101
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Germic N, Frangez Z, Yousefi S, Simon HU. Regulation of the innate immune system by autophagy: monocytes, macrophages, dendritic cells and antigen presentation. Cell Death Differ 2019; 26:715-727. [PMID: 30737475 DOI: 10.1038/s41418-019-0297-6] [Citation(s) in RCA: 191] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 01/19/2019] [Accepted: 01/22/2019] [Indexed: 12/27/2022] Open
Abstract
Autophagy is well equipped functionally to isolate microbial pathogens in autophagosomes and to carry out their clearance by dismemberment in the course of catabolic processes in the lysosome. Clearly, this is a non-metabolic function of autophagy that impacts strongly on the immune system. While in a preceding article on neutrophils, eosinophils, mast cells, and natural killer cells our focus was on the role of autophagy in regulating innate immune cell differentiation, degranulation, phagocytosis and extracellular trap formation, here we discuss monocytes/macrophages and dendritic cells, specifically, the influence of autophagy on functional cellular responses, such as phagocytosis, antigen presentation, cytokine production, control of inflammasome activation, tolerance and the consequences for overall host defense.
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Affiliation(s)
- Nina Germic
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Ziva Frangez
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland. .,Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia.
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102
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Protective Features of Autophagy in Pulmonary Infection and Inflammatory Diseases. Cells 2019; 8:cells8020123. [PMID: 30717487 PMCID: PMC6406971 DOI: 10.3390/cells8020123] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a highly conserved catabolic process involving autolysosomal degradation of cellular components, including protein aggregates, damaged organelles (such as mitochondria, endoplasmic reticulum, and others), as well as various pathogens. Thus, the autophagy pathway represents a major adaptive response for the maintenance of cellular and tissue homeostasis in response to numerous cellular stressors. A growing body of evidence suggests that autophagy is closely associated with diverse human diseases. Specifically, acute lung injury (ALI) and inflammatory responses caused by bacterial infection or xenobiotic inhalation (e.g., chlorine and cigarette smoke) have been reported to involve a spectrum of alterations in autophagy phenotypes. The role of autophagy in pulmonary infection and inflammatory diseases could be protective or harmful dependent on the conditions. In this review, we describe recent advances regarding the protective features of autophagy in pulmonary diseases, with a focus on ALI, idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), tuberculosis, pulmonary arterial hypertension (PAH) and cystic fibrosis.
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103
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Regulation of Inflammasome by Autophagy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1209:109-123. [DOI: 10.1007/978-981-15-0606-2_7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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104
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Abstract
Sepsis was known to ancient Greeks since the time of great physician Hippocrates (460-377 BC) without exact information regarding its pathogenesis. With time and medical advances, it is now considered as a condition associated with organ dysfunction occurring in the presence of systemic infection as a result of dysregulation of the immune response. Still with this advancement, we are struggling for the development of target-based therapeutic approach for the management of sepsis. The advancement in understanding the immune system and its working has led to novel discoveries in the last 50 years, including different pattern recognition receptors. Inflammasomes are also part of these novel discoveries in the field of immunology which are <20 years old in terms of their first identification. They serve as important cytosolic pattern recognition receptors required for recognizing cytosolic pathogens, and their pathogen-associated molecular patterns play an important role in the pathogenesis of sepsis. The activation of both canonical and non-canonical inflammasome signaling pathways is involved in mounting a proinflammatory immune response via regulating the generation of IL-1β, IL-18, IL-33 cytokines and pyroptosis. In addition to pathogens and their pathogen-associated molecular patterns, death/damage-associated molecular patterns and other proinflammatory molecules involved in the pathogenesis of sepsis affect inflammasomes and vice versa. Thus, the present review is mainly focused on the inflammasomes, their role in the regulation of immune response associated with sepsis, and their targeting as a novel therapeutic approach.
