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Probiotic/synbiotic therapy for treating critically ill patients from a gut microbiota perspective. Dig Dis Sci 2013; 58:23-32. [PMID: 22903218 PMCID: PMC3557374 DOI: 10.1007/s10620-012-2334-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 07/18/2012] [Indexed: 12/13/2022]
Abstract
The gut is an important target organ for stress caused by severe insults such as sepsis, trauma, burn, shock, bleeding and infection. Severe insult to the gut is considered to have an important role in promoting infectious complications and multiple organ dysfunction syndrome. These are sequelae of interactions between deteriorated intestinal epithelium, the immune system and commensal bacteria. The gut is the "motor" of multiple organ failure, and now it is recognized that gut dysfunction is a causative factor in disease progression. The gut flora and environment are significantly altered in critically ill patients, and the number of obligate anaerobes is associated with prognosis. Synbiotic therapy is a combination of probiotics and prebiotics. Probiotic, prebiotic and synbiotic treatment has been shown to be a promising therapy to maintain and repair the gut microbiota and gut environment. In the critically ill, such as major abdominal surgery, trauma and ICU patients, synbiotic therapy has been shown to significantly reduce septic complications. Further basic and clinical research would clarify the underlying mechanisms of the therapeutic effect of probiotic/synbiotic treatment and define the appropriate conditions for use.
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252
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He GZ, Zhou KG, Zhang R, Wang YK, Chen XF. Impact of intestinal ischemia/reperfusion and lymph drainage on distant organs in rats. World J Gastroenterol 2012; 18:7271-7278. [PMID: 23326132 PMCID: PMC3544029 DOI: 10.3748/wjg.v18.i48.7271] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 09/19/2012] [Accepted: 11/15/2012] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the impact of intestinal ischemia/reperfusion (I/R) injury and lymph drainage on distant organs in rats.
METHODS: Thirty-two Sprague-Dawley male rats, weighing 280-320 g, were randomly divided into blank, sham, I/R, and ischemia/reperfusion and drainage (I/R + D) groups (n = 8). All rats were subjected to 60 min ischemia by clamping the superior mesenteric artery, followed by 120 min reperfusion. The rats in the I/R + D group received intestinal lymph drainage for 180 min. In the sham group, the abdominal cavity was opened for 180 min, but the rats received no treatment. The blank group served as a normal and untreated control. A chromogenic limulus assay kit was used for quantitative detection of serum endotoxin. The serum concentrations of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, soluble cell adhesion molecules (sICAM-1), and high mobility group protein box 1 (HMGB1) were determined with an enzyme-linked immunosorbent assay kit. Histological evaluations of the intestine, liver, kidney, and lung were performed by hematoxylin and eosin staining and immunohistochemistry. HMGB1 protein expression was assayed by western blot analysis.
RESULTS: The serum levels of endotoxin and HMGB1 in the I/R and I/R + D groups were significantly higher than those in the sham group (endotoxin, I/R and I/R + D vs sham: 0.033 ± 0.004 EU/mL, 0.024 ± 0.003 EU/mL vs 0.017 ± 0.009 EU/mL, respectively, P < 0.05; HMGB1, I/R and I/R + D vs sham: 5.473 ± 0.963 EU/mL, 4.906 ± 0.552 EU/mL vs 0.476 ± 0.406 EU/mL, respectively, P < 0.05). In addition, endotoxin and HMGB1 were significantly lower in the I/R + D group compared to the I/R group (P < 0.05). The serum inflammatory factors IL-6, IL-1β, and sICAM-1 in the I/R and I/R + D groups were significantly higher than those in the sham group (IL-6, I/R and I/R + D vs sham: 41.773 ± 9.753 pg/mL, 19.204 ± 4.136 pg/mL vs 11.566 ± 2.973 pg/mL, respectively, P < 0.05; IL-1β, I/R and I/R + D vs sham: 144.646 ± 29.378 pg/mL, 65.829 ± 10.888 pg/mL vs 38.178 ± 7.157 pg/mL, respectively, P < 0.05; sICAM-1, I/R and I/R + D vs sham: 97.360 ± 12.714 ng/mL, 48.401 ± 6.547 ng/mL vs 33.073 ± 5.957 ng/mL, respectively; P < 0.05). The serum TNF-α in the I/R group were significantly higher than in the sham group (45.863 ± 11.553 pg/mL vs 18.863 ± 6.679 pg/mL, respectively, P < 0.05). These factors were significantly lower in the I/R + D group compared to the I/R group (P < 0.05). The HMGB1 immunohistochemical staining results showed no staining or apparent injury in the blank group, and slight staining at the top of the microvillus was detected in the sham group. In the I/R group, both the top of villi and the basement membrane were stained for HMGB1 in most areas, and injury in the I/R + D group was less than that in the I/R group. HMGB1 expression in the liver, kidney, and lung of rats in the I/R + D group was significantly lower than the rats in the I/R group (P < 0.05).
CONCLUSION: Lymph drainage could block the “gut-lymph” pathway, improve intestinal barrier function, and attenuate distant organ injury incurred by intestinal I/R.
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Dominguez JA, Xie Y, Dunne WM, Yoseph BP, Burd EM, Coopersmith CM, Davidson NO. Intestine-specific Mttp deletion decreases mortality and prevents sepsis-induced intestinal injury in a murine model of Pseudomonas aeruginosa pneumonia. PLoS One 2012; 7:e49159. [PMID: 23145105 PMCID: PMC3493497 DOI: 10.1371/journal.pone.0049159] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 10/04/2012] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The small intestine plays a crucial role in the pathophysiology of sepsis and has been referred to as the "motor" of the systemic inflammatory response. One proposed mechanism is that toxic gut-derived lipid factors, transported in mesenteric lymph, induce systemic injury and distant organ failure. However, the pathways involved are yet to be defined and the role of intestinal chylomicron assembly and secretion in transporting these lipid factors is unknown. Here we studied the outcome of sepsis in mice with conditional, intestine-specific deletion of microsomal triglyceride transfer protein (Mttp-IKO), which exhibit a block in chylomicron assembly together with lipid malabsorption. METHODOLOGY/PRINCIPAL FINDINGS Mttp-IKO mice and controls underwent intratracheal injection with either Pseudomonas aeruginosa or sterile saline. Mttp-IKO mice exhibited decreased seven-day mortality, with 0/20 (0%) dying compared to 5/17 (29%) control mice (p<0.05). This survival advantage in Mttp-IKO mice, however, was not associated with improvements in pulmonary bacterial clearance or neutrophil infiltration. Rather, Mttp-IKO mice exhibited protection against sepsis-associated decreases in villus length and intestinal proliferation and were also protected against increased intestinal apoptosis, both central features in control septic mice. Serum IL-6 levels, a major predictor of mortality in human and mouse models of sepsis, were elevated 8-fold in septic control mice but remained unaltered in septic Mttp-IKO mice. Serum high density lipoprotein (HDL) levels were reduced in septic control mice but were increased in septic Mttp-IKO mice. The decreased levels of HDL were associated with decreased hepatic expression of apolipoprotein A1 in septic control mice. CONCLUSIONS/SIGNIFICANCE These studies suggest that strategies directed at blocking intestinal chylomicron secretion may attenuate the progression and improve the outcome of sepsis through effects mediated by metabolic and physiological adaptations in both intestinal and hepatic lipid flux.
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Affiliation(s)
- Jessica A. Dominguez
- Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Yan Xie
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - W. Michael Dunne
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Benyam P. Yoseph
- Emory Center for Critical Care and Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Eileen M. Burd
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Craig M. Coopersmith
- Emory Center for Critical Care and Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Nicholas O. Davidson
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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Liu D, Guo S, Guo Y. Xylanase supplementation to a wheat-based diet alleviated the intestinal mucosal barrier impairment of broiler chickens challenged by Clostridium perfringens. Avian Pathol 2012; 41:291-8. [PMID: 22702457 DOI: 10.1080/03079457.2012.684089] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The present study was carried out to evaluate the protective effects of xylanase on the intestinal mucosal barrier in broiler chickens challenged with Clostridium perfringens in a 21-day experiment. A total of 336 1-day-old male broiler chicks (Ross 308) were assigned to four treatment groups. A 2×2 factorial arrangement of treatments was used in a randomized complete block design to study the effects of enzyme addition (with or without xylanase 5500 U/kg wheat-based diet), pathogen challenge (with or without C. perfringens challenge), and their interactions. Most C. perfringens-challenged birds had a congested mucosa and focal haemorrhagic lesions in the jejunum. Xylanase addition tended to reduce (P=0.09) the intestinal lesion score in the challenged birds. C. perfringens challenge resulted in decreased villus height/crypt depth ratio in the jejunum and ileum (P<0.05). Xylanase supplementation significantly increased this ratio in the jejunum (P<0.05) and also had the tendency to decrease crypt depth (P=0.065) and increase this ratio in the ileum (P=0.087). Xylanase addition significantly decreased the plasma endotoxin levels of the birds challenged with C. perfringens (P<0.05). Occludin mRNA expression in the jejunum and ileum was significantly decreased by C. perfringens challenge (P<0.05), but xylanase addition significantly increased its expression in the ileum. Xylanase supplementation also significantly increased MUC2 mRNA expression in the ileum (P<0.05). C. perfringens challenge resulted in a significant increase in apoptotic index in all three intestinal segments (P<0.05), but xylanase supplementation obviously decreased apoptotic index in the ileum (P<0.05). In conclusion, xylanase supplementation could alleviate the impairment of intestinal mucosal barrier induced by C. perfringens challenge.
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Affiliation(s)
- Dan Liu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, PR China
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255
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Bosmann M, Ward PA. The inflammatory response in sepsis. Trends Immunol 2012; 34:129-36. [PMID: 23036432 DOI: 10.1016/j.it.2012.09.004] [Citation(s) in RCA: 351] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 09/06/2012] [Accepted: 09/07/2012] [Indexed: 12/18/2022]
Abstract
The pathophysiology of sepsis and its accompanying systemic inflammatory response syndrome (SIRS) and the events that lead to multiorgan failure and death are poorly understood. It is known that, in septic humans and rodents, the development of SIRS is associated with a loss of the redox balance, but SIRS can also develop in noninfectious states. In addition, a hyperinflammatory state develops, together with impaired innate immune functions of phagocytes, immunosuppression, and complement activation, collectively leading to septic shock and lethality. Here, we discuss recent insights into the signaling pathways in immune and phagocytic cells that underlie sepsis and SIRS and consider how these might be targeted for therapeutic interventions to reverse or attenuate pathways that lead to lethality during sepsis.
