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Khair S, Walrath TM, Curtis BJ, Orlicky DJ, McMahan RH, Kovacs EJ. Ethanol exacerbates pulmonary complications after burn injury in mice, regardless of frequency of ethanol exposures. Burns 2023; 49:1935-1943. [PMID: 37574341 PMCID: PMC10811296 DOI: 10.1016/j.burns.2023.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 06/25/2023] [Accepted: 07/13/2023] [Indexed: 08/15/2023]
Abstract
Burn injuries are associated with significant morbidity and mortality, and lungs are the most common organ to fail. Interestingly, patients with alcohol intoxication at the time of burn have worse clinical outcomes, including pulmonary complications. Using a clinically relevant murine model, we have previously reported that episodic ethanol exposure before burn exacerbated lung inflammation. Specifically, intoxicated burned mice had worsened pulmonary responses, including increased leukocyte infiltration and heightened levels of CXCL1 and IL-6. Herein, we examined whether a single binge ethanol exposure before scald burn injury yields similar pulmonary responses. C57BL/6 male mice were given ethanol (1.2 g/kg) 30 min before a 15 % total body surface area burn. These mice were compared to a second cohort given episodic ethanol binge for a total of 6 days (3 days ethanol, 4 days rest, 3 days ethanol) prior to burn injury. 24 h after burn, histopathological examination of lungs were performed. In addition, survival, and levels of infiltrating leukocytes, CXCL1, and IL-6 were quantified. Episodic and single ethanol exposure before burn decreased survival compared to burn only mice and sham vehicle mice, respectively (p < 0.05). However, no difference in survival was observed between burned mice with single and episodic ethanol binge. Examination of H&E-stained lung sections revealed that regardless of ethanol binge frequency, intoxication prior to burn worsened pulmonary inflammation, evidenced by elevated granulocyte accumulation and congestion, relative to burned mice without any ethanol exposure. Levels of infiltrating granulocyte in the lungs were significantly higher in burned mice with both episodic and single ethanol intoxication, compared to burn injury only (p < 0.05). In addition, there was no difference in the granulocyte count between single and ethanol binge mice with burn injury. Neutrophil chemoattractant CXCL1 levels in the lung were similarly increased following single and episodic ethanol exposure prior to burn compared to burn alone (22-fold and 26-fold respectively, p < 0.05). Lastly, we assessed pulmonary IL-6, which revealed that irrespective of frequency, ethanol exposure combined with burn injury raised pro-inflammatory cytokine IL-6 in the lungs relative to burn mice. Again, we did not find any difference in the amount of IL-6 in lungs of burned mice with single and episodic ethanol intoxication. Taken altogether, these data demonstrate that both single and episodic exposure to ethanol prior to burn injury similarly worsens pulmonary inflammation. These results suggest that ethanol-induced exacerbation of the pulmonary responses to burn injury is due to presence of ethanol at the time of injury rather than longer-term effects of ethanol exposure.
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Affiliation(s)
- Shanawaj Khair
- Department of Surgery, Division of GI, Trauma, and Endocrine Surgery, and Alcohol Research Program, Burn Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Molecular Biology Graduate Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Medical Scientist Training Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Travis M Walrath
- Department of Surgery, Division of GI, Trauma, and Endocrine Surgery, and Alcohol Research Program, Burn Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Brenda J Curtis
- Department of Surgery, Division of GI, Trauma, and Endocrine Surgery, and Alcohol Research Program, Burn Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - David J Orlicky
- Department of Pathology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rachel H McMahan
- Department of Surgery, Division of GI, Trauma, and Endocrine Surgery, and Alcohol Research Program, Burn Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Veterans Health Administration, Eastern Colorado Health Care System, Rocky Mountain Regional Veterans Affairs Medical Center (RMRVAMC), Aurora, CO 80045, USA
| | - Elizabeth J Kovacs
- Department of Surgery, Division of GI, Trauma, and Endocrine Surgery, and Alcohol Research Program, Burn Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Molecular Biology Graduate Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Medical Scientist Training Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA; Veterans Health Administration, Eastern Colorado Health Care System, Rocky Mountain Regional Veterans Affairs Medical Center (RMRVAMC), Aurora, CO 80045, USA.
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2
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Wu X, Fan X, McMullen MR, Miyata T, Kim A, Pathak V, Wu J, Day LZ, Hardesty JE, Welch N, Dasarathy J, Allende DS, McCullough AJ, Jacobs JM, Rotroff DM, Dasarathy S, Nagy LE. Macrophage-derived MLKL in alcohol-associated liver disease: Regulation of phagocytosis. Hepatology 2023; 77:902-919. [PMID: 35689613 PMCID: PMC9741663 DOI: 10.1002/hep.32612] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS Mixed lineage kinase domain-like pseudokinase (MLKL), a key terminal effector of necroptosis, also plays a role in intracellular vesicle trafficking that is critical for regulating liver inflammation and injury in alcohol-associated liver disease (ALD). Although receptor interacting protein kinase 3 (Rip3)-/- mice are completely protected from ethanol-induced liver injury, Mlkl-/- mice are only partially protected. Therefore, we hypothesized that cell-specific functions of MLKL may contribute to ethanol-induced injury. APPROACH AND RESULTS Bone marrow transplants between Mlkl-/- mice and littermates were conducted to distinguish the role of myeloid versus nonmyeloid Mlkl in the Gao-binge model of ALD. Ethanol-induced hepatic injury, steatosis, and inflammation were exacerbated in Mlkl-/- →wild-type (WT) mice, whereas Mlkl deficiency in nonmyeloid cells (WT→ Mlkl-/- ) had no effect on Gao-binge ethanol-induced injury. Importantly, Mlkl deficiency in myeloid cells exacerbated ethanol-mediated bacterial burden and accumulation of immune cells in livers. Mechanistically, challenging macrophages with lipopolysaccharide (LPS) induced signal transducer and activator of transcription 1-mediated expression and phosphorylation of MLKL, as well as translocation and oligomerization of MLKL to intracellular compartments, including phagosomes and lysosomes but not plasma membrane. Importantly, pharmacological or genetic inhibition of MLKL suppressed the phagocytic capability of primary mouse Kupffer cells (KCs) at baseline and in response to LPS with/without ethanol as well as peripheral monocytes isolated from both healthy controls and patients with alcohol-associated hepatitis. Further, in vivo studies revealed that KCs of Mlkl-/- mice phagocytosed fewer bioparticles than KCs of WT mice. CONCLUSION Together, these data indicate that myeloid MLKL restricts ethanol-induced liver inflammation and injury by regulating hepatic immune cell homeostasis and macrophage phagocytosis.
