1
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Tran N, Mills EL. Redox regulation of macrophages. Redox Biol 2024; 72:103123. [PMID: 38615489 PMCID: PMC11026845 DOI: 10.1016/j.redox.2024.103123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/26/2024] [Accepted: 03/11/2024] [Indexed: 04/16/2024] Open
Abstract
Redox signaling, a mode of signal transduction that involves the transfer of electrons from a nucleophilic to electrophilic molecule, has emerged as an essential regulator of inflammatory macrophages. Redox reactions are driven by reactive oxygen/nitrogen species (ROS and RNS) and redox-sensitive metabolites such as fumarate and itaconate, which can post-translationally modify specific cysteine residues in target proteins. In the past decade our understanding of how ROS, RNS, and redox-sensitive metabolites control macrophage function has expanded dramatically. In this review, we discuss the latest evidence of how ROS, RNS, and metabolites regulate macrophage function and how this is dysregulated with disease. We highlight the key tools to assess redox signaling and important questions that remain.
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Affiliation(s)
- Nhien Tran
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Immunology, Harvard Medical School, Boston, MA, USA
| | - Evanna L Mills
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Immunology, Harvard Medical School, Boston, MA, USA.
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2
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Mollace R, Scarano F, Bava I, Carresi C, Maiuolo J, Tavernese A, Gliozzi M, Musolino V, Muscoli S, Palma E, Muscoli C, Salvemini D, Federici M, Macrì R, Mollace V. Modulation of the nitric oxide/cGMP pathway in cardiac contraction and relaxation: Potential role in heart failure treatment. Pharmacol Res 2023; 196:106931. [PMID: 37722519 DOI: 10.1016/j.phrs.2023.106931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/09/2023] [Accepted: 09/15/2023] [Indexed: 09/20/2023]
Abstract
Evidence exists that heart failure (HF) has an overall impact of 1-2 % in the global population being often associated with comorbidities that contribute to increased disease prevalence, hospitalization, and mortality. Recent advances in pharmacological approaches have significantly improved clinical outcomes for patients with vascular injury and HF. Nevertheless, there remains an unmet need to clarify the crucial role of nitric oxide/cyclic guanosine 3',5'-monophosphate (NO/cGMP) signalling in cardiac contraction and relaxation, to better identify the key mechanisms involved in the pathophysiology of myocardial dysfunction both with reduced (HFrEF) as well as preserved ejection fraction (HFpEF). Indeed, NO signalling plays a crucial role in cardiovascular homeostasis and its dysregulation induces a significant increase in oxidative and nitrosative stress, producing anatomical and physiological cardiac alterations that can lead to heart failure. The present review aims to examine the molecular mechanisms involved in the bioavailability of NO and its modulation of downstream pathways. In particular, we focus on the main therapeutic targets and emphasize the recent evidence of preclinical and clinical studies, describing the different emerging therapeutic strategies developed to counteract NO impaired signalling and cardiovascular disease (CVD) development.
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Affiliation(s)
- Rocco Mollace
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy; Department of Systems Medicine, University of Rome Tor Vergata, Italy
| | - Federica Scarano
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Irene Bava
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Cristina Carresi
- Veterinary Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Jessica Maiuolo
- Pharmaceutical Biology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Annamaria Tavernese
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Micaela Gliozzi
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Vincenzo Musolino
- Pharmaceutical Biology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Saverio Muscoli
- Division of Cardiology, Foundation PTV Polyclinic Tor Vergata, Rome 00133, Italy
| | - Ernesto Palma
- Veterinary Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Carolina Muscoli
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy
| | - Daniela Salvemini
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Massimo Federici
- Department of Systems Medicine, University of Rome Tor Vergata, Italy
| | - Roberta Macrì
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy.
| | - Vincenzo Mollace
- Pharmacology Laboratory, Institute of Research for Food Safety and Health IRC-FSH, Department of Health Sciences, University Magna Graecia of Catanzaro, Catanzaro 88100, Italy; Renato Dulbecco Institute, Lamezia Terme, Catanzaro 88046, Italy.
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3
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Girotti AW, Bazak J, Korytowski W. Pro-Tumor Activity of Endogenous Nitric Oxide in Anti-Tumor Photodynamic Therapy: Recently Recognized Bystander Effects. Int J Mol Sci 2023; 24:11559. [PMID: 37511317 PMCID: PMC10380283 DOI: 10.3390/ijms241411559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Various studies have revealed that several cancer cell types can upregulate inducible nitric oxide synthase (iNOS) and iNOS-derived nitric oxide (NO) after moderate photodynamic treatment (PDT) sensitized by 5-aminolevulinic acid (ALA)-induced protoporphyrin-IX. As will be discussed, the NO signaled cell resistance to photokilling as well as greater growth and migratory aggressiveness of surviving cells. On this basis, it was predicted that diffusible NO from PDT-targeted cells in a tumor might enhance the growth, migration, and invasiveness of non- or poorly PDT-targeted bystander cells. This was tested using a novel approach in which ALA-PDT-targeted cancer cells on a culture dish were initially segregated from non-targeted bystander cells of the same type via impermeable silicone-rimmed rings. Several hours after LED irradiation, the rings were removed, and both cell populations were analyzed in the dark for various responses. After a moderate extent of targeted cell killing (~25%), bystander proliferation and migration were evaluated, and both were found to be significantly enhanced. Enhancement correlated with iNOS/NO upregulation in surviving PDT-targeted cancer cells in the following cell type order: PC3 > MDA-MB-231 > U87 > BLM. If occurring in an actual PDT-challenged tumor, such bystander effects might compromise treatment efficacy by stimulating tumor growth and/or metastatic dissemination. Mitigation of these and other negative NO effects using pharmacologic adjuvants that either inhibit iNOS transcription or enzymatic activity will be discussed.
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Affiliation(s)
- Albert W Girotti
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jerzy Bazak
- Department of Biophysics, Jagiellonian University, 31-007 Krakow, Poland
| | - Witold Korytowski
- Department of Biophysics, Jagiellonian University, 31-007 Krakow, Poland
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Afonso GJM, Cavaleiro C, Valero J, Mota SI, Ferreiro E. Recent Advances in Extracellular Vesicles in Amyotrophic Lateral Sclerosis and Emergent Perspectives. Cells 2023; 12:1763. [PMID: 37443797 PMCID: PMC10340215 DOI: 10.3390/cells12131763] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/22/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a severe and incurable neurodegenerative disease characterized by the progressive death of motor neurons, leading to paralysis and death. It is a rare disease characterized by high patient-to-patient heterogeneity, which makes its study arduous and complex. Extracellular vesicles (EVs) have emerged as important players in the development of ALS. Thus, ALS phenotype-expressing cells can spread their abnormal bioactive cargo through the secretion of EVs, even in distant tissues. Importantly, owing to their nature and composition, EVs' formation and cargo can be exploited for better comprehension of this elusive disease and identification of novel biomarkers, as well as for potential therapeutic applications, such as those based on stem cell-derived exosomes. This review highlights recent advances in the identification of the role of EVs in ALS etiopathology and how EVs can be promising new therapeutic strategies.
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Affiliation(s)
- Gonçalo J. M. Afonso
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (G.J.M.A.); (C.C.)
- Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- III-Institute of Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Carla Cavaleiro
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (G.J.M.A.); (C.C.)
- Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- III-Institute of Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Jorge Valero
- Instituto de Neurociencias de Castilla y León, University of Salamanca, 37007 Salamanca, Spain;
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain
- Department of Cell Biology and Pathology, University of Salamanca, 37007 Salamanca, Spain
| | - Sandra I. Mota
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (G.J.M.A.); (C.C.)
- Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- III-Institute of Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Elisabete Ferreiro
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (G.J.M.A.); (C.C.)
- Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- III-Institute of Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
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5
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Serreli G, Deiana M. Role of Dietary Polyphenols in the Activity and Expression of Nitric Oxide Synthases: A Review. Antioxidants (Basel) 2023; 12:antiox12010147. [PMID: 36671009 PMCID: PMC9854440 DOI: 10.3390/antiox12010147] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/10/2023] Open
Abstract
Nitric oxide (NO) plays several key roles in the functionality of an organism, and it is usually released in numerous organs and tissues. There are mainly three isoforms of the enzyme that produce NO starting from the metabolism of arginine, namely endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and neuronal nitric oxide synthase (nNOS). The expression and activity of these isoforms depends on the activation/deactivation of different signaling pathways at an intracellular level following different physiological and pathological stimuli. Compounds of natural origin such as polyphenols, which are obtainable through diet, have been widely studied in recent years in in vivo and in vitro investigations for their ability to induce or inhibit NO release, depending on the tissue. In this review, we aim to disclose the scientific evidence relating to the activity of the main dietary polyphenols in the modulation of the intracellular pathways involved in the expression and/or functionality of the NOS isoforms.
