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Hu T, Liu Y, Fleck J, King C, Schalk E, Zhang Z, Mehle A, Smith JA. Multiple unfolded protein response pathways cooperate to link cytosolic dsDNA release to stimulator of interferon gene activation. Front Immunol 2024; 15:1358462. [PMID: 39100663 PMCID: PMC11294172 DOI: 10.3389/fimmu.2024.1358462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 06/10/2024] [Indexed: 08/06/2024] Open
Abstract
The double-stranded DNA (dsDNA) sensor STING has been increasingly implicated in responses to "sterile" endogenous threats and pathogens without nominal DNA or cyclic di-nucleotide stimuli. Previous work showed an endoplasmic reticulum (ER) stress response, known as the unfolded protein response (UPR), activates STING. Herein, we sought to determine if ER stress generated a STING ligand, and to identify the UPR pathways involved. Induction of IFN-β expression following stimulation with the UPR inducer thapsigargin (TPG) or oxygen glucose deprivation required both STING and the dsDNA-sensing cyclic GMP-AMP synthase (cGAS). Furthermore, TPG increased cytosolic mitochondrial DNA, and immunofluorescence visualized dsDNA punctae in murine and human cells, providing a cGAS stimulus. N-acetylcysteine decreased IFN-β induction by TPG, implicating reactive oxygen species (ROS). However, mitoTEMPO, a mitochondrial oxidative stress inhibitor did not impact TPG-induced IFN. On the other hand, inhibiting the inositol requiring enzyme 1 (IRE1) ER stress sensor and its target transcription factor XBP1 decreased the generation of cytosolic dsDNA. iNOS upregulation was XBP1-dependent, and an iNOS inhibitor decreased cytosolic dsDNA and IFN-β, implicating ROS downstream of the IRE1-XBP1 pathway. Inhibition of the PKR-like ER kinase (PERK) pathway also attenuated cytoplasmic dsDNA release. The PERK-regulated apoptotic factor Bim was required for both dsDNA release and IFN-β mRNA induction. Finally, XBP1 and PERK pathways contributed to cytosolic dsDNA release and IFN-induction by the RNA virus, Vesicular Stomatitis Virus (VSV). Together, our findings suggest that ER stressors, including viral pathogens without nominal STING or cGAS ligands such as RNA viruses, trigger multiple canonical UPR pathways that cooperate to activate STING and downstream IFN-β via mitochondrial dsDNA release.
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Affiliation(s)
- Tiancheng Hu
- Department of Pharmacology and Toxicology, Rutgers University, New Brunswick, NJ, United States
| | - Yiping Liu
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Jeremy Fleck
- Department of Immunology and Microbiology, University of Colorado, Aurora, CO, United States
| | - Cason King
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, United States
| | - Elaine Schalk
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Zhenyu Zhang
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, United States
| | - Andrew Mehle
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, United States
| | - Judith A. Smith
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, United States
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Liu X, Liu M, Wu H, Tang W, Yang W, Chan TTH, Zhang L, Chen S, Xiong Z, Liang J, Wai-Yiu Si-Tou W, Shu T, Li J, Cao J, Zhong C, Sun H, Kwong TT, Leung HHW, Wong J, Bo-San Lai P, To KF, Xiang T, Jao-Yiu Sung J, Chan SL, Zhou J, Sze-Lok Cheng A. PPP1R15A-expressing monocytic MDSCs promote immunosuppressive liver microenvironment in fibrosis-associated hepatocellular carcinoma. JHEP Rep 2024; 6:101087. [PMID: 38882672 PMCID: PMC11179254 DOI: 10.1016/j.jhepr.2024.101087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 03/24/2024] [Accepted: 03/27/2024] [Indexed: 06/18/2024] Open
Abstract
Background & Aims Recent studies demonstrated the importance of fibrosis in promoting an immunosuppressive liver microenvironment and thereby aggressive hepatocellular carcinoma (HCC) growth and resistance to immune checkpoint blockade (ICB), particularly via monocyte-to-monocytic myeloid-derived suppressor cell (M-MDSC) differentiation triggered by hepatic stellate cells (HSCs). We thus aimed to identify druggable targets in these immunosuppressive myeloid cells for HCC therapy. Methods M-MDSC signature genes were identified by integrated transcriptomic analysis of a human HSC-monocyte culture system and tumor-surrounding fibrotic livers of patients with HCC. Mechanistic and functional studies were conducted using in vitro-generated and patient-derived M-MDSCs. The therapeutic efficacy of a M-MDSC targeting approach was determined in fibrosis-associated HCC mouse models. Results We uncovered over-expression of protein phosphatase 1 regulatory subunit 15A (PPP1R15A), a myeloid cell-enriched endoplasmic reticulum stress modulator, in human M-MDSCs that correlated with poor prognosis and ICB non-responsiveness in patients with HCC. Blocking TGF-β signaling reduced PPP1R15A expression in HSC-induced M-MDSCs, whereas treatment of monocytes by TGF-β upregulated PPP1R15A, which in turn promoted ARG1 and S100A8/9 expression in M-MDSCs and reduced T-cell proliferation. Consistently, lentiviral-mediated knockdown of Ppp1r15a in vivo significantly reduced ARG1+S100A8/9+ M-MDSCs in fibrotic liver, leading to elevated intratumoral IFN-γ+GZMB+CD8+ T cells and enhanced anti-tumor efficacy of ICB. Notably, pharmacological inhibition of PPP1R15A by Sephin1 reduced the immunosuppressive potential but increased the maturation status of fibrotic HCC patient-derived M-MDSCs. Conclusions PPP1R15A+ M-MDSC cells are involved in immunosuppression in HCC development and represent a novel potential target for therapies. Impact and implications Our cross-species analysis has identified PPP1R15A as a therapeutic target governing the anti-T-cell activities of fibrosis-associated M-MDSCs (monocytic myeloid-derived suppressor cells). The results from the preclinical models show that specific inhibition of PPP1R15A can break the immunosuppressive barrier to restrict hepatocellular carcinoma growth and enhance the efficacy of immune checkpoint blockade. PPP1R15A may also function as a prognostic and/or predictive biomarker in patients with hepatocellular carcinoma.
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Affiliation(s)
- Xiaoyu Liu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
- Chongqing Key Laboratory for the Mechanism and Intervention of Cancer Metastasis, Chongqing University Cancer Hospital, Chongqing, China
| | - Man Liu
- Department of Gastroenterology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Haoran Wu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Wenshu Tang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Weiqin Yang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Thomas T H Chan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Lingyun Zhang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Shufen Chen
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Zhewen Xiong
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jianxin Liang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Willis Wai-Yiu Si-Tou
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Ting Shu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jingqing Li
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jianquan Cao
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Chengpeng Zhong
- Department of Liver Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hanyong Sun
- Department of Liver Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Tsz Tung Kwong
- Department of Clinical Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong, China
| | - Howard H W Leung
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - John Wong
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China
| | - Paul Bo-San Lai
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China
| | - Ka-Fai To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
- State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Hong Kong, China
| | - Tingxiu Xiang
- Chongqing Key Laboratory for the Mechanism and Intervention of Cancer Metastasis, Chongqing University Cancer Hospital, Chongqing, China
| | - Joseph Jao-Yiu Sung
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Hong Kong, China
| | - Stephen Lam Chan
- Department of Clinical Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong, China
- State Key Laboratory of Translational Oncology, The Chinese University of Hong Kong, Hong Kong, China
| | - Jingying Zhou
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Alfred Sze-Lok Cheng
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
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Hu T, Liu Y, Fleck J, King C, Schalk E, Zhang Z, Mehle A, Smith JA. Multiple Unfolded Protein Response pathways cooperate to link cytosolic dsDNA release to Stimulator of Interferon Gene (STING) activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.10.593557. [PMID: 38798499 PMCID: PMC11118346 DOI: 10.1101/2024.05.10.593557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
The double-stranded DNA (dsDNA) sensor STING has been increasingly implicated in responses to "sterile" endogenous threats and pathogens without nominal DNA or cyclic di-nucleotide stimuli. Previous work showed an endoplasmic reticulum (ER) stress response, known as the unfolded protein response (UPR), activates STING. Herein, we sought to determine if ER stress generated a STING ligand, and to identify the UPR pathways involved. Induction of IFN-β expression following stimulation with the UPR inducer thapsigargin (TPG) or oxygen glucose deprivation required both STING and the dsDNA-sensing cyclic GMP-AMP synthase (cGAS). Furthermore, TPG increased cytosolic mitochondrial DNA, and immunofluorescence visualized dsDNA punctae in murine and human cells, providing a cGAS stimulus. N-acetylcysteine decreased IFN-β induction by TPG, implicating reactive oxygen species (ROS). However, mitoTEMPO, a mitochondrial oxidative stress inhibitor did not impact TPG-induced IFN. On the other hand, inhibiting the inositol requiring enzyme 1 (IRE1) ER stress sensor and its target transcription factor XBP1 decreased the generation of cytosolic dsDNA. iNOS upregulation was XBP1-dependent, and an iNOS inhibitor decreased cytosolic dsDNA and IFN-β, implicating ROS downstream of the IRE1-XBP1 pathway. Inhibition of the PKR-like ER kinase (PERK) pathway also attenuated cytoplasmic dsDNA release. The PERK-regulated apoptotic factor Bim was required for both dsDNA release and IFN-β mRNA induction. Finally, XBP1 and PERK pathways contributed to cytosolic dsDNA release and IFN-induction by the RNA virus, Vesicular Stomatitis Virus (VSV). Together, our findings suggest that ER stressors, including viral pathogens without nominal STING or cGAS ligands such as RNA viruses, trigger multiple canonical UPR pathways that cooperate to activate STING and downstream IFN-β via mitochondrial dsDNA release.
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Smith GR, Zhao B, Lindholm ME, Raja A, Viggars M, Pincas H, Gay NR, Sun Y, Ge Y, Nair VD, Sanford JA, Amper MAS, Vasoya M, Smith KS, Montgomery S, Zaslavsky E, Bodine SC, Esser KA, Walsh MJ, Snyder MP. Multi-omic identification of key transcriptional regulatory programs during endurance exercise training. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.10.523450. [PMID: 36711841 PMCID: PMC9882056 DOI: 10.1101/2023.01.10.523450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Transcription factors (TFs) play a key role in regulating gene expression and responses to stimuli. We conducted an integrated analysis of chromatin accessibility, DNA methylation, and RNA expression across eight rat tissues following endurance exercise training (EET) to map epigenomic changes to transcriptional changes and determine key TFs involved. We uncovered tissue-specific changes and TF motif enrichment across all omic layers, differentially accessible regions (DARs), differentially methylated regions (DMRs), and differentially expressed genes (DEGs). We discovered distinct routes of EET-induced regulation through either epigenomic alterations providing better access for TFs to affect target genes, or via changes in TF expression or activity enabling target gene response. We identified TF motifs enriched among correlated epigenomic and transcriptomic alterations, DEGs correlated with exercise-related phenotypic changes, and EET-induced activity changes of TFs enriched for DEGs among their gene targets. This analysis elucidates the unique transcriptional regulatory mechanisms mediating diverse organ effects of EET.
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Affiliation(s)
- Gregory R Smith
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- These authors contributed equally
| | - Bingqing Zhao
- Department of Genetics, Stanford University, Stanford, CA 94305
- These authors contributed equally
| | - Malene E Lindholm
- Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305
| | - Archana Raja
- Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305
| | - Mark Viggars
- Department of Physiology and Aging, University of Florida, Gainesville, Florida 32610
| | - Hanna Pincas
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Nicole R Gay
- Department of Genetics, Stanford University, Stanford, CA 94305
| | - Yifei Sun
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Yongchao Ge
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Venugopalan D Nair
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - James A Sanford
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Mary Anne S Amper
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Mital Vasoya
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Kevin S Smith
- Department of Genetics, Stanford University, Stanford, CA 94305
- Department of Pathology, Stanford University, Stanford, CA 94305
| | - Stephen Montgomery
- Department of Genetics, Stanford University, Stanford, CA 94305
- Department of Pathology, Stanford University, Stanford, CA 94305
| | - Elena Zaslavsky
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Sue C Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Karyn A Esser
- Department of Physiology and Aging, University of Florida, Gainesville, Florida 32610
| | - Martin J Walsh
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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Brown H, Komnick MR, Brigleb PH, Dermody TS, Esterházy D. Lymph node sharing between pancreas, gut, and liver leads to immune crosstalk and regulation of pancreatic autoimmunity. Immunity 2023; 56:2070-2085.e11. [PMID: 37557168 PMCID: PMC11040372 DOI: 10.1016/j.immuni.2023.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 05/03/2023] [Accepted: 07/12/2023] [Indexed: 08/11/2023]
Abstract
Lymph nodes (LNs) are critical sites for shaping tissue-specific adaptive immunity. However, the impact of LN sharing between multiple organs on such tailoring is less understood. Here, we describe the drainage hierarchy of the pancreas, liver, and the upper small intestine (duodenum) into three murine LNs. Migratory dendritic cells (migDCs), key in instructing adaptive immune outcome, exhibited stronger pro-inflammatory signatures when originating from the pancreas or liver than from the duodenum. Qualitatively different migDC mixing in each shared LN influenced pancreatic β-cell-reactive T cells to acquire gut-homing and tolerogenic phenotypes proportional to duodenal co-drainage. However, duodenal viral infections rendered non-intestinal migDCs and β-cell-reactive T cells more pro-inflammatory in all shared LNs, resulting in elevated pancreatic islet lymphocyte infiltration. Our study uncovers immune crosstalk through LN co-drainage as a powerful force regulating pancreatic autoimmunity.