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Affiliation(s)
- Xiaoqin Wu
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Xiude Fan
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Megan R. McMullen
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Tatsunori Miyata
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Adam Kim
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Vai Pathak
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jianguo Wu
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Le Z. Day
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Josiah E. Hardesty
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Nicole Welch
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jaividhya Dasarathy
- Department of Family Medicine, Metro Health Medical Center, Case Western Reserve University, Cleveland, Ohio, USA
| | | | - Arthur J. McCullough
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jon M. Jacobs
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Daniel M. Rotroff
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio, USA
- Endocrine and Metabolism Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Srinivasan Dasarathy
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Laura E. Nagy
- Northern Ohio Alcohol Center, Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, Ohio, USA
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Gandhirajan A, Roychowdhury S, Kibler C, Cross E, Abraham S, Bellar A, Nagy LE, Scheraga RG, Vachharajani V. SIRT2-PFKP interaction dysregulates phagocytosis in macrophages with acute ethanol-exposure. Front Immunol 2023; 13:1079962. [PMID: 36865524 PMCID: PMC9972587 DOI: 10.3389/fimmu.2022.1079962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 12/27/2022] [Indexed: 01/28/2023] Open
Abstract
Alcohol abuse, reported by 1/8th critically ill patients, is an independent risk factor for death in sepsis. Sepsis kills over 270,000 patients/year in the US. We reported that the ethanol-exposure suppresses innate-immune response, pathogen clearance, and decreases survival in sepsis-mice via sirtuin 2 (SIRT2). SIRT2 is an NAD+-dependent histone-deacetylase with anti-inflammatory properties. We hypothesized that in ethanol-exposed macrophages, SIRT2 suppresses phagocytosis and pathogen clearance by regulating glycolysis. Immune cells use glycolysis to fuel increased metabolic and energy demand of phagocytosis. Using ethanol-exposed mouse bone marrow- and human blood monocyte-derived macrophages, we found that SIRT2 mutes glycolysis via deacetylating key glycolysis regulating enzyme phosphofructokinase-platelet isoform (PFKP), at mouse lysine 394 (mK394, human: hK395). Acetylation of PFKP at mK394 (hK395) is crucial for PFKP function as a glycolysis regulating enzyme. The PFKP also facilitates phosphorylation and activation of autophagy related protein 4B (Atg4B). Atg4B activates microtubule associated protein 1 light chain-3B (LC3). LC3 is a driver of a subset of phagocytosis, the LC3-associated phagocytosis (LAP), which is crucial for segregation and enhanced clearance of pathogens, in sepsis. We found that in ethanol-exposed cells, the SIRT2-PFKP interaction leads to decreased Atg4B-phosphorylation, decreased LC3 activation, repressed phagocytosis and LAP. Genetic deficiency or pharmacological inhibition of SIRT2 reverse PFKP-deacetylation, suppressed LC3-activation and phagocytosis including LAP, in ethanol-exposed macrophages to improve bacterial clearance and survival in ethanol with sepsis mice.
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Affiliation(s)
- Anugraha Gandhirajan
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Sanjoy Roychowdhury
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Christopher Kibler
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Emily Cross
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Susamma Abraham
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Annett Bellar
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Laura E. Nagy
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
| | - Rachel Greenberg Scheraga
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
- Department of Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Vidula Vachharajani
- Department of Inflammation and Immunity, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States
- Department of Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States
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Barbaro JM, Jaureguiberry-Bravo M, Sidoli S, Berman JW. Morphine disrupts macrophage functions even during HIV infection. J Leukoc Biol 2022; 112:1317-1328. [PMID: 36205434 PMCID: PMC9677813 DOI: 10.1002/jlb.3ma0522-273rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/1912] [Revised: 12/12/1912] [Accepted: 12/12/1912] [Indexed: 12/24/2022] Open
Abstract
HIV-associated neurocognitive impairment (HIV-NCI) is a debilitating comorbidity that reduces quality of life in 15-40% of people with HIV (PWH) taking antiretroviral therapy (ART). Opioid use has been shown to increase neurocognitive deficits in PWH. Monocyte-derived macrophages (MDMs) harbor HIV in the CNS even in PWH on ART. We hypothesized that morphine (MOR), a metabolite of heroin, further dysregulates functional processes in MDMs to increase neuropathogenesis. We found that, in uninfected and HIV-infected primary human MDMs, MOR activates these cells by increasing phagocytosis and up-regulating reactive oxygen species. Effects of MOR on phagocytosis were dependent on μ-opioid receptor activity and were mediated, in part, by inhibited lysosomal degradation of phagocytized substrates. All results persisted when cells were treated with both MOR and a commonly prescribed ART cocktail, suggesting minimal impact of ART during opioid exposure. We then performed mass spectrometry in HIV-infected MDMs treated with or without MOR to determine proteomic changes that suggest additional mechanisms by which opioids affect macrophage homeostasis. Using downstream pathway analyses, we found that MOR dysregulates ER quality control and extracellular matrix invasion. Our data indicate that MOR enhances inflammatory functions and impacts additional cellular processes in HIV-infected MDMs to potentially increases neuropathogenesis in PWH using opioids.
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Affiliation(s)
- John M. Barbaro
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | - Matias Jaureguiberry-Bravo
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | - Simone Sidoli
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | - Joan W. Berman
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
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5
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Lewis SA, Doratt BM, Sureshchandra S, Jankeel A, Newman N, Shen W, Grant KA, Messaoudi I. Ethanol Consumption Induces Nonspecific Inflammation and Functional Defects in Alveolar Macrophages. Am J Respir Cell Mol Biol 2022; 67:112-124. [PMID: 35380939 PMCID: PMC9273227 DOI: 10.1165/rcmb.2021-0346oc] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 04/05/2022] [Indexed: 11/24/2022] Open
Abstract
Chronic alcohol drinking is associated with increased susceptibility to viral and bacterial respiratory pathogens. In this study, we use a rhesus macaque model of voluntary ethanol self-administration to study the effects of long-term alcohol drinking on the immunological landscape of the lung. We report a heightened inflammatory state in alveolar macrophages (AMs) obtained from ethanol (EtOH)-drinking animals that is accompanied by increased chromatin accessibility in intergenic regions that regulate inflammatory genes and contain binding motifs for transcription factors AP-1, IRF8, and NFKB p-65. In line with these transcriptional and epigenetic changes at the basal state, AMs from EtOH-drinking animals generate elevated inflammatory mediator responses to lipopolysaccharides and respiratory syncytial virus. However, the transcriptional analysis revealed an inefficient induction of interferon-stimulated genes with EtOH in response to the respiratory syncytial virus, suggesting disruption of antimicrobial defenses. Correspondingly, AMs from EtOH-drinking animals exhibited transcriptional shifts indicative of increased oxidative stress and oxidative phosphorylation, which was coupled with higher cytosolic reactive oxygen species and mitochondrial potential. This heightened oxidative stress state was accompanied by decreased ability to phagocytose bacteria. Bulk RNA and assay for transposase-accessible chromatin sequencing data further revealed reduced expression and chromatin accessibility of loci associated with tissue repair and maintenance with chronic EtOH drinking. Similarly, analysis of single-cell RNA sequencing data revealed shifts in cell states from tissue maintenance to inflammatory responses with EtOH. Collectively, these data provide novel insight into mechanisms by which chronic EtOH drinking increases susceptibility to infection in patients with alcohol use disorders.
