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Chen Y, Jiang X, Yuan Y, Chen Y, Wei S, Yu Y, Zhou Q, Yu Y, Wang J, Liu H, Hua X, Yang Z, Chen Z, Li Y, Wang Q, Chen J, Wang Y. Coptisine inhibits neointimal hyperplasia through attenuating Pak1/Pak2 signaling in vascular smooth muscle cells without retardation of re-endothelialization. Atherosclerosis 2024; 391:117480. [PMID: 38447436 DOI: 10.1016/j.atherosclerosis.2024.117480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 02/04/2024] [Accepted: 02/08/2024] [Indexed: 03/08/2024]
Abstract
BACKGROUND AND AIMS Vascular injury-induced endothelium-denudation and profound vascular smooth muscle cells (VSMCs) proliferation and dis-regulated apoptosis lead to post-angioplasty restenosis. Coptisine (CTS), an isoquinoline alkaloid, has multiple beneficial effects on the cardiovascular system. Recent studies identified it selectively inhibits VSMCs proliferation. However, its effects on neointimal hyperplasia, re-endothelialization, and the underlying mechanisms are still unclear. METHODS Cell viability was assayed by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and cell counting kit-8 (CCK-8). Cell proliferation and apoptosis were measured by flow cytometry and immunofluorescence of Ki67 and TUNEL. Quantitative phosphoproteomics (QPP) was employed to screen CTS-responsive phosphor-sites in the key regulators of cell proliferation and apoptosis. Neointimal hyperplasia was induced by balloon injury of rat left carotid artery (LCA). Adenoviral gene transfer was conducted in both cultured cells and LCA. Re-endothelialization was evaluated by Evan's blue staining of LCA. RESULTS 1) CTS had strong anti-proliferative and pro-apoptotic effects in cultured rat VSMCs, with the EC50 4∼10-folds lower than that in endothelial cells (ECs). 2) Rats administered with CTS, either locally to LCA's periadventitial space or orally, demonstrated a potently inhibited balloon injury-induced neointimal hyperplasia, but had no delaying effect on re-endothelialization. 3) The QPP results revealed that the phosphorylation levels of Pak1S144/S203, Pak2S20/S197, Erk1T202/Y204, Erk2T185/Y187, and BadS136 were significantly decreased in VSMCs by CTS. 4) Adenoviral expression of phosphomimetic mutants Pak1D144/D203/Pak2D20/D197 enhanced Pak1/2 activities, stimulated the downstream pErk1T202/Y204/pErk2T185/Y187/pErk3S189/pBadS136, attenuated CTS-mediated inhibition of VSMCs proliferation and promotion of apoptosis in vitro, and potentiated neointimal hyperplasia in vivo. 5) Adenoviral expression of phosphoresistant mutants Pak1A144/A203/Pak2A20/A197 inactivated Pak1/2 and totally simulated the inhibitory effects of CTS on platelet-derived growth factor (PDGF)-stimulated VSMCs proliferation and PDGF-inhibited apoptosis in vitro and neointimal hyperplasia in vivo. 6) LCA injury significantly enhanced the endogenous phosphorylation levels of all but pBadS136. CTS markedly attenuated all the enhanced levels. CONCLUSIONS These results indicate that CTS is a promising medicine for prevention of post-angioplasty restenosis without adverse impact on re-endothelialization. CTS-directed suppression of pPak1S144/S203/pPak2S20/S197 and the subsequent effects on downstream pErk1T202/Y204/pErk2T185/Y187/pErk3S189 and pBadS136 underline its mechanisms of inhibition of VSMCs proliferation and stimulation of apoptosis. Therefore, the phosphor-sites of Pak1S144/S203/Pak2S20/S197 constitute a potential drug-screening target for fighting neointimal hyperplasia restenosis.
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Affiliation(s)
- Yuhan Chen
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Xueze Jiang
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China; Department of Cardiology, Baoshan Branch of Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200444, China
| | - Yuchan Yuan
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Yuanyuan Chen
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Sisi Wei
- Children Inherited Metabolism and Endocrine Department, Guangdong Women and Children Hospital, Panyu District, Guangzhou, Guangdong, 511400, China
| | - Ying Yu
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Qing Zhou
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Yi Yu
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Julie Wang
- Department of Computer Science, Brown University, Providence, RI, 02912, USA
| | - Hua Liu
- Department of Intensive Care Med, Zhongshan Hospital of Fudan University, Shanghai, 200032, China
| | - Xuesheng Hua
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Zhenwei Yang
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Zhiyong Chen
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Yigang Li
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China
| | - Qunshan Wang
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China.
| | - Jie Chen
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China.
| | - Yuepeng Wang
- Molecular Cardiology Research Laboratory, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200092, China.
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Su T, He Y, Huang Y, Ye M, Guo Q, Xiao Y, Cai G, Chen L, Li C, Zhou H, Luo X. Myeloid-derived grancalcin instigates obesity-induced insulin resistance and metabolic inflammation in male mice. Nat Commun 2024; 15:97. [PMID: 38167327 PMCID: PMC10762069 DOI: 10.1038/s41467-023-43787-x] [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: 11/09/2022] [Accepted: 11/20/2023] [Indexed: 01/05/2024] Open
Abstract
The crosstalk between the bone and adipose tissue is known to orchestrate metabolic homeostasis, but the underlying mechanisms are largely unknown. Herein, we find that GCA + (grancalcin) immune cells accumulate in the bone marrow and release a considerable amount of GCA into circulation during obesity. Genetic deletion of Gca in myeloid cells attenuates metabolic dysfunction in obese male mice, whereas injection of recombinant GCA into male mice causes adipose tissue inflammation and insulin resistance. Mechanistically, we found that GCA binds to the Prohibitin-2 (PHB2) receptor on adipocytes and activates the innate and adaptive immune response of adipocytes via the PAK1-NF-κB signaling pathway, thus provoking the infiltration of inflammatory immune cells. Moreover, we show that GCA-neutralizing antibodies improve adipose tissue inflammation and insulin sensitivity in obese male mice. Together, these observations define a mechanism whereby bone marrow factor GCA initiates adipose tissue inflammation and insulin resistance, showing that GCA could be a potential target to treat metainflammation.
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Affiliation(s)
- Tian Su
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Yue He
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Yan Huang
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Mingsheng Ye
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Qi Guo
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Ye Xiao
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Guangping Cai
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Linyun Chen
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Changjun Li
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Haiyan Zhou
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China.
| | - Xianghang Luo
- Endocrinology Research Center, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, 410008, China.
- Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, Hunan, 410008, China.