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Affiliation(s)
- Hailey Brown
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Macy R Komnick
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Pamela H Brigleb
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Terence S Dermody
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA; Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Daria Esterházy
- Department of Pathology, University of Chicago, Chicago, IL, USA.
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Jiang D, Liu H, Zhu G, Li X, Fan L, Zhao F, Xu C, Wang S, Rose Y, Rhen J, Yu Z, Yin Y, Gu Y, Xu X, Fisher EA, Ge J, Xu Y, Pang J. Endothelial PHACTR1 Promotes Endothelial Activation and Atherosclerosis by Repressing PPARγ Activity Under Disturbed Flow in Mice. Arterioscler Thromb Vasc Biol 2023; 43:e303-e322. [PMID: 37199156 PMCID: PMC10524336 DOI: 10.1161/atvbaha.122.318173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 05/02/2023] [Indexed: 05/19/2023]
Abstract
BACKGROUND Numerous genome-wide association studies revealed that SNPs (single nucleotide polymorphisms) at the PHACTR1 (phosphatase and actin regulator 1) locus strongly correlate with coronary artery disease. However, the biological function of PHACTR1 remains poorly understood. Here, we identified the proatherosclerotic effect of endothelial PHACTR1, contrary to macrophage PHACTR1. METHODS We generated global (Phactr1-/-) and endothelial cell (EC)-specific (Phactr1ECKO) Phactr1 KO (knockout) mice and crossed these mice with apolipoprotein E-deficient (Apoe-/-) mice. Atherosclerosis was induced by feeding the high-fat/high-cholesterol diet for 12 weeks or partially ligating carotid arteries combined with a 2-week high-fat/high-cholesterol diet. PHACTR1 localization was identified by immunostaining of overexpressed PHACTR1 in human umbilical vein ECs exposed to different types of flow. The molecular function of endothelial PHACTR1 was explored by RNA sequencing using EC-enriched mRNA from global or EC-specific Phactr1 KO mice. Endothelial activation was evaluated in human umbilical vein ECs transfected with siRNA targeting PHACTR1 and in Phactr1ECKO mice after partial carotid ligation. RESULTS Global or EC-specific Phactr1 deficiency significantly inhibited atherosclerosis in regions of disturbed flow. PHACTR1 was enriched in ECs and located in the nucleus of disturbed flow areas but shuttled to cytoplasm under laminar flow in vitro. RNA sequencing showed that endothelial Phactr1 depletion affected vascular function, and PPARγ (peroxisome proliferator-activated receptor gamma) was the top transcription factor regulating differentially expressed genes. PHACTR1 functioned as a PPARγ transcriptional corepressor by binding to PPARγ through the corepressor motifs. PPARγ activation protects against atherosclerosis by inhibiting endothelial activation. Consistently, PHACTR1 deficiency remarkably reduced endothelial activation induced by disturbed flow in vivo and in vitro. PPARγ antagonist GW9662 abolished the protective effects of Phactr1 KO on EC activation and atherosclerosis in vivo. CONCLUSIONS Our results identified endothelial PHACTR1 as a novel PPARγ corepressor to promote atherosclerosis in disturbed flow regions. Endothelial PHACTR1 is a potential therapeutic target for atherosclerosis treatment.
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Affiliation(s)
- Dongyang Jiang
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Hao Liu
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Guofu Zhu
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Xiankai Li
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Linlin Fan
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Faxue Zhao
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Chong Xu
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Shumin Wang
- Aab Cardiovascular Research Institute, Department of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA (S. W., Y. R., J. R., X. X., J. P.)
| | - Yara Rose
- Aab Cardiovascular Research Institute, Department of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA (S. W., Y. R., J. R., X. X., J. P.)
| | - Jordan Rhen
- Aab Cardiovascular Research Institute, Department of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA (S. W., Y. R., J. R., X. X., J. P.)
| | - Ze Yu
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Yiheng Yin
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Yuling Gu
- Shanghai Naturethink Life Science&Technology Co., Itd, Shanghai 201809, China (Y. G.)
| | - Xiangbin Xu
- Aab Cardiovascular Research Institute, Department of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA (S. W., Y. R., J. R., X. X., J. P.)
| | - Edward A. Fisher
- Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, NY 10016, USA (E. A. F.)
| | - Junbo Ge
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Yawei Xu
- Department of Cardiology, Pan-vascular Research Institute, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China (D. J., H. L., G. Z., X. L., L. F., F. Z., C. X., Z. Y., Y. Y., J. G., Y. X.)
| | - Jinjiang Pang
- Aab Cardiovascular Research Institute, Department of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA (S. W., Y. R., J. R., X. X., J. P.)
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Liu Y, Yao Z, Lian G, Yang P. Biomolecular phase separation in stress granule assembly and virus infection. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1099-1118. [PMID: 37401177 PMCID: PMC10415189 DOI: 10.3724/abbs.2023117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 05/06/2023] [Indexed: 07/05/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) has emerged as a crucial mechanism for cellular compartmentalization. One prominent example of this is the stress granule. Found in various types of cells, stress granule is a biomolecular condensate formed through phase separation. It comprises numerous RNA and RNA-binding proteins. Over the past decades, substantial knowledge has been gained about the composition and dynamics of stress granules. SGs can regulate various signaling pathways and have been associated with numerous human diseases, such as neurodegenerative diseases, cancer, and infectious diseases. The threat of viral infections continues to loom over society. Both DNA and RNA viruses depend on host cells for replication. Intriguingly, many stages of the viral life cycle are closely tied to RNA metabolism in human cells. The field of biomolecular condensates has rapidly advanced in recent times. In this context, we aim to summarize research on stress granules and their link to viral infections. Notably, stress granules triggered by viral infections behave differently from the canonical stress granules triggered by sodium arsenite (SA) and heat shock. Studying stress granules in the context of viral infections could offer a valuable platform to link viral replication processes and host anti-viral responses. A deeper understanding of these biological processes could pave the way for innovative interventions and treatments for viral infectious diseases. They could potentially bridge the gap between basic biological processes and interactions between viruses and their hosts.
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Affiliation(s)
- Yi Liu
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Zhiying Yao
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Guiwei Lian
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Peiguo Yang
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
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Medel B, Bernales JI, Lira A, Fernández D, Iwawaki T, Vargas P, Osorio F. The Unfolded Protein Response Sensor IRE1 Regulates Activation of In Vitro Differentiated Type 1 Conventional DCs with Viral Stimuli. Int J Mol Sci 2023; 24:10205. [PMID: 37373353 DOI: 10.3390/ijms241210205] [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: 05/09/2023] [Revised: 06/01/2023] [Accepted: 06/10/2023] [Indexed: 06/29/2023] Open
Abstract
Type 1 conventional dendritic cells (cDC1s) are leukocytes competent to coordinate antiviral immunity, and thus, the intracellular mechanisms controlling cDC1 function are a matter of intense research. The unfolded protein response (UPR) sensor IRE1 and its associated transcription factor XBP1s control relevant functional aspects in cDC1s including antigen cross-presentation and survival. However, most studies connecting IRE1 and cDC1 function are undertaken in vivo. Thus, the aim of this work is to elucidate whether IRE1 RNase activity can also be modeled in cDC1s differentiated in vitro and reveal the functional consequences of such activation in cells stimulated with viral components. Our data show that cultures of optimally differentiated cDC1s recapitulate several features of IRE1 activation noticed in in vivo counterparts and identify the viral analog Poly(I:C) as a potent UPR inducer in the lineage. In vitro differentiated cDC1s display constitutive IRE1 RNase activity and hyperactivate IRE1 RNase upon genetic deletion of XBP1s, which regulates production of the proinflammatory cytokines IL-12p40, TNF-α and IL-6, Ifna and Ifnb upon Poly(I:C) stimulation. Our results show that a strict regulation of the IRE1/XBP1s axis regulates cDC1 activation to viral agonists, expanding the scope of this UPR branch in potential DC-based therapies.
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Affiliation(s)
- Bernardita Medel
- Laboratory of Immunology and Cellular Stress, Immunology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
| | - José Ignacio Bernales
- Laboratory of Immunology and Cellular Stress, Immunology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
| | - Alonso Lira
- Laboratory of Immunology and Cellular Stress, Immunology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
| | - Dominique Fernández
- Laboratory of Immunology and Cellular Stress, Immunology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
| | - Takao Iwawaki
- Division of Cell Medicine, Department of Life Science, Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Kahoku 920-0293, Ishikawa, Japan
| | - Pablo Vargas
- Leukomotion Lab, Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, F-75015 Paris, France
| | - Fabiola Osorio
- Laboratory of Immunology and Cellular Stress, Immunology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
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9
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Kidwell A, Yadav SPS, Maier B, Zollman A, Ni K, Halim A, Janosevic D, Myslinski J, Syed F, Zeng L, Waffo AB, Banno K, Xuei X, Doud EH, Dagher PC, Hato T. Translation Rescue by Targeting Ppp1r15a through Its Upstream Open Reading Frame in Sepsis-Induced Acute Kidney Injury in a Murine Model. J Am Soc Nephrol 2023; 34:220-240. [PMID: 36283811 PMCID: PMC10103092 DOI: 10.1681/asn.2022060644] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/23/2022] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Translation shutdown is a hallmark of late-phase, sepsis-induced kidney injury. Methods for controlling protein synthesis in the kidney are limited. Reversing translation shutdown requires dephosphorylation of the eukaryotic initiation factor 2 (eIF2) subunit eIF2 α ; this is mediated by a key regulatory molecule, protein phosphatase 1 regulatory subunit 15A (Ppp1r15a), also known as GADD34. METHODS To study protein synthesis in the kidney in a murine endotoxemia model and investigate the feasibility of translation control in vivo by boosting the protein expression of Ppp1r15a, we combined multiple tools, including ribosome profiling (Ribo-seq), proteomics, polyribosome profiling, and antisense oligonucleotides, and a newly generated Ppp1r15a knock-in mouse model and multiple mutant cell lines. RESULTS We report that translation shutdown in established sepsis-induced kidney injury is brought about by excessive eIF2 α phosphorylation and sustained by blunted expression of the counter-regulatory phosphatase Ppp1r15a. We determined the blunted Ppp1r15a expression persists because of the presence of an upstream open reading frame (uORF). Overcoming this barrier with genetic and antisense oligonucleotide approaches enabled the overexpression of Ppp1r15a, which salvaged translation and improved kidney function in an endotoxemia model. Loss of this uORF also had broad effects on the composition and phosphorylation status of the immunopeptidome-peptides associated with the MHC-that extended beyond the eIF2 α axis. CONCLUSIONS We found Ppp1r15a is translationally repressed during late-phase sepsis because of the existence of an uORF, which is a prime therapeutic candidate for this strategic rescue of translation in late-phase sepsis. The ability to accurately control translation dynamics during sepsis may offer new paths for the development of therapies at codon-level precision. PODCAST This article contains a podcast at.