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Affiliation(s)
- Markus Bosmann
- The University of Michigan Medical School, Department of Pathology, 1301 Catherine Road, Ann Arbor, MI 48109-5602, USA
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256
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Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis. Shock 2012; 38:68-75. [PMID: 22592747 DOI: 10.1097/shk.0b013e318259abdb] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and killed 24 h later. Septic animals had a marked increase in intestinal epithelial apoptosis by both hematoxylin-eosin and active caspase 3 staining. Methicillin-resistant S. aureus-induced intestinal apoptosis was associated with an increase in the expression of the proapoptotic proteins Bid and Bax and the antiapoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1, and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid-/- mice and animals with intestine-specific overexpression of Bcl-2 had decreased intestinal apoptosis compared with wild-type animals. In contrast, Fas ligand-/- mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. Pseudomonas aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. Methicillin-resistant S. aureus pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways, although the former may be more functionally significant.
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257
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Wang F, Li Q, Wang C, Tang C, Li J. Dynamic alteration of the colonic microbiota in intestinal ischemia-reperfusion injury. PLoS One 2012; 7:e42027. [PMID: 22848694 PMCID: PMC3407053 DOI: 10.1371/journal.pone.0042027] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 06/29/2012] [Indexed: 12/15/2022] Open
Abstract
Background Intestinal ischemia-reperfusion (I/R) plays an important role in critical illnesses. Gut flora participate in the pathogenesis of the injury. This study is aimed at unraveling colonic microbiota alteration pattern and identifying specific bacterial species that differ significantly as well as observing colonic epithelium change in the same injury model during the reperfusion time course. Methodology/Principal Findings Denaturing gradient gel electrophoresis (DGGE) was used to monitor the colonic microbiota of control rats and experimental rats that underwent 0.5 hour ischemia and 1, 3, 6, 12, 24, and 72 hours following reperfusion respectively. The microbiota similarity, bacterial diversity and species that characterized the dysbiosis were estimated based on the DGGE profiles using a combination of statistical approaches. The interested bacterial species in the gel were cut and sequenced and were subsequently quantified and confirmed with real-time PCR. Meanwhile, the epithelial barrier was checked by microscopy and D-lactate analysis. Colonic flora changed early and differed significantly at 6 hours after reperfusion and then started to recover. The shifts were characterized by the increase of Escherichia coli and Prevotella oralis, and Lactobacilli proliferation together with epithelia healing. Conclusion/Significance This study shows for the first time that intestinal ischemia-reperfusion results in colonic flora dysbiosis that follows epithelia damage, and identifies the bacterial species that contribute most.
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Affiliation(s)
- Fan Wang
- Research Institute of General Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Qiurong Li
- Research Institute of General Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Chenyang Wang
- Research Institute of General Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Chun Tang
- Research Institute of General Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
| | - Jieshou Li
- Research Institute of General Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, China
- * E-mail:
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258
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Weismüller K, Hofer S, Weigand MA. [Perioperative protection of the gastrointestinal tract]. Anaesthesist 2012; 61:722-7. [PMID: 22790474 DOI: 10.1007/s00101-012-2005-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The gastrointestinal tract is a complex organ system. Dysfunctions of this organ system may evoke a variety of consequences for the entire organism and influence the inflammatory response in particular. In perioperative medicine, nutrition, prokinetics, peridural anesthesia, catecholamines and volume therapy can be applied in order to improve the gastrointestinal functional or at least to avoid further aggravation. Early enteral nutrition is especially important in the reduction of postsurgical ileus and infectious complications. Also, prokinetics and thoracic peridural anesthesia favorably affect postsurgical ileus. Norepinephrine, if necessary in combination with dobutamine, seems to have fewer negative effects on splanchnic perfusion than epinephrine. The data on volume therapy remain controversial but fluid balance has to be calculated very carefully also considering enteral loss of fluids. Thus, in order to treat and avoid gastrointestinal problems after surgery and to prevent negative effects for the complete organism, multimodal concepts with regard to detail are required.
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Affiliation(s)
- K Weismüller
- Klinik für Anaesthesiologie, Operative Intensivmedizin und Schmerztherapie, Universitätsklinikum Giessen und Marburg GmbH, Campus Giessen, Deutschland.
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Osuka A, Shimizu K, Ogura H, Tasaki O, Hamasaki T, Asahara T, Nomoto K, Morotomi M, Kuwagata Y, Shimazu T. Prognostic impact of fecal pH in critically ill patients. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:R119. [PMID: 22776285 PMCID: PMC3580696 DOI: 10.1186/cc11413] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 07/10/2012] [Indexed: 01/07/2023]
Abstract
Introduction We have reported that altered gut flora is associated with septic complications and eventual death in critically ill patients with systemic inflammatory response syndrome. It is unclear how fecal pH affects these patients. We sought to determine whether fecal pH can be used as an assessment tool for the clinical course of critically ill patients. Methods Four hundred ninety-one fecal samples were collected from 138 patients who were admitted to the Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Japan. These patients were treated in the intensive care unit for more than 2 days. Fecal pH, fecal organic acids, and fecal bacteria counts were measured and compared by survived group and nonsurvived group, or nonbacteremia group and bacteremia group. Logistic regression was used to estimate relations between fecal pH, age, sex, or APACHE II score and mortality, and incidence of bacteremia. Differences in fecal organic acids or fecal bacteria counts among acidic, neutral, and alkaline feces were analyzed. Results The increase of fecal pH 6.6 was significantly associated with the increased mortality (odds ratio, 2.46; 95% confidence interval, 1.25 to 4.82) or incidence of bacteremia (3.25; 1.67 to 6.30). Total organic acid was increased in acidic feces and decreased in alkaline feces. Lactic acid, succinic acid, and formic acid were the main contributors to acidity in acidic feces. In alkaline feces, acetic acid was significantly decreased. Propionic acid was markedly decreased in both acidic and alkaline feces compared with neutral feces. No differences were noted among the groups in bacterial counts. Conclusions The data presented here demonstrate that the fecal pH range that extended beyond the normal range was associated with the clinical course and prognosis of critically ill patients.
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Yang J, Radulescu A, Chen CL, Zhang HY, James IO, Besner GE. Heparin-binding epidermal growth factor-like growth factor improves intestinal barrier function and reduces mortality in a murine model of peritonitis. Surgery 2012; 153:52-62. [PMID: 22703966 DOI: 10.1016/j.surg.2012.04.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 04/12/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND The morbidity and mortality associated with bacterial peritonitis remain high. Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) is a potent intestinal cytoprotective agent. The aim of this study was to evaluate the effect of HB-EGF in a model of murine peritonitis. METHODS HB-EGF(-/-) knockout (KO) mice and their HB-EGF(+/+) wild-type (WT) counterparts were subjected to sham operation, cecal ligation and puncture (CLP), or CLP with HB-EGF treatment (800 μg/kg IP daily). Villous length, intestinal permeability, intestinal epithelial cell (IEC) apoptosis, bacterial load in peritoneal fluid (PF) and mesenteric lymph nodes (MLN), inflammatory cytokine levels, and survival were determined. RESULTS After exposure to CLP, HB-EGF KO mice had significantly shorter villi (1.37 ± 0.13 vs 1.96 ± 0.4 relative units; P < .03), increased intestinal permeability (17.01 ± 5.18 vs 11.50 ± 4.67 nL/min/cm2; P < .03), increased IEC apoptotic indices (0.0093 ± 0.0033 vs 0.0016 ± 0.0014; P < .01), and increased bacterial counts in PF (25,313 ± 17,558 vs 11,955 ± 6,653 colony forming units [CFU]/mL; P < .05) and MLN (19,009 ± 11,200 vs 5,948 ± 2,988 CFU/mL/g; P < .01) compared with WT mice. Administration of HB-EGF to WT and HB-EGF KO mice exposed to CLP led to significantly increased villous length and decreased intestinal permeability, IEC apoptosis and bacterial counts in MLN (P < .05). Survival of HB-EGF KO mice subjected to CLP was significantly improved with administration of HB-EGF (P < .05). CONCLUSION HB-EGF gene KO increases susceptibility to peritonitis-induced intestinal injury, which can be reversed by administration of HB-EGF. These results support a protective role of HB-EGF in peritonitis-induced sepsis.
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Affiliation(s)
- Jixin Yang
- Department of Pediatric Surgery, Nationwide Children's Hospital, Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, and The Ohio State University College of Medicine, Columbus, OH, USA
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261
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Protective effects of nonionic triblock copolymers on bile acid-mediated epithelial barrier disruption. Shock 2012; 36:451-7. [PMID: 21937955 DOI: 10.1097/shk.0b013e31822d8de1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Translocation of bacteria and other luminal factors from the intestine following surgical injury can be a major driver of critical illness. Bile acids have been shown to play a key role in the loss of intestinal epithelial barrier function during states of host stress. Experiments to study the ability of nonionic block copolymers to abrogate barrier failure in response to bile acid exposure are described. In vitro experiments were performed with the bile salt sodium deoxycholate on Caco-2 enterocyte monolayers using transepithelial electrical resistance to assay barrier function. A bisphenol A coupled triblock polyethylene glycol (PEG), PEG 15-20, was shown to prevent sodium deoxycholate-induced barrier failure. Enzyme-linked immunosorbent assay, lactate dehydrogenase, and caspase 3-based cell death detection assays demonstrated that bile acid-induced apoptosis and necrosis were prevented with PEG 15-20. Immunofluorescence microscopic visualization of the tight junctional protein zonula occludens 1 (ZO-1) demonstrated that PEG 15-20 prevented significant changes in tight junction organization induced by bile acid exposure. Preliminary transepithelial electrical resistance-based studies examining structure-function correlates of polymer protection against bile acid damage were performed with a small library of PEG-based copolymers. Polymer properties associated with optimal protection against bile acid-induced barrier disruption were PEG-based compounds with a molecular weight greater than 10 kd and amphiphilicity. The data demonstrate that PEG-based copolymer architecture is an important determinant that confers protection against bile acid injury of intestinal epithelia.