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3
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Worley MJ. Salmonella Bloodstream Infections. Trop Med Infect Dis 2023; 8:487. [PMID: 37999606 PMCID: PMC10675298 DOI: 10.3390/tropicalmed8110487] [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: 09/19/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 11/25/2023] Open
Abstract
Salmonella is a major foodborne pathogen of both animals and humans. This bacterium is responsible for considerable morbidity and mortality world-wide. Different serovars of this genus cause diseases ranging from self-limiting gastroenteritis to a potentially fatal systemic disease known as enteric fever. Gastrointestinal infections with Salmonella are usually self-limiting and rarely require medical intervention. Bloodstream infections, on the other hand, are often fatal even with hospitalization. This review describes the routes and underlying mechanisms of the extraintestinal dissemination of Salmonella and the chronic infections that sometimes result. It includes information on the pathogenicity islands and individual virulence factors involved in systemic dissemination as well as a discussion of the host factors that mediate susceptibility. Also, the major outbreaks of invasive Salmonella disease in the tropics are described.
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Affiliation(s)
- Micah J Worley
- Department of Biology, University of Louisville, Louisville, KY 40292, USA
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4
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Wang DN, Ni JJ, Li JH, Gao YQ, Ni FJ, Zhang ZZ, Fang JY, Lu J, Yao YF. Bacterial infection promotes tumorigenesis of colorectal cancer via regulating CDC42 acetylation. PLoS Pathog 2023; 19:e1011189. [PMID: 36812247 PMCID: PMC9987831 DOI: 10.1371/journal.ppat.1011189] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 03/06/2023] [Accepted: 02/07/2023] [Indexed: 02/24/2023] Open
Abstract
Increasing evidence highlights the role of bacteria in promoting tumorigenesis. The underlying mechanisms may be diverse and remain poorly understood. Here, we report that Salmonella infection leads to extensive de/acetylation changes in host cell proteins. The acetylation of mammalian cell division cycle 42 (CDC42), a member of the Rho family of GTPases involved in many crucial signaling pathways in cancer cells, is drastically reduced after bacterial infection. CDC42 is deacetylated by SIRT2 and acetylated by p300/CBP. Non-acetylated CDC42 at lysine 153 shows an impaired binding of its downstream effector PAK4 and an attenuated phosphorylation of p38 and JNK, consequently reduces cell apoptosis. The reduction in K153 acetylation also enhances the migration and invasion ability of colon cancer cells. The low level of K153 acetylation in patients with colorectal cancer (CRC) predicts a poor prognosis. Taken together, our findings suggest a new mechanism of bacterial infection-induced promotion of colorectal tumorigenesis by modulation of the CDC42-PAK axis through manipulation of CDC42 acetylation.
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Affiliation(s)
- Dan-Ni Wang
- Laboratory of Bacterial Pathogenesis, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jin-Jing Ni
- Laboratory of Bacterial Pathogenesis, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian-Hui Li
- Laboratory of Bacterial Pathogenesis, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Phage, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Ya-Qi Gao
- State Key Laboratory for Oncogenes and Related Genes; Division of Gastroenterology and Hepatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fang-Jing Ni
- Laboratory of Bacterial Pathogenesis, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhen-Zhen Zhang
- Department of Pathology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing-Yuan Fang
- State Key Laboratory for Oncogenes and Related Genes; Division of Gastroenterology and Hepatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jie Lu
- Department of Infectious Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- * E-mail: (JL); (Y-FY)
| | - Yu-Feng Yao
- Laboratory of Bacterial Pathogenesis, Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Infectious Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
- * E-mail: (JL); (Y-FY)
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5
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Abstract
The major function of the mammalian immune system is to prevent and control infections caused by enteropathogens that collectively have altered human destiny. In fact, as the gastrointestinal tissues are the major interface of mammals with the environment, up to 70% of the human immune system is dedicated to patrolling them The defenses are multi-tiered and include the endogenous microflora that mediate colonization resistance as well as physical barriers intended to compartmentalize infections. The gastrointestinal tract and associated lymphoid tissue are also protected by sophisticated interleaved arrays of active innate and adaptive immune defenses. Remarkably, some bacterial enteropathogens have acquired an arsenal of virulence factors with which they neutralize all these formidable barriers to infection, causing disease ranging from mild self-limiting gastroenteritis to in some cases devastating human disease.
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Affiliation(s)
- Micah J. Worley
- Department of Biology, University of Louisville, Louisville, Kentucky, USA,CONTACT Micah J. Worley Department of Biology, University of Louisville, 139 Life Sciences Bldg, Louisville, Kentucky, USA
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6
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Baumgartner M, Zirnbauer R, Schlager S, Mertens D, Gasche N, Sladek B, Herbold C, Bochkareva O, Emelianenko V, Vogelsang H, Lang M, Klotz A, Moik B, Makristathis A, Berry D, Dabsch S, Khare V, Gasche C. Atypical enteropathogenic E. coli are associated with disease activity in ulcerative colitis. Gut Microbes 2022; 14:2143218. [PMID: 36415023 PMCID: PMC9704410 DOI: 10.1080/19490976.2022.2143218] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
With increasing urbanization and industrialization, the prevalence of inflammatory bowel diseases (IBDs) has steadily been rising over the past two decades. IBD involves flares of gastrointestinal (GI) inflammation accompanied by microbiota perturbations. However, microbial mechanisms that trigger such flares remain elusive. Here, we analyzed the association of the emerging pathogen atypical enteropathogenic E. coli (aEPEC) with IBD disease activity. The presence of diarrheagenic E. coli was assessed in stool samples from 630 IBD patients and 234 age- and sex-matched controls without GI symptoms. Microbiota was analyzed with 16S ribosomal RNA gene amplicon sequencing, and 57 clinical aEPEC isolates were subjected to whole-genome sequencing and in vitro pathogenicity experiments including biofilm formation, epithelial barrier function and the ability to induce pro-inflammatory signaling. The presence of aEPEC correlated with laboratory, clinical and endoscopic disease activity in ulcerative colitis (UC), as well as microbiota dysbiosis. In vitro, aEPEC strains induce epithelial p21-activated kinases, disrupt the epithelial barrier and display potent biofilm formation. The effector proteins espV and espG2 distinguish aEPEC cultured from UC and Crohn's disease patients, respectively. EspV-positive aEPEC harbor more virulence factors and have a higher pro-inflammatory potential, which is counteracted by 5-ASA. aEPEC may tip a fragile immune-microbiota homeostasis and thereby contribute to flares in UC. aEPEC isolates from UC patients display properties to disrupt the epithelial barrier and to induce pro-inflammatory signaling in vitro.
