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1.
Sci Rep ; 12(1): 5496, 2022 03 31.
Article in English | MEDLINE | ID: covidwho-1768853

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is accompanied by chronic neurological sequelae such as cognitive decline and mood disorder, but the underlying mechanisms have not yet been elucidated. We explored the possibility that the brain-infiltrating SARS-CoV-2 spike protein contributes to the development of neurological symptoms observed in COVID-19 patients in this study. Our behavioral study showed that administration of SARS-CoV-2 spike protein S1 subunit (S1 protein) to mouse hippocampus induced cognitive deficit and anxiety-like behavior in vivo. These neurological symptoms were accompanied by neuronal cell death in the dorsal and ventral hippocampus as well as glial cell activation. Interestingly, the S1 protein did not directly induce hippocampal cell death in vitro. Rather, it exerted neurotoxicity via glial cell activation, partially through interleukin-1ß induction. In conclusion, our data suggest a novel pathogenic mechanism for the COVID-19-associated neurological symptoms that involves glia activation and non-cell autonomous hippocampal neuronal death by the brain-infiltrating S1 protein.


Subject(s)
COVID-19 , Cognitive Dysfunction , Animals , Antibodies, Viral/metabolism , Anxiety , Cell Death , Cognition , Cognitive Dysfunction/etiology , Hippocampus/metabolism , Humans , Membrane Glycoproteins/metabolism , Mice , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism , Viral Envelope Proteins/metabolism
2.
Crit Rev Immunol ; 41(3): 43-56, 2021.
Article in English | MEDLINE | ID: covidwho-1753247

ABSTRACT

Pathogenic coronaviruses (CoVs) have caused human respiratory infections and severe disease outbreaks in the past two decades. Recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in humans shows high transmissibility causing a wide range of clinical outcomes, named coronavirus disease-2019 (COVID-19), which emerged into an ongoing pandemic. Innate immune sensing of SARS-CoV-2 infection is critical for mounting antiviral and inflammatory responses to restrict the viral spread and initiate lung tissue repair processes. However, excessive cytokine and chemokine levels and dysregulated inflammatory immune cell function in the lungs are associated with respiratory failure and severe COVID-19. Thus, there is a tremendous need for understanding SARS-CoV-2-host interactions determining the aberrant inflammatory responses and loss of respiratory function. In this article, we discuss host innate immune responses determining dysregulated inflammation and immunopathology during SARS-CoV-2 infection. We also provide the perspective for the inflammatory cell death contribution for this immunopathology. Virus-induced acute host responses are complex, and elucidating this complex mechanism facilitates safe therapeutic interventions to alleviate inflammation-mediated immunopathology during pathogenic virus infections.


Subject(s)
COVID-19 , Immunity, Innate , Inflammation , SARS-CoV-2 , Cell Death , Cytokines/metabolism , Humans , Lung , SARS-CoV-2/pathogenicity
3.
Immunity ; 55(3): 382-384, 2022 03 08.
Article in English | MEDLINE | ID: covidwho-1747889

ABSTRACT

Macrophage activation is essential for effective immunity to infection but can also contribute to disease through incompletely understood mechanisms. In this issue of Immunity, Simpson et al. reveal that death of activated macrophages integrates extrinsic and intrinsic pathways of apoptosis that contribute to damaging host responses.


Subject(s)
Interferon-gamma , Macrophage Activation , Apoptosis , Caspase 8/metabolism , Cell Death , Interferon-gamma/metabolism , Ligands , Macrophages/immunology
4.
Viruses ; 14(2)2022 02 04.
Article in English | MEDLINE | ID: covidwho-1674821

ABSTRACT

WHO has declared COVID-19 as a worldwide, public health emergency. The elderly, pregnant women, and people with associated co-morbidities, including pulmonary disease, heart failure, diabetes, and cancer are the most predisposed population groups to infection. Cell-free DNA is a very commonly applied marker, which is elevated in various pathological conditions. However, it has a much higher sensitivity than standard biochemical markers. cfDNA appears to be an effective marker of COVID-19 complications, and also serves as a marker of certain underlying health conditions and risk factors of severe illness during COVID-19 infection. We aimed to present the possible mechanisms and sources of cfDNA released during moderate and severe infections. Moreover, we attempt to verify how efficiently cfDNA increase could be applied in COVID-19 risk assessment and how it corresponds with epidemiological data.