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Tahri-Joutey M, Saih FE, El Kebbaj R, Gondcaille C, Vamecq J, Latruffe N, Lizard G, Savary S, Nasser B, Cherkaoui-Malki M, Andreoletti P. Protective Effect of Nopal Cactus (Opuntia ficus-indica) Seed Oil against Short-Term Lipopolysaccharides-Induced Inflammation and Peroxisomal Functions Dysregulation in Mouse Brain and Liver. Int J Mol Sci 2022; 23:ijms231911849. [PMID: 36233157 PMCID: PMC9569537 DOI: 10.3390/ijms231911849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/28/2022] [Accepted: 09/30/2022] [Indexed: 11/16/2022] Open
Abstract
Exposure to endotoxins (lipopolysaccharides, LPS) may lead to a potent inflammatory cytokine response and a severe impairment of metabolism, causing tissue injury. The protective effect provided by cactus seed oil (CSO), from Opuntia ficus-indica, was evaluated against LPS-induced inflammation, dysregulation of peroxisomal antioxidant, and β-oxidation activities in the brain and the liver. In both tissues, a short-term LPS exposure increased the proinflammatory interleukine-1β (Il-1β), inducible Nitroxide synthase (iNos), and Interleukine-6 (Il-6). In the brain, CSO action reduced only LPS-induced iNos expression, while in the liver, CSO attenuated mainly the hepatic Il-1β and Il-6. Regarding the peroxisomal antioxidative functions, CSO treatment (as Olive oil (OO) or Colza oil (CO) treatment) induced the hepatic peroxisomal Cat gene. Paradoxically, we showed that CSO, as well as OO or CO, treatment can timely induce catalase activity or prevent its induction by LPS, respectively, in both brain and liver tissues. On the other hand, CSO (as CO) pretreatment prevented the LPS-associated Acox1 gene and activity decreases in the liver. Collectively, CSO showed efficient neuroprotective and hepato-protective effects against LPS, by maintaining the brain peroxisomal antioxidant enzyme activities of catalase and glutathione peroxidase, and by restoring hepatic peroxisomal antioxidant and β-oxidative capacities.
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Affiliation(s)
- Mounia Tahri-Joutey
- Laboratoire Biochimie, Neurosciences, Ressources Naturelles et Environnement, Faculté des Sciences et Techniques, Université Hassan I, BP577, Settat 26000, Morocco
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Fatima-Ezzahra Saih
- Laboratoire Biochimie, Neurosciences, Ressources Naturelles et Environnement, Faculté des Sciences et Techniques, Université Hassan I, BP577, Settat 26000, Morocco
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Riad El Kebbaj
- Laboratoire Biochimie, Neurosciences, Ressources Naturelles et Environnement, Faculté des Sciences et Techniques, Université Hassan I, BP577, Settat 26000, Morocco
- Laboratory of Health Sciences and Technologies, Higher Institute of Health Sciences, Hassan First University, Settat 26000, Morocco
| | - Catherine Gondcaille
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Joseph Vamecq
- INSERM and HMNO, CBP, CHRU Lille, 59000 Lille and RADEME EA 7364, Faculté de Médecine, Université de Lille 2, 59045 Lille, France
| | - Norbert Latruffe
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Gérard Lizard
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Stéphane Savary
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
| | - Boubker Nasser
- Laboratoire Biochimie, Neurosciences, Ressources Naturelles et Environnement, Faculté des Sciences et Techniques, Université Hassan I, BP577, Settat 26000, Morocco
| | - Mustapha Cherkaoui-Malki
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
- Correspondence: ; Tel.: +33-380-39-62-37
| | - Pierre Andreoletti
- Laboratoire Bio-PeroxIL EA7270, University Bourgogne Franche-Comté, 6 Bd Gabriel, 21000 Dijon, France
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Martin TM, Burke SJ, Batdorf HM, Burk DH, Ghosh S, Dupuy SD, Karlstad MD, Collier JJ. ICAM-1 Abundance Is Increased in Pancreatic Islets of Hyperglycemic Female NOD Mice and Is Rapidly Upregulated by NF-κB in Pancreatic β-Cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 209:569-581. [PMID: 35851539 PMCID: PMC9845432 DOI: 10.4049/jimmunol.2200065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 05/24/2022] [Indexed: 01/04/2023]
Abstract
Type 1 diabetes (T1D) is classified as an autoimmune disease where pancreatic β-cells are specifically targeted by cells of the immune system. The molecular mechanisms underlying this process are not completely understood. Herein, we identified that the Icam1 gene and ICAM-1 protein were selectively elevated in female NOD mice relative to male mice, fitting with the sexual dimorphism of diabetes onset in this key mouse model of T1D. In addition, ICAM-1 abundance was greater in hyperglycemic female NOD mice than in age-matched normoglycemic female NOD mice. Moreover, we discovered that the Icam1 gene was rapidly upregulated in response to IL-1β in mouse, rat, and human islets and in 832/13 rat insulinoma cells. This early temporal genetic regulation requires key components of the NF-κB pathway and was associated with rapid recruitment of the p65 transcriptional subunit of NF-κB to corresponding κB elements within the Icam1 gene promoter. In addition, RNA polymerase II recruitment to the Icam1 gene promoter in response to IL-1β was consistent with p65 occupancy at κB elements, histone chemical modifications, and increased mRNA abundance. Thus, we conclude that β-cells undergo rapid genetic reprogramming by IL-1β to enhance expression of the Icam1 gene and that elevations in ICAM-1 are associated with hyperglycemia in NOD mice. These findings are highly relevant to, and highlight the importance of, pancreatic β-cell communication with the immune system. Collectively, these observations reveal a portion of the complex molecular events associated with onset and progression of T1D.
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Affiliation(s)
- Thomas M. Martin
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center Baton Rouge LA 70808 USA
| | - Susan J. Burke
- Laboratory of Immunogenetics, Pennington Biomedical Research Center Baton Rouge LA 70808 USA
| | - Heidi M. Batdorf
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center Baton Rouge LA 70808 USA
| | - David H. Burk
- Cell Biology and Bioimaging Core, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Sujoy Ghosh
- Laboratory of Computational Biology, Pennington Biomedical Research Center, Baton Rouge, LA, United States
- Centre for Computational Biology and Program in Cardiovascular and Metabolic Disorders, Duke NUS Medical School, Singapore
| | - Samuel D. Dupuy
- Department of Surgery, University of Tennessee Health Science Center, Knoxville, TN, 37920, USA
| | - Michael D. Karlstad
- Department of Surgery, University of Tennessee Health Science Center, Knoxville, TN, 37920, USA
| | - J. Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center Baton Rouge LA 70808 USA
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Pedersen SS, Prause M, Williams K, Barrès R, Billestrup N. Butyrate inhibits IL-1β-induced inflammatory gene expression by suppression of NF-κB activity in pancreatic beta cells. J Biol Chem 2022; 298:102312. [PMID: 35921894 PMCID: PMC9428856 DOI: 10.1016/j.jbc.2022.102312] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 11/05/2022] Open
Abstract
Cytokine-induced beta cell dysfunction is a hallmark of type 2 diabetes (T2D). Chronic exposure of beta cells to inflammatory cytokines affects gene expression and impairs insulin secretion. Thus, identification of anti-inflammatory factors that preserve beta cell function represents an opportunity to prevent or treat T2D. Butyrate is a gut microbial metabolite with anti-inflammatory properties for which we recently showed a role in preventing interleukin-1β (IL-1β)-induced beta cell dysfunction, but how prevention is accomplished is unclear. Here, we investigated the mechanisms by which butyrate exerts anti-inflammatory activity in beta cells. We exposed mouse islets and INS-1E cells to a low dose of IL-1β and/or butyrate and measured expression of inflammatory genes and nitric oxide (NO) production. Additionally, we explored the molecular mechanisms underlying butyrate activity by dissecting the activation of the nuclear factor-κB (NF-κB) pathway. We found that butyrate suppressed IL-1β-induced expression of inflammatory genes, such as Nos2, Cxcl1, and Ptgs2, and reduced NO production. Butyrate did not inhibit IκBα degradation nor NF-κB p65 nuclear translocation. Furthermore, butyrate did not affect binding of NF-κB p65 to target sequences in synthetic DNA but inhibited NF-κB p65 binding and RNA polymerase II recruitment to inflammatory gene promoters in the context of native DNA. We found this was concurrent with increased acetylation of NF-κB p65 and histone H4, suggesting butyrate affects NF-κB activity via inhibition of histone deacetylases. Together, our results show butyrate inhibits IL-1β-induced inflammatory gene expression and NO production through suppression of NF-κB activation and thereby possibly preserves beta cell function.
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Smoak P, Burke SJ, Martin TM, Batdorf HM, Floyd ZE, Collier JJ. Artemisia dracunculus L. Ethanolic Extract and an Isolated Component, DMC2, Ameliorate Inflammatory Signaling in Pancreatic β-Cells via Inhibition of p38 MAPK. Biomolecules 2022; 12:biom12050708. [PMID: 35625635 PMCID: PMC9139089 DOI: 10.3390/biom12050708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/09/2022] [Accepted: 05/13/2022] [Indexed: 02/01/2023] Open
Abstract
Non-resolving pancreatic islet inflammation is widely viewed as a contributor to decreases in β-cell mass and function that occur in both Type 1 and Type 2 diabetes. Therefore, strategies aimed at reducing or eliminating pathological inflammation would be useful to protect islet β-cells. Herein, we described the use of 2′,4′-dihydroxy-4-methoxydihydrochalcone (DMC2), a bioactive molecule isolated from an ethanolic extract of Artemisia dracunculus L., as a novel anti-inflammatory agent. The ethanolic extract, termed PMI 5011, reduced IL-1β-mediated NF-κB activity. DMC2 retained this ability, indicating this compound as the likely source of anti-inflammatory activity within the overall PMI 5011 extract. We further examined NF-κB activity using promoter-luciferase reporter constructs, Western blots, mRNA abundance, and protein secretion. Specifically, we found that PMI 5011 and DMC2 each reduced the ability of IL-1β to promote increases in the expression of the Ccl2 and Ccl20 genes. These genes encode proteins that promote immune cell recruitment and are secreted by β-cells in response to IL-1β. Phosphorylation of IκBα and the p65 subunit of NF-κB were not reduced by either PMI 5011 or DMC2; however, phosphorylation of p38 MAPK was blunted in the presence of DMC2. Finally, we observed that while PMI 5011 impaired glucose-stimulated insulin secretion, insulin output was preserved in the presence of DMC2. In conclusion, PMI 5011 and DMC2 reduced inflammation, but only DMC2 did so with the preservation of glucose-stimulated insulin secretion.
