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Winters TA, Marzella L, Molinar-Inglis O, Price PW, Han NC, Cohen JE, Wang SJ, Fotenos AF, Sullivan JM, Esker JI, Lapinskas PJ, DiCarlo AL. Gastrointestinal Acute Radiation Syndrome: Mechanisms, Models, Markers, and Medical Countermeasures. Radiat Res 2024; 201:628-646. [PMID: 38616048 DOI: 10.1667/rade-23-00196.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 03/14/2024] [Indexed: 04/16/2024]
Abstract
There have been a number of reported human exposures to high dose radiation, resulting from accidents at nuclear power plants (e.g., Chernobyl), atomic bombings (Hiroshima and Nagasaki), and mishaps in industrial and medical settings. If absorbed radiation doses are high enough, evolution of acute radiation syndromes (ARS) will likely impact both the bone marrow as well as the gastrointestinal (GI) tract. Damage incurred in the latter can lead to nutrient malabsorption, dehydration, electrolyte imbalance, altered microbiome and metabolites, and impaired barrier function, which can lead to septicemia and death. To prepare for a medical response should such an incident arise, the National Institute of Allergy and Infectious Diseases (NIAID) funds basic and translational research to address radiation-induced GI-ARS, which remains a critical and prioritized unmet need. Areas of interest include identification of targets for damage and mitigation, animal model development, and testing of medical countermeasures (MCMs) to address GI complications resulting from radiation exposure. To appropriately model expected human responses, it is helpful to study analogous disease states in the clinic that resemble GI-ARS, to inform on best practices for diagnosis and treatment, and translate them back to inform nonclinical drug efficacy models. For these reasons, the NIAID partnered with two other U.S. government agencies (the Biomedical Advanced Research and Development Authority, and the Food and Drug Administration), to explore models, biomarkers, and diagnostics to improve understanding of the complexities of GI-ARS and investigate promising treatment approaches. A two-day workshop was convened in August 2022 that comprised presentations from academia, industry, healthcare, and government, and highlighted talks from 26 subject matter experts across five scientific sessions. This report provides an overview of information that was presented during the conference, and important discussions surrounding a broad range of topics that are critical for the research, development, licensure, and use of MCMs for GI-ARS.
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Affiliation(s)
- Thomas A Winters
- Radiation and Nuclear Countermeasures Program (RNCP), Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, Maryland
| | - Libero Marzella
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, Maryland
| | - Olivia Molinar-Inglis
- Radiation and Nuclear Countermeasures Program (RNCP), Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, Maryland
| | - Paul W Price
- Office of Regulatory Affairs, DAIT, NIAID, NIH, Rockville, Maryland
| | - Nyun Calvin Han
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, Maryland
| | - Jonathan E Cohen
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, Maryland
| | - Sue-Jane Wang
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, Maryland
| | - Anthony F Fotenos
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration (FDA), Silver Spring, Maryland
| | - Julie M Sullivan
- Center for Devices for Radiological Health (CDRH), FDA, Silver Spring, Maryland
| | - John I Esker
- Biomedical Advanced Research and Development Authority (BARDA), Office of the Assistant Secretary for Preparedness and Response (ASPR), Department of Health and Human Services (HHS), Washington, DC
| | - Paula J Lapinskas
- Biomedical Advanced Research and Development Authority (BARDA), Office of the Assistant Secretary for Preparedness and Response (ASPR), Department of Health and Human Services (HHS), Washington, DC
| | - Andrea L DiCarlo
- Radiation and Nuclear Countermeasures Program (RNCP), Division of Allergy, Immunology and Transplantation (DAIT), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rockville, Maryland
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Hutka B, Várallyay A, László SB, Tóth AS, Scheich B, Paku S, Vörös I, Pós Z, Varga ZV, Norman DD, Balogh A, Benyó Z, Tigyi G, Gyires K, Zádori ZS. A dual role of lysophosphatidic acid type 2 receptor (LPAR2) in nonsteroidal anti-inflammatory drug-induced mouse enteropathy. Acta Pharmacol Sin 2024; 45:339-353. [PMID: 37816857 PMCID: PMC10789874 DOI: 10.1038/s41401-023-01175-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 09/21/2023] [Indexed: 10/12/2023] Open
Abstract
