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1.
Aging (Albany NY) ; 13(18): 21838-21854, 2021 09 16.
Article in English | MEDLINE | ID: covidwho-1417382

ABSTRACT

Senescent cells, which arise due to damage-associated signals, are apoptosis-resistant and can express a pro-inflammatory, tissue-destructive senescence-associated secretory phenotype (SASP). We recently reported that a component of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surface protein, S1, can amplify the SASP of senescent cultured human cells and that a related mouse ß-coronavirus, mouse hepatitis virus (MHV), increases SASP factors and senescent cell burden in infected mice. Here, we show that SARS-CoV-2 induces senescence in human non-senescent cells and exacerbates the SASP in human senescent cells through Toll-like receptor-3 (TLR-3). TLR-3, which senses viral RNA, was increased in human senescent compared to non-senescent cells. Notably, genetically or pharmacologically inhibiting TLR-3 prevented senescence induction and SASP amplification by SARS-CoV-2 or Spike pseudotyped virus. While an artificial TLR-3 agonist alone was not sufficient to induce senescence, it amplified the SASP in senescent human cells. Consistent with these findings, lung p16INK4a+ senescent cell burden was higher in patients who died from acute SARS-CoV-2 infection than other causes. Our results suggest that induction of cellular senescence and SASP amplification through TLR-3 contribute to SARS-CoV-2 morbidity, indicating that clinical trials of senolytics and/or SASP/TLR-3 inhibitors for alleviating acute and long-term SARS-CoV-2 sequelae are warranted.


Subject(s)
COVID-19/virology , Cellular Senescence , SARS-CoV-2/pathogenicity , Toll-Like Receptor 3/metabolism , Aging , Animals , Apoptosis , COVID-19/drug therapy , COVID-19/metabolism , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Humans , Inflammation , Lung/metabolism , Mice , Phenotype , Viral Proteins
2.
J Biol Chem ; 297(2): 100925, 2021 08.
Article in English | MEDLINE | ID: covidwho-1336599

ABSTRACT

Apart from prevention using vaccinations, the management options for COVID-19 remain limited. In retrospective cohort studies, use of famotidine, a specific oral H2 receptor antagonist (antihistamine), has been associated with reduced risk of intubation and death in patients hospitalized with COVID-19. In a case series, nonhospitalized patients with COVID-19 experienced rapid symptom resolution after taking famotidine, but the molecular basis of these observations remains elusive. Here we show using biochemical, cellular, and functional assays that famotidine has no effect on viral replication or viral protease activity. However, famotidine can affect histamine-induced signaling processes in infected Caco2 cells. Specifically, famotidine treatment inhibits histamine-induced expression of Toll-like receptor 3 (TLR3) in SARS-CoV-2 infected cells and can reduce TLR3-dependent signaling processes that culminate in activation of IRF3 and the NF-κB pathway, subsequently controlling antiviral and inflammatory responses. SARS-CoV-2-infected cells treated with famotidine demonstrate reduced expression levels of the inflammatory mediators CCL-2 and IL6, drivers of the cytokine release syndrome that precipitates poor outcome for patients with COVID-19. Given that pharmacokinetic studies indicate that famotidine can reach concentrations in blood that suffice to antagonize histamine H2 receptors expressed in mast cells, neutrophils, and eosinophils, these observations explain how famotidine may contribute to the reduced histamine-induced inflammation and cytokine release, thereby improving the outcome for patients with COVID-19.


Subject(s)
Famotidine/pharmacology , Histamine Antagonists/pharmacology , SARS-CoV-2/drug effects , Toll-Like Receptor 3/metabolism , A549 Cells , Binding Sites , Caco-2 Cells , Chemokine CCL2/metabolism , Coronavirus 3C Proteases/metabolism , HeLa Cells , Humans , Interferon Regulatory Factor-3/metabolism , Interleukin-6/metabolism , Molecular Docking Simulation , NF-kappa B/metabolism , Protein Binding , SARS-CoV-2/physiology , Signal Transduction , Toll-Like Receptor 3/chemistry , Virus Replication
3.
Eur J Med Chem ; 224: 113684, 2021 Nov 15.
Article in English | MEDLINE | ID: covidwho-1292698