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Affiliation(s)
- Peter Smoak
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA; (P.S.); (T.M.M.); (H.M.B.)
| | - Susan J. Burke
- Laboratory of Immunogenetics, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA;
| | - Thomas M. Martin
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA; (P.S.); (T.M.M.); (H.M.B.)
| | - Heidi M. Batdorf
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA; (P.S.); (T.M.M.); (H.M.B.)
| | - Z. Elizabeth Floyd
- Laboratory of Ubitquitin Biology, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA;
| | - J. Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA; (P.S.); (T.M.M.); (H.M.B.)
- Correspondence:
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10
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Nord JA, Wynia-Smith SL, Gehant AL, Jones Lipinski RA, Naatz A, Rioja I, Prinjha RK, Corbett JA, Smith BC. N-terminal BET bromodomain inhibitors disrupt a BRD4-p65 interaction and reduce inducible nitric oxide synthase transcription in pancreatic β-cells. Front Endocrinol (Lausanne) 2022; 13:923925. [PMID: 36176467 PMCID: PMC9513428 DOI: 10.3389/fendo.2022.923925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 08/19/2022] [Indexed: 02/02/2023] Open
Abstract
Chronic inflammation of pancreatic islets is a key driver of β-cell damage that can lead to autoreactivity and the eventual onset of autoimmune diabetes (T1D). In the islet, elevated levels of proinflammatory cytokines induce the transcription of the inducible nitric oxide synthase (iNOS) gene, NOS2, ultimately resulting in increased nitric oxide (NO). Excessive or prolonged exposure to NO causes β-cell dysfunction and failure associated with defects in mitochondrial respiration. Recent studies showed that inhibition of the bromodomain and extraterminal domain (BET) family of proteins, a druggable class of epigenetic reader proteins, prevents the onset and progression of T1D in the non-obese diabetic mouse model. We hypothesized that BET proteins co-activate transcription of cytokine-induced inflammatory gene targets in β-cells and that selective, chemotherapeutic inhibition of BET bromodomains could reduce such transcription. Here, we investigated the ability of BET bromodomain small molecule inhibitors to reduce the β-cell response to the proinflammatory cytokine interleukin 1 beta (IL-1β). BET bromodomain inhibition attenuated IL-1β-induced transcription of the inflammatory mediator NOS2 and consequent iNOS protein and NO production. Reduced NOS2 transcription is consistent with inhibition of NF-κB facilitated by disrupting the interaction of a single BET family member, BRD4, with the NF-κB subunit, p65. Using recently reported selective inhibitors of the first and second BET bromodomains, inhibition of only the first bromodomain was necessary to reduce the interaction of BRD4 with p65 in β-cells. Moreover, inhibition of the first bromodomain was sufficient to mitigate IL-1β-driven decreases in mitochondrial oxygen consumption rates and β-cell viability. By identifying a role for the interaction between BRD4 and p65 in controlling the response of β-cells to proinflammatory cytokines, we provide mechanistic information on how BET bromodomain inhibition can decrease inflammation. These studies also support the potential therapeutic application of more selective BET bromodomain inhibitors in attenuating β-cell inflammation.
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Affiliation(s)
- Joshua A. Nord
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Sarah L. Wynia-Smith
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Alyssa L. Gehant
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | | | - Aaron Naatz
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Inmaculada Rioja
- Immuno-Epigenetics, Immunology Research Unit, GlaxoSmithKline Medicines Research Centre, Stevenage, United Kingdom
| | - Rab K. Prinjha
- Immuno-Epigenetics, Immunology Research Unit, GlaxoSmithKline Medicines Research Centre, Stevenage, United Kingdom
| | - John A. Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Brian C. Smith
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
- *Correspondence: Brian C. Smith,
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Siraj MA, Islam Howlader MS, Islam MA, Irin T, Simal-Gandara J. Regulation of the redox signaling and inflammation by Terminalia myriocarpa leaves and the predictive interactions of it's major metabolites with iNOS and NF-ĸB. JOURNAL OF ETHNOPHARMACOLOGY 2021; 280:114459. [PMID: 34343646 DOI: 10.1016/j.jep.2021.114459] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 07/06/2021] [Accepted: 07/24/2021] [Indexed: 06/13/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The present study was designed to investigate the regulation of the redox signaling and inflammation by ethanolic leaf extract of Terminalia myriocarpaVan Heurck & Müller (ETM), inspired by the reported antioxidant potential of the plant bark and the anti-edema effect of the same genus. MATERIALS AND METHODS HPLC-DAD dereplication study was conducted to detect the major polyphenolic secondary metabolites. In-vitro DPPH free radical scavenging assay, nitric oxide (NO) scavenging assay, Fe2+ ion chelating ability assay and reducing power assay were conducted to evaluate the antioxidant capacity. The molecular mechanism of anti-inflammation was investigated via assessing the NO and NF-ĸB inhibiting properties in different cell lines. In-vivo carrageenan and histamine-induced edema tests were conducted using established animal models. Pro-inflammatory proteins iNOS and NF-κB were docked against the major metabolites of ETM in the in-silico study. RESULTS HPLC dereplication analysis revealed the presence of considerable amount of ellagic acid, where methyl-(S)-flavogallonate was previously reported in T. myriocarpa. Significant antioxidant activity was found in every in- vitro redox assay conducted. NO was reduced in RAW 264.7 cells, showing 83.67 ± 4.18% inhibitory activity at the highest tested concentration. TNF-α induced NF-κB was also observed to be reduced in 293/NF-кB-luc cells with an inhibitory activity of 66.23 ± 0.81% at the highest dose tested. In-vivo carrageenan-induced edema test demonstrated significant anti-inflammatory activity (p < 0.05; p < 0.01) at both doses of 250 and 500 mg/kg with 60.10% highest reduction in rat paw volume. Using same doses, histamine-induced edema test exhibited mentionable anti-inflammatory potential (p < 0.05; p < 0.01) with 67.91% highest reduction in rat paw volume. Moreover, ellagic acid and methyl-(S)-flavogallonate showed significant binding affinity with iNOS (-8.5 and -8.7 Kcal/moL, respectively) and NF-κB (-7.3 and -7.3 Kcal/moL, respectively). CONCLUSION Mentionable basis was found on behalf of the anti-inflammatory and antioxidant potentials of ETM which might be correlated with its NF-ĸB inhibiting properties.
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Affiliation(s)
- Md Afjalus Siraj
- Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, 96720, HI, USA
| | - Md Sariful Islam Howlader
- Department of Pharmaceutical Sciences, Jerry H. Hodge School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106, USA; Department of Chemistry, Tennessee Technological University, Cookeville, TN, 38501, USA
| | - Md Arman Islam
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, 9208, Bangladesh
| | - Tanzira Irin
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, 9208, Bangladesh; Department of Pharmacy, ASA University Bangladesh, Dhaka, 1207, Bangladesh
| | - Jesus Simal-Gandara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004, Ourense, Spain.
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Raisi A, Dezfoulian O, Davoodi F, Taheri S, Ghahremani SA. Salvia miltiorrhiza hydroalcoholic extract inhibits postoperative peritoneal adhesions in rats. BMC Complement Med Ther 2021; 21:126. [PMID: 33879143 PMCID: PMC8056503 DOI: 10.1186/s12906-021-03300-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 04/08/2021] [Indexed: 01/22/2023] Open
Abstract
Background One of the most prevalent postoperative complications is believed to be intra-abdominal peritoneal adhesions, which is followed by several complications. Several adhesion prevention products have been examined, yet none of them were found to be completely effective. The current research is conducted to evaluate the beneficial effects of Salvia miltiorrhiza hydroalcoholic extract in inhibiting postoperative peritoneal adhesions in rats. Methods Forty rats were randomly classified into five equal groups (n = 8): 1) the normal group did not undergo surgical operations, 2) the control group in which the adhesion was induced, and which did not receive any treatment, 3) distilled water group that received distilled water, and 4,5) treatment groups treated with 1 and 5% of Salvia miltiorrhiza hydroalcoholic extract. The rats were euthanized 14 days following the surgery and the macroscopic score, the microscopic score of granulomatous inflammation and granulation tissue formation, IHC markers (vimentin, CD31, IL-1β, COX-2, and iNOS), and oxidative stress biomarkers (MDA, GPx, CAT, and TAC) were assessed in the experimental groups of the study. Results The difference between the control group and other groups for the adhesions macroscopic score, microscopic score, IHC markers, and oxidative stress biomarkers was significant (p < 0.05). Distilled water had no protective effect on the formation of peritoneal adhesions. Salvia miltiorrhiza treatment in two different doses significantly reduced macroscopic and microscopic scores, MDA concentration, Vimentin, IL-1β, COX-2, and iNOS compared to the control group (p < 0.05). The levels of GPx, CAT, and TAC in the treatment groups increased significantly compared with the control group (p < 0.05). Our findings revealed that a higher dose of Salvia miltiorrhiza was more effective in reducing peritoneal adhesions, proinflammatory and mesenchymal cell markers, and oxidative stress. Conclusions Salvia miltiorrhiza extract, owing to its strong antioxidant and anti-inflammatory properties, could effectively reduce peritoneal adhesions. Therefore, Salvia miltiorrhiza is recommended to be used as an effective anti-peritoneal post-operative adhesive agent.