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Affiliation(s)
- Vijay Kumar
- Children's Health Queensland Clinical Unit, School of Clinical Medicine, Faculty of Medicine, Mater Research, University of Queensland, Brisbane, Australia,
- School of Biomedical Sciences, Faculty of Medicine, University of Queensland, Brisbane, Australia,
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105
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Jiang C, Jiang L, Li Q, Liu X, Zhang T, Dong L, Liu T, Liu L, Hu G, Sun X, Jiang L. Acrolein induces NLRP3 inflammasome-mediated pyroptosis and suppresses migration via ROS-dependent autophagy in vascular endothelial cells. Toxicology 2018; 410:26-40. [DOI: 10.1016/j.tox.2018.09.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/31/2018] [Accepted: 09/06/2018] [Indexed: 12/20/2022]
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106
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PICK1 Deficiency Induces Autophagy Dysfunction via Lysosomal Impairment and Amplifies Sepsis-Induced Acute Lung Injury. Mediators Inflamm 2018; 2018:6757368. [PMID: 30402043 PMCID: PMC6192133 DOI: 10.1155/2018/6757368] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 07/25/2018] [Accepted: 08/02/2018] [Indexed: 12/19/2022] Open
Abstract
Sepsis is a systemic inflammatory reaction caused by infection. Multiple organ failure ultimately leads to high morbidity and mortality. Unfortunately, therapies against these responses have been unsuccessful due to the insufficient underlying pathophysiological evidence. Protein interacting with C-kinase 1 (PICK1) has received considerable attention because of its important physiological functions in many tissues. However, its role in sepsis-induced acute lung injury (ALI) is unclear. In this study, we used cecal ligation and puncture (CLP) to establish a septic model and found that decreased microtubule-associated protein-1light chain 3 (LC3)-II/LC3-I in PICK1−/− septic mice was caused by autophagy dysfunction. Consistently, the transmission electron microscopy (TEM) of bone marrow-derived macrophages (BMDMs) from PICK1−/− mice showed the accumulation of autophagosomes as well. However, more serious damage was caused by PICK1 deficiency indicating that the disrupted autophagic flux was harmful to sepsis-induced ALI. We also observed that it was the impaired lysosomal function that mediated autophagic flux blockade, and the autophagy progress was relevant to PI3K-Akt-mTOR pathway. These findings will aid in the potential development of PICK1 with novel evidence of autophagy in sepsis treatment and prevention.
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107
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Ma K, Zhang Y, Song G, Wu M, Chen G. Identification of Autophagy-Related Gene 7 and Autophagic Cell Death in the Planarian Dugesia japonica. Front Physiol 2018; 9:1223. [PMID: 30233400 PMCID: PMC6131670 DOI: 10.3389/fphys.2018.01223] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 08/14/2018] [Indexed: 12/21/2022] Open
Abstract
Planarians undergo continuous body size remodeling under starvation or during regeneration. This process likely involves autophagy and autophagic cell death, but this hypothesis is supported by few studies. To test this hypothesis, we cloned and characterized autophagy-related gene 7 (Atg7) from the planarian Dugesia japonica (DjAtg7). The full-length cDNA of DjAtg7 measures 2272 bp and includes a 2082-bp open reading frame encoding 693 amino acids with a molecular weight of 79.06 kDa. The deduced amino acid sequence of DjAtg7 contains a conserved ATP-binding site and a catalytic active site of an E1-like enzyme belonging to the ATG7 superfamily. DjAtg7 transcripts are mainly expressed in intestinal tissues of the intact animals. After amputation, DjAtg7 was highly expressed at the newly regenerated intestinal branch on days 3-7 of regeneration and in the old tissue of the distal intestinal branch on day 10 of regeneration. However, knockdown of DjAtg7 by RNAi did not affect planarian regeneration and did not block autophagosome formation, which indicates that autophagy is more complex than previously expected. Interestingly, TEM clearly confirmed that autophagy and autophagic cell death occurred in the old tissues of the newly regenerated planarians and clearly revealed that the dying cell released vesicles containing cellular cytoplasmic contents into the extracellular space. Therefore, the autophagy and autophagic cell death that occurred in the old tissue not only met the demand for body remodeling but also met the demand for energy supply during planarian regeneration. Collectively, our work contributes to the understanding of autophagy and autophagic cell death in planarian regeneration and body remodeling.