ABSTRACT

Respiratory syncytial virus (RSV) causes serious lower respiratory tract infections. Currently, the only clinical anti-RSV drug is ribavirin, but ribavirin has serious toxic side effect and can only be used by critically ill patients. A series of benzimidazole derivatives were synthesized starting from 1,4:3,6-dianhydro-d-fructose and a variety of o-phenylenediamines. Evaluation of their antiviral activity showed that compound a27 had the highest antiviral activity with a half maximal effective concentration (EC50) of 9.49 µM. Investigation of the antiviral mechanism of compound a27 indicated that it can inhibit the replication of RSV by inhibiting apoptosis and autophagy pathways. Retinoic acid-inducible gene (RIG)-I, TNF receptor associated factor (TRAF)-3, TANK binding kinase (TBK)-1, interferon regulatory factor (IRF)-3, nuclear factor Kappa-B (NF-κB), interferon (IFN)-ß, Toll-like receptor (TLR)-3, interleukin (IL)-6 were suppressed at the cellular level. Mouse lung tissue was subjected to hematoxylin and eosin (HE) staining and immunohistochemistry, which showed that RSV antigen and M gene expression could be reduced by compound a27. Decreased expression of RIG-I, IRF-3, IFN-ß, TLR-3, IL-6, interleukin (IL)-8, interleukin (IL)-10, inducible nitric oxide synthase (iNOS) and tumor necrosis factor (TNF)-α was also found in vivo.


Subject(s)
Antiviral Agents/chemical synthesis , Benzimidazoles/chemistry , Drug Design , Animals , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Apoptosis/drug effects , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Benzimidazoles/therapeutic use , Cell Line , Cytokines/metabolism , Humans , Isomerism , Lung/metabolism , Lung/pathology , Mice , Molecular Conformation , Reactive Oxygen Species/metabolism , Respiratory Syncytial Virus Infections/drug therapy , Respiratory Syncytial Virus Infections/pathology , Respiratory Syncytial Virus, Human/drug effects , Respiratory Syncytial Virus, Human/physiology , Structure-Activity Relationship , Toll-Like Receptor 3/metabolism , Virus Replication/drug effects
4.
J Interferon Cytokine Res ; 40(12): 549-554, 2020 12.
Article in English | MEDLINE | ID: covidwho-990532

ABSTRACT

Coronavirus disease 2019 (COVID-19) has spread rapidly and become a pandemic. Caused by a novel human coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), severe COVID-19 is characterized by cytokine storm syndromes due to innate immune activation. Primary immunodeficiency (PID) cases represent a special patient population whose impaired immune system might make them susceptible to severe infections, posing a higher risk to COVID-19, but this could also lead to suppressed inflammatory responses and cytokine storm. It remains an open question as to whether the impaired immune system constitutes a predisposing or protective factor for PID patients when facing SARS-CoV-2 infection. After literature review, it was found that, similar to other patient populations with different comorbidities, PID patients may be susceptible to SARS-CoV-2 infection. Their varied immune status, however, may lead to different disease severity and outcomes after SARS-CoV-2 infection. PID patients with deficiency in antiviral innate immune signaling [eg, Toll-like receptor (TLR)3, TLR7, or interferon regulatory factor 7 (IRF7)] or interferon signaling (IFNAR2) may be linked to severe COVID-19. Because of its anti-infection, anti-inflammatory, and immunomodulatory effects, routine intravenous immunoglobulin therapy may provide some protective effects to the PID patients.


Subject(s)
COVID-19/complications , COVID-19/immunology , Immune System , Inflammation , Primary Immunodeficiency Diseases/complications , Primary Immunodeficiency Diseases/immunology , Comorbidity , Disease Susceptibility , Humans , Immunity, Innate , Immunoglobulins, Intravenous/metabolism , Interferon Regulatory Factor-7/metabolism , Pandemics , Receptor, Interferon alpha-beta/metabolism , Risk , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 7/metabolism
5.
Kidney Blood Press Res ; 46(1): 74-83, 2021.
Article in English | MEDLINE | ID: covidwho-978847

ABSTRACT

INTRODUCTION: Various viruses including a novel coronavirus (SARS-CoV-2) can infect the kidney. When viruses invade the glomeruli from the bloodstream, glomerular endothelial cells (GECs) initiate the innate immune reactions. We investigated the expression of interferon (IFN)-induced protein with tetratricopeptide repeats (IFIT) 1/2/3, antiviral molecules, in human GECs treated with a toll-like receptor (TLR) 3 agonist. Role of IFIT1/2/3 in the expression of C-X-C motif chemokine ligand 10 (CXCL10) was also examined. METHODS: Human GECs were cultured and stimulated with polyinosinic-polycytidylic acid (poly IC), a synthetic TLR3 agonist. Real-time qPCR, Western blotting, and ELISA were used to examine the expression of IFIT1/2/3, IFN-ß, and CXCL10. RNA interference against IFN-ß or IFIT1/2/3 was also performed. RESULTS: Expression of IFIT1/2/3 and CXCL10 was induced by poly IC in GECs. The inductions were inhibited by RNA interfering of IFN-ß. Knockdown of IFIT1/2/3 decreased the CXCL10 expression. Knockdown of IFIT3 decreased the expression of IFIT1 and IFIT2 proteins. CONCLUSION: IFIT1/2/3 and CXCL10 were induced by poly IC via IFN-ß in GECs. IFIT1/2/3 may increase the expression of CXCL10 which induces lymphocyte chemotaxis and may inhibit the replication of infected viruses. These molecules may play a role in GEC innate immune reactions in response to viruses.


