant improvement in carbohydrate absorption (3-0 methylglucose): absorption 24.7% +/- 9.7% pretreatment vs 34.1% +/- 13.8% posttreatment and improved tolerance of enteral feeds (enteral energy as % of total energy, 25% +/- 28% pretreatment vs 36% +/- 24% posttreatment; mean +/- SD; P < .05 by Wilcoxon's signed rank test). Epidermal growth factor treatment was not associated with significant changes in intestinal permeability, the rate of weight gain, or liver function tests. During the treatment phase, no patients developed episodes of sepsis; however, within 2 weeks of discontinuation of EGF treatment, 3 patients developed septic episodes. No adverse effects of EGF administration were noted. CONCLUSIONS These results suggest that enteral treatment with EGF in pediatric SBS improves nutrient absorption, increases tolerance with enteral feeds, and may improve the infection rate. Further studies exploring treatment strategies including the timing and duration of EGF administration are indicated.
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Affiliation(s)
- David L Sigalet
- GI Research Group, University of Calgary, Calgary, Alberta, Canada TZT SC7.
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Jarboe MD, Juno RJ, Bernal NP, Knott AW, Zhang Y, Erwin CR, Warner BW. Bax deficiency rescues resection-induced enterocyte apoptosis in mice with perturbed EGF receptor function. Surgery 2004; 136:121-6. [PMID: 15300170 DOI: 10.1016/j.surg.2004.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Adaptation after massive smallbowel resection (SBR) is associated with increased cell turnover, increased rates of enterocyte proliferation, and apoptosis. Epidermal growth factor receptor (EGFR) inhibition attenuates adaptation and increases apoptosis. Intestinal levels of bax appear to correlate with EGFR signaling. This study tested the hypothesis that bax is required for the exaggerated postresection apoptosis induced by perturbed EGFR signaling. METHODS Waved-2 mice with impaired EGFR signaling were crossbred with bax-null mice. Offspring were subjected to either 50% proximal SBR or sham operation (bowel transection and reanastomosis). After 7 days, parameters of adaptation (villus height, wet weight), proliferation (% Ki-67 immunostaining of crypt cells), and apoptosis (# apoptotic bodies per crypt) were recorded in the remnant ileum. RESULTS Enterocyte apoptosis was increased in waved-2 mice and prevented in bax-null mice after SBR. The accelerated apoptosis in the waved-2 mice was rescued in the context of deficient bax expression. Other parameters of adaptation were restored in the bax-null/waved-2 mice. CONCLUSION Bax is required for the induction of postresection enterocyte apoptosis. Defective EGFR signaling augments resection-induced enterocyte apoptosis via a mechanism that also requires bax expression. These data implicate a link between EGFR signaling and bax in the genesis of postresection apoptosis and adaptation.
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Affiliation(s)
- Marcus D Jarboe
- Division of Pediatric Surgery, Cincinnati Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Abstract
As the number of extremely low-birth-weight infants increases,necrotizing enterocolitis remains a critical eminent problem. Supplementation of enteral feeds with biologically active substances normally present in breast milk, such as epidermal growth factor, seems to be a logical and safe way to reduce the incidence of intestinal inflammation and necrotizing enterocolitis. Continuing basic research and clinical studies are essential before epidermal growth factor can be introduced as an efficient therapeutic approach in the treatment of neonatal necrotizing enterocolitis.
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Affiliation(s)
- Bohuslav Dvorak
- Department of Pediatrics and Steele Memorial Children's Research Center, University of Arizona, 1501 N. Campbell Ave, P.O. Box 245073, Tucson, AZ 85724, USA.
