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3.
Ann Intern Med ; 174(1): JC2, 2021 01.
Article in English | MEDLINE | ID: covidwho-1526979

ABSTRACT

SOURCE CITATION: Lamontagne F, Agoritsas T, Macdonald H, et al. A living WHO guideline on drugs for covid-19. BMJ. 2020;370:m3379. 32887691.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , COVID-19/drug therapy , Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , Practice Guidelines as Topic , Betacoronavirus , Critical Illness , Humans , Pandemics , SARS-CoV-2 , World Health Organization
4.
JAMA ; 326(17): 1703-1712, 2021 11 02.
Article in English | MEDLINE | ID: covidwho-1525396

ABSTRACT

Importance: Acutely ill inpatients with COVID-19 typically receive antithrombotic therapy, although the risks and benefits of this intervention among outpatients with COVID-19 have not been established. Objective: To assess whether anticoagulant or antiplatelet therapy can safely reduce major adverse cardiopulmonary outcomes among symptomatic but clinically stable outpatients with COVID-19. Design, Setting, and Participants: The ACTIV-4B Outpatient Thrombosis Prevention Trial was designed as a minimal-contact, adaptive, randomized, double-blind, placebo-controlled trial to compare anticoagulant and antiplatelet therapy among 7000 symptomatic but clinically stable outpatients with COVID-19. The trial was conducted at 52 US sites between September 2020 and June 2021; final follow-up was August 5, 2021. Prior to initiating treatment, participants were required to have platelet count greater than 100 000/mm3 and estimated glomerular filtration rate greater than 30 mL/min/1.73 m2. Interventions: Random allocation in a 1:1:1:1 ratio to aspirin (81 mg orally once daily; n = 164), prophylactic-dose apixaban (2.5 mg orally twice daily; n = 165), therapeutic-dose apixaban (5 mg orally twice daily; n = 164), or placebo (n = 164) for 45 days. Main Outcomes and Measures: The primary end point was a composite of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary cause. The primary analyses for efficacy and bleeding events were limited to participants who took at least 1 dose of trial medication. Results: On June 18, 2021, the trial data and safety monitoring board recommended early termination because of lower than anticipated event rates; at that time, 657 symptomatic outpatients with COVID-19 had been randomized (median age, 54 years [IQR, 46-59]; 59% women). The median times from diagnosis to randomization and from randomization to initiation of study treatment were 7 days and 3 days, respectively. Twenty-two randomized participants (3.3%) were hospitalized for COVID-19 prior to initiating treatment. Among the 558 patients who initiated treatment, the adjudicated primary composite end point occurred in 1 patient (0.7%) in the aspirin group, 1 patient (0.7%) in the 2.5-mg apixaban group, 2 patients (1.4%) in the 5-mg apixaban group, and 1 patient (0.7%) in the placebo group. The risk differences compared with placebo for the primary end point were 0.0% (95% CI not calculable) in the aspirin group, 0.7% (95% CI, -2.1% to 4.1%) in the 2.5-mg apixaban group, and 1.4% (95% CI, -1.5% to 5.0%) in the 5-mg apixaban group. Risk differences compared with placebo for bleeding events were 2.0% (95% CI, -2.7% to 6.8%), 4.5% (95% CI, -0.7% to 10.2%), and 6.9% (95% CI, 1.4% to 12.9%) among participants who initiated therapy in the aspirin, prophylactic apixaban, and therapeutic apixaban groups, respectively, although none were major. Findings inclusive of all randomized patients were similar. Conclusions and Relevance: Among symptomatic clinically stable outpatients with COVID-19, treatment with aspirin or apixaban compared with placebo did not reduce the rate of a composite clinical outcome. However, the study was terminated after enrollment of 9% of participants because of an event rate lower than anticipated. Trial Registration: ClinicalTrials.gov Identifier: NCT04498273.