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Affiliation(s)
- Ashley Kidwell
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | | | - Bernhard Maier
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Amy Zollman
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Kevin Ni
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Arvin Halim
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Danielle Janosevic
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jered Myslinski
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Farooq Syed
- Department of Pediatrics and the Herman B. Wells Center, Indiana University School of Medicine, Indianapolis, Indiana
| | - Lifan Zeng
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Alain Bopda Waffo
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Kimihiko Banno
- Department of Physiology, Nara Medical University, Kashihara, Japan
| | - Xiaoling Xuei
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Emma H. Doud
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Pierre C. Dagher
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Takashi Hato
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
- Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana
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GADD34 Ablation Exacerbates Retinal Degeneration in P23H RHO Mice. Int J Mol Sci 2022; 23:ijms232213748. [PMID: 36430227 PMCID: PMC9697375 DOI: 10.3390/ijms232213748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/01/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
The UPR is sustainably activated in degenerating retinas, leading to translational inhibition via p-eIF2α. Recent findings have demonstrated that ablation of growth arrest and DNA damage-inducible protein 34 (GADD34), a protein phosphatase 1 regulatory subunit permitting translational machinery operation through p-eIF2α elevation, does not impact the rate of translation in fast-degenerating rd16 mice. The current study aimed to validate whether P23H RHO mice degenerating at a slower pace manifest translational attenuation and whether GADD34 ablation impacts the rate of retinal degeneration via further suppression of retinal protein synthesis and apoptotic cell death. For this study, mice were examined with ERG and histological analyses. The molecular assessment was conducted in the naïve and LPS-challenged mice using Western blot and qRT-PCR analyses. Thus, this study demonstrates that the P23H RHO retinas manifest translational attenuation. However, GADD34 ablation resulted in a more prominent p-eIF2a increase without impacting the translation rate. GADD34 deficiency also led to a reduction in scotopic ERG amplitudes and an increased number of TUNEL-positive cells. Molecular analysis revealed that GADD34 deficiency reduces the expression of p-STAT3 and Il-6 while increasing the expression of Tnfa. Overall, the data indicate that GADD34 plays a multifunctional role. Under chronic UPR activation, GADD34 acts as a feedback player, dephosphorylating p-eIF2a, although this role does not seem to be critical. Additionally, GADD34 controls cytokine expression and STAT3 activation. Perhaps these molecular events are particularly important in controlling the pace of retinal degeneration.
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Adachi Y, Masuda M, Sakakibara I, Uchida T, Niida Y, Mori Y, Kamei Y, Okumura Y, Ohminami H, Ohnishi K, Yamanaka-Okumura H, Nikawa T, Taketani Y. All-trans retinoic acid changes muscle fiber type via increasing GADD34 dependent on MAPK signal. Life Sci Alliance 2022; 5:5/7/e202101345. [PMID: 35318262 PMCID: PMC8960774 DOI: 10.26508/lsa.202101345] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 11/25/2022] Open
Abstract
ATRA increases GADD34 expression by decreasing the expression of Six1, which down-regulates the transcriptional activity with TLE3 and increasing mRNA stability through blocking the interaction between TTP and ARE on GADD34 mRNA, resulting in muscle fiber type change. All-trans retinoic acid (ATRA) increases the sensitivity to unfolded protein response in differentiating leukemic blasts. The downstream transcriptional factor of PERK, a major arm of unfolded protein response, regulates muscle differentiation. However, the role of growth arrest and DNA damage-inducible protein 34 (GADD34), one of the downstream factors of PERK, and the effects of ATRA on GADD34 expression in muscle remain unclear. In this study, we identified ATRA increased the GADD34 expression independent of the PERK signal in the gastrocnemius muscle of mice. ATRA up-regulated GADD34 expression through the transcriptional activation of GADD34 gene via inhibiting the interaction of homeobox Six1 and transcription co-repressor TLE3 with the MEF3-binding site on the GADD34 gene promoter in skeletal muscle. ATRA also inhibited the interaction of TTP, which induces mRNA degradation, with AU-rich element on GADD34 mRNA via p-38 MAPK, resulting in the instability of GADD34 mRNA. Overexpressed GADD34 in C2C12 cells changes the type of myosin heavy chain in myotubes. These results suggest ATRA increases GADD34 expression via transcriptional and post-transcriptional regulation, which changes muscle fiber type.
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Affiliation(s)
- Yuichiro Adachi
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Masashi Masuda
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Iori Sakakibara
- Department of Nutritional Physiology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Takayuki Uchida
- Department of Nutritional Physiology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yuki Niida
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yuki Mori
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yuki Kamei
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yosuke Okumura
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hirokazu Ohminami
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kohta Ohnishi
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hisami Yamanaka-Okumura
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Takeshi Nikawa
- Department of Nutritional Physiology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yutaka Taketani
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
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12
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Spatial Transcriptomic Analysis Using R-Based Computational Machine Learning Reveals the Genetic Profile of Yang or Yin Deficiency Syndrome in Chinese Medicine Theory. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:5503181. [PMID: 35341155 PMCID: PMC8942619 DOI: 10.1155/2022/5503181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 02/18/2022] [Indexed: 11/27/2022]
Abstract
Objectives Yang and Yin are two main concepts responsible for harmonious balance reflecting health conditions based on Chinese medicine theory. Of note, deficiency of either Yang or Yin is associated with disease susceptibility. In this study, we aim to clarify the molecular feature of Yang and Yin deficiency by reanalyzing a transcriptomic data set retrieved from the GEO database using R-based machine learning analyses, which lays a foundation for medical diagnosis, prevention, and treatment of unbalanced Yang or Yin. Methods Besides conventional methods for target mining, we took the advantage of spatial transcriptomic analysis using R-based machine learning approaches to elucidate molecular profiles of Yin and Yang deficiency by reanalyzing an RNA-Seq data set (GSE87474) in the GEO focusing on peripheral blood mononuclear cells (PBMCs). The add-on functions in R including GEOquery, DESeq2, WGCNA (target identification with a scale-free topological assumption), Scatterplot3d, Tidyverse, and UpsetR were used. For information in the selected GEO data set, PBMCs representing 20,740 expressed genes were collected from subjects with Yang or Yin deficiency (n = 12 each), based on Chinese medicine-related diagnostic criteria. Results The symptomatic gene targets for Yang deficiency (KAT2B, NFKB2, CREBBP, GTF2H3) or Yin deficiency (JUNB, JUND, NGLY1, TNF, RAF1, PPP1R15A) were potentially discovered. CREBBP was identified as a shared key contributive gene regulating either the Yang or Yin deficiency group. The intrinsic molecular characteristics of these specific genes could link with clinical observations of Yang/Yin deficiency, in which Yang deficiency is associated with immune dysfunction tendency and energy deregulation, while Yin deficiency mainly contains oxidative stress, dysfunction of the immune system, and abnormal lipid/protein metabolism. Conclusion Our study provides representative gene targets and modules for supporting clinical traits of Yang or Yin deficiency in Chinese medicine theory, which is beneficial for promoting the modernization of Chinese medicine theory. Besides, R-based machine learning approaches adopted in this study might be further applied for investigating the underlying genetic polymorphisms related to Chinese medicine theory.
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Modulation of the mTOR pathway plays a central role in dendritic cell functions after Echinococcus granulosus antigen recognition. Sci Rep 2021; 11:17238. [PMID: 34446757 PMCID: PMC8390662 DOI: 10.1038/s41598-021-96435-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 07/09/2021] [Indexed: 12/12/2022] Open
Abstract
Immune evasion is a hallmark of persistent echinococcal infection, comprising modulation of innate immune cells and antigen-specific T cell responses. However, recognition of Echinococcus granulosus by dendritic cells (DCs) is a key determinant of the host's response to this parasite. Given that mTOR signaling pathway has been described as a regulator linking metabolism and immune function in DCs, we reported for the first time in these cells, global translation levels, antigen uptake, phenotype, cytokine transcriptional levels, and splenocyte priming activity upon recognition of the hydatid fluid (HF) and the highly glycosylated laminar layer (LL). We found that LL induced a slight up-regulation of CD86 and MHC II in DCs and also stimulated the production of IL-6 and TNF-α. By contrast, HF did not increase the expression of any co-stimulatory molecules, but also down-modulated CD40 and stimulated the expression of the anti-inflammatory cytokine IL-10. Both parasitic antigens promoted protein synthesis through mTOR activation. The use of rapamycin decreased the expression of the cytokines tested, empowered the down-modulation of CD40 and also reduced splenocyte proliferation. Finally, we showed that E. granulosus antigens increase the amounts of LC3-positive structures in DCs which play critical roles in the presentation of these antigens to T cells.
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14
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Siri M, Dastghaib S, Zamani M, Rahmani-Kukia N, Geraylow KR, Fakher S, Keshvarzi F, Mehrbod P, Ahmadi M, Mokarram P, Coombs KM, Ghavami S. Autophagy, Unfolded Protein Response, and Neuropilin-1 Cross-Talk in SARS-CoV-2 Infection: What Can Be Learned from Other Coronaviruses. Int J Mol Sci 2021; 22:5992. [PMID: 34206057 PMCID: PMC8199451 DOI: 10.3390/ijms22115992] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 05/28/2021] [Indexed: 02/07/2023] Open
Abstract
The COVID-19 pandemic is caused by the 2019-nCoV/SARS-CoV-2 virus. This severe acute respiratory syndrome is currently a global health emergency and needs much effort to generate an urgent practical treatment to reduce COVID-19 complications and mortality in humans. Viral infection activates various cellular responses in infected cells, including cellular stress responses such as unfolded protein response (UPR) and autophagy, following the inhibition of mTOR. Both UPR and autophagy mechanisms are involved in cellular and tissue homeostasis, apoptosis, innate immunity modulation, and clearance of pathogens such as viral particles. However, during an evolutionary arms race, viruses gain the ability to subvert autophagy and UPR for their benefit. SARS-CoV-2 can enter host cells through binding to cell surface receptors, including angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP1). ACE2 blockage increases autophagy through mTOR inhibition, leading to gastrointestinal complications during SARS-CoV-2 virus infection. NRP1 is also regulated by the mTOR pathway. An increased NRP1 can enhance the susceptibility of immune system dendritic cells (DCs) to SARS-CoV-2 and induce cytokine storm, which is related to high COVID-19 mortality. Therefore, signaling pathways such as mTOR, UPR, and autophagy may be potential therapeutic targets for COVID-19. Hence, extensive investigations are required to confirm these potentials. Since there is currently no specific treatment for COVID-19 infection, we sought to review and discuss the important roles of autophagy, UPR, and mTOR mechanisms in the regulation of cellular responses to coronavirus infection to help identify new antiviral modalities against SARS-CoV-2 virus.
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Affiliation(s)
- Morvarid Siri
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
| | - Sanaz Dastghaib
- Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, Shiraz 7193635899, Iran;
| | - Mozhdeh Zamani
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
| | - Nasim Rahmani-Kukia
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | | | - Shima Fakher
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Fatemeh Keshvarzi
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Parvaneh Mehrbod
- Influenza and Respiratory Viruses Department, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Mazaher Ahmadi
- Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6517838695, Iran;
| | - Pooneh Mokarram
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Kevin M. Coombs
- Department of Medical Microbiology and Infectious Diseases, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
| | - Saeid Ghavami
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
- Faculty of Medicine, Katowice School of Technology, 40-555 Katowice, Poland
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15
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Zhu QC, Li S, Yuan LX, Chen RA, Liu DX, Fung TS. Induction of the Proinflammatory Chemokine Interleukin-8 Is Regulated by Integrated Stress Response and AP-1 Family Proteins Activated during Coronavirus Infection. Int J Mol Sci 2021; 22:ijms22115646. [PMID: 34073283 PMCID: PMC8198748 DOI: 10.3390/ijms22115646] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/08/2021] [Accepted: 05/20/2021] [Indexed: 01/08/2023] Open
Abstract
Infection induces the production of proinflammatory cytokines and chemokines such as interleukin-8 (IL-8) and IL-6. Although they facilitate local antiviral immunity, their excessive release leads to life-threatening cytokine release syndrome, exemplified by the severe cases of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, we investigated the roles of the integrated stress response (ISR) and activator protein-1 (AP-1) family proteins in regulating coronavirus-induced IL-8 and IL-6 upregulation. The mRNA expression of IL-8 and IL-6 was significantly induced in cells infected with infectious bronchitis virus (IBV), a gammacoronavirus, and porcine epidemic diarrhea virus, an alphacoronavirus. Overexpression of a constitutively active phosphomimetic mutant of eukaryotic translation initiation factor 2α (eIF2α), chemical inhibition of its dephosphorylation, or overexpression of its upstream double-stranded RNA-dependent protein kinase (PKR) significantly enhanced IL-8 mRNA expression in IBV-infected cells. Overexpression of the AP-1 protein cJUN or its upstream kinase also increased the IBV-induced IL-8 mRNA expression, which was synergistically enhanced by overexpression of cFOS. Taken together, this study demonstrated the important regulatory roles of ISR and AP-1 proteins in IL-8 production during coronavirus infection, highlighting the complex interactions between cellular stress pathways and the innate immune response.