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Affiliation(s)
- Maximilian Baumgartner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Rebecca Zirnbauer
- Division of Visceral Surgery, Department of General Surgery, Medical University of Vienna, Vienna, Austria
| | - Sabine Schlager
- National Reference Laboratory for Escherichia coli, Austrian Agency for Health and Food Safety, Graz, Austria
| | - Daniel Mertens
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | | | | | - Craig Herbold
- Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria
| | - Olga Bochkareva
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Vera Emelianenko
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Harald Vogelsang
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Michaela Lang
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria,Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria
| | - Anton Klotz
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Birgit Moik
- National Reference Laboratory for Escherichia coli, Austrian Agency for Health and Food Safety, Graz, Austria
| | - Athanasios Makristathis
- Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria,Division of Microbiology, Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - David Berry
- Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria,Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria
| | - Stefanie Dabsch
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Vineeta Khare
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria
| | - Christoph Gasche
- Division of Gastroenterology and Hepatology, Department of Internal Medicine 3, Medical University of Vienna, Vienna, Austria,CONTACT Christoph Gasche Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, Vienna, A-1090Austria
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7
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Guo P, Liu Y, Feng J, Tang S, Wei F, Feng J. p21-activated kinase 1 (PAK1) as a therapeutic target for cardiotoxicity. Arch Toxicol 2022; 96:3143-3162. [DOI: 10.1007/s00204-022-03384-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/14/2022] [Indexed: 11/02/2022]
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8
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Li Y, Yang L, Hu F, Xu J, Ye J, Liu S, Wang L, Zhuo M, Ran B, Zhang H, Ye J, Xiao J. Novel Thermosensitive Hydrogel Promotes Spinal Cord Repair by Regulating Mitochondrial Function. ACS APPLIED MATERIALS & INTERFACES 2022; 14:25155-25172. [PMID: 35618676 DOI: 10.1021/acsami.2c04341] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The repair of spinal cord injury (SCI) is still a tough clinical challenge and needs innovative therapies. Mitochondrial function is significantly compromised after SCI and has emerged as an important factor causing neuronal apoptosis and hindering functional recovery. In this study, umbilical cord mesenchymal stem cells (UCMSC), which are promising seed cells for nerve regeneration, and basic fibroblast growth factor (bFGF) that have been demonstrated to have a variety of effects on neural regeneration were jointly immobilized in extracellular matrix (ECM) and heparin-poloxamer (HP) to create a polymer bioactive system that brings more hope and possibility for the treatment of SCI. Our results in vitro and in vivo showed that the UCMSC-bFGF-ECM-HP thermosensitive hydrogel has good therapeutic effects, mainly in reducing apoptosis and improving the mitochondrial function. It showed promising utility for the functional recovery of impaired mitochondrial function by promoting mitochondrial fusion, reducing pathological mitochondrial fragmentation, increasing mitochondrial energy supply, and improving the metabolism of MDA, LDH, and ROS. In addition, we uncovered a distinct molecular mechanism underlying the protective effects associated with activating p21-activated kinase 1 (PAK1) and mitochondrial sirtuin 4 (SIRT4) by the UCMSC-bFGF-ECM-HP hydrogel. The expansion of new insights into the molecular relationships between PAK1 and SIRT4, which links the mitochondrial function in SCI, can lay the foundation for future applications and help to provide promising interventions of stem-cell-based biological scaffold therapies and potential therapeutic targets for the clinical formulation of SCI treatment strategies.
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Affiliation(s)
- Yi Li
- Medical College of Soochow University, Suzhou, Jiangsu 215123, China
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Liangliang Yang
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Fei Hu
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Ji Xu
- Department of Emergency, The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Junsong Ye
- Subcenter for Stem Cell Clinical Translation, The First Affiliated Hospital of Gannan Medical University, Ganzhou, Jiangxi 341000, China
- Ganzhou Key Laboratory of Stem Cell and Regenerative Medicine, Gannan Medical University, Ganzhou, Jiangxi 341000, China
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, Ganzhou, Jiangxi 341000, China
- Key Laboratory of Biomaterials and Biofabrication in Tissue Engineering of Jiangxi Province, Gannan Medical University, Ganzhou, Jiangxi 341000, China
| | - Shuhua Liu
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Lifeng Wang
- Medical College of Soochow University, Suzhou, Jiangsu 215123, China
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Ming Zhuo
- Medical College of Soochow University, Suzhou, Jiangsu 215123, China
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Bing Ran
- Medical College of Soochow University, Suzhou, Jiangsu 215123, China
- Department of Pain, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Hongyu Zhang
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Junming Ye
- Medical College of Soochow University, Suzhou, Jiangsu 215123, China
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical College, Ganzhou, Jiangxi 341000, China
| | - Jian Xiao
- School of Pharmaceutical Sciences, Cixi Biomedical Research Institute, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
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9
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Chang SJ, Hsu YT, Chen Y, Lin YY, Lara-Tejero M, Galan JE. Typhoid toxin sorting and exocytic transport from Salmonella Typhi-infected cells. eLife 2022; 11:e78561. [PMID: 35579416 PMCID: PMC9142146 DOI: 10.7554/elife.78561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/15/2022] [Indexed: 11/13/2022] Open
Abstract
Typhoid toxin is an essential virulence factor for Salmonella Typhi, the cause of typhoid fever in humans. This toxin has an unusual biology in that it is produced by Salmonella Typhi only when located within host cells. Once synthesized, the toxin is secreted to the lumen of the Salmonella-containing vacuole from where it is transported to the extracellular space by vesicle carrier intermediates. Here, we report the identification of the typhoid toxin sorting receptor and components of the cellular machinery that packages the toxin into vesicle carriers, and exports it to the extracellular space. We found that the cation-independent mannose-6-phosphate receptor serves as typhoid toxin sorting receptor and that the coat protein COPII and the GTPase Sar1 mediate its packaging into vesicle carriers. Formation of the typhoid toxin carriers requires the specific environment of the Salmonella Typhi-containing vacuole, which is determined by the activities of specific effectors of its type III protein secretion systems. We also found that Rab11B and its interacting protein Rip11 control the intracellular transport of the typhoid toxin carriers, and the SNARE proteins VAMP7, SNAP23, and Syntaxin 4 their fusion to the plasma membrane. Typhoid toxin's cooption of specific cellular machinery for its transport to the extracellular space illustrates the remarkable adaptation of an exotoxin to exert its function in the context of an intracellular pathogen.
