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Zhang Y, Yan M, Xia Y, Yue Y, Wang S, Hu Y, Lai G, Wu Q, Liu Q, Ding X, Guo C. Glutaredoxin-1 modulates the NF-κB signaling pathway to activate inducible nitric oxide synthase in experimental necrotizing enterocolitis. Mol Ther Methods Clin Dev 2024; 32:101214. [PMID: 38496303 PMCID: PMC10940916 DOI: 10.1016/j.omtm.2024.101214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 02/16/2024] [Indexed: 03/19/2024]
Abstract
Inducible nitric oxide synthase (iNOS), regulated by nuclear factor kappa B (NF-κB), is crucial for intestinal inflammation and barrier injury in the progression of necrotizing enterocolitis (NEC). The NF-κB pathway is inhibited by S-glutathionylation of inhibitory κB kinase β (IKKβ), which can be restored by glutaredoxin-1 (Grx1). Thus, we aim to explore the role of Grx1 in experimental NEC. Wild-type (WT) and Grx1-knockout (Grx1-/-) mice were treated with an NEC-inducing regimen. Primary intestinal epithelial cells (IECs) were subjected to LPS treatment. The production of iNOS, NO, and inflammation injuries were assessed. NF-κB and involved signaling pathways were also explored. The severity of NEC was attenuated in Grx1-/- mice. Grx1 ablation promoted IKKβ glutathionylation, NF-κB inactivation, and decreased iNOS, NO, and O2·- production in NEC mice. Furthermore, Grx1 ablation restrained proinflammatory cytokines and cell apoptosis, ameliorated intestinal barrier damage, and promoted proliferation in NEC mice. Grx1 ablation protected NEC through iNOS and NO inhibition, which related to S-glutathionylation of IKKβ to inhibit NF-κB signaling. Grx1-related signaling pathways provide a new therapeutic target for NEC.
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Affiliation(s)
- Yunfei Zhang
- Pediatric Center of the First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China
- Department of Gastrointestinal Surgery, Renshou People’s Hospital, Meishan, Sichuan, P.R. China
| | - Mei Yan
- Pediatric Center of the First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China
| | - Yingying Xia
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
- Department of Psychiatry, Xinjin District Second People’s Hospital, Chengdu, Sichuan, P.R. China
| | - Yingbin Yue
- Pediatric Center of the First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China
| | - Shuli Wang
- Department of Gastrointestinal Surgery, Renshou People’s Hospital, Meishan, Sichuan, P.R. China
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
| | - Yuhui Hu
- Department of Gastrointestinal Surgery, Renshou People’s Hospital, Meishan, Sichuan, P.R. China
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
| | - Genjian Lai
- Department of Gastrointestinal Surgery, Renshou People’s Hospital, Meishan, Sichuan, P.R. China
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
| | - Quanjiang Wu
- Department of Gastrointestinal Surgery, Renshou People’s Hospital, Meishan, Sichuan, P.R. China
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
| | - Qianyang Liu
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
- Ministry of Education Key Laboratory of Child Development and Disorders, Children’s Hospital of Chongqing Medical University, Chongqing, P.R. China
- Department of Pediatric Surgery, Chongqing Health Center for Women and Children, Chongqing, China
| | - Xin Ding
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
- Ministry of Education Key Laboratory of Child Development and Disorders, Children’s Hospital of Chongqing Medical University, Chongqing, P.R. China
- Department of Pediatric Surgery, Chongqing Health Center for Women and Children, Chongqing, China
| | - Chunbao Guo
- Department of Pediatric Surgery, Women and Children’s Hospital, Chongqing Medical University, Chongqing, P.R. China
- Ministry of Education Key Laboratory of Child Development and Disorders, Children’s Hospital of Chongqing Medical University, Chongqing, P.R. China
- Department of Pediatric Surgery, Chongqing Health Center for Women and Children, Chongqing, China
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Omar M, Abdelal HO. Nitric oxide in parasitic infections: a friend or foe? J Parasit Dis 2022; 46:1147-1163. [PMID: 36457767 PMCID: PMC9606182 DOI: 10.1007/s12639-022-01518-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/20/2022] [Indexed: 11/28/2022] Open
Abstract
The complex interaction between the host and the parasite remains a puzzling question. Control of parasitic infections requires an efficient immune response that must be balanced against destructive pathological consequences. Nitric oxide is a nitrogenous free radical which has many molecular targets and serves diverse functions. Apart from being a signaling messenger, nitric oxide is critical for controlling numerous infections. There is still controversy surrounding the exact role of nitric oxide in the immune response against different parasitic species. It proved protective against intracellular protozoa, as well as extracellular helminths. At the same time, it plays a pivotal role in stimulating detrimental pathological changes in the infected hosts. Several reports have discussed the anti-parasitic and immunoregulatory functions of nitric oxide, which could directly influence the control of the infection. Nevertheless, there is scarce literature addressing the harmful cytotoxic impacts of this mediator. Thus, this review provides insights into the most updated concepts and controversies regarding the dual nature and opposing sides of nitric oxide during the course of different parasitic infections.
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Affiliation(s)
- Marwa Omar
- Department of Medical Parasitology, Faculty of Medicine, Zagazig University, Gameyet Almohafza St. 1, Menya Al-Kamh, City of Zagazig, 44511 Sharkia Governorate Egypt
| | - Heba O. Abdelal
- LIS: Cross-National Data Center, Maison des Sciences Humaines - 5e étage, 11- porte des Sciences, L-4366 Esch-Belval, Luxembourg
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3
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Sun M, Ma N, Liu H, Liu Y, Zhou Y, Zhao J, Wang X, Li H, Ma B, Jiao H, Lin H. The optimal dietary arginine level of laying hens fed with low-protein diets. J Anim Sci Biotechnol 2022; 13:63. [PMID: 35715827 PMCID: PMC9206374 DOI: 10.1186/s40104-022-00719-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/13/2022] [Indexed: 11/10/2022] Open
Abstract
Background Arginine (Arg) is an essential amino acid (EAA) in poultry, an important substrate for protein synthesis and a precursor of several molecules. Supplementation of EAAs with low protein (LP) diet increases the utilization efficiency of dietary crude protein (CP). However, if the EAA requirement is changed in hens fed a LP diet remains to be elucidated. The aim of the present study was to evaluate the optimal level of dietary Arg in the LP diet of hens. A total of 1350 Hy-Line Brown laying hens were randomly allocated to six dietary treatments: a basal diet (16% CP, positive control), or an isoenergetic LP diet (14% CP, 0.80% Arg) supplemented 0, 0.05%, 0.10%, 0.15%, and 0.20% L-Arg, corresponding to 0.80%, 0.85%, 0.90%, 0.95% and 1.00% dietary Arg, respectively. Results The feed efficiency was decreased (P < 0.05) by 0.80% and 1.00% Arg-LP diets, compared to control. Within LP diets, dietary Arg level had significant quadratic effects (P < 0.05) on laying rate, egg mass, and feed efficiency. Compared to control, the plasma CAT activity or T-AOC content were decreased by 0.80% (P < 0.001). However, the hens offered 0.85% and 0.90% Arg-LP diets had higher CAT activity (P < 0.001) than 0.80% Arg-LP diet. In contrast, 1.00% Arg-LP group had the highest MDA and the lowest T-AOC content in plasma, liver, duodenal and jejunal mucosa (P < 0.05). Compared to control, the villus height was decreased by 0.80%, 0.95% and 1.00% Arg-LP diets, while the villus height to crypt depth (V/C) ratio was reduced by 0.95% and 1.00% Arg-LP diets in duodenum. Conclusion The result demonstrates that LP diet (14% CP) deficient in Arg (0.80% Arg) result in augmented oxidative damage and impaired development of intestinal mucosa. According to the quadratic broken-line regression model, the optimal dietary arginine levels for Hy-Line Brown laying hens fed with low protein diet (14% CP) aged 33 to 40 weeks are 0.85%, 0.86%, and 0.86% to obtained the maximum laying rate, egg mass, and feed efficiency, respectively. Supplementary Information The online version contains supplementary material available at 10.1186/s40104-022-00719-x.
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Affiliation(s)
- Mingfa Sun
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Ning Ma
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Hui Liu
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Yu Liu
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Yunlei Zhou
- College of Chemistry and Material Science, Shandong Agricultural University, Taian City, 271018, Shandong Province, China
| | - Jingpeng Zhao
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Xiaojuan Wang
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China
| | - Haifang Li
- College of Life Sciences, Shandong Agricultural University, Taian City, 271018, Shandong Province, China
| | - Baishun Ma
- Shandong He-Mei-Hua Agricultural Technology Co., Ltd, Jinan City, 250101, Shandong Province, China
| | - Hongchao Jiao
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China.
| | - Hai Lin
- Department of Animal Science, Shandong Agricultural University, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Taian City, 271018, Shandong Province, China.
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Effect of dietary cellulose supplementation on gut barrier function and apoptosis in a murine model of endotoxemia. PLoS One 2019; 14:e0224838. [PMID: 31790417 PMCID: PMC6886840 DOI: 10.1371/journal.pone.0224838] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
The gut plays a vital role in critical illness, and alterations in the gut structure and function have been reported in endotoxemia and sepsis models. Previously, we have demonstrated a novel link between the diet-induced alteration of the gut microbiome with cellulose and improved outcomes in sepsis. As compared to mice receiving basal fiber (BF) diet, mice that were fed a non-fermentable high fiber (HF) diet demonstrated significant improvement in survival and decreased organ injury in both cecal-ligation and puncture (CLP) and endotoxin sepsis models. To understand if the benefit conferred by HF diet extends to the gut structure and function, we hypothesized that HF diet would be associated with a reduction in sepsis-induced gut epithelial loss and permeability in mice. We demonstrate that the use of dietary cellulose decreased LPS-mediated intestinal hyperpermeability and protected the gut from apoptosis. Furthermore, we noted a significant increase in epithelial cell proliferation, as evidenced by an increase in the percentage of bromodeoxyuridine-positive cells in HF fed mice as compared to BF fed mice. Thus, the use of HF diet is a simple and effective tool that confers benefit in a murine model of sepsis, and understanding the intricate relationship between the epithelial barrier, gut microbiota, and diet will open-up additional therapeutic avenues for the treatment of gut dysfunction in critical illness.