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Chung BM, Wallace LE, Winkfein RK, O'Loughlin EV, Hardin JA, Gall DG. The effect of massive small bowel resection and oral epidermal growth factor therapy on SGLT-1 distribution in rabbit distal remnant. Pediatr Res 2004; 55:19-26. [PMID: 14561780 DOI: 10.1203/01.pdr.0000098500.94041.9b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Small bowel resection decreases brush border membrane (BBM) glucose uptake kinetics. Oral epidermal growth factor (EGF) returns net glucose transport across intact tissue to control levels despite persistence of a defect in BBM glucose uptake. The purpose of this study was to examine the effects of resection and EGF treatment on sodium-dependent glucose cotransporter 1 (SGLT-1) expression in distal remnant tissue. New Zealand White rabbits (1 kg) underwent 70% small bowel resection (R). One group of resected animals (R-EGF) received oral EGF (40 microg/kg, days 3-8). Distal remnant tissue was harvested 10 d after surgery, and compared with controls (C). Mucosal SGLT-1 mRNA was measured by Northern blot, BBM SGLT-1 content by Western blot, and villus distribution of SGLT-1 protein and mRNA by immunofluorescence and in situ hybridization. Western blot indicated BBM from both resected and EGF-treated tissue had decreased SGLT-1 content (C, 0.55 +/- 0.04; R, 0.35 +/- 0.04; R-EGF, 0.35 +/- 0.03 trace OD; n = 5; p < 0.05). Northern blot revealed no alterations in mucosal SGLT-1 mRNA content in any group. SGLT-1 protein and mRNA localization in control tissues was characterized by a gradual increase in stain intensity from the base of the villus to the villus tip. Resection altered SGLT-1 protein and mRNA expression along the villus axis with intensity being strongest in the mid-villus region and little expression at the tip of the villus. Oral EGF normalized SGLT-1 protein and mRNA expression to control patterns. Resection alters SGLT-1 protein and mRNA expression along the villus axis, despite no change in total mucosal SGLT-1 mRNA content. EGF normalized villus SGLT-1 protein and mRNA distribution, without altering overall BBM SGLT-1 content or mucosal mRNA levels.
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Affiliation(s)
- Brian M Chung
- Department of Pediatrics, Faculty of Medicine, University of Calgary, 3330 University Calgary, Alberta T2N 4N1, Canada.
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Knott AW, Erwin CR, Profitt SA, Juno RJ, Warner BW. Localization of postresection EGF receptor expression using laser capture microdissection. J Pediatr Surg 2003; 38:440-5. [PMID: 12632364 DOI: 10.1053/jpsu.2003.50076] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND/PURPOSE Epidermal growth factor (EGF) and its receptor (EGFR) are key components in the genesis of adaptation after small bowel resection (SBR). Within intestinal homogenates, EGFR expression is increased after SBR; however, the exact cells responsible for altered EGFR expression are unknown. In this study, laser capture microdissection (LCM) microscopy was used to elucidate the specific cellular compartment(s) responsible for postresection changes in EGFR expression. METHODS Male ICR mice underwent a 50% proximal SBR or sham operation. After 3 days, frozen sections were taken from the remnant ileum. Individual cells from villi, crypt, muscularis, and mesenchymal compartments were isolated by LCM. EGFR mRNA expression for each cell compartment was quantified using real-time polymerase chain reaction (PCR). RESULTS EGFR expression was increased after SBR within the crypt (2-fold) and muscularis compartments (3-fold). There were no changes detected after SBR in the villus tips or mesenchymal compartments. CONCLUSIONS Increased expression of EGFR in crypts directly correlates with the zone of cell proliferation and supports the hypothesis that EGFR signaling is crucial for the mitogenic stimulus for adaptation. The finding of increased EGFR expression in the muscular compartment is novel and may implicate a role for EGFR as a mediator of the muscular hyperplasia seen after massive SBR.
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Affiliation(s)
- Andrew W Knott
- Division of Pediatric Surgery, Cincinnati Children's Hospital Medical Center, and the Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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O'Brien DP, Nelson LA, Williams JL, Kemp CJ, Erwin CR, Warner BW. Selective inhibition of the epidermal growth factor receptor impairs intestinal adaptation after small bowel resection. J Surg Res 2002; 105:25-30. [PMID: 12069497 DOI: 10.1006/jsre.2002.6440] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Prior indirect studies have suggested that a functional epidermal growth factor receptor (EGFR) appears to be indispensable for the adaptive response of the remnant intestine to massive small bowel resection (SBR). The recent availability of a specific pharmacologic EGFR inhibitor enabled us to more directly test the hypothesis that EGFR signaling is required for postresection intestinal adaptation. METHODS Mice (C57B1/6, n = 26) underwent a 50% SBR or sham operation and were then given orogastric EGFR inhibitor (ZD1839, 50 mg/kg/day) or vehicle. After 3 days, indices of adaptation (wet weight, crypt depth, and villus height) and apoptotic index (number of apoptotic bodies per crypt) were calculated in the ileum. The expression of proliferating cell nuclear antigen (PCNA) and activated EGFR was measured by Western blotting. RESULTS ZD1839 prevented EGFR activation and the normal postresection increases in ileal wet weight, villus height, and crypt depth. Enterocyte proliferation was reduced twofold in the SBR group by ZD1839. Although not statistically significant, rates of enterocyte apoptosis were the highest in the inhibitor-treated mice. CONCLUSION Following massive SBR, pharmacologic inhibition of the EGFR attenuates proliferation and the normal adaptive response of the intestine. These results more directly confirm the requirement of a functional EGFR as a mediator of the postresection adaptation response. This study demonstrates an in vivo application of a novel selective EGFR inhibitor and offers a unique experimental model to gain mechanistic insight into understanding postresection intestinal adaptation.