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Affiliation(s)
- Shu-Jung Chang
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
- Graduate Institute of Microbiology, College of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Yu-Ting Hsu
- Graduate Institute of Microbiology, College of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Yun Chen
- Graduate Institute of Microbiology, College of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Yen-Yi Lin
- Graduate Institute of Microbiology, College of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Maria Lara-Tejero
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
| | - Jorge E Galan
- Department of Microbial Pathogenesis, Yale University School of MedicineNew HavenUnited States
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Salmonella Typhimurium and inflammation: a pathogen-centric affair. Nat Rev Microbiol 2021; 19:716-725. [PMID: 34012042 PMCID: PMC9350856 DOI: 10.1038/s41579-021-00561-4] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2021] [Indexed: 02/06/2023]
Abstract
Microbial infections are controlled by host inflammatory responses that are initiated by innate immune receptors after recognition of conserved microbial products. As inflammation can also lead to disease, tissues that are exposed to microbial products such as the intestinal epithelium are subject to stringent regulatory mechanisms to prevent indiscriminate signalling through innate immune receptors. The enteric pathogen Salmonella enterica subsp. enterica serovar Typhimurium, which requires intestinal inflammation to sustain its replication in the intestinal tract, uses effector proteins of its type III secretion systems to trigger an inflammatory response without the engagement of innate immune receptors. Furthermore, S. Typhimurium uses a different set of effectors to restrict the inflammatory response to preserve host homeostasis. The S. Typhimurium-host interface is a remarkable example of the unique balance that emerges from the co-evolution of a pathogen and its host.
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11
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Fattinger SA, Sellin ME, Hardt WD. Salmonella effector driven invasion of the gut epithelium: breaking in and setting the house on fire. Curr Opin Microbiol 2021; 64:9-18. [PMID: 34492596 DOI: 10.1016/j.mib.2021.08.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/10/2021] [Accepted: 08/17/2021] [Indexed: 12/15/2022]
Abstract
Salmonella Typhimurium (S.Tm) is a major cause of diarrheal disease. The invasion into intestinal epithelial cells (IECs) is a central step in the infection cycle. It is associated with gut inflammation and thought to benefit S.Tm proliferation also in the intestinal lumen. Importantly, it is still not entirely clear how inflammation is elicited and to which extent it links to IEC invasion efficiency in vivo. In this review, we summarize recent findings explaining IEC invasion by type-three-secretion-system-1 (TTSS-1) effector proteins and discuss their effects on invasion and gut inflammation. In non-polarized tissue culture cells, the TTSS-1 effectors (mainly SopB/E/E2) elicit large membrane ruffles fueling cooperative invasion, and can directly trigger pro-inflammatory signaling. By contrast, in the murine gut, we observe discreet-invasion (mainly via the TTSS-1 effector SipA) and a prominent pro-inflammatory role of the host?"s epithelial inflammasome(s), which sense pathogen associated molecular patterns (PAMPs). We discuss why it has remained a major challenge to tease apart direct and indirect inflammatory effects of TTSS-1 effectors and explain why further research will be needed to fully determine their inflammation-modulating role(s).
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Affiliation(s)
- Stefan A Fattinger
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland; Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
| | - Mikael E Sellin
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, Zurich, Switzerland.
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12
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Davidson A, Tyler J, Hume P, Singh V, Koronakis V. A kinase-independent function of PAK is crucial for pathogen-mediated actin remodelling. PLoS Pathog 2021; 17:e1009902. [PMID: 34460869 PMCID: PMC8432889 DOI: 10.1371/journal.ppat.1009902] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 09/10/2021] [Accepted: 08/17/2021] [Indexed: 02/02/2023] Open
Abstract
The p21-activated kinase (PAK) family regulate a multitude of cellular processes, including actin cytoskeleton remodelling. Numerous bacterial pathogens usurp host signalling pathways that regulate actin reorganisation in order to promote Infection. Salmonella and pathogenic Escherichia coli drive actin-dependent forced uptake and intimate attachment respectively. We demonstrate that the pathogen-driven generation of both these distinct actin structures relies on the recruitment and activation of PAK. We show that the PAK kinase domain is dispensable for this actin remodelling, which instead requires the GTPase-binding CRIB and the central poly-proline rich region. PAK interacts with and inhibits the guanine nucleotide exchange factor β-PIX, preventing it from exerting a negative effect on cytoskeleton reorganisation. This kinase-independent function of PAK may be usurped by other pathogens that modify host cytoskeleton signalling and helps us better understand how PAK functions in normal and diseased eukaryotic cells.
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Affiliation(s)
- Anthony Davidson
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Joe Tyler
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Peter Hume
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Vikash Singh
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Vassilis Koronakis
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
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13
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ARHGEF26 enhances Salmonella invasion and inflammation in cells and mice. PLoS Pathog 2021; 17:e1009713. [PMID: 34242364 PMCID: PMC8294491 DOI: 10.1371/journal.ppat.1009713] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/21/2021] [Accepted: 06/14/2021] [Indexed: 11/25/2022] Open
Abstract
Salmonella hijack host machinery in order to invade cells and establish infection. While considerable work has described the role of host proteins in invasion, much less is known regarding how natural variation in these invasion-associated host proteins affects Salmonella pathogenesis. Here we leveraged a candidate cellular GWAS screen to identify natural genetic variation in the ARHGEF26 (Rho Guanine Nucleotide Exchange Factor 26) gene that renders lymphoblastoid cells susceptible to Salmonella Typhi and Typhimurium invasion. Experimental follow-up redefined ARHGEF26’s role in Salmonella epithelial cell infection. Specifically, we identified complex serovar-by-host interactions whereby ARHGEF26 stimulation of S. Typhi and S. Typhimurium invasion into host cells varied in magnitude and effector-dependence based on host cell type. While ARHGEF26 regulated SopB- and SopE-mediated S. Typhi (but not S. Typhimurium) infection of HeLa cells, the largest effect of ARHGEF26 was observed with S. Typhimurium in polarized MDCK cells through a SopB- and SopE2-independent mechanism. In both cell types, knockdown of the ARHGEF26-associated protein DLG1 resulted in a similar phenotype and serovar specificity. Importantly, we show that ARHGEF26 plays a critical role in S. Typhimurium pathogenesis by contributing to bacterial burden in the enteric fever murine model, as well as inflammation in the colitis infection model. In the enteric fever model, SopB and SopE2 are required for the effects of Arhgef26 deletion on bacterial burden, and the impact of sopB and sopE2 deletion in turn required ARHGEF26. In contrast, SopB and SopE2 were not required for the impacts of Arhgef26 deletion on colitis. A role for ARHGEF26 on inflammation was also seen in cells, as knockdown reduced IL-8 production in HeLa cells. Together, these data reveal pleiotropic roles for ARHGEF26 during infection and highlight that many of the interactions that occur during infection that are thought to be well understood likely have underappreciated complexity. During infection, Salmonella manipulates host cells into engulfing the bacteria and establishing an intracellular niche. While many studies have identified genes involved in different stages of this Salmonella invasion process, few studies have examined how differences between human hosts contribute to infection susceptibility. Here we leveraged a candidate genetic screen to identify natural genetic variation in the human ARHGEF26 gene that correlates with Salmonella invasion. Springboarding from this result, we experimentally tested and redefined ARHGEF26’s role in Salmonella invasion, discovered a new role for ARHGEF26 in regulating inflammation during Salmonella disease, and demonstrated the relevance of these findings in mouse models. Building on how ARHGEF26 functions in other contexts, we implicated two ARHGEF26-interacting host proteins as contributors to Salmonella pathobiology. Collectively, these results identify a potential source of inter-person diversity in susceptibility to Salmonella disease and expand our molecular understanding of Salmonella infection to include a multifaceted role for ARHGEF26. They further identify important future directions in understanding how Salmonella recruit and manipulate ARHGEF26 as well as how ARHGEF26 is able to drive Salmonella-beneficial processes.