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Affiliation(s)
| | | | | | | | - Guangwen Chen
- College of Life Sciences, Henan Normal University, Xinxiang, China
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108
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Yuan YY, Xie KX, Wang SL, Yuan LW. Inflammatory caspase-related pyroptosis: mechanism, regulation and therapeutic potential for inflammatory bowel disease. Gastroenterol Rep (Oxf) 2018; 6:167-176. [PMID: 30151200 PMCID: PMC6101557 DOI: 10.1093/gastro/goy011] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/01/2018] [Accepted: 03/18/2018] [Indexed: 12/22/2022] Open
Abstract
As an essential part of programmed cell death, pyroptosis is an inflammatory response that is elicited upon infection by intracellular pathogens. Metabolic diseases, atherosclerosis and vital organ damage occur if pyroptosis is over-activated. Macrophages are the main cells that induce pyroptosis with the help of intracellular pattern-recognition receptors stimulated by danger signals and pathogenic microorganisms in the cytosol of host cells. Activated inflammatory caspases induce pyroptosis and produce pro-inflammatory cytokines, such as interleukin-1β and interleukin-18. Inflammatory programmed cell death is classified as canonical or non-canonical based on inflammatory caspases, which includes caspase-1 (in human and mouse) and caspase-11 (in mouse) or caspase-4 and -5 (in humans). Activated inflammatory caspases cleave the pore-forming effector protein, gasdermin-D, inducing osmotic pressure deregulation of internal fluids and subsequently rupturing the cell membranes. Inflammatory caspases could be attractive therapeutic targets for inflammatory bowel disease (IBD) in which pyroptosis may play an important role. This article reviews the current understanding of the mechanism of pyroptosis, focusing on the regulation of inflammatory caspases and therapeutic strategies for IBD.
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Affiliation(s)
- Yuan-Yuan Yuan
- Department of Geriatric Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China
| | - Ke-Xin Xie
- Medical Laboratory Technology 1602, Central South University Xiangya School of Medicine, 172 Tongzipo Road, YueLu District, Changsha, Hunan 410011, China
| | - Sha-Long Wang
- Department of Geriatric Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China
| | - Lian-Wen Yuan
- Department of Geriatric Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China
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109
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Li Z, Wang G, Feng D, Zu G, Li Y, Shi X, Zhao Y, Jing H, Ning S, Le W, Yao J, Tian X. Targeting the miR-665-3p-ATG4B-autophagy axis relieves inflammation and apoptosis in intestinal ischemia/reperfusion. Cell Death Dis 2018; 9:483. [PMID: 29706629 PMCID: PMC5924757 DOI: 10.1038/s41419-018-0518-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 02/08/2023]
Abstract
Autophagy is an essential cytoprotective response against pathologic stresses that selectively degrades damaged cellular components. Impaired autophagy contributes to organ injury in multiple diseases, including ischemia/reperfusion (I/R), but the exact mechanism by which impaired autophagy is regulated remains unclear. Several researchers have demonstrated that microRNAs (miRNAs) negatively regulate autophagy by targeting autophagy-related genes (ATGs). Therefore, the effect of ATG-related miRNAs on I/R remains a promising research avenue. In our study, we found that autophagy flux is impaired during intestinal I/R. A miRNA microarray analysis showed that miR-665-3p was highly expressed in the I/R group, which was confirmed by qRT-PCR. Then, we predicted and proved that miR-665-3p negatively regulates ATG4B expression in Caco-2 and IEC-6 cells. In ileum biopsy samples from patients with intestinal infarction, there was an inverse correlation between miR-665-3p and ATG4B expression, which supports the in vitro findings. Moreover, based on miR-665-3p regulation of autophagy in response to hypoxia/reoxygenation in vitro, gain-of-function and loss-of-function approaches were used to investigate the therapeutic potential of miR-665-3p. Additionally, we provide evidence that ATG4B is indispensable for protection upon inhibition of miR-665-3p. Finally, we observed that locked nucleic acid-modified inhibition of miR-665-3p in vivo alleviates I/R-induced systemic inflammation and apoptosis via recovery of autophagic flux. Our study highlights miR-665-3p as a novel small molecule that regulates autophagy by targeting ATG4B, suggesting that miR-665-3p inhibition may be a potential therapeutic approach against inflammation and apoptosis for the clinical treatment of intestinal I/R.