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Affiliation(s)
- Abbas Raisi
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran.
| | - Omid Dezfoulian
- Department of Pathobiology, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran.
| | - Farshid Davoodi
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran
| | - Shayan Taheri
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran
| | - Soroush Afshar Ghahremani
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran
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Boudreau A, Burke S, Collier J, Richard AJ, Ribnicky DM, Stephens JM. Mechanisms of Artemisia scoparia's Anti-Inflammatory Activity in Cultured Adipocytes, Macrophages, and Pancreatic β-Cells. Obesity (Silver Spring) 2020; 28:1726-1735. [PMID: 32741148 PMCID: PMC7483878 DOI: 10.1002/oby.22912] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 04/22/2020] [Accepted: 05/11/2020] [Indexed: 12/19/2022]
Abstract
OBJECTIVE An ethanolic extract of Artemisia scoparia (SCO) improves adipose tissue function and reduces negative metabolic consequences of high-fat feeding. A. scoparia has a long history of medicinal use across Asia and has anti-inflammatory effects in various cell types and disease models. The objective of the current study was to investigate SCO's effects on inflammation in cells relevant to metabolic health. METHODS Inflammatory responses were assayed in cultured adipocytes, macrophages, and insulinoma cells by quantitative polymerase chain reaction, immunoblotting, and NF-κB reporter assays. RESULTS In tumor necrosis factor α-treated adipocytes, SCO mitigated ERK and NF-κB signaling as well as transcriptional responses but had no effect on fatty acid-binding protein 4 secretion. SCO also reduced levels of deleted in breast cancer 1 protein in adipocytes and inhibited inflammatory gene expression in stimulated macrophages. Finally, in pancreatic β-cells, SCO decreased NF-κB-responsive promoter activity induced by IL-1β treatment. CONCLUSIONS SCO's ability to promote adipocyte development and function is thought to mediate its insulin-sensitizing actions in vivo. Our findings that SCO inhibits inflammatory responses through at least two distinct signaling pathways (ERK and NF-κB) in three cell types known to contribute to metabolic disease reveal that SCO may act more broadly than previously thought to improve metabolic health.
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Affiliation(s)
- Anik Boudreau
- Pennington Biomedical Research Center, Baton Rouge, LA 70808
| | - Susan Burke
- Pennington Biomedical Research Center, Baton Rouge, LA 70808
| | - Jason Collier
- Pennington Biomedical Research Center, Baton Rouge, LA 70808
| | | | - David M. Ribnicky
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ
| | - Jacqueline M. Stephens
- Pennington Biomedical Research Center, Baton Rouge, LA 70808
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803
- To whom correspondence should be addressed: Jacqueline Stephens, Louisiana State University, Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, Phone (225) 763-2648, FAX (225) 578-2597,
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LncRNA MALAT1 induces the dysfunction of β cells via reducing the histone acetylation of the PDX-1 promoter in type 1 diabetes. Exp Mol Pathol 2020; 114:104432. [DOI: 10.1016/j.yexmp.2020.104432] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 02/27/2020] [Accepted: 03/28/2020] [Indexed: 12/14/2022]
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15
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Neuroprotective Effect of Optimized Yinxieling Formula in 6-OHDA-Induced Chronic Model of Parkinson's Disease through the Inflammation Pathway. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:2529641. [PMID: 31929812 PMCID: PMC6942822 DOI: 10.1155/2019/2529641] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/24/2019] [Accepted: 11/21/2019] [Indexed: 12/14/2022]
Abstract
Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra (SN)-striatum circuit, which is associated with glial activation and consequent chronic neuroinflammation. Optimized Yinxieling Formula (OYF) is a Chinese medicine that exerts therapeutical effect and antiinflammation property on psoriasis. Our previous study has proven that pretreatment with OYF could regulate glia-mediated inflammation in an acute mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Given that PD is a chronic degeneration disorder, this study applied another PD animal model induced by striatal injection of 6-hydroxydopamine (6-OHDA) to mimic the progressive damage of the SN-striatum dopamine system in rats. The OYF was administrated in the manner of pretreatment plus treatment. The effects of the OYF on motor behaviors were assessed with the apomorphine-induced rotation test and adjusting steps test. To confirm the effect of OYF on dopaminergic neurons and glia activation in this model, we analyzed the expression of tyrosine hydroxylase (TH) and glia markers, ionized calcium-binding adapter molecule 1 (Iba-1), and glial fibrillary acidic protein (GFAP) in the SN region of the rat PD model. Inflammation-associated factors, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were further evaluated in this model and in interferon-γ- (INF-γ-) induced murine macrophages RAW264.7 cells. The results from the in vivo study showed that OYF reversed the motor behavioral dysfunction in 6-OHDA-induced PD rats, upregulated the TH expression, decreased the immunoreactivity of Iba-1 and GFAP, and downregulated the mRNA levels of TNF-α and COX-2. The OYF also trended to decrease the mRNA levels of IL-1β and iNOS in vivo. The results from the in vitro study showed that OYF significantly decreased the mRNA levels of TNF-α, IL-1β, IL-6, iNOS, and COX-2. Therefore, this study suggests that OYF exerts antiinflammatory effects, which might be related to the protection of dopaminergic neurons in 6-OHDA-induced chronic neurotoxicity.
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Porcine Alveolar Macrophages' Nitric Oxide Synthase-Mediated Generation of Nitric Oxide Exerts Important Defensive Effects against Glaesserella parasuis Infection. Pathogens 2019; 8:pathogens8040234. [PMID: 31766159 PMCID: PMC6963498 DOI: 10.3390/pathogens8040234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/08/2019] [Accepted: 11/11/2019] [Indexed: 11/16/2022] Open
Abstract
Glaesserella parasuis is a habitual bacterium of pigs' upper respiratory tracts. Its infection initiates with the invasion and colonization of the lower respiratory tracts of pigs, and develops as the bacteria survive host pulmonary defenses and clearance by alveolar macrophages. Alveolar macrophage-derived nitric oxide (NO) is recognized as an important mediator that exerts antimicrobial activity as well as immunomodulatory effects. In this study, we investigated the effects and the signaling pathway of NO generation in porcine alveolar macrophages 3D4/21 during G. parasuis infection. We demonstrated a time and dose-dependent generation of NO in 3D4/21 cells by G. parasuis, and showed that NO production required bacterial viability and nitric oxide synthase 2 upregulation, which was largely contributed by G. parasuis-induced nuclear factor-κB signaling's activation. Moreover, the porcine alveolar macrophage-derived NO exhibited prominent bacteriostatic effects against G. parasuis and positive host immunomodulation effects by inducing the production of cytokines and chemokines during infection. G. parasuis in turn, selectively upregulated several nitrate reductase genes to better survive this NO stress, revealing a battle of wits during the bacteria-host interactions. To our knowledge, this is the first direct demonstration of NO production and its anti-infection effects in alveolar macrophages with G. parasuis infection.
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Yelins’ka AM, Akimov OY, Kostenko VO. Role of AP-1 transcriptional factor in development of oxidative and nitrosative stress in periodontal tissues during systemic inflammatory response. UKRAINIAN BIOCHEMICAL JOURNAL 2019. [DOI: 10.15407/ubj91.01.080] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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18
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Burke SJ, Batdorf HM, Burk DH, Martin TM, Mendoza T, Stadler K, Alami W, Karlstad MD, Robson MJ, Blakely RD, Mynatt RL, Collier JJ. Pancreatic deletion of the interleukin-1 receptor disrupts whole body glucose homeostasis and promotes islet β-cell de-differentiation. Mol Metab 2018; 14:95-107. [PMID: 29914854 PMCID: PMC6034063 DOI: 10.1016/j.molmet.2018.06.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 05/30/2018] [Accepted: 06/02/2018] [Indexed: 02/06/2023] Open
Abstract
Objective Pancreatic tissue, and islets in particular, are enriched in expression of the interleukin-1 receptor type I (IL-1R). Because of this enrichment, islet β-cells are exquisitely sensitive to the IL-1R ligands IL-1α and IL-1β, suggesting that signaling through this pathway regulates health and function of islet β-cells. Methods Herein, we report a targeted deletion of IL-1R in pancreatic tissue (IL-1RPdx1−/−) in C57BL/6J mice and in db/db mice on the C57 genetic background. Islet morphology, β-cell transcription factor abundance, and expression of the de-differentiation marker Aldh1a3 were analyzed by immunofluorescent staining. Glucose and insulin tolerance tests were used to examine metabolic status of these genetic manipulations. Glucose-stimulated insulin secretion was evaluated in vivo and in isolated islets ex vivo by perifusion. Results Pancreatic deletion of IL-1R leads to impaired glucose tolerance, a phenotype that is exacerbated by age. Crossing the IL-1RPdx1−/− with db/db mice worsened glucose tolerance without altering body weight. There were no detectable alterations in insulin tolerance between IL-1RPdx1−/− mice and littermate controls. However, glucose-stimulated insulin secretion was reduced in islets isolated from IL-1RPdx1−/− relative to control islets. Insulin output in vivo after a glucose challenge was also markedly reduced in IL-1RPdx1−/− mice when compared with littermate controls. Pancreatic islets from IL-1RPdx1−/− mice displayed elevations in Aldh1a3, a marker of de-differentiation, and reduction in nuclear abundance of the β-cell transcription factor MafA. Nkx6.1 abundance was unaltered. Conclusions There is an important physiological role for pancreatic IL-1R to promote glucose homeostasis by suppressing expression of Aldh1a3, sustaining MafA abundance, and supporting glucose-stimulated insulin secretion in vivo. Pancreatic deletion of IL-1R impairs glucose tolerance in young and old male mice. Pancreatic deletion of IL-1R worsens glucose tolerance in obese db/db mice. Deletion of IL-1R triggers expression of the de-differentiation marker Aldh1a3. IL-1 signaling in pancreatic tissue influences islet health and function.