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14
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An unconventional role of an ASB family protein in NF-κB activation and inflammatory response during microbial infection and colitis. Proc Natl Acad Sci U S A 2021; 118:2015416118. [PMID: 33431678 DOI: 10.1073/pnas.2015416118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Nuclear factor κB (NF-κB)-mediated signaling pathway plays a crucial role in the regulation of inflammatory process, innate and adaptive immune responses. The hyperactivation of inflammatory response causes host cell death, tissue damage, and autoinflammatory disorders, such as sepsis and inflammatory bowel disease. However, how these processes are precisely controlled is still poorly understood. In this study, we demonstrated that ankyrin repeat and suppressor of cytokine signaling box containing 1 (ASB1) is involved in the positive regulation of inflammatory responses by enhancing the stability of TAB2 and its downstream signaling pathways, including NF-κB and mitogen-activated protein kinase pathways. Mechanistically, unlike other members of the ASB family that induce ubiquitination-mediated degradation of their target proteins, ASB1 associates with TAB2 to inhibit K48-linked polyubiquitination and thereby promote the stability of TAB2 upon stimulation of cytokines and lipopolysaccharide (LPS), which indicates that ASB1 plays a noncanonical role to further stabilize the target protein rather than induce its degradation. The deficiency of Asb1 protects mice from Salmonella typhimurium- or LPS-induced septic shock and increases the survival of mice. Moreover, Asb1-deficient mice exhibited less severe colitis and intestinal inflammation induced by dextran sodium sulfate. Given the crucial role of ASB proteins in inflammatory signaling pathways, our study offers insights into the immune regulation in pathogen infection and inflammatory disorders with therapeutic implications.
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15
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The Salmonella effector protein SopD targets Rab8 to positively and negatively modulate the inflammatory response. Nat Microbiol 2021; 6:658-671. [PMID: 33603205 PMCID: PMC8085087 DOI: 10.1038/s41564-021-00866-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 01/11/2021] [Indexed: 02/07/2023]
Abstract
The food-borne bacterial pathogen Salmonella Typhimurium uses a type III protein secretion system to deliver multiple proteins into host cells. These secreted effectors modulate the functions of host cells and activate specific signalling cascades that result in the production of pro-inflammatory cytokines and intestinal inflammation. Some of the Salmonella-encoded effectors counteract this inflammatory response and help to preserve host homeostasis. Here, we demonstrate that the Salmonella effector protein SopD, which is required for pathogenesis, functions to both activate and inhibit the inflammatory response by targeting the Rab8 GTPase, which is a negative regulator of inflammation. We show that SopD has GTPase-activating protein activity for Rab8 and, therefore, inhibits this GTPase and stimulates inflammation. We also show that SopD activates Rab8 by displacing it from its cognate guanosine dissociation inhibitor, resulting in the stimulation of a signalling cascade that suppresses inflammation. We solved the crystal structure of SopD in association with Rab8 to a resolution of 2.3 Å, which reveals a unique contact interface that underlies these complex interactions. These findings show the remarkable evolution of a bacterial effector protein to exert both agonistic and antagonistic activities towards the same host cellular target to modulate the inflammatory response.
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16
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Abstract
Pathogens have evolved smart strategies to invade hosts and hijack their immune responses. One such strategy is the targeting of the host RhoGTPases by toxins or virulence factors to hijack the cytoskeleton dynamic and immune processes. In response to this microbial attack, the host has evolved an elegant strategy to monitor the function of virulence factors and toxins by sensing the abnormal activity of RhoGTPases. This innate immune strategy of sensing bacterial effector targeting RhoGTPase appears to be a bona fide example of effector-triggered immunity (ETI). Here, we review recently discovered mechanisms by which the host can sense the activity of these toxins through NOD and NOD-like receptors (NLRs).
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Affiliation(s)
| | - Laurent Boyer
- Université Côte d’Azur, Inserm, C3M, Nice, France
- * E-mail:
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17
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Liu H, Liu K, Dong Z. The Role of p21-Activated Kinases in Cancer and Beyond: Where Are We Heading? Front Cell Dev Biol 2021; 9:641381. [PMID: 33796531 PMCID: PMC8007885 DOI: 10.3389/fcell.2021.641381] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/03/2021] [Indexed: 12/12/2022] Open
Abstract
The p21-activated kinases (PAKs), downstream effectors of Ras-related Rho GTPase Cdc42 and Rac, are serine/threonine kinases. Biologically, PAKs participate in various cellular processes, including growth, apoptosis, mitosis, immune response, motility, inflammation, and gene expression, making PAKs the nexus of several pathogenic and oncogenic signaling pathways. PAKs were proved to play critical roles in human diseases, including cancer, infectious diseases, neurological disorders, diabetes, pancreatic acinar diseases, and cardiac disorders. In this review, we systematically discuss the structure, function, alteration, and molecular mechanisms of PAKs that are involved in the pathogenic and oncogenic effects, as well as PAK inhibitors, which may be developed and deployed in cancer therapy, anti-viral infection, and other diseases. Furthermore, we highlight the critical questions of PAKs in future research, which provide an opportunity to offer input and guidance on new directions for PAKs in pathogenic, oncogenic, and drug discovery research.
