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Van Looveren K, Libert C. Should we target TNF receptors in the intestinal epithelium with glucocorticoids during systemic inflammation? Expert Opin Ther Targets 2018; 22:1029-1037. [DOI: 10.1080/14728222.2018.1539078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Kelly Van Looveren
- VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Claude Libert
- VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
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152
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Opportunities and Challenges for Single-Unit Recordings from Enteric Neurons in Awake Animals. MICROMACHINES 2018; 9:mi9090428. [PMID: 30424361 PMCID: PMC6187697 DOI: 10.3390/mi9090428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 08/17/2018] [Accepted: 08/23/2018] [Indexed: 12/18/2022]
Abstract
Advanced electrode designs have made single-unit neural recordings commonplace in modern neuroscience research. However, single-unit resolution remains out of reach for the intrinsic neurons of the gastrointestinal system. Single-unit recordings of the enteric (gut) nervous system have been conducted in anesthetized animal models and excised tissue, but there is a large physiological gap between awake and anesthetized animals, particularly for the enteric nervous system. Here, we describe the opportunity for advancing enteric neuroscience offered by single-unit recording capabilities in awake animals. We highlight the primary challenges to microelectrodes in the gastrointestinal system including structural, physiological, and signal quality challenges, and we provide design criteria recommendations for enteric microelectrodes.
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153
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McCall CE, Zabalawi M, Liu T, Martin A, Long DL, Buechler NL, Arts RJW, Netea M, Yoza BK, Stacpoole PW, Vachharajani V. Pyruvate dehydrogenase complex stimulation promotes immunometabolic homeostasis and sepsis survival. JCI Insight 2018; 3:99292. [PMID: 30089711 PMCID: PMC6129136 DOI: 10.1172/jci.insight.99292] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/21/2018] [Indexed: 12/22/2022] Open
Abstract
Limited understanding of the mechanisms responsible for life-threatening organ and immune failure hampers scientists' ability to design sepsis treatments. Pyruvate dehydrogenase kinase 1 (PDK1) is persistently expressed in immune-tolerant monocytes of septic mice and humans and deactivates mitochondrial pyruvate dehydrogenase complex (PDC), the gate-keeping enzyme for glucose oxidation. Here, we show that targeting PDK with its prototypic inhibitor dichloroacetate (DCA) reactivates PDC; increases mitochondrial oxidative bioenergetics in isolated hepatocytes and splenocytes; promotes vascular, immune, and organ homeostasis; accelerates bacterial clearance; and increases survival. These results indicate that the PDC/PDK axis is a druggable mitochondrial target for promoting immunometabolic and organ homeostasis during sepsis.
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Affiliation(s)
| | | | - Tiefu Liu
- Department of Internal Medicine/Molecular Medicine and
| | - Ayana Martin
- Department of Internal Medicine/Molecular Medicine and
| | - David L. Long
- Department of Internal Medicine/Molecular Medicine and
| | - Nancy L. Buechler
- Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Rob J. W. Arts
- Department in Internal Medicine and Radboud Center for Infectious Diseases, Radboud Medical Center, Nijmegen, Netherlands
| | - Mihai Netea
- Department in Internal Medicine and Radboud Center for Infectious Diseases, Radboud Medical Center, Nijmegen, Netherlands
| | - Barbara K. Yoza
- Department of Surgery/General Surgery and Trauma, Wake Forest Medical School, Winston- Salem, North Carolina, USA
| | - Peter W. Stacpoole
- Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, and Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Vidula Vachharajani
- Department of Internal Medicine/Molecular Medicine and
- Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
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154
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Mandal P, Feng Y, Lyons JD, Berger SB, Otani S, DeLaney A, Tharp GK, Maner-Smith K, Burd EM, Schaeffer M, Hoffman S, Capriotti C, Roback L, Young CB, Liang Z, Ortlund EA, DiPaolo NC, Bosinger S, Bertin J, Gough PJ, Brodsky IE, Coopersmith CM, Shayakhmetov DM, Mocarski ES. Caspase-8 Collaborates with Caspase-11 to Drive Tissue Damage and Execution of Endotoxic Shock. Immunity 2018; 49:42-55.e6. [PMID: 30021146 PMCID: PMC6064639 DOI: 10.1016/j.immuni.2018.06.011] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/25/2018] [Accepted: 06/21/2018] [Indexed: 11/18/2022]
Abstract
The execution of shock following high dose E. coli lipopolysaccharide (LPS) or bacterial sepsis in mice required pro-apoptotic caspase-8 in addition to pro-pyroptotic caspase-11 and gasdermin D. Hematopoietic cells produced MyD88- and TRIF-dependent inflammatory cytokines sufficient to initiate shock without any contribution from caspase-8 or caspase-11. Both proteases had to be present to support tumor necrosis factor- and interferon-β-dependent tissue injury first observed in the small intestine and later in spleen and thymus. Caspase-11 enhanced the activation of caspase-8 and extrinsic cell death machinery within the lower small intestine. Neither caspase-8 nor caspase-11 was individually sufficient for shock. Both caspases collaborated to amplify inflammatory signals associated with tissue damage. Therefore, combined pyroptotic and apoptotic signaling mediated endotoxemia independently of RIPK1 kinase activity and RIPK3 function. These observations bring to light the relevance of tissue compartmentalization to disease processes in vivo where cytokines act in parallel to execute diverse cell death pathways.