Subject(s)
COVID-19/diagnosis , Cell-Free Nucleic Acids/analysis , Cell-Free Nucleic Acids/blood , SARS-CoV-2/pathogenicity , COVID-19/blood , COVID-19/complications , Cell Death/genetics , Female , Genetic Markers , Humans , Pregnancy , Pregnant Women , Risk Assessment , Risk Factors
5.
Virology ; 568: 13-22, 2022 03.
Article in English | MEDLINE | ID: covidwho-1639193

ABSTRACT

Heightened inflammatory response is a prominent feature of severe COVID-19 disease. We report that the SARS-CoV-2 ORF3a viroporin activates the NLRP3 inflammasome, the most promiscuous of known inflammasomes. Ectopically expressed ORF3a triggers IL-1ß expression via NFκB, thus priming the inflammasome. ORF3a also activates the NLRP3 inflammasome but not NLRP1 or NLRC4, resulting in maturation of IL-1ß and cleavage/activation of Gasdermin. Notably, ORF3a activates the NLRP3 inflammasome via both ASC-dependent and -independent modes. This inflammasome activation requires efflux of potassium ions and oligomerization between the kinase NEK7 and NLRP3. Importantly, infection of epithelial cells with SARS-CoV-2 similarly activates the NLRP3 inflammasome. With the NLRP3 inhibitor MCC950 and select FDA-approved oral drugs able to block ORF3a-mediated inflammasome activation, as well as key ORF3a amino acid residues needed for virus release and inflammasome activation conserved in the new variants of SARS-CoV-2 isolates across continents, ORF3a and NLRP3 present prime targets for intervention.


Subject(s)
COVID-19/metabolism , COVID-19/virology , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , SARS-CoV-2/physiology , Signal Transduction , Viroporin Proteins/genetics , Amino Acid Sequence , Antiviral Agents/pharmacology , Cell Death , Cell Line , Host-Pathogen Interactions , Humans , Models, Biological , Open Reading Frames , Potassium/metabolism , Signal Transduction/drug effects , Viroporin Proteins/chemistry , Viroporin Proteins/metabolism
6.
Clin Sci (Lond) ; 135(24): 2667-2689, 2021 12 22.
Article in English | MEDLINE | ID: covidwho-1585742

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a broad range of clinical responses including prominent microvascular damage. The capacity of SARS-CoV-2 to infect vascular cells is still debated. Additionally, the SARS-CoV-2 Spike (S) protein may act as a ligand to induce non-infective cellular stress. We tested this hypothesis in pericytes (PCs), which are reportedly reduced in the heart of patients with severe coronavirus disease-2019 (COVID-19). Here we newly show that the in vitro exposure of primary human cardiac PCs to the SARS-CoV-2 wildtype strain or the α and δ variants caused rare infection events. Exposure to the recombinant S protein alone elicited signalling and functional alterations, including: (1) increased migration, (2) reduced ability to support endothelial cell (EC) network formation on Matrigel, (3) secretion of pro-inflammatory molecules typically involved in the cytokine storm, and (4) production of pro-apoptotic factors causing EC death. Next, adopting a blocking strategy against the S protein receptors angiotensin-converting enzyme 2 (ACE2) and CD147, we discovered that the S protein stimulates the phosphorylation/activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) through the CD147 receptor, but not ACE2, in PCs. The neutralisation of CD147, either using a blocking antibody or mRNA silencing, reduced ERK1/2 activation, and rescued PC function in the presence of the S protein. Immunoreactive S protein was detected in the peripheral blood of infected patients. In conclusion, our findings suggest that the S protein may prompt PC dysfunction, potentially contributing to microvascular injury. This mechanism may have clinical and therapeutic implications.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Basigin/metabolism , Myocardium/enzymology , Pericytes/enzymology , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/blood , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/blood , Caco-2 Cells , Cell Death , Child , Child, Preschool , Cytokines/metabolism , Female , Host-Pathogen Interactions , Humans , Infant , Infant, Newborn , Male , Middle Aged , Myocardium/cytology , Pericytes/virology , Primary Cell Culture , Young Adult
7.
Cell Death Dis ; 12(12): 1156, 2021 12 14.
Article in English | MEDLINE | ID: covidwho-1585874