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262
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Inhibition of hypoxia inducible factor-1α ameliorates lung injury induced by trauma and hemorrhagic shock in rats. Acta Pharmacol Sin 2012; 33:635-43. [PMID: 22465950 DOI: 10.1038/aps.2012.5] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
AIM Ischemia/reperfusion is an initial triggering event that leads to gut-induced acute lung injury (ALI). In this study, we investigated whether hypoxia inducible factor-1α (HIF-1α) played a role in the pathogenesis of lung injury induced by trauma and hemorrhagic shock (T/HS). METHODS Male Wistar rats underwent laparotomy and hemorrhagic shock for 60 min. Sham-shock animals underwent laparotomy but without hemorrhagic shock. After resuscitation for 3 hr, the rats were sacrificed. Morphologic changes of the lungs and intestines were examined. Bronchoalveolar lavage fluid (BALF) was collected. Lung water content, pulmonary myeloperoxidase (MPO) activity and the levels of malondialdehyde (MDA), nitrite/nitrate, TNF-α, IL-1β, and IL-6 in the lungs were measured. The gene expression of pulmonary HIF-1α and iNOS, and HIF-1α transcriptional activity in the lungs were also assessed. The apoptosis in the lungs was determined using TUNEL assay and cleaved caspase-3 expression. RESULTS Lung and intestinal injuries induced by T/HS were characterized by histological damages and a significant increase in lung water content. Compared to the sham-shock group, the BALF cell counts, the pulmonary MPO activity and the MDA, nitrite/nitrate, TNF-α, IL-1β, and IL-6 levels in the T/HS group were significantly increased. Acute lung injury was associated with a higher degree of pulmonary HIF-1α and iNOS expression as well as apoptosis in the lungs. Intratracheal delivery of HIF-1α inhibitor YC-1 (1 mg/kg) significantly attenuated lung injury, and reduced pulmonary HIF-1α and iNOS expression and HIF-1α transcriptional activity in the T/HS group. CONCLUSION Local inhibition of HIF-1α by YC-1 alleviates the lung injury induced by T/HS. Our results provide novel insight into the pathogenesis of T/HS-induced ALI and a potential therapeutic application.
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Epidermal growth factor improves survival and prevents intestinal injury in a murine model of pseudomonas aeruginosa pneumonia. Shock 2012; 36:381-9. [PMID: 21701422 DOI: 10.1097/shk.0b013e31822793c4] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mortality from pneumonia is mediated, in part, through extrapulmonary causes. Epidermal growth factor (EGF) has broad cytoprotective effects, including potent restorative properties in the injured intestine. The purpose of this study was to determine the efficacy of EGF treatment following Pseudomonas aeruginosa pneumonia. FVB/N mice underwent intratracheal injection of either P. aeruginosa or saline and were then randomized to receive either systemic EGF or vehicle beginning immediately or 24 h after the onset of pneumonia. Systemic EGF decreased 7-day mortality from 65% to 10% when initiated immediately after the onset of pneumonia and to 27% when initiated 24 h after the onset of pneumonia. Even though injury in pneumonia is initiated in the lungs, the survival advantage conferred by EGF was not associated with improvements in pulmonary pathology. In contrast, EGF prevented intestinal injury by reversing pneumonia-induced increases in intestinal epithelial apoptosis and decreases in intestinal proliferation and villus length. Systemic cytokines and kidney and liver function were unaffected by EGF therapy, although EGF decreased pneumonia-induced splenocyte apoptosis. To determine whether the intestine was sufficient to account for extrapulmonary effects induced by EGF, a separate set of experiments was done using transgenic mice with enterocyte-specific overexpression of EGF (IFABP-EGF [intestinal fatty acid-binding protein linked to mouse EGF] mice), which were compared with wild-type mice subjected to pneumonia. IFABP-EGF mice had improved survival compared with wild-type mice following pneumonia (50% vs. 28%, respectively, P < 0.05) and were protected from pneumonia-induced intestinal injury. Thus, EGF may be a potential adjunctive therapy for pneumonia, mediated in part by its effects on the intestine.
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264
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Silvestri L, van Saene HKF, Petros AJ. Selective digestive tract decontamination in critically ill patients. Expert Opin Pharmacother 2012; 13:1113-29. [PMID: 22533385 DOI: 10.1517/14656566.2012.681778] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Selective decontamination of the digestive tract (SDD) has been proposed to prevent endogenous and exogenous infections and to reduce mortality in critically ill patients. Although the efficacy of SDD has been confirmed by randomized controlled trials (RCTs) and systematic reviews, SDD has been the subject of intense controversy, based mainly on an insufficient evidence of efficacy and on concerns about resistance. AREAS COVERED This article reviews the philosophy, the current evidence on the efficacy of SDD and the issue of emergence of resistance. All SDD RCTs were searched using Embase and Medline, with no restriction of language, gender or age. Personal archives were also explored, including abstracts from major scientific meetings; references in papers and published meta-analyses on SDD were crosschecked. Up-to-date evidence of the impact of SDD on carriage, infections and mortality is presented, and the efficacy of SDD in selected patient groups was investigated, along with the problem of the emergence of resistance. EXPERT OPINION SDD significantly reduces the number of infections of the lower respiratory tract and bloodstream, multiple organ failure and mortality. It also controls resistance, particularly when the full protocol of parenteral and enteral antimicrobials is used.
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Affiliation(s)
- Luciano Silvestri
- Department of Emergency, Unit of Anaesthesia and Intensive Care, Presidio Ospedaliero di Gorizia, Via Fatebenefratelli 34, 34170 Gorizia, Italy.
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265
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Proinflammatory chemokines in the intestinal lumen contribute to intestinal dysfunction during endotoxemia. Shock 2012; 37:63-9. [PMID: 22089201 DOI: 10.1097/shk.0b013e31823cbff1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Intestinal failure is common in patients with septic shock, with dysfunction of the gut often manifesting as both a cause and consequence of their critical illness. Most studies investigating the pathogenesis of intestinal failure focus on the systemic aspect, although few data examine the inflammatory signaling in the intestinal lumen. Having previously demonstrated apical/luminal chemokine secretion in an in vitro model of intestinal inflammation, we hypothesized that endotoxemia would induce secretion of proinflammatory chemokines into the intestinal lumen. In addition, we examined the contribution of these mediators to intestinal dysmotility. C57/BL6 male mice were injected intraperitoneally with LPS. Serum, intestinal tissue, and intestinal luminal contents were harvested for cytokine analysis. For intestinal motility studies, a transit assay was performed after oral gavage of chemokines. Caco-2 cells grown on Transwell culture inserts were used to examine the role of the intestinal epithelium in chemokine secretion. Monocyte chemoattractant protein 1 (MCP-1/CCL2) and macrophage-derived chemokine (MDC/CCL22) were secreted into the lumen of multiple segments of the gut during endotoxemia in mice. In vitro work showed that the intestinal epithelium participates in monocyte chemoattractant protein 1 and MDC secretion and expresses the CCR2 and CCR4 receptors for these chemokines. Intestinal transit studies show that oral gavage of MDC results in impaired gut motility. This study demonstrates that the intestinal lumen is an active compartment in the gut's inflammatory response. Proinflammatory chemokines are secreted into the intestinal lumen during endotoxemia. These intraluminal chemokines contribute to intestinal dysmotility, complicating intestinal failure.
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266
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McGuire MF, Sriram Iyengar M, Mercer DW. Data driven linear algebraic methods for analysis of molecular pathways: application to disease progression in shock/trauma. J Biomed Inform 2012; 45:372-87. [PMID: 22200681 PMCID: PMC3346262 DOI: 10.1016/j.jbi.2011.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 12/09/2011] [Accepted: 12/10/2011] [Indexed: 12/24/2022]
Abstract
MOTIVATION Although trauma is the leading cause of death for those below 45years of age, there is a dearth of information about the temporal behavior of the underlying biological mechanisms in those who survive the initial trauma only to later suffer from syndromes such as multiple organ failure. Levels of serum cytokines potentially affect the clinical outcomes of trauma; understanding how cytokine levels modulate intra-cellular signaling pathways can yield insights into molecular mechanisms of disease progression and help to identify targeted therapies. However, developing such analyses is challenging since it necessitates the integration and interpretation of large amounts of heterogeneous, quantitative and qualitative data. Here we present the Pathway Semantics Algorithm (PSA), an algebraic process of node and edge analyses of evoked biological pathways over time for in silico discovery of biomedical hypotheses, using data from a prospective controlled clinical study of the role of cytokines in multiple organ failure (MOF) at a major US trauma center. A matrix algebra approach was used in both the PSA node and PSA edge analyses with different matrix configurations and computations based on the biomedical questions to be examined. In the edge analysis, a percentage measure of crosstalk called XTALK was also developed to assess cross-pathway interference. RESULTS In the node/molecular analysis of the first 24h from trauma, PSA uncovered seven molecules evoked computationally that differentiated outcomes of MOF or non-MOF (NMOF), of which three molecules had not been previously associated with any shock/trauma syndrome. In the edge/molecular interaction analysis, PSA examined four categories of functional molecular interaction relationships--activation, expression, inhibition, and transcription--and found that the interaction patterns and crosstalk changed over time and outcome. The PSA edge analysis suggests that a diagnosis, prognosis or therapy based on molecular interaction mechanisms may be most effective within a certain time period and for a specific functional relationship.
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Affiliation(s)
- Mary F McGuire
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA.