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Affiliation(s)
- Pratyusha Mandal
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta GA 30322, USA.
| | - Yanjun Feng
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | - John D Lyons
- Department of Surgery, Emory Critical Care Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Scott B Berger
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA; Host Defense Discovery Performance Unit, Infectious Disease Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Shunsuke Otani
- Department of Surgery, Emory Critical Care Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Alexandra DeLaney
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Gregory K Tharp
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - Kristal Maner-Smith
- Department of Biochemistry, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Eileen M Burd
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Michelle Schaeffer
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Sandra Hoffman
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA; Host Defense Discovery Performance Unit, Infectious Disease Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Carol Capriotti
- Host Defense Discovery Performance Unit, Infectious Disease Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Linda Roback
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Cedrick B Young
- Lowance Center for Human Immunology, Emory University, Atlanta GA 30322, USA
| | - Zhe Liang
- Department of Surgery, Emory Critical Care Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Nelson C DiPaolo
- Lowance Center for Human Immunology, Emory University, Atlanta GA 30322, USA
| | - Steven Bosinger
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - John Bertin
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Peter J Gough
- Pattern Recognition Receptor Discovery Performance Unit, Immuno-Inflammation Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA; Host Defense Discovery Performance Unit, Infectious Disease Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Igor E Brodsky
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Craig M Coopersmith
- Department of Surgery, Emory Critical Care Center, Emory University School of Medicine, Atlanta GA 30322, USA
| | | | - Edward S Mocarski
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta GA 30322, USA.
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155
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He S, Guo Y, Zhao J, Xu X, Song J, Wang N, Liu Q. Ferulic acid protects against heat stress-induced intestinal epithelial barrier dysfunction in IEC-6 cells via the PI3K/Akt-mediated Nrf2/HO-1 signaling pathway. Int J Hyperthermia 2018; 35:112-121. [PMID: 30010455 DOI: 10.1080/02656736.2018.1483534] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE Intestinal epithelial barrier dysfunction is crucial in the pathogenesis of intestinal and systemic diseases. Ferulic acid (FA) possesses promising antioxidant activities. In a previous study, we demonstrated potentially protective effects of FA against heat stress-induced intestinal epithelial barrier dysfunction in IEC-6 cells. However, the underlying mechanisms are unclear. The present study aimed to elucidate whether FA protects IEC-6 cells from heat stress-induced intestinal epithelial barrier dysfunction via antioxidative mechanisms. MATERIALS AND METHODS IEC-6 cells were pretreated with FA prior to hyperthermia exposure at 42 °C for 6 h, and the levels of intracellular reactive oxygen species (ROS), malondialdehyde (MDA), nitrogen oxide (NO), and superoxide dismutase (SOD) activity were analyzed. The intestinal epithelial barrier function was determined by transepithelial electrical resistance (TER) values and 4-kDa fluorescein isothiocyanate-dextran (FD4) flux in IEC-6 cell monolayers. Expression of related proteins was detected by Western blotting. RESULTS FA suppressed heat stress-induced intestinal oxidative stress damage by reducing ROS, MDA and NO production, while enhancing SOD activity. Furthermore, FA treatment strengthened intestinal barrier function via increasing the phosphorylation levels of Akt, nuclear factor-erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) protein expression, which was reversed by zinc protoporphyrin (an HO-1 inhibitor). Additionally, LY294002, a specific PI3K/Akt inhibitor, significantly suppressed FA-induced Nrf2 nuclear translocation and HO-1 protein expression and inhibited FA-induced occludin and ZO-1 protein expression. CONCLUSIONS FA protected against heat stress-induced intestinal epithelial barrier dysfunction via activating the PI3K/Akt-mediated Nrf2/HO-1 signaling pathway in IEC-6 cells.