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Affiliation(s)
- Sloan A. Lewis
- Department of Molecular Biology and Biochemistry
- Institute for Immunology, and
| | - Brianna M. Doratt
- Department of Molecular Biology and Biochemistry
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, Kentucky; and
| | - Suhas Sureshchandra
- Department of Molecular Biology and Biochemistry
- Institute for Immunology, and
| | | | - Natali Newman
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon
| | - Weining Shen
- Department of Statistics, University of California, Irvine, Irvine, California
| | - Kathleen A. Grant
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon
| | - Ilhem Messaoudi
- Department of Molecular Biology and Biochemistry
- Institute for Immunology, and
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, Kentucky; and
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6
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Hulsebus HJ, Najarro KM, McMahan RH, Boe DM, Orlicky DJ, Kovacs EJ. Ethanol Intoxication Impairs Respiratory Function and Bacterial Clearance and Is Associated With Neutrophil Accumulation in the Lung After Streptococcus pneumoniae Infection. Front Immunol 2022; 13:884719. [PMID: 35603143 PMCID: PMC9116899 DOI: 10.3389/fimmu.2022.884719] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 04/11/2022] [Indexed: 11/27/2022] Open
Abstract
Alcohol consumption is commonplace in the United States and its prevalence has increased in recent years. Excessive alcohol use is linked to an increased risk of infections including pneumococcal pneumonia, mostly commonly caused by Streptococcus pneumoniae. In addition, pneumonia patients with prior alcohol use often require more intensive treatment and longer hospital stays due to complications of infection. The initial respiratory tract immune response to S. pneumoniae includes the production of pro-inflammatory cytokines and chemokines by resident cells in the upper and lower airways which activate and recruit leukocytes to the site of infection. However, this inflammation must be tightly regulated to avoid accumulation of toxic by-products and subsequent tissue damage. A majority of previous work on alcohol and pneumonia involve animal models utilizing high concentrations of ethanol or chronic exposure and offer conflicting results about how ethanol alters immunity to pathogens. Further, animal models often employ a high bacterial inoculum which may overwhelm the immune system and obscure results, limiting their applicability to the course of human infection. Here, we sought to determine how a more moderate ethanol exposure paradigm affects respiratory function and innate immunity in mice after intranasal infection with 104 colony forming units of S. pneumoniae. Ethanol-exposed mice displayed respiratory dysfunction and impaired bacterial clearance after infection compared to their vehicle-exposed counterparts. This altered response was associated with increased gene expression of neutrophil chemokines Cxcl1 and Cxcl2 in whole lung homogenates, elevated concentrations of circulating granulocyte-colony stimulating factor (G-CSF), and higher neutrophil numbers in the lung 24 hours after infection. Taken together, these findings suggest that even a more moderate ethanol consumption pattern can dramatically modulate the innate immune response to S. pneumoniae after only 3 days of ethanol exposure and provide insight into possible mechanisms related to the compromised respiratory immunity seen in alcohol consumers with pneumonia.
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Affiliation(s)
- Holly J Hulsebus
- Department of Surgery, Division of GI, Trauma and Endocrine Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Immunology Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Kevin M Najarro
- Department of Surgery, Division of GI, Trauma and Endocrine Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Rachel H McMahan
- Department of Surgery, Division of GI, Trauma and Endocrine Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Devin M Boe
- Department of Surgery, Division of GI, Trauma and Endocrine Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Immunology Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - David J Orlicky
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Elizabeth J Kovacs
- Department of Surgery, Division of GI, Trauma and Endocrine Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Immunology Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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7
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Effects of Multiday Ethanol Intoxication on Postburn Inflammation, Lung Function, and Alveolar Macrophage Phenotype. Shock 2020; 51:625-633. [PMID: 29846360 DOI: 10.1097/shk.0000000000001188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Burn patients who consumed alcohol before injury have worse clinical outcomes, including longer hospital stays, increased ventilator days, and more respiratory infections. Most alcohol consumers are binge drinkers and not chronic alcoholics, and binge drinking patterns fluctuate over the week, with consecutive days of drinking over the weekend followed by relative abstinence during the week. We used a murine model simulating this drinking pattern in the context of burn injury. Mice were given ethanol for 3 days, rested for 4 days, given ethanol for 3 more days, followed by a sham or 15% total body surface area full-thickness burn. We previously demonstrated that mice exposed to the combined insult exhibited respiratory dysfunction and 50% mortality, with those that succumbed to injury dying between 24 and 72 h, thus identifying a therapeutic intervention window. Our goal herein is to characterize inflammatory and respiratory parameters during this critical time frame. We saw that mice exposed to the combined insult had the highest circulating and pulmonary cytokine levels at 24 h, which were normalized by 72 h in survivors. Alveolar macrophage activation was observed at 24 h in burned mice, regardless of intoxication (P < 0.05). However, at 72 h, alveolar macrophages from intoxicated burned mice had elevated CD206, relative to controls (P < 0.05), indicative of an anti-inflammatory phenotype. Taken together, these findings suggest that although lung function and inflammation are normalized by 72 h, the alterations in alveolar macrophage phenotype shed light on a potential mechanism underlying increased infection susceptibility in intoxicated burn patients.
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8
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Gough ME, Graviss EA, Chen TA, Obasi EM, May EE. Compounding effect of vitamin D 3 diet, supplementation, and alcohol exposure on macrophage response to mycobacterium infection. Tuberculosis (Edinb) 2019; 116S:S42-S58. [PMID: 31126718 DOI: 10.1016/j.tube.2019.04.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 12/14/2022]
Abstract
Vitamin D3 is known to be a key component in the defense against Mycobacterium tuberculosis (Mtb) infection through the regulation of cytokine and effector molecules. Conversely, alcohol exposure has been recognized as an immune dysregulator. Macrophages were extracted from D3 deficient and sufficient diet mice and supplemented with D3 or exposed to ethanol during ex vivo infection using M. bovis BCG, as a surrogate for Mtb. Results of our study indicate that while exogenous supplementation or alcohol exposure did alter immune response, in vivo diet was the greatest determinant of cytokine and effector molecule production. Alcohol exposure was found to profoundly dysregulate primary murine macrophages, with ethanol-exposed cells generally characterized as hyper- or hyporesponsive. Exogenous D3 supplementation had a normative effect for diet deficient host, however supplementation was not sufficient to compensate for the effects of diet deficiency. Vitamin D3 sufficient diet resulted in reduced cell cytotoxicity for the majority of time points. Results provide insight into the ramifications of both the individual and combined health risks of D3 deficiency or alcohol exposure. Given the clinical relevance of D3 deficiency and alcohol use comorbidities, outcomes of this study have implications in therapeutic approaches for the treatment of tuberculosis disease.