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Affiliation(s)
- Zhenlu Li
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Guangzhi Wang
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Dongcheng Feng
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Guo Zu
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Yang Li
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Xue Shi
- Department of Pharmacology, Dalian Medical University, 116044, Dalian, China
| | - Yan Zhao
- Department of Pharmacology, Dalian Medical University, 116044, Dalian, China
| | - Huirong Jing
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Shili Ning
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China
| | - Weidong Le
- Clinical Research Center on Neurological Diseases, the First Affiliated Hospital of Dalian Medical University, 116011, Dalian, China
| | - Jihong Yao
- Department of Pharmacology, Dalian Medical University, 116044, Dalian, China.
| | - Xiaofeng Tian
- Department of General Surgery, The Second Hospital of Dalian Medical University, 116023, Dalian, China.
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110
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Li Q, Li L, Fei X, Zhang Y, Qi C, Hua S, Gong F, Fang M. Inhibition of autophagy with 3-methyladenine is protective in a lethal model of murine endotoxemia and polymicrobial sepsis. Innate Immun 2018; 24:231-239. [PMID: 29673286 PMCID: PMC6830927 DOI: 10.1177/1753425918771170] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Here, the regulatory role of autophagy is examined in both an LPS-induced lethal
endotoxic shock mouse model and cecal ligation and puncture (CLP) mouse model.
Autophagy-inhibitor 3-methyladenine (3-MA) and autophagy-enhancer rapamycin were
administrated to mice challenged with LPS or CLP. Animals challenged with LPS or
CLP combined with 3-MA displayed increased survival after endotoxemia, but LPS
combined with rapamycin worsened the endotoxic shock of the mice. Among the
different organs studied, the lungs and intestines exhibited significant
differences among LPS alone, LPS combined with 3-MA and LPS combined with
rapamycin. LPS combined with 3-MA attenuated the inflammatory damages of these
organs as compared with LPS alone. In contrast, LPS combined with rapamycin
increased damage in these organs. Consistently, serum inflammatory mediators
TNF-α and IL-6 were decreased by the treatment of LPS combined with 3-MA as
compared with LPS alone, while administration of LPS combined with rapamycin
increased the serum TNF-α and IL-6 levels. Similar results were found in mouse
bone marrow-derived macrophages exposed to LPS. Moreover, the regulatory effect
of autophagy to endotoxic shock is dependent on the TLR4 signaling pathway. Our
results demonstrate the central role of autophagy in the regulation of endotoxic
shock and its potential modulation for endotoxic shock treatment.
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Affiliation(s)
- Qirui Li
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Lingyun Li
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Xiaoyuan Fei
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Yuanyue Zhang
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Chang Qi
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Shuyao Hua
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Feili Gong
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Min Fang
- Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, China
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111
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The Microbial Endocrinology of Pseudomonas aeruginosa: Inflammatory and Immune Perspectives. Arch Immunol Ther Exp (Warsz) 2018. [PMID: 29541797 DOI: 10.1007/s00005-018-0510-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Pseudomonas aeruginosa is a major pathogen responsible for both acute and chronic infection. Known as a colonising pathogen of the cystic fibrosis (CF) lung, it is implicated in other settings such as bronchiectasis. It has the ability to cause acute disseminated or localised infection particularly in the immunocompromised. Human hormones have been highlighted as potential regulators of bacterial virulence through crosstalk between analogous "quorum sensing" (QS) systems present in the bacteria that respond to mammalian hormones. Pseudomonas aeruginosa is known to utilise interconnected QS systems to coordinate its virulence and evade various aspects of the host immune system activated in response to infection. Several human hormones demonstrate an influence on P. aeruginosa growth and virulence. This inter-kingdom signalling, termed "microbial endocrinology" has important implications for host-microbe interaction during infection and, potentially opens up novel avenues for therapeutic intervention. This phenomenon, supported by the existence of sexual dichotomies in both microbial infection and chronic lung diseases such as CF is potentially explained by sex hormones and their influence on the infective process. This review summarises our current understanding of the microbial endocrinology of P. aeruginosa, including its endogenous QS systems and their intersection with human endocrinology, pathogenesis of infection and the host immune system.