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267
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Schwarte LA, Schwartges I, Scheeren TWL, Schober P, Picker O. The differential effects of recombinant brain natriuretic peptide, nitroglycerine and dihydralazine on systemic oxygen delivery and gastric mucosal microvascular oxygenation in dogs. Anaesthesia 2012; 67:501-507. [PMID: 22352680 DOI: 10.1111/j.1365-2044.2011.07047.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Brain natriuretic peptide has vasodilatory properties and may thus increase splanchnic perfusion and oxygenation. We compared the effects of recombinant brain natriuretic peptide on gastric mucosal microvascular haemoglobin oxygenation (reflectance spectrophotometry) and systemic variables with those of equi-hypotensive doses of two other vasodilators (nitroglycerine and dihydralazine). Chronically instrumented, healthy dogs were randomly allocated to receive on different days, one of the three drugs (nitroglycerine and dihydralazine doses titrated to reduce mean arterial pressure by ∼20%). Brain natriuretic peptide significantly increased gastric mucosal microvascular haemoglobin oxygenation selectively, i.e. without concomitant haemodynamic effects. In contrast, the other vasodilators either did not increase gastric mucosal microvascular haemoglobin oxygenation at all (nitroglycerine), or did so only with marked increases in other systemic haemodynamic variables (dihydralazine). Our data suggest a potential role of recombinant brain natriuretic peptide selectively for increasing microvascular mucosal oxygenation. Studies are required to extend these findings to the clinical setting.
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Affiliation(s)
- L A Schwarte
- Department of Anaesthesiology, VU University Medical Center, Amsterdam, The Netherlands
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268
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McConnell KW, Coopersmith CM. Organ failure avoidance and mitigation strategies in surgery. Surg Clin North Am 2012; 92:307-19, ix. [PMID: 22414415 DOI: 10.1016/j.suc.2012.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Postoperative organ failure is a challenging disease process that is better prevented than treated. Providers should use close observation and clinical judgment, and checklists of best practices to minimize the risk of organ failure in their patients. The treatment of multiorgan dysfunction syndrome (MODS) generally remains supportive, outside of rapid initiation of source control (when appropriate) and targeted antibiotic therapy. More specific treatments may be developed as the complex pathophysiology of MODS is better understood and more homogenous patient populations are selected for study.
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Affiliation(s)
- Kevin W McConnell
- Acute and Critical Care Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA
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269
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Andersson A, Rundgren M, Kalman S, Rooyackers O, Brattstrom O, Oldner A, Eriksson S, Frithiof R. Gut microcirculatory and mitochondrial effects of hyperdynamic endotoxaemic shock and norepinephrine treatment. Br J Anaesth 2012; 108:254-61. [DOI: 10.1093/bja/aer379] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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270
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Sánchez-Miralles A, Castellanos G, Badenes R, Conejero R. [Abdominal compartment syndrome and acute intestinal distress syndrome]. Med Intensiva 2012; 37:99-109. [PMID: 22244213 DOI: 10.1016/j.medin.2011.11.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 11/18/2011] [Accepted: 11/22/2011] [Indexed: 12/19/2022]
Abstract
Seriously ill patients frequently present intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) as complications, and the associated mortality is very high. This review offers an update on the most controversial aspects of these entities: factors favoring their appearance, the most common causes, prognosis, and methods of measuring intra-abdominal pressure (IAP), physiopathological consequences in relation to the different organs and systems, and the currently accepted treatment measures (medical and/or surgical). Simultaneously to the strictly physical mechanisms of injury, such as direct compression of intra-abdominal organs and vessels, the transmission of IAP to other compartments, and the drop in cardiac output, a series of immune-inflammatory mediators generated in the intestine itself may also intervene. Hypoperfusion, sustained ischemia and the ischemia-reperfusion phenomenon, would act upon the microbiota, intestinal epithelium and intestinal immune system, triggering a systemic inflammatory response and multiorgan dysfunction that appears in the final stages of ACS.
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Affiliation(s)
- A Sánchez-Miralles
- Servicio de Medicina Intensiva, Hospital Universitario San Juan de Alicante, Alicante, España
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271
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Slone EA, Pope MR, Roth M, Welti R, Fleming SD. TLR9 is dispensable for intestinal ischemia/reperfusion-induced tissue damage. AMERICAN JOURNAL OF CLINICAL AND EXPERIMENTAL IMMUNOLOGY 2012; 1:124-135. [PMID: 23205322 PMCID: PMC3509382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 09/17/2012] [Indexed: 05/16/2024]
Abstract
The mortality rate due to intestinal ischemia/reperfusion (IR) remains at 60-80%. As toll-like receptor (TLR) 4 has been shown to be critical for IR injury in several organs, including the intestine, and TLR9 is necessary for IR-induced damage of the liver, we investigated the hypothesis that TLR9 is involved in intestinal IR-induced damage. Wildtype (C57Bl/6) and TLR9(-/-) mice were subjected to intestinal IR or Sham treatment. Several markers of damage and inflammation were assessed, including mucosal injury, eicosanoid production, cytokine secretion and complement deposition. Although IR-induced injury was not altered, PGE(2) production was decreased in TLR9(-/-) mice. Attenuated PGE(2) production was not due to differences in percentage of lipids or COX-2 transcription. The data indicate that TLR9 is not required for IR-induced injury or inflammation of the intestine.
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Affiliation(s)
- Emily Archer Slone
- Division of Biology, 18 Ackert Hall, Kansas State University, Manhattan, KS 66506, USA
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272
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Preventing Enterocyte Damage by Maintenance of Mean Arterial Pressure During Major Nonabdominal Surgery in Children. Shock 2012; 37:22-7. [DOI: 10.1097/shk.0b013e318237d638] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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273
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The effects of n-3 PUFA and intestinal lymph drainage on high-mobility group box 1 and Toll-like receptor 4 mRNA in rats with intestinal ischaemia-reperfusion injury. Br J Nutr 2011; 108:883-92. [PMID: 22186663 DOI: 10.1017/s0007114511006040] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The aim of the present study was to investigate the impacts of n-3 PUFA and lymph drainage (D) on intestinal ischaemia-reperfusion (I/R) injury in rats. A total of forty-eight Sprague-Dawley male rats were randomly divided into three groups (n 16): normal diet (N), enteral nutrition (EN) and EN plus n-3 PUFA. Each group was further divided into lymph drainage (I/R+D) and non-drainage (I/R) sub-groups (n 8). After 5 d with different nutrition regimens, the rats were subjected to 60 min ischaemia by clamping the superior mesenteric artery, followed by 120 min reperfusion. At the same time, the rats in the I/R+D sub-groups were treated with intestinal lymph drainage for 180 min. Organs were harvested and we detected the cytokine, endotoxin, and expression of Toll-like receptor (TLR) 4 mRNA and its endogenous ligand high-mobility group box 1 (HMGB1). We found that the serum levels of HMGB1, inflammatory cytokine and endotoxin in the three I/R+D sub-groups were significantly lower than those in the N (I/R) and EN (I/R) sub-groups (P < 0·05). The activation of NF-κB and the expression of HMGB1 and TLR4 mRNA significantly increased in the jejunum, ileum, liver and lung after intestinal I/R injury, but notably lower in the I/R+D groups than those in I/R (P < 0·05). The injury degree and HMGB1 expression were decreased in the n-3 PUFA group than in the N and EN groups. We preliminarily concluded that nutrition with n-3 PUFA and/or intestinal lymph drainage may reduce HMGB1 and inflammatory cytokine in serum and lymph and inhibit the expression and signal transmission of TLR4 mRNA, thereby alleviating intestinal I/R injury in rats.
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274
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Zhang HY, James I, Chen CL, Besner GE. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) preserves gut barrier function by blocking neutrophil-endothelial cell adhesion after hemorrhagic shock and resuscitation in mice. Surgery 2011; 151:594-605. [PMID: 22153812 DOI: 10.1016/j.surg.2011.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 10/07/2011] [Indexed: 11/17/2022]
Abstract
BACKGROUND We have shown that heparin-binding epidermal growth factor-like growth factor (HB-EGF) protects the intestines from injury in several different animal models, including hemorrhagic shock and resuscitation (HS/R). The current study was designed to explore the mechanisms underlying the anti-inflammatory role of HB-EGF in preservation of gut barrier function after injury. METHODS In vivo, HS/R was induced in wild-type and neutropenic mice, with or without administration of HB-EGF, and intestinal permeability determined by use of the everted gut sac method. In vitro, cultured human umbilical vein endothelial cells (HUVECs) and freshly isolated human peripheral blood mononuclear cells (PMNs) were used to determine the effects of HB-EGF on HUVEC-PMN adhesion, reactive oxygen species production in PMN, adhesion molecule expression in HUVEC and PMN, and the signaling pathways involved. RESULTS We found that administration of HB-EGF to healthy mice led to preservation of gut barrier function after HS/R. Likewise, induction of neutropenia in mice also led to preservation of gut barrier function after HS/R. Administration of HB-EGF to neutropenic mice did not lead to further improvement in gut barrier function. In vitro studies showed that HB-EGF decreased neutrophil-endothelial cell (PMN-EC) adherence by down-regulating adhesion molecule expression in EC via the phosphoinositide 3-kinase-Akt pathway, and by inhibiting adhesion molecule surface mobilization and reactive oxygen species production in PMN. CONCLUSION These results indicate that HB-EGF preserves gut barrier function by inhibiting PMN and EC activation, thereby blocking PMN-EC adherence after HS/R in mice, and support the future use of HB-EGF in disease states manifested by hypoperfusion injury.