Lysophosphatidic acid (LPA) is a bioactive phospholipid mediator that has been found to ameliorate nonsteroidal anti-inflammatory drug (NSAID)-induced gastric injury by acting on lysophosphatidic acid type 2 receptor (LPAR2). In this study, we investigated whether LPAR2 signaling was implicated in the development of NSAID-induced small intestinal injury (enteropathy), another major complication of NSAID use. Wild-type (WT) and Lpar2 deficient (Lpar2-/-) mice were treated with a single, large dose (20 or 30 mg/kg, i.g.) of indomethacin (IND). The mice were euthanized at 6 or 24 h after IND treatment. We showed that IND-induced mucosal enteropathy and neutrophil recruitment occurred much earlier (at 6 h after IND treatment) in Lpar2-/- mice compared to WT mice, but the tissue levels of inflammatory mediators (IL-1β, TNF-α, inducible COX-2, CAMP) remained at much lower levels. Administration of a selective LPAR2 agonist DBIBB (1, 10 mg/kg, i.g., twice at 24 h and 30 min before IND treatment) dose-dependently reduced mucosal injury and neutrophil activation in enteropathy, but it also enhanced IND-induced elevation of several proinflammatory chemokines and cytokines. By assessing caspase-3 activation, we found significantly increased intestinal apoptosis in IND-treated Lpar2-/- mice, but it was attenuated after DBIBB administration, especially in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Finally, we showed that IND treatment reduced the plasma activity and expression of autotaxin (ATX), the main LPA-producing enzyme, and also reduced the intestinal expression of Lpar2 mRNA, which preceded the development of mucosal damage. We conclude that LPAR2 has a dual role in NSAID enteropathy, as it contributes to the maintenance of mucosal integrity after NSAID exposure, but also orchestrates the inflammatory responses associated with ulceration. Our study suggests that IND-induced inhibition of the ATX-LPAR2 axis is an early event in the pathogenesis of enteropathy.
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Affiliation(s)
- Barbara Hutka
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Anett Várallyay
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Szilvia B László
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - András S Tóth
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Bálint Scheich
- Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Sándor Paku
- Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Imre Vörös
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
- HCEMM-SU Cardiometabolic Immunology Research Group, Semmelweis University, Budapest, Hungary
- MTA-SE Momentum Cardio-Oncology and Cardioimmunology Research Group, Budapest, Hungary
- MTA-SE System Pharmacology Research Group, Budapest, Hungary
| | - Zoltán Pós
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Zoltán V Varga
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
- HCEMM-SU Cardiometabolic Immunology Research Group, Semmelweis University, Budapest, Hungary
- MTA-SE Momentum Cardio-Oncology and Cardioimmunology Research Group, Budapest, Hungary
| | - Derek D Norman
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
| | - Andrea Balogh
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Zoltán Benyó
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
- HUN-REN-SU Cerebrovascular and Neurocognitive Diseases Research Group, Budapest, Hungary
| | - Gábor Tigyi
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center (UTHSC), Memphis, TN, USA
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Klára Gyires
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary
| | - Zoltán S Zádori
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary.
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Kenchegowda D, Bolduc DL, Kurada L, Blakely WF. Severity scoring systems for radiation-induced GI injury - Prioritization for use of GI-ARS medical countermeasures. Int J Radiat Biol 2023:1-9. [PMID: 37172305 DOI: 10.1080/09553002.2023.2210669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
PURPOSE Severity scoring systems for ionizing radiation-induced gastrointestinal injury have been used in animal radiation models, human studies involving the use of radiation therapy, and radiation accidents. Various radiation exposure scenarios (i.e., total body irradiation, total abdominal irradiation, etc.) have been used to investigate ionizing radiation-induced gastrointestinal injury. These radiation-induced GI severity scoring systems are based on clinical signs and symptoms and gastrointestinal-specific biomarkers (i.e., citrulline, etc.). In addition, the time course for radiation-induced changes in blood citrulline levels were compared across various animal (i.e., mice, minipigs, Rhesus Macaque, etc.) and human model systems. CONCLUSIONS A worksheet tool was developed to prioritize individuals with severe life-threatening gastrointestinal acute radiation syndrome, based on the design of the Exposure and Symptom Tool addressing hematopoietic acute radiation syndrome, to rescue individuals from potential gastrointestinal acute radiation syndrome injury. This tool provides a triage diagnostic approach to assist first-responders to assess individuals suspected of showing gastrointestinal acute radiation syndrome severity to guide medical management, hence enhancing medical readiness for managing radiological casualties.