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112
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Recent Advances in the Molecular Mechanisms Underlying Pyroptosis in Sepsis. Mediators Inflamm 2018; 2018:5823823. [PMID: 29706799 PMCID: PMC5863298 DOI: 10.1155/2018/5823823] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/22/2018] [Indexed: 12/25/2022] Open
Abstract
Sepsis is recognized as a life-threatening organ dysfunctional disease that is caused by dysregulated host responses to infection. Up to now, sepsis still remains a dominant cause of multiple organ dysfunction syndrome (MODS) and death among severe condition patients. Pyroptosis, originally named after the Greek words “pyro” and “ptosis” in 2001, has been defined as a specific programmed cell death characterized by release of inflammatory cytokines. During sepsis, pyroptosis is required for defense against bacterial infection because appropriate pyroptosis can minimize tissue damage. Even so, pyroptosis when overactivated can result in septic shock, MODS, or increased risk of secondary infection. Proteolytic cleavage of gasdermin D (GSDMD) by caspase-1, caspase-4, caspase-5, and caspase-11 is an essential step for the execution of pyroptosis in activated innate immune cells and endothelial cells stimulated by cytosolic lipopolysaccharide (LPS). Cleaved GSDMD also triggers NACHT, LRR, and PYD domain-containing protein (NLRP) 3-mediated activation of caspase-1 via an intrinsic pathway, while the precise mechanism underlying GSDMD-induced NLRP 3 activation remains unclear. Hence, this study provides an overview of the recent advances in the molecular mechanisms underlying pyroptosis in sepsis.
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113
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Louis C, Burns C, Wicks I. TANK-Binding Kinase 1-Dependent Responses in Health and Autoimmunity. Front Immunol 2018; 9:434. [PMID: 29559975 PMCID: PMC5845716 DOI: 10.3389/fimmu.2018.00434] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 02/19/2018] [Indexed: 01/05/2023] Open
Abstract
The pathogenesis of autoimmune diseases, such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) is driven by genetic predisposition and environmental triggers that lead to dysregulated immune responses. These include the generation of pathogenic autoantibodies and aberrant production of inflammatory cytokines. Current therapies for RA and other autoimmune diseases reduce inflammation by targeting inflammatory mediators, most of which are innate response cytokines, resulting in generalized immunosuppression. Overall, this strategy has been very successful, but not all patients respond, responses can diminish over time and numerous side effects can occur. Therapies that target the germinal center (GC) reaction and/or antibody-secreting plasma cells (PC) potentially provide a novel approach. TANK-binding kinase 1 (TBK1) is an IKK-related serine/threonine kinase best characterized for its involvement in innate antiviral responses through the induction of type I interferons. TBK1 is also gaining attention for its roles in humoral immune responses. In this review, we discuss the role of TBK1 in immunological pathways involved in the development and maintenance of antibody responses, with particular emphasis on its potential relevance in the pathogenesis of humoral autoimmunity. First, we review the role of TBK1 in the induction of type I IFNs. Second, we highlight how TBK1 mediates inducible T cell co-stimulator signaling to the GC T follicular B helper population. Third, we discuss emerging evidence on the contribution of TBK1 to autophagic pathways and the potential implications for immune cell function. Finally, we discuss the therapeutic potential of TBK1 inhibition in autoimmunity.