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Affiliation(s)
- David P O'Brien
- Division of Pediatric Surgery, Cincinnati Children's Hospital Medical Center, Ohio 45229, USA
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Sham J, Martin G, Meddings JB, Sigalet DL. Epidermal growth factor improves nutritional outcome in a rat model of short bowel syndrome. J Pediatr Surg 2002; 37:765-9. [PMID: 11987096 DOI: 10.1053/jpsu.2002.32273] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND/PURPOSE This study investigates the effect of epidermal growth factor (EGF) on nutrient absorption in a rat model of short bowel syndrome (SBS). METHODS Male juvenile rats underwent either transection (Sham) or ileocecal resection leaving a 20-cm jejunal remnant. Animals underwent follow-up for 10 days, and resected animals were treated with placebo or recombinant human EGF (1-53). Animals were pair fed; in vivo nutrient absorption, intestinal permeability, morphology, and total intestinal DNA and protein content were measured. RESULTS Resected EGF-treated animals lost significantly less weight than those in the placebo group (-4.2 +/- 3 v -13.7 +/- 6.9%), absorbed significantly more 3-0 methylglucose (76.8 +/- 6.6 v 64.9 +/- 10.1%), and had reduced permeability (lactulose/mannitol ratio, 0.35 +/- 0.19 v 0.60 +/- 0.20; P <.05 for all comparisons). CONCLUSIONS These findings show that treatment of short bowel syndrome animals with EGF reduced weight loss and improved carbohydrate absorption and intestinal permeability. These findings suggest that enteral EGF may be a useful therapy for short bowel syndrome; further studies are indicated.
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Nelson LA, O'Brien DP, Kemp CJ, Williams JL, Dunke-Jacobs E, Erwin CR, Warner BW. Intestinal and hepatic response to combined partial hepatectomy and small bowel resection in mice. Am J Surg 2002; 183:435-40. [PMID: 11975933 DOI: 10.1016/s0002-9610(02)00809-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Both partial-hepatectomy (PHx) and massive small bowel resection (SBR) are strong mitogenic signals to the remnant liver and intestine, respectively. This study tested the hypothesis that PHx was an additive signal for intestinal adaptation after massive SBR. METHODS Male mice underwent either sham SBR or 50% proximal SBR. Mice from these two groups were then subjected to a 70% PHx or sham PHx. After 3 days, parameters of intestinal adaptation and liver regeneration were recorded in the remnant intestine and liver, respectively. RESULTS Intestinal adaptation following SBR occurred normally, but was not enhanced after concomitant PHx. On the other hand, SBR impaired the regenerative ability of the liver following PHx. CONCLUSIONS Intestinal adaptation after SBR takes priority over liver regeneration after PHx. These data implicate a hierarchy with regard to adaptive alterations to organ loss and endorse an important role for the intestinal mucosa in the regulation of hepatic regeneration.
