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1.
Biomed Res Int ; 2022: 1558860, 2022.
Article in English | MEDLINE | ID: covidwho-1622112

ABSTRACT

Increasing outbreaks of new pathogenic viruses have promoted the exploration of novel alternatives to time-consuming vaccines. Thus, it is necessary to develop a universal approach to halt the spread of new and unknown viruses as they are discovered. One such promising approach is to target lipid membranes, which are common to all viruses and bacteria. The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has reaffirmed the importance of interactions between the virus envelope and the host cell plasma membrane as a critical mechanism of infection. Metadichol®, a nanolipid emulsion of long-chain alcohols, has been demonstrated as a strong candidate that inhibits the proliferation of SARS-CoV-2. Naturally derived substances, such as long-chain saturated lipid alcohols, reduce viral infectivity, including that of coronaviruses (such as SARS-CoV-2) by modifying their lipid-dependent attachment mechanism to human host cells. The receptor ACE2 mediates the entry of SARS-CoV-2 into the host cells, whereas the serine protease TMPRSS2 primes the viral S protein. In this study, Metadichol® was found to be 270 times more potent an inhibitor of TMPRSS2 (EC50 = 96 ng/mL) than camostat mesylate (EC50 = 26000 ng/mL). Additionally, it inhibits ACE with an EC50 of 71 ng/mL, but it is a very weak inhibitor of ACE2 at an EC50 of 31 µg/mL. Furthermore, the live viral assay performed in Caco-2 cells revealed that Metadichol® inhibits SARS-CoV-2 replication at an EC90 of 0.16 µg/mL. Moreover, Metadichol® had an EC90 of 0.00037 µM, making it 2081 and 3371 times more potent than remdesivir (EC50 = 0.77 µM) and chloroquine (EC50 = 1.14 µM), respectively.


Subject(s)
Fatty Alcohols/pharmacology , SARS-CoV-2/drug effects , Viruses/drug effects , Animals , Antiviral Agents/pharmacology , COVID-19/drug therapy , Cell Line , Chlorocebus aethiops , Esters/pharmacology , Guanidines/pharmacology , Humans , Lipid Metabolism/physiology , Lipids/chemistry , SARS-CoV-2/metabolism , SARS-CoV-2/pathogenicity , Serine Endopeptidases/drug effects , Serine Endopeptidases/metabolism , Serine Proteases/metabolism , Serine Proteinase Inhibitors/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells , Virus Attachment/drug effects , Virus Internalization/drug effects
2.
J Allergy Clin Immunol ; 149(3): 923-933.e6, 2022 03.
Article in English | MEDLINE | ID: covidwho-1560006

ABSTRACT

BACKGROUND: Treatments for coronavirus disease 2019, which is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), are urgently needed but remain limited. SARS-CoV-2 infects cells through interactions of its spike (S) protein with angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) on host cells. Multiple cells and organs are targeted, particularly airway epithelial cells. OM-85, a standardized lysate of human airway bacteria with strong immunomodulating properties and an impeccable safety profile, is widely used to prevent recurrent respiratory infections. We found that airway OM-85 administration inhibits Ace2 and Tmprss2 transcription in the mouse lung, suggesting that OM-85 might hinder SARS-CoV-2/host cell interactions. OBJECTIVES: We sought to investigate whether and how OM-85 treatment protects nonhuman primate and human epithelial cells against SARS-CoV-2. METHODS: ACE2 and TMPRSS2 mRNA and protein expression, cell binding of SARS-CoV-2 S1 protein, cell entry of SARS-CoV-2 S protein-pseudotyped lentiviral particles, and SARS-CoV-2 cell infection were measured in kidney, lung, and intestinal epithelial cell lines, primary human bronchial epithelial cells, and ACE2-transfected HEK293T cells treated with OM-85 in vitro. RESULTS: OM-85 significantly downregulated ACE2 and TMPRSS2 transcription and surface ACE2 protein expression in epithelial cell lines and primary bronchial epithelial cells. OM-85 also strongly inhibited SARS-CoV-2 S1 protein binding to, SARS-CoV-2 S protein-pseudotyped lentivirus entry into, and SARS-CoV-2 infection of epithelial cells. These effects of OM-85 appeared to depend on SARS-CoV-2 receptor downregulation. CONCLUSIONS: OM-85 inhibits SARS-CoV-2 epithelial cell infection in vitro by downregulating SARS-CoV-2 receptor expression. Further studies are warranted to assess whether OM-85 may prevent and/or reduce the severity of coronavirus disease 2019.