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Affiliation(s)
- Maya E Gough
- Biomedical Engineering Department, University of Houston, USA
| | - Edward A Graviss
- Pathology & Genomic Medicine, Houston Methodist Research Institute, USA
| | - Tzu-An Chen
- HEALTH Research Institute, University of Houston, USA
| | - Ezemenari M Obasi
- HEALTH Research Institute, University of Houston, USA; Psychological, Health, & Learning Sciences Department, University of Houston, USA
| | - Elebeoba E May
- Biomedical Engineering Department, University of Houston, USA; HEALTH Research Institute, University of Houston, USA.
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9
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Methamphetamine Impairs IgG1-Mediated Phagocytosis and Killing of Cryptococcus neoformans by J774.16 Macrophage- and NR-9640 Microglia-Like Cells. Infect Immun 2019; 87:IAI.00113-18. [PMID: 30510106 DOI: 10.1128/iai.00113-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 11/27/2018] [Indexed: 01/14/2023] Open
Abstract
The prevalence of methamphetamine (METH) use is estimated at ∼35 million people worldwide, with over 10 million users in the United States. Chronic METH abuse and dependence predispose the users to participate in risky behaviors that may result in the acquisition of HIV and AIDS-related infections. Cryptococcus neoformans is an encapsulated fungus that causes cryptococcosis, an opportunistic infection that has recently been associated with drug users. METH enhances C. neoformans pulmonary infection, facilitating its dissemination and penetration into the central nervous system in mice. C. neoformans is a facultative intracellular microorganism and an excellent model to study host-pathogen interactions. METH compromises phagocyte effector functions, which might have deleterious consequences on infection control. In this study, we investigated the role of METH in phagocytosis and antigen processing by J774.16 macrophage- and NR-9460 microglia-like cells in the presence of a specific IgG1 to C. neoformans capsular polysaccharide. METH inhibits antibody-mediated phagocytosis of cryptococci by macrophages and microglia, likely due to reduced expression of membrane-bound Fcγ receptors. METH interferes with phagocytic cells' phagosomal maturation, resulting in impaired fungal control. Phagocytic cell reduction in nitric oxide production during interactions with cryptococci was associated with decreased levels of tumor necrosis factor alpha (TNF-α) and lowered expression of Fcγ receptors. Importantly, pharmacological levels of METH in human blood and organs are cytotoxic to ∼20% of the phagocytes. Our findings suggest that METH abrogates immune cellular and molecular functions and may be deadly to phagocytic cells, which may result in increased susceptibility of users to acquire infectious diseases.
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10
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Wang S, Cao Y, Deng S, Jiang X, Wang J, Zhang X, Zhang J, Liu G, Lian Z. Overexpression of Toll-like Receptor 4-linked Mitogen-activated Protein Kinase Signaling Contributes to Internalization of Escherichia coli in Sheep. Int J Biol Sci 2018; 14:1022-1032. [PMID: 29989103 PMCID: PMC6036738 DOI: 10.7150/ijbs.25275] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/28/2018] [Indexed: 12/17/2022] Open
Abstract
Escherichia coli is one of the most common causal pathogens of mastitis in milk-producing mammals. Toll-like receptor 4 (TLR4) is important for host recognition of this bacteria. Increased activation of TLR4 can markedly enhance the internalization of E. coli. In this study, the relationship between TLR4 and mitogen-activated protein kinase (MAPK) signaling pathways in mediating E. coli internalization was evaluated in sheep monocytes. Using a TLR4-overexpressing transgenic (Tg) sheep model, we explored the bacterial internalization mechanism in sheep. We found that monocytes of Tg sheep could phagocytize more bacteria and exhibited higher adhesive capacity. The specific inhibition of p38 MAPK or c-Jun N-terminal kinase (JNK) or extracellular signal-regulated kinases (ERKs) reduced TLR4-dependent internalization of bacteria into sheep monocytes. Furthermore, the inhibition of MAPK signaling down-regulated the adhesive capacity of monocytes and the expression of scavenger receptors and adhesion molecules. Taken together, the overexpression of TLR4 in transgenic sheep enhanced the internalization of E. coli via MAPK signaling.
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Affiliation(s)
- Sutian Wang
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yang Cao
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Shoulong Deng
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China.,State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xiaojing Jiang
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jiahao Wang
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | | | - Jinlong Zhang
- Tianjin Institute of Animal Sciences, Tianjin, China
| | - Guoshi Liu
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Zhengxing Lian
- Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China
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11
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Kalinin S, González-Prieto M, Scheiblich H, Lisi L, Kusumo H, Heneka MT, Madrigal JLM, Pandey SC, Feinstein DL. Transcriptome analysis of alcohol-treated microglia reveals downregulation of beta amyloid phagocytosis. J Neuroinflammation 2018; 15:141. [PMID: 29759078 PMCID: PMC5952855 DOI: 10.1186/s12974-018-1184-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 04/29/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Microglial activation contributes to the neuropathology associated with chronic alcohol exposure and withdrawal, including the expression of inflammatory and anti-inflammatory genes. In the current study, we examined the transcriptome of primary rat microglial cells following incubation with alcohol alone, or alcohol together with a robust inflammatory stimulus. METHODS Primary microglia were prepared from mixed rat glial cultures. Cells were incubated with 75 mM ethanol alone or with proinflammatory cytokines ("TII": IL1β, IFNγ, and TNFα). Isolated mRNA was used for RNAseq analysis and qPCR. Effects of alcohol on phagocytosis were determined by uptake of oligomeric amyloid beta. RESULTS Alcohol induced nitrite production in control cells and increased nitrite production in cells co-treated with TII. RNAseq analysis of microglia exposed for 24 h to alcohol identified 312 differentially expressed mRNAs ("Alc-DEs"), with changes confirmed by qPCR analysis. Gene ontology analysis identified phagosome as one of the highest-ranking KEGG pathways including transcripts regulating phagocytosis. Alcohol also increased several complement-related mRNAs that have roles in phagocytosis, including C1qa, b, and c; C3; and C3aR1. RNAseq analysis identified over 3000 differentially expressed mRNAs in microglia following overnight incubation with TII; and comparison to the group of Alc-DEs revealed 87 mRNAs modulated by alcohol but not by TII, including C1qa, b, and c. Consistent with observed changes in phagocytosis-related mRNAs, the uptake of amyloid beta1-42, by primary microglia, was reduced by alcohol. CONCLUSIONS Our results define alterations that occur to microglial gene expression following alcohol exposure and suggest that alcohol effects on phagocytosis could contribute to the development of Alzheimer's disease.