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Affiliation(s)
- Doreswamy Kenchegowda
- Biodosimetry Program, Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - David L Bolduc
- Biodosimetry Program, Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Lalitha Kurada
- Biodosimetry Program, Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
- Henry M Jackson Foundation, 6720A Rockledge Drive, Bethesda, MD USA
| | - William F Blakely
- Biodosimetry Program, Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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Nikolovska K, Seidler UE, Stock C. The Role of Plasma Membrane Sodium/Hydrogen Exchangers in Gastrointestinal Functions: Proliferation and Differentiation, Fluid/Electrolyte Transport and Barrier Integrity. Front Physiol 2022; 13:899286. [PMID: 35665228 PMCID: PMC9159811 DOI: 10.3389/fphys.2022.899286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/19/2022] [Indexed: 12/11/2022] Open
Abstract
The five plasma membrane Na+/H+ exchanger (NHE) isoforms in the gastrointestinal tract are characterized by distinct cellular localization, tissue distribution, inhibitor sensitivities, and physiological regulation. NHE1 (Slc9a1) is ubiquitously expressed along the gastrointestinal tract in the basolateral membrane of enterocytes, but so far, an exclusive role for NHE1 in enterocyte physiology has remained elusive. NHE2 (Slc9a2) and NHE8 (Slc9a8) are apically expressed isoforms with ubiquitous distribution along the colonic crypt axis. They are involved in pHi regulation of intestinal epithelial cells. Combined use of a knockout mouse model, intestinal organoid technology, and specific inhibitors revealed previously unrecognized actions of NHE2 and NHE8 in enterocyte proliferation and differentiation. NHE3 (Slc9a3), expressed in the apical membrane of differentiated intestinal epithelial cells, functions as the predominant nutrient-independent Na+ absorptive mechanism in the gut. The new selective NHE3 inhibitor (Tenapanor) allowed discovery of novel pathophysiological and drug-targetable NHE3 functions in cystic-fibrosis associated intestinal obstructions. NHE4, expressed in the basolateral membrane of parietal cells, is essential for parietal cell integrity and acid secretory function, through its role in cell volume regulation. This review focuses on the expression, regulation and activity of the five plasma membrane Na+/H+ exchangers in the gastrointestinal tract, emphasizing their role in maintaining intestinal homeostasis, or their impact on disease pathogenesis. We point to major open questions in identifying NHE interacting partners in central cellular pathways and processes and the necessity of determining their physiological role in a system where their endogenous expression/activity is maintained, such as organoids derived from different parts of the gastrointestinal tract.
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Kaji I, Roland JT, Watanabe M, Engevik AC, Goldstein AE, Hodges CA, Goldenring JR. Lysophosphatidic Acid Increases Maturation of Brush Borders and SGLT1 Activity in MYO5B-deficient Mice, a Model of Microvillus Inclusion Disease. Gastroenterology 2020; 159:1390-1405.e20. [PMID: 32534933 PMCID: PMC8240502 DOI: 10.1053/j.gastro.2020.06.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIM Myosin VB (MYO5B) is an essential trafficking protein for membrane recycling in gastrointestinal epithelial cells. The inactivating mutations of MYO5B cause the congenital diarrheal disease, microvillus inclusion disease (MVID). MYO5B deficiency in mice causes mislocalization of SGLT1 and NHE3, but retained apical function of CFTR, resulting in malabsorption and secretory diarrhea. Activation of lysophosphatidic acid (LPA) receptors can improve diarrhea, but the effect of LPA on MVID symptoms is unclear. We investigated whether LPA administration can reduce the epithelial deficits in MYO5B-knockout mice. METHODS Studies were conducted with tamoxifen-induced, intestine-specific knockout of MYO5B (VilCreERT2;Myo5bflox/flox) and littermate controls. Mice were given LPA, an LPAR2 agonist (GRI977143), or vehicle for 4 days after a single injection of tamoxifen. Apical SGLT1 and CFTR activities were measured in Üssing chambers. Intestinal tissues were collected, and localization of membrane transporters was evaluated by immunofluorescence analysis in tissue sections and enteroids. RNA sequencing and enrichment analysis were performed with isolated jejunal epithelial cells. RESULTS Daily administration of LPA reduced villus blunting, frequency of multivesicular bodies, and levels of cathepsins in intestinal tissues of MYO5B-knockout mice compared with vehicle administration. LPA partially restored the brush border height and the localization of SGLT1 and NHE3 in small intestine of MYO5B-knockout mice and enteroids. The SGLT1-dependent short-circuit current was increased and abnormal CFTR activities were decreased in jejunum from MYO5B-knockout mice given LPA compared with vehicle. CONCLUSIONS LPA may regulate a MYO5B-independent trafficking mechanism and brush border maturation, and therefore be developed for treatment of MVID.