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Affiliation(s)
- Qing Chun Zhu
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; (Q.C.Z.); (S.L.); (L.X.Y.)
| | - Shumin Li
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; (Q.C.Z.); (S.L.); (L.X.Y.)
| | - Li Xia Yuan
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; (Q.C.Z.); (S.L.); (L.X.Y.)
| | - Rui Ai Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China;
- Zhaoqing Branch, Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526000, China
| | - Ding Xiang Liu
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; (Q.C.Z.); (S.L.); (L.X.Y.)
- Zhaoqing Branch, Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology, Zhaoqing 526000, China
- Correspondence: or (D.X.L.); (T.S.F.)
| | - To Sing Fung
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; (Q.C.Z.); (S.L.); (L.X.Y.)
- Correspondence: or (D.X.L.); (T.S.F.)
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16
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Straughn AR, Kelm NQ, Kakar SS. Withaferin A and Ovarian Cancer Antagonistically Regulate Skeletal Muscle Mass. Front Cell Dev Biol 2021; 9:636498. [PMID: 33718372 PMCID: PMC7947350 DOI: 10.3389/fcell.2021.636498] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/05/2021] [Indexed: 01/06/2023] Open
Abstract
Cachexia is a complex wasting syndrome that overwhelmingly affects the majority of late-stage cancer patients. Additionally, there are currently no efficacious therapeutic agents to treat the muscle atrophy induced by the cancer. While several preclinical studies have investigated the molecular signals orchestrating cachexia, very little information exists pertaining to ovarian cancer and the associated cachexia. Work from our lab has recently demonstrated that the steroidal lactone Withaferin A (WFA) is capable of attenuating the atrophying effects of ovarian cancer in a preclinical mouse model. However, it remained to be determined whether WFA's effect was in response to its anti-tumorigenic properties, or if it was capable of targeting skeletal muscle directly. The purpose of this study was to uncover whether WFA was capable of regulating muscle mass under tumor-free and tumor-bearing conditions. Treatment with WFA led to an improvement in functional muscle strength and mass under tumor-bearing and naïve conditions. WFA and ovarian cancer were observed to act antagonistically upon critical skeletal muscle regulatory systems, notably myogenic progenitors and proteolytic degradation pathways. Our results demonstrated for the first time that, while WFA has anti-tumorigenic properties, it also exerts hypertrophying effects on skeletal muscle mass, suggesting that it could be an anti-cachectic agent in the settings of ovarian cancer.
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Affiliation(s)
- Alex R. Straughn
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Natia Q. Kelm
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Sham S. Kakar
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
- Department of Physiology, University of Louisville, Louisville, KY, United States
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Poncet AF, Bosteels V, Hoffmann E, Chehade S, Rennen S, Huot L, Peucelle V, Maréchal S, Khalife J, Blanchard N, Janssens S, Marion S. The UPR sensor IRE1α promotes dendritic cell responses to control Toxoplasma gondii infection. EMBO Rep 2021; 22:e49617. [PMID: 33586853 DOI: 10.15252/embr.201949617] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 01/23/2023] Open
Abstract
The unfolded protein response (UPR) has emerged as a central regulator of immune cell responses in several pathologic contexts including infections. However, how intracellular residing pathogens modulate the UPR in dendritic cells (DCs) and thereby affect T cell-mediated immunity remains uncharacterized. Here, we demonstrate that infection of DCs with Toxoplasma gondii (T. gondii) triggers a unique UPR signature hallmarked by the MyD88-dependent activation of the IRE1α pathway and the inhibition of the ATF6 pathway. Induction of XBP1s controls pro-inflammatory cytokine secretion in infected DCs, while IRE1α promotes MHCI antigen presentation of secreted parasite antigens. In mice, infection leads to a specific activation of the IRE1α pathway, which is restricted to the cDC1 subset. Mice deficient for IRE1α and XBP1 in DCs display a severe susceptibility to T. gondii and succumb during the acute phase of the infection. This early mortality is correlated with increased parasite burden and a defect in splenic T-cell responses. Thus, we identify the IRE1α/XBP1s branch of the UPR as a key regulator of host defense upon T. gondii infection.
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Affiliation(s)
- Anaïs F Poncet
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Victor Bosteels
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Eik Hoffmann
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Sylia Chehade
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Sofie Rennen
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Ludovic Huot
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Véronique Peucelle
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Sandra Maréchal
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Jamal Khalife
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Nicolas Blanchard
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, UPS, Université de Toulouse, Toulouse, France
| | - Sophie Janssens
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Sabrina Marion
- Univ. Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, Lille, France
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18
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Mendes A, Gigan JP, Rodriguez Rodrigues C, Choteau SA, Sanseau D, Barros D, Almeida C, Camosseto V, Chasson L, Paton AW, Paton JC, Argüello RJ, Lennon-Duménil AM, Gatti E, Pierre P. Proteostasis in dendritic cells is controlled by the PERK signaling axis independently of ATF4. Life Sci Alliance 2020; 4:4/2/e202000865. [PMID: 33443099 PMCID: PMC7756897 DOI: 10.26508/lsa.202000865] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/10/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022] Open
Abstract
Differentiated dendritic cells display an unusual activation of the integrated stress response, which is necessary for normal type-I Interferon production and cell migration. In stressed cells, phosphorylation of eukaryotic initiation factor 2α (eIF2α) controls transcriptome-wide changes in mRNA translation and gene expression known as the integrated stress response. We show here that DCs are characterized by high eIF2α phosphorylation, mostly caused by the activation of the ER kinase PERK (EIF2AK3). Despite high p-eIF2α levels, DCs display active protein synthesis and no signs of a chronic integrated stress response. This biochemical specificity prevents translation arrest and expression of the transcription factor ATF4 during ER-stress induction by the subtilase cytotoxin (SubAB). PERK inactivation, increases globally protein synthesis levels and regulates IFN-β expression, while impairing LPS-stimulated DC migration. Although the loss of PERK activity does not impact DC development, the cross talk existing between actin cytoskeleton dynamics; PERK and eIF2α phosphorylation is likely important to adapt DC homeostasis to the variations imposed by the immune contexts.
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Affiliation(s)
- Andreia Mendes
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Julien P Gigan
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Christian Rodriguez Rodrigues
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Sébastien A Choteau
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Aix-Marseille Université, INSERM, Theories and Approaches of Genomic Complexity (TAGC), CENTURI, Marseille, France
| | - Doriane Sanseau
- INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Daniela Barros
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Catarina Almeida
- Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Voahirana Camosseto
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Lionel Chasson
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France
| | - Adrienne W Paton
- Department of Molecular and Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - James C Paton
- Department of Molecular and Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - Rafael J Argüello
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | | | - Evelina Gatti
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France .,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
| | - Philippe Pierre
- Aix Marseille Université, Centre National de la Recherch Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Centre d'Immunologie de Marseille Luminy (CIML), CENTURI, Marseille, France .,Department of Medical Sciences, Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA) CNRS "Mistra", Marseille, France.,INSERM U932, Institut Curie, ANR-10-IDEX-0001-02 PSL* and ANR-11-LABX-0043, Paris, France
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19
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Mukherjee D, Bercz LS, Torok MA, Mace TA. Regulation of cellular immunity by activating transcription factor 4. Immunol Lett 2020; 228:24-34. [PMID: 33002512 DOI: 10.1016/j.imlet.2020.09.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/10/2020] [Accepted: 09/22/2020] [Indexed: 02/06/2023]
Abstract
Activating transcription factor 4 (ATF4) is a DNA binding transcription factor belonging to the family of basic Leucine zipper proteins. ATF4 can be activated in response to multiple cellular stress signals including endoplasmic reticulum stress in the event of improper protein folding or oxidative stress because of mitochondrial dysfunction as well as hypoxia. There are multiple downstream targets of ATF4 that can coordinate the regulation between survival and apoptosis of a cell based on time and exposure to stress. ATF4, therefore, has a broad range of control that results in the modulation of immune cells of the innate and adaptive responses leading to regulation of the cellular immunity. Studies provide evidence that ATF4 can regulate immune cells such as macrophages, T cells, B cells, NK cells and dendritic cells contributing to progression of disease. Immune cells can be exposed to stressed environment in the event of a pathogen attack, infection, inflammation, or in the tumor microenvironment leading to increased ATF4 activity to regulate these responses. ATF4 can further control differentiation and maturation of different immune cell types becoming a determinant of effective immune regulation. Additionally, ATF4 has been heavily implicated in rendering effector immune cells dysfunctional that are used to target tumorigenesis. Therefore, there is a need to evaluate where the literature stands in understanding the overall role of ATF4 in regulating cellular immunity to identify therapeutic targets and generalized mechanisms for different disease progressions.
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Affiliation(s)
- Debasmita Mukherjee
- The James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States
| | - Lena S Bercz
- The James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States
| | - Molly A Torok
- The James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States
| | - Thomas A Mace
- The James Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States; Department of Internal Medicine, Division of Gastroenterology, Hepatology and Nutrition, The Ohio State University, Columbus, OH, United States.
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20
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Ghadge GD, Sonobe Y, Camarena A, Drigotas C, Rigo F, Ling KK, Roos RP. Knockdown of GADD34 in neonatal mutant SOD1 mice ameliorates ALS. Neurobiol Dis 2020; 136:104702. [PMID: 31837419 DOI: 10.1016/j.nbd.2019.104702] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/26/2019] [Accepted: 12/08/2019] [Indexed: 11/19/2022] Open
Abstract
Mutations in Cu/Zn superoxide dismutase (SOD1) cause ~20% of familial ALS (FALS), which comprises 10% of total ALS cases. In mutant SOD1- (mtSOD1-) induced ALS, misfolded aggregates of SOD1 lead to activation of the unfolded protein response/integrated stress response (UPR/ISR). Protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), a kinase that phosphorylates eukaryotic translation initiator factor 2α (p-eIF2α), coordinates the response by causing a global suppression of protein synthesis. Growth arrest and DNA damage 34 (GADD34) dephosphorylates p-eIF2α, allowing protein synthesis to return to normal. If the UPR/ISR is overwhelmed by the amount of misfolded protein, CCAAT/enhancer-binding homologous protein (CHOP) is activated leading to apoptosis. In the current study we investigated the effect of knocking down CHOP and GADD34 on disease of G93A and G85R mtSOD1 mice. Although a CHOP antisense oligonucleotide had no effect on survival, an intravenous injection of GADD34 shRNA encoded in adeno-associated virus 9 (AAV9) into neonatal G93A as well as neonatal G85R mtSOD1 mice led to a significantly increased survival. G85R mtSOD1 mice had a reduction in SOD1 aggregates/load, astrocytosis, and microgliosis. In contrast, there was no change in disease phenotype when GADD34 shRNA was delivered to older G93A mtSOD1 mice. Our current study shows that GADD34 shRNA is effective in ameliorating disease when administered to neonatal mtSOD1 mice. Targeting the UPR/ISR may be beneficial in mtSOD1-induced ALS as well as other neurodegenerative diseases in which misfolded proteins and ER stress have been implicated.
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Affiliation(s)
- Ghanashyam D Ghadge
- Department of Neurology, University of Chicago Medical Center, Chicago, IL 60637, United States of America
| | - Yoshifumi Sonobe
- Department of Neurology, University of Chicago Medical Center, Chicago, IL 60637, United States of America
| | - Adrian Camarena
- Department of Neurology, University of Chicago Medical Center, Chicago, IL 60637, United States of America
| | - Claire Drigotas
- Department of Neurology, University of Chicago Medical Center, Chicago, IL 60637, United States of America
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 90201, United States of America
| | - Karen K Ling
- Ionis Pharmaceuticals, Carlsbad, CA 90201, United States of America
| | - Raymond P Roos
- Department of Neurology, University of Chicago Medical Center, Chicago, IL 60637, United States of America.
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21
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Imai J, Otani M, Sakai T. Distinct Subcellular Compartments of Dendritic Cells Used for Cross-Presentation. Int J Mol Sci 2019; 20:ijms20225606. [PMID: 31717517 PMCID: PMC6888166 DOI: 10.3390/ijms20225606] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/29/2019] [Accepted: 11/06/2019] [Indexed: 02/06/2023] Open
Abstract
Dendritic cells (DCs) present exogenous protein-derived peptides on major histocompatibility complex class I molecules to prime naïve CD8+ T cells. This DC specific ability, called cross-presentation (CP), is important for the activation of cell-mediated immunity and the induction of self-tolerance. Recent research revealed that endoplasmic reticulum-associated degradation (ERAD), which was first identified as a part of the unfolded protein response—a quality control system in the ER—plays a pivotal role in the processing of exogenous proteins in CP. Moreover, DCs express a variety of immuno-modulatory molecules and cytokines to regulate T cell activation in response to the environment. Although both CP and immuno-modulation are indispensable, contrasting ER conditions are required for their correct activity. Since ERAD substrates are unfolded proteins, their accumulation may result in ER stress, impaired cell homeostasis, and eventually apoptosis. In contrast, activation of the unfolded protein response should be inhibited for DCs to express immuno-modulatory molecules and cytokines. Here, we review recent advances on antigen CP, focusing on intracellular transport routes for exogenous antigens and distinctive subcellular compartments involved in ERAD.