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Affiliation(s)
- Sergey Kalinin
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Marta González-Prieto
- Department of Pharmacology, University Complutense, Centro de Investigacion Biomedica en Red de Salud Mental (CIBERSAM), Madrid, 28040 Spain
| | - Hannah Scheiblich
- Department of Neurodegenerative Disease and Geriatric Psychiatry, University of Bonn, 53127 Bonn, Germany
| | - Lucia Lisi
- Institute of Pharmacology, Catholic University Medical School, 00168 Rome, Italy
| | - Handojo Kusumo
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Michael T. Heneka
- Department of Neurodegenerative Disease and Geriatric Psychiatry, University of Bonn, 53127 Bonn, Germany
| | - Jose L. M. Madrigal
- Department of Pharmacology, University Complutense, Centro de Investigacion Biomedica en Red de Salud Mental (CIBERSAM), Madrid, 28040 Spain
| | - Subhash C. Pandey
- Center for Alcohol Research in Epigenetics, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612 USA
- Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL 60612 USA
| | - Douglas L. Feinstein
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, IL 60612 USA
- Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL 60612 USA
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12
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Thompson MG, Navarro F, Chitsike L, Ramirez L, Kovacs EJ, Watkins SK. Alcohol exposure differentially effects anti-tumor immunity in females by altering dendritic cell function. Alcohol 2016; 57:1-8. [PMID: 27916138 DOI: 10.1016/j.alcohol.2016.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 12/18/2022]
Abstract
Dendritic cells (DCs) are a critical component of anti-tumor immunity due to their ability to induce a robust immune response to antigen (Ag). Alcohol was previously shown to reduce DC ability to present foreign Ag and promote pro-inflammatory responses in situations of infection and trauma. However the impact of alcohol exposure on generation of an anti-tumor response, especially in the context of generation of an immune vaccine has not been examined. In the clinic, DC vaccines are typically generated from autologous blood, therefore prior exposure to substances such as alcohol may be a critical factor to consider regarding the effectiveness in generating an immune response. In this study, we demonstrate for the first time that ethanol differentially affects DC and tumor Ag-specific T cell responses depending on sex. Signaling pathways were found to be differentially regulated in DC in females compared to males and these differences were exacerbated by ethanol treatment. DC from female mice treated with ethanol were unable to activate Ag-specific cytotoxic T cells (CTL) as shown by reduced expression of CD44, CD69, and decreased production of granzyme B and IFNγ. Furthermore, although FOXO3, an immune suppressive mediator of DC function, was found to be upregulated in DC from female mice, ethanol related suppression was independent of FOXO3. These findings demonstrate for the first time differential impacts of alcohol on the immune system of females compared to males and may be a critical consideration for determining the effectiveness of an immune based therapy for cancer in patients that consume alcohol.
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Affiliation(s)
- Matthew G Thompson
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA
| | - Flor Navarro
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA
| | - Lennox Chitsike
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA
| | - Luis Ramirez
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA
| | - Elizabeth J Kovacs
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA; University of Colorado Denver, Department of Surgery, Aurora, CO, USA
| | - Stephanie K Watkins
- Loyola University Chicago, Department of Surgery, Cardinal Bernardin Cancer Center, Maywood, IL 60153, USA.
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13
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Gofman L, Fernandes NC, Potula R. Relative Role of Akt, ERK and CREB in Alcohol-Induced Microglia P2X4R Receptor Expression. Alcohol Alcohol 2016; 51:647-654. [PMID: 26946194 PMCID: PMC5091293 DOI: 10.1093/alcalc/agw009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 02/05/2016] [Accepted: 02/09/2016] [Indexed: 12/12/2022] Open
Abstract
AIMS Previously we have demonstrated altered microglia P2X4R expression in response to alcohol and pharmacological blockade with a selective P2X4R antagonist can reverse the action, suggesting that P2X4R play a role in mediating alcohol-induced effects on microglia. In the present study, we investigated the underlying signaling mediators, which may play a role in modulating P2X4R expression in microglia cells in response to alcohol. METHODS Embryonic stem cell-derived microglia (ESdM) cells were used to investigate the potential mechanisms involved in the regulation of P2X4R in response to alcohol. Selective P2X4R antagonist and kinase inhibitors were used to further corroborate the signal transduction pathway through which alcohol modulates P2X4R expression in microglia. RESULTS Alcohol (100 mM) suppressed phosphorylated AKT and ERK cascades in native ESdM cells. This alcohol-induced suppression was confirmed to be P2X4R-dependent through the use of a selective P2X4R antagonist and knockdown of P2XR4 by siRNA. Alcohol increased transcriptional activity of CREB. P2X4R antagonist blocked alcohol-induced effects on CREB, suggesting a P2X4R-mediated effect. CONCLUSION These findings provide important clues to the underlying mechanism of purinoceptors in alcohol-induced microglia immune suppression.
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Affiliation(s)
- Larisa Gofman
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA
| | - Nicole C Fernandes
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Raghava Potula
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA
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14
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Yeligar SM, Chen MM, Kovacs EJ, Sisson JH, Burnham EL, Brown LAS. Alcohol and lung injury and immunity. Alcohol 2016; 55:51-59. [PMID: 27788778 DOI: 10.1016/j.alcohol.2016.08.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 07/07/2016] [Accepted: 08/24/2016] [Indexed: 02/06/2023]
Abstract
Annually, excessive alcohol use accounts for more than $220 billion in economic costs and 80,000 deaths, making excessive alcohol use the third leading lifestyle-related cause of death in the US. Patients with an alcohol-use disorder (AUD) also have an increased susceptibility to respiratory pathogens and lung injury, including a 2-4-fold increased risk of acute respiratory distress syndrome (ARDS). This review investigates some of the potential mechanisms by which alcohol causes lung injury and impairs lung immunity. In intoxicated individuals with burn injuries, activation of the gut-liver axis drives pulmonary inflammation, thereby negatively impacting morbidity and mortality. In the lung, the upper airway is the first checkpoint to fail in microbe clearance during alcohol-induced lung immune dysfunction. Brief and prolonged alcohol exposure drive different post-translational modifications of novel proteins that control cilia function. Proteomic approaches are needed to identify novel alcohol targets and post-translational modifications in airway cilia that are involved in alcohol-dependent signal transduction pathways. When the upper airway fails to clear inhaled pathogens, they enter the alveolar space where they are primarily cleared by alveolar macrophages (AM). With chronic alcohol ingestion, oxidative stress pathways in the AMs are stimulated, thereby impairing AM immune capacity and pathogen clearance. The epidemiology of pneumococcal pneumonia and AUDs is well established, as both increased predisposition and illness severity have been reported. AUD subjects have increased susceptibility to pneumococcal pneumonia infections, which may be due to the pro-inflammatory response of AMs, leading to increased oxidative stress.
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Affiliation(s)
- Samantha M Yeligar
- Department of Medicine, Emory University and Atlanta Veterans Affairs Medical Center, Decatur, GA 30033, USA
| | - Michael M Chen
- Burn and Shock Trauma Research Institute, Alcohol Research Program, Integrative Cell Biology Program, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153, USA
| | - Elizabeth J Kovacs
- Department of Surgery, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Joseph H Sisson
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Ellen L Burnham
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Lou Ann S Brown
- Department of Pediatrics, Emory University, Atlanta, GA 30322, USA.