ABSTRACT

Lots of cell death initiator and effector molecules, signalling pathways and subcellular sites have been identified as key mediators in both cell death processes in cancer. The XDeathDB visualization platform provides a comprehensive cell death and their crosstalk resource for deciphering the signaling network organization of interactions among different cell death modes associated with 1461 cancer types and COVID-19, with an aim to understand the molecular mechanisms of physiological cell death in disease and facilitate systems-oriented novel drug discovery in inducing cell deaths properly. Apoptosis, autosis, efferocytosis, ferroptosis, immunogenic cell death, intrinsic apoptosis, lysosomal cell death, mitotic cell death, mitochondrial permeability transition, necroptosis, parthanatos, and pyroptosis related to 12 cell deaths and their crosstalk can be observed systematically by the platform. Big data for cell death gene-disease associations, gene-cell death pathway associations, pathway-cell death mode associations, and cell death-cell death associations is collected by literature review articles and public database from iRefIndex, STRING, BioGRID, Reactom, Pathway's commons, DisGeNET, DrugBank, and Therapeutic Target Database (TTD). An interactive webtool, XDeathDB, is built by web applications with R-Shiny, JavaScript (JS) and Shiny Server Iso. With this platform, users can search specific interactions from vast interdependent networks that occur in the realm of cell death. A multilayer spectral graph clustering method that performs convex layer aggregation to identify crosstalk function among cell death modes for a specific cancer. 147 hallmark genes of cell death could be observed in detail in these networks. These potential druggable targets are displayed systematically and tailoring networks to visualize specified relations is available to fulfil user-specific needs. Users can access XDeathDB for free at https://pcm2019.shinyapps.io/XDeathDB/ .


Subject(s)
Cell Death/physiology , Regulated Cell Death/physiology , Signal Transduction/physiology , Animals , COVID-19/metabolism , COVID-19/physiopathology , Cluster Analysis , Databases, Factual , Humans , Necroptosis , Neoplasms/metabolism , Neoplasms/physiopathology , Phagocytosis , SARS-CoV-2/metabolism , SARS-CoV-2/physiology , Signal Transduction/drug effects , Software
8.
Br J Haematol ; 196(5): 1159-1169, 2022 03.
Article in English | MEDLINE | ID: covidwho-1583669

ABSTRACT

COVID-19 has compelled scientists to better describe its pathophysiology to find new therapeutic approaches. While risk factors, such as older age, obesity, and diabetes mellitus, suggest a central role of endothelial cells (ECs), autopsies have revealed clots in the pulmonary microvasculature that are rich in neutrophils and DNA traps produced by these cells, called neutrophil extracellular traps (NETs.) Submicron extracellular vesicles, called microparticles (MPs), are described in several diseases as being involved in pro-inflammatory pathways. Therefore, in this study, we analyzed three patient groups: one for which intubation was not necessary, an intubated group, and one group after extubation. In the most severe group, the intubated group, platelet-derived MPs and endothelial cell (EC)-derived MPs exhibited increased concentration and size, when compared to uninfected controls. MPs of intubated COVID-19 patients triggered EC death and overexpression of two adhesion molecules: P-selectin and vascular cell adhesion molecule-1 (VCAM-1). Strikingly, neutrophil adhesion and NET production were increased following incubation with these ECs. Importantly, we also found that preincubation of these COVID-19 MPs with the phosphatidylserine capping endogenous protein, annexin A5, abolished cytotoxicity, P-selectin and VCAM-1 induction, all like increases in neutrophil adhesion and NET release. Taken together, our results reveal that MPs play a key role in COVID-19 pathophysiology and point to a potential therapeutic: annexin A5.


Subject(s)
COVID-19/immunology , Cell-Derived Microparticles/immunology , Endothelial Cells/immunology , Neutrophils/immunology , SARS-CoV-2/immunology , COVID-19/pathology , COVID-19/therapy , Cell Adhesion , Cell Death , Cell-Derived Microparticles/pathology , Cells, Cultured , Endothelial Cells/pathology , Extracellular Traps/immunology , Humans , Inflammation/immunology , Inflammation/pathology , Intubation , Neutrophils/pathology , Phosphatidylserines/immunology
9.
Viruses ; 13(12)2021 12 14.
Article in English | MEDLINE | ID: covidwho-1572670