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Affiliation(s)
- Jun Imai
- Correspondence: ; Tel.: +81-27-352-1180
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22
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Polymerase III transcription is necessary for T cell priming by dendritic cells. Proc Natl Acad Sci U S A 2019; 116:22721-22729. [PMID: 31636192 DOI: 10.1073/pnas.1904396116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Exposure to microbe-associated molecular patterns (MAMPs) causes dendritic cells (DCs) to undergo a remarkable activation process characterized by changes in key biochemical mechanisms. These enhance antigen processing and presentation, as well as strengthen DC capacity to stimulate naïve T cell proliferation. Here, we show that in response to the MAMPS lipopolysaccharide and polyriboinosinic:polyribocytidylic acid (Poly I:C), RNA polymerase III (Pol lII)-dependent transcription and consequently tRNA gene expression are strongly induced in DCs. This is in part caused by the phosphorylation and nuclear export of MAF1 homolog negative regulator of Poll III (MAF1), via a synergistic casein kinase 2 (CK2)- and mammalian target of rapamycin-dependent signaling cascade downstream of Toll-like receptors (TLRs). De novo tRNA expression is necessary to augment protein synthesis and compensate for tRNA degradation driven by TLR-dependent DC exposure to type-I IFN. Although protein synthesis is not strongly inhibited in absence of RNA Pol III activity, it compromises the translation of key DC mRNAs, like those coding for costimulatory molecules and proinflammatory cytokines, which instead can be stored in stress granules, as shown for CD86 mRNA. TLR-dependent CK2 stimulation and subsequent RNA Pol III activation are therefore key for the acquisition by DCs of their unique T cell immune-stimulatory functions.
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23
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Jasenosky LD, Cadena C, Mire CE, Borisevich V, Haridas V, Ranjbar S, Nambu A, Bavari S, Soloveva V, Sadukhan S, Cassell GH, Geisbert TW, Hur S, Goldfeld AE. The FDA-Approved Oral Drug Nitazoxanide Amplifies Host Antiviral Responses and Inhibits Ebola Virus. iScience 2019; 19:1279-1290. [PMID: 31402258 PMCID: PMC6831822 DOI: 10.1016/j.isci.2019.07.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/03/2019] [Accepted: 06/28/2019] [Indexed: 12/24/2022] Open
Abstract
Here, we show that the US Food and Drug Administration-approved oral drug nitazoxanide (NTZ) broadly amplifies the host innate immune response to viruses and inhibits Ebola virus (EBOV) replication. We find that NTZ enhances retinoic-acid-inducible protein I (RIG-I)-like-receptor, mitochondrial antiviral signaling protein, interferon regulatory factor 3, and interferon activities and induces transcription of the antiviral phosphatase GADD34. NTZ significantly inhibits EBOV replication in human cells through its effects on RIG-I and protein kinase R (PKR), suggesting that it counteracts EBOV VP35 protein's ability to block RIG-I and PKR sensing of EBOV. NTZ also inhibits a second negative-strand RNA virus, vesicular stomatitis virus (VSV), through RIG-I and GADD34, but not PKR, consistent with VSV's distinct host innate immune evasion mechanisms. Thus, NTZ counteracts varied virus-specific immune evasion strategies by generally enhancing the RNA sensing and interferon axis that is triggered by foreign cytoplasmic RNA exposure, and holds promise as an oral therapy against EBOV. NTZ amplifies RNA sensor and type I interferon activities and induces GADD34 expression NTZ inhibits infectious Ebola virus (EBOV) via RIG-I and PKR, but not GADD34 NTZ inhibits a second negative-strand RNA virus, VSV, via RIG-I and GADD34, but not PKR NTZ holds promise as an oral therapy against EBOV
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Affiliation(s)
- Luke D Jasenosky
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Cristhian Cadena
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Chad E Mire
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Viktoriya Borisevich
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Viraga Haridas
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Shahin Ranjbar
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Aya Nambu
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Sina Bavari
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
| | - Veronica Soloveva
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
| | - Supriya Sadukhan
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Gail H Cassell
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Thomas W Geisbert
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Sun Hur
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA
| | - Anne E Goldfeld
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA; Infectious Disease Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
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24
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Abstract
Human coronavirus (HCoV) infection causes respiratory diseases with mild to severe outcomes. In the last 15 years, we have witnessed the emergence of two zoonotic, highly pathogenic HCoVs: severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Replication of HCoV is regulated by a diversity of host factors and induces drastic alterations in cellular structure and physiology. Activation of critical signaling pathways during HCoV infection modulates the induction of antiviral immune response and contributes to the pathogenesis of HCoV. Recent studies have begun to reveal some fundamental aspects of the intricate HCoV-host interaction in mechanistic detail. In this review, we summarize the current knowledge of host factors co-opted and signaling pathways activated during HCoV infection, with an emphasis on HCoV-infection-induced stress response, autophagy, apoptosis, and innate immunity. The cross talk among these pathways, as well as the modulatory strategies utilized by HCoV, is also discussed.
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Affiliation(s)
- To Sing Fung
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control and Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, Guangdong, People's Republic of China;
| | - Ding Xiang Liu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control and Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, Guangdong, People's Republic of China;
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25
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Abstract
RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G3BP/PABP-specific stress granules (SG) and GW182/DCP-specific RNA processing bodies (PB) are two major distinguishable RNA granules in somatic cells and contain various ribosomal subunits, translation factors, scaffold proteins, RNA-binding proteins, RNA decay enzymes and helicases to exclude mRNAs from the cellular active translational pool. Although SG formation is inducible due to cellular stress, PB exist physiologically in every cell. Both RNA granules are important components of the host antiviral defense. Virus infection imposes stress on host cells and thus induces SG formation. However, both RNA and DNA viruses must confront the hostile environment of host innate immunity and apply various strategies to block the formation of SG and PB for their effective infection and multiplication. This review summarizes the current research development in the field and the mechanisms of how individual viruses suppress the formation of host SG and PB for virus production.
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26
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Plazy C, Dumestre-Pérard C, Sarrot-Reynauld F, Audoin P, Quesada JL, Pierre P, Bouillet L, Cesbron JY, Clavarino G. Letter to the Editor: Protein phosphatase 1 subunit Ppp1r15a/GADD34 is overexpressed in systemic lupus erythematosus and related to the expression of type I interferon response genes. Autoimmun Rev 2018; 18:211-213. [PMID: 30578961 DOI: 10.1016/j.autrev.2018.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 09/30/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Caroline Plazy
- Laboratoire d'Immunologie, Pôle de Biologie, Centre Hospitalier Universitaire Grenoble Alpes, CS 10217, 38043 Grenoble, Cedex 9, France
| | - Chantal Dumestre-Pérard
- Laboratoire d'Immunologie, Pôle de Biologie, Centre Hospitalier Universitaire Grenoble Alpes, CS 10217, 38043 Grenoble, Cedex 9, France; BNI Team, TIMC-IMAG UMR5525, Université Grenoble Alpes, CNRS, BP170, 38042 Grenoble, Cedex 9, France
| | - Françoise Sarrot-Reynauld
- Clinique Universitaire de Médecine Interne, Pôle pluridisciplinaire de Médecine et de Gérontologie clinique, Grenoble University Hospital, CS 10217, 38043 Grenoble, France
| | - Pierre Audoin
- Direction de la Recherche Clinique et de l'Innovation, Pôle Recherche, Grenoble University Hospital, CS 10217, 38043 Grenoble, France
| | - Jean-Louis Quesada
- Direction de la Recherche Clinique et de l'Innovation, Pôle Recherche, Grenoble University Hospital, CS 10217, 38043 Grenoble, France
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm U1104, CNRS UMR7280, 13288 Marseille, France
| | - Laurence Bouillet
- Clinique Universitaire de Médecine Interne, Pôle pluridisciplinaire de Médecine et de Gérontologie clinique, Grenoble University Hospital, CS 10217, 38043 Grenoble, France
| | - Jean-Yves Cesbron
- Laboratoire d'Immunologie, Pôle de Biologie, Centre Hospitalier Universitaire Grenoble Alpes, CS 10217, 38043 Grenoble, Cedex 9, France; BNI Team, TIMC-IMAG UMR5525, Université Grenoble Alpes, CNRS, BP170, 38042 Grenoble, Cedex 9, France
| | - Giovanna Clavarino
- Laboratoire d'Immunologie, Pôle de Biologie, Centre Hospitalier Universitaire Grenoble Alpes, CS 10217, 38043 Grenoble, Cedex 9, France; BNI Team, TIMC-IMAG UMR5525, Université Grenoble Alpes, CNRS, BP170, 38042 Grenoble, Cedex 9, France.
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27
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Activation of the endoplasmic reticulum stress sensor IRE1α by the vaccine adjuvant AS03 contributes to its immunostimulatory properties. NPJ Vaccines 2018; 3:20. [PMID: 29977610 PMCID: PMC6023910 DOI: 10.1038/s41541-018-0058-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/24/2018] [Accepted: 05/01/2018] [Indexed: 01/31/2023] Open
Abstract
The oil-in-water emulsion Adjuvant System 03 (AS03) is one of the few adjuvants used in licensed vaccines. Previous work indicates that AS03 induces a local and transient inflammatory response that contributes to its adjuvant effect. However, the molecular mechanisms involved in its immunostimulatory properties are ill-defined. Upon intramuscular injection in mice, AS03 elicited a rapid and transient downregulation of lipid metabolism-related genes in the draining lymph node. In vitro, these modifications were associated with profound changes in lipid composition, alteration of endoplasmic reticulum (ER) morphology and activation of the unfolded protein response pathway. In vivo, treatment with a chemical chaperone or deletion of the ER stress sensor kinase IRE1α in myeloid cells decreased AS03-induced cytokine production and its capacity to elicit high affinity antigen-specific antibodies. In summary, our results indicate that IRE1α is a sensor for the metabolic changes induced by AS03 in monocytic cells and may constitute a canonical pathway that could be exploited for the design of novel vaccine adjuvants.
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28
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Battling for Ribosomes: Translational Control at the Forefront of the Antiviral Response. J Mol Biol 2018; 430:1965-1992. [PMID: 29746850 DOI: 10.1016/j.jmb.2018.04.040] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/24/2018] [Accepted: 04/27/2018] [Indexed: 01/05/2023]
Abstract
In the early stages of infection, gaining control of the cellular protein synthesis machinery including its ribosomes is the ultimate combat objective for a virus. To successfully replicate, viruses unequivocally need to usurp and redeploy this machinery for translation of their own mRNA. In response, the host triggers global shutdown of translation while paradoxically allowing swift synthesis of antiviral proteins as a strategy to limit collateral damage. This fundamental conflict at the level of translational control defines the outcome of infection. As part of this special issue on molecular mechanisms of early virus-host cell interactions, we review the current state of knowledge regarding translational control during viral infection with specific emphasis on protein kinase RNA-activated and mammalian target of rapamycin-mediated mechanisms. We also describe recent technological advances that will allow unprecedented insight into how viruses and host cells battle for ribosomes.