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Affiliation(s)
- Cynthia Louis
- Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Chris Burns
- Chemical Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Ian Wicks
- Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Rheumatology Unit, Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia
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114
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Racanelli AC, Kikkers SA, Choi AM, Cloonan SM. Autophagy and inflammation in chronic respiratory disease. Autophagy 2018; 14:221-232. [PMID: 29130366 PMCID: PMC5902194 DOI: 10.1080/15548627.2017.1389823] [Citation(s) in RCA: 319] [Impact Index Per Article: 53.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 10/02/2017] [Accepted: 10/05/2017] [Indexed: 12/14/2022] Open
Abstract
Persistent inflammation within the respiratory tract underlies the pathogenesis of numerous chronic pulmonary diseases including chronic obstructive pulmonary disease, asthma and pulmonary fibrosis. Chronic inflammation in the lung may arise from a combination of genetic susceptibility and environmental influences, including exposure to microbes, particles from the atmosphere, irritants, pollutants, allergens, and toxic molecules. To this end, an immediate, strong, and highly regulated inflammatory defense mechanism is needed for the successful maintenance of homeostasis within the respiratory system. Macroautophagy/autophagy plays an essential role in the inflammatory response of the lung to infection and stress. At baseline, autophagy may be critical for inhibiting spontaneous pulmonary inflammation and fundamental for the response of pulmonary leukocytes to infection; however, when not regulated, persistent or inefficient autophagy may be detrimental to lung epithelial cells, promoting lung injury. This perspective will discuss the role of autophagy in driving and regulating inflammatory responses of the lung in chronic lung diseases with a focus on potential avenues for therapeutic targeting. Abbreviations AR allergic rhinitis AM alveolar macrophage ATG autophagy-related CF cystic fibrosis CFTR cystic fibrosis transmembrane conductance regulator COPD chronic obstructive pulmonary disease CS cigarette smoke CSE cigarette smoke extract DC dendritic cell IH intermittent hypoxia IPF idiopathic pulmonary fibrosis ILD interstitial lung disease MAP1LC3B microtubule associated protein 1 light chain 3 beta MTB Mycobacterium tuberculosis MTOR mechanistic target of rapamycin kinase NET neutrophil extracellular traps OSA obstructive sleep apnea PAH pulmonary arterial hypertension PH pulmonary hypertension ROS reactive oxygen species TGFB1 transforming growth factor beta 1 TNF tumor necrosis factor.
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Affiliation(s)
- Alexandra C. Racanelli
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
- New York-Presbyterian Hospital, New York, NY, USA
| | - Sarah Ann Kikkers
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | - Augustine M.K. Choi
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
- New York-Presbyterian Hospital, New York, NY, USA
| | - Suzanne M. Cloonan
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
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115
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Ren C, Zhang H, Wu TT, Yao YM. Autophagy: A Potential Therapeutic Target for Reversing Sepsis-Induced Immunosuppression. Front Immunol 2017; 8:1832. [PMID: 29326712 PMCID: PMC5741675 DOI: 10.3389/fimmu.2017.01832] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 12/04/2017] [Indexed: 01/17/2023] Open
Abstract
Sepsis remains the leading cause of mortality in intensive care units and an intractable condition due to uncontrolled inflammation together with immune suppression. Dysfunction of immune cells is considered as a major cause for poor outcome of septic patients but with little specific treatments. Currently, autophagy that is recognized as an important self-protective mechanism for cellular survival exhibits great potential for maintaining immune homeostasis and alleviating multiple organ failure, which further improves survival of septic animals. The protective effect of autophagy on immune cells covers both innate and adaptive immune responses and refers to various cellular receptors and intracellular signaling. Multiple drugs and measures are reportedly beneficial for septic challenge by inducing autophagy process. Therefore, autophagy might be an effective target for reversing immunosuppression compromised by sepsis.