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Affiliation(s)
- Lindsey A Nelson
- Division of Pediatric Surgery, Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA
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Wong WR, Lam E, Huang RC, Wong RS, Morris C, Hackett J. Applications, and efficient large-scale production, of recombinant human epidermal growth factor. Biotechnol Genet Eng Rev 2002; 18:51-71. [PMID: 11530698 DOI: 10.1080/02648725.2001.10648008] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- W R Wong
- Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
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41
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O'Brien DP, Nelson LA, Huang FS, Warner BW. Intestinal adaptation: structure, function, and regulation. Semin Pediatr Surg 2001; 10:56-64. [PMID: 11329606 DOI: 10.1053/spsu.2001.22383] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
After massive small bowel resection (SBR), the remnant intestine undergoes an adaptive process characterized by increases in wet weight, protein and DNA content, villus height and crypt depth, and absorptive surface area. These changes are the result of a proliferative stimulus that increases crypt cell mitosis and augments cellular progression along the villus axis. Functionally, there is upregulation of the Na(+)/glucose cotransporter, Na(+)/H(+) exchanger, and other enzymes involved in intestinal digestion and absorption. These physiologic events are a compensatory response to the sudden loss of digestive and absorptive capacity by the remnant intestine. A major consequence of inadequate intestinal adaptation is lifelong dependence on parenteral nutrition, which results ultimately in cholestatic liver dysfunction. Furthermore, adaptation may be associated with changes in intestinal permeability and an increased risk of bacterial translocation and sepsis. Several mediators thought to be integral to the postresection adaptive response have been proposed, including luminal nutrients, gastrointestinal secretions, and humoral factors. A thorough understanding of intestinal adaptation will be essential in the rational development of new and innovative therapies that amplify this complex but important process.
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Affiliation(s)
- D P O'Brien
- Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Stern LE, Erwin CR, Falcone RA, Huang FS, Kemp CJ, Williams JL, Warner BW. cDNA microarray analysis of adapting bowel after intestinal resection. J Pediatr Surg 2001; 36:190-5. [PMID: 11150463 DOI: 10.1053/jpsu.2001.20050] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND/PURPOSE Studies of the genetic regulation of various physiologic processes have been hampered by methodologies that are limited to the analysis of individual genes. The advent of cDNA microarray technology has permitted the simultaneous screening of numerous genes for alterations in expression. In this study, cDNA microarrays were used to evaluate gene expression changes during the intestinal adaptive response to massive small bowel resection (SBR). METHODS Male ICR mice (n = 20) underwent either a 50% SBR or sham operation and then were given either orogastric epidermal growth factor (EGF, 50 microg/kg/d) or saline. After 3 days, cDNA microarray analysis was performed on mRNA extracted from the remnant ileum. RESULTS From over 8,700 different genes, the array identified 27 genes that were altered 2-fold or greater after SBR. Small proline-rich protein 2 (sprr2), the gene with the greatest expression change (4.9-fold), was further upregulated by EGF. This gene has never been characterized in the intestine or described in intestinal adaptation. CONCLUSIONS cDNA microarray analysis showed enhanced expression of sprr2, a gene not previously known to be involved in the physiology of adaptation after SBR. This technology provides a more rapid and efficient means of dissecting the complex genetic regulation of gut adaptation.
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Affiliation(s)
- L E Stern
- Division of Pediatric Surgery, Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45229-3039, USA
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Stern LE, Erwin CR, O'Brien DP, Huang F, Warner BW. Epidermal growth factor is critical for intestinal adaptation following small bowel resection. Microsc Res Tech 2000. [PMID: 11054864 DOI: 10.1002/1097-0029(20001015)51:2%3c138::aid-jemt5%3e3.0.co;2-t] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The loss of small intestinal mucosal surface area is a relatively common clinical situation seen in both the pediatric and adult population. The most frequent causes include mesenteric ischemia, trauma, inflammatory bowel disease, necrotizing enterocolitis, and volvulus. Following surgical resection, the remnant intestine compensates or adapts to the loss of native bowel by increasing its absorptive surface area and functional capacity. Unfortunately, many patients fail to adapt adequately, and are relegated to lifelong intravenous nutrition. Research into intestinal adaptation following small bowel resection (SBR) has evolved only recently from the gross and microscopic level to the biochemical and genetic level. As understanding of this process has increased, numerous therapeutic strategies to augment adaptation have been proposed. Epidermal growth factor (EGF) is an endogenous peptide that is secreted into the gastrointestinal tract and able to influence gut ontogeny, as well as mucosal healing. Early studies have demonstrated its ability to augment the adaptive process. Focusing on a murine model of massive intestinal loss, the morphological, structural, biochemical, and genetic changes that occur during the intestinal adaptive process will be reviewed. The role of EGF and its receptor as critical mediators of the adaptive process will be discussed. Additionally, the ability of EGF to augment intestinal proliferation and diminish programmed cell death (apoptosis) following SBR will be examined. Enhancing adaptation in a controlled manner may allow patients to transition off parenteral nutrition to enteral feeding and, thereby, normalize their lifestyle.