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Affiliation(s)
- Shasha He
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China.,c Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases , Beijing , P. R. China
| | - Yuhong Guo
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China.,c Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases , Beijing , P. R. China
| | - Jingxia Zhao
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China.,c Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases , Beijing , P. R. China
| | - Xiaolong Xu
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China.,c Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases , Beijing , P. R. China
| | - Jin Song
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China
| | - Ning Wang
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China
| | - Qingquan Liu
- a Beijing Hospital of Traditional Chinese Medicine, Affiliated with Capital Medical University , Beijing , P. R. China.,b Beijing Institute of Traditional Chinese Medicine , Beijing , P. R. China.,c Beijing Key Laboratory of Basic Research with Traditional Chinese Medicine on Infectious Diseases , Beijing , P. R. China
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156
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Li Z, Gao M, Yang B, Zhang H, Wang K, Liu Z, Xiao X, Yang M. Naringin attenuates MLC phosphorylation and NF-κB activation to protect sepsis-induced intestinal injury via RhoA/ROCK pathway. Biomed Pharmacother 2018; 103:50-58. [PMID: 29635128 DOI: 10.1016/j.biopha.2018.03.163] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 03/16/2018] [Accepted: 03/28/2018] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Sepsis is commonly associated with excessive stimulation of host immune system and result in multi-organ failure dysfunction. Naringin has been reported to exhibit a variety of biological effects. The present study aimed to investigate the protective effect of naringin on sepsis-induced injury of intestinal barrier function in vivo and in vitro. METHODS Mice were randomly divided into 4 groups named sham (n = 20), CLP + vehicle (n = 20), CLP + NG (30 mg/kg) (n = 20) and CLP + NG (60 mg/kg) (n = 20) groups. Sepsis was induced by cecal ligation and puncture (CLP). H&E staining and transmission electron microscopy (TEM) were performed to observe intestinal mucosal morphology. ELISA was used to determine the intestinal permeability and inflammatory response in vivo and in vitro. Western blot and RhoA activity assay were performed to determine the levels of tight junction proteins and the activation of indicated signaling pathways. MTT assay was used to determine cell viability. RESULTS Naringin improved survival rate of CLP mice and alleviated sepsis-induced intestinal mucosal injury. Furthermore, naringin improved impaired intestinal permeability and inhibited the release of TNF-α and IL-6, while increased IL-10 level in CLP mice and lipopolysaccharide (LPS)-stimulated MODE-K cells in a dose-dependent manner. Naringin increased the expression of tight junction proteins ZO-1 and claudin-1 via RhoA/ROCK/NF-κB/MLCK/MLC signaling pathway in vivo and in vitro. CONCLUSION Naringin improved sepsis-induced intestinal injury via RhoA/ROCK/NF-κB/MLCK/MLC signaling pathway in vivo and in vitro.
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Affiliation(s)
- Zhiling Li
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Ming Gao
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Bingchang Yang
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Huali Zhang
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Kangkai Wang
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Zuoliang Liu
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China
| | - Xianzhong Xiao
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China.
| | - Mingshi Yang
- Translational Medicine Center of Sepsis, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Department of Critical Care Medicine, The Third Xiangya Hospital, Central South University, Changsha, 410013, People's Republic of China; Laboratory of Shock, Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, 410078, People's Republic of China.
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157
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Epidermal Growth Factor Improves Intestinal Integrity and Survival in Murine Sepsis Following Chronic Alcohol Ingestion. Shock 2018; 47:184-192. [PMID: 27465753 DOI: 10.1097/shk.0000000000000709] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Epidermal growth factor (EGF) is a cytoprotective protein that improves survival in preclinical models of sepsis through its beneficial effects on intestinal integrity. Alcohol use disorder worsens intestinal integrity and is associated with increased morbidity and mortality in critical illness. We sought to determine whether chronic alcohol ingestion alters the host response to systemic administration of EGF in sepsis. Six-week-old FVB/N mice were randomized to receive 20% alcohol or water for 12 weeks. All mice then underwent cecal ligation and puncture to induce polymicrobial sepsis. Mice were then randomized to receive either intraperitoneal injection of EGF (150 μg/kg/day) or normal saline. Water-fed mice given EGF had decreased 7-day mortality compared with water-fed mice (18% vs. 55%). Alcohol-fed mice given EGF also had decreased 7-day mortality compared with alcohol-fed mice (48% vs. 79%). Notably, while systemic EGF improved absolute survival to a similar degree in both water-fed and alcohol-fed mice, mortality was significantly higher in alcohol+EGF mice compared with water+EGF mice. Compared with water-fed septic mice, alcohol-fed septic mice had worsened intestinal integrity with intestinal hyperpermeability, increased intestinal epithelial apoptosis, decreased proliferation and shorter villus length. Systemic administration of EGF to septic alcohol-fed mice decreased intestinal permeability compared with septic alcohol-fed mice given vehicle, with increased levels of the tight junction mediators claudin-5 and JAM-A. Systemic administration of EGF to septic alcohol-fed mice also decreased intestinal apoptosis with an improvement in the Bax/Bcl-2 ratio. EGF also improved both crypt proliferation and villus length in septic alcohol-fed mice. EGF administration resulted in lower levels of both pro- and anti-inflammatory cytokines monocyte chemoattractant protein-1, tumor necrosis factor, and interleukin 10 in alcohol-fed mice. EGF is therefore effective at improving both intestinal integrity and mortality following sepsis in mice with chronic alcohol ingestion. However, the efficacy of EGF in sepsis is blunted in the setting of chronic alcohol ingestion, as intestinal integrity and mortality in alcohol-fed mice given EGF improves animals to levels seen in water-fed mice given vehicle but does not approach levels seen in water-fed mice given EGF.