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Affiliation(s)
- Hong-yi Zhang
- Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
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275
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Niklasson L, Sundh H, Fridell F, Taranger GL, Sundell K. Disturbance of the intestinal mucosal immune system of farmed Atlantic salmon (Salmo salar), in response to long-term hypoxic conditions. FISH & SHELLFISH IMMUNOLOGY 2011; 31:1072-1080. [PMID: 21959038 DOI: 10.1016/j.fsi.2011.09.011] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Revised: 08/29/2011] [Accepted: 09/09/2011] [Indexed: 05/31/2023]
Abstract
The gastrointestinal (GI) tract has many important biological functions. One is to serve as a barrier between the fish and the external environment. A decreased physical barrier function of the intestine may lead to increased inflow of luminal content and subsequent activation of the intestinal mucosal immune system. This activation is governed by the ability of various compounds to induce cytokine release and immune cell activity, leading to an immune response. In mammals, the impact of stress on the intestinal barrier is well documented and results in increased intestinal permeability and thus increased stimulation of the mucosal immune system. Fish reared in sea cages may at times be exposed to unfavourable environmental conditions leading to chronic stress and disturbed intestinal integrity. This change in permeability may increase the exposure of the mucosal immune system to activating compounds. In the present study, the effect of a prolonged stress on the intestinal mucosal immune system of fish is therefore addressed. Atlantic salmon were exposed to low levels (50%) of dissolved oxygen (DO) for 6-7 weeks in consecutive experiments performed at 8 and 16 °C. Immune parameters were assessed in terms of mRNA expression of the key cytokines, interleukin-1β (IL-1β), IL-8, IL-10, interferon-γ (IFNγ) and transforming growth factor-β (TGFβ) as well as the immune regulatory inhibitor of nuclear factor κB (IκB). In the experiment at 8 °C also mucosal neutrophil infiltration was monitored. Subjecting the fish to low DO levels at 8 °C resulted in an increased mucosal neutrophil infiltration together with a down-regulation of IκB. At the higher temperature, 16 °C, low DO levels created decreased expression of the pro-inflammatory cytokine IL-1β in both intestinal regions as well as an increased expression of IL-10 in the proximal intestine. These results suggest that husbandry conditions in sea cages with DO levels as low as 50% clearly affects the intestinal mucosal immune system and results in a chronic inflammation. Moreover, the effects of low DO levels on the immune factors examined were more pronounced in the 16 °C experiment suggesting additive effects of high temperatures.
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Affiliation(s)
- L Niklasson
- Fish Endocrinology Laboratory, Department of Zoology/Zoophysiology, University of Gothenburg, P.O. Box 463, S-405 30 Gothenburg, Sweden.
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276
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Kristóf K, Madách K, Sándor N, Iványi Z, Király A, Erdei A, Tulassay E, Gál J, Bajtay Z. Impact of molecular mimicry on the clinical course and outcome of sepsis syndrome. Mol Immunol 2011; 49:512-7. [PMID: 22024415 DOI: 10.1016/j.molimm.2011.09.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 09/28/2011] [Accepted: 09/29/2011] [Indexed: 12/27/2022]
Abstract
We investigated the impact of molecular mimicry between pathogenic microbes and their antigenic surrounding on the clinical course and outcome of pneumonia induced sepsis. Using mathematical prediction, we estimated the mimicry tendency of the identified pathogenic flora of patients with the human proteome as well as intestinal microbes. Since gut bacteria become invasive and hostile in critical illness, mimicry between these organisms and the infectious flora is expected to be rather hyperinflammatory type, in contrast to the expectedly tolerogenic self versus pathogen cross-reactions. Differential effects of these two kinds of cross-reactions were studied. The predicted similarity of the identified pathogenic flora and intestinal microbes was higher in non-survivor patients compared to survivors (P=0.019). Higher values of "pathogen versus intestinal flora/pathogen versus human proteome" mimicry ratios (inflammatory quotients) were associated with mortality at a higher extent of significance (P<0.01), and correlated with admission APACHE II disease severity scores (R=0.311; P=0.017). We also found a correlation between the previously reported sepsis mortality rates by causative agent and the corresponding inflammatory quotients of these pathogens (R=0.738; P<0.05). Gram negative species showed higher similarity to intestinal bacteria and reached higher inflammatory quotients compared to Gram positives (P=0.01 and P<0.01, respectively). The disadvantageous effect of "pathogen versus intestinal flora" mimicry - presumably due to the extension of inflammation from the infectious focus to the already injured gut - is in accordance with the gut-lymph hypothesis, assessing that the destruction of the intestinal symbiosis culminates in the formation of damageous gut origin lymph. Our results raise the idea that molecular mimicry between pathogenic microbes and their antigenic surrounding might be a contributing factor behind the clinically and experimentally observed differences in microbiologically distinct forms of sepsis syndrome.
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Affiliation(s)
- Katalin Kristóf
- Eötvös Loránd University, Department of Immunology, Pázmány P. s. 1/C, H-1117 Budapest, Hungary.
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277
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Orsini JA. Laminitis: prevention and early intervention in surgical and medical case management. J Equine Vet Sci 2011. [DOI: 10.1016/j.jevs.2011.09.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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278
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Correlation between protection against sepsis by probiotic therapy and stimulation of a novel bacterial phylotype. Appl Environ Microbiol 2011; 77:7749-56. [PMID: 21926217 DOI: 10.1128/aem.05428-11] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Prophylactic probiotic therapy has shown beneficial effects in an experimental rat model for acute pancreatitis on the health status of the animals. Mechanisms by which probiotic therapy interferes with severity of acute pancreatitis and associated sepsis, however, are poorly understood. The aims of this study were to identify the probiotic-induced changes in the gut microbiota and to correlate these changes to disease outcome. Duodenum and ileum samples were obtained from healthy and diseased rats subjected to pancreatitis for 7 days and prophylactically treated with either a multispecies probiotic mixture or a placebo. Intestinal microbiota was characterized by terminal-restriction fragment length polymorphism (T-RFLP) analyses of PCR-amplified 16S rRNA gene fragments. These analyses showed that during acute pancreatitis the host-specific ileal microbiota was replaced by an "acute pancreatitis-associated microbiota." This replacement was not reversed by administration of the probiotic mixture. An increase, however, was observed in the relative abundance of a novel bacterial phylotype most closely related to Clostridium lituseburense and referred to as commensal rat ileum bacterium (CRIB). Specific primers targeting the CRIB 16S rRNA gene sequence were developed to detect this phylotype by quantitative PCR. An ileal abundance of CRIB 16S rRNA genes of more than 7.5% of the total bacterial 16S rRNA gene pool was correlated with reduced duodenal bacterial overgrowth, reduced bacterial translocation to remote organs, improved pancreas pathology, and reduced proinflammatory cytokine levels in plasma. Our current findings and future studies involving this uncharacterized bacterial phylotype will contribute to unraveling one of the potential mechanisms of probiotic therapy.
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279
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Liberatore AMA, Moreira FC, Gomes TAT, Menchaca-Diaz JL, Koh IHJ. Typical and atypical enteropathogenic Escherichia coli bacterial translocation associated with tissue hypoperfusion in rats. Braz J Med Biol Res 2011; 44:1018-24. [PMID: 21989977 DOI: 10.1590/s0100-879x2011007500105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 07/27/2011] [Indexed: 11/21/2022] Open
Abstract
Although enteropathogenic Escherichia coli (EPEC) are well-recognized diarrheal agents, their ability to translocate and cause extraintestinal alterations is not known. We investigated whether a typical EPEC (tEPEC) and an atypical EPEC (aEPEC) strain translocate and cause microcirculation injury under conditions of intestinal bacterial overgrowth. Bacterial translocation (BT) was induced in female Wistar-EPM rats (200-250 g) by oroduodenal catheterization and inoculation of 10 mL 10(10) colony forming unit (CFU)/mL, with the bacteria being confined between the duodenum and ileum with ligatures. After 2 h, mesenteric lymph nodes (MLN), liver and spleen were cultured for translocated bacteria and BT-related microcirculation changes were monitored in mesenteric and abdominal organs by intravital microscopy and laser Doppler flow, respectively. tEPEC (N = 11) and aEPEC (N = 11) were recovered from MLN (100%), spleen (36.4 and 45.5%), and liver (45.5 and 72.7%) of the animals, respectively. Recovery of the positive control E. coli R-6 (N = 6) was 100% for all compartments. Bacteria were not recovered from extraintestinal sites of controls inoculated with non-pathogenic E. coli strains HB101 (N = 6) and HS (N = 10), or saline. Mesenteric microcirculation injuries were detected with both EPEC strains, but only aEPEC was similar to E. coli R-6 with regard to systemic tissue hypoperfusion. In conclusion, overgrowth of certain aEPEC strains may lead to BT and impairment of the microcirculation in systemic organs.
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Affiliation(s)
- A M A Liberatore
- Departamento de Pediatria, Universidade Federal de São Paulo, São Paulo, SP, Brasil
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280
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Reino DC, Pisarenko V, Palange D, Doucet D, Bonitz RP, Lu Q, Colorado I, Sheth SU, Chandler B, Kannan KB, Ramanathan M, Xu DZ, Deitch EA, Feinman R. Trauma hemorrhagic shock-induced lung injury involves a gut-lymph-induced TLR4 pathway in mice. PLoS One 2011; 6:e14829. [PMID: 21829592 PMCID: PMC3150139 DOI: 10.1371/journal.pone.0014829] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Accepted: 06/16/2011] [Indexed: 12/17/2022] Open
Abstract
Background Injurious non-microbial factors released from the stressed gut during shocked states contribute to the development of acute lung injury (ALI) and multiple organ dysfunction syndrome (MODS). Since Toll-like receptors (TLR) act as sensors of tissue injury as well as microbial invasion and TLR4 signaling occurs in both sepsis and noninfectious models of ischemia/reperfusion (I/R) injury, we hypothesized that factors in the intestinal mesenteric lymph after trauma hemorrhagic shock (T/HS) mediate gut-induced lung injury via TLR4 activation. Methods/Principal Findings The concept that factors in T/HS lymph exiting the gut recreates ALI is evidenced by our findings that the infusion of porcine lymph, collected from animals subjected to global T/HS injury, into naïve wildtype (WT) mice induced lung injury. Using C3H/HeJ mice that harbor a TLR4 mutation, we found that TLR4 activation was necessary for the development of T/HS porcine lymph-induced lung injury as determined by Evan's blue dye (EBD) lung permeability and myeloperoxidase (MPO) levels as well as the induction of the injurious pulmonary iNOS response. TRIF and Myd88 deficiency fully and partially attenuated T/HS lymph-induced increases in lung permeability respectively. Additional studies in TLR2 deficient mice showed that TLR2 activation was not involved in the pathology of T/HS lymph-induced lung injury. Lastly, the lymph samples were devoid of bacteria, endotoxin and bacterial DNA and passage of lymph through an endotoxin removal column did not abrogate the ability of T/HS lymph to cause lung injury in naïve mice. Conclusions/Significance Our findings suggest that non-microbial factors in the intestinal mesenteric lymph after T/HS are capable of recreating T/HS-induced lung injury via TLR4 activation.