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Affiliation(s)
- L E Stern
- Division of Pediatric Surgery, Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Stern LE, Erwin CR, O'Brien DP, Huang F, Warner BW. Epidermal growth factor is critical for intestinal adaptation following small bowel resection. Microsc Res Tech 2000; 51:138-48. [PMID: 11054864 DOI: 10.1002/1097-0029(20001015)51:2<138::aid-jemt5>3.0.co;2-t] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The loss of small intestinal mucosal surface area is a relatively common clinical situation seen in both the pediatric and adult population. The most frequent causes include mesenteric ischemia, trauma, inflammatory bowel disease, necrotizing enterocolitis, and volvulus. Following surgical resection, the remnant intestine compensates or adapts to the loss of native bowel by increasing its absorptive surface area and functional capacity. Unfortunately, many patients fail to adapt adequately, and are relegated to lifelong intravenous nutrition. Research into intestinal adaptation following small bowel resection (SBR) has evolved only recently from the gross and microscopic level to the biochemical and genetic level. As understanding of this process has increased, numerous therapeutic strategies to augment adaptation have been proposed. Epidermal growth factor (EGF) is an endogenous peptide that is secreted into the gastrointestinal tract and able to influence gut ontogeny, as well as mucosal healing. Early studies have demonstrated its ability to augment the adaptive process. Focusing on a murine model of massive intestinal loss, the morphological, structural, biochemical, and genetic changes that occur during the intestinal adaptive process will be reviewed. The role of EGF and its receptor as critical mediators of the adaptive process will be discussed. Additionally, the ability of EGF to augment intestinal proliferation and diminish programmed cell death (apoptosis) following SBR will be examined. Enhancing adaptation in a controlled manner may allow patients to transition off parenteral nutrition to enteral feeding and, thereby, normalize their lifestyle.
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Affiliation(s)
- L E Stern
- Division of Pediatric Surgery, Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Stern LE, Falcone RA, Kemp CJ, Braun MC, Erwin CR, Warner BW. Salivary epidermal growth factor and intestinal adaptation in male and female mice. Am J Physiol Gastrointest Liver Physiol 2000; 278:G871-7. [PMID: 10859216 DOI: 10.1152/ajpgi.2000.278.6.g871] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Salivary epidermal growth factor (sEGF) levels are increased in male mice after small bowel resection (SBR) and may be important during intestinal adaptation. Since males have greater sEGF than females, the influence of sex on postresection adaptation was tested. Females had lower sEGF; however, sEGF substantially increased in both sexes after a massive (50%) SBR. Adaptive increases in DNA and protein content, villus height, and crypt depth, as well as crypt cell proliferation rates in the remnant ileum, were not different between males and females. Although significant postresection increases in sEGF were identified, EGF mRNA and protein did not change within the submandibular gland. Glandular kallikrein-13 and ileal EGF receptor expression were greater after SBR in female mice. Intestinal adaptation is equivalent in female and male mice after SBR. Despite lower sEGF, females demonstrated increased expression of a kallikrein responsible for sEGF precursor cleavage as well as amplified ileal EGF receptor expression. These results endorse an important differential response between sexes regarding sEGF mobilization and intestinal receptor availability during adaptation.
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Affiliation(s)
- L E Stern
- Division of Pediatric Surgery, Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Stern LE, Falcone RA, Huang F, Kemp CJ, Erwin CR, Warner BW. Epidermal growth factor alters the bax:bcl-w ratio following massive small bowel resection. J Surg Res 2000; 91:38-42. [PMID: 10816347 DOI: 10.1006/jsre.2000.5897] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Following massive small bowel resection (SBR), the expression of bax and bcl-w is associated with increased enterocyte apoptosis. Epidermal growth factor (EGF) has been shown to enhance enterocyte proliferation and retard apoptosis in the adapting bowel. This study examined the effect of EGF on the expression of these bcl-2 family members during adaptation. MATERIALS AND METHODS Mice (C57Bl/6; n = 38) underwent a 50% SBR or sham operation and then were randomized to receive twice-daily orogastric saline or EGF (50 microg/kg/day). After 3 days, the remnant ileum was removed, apoptotic index (No. apoptotic bodies/crypt) calculated, and expression of mRNA and protein for bax and bcl-w quantified. RESULTS EGF prevented the expected increase in the apoptotic index after SBR and altered the ratio of bax to bcl-w in favor of cell survival. CONCLUSION Following massive small bowel resection, EGF retards rates of enterocyte apoptosis and modifies the expression of bcl-2 family members. By decreasing bax and increasing bcl-w expression, the balance between pro- and anti-apoptotic genes is shifted in favor of cell survival. Alteration of bcl-2 family member expression may be an important mechanism by which EGF reduces the increased enterocyte apoptosis that occurs after massive small bowel resection.