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Affiliation(s)
- Susan J Burke
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Heidi M Batdorf
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - David H Burk
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Thomas M Martin
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Tamra Mendoza
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | | | - Wateen Alami
- Department of Surgery, University of Tennessee Health Science Center, Knoxville, TN, 37920, USA
| | - Michael D Karlstad
- Department of Surgery, University of Tennessee Health Science Center, Knoxville, TN, 37920, USA
| | - Matthew J Robson
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Randy D Blakely
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter FL, 33458, USA
| | - Randall L Mynatt
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - J Jason Collier
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA.
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Quintero-García M, Delgado-González E, Sánchez-Tusie A, Vázquez M, Aceves C, Anguiano B. Iodine prevents the increase of testosterone-induced oxidative stress in a model of rat prostatic hyperplasia. Free Radic Biol Med 2018; 115:298-308. [PMID: 29248723 DOI: 10.1016/j.freeradbiomed.2017.12.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 12/11/2017] [Accepted: 12/12/2017] [Indexed: 12/11/2022]
Abstract
Oxidative stress and inflammation are involved in the development and/or progression of benign prostatic hyperplasia (BPH). Molecular iodine (I2) induces antiproliferative and apoptotic effects in prostate cancer cells, but it is unknown if I2 regulates oxidative stress in the normal and/or tumoral prostate. The purpose of this study was to analyze the effects of I2 and celecoxib (Cxb) on oxidative stress and inflammation in a model of prostatic hyperplasia. Cxb was used as positive control of cyclooxygenase-2 (COX-2) inhibition. Prostatic hyperplasia was induced in male Wistar rats (170g) with testosterone (5mg/kg/week, for three weeks). One week before hyperplasia induction, I2 (25mg/day/rat) or Cxb (1.25mg/day/rat) was supplied for four weeks in the drinking water. Prostatic hyperplasia was evaluated by histological analysis, DNA content, and/or proliferating cell nuclear antigen (PCNA) expression. Lipoperoxidation (malondialdehyde) and nitrite (NO2-) levels were analyzed by colorimetric methods, while nitric oxide synthase (NOS), COX, and myeloperoxidase (MPO) enzymes were analyzed using RT-PCR, immunoblotting, and/or enzymatic assays. Levels of 15-F2t-isoprostanes, prostaglandins (PGE2), leukotrienes (LTB4), and tumor necrosis factor alpha (TNFα) were measured by ELISA. Control testosterone-treated animals exhibited hyperplasia in the dorsolateral prostate, as well as increments in almost all oxidative parameters except for COX-1, TNFα, or MPO. I2 and Cxb prevented epithelial hyperplasia (DNA content) and oxidative stress induction generated by testosterone in almost the same intensity, and the minimum I2 dose required was 2.5mg/rat. The antioxidant capacity of I2 was also analyzed in a cell-free system, showing that this element inhibited the conversion of nitrate (NO3-) to NO2-. I2 did not modify the prostatic oxidative state in testosterone untreated rats. In summary, our data showed that antiproliferative and antioxidant effects of I2 involve the inhibition of NOS and the COX-2 pathway. Further studies are necessary to analyze the therapeutic and/or adjuvant effects of I2 with first-line medications used to treat BPH.
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Affiliation(s)
- Michelle Quintero-García
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico
| | - Evangelina Delgado-González
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico
| | - Ana Sánchez-Tusie
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico
| | - Mario Vázquez
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico
| | - Carmen Aceves
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico
| | - Brenda Anguiano
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, 76230 Querétaro, Mexico.
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Collier JJ, Sparer TE, Karlstad MD, Burke SJ. Pancreatic islet inflammation: an emerging role for chemokines. J Mol Endocrinol 2017; 59:R33-R46. [PMID: 28420714 PMCID: PMC5505180 DOI: 10.1530/jme-17-0042] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 04/18/2017] [Indexed: 12/13/2022]
Abstract
Both type 1 and type 2 diabetes exhibit features of inflammation associated with alterations in pancreatic islet function and mass. These immunological disruptions, if unresolved, contribute to the overall pathogenesis of disease onset. This review presents the emerging role of pancreatic islet chemokine production as a critical factor regulating immune cell entry into pancreatic tissue as well as an important facilitator of changes in tissue resident leukocyte activity. Signaling through two specific chemokine receptors (i.e., CXCR2 and CXCR3) is presented to illustrate key points regarding ligand-mediated regulation of innate and adaptive immune cell responses. The prospective roles of chemokine ligands and their corresponding chemokine receptors to influence the onset and progression of autoimmune- and obesity-associated forms of diabetes are discussed.
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MESH Headings
- Adaptive Immunity
- Animals
- Chemokines/genetics
- Chemokines/immunology
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/immunology
- Diabetes Mellitus, Type 2/pathology
- Disease Models, Animal
- Gene Expression Regulation
- Humans
- Immunity, Innate
- Inflammation
- Islets of Langerhans/immunology
- Islets of Langerhans/pathology
- Leukocytes/immunology
- Leukocytes/pathology
- Obesity/genetics
- Obesity/immunology
- Obesity/pathology
- Receptors, CXCR3/genetics
- Receptors, CXCR3/immunology
- Receptors, Interleukin-8B/genetics
- Receptors, Interleukin-8B/immunology
- Signal Transduction
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Affiliation(s)
- J Jason Collier
- Laboratory of Islet Biology and InflammationPennington Biomedical Research Center, Baton Rouge, Louisiana, USA
- Department of SurgeryGraduate School of Medicine, University of Tennessee Health Science Center, Knoxville, Tennessee, USA
| | - Tim E Sparer
- Department of MicrobiologyUniversity of Tennessee, Knoxville, Knoxville, Tennessee, USA
| | - Michael D Karlstad
- Department of SurgeryGraduate School of Medicine, University of Tennessee Health Science Center, Knoxville, Tennessee, USA
| | - Susan J Burke
- Laboratory of ImmunogeneticsPennington Biomedical Research Center, Baton Rouge, Louisiana, USA
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Burke SJ, Karlstad MD, Eder AE, Regal KM, Lu D, Burk DH, Collier JJ. Pancreatic β-Cell production of CXCR3 ligands precedes diabetes onset. Biofactors 2016; 42:703-715. [PMID: 27325565 PMCID: PMC5177512 DOI: 10.1002/biof.1304] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 05/18/2016] [Indexed: 12/18/2022]
Abstract
Type 1 diabetes mellitus (T1DM) results from immune cell-mediated reductions in function and mass of the insulin-producing β-cells within the pancreatic islets. While the initial trigger(s) that initiates the autoimmune process is unknown, there is a leukocytic infiltration that precedes islet β-cell death and dysfunction. Herein, we demonstrate that genes encoding the chemokines CXCL9, 10, and 11 are primary response genes in pancreatic β-cells and are also elevated as part of the inflammatory response in mouse, rat, and human islets. We further established that STAT1 participates in the transcriptional control of these genes in response to the pro-inflammatory cytokines IL-1β and IFN-γ. STAT1 is phosphorylated within five minutes after β-cell exposure to IFN-γ, with subsequent occupancy at proximal and distal response elements within the Cxcl9 and Cxcl11 gene promoters. This increase in STAT1 binding is coupled to the rapid appearance of chemokine transcript. Moreover, circulating levels of chemokines that activate CXCR3 are elevated in non-obese diabetic (NOD) mice, consistent with clinical findings in human diabetes. We also report herein that mice with genetic deletion of CXCR3 (receptor for ligands CXCL9, 10, and 11) exhibit a delay in diabetes development after being injected with multiple low doses of streptozotocin. Therefore, we conclude that production of CXCL9, 10, and 11 from islet β-cells controls leukocyte migration and activity into pancreatic tissue, which ultimately influences islet β-cell mass and function. © 2016 BioFactors, 42(6):703-715, 2016.