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158
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Propofol Does Not Reduce Pyroptosis of Enterocytes and Intestinal Epithelial Injury After Lipopolysaccharide Challenge. Dig Dis Sci 2018; 63:81-91. [PMID: 29063417 DOI: 10.1007/s10620-017-4801-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 10/10/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND To date, mechanisms of sepsis-induced intestinal epithelial injury are not well known. P2X7 receptor (P2X7R) regulates pyroptosis of lymphocytes, and propofol is usually used for sedation in septic patients. AIMS We aimed to determine the occurrence of enterocyte pyroptosis mediated by P2X7R and to explore the effects of propofol on pyroptosis and intestinal epithelial injury after lipopolysaccharide (LPS) challenge. METHODS A novel regimen of LPS challenge was applied in vitro and in vivo. Inhibitors of P2X7R (A438079) and NLRP3 inflammasome (MCC950), and different doses of propofol were administered. The caspase-1 expression, caspase-3 expression, caspase-11 expression, P2X7R expression and NLRP3 expression, extracellular ATP concentration and YO-PRO-1 uptake, and cytotoxicity and HMGB1 concentration were detected to evaluate enterocyte pyroptosis in cultured cells and intestinal epithelial tissues. Chiu's score, diamine oxidase and villus length were used to evaluate intestinal epithelial injury. Moreover, survival analysis was performed. RESULTS LPS challenge activated caspase-11 expression and P2X7R expression, enhanced ATP concentration and YO-PRO-1 uptake, and led to increased cytotoxicity and HMGB1 concentration. Subsequently, LPS resulted in intestinal epithelial damage, as evidenced by increased levels of Chiu's score and diamine oxidase, and shorter villus length and high mortality of animals. A438079, but not MCC950, significantly relieved LPS-induced enterocyte pyroptosis and intestinal epithelial injury. Importantly, propofol did not confer the protective effects on enterocyte pyroptosis and intestinal epithelia although it markedly decreased P2X7R expression. CONCLUSION LPS attack leads to activation of caspase-11/P2X7R and pyroptosis of enterocytes. Propofol does not reduce LPS-induced pyroptosis and intestinal epithelial injury, although it inhibits P2X7R upregulation.
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159
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Mechanistic insights into the protective impact of zinc on sepsis. Cytokine Growth Factor Rev 2017; 39:92-101. [PMID: 29279185 DOI: 10.1016/j.cytogfr.2017.12.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 12/19/2017] [Indexed: 12/11/2022]
Abstract
Sepsis, a systemic inflammation as a response to a bacterial infection, is a huge unmet medical need. Data accumulated over the last decade suggest that the nutritional status of patients as well as composition of their gut microbiome, are strongly linked with the risk to develop sepsis, the severity of the disease and prognosis. In particular, the essential micronutrient zinc is essential in the resistance against sepsis and has shown to be protective in animal models as well as in human patients. The potential mechanisms by which zinc protects in sepsis are discussed in this review paper: we will focus on the inflammatory response, chemotaxis, phagocytosis, immune response, oxidative stress and modulation of the microbiome. A full understanding of the mechanism of action of zinc may open new preventive and therapeutic interventions in sepsis.