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Nakamura H, O'Donnell AM, Tomuschat C, Coyle D, Puri P. Altered expression of caveolin-1 in the colon of patients with Hirschsprung's disease. Pediatr Surg Int 2019; 35:929-934. [PMID: 31256294 DOI: 10.1007/s00383-019-04505-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/20/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND/PURPOSE The pathogenesis of Hirschsprung's disease-associated enterocolitis (HAEC) is unclear. Caveolin-1 (Cav-1) regulates the functions of different nitric oxide synthase (NOS) isoforms, which play critical roles in inflammation and intestinal epithelial barrier function. We designed this study to investigate the hypothesis that Cav-1 expression is altered in the bowel of patients with Hirschsprung's disease (HSCR). METHODS HSCR tissue specimens (n = 10) were collected at the time of pull-through surgery and control samples were obtained at the time of colostomy closure in patients with imperforate anus (n = 10). qRT-PCR analysis was undertaken to quantify Cav-1 gene expression, and Western blot analysis was undertaken to determine Cav-1 protein quantification. Immunolabelling of Cav-1 proteins was visualized using confocal microscopy. RESULTS qRT-PCR and Western blot analysis revealed that Cav-1 was significantly downregulated in the aganglionic and ganglionic colon of patients with HSCR compared to controls (p < 0.01). Confocal microscopy revealed a markedly decreased expression of Cav-1 in colonic epithelium of aganglionic and ganglionic bowel of patients with HSCR compared to controls. CONCLUSION To our knowledge, this is the first report of significantly decreased Cav-1 expression in patients with HSCR. Decreased expression of Cav-1 in the bowel of HSCR may increase susceptibility to HAEC in HSCR.
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Affiliation(s)
- Hiroki Nakamura
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
| | - Anne Marie O'Donnell
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
| | - Christian Tomuschat
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
| | - David Coyle
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
| | - Prem Puri
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland. .,School of Medicine and Medical Science and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, Ireland.
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6
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The Food Contaminants Nivalenol and Deoxynivalenol Induce Inflammation in Intestinal Epithelial Cells by Regulating Reactive Oxygen Species Release. Nutrients 2017; 9:nu9121343. [PMID: 29232919 PMCID: PMC5748793 DOI: 10.3390/nu9121343] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/05/2017] [Accepted: 12/07/2017] [Indexed: 12/13/2022] Open
Abstract
Fusarium mycotoxins are fungal metabolites whose ability to affect cereal grains as multi-contaminants is progressively increasing. The trichothecene mycotoxins nivalenol (NIV) and deoxynivalenol (DON) are often found in almost all agricultural commodities worldwide. They are able to affect animal and human health, including at the intestinal level. In this study, NIV, both alone and in combination with DON, induced inflammation and increased the inflammatory response induced by lipopolysaccharide (LPS) plus Interferon-γ (IFN) in the non-tumorigenic intestinal epithelial cell line (IEC-6). The inflammatory response induced by NIV and DON involves tumor necrosis factor-α (TNF-α) production, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, nitrotyrosine formation, reactive oxygen species (ROS) release, Nuclear Factor-κB (NF-κB), Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and inflammasome activation. The pro-inflammatory effect was strongly induced by NIV and by the mycotoxin mixture, when compared to DON alone. Mechanistic studies indicate a pivotal role for ROS in the observed pro-inflammatory effects induced by mycotoxins. In this study, the interactions between NIV and DON point out the importance of their food co-contamination, further highlighting the risk assessment process that is of growing concern.
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7
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Allain T, Amat CB, Motta JP, Manko A, Buret AG. Interactions of Giardia sp. with the intestinal barrier: Epithelium, mucus, and microbiota. Tissue Barriers 2017; 5:e1274354. [PMID: 28452685 DOI: 10.1080/21688370.2016.1274354] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Understanding how intestinal enteropathogens cause acute and chronic alterations has direct animal and human health perspectives. Significant advances have been made on this field by studies focusing on the dynamic crosstalk between the intestinal protozoan parasite model Giardia duodenalis and the host intestinal mucosa. The concept of intestinal barrier function is of the highest importance in the context of many gastrointestinal diseases such as infectious enteritis, inflammatory bowel disease, and post-infectious gastrointestinal disorders. This crucial function relies on 3 biotic and abiotic components, first the commensal microbiota organized as a biofilm, then an overlaying mucus layer, and finally the tightly structured intestinal epithelium. Herein we review multiple strategies used by Giardia parasite to circumvent these 3 components. We will summarize what is known and discuss preliminary observations suggesting how such enteropathogen directly and/ or indirectly impairs commensal microbiota biofilm architecture, disrupts mucus layer and damages host epithelium physiology and survival.
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Affiliation(s)
- Thibault Allain
- a Department of Biological Sciences , University of Calgary , Calgary , AB , Canada.,b Inflammation Research Network, University of Calgary , Calgary , AB , Canada.,c Host-Parasite Interactions, University of Calgary , Calgary , AB , Canada
| | - Christina B Amat
- a Department of Biological Sciences , University of Calgary , Calgary , AB , Canada.,b Inflammation Research Network, University of Calgary , Calgary , AB , Canada.,c Host-Parasite Interactions, University of Calgary , Calgary , AB , Canada
| | - Jean-Paul Motta
- a Department of Biological Sciences , University of Calgary , Calgary , AB , Canada.,b Inflammation Research Network, University of Calgary , Calgary , AB , Canada.,c Host-Parasite Interactions, University of Calgary , Calgary , AB , Canada
| | - Anna Manko
- a Department of Biological Sciences , University of Calgary , Calgary , AB , Canada.,b Inflammation Research Network, University of Calgary , Calgary , AB , Canada.,c Host-Parasite Interactions, University of Calgary , Calgary , AB , Canada
| | - André G Buret
- a Department of Biological Sciences , University of Calgary , Calgary , AB , Canada.,b Inflammation Research Network, University of Calgary , Calgary , AB , Canada.,c Host-Parasite Interactions, University of Calgary , Calgary , AB , Canada
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Natarajan K, Abraham P. Methotrexate administration induces differential and selective protein tyrosine nitration and cysteine nitrosylation in the subcellular organelles of the small intestinal mucosa of rats. Chem Biol Interact 2016; 251:45-59. [DOI: 10.1016/j.cbi.2016.03.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 03/11/2016] [Accepted: 03/29/2016] [Indexed: 12/26/2022]
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9
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Grishin A, Bowling J, Bell B, Wang J, Ford HR. Roles of nitric oxide and intestinal microbiota in the pathogenesis of necrotizing enterocolitis. J Pediatr Surg 2016; 51:13-7. [PMID: 26577908 PMCID: PMC4894644 DOI: 10.1016/j.jpedsurg.2015.10.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 10/06/2015] [Indexed: 12/12/2022]
Abstract
Necrotizing enterocolitis remains one of the most vexing problems in the neonatal intensive care unit. Risk factors for NEC include prematurity, formula feeding, and inappropriate microbial colonization of the GI tract. The pathogenesis of NEC is believed to involve weakening of the intestinal barrier by perinatal insults, translocation of luminal bacteria across the weakened barrier, an exuberant inflammatory response, and exacerbation of the barrier damage by inflammatory factors, leading to a vicious cycle of inflammation-inflicted epithelial damage. Nitric oxide (NO), produced by inducible NO synthase (iNOS) and reactive NO oxidation intermediates play a prominent role in the intestinal barrier damage by inducing enterocyte apoptosis and inhibiting the epithelial restitution processes, namely enterocyte proliferation and migration. The factors that govern iNOS upregulation in the intestine are not well understood, which hampers efforts in developing NO/iNOS-targeted therapies. Similarly, efforts to identify bacteria or bacterial colonization patterns associated with NEC have met with limited success, because the same bacterial species can be found in NEC and in non-NEC subjects. However, microbiome studies have identified the three important characteristics of early bacterial populations of the GI tract: high diversity, low complexity, and fluidity. Whether NEC is caused by specific bacteria remains a matter of debate, but data from hospital outbreaks of NEC strongly argue in favor of the infectious nature of this disease. Studies in Cronobacter muytjensii have established that the ability to induce NEC is the property of specific strains rather than the species as a whole. Progress in our understanding of the roles of bacteria in NEC will require microbiological experiments and genome-wide analysis of virulence factors.