Subject(s)
Aspirin/therapeutic use , COVID-19/drug therapy , Factor Xa Inhibitors/therapeutic use , Platelet Aggregation Inhibitors/therapeutic use , Pyrazoles/therapeutic use , Pyridones/therapeutic use , Thrombosis/prevention & control , Adult , Aspirin/adverse effects , COVID-19/complications , Dose-Response Relationship, Drug , Double-Blind Method , Early Termination of Clinical Trials , Factor Xa Inhibitors/administration & dosage , Factor Xa Inhibitors/adverse effects , Female , Hemorrhage/chemically induced , Hospitalization , Humans , Male , Middle Aged , Platelet Aggregation Inhibitors/adverse effects , Pyrazoles/administration & dosage , Pyrazoles/adverse effects , Pyridones/administration & dosage , Pyridones/adverse effects
5.
Molecules ; 26(20)2021 Oct 13.
Article in English | MEDLINE | ID: covidwho-1526851

ABSTRACT

There have been more than 150 million confirmed cases of SARS-CoV-2 since the beginning of the pandemic in 2019. By June 2021, the mortality from such infections approached 3.9 million people. Despite the availability of a number of vaccines which provide protection against this virus, the evolution of new viral variants, inconsistent availability of the vaccine around the world, and vaccine hesitancy, in some countries, makes it unreasonable to rely on mass vaccination alone to combat this pandemic. Consequently, much effort is directed to identifying potential antiviral treatments. Marine brominated tyrosine alkaloids are recognized to have antiviral potential. We test here the antiviral capacity of fourteen marine brominated tyrosine alkaloids against five different target proteins from SARS-CoV-2, including main protease (Mpro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H). These marine alkaloids, particularly the hexabrominated compound, fistularin-3, shows promising docking interactions with predicted binding affinities (S-score = -7.78, -7.65, -6.39, -6.28, -8.84 Kcal/mol) for the main protease (Mpro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H), respectively, where it forms better interactions with the protein pockets than the native interaction. It also shows promising molecular dynamics, pharmacokinetics, and toxicity profiles. As such, further exploration of the antiviral properties of fistularin-3 against SARS-CoV-2 is merited.


Subject(s)
Alkaloids/chemistry , SARS-CoV-2/metabolism , Alkaloids/isolation & purification , Alkaloids/therapeutic use , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/therapeutic use , Binding Sites , COVID-19/drug therapy , COVID-19/virology , Coronavirus 3C Proteases/chemistry , Coronavirus 3C Proteases/metabolism , Halogenation , Humans , Isoxazoles/chemistry , Isoxazoles/metabolism , Molecular Docking Simulation , Molecular Dynamics Simulation , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Structure-Activity Relationship , Tyrosine/analogs & derivatives , Tyrosine/chemistry , Tyrosine/metabolism
6.
Cell Rep ; 37(4): 109882, 2021 10 26.
Article in English | MEDLINE | ID: covidwho-1525720

ABSTRACT

Remdesivir (RDV), a nucleotide analog with broad-spectrum features, has exhibited effectiveness in COVID-19 treatment. However, the precise working mechanism of RDV when targeting the viral RNA-dependent RNA polymerase (RdRP) has not been fully elucidated. Here, we solve a 3.0-Å structure of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RdRP elongation complex (EC) and assess RDV intervention in polymerase elongation phase. Although RDV could induce an "i+3" delayed termination in meta-stable complexes, only pausing and subsequent elongation are observed in the EC. A comparative investigation using an enterovirus RdRP further confirms similar delayed intervention and demonstrates that steric hindrance of the RDV-characteristic 1'-cyano at the -4 position is responsible for the "i+3" intervention, although two representative Flaviviridae RdRPs do not exhibit similar behavior. A comparison of representative viral RdRP catalytic complex structures indicates that the product RNA backbone encounters highly conserved structural elements, highlighting the broad-spectrum intervention potential of 1'-modified nucleotide analogs in anti-RNA virus drug development.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , RNA-Dependent RNA Polymerase/drug effects , SARS-CoV-2/drug effects , Viral Proteins/drug effects , Adenosine Monophosphate/pharmacology , Alanine/pharmacology , COVID-19/drug therapy , Cryoelectron Microscopy , Humans , RNA, Viral/chemistry , RNA, Viral/drug effects , RNA-Dependent RNA Polymerase/chemistry , SARS-CoV-2/chemistry , Viral Proteins/chemistry , Virus Replication/drug effects
7.
mBio ; 12(2)2021 03 30.
Article in English | MEDLINE | ID: covidwho-1522913