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160
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Lyons JD, Klingensmith NJ, Otani S, Mittal R, Liang Z, Ford ML, Coopersmith CM. Sepsis reveals compartment-specific responses in intestinal proliferation and apoptosis in transgenic mice whose enterocytes re-enter the cell cycle. FASEB J 2017; 31:5507-5519. [PMID: 28842422 PMCID: PMC5690387 DOI: 10.1096/fj.201700015rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 08/07/2017] [Indexed: 02/07/2023]
Abstract
Cell production and death are tightly regulated in the rapidly renewing gut epithelium, with proliferation confined to crypts and apoptosis occurring in villi and crypts. This study sought to determine how stress alters these compartmentalized processes. Wild-type mice made septic via cecal ligation and puncture had decreased crypt proliferation and increased crypt and villus apoptosis. Fabpi-TAg mice expressing large T-antigen solely in villi had ectopic enterocyte proliferation with increased villus apoptosis in unmanipulated animals. Septic fabpi-TAg mice had an unexpected increase in villus proliferation compared with unmanipulated littermates, whereas crypt proliferation was decreased. Cell cycle regulators cyclin D1 and cyclin D2 were decreased in jejunal tissue in septic transgenic mice. In contrast, villus and crypt apoptosis were increased in septic fabpi-TAg mice. To examine the relationship between apoptosis and proliferation in a compartment-specific manner, fabpi-TAg mice were crossed with fabpl-Bcl-2 mice, resulting in expression of both genes in the villus but Bcl-2 alone in the crypt. Septic bi-transgenic animals had decreased crypt apoptosis but had a paradoxical increase in villus apoptosis compared with septic fabpi-TAg mice, associated with decreased proliferation in both compartments. Thus, sepsis unmasks compartment-specific proliferative and apoptotic regulation that is not present under homeostatic conditions.-Lyons, J. D., Klingensmith, N. J., Otani, S., Mittal, R., Liang, Z., Ford, M. L., Coopersmith, C. M. Sepsis reveals compartment-specific responses in intestinal proliferation and apoptosis in transgenic mice whose enterocytes re-enter the cell cycle.
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Affiliation(s)
- John D Lyons
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Nathan J Klingensmith
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Shunsuke Otani
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
- Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Rohit Mittal
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Zhe Liang
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mandy L Ford
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Transplant Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Craig M Coopersmith
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, USA;
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, Georgia, USA
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161
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Evaluation of gut-blood barrier dysfunction in various models of trauma, hemorrhagic shock, and burn injury. J Trauma Acute Care Surg 2017; 83:944-953. [DOI: 10.1097/ta.0000000000001654] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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162
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Fay KT, Ford ML, Coopersmith CM. The intestinal microenvironment in sepsis. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2574-2583. [PMID: 28286161 PMCID: PMC5589488 DOI: 10.1016/j.bbadis.2017.03.005] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/16/2017] [Accepted: 03/06/2017] [Indexed: 12/17/2022]
Abstract
The gastrointestinal tract has long been hypothesized to function as "the motor" of multiple organ dysfunction syndrome. The gastrointestinal microenvironment is comprised of a single cell layer epithelia, a local immune system, and the microbiome. These three components of the intestine together play a crucial role in maintaining homeostasis during times of health. However, the gastrointestinal microenvironment is perturbed during sepsis, resulting in pathologic changes that drive both local and distant injury. In this review, we seek to characterize the relationship between the epithelium, gastrointestinal lymphocytes, and commensal bacteria during basal and pathologic conditions and how the intestinal microenvironment may be targeted for therapeutic gain in septic patients.
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Affiliation(s)
- Katherine T Fay
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
| | - Mandy L Ford
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States; Emory Transplant Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Craig M Coopersmith
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States; Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA, United States.
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163
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Lorentz CA, Liang Z, Meng M, Chen CW, Yoseph BP, Breed ER, Mittal R, Klingensmith NJ, Farris AB, Burd EM, Koval M, Ford ML, Coopersmith CM. Myosin light chain kinase knockout improves gut barrier function and confers a survival advantage in polymicrobial sepsis. Mol Med 2017; 23:155-165. [PMID: 28598488 DOI: 10.2119/molmed.2016.00256] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 05/31/2017] [Indexed: 02/06/2023] Open
Abstract
Sepsis-induced intestinal hyperpermeability is mediated by disruption of the epithelial tight junction, which is closely associated with the peri-junctional actin-myosin ring. Myosin light chain kinase (MLCK) phosphorylates the myosin regulatory light chain, resulting in increased permeability. The purpose of this study was to determine whether genetic deletion of MLCK would alter gut barrier function and survival from sepsis. MLCK-/- and wild type (WT) mice were subjected to cecal ligation and puncture and assayed for both survival and mechanistic studies. Survival was significantly increased in MLCK-/- mice (95% vs. 24%, p<0.0001). Intestinal permeability increased in septic WT mice compared to unmanipulated mice. In contrast, permeability in septic MLCK-/- mice was similar to that seen in unmanipulated animals. Improved gut barrier function in MLCK-/- mice was associated with increases in the tight junction mediators ZO-1 and claudin 15 without alterations in claudin 1, 2, 3, 4, 5, 7, 8, 13, occludin or JAM-A. Other components of intestinal integrity (apoptosis, proliferation and villus length) were unaffected by MLCK deletion as were local peritoneal inflammation and distant lung injury. Systemic IL-10 was decreased greater than 10-fold in MLCK-/- mice; however, survival was similar between septic MLCK-/- mice given exogenous IL-10 or vehicle. These data demonstrate that deletion of MLCK improves survival following sepsis, associated with normalization of intestinal permeability and selected tight junction proteins.