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Affiliation(s)
- Anatoly Grishin
- Division of Pediatric Surgery, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027; Department of Surgery, Keck School of Medicine of the University of Southern California, 4650 Sunset Boulevard, Los Angeles, CA 90027.
| | - Jordan Bowling
- Department of Surgery, Keck School of Medicine of the University of Southern California, 4650 Sunset Boulevard, Los Angeles, CA 90027.
| | - Brandon Bell
- Division of Pediatric Surgery, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027.
| | - Jin Wang
- Division of Pediatric Surgery, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027.
| | - Henri R. Ford
- Division of Pediatric Surgery, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027,Department of Surgery, Keck School of Medicine of the University of Southern California, 4650 Sunset Boulevard, Los Angeles, CA 90027
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10
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Nivalenol induces oxidative stress and increases deoxynivalenol pro-oxidant effect in intestinal epithelial cells. Toxicol Appl Pharmacol 2015; 285:118-27. [DOI: 10.1016/j.taap.2015.04.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 04/02/2015] [Accepted: 04/03/2015] [Indexed: 01/05/2023]
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11
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Liu H, Liu Z, Zhao S, Sun C, Yang M. Effect of BML-111 on the intestinal mucosal barrier in sepsis and its mechanism of action. Mol Med Rep 2015; 12:3101-6. [PMID: 25955406 DOI: 10.3892/mmr.2015.3746] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 03/26/2015] [Indexed: 11/06/2022] Open
Abstract
5(S),6(R)-7-trihydroxymethyl heptanoate (BML-111) is an lipoxin A4 receptor agonist, which modulates the immune response and attenuates hemorrhagic shock-induced acute lung injury. However, the role of BML-111 in sepsis and in the intestinal mucosal barrier are not well understood. Therefore, the present study was designed to investigate the effect of BML-111 on the intestinal mucosal barrier in a rat model of sepsis. Furthermore, the molecular mechanism of action of BML-111 was evaluated. The cecal ligation and puncture-induced rat model of sepsis was constructed, and BML-111 was administered at three different doses. The results revealed that BML-111 suppressed the elevation of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-6, while enhancing the elevation of the anti-inflammatory cytokine transforming growth factor-β in the intestine. In addition, BML-111 significantly upregulated rat defensin-5 mRNA expression levels and downregulated the induction of cell apoptosis as well as caspase-3 activity in the intestine. All these results demonstrated that BML-111 exerted protective effects on the intestinal mucosal barrier in sepsis. Further, it was indicated that alterations in the expression of toll-like receptor (TLR)2 and TLR4 may be one of the molecular mechanisms underlying the protective effect of BML-111. The present study therefore suggested that BML-111 may be a novel therapeutic agent for sepsis.
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Affiliation(s)
- Huaizheng Liu
- Emergency and Intensive Care Center, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410013, P.R. China
| | - Zuoliang Liu
- Emergency and Intensive Care Center, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410013, P.R. China
| | - Shangping Zhao
- Emergency and Intensive Care Center, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410013, P.R. China
| | - Chuanzheng Sun
- Emergency and Intensive Care Center, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410013, P.R. China
| | - Mingshi Yang
- Emergency and Intensive Care Center, The Third Xiangya Hospital of Central South University, Changsha, Hunan 410013, P.R. China
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Hunter CJ, De Plaen IG. Inflammatory signaling in NEC: Role of NF-κB, cytokines and other inflammatory mediators. ACTA ACUST UNITED AC 2013; 21:55-65. [PMID: 24388163 DOI: 10.1016/j.pathophys.2013.11.010] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Catherine J Hunter
- Department of Surgery, Division of Pediatric Surgery, Northwestern University Feinberg School of Medicine, Ann and Robert H. Lurie Children's Hospital of Chicago, United States
| | - Isabelle G De Plaen
- Department of Pediatrics, Division of Neonatology, Northwestern University Feinberg School of Medicine, Ann and Robert H. Lurie Children's Hospital of Chicago, 225 E Chicago Avenue, Box 45, Chicago, IL 60611, United States.
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13
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Chronic alcohol ingestion increases mortality and organ injury in a murine model of septic peritonitis. PLoS One 2013; 8:e62792. [PMID: 23717394 PMCID: PMC3661585 DOI: 10.1371/journal.pone.0062792] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 03/25/2013] [Indexed: 12/13/2022] Open
Abstract
Background Patients admitted to the intensive care unit with alcohol use disorders have increased morbidity and mortality. The purpose of this study was to determine how chronic alcohol ingestion alters the host response to sepsis in mice. Methods Mice were randomized to receive either alcohol or water for 12 weeks and then subjected to cecal ligation and puncture. Mice were sacrificed 24 hours post-operatively or followed seven days for survival. Results Septic alcohol-fed mice had a significantly higher mortality than septic water-fed mice (74% vs. 41%, p = 0.01). This was associated with worsened gut integrity in alcohol-fed mice with elevated intestinal epithelial apoptosis, decreased crypt proliferation and shortened villus length. Further, alcohol-fed mice had higher intestinal permeability with decreased ZO-1 and occludin protein expression in the intestinal tight junction. The frequency of splenic and bone marrow CD4+ T cells was similar between groups; however, splenic CD4+ T cells in septic alcohol-fed mice had a marked increase in both TNF and IFN-γ production following ex vivo stimulation. Neither the frequency nor function of CD8+ T cells differed between alcohol-fed and water-fed septic mice. NK cells were decreased in both the spleen and bone marrow of alcohol-fed septic mice. Pulmonary myeloperoxidase levels and BAL levels of G-CSF and TFG-β were higher in alcohol-fed mice. Pancreatic metabolomics demonstrated increased acetate, adenosine, xanthine, acetoacetate, 3-hydroxybutyrate and betaine in alcohol-fed mice and decreased cytidine, uracil, fumarate, creatine phosphate, creatine, and choline. Serum and peritoneal cytokines were generally similar between alcohol-fed and water-fed mice, and there were no differences in bacteremia, lung wet to dry weight, or pulmonary, liver or splenic histology. Conclusions When subjected to the same septic insult, mice with chronic alcohol ingestion have increased mortality. Alterations in intestinal integrity, the host immune response, and pancreatic metabolomics may help explain this differential response.
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Abstract
The pathogenesis of necrotizing enterocolitis (NEC) is complex and its speed of progression is variable. To gain understanding of the disease, researchers have examined tissues resected from patients with NEC; however, as these are obtained at late stages of the disease, they do not yield clues about the early pathogenic events leading to NEC. Therefore, animal models are used and have helped identify a role for several mediators of the inflammatory network in NEC. In this article, we discuss the evidence for the role of these inflammatory mediators and conclude with a current unifying hypothesis regarding NEC pathogenesis.
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Affiliation(s)
- Isabelle G. De Plaen
- Associate Professor of Pediatrics, Department of Pediatrics, Division of Neonatology, Northwestern University Feinberg School of Medicine, Children’s Hospital of Chicago Research Center, Ann and Robert H. Lurie Children’s Hospital of Chicago, 225 E. Chicago Ave, Box 45, Chicago, IL 60611-2605, U.S.A., Tel: (773)-755-6379; fax: (312)-227-9758
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Zou C, Chen Y, Smith RM, Snavely C, Li J, Coon TA, Chen BB, Zhao Y, Mallampalli RK. SCF(Fbxw15) mediates histone acetyltransferase binding to origin recognition complex (HBO1) ubiquitin-proteasomal degradation to regulate cell proliferation. J Biol Chem 2013; 288:6306-16. [PMID: 23319590 DOI: 10.1074/jbc.m112.426882] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Histone acetyltransferase binding to origin recognition complex (HBO1) plays a crucial role in DNA replication licensing and cell proliferation, yet its molecular regulation in cells is relatively unknown. Here an uncharacterized protein, Fbxw15, directly interacts with HBO1, a labile protein (t½ = ∼3 h), to mediate its ubiquitination (Lys(338)) and degradation in the cytoplasm. Fbxw15-mediated HBO1 depletion required mitogen-activated protein kinase 1 (Mek1), which was sufficient to trigger HBO1 phosphorylation and degradation in cells. Mek1 ability to produce HBO1 degradation was blocked by Fbxw15 silencing. Lipopolysaccharide induced HBO1 degradation, an effect abrogated by Fbxw15 or Mek1 cellular depletion. Modulation of Fbxw15 levels was able to differentially regulate histone H3K14 acetylation and cellular proliferation by altering HBO1 levels. These studies authenticate Fbxw15 as a ubiquitin E3 ligase subunit that mediates endotoxin-induced HBO1 depletion in cells, thereby controlling cell replicative capacity.
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Affiliation(s)
- Chunbin Zou
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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16
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Buret AG, Bhargava A. Modulatory mechanisms of enterocyte apoptosis by viral, bacterial and parasitic pathogens. Crit Rev Microbiol 2013; 40:1-17. [DOI: 10.3109/1040841x.2012.746952] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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18
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Seimetz M, Parajuli N, Pichl A, Veit F, Kwapiszewska G, Weisel FC, Milger K, Egemnazarov B, Turowska A, Fuchs B, Nikam S, Roth M, Sydykov A, Medebach T, Klepetko W, Jaksch P, Dumitrascu R, Garn H, Voswinckel R, Kostin S, Seeger W, Schermuly RT, Grimminger F, Ghofrani HA, Weissmann N. Inducible NOS inhibition reverses tobacco-smoke-induced emphysema and pulmonary hypertension in mice. Cell 2011; 147:293-305. [PMID: 22000010 DOI: 10.1016/j.cell.2011.08.035] [Citation(s) in RCA: 250] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 04/30/2011] [Accepted: 08/13/2011] [Indexed: 12/12/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is one of the most common causes of death worldwide. We report in an emphysema model of mice chronically exposed to tobacco smoke that pulmonary vascular dysfunction, vascular remodeling, and pulmonary hypertension (PH) precede development of alveolar destruction. We provide evidence for a causative role of inducible nitric oxide synthase (iNOS) and peroxynitrite in this context. Mice lacking iNOS were protected against emphysema and PH. Treatment of wild-type mice with the iNOS inhibitor N(6)-(1-iminoethyl)-L-lysine (L-NIL) prevented structural and functional alterations of both the lung vasculature and alveoli and also reversed established disease. In chimeric mice lacking iNOS in bone marrow (BM)-derived cells, PH was dependent on iNOS from BM-derived cells, whereas emphysema development was dependent on iNOS from non-BM-derived cells. Similar regulatory and structural alterations as seen in mouse lungs were found in lung tissue from humans with end-stage COPD.