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a recently emerged virus that causes coronavirus infectious disease 2019 (COVID-19). SARS-CoV-2 spike protein, like SARS-CoV-1, uses the angiotensin converting enzyme 2 (ACE2) as a cellular receptor to initiate infection. Compounds that interfere with the SARS-CoV-2 spike protein receptor binding domain protein (RBD)-ACE2 receptor interaction may function as entry inhibitors. Here, we used a dual strategy of molecular docking and surface plasmon resonance (SPR) screening of compound libraries to identify those that bind to human ACE2 or the SARS-CoV-2 spike protein receptor binding domain (RBD). Molecular modeling screening interrogated 57,641 compounds and focused on the region of ACE2 that is engaged by RBD of the SARS-CoV-2 spike glycoprotein and vice versa. SPR screening used immobilized human ACE2 and SARS-CoV-2 Spike protein to evaluate the binding of these proteins to a library of 3,141 compounds. These combined screens identified compounds from these libraries that bind at KD (equilibrium dissociation constant) <3 µM affinity to their respective targets, 17 for ACE2 and 6 for SARS-CoV-2 RBD. Twelve ACE2 binders and six of the RBD binders compete with the RBD-ACE2 interaction in an SPR-based competition assay. These compounds included registered drugs and dyes used in biomedical applications. A Vero-E6 cell-based SARS-CoV-2 infection assay was used to evaluate infection blockade by candidate entry inhibitors. Three compounds demonstrated dose-dependent antiviral in vitro potency-Evans blue, sodium lifitegrast, and lumacaftor. This study has identified potential drugs for repurposing as SARS-CoV-2 entry inhibitors or as chemical scaffolds for drug development.IMPORTANCE SARS-CoV-2, the causative agent of COVID-19, has caused more than 60 million cases worldwide with almost 1.5 million deaths as of November 2020. Repurposing existing drugs is the most rapid path to clinical intervention for emerging diseases. Using an in silico screen of 57,641 compounds and a biophysical screen of 3,141 compounds, we identified 22 compounds that bound to either the angiotensin converting enzyme 2 (ACE2) and/or the SARS-CoV-2 spike protein receptor binding domain (SARS-CoV-2 spike protein RBD). Nine of these drugs were identified by both screening methods. Three of the identified compounds, Evans blue, sodium lifitegrast, and lumacaftor, were found to inhibit viral replication in a Vero-E6 cell-based SARS-CoV-2 infection assay and may have utility as repurposed therapeutics. All 22 identified compounds provide scaffolds for the development of new chemical entities for the treatment of COVID-19.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/pharmacology , COVID-19/drug therapy , Spike Glycoprotein, Coronavirus/metabolism , Virus Attachment/drug effects , Virus Replication/drug effects , Aminopyridines/pharmacology , Animals , Benzodioxoles/pharmacology , Cell Line , Chlorocebus aethiops , Drug Evaluation, Preclinical , Drug Repositioning , Evans Blue/pharmacology , Humans , Molecular Docking Simulation , Phenylalanine/analogs & derivatives , Phenylalanine/pharmacology , Protein Binding/drug effects , SARS-CoV-2/drug effects , SARS-CoV-2/physiology , Sulfones/pharmacology , Surface Plasmon Resonance , Vero Cells
9.
Ann Intern Med ; 174(1): JC3, 2021 01.
Article in English | MEDLINE | ID: covidwho-1518748

ABSTRACT

SOURCE CITATION: RECOVERY Collaborative Group. Lopinavir-ritonavir in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial. Lancet. 2020;396:1345-52. 33031764.