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Affiliation(s)
- C Adam Lorentz
- Department of Urology, Emory University School of Medicine, Atlanta, GA
| | - Zhe Liang
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Mei Meng
- Department of Critical Care Medicine, Shandong Provincial Hospital Affiliated Shandong University, Jinan, China
| | - Ching-Wen Chen
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Benyam P Yoseph
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Elise R Breed
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Rohit Mittal
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Nathan J Klingensmith
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
| | - Alton B Farris
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA
| | - Eileen M Burd
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA
| | - Michael Koval
- Department of Internal Medicine and Emory Alcohol and Lung Biology Center, Emory University School of Medicine, Atlanta, GA
| | - Mandy L Ford
- Department of Surgery and Emory Transplant Center, Emory University School of Medicine, Atlanta, GA
| | - Craig M Coopersmith
- Department of Surgery and Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA
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164
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Meng M, Klingensmith NJ, Coopersmith CM. New insights into the gut as the driver of critical illness and organ failure. Curr Opin Crit Care 2017; 23:143-148. [PMID: 28092310 PMCID: PMC5373099 DOI: 10.1097/mcc.0000000000000386] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE OF REVIEW The gut has long been hypothesized to be the 'motor' of multiple organ dysfunction syndrome. This review serves as an update on new data elucidating the role of the gut as the propagator of organ failure in critical illness. RECENT FINDINGS Under basal conditions, the gut absorbs nutrients and serves as a barrier that prevents approximately 40 trillion intraluminal microbes and their products from causing host injury. However, in critical illness, gut integrity is disrupted with hyperpermeability and increased epithelial apoptosis, allowing contamination of extraluminal sites that are ordinarily sterile. These alterations in gut integrity are further exacerbated in the setting of preexisting comorbidities. The normally commensal microflora is also altered in critical illness, with increases in microbial virulence and decreases in diversity, which leads to further pathologic responses within the host. SUMMARY All components of the gut are adversely impacted by critical illness. Gut injury can not only propagate local damage, but can also cause distant injury and organ failure. Understanding how the multifaceted components of the gut interact and how these are perturbed in critical illness may play an important role in turning off the 'motor' of multiple organ dysfunction syndrome in the future.
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Affiliation(s)
- Mei Meng
- aDepartment of Critical Care Medicine, Shandong Provincial Hospital Affiliated, Shandong University, Jinan, China bDepartment of Surgery and Emory Center for Critical Care, Emory University School of Medicine, Atlanta, Georgia, USA
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165
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Glucose-Insulin-Potassium Alleviates Intestinal Mucosal Barrier Injuries Involving Decreased Expression of Uncoupling Protein 2 and NLR Family-Pyrin Domain-Containing 3 Inflammasome in Polymicrobial Sepsis. BIOMED RESEARCH INTERNATIONAL 2017; 2017:4702067. [PMID: 28428961 PMCID: PMC5385915 DOI: 10.1155/2017/4702067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/05/2017] [Indexed: 12/18/2022]
Abstract
Uncoupling protein 2 (UCP2) may be critical for intestinal barrier function which may play a key role in the development of sepsis, and insulin has been reported to have anti-inflammatory effects. Male Sprague-Dawley rats were randomly allocated into five groups: control group, cecal ligation and puncture (CLP) group, sham surgery group, CLP plus glucose-insulin-potassium (GIK) group, and CLP plus glucose and potassium (GK) group. Ileum tissues were collected at 24 h after surgery. Histological and cytokine analyses, intestinal permeability tests, and western blots of intestinal epithelial tight junction component proteins and UCP2 were performed. Compared with CLP group, the CLP + GIK group had milder histological damage, lower levels of cytokines in the serum and ileum tissue samples, and lower UCP2 expression, whereas the CLP + GK group had no such effects. Moreover, the CLP + GIK group exhibited decreased epithelial permeability of the ileum and increased expression of zonula occludens-1, occludin, and claudin-1 in the ileum. The findings demonstrated that the UCP2 and NLR family-pyrin domain-containing 3/caspase 1/interleukin 1β signaling pathway may be involved in intestinal barrier injury and that GIK treatment decreased intestinal barrier permeability. Thus, GIK may be a useful treatment for intestinal barrier injury during sepsis.