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Affiliation(s)
- Michael Seimetz
- University of Giessen Lung Center, Excellence Cluster Cardiopulmonary System, Giessen, Germany
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19
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Zahiri HR, Perrone EE, Strauch ED. Bile salt supplementation acts via the farnesoid X receptor to alleviate lipopolysaccharide-induced intestinal injury. Surgery 2011; 150:480-9. [DOI: 10.1016/j.surg.2011.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 07/06/2011] [Indexed: 01/16/2023]
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20
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Leitão RF, Brito GA, Oriá RB, Braga-Neto MB, Bellaguarda EA, Silva JV, Gomes AS, Lima-Júnior RC, Siqueira FJ, Freire RS, Vale ML, Ribeiro RA. Role of inducible nitric oxide synthase pathway on methotrexate-induced intestinal mucositis in rodents. BMC Gastroenterol 2011; 11:90. [PMID: 21846355 PMCID: PMC3170268 DOI: 10.1186/1471-230x-11-90] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 08/16/2011] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Methotrexate treatment has been associated to intestinal epithelial damage. Studies have suggested an important role of nitric oxide in such injury. The aim of this study was to investigate the role of nitric oxide (NO), specifically iNOS on the pathogenesis of methotrexate (MTX)-induced intestinal mucositis. METHODS Intestinal mucositis was carried out by three subcutaneous MTX injections (2.5 mg/kg) in Wistar rats and in inducible nitric oxide synthase knock-out (iNOS-/-) and wild-type (iNOS+/+) mice. Rats were treated intraperitoneally with the NOS inhibitors aminoguanidine (AG; 10 mg/Kg) or L-NAME (20 mg/Kg), one hour before MTX injection and daily until sacrifice, on the fifth day. The jejunum was harvested to investigate the expression of Ki67, iNOS and nitrotyrosine by immunohistochemistry and cell death by TUNEL. The neutrophil activity by myeloperoxidase (MPO) assay was performed in the three small intestine segments. RESULTS AG and L-NAME significantly reduced villus and crypt damages, inflammatory alterations, cell death, MPO activity, and nitrotyrosine immunostaining due to MTX challenge. The treatment with AG, but not L-NAME, prevented the inhibitory effect of MTX on cell proliferation. MTX induced increased expression of iNOS detected by immunohistochemistry. MTX did not cause significant inflammation in the iNOS-/- mice. CONCLUSION These results suggest an important role of NO, via activation of iNOS, in the pathogenesis of intestinal mucositis.
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Affiliation(s)
- Renata Fc Leitão
- Department of Morphology, Federal University of Ceará, Fortaleza, Brazil
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21
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Cotton JA, Beatty JK, Buret AG. Host parasite interactions and pathophysiology in Giardia infections. Int J Parasitol 2011; 41:925-33. [PMID: 21683702 DOI: 10.1016/j.ijpara.2011.05.002] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 05/13/2011] [Accepted: 05/14/2011] [Indexed: 12/13/2022]
Abstract
Giardia is a protozoan parasite of the small intestine, and a leading cause of diarrhoeal disease worldwide in a variety of animals, including humans. The host-parasite interaction and pathophysiological processes of giardiasis remain incompletely understood. Current research suggests that Giardia-induced diarrhoeal disease is mediated by small intestinal malabsorption and maldigestion, chloride hypersecretion and increased rates of small intestinal transit. Small intestinal malabsorption and maldigestion results from the CD8+ lymphocyte-induced diffuse shortening of brush border microvilli. Activation of CD8+ lymphocytes occurs secondary to small intestinal barrier dysfunction, which results from heightened rates of enterocyte apoptosis and disruption of epithelial tight junctions. Both host and parasite factors contribute to the pathogenesis of giardiasis and ongoing research in this field may elucidate genotype/assemblage-specific pathogenic mechanisms. Giardia infections can result in chronic gastrointestinal disorders such as post-infectious Irritable Bowel Syndrome and symptoms may manifest at extra-intestinal sites, even though the parasite does not disseminate beyond the gastrointestinal tract. The infection can cause failure to thrive in children. Furthermore, there is now evidence suggesting that Giardia symptoms may vary between industrialised and developing areas of the world, for reasons that remain obscure. More research is needed to improve our understanding of this parasitic infection which was recently included in the World Health Organisation "Neglected Disease Initiative".
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Affiliation(s)
- James A Cotton
- Dept. of Biological Sciences, Inflammation Research Network, University of Calgary, Calgary (AB), Canada T2N 1N4
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Perrone EE, Chen C, Longshore SW, Okezie O, Warner BW, Sun CC, Alaish SM, Strauch ED. Dietary bile acid supplementation improves intestinal integrity and survival in a murine model. J Pediatr Surg 2010; 45:1256-65. [PMID: 20620329 PMCID: PMC2904360 DOI: 10.1016/j.jpedsurg.2010.02.094] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 02/23/2010] [Indexed: 11/30/2022]
Abstract
PURPOSE In vitro supplementation of the bile salt, taurodeoxycholic acid (TDCA), has been shown to stimulate proliferation and prevent intestinal apoptosis in IEC-6 cells. We hypothesize that addition of TDCA to a rodent liquid diet will be protective against induced intestinal injury. METHODS C57Bl6 mice were fed a liquid diet with or without 50-mg/(kg d) TDCA supplementation. After 6 days, the mice were injected with lipopolysaccharide (LPS) (10 mg/kg) to induce intestinal injury. Specimens were obtained 24 hours later and evaluated for intestinal apoptosis, crypt proliferation, and villus length. A separate cohort of animals was injected with LPS (25 mg/kg) and followed 7 days for survival. RESULTS Mice whose diet was supplemented with TDCA had significantly increased survival. After LPS-induced injury, mice supplemented with TDCA showed decreased intestinal apoptosis by both H&E and caspase-3. They also had increased intestinal proliferation by 5-bromo-2'deoxyuridine staining and increased villus length. CONCLUSIONS Dietary TDCA supplementation alleviates mucosal damage and improves survival after LPS-induced intestinal injury. Taurodeoxycholic acid is protective of the intestinal mucosa by increasing resistance to injury-induced apoptosis, stimulating enterocyte proliferation, and increasing villus length. Taurodeoxycholic acid supplementation also results in an increased survival benefit. Therefore, bile acid supplementation may potentially protect the intestine from injury or infection.
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Affiliation(s)
- Erin E. Perrone
- Department of Pediatric Surgery, University of Maryland Medical Center, 22 S. Greene St, Rm N4E37, Baltimore, MD 21201,Department of Surgery, Wayne State University School of Medicine, 4201 St. Antoine, UHC-6C, Detroit, MI 48201
| | - Chen Chen
- Department of Pediatric Surgery, University of Maryland Medical Center, 22 S. Greene St, Rm N4E37, Baltimore, MD 21201
| | - Shannon W. Longshore
- Department of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, One Children's Place, Suite 5S60, St. Louis MO 63110,Department of Surgery, University of California, Davis Medical Center, 2315 Stockton Blvd., Sacramento, CA 95817
| | - Oneybuchi Okezie
- Department of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, One Children's Place, Suite 5S60, St. Louis MO 63110
| | - Brad W. Warner
- Department of Pediatric Surgery, St. Louis Children's Hospital, Washington University School of Medicine, One Children's Place, Suite 5S60, St. Louis MO 63110
| | - Chen-Chih Sun
- Department of Pathology, University of Maryland Medical Center, 22 S. Greene St, Rm N4E37, Baltimore, MD 21201
| | - Samuel M. Alaish
- Department of Pediatric Surgery, University of Maryland Medical Center, 22 S. Greene St, Rm N4E37, Baltimore, MD 21201
| | - Eric D. Strauch
- Department of Pediatric Surgery, University of Maryland Medical Center, 22 S. Greene St, Rm N4E37, Baltimore, MD 21201
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Emami CN, Petrosyan M, Giuliani S, Williams M, Hunter C, Prasadarao NV, Ford HR. Role of the host defense system and intestinal microbial flora in the pathogenesis of necrotizing enterocolitis. Surg Infect (Larchmt) 2010; 10:407-17. [PMID: 19943775 DOI: 10.1089/sur.2009.054] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Necrotizing enterocolitis (NEC) is a devastating disease that affects primarily the intestine of premature infants. Despite recent advances in neonatology, NEC remains a major cause of morbidity and mortality in neonates. Neonatal mucosal defenses and adherence of bacterial pathogens may play an important role in the pathogenesis of NEC. METHODS Review and synthesis of pertinent literature. RESULTS Putative factors that have been implicated in the pathogenesis of NEC include abnormal patterns of gut colonization by bacteria, immaturity of the host immune system and mucosal defense mechanisms, intestinal ischemia, formula feeding, and loss of intestinal epithelial barrier integrity. CONCLUSION Host defenses and intestinal microbial ecology are believed to play important roles in the pathogenesis of NEC. Commensal bacteria and probiotic therapy may be of therapeutic utility in the maintenance of the gut epithelial barrier.
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Affiliation(s)
- Claudia N Emami
- Department of Surgery, Childrens Hospital Los Angeles, Keck School of Medicine of University of Southern California, Los Angeles, California 90027, USA
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Guven A, Gundogdu G, Vurucu S, Uysal B, Oztas E, Ozturk H, Korkmaz A. Medical ozone therapy reduces oxidative stress and intestinal damage in an experimental model of necrotizing enterocolitis in neonatal rats. J Pediatr Surg 2009; 44:1730-5. [PMID: 19735816 DOI: 10.1016/j.jpedsurg.2009.01.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 11/21/2008] [Accepted: 01/08/2009] [Indexed: 11/25/2022]
Abstract
PURPOSE Necrotizing enterocolitis (NEC) remains a major cause of morbidity and death in neonates. Evidence suggests that an imbalance between activated proinflammatory response with inadequate antiinflammatory protection results in NEC. Ozone has been proposed as an antioxidant enzyme activator, immunomodulator, and cellular metabolic activator. Therefore, this study was designed to investigate whether medical ozone therapy is effective on neonatal rat model of NEC. MATERIALS AND METHODS Thirty-eight newborn Sprague-Dawley pups were randomly divided into 3 groups of NEC, NEC + ozone, and control (left to breast feed). Necrotizing enterocolitis was induced by enteral formula feeding and exposure to 100% carbon dioxide inhalation for 10 minutes after +4 degrees C cold exposures for 5 minutes and 97% oxygen for 5 minutes 2 times daily. The NEC + ozone group received 0.7 mg/kg per day ozone/oxygen mixture intraperitoneally for a total of 3 days after first day of NEC procedure. The pups were killed at fourth day, and their intestinal tissues were harvested for biochemical and histopathologic analysis. Blood sample from pups were also obtained. RESULTS The mortality rate and the weight loss were significantly higher in NEC group than control and treatment groups. Oxidative stress markers (malondialdehyde and protein carbonyl content) significantly increased and antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase) were significantly decreased in NEC group. All these biochemical changes were ameliorated in NEC + ozone group. Nitrate plus nitrite levels and serum tumor necrosis factor alpha were elevated in NEC group and reduced in treatment group. In addition, histopathologic injury score of NEC group was significantly higher than NEC + ozone group. CONCLUSION Ozone treatment significantly reduced the severity of NEC by modulating antioxidative defense and antiinflammatory protection in our experimental animal model.