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Affiliation(s)
- Susan J. Burke
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Michael D. Karlstad
- Department of Surgery, Graduate School of Medicine, University of Tennessee Health Science Center, Knoxville, TN
| | - Adrianna E. Eder
- Department of Surgery, Graduate School of Medicine, University of Tennessee Health Science Center, Knoxville, TN
| | - Kellie M. Regal
- Department of Surgery, Graduate School of Medicine, University of Tennessee Health Science Center, Knoxville, TN
| | - Danhong Lu
- Sarah W. Stedman Nutrition and Metabolism Center, Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - David H. Burk
- Cell Biology and Bioimaging Core Facility, Pennington Biomedical Research Center, Baton Rouge, LA
| | - J. Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA
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Sandoval J, Pereda J, Pérez S, Finamor I, Vallet-Sánchez A, Rodríguez JL, Franco L, Sastre J, López-Rodas G. Epigenetic Regulation of Early- and Late-Response Genes in Acute Pancreatitis. THE JOURNAL OF IMMUNOLOGY 2016; 197:4137-4150. [PMID: 27798150 DOI: 10.4049/jimmunol.1502378] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 09/16/2016] [Indexed: 12/12/2022]
Abstract
Chromatin remodeling seems to regulate the patterns of proinflammatory genes. Our aim was to provide new insights into the epigenetic mechanisms that control transcriptional activation of early- and late-response genes in initiation and development of severe acute pancreatitis as a model of acute inflammation. Chromatin changes were studied by chromatin immunoprecipitation analysis, nucleosome positioning, and determination of histone modifications in promoters of proinflammatory genes in vivo in the course of taurocholate-induced necrotizing pancreatitis in rats and in vitro in rat pancreatic AR42J acinar cells stimulated with taurocholate or TNF-α. Here we show that the upregulation of early and late inflammatory genes rely on histone acetylation associated with recruitment of histone acetyltransferase CBP. Chromatin remodeling of early genes during the inflammatory response in vivo is characterized by a rapid and transient increase in H3K14ac, H3K27ac, and H4K5ac as well as by recruitment of chromatin-remodeling complex containing BRG-1. Chromatin remodeling in late genes is characterized by a late and marked increase in histone methylation, particularly in H3K4. JNK and p38 MAPK drive the recruitment of transcription factors and the subsequent upregulation of early and late inflammatory genes, which is associated with nuclear translocation of the early gene Egr-1 In conclusion, specific and strictly ordered epigenetic markers such as histone acetylation and methylation, as well as recruitment of BRG-1-containing remodeling complex are associated with the upregulation of both early and late proinflammatory genes in acute pancreatitis. Our findings highlight the importance of epigenetic regulatory mechanisms in the control of the inflammatory cascade.
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Affiliation(s)
- Juan Sandoval
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, 46100 Valencia, Spain
| | - Javier Pereda
- Department of Physiology, Faculty of Pharmacy, University of Valencia, 46100 Valencia, Spain; and
| | - Salvador Pérez
- Department of Physiology, Faculty of Pharmacy, University of Valencia, 46100 Valencia, Spain; and
| | - Isabela Finamor
- Department of Physiology, Faculty of Pharmacy, University of Valencia, 46100 Valencia, Spain; and
| | - Azahara Vallet-Sánchez
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, 46100 Valencia, Spain.,Institute of Health Research INCLIVA (Foundation for Research of the Clinic Hospital of the "Comunidad Valenciana"), 46010 Valencia, Spain
| | - José Luis Rodríguez
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, 46100 Valencia, Spain
| | - Luis Franco
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, 46100 Valencia, Spain.,Institute of Health Research INCLIVA (Foundation for Research of the Clinic Hospital of the "Comunidad Valenciana"), 46010 Valencia, Spain
| | - Juan Sastre
- Department of Physiology, Faculty of Pharmacy, University of Valencia, 46100 Valencia, Spain; and
| | - Gerardo López-Rodas
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Valencia, 46100 Valencia, Spain.,Institute of Health Research INCLIVA (Foundation for Research of the Clinic Hospital of the "Comunidad Valenciana"), 46010 Valencia, Spain
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23
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Dey P, Panga V, Raghunathan S. A Cytokine Signalling Network for the Regulation of Inducible Nitric Oxide Synthase Expression in Rheumatoid Arthritis. PLoS One 2016; 11:e0161306. [PMID: 27626941 PMCID: PMC5023176 DOI: 10.1371/journal.pone.0161306] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 08/03/2016] [Indexed: 12/22/2022] Open
Abstract
In rheumatoid arthritis (RA), nitric oxide (NO) is implicated in inflammation, angiogenesis and tissue destruction. The enzyme inducible nitric oxide synthase (iNOS) is responsible for the localised over-production of NO in the synovial joints affected by RA. The pro- and anti-inflammatory cytokines stimulate the synovial macrophages and the fibroblast-like synoviocytes to express iNOS. Therefore, the cytokine signalling network underlying the regulation of iNOS is essential to understand the pathophysiology of the disease. By using information from the literature, we have constructed, for the first time, the cytokine signalling network involved in the regulation of iNOS expression. Using the differential expression patterns obtained by re-analysing the microarray data on the RA synovium and the synovial macrophages available in the Gene Expression Omnibus (GEO) database, we aimed to establish the role played by the network genes towards iNOS regulation in the RA synovium. Our analysis reveals that the network genes belonging to interferon (IFN) and interleukin-10 (IL-10) pathways are always up-regulated in the RA synovium whereas the genes which are part of the anti-inflammatory transforming growth factor-beta (TGF-β) signalling pathway are mostly down-regulated. We observed a consistent up-regulation of the transcription factor signal transducers and activators of transcription 1 (STAT1) in the RA synovium and the macrophages. Interestingly, we found a consistent up-regulation of the iNOS interacting protein ras-related C3 botulinum toxin substrate 2 (RAC2) in the RA synovium as well as the macrophages. Importantly, we have constructed a model to explain the impact of IFN and IL-10 pathways on Rac2-iNOS interaction leading to over-production of NO and thereby causing chronic inflammation in the RA synovium. The interplay between STAT1 and RAC2 in the regulation of NO could have implications for the identification of therapeutic targets for RA.
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Affiliation(s)
- Poulami Dey
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Biotech Park, Electronics City Phase I, Bengaluru 560 100, Karnataka, India
- Manipal University, Manipal, 576104, Karnataka, India
| | - Venugopal Panga
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Biotech Park, Electronics City Phase I, Bengaluru 560 100, Karnataka, India
- Manipal University, Manipal, 576104, Karnataka, India
| | - Srivatsan Raghunathan
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Biotech Park, Electronics City Phase I, Bengaluru 560 100, Karnataka, India
- * E-mail:
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24
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Type I interferons exert anti-tumor effect via reversing immunosuppression mediated by mesenchymal stromal cells. Oncogene 2016; 35:5953-5962. [PMID: 27109100 PMCID: PMC5079855 DOI: 10.1038/onc.2016.128] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 03/06/2016] [Accepted: 03/15/2016] [Indexed: 12/13/2022]
Abstract
Mesenchymal stromal cells (MSCs) are strongly immunosuppressive via producing nitric oxide (NO) and known to migrate into tumor sites to promote tumor growth, but the underlying mechanisms remain largely elusive. Here, we found that interferon alpha (IFNα)-secreting MSCs showed more dramatic inhibition effect on tumor progression than that of IFNα alone. Interestingly, IFNα-primed MSCs could also effectively suppress tumor growth. Mechanistically, we demonstrated that both IFNα and IFNβ (type I IFNs) reversed the immunosuppressive effect of MSCs on splenocyte proliferation. This effect of type I IFNs was exerted through inhibiting inducible NO synthase (iNOS) expression in IFNγ and TNFα-stimulated MSCs. Notably, only NO production was inhibited by IFNα production of other cytokines or chemokines tested was not suppressed. Furthermore, IFNα promoted the switch from signal transducer and activator of transcription 1 (Stat1) homodimers to Stat1-Stat2 heterodimers. Studies using the luciferase reporter system and chromatin immunoprecipitation assay revealed that IFNα suppressed iNOS transcription through inhibiting the binding of Stat1 to iNOS promoter. Therefore, the synergistic anti-tumor effects of type I IFNs and MSCs were achieved by inhibiting NO production. This study provides essential information for understanding the mechanisms of MSC-mediated immunosuppression and for the development of better clinical strategies using IFNs and MSCs for cancer immunotherapy.