ABSTRACT

SARS-CoV-2 is a new type of coronavirus that has caused worldwide pandemic. The disease induced by SARS-CoV-2 is called COVID-19. A majority of people with COVID-19 have relatively mild respiratory symptoms. However, a small percentage of COVID-19 patients develop a severe disease where multiple organs are affected. These severe forms of SARS-CoV-2 infections are associated with excessive production of pro-inflammatory cytokines, so called "cytokine storm". Inflammasomes, which are protein complexes of the innate immune system orchestrate development of local and systemic inflammation during virus infection. Recent data suggest involvement of inflammasomes in severe COVID-19. Activation of inflammasome exerts two major effects: it activates caspase-1-mediated processing and secretion of pro-inflammatory cytokines IL-1ß and IL-18, and induces inflammatory cell death, pyroptosis, via protein called gasdermin D. Here, we provide comprehensive review of current understanding of the activation and possible functions of different inflammasome structures during SARS-CoV-2 infection and compare that to response caused by influenza A virus. We also discuss how novel SARS-CoV-2 mRNA vaccines activate innate immune response, which is a prerequisite for the activation of protective adaptive immune response.


Subject(s)
COVID-19/immunology , Inflammasomes/immunology , Adaptive Immunity , COVID-19 Vaccines , Cell Death , Cytokine Release Syndrome , Cytokines/immunology , Humans , Immunity, Innate , Inflammation , Interleukin-18 , Interleukin-1beta , Neoplasm Proteins , Pyroptosis , SARS-CoV-2/immunology
10.
Molecules ; 26(24)2021 Dec 09.
Article in English | MEDLINE | ID: covidwho-1572567

ABSTRACT

COVID-19 is the name of the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection that occurred in 2019. The virus-host-specific interactions, molecular targets on host cell deaths, and the involved signaling are crucial issues, which become potential targets for treatment. Spike protein, angiotensin-converting enzyme 2 (ACE2), cathepsin L-cysteine peptidase, transmembrane protease serine 2 (TMPRSS2), nonstructural protein 1 (Nsp1), open reading frame 7a (ORF7a), viral main protease (3C-like protease (3CLpro) or Mpro), RNA dependent RNA polymerase (RdRp) (Nsp12), non-structural protein 13 (Nsp13) helicase, and papain-like proteinase (PLpro) are molecules associated with SARS-CoV infection and propagation. SARS-CoV-2 can induce host cell death via five kinds of regulated cell death, i.e., apoptosis, necroptosis, pyroptosis, autophagy, and PANoptosis. The mechanisms of these cell deaths are well established and can be disrupted by synthetic small molecules or natural products. There are a variety of compounds proven to play roles in the cell death inhibition, such as pan-caspase inhibitor (z-VAD-fmk) for apoptosis, necrostatin-1 for necroptosis, MCC950, a potent and specific inhibitor of the NLRP3 inflammasome in pyroptosis, and chloroquine/hydroxychloroquine, which can mitigate the corresponding cell death pathways. However, NF-κB signaling is another critical anti-apoptotic or survival route mediated by SARS-CoV-2. Such signaling promotes viral survival, proliferation, and inflammation by inducing the expression of apoptosis inhibitors such as Bcl-2 and XIAP, as well as cytokines, e.g., TNF. As a result, tiny natural compounds functioning as proteasome inhibitors such as celastrol and curcumin can be used to modify NF-κB signaling, providing a responsible method for treating SARS-CoV-2-infected patients. The natural constituents that aid in inhibiting viral infection, progression, and amplification of coronaviruses are also emphasized, which are in the groups of alkaloids, flavonoids, terpenoids, diarylheptanoids, and anthraquinones. Natural constituents derived from medicinal herbs have anti-inflammatory and antiviral properties, as well as inhibitory effects, on the viral life cycle, including viral entry, replication, assembly, and release of COVID-19 virions. The phytochemicals contain a high potential for COVID-19 treatment. As a result, SARS-CoV-2-infected cell death processes and signaling might be of high efficacy for therapeutic targeting effects and yielding encouraging outcomes.