Subject(s)
Antiviral Agents/therapeutic use , COVID-19/drug therapy , Hospitalization , Lopinavir/therapeutic use , Ritonavir/therapeutic use , Administration, Oral , Aged , Antiviral Agents/administration & dosage , COVID-19/mortality , Drug Combinations , Female , Humans , Lopinavir/administration & dosage , Male , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Ritonavir/administration & dosage , SARS-CoV-2 , United Kingdom
10.
Molecules ; 26(20)2021 Oct 12.
Article in English | MEDLINE | ID: covidwho-1518621

ABSTRACT

In continuation of our previous effort, different in silico selection methods were applied to 310 naturally isolated metabolites that exhibited antiviral potentialities before. The applied selection methods aimed to pick the most relevant inhibitor of SARS-CoV-2 nsp10. At first, a structural similarity study against the co-crystallized ligand, S-Adenosyl Methionine (SAM), of SARS-CoV-2 nonstructural protein (nsp10) (PDB ID: 6W4H) was carried out. The similarity analysis culled 30 candidates. Secondly, a fingerprint study against SAM preferred compounds 44, 48, 85, 102, 105, 182, 220, 221, 282, 284, 285, 301, and 302. The docking studies picked 48, 182, 220, 221, and 284. While the ADMET analysis expected the likeness of the five candidates to be drugs, the toxicity study preferred compounds 48 and 182. Finally, a density-functional theory (DFT) study suggested vidarabine (182) to be the most relevant SARS-Cov-2 nsp10 inhibitor.


Subject(s)
Antiviral Agents/chemistry , Biological Products/chemistry , SARS-CoV-2/metabolism , Viral Regulatory and Accessory Proteins/antagonists & inhibitors , Antiviral Agents/metabolism , Antiviral Agents/therapeutic use , Binding Sites , Biological Products/metabolism , Biological Products/therapeutic use , COVID-19/drug therapy , COVID-19/pathology , Density Functional Theory , Humans , Ligands , Molecular Docking Simulation , S-Adenosylmethionine/chemistry , S-Adenosylmethionine/metabolism , SARS-CoV-2/isolation & purification , Small Molecule Libraries/chemistry , Small Molecule Libraries/metabolism , Small Molecule Libraries/therapeutic use , Vidarabine/chemistry , Vidarabine/metabolism , Vidarabine/therapeutic use , Viral Regulatory and Accessory Proteins/metabolism
11.
Front Immunol ; 12: 754127, 2021.
Article in English | MEDLINE | ID: covidwho-1518487

ABSTRACT

COVID-19 presentations range from mild to moderate through severe disease but also manifest with persistent illness or viral recrudescence. We hypothesized that the spectrum of COVID-19 disease manifestations was a consequence of SARS-CoV-2-mediated delay in the pathogen-associated molecular pattern (PAMP) response, including dampened type I interferon signaling, thereby shifting the balance of the immune response to be dominated by damage-associated molecular pattern (DAMP) signaling. To test the hypothesis, we constructed a parsimonious mechanistic mathematical model. After calibration of the model for initial viral load and then by varying a few key parameters, we show that the core model generates four distinct viral load, immune response and associated disease trajectories termed "patient archetypes", whose temporal dynamics are reflected in clinical data from hospitalized COVID-19 patients. The model also accounts for responses to corticosteroid therapy and predicts that vaccine-induced neutralizing antibodies and cellular memory will be protective, including from severe COVID-19 disease. This generalizable modeling framework could be used to analyze protective and pathogenic immune responses to diverse viral infections.