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Affiliation(s)
- Chao Ren
- Trauma Research Center, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, China.,School of Medicine, Nankai University, Tianjin, China
| | - Hui Zhang
- Trauma Research Center, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, China
| | - Tian-Tian Wu
- Trauma Research Center, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, China
| | - Yong-Ming Yao
- Trauma Research Center, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, China.,School of Medicine, Nankai University, Tianjin, China.,State Key Laboratory of Kidney Disease, The Chinese PLA General Hospital, Beijing, China
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116
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Bah A, Vergne I. Macrophage Autophagy and Bacterial Infections. Front Immunol 2017; 8:1483. [PMID: 29163544 PMCID: PMC5681717 DOI: 10.3389/fimmu.2017.01483] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 10/23/2017] [Indexed: 12/25/2022] Open
Abstract
Autophagy is a well-conserved lysosomal degradation pathway that plays key roles in bacterial infections. One of the most studied is probably xenophagy, the selective capture and degradation of intracellular bacteria by lysosomes. However, the impact of autophagy goes beyond xenophagy and involves intensive cross-talks with other host defense mechanisms. In addition, autophagy machinery can have non-canonical functions such as LC3-associated phagocytosis. In this review, we intend to summarize the current knowledge on the many functions of autophagy proteins in cell defenses with a focus on bacteria–macrophage interaction. We also present the strategies developed by pathogens to evade or to exploit this machinery in order to establish a successful infection. Finally, we discuss the opportunities and challenges of autophagy manipulation in improving therapeutics and vaccines against bacterial pathogens.
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Affiliation(s)
- Aïcha Bah
- Institut de Pharmacologie et de Biologie Structurale, UMR 5089 CNRS-Université de Toulouse, Toulouse, France
| | - Isabelle Vergne
- Institut de Pharmacologie et de Biologie Structurale, UMR 5089 CNRS-Université de Toulouse, Toulouse, France
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Slavin SA, Leonard A, Grose V, Fazal F, Rahman A. Autophagy inhibitor 3-methyladenine protects against endothelial cell barrier dysfunction in acute lung injury. Am J Physiol Lung Cell Mol Physiol 2017; 314:L388-L396. [PMID: 29074492 DOI: 10.1152/ajplung.00555.2016] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autophagy is an evolutionarily conserved cellular process that facilitates the continuous recycling of intracellular components (organelles and proteins) and provides an alternative source of energy when nutrients are scarce. Recent studies have implicated autophagy in many disorders, including pulmonary diseases. However, the role of autophagy in endothelial cell (EC) barrier dysfunction and its relevance in the context of acute lung injury (ALI) remain uncertain. Here, we provide evidence that autophagy is a critical component of EC barrier disruption in ALI. Using an aerosolized bacterial lipopolysaccharide (LPS) inhalation mouse model of ALI, we found that administration of the autophagy inhibitor 3-methyladenine (3-MA), either prophylactically or therapeutically, markedly reduced lung vascular leakage and tissue edema. 3-MA was also effective in reducing the levels of proinflammatory mediators and lung neutrophil sequestration induced by LPS. To test the possibility that autophagy in EC could contribute to lung vascular injury, we addressed its role in the mechanism of EC barrier disruption. Knockdown of ATG5, an essential regulator of autophagy, attenuated thrombin-induced EC barrier disruption, confirming the involvement of autophagy in the response. Similarly, exposure of cells to 3-MA, either before or after thrombin, protected against EC barrier dysfunction by inhibiting the cleavage and loss of vascular endothelial cadherin at adherens junctions, as well as formation of actin stress fibers. 3-MA also reversed LPS-induced EC barrier disruption. Together, these data imply a role of autophagy in lung vascular injury and reveal the protective and therapeutic utility of 3-MA against ALI.
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Affiliation(s)
- Spencer A Slavin
- Department of Pediatrics (Neonatology), Lung Biology and Disease Program, University of Rochester School of Medicine and Dentistry , Rochester, New York
| | - Antony Leonard
- Department of Pediatrics (Neonatology), Lung Biology and Disease Program, University of Rochester School of Medicine and Dentistry , Rochester, New York
| | - Valerie Grose
- Department of Pediatrics (Neonatology), Lung Biology and Disease Program, University of Rochester School of Medicine and Dentistry , Rochester, New York
| | - Fabeha Fazal
- Department of Pediatrics (Neonatology), Lung Biology and Disease Program, University of Rochester School of Medicine and Dentistry , Rochester, New York
| | - Arshad Rahman
- Department of Pediatrics (Neonatology), Lung Biology and Disease Program, University of Rochester School of Medicine and Dentistry , Rochester, New York
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