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Affiliation(s)
- Ahmet Guven
- Department of Pediatric Surgery, Gulhane Military Medical Academy, Etlik, Ankara, Turkey.
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Guner YS, Ochoa CJ, Wang J, Zhang X, Steinhauser S, Stephenson L, Grishin A, Upperman JS. Peroxynitrite-induced p38 MAPK pro-apoptotic signaling in enterocytes. Biochem Biophys Res Commun 2009; 384:221-5. [PMID: 19393619 DOI: 10.1016/j.bbrc.2009.04.091] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Accepted: 04/19/2009] [Indexed: 01/02/2023]
Abstract
Enterocyte apoptosis in necrotizing enterocolitis is partly due to the elaboration of toxic intermediates of nitric oxide (NO), such as peroxynitrite (PN). Because p38 mitogen-activated protein kinase (MAPK) and serine-threonine kinase (AKT) are well-characterized pro- and anti-apoptotic mediators, respectively, we hypothesized that PN could induce enterocyte apoptosis via activation of p38 and deactivation of AKT. To test this hypothesis, the rat intestinal cell line, IEC-6, was treated with PN. PN caused phosphorylation of p38, its upstream activator, MKK3/6, and downstream effector, transcription factor ATF-2. PN-induced apoptosis was inhibited by the p38 inhibitor, SB202190, and by p38 siRNA. PN decreased AKT phosphorylation; this effect was abrogated by pre-treatment with SB202190 or p38 siRNA. PN exposure also increased the activity of the protein phosphatase 2A (PP2A). These data demonstrate that PN-mediated apoptosis depends on the p38 pathway and that p38 mediates deactivation of AKT survival pathways possibly by the involvement of PP2A.
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Affiliation(s)
- Yigit S Guner
- Childrens Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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26
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Petrosyan M, Guner YS, Williams M, Grishin A, Ford HR. Current concepts regarding the pathogenesis of necrotizing enterocolitis. Pediatr Surg Int 2009; 25:309-18. [PMID: 19301015 DOI: 10.1007/s00383-009-2344-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/11/2009] [Indexed: 02/07/2023]
Abstract
Necrotizing enterocolitis (NEC) is a devastating disease that predominantly affects premature neonates. The mortality associated with NEC has not changed appreciably over the past several decades. The underlying etiology of NEC remains elusive, although bacterial colonization of the gut, formula feeding, and perinatal stress have been implicated as putative risk factors. The disease is characterized by massive epithelial destruction, which results in gut barrier failure. The exact molecular and cellular mechanisms involved in this complex disease are poorly understood. Recent studies have provided significant insight into our understanding of the pathogenesis of NEC. Endogenous mediators such as prostanoids, cyclooxygenases, and nitric oxide may play a role in the development of gut barrier failure. Understanding the structural architecture of the gut barrier and the cellular mechanisms that are responsible for gut epithelial damage could lead to the development of novel diagnostic, prophylactic and therapeutic strategies in NEC.
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Affiliation(s)
- Mikael Petrosyan
- Childrens Hospital Los Angeles, Keck School of Medicine, University of Southern California, 4650 Sunset Blvd, Mailstop #72, Los Angeles, CA 90027, USA
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Martínez MC, Andriantsitohaina R. Reactive nitrogen species: molecular mechanisms and potential significance in health and disease. Antioxid Redox Signal 2009; 11:669-702. [PMID: 19014277 DOI: 10.1089/ars.2007.1993] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Reactive nitrogen species (RNS) are various nitric oxide-derived compounds, including nitroxyl anion, nitrosonium cation, higher oxides of nitrogen, S-nitrosothiols, and dinitrosyl iron complexes. RNS have been recognized as playing a crucial role in the physiologic regulation of many, if not all, living cells, such as smooth muscle cells, cardiomyocytes, platelets, and nervous and juxtaglomerular cells. They possess pleiotropic properties on cellular targets after both posttranslational modifications and interactions with reactive oxygen species. Elevated levels of RNS have been implicated in cell injury and death by inducing nitrosative stress. The aim of this comprehensive review is to address the mechanisms of formation and removal of RNS, highlighting their potential cellular targets: lipids, DNA, and proteins. The specific importance of RNS and their paradoxic effects, depending on their local concentration under physiologic conditions, is underscored. An increasing number of compounds that modulate RNS processing or targets are being identified. Such compounds are now undergoing preclinical and clinical evaluations in the treatment of pathologies associated with RNS-induced cellular damage. Future research should help to elucidate the involvement of RNS in the therapeutic effect of drugs used to treat neurodegenerative, cardiovascular, metabolic, and inflammatory diseases and cancer.
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Affiliation(s)
- M Carmen Martínez
- INSERM, U771, CNRS UMR, 6214, and Université d' Angers, Angers, France
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Guven A, Gundogdu G, Uysal B, Cermik H, Kul M, Demirbag S, Ozturk H, Oter S. Hyperbaric oxygen therapy reduces the severity of necrotizing enterocolitis in a neonatal rat model. J Pediatr Surg 2009; 44:534-40. [PMID: 19302854 DOI: 10.1016/j.jpedsurg.2008.06.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2008] [Revised: 05/09/2008] [Accepted: 06/15/2008] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Hyperbaric oxygen (HBO) therapy is known to increase oxygen concentration in tissues leading to induction of an adaptive increase in antioxidants, stimulation of angiogenesis, improvement of white blood cell action, and regulation of inflammatory process. Therefore, we tested the potential beneficial effect of HBO in neonatal rat model of necrotizing enterocolitis (NEC). MATERIALS AND METHODS Thirty newborn Sprague-Dawley rats, provided by the Experimental Research Council, Gulhane Military Medical Academy, Ankara,Turkey, were randomly divided into 3 groups as follows: NEC, NEC + HBO, and control. Necrotizing enterocolitis was induced by enteral formula feeding and exposure to hypoxia after cold stress at 4 degrees C and oxygen. The NEC + HBO group received HBO at 2.8 atmosphere absolute (ATA) for 90 minutes daily for 3 days. The pups were killed on the fourth day, and their intestinal tissues were harvested for biochemical and histopathologic analysis. Blood samples were also obtained from the pups. RESULTS The mortality rate was highest in the NEC group (3 pups in the NEC group vs 1 pup in the NEC + HBO group). Malondialdehyde and protein carbonyl content were significantly increased, whereas superoxide dismutase and glutathione peroxidase were significantly decreased in the NEC group. All these changes were similar to control levels in the NEC group by HBO treatment. Nitrate plus nitrite (NO(x)) levels and serum tumor necrosis factor alpha were increased in the NEC group and histopathologic injury score and apoptosis index in the NEC group were significantly higher than in the NEC + HBO group. CONCLUSION Hyperbaric oxygen significantly reduced the severity of NEC in our study.
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Affiliation(s)
- Ahmet Guven
- Department of Pediatric Surgery, Gulhane Military Medical Academy, 06017 Etlik, Ankara, Turkey
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Gayer CP, Chaturvedi LS, Wang S, Craig DH, Flanigan T, Basson MD. Strain-induced proliferation requires the phosphatidylinositol 3-kinase/AKT/glycogen synthase kinase pathway. J Biol Chem 2008; 284:2001-11. [PMID: 19047055 DOI: 10.1074/jbc.m804576200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The intestinal epithelium is repetitively deformed by shear, peristalsis, and villous motility. Such repetitive deformation stimulates the proliferation of intestinal epithelial cells on collagen or laminin substrates via ERK, but the upstream mediators of this effect are poorly understood. We hypothesized that the phosphatidylinositol 3-kinase (PI3K)/AKT cascade mediates this mitogenic effect. PI3K, AKT, and glycogen synthase kinase-3beta (GSK-3beta) were phosphorylated by 10 cycles/min strain at an average 10% deformation, and pharmacologic blockade of these molecules or reduction by small interfering RNA (siRNA) prevented the mitogenic effect of strain in Caco-2 or IEC-6 intestinal epithelial cells. Strain MAPK activation required PI3K but not AKT. AKT isoform-specific siRNA transfection demonstrated that AKT2 but not AKT1 is required for GSK-3beta phosphorylation and the strain mitogenic effect. Furthermore, overexpression of AKT1 or an AKT chimera including the PH domain and hinge region of AKT2 and the catalytic domain and C-tail of AKT1 prevented strain activation of GSK-3beta, but overexpression of AKT2 or a chimera including the PH domain and hinge region of AKT1 and the catalytic domain and C-tail of AKT2 did not. These data delineate a role for PI3K, AKT2, and GSK-3beta in the mitogenic effect of strain. PI3K is required for both ERK and AKT2 activation, whereas AKT2 is sequentially required for GSK-3beta. Furthermore, AKT2 specificity requires its catalytic domain and tail region. Manipulating this pathway may prevent mucosal atrophy and maintain the mucosal barrier in conditions such as ileus, sepsis, and prolonged fasting when peristalsis and villous motility are decreased and the mucosal barrier fails.