Subject(s)
COVID-19/drug therapy , Cell Death/drug effects , Drug Discovery/methods , Molecular Targeted Therapy/methods , SARS-CoV-2/drug effects , Amino Acid Chloromethyl Ketones/pharmacology , Antiviral Agents/pharmacology , Apoptosis/drug effects , Furans/pharmacology , Humans , Hydroxychloroquine/pharmacology , Imidazoles/pharmacology , Indenes/pharmacology , Indoles/pharmacology , Necroptosis/drug effects , Phytochemicals/pharmacology , Pyroptosis/drug effects , SARS-CoV-2/metabolism , Signal Transduction/drug effects , Sulfonamides/pharmacology , Viral Proteins/antagonists & inhibitors
11.
Int J Mol Sci ; 22(24)2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1572496

ABSTRACT

In humans, over-activation of innate immunity in response to viral or bacterial infections often causes severe illness and death. Furthermore, similar mechanisms related to innate immunity can cause pathogenesis and death in sepsis, massive trauma (including surgery and burns), ischemia/reperfusion, some toxic lesions, and viral infections including COVID-19. Based on the reviewed observations, we suggest that such severe outcomes may be manifestations of a controlled suicidal strategy protecting the entire population from the spread of pathogens and from dangerous pathologies rather than an aberrant hyperstimulation of defense responses. We argue that innate immunity may be involved in the implementation of an altruistic programmed death of an organism aimed at increasing the well-being of the whole community. We discuss possible ways to suppress this atavistic program by interfering with innate immunity and suggest that combating this program should be a major goal of future medicine.


Subject(s)
Altruism , Apoptosis/immunology , Immunity, Innate/immunology , Animals , COVID-19/immunology , Cell Death/immunology , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/mortality , Humans , Inflammasomes/immunology , Inflammation/immunology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Signal Transduction/immunology
12.
Free Radic Res ; 55(9-10): 982-995, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1555313

ABSTRACT

The inflammation and activation of the immune system induced by SARS-CoV-2 are mediated by a pro-oxidant microenvironment that can induce cytotoxic effects that enhance tissue damage, favoring organic deterioration. We investigated whether the induction of oxidative stress and inflammation by COVID-19 infection could inhibit mitochondrial function and cause cellular damage in leukocytes. We evaluated levels of oxidative/inflammation markers and their correlation with mitochondrial function and leukocyte cell death in COVID-19 patients at two moments: viremia and severe sepsis with multi-organ failure. COVID-19 induces increased oxidative stress and inflammation markers that activate cellular damage processes. In the viremia stage, an increase in peroxide, nitric oxide, carbonylated proteins, and IL-6 was observed, which was correlated with a marked inhibition of mitochondrial function, decreased cell viability, early apoptosis, necrosis, and leukocytes-reactivity. The severe sepsis stage with multi-organ failure also showed a further increase in levels of peroxide, carbonylated proteins, and IL-6, with a slight decrease in nitric oxide. This oxidative process and inflammation were correlated with less inhibition of mitochondrial function, decreased cell viability and an increase in late apoptosis, and morphology changes evidencing damage in the leukocytes. SARS-CoV-2 induced damage promotes levels of oxidative stress and inflammation markers and mitochondrial dysfunction that potentiate morphological changes and cell death in leukocytes. These processes explain the rapid changes in the immune system, and that present an initial over-activation and early massive death due to SARS-CoV-2 infection, promoting endothelial-alveolar damage that would cause multi-organ failure, sustained by oxidative stress and inflammation.


Subject(s)
COVID-19 , Cell Death , Humans , Inflammation , Leukocytes , Mitochondria , Oxidative Stress , SARS-CoV-2
13.
Clin Sci (Lond) ; 135(24): 2667-2689, 2021 12 22.
Article in English | MEDLINE | ID: covidwho-1528037

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a broad range of clinical responses including prominent microvascular damage. The capacity of SARS-CoV-2 to infect vascular cells is still debated. Additionally, the SARS-CoV-2 Spike (S) protein may act as a ligand to induce non-infective cellular stress. We tested this hypothesis in pericytes (PCs), which are reportedly reduced in the heart of patients with severe coronavirus disease-2019 (COVID-19). Here we newly show that the in vitro exposure of primary human cardiac PCs to the SARS-CoV-2 wildtype strain or the α and δ variants caused rare infection events. Exposure to the recombinant S protein alone elicited signalling and functional alterations, including: (1) increased migration, (2) reduced ability to support endothelial cell (EC) network formation on Matrigel, (3) secretion of pro-inflammatory molecules typically involved in the cytokine storm, and (4) production of pro-apoptotic factors causing EC death. Next, adopting a blocking strategy against the S protein receptors angiotensin-converting enzyme 2 (ACE2) and CD147, we discovered that the S protein stimulates the phosphorylation/activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) through the CD147 receptor, but not ACE2, in PCs. The neutralisation of CD147, either using a blocking antibody or mRNA silencing, reduced ERK1/2 activation, and rescued PC function in the presence of the S protein. Immunoreactive S protein was detected in the peripheral blood of infected patients. In conclusion, our findings suggest that the S protein may prompt PC dysfunction, potentially contributing to microvascular injury. This mechanism may have clinical and therapeutic implications.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Basigin/metabolism , Myocardium/enzymology , Pericytes/enzymology , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/blood , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/blood , Caco-2 Cells , Cell Death , Child , Child, Preschool , Cytokines/metabolism , Female , Host-Pathogen Interactions , Humans , Infant , Infant, Newborn , Male , Middle Aged , Myocardium/cytology , Pericytes/virology , Primary Cell Culture , Young Adult
14.
Clin Transl Sci ; 14(6): 2348-2359, 2021 11.
Article in English | MEDLINE | ID: covidwho-1526356