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29
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Smith JA. Regulation of Cytokine Production by the Unfolded Protein Response; Implications for Infection and Autoimmunity. Front Immunol 2018; 9:422. [PMID: 29556237 PMCID: PMC5844972 DOI: 10.3389/fimmu.2018.00422] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 02/16/2018] [Indexed: 12/14/2022] Open
Abstract
Protein folding in the endoplasmic reticulum (ER) is an essential cell function. To safeguard this process in the face of environmental threats and internal stressors, cells mount an evolutionarily conserved response known as the unfolded protein response (UPR). Invading pathogens induce cellular stress that impacts protein folding, thus the UPR is well situated to sense danger and contribute to immune responses. Cytokines (inflammatory cytokines and interferons) critically mediate host defense against pathogens, but when aberrantly produced, may also drive pathologic inflammation. The UPR influences cytokine production on multiple levels, from stimulation of pattern recognition receptors, to modulation of inflammatory signaling pathways, and the regulation of cytokine transcription factors. This review will focus on the mechanisms underlying cytokine regulation by the UPR, and the repercussions of this relationship for infection and autoimmune/autoinflammatory diseases. Interrogation of viral and bacterial infections has revealed increasing numbers of examples where pathogens induce or modulate the UPR and implicated UPR-modulated cytokines in host response. The flip side of this coin, the UPR/ER stress responses have been increasingly recognized in a variety of autoimmune and inflammatory diseases. Examples include monogenic disorders of ER function, diseases linked to misfolding protein (HLA-B27 and spondyloarthritis), diseases directly implicating UPR and autophagy genes (inflammatory bowel disease), and autoimmune diseases targeting highly secretory cells (e.g., diabetes). Given the burgeoning interest in pharmacologically targeting the UPR, greater discernment is needed regarding how the UPR regulates cytokine production during specific infections and autoimmune processes, and the relative place of this interaction in pathogenesis.
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Affiliation(s)
- Judith A Smith
- Department of Pediatrics, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States.,Department of Medical Microbiology and Immunology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
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Reverendo M, Mendes A, Argüello RJ, Gatti E, Pierre P. At the crossway of ER-stress and proinflammatory responses. FEBS J 2018; 286:297-310. [PMID: 29360216 DOI: 10.1111/febs.14391] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/12/2018] [Accepted: 01/18/2018] [Indexed: 12/13/2022]
Abstract
Immune cells detect specific microbes or damage to tissue integrity in order to initiate efficient immune responses. Abnormal accumulation of proteins in the endoplasmic reticulum (ER) can be seen as a sign of cellular malfunction and stress that triggers a collection of conserved emergency rescue programs. These different signaling cascades, which favor ER proteostasis and promote cell survival, are collectively known as the unfolded protein response (UPR). In recent years, a synergy between the UPR and inflammatory cytokine production has been unraveled, with different branches of the UPR entering in a cross-talk with specialized microbe sensing pathways, which turns on or amplify inflammatory cytokines production. Complementary to this synergetic activity, UPR induction alone, can itself be seen as a danger signal, and triggers directly or indirectly inflammation in different cellular and pathological models, this independently of the presence of pathogens. Here, we discuss recent advances on the nature of these cross-talks and how innate immunity, metabolism dysregulation, and ER-signaling pathways intersect in specialized immune cells, such as dendritic cells (DCs), and contribute to the pathogenesis of inflammatory diseases.
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Affiliation(s)
- Marisa Reverendo
- Aix Marseille Université, CNRS, INSERM, CIML, Marseille cedex 9, France.,International Associated Laboratory (LIA) CNRS 'Mistra', Marseille cedex 9, France
| | - Andreia Mendes
- Aix Marseille Université, CNRS, INSERM, CIML, Marseille cedex 9, France.,International Associated Laboratory (LIA) CNRS 'Mistra', Marseille cedex 9, France
| | - Rafael J Argüello
- Aix Marseille Université, CNRS, INSERM, CIML, Marseille cedex 9, France
| | - Evelina Gatti
- Aix Marseille Université, CNRS, INSERM, CIML, Marseille cedex 9, France.,International Associated Laboratory (LIA) CNRS 'Mistra', Marseille cedex 9, France.,Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, Portugal
| | - Philippe Pierre
- Aix Marseille Université, CNRS, INSERM, CIML, Marseille cedex 9, France.,International Associated Laboratory (LIA) CNRS 'Mistra', Marseille cedex 9, France.,Institute for Research in Biomedicine (iBiMED) and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, Portugal
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Perego J, Mendes A, Bourbon C, Camosseto V, Combes A, Liu H, Manh TPV, Dalet A, Chasson L, Spinelli L, Bardin N, Chiche L, Santos MAS, Gatti E, Pierre P. Guanabenz inhibits TLR9 signaling through a pathway that is independent of eIF2α dephosphorylation by the GADD34/PP1c complex. Sci Signal 2018; 11:11/514/eaam8104. [PMID: 29363586 DOI: 10.1126/scisignal.aam8104] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Endoplasmic reticulum (ER) stress triggers or amplifies inflammatory signals and cytokine production in immune cells. Upon the resolution of ER stress, the inducible phosphatase 1 cofactor GADD34 promotes the dephosphorylation of the initiation factor eIF2α, thereby enabling protein translation to resume. Several aminoguanidine compounds, such as guanabenz, perturb the eIF2α phosphorylation-dephosphorylation cycle and protect different cell or tissue types from protein misfolding and degeneration. We investigated how pharmacological interference with the eIF2α pathway could be beneficial to treat autoinflammatory diseases dependent on proinflammatory cytokines and type I interferons (IFNs), the production of which is regulated by GADD34 in dendritic cells (DCs). In mouse and human DCs and B cells, guanabenz prevented the activation of Toll-like receptor 9 (TLR9) by CpG oligodeoxynucleotides or DNA-immunoglobulin complexes in endosomes. In vivo, guanabenz protected mice from CpG oligonucleotide-dependent cytokine shock and decreased autoimmune symptom severity in a chemically induced model of systemic lupus erythematosus. However, we found that guanabenz exerted its inhibitory effect independently of GADD34 activity on eIF2α and instead decreased the abundance of CH25H, a cholesterol hydroxylase linked to antiviral immunity. Our results therefore suggest that guanabenz and similar compounds could be used to treat type I IFN-dependent pathologies and that CH25H could be a therapeutic target to control these diseases.
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Affiliation(s)
- Jessica Perego
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Andreia Mendes
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France.,International Associated Laboratory (LIA) CNRS "Mistra," 13008 Marseille, France
| | - Clarisse Bourbon
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Voahirana Camosseto
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France.,International Associated Laboratory (LIA) CNRS "Mistra," 13008 Marseille, France
| | - Alexis Combes
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Hong Liu
- Sanofi, Cambridge, MA 02139, USA
| | - Thien-Phong Vu Manh
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Alexandre Dalet
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Lionel Chasson
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Lionel Spinelli
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France
| | - Nathalie Bardin
- Laboratoire d'Immunologie, Hôpital de la Conception, 13005 Marseille, France.,Aix Marseille Université, INSERM, VRCM, 13005 Marseille, France
| | | | - Manuel A S Santos
- International Associated Laboratory (LIA) CNRS "Mistra," 13008 Marseille, France.,Institute for Research in Biomedicine (iBiMED) and Aveiro Health Sciences Program University of Aveiro, 3810-193 Aveiro, Portugal
| | - Evelina Gatti
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France. .,International Associated Laboratory (LIA) CNRS "Mistra," 13008 Marseille, France.,Institute for Research in Biomedicine (iBiMED) and Aveiro Health Sciences Program University of Aveiro, 3810-193 Aveiro, Portugal
| | - Philippe Pierre
- Aix Marseille Université, CNRS, INSERM, Centre d'Immunologie de Marseille-Luminy (CIML), 13008 Marseille, France. .,International Associated Laboratory (LIA) CNRS "Mistra," 13008 Marseille, France.,Institute for Research in Biomedicine (iBiMED) and Aveiro Health Sciences Program University of Aveiro, 3810-193 Aveiro, Portugal
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Abstract
Pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) are recognized by different cellular pathogen recognition receptors (PRRs), which are expressed on cell membrane or in the cytoplasm of cells of the innate immune system. Nucleic acids derived from pathogens or from certain cellular conditions represent a large category of PAMPs/DAMPs that trigger production of type I interferons (IFN-I) in addition to pro-inflammatory cytokines, by specifically binding to intracellular Toll-like receptors or cytosolic receptors. These cytosolic receptors, which are not related to TLRs and we call them “Toll-free” receptors, include the RNA-sensing RIG-I like receptors (RLRs), the DNA-sensing HIN200 family, and cGAS, amongst others. Viruses have evolved myriad strategies to evoke both host cellular and viral factors to evade IFN-I-mediated innate immune responses, to facilitate their infection, replication, and establishment of latency. This review outlines these “Toll-free” innate immune pathways and recent updates on their regulation, with focus on cellular and viral factors with enzyme activities.
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Affiliation(s)
- Ling Wang
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.,Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Shunbin Ning
- Department of Internal Medicine, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.,Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
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Highly Pathogenic New World Arenavirus Infection Activates the Pattern Recognition Receptor Protein Kinase R without Attenuating Virus Replication in Human Cells. J Virol 2017; 91:JVI.01090-17. [PMID: 28794024 DOI: 10.1128/jvi.01090-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/01/2017] [Indexed: 02/07/2023] Open
Abstract
The arenavirus family consists of several highly pathogenic viruses, including the Old World (OW) arenavirus Lassa fever virus (LASV) and the New World (NW) Junin virus (JUNV) and Machupo virus (MACV). Host response to infection by these pathogenic arenaviruses is distinct in many aspects. JUNV and MACV infections readily induce an interferon (IFN) response in human cells, while LASV infection usually triggers an undetectable or weak IFN response. JUNV induces an IFN response through RIG-I, suggesting that the host non-self RNA sensor readily detects JUNV viral RNAs (vRNAs) during infection and activates IFN response. Double-stranded-RNA (dsRNA)-activated protein kinase R (PKR) is another host non-self RNA sensor classically known for its vRNA recognition activity. Here we report that infection with NW arenaviruses JUNV and MACV, but not OW LASV, activated PKR, concomitant with elevated phosphorylation of the translation initiation factor α subunit of eukaryotic initiation factor 2 (eIF2α). Host protein synthesis was substantially suppressed in MACV- and JUNV-infected cells but was only marginally reduced in LASV-infected cells. Despite the antiviral activity known for PKR against many other viruses, the replication of JUNV and MACV was not impaired but was slightly augmented in wild-type (wt) cells compared to that in PKR-deficient cells, suggesting that PKR or PKR activation did not negatively affect JUNV and MACV infection. Additionally, we found an enhanced IFN response in JUNV- or MACV-infected PKR-deficient cells, which was inversely correlated with virus replication.IMPORTANCE The detection of viral RNA by host non-self RNA sensors, including RIG-I and MDA5, is critical to the initiation of the innate immune response to RNA virus infection. Among pathogenic arenaviruses, the OW LASV usually does not elicit an interferon response. However, the NW arenaviruses JUNV and MACV readily trigger an IFN response in a RIG-I-dependent manner. Here, we demonstrate for the first time that pathogenic NW arenaviruses JUNV and MACV, but not the OW arenavirus LASV, activated the dsRNA-dependent PKR, another host non-self RNA sensor, during infection. Interestingly, the replication of JUNV and MACV was not restricted but was rather slightly augmented in the presence of PKR. Our data provide new evidence for a distinct interplay between host non-self RNA sensors and pathogenic arenaviruses, which also provides insights into the pathogenesis of arenaviruses and may facilitate the design of vaccines and treatments against arenavirus-caused diseases.
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Abstract
Efficient viral gene expression is threatened by cellular stress response programmes that rapidly reprioritize the translation machinery in response to varied environmental assaults, including virus infection. This results in inhibition of bulk synthesis of housekeeping proteins and causes the aggregation of messenger ribonucleoprotein complexes into cytoplasmic foci that are known as stress granules, which can entrap viral mRNAs. There is accumulating evidence for the antiviral nature of stress granules, which is supported by the discovery of many viral factors that interfere with stress granule formation and/or function. This Review focuses on recent advances in our understanding of the role of translation inhibition and stress granules in antiviral immune responses.
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Perego J, Bourbon C, Chasson L, Laprie C, Spinelli L, Camosseto V, Gatti E, Pierre P. Guanabenz Prevents d-Galactosamine/Lipopolysaccharide-Induced Liver Damage and Mortality. Front Immunol 2017; 8:679. [PMID: 28659918 PMCID: PMC5468566 DOI: 10.3389/fimmu.2017.00679] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 05/24/2017] [Indexed: 12/19/2022] Open
Abstract
Multi-organ failure in response to uncontrolled microbial infection is characterized by low blood pressure accompanied by a systemic over-inflammation state, caused by massive pro-inflammatory cytokines release and liver damage. Recently, the integrated stress response (ISR), characterized by eukaryotic translation initiation factor 2α (eIF2α) phosphorylation, was involved with controlling apoptosis in stressed hepatocytes and associated with poor survival to endotoxin challenge. Lipopolysaccharide (LPS) alone is able to induce the ISR in hepatocytes and can trigger massive liver damage along with tumor necrosis factor-alpha (TNF-α) expression. Consequently, drugs interfering with eIF2α phosphorylation may represent potential candidates for the treatment of such pathologies. We, therefore, used Guanabenz (GBZ), a small compound with enhancing eIF2α phosphorylation activity to evaluate its effect on bacterial LPS sensing and endotoxemia. GBZ is confirmed here to have an anti-inflammatory activity by increasing in vitro interleukin-10 (IL-10) production by LPS-stimulated dendritic cells. We further show that in the d-galactosamine (d-galN)/LPS-dependent lethality model, intraperitoneal injection of GBZ promoted mice survival, prevented liver damage, increased IL-10 levels, and inhibited TNF-α production. GBZ and its derivatives could therefore represent an interesting pharmacological solution to control systemic inflammation and associated acute liver failure.