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25
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Gao Q, Liu Y, Wu Y, Zhao Q, Wang L, Gao S, Wen W, Zhang W, Guo N, Zhou J, Yuan Z. IL-17 intensifies IFN-γ-induced NOS2 upregulation in RAW 264.7 cells by further activating STAT1 and NF-κB. Int J Mol Med 2015; 37:347-58. [PMID: 26677135 PMCID: PMC4716793 DOI: 10.3892/ijmm.2015.2433] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 12/08/2015] [Indexed: 12/20/2022] Open
Abstract
Interleukin-17 (IL-17) is a signature cytokine of Th17 cells. Previous research has indicated that IL-17 plays a proinflammatory role by exacerbating interferon-γ (IFN-γ)-induced inflammation. However, prior to this study, it was not known whether inducible nitric oxide synthase (iNOS or NOS2), a signature molecule of inflammation, could be intensified by IL-17 when combined with IFN-γ. Thus, we explored the roles and underlying mechanisms of IL-17 and IFN-γ in the regulation of NOS2 expression in RAW 264.7 cells using qPCR, western blot analysis, colorimetric analysis, ChIP assay and statistical analysis. Although IL-17 alone did not induce NOS2 expression or nitric oxide (NO) production, as shown by western blot analysis and colorimetric analysis, it intensified IFN-γ-induced NOS2 upregulation and NO production in RAW 264.7 cells. The alteration of relevant transcription factors demonstrated that a combination of IFN-γ and IL-17 enhanced Tyr701-phosphorylated signal transducer and activator of transcription 1 [p-STAT1(Y701)] and nuclear factor-κB (NF-κB) activation, nuclear translocations and their binding to the NOS2 promoter, compared with IFN-γ alone, as illustrated by the results of the western blot analysis and ChIP assay. Also, using the corresponding inhibitors of STAT1 and NF-κB, we noted downregulation of the expression of NOS2 induced by IFN-γ alone or in combination with IL-17, respectively. In addition, IFN-γ increased phosphorylated (p-)p38 mitogen-activated protein kinase (MAPK), and accelerated the activation of the NF-κB pathway and the expression of NOS2, but phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) was reduced by treatment with IFN-γ and IL-17. IL-17 intensified the activation of the NF-κB pathway and NOS2 upregulation induced by IFN-γ by increasing the phosphorylation of p38 MAPK and limiting the phosphorylation of ERK1/2. Taken together, these results suggest that IL-17 intensified IFN-γ-induced NOS2 upregulation and NO production by increasing the transcription activity of p-STAT1(Y701) and NF-κB in RAW 264.7 cells. Further activation of the NF-κB pathway induced by IL-17 relied on enhanced phosphorylation of p38 MAPK and decreased phosphorylation of ERK1/2. The mechanism suggested in this study provides novel information which may be used for anti-inflammatory therapy with IL-17.
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Affiliation(s)
- Qiyue Gao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Yang Liu
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Yan Wu
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Qiang Zhao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Lijun Wang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Shanshan Gao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Wen Wen
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Weiping Zhang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Ning Guo
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Juan Zhou
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Zuyi Yuan
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
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26
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Burke SJ, Stadler K, Lu D, Gleason E, Han A, Donohoe DR, Rogers RC, Hermann GE, Karlstad MD, Collier JJ. IL-1β reciprocally regulates chemokine and insulin secretion in pancreatic β-cells via NF-κB. Am J Physiol Endocrinol Metab 2015; 309:E715-26. [PMID: 26306596 PMCID: PMC4609876 DOI: 10.1152/ajpendo.00153.2015] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 08/17/2015] [Indexed: 01/04/2023]
Abstract
Proinflammatory cytokines impact islet β-cell mass and function by altering the transcriptional activity within pancreatic β-cells, producing increases in intracellular nitric oxide abundance and the synthesis and secretion of immunomodulatory proteins such as chemokines. Herein, we report that IL-1β, a major mediator of inflammatory responses associated with diabetes development, coordinately and reciprocally regulates chemokine and insulin secretion. We discovered that NF-κB controls the increase in chemokine transcription and secretion as well as the decrease in both insulin secretion and proliferation in response to IL-1β. Nitric oxide production, which is markedly elevated in pancreatic β-cells exposed to IL-1β, is a negative regulator of both glucose-stimulated insulin secretion and glucose-induced increases in intracellular calcium levels. By contrast, the IL-1β-mediated production of the chemokines CCL2 and CCL20 was not influenced by either nitric oxide levels or glucose concentration. Instead, the synthesis and secretion of CCL2 and CCL20 in response to IL-1β were dependent on NF-κB transcriptional activity. We conclude that IL-1β-induced transcriptional reprogramming via NF-κB reciprocally regulates chemokine and insulin secretion while also negatively regulating β-cell proliferation. These findings are consistent with NF-κB as a major regulatory node controlling inflammation-associated alterations in islet β-cell function and mass.
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Affiliation(s)
- Susan J Burke
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, Louisiana
| | - Krisztian Stadler
- Laboratory of Oxidative Stress and Disease, Pennington Biomedical Research Center, Baton Rouge, Louisiana
| | - Danhong Lu
- Duke Molecular Physiology Institute, Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina
| | - Evanna Gleason
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Anna Han
- Department of Nutrition, University of Tennessee, Knoxville, Knoxville, Tennessee
| | - Dallas R Donohoe
- Department of Nutrition, University of Tennessee, Knoxville, Knoxville, Tennessee
| | - Richard C Rogers
- Laboratory of Autonomic Neuroscience, Pennington Biomedical Research Center, Baton Rouge, Louisiana; and
| | - Gerlinda E Hermann
- Laboratory of Autonomic Neuroscience, Pennington Biomedical Research Center, Baton Rouge, Louisiana; and
| | - Michael D Karlstad
- Department of Surgery, Graduate School of Medicine, University of Tennessee Medical Center, Knoxville, Tennessee
| | - J Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, Louisiana;
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Transcriptional regulation of chemokine genes: a link to pancreatic islet inflammation? Biomolecules 2015; 5:1020-34. [PMID: 26018641 PMCID: PMC4496708 DOI: 10.3390/biom5021020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 05/12/2015] [Indexed: 12/18/2022] Open
Abstract
Enhanced expression of chemotactic cytokines (aka chemokines) within pancreatic islets likely contributes to islet inflammation by regulating the recruitment and activation of various leukocyte populations, including macrophages, neutrophils, and T-lymphocytes. Because of the powerful actions of these chemokines, precise transcriptional control is required. In this review, we highlight what is known about the signals and mechanisms that govern the transcription of genes encoding specific chemokine proteins in pancreatic islet β-cells, which include contributions from the NF-κB and STAT1 pathways. We further discuss increased chemokine expression in pancreatic islets during autoimmune-mediated and obesity-related development of diabetes.
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28
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CCL20 is elevated during obesity and differentially regulated by NF-κB subunits in pancreatic β-cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2015; 1849:637-52. [PMID: 25882704 DOI: 10.1016/j.bbagrm.2015.03.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 03/05/2015] [Accepted: 03/30/2015] [Indexed: 12/20/2022]
Abstract
Enhanced leukocytic infiltration into pancreatic islets contributes to inflammation-based diminutions in functional β-cell mass. Insulitis (aka islet inflammation), which can be present in both T1DM and T2DM, is one factor influencing pancreatic β-cell death and dysfunction. IL-1β, an inflammatory mediator in both T1DM and T2DM, acutely (within 1h) induced expression of the CCL20 gene in rat and human islets and clonal β-cell lines. Transcriptional induction of CCL20 required the p65 subunit of NF-κB to replace the p50 subunit at two functional κB sites within the CCL20 proximal gene promoter. The NF-κB p50 subunit prevents CCL20 gene expression during unstimulated conditions and overexpression of p50 reduces CCL20, but enhances cyclooxygenase-2 (COX-2), transcript accumulation after exposure to IL-1β. We also identified differential recruitment of specific co-activator molecules to the CCL20 gene promoter, when compared with the CCL2 and COX2 genes, revealing distinct transcriptional requirements for individual NF-κB responsive genes. Moreover, IL-1β, TNF-α and IFN-γ individually increased the expression of CCR6, the receptor for CCL20, on the surface of human neutrophils. We further found that the chemokine CCL20 is elevated in serum from both genetically obese db/db mice and in C57BL6/J mice fed a high-fat diet. Taken together, these results are consistent with a possible activation of the CCL20-CCR6 axis in diseases with inflammatory components. Thus, interfering with this signaling pathway, either at the level of NF-κB-mediated chemokine production, or downstream receptor activation, could be a potential therapeutic target to offset inflammation-associated tissue dysfunction in obesity and diabetes.
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29
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Dietary polyherbal supplementation decreases CD3+ cell infiltration into pancreatic islets and prevents hyperglycemia in nonobese diabetic mice. Nutr Res 2015; 35:328-36. [DOI: 10.1016/j.nutres.2014.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/17/2014] [Accepted: 12/19/2014] [Indexed: 01/26/2023]
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30
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Hoeksema MA, Scicluna BP, Boshuizen MCS, van der Velden S, Neele AE, Van den Bossche J, Matlung HL, van den Berg TK, Goossens P, de Winther MPJ. IFN-γ priming of macrophages represses a part of the inflammatory program and attenuates neutrophil recruitment. THE JOURNAL OF IMMUNOLOGY 2015; 194:3909-16. [PMID: 25750432 DOI: 10.4049/jimmunol.1402077] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 02/02/2015] [Indexed: 01/22/2023]
Abstract
Macrophages form a heterogeneous population of immune cells, which is critical for both the initiation and resolution of inflammation. They can be skewed to a proinflammatory subtype by the Th1 cytokine IFN-γ and further activated with TLR triggers, such as LPS. In this work, we investigated the effects of IFN-γ priming on LPS-induced gene expression in primary mouse macrophages. Surprisingly, we found that IFN-γ priming represses a subset of LPS-induced genes, particularly genes involved in cellular movement and leukocyte recruitment. We found STAT1-binding motifs enriched in the promoters of these repressed genes. Furthermore, in the absence of STAT1, affected genes are derepressed. We also observed epigenetic remodeling by IFN-γ priming on enhancer or promoter sites of repressed genes, which resulted in less NF-κB p65 recruitment to these sites without effects on global NF-κB activation. Finally, the epigenetic and transcriptional changes induced by IFN-γ priming reduce neutrophil recruitment in vitro and in vivo. Our data show that IFN-γ priming changes the inflammatory repertoire of macrophages, leading to a change in neutrophil recruitment to inflammatory sites.