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Affiliation(s)
- Christopher P Gayer
- Department of Surgery, John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan 48301, USA
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Epidermal growth factor treatment decreases mortality and is associated with improved gut integrity in sepsis. Shock 2008; 30:36-42. [PMID: 18004230 DOI: 10.1097/shk.0b013e31815d0820] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Epidermal growth factor (EGF) is a cytoprotective peptide that has healing effects on the intestinal mucosa. We sought to determine whether systemic administration of EGF after the onset of sepsis improved intestinal integrity and decreased mortality. FVB/N mice were subjected to either sham laparotomy or 2 x 23 cecal ligation and puncture (CLP). Septic mice were further randomized to receive injection of either 150 microg kg(-1) d(-1) (i.p.) EGF or 0.9% saline (i.p.). Circulating EGF levels were decreased after CLP compared with sham animals but were unaffected by giving exogenous EGF treatment. In contrast, intestinal EGF levels increased after CLP and were further augmented by exogenous EGF treatment. Intestinal EGF receptor was increased after CLP, whether assayed by immunohistochemistry, real-time polymerase chain reaction, or Western blot, and exogenous EGF treatment decreased intestinal EGF receptor. Villus length decreased 2-fold between sham and septic animals, and EGF treatment resulted in near total restitution of villus length. Sepsis decreased intestinal proliferation and increased intestinal apoptosis. This was accompanied by increased expression of the proapoptotic proteins Bid and Fas-associated death domain, as well as the cyclin-dependent kinase inhibitor p21 cip1/waf Epidermal growth factor treatment after the onset of sepsis restored both proliferation and apoptosis to levels seen in sham animals and normalized expression of Bid, Fas-associated death domain, and p21 cip1/waf . To determine whether improvements in gut homeostasis were associated with a decrease in sepsis-induced mortality, septic mice with or without EGF treatment after CLP were followed 7 days for survival. Mortality decreased from 60% to 30% in mice treated with EGF after the onset of sepsis (P < 0.05). Thus, EGF may be a potential therapeutic agent for the treatment of sepsis in part due to its ability to protect intestinal integrity.
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Chokshi NK, Guner YS, Hunter CJ, Upperman JS, Grishin A, Ford HR. The role of nitric oxide in intestinal epithelial injury and restitution in neonatal necrotizing enterocolitis. Semin Perinatol 2008; 32:92-9. [PMID: 18346532 PMCID: PMC2390779 DOI: 10.1053/j.semperi.2008.01.002] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Necrotizing enterocolitis (NEC) is the most common life-threatening gastrointestinal disease encountered in the premature infant. Although the inciting events leading to NEC remain elusive, various risk factors, including prematurity, hypoxemia, formula feeding, and intestinal ischemia, have been implicated in the pathogenesis of NEC. Data from our laboratory and others suggest that NEC evolves from disruption of the intestinal epithelial barrier, as a result of a combination of local and systemic insults. We postulate that nitric oxide (NO), an important second messenger and inflammatory mediator, plays a key role in intestinal barrier failure seen in NEC. Nitric oxide and its reactive nitrogen derivative, peroxynitrite, may affect gut barrier permeability by inducing enterocyte apoptosis (programmed cell death) and necrosis, or by altering tight junctions or gap junctions that normally play a key role in maintaining epithelial monolayer integrity. Intrinsic mechanisms that serve to restore monolayer integrity following epithelial injury include enterocyte proliferation, epithelial restitution via enterocyte migration, and re-establishment of cell contacts. This review focuses on the biology of NO and the mechanisms by which it promotes epithelial injury while concurrently disrupting the intrinsic repair mechanisms.
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Affiliation(s)
- Nikunj K Chokshi
- Department of Pediatric Surgery, Childrens Hospital Los Angeles, Los Angeles, CA 90027, USA
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Clark JA, Coopersmith CM. Intestinal crosstalk: a new paradigm for understanding the gut as the "motor" of critical illness. Shock 2008; 28:384-93. [PMID: 17577136 PMCID: PMC2084394 DOI: 10.1097/shk.0b013e31805569df] [Citation(s) in RCA: 328] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
For more than 20 years, the gut has been hypothesized to be the "motor" of multiple organ dysfunction syndrome. As critical care research has evolved, there have been multiple mechanisms by which the gastrointestinal tract has been proposed to drive systemic inflammation. Many of these disparate mechanisms have proved to be important in the origin and propagation of critical illness. However, this has led to an unusual situation where investigators describing the gut as a "motor" revving the systemic inflammatory response syndrome are frequently describing wholly different processes to support their claim (i.e., increased apoptosis, altered tight junctions, translocation, cytokine production, crosstalk with commensal bacteria, etc). The purpose of this review is to present a unifying theory as to how the gut drives critical illness. Although the gastrointestinal tract is frequently described simply as "the gut," it is actually made up of (1) an epithelium; (2) a diverse and robust immune arm, which contains most of the immune cells in the body; and (3) the commensal bacteria, which contain more cells than are present in the entire host organism. We propose that the intestinal epithelium, the intestinal immune system, and the intestine's endogenous bacteria all play vital roles driving multiple organ dysfunction syndrome, and the complex crosstalk between these three interrelated portions of the gastrointestinal tract is what cumulatively makes the gut a "motor" of critical illness.
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Affiliation(s)
- Jessica A Clark
- Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
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Cetin S, Leaphart CL, Li J, Ischenko I, Hayman M, Upperman J, Zamora R, Watkins S, Ford HR, Wang J, Hackam DJ. Nitric oxide inhibits enterocyte migration through activation of RhoA-GTPase in a SHP-2-dependent manner. Am J Physiol Gastrointest Liver Physiol 2007; 292:G1347-58. [PMID: 17272518 DOI: 10.1152/ajpgi.00375.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Diseases of intestinal inflammation like necrotizing enterocolitis (NEC) are associated with impaired epithelial barrier integrity and the sustained release of intestinal nitric oxide (NO). NO modifies the cytoskeletal regulator RhoA-GTPase, suggesting that NO could affect barrier healing by inhibiting intestinal restitution. We now hypothesize that NO inhibits enterocyte migration through RhoA-GTPase and sought to determine the pathways involved. The induction of NEC was associated with increased enterocyte NO release and impaired migration of bromodeoxyuridine-labeled enterocytes from terminal ileal crypts to villus tips. In IEC-6 enterocytes, NO significantly inhibited enterocyte migration and activated RhoA-GTPase while increasing the formation of stress fibers. In parallel, exposure of IEC-6 cells to NO increased the phosphorylation of focal adhesion kinase (pFAK) and caused a striking increase in cell-matrix adhesiveness, suggesting a mechanism by which NO could impair enterocyte migration. NEC was associated with increased expression of pFAK in the terminal ileal mucosa of wild-type mice and a corresponding increase in disease severity compared with inducible NO synthase knockout mice, confirming the dependence of NO for FAK phosphorylation in vivo and its role in the pathogenesis of NEC. Strikingly, inhibition of the protein tyrosine phosphatase SHP-2 in IEC-6 cells prevented the activation of RhoA by NO, restored focal adhesions, and reversed the inhibitory effects of NO on enterocyte migration. These data indicate that NO impairs mucosal healing by inhibiting enterocyte migration through activation of RhoA in a SHP-2-dependent manner and support a possible role for SHP-2 as a therapeutic target in diseases of intestinal inflammation like NEC.
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Affiliation(s)
- Selma Cetin
- Div. of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
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Giannone PJ, Schanbacher BL, Bauer JA, Reber KM. Effects of prenatal lipopolysaccharide exposure on epithelial development and function in newborn rat intestine. J Pediatr Gastroenterol Nutr 2006; 43:284-90. [PMID: 16954948 DOI: 10.1097/01.mpg.0000232572.56397.d6] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND Maternal infection during pregnancy is associated with several neonatal morbidities, including periventricular leukomalacia and lung maldevelopment and injury. OBJECTIVE To test the hypothesis that responses to prenatal maternal exposure to lipopolysaccharide (LPS) alter intestinal epithelial development and function in newborn rats. DESIGN/METHODS Timed-pregnancy female Sprague-Dawley rats were administered either 2 mg LPS or an equal volume of isotonic saline by intraperitoneal injection at E16 and allowed to deliver naturally. Pups were weighed and then killed at days of life (DOL) 0, 3, 7 and 14. Morphometric parameters were measured on standard hematoxylin and eosin-stained sections using ImagePro software. Immunohistochemistry was performed with antibody specific for inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine on distal ileal intestinal samples analyzed at each time point. Optical density was determined and quantified for site-specific regions of intestinal sections. On DOL 14, in vivo mucosal permeability was measured by feeding rats fluorescein isothiocyanate (FITC) via orogastric tube; and then serum FITC was measured. RESULTS There were no significant differences in pup weights. Mucosal thicknesses were significantly less in the distal ileum from pups born to LPS-exposed dams on DOL 0, 3 and 7 (P < 0.001). On DOL 0, iNOS protein concentrations in the prenatal LPS treatment group were significantly greater than iNOS protein concentrations in the distal villus (P < 0.001), proximal villus/crypts (P < 0.01), submucosa (P < 0.001) and muscularis (P < 0.01) in the distal small intestine of the control group. On DOL 3, 7 and 14, significant differences were observed in iNOS protein concentrations in the distal villus and submucosal regions between groups (P < 0.001). On DOL 0, 3, 7 and 14, 3-nitrotyrosine immunostaining was significantly elevated in the prenatal LPS-exposed pups in the distal villus on (P < 0.001) as well as in the submucosa on DOL 3 (P < 0.001). Serum FITC measurement was significantly greater in prenatal LPS exposure group at DOL 14 (P < 0.001). CONCLUSIONS Maternal exposure to LPS during pregnancy alters intestinal growth and regulation of iNOS in the newborn rat intestine.