Subject(s)
Alarmins/immunology , COVID-19 , Models, Biological , SARS-CoV-2 , Adrenal Cortex Hormones/therapeutic use , Adult , Aged , Anti-Inflammatory Agents/therapeutic use , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/diagnosis , COVID-19/drug therapy , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines , Humans , Middle Aged , Reproducibility of Results , Viral Load
12.
Trials ; 22(1): 808, 2021 Nov 15.
Article in English | MEDLINE | ID: covidwho-1518287

ABSTRACT

BACKGROUND: Pre-exposure prophylaxis (PrEP) is a promising strategy to break COVID-19 transmission. Although hydroxychloroquine was evaluated for treatment and post-exposure prophylaxis, it is not evaluated for COVID-19 PrEP yet. The aim of this study was to evaluate the efficacy and safety of PrEP with hydroxychloroquine against placebo in healthcare workers at high risk of SARS-CoV-2 infection during an epidemic period. METHODS: We conducted a double-blind placebo-controlled randomized clinical trial in three hospitals in Barcelona, Spain. From 350 adult healthcare workers screened, we included 269 participants with no active or past SARS-CoV-2 infection (determined by a negative nasopharyngeal SARS-CoV-2 PCR and a negative serology against SARS-CoV-2). Participants allocated in the intervention arm (PrEP) received 400 mg of hydroxychloroquine daily for the first four consecutive days and subsequently, 400 mg weekly during the study period. Participants in the control group followed the same treatment schedule with placebo tablets. RESULTS: 52.8% (142/269) of participants were in the hydroxychloroquine arm and 47.2% (127/269) in the placebo arm. Given the national epidemic incidence decay, only one participant in each group was diagnosed with COVID-19. The trial was stopped due to futility and our study design was deemed underpowered to evaluate any benefit regarding PrEP efficacy. Both groups showed a similar proportion of participants experiencing at least one adverse event (AE) (p=0.548). No serious AEs were reported. Almost all AEs (96.4%, 106/110) were mild. Only mild gastrointestinal symptoms were significantly higher in the hydroxychloroquine arm compared to the placebo arm (27.4% (39/142) vs 15.7% (20/127), p=0.041). CONCLUSIONS: Although the efficacy of PrEP with hydroxychloroquine for preventing COVID-19 could not be evaluated, our study showed that PrEP with hydroxychloroquine at low doses is safe. TRIAL REGISTRATION: ClinicalTrials.gov NCT04331834 . Registered on April 2, 2020.


Subject(s)
COVID-19 , Pre-Exposure Prophylaxis , Adult , COVID-19/drug therapy , Double-Blind Method , Humans , Hydroxychloroquine/adverse effects , SARS-CoV-2 , Treatment Outcome
14.
Front Immunol ; 12: 750386, 2021.
Article in English | MEDLINE | ID: covidwho-1515534

ABSTRACT

Antibodies targeting Receptor Binding Domain (RBD) of SARS-CoV-2 have been suggested to account for the majority of neutralizing activity in COVID-19 convalescent sera and several neutralizing antibodies (nAbs) have been isolated, characterized and proposed as emergency therapeutics in the form of monoclonal antibodies (mAbs). However, SARS-CoV-2 variants are rapidly spreading worldwide from the sites of initial identification. The variants of concern (VOC) B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma) and B.1.167.2 (Delta) showed mutations in the SARS-CoV-2 spike protein potentially able to cause escape from nAb responses with a consequent reduction of efficacy of vaccines and mAbs-based therapy. We produced the recombinant RBD (rRBD) of SARS-CoV-2 spike glycoprotein from the Wuhan-Hu 1 reference sequence in a mammalian system, for mice immunization to isolate new mAbs with neutralizing activity. Here we describe four mAbs that were able to bind the rRBD in Enzyme-Linked Immunosorbent Assay and the transmembrane full-length spike protein expressed in HEK293T cells by flow cytometry assay. Moreover, the mAbs recognized the RBD in supernatants of SARS-CoV-2 infected VERO E6 cells by Western Blot under non-reducing condition or in supernatants of cells infected with lentivirus pseudotyped for spike protein, by immunoprecipitation assay. Three out of four mAbs lost their binding efficiency to completely N-deglycosylated rRBD and none was able to bind the same recombinant protein expressed in Escherichia coli, suggesting that the epitopes recognized by three mAbs are generated by the conformational structure of the glycosylated native protein. Of particular relevance, three mAbs were able to inhibit Wuhan SARS-CoV-2 infection of VERO E6 cells in a plaque-reduction neutralization test and the Wuhan SARS-CoV-2 as well as the Alpha, Beta, Gamma and Delta VOC in a pseudoviruses-based neutralization test. These mAbs represent important additional tools for diagnosis and therapy of COVID-19 and may contribute to the understanding of the functional structure of SARS-CoV-2 RBD.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/pharmacology , Antibodies, Viral/pharmacology , Epitopes/immunology , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/genetics , Animals , Binding Sites, Antibody/immunology , COVID-19/drug therapy , Cell Line, Tumor , Chlorocebus aethiops , Female , Glycosylation , HEK293 Cells , Humans , Mice, Inbred BALB C , Neutralization Tests , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Vero Cells
15.
Biosci Rep ; 41(10)2021 10 29.
Article in English | MEDLINE | ID: covidwho-1510636