Subject(s)
Adaptor Proteins, Signal Transducing/biosynthesis , Apoptosis Regulatory Proteins/biosynthesis , Chemokine CXCL10/biosynthesis , Intracellular Signaling Peptides and Proteins/biosynthesis , Kidney Glomerulus/metabolism , RNA-Binding Proteins/biosynthesis , Toll-Like Receptor 3/agonists , Adaptor Proteins, Signal Transducing/genetics , Apoptosis Regulatory Proteins/genetics , Cells, Cultured , Chemokine CXCL10/genetics , Dose-Response Relationship, Drug , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Gene Expression , Humans , Intracellular Signaling Peptides and Proteins/genetics , Kidney Glomerulus/cytology , Kidney Glomerulus/drug effects , Poly I-C/pharmacology , RNA-Binding Proteins/genetics , Toll-Like Receptor 3/metabolism
6.
Sci Rep ; 10(1): 20864, 2020 11 30.
Article in English | MEDLINE | ID: covidwho-951878

ABSTRACT

Coronavirus disease 2019 (COVID-19) is an acute pneumonic disease, with no prophylactic or specific therapeutical solution. Effective and rapid countermeasure against the spread of the disease's associated virus, SARS-CoV-2, requires to incorporate the computational approach. In this study, we employed various immunoinformatics tools to design a multi-epitope vaccine polypeptide with the highest potential for activating the human immune system against SARS-CoV-2. The initial epitope set was extracted from the whole set of viral structural proteins. Potential non-toxic and non-allergenic T-cell and B-cell binding and cytokine inducing epitopes were then identified through a priori prediction. Selected epitopes were bound to each other with appropriate linkers, followed by appending a suitable adjuvant to increase the immunogenicity of the vaccine polypeptide. Molecular modelling of the 3D structure of the vaccine construct, docking, molecular dynamics simulations and free energy calculations confirmed that the vaccine peptide had high affinity for Toll-like receptor 3 binding, and that the vaccine-receptor complex was highly stable. As our vaccine polypeptide design captures the advantages of structural epitopes and simultaneously integrates precautions to avoid relevant side effects, it is suggested to be promising for elicitation of an effective and safe immune response against SARS-CoV-2 in vivo.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Vaccines, Subunit/immunology , Viral Structural Proteins/immunology , Computational Biology , Epitopes, B-Lymphocyte/immunology , Epitopes, T-Lymphocyte/immunology , Humans , Immunogenicity, Vaccine , Models, Molecular , Molecular Docking Simulation , Molecular Dynamics Simulation , Toll-Like Receptor 3/metabolism
8.
Infect Genet Evol ; 85: 104507, 2020 11.
Article in English | MEDLINE | ID: covidwho-731865

ABSTRACT

The COVID-19 pandemic highlighted healthcare disparities in multiple countries. As such morbidity and mortality vary significantly around the globe between populations and ethnic groups. Underlying medical conditions and environmental factors contribute higher incidence in some populations and a genetic predisposition may play a role for severe cases with respiratory failure. Here we investigated whether genetic variation in the key genes for viral entry to host cells-ACE2 and TMPRSS2-and sensing of viral genomic RNAs (i.e., TLR3/7/8) could explain the variation in incidence across diverse ethnic groups. Overall, these genes are under strong selection pressure and have very few nonsynonymous variants in all populations. Genetic determinant for the binding affinity between SARS-CoV-2 and ACE2 does not show significant difference between populations. Non-genetic factors are likely to contribute differential population characteristics affected by COVID-19. Nonetheless, a systematic mutagenesis study on the receptor binding domain of ACE2 is required to understand the difference in host-viral interaction across populations.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , SARS-CoV-2/physiology , Serine Endopeptidases/genetics , Toll-Like Receptors/genetics , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Binding Sites , Humans , Mutagenesis, Site-Directed , Protein Binding , Protein Domains , Selection, Genetic , Serine Endopeptidases/metabolism , Toll-Like Receptor 3/chemistry , Toll-Like Receptor 3/genetics , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 7/chemistry , Toll-Like Receptor 7/genetics , Toll-Like Receptor 7/metabolism , Toll-Like Receptor 8/chemistry , Toll-Like Receptor 8/genetics , Toll-Like Receptor 8/metabolism , Toll-Like Receptors/chemistry , Toll-Like Receptors/metabolism , Virus Internalization
9.
Science ; 369(6504): 706-712, 2020 08 07.
Article in English | MEDLINE | ID: covidwho-717344