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Affiliation(s)
- Jessica Perego
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | | | - Lionel Chasson
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | - Caroline Laprie
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | - Lionel Spinelli
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | | | - Evelina Gatti
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France.,Aveiro Health Sciences Program, Institute for Research in Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA), CNRS "Mistra", Marseille, France
| | - Philippe Pierre
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France.,Aveiro Health Sciences Program, Institute for Research in Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA), CNRS "Mistra", Marseille, France
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36
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Zarcone MC, van Schadewijk A, Duistermaat E, Hiemstra PS, Kooter IM. Diesel exhaust alters the response of cultured primary bronchial epithelial cells from patients with chronic obstructive pulmonary disease (COPD) to non-typeable Haemophilus influenzae. Respir Res 2017; 18:27. [PMID: 28129777 PMCID: PMC5273858 DOI: 10.1186/s12931-017-0510-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 01/16/2017] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Exacerbations constitute a major cause of morbidity and mortality in patients suffering from chronic obstructive pulmonary disease (COPD). Both bacterial infections, such as those with non-typeable Haemophilus influenzae (NTHi), and exposures to diesel engine emissions are known to contribute to exacerbations in COPD patients. However, the effect of diesel exhaust (DE) exposure on the epithelial response to microbial stimulation is incompletely understood, and possible differences in the response to DE of epithelial cells from COPD patients and controls have not been studied. METHODS Primary bronchial epithelial cells (PBEC) were obtained from age-matched COPD patients (n = 7) and controls (n = 5). PBEC were cultured at the air-liquid interface (ALI) to achieve mucociliary differentiation. ALI-PBECs were apically exposed for 1 h to a stream of freshly generated whole DE or air. Exposure was followed by 3 h incubation in presence or absence of UV-inactivated NTHi before analysis of epithelial gene expression. RESULTS DE alone induced an increase in markers of oxidative stress (HMOX1, 50-100-fold) and of the integrated stress response (CHOP, 1.5-2-fold and GADD34, 1.5-fold) in cells from both COPD patients and controls. Exposure of COPD cultures to DE followed by NTHi caused an additive increase in GADD34 expression (up to 3-fold). Importantly, DE caused an inhibition of the NTHi-induced expression of the antimicrobial peptide S100A7, and of the chaperone protein HSP5A/BiP. CONCLUSIONS Our findings show that DE exposure of differentiated primary airway epithelial cells causes activation of the gene expression of HMOX1 and markers of integrated stress response to a similar extent in cells from COPD donors and controls. Furthermore, DE further increased the NTHi-induced expression of GADD34, indicating a possible enhancement of the integrated stress response. DE reduced the NTHi-induced expression of S100A7. These data suggest that DE exposure may cause adverse health effects in part by decreasing host defense against infection and by modulating stress responses.
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Affiliation(s)
- Maria C Zarcone
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands.
| | - Annemarie van Schadewijk
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | | | - Pieter S Hiemstra
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Ingeborg M Kooter
- Netherlands Organization for Applied Scientific Research, Utrecht, The Netherlands
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37
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Navid F, Colbert RA. Causes and consequences of endoplasmic reticulum stress in rheumatic disease. Nat Rev Rheumatol 2016; 13:25-40. [PMID: 27904144 DOI: 10.1038/nrrheum.2016.192] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rheumatic diseases represent a heterogeneous group of inflammatory conditions, many of which involve chronic activation of both innate and adaptive immune responses by multiple genetic and environmental factors. These immune responses involve the secretion of excessive amounts of cytokines and other signalling mediators by activated immune cells. The endoplasmic reticulum (ER) is the cellular organelle that directs the folding, processing and trafficking of membrane-bound and secreted proteins, including many key components of the immune response. Maintaining homeostasis in the ER is critical to cell function and survival. Consequently, elaborate mechanisms have evolved to sense and respond to ER stress through three main signalling pathways that together comprise the unfolded protein response (UPR). Activation of the UPR can rapidly resolve the accumulation of misfolded proteins, direct permanent changes in the size and function of cells during differentiation, and critically influence the immune response and inflammation. Recognition of the importance of ER stress and UPR signalling pathways in normal and dysregulated immune responses has greatly increased in the past few years. This Review discusses several settings in which ER stress contributes to the pathogenesis of rheumatic diseases and considers some of the therapeutic opportunities that these discoveries provide.
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Affiliation(s)
- Fatemeh Navid
- Pediatric Translational Research Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Building 10, Room 12N248B,10 Center Drive, Bethesda, Maryland 20892, USA
| | - Robert A Colbert
- Pediatric Translational Research Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Building 10, Room 12N248B,10 Center Drive, Bethesda, Maryland 20892, USA
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Abstract
In multicellular organisms, the epithelia is a contact surface with the surrounding environment and is exposed to a variety of adverse biotic (pathogenic) and abiotic (chemical) factors. Multi-layered pathways that operate on different time scales have evolved to preserve cellular integrity and elicit stress-specific response. Several stress-response programs are activated until a complete elimination of the stress is achieved. The innate immune response, which is triggered by pathogenic invasion, is rather harmful when active over a prolonged time, thus the response follows characteristic oscillatory trajectories. Here, we review different translation programs that function to precisely fine-tune the time at which various components of the innate immune response dwell between active and inactive. We discuss how different pro-inflammatory pathways are co-ordinated to temporally offset single reactions and to achieve an optimal balance between fighting pathogens and being less harmful for healthy cells.
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Wang L, Zhao J, Ren J, Hall KH, Moorman JP, Yao ZQ, Ning S. Protein phosphatase 1 abrogates IRF7-mediated type I IFN response in antiviral immunity. Eur J Immunol 2016; 46:2409-2419. [PMID: 27469204 DOI: 10.1002/eji.201646491] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 07/12/2016] [Accepted: 07/26/2016] [Indexed: 02/04/2023]
Abstract
Interferon (IFN) regulatory factor 7 (IRF7) plays a key role in the production of IFN-α in response to viral infection, and phosphorylation at IRF7 C-terminal serine sites is prelude to its function. However, phosphatases that negatively regulate IRF7 phosphorylation and activity have not been reported. In this study, we have identified a conserved protein phosphatase 1 (PP1)-binding motif in human and mouse IRF7 proteins, and shown that PP1 physically interacts with IRF7. Exogenous expression of PP1 subunits (PP1α, β, or γ) ablates IKKε-stimulated IRF7 phosphorylation and dramatically attenuates IRF7 transcriptional activity. Inhibition of PP1 activity significantly increases IRF7 phosphorylation and IRF7-mediated IFN-α production in response to Newcastle disease virus (NDV) infection or Toll-like receptor 7 (TLR7) challenge, leading to impaired viral replication. In addition, IFN treatment, TLR challenges and viral infection induce PP1 expression. Our findings disclose for the first time a pivotal role for PP1 in impeding IRF7-mediated IFN-α production in host immune responses.
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Affiliation(s)
- Ling Wang
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.,Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA
| | - Juan Zhao
- Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA
| | - Junping Ren
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.,Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA
| | - Kenton H Hall
- Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA
| | - Jonathan P Moorman
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.,Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA.,Hepatitis (HCV/HIV) Program, James H Quillen VA Medical Center, Johnson City, TN, USA
| | - Zhi Q Yao
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.,Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA.,Hepatitis (HCV/HIV) Program, James H Quillen VA Medical Center, Johnson City, TN, USA
| | - Shunbin Ning
- Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA. .,Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA.
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GADD34 suppresses lipopolysaccharide-induced sepsis and tissue injury through the regulation of macrophage activation. Cell Death Dis 2016; 7:e2219. [PMID: 27171261 PMCID: PMC4917654 DOI: 10.1038/cddis.2016.116] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/31/2016] [Accepted: 04/07/2016] [Indexed: 01/22/2023]
Abstract
Growth arrest and DNA damage inducible protein 34 (GADD34) is induced by various cellular stresses, such as DNA damage, endoplasmic reticulum stress, and amino-acid deprivation. Although the major roles of GADD34 are regulating ER stress responses and apoptosis, a recent study suggested that GADD34 is linked to innate immune responses. In this report, we investigated the roles of GADD34 in inflammatory responses against bacterial infection. To explore the effects of GADD34 on systemic inflammation in vivo, we employed a lipopolysaccharide (LPS)-induced murine sepsis model and assessed the lethality, serum cytokine levels, and tissue injury in the presence or absence of GADD34. We found that GADD34 deficiency increased the lethality and serum cytokine levels in LPS-induced sepsis. Moreover, GADD34 deficiency enhanced tissue destruction, cell death, and pro-inflammatory cytokine expression in LPS-induced acute liver injury. Pro-inflammatory cytokine production after LPS stimulation is regulated by the Toll-like receptor 4 (TLR4)-mediated NF-κB signaling pathway. In vitro experiments revealed that GADD34 suppressed pro-inflammatory cytokine production by macrophages through dephosphorylation of IKKβ. In conclusion, GADD34 attenuates LPS-induced sepsis and acute tissue injury through suppressing macrophage activation. Targeting this anti-inflammatory role of GADD34 may be a promising area for the development of therapeutic agents to regulate inflammatory disorders.
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Clavarino G, Adriouach S, Quesada JL, Clay M, Chevreau M, Trocmé C, Grange L, Gaudin P, Gatti E, Pierre P, Cesbron JY, Dumestre-Pérard C. Unfolded protein response gene GADD34 is overexpressed in rheumatoid arthritis and related to the presence of circulating anti-citrullinated protein antibodies. Autoimmunity 2016; 49:172-8. [DOI: 10.3109/08916934.2016.1138220] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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42
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Tanaka Y, Ito S, Oshino R, Chen N, Nishio N, Isobe KI. Effects of growth arrest and DNA damage-inducible protein 34 (GADD34) on inflammation-induced colon cancer in mice. Br J Cancer 2015. [PMID: 26196182 PMCID: PMC4647681 DOI: 10.1038/bjc.2015.263] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Background: Growth arrest and DNA damage-inducible protein 34 (GADD34/Ppp1r15a) is a family of GADD proteins that are induced by DNA damage. GADD34 protein has been suggested to regulate inflammation or host defense systems. However, the in vivo function of GADD34 in inflammation is still unclear. Long lasting inflammation, such as that seen in Crohn's disease and ulcerative colitis, is associated with a higher incidence of colorectal cancer (CRC). Methods: Using a colitis-associated cancer model, we analysed GADD34-deficient (KO) mice to study the effect of GADD34 on colitis and colorectal tumorigenesis. Results: We found a higher incidence of CRC in wild-type (WT) mice than in GADD34KO mice. Moreover, dextran sodium sulfate (DSS)-induced inflammatory responses were downregulated by GADD34 deficiency. The expression of pro-inflammatory mediators such as TNFα, IL-6, and iNOS/NOS2 was higher in the colons of WT mice than GADD34KO mice. IL-6 is known to activate STAT3 signalling in colonic epithelial cells and subsequently induced epithelial proliferation. We found that IL-6-STAT3 signalling and epithelial proliferation were higher in WT mice compared with GADD34KO mice. Conclusions: These results indicated that GADD34 upregulated pro-inflammatory mediator production leading to a higher tumour burden following azoxymethane (AOM)/DSS treatment.