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Affiliation(s)
- Hui Liu
- Department of Pathophysiology, School of Basic Medical Sciences, The Academy of Medical Science, College of Medical, Zhengzhou University, Zhengzhou, China
| | - Kangdong Liu
- Department of Pathophysiology, School of Basic Medical Sciences, The Academy of Medical Science, College of Medical, Zhengzhou University, Zhengzhou, China.,China-US (Henan) Hormel Cancer Institute, Zhengzhou, China
| | - Zigang Dong
- Department of Pathophysiology, School of Basic Medical Sciences, The Academy of Medical Science, College of Medical, Zhengzhou University, Zhengzhou, China.,China-US (Henan) Hormel Cancer Institute, Zhengzhou, China
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18
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Morenikeji OB, Bernard K, Strutton E, Wallace M, Thomas BN. Evolutionarily Conserved Long Non-coding RNA Regulates Gene Expression in Cytokine Storm During COVID-19. Front Bioeng Biotechnol 2021; 8:582953. [PMID: 33520952 PMCID: PMC7844208 DOI: 10.3389/fbioe.2020.582953] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/27/2020] [Indexed: 01/08/2023] Open
Abstract
Coronavirus is a family of viruses including alpha-, beta-, gamma-, delta-coronaviruses. Only alpha- and betacoronaviruses have been observed to infect humans. Past outbreaks of SARS-CoV and MERS-CoV, both betacoronavirus, are the result of a spillover from animals. Recently, a new strain termed SARS-CoV-2 emerged in December 2019 in Wuhan, China. Severe cases of COVID-19, the disease caused by SARS-CoV-2, lead to acute respiratory distress syndrome (ARDS). One contributor to the development of ARDS is cytokine storm, an overwhelming inflammatory immune response. Long non-coding RNAs (lncRNAs) are genetic regulatory elements that, among many functions, alter gene expression and cellular processes. lncRNAs identified to be pertinent in COVID-19 cytokine storm have the potential to serve as disease markers or drug targets. This project aims to computationally identify conserved lncRNAs potentially regulating gene expression in cytokine storm during COVID-19. We found 22 lncRNAs that can target 10 cytokines overexpressed in COVID-19 cytokine storm, 8 of which targeted two or more cytokine storm cytokines. In particular, the lncRNA non-coding RNA activated by DNA damage (NORAD), targeted five out of the ten identified cytokine storm cytokines, and is evolutionarily conserved across multiple species. These lncRNAs are ideal candidates for further in vitro and in vivo analysis.
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Affiliation(s)
| | - Kahleel Bernard
- Department of Biology, Hamilton College, Clinton, NY, United States
| | - Ellis Strutton
- Department of Biology, Hamilton College, Clinton, NY, United States
| | | | - Bolaji N. Thomas
- Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY, United States
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19
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Song J, Li Q, Everaert N, Liu R, Zheng M, Zhao G, Wen J. Dietary Inulin Supplementation Modulates Short-Chain Fatty Acid Levels and Cecum Microbiota Composition and Function in Chickens Infected With Salmonella. Front Microbiol 2021; 11:584380. [PMID: 33424783 PMCID: PMC7793945 DOI: 10.3389/fmicb.2020.584380] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/17/2020] [Indexed: 01/09/2023] Open
Abstract
The current study investigated the effects of inulin on the gut microbiota, microbiome functions, and short-chain fatty acids (SCFAs) levels in specific pathogen-free (SPF) chickens infected with Salmonella enteritidis (SE). SPF Arbor Acres chickens (n = 240, 1-day-old) were divided into four groups: a control group (CON) fed a basal diet without inulin supplementation or SE infection, and three groups fed a basal diet supplemented with inulin 0, 0.5, and 1% (SE, 0.5%InSE, 1%InSE, respectively) up to 28-days-old, followed by SE challenge at 28 days of age. Cecal SCFA contents and microbiome composition and function were analyzed at 1-day post-infection. The results showed that SE infection significantly decreased cecal butyrate concentrations compared with the CON group (p < 0.05), while inulin supplementation reversed these changes compared with the SE group (p < 0.05). Inulin supplementation at 1% significantly increased the abundances of Lactobacillus and Streptococcus, and significantly decreased the abundances of Subdoligranulum and Sellimonas compared with the SE group (p < 0.05). The functional profiles of microbial communities based on metagenomic sequencing analysis showed that SE infection significantly increased the abundances of pathways related to carbohydrate metabolism, amino acid metabolism, energy metabolism, metabolism of cofactors and vitamins, and glycan biosynthesis and metabolism (p < 0.05), and significantly decreased the abundances of pathways related to nucleotide metabolism, translation, and replication and repair compared with the CON group (p < 0.05), and these effects were reversed by inulin supplementation (0.5 and 1%) (p < 0.05). In conclusion, inulin modulated the dysbiosis induced by SE infection via affecting SCFA metabolism and microbial functional profiles.
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Affiliation(s)
- Jiao Song
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.,Precision Livestock and Nutrition Unit, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Qinghe Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Nadia Everaert
- Precision Livestock and Nutrition Unit, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Ranran Liu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Maiqing Zheng
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Guiping Zhao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jie Wen
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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20
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Chang H, He KY, Li C, Ni YY, Li MN, Chen L, Hou M, Zhou Z, Xu ZP, Ji MJ. P21 activated kinase-1 (PAK1) in macrophages is required for promotion of Th17 cell response during helminth infection. J Cell Mol Med 2020; 24:14325-14338. [PMID: 33124146 PMCID: PMC7753984 DOI: 10.1111/jcmm.16050] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 09/30/2020] [Accepted: 10/12/2020] [Indexed: 12/24/2022] Open
Abstract
CD4+T cells differentiate into distinct functional effector and inhibitory subsets are facilitated by distinct cytokine cues present at the time of antigen recognition. Maintaining a balance between T helper 17 (Th17) and regulatory T (Treg) cells are critical for the control of the immunopathogenesis of liver diseases. Here, by using the mouse model of helminth Schistosoma japonicum (Sjaponicum) infection, we show that the hepatic mRNA levels of P21‐activated kinase 1 (PAK1), a key regulator of the actin cytoskeleton, adhesion and cell motility, are significantly increased and associated with the development of liver pathology during Sjaponicum infection. In addition, PAK1‐deficient mice are prone to suppression of Th17 cell responses but increased Treg cells. Furthermore, PAK1 enhances macrophage activation through promoting IRF1 nuclear translocation in an NF‐κB‐dependent pathway, resulting in promoting Th17 cell differentiation through inducing IL‐6 production. These findings highlight the importance of PAK1 in macrophages fate determination and suggest that PAK1/IRF1 axis‐dependent immunomodulation can ameliorate certain T cell–based immune pathologies.
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Affiliation(s)
- Hao Chang
- Center for Global Health, Nanjing Medical University, Nanjing, China
| | - Kai-Yue He
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Chen Li
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Yang-Yue Ni
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Mai-Ning Li
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Lin Chen
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Min Hou
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Zikai Zhou
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhi-Peng Xu
- Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Min-Jun Ji
- Center for Global Health, Nanjing Medical University, Nanjing, China.,Department of Pathogen Biology, Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.,Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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21
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Kuss-Duerkop SK, Keestra-Gounder AM. NOD1 and NOD2 Activation by Diverse Stimuli: a Possible Role for Sensing Pathogen-Induced Endoplasmic Reticulum Stress. Infect Immun 2020; 88:e00898-19. [PMID: 32229616 PMCID: PMC7309630 DOI: 10.1128/iai.00898-19] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Prompt recognition of microbes by cells is critical to eliminate invading pathogens. Some cell-associated pattern recognition receptors (PRRs) recognize and respond to microbial ligands. However, others can respond to cellular perturbations, such as damage-associated molecular patterns (DAMPs). Nucleotide oligomerization domains 1 and 2 (NOD1/2) are PRRs that recognize and respond to multiple stimuli of microbial and cellular origin, such as bacterial peptidoglycan, viral infections, parasitic infections, activated Rho GTPases, and endoplasmic reticulum (ER) stress. How NOD1/2 are stimulated by such diverse stimuli is not fully understood but may partly rely on cellular changes during infection that result in ER stress. NOD1/2 are ER stress sensors that facilitate proinflammatory responses for pathogen clearance; thus, NOD1/2 may help mount broad antimicrobial responses through detection of ER stress, which is often induced during a variety of infections. Some pathogens may subvert this response to promote infection through manipulation of NOD1/2 responses to ER stress that lead to apoptosis. Here, we review NOD1/2 stimuli and cellular responses. Furthermore, we discuss pathogen-induced ER stress and how it might potentiate NOD1/2 signaling.