ABSTRACT

Viral infections of the lower respiratory tract are a leading cause of mortality. Mounting evidence indicates that most severe cases are characterized by aberrant immune responses and do not depend on viral burden. In this study, we assessed how type III interferons (IFN-λ) contribute to the pathogenesis induced by RNA viruses. We report that IFN-λ is present in the lower, but not upper, airways of patients with coronavirus disease 2019 (COVID-19). In mice, we demonstrate that IFN-λ produced by lung dendritic cells in response to a synthetic viral RNA induces barrier damage, causing susceptibility to lethal bacterial superinfections. These findings provide a strong rationale for rethinking the pathophysiological role of IFN-λ and its possible use in clinical practice against endemic viruses, such as influenza virus as well as the emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.


Subject(s)
Betacoronavirus , Coronavirus Infections/immunology , Coronavirus Infections/metabolism , Dendritic Cells/metabolism , Interferons/physiology , Lung/metabolism , Lung/pathology , Pneumonia, Viral/immunology , Pneumonia, Viral/metabolism , Animals , Bronchoalveolar Lavage Fluid/immunology , COVID-19 , Cell Proliferation , Cytokines/metabolism , Humans , Interferon Type I/metabolism , Interferons/metabolism , Lung/immunology , Mice , Mice, Inbred C57BL , Nasopharynx/immunology , Pandemics , Poly I-C/administration & dosage , Respiratory Mucosa/pathology , SARS-CoV-2 , Signal Transduction , Staphylococcal Infections/metabolism , Superinfection , Toll-Like Receptor 3/metabolism
10.
Mol Cell Endocrinol ; 515: 110917, 2020 09 15.
Article in English | MEDLINE | ID: covidwho-661768

ABSTRACT

Obesity patients are more susceptible to develop COVID-19 severe outcome due to the role of angiotensin-converting enzyme 2 (ACE2) in the viral infection. ACE2 is regulated in the human cells by different genes associated with increased (TLR3, HAT1, HDAC2, KDM5B, SIRT1, RAB1A, FURIN and ADAM10) or decreased (TRIB3) virus replication. RNA-seq data revealed 14857 genes expressed in human subcutaneous adipocytes, including genes mentioned above. Irisin treatment increased by 3-fold the levels of TRIB3 transcript and decreased the levels of other genes. The decrease in FURIN and ADAM10 expression enriched diverse biological processes, including extracellular structure organization. Our results, in human subcutaneous adipocytes cell culture, indicate a positive effect of irisin on the expression of multiple genes related to viral infection by SARS-CoV-2; furthermore, translatable for other tissues and organs targeted by the novel coronavirus and present, thus, promising approaches for the treatment of COVID-19 infection as therapeutic strategy to decrease ACE2 regulatory genes.


Subject(s)
Adipocytes/drug effects , Fibronectins/pharmacology , Gene Expression Regulation/drug effects , ADAM10 Protein/genetics , ADAM10 Protein/metabolism , Adipocytes/cytology , Adipocytes/metabolism , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Angiotensin-Converting Enzyme 2 , Betacoronavirus/genetics , Betacoronavirus/metabolism , COVID-19 , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cells, Cultured , Coronavirus Infections/virology , Fibronectins/genetics , Fibronectins/metabolism , Furin/genetics , Furin/metabolism , Gene Ontology , Histone Acetyltransferases/genetics , Histone Acetyltransferases/metabolism , Histone Deacetylase 2/genetics , Histone Deacetylase 2/metabolism , Humans , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Models, Biological , Molecular Sequence Annotation , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Obesity/virology , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/virology , /genetics , Repressor Proteins/genetics , Repressor Proteins/metabolism , SARS-CoV-2 , Signal Transduction , Sirtuin 1/genetics , Sirtuin 1/metabolism , Toll-Like Receptor 3/genetics , Toll-Like Receptor 3/metabolism , rab1 GTP-Binding Proteins/genetics , rab1 GTP-Binding Proteins/metabolism
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