ABSTRACT

Coronavirus disease 2019 (COVID-19) global pandemic is caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) viral infection, which can lead to pneumonia, lung injury, and death in susceptible populations. Understanding viral dynamics of SARS-CoV-2 is critical for development of effective treatments. An Immune-Viral Dynamics Model (IVDM) is developed to describe SARS-CoV-2 viral dynamics and COVID-19 disease progression. A dataset of 60 individual patients with COVID-19 with clinical viral load (VL) and reported disease severity were assembled from literature. Viral infection and replication mechanisms of SARS-CoV-2, viral-induced cell death, and time-dependent immune response are incorporated in the model to describe the dynamics of viruses and immune response. Disease severity are tested as a covariate to model parameters. The IVDM was fitted to the data and parameters were estimated using the nonlinear mixed-effect model. The model can adequately describe individual viral dynamics profiles, with disease severity identified as a covariate on infected cell death rate. The modeling suggested that it takes about 32.6 days to reach 50% of maximum cell-based immunity. Simulations based on virtual populations suggested a typical mild case reaches VL limit of detection (LOD) by 13 days with no treatment, a moderate case by 17 days, and a severe case by 41 days. Simulations were used to explore hypothetical treatments with different initiation time, disease severity, and drug effects to demonstrate the usefulness of such modeling in informing decisions. Overall, the IVDM modeling and simulation platform enables simulations for viral dynamics and treatment efficacy and can be used to aid in clinical pharmacokinetic/pharmacodynamic (PK/PD) and dose-efficacy response analysis for COVID-19 drug development.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/drug therapy , Drug Development/methods , Host Microbial Interactions/immunology , Models, Biological , Antiviral Agents/therapeutic use , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , Cell Death/drug effects , Cell Death/immunology , Datasets as Topic , Dose-Response Relationship, Drug , Host Microbial Interactions/drug effects , Humans , Nonlinear Dynamics , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Severity of Illness Index , Treatment Outcome , Viral Load
15.
PLoS One ; 16(10): e0258292, 2021.
Article in English | MEDLINE | ID: covidwho-1480450

ABSTRACT

Chagas disease is a neglected illness caused by Trypanosoma cruzi and its treatment is done only with two drugs, nifurtimox and benznidazole. However, both drugs are ineffective in the chronic phase, in addition to causing serious side effects. This context of therapeutic limitation justifies the continuous research for alternative drugs. Here, we study the in vitro trypanocidal effects of the non-steroidal anti-inflammatory drug nimesulide, a molecule that has in its chemical structure a toxicophoric nitroaromatic group (NO2). The set of results obtained in this work highlights the potential for repurposing nimesulide in the treatment of this disease that affects millions of people around the world.


Subject(s)
Chagas Disease/drug therapy , Chagas Disease/parasitology , Drug Repositioning , Sulfonamides/therapeutic use , Trypanosoma cruzi/physiology , Animals , Cell Death/drug effects , Cell Survival/drug effects , Life Cycle Stages/drug effects , Mice, Inbred BALB C , Parasites/drug effects , Sulfonamides/chemistry , Sulfonamides/pharmacology , Trypanosoma cruzi/drug effects , Trypanosoma cruzi/growth & development , Trypanosoma cruzi/ultrastructure
16.
J Clin Invest ; 131(20)2021 10 15.
Article in English | MEDLINE | ID: covidwho-1470547