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Affiliation(s)
- Diego C. Reino
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Vadim Pisarenko
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - David Palange
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Danielle Doucet
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Robert P. Bonitz
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Qi Lu
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Iriana Colorado
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Sharvil U. Sheth
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Benjamin Chandler
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Kolenkode B. Kannan
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Madhuri Ramanathan
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Da Zhong Xu
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
| | - Edwin A. Deitch
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
- * E-mail: (RF); (EAD)
| | - Rena Feinman
- Department of Surgery, University of Medicine and Dentistry of New Jersey (UMDNJ)- New Jersey Medical School, Newark, New Jersey, United States of America
- * E-mail: (RF); (EAD)
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281
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Hayakawa M, Asahara T, Henzan N, Murakami H, Yamamoto H, Mukai N, Minami Y, Sugano M, Kubota N, Uegaki S, Kamoshida H, Sawamura A, Nomoto K, Gando S. Dramatic changes of the gut flora immediately after severe and sudden insults. Dig Dis Sci 2011; 56:2361-5. [PMID: 21384123 DOI: 10.1007/s10620-011-1649-3] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 02/14/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND The gut flora is crucially involved in host homeostasis. However, the changes in the gut flora during the early phase of a critical illness are unknown. AIMS We investigated the changes in the gut flora at an early phase of severe insult in critically ill patients. METHODS Fifteen patients who experienced a sudden and severe insult were studied, along with 12 healthy volunteers as the control group. Fecal samples were acquired from the subjects by swabs of the rectum within 6 h after admission to the emergency room (day 0). Samples were serially collected from patients until day 14. Samples were also collected from control subjects. RESULTS On day 0, total bacterial counts were decreased to one-thousandth the number of the control subjects, in particular, obligate anaerobes and Lactobacillus were significantly decreased. In addition, on day 0, the major short-chain fatty acids of the patients were significantly lower than those of the control subjects. The gut flora and the concentrations of major short-chain fatty acids did not recover to normal levels. In contrast, Enterococcus and Pseudomonas increased during the study period. CONCLUSIONS The gut flora in critically ill patients changed immediately after a severe insult. The concentrations of the three major short-chain fatty acids were immediately decreased in tandem with the destruction of the gut flora. The gut flora and the concentration of major short-chain fatty acids did not improve during the first 2 weeks after hospital admission. At the same time, the number of harmful bacteria gradually increased.
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Affiliation(s)
- Mineji Hayakawa
- Emergency and Critical Care Center, Hokkaido University Hospital, N14W5 Kita-ku, Sapporo, 060-8648, Japan.
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282
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A Fresh Look at the Process of Arriving at a Clinical Prognosis Part 2: Colic. J Equine Vet Sci 2011. [DOI: 10.1016/j.jevs.2011.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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283
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Dalfino L, Giglio MT, Puntillo F, Marucci M, Brienza N. Haemodynamic goal-directed therapy and postoperative infections: earlier is better. A systematic review and meta-analysis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2011; 15:R154. [PMID: 21702945 PMCID: PMC3219028 DOI: 10.1186/cc10284] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 05/23/2011] [Accepted: 06/24/2011] [Indexed: 12/17/2022]
Abstract
Introduction Infectious complications are the main causes of postoperative morbidity. The early timing of their promoting factors is the rationale for perioperative strategies attempting to reduce them. Our aim was to determine the effects of perioperative haemodynamic goal-directed therapy on postoperative infection rates. Methods We performed a systematic review and meta-analysis. MEDLINE, EMBASE, The Cochrane Library and the DARE databases were searched up to March 2011. Randomised, controlled trials of major surgery in adult patients managed with perioperative goal-directed therapy or according to routine haemodynamic practice were included. Primary outcome measure was specific type of infection. Results Twenty-six randomised, controlled trials with a combined total of 4,188 participants met our inclusion criteria. Perioperative goal-directed therapy significantly reduced surgical site infections (pooled OR 0.58, 95% CI 0.46 to 0.74; P < 0.0001), pneumonia (pooled OR 0.71, 95% CI 0.55 to 0.92; P = 0.009), and urinary tract infections (pooled OR 0.44, 95% CI 0.22 to 0.84; P = 0.02). A significant benefit was found regarding total infectious episodes (OR 0.40, 95% CI 0.28 to 0.58; P < 0.00001). Conclusions Flow-directed haemodynamic therapy designed to optimise oxygen delivery protects surgical patients against postoperative hospital-acquired infections and must be strongly encouraged, particularly in the high-risk surgical population.
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Affiliation(s)
- Lidia Dalfino
- Anesthesia and Intensive Care Unit, Department of Emergency and Organ Transplantation, University of Bari, Piazza G, Cesare 11, I-70124 Bari, Italy
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284
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White LE, Hassoun HT. Inflammatory Mechanisms of Organ Crosstalk during Ischemic Acute Kidney Injury. Int J Nephrol 2011; 2012:505197. [PMID: 21826270 PMCID: PMC3118535 DOI: 10.4061/2012/505197] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Accepted: 03/10/2011] [Indexed: 01/22/2023] Open
Abstract
Acute kidney injury (AKI) is a common complication during inpatient hospitalization, and clinical outcomes remain poor despite advancements in renal replacement therapy. AKI in the setting of multiple organ failure (MOF) remains a formidable challenge to clinicians and incurs an unacceptably high mortality rate. Kidney ischemia-reperfusion injury (IRI) incites a proinflammatory cascade and releases cellular and soluble mediators with systemic implications for remote organ injury. Evidence from preclinical models cites mechanisms of organ crosstalk during ischemic AKI including the expression of cellular adhesion molecules, lymphocyte trafficking, release of proinflammatory cytokines and chemokines, and modification of the host innate and adaptive immune response systems. In this paper, the influence of kidney IRI on systemic inflammation and distant organ injury will be examined. Recent experimental data and evolving concepts of organ crosstalk during ischemic AKI will also be discussed in detail.
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Affiliation(s)
- Laura E White
- Department of Surgery, The Methodist Hospital and Research Institute, Houston, TX 77030, USA
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285
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Kannan KB, Colorado I, Reino D, Palange D, Lu Q, Qin X, Abungu B, Watkins A, Caputo FJ, Xu DZ, Semenza GL, Deitch EA, Feinman R. Hypoxia-inducible factor plays a gut-injurious role in intestinal ischemia reperfusion injury. Am J Physiol Gastrointest Liver Physiol 2011; 300:G853-61. [PMID: 21183660 PMCID: PMC3094138 DOI: 10.1152/ajpgi.00459.2010] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gut injury and loss of normal intestinal barrier function are key elements in the paradigm of gut-origin systemic inflammatory response syndrome, acute lung injury, and multiple organ dysfunction syndrome (MODS). As hypoxia-inducible factor (HIF-1) is a critical determinant of the physiological and pathophysiological response to hypoxia and ischemia, we asked whether HIF-1 plays a proximal role in the induction of gut injury and subsequent lung injury. Using partially HIF-1α-deficient mice in an isolated superior mesenteric artery occlusion (SMAO) intestinal ischemia reperfusion (I/R) injury model (45 min SMAO followed by 3 h of reperfusion), we showed a direct relationship between HIF-1 activation and intestinal I/R injury. Specifically, partial HIF-1α deficiency attenuated SMAO-induced increases in intestinal permeability, lipid peroxidation, mucosal caspase-3 activity, and IL-1β mRNA levels. Furthermore, partial HIF-1α deficiency prevented the induction of ileal mucosal inducible nitric oxide synthase (iNOS) protein levels after SMAO and iNOS deficiency ameliorated SMAO-induced villus injury. Resistance to SMAO-induced gut injury was also associated with resistance to lung injury, as reflected by decreased levels of myeloperoxidase, IL-6 and IL-10 in the lungs of HIF-1α(+/-) mice. In contrast, a short duration of SMAO (15 min) followed by 3 h of reperfusion neither induced mucosal HIF-1α protein levels nor caused significant gut and lung injury in wild-type or HIF-1α(+/-) mice. This study indicates that intestinal HIF-1 activation is a proximal regulator of I/R-induced gut mucosal injury and gut-induced lung injury. However, the duration and severity of the gut I/R insult dictate whether HIF-1 plays a gut-protective or deleterious role.
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Affiliation(s)
- Kolenkode B. Kannan
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Iriana Colorado
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Diego Reino
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - David Palange
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Qi Lu
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Xiaofa Qin
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Billy Abungu
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Anthony Watkins
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Francis J. Caputo
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Da-Zhong Xu
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Gregg L. Semenza
- 2Vascular Program, Institute for Cell Engineering, and McKusick-Nathans Institute of Genetic Medicine, John Hopkins University School of Medicine, Baltimore, Maryland
| | - Edwin A. Deitch
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
| | - Rena Feinman
- 1Department of Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey; and
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286
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Macrophage-produced IL-12p70 mediates hemorrhage-induced damage in a complement-dependent manner. Shock 2011; 35:134-40. [PMID: 20577145 DOI: 10.1097/shk.0b013e3181ed8ec9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hemorrhage and hemorrhagic shock instigate intestinal damage and inflammation. Multiple components of the innate immune response, including complement and neutrophil infiltration, are implicated in this pathology. To investigate the interaction of complement activation and other components of the innate immune response during hemorrhage, we treated mice after hemorrhage with CR2-fH, a targeted inhibitor of the alternative complement pathway and assessed intestinal damage and inflammation 2 h after hemorrhage. In wild-type mice, CR2-fH attenuated hemorrhage-induced, midjejunal damage and inflammation as determined by decreased mucosal damage, macrophage infiltration, leukotriene B4, IL-12p40, and TNF-[alpha] production. The critical nature of intestinal macrophage infiltration and activation in the response to hemorrhage was further determined using mice pretreated with clodronate-containing liposomes. The absence of either macrophages or IL-12p70 attenuated intestinal damage. These data suggest that complement activation and macrophage infiltration with IL-12p70 production are critical to hemorrhage-induced midjejunal damage and inflammation.