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Affiliation(s)
- L E Stern
- Division of Pediatric Surgery, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA
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Devine DA, High AS, Owen PJ, Poulsom R, Bonass WA. Trefoil factor expression in normal and diseased human salivary glands. Hum Pathol 2000; 31:509-15. [PMID: 10821500 DOI: 10.1053/hp.2000.6549] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Trefoil factors are wound-healing peptides important in protection and healing of the human gastrointestinal tract. Their potential for therapy of gastrointestinal ulcers has been established. This study investigated the hypothesis that trefoil factors are also present in human salivary gland. Tissues from surgical biopsy specimens were collected fresh into ice and stored in liquid nitrogen. Breast, stomach, and colon constituted positive controls. Trefoil factor mRNAs were detected by reverse transcription polymerase chain reaction (RT-PCR) or by in situ hybridization (ISH) with formalin-fixed, paraffin-embedded sections. Amplified DNA fragments were ligated into pGEM-T Easy vector and used to transform competent Escherichia coli JM109, allowing sequencing to confirm identity of cloned fragments. Generation of amplifiable cDNA was confirmed using primers specific to the ubiquitously expressed abl gene. By RT-PCR, TFF1 (pS2) mRNA was detected in 14 of 15 glands, TFF3 (hITF) mRNA in 13, and TFF2 (hSP) in only 1 gland. ISH of 15 glands (7 of which had been studied by RT-PCR) showed the same pattern of expression and indicated that TFF1 mRNA was usually expressed at low levels by a few mucous cells, whereas TFF3 was produced abundantly by most mucous cells. There was no difference in patterns of expression comparing parotid, submandibular, and minor mucous glands. Nor was there an obvious relationship between trefoil factor expression and pathology, but those glands not expressing TFF1 or TFF3 had evidence of chronic inflammation or atrophy. Trefoil factors are likely to be important in healing, predisposition to, and therapy of, oral diseases.
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Affiliation(s)
- D A Devine
- Leeds Dental Institute, University of Leeds, United Kingdom
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Falcone RA, Stern LE, Kemp CJ, Erwin CR, Warner BW. Intestinal adaptation occurs independent of transforming growth factor-alpha. J Pediatr Surg 2000; 35:365-70. [PMID: 10693698 DOI: 10.1016/s0022-3468(00)90042-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND/PURPOSE Signal transduction via the epidermal growth factor receptor (EGFR) is critical for intestinal adaptation after massive small bowel resection (SBR). Although it has been assumed that the major ligand for the EGFR during adaptation is EGF, the role for transforming growth factor-alpha (TGF-alpha), another major ligand for the EGFR is unknown. The purpose of this study was to test the hypothesis that TGF-alpha is an important ligand for the EGFR during intestinal adaptation. METHODS Wild-type mice (C57BI/6) underwent a 50% proximal SBR or sham operation (bowel transection or reanastomosis) and were then assigned randomly to receive either intraperitoneal TGF-alpha or placebo. In a separate experiment, SBR or sham operations were performed in mice lacking TGF-alpha (Waved-1). After 3 days, adaptation was measured in the ileum. RESULTS Exogenous TGF-alpha enhanced intestinal adaptation in the wild-type mice after SBR as shown by increased ileal wet weight and DNA content. Normal adaptation occurred in the mice lacking TGF-alpha as shown by increased ileal wet weight, protein and DNA content, proliferation, villus height, and crypt depth. CONCLUSIONS Although exogenous TGF-alpha enhanced adaptation after massive SBR, adaptation was preserved in TGF-alpha-absent mice. These results refute TGF-alpha as an essential ligand for EGFR signaling during intestinal adaptation.