ABSTRACT

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has become a global health emergency. Although new vaccines have been generated and being implicated, discovery and application of novel preventive and control measures are warranted. We aimed to identify compounds that may possess the potential to either block the entry of virus to host cells or attenuate its replication upon infection. Using host cell surface receptor expression (angiotensin-converting enzyme 2 (ACE2) and Transmembrane protease serine 2 (TMPRSS2)) analysis as an assay, we earlier screened several synthetic and natural compounds and identified candidates that showed ability to down-regulate their expression. Here, we report experimental and computational analyses of two small molecules, Mortaparib and MortaparibPlus that were initially identified as dual novel inhibitors of mortalin and PARP-1, for their activity against SARS-CoV-2. In silico analyses showed that MortaparibPlus, but not Mortaparib, stably binds into the catalytic pocket of TMPRSS2. In vitro analysis of control and treated cells revealed that MortaparibPlus caused down-regulation of ACE2 and TMPRSS2; Mortaparib did not show any effect. Furthermore, computational analysis on SARS-CoV-2 main protease (Mpro) that also predicted the inhibitory activity of MortaparibPlus. However, cell-based antiviral drug screening assay showed 30-60% viral inhibition in cells treated with non-toxic doses of either MortaparibPlus or Mortaparib. The data suggest that these two closely related compounds possess multimodal anti-COVID-19 activities. Whereas MortaparibPlus works through direct interactions/effects on the host cell surface receptors (ACE2 and TMPRSS2) and the virus protein (Mpro), Mortaparib involves independent mechanisms, elucidation of which warrants further studies.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/drug therapy , Computational Biology/methods , Angiotensin-Converting Enzyme 2/immunology , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/immunology , COVID-19/immunology , Cell Line, Tumor , Drug Evaluation, Preclinical/methods , HSP70 Heat-Shock Proteins/antagonists & inhibitors , Humans , Mitochondrial Proteins/antagonists & inhibitors , Poly (ADP-Ribose) Polymerase-1/antagonists & inhibitors , SARS-CoV-2/immunology , Serine Endopeptidases/immunology , Serine Endopeptidases/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects
16.
Molecules ; 26(21)2021 Nov 08.
Article in English | MEDLINE | ID: covidwho-1512511

ABSTRACT

This work describes an untargeted analytical approach for the screening, identification, and characterization of the trans-epithelial transport of green tea (Camellia sinensis) catechin extracts with in vitro inhibitory effect against the SARS-CoV-2 papain-like protease (PLpro) activity. After specific catechin extraction, a chromatographic separation obtained six fractions were carried out. The fractions were assessed in vitro against the PLpro target. Fraction 5 showed the highest inhibitory activity against the SARS-CoV-2 PLpro (IC50 of 0.125 µg mL-1). The untargeted characterization revealed that (-)-epicatechin-3-gallate (ECG) was the most abundant compound in the fraction and the primary molecule absorbed by differentiated Caco-2 cells. Results indicated that fraction 5 was approximately 10 times more active than ECG (IC50 value equal to 11.62 ± 0.47 µg mL-1) to inhibit the PLpro target. Overall, our findings highlight the synergistic effects of the various components of the crude extract compared to isolated ECG.