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287
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Sonnier DI, Makley AT, Friend LAW, Bailey SR, Lentsch AB, Pritts TA. Hemorrhagic shock induces a proinflammatory milieu in the gut lumen. J Surg Res 2011; 170:272-9. [PMID: 21529836 DOI: 10.1016/j.jss.2011.03.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/11/2011] [Accepted: 03/03/2011] [Indexed: 12/25/2022]
Abstract
BACKGROUND Intestinal injury is a consequence of hemorrhagic shock and resuscitation. The intestinal mucosa has been shown to respond to ischemia/reperfusion injury with production of inflammatory mediators. Previous work in our laboratory indicates that intestinal epithelial cells secrete proinflammatory cytokines in the direction of both the lamina propria and intestinal lumen. The ability of the intestinal mucosa to transmit inflammatory signals into the gut lumen after hemorrhagic shock is unknown. We hypothesized that hemorrhagic shock results in secretion of proinflammatory cytokines into the gut lumen. METHODS Male C57/Bl6 mice underwent femoral artery cannulation and hemorrhage to a systolic blood pressure of 20 mmHg for 1 h, then resuscitation with lactated Ringer's (LR) solution. Sham animals were cannulated only. Mice were decannulated and sacrificed at intervals. Stool and succus were removed from intestinal segments, weighed, and placed into buffer solution. Specimens were analyzed via enzyme-linked immunosorbent assay (ELISA). RESULTS Compared with sham-injured mice, hemorrhagic shock resulted in increased intestinal luminal cytokines. At 3 h after injury, elevated levels of IL-6 were found in the cecal stool. At 6 h after injury, TNFα, IL-6, and MIP-2 were significantly elevated in the cecal stool, and IL-6 and MIP-2 were significantly elevated in the distal colonic stool. CONCLUSIONS Hemorrhagic shock results in secretion of proinflammatory cytokines into the intestinal lumen. These findings suggest that the intestinal mucosa may transmit and receive signals in a paracrine fashion via the gut lumen.
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Affiliation(s)
- Dennis I Sonnier
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
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288
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Derikx JPM, Luyer MDP, Heineman E, Buurman WA. Non-invasive markers of gut wall integrity in health and disease. World J Gastroenterol 2011. [PMID: 21072889 DOI: 10.3748/wjg.v16.i43.5272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The intestinal mucosa is responsible for the absorption of nutrients from the lumen and for the separation of the potentially toxic luminal content (external environment) from the host (internal environment). Disruption of this delicate balance at the mucosal interface is the basis for numerous (intestinal) diseases. Experimental animal studies have shown that gut wall integrity loss is involved in the development of various inflammatory syndromes, including post-operative or post-traumatic systemic inflammatory response syndrome, sepsis, and multiple organ failure. Assessment of gut wall integrity in clinical practice is still a challenge, as it is difficult to evaluate the condition of the gut non-invasively with currently available diagnostic tools. Moreover, non-invasive, rapid diagnostic means to assess intestinal condition are needed to evaluate the effects of treatment of intestinal disorders. This review provides a survey of non-invasive tests and newly identified markers that can be used to assess gut wall integrity.
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290
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Moore EE. Claude H. Organ, Jr. memorial lecture: splanchnic hypoperfusion provokes acute lung injury via a 5-lipoxygenase-dependent mechanism. Am J Surg 2011; 200:681-9. [PMID: 21146002 DOI: 10.1016/j.amjsurg.2010.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 05/31/2010] [Accepted: 05/31/2010] [Indexed: 01/01/2023]
Abstract
Postinjury multiple organ failure (MOF) is the net result of a dysfunctional immune response to injury characterized by a hyperactive innate system and a suppressed adaptive system. Acute lung injury (ALI) is the first clinical manifestation of organ failure, followed by renal and hepatic dysfunction. Circulatory shock is integral in the early pathogenesis of MOF, and the gut has been invoked as the motor of MOF. Mesenteric lymph is recognized as the mechanistic link between splanchnic ischemia/reperfusion and distant organ dysfunction, but the specific mediators remain to be defined. Current evidence suggests the lipid fraction of postshock mesenteric lymph is central in the etiology of ALI. Specifically, our recent work suggests that intestinal phospholipase A2 generated arachidonic acid and its subsequent 5-lipoxygenase products are essential in the pathogenesis of ALI. Proteins conveyed via postshock mesenteric lymph also may have an important role. Elucidating these mediators and the timing of their participation in pulmonary inflammation is critical in translating our current knowledge to new therapeutic strategies at the bedside.
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Affiliation(s)
- Ernest E Moore
- Department of Surgery, University of Colorado Denver, Denver, CO 80204, USA.
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291
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Ferrous iron is found in mesenteric lymph bound to TIMP-2 following hemorrhage/resuscitation. Biometals 2011; 24:279-89. [PMID: 21229381 DOI: 10.1007/s10534-010-9394-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Accepted: 12/01/2010] [Indexed: 01/06/2023]
Abstract
Extracellular iron has been implicated in the pathogenesis of post-injury organ failure. However, the source(s) and biochemical species of this iron have not been identified. Based upon evidence that distant organ injury results from an increase in intestinal permeability, we looked for ferrous iron in mesenteric lymph in anesthetized rats undergoing hemorrhage and fluid resuscitation (H/R). Ferrous iron increased in lymph from 4.7 nmol/mg of protein prior to hemorrhage to 86.6 nmol/mg during resuscitation. Utilizing immuno-spin trapping in protein fractions that were rich in iron, we tentatively indentified protein carrier(s) of ferrous iron by MALDI-TOF MS. One of the identified proteins was the metalloproteinase (MMP) inhibitor, TIMP-2. Antibody to TIMP-2 immunoprecipitated 74% of the ferrozine detectable iron in its protein fraction. TIMP-2 binds iron in vitro at pH 6.3, which is typical of conditions in the mesentery during hemorrhage, but it retains the ability to inhibit the metalloproteases MMP-2 and MMP-9. In summary, there is a large increase in extracellular ferrous iron in the gut in H/R demonstrating dysregulation of iron homeostasis. We have identified, for the first time, the binding of extracellular iron to TIMP-2.
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292
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Königsrainer I, Türck MH, Eisner F, Meile T, Hoffmann J, Küper M, Zieker D, Glatzle J. The Gut is not only the Target but a Source of Inflammatory Mediators Inhibiting Gastrointestinal Motility During Sepsis. Cell Physiol Biochem 2011; 28:753-60. [DOI: 10.1159/000335769] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2011] [Indexed: 11/19/2022] Open
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293
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Shimizu K, Ogura H, Tomono K, Tasaki O, Asahara T, Nomoto K, Morotomi M, Matsushima A, Nakahori Y, Yamano S, Osuka A, Kuwagata Y, Sugimoto H. Patterns of Gram-stained fecal flora as a quick diagnostic marker in patients with severe SIRS. Dig Dis Sci 2011; 56:1782-8. [PMID: 21107910 PMCID: PMC3097348 DOI: 10.1007/s10620-010-1486-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 11/04/2010] [Indexed: 02/06/2023]
Abstract
BACKGROUND The gut is an important target organ of injury during critically ill conditions. Although Gram staining is a common and quick method for identifying bacteria, its clinical application has not been fully evaluated in critically ill conditions. AIMS This study's aims were to identify patterns of Gram-stained fecal flora and compare them to cultured bacterial counts and to investigate the association between the patterns and septic complications in patients with severe systemic inflammatory response syndrome (SIRS). METHODS Fifty-two patients with SIRS were included whose Gram-stained fecal flora was classified into three patterns. In a diverse pattern, large numbers of multiple kinds of bacteria completely covered the field. In a single pattern, one specific kind of bacteria or fungi predominantly covered the field. In a depleted pattern, most bacteria were diminished in the field. RESULTS In the analysis of fecal flora, the numbers of total obligate anaerobes in the depleted pattern was significantly lower than those in the diverse pattern and single pattern (p < 0.05). The concentrations of total organic acids, acetic acid, and propionic acid in the depleted pattern were significantly lower than those in diverse pattern and single pattern (p < 0.05). Mortality due to multiple organ dysfunction syndrome for the single pattern (52%) and the depleted pattern (64%) was significantly higher than that for the diverse pattern (6%) (p < 0.05). CONCLUSIONS Gram-stained fecal flora can be classified into three patterns and are associated with both cultured bacterial counts and clinical information. Gram-stained fecal bacteria can be used as a quick bedside diagnostic marker for severe SIRS patients.
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Affiliation(s)
- Kentaro Shimizu
- Department of Clinical Quality Management, Osaka University Hospital, Osaka, Japan.
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294
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White LE, Chaudhary R, Moore LJ, Moore FA, Hassoun HT. Surgical sepsis and organ crosstalk: the role of the kidney. J Surg Res 2010; 167:306-15. [PMID: 21324390 DOI: 10.1016/j.jss.2010.11.923] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 11/19/2010] [Accepted: 11/29/2010] [Indexed: 02/06/2023]
Abstract
Acute kidney injury (AKI) is a common complication of hospitalized patients, and clinical outcomes remain poor despite advances in renal replacement therapy. The accepted pathophysiology of AKI in the setting of sepsis has evolved from one of simple decreased renal blood flow to one that involves a more complex interaction of intra-glomerular microcirculatory vasodilation combined with the local release of inflammatory mediators and apoptosis. Evidence from preclinical AKI models suggests that crosstalk occurs between kidneys and other organ systems via soluble and cellular inflammatory mediators and that this involves both the innate and adaptive immune systems. These interactions are reflected by genomic changes and abnormal rates of cellular apoptosis in distant organs including the lungs, heart, gut, liver, and central nervous system. The purpose of this article is to review the influence of AKI, particularly sepsis-associated AKI, on inter-organ crosstalk in the context of systemic inflammation and multiple organ failure (MOF).