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Affiliation(s)
- Sharon K Kuss-Duerkop
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - A Marijke Keestra-Gounder
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
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22
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Fattinger SA, Böck D, Di Martino ML, Deuring S, Samperio Ventayol P, Ek V, Furter M, Kreibich S, Bosia F, Müller-Hauser AA, Nguyen BD, Rohde M, Pilhofer M, Hardt WD, Sellin ME. Salmonella Typhimurium discreet-invasion of the murine gut absorptive epithelium. PLoS Pathog 2020; 16:e1008503. [PMID: 32365138 PMCID: PMC7224572 DOI: 10.1371/journal.ppat.1008503] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 05/14/2020] [Accepted: 03/26/2020] [Indexed: 01/15/2023] Open
Abstract
Salmonella enterica serovar Typhimurium (S.Tm) infections of cultured cell lines have given rise to the ruffle model for epithelial cell invasion. According to this model, the Type-Three-Secretion-System-1 (TTSS-1) effectors SopB, SopE and SopE2 drive an explosive actin nucleation cascade, resulting in large lamellipodia- and filopodia-containing ruffles and cooperative S.Tm uptake. However, cell line experiments poorly recapitulate many of the cell and tissue features encountered in the host’s gut mucosa. Here, we employed bacterial genetics and multiple imaging modalities to compare S.Tm invasion of cultured epithelial cell lines and the gut absorptive epithelium in vivo in mice. In contrast to the prevailing ruffle-model, we find that absorptive epithelial cell entry in the mouse gut occurs through “discreet-invasion”. This distinct entry mode requires the conserved TTSS-1 effector SipA, involves modest elongation of local microvilli in the absence of expansive ruffles, and does not favor cooperative invasion. Discreet-invasion preferentially targets apicolateral hot spots at cell–cell junctions and shows strong dependence on local cell neighborhood. This proof-of-principle evidence challenges the current model for how S.Tm can enter gut absorptive epithelial cells in their intact in vivo context. Bacterial pathogens can use secreted effector molecules to drive entry into host cells. Studies of the intestinal pathogen S.Tm have been central to uncover the mechanistic basis for the entry process. More than two decades of research have resulted in a detailed model for how S.Tm invades gut epithelial cells through effector triggering of large Rho-GTPase-dependent actin ruffles. However, the evidence for this model comes predominantly from studies in cultured cell lines. These experimental systems lack many of the architectural and signaling features of the intact gut epithelium. Our study surprisingly reveals that in the intact mouse gut, S.Tm invades absorptive epithelial cells through a process that does not require the Rho-GTPase-activating effectors and can proceed in the absence of the prototypical ruffling response. Instead, S.Tm exploits another effector, SipA, to sneak in through discreet entry structures close to cell–cell junctions. Our results challenge the current model for S.Tm epithelial cell entry and emphasizes the need of taking a physiological host cell context into account when studying bacterium–host cell interactions.
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Affiliation(s)
- Stefan A. Fattinger
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Desirée Böck
- Institute of Molecular Biology & Biophysics, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Maria Letizia Di Martino
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Sabrina Deuring
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Pilar Samperio Ventayol
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Viktor Ek
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Markus Furter
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Saskia Kreibich
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Francesco Bosia
- Institute of Molecular Biology & Biophysics, Department of Biology, ETH Zürich, Zürich, Switzerland
| | | | - Bidong D. Nguyen
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Martin Pilhofer
- Institute of Molecular Biology & Biophysics, Department of Biology, ETH Zürich, Zürich, Switzerland
- * E-mail: (MP); (WDH); (MES)
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
- * E-mail: (MP); (WDH); (MES)
| | - Mikael E. Sellin
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- * E-mail: (MP); (WDH); (MES)
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23
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Bleves S, Galán JE, Llosa M. Bacterial injection machines: Evolutionary diverse but functionally convergent. Cell Microbiol 2020; 22:e13157. [PMID: 31891220 PMCID: PMC7138736 DOI: 10.1111/cmi.13157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 12/19/2019] [Indexed: 12/23/2022]
Abstract
Many human pathogens use Type III, Type IV, and Type VI secretion systems to deliver effectors into their target cells. The contribution of these secretion systems to microbial virulence was the main focus of a workshop organised by the International University of Andalusia in Spain. The meeting addressed structure-function, substrate recruitment, and translocation processes, which differ widely on the different secretion machineries, as well as the nature of the translocated effectors and their roles in subverting the host cell. An excellent panel of worldwide speakers presented the state of the art of the field, highlighting the involvement of bacterial secretion in human disease and discussing mechanistic aspects of bacterial pathogenicity, which can provide the bases for the development of novel antivirulence strategies.
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Affiliation(s)
- Sophie Bleves
- LISM (Laboratoire d’Ingénierie des Systèmes Macromoléculaires-UMR7255), IMM (Institut de Microbiologie de la Méditerranée), Aix-Marseille Univ and CNRS, Marseille, France
| | - Jorge E. Galán
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, USA
| | - Matxalen Llosa
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC-SODERCAN, Santander, Spain
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Lopes Fischer N, Naseer N, Shin S, Brodsky IE. Effector-triggered immunity and pathogen sensing in metazoans. Nat Microbiol 2019; 5:14-26. [DOI: 10.1038/s41564-019-0623-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 10/29/2019] [Indexed: 01/06/2023]
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Molecular Mechanisms That Define Redox Balance Function in Pathogen-Host Interactions-Is There a Role for Dietary Bioactive Polyphenols? Int J Mol Sci 2019; 20:ijms20246222. [PMID: 31835548 PMCID: PMC6940965 DOI: 10.3390/ijms20246222] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/02/2019] [Accepted: 12/03/2019] [Indexed: 01/01/2023] Open
Abstract
To ensure a functional immune system, the mammalian host must detect and respond to the presence of pathogenic bacteria during infection. This is accomplished in part by generating reactive oxygen species (ROS) that target invading bacteria; a process that is facilitated by NADPH oxidase upregulation. Thus, bacterial pathogens must overcome the oxidative burst produced by the host innate immune cells in order to survive and proliferate. In this way, pathogenic bacteria develop virulence, which is related to the affinity to secrete effector proteins against host ROS in order to facilitate microbial survival in the host cell. These effectors scavenge the host generated ROS directly, or alternatively, manipulate host cell signaling mechanisms designed to benefit pathogen survival. The redox-balance of the host is important for the regulation of cell signaling activities that include mitogen-activated protein kinase (MAPK), p21-activated kinase (PAK), phosphatidylinositol 3-kinase (PI3K)/Akt, and nuclear factor κB (NF-κB) pathways. An understanding of the function of pathogenic effectors to divert host cell signaling is important to ascertain the mechanisms underlying pathogen virulence and the eventual host–pathogen relationship. Herein, we examine the effectors produced by the microbial secretion system, placing emphasis on how they target molecular signaling mechanisms involved in a host immune response. Moreover, we discuss the potential impact of bioactive polyphenols in modulating these molecular interactions that will ultimately influence pathogen virulence.