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Affiliation(s)
- R A Falcone
- Department of Surgery, University of Cincinnati College of Medicine, OH, USA
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Shin CE, Falcone RA, Stuart L, Erwin CR, Warner BW. Diminished epidermal growth factor levels in infants with necrotizing enterocolitis. J Pediatr Surg 2000; 35:173-6; discussion 177. [PMID: 10693661 DOI: 10.1016/s0022-3468(00)90005-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND/PURPOSE Because epidermal growth factor (EGF) is trophic to the intestinal mucosa, and neonatal necrotizing enterocolitis (NEC) is associated with a disrupted intestinal mucosal barrier, the authors sought to determine whether diminished levels of EGF were present in infants with NEC. METHODS Saliva, serum, and urine specimens were obtained from infants with NEC during a 3-year period (February 1995 to May 1998). Control patients without NEC were chosen based on similar postnatal age and birthweight. EGF levels were determined by enzyme-linked immunosorbent assay (ELISA). Differences between groups were compared using Mann-Whitney Rank sum test with P less than .05 considered significant. Results are presented as mean values +/-SEM. RESULTS Twenty-five infants with NEC were compared with 19 control patients. Birth weight (1,616+/-238 g control v. 1,271+/-124 g NEC) and postnatal age (23+/-6 days control v. 22+/-3 days NEC) were similar. Infants with NEC had significantly lower levels of EGF in both saliva (590+/-80 pg/mL control v. 239+/-41 pg/mL NEC; P<.001) and serum (35+/-8 pg/mL control v. 5.6+/-1.9 pg/mL NEC; P<.001). Urinary EGF was also lower in the NEC group, but was not statistically significant. CONCLUSIONS Premature infants with NEC have significantly diminished levels of salivary and serum EGF. Reduced levels of this growth factor may distinguish infants at risk for NEC and play a pivotal role in the pathogenesis of the perturbed intestinal mucosal barrier that is central to this condition.
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Affiliation(s)
- C E Shin
- Department of Surgery, Children's Hospital Medical Center, University of Cincinnati College of Medicine, OH 45229-3039, USA
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Falcone RA, Shin CE, Stern LE, Wang Z, Erwin CR, Soleimani M, Warner BW. Differential expression of ileal Na(+)/H(+) exchanger isoforms after enterectomy. J Surg Res 1999; 86:192-7. [PMID: 10534423 DOI: 10.1006/jsre.1999.5720] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Na(+)/H(+) exchangers (NHE) are transporters involved in the absorption of NaCl along the gastrointestinal tract. The aim of this study was to determine the expression pattern of the intestinal brush border NHE isoforms 2 and 3 following massive small bowel resection (SBR). Additionally, the effect of epidermal growth factor (EGF) and salivarectomy (removal of the primary source of EGF) on the expression pattern was studied. MATERIALS AND METHODS ICR mice underwent a proximal SBR or sham surgery and then received either orogastric saline or EGF (50 microg/kg/day). In separate experiments mice underwent salivarectomy followed by SBR or sham. Postoperatively the remaining ileum was isolated and levels of NHE-2 and NHE-3 mRNA and protein were resolved. RESULTS Following SBR, the expression of both mRNA and protein for NHE-3 increased by approximately 2.5-fold. Treatment with EGF enhanced NHE-3 mRNA in sham animals with further elevation following SBR. The expression of NHE-2 mRNA demonstrated minimal change while protein marginally increased (40%) following SBR. EGF did not affect the expression of NHE-2 mRNA. Salivarectomy did not influence NHE-2 protein expression and inhibited the increased NHE-3 protein expression following SBR. CONCLUSIONS Following SBR, the expression pattern for brush border NHE isoforms is distinctive. Increased expression of NHE-3 secondary to SBR and/or EGF treatment with loss of this increase following salivarectomy implies a common mechanism to enhance enterocyte proliferation and luminal absorption of NaCl and water. These results suggest that NHE-3 is an important ileal exchanger following SBR.
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Affiliation(s)
- R A Falcone
- Department of Surgery, Children's Hospital Medical Center, Cincinnati, Ohio, 45229, USA
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