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166
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Zhao C, Xie T, Li J, Cheng M, Shi J, Gao T, Xi F, Shen J, Cao C, Yu W. Acute Colonic Pseudo-Obstruction with Feeding Intolerance in Critically Ill Patients: A Study according to Gut Wall Analysis. Gastroenterol Res Pract 2017; 2017:9574592. [PMID: 28386273 PMCID: PMC5366232 DOI: 10.1155/2017/9574592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/16/2016] [Accepted: 01/26/2017] [Indexed: 12/13/2022] Open
Abstract
Objective. To compare the differences between acute colonic pseudo-obstruction (ACPO) with and without acute gut wall thickening. Methods. ACPO patients with feeding tolerance were divided into ACPO with no obvious gut wall thickening (ACPO-NT) group and ACPO with obvious acute gut wall thickening (ACPO-T) group according to computed tomography and abdominal radiographs. Patients' condition, responses to supportive measures, pharmacologic therapy, endoscopic decompression, and surgeries and outcomes were compared. Results. Patients in ACPO-T group had a significantly higher APACHE II (11.82 versus 8.25, p = 0.008) and SOFA scores (6.47 versus 3.54, p < 0.001) and a significantly higher 28-day mortality (17.78% versus 4.16%, p = 0.032) and longer intensive care unit stage (4 versus 16 d, p < 0.001). Patients in ACPO-NT group were more likely to be responsive to supportive treatment (62.50% versus 24.44%, p < 0.001), neostigmine (77.78% versus 17.64%, p < 0.001), and colonoscopic decompression (75% versus 42.86%, p = 0.318) than those in ACPO-T group. Of the patients who underwent ileostomy, 81.25% gained benefits. Conclusions. ACPO patients with gut wall thickening are more severe and are less likely to be responsive to nonsurgical treatment. Ileostomy may be a good option for ACPO patients with gut wall thickening who are irresponsive to nonsurgical treatment.
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Affiliation(s)
- Chenyan Zhao
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
- Medical School, Nanjing University, No. 22 Hankou Road, Nanjing 210002, China
| | - Tingbin Xie
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
- Southern Medical University, No. 1023 Shatai South Road, Guangzhou 510515, China
| | - Jun Li
- Jining No.1 People's Hospital, No. 99 Jianshe West Road, Jining 272000, China
| | - Minhua Cheng
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
- Medical School, Nanjing University, No. 22 Hankou Road, Nanjing 210002, China
| | - Jialiang Shi
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
| | - Tao Gao
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
| | - Fengchan Xi
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
| | - Juanhong Shen
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
| | - Chun Cao
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
- Medical School, Nanjing University, No. 22 Hankou Road, Nanjing 210002, China
| | - Wenkui Yu
- Research Institute of General Surgery, Jinling Hospital, No. 305 Zhongshan East Road, Nanjing 210002, China
- Medical School, Nanjing University, No. 22 Hankou Road, Nanjing 210002, China
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167
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Jin L, Batra S, Jeyaseelan S. Deletion of Nlrp3 Augments Survival during Polymicrobial Sepsis by Decreasing Autophagy and Enhancing Phagocytosis. THE JOURNAL OF IMMUNOLOGY 2016; 198:1253-1262. [PMID: 28031338 DOI: 10.4049/jimmunol.1601745] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/25/2016] [Indexed: 01/07/2023]
Abstract
NLRP3 inflammasome is a critical player in innate immunity. Neutrophil recruitment to tissues and effective neutrophil function are critical innate immune mechanisms for bacterial clearance. However, the role of NLRP3 in neutrophil-dependent bacterial clearance in polymicrobial sepsis is unclear. In this study, we evaluated the role of NLRP3 in polymicrobial sepsis induced by cecal ligation and puncture (CLP). Our results showed protection from death in NLRP3-deficient (Nlrp3-/-) and NLRP3 inhibitor-treated wild-type (C57BL/6) mice. Nlrp3-/- and NLRP3 inhibitor-treated mice displayed lower bacterial load but no impairment in neutrophil recruitment to peritoneum. However, neutrophil depletion abrogated protection from death in Nlrp3-/- mice in response to CLP. Intriguingly, following CLP, Nlrp3-/- peritoneal cells (primarily neutrophils) demonstrate decreased autophagy, augmented phagocytosis, and enhanced scavenger receptor (macrophage receptor with collagenous structure) and mannose-binding leptin expression. These findings enhance our understanding of the critical role of NLRP3 in modulating autophagy and phagocytosis in neutrophils and suggest that therapies should be targeted to modulate autophagy and phagocytosis in neutrophils to control bacterial burden in tissues during CLP-induced polymicrobial sepsis.