ABSTRACT

BACKGROUNDMultisystem inflammatory syndrome in children (MIS-C) is a rare but potentially severe illness that follows exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Kawasaki disease (KD) shares several clinical features with MIS-C, which prompted the use of intravenous immunoglobulin (IVIG), a mainstay therapy for KD. Both diseases share a robust activation of the innate immune system, including the IL-1 signaling pathway, and IL-1 blockade has been used for the treatment of both MIS-C and KD. The mechanism of action of IVIG in these 2 diseases and the cellular source of IL-1ß have not been defined.METHODSThe effects of IVIG on peripheral blood leukocyte populations from patients with MIS-C and KD were examined using flow cytometry and mass cytometry (CyTOF) and live-cell imaging.RESULTSCirculating neutrophils were highly activated in patients with KD and MIS-C and were a major source of IL-1ß. Following IVIG treatment, activated IL-1ß+ neutrophils were reduced in the circulation. In vitro, IVIG was a potent activator of neutrophil cell death via PI3K and NADPH oxidase, but independently of caspase activation.CONCLUSIONSActivated neutrophils expressing IL-1ß can be targeted by IVIG, supporting its use in both KD and MIS-C to ameliorate inflammation.FUNDINGPatient Centered Outcomes Research Institute; NIH; American Asthma Foundation; American Heart Association; Novo Nordisk Foundation; NIGMS; American Academy of Allergy, Asthma and Immunology Foundation.


Subject(s)
COVID-19/complications , Immunoglobulins, Intravenous/therapeutic use , Mucocutaneous Lymph Node Syndrome/immunology , Mucocutaneous Lymph Node Syndrome/therapy , Systemic Inflammatory Response Syndrome/immunology , Systemic Inflammatory Response Syndrome/therapy , COVID-19/blood , COVID-19/immunology , COVID-19/therapy , Case-Control Studies , Cell Death/immunology , Cell Lineage/immunology , Child , Child, Preschool , Fas Ligand Protein/immunology , Female , Humans , Infant , Interleukin-1beta/antagonists & inhibitors , Interleukin-1beta/blood , Leukocyte Count , Male , Mucocutaneous Lymph Node Syndrome/blood , Neutrophil Activation , Neutrophils/classification , Neutrophils/immunology , Neutrophils/pathology , Systemic Inflammatory Response Syndrome/blood
17.
Free Radic Biol Med ; 177: 189-200, 2021 12.
Article in English | MEDLINE | ID: covidwho-1466351

ABSTRACT

As hypoxia is a major driver for the pathophysiology of COVID-19, it is crucial to characterize the hypoxic response at the cellular and molecular levels. In order to augment drug repurposing with the identification of appropriate molecular targets, investigations on therapeutics preventing hypoxic cell damage is required. In this work, we propose a hypoxia model based on alveolar lung epithelial cells line using chemical inducer, CoCl2 that can be used for testing calcium channel blockers (CCBs). Since recent studies suggested that CCBs may reduce the infectivity of SARS-Cov-2, we specifically select FDA approved calcium channel blocker, nifedipine for the study. First, we examined hypoxia-induced cell morphology and found a significant increase in cytosolic calcium levels, mitochondrial calcium overload as well as ROS production in hypoxic A549 cells. Secondly, we demonstrate the protective behaviour of nifedipine for cells that are already subjected to hypoxia through measurement of cell viability as well as 4D imaging of cellular morphology and nuclear condensation. Thirdly, we show that the protective effect of nifedipine is achieved through the reduction of cytosolic calcium, mitochondrial calcium, and ROS generation. Overall, we outline a framework for quantitative analysis of mitochondrial calcium and ROS using 3D imaging in laser scanning confocal microscopy and the open-source image analysis platform ImageJ. The proposed pipeline was used to visualize mitochondrial calcium and ROS level in individual cells that provide an understanding of molecular targets. Our findings suggest that the therapeutic value of nifedipine may potentially be evaluated in the context of COVID-19 therapeutic trials.