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Affiliation(s)
- Peter J Giannone
- Section of Neonatology, Department of Pediatrics, Center for Cardiovascular Medicine, Columbus Children's Research Institute, Columbus, Ohio 43205, USA.
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Ford HR. Mechanism of nitric oxide-mediated intestinal barrier failure: insight into the pathogenesis of necrotizing enterocolitis. J Pediatr Surg 2006; 41:294-9. [PMID: 16481238 DOI: 10.1016/j.jpedsurg.2005.11.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Henri R Ford
- Department of Surgery, University of Southern California Keck School of Medicine, Los Angeles, CA 90027, USA.
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Roxström-Lindquist K, Ringqvist E, Palm D, Svärd S. Giardia lamblia-induced changes in gene expression in differentiated Caco-2 human intestinal epithelial cells. Infect Immun 2006; 73:8204-8. [PMID: 16299316 PMCID: PMC1307045 DOI: 10.1128/iai.73.12.8204-8208.2005] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The parasitic protozoan Giardia lamblia is a worldwide cause of diarrhea, but the mechanism of disease remains elusive. The parasite colonizes the small intestinal epithelium, known to be a sensor for the presence of enteric pathogens, without invading or causing severe inflammation. In this study we investigated the epithelial cell response to G. lamblia. Differentiated Caco-2 cells were infected with G. lamblia isolate WB-A11, and the transcriptome of the intestinal cells was analyzed after 1.5, 6, and 18 h of interaction, using oligonucleotide microarrays. A large number of genes displayed changed expression patterns, showing the complexity of the interaction between G. lamblia and intestinal cells. A novel chemokine profile (CCL2, CCL20, CXCL1, CXCL2, and CXCL3) was induced that was different from the response induced by enteric pathogens causing intestinal inflammation. Several genes involved in stress regulation changed their expression. These findings indicate that the intestinal epithelium senses the G. lamblia infection, and this is important for induction of innate and adaptive immunity. The induced stress response can be important in the pathogenesis.
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Affiliation(s)
- Katarina Roxström-Lindquist
- Department of Parasitology, Microbiology and Tumor Biology Center, Karolinska Institutet, SE-17177 Stockholm, Sweden
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El-Helou V, Bel-Hadj S, Drapeau J, Clement R, Gosselin H, Calderone A. Nitric oxide-mediated inhibition of DNA synthesis was attenuated in hypertrophied neonatal rat ventricular myocytes. Nitric Oxide 2005; 14:316-26. [PMID: 16309934 DOI: 10.1016/j.niox.2005.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Revised: 09/28/2005] [Accepted: 10/06/2005] [Indexed: 11/16/2022]
Abstract
The antiproliferative action of nitric oxide (NO) has been well established and increased production was reported in the infarcted rat heart. Concomitantly, increased DNA synthesis and hyperplasia of cardiac myocytes were documented in the hypertrophied myocardium. Despite these observations, the effect of NO on DNA synthesis in hypertrophied cardiac myocytes remains unexamined. Hypertrophy of the non-infarcted left ventricle (NILV) in 1-week post-MI rats was characterized by the increased prepro-ANP and reduction of alpha-myosin heavy chain protein expression. Inducible NO synthase was expressed in the NILV and associated with a concomitant attenuation of MnSuperoxide dismutase protein content. The latter data suggest that an antiproliferative action of NO in the hypertrophied NILV may proceed via either a cyclic GMP-dependent pathway and/or facilitated by a peroxynitrite-dependent mechanism. In neonatal rat ventricular myocytes (NNVM), the NO donor S-nitroso-N-acetyl-penicillamine (SNAP) promoted a dose-dependent attenuation of DNA synthesis via a cyclic GMP-independent pathway. The permeable superoxide dismutase mimetic and peroxynitrite scavenger MnTBAP abrogated SNAP-dependent attenuation of DNA synthesis in NNVM. MnTBAP failed to inhibit SNAP-mediated recruitment of extracellular signal regulated kinase 1/2 (ERK1/2) but partially attenuated p38 phosphorylation. In hypertrophied NNVM induced by norepinephrine, SNAP-mediated peroxynitrite-dependent inhibition of DNA synthesis, ERK1/2 and p38 phosphorylation were significantly attenuated. Collectively, these data suggest that despite a favourable environment for NO and subsequent peroxynitrite generation in the NILV, hypertrophied cardiac myocytes may be partially refractory to their biological actions.
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Affiliation(s)
- Viviane El-Helou
- Department of Physiology, University of Montreal, Montreal, Que., Canada
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Husain KD, Stromberg PE, Woolsey CA, Turnbull IR, Dunne WM, Javadi P, Buchman TG, Karl IE, Hotchkiss RS, Coopersmith CM. Mechanisms of decreased intestinal epithelial proliferation and increased apoptosis in murine acute lung injury*. Crit Care Med 2005; 33:2350-7. [PMID: 16215392 PMCID: PMC1317567 DOI: 10.1097/01.ccm.0000182797.89252.a3] [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: 01/30/2023]
Abstract
OBJECTIVES The aim of this study was to determine the effects of acute lung injury on the gut epithelium and examine mechanisms underlying changes in crypt proliferation and apoptosis. The relationship between severity and timing of lung injury to intestinal pathology was also examined. DESIGN Randomized, controlled study. SETTING University research laboratory. SUBJECTS Genetically inbred mice. INTERVENTIONS Following induction of acute lung injury, gut epithelial proliferation and apoptosis were assessed in a) C3H/HeN wild-type and C3H/HeJ mice, which lack functional Toll-like receptor 4 (n = 17); b) C57Bl/6 mice that received monoclonal anti-tumor necrosis factor-alpha or control antibody (n = 22); and c) C57Bl/6 wild-type and transgenic mice that overexpress Bcl-2 in their gut epithelium (n = 21). Intestinal epithelial proliferation and death were also examined in animals with differing degrees of lung inflammation (n = 24) as well as in a time course analysis following a fixed injury (n = 18). MEASUREMENTS AND MAIN RESULTS Acute lung injury caused decreased proliferation and increased apoptosis in crypt epithelial cells in all animals studied. C3H/HeJ mice had higher levels of proliferation than C3H/HeN animals without additional changes in apoptosis. Anti-tumor necrosis factor-alpha antibody had no effect on gut epithelial proliferation or death. Overexpression of Bcl-2 did not change proliferation despite decreasing gut apoptosis. Proliferation and apoptosis were not correlated to severity of lung injury, as gut alterations were lost in mice with more severe acute lung injury. Changes in both gut epithelial proliferation and death were apparent within 12 hrs, but proliferation was decreased 36 hrs following acute lung injury while apoptosis returned to normal. CONCLUSIONS Acute lung injury causes disparate effects on crypt proliferation and apoptosis, which occur, at least in part, through differing mechanisms involving Toll-like receptor 4 and Bcl-2. Severity of lung injury does not correlate with perturbations in proliferation or death in the gut epithelium, and acute lung injury-induced changes in intestinal epithelial proliferation persist longer than those in apoptosis.
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Affiliation(s)
| | | | | | | | | | | | - Timothy G. Buchman
- Departments of Surgery
- Medicine, and
- Anesthesiology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110
| | | | - Richard S. Hotchkiss
- Departments of Surgery
- Medicine, and
- Anesthesiology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110
| | - Craig M. Coopersmith
- Departments of Surgery
- Anesthesiology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110
- Address correspondence to: Craig M Coopersmith, MD, Washington University School of Medicine, 660 S Euclid Ave, Campus Box 8109, Saint Louis, MO 63110, Phone: 314-362-9342, Fax: 314-362-1602 E-mail:
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40
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Zamora R, Grishin A, Wong C, Boyle P, Wang J, Hackam D, Upperman JS, Tracey KJ, Ford HR. High-mobility group box 1 protein is an inflammatory mediator in necrotizing enterocolitis: protective effect of the macrophage deactivator semapimod. Am J Physiol Gastrointest Liver Physiol 2005; 289:G643-52. [PMID: 15947118 DOI: 10.1152/ajpgi.00067.2005] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
High-mobility group box 1 (HMGB1) is a late mediator of endotoxemia known to stimulate the production of proinflammatory cytokines that are putative mediators of intestinal inflammation associated with necrotizing enterocolitis (NEC). We hypothesized that HMGB1 is also involved in the pathogenesis of NEC. We examined the expression of HMGB1 and the effect of the novel drug semapimod on intestinal inflammation in an experimental model of NEC in neonatal rats. Newborn rats were subjected to hypoxia and fed a conventional formula by gavage (FFH) or were breast fed (BF). Rats were killed on day 4, and the distal ileum was harvested for morphological studies and Western blot analysis. FFH newborn rats but not BF controls developed intestinal inflammation similar to the histological changes observed in human NEC. We found that the expression of HMGB1 and its receptor for advanced glycation end products (RAGE) as well as that of other apoptosis/inflammation-related proteins (Bad, Bax, inducible nitric oxide synthase, and cyclooxygenase 2) was upregulated in the ileal mucosa of FFH newborn rats compared with BF animals. Administration of the drug semapimod inhibited the upregulation of those proteins and partially protected the animals against the FFH-induced intestinal injury. Elevated levels of HMGB1 were also found in ileal samples from infants undergoing intestinal resection for acute NEC. Our results implicate HMGB1 and RAGE as important mediators of enterocyte cell death and hypoxia-induced injury in NEC and support the hypothesis that inhibitors such as semapimod might play a therapeutic role in chronic intestinal inflammation characterized by this animal model.
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MESH Headings
- Animals
- Animals, Newborn
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Apoptosis/drug effects
- Blotting, Western
- Cell Death/drug effects
- Cells, Cultured
- Cytokines/antagonists & inhibitors
- Enterocolitis, Necrotizing/mortality
- Enterocolitis, Necrotizing/pathology
- Enterocolitis, Necrotizing/prevention & control
- Female
- Genes, bcl-2
- Glycation End Products, Advanced/metabolism
- HMGB1 Protein/biosynthesis
- HMGB1 Protein/physiology
- Hydrazones/pharmacology
- Inflammation Mediators/physiology
- Intestines/pathology
- Lipopolysaccharides/pharmacology
- Macrophages/drug effects
- Nitric Oxide Synthase/biosynthesis
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Pregnancy
- Rats
- Rats, Sprague-Dawley
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Ruben Zamora
- Dept. of Pediatric Surgery, Children's Hospital of Pittsburgh, PA 15213, USA.