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15
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Shults JA, Curtis BJ, Boe DM, Ramirez L, Kovacs EJ. Ethanol intoxication prolongs post-burn pulmonary inflammation: role of alveolar macrophages. J Leukoc Biol 2016; 100:1037-1045. [PMID: 27531926 DOI: 10.1189/jlb.3ma0316-111r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 07/26/2016] [Indexed: 02/06/2023] Open
Abstract
In this study, the role and fate of AMs were examined in pulmonary inflammation after intoxication and injury. Clinical evidence has revealed that half of all burn patients brought to the emergency department are intoxicated at the time of injury. This combined insult results in amplified neutrophil accumulation and pulmonary edema, with an increased risk of lung failure and mortality, relative to either insult alone. We believe that this excessive pulmonary inflammation, which also parallels decreased lung function, is mediated in part by AMs. Restoration of lung tissue homeostasis is dependent on the eradication of neutrophils and removal of apoptotic cells, both major functions of AMs. Thirty minutes after binge ethanol intoxication, mice were anesthetized and given a 15% total body surface area dorsal scald injury. At 24 h, we found a 50% decrease in the total number of AMs (P < 0.05) and observed a proinflammatory phenotype on the remaining lung AMs. Loss of AMs paralleled a 6-fold increase in the number of TUNEL+ lung apoptotic cells (P < 0.05) and a 3.5-fold increase in the percentage of annexin V+ apoptotic cells in BAL (P < 0.05), after intoxication and injury, relative to controls. In contrast to the reduction in the number of cells, AMs from intoxicated and injured mice had a 4-fold increase in efferocytosis (P < 0.05). In summary, these data suggest that loss of AMs may delay resolution of inflammation, resulting in the pulmonary complications and elevated mortality rates observed in intoxicated and burn-injured patients.
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Affiliation(s)
- Jill A Shults
- Alcohol Research Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Burn and Shock Trauma Research Institute, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Department of Surgery, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Integrative Cell Biology Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA
| | - Brenda J Curtis
- Alcohol Research Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Burn and Shock Trauma Research Institute, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Department of Surgery, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA
| | - Devin M Boe
- Alcohol Research Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Burn and Shock Trauma Research Institute, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Department of Surgery, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Integrative Cell Biology Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA
| | - Luis Ramirez
- Alcohol Research Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Burn and Shock Trauma Research Institute, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Department of Surgery, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA
| | - Elizabeth J Kovacs
- Alcohol Research Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA; .,Burn and Shock Trauma Research Institute, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Department of Surgery, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA.,Integrative Cell Biology Program, Loyola University Chicago, Health Sciences Campus, Stritch School of Medicine, Maywood, Illinois, USA
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16
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Hoyt LR, Ather JL, Randall MJ, DePuccio DP, Landry CC, Wewers MD, Gavrilin MA, Poynter ME. Ethanol and Other Short-Chain Alcohols Inhibit NLRP3 Inflammasome Activation through Protein Tyrosine Phosphatase Stimulation. THE JOURNAL OF IMMUNOLOGY 2016; 197:1322-34. [PMID: 27421477 DOI: 10.4049/jimmunol.1600406] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 06/12/2016] [Indexed: 11/19/2022]
Abstract
Immunosuppression is a major complication of alcoholism that contributes to increased rates of opportunistic infections and sepsis in alcoholics. The NLRP3 inflammasome, a multiprotein intracellular pattern recognition receptor complex that facilitates the cleavage and secretion of the proinflammatory cytokines IL-1β and IL-18, can be inhibited by ethanol, and we sought to better understand the mechanism through which this occurs and whether chemically similar molecules exert comparable effects. We show that ethanol can specifically inhibit activation of the NLRP3 inflammasome, resulting in attenuated IL-1β and caspase-1 cleavage and secretion, as well as diminished apoptosis-associated speck-like protein containing a CARD (ASC) speck formation, without affecting potassium efflux, in a mouse macrophage cell line (J774), mouse bone marrow-derived dendritic cells, mouse neutrophils, and human PBMCs. The inhibitory effects on the Nlrp3 inflammasome were independent of γ-aminobutyric acid A receptor activation or N-methyl-d-asparate receptor inhibition but were associated with decreased oxidant production. Ethanol treatment markedly decreased cellular tyrosine phosphorylation, whereas administration of the tyrosine phosphatase inhibitor sodium orthovanadate prior to ethanol restored tyrosine phosphorylation and IL-1β secretion subsequent to ATP stimulation. Furthermore, sodium orthovanadate-induced phosphorylation of ASC Y144, necessary and sufficient for Nlrp3 inflammasome activation, and secretion of phosphorylated ASC were inhibited by ethanol. Finally, multiple alcohol-containing organic compounds exerted inhibitory effects on the Nlrp3 inflammasome, whereas 2-methylbutane (isopentane), the analogous alkane of the potent inhibitor isoamyl alcohol (isopentanol), did not. Our results demonstrate that ethanol antagonizes the NLRP3 inflammasome at an apical event in its activation through the stimulation of protein tyrosine phosphatases, an effect shared by other short-chain alcohols.
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Affiliation(s)
- Laura R Hoyt
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT 05405
| | - Jennifer L Ather
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT 05405
| | - Matthew J Randall
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT 05405
| | - Daniel P DePuccio
- Department of Chemistry, University of Vermont, Burlington, VT 05405
| | - Christopher C Landry
- Department of Chemistry, University of Vermont, Burlington, VT 05405; Cellular, Molecular, and Biomedical Sciences Graduate Program, University of Vermont, Burlington, VT 05405; and
| | - Mark D Wewers
- Pulmonary, Allergy, Critical Care and Sleep Medicine, The Dorothy M. Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH 43210
| | - Mikhail A Gavrilin
- Pulmonary, Allergy, Critical Care and Sleep Medicine, The Dorothy M. Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH 43210
| | - Matthew E Poynter
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT 05405; Cellular, Molecular, and Biomedical Sciences Graduate Program, University of Vermont, Burlington, VT 05405; and
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17
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Draberova L, Paulenda T, Halova I, Potuckova L, Bugajev V, Bambouskova M, Tumova M, Draber P. Ethanol Inhibits High-Affinity Immunoglobulin E Receptor (FcεRI) Signaling in Mast Cells by Suppressing the Function of FcεRI-Cholesterol Signalosome. PLoS One 2015; 10:e0144596. [PMID: 26658290 PMCID: PMC4686000 DOI: 10.1371/journal.pone.0144596] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 11/21/2015] [Indexed: 12/12/2022] Open
Abstract
Ethanol has multiple effects on biochemical events in a variety of cell types, including the high-affinity immunoglobulin E receptor (FcεRI) signaling in antigen-activated mast cells. However, the underlying molecular mechanism remains unknown. To get better understanding of the effect of ethanol on FcεRI-mediated signaling we examined the effect of short-term treatment with non-toxic concentrations of ethanol on FcεRI signaling events in mouse bone marrow-derived mast cells. We found that 15 min exposure to ethanol inhibited antigen-induced degranulation, calcium mobilization, expression of proinflammatory cytokine genes (tumor necrosis factor-α, interleukin-6, and interleukin-13), and formation of reactive oxygen species in a dose-dependent manner. Removal of cellular cholesterol with methyl-β-cyclodextrin had a similar effect and potentiated some of the inhibitory effects of ethanol. In contrast, exposure of the cells to cholesterol-saturated methyl-β-cyclodextrin abolished in part the inhibitory effect of ethanol on calcium response and production of reactive oxygen species, supporting lipid-centric theories of ethanol action on the earliest stages of mast cell signaling. Further studies showed that exposure to ethanol and/or removal of cholesterol inhibited early FcεRI activation events, including tyrosine phosphorylation of the FcεRI β and γ subunits, SYK kinases, LAT adaptor protein, phospholipase Cγ, STAT5, and AKT and internalization of aggregated FcεRI. Interestingly, ethanol alone, and particularly in combination with methyl-β-cyclodextrin, enhanced phosphorylation of negative regulatory tyrosine 507 of LYN kinase. Finally, we found that ethanol reduced passive cutaneous anaphylactic reaction in mice, suggesting that ethanol also inhibits FcεRI signaling under in vivo conditions. The combined data indicate that ethanol interferes with early antigen-induced signaling events in mast cells by suppressing the function of FcεRI-cholesterol signalosomes at the plasma membrane.