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Affiliation(s)
- Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.
| | - Joseph T. Roland
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | | | - Amy C. Engevik
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Anna E. Goldstein
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Craig A. Hodges
- Cystic Fibrosis Mouse Models Resource Center, Case Western Reserve University, Cleveland, OH
| | - James R. Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan,Cell and Developmental Biology, Vanderbilt University School of Medicine, Sapporo, Japan,Nashville Veterans Affairs Medical Center, Nashville TN
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Sousa FBM, Nolêto IRSG, Chaves LS, Pacheco G, Oliveira AP, Fonseca MMV, Medeiros JVR. A comprehensive review of therapeutic approaches available for the treatment of cholera. J Pharm Pharmacol 2020; 72:1715-1731. [DOI: 10.1111/jphp.13344] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/04/2020] [Indexed: 12/15/2022]
Abstract
Abstract
Objectives
The oral rehydration solution is the most efficient method to treat cholera; however, it does not interfere in the action mechanism of the main virulence factor produced by Vibrio cholerae, the cholera toxin (CT), and this disease still stands out as a problem for human health worldwide. This review aimed to describe therapeutic alternatives available in the literature, especially those related to the search for molecules acting upon the physiopathology of cholera.
Key findings
New molecules have offered a protection effect against diarrhoea induced by CT or even by infection from V. cholerae. The receptor regulator cystic fibrosis channel transmembrane (CFTR), monosialoganglioside (GM1), enkephalinase, AMP-activated protein kinase (AMPK), inhibitors of expression of virulence factors and activators of ADP-ribosylarginine hydrolase are the main therapeutic targets studied. Many of these molecules or extracts still present unclear action mechanisms.
Conclusions
Knowing therapeutic alternatives and their molecular mechanisms for the treatment of cholera could guide us to develop a new drug that could be used in combination with the rehydration solution.
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Affiliation(s)
- Francisca B M Sousa
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
- Northeast Biotechnology Network (RENORBIO), Federal University of Piauí, Teresina, Brazil
| | - Isabela R S G Nolêto
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
- Northeast Biotechnology Network (RENORBIO), Federal University of Piauí, Teresina, Brazil
| | - Leticia S Chaves
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
- Post-graduation Program in Biomedical Sciences, Federal University of Piauí, Parnaíba, Brazil
| | - Gabriella Pacheco
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
| | - Ana P Oliveira
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
- Northeast Biotechnology Network (RENORBIO), Federal University of Piauí, Teresina, Brazil
| | - Mikhail M V Fonseca
- Institute of Higher Education of Vale do Parnaíba (IESVAP), Parnaíba, Brazil
| | - Jand V R Medeiros
- Laboratory of Pharmacology of Inflammation and Gastrointestinal Disorders (Lafidg), Post-graduation Program in Biotechnology, Federal University of Parnaíba Delta, Parnaíba, Brazil
- Northeast Biotechnology Network (RENORBIO), Federal University of Piauí, Teresina, Brazil
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Shukla PK, Meena AS, Gangwar R, Szabo E, Balogh A, Chin Lee S, Vandewalle A, Tigyi G, Rao R. LPAR2 receptor activation attenuates radiation-induced disruption of apical junctional complexes and mucosal barrier dysfunction in mouse colon. FASEB J 2020; 34:11641-11657. [PMID: 32654268 DOI: 10.1096/fj.202000544r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/28/2020] [Accepted: 06/15/2020] [Indexed: 01/13/2023]
Abstract
The tight junction (TJ) and barrier function of colonic epithelium is highly sensitive to ionizing radiation. We evaluated the effect of lysophosphatidic acid (LPA) and its analog, Radioprotein-1, on γ-radiation-induced colonic epithelial barrier dysfunction using Caco-2 and m-ICC12 cell monolayers in vitro and mice in vivo. Mice were subjected to either total body irradiation (TBI) or partial body irradiation (PBI-BM5). Intestinal barrier function was assessed by analyzing immunofluorescence localization of TJ proteins, mucosal inulin permeability, and plasma lipopolysaccharide (LPS) levels. Oxidative stress was analyzed by measuring protein thiol oxidation and antioxidant mRNA. In Caco-2 and m-ICC12 cell monolayers, LPA attenuated radiation-induced redistribution of TJ proteins, which was blocked by a Rho-kinase inhibitor. In mice, TBI and PBI-BM5 disrupted colonic epithelial tight junction and adherens junction, increased mucosal permeability, and elevated plasma LPS; TJ disruption by TBI was more severe in Lpar2-/- mice compared to wild-type mice. RP1, administered before or after irradiation, alleviated TBI and PBI-BM5-induced TJ disruption, barrier dysfunction, and endotoxemia accompanied by protein thiol oxidation and downregulation of antioxidant gene expression, cofilin activation, and remodeling of the actin cytoskeleton. These data demonstrate that LPAR2 receptor activation prevents and mitigates γ-irradiation-induced colonic mucosal barrier dysfunction and endotoxemia.