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West KO, Scott HM, Torres-Odio S, West AP, Patrick KL, Watson RO. The Splicing Factor hnRNP M Is a Critical Regulator of Innate Immune Gene Expression in Macrophages. Cell Rep 2019; 29:1594-1609.e5. [PMID: 31693898 PMCID: PMC6981299 DOI: 10.1016/j.celrep.2019.09.078] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/13/2019] [Accepted: 09/26/2019] [Indexed: 12/16/2022] Open
Abstract
While transcriptional control of innate immune gene expression is well characterized, almost nothing is known about how pre-mRNA splicing decisions influence, or are influenced by, macrophage activation. Here, we demonstrate that the splicing factor hnRNP M is a critical repressor of innate immune gene expression and that its function is regulated by pathogen sensing cascades. Loss of hnRNP M led to hyperinduction of a unique regulon of inflammatory and antimicrobial genes following diverse innate immune stimuli. While mutating specific serines on hnRNP M had little effect on its ability to control pre-mRNA splicing or transcript levels of housekeeping genes in resting macrophages, it greatly impacted the protein's ability to dampen induction of specific innate immune transcripts following pathogen sensing. These data reveal a previously unappreciated role for pattern recognition receptor signaling in controlling splicing factor phosphorylation and establish pre-mRNA splicing as a critical regulatory node in defining innate immune outcomes.
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Affiliation(s)
- Kelsi O West
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Haley M Scott
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Sylvia Torres-Odio
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - A Phillip West
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Kristin L Patrick
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA.
| | - Robert O Watson
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA.
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Ganesan S, Roy CR. Host cell depletion of tryptophan by IFNγ-induced Indoleamine 2,3-dioxygenase 1 (IDO1) inhibits lysosomal replication of Coxiella burnetii. PLoS Pathog 2019; 15:e1007955. [PMID: 31461509 PMCID: PMC6736304 DOI: 10.1371/journal.ppat.1007955] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 09/10/2019] [Accepted: 07/01/2019] [Indexed: 12/20/2022] Open
Abstract
Most intracellular pathogens that reside in a vacuole prevent transit of their compartment to lysosomal organelles. Effector mechanisms induced by the pro-inflammatory cytokine Interferon-gamma (IFNγ) can promote the delivery of pathogen-occupied vacuoles to lysosomes for proteolytic degradation and are therefore important for host defense against intracellular pathogens. The bacterial pathogen Coxiella burnetii is unique in that, transport to the lysosome is essential for replication. The bacterium modulates membrane traffic to create a specialized autophagolysosomal compartment called the Coxiella-containing vacuole (CCV). Importantly, IFNγ signaling inhibits intracellular replication of C. burnetii, raising the question of which IFNγ-activated mechanisms restrict replication of a lysosome-adapted pathogen. To address this question, siRNA was used to silence a panel of IFNγ-induced genes in HeLa cells to identify genes required for restriction of C. burnetii intracellular replication. This screen demonstrated that Indoleamine 2,3-dioxygenase 1 (IDO1) contributes to IFNγ-mediated restriction of C. burnetii. IDO1 is an enzyme that catabolizes cellular tryptophan to kynurenine metabolites thereby reducing tryptophan availability in cells. Cells deficient in IDO1 function were more permissive for C. burnetii replication when treated with IFNγ, and supplementing IFNγ-treated cells with tryptophan enhanced intracellular replication. Additionally, ectopic expression of IDO1 in host cells was sufficient to restrict replication of C. burnetii in the absence of IFNγ signaling. Using differentiated THP1 macrophage-like cells it was determined that IFNγ-activation resulted in IDO1 production, and that supplementation of IFNγ-activated THP1 cells with tryptophan enhanced C. burnetii replication. Thus, this study identifies IDO1 production as a key cell-autonomous defense mechanism that limits infection by C. burnetii, which suggests that peptides derived from hydrolysis of proteins in the CCV do not provide an adequate supply of tryptophan for bacterial replication.
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Affiliation(s)
- Sandhya Ganesan
- Department of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Craig R. Roy
- Department of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
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Parween F, Yadav J, Qadri A. The Virulence Polysaccharide of Salmonella Typhi Suppresses Activation of Rho Family GTPases to Limit Inflammatory Responses From Epithelial Cells. Front Cell Infect Microbiol 2019; 9:141. [PMID: 31134159 PMCID: PMC6517557 DOI: 10.3389/fcimb.2019.00141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/16/2019] [Indexed: 12/20/2022] Open
Abstract
Vi capsular polysaccharide (Vi) is a major virulence factor of human typhoid-causing pathogen Salmonella enterica serovar Typhi (S. Typhi). It distinguishes S. Typhi from closely related non-typhoidal Salmonella serovars such as S. Typhimurium which do not normally cause systemic infection in humans. Vi not only forms a capsule around S. Typhi but it is also readily released from this pathogen. We have previously reported that Vi targets prohibitin to inhibit cellular responses activated through immune receptors. Here, we show that engagement of membrane prohibitin with Vi prevents Salmonella-induced activation of small Rho-family GTPases, Rac1, and Cdc42, and suppresses actin cytoskeletal rearrangements resulting in reduced invasion and highly subdued inflammatory responses. Cells infected with S. Typhimurium in the presence of Vi show poor activation of NF-kB and MAP-kinase pathways of intracellular signaling. Treatment with Vi brings about redistribution of Rac-1, prohibitin, and ganglioside GM1 in membrane raft domains. Vi-mediated interference with activation of Rho-family GTPases represents a previously unrecognized mechanism by which S. Typhi can limit its invasion and alarming of the host.
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Affiliation(s)
- Farhat Parween
- Hybridoma Laboratory, National Institute of Immunology, New Delhi, India
| | - Jitender Yadav
- Hybridoma Laboratory, National Institute of Immunology, New Delhi, India
| | - Ayub Qadri
- Hybridoma Laboratory, National Institute of Immunology, New Delhi, India
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