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Affiliation(s)
- Lubica Draberova
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- * E-mail: (LD); (PD)
| | - Tomas Paulenda
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Ivana Halova
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Lucie Potuckova
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Viktor Bugajev
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Monika Bambouskova
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Magda Tumova
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Petr Draber
- Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- * E-mail: (LD); (PD)
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18
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Saha B, Momen-Heravi F, Kodys K, Szabo G. MicroRNA Cargo of Extracellular Vesicles from Alcohol-exposed Monocytes Signals Naive Monocytes to Differentiate into M2 Macrophages. J Biol Chem 2015; 291:149-59. [PMID: 26527689 DOI: 10.1074/jbc.m115.694133] [Citation(s) in RCA: 167] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Indexed: 12/19/2022] Open
Abstract
Membrane-coated extracellular vesicles (EVs) released by cells can serve as vehicles for delivery of biological materials and signals. Recently, we demonstrated that alcohol-treated hepatocytes cross-talk with immune cells via exosomes containing microRNA (miRNAs). Here, we hypothesized that alcohol-exposed monocytes can communicate with naive monocytes via EVs. We observed increased numbers of EVs, mostly exosomes, secreted by primary human monocytes and THP-1 monocytic cells in the presence of alcohol in a concentration- and time-dependent manner. EVs derived from alcohol-treated monocytes stimulated naive monocytes to polarize into M2 macrophages as indicated by increased surface expression of CD68 (macrophage marker), M2 markers (CD206 (mannose receptor) and CD163 (scavenger receptor)), secretion of IL-10, and TGFβ and increased phagocytic activity. miRNA profiling of the EVs derived from alcohol-treated THP-1 monocytes revealed high expression of the M2-polarizing miRNA, miR-27a. Treatment of naive monocytes with control EVs overexpressing miR-27a reproduced the effect of EVs from alcohol-treated monocytes on naive monocytes and induced M2 polarization, suggesting that the effect of alcohol EVs was mediated by miR-27a. We found that miR-27a modulated the process of phagocytosis by targeting CD206 expression on monocytes. Importantly, analysis of circulating EVs from plasma of alcoholic hepatitis patients revealed increased numbers of EVs that contained high levels of miR-27a as compared with healthy controls. Our results demonstrate the following: first, alcohol increases EV production in monocytes; second, alcohol-exposed monocytes communicate with naive monocytes via EVs; and third, miR-27a cargo in monocyte-derived EVs can program naive monocytes to polarize into M2 macrophages.
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Affiliation(s)
- Banishree Saha
- From the Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Fatemeh Momen-Heravi
- From the Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Karen Kodys
- From the Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Gyongyi Szabo
- From the Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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19
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Shults JA, Curtis BJ, Chen MM, O'Halloran EB, Ramirez L, Kovacs EJ. Impaired respiratory function and heightened pulmonary inflammation in episodic binge ethanol intoxication and burn injury. Alcohol 2015; 49:713-20. [PMID: 26364264 DOI: 10.1016/j.alcohol.2015.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/18/2015] [Accepted: 06/19/2015] [Indexed: 01/25/2023]
Abstract
Clinical data indicate that cutaneous burn injuries covering greater than 10% of the total body surface area are associated with significant morbidity and mortality, in which pulmonary complications, including acute respiratory distress syndrome (ARDS), contribute to nearly half of all patient deaths. Approximately 50% of burn patients are intoxicated at the time of hospital admission, which increases days on ventilators by 3-fold, and doubles the length of hospitalization, compared to non-intoxicated burn patients. The most common drinking pattern in the United States is binge drinking, where an individual rapidly consumes alcoholic beverages (4 for women, 5 for men) in 2 h. An estimated 38 million Americans binge drink, often several times per month. Experimental data demonstrate that a single binge-ethanol exposure, prior to scald injury, impairs innate and adaptive immune responses, thereby enhancing infection susceptibility and amplifying pulmonary inflammation, neutrophil infiltration, and edema, and is associated with increased mortality. Since these characteristics are similar to those observed in ARDS burn patients, our study objective was to determine whether ethanol intoxication and burn injury and the subsequent pulmonary congestion affect physiological parameters of lung function, using non-invasive and unrestrained plethysmography in a murine model system. Furthermore, to mirror young adult binge-drinking patterns, and to determine the effect of multiple ethanol exposures on pulmonary inflammation, we utilized an episodic binge-ethanol exposure regimen, where mice were exposed to ethanol for a total of 6 days (3 days ethanol, 4 days rest, 3 days ethanol) prior to burn injury. Our analyses demonstrate mice exposed to episodic binge ethanol and burn injury have higher mortality, increased pulmonary congestion and neutrophil infiltration, elevated neutrophil chemoattractants, and respiratory dysfunction, compared to burn or ethanol intoxication alone. Overall, our study identifies plethysmography as a useful tool for characterizing respiratory function in a murine burn model and for future identification of therapeutic compounds capable of restoring pulmonary functionality.