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Affiliation(s)
- Yuriko Tanaka
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Sachiko Ito
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Reina Oshino
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Nana Chen
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Naomi Nishio
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Ken-ichi Isobe
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
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43
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van ‘t Wout EFA, van Schadewijk A, van Boxtel R, Dalton LE, Clarke HJ, Tommassen J, Marciniak SJ, Hiemstra PS. Virulence Factors of Pseudomonas aeruginosa Induce Both the Unfolded Protein and Integrated Stress Responses in Airway Epithelial Cells. PLoS Pathog 2015; 11:e1004946. [PMID: 26083346 PMCID: PMC4471080 DOI: 10.1371/journal.ppat.1004946] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 05/11/2015] [Indexed: 12/20/2022] Open
Abstract
Pseudomonas aeruginosa infection can be disastrous in chronic lung diseases such as cystic fibrosis and chronic obstructive pulmonary disease. Its toxic effects are largely mediated by secreted virulence factors including pyocyanin, elastase and alkaline protease (AprA). Efficient functioning of the endoplasmic reticulum (ER) is crucial for cell survival and appropriate immune responses, while an excess of unfolded proteins within the ER leads to “ER stress” and activation of the “unfolded protein response” (UPR). Bacterial infection and Toll-like receptor activation trigger the UPR most likely due to the increased demand for protein folding of inflammatory mediators. In this study, we show that cell-free conditioned medium of the PAO1 strain of P. aeruginosa, containing secreted virulence factors, induces ER stress in primary bronchial epithelial cells as evidenced by splicing of XBP1 mRNA and induction of CHOP, GRP78 and GADD34 expression. Most aspects of the ER stress response were dependent on TAK1 and p38 MAPK, except for the induction of GADD34 mRNA. Using various mutant strains and purified virulence factors, we identified pyocyanin and AprA as inducers of ER stress. However, the induction of GADD34 was mediated by an ER stress-independent integrated stress response (ISR) which was at least partly dependent on the iron-sensing eIF2α kinase HRI. Our data strongly suggest that this increased GADD34 expression served to protect against Pseudomonas-induced, iron-sensitive cell cytotoxicity. In summary, virulence factors from P. aeruginosa induce ER stress in airway epithelial cells and also trigger the ISR to improve cell survival of the host. Pseudomonas aeruginosa causes a devastating infection when it affects patients with cystic fibrosis or other chronic lung diseases. It often causes chronic infection due to its resistance to antibiotic treatment and its ability to form biofilms in these patients. The toxic effects of P. aeruginosa are largely mediated by secreted virulence factors. Efficient functioning of the endoplasmic reticulum is crucial for cell survival and appropriate immune responses, while its dysfunction causes stress and activation of the unfolded protein response. In this study, we found that virulence factors secreted by P. aeruginosa trigger the unfolded protein response in human cells by causing endoplasmic reticulum stress. In addition, secreted virulence factors activate the integrated stress response via a parallel independent pathway. Both stress pathways lead to the induction of the protein GADD34, which appears to provide protection against the toxic effects of the secreted virulence factors.
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Affiliation(s)
- Emily F. A. van ‘t Wout
- Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | | | - Ria van Boxtel
- Department of Molecular Microbiology, Utrecht University, Utrecht, the Netherlands
| | - Lucy E. Dalton
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Hanna J. Clarke
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Jan Tommassen
- Department of Molecular Microbiology, Utrecht University, Utrecht, the Netherlands
| | - Stefan J. Marciniak
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Pieter S. Hiemstra
- Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands
- * E-mail:
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44
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Chaudhary K, Shinde R, Liu H, Gnana-Prakasam JP, Veeranan-Karmegam R, Huang L, Ravishankar B, Bradley J, Kvirkvelia N, McMenamin M, Xiao W, Kleven D, Mellor AL, Madaio MP, McGaha TL. Amino acid metabolism inhibits antibody-driven kidney injury by inducing autophagy. THE JOURNAL OF IMMUNOLOGY 2015; 194:5713-24. [PMID: 25980011 DOI: 10.4049/jimmunol.1500277] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 04/17/2015] [Indexed: 11/19/2022]
Abstract
Inflammatory kidney disease is a major clinical problem that can result in end-stage renal failure. In this article, we show that Ab-mediated inflammatory kidney injury and renal disease in a mouse nephrotoxic serum nephritis model was inhibited by amino acid metabolism and a protective autophagic response. The metabolic signal was driven by IFN-γ-mediated induction of indoleamine 2,3-dioxygenase 1 (IDO1) enzyme activity with subsequent activation of a stress response dependent on the eIF2α kinase general control nonderepressible 2 (GCN2). Activation of GCN2 suppressed proinflammatory cytokine production in glomeruli and reduced macrophage recruitment to the kidney during the incipient stage of Ab-induced glomerular inflammation. Further, inhibition of autophagy or genetic ablation of Ido1 or Gcn2 converted Ab-induced, self-limiting nephritis to fatal end-stage renal disease. Conversely, increasing kidney IDO1 activity or treating mice with a GCN2 agonist induced autophagy and protected mice from nephritic kidney damage. Finally, kidney tissue from patients with Ab-driven nephropathy showed increased IDO1 abundance and stress gene expression. Thus, these findings support the hypothesis that the IDO-GCN2 pathway in glomerular stromal cells is a critical negative feedback mechanism that limits inflammatory renal pathologic changes by inducing autophagy.
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Affiliation(s)
- Kapil Chaudhary
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Rahul Shinde
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Haiyun Liu
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Jaya P Gnana-Prakasam
- Signaling and Angiogenesis Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | | | - Lei Huang
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912; Department of Radiology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Buvana Ravishankar
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Jillian Bradley
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Nino Kvirkvelia
- Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912; and
| | - Malgorzata McMenamin
- Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912; and
| | - Wei Xiao
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912
| | - Daniel Kleven
- Department of Pathology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Andrew L Mellor
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912; Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912; and
| | - Michael P Madaio
- Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912; and
| | - Tracy L McGaha
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Augusta, GA 30912; Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912; and
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45
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Dalet A, Gatti E, Pierre P. Integration of PKR-dependent translation inhibition with innate immunity is required for a coordinated anti-viral response. FEBS Lett 2015; 589:1539-45. [PMID: 25979169 DOI: 10.1016/j.febslet.2015.05.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 04/29/2015] [Accepted: 05/02/2015] [Indexed: 01/26/2023]
Abstract
Viral triggering of the innate immune response in infected cells aims at delaying viral replication and prevents tissue spreading. Viral replication is delayed by host protein synthesis inhibition and infected cell apoptosis on one hand, while infection spreading is controlled by the synthesis of specific proteins like type-I interferons (IFNs) and pro-inflammatory cytokines on the other hand. How do these two apparent conflicting responses cooperate within the same infected cells to mount effective defenses against pathogens? What are the molecules or the complexes resolving this contradiction over time? Some recent studies reveal unanticipated connections between innate immunity and stress pathways, giving important clues on how the cellular responses are orchestrated to limit infection efficiently.
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Affiliation(s)
- Alexandre Dalet
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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46
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Argüello RJ, Rodriguez Rodrigues C, Gatti E, Pierre P. Protein synthesis regulation, a pillar of strength for innate immunity? Curr Opin Immunol 2014; 32:28-35. [PMID: 25553394 DOI: 10.1016/j.coi.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
Recognition of pathogen derived molecules by Pattern Recognition Receptors (PRR) induces the production of cytokines (i.e. type I interferons) that stimulate the surrounding cells to transcribe and translate hundreds of genes, in order to prevent further infection and organize the immune response. Here, we report on the rising matter that metabolism sensing and gene expression control at the level of mRNA translation, allow swift responses that mobilize host defenses and coordinate innate responses to infection.
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Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Christian Rodriguez Rodrigues
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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47
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Fung TS, Huang M, Liu DX. Coronavirus-induced ER stress response and its involvement in regulation of coronavirus-host interactions. Virus Res 2014; 194:110-23. [PMID: 25304691 PMCID: PMC7114476 DOI: 10.1016/j.virusres.2014.09.016] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 09/25/2014] [Accepted: 09/28/2014] [Indexed: 12/11/2022]
Abstract
Coronavirus replication is structurally and functionally associated with the endoplasmic reticulum (ER), a major site of protein synthesis, folding, modification and sorting in the eukaryotic cells. Disturbance of ER homeostasis may occur under various physiological or pathological conditions. In response to the ER stress, signaling pathways of the unfolded protein response (UPR) are activated. UPR is mediated by three ER transmembrane sensors, namely the PKR-like ER protein kinase (PERK), the inositol-requiring protein 1 (IRE1) and the activating transcriptional factor 6 (ATF6). UPR facilitates adaptation to ER stress by reversible translation attenuation, enhancement of ER protein folding capacity and activation of ER-associated degradation (ERAD). In cells under prolonged and irremediable ER stress, UPR can also trigger apoptotic cell death. Accumulating evidence has shown that coronavirus infection causes ER stress and induces UPR in the infected cells. UPR is closely associated with a number of major signaling pathways, including autophagy, apoptosis, the mitogen-activated protein (MAP) kinase pathways, innate immunity and pro-inflammatory response. Therefore, studies on the UPR are pivotal in elucidating the complicated issue of coronavirus-host interaction. In this paper, we present the up-to-date knowledge on coronavirus-induced UPR and discuss its potential involvement in regulation of innate immunity and apoptosis.
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Affiliation(s)
- To Sing Fung
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Mei Huang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Ding Xiang Liu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
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48
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Wei N, Zhu LQ, Liu D. ATF4: a Novel Potential Therapeutic Target for Alzheimer's Disease. Mol Neurobiol 2014; 52:1765-1770. [PMID: 25381575 DOI: 10.1007/s12035-014-8970-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 10/28/2014] [Indexed: 12/27/2022]
Abstract
Activating transcription factor 4 (ATF4) belongs to the activating transcription factor family and its expression is increased upon the stimulation of a diverse array of microenvironmental stresses. ATF4 plays a major role in the development, metabolism, and memory formation. Alzheimer's disease (AD) is a prevalent neurodegenerative disease in aged population. The dominant pathological changes in AD brain, including the neurofibrillary tangles, consist of hyperphosphorylated tau protein, senile plaques composed of β-amyloid proteins, loss of neurons in the whole brain, and dysfunction of synapses. The protein level of ATF4 is upregulated in both AD brain and AD mouse model, indicating its latent roles in the pathogenesis of this disease. In this paper, we reviewed the related literatures about the interaction of ATF4 with the different types of pathological changes in AD brain and pointed out some unsolved problems in this area. We also proposed that a fine regulation of ATF4 in separate neurons or brain regions might be benefit to the therapy of AD.
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Affiliation(s)
- Na Wei
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
- Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Ling-Qiang Zhu
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
- Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Dan Liu
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
- Department of Medical Genetics, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
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49
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van 't Wout EFA, Hiemstra PS, Marciniak SJ. The integrated stress response in lung disease. Am J Respir Cell Mol Biol 2014; 50:1005-9. [PMID: 24605820 DOI: 10.1165/rcmb.2014-0019tr] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lungs are repeatedly exposed to inhaled toxic insults, such as smoke, diesel exhaust, and microbes, which elicit cellular stress responses. The phosphorylation of eukaryotic translation initiation factor 2α by one of four stress-sensing kinases triggers a pathway called the integrated stress response that helps protect cellular reserves of nutrients and prevents the accumulation of toxic proteins. In this review, we discuss how activation of the integrated stress response has been shown to play an important role in pulmonary pathology, and how its study may help in the development of novel therapies for diverse conditions, from hypoxia to cancer.
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Affiliation(s)
- Emily F A van 't Wout
- 1 Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands; and
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50
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25-Hydroxycholesterol acts as an amplifier of inflammatory signaling. Proc Natl Acad Sci U S A 2014; 111:10666-71. [PMID: 24994901 DOI: 10.1073/pnas.1404271111] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Cross-talk between sterol regulatory pathways and inflammatory pathways has been demonstrated to significantly impact the development of both atherosclerosis and infectious disease. The oxysterol 25-hydroxycholesterol (25HC) plays multiple roles in lipid biosynthesis and immunity. We recently used a systems biology approach to identify 25HC as an innate immune mediator that had a predicted role in atherosclerosis and we demonstrated a role for 25HC in foam cell formation. Here, we show that this mediator also has several complex roles in the antiviral response. The host response to viruses involves gene regulatory circuits with multiple feedback loops and we show here that 25HC acts as an amplifier of inflammatory signaling in macrophages. We determined that 25HC amplifies inflammatory signaling, at least in part, by mediating the recruitment of the AP-1 components FBJ osteosarcoma oncogene (FOS) and jun proto-oncogene (JUN) to the promoters of a subset of Toll-like receptor-responsive genes. Consistent with previous reports, we found that 25HC inhibits in vitro infection of airway epithelial cells by influenza. Surprisingly, we found that deletion of Ch25h, the gene encoding the enzyme responsible for 25HC production, is protective in a mouse model of influenza infection as a result of decreased inflammatory-induced pathology. Thus, our study demonstrates, for the first time to our knowledge, that in addition to its direct antiviral role, 25HC also regulates transcriptional responses and acts as an amplifier of inflammation via AP-1 and that the resulting alteration in inflammatory response leads to increased tissue damage in mice following infection with influenza.
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