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Affiliation(s)
- Laura E White
- Department of Surgery, The Methodist Hospital and Research Institute, Houston Texas, USA
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295
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Intestinal flora imbalance results in altered bacterial translocation and liver function in rats with experimental cirrhosis. Eur J Gastroenterol Hepatol 2010; 22:1481-6. [PMID: 20739895 DOI: 10.1097/meg.0b013e32833eb8b0] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND/PURPOSE The intestinal microflora plays a major role in human health. Intestinal flora imbalances are seen in clinical settings, such as cirrhosis, in which bacterial translocation (BT) results in migration of bacteria or bacterial products from the intestinal lumen to extraintestinal sites. In this study, we explored the effect of alterations in gut flora on BT and liver function in cirrhotic rats. METHODS In this study, we used a carbon tetrachloride-induced cirrhotic rat model to compare the abundance of major aerobic and anaerobic bacterial species in healthy and cirrhotic rats. We used antibiotic (norfloxacin) and different probiotic treatments to change the status of gut flora in the cirrhotic rats and evaluated BT, liver function, and endotoxemia in the different models. RESULTS We found higher levels of Enterobacteriaceae in cirrhotic rats when compared with healthy rats. Bifidobacteria treatment resulted in lower levels of Enterobacteriaceae along with increased levels of Lactobacillus when compared with the normal saline group. Both Bifidobacteria and Enterococcus treatments resulted in lower endotoxin levels than in the normal saline group. CONCLUSION Gut flora imbalances in cirrhotic rats result in significant changes in BT and liver function in cirrhotic rats.
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296
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Derikx JPM, Luyer MDP, Heineman E, Buurman WA. Non-invasive markers of gut wall integrity in health and disease. World J Gastroenterol 2010; 16:5272-9. [PMID: 21072889 PMCID: PMC2980675 DOI: 10.3748/wjg.v16.i42.5272] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The intestinal mucosa is responsible for the absorption of nutrients from the lumen and for the separation of the potentially toxic luminal content (external environment) from the host (internal environment). Disruption of this delicate balance at the mucosal interface is the basis for numerous (intestinal) diseases. Experimental animal studies have shown that gut wall integrity loss is involved in the development of various inflammatory syndromes, including post-operative or post-traumatic systemic inflammatory response syndrome, sepsis, and multiple organ failure. Assessment of gut wall integrity in clinical practice is still a challenge, as it is difficult to evaluate the condition of the gut non-invasively with currently available diagnostic tools. Moreover, non-invasive, rapid diagnostic means to assess intestinal condition are needed to evaluate the effects of treatment of intestinal disorders. This review provides a survey of non-invasive tests and newly identified markers that can be used to assess gut wall integrity.
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297
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Hoffman SM, Wang H, Pope MR, Fleming SD. Helicobacter infection alters MyD88 and Trif signalling in response to intestinal ischaemia-reperfusion. Exp Physiol 2010; 96:104-13. [PMID: 21056969 DOI: 10.1113/expphysiol.2010.055426] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ischaemia-reperfusion-induced intestinal injury requires both Toll-like receptor 4 (TLR4) signalling through myeloid differentiation primary response gene (88) (MyD88) and complement activation. As a common Gram-negative intestinal pathogen, Helicobacter hepaticus signals through TLR4 and upregulates the complement inhibitor, decay accelerating factor (DAF; CD55). Since ischaemia-reperfusion (IR) injury is complement dependent, we hypothesized that Helicobacter infection may alter IR-induced intestinal damage. Infection increased DAF transcription and subsequently decreased complement activation in response to IR without altering intestinal damage in wild-type mice. Ischaemia-reperfusion induced similar levels of DAF mRNA expression in uninfected wild-type, MyD88(-/-) or TIR-domain-containing adaptor-inducing interferon-β (Trif)-deficient mice. However, during infection, IR-induced DAF transcription was significantly attenuated in Trif-deficient mice. Likewise, IR-induced intestinal damage, complement component 3 deposition and prostaglandin E(2) production were attenuated in Helicobacter-infected, Trif-deficient but not MyD88(-/-) mice. While infection attenuated IR-induced cytokine production in wild-type and MyD88(-/-) mice, there was no further decrease in Trif-deficient mice. These data indicate distinct roles for MyD88 and Trif in IR-induced inflammation and suggest that chronic, undetected infections, such as Helicobacter, alter the use of the adaptor proteins to induce damage.
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Affiliation(s)
- Sara M Hoffman
- Kansas State University, Division of Biology, Manhattan, KS 66506, USA
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298
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Zhang Q, Piao XL, Piao XS, Lu T, Wang D, Kim SW. Preventive effect of Coptis chinensis and berberine on intestinal injury in rats challenged with lipopolysaccharides. Food Chem Toxicol 2010; 49:61-9. [PMID: 20932871 DOI: 10.1016/j.fct.2010.09.032] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 09/09/2010] [Accepted: 09/29/2010] [Indexed: 02/03/2023]
Abstract
Coptis chinensis has been used in traditional Chinese medicine to treat inflammatory symptoms. Berberine is the main alkaloid compound of C. chinensis. This study utilized a typical lipopolysaccharide (LPS) injured model to investigate the effects of C. chinensis aqueous extract (CCAE) and berberine (major active ingredient in CCAE) in the gut-derived sepsis. In rats, pretreatment with different doses of berberine (30 or 120 mg/kg bw, i.g.; BBR30 or BBR120) or CCAE (containing 9.9% berberine; 300 mg/kg bw, i.g.; CCAE300) prior to the administration of LPS (20 mg/kg bw, i.p.) significantly suppressed the increased tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and nitrite oxide (NO) in plasma as well as the activation of toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) in ileum. In addition, CCAE300 and BBR30 markedly elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px); significantly prevented the increased malondialdehyde (MDA), NO and villi injury in ileum compared with the negative control. Collectively, CCAE300 and BBR30 reduced the LPS-induced intestinal damage by elevating the activities of SOD and GSH-Px and by suppressing the activation of TLR4 and NF-κB in ileum. These results indicate that CCAE and berberine are promising agents for preventing sepsis and its complications.
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Affiliation(s)
- Qian Zhang
- State Key Laboratory of Animal Nutrition, China Agricultural University, Beijing, China
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299
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Sonnier DI, Bailey SR, Schuster RM, Lentsch AB, Pritts TA. TNF-α induces vectorial secretion of IL-8 in Caco-2 cells. J Gastrointest Surg 2010; 14:1592-9. [PMID: 20827577 PMCID: PMC4624195 DOI: 10.1007/s11605-010-1321-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 08/09/2010] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Intestinal epithelial cells represent an important component of innate immunity, with sophisticated responses to inflammatory stimuli. The manner in which intestinal epithelial cell polarity affects responses to inflammatory stimuli is largely unknown. We hypothesized that polarized intestinal epithelial cells exhibit a bidirectional inflammatory response dependent upon the location of the stimulus. METHODS Caco-2 cells were grown on semi-permeable inserts in a dual-compartment culture system and treated with tumor necrosis factor-α (TNF-α; 100 ng/ml) or serum-free media in the apical or basolateral chamber. Interleukin-8 (IL-8) production in each chamber was measured by enzyme-linked immunosorbent assay. To determine receptor specificity, anti-TNF receptor antibodies were added to the apical or basolateral chamber. RESULTS Basolateral stimulation with TNF-α resulted in increased apical and basolateral IL-8 production. Apical TNF-α stimulation resulted in increased apical, but not basolateral IL-8 production. Receptor blockade suggested TNF receptor 1 involvement on both apical and basolateral membranes, while TNF receptor 2 was only active on the apical membrane. CONCLUSION Polarized intestinal epithelial cells respond to TNF-α stimulation with focused, directional secretion of the proinflammatory cytokine IL-8. These findings are important because they suggest that intestinal epithelial cells are capable of organizing their response to inflammatory signals and producing inflammatory mediators in a bidirectional, vectorial fashion.
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Affiliation(s)
- Dennis I Sonnier
- Department of Surgery, University of Cincinnati College of Medicine, Mail Location 0558, 231 Albert Sabin Way, Cincinnati, OH 45267, USA.
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300
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Feinman R, Deitch EA, Watkins AC, Abungu B, Colorado I, Kannan KB, Sheth SU, Caputo FJ, Lu Q, Ramanathan M, Attan S, Badami CD, Doucet D, Barlos D, Bosch-Marce M, Semenza GL, Xu DZ. HIF-1 mediates pathogenic inflammatory responses to intestinal ischemia-reperfusion injury. Am J Physiol Gastrointest Liver Physiol 2010; 299:G833-43. [PMID: 20689059 PMCID: PMC2957330 DOI: 10.1152/ajpgi.00065.2010] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 07/27/2010] [Indexed: 01/31/2023]
Abstract
Acute lung injury (ALI) and the development of the multiple organ dysfunction syndrome (MODS) are major causes of death in trauma patients. Gut inflammation and loss of gut barrier function as a consequence of splanchnic ischemia-reperfusion (I/R) have been implicated as the initial triggering events that contribute to the development of the systemic inflammatory response, ALI, and MODS. Since hypoxia-inducible factor (HIF-1) is a key regulator of the physiological and pathophysiological response to hypoxia, we asked whether HIF-1 plays a proximal role in the induction of gut injury and subsequent lung injury. Utilizing partially HIF-1α-deficient mice in a global trauma hemorrhagic shock (T/HS) model, we found that HIF-1 activation was necessary for the development of gut injury and that the prevention of gut injury was associated with an abrogation of lung injury. Specifically, in vivo studies demonstrated that partial HIF-1α deficiency ameliorated T/HS-induced increases in intestinal permeability, bacterial translocation, and caspase-3 activation. Lastly, partial HIF-1α deficiency reduced TNF-α, IL-1β, cyclooxygenase-2, and inducible nitric oxide synthase levels in the ileal mucosa after T/HS whereas IL-1β mRNA levels were reduced in the lung after T/HS. This study indicates that prolonged intestinal HIF-1 activation is a proximal regulator of I/R-induced gut mucosal injury and gut-induced lung injury. Consequently, these results provide unique information on the initiating events in trauma-hemorrhagic shock-induced ALI and MODS as well as potential therapeutic insights.
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Affiliation(s)
- Rena Feinman
- UMDNJ-New Jersey Medical School, Dept. of Surgery, Newark, 07103, USA.
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