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41
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Rangasamy T, Guo J, Mitzner WA, Roman J, Singh A, Fryer AD, Yamamoto M, Kensler TW, Tuder RM, Georas SN, Biswal S. Disruption of Nrf2 enhances susceptibility to severe airway inflammation and asthma in mice. ACTA ACUST UNITED AC 2005; 202:47-59. [PMID: 15998787 PMCID: PMC2212893 DOI: 10.1084/jem.20050538] [Citation(s) in RCA: 474] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Oxidative stress has been postulated to play an important role in the pathogenesis of asthma; although a defect in antioxidant responses has been speculated to exacerbate asthma severity, this has been difficult to demonstrate with certainty. Nuclear erythroid 2 p45-related factor 2 (Nrf2) is a redox-sensitive basic leucine zipper transcription factor that is involved in the transcriptional regulation of many antioxidant genes. We show that disruption of the Nrf2 gene leads to severe allergen-driven airway inflammation and hyperresponsiveness in mice. Enhanced asthmatic response as a result of ovalbumin sensitization and challenge in Nrf2-disrupted mice was associated with more pronounced mucus cell hyperplasia and infiltration of eosinophils into the lungs than seen in wild-type littermates. Nrf2 disruption resulted in an increased expression of the T helper type 2 cytokines interleukin (IL)-4 and IL-13 in bronchoalveolar lavage fluid and in splenocytes after allergen challenge. The enhanced severity of the asthmatic response from disruption of the Nrf2 pathway was a result of a lowered antioxidant status of the lungs caused by lower basal expression, as well as marked attenuation, of the transcriptional induction of multiple antioxidant genes. Our studies suggest that the responsiveness of Nrf2-directed antioxidant pathways may act as a major determinant of susceptibility to allergen-mediated asthma.
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Affiliation(s)
- Tirumalai Rangasamy
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
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Upperman JS, Potoka D, Grishin A, Hackam D, Zamora R, Ford HR. Mechanisms of nitric oxide-mediated intestinal barrier failure in necrotizing enterocolitis. Semin Pediatr Surg 2005; 14:159-66. [PMID: 16084403 DOI: 10.1053/j.sempedsurg.2005.05.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Necrotizing enterocolitis (NEC) is the leading intestinal emergency in premature infants. The underlying etiology of NEC remains elusive, but hypoxic conditions and early enteral feeding are consistently implicated as the main risk factors in the pathogenesis of NEC. We postulate that nitric oxide (NO) plays a key role as a molecular signaling "hub" in the generation of gut barrier failure in NEC. Clinical studies suggest that inflammatory cytokines and excessive NO production may contribute to the pathogenesis of NEC. One of the major challenges in defining the critical signaling pathways that lead to the development of NEC is the lack of specific biochemical markers that consistently delineate the early stages of NEC. Intestinal pathology and molecular markers derived from late-stage NEC represent end-stage findings and thus provide little insight into the early events that led to intestinal inflammation. Such markers may not represent viable therapeutic targets for the treatment or prevention of NEC. Therefore, novel strategies are needed to identify the patients at risk for NEC and define the clinically relevant molecules that characterize the early stages of NEC. This review will examine the mechanisms of NO-mediated gut barrier failure and propose novel genetic-based approaches for elucidating the critical molecular pathways in NEC.
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Affiliation(s)
- Jeffrey S Upperman
- Department of Surgery, University of Pittsburgh and Children's Hospital of Pittsburgh, Pittsburgh, Pennsylania 15213, USA.
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Abstract
BACKGROUND Glutathione (GSH) is the major intracellular antioxidant protecting against free radical-mediated damage. Oxidative stress is implicated in the pathogenesis of necrotizing enterocolitis (NEC), and damage could be enhanced by a relative deficiency of GSH. We hypothesized that infants with NEC would have lower levels of erythrocyte GSH when compared with controls. METHODS Total erythrocyte GSH concentration (per gram of hemoglobin [g Hb]) was determined in blood samples from infants with NEC (n = 16) referred for surgical intervention. Nonseptic infants referred for other conditions (eg, patent ductus arteriosus ligation) served as controls (n = 10). RESULTS Controls and infants with NEC were demographically similar. Mean erythrocyte GSH concentration in infants with NEC was 0.076 +/- 0.004 micromol/g Hb and in controls it was 0.078 +/- 0.005 micromol/g Hb (P = .73). There was no significant correlation between GSH concentration and weight, gestational age, or C-reactive protein levels. In infants with NEC, there was no difference in GSH levels between infants with stage 2 and stage 3 diseases nor between those who died and survived, but a trend toward lower GSH levels in infants with more extensive diseases exists. CONCLUSIONS Total GSH levels are similar in infants with NEC and controls. It is possible that a relative rather than absolute deficiency of antioxidant compounds exists and may contribute to the development of NEC.
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Affiliation(s)
- Nigel J Hall
- Department of Paediatric Surgery, Institute of Child Health and Great Ormond Street Hospital for Children NHS Trust, WC1N 1EH London, UK
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44
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Hackam DJ, Upperman JS, Grishin A, Ford HR. Disordered enterocyte signaling and intestinal barrier dysfunction in the pathogenesis of necrotizing enterocolitis. Semin Pediatr Surg 2005; 14:49-57. [PMID: 15770588 DOI: 10.1053/j.sempedsurg.2004.10.025] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in neonates, and is characterized by the development of diffuse intestinal necrosis in the stressed, pre-term infant. Systemic stress causes a breakdown in the intestinal mucosal barrier, which leads to translocation of bacteria and endotoxin and the initiation of a signaling response within the enterocyte. This review summarizes recent evidence defining a clear role that defective enterocyte signaling plays in the pathogenesis of NEC through the following mechanisms: 1) The localized production of nitric oxide by villus enterocytes results in an increase in enterocyte apoptosis and impaired proliferation; 2) The translocation of endotoxin results in a PI3K-dependent activation of RhoA-GTPase within the enterocyte leading to decreased enterocyte migration and impaired restitution; 3) Dysregulated sodium-proton exchange within the enterocyte by endotoxin renders the enterocyte monolayer more susceptible to damage in the face of the acidic microenvironment characteristic of systemic sepsis; and 4) Endotoxin causes a p38-dependent release of the pro-inflammatory molecule COX-2 by the enterocyte, which potentiates the systemic inflammatory response. An understanding of the mechanisms by which disordered enterocyte signaling contributes to the pathogenesis of barrier failure and NEC--through these and other mechanisms--may lead to the identification of novel therapeutic approaches for this devastating disease.
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Affiliation(s)
- David J Hackam
- Division of Pediatric Surgry, Children's Hospital of Pittsburgh, Pennsylvania 15217, USA
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45
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Al-Ghoul WM, Khan M, Fazal N, Sayeed MM. Mechanisms of postburn intestinal barrier dysfunction in the rat: Roles of epithelial cell renewal, E-cadherin, and neutrophil extravasation*. Crit Care Med 2004; 32:1730-9. [PMID: 15286551 DOI: 10.1097/01.ccm.0000132896.62368.01] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Our group has previously shown that the intestinal epithelium exhibits increased postburn barrier permeability and bacterial translocation associated with deranged neutrophil activity. The purpose of this investigation is to explore possible underlying intestinal structural mechanisms, leading to those functional changes with emphasis on (1) neutrophil influx and extravasation in the intestinal lamina propria 1-3 days after burn and (2) enterocyte proliferation, migration, apoptosis, and E-cadherin junctional epithelium levels 3 days after burn. DESIGN Freshly isolated ileum specimens were quick frozen, then cut by a cryostat into 30-micron-thick sections. Sections from day 1 postburn rats were immunostained with (1) anti-granulocyte or anti-elastase antibodies to assess neutrophil influx or (2) combined anti-granulocyte and anti-von Willebrand factor double immunolabeling to compare levels of neutrophil extravasation. Sections from day 3 postburn rats were immunostained with (1) bromodeoxyuridine immunohistochemistry 1, 3, 6, or 18 hrs after bromodeoxyuridine injection to assess enterocyte proliferation and migration, (2) cytokeratin-18 M30-immunohistochemistry to compare levels of enterocyte apoptosis, and (3) E-cadherin immunohistochemistry to compare junctional E-cadherin integrity. Ileal myeloperoxidase activity and bacterial translocation of Enterococcus faecalis were assessed biochemically and by E. faecalis-specific bacterial cultures, respectively, in day 3 postburn rats. SETTING : Research laboratories in a medical center and an academic institution. SUBJECTS Male Sprague-Dawley rats given sham treatment or treatment as a burn model with full-thickness skin scald over 30% total body surface area. CONCLUSIONS We report (1) increased levels of neutrophil influx and extravasation in villi lamina propriae, including elastase-positive cells (postburn day 1), (2) heightened levels of intestinal myeloperoxidase activity (postburn day 3), (3) decreased levels of epithelial cell proliferation, migration, and E-cadherin (postburn day 3), and (4) increased enterocyte apoptosis and E. faecalis bacterial translocation (postburn day 3). Based on these structural and functional abnormalities, we propose a mechanism for burn injury-related intestinal barrier dysfunction that includes increased trans- and para-cellular leakage caused by impaired enterocyte renewal and decreased junctional E-cadherin levels subsequent to increased neutrophil influx and extravasation within the villus lamina propria microenvironment.
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Affiliation(s)
- Walid M Al-Ghoul
- Trauma/Critical Care Labs, Department of Surgery, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
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