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Affiliation(s)
- Liliang Jin
- Laboratory of Lung Biology, Department of Pathobiological Sciences and Center for Experimental Infectious Disease Research, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803; and
| | - Sanjay Batra
- Laboratory of Lung Biology, Department of Pathobiological Sciences and Center for Experimental Infectious Disease Research, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803; and
| | - Samithamby Jeyaseelan
- Laboratory of Lung Biology, Department of Pathobiological Sciences and Center for Experimental Infectious Disease Research, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803; and .,Division of Pulmonary and Critical Care, Department of Medicine, LSU Health Sciences Center, New Orleans, LA 70112
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168
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Wu Y, Chung CS, Chen Y, Monaghan SF, Patel S, Huang X, Heffernan DS, Ayala A. A Novel Role for Programmed Cell Death Receptor Ligand-1 (PD-L1) in Sepsis-Induced Intestinal Dysfunction. Mol Med 2016; 22:830-840. [PMID: 27782294 DOI: 10.2119/molmed.2016.00150] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/14/2016] [Indexed: 12/24/2022] Open
Abstract
Studies imply that intestinal barrier dysfunction is a key contributor to morbid events associated with sepsis. Recently, co-inhibitory molecule, programmed death-ligand1 (PD-L1) has been shown to be involved in the regulation of intestinal immune tolerance and/or inflammation. Our previous studies showed that PD-L1 gene deficiency reduced sepsis-induced intestinal injury morphologically. However, it isn't known how PD-L1 expression impacts intestinal barrier dysfunction during sepsis. Here we tested the hypothesis that PD-L1 expressed on intestinal epithelial cells (IECs) has a role in sepsis-induced intestinal barrier dysfunction. To address this, C57BL/6 or PD-L1 gene knockout mice were subjected to experimental sepsis and PD-L1 expression, intestinal permeability, tissue cytokine levels were assessed. Subsequently, septic or non-septic patient colonic samples (assigned by pathology report) were immunohistochemically stained for PD-L1 I a blinded fashion. Finally, human Caco2 cells were used for in vitro studies. The results demonstrated that PD-L1 was constitutively expressed and sepsis significantly up-regulates PD-L1 in IECs from C57BL/6 mice. Concurrently, we observed an increased PD-L1 expression in colon tissue samples from septic patients. PD-L1 gene deficiency reduced ileal permeability, tissue levels of IL-6, TNF-α and MCP-1, and prevented ileal tight junction protein loss compared to WT after sepsis. Comparatively, while Caco2 cell monolayers responded to inflammatory cytokine stimulation also with elevated PD-L1 expression, increased monolayer permeability and altering/decreasing monolayer tight junction protein morphology/expression; these changes were reversed by PD-L1 blocking antibody. Together these data indicate that ligation of ICE PD-L1 plays a novel role in mediating the pathophysiology of sepsis-induced intestinal barrier dysfunction.
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Affiliation(s)
- Youping Wu
- Department of Anesthesiology, Changhai Hospital, Second Military Medical University, Shanghai, 200433, PR China
| | - Chun-Shiang Chung
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
| | - Yaping Chen
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
| | - Sean Farrell Monaghan
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
| | - Sima Patel
- Department of Biochemistry and Molecular Biology, Brown University, Providence, RI 02912, USA
| | - Xin Huang
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
| | - Daithi Seamus Heffernan
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
| | - Alfred Ayala
- Department of Surgery, Division of Surgical Research, the Alpert School of Medicine at Brown University/Rhode Island Hospital, Providence, RI 02903, USA
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Sturgeon C, Fasano A. Zonulin, a regulator of epithelial and endothelial barrier functions, and its involvement in chronic inflammatory diseases. Tissue Barriers 2016; 4:e1251384. [PMID: 28123927 DOI: 10.1080/21688370.2016.1251384] [Citation(s) in RCA: 277] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/14/2016] [Accepted: 10/14/2016] [Indexed: 12/15/2022] Open
Abstract
Beside digesting nutrients and absorbing solutes and electrolytes, the intestinal epithelium with its barrier function is in charge of a tightly controlled antigen trafficking from the intestinal lumen to the submucosa. This trafficking dictates the delicate balance between tolerance and immune response causing inflammation. Loss of barrier function secondary to upregulation of zonulin, the only known physiological modulator of intercellular tight junctions, leads to uncontrolled influx of dietary and microbial antigens. Additional insights on zonulin mechanism of action and the recent appreciation of the role that altered intestinal permeability can play in the development and progression of chronic inflammatory disorders has increased interest of both basic scientists and clinicians on the potential role of zonulin in the pathogenesis of these diseases. This review focuses on the recent research implicating zonulin as a master regulator of intestinal permeability linked to the development of several chronic inflammatory disorders.
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Affiliation(s)
- Craig Sturgeon
- Center for Celiac Research and Treatment, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital and Division of Pediatric Gastroenterology and Nutrition, Boston, MA, USA; Graduate Program in Life Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alessio Fasano
- Center for Celiac Research and Treatment, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital and Division of Pediatric Gastroenterology and Nutrition, Boston, MA, USA; European Biomedical Research Institute of Salerno (EBRIS), Salerno, Italy
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170
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What's New In Shock July 2016? Shock 2016; 46:1-2. [DOI: 10.1097/shk.0000000000000637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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