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Affiliation(s)
- Pradeep K Shukla
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Avtar S Meena
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Ruchika Gangwar
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Erzsebet Szabo
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Andrea Balogh
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Sue Chin Lee
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Alain Vandewalle
- INSERM U773, Centre de Recherche Biomédicale, Bichat-Beaujon, CRB3, UFR de Médecine, Paris Cedex 18, France
| | - Gabor Tigyi
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - RadhaKrishna Rao
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
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Kaunitz JD. Oral Defense: How Oral Rehydration Solutions Revolutionized the Treatment of Toxigenic Diarrhea. Dig Dis Sci 2020; 65:345-348. [PMID: 31900719 PMCID: PMC7193728 DOI: 10.1007/s10620-019-06023-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jonathan D. Kaunitz
- Medical Service, West Los Angeles VAMC and Departments of Medicine and Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
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Tigyi GJ, Johnson LR, Lee SC, Norman DD, Szabo E, Balogh A, Thompson K, Boler A, McCool WS. Lysophosphatidic acid type 2 receptor agonists in targeted drug development offer broad therapeutic potential. J Lipid Res 2019; 60:464-474. [PMID: 30692142 PMCID: PMC6399510 DOI: 10.1194/jlr.s091744] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/15/2019] [Indexed: 11/20/2022] Open
Abstract
The growth factor-like lipid mediator, lysophosphatidic acid (LPA), is a potent signaling molecule that influences numerous physiologic and pathologic processes. Manipulation of LPA signaling is of growing pharmacotherapeutic interest, especially because LPA resembles compounds with drug-like features. The action of LPA is mediated through activation of multiple types of molecular targets, including six G protein-coupled receptors that are clear targets for drug development. However, the LPA signaling has been linked to pathological responses that include promotion of fibrosis, atherogenesis, tumorigenesis, and metastasis. Thus, a question arises: Can we harness, in an LPA-like drug, the many beneficial activities of this lipid without eliciting its dreadful actions? We developed octadecyl thiophosphate (OTP; subsequently licensed as Rx100), an LPA mimic with higher stability in vivo than LPA. This article highlights progress made toward developing analogs like OTP and exploring prosurvival and regenerative LPA signaling. We determined that LPA prevents cell death triggered by various cellular stresses, including genotoxic stressors, and rescues cells condemned to apoptosis. LPA2 agonists provide a new treatment option for secretory diarrhea and reduce gastric erosion caused by nonsteroidal anti-inflammatory drugs. The potential uses of LPA2 agonists like OTP and sulfamoyl benzoic acid-based radioprotectins must be further explored for therapeutic uses.
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Affiliation(s)
- Gabor J Tigyi
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- RxBio Inc. Memphis, TN 38163
- Research Division Veterans Affairs Medical Center, Memphis, TN 38104
| | - Leonard R Johnson
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- RxBio Inc. Memphis, TN 38163
| | - Sue Chin Lee
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
| | - Derek D Norman
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- Research Division Veterans Affairs Medical Center, Memphis, TN 38104
| | - Erzsebet Szabo
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
| | - Andrea Balogh
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
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