Subject(s)
COVID-19 , Nifedipine , A549 Cells , Calcium , Calcium Channel Blockers/pharmacology , Calcium Channel Blockers/therapeutic use , Cell Death , Humans , Hypoxia/drug therapy , Nifedipine/pharmacology , SARS-CoV-2 , Superoxides
18.
Cells ; 10(10)2021 10 05.
Article in English | MEDLINE | ID: covidwho-1458308

ABSTRACT

Extracellular vesicles (EVs) have been identified as novel mediators of intercellular communication. They work via delivering the sequestered cargo to cells in the close vicinity, as well as distant sites in the body, regulating pathophysiological processes. Cell death and inflammation are biologically crucial processes in both normal physiology and pathology. These processes are indistinguishably linked with their effectors modulating the other process. For instance, during an unresolvable infection, the upregulation of specific immune mediators leads to inflammation causing cell death and tissue damage. EVs have gained considerable interest as mediators of both cell death and inflammation during conditions, such as sepsis. This review summarizes the types of extracellular vesicles known to date and their roles in mediating immune responses leading to cell death and inflammation with specific focus on sepsis and lung inflammation.


Subject(s)
Apoptosis , COVID-19/therapy , Cell Death , Extracellular Vesicles/metabolism , Inflammation/metabolism , Lung/pathology , SARS-CoV-2 , Sepsis/immunology , Animals , Biomarkers/metabolism , COVID-19/immunology , Cell Communication , Chemokines , Exosomes , Humans , Lung/immunology , Mice , Sepsis/physiopathology
19.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Article in English | MEDLINE | ID: covidwho-1450313

ABSTRACT

Cancer therapy reduces tumor burden via tumor cell death ("debris"), which can accelerate tumor progression via the failure of inflammation resolution. Thus, there is an urgent need to develop treatment modalities that stimulate the clearance or resolution of inflammation-associated debris. Here, we demonstrate that chemotherapy-generated debris stimulates metastasis by up-regulating soluble epoxide hydrolase (sEH) and the prostaglandin E2 receptor 4 (EP4). Therapy-induced tumor cell debris triggers a storm of proinflammatory and proangiogenic eicosanoid-driven cytokines. Thus, targeting a single eicosanoid or cytokine is unlikely to prevent chemotherapy-induced metastasis. Pharmacological abrogation of both sEH and EP4 eicosanoid pathways prevents hepato-pancreatic tumor growth and liver metastasis by promoting macrophage phagocytosis of debris and counterregulating a protumorigenic eicosanoid and cytokine storm. Therefore, stimulating the clearance of tumor cell debris via combined sEH and EP4 inhibition is an approach to prevent debris-stimulated metastasis and tumor growth.


Subject(s)
Eicosanoids/metabolism , Epoxide Hydrolases/biosynthesis , Macrophages/immunology , Neoplasm Metastasis/pathology , Receptors, Prostaglandin E, EP4 Subtype/biosynthesis , Animals , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/pathology , Cell Death/drug effects , Cell Line, Tumor , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/prevention & control , Cytokines/metabolism , Hep G2 Cells , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Male , Mice , Mice, Inbred C57BL , Neoplasm Metastasis/prevention & control , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Phagocytosis/immunology , RAW 264.7 Cells
20.
Cell Host Microbe ; 28(6): 853-866.e5, 2020 12 09.
Article in English | MEDLINE | ID: covidwho-1385263

ABSTRACT

Pathogenesis induced by SARS-CoV-2 is thought to result from both an inflammation-dominated cytokine response and virus-induced cell perturbation causing cell death. Here, we employ an integrative imaging analysis to determine morphological organelle alterations induced in SARS-CoV-2-infected human lung epithelial cells. We report 3D electron microscopy reconstructions of whole cells and subcellular compartments, revealing extensive fragmentation of the Golgi apparatus, alteration of the mitochondrial network and recruitment of peroxisomes to viral replication organelles formed by clusters of double-membrane vesicles (DMVs). These are tethered to the endoplasmic reticulum, providing insights into DMV biogenesis and spatial coordination of SARS-CoV-2 replication. Live cell imaging combined with an infection sensor reveals profound remodeling of cytoskeleton elements. Pharmacological inhibition of their dynamics suppresses SARS-CoV-2 replication. We thus report insights into virus-induced cytopathic effects and provide alongside a comprehensive publicly available repository of 3D datasets of SARS-CoV-2-infected cells for download and smooth online visualization.


Subject(s)
COVID-19/genetics , Endoplasmic Reticulum/ultrastructure , SARS-CoV-2/ultrastructure , Viral Replication Compartments/ultrastructure , COVID-19/diagnostic imaging , COVID-19/pathology , COVID-19/virology , Cell Death/genetics , Endoplasmic Reticulum/genetics , Endoplasmic Reticulum/virology , Humans , Microscopy, Electron , Pandemics , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Viral Replication Compartments/metabolism , Virus Replication/genetics
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