Subject(s)
Catechin/pharmacology , Coronavirus Papain-Like Proteases/metabolism , Tea/metabolism , Antiviral Agents/chemistry , COVID-19/drug therapy , COVID-19/metabolism , Caco-2 Cells , Camellia sinensis/metabolism , Catechin/analogs & derivatives , Catechin/chemistry , Catechin/metabolism , Coronavirus Papain-Like Proteases/drug effects , Epithelium/drug effects , Epithelium/metabolism , Humans , Mass Spectrometry/methods , Plant Extracts/chemistry , Plant Extracts/pharmacology , SARS-CoV-2/drug effects , SARS-CoV-2/metabolism , SARS-CoV-2/pathogenicity , Tea/chemistry , Tea/physiology
17.
Int J Mol Sci ; 22(21)2021 Nov 08.
Article in English | MEDLINE | ID: covidwho-1512382

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic with a great impact on social and economic activities, as well as public health. In most patients, the symptoms of COVID-19 are a high-grade fever and a dry cough, and spontaneously resolve within ten days. However, in severe cases, COVID-19 leads to atypical bilateral interstitial pneumonia, acute respiratory distress syndrome, and systemic thromboembolism, resulting in multiple organ failure with high mortality and morbidity. SARS-CoV-2 has immune evasion mechanisms, including inhibition of interferon signaling and suppression of T cell and B cell responses. SARS-CoV-2 infection directly and indirectly causes dysregulated immune responses, platelet hyperactivation, and endothelial dysfunction, which interact with each other and are exacerbated by cardiovascular risk factors. In this review, we summarize current knowledge on the pathogenic basis of thromboinflammation and endothelial injury in COVID-19. We highlight the distinct contributions of dysregulated immune responses, platelet hyperactivation, and endothelial dysfunction to the pathogenesis of COVID-19. In addition, we discuss potential therapeutic strategies targeting these mechanisms.


Subject(s)
COVID-19/pathology , Endothelium, Vascular/physiopathology , Thrombosis/etiology , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Blood Coagulation , COVID-19/complications , COVID-19/drug therapy , COVID-19/virology , Endothelium, Vascular/metabolism , Humans , Immunity, Innate , Platelet Activation , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology
18.
Drug Des Devel Ther ; 15: 4503-4525, 2021.
Article in English | MEDLINE | ID: covidwho-1511886

ABSTRACT

Curcumin is a natural compound with great potential for disease treatment. A large number of studies have proved that curcumin has a variety of biological activities, among which anti-inflammatory effect is a significant feature of it. Inflammation is a complex and pervasive physiological and pathological process. The physiological and pathological mechanisms of inflammatory bowel disease, psoriasis, atherosclerosis, COVID-19 and other research focus diseases are not clear yet, and they are considered to be related to inflammation. The anti-inflammatory effect of curcumin can effectively improve the symptoms of these diseases and is expected to be a candidate drug for the treatment of related diseases. This paper mainly reviews the anti-inflammatory effect of curcumin, the inflammatory pathological mechanism of related diseases, the regulatory effect of curcumin on these, and the latest research results on the improvement of curcumin pharmacokinetics. It is beneficial to the further study of curcumin and provides new ideas and insights for the development of curcumin anti-inflammatory preparations.


Subject(s)
Anti-Inflammatory Agents/pharmacology , COVID-19/drug therapy , Curcumin/pharmacology , Inflammation/drug therapy , SARS-CoV-2 , Animals , Atherosclerosis/drug therapy , Curcumin/therapeutic use , Depression/drug therapy , Humans
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