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20
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Afshar M, Richards S, Mann D, Cross A, Smith GB, Netzer G, Kovacs E, Hasday J. Acute immunomodulatory effects of binge alcohol ingestion. Alcohol 2015; 49:57-64. [PMID: 25572859 DOI: 10.1016/j.alcohol.2014.10.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 09/30/2014] [Accepted: 10/08/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Blood alcohol is present in a third of trauma patients and has been associated with organ dysfunction. In both human studies and in animal models, it is clear that alcohol intoxication exerts immunomodulatory effects several hours to days after exposure, when blood alcohol is no longer detectable. The early immunomodulatory effects of alcohol while blood alcohol is still elevated are not well understood. METHODS Human volunteers achieved binge alcohol intoxication after high-dose alcohol consumption. Blood was collected for analysis prior to alcohol ingestion, and 20 min, 2 h, and 5 h after alcohol ingestion. Flow cytometry was performed on isolated peripheral blood mononuclear cells, and cytokine generation in whole blood was measured by enzyme-linked immunosorbent assay (ELISA) after 24-h stimulation with lipopolysaccharide (LPS) and phytohemagglutinin-M (PHA) stimulation. RESULTS An early pro-inflammatory state was evident at 20 min when blood alcohol levels were ∼130 mg/dL, which was characterized by an increase in total circulating leukocytes, monocytes, and natural killer cells. During this time, a transient increase in LPS-induced tumor necrosis factor (TNF)-α levels and enhanced LPS sensitivity occurred. At 2 and 5 h post-alcohol binge, an anti-inflammatory state was shown with reduced numbers of circulating monocytes and natural killer cells, attenuated LPS-induced interleukin (IL)-1β levels, and a trend toward increased interleukin (IL)-10 levels. CONCLUSIONS A single episode of binge alcohol intoxication exerted effects on the immune system that caused an early and transient pro-inflammatory state followed by an anti-inflammatory state.
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Gofman L, Cenna JM, Potula R. P2X4 receptor regulates alcohol-induced responses in microglia. J Neuroimmune Pharmacol 2014; 9:668-78. [PMID: 25135400 DOI: 10.1007/s11481-014-9559-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 07/28/2014] [Indexed: 12/18/2022]
Abstract
Mounting evidence indicates that alcohol-induced neuropathology may result from multicellular responses in which microglia cells play a prominent role. Purinergic receptor signaling plays a key role in regulating microglial function and, more importantly, mediates alcohol-induced effects. Our findings demonstrate that alcohol increases expression of P2X4 receptor (P2X4R), which alters the function of microglia, including calcium mobilization, migration and phagocytosis. Our results show a significant up-regulation of P2X4 gene expression as analyzed by real-time qPCR (***p < 0.002) and protein expression as analyzed by flow cytometry (**p < 0.004) in embryonic stem cell-derived microglial cells (ESdM) after 48 hours of alcohol treatment, as compared to untreated controls. Calcium mobilization in ethanol treated ESdM cells was found to be P2X4R dependent using 5-BDBD, a P2X4R selective antagonist. Alcohol decreased migration of microglia towards fractalkine (CX3CL1) by 75 % following 48 h of treatment compared to control (***p < 0.001). CX3CL1-dependent migration was confirmed to be P2X4 receptor-dependent using the antagonist 5-BDBD, which reversed the effects as compared to alcohol alone (***p < 0.001). Similarly, 48 h of alcohol treatment significantly decreased phagocytosis of microglia by 15 % compared to control (*p < 0.05). 5-BDBD pre-treatment prior to alcohol treatment significantly increased microglial phagocytosis (***p < 0.001). Blocking P2X4R signaling with 5-BDBD decreased the level of calcium mobilization compared to ethanol treatment alone. These findings demonstrate that P2X4 receptor may play a role in modulating microglial function in the context of alcohol abuse.
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Affiliation(s)
- Larisa Gofman
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, 3500 N. Broad Street, MERB 845A, Philadelphia, PA, 19140, USA
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Asplund MB, Coelho C, Cordero RJB, Martinez LR. Alcohol impairs J774.16 macrophage-like cell antimicrobial functions in Acinetobacter baumannii infection. Virulence 2013; 4:467-72. [PMID: 23863607 DOI: 10.4161/viru.25641] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Acinetobacter baumannii (Ab) is a common cause of community-acquired pneumonia (CAP) in chronic alcoholics in tropical and sub-tropical climates and associated with a > 50% mortality rate. We demonstrated that exposure of J774.16 macrophage-like cells to physiological alcohol (EtOH) concentrations decreased phagocytosis and killing of Ab. EtOH-mediated macrophage phagocytosis dysfunction may be associated with reduced expression of GTPase-RhoA, a key regulator of the actin polymerization signaling cascade. EtOH inhibited nitric oxide (NO) generation via inducible NO-synthase inactivation, which enhanced Ab survival within macrophages. Additionally, EtOH alters cytokine production resulting in a dysregulated immune response. This study is a proof of principle which establishes that EtOH might exacerbate Ab infection and be an important factor enhancing CAP in individuals at risk.
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Affiliation(s)
- Melissa B Asplund
- Department of Biomedical Sciences, Long Island University-Post, Brookville, NY, USA
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Pál L, Árnyas EM, Tóth B, Ádám B, Rácz G, Ádány R, McKee M, Szűcs S. Aliphatic alcohol contaminants of illegally produced spirits inhibit phagocytosis by human granulocytes. Immunopharmacol Immunotoxicol 2013; 35:251-6. [DOI: 10.3109/08923973.2012.759962] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Brubaker AL, Rendon JL, Ramirez L, Choudhry MA, Kovacs EJ. Reduced neutrophil chemotaxis and infiltration contributes to delayed resolution of cutaneous wound infection with advanced age. THE JOURNAL OF IMMUNOLOGY 2013; 190:1746-57. [PMID: 23319733 DOI: 10.4049/jimmunol.1201213] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Advanced age is associated with alterations in innate and adaptive immune responses, which contribute to an increased risk of infection in elderly patients. Coupled with this immune dysfunction, elderly patients demonstrate impaired wound healing with elevated rates of wound dehiscence and chronic wounds. To evaluate how advanced age alters the host immune response to cutaneous wound infection, we developed a murine model of cutaneous Staphylococcus aureus wound infection in young (3-4 mo) and aged (18-20 mo) BALB/c mice. Aged mice exhibit increased bacterial colonization and delayed wound closure over time compared with young mice. These differences were not attributed to alterations in wound neutrophil or macrophage TLR2 or FcγRIII expression, or age-related changes in phagocytic potential and bactericidal activity. To evaluate the role of chemotaxis in our model, we first examined in vivo chemotaxis in the absence of wound injury to KC, a neutrophil chemokine. In response to a s.c. injection of KC, aged mice recruited fewer neutrophils at increasing doses of KC compared with young mice. This paralleled our model of wound infection, where diminished neutrophil and macrophage recruitment was observed in aged mice relative to young mice despite equivalent levels of KC, MIP-2, and MCP-1 chemokine levels at the wound site. This reduced leukocyte accumulation was also associated with lower levels of ICAM-1 in wounds from aged mice at early time points. These age-mediated defects in early neutrophil recruitment may alter the dynamics of the inflammatory phase of wound healing, impacting macrophage recruitment, bacterial clearance, and wound closure.
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Affiliation(s)
- Aleah L Brubaker
- Burn and Shock Trauma Institute, Loyola University Chicago Health Sciences Division, Maywood, IL 60153, USA
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