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Affiliation(s)
- Marten A Hoeksema
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Brendon P Scicluna
- Center for Experimental Molecular Medicine, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands; Center for Infection and Immunity, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Marieke C S Boshuizen
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Saskia van der Velden
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Annette E Neele
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Jan Van den Bossche
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Hanke L Matlung
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands; and
| | - Timo K van den Berg
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands; and
| | - Pieter Goossens
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, UM2, 13288 Marseille, France
| | - Menno P J de Winther
- Experimental Vascular Biology Laboratory, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands;
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Translational implications of the β-cell epigenome in diabetes mellitus. Transl Res 2015; 165:91-101. [PMID: 24686035 PMCID: PMC4162854 DOI: 10.1016/j.trsl.2014.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 03/04/2014] [Accepted: 03/06/2014] [Indexed: 12/12/2022]
Abstract
Diabetes mellitus is a disorder of glucose homeostasis that affects more than 24 million Americans and 382 million individuals worldwide. Dysregulated insulin secretion from the pancreatic β cells plays a central role in the pathophysiology of all forms of diabetes mellitus. Therefore, an enhanced understanding of the pathways that contribute to β-cell failure is imperative. Epigenetics refers to heritable changes in DNA transcription that occur in the absence of changes to the linear DNA nucleotide sequence. Recent evidence suggests an expanding role of the β-cell epigenome in the regulation of metabolic health. The goal of this review is to discuss maladaptive changes in β-cell DNA methylation patterns and chromatin architecture, and their contribution to diabetes pathophysiology. Efforts to modulate the β-cell epigenome as a means to prevent, diagnose, and treat diabetes are also discussed.
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32
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Yao Y, Chen L, Xiao J, Wang C, Jiang W, Zhang R, Hao J. Chrysin protects against focal cerebral ischemia/reperfusion injury in mice through attenuation of oxidative stress and inflammation. Int J Mol Sci 2014; 15:20913-26. [PMID: 25402649 PMCID: PMC4264203 DOI: 10.3390/ijms151120913] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/19/2014] [Accepted: 11/03/2014] [Indexed: 12/29/2022] Open
Abstract
Inflammation and oxidative stress play an important part in the pathogenesis of focal cerebral ischemia/reperfusion (I/R) injury, resulting in neuronal death. The signaling pathways involved and the underlying mechanisms of these events are not fully understood. Chrysin, which is a naturally occurring flavonoid, exhibits various biological activities. In this study, we investigated the neuroprotective properties of chrysin in a mouse model of middle cerebral artery occlusion (MCAO). To this end, male C57/BL6 mice were pretreated with chrysin once a day for seven days and were then subjected to 1 h of middle cerebral artery occlusion followed by reperfusion for 24 h. Our data show that chrysin successfully decreased neurological deficit scores and infarct volumes, compared with the vehicle group. The increases in glial cell numbers and proinflammatory cytokine secretion usually caused by ischemia/reperfusion were significantly ameliorated by chrysin pretreatment. Moreover, chrysin also inhibited the MCAO-induced up-regulation of nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS), compared with the vehicle. These results suggest that chrysin could be a potential prophylactic agent for cerebral ischemia/reperfusion (I/R) injury mediated by its anti-inflammatory and anti-oxidative effects.
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Affiliation(s)
- Yang Yao
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Li Chen
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Jinting Xiao
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Chunyang Wang
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Wei Jiang
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Rongxin Zhang
- Laboratory of Immunology and Inflammation, Research Center of Basic Medical Science, Tianjin Medical University, Tianjin 300070, China.
| | - Junwei Hao
- Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052, China.
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33
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Dahllöf MS, Christensen DP, Harving M, Wagner BK, Mandrup-Poulsen T, Lundh M. HDAC inhibitor-mediated beta-cell protection against cytokine-induced toxicity is STAT1 Tyr701 phosphorylation independent. J Interferon Cytokine Res 2014; 35:63-70. [PMID: 25062500 DOI: 10.1089/jir.2014.0022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Histone deacetylase (HDAC) inhibition protects pancreatic beta-cells against apoptosis induced by the combination of the proinflammatory cytokines interleukin (IL)-1β and interferon (IFN)-γ. Decreased expression of cell damage-related genes is observed on the transcriptional level upon HDAC inhibition using either IL-1β or IFN-γ alone. Whereas HDAC inhibition has been shown to regulate NFκB-activity, related primarily to IL-1β signaling, it is unknown whether the inhibition of HDACs affect IFN-γ signaling in beta-cells. Further, in non-beta-cells, there is a dispute whether HDAC inhibition regulates IFN-γ signaling at the level of STAT1 Tyr701 phosphorylation. Using different small molecule HDAC inhibitors with varying class selectivity, INS-1E wild type and stable HDAC1-3 knockdown pancreatic INS-1 cell lines, we show that IFN-γ-induced Cxcl9 and iNos expression as well as Cxcl9 and GAS reporter activity were decreased by HDAC inhibition in a STAT1 Tyr701 phosphorylation-independent fashion. In fact, knockdown of HDAC1 increased IFN-γ-induced STAT1 phosphorylation.
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Affiliation(s)
- Mattias S Dahllöf
- 1 Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen, Denmark
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34
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Burke SJ, Lu D, Sparer TE, Karlstad MD, Collier JJ. Transcription of the gene encoding TNF-α is increased by IL-1β in rat and human islets and β-cell lines. Mol Immunol 2014; 62:54-62. [PMID: 24972324 DOI: 10.1016/j.molimm.2014.05.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 05/08/2014] [Accepted: 05/24/2014] [Indexed: 11/28/2022]
Abstract
Synthesis and secretion of immunomodulatory proteins, such as cytokines and chemokines, controls the inflammatory response within pancreatic islets. When this inflammation does not resolve, destruction of pancreatic islet β-cells leads to diabetes mellitus. Production of the soluble mediators of inflammation, such as TNF-α and IL-1β, from resident and invading immune cells, as well as directly from islet β-cells, is also associated with suboptimal islet transplantation outcomes. In this study, we found that IL-1β induces rapid increases in TNF-α mRNA in rat and human islets and the 832/13 clonal β-cell line. The surge in transcription of the TNF-α gene required the inhibitor of kappa B kinase beta (IκKβ), the p65 subunit of the NF-κB and a signal-specific recruitment of RNA polymerase II to the gene promoter. Of note was the increased intracellular production of TNF-α protein in a manner consistent with mRNA accumulation in response to IL-1β, but no detectable secretion of TNF-α into the media. Additionally, TNF-α specifically induces expression of CD11b, but not CD11c, on neutrophils, which could contribute to the inflammatory milieu and diabetes progression. We conclude that activation of the NF-κB pathway in pancreatic β-cells leads to rapid intracellular production of the pro-inflammatory TNF-α protein through a combination of specific histone covalent modifications and NF-κB signaling pathways.
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Affiliation(s)
- Susan J Burke
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States
| | - Danhong Lu
- Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, NC 27704, United States
| | - Tim E Sparer
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
| | - Michael D Karlstad
- Department of Surgery, Graduate School of Medicine, University of Tennessee Medical Center, Knoxville, TN 37920, United States
| | - J Jason Collier
- Laboratory of Islet Biology and Inflammation, Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States.
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Burke SJ, Lu D, Sparer TE, Masi T, Goff MR, Karlstad MD, Collier JJ. NF-κB and STAT1 control CXCL1 and CXCL2 gene transcription. Am J Physiol Endocrinol Metab 2014; 306:E131-49. [PMID: 24280128 PMCID: PMC3920007 DOI: 10.1152/ajpendo.00347.2013] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Diabetes mellitus results from immune cell invasion into pancreatic islets of Langerhans, eventually leading to selective destruction of the insulin-producing β-cells. How this process is initiated is not well understood. In this study, we investigated the regulation of the CXCL1 and CXCL2 genes, which encode proteins that promote migration of CXCR2(+) cells, such as neutrophils, toward secreting tissue. Herein, we found that IL-1β markedly enhanced the expression of the CXCL1 and CXCL2 genes in rat islets and β-cell lines, which resulted in increased secretion of each of these proteins. CXCL1 and CXCL2 also stimulated the expression of specific integrin proteins on the surface of human neutrophils. Mutation of a consensus NF-κB genomic sequence present in both gene promoters reduced the ability of IL-1β to promote transcription. In addition, IL-1β induced binding of the p65 and p50 subunits of NF-κB to these consensus κB regulatory elements as well as to additional κB sites located near the core promoter regions of each gene. Additionally, serine-phosphorylated STAT1 bound to the promoters of the CXCL1 and CXCL2 genes. We further found that IL-1β induced specific posttranslational modifications to histone H3 in a time frame congruent with transcription factor binding and transcript accumulation. We conclude that IL-1β-mediated regulation of the CXCL1 and CXCL2 genes in pancreatic β-cells requires stimulus-induced changes in histone chemical modifications, recruitment of the NF-κB and STAT1 transcription factors to genomic regulatory sequences within the proximal gene promoters, and increases in phosphorylated forms of RNA polymerase II.
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Affiliation(s)
- Susan J Burke
- Department of Nutrition, University of Tennessee, Knoxville, Tennessee
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