Subject(s)
Adjuvants, Immunologic/administration & dosage , COVID-19/prevention & control , Cell Extracts/administration & dosage , Receptors, Virus/antagonists & inhibitors , Receptors, Virus/immunology , SARS-CoV-2/immunology , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/immunology , Animals , COVID-19/immunology , COVID-19/virology , Caco-2 Cells , Cell Extracts/immunology , Cells, Cultured , Chlorocebus aethiops , Down-Regulation/drug effects , Epithelial Cells/drug effects , Epithelial Cells/immunology , Epithelial Cells/virology , HEK293 Cells , Host Microbial Interactions/drug effects , Host Microbial Interactions/immunology , Humans , In Vitro Techniques , Lung/drug effects , Lung/immunology , Lung/virology , Mice , Mice, Inbred BALB C , Serine Endopeptidases/drug effects , Serine Endopeptidases/genetics , Serine Endopeptidases/immunology , Transcription, Genetic/drug effects , Transcription, Genetic/immunology , Vero Cells
3.
Proc Natl Acad Sci U S A ; 118(43)2021 10 26.
Article in English | MEDLINE | ID: covidwho-1493345

ABSTRACT

The host cell serine protease TMPRSS2 is an attractive therapeutic target for COVID-19 drug discovery. This protease activates the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and of other coronaviruses and is essential for viral spread in the lung. Utilizing rational structure-based drug design (SBDD) coupled to substrate specificity screening of TMPRSS2, we have discovered covalent small-molecule ketobenzothiazole (kbt) TMPRSS2 inhibitors which are structurally distinct from and have significantly improved activity over the existing known inhibitors Camostat and Nafamostat. Lead compound MM3122 (4) has an IC50 (half-maximal inhibitory concentration) of 340 pM against recombinant full-length TMPRSS2 protein, an EC50 (half-maximal effective concentration) of 430 pM in blocking host cell entry into Calu-3 human lung epithelial cells of a newly developed VSV-SARS-CoV-2 chimeric virus, and an EC50 of 74 nM in inhibiting cytopathic effects induced by SARS-CoV-2 virus in Calu-3 cells. Further, MM3122 blocks Middle East respiratory syndrome coronavirus (MERS-CoV) cell entry with an EC50 of 870 pM. MM3122 has excellent metabolic stability, safety, and pharmacokinetics in mice, with a half-life of 8.6 h in plasma and 7.5 h in lung tissue, making it suitable for in vivo efficacy evaluation and a promising drug candidate for COVID-19 treatment.


Subject(s)
Benzothiazoles/pharmacology , COVID-19/drug therapy , Oligopeptides/pharmacology , SARS-CoV-2/drug effects , Serine Endopeptidases/genetics , Animals , Benzamidines/chemistry , Benzothiazoles/pharmacokinetics , COVID-19/genetics , COVID-19/virology , Cell Line , Drug Design , Epithelial Cells/drug effects , Epithelial Cells/virology , Esters/chemistry , Guanidines/chemistry , Humans , Lung/drug effects , Lung/virology , Mice , Middle East Respiratory Syndrome Coronavirus/drug effects , Middle East Respiratory Syndrome Coronavirus/pathogenicity , Oligopeptides/pharmacokinetics , SARS-CoV-2/pathogenicity , Serine Endopeptidases/drug effects , Serine Endopeptidases/ultrastructure , Small Molecule Libraries/pharmacology , Substrate Specificity/drug effects , Virus Internalization/drug effects
5.
Nutrients ; 13(8)2021 Aug 16.
Article in English | MEDLINE | ID: covidwho-1360797

ABSTRACT

Hesperidin (HD) is a common flavanone glycoside isolated from citrus fruits and possesses great potential for cardiovascular protection. Hesperetin (HT) is an aglycone metabolite of HD with high bioavailability. Through the docking simulation, HD and HT have shown their potential to bind to two cellular proteins: transmembrane serine protease 2 (TMPRSS2) and angiotensin-converting enzyme 2 (ACE2), which are required for the cellular entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our results further found that HT and HD suppressed the infection of VeroE6 cells using lentiviral-based pseudo-particles with wild types and variants of SARS-CoV-2 with spike (S) proteins, by blocking the interaction between the S protein and cellular receptor ACE2 and reducing ACE2 and TMPRSS2 expression. In summary, hesperidin is a potential TMPRSS2 inhibitor for the reduction of the SARS-CoV-2 infection.


Subject(s)
COVID-19/drug therapy , Hesperidin/chemistry , Hesperidin/pharmacology , SARS-CoV-2/drug effects , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/metabolism , COVID-19/virology , Cell Line, Tumor , Chlorocebus aethiops , Coronavirus Papain-Like Proteases/chemistry , Coronavirus Papain-Like Proteases/metabolism , Humans , Molecular Docking Simulation , SARS-CoV-2/metabolism , Serine Endopeptidases/chemistry , Serine Endopeptidases/drug effects , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells
6.
Microbiol Spectr ; 9(1): e0047221, 2021 09 03.
Article in English | MEDLINE | ID: covidwho-1352541

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a causative agent of the coronavirus disease 2019 (COVID-19) pandemic, and the development of therapeutic interventions is urgently needed. So far, monoclonal antibodies and drug repositioning are the main methods for drug development, and this effort was partially successful. Since the beginning of the COVID-19 pandemic, the emergence of SARS-CoV-2 variants has been reported in many parts of the world, and the main concern is whether the current vaccines and therapeutics are still effective against these variant viruses. Viral entry and viral RNA-dependent RNA polymerase (RdRp) are the main targets of current drug development; therefore, the inhibitory effects of transmembrane serine protease 2 (TMPRSS2) and RdRp inhibitors were compared among the early SARS-CoV-2 isolate (lineage A) and the two recent variants (lineage B.1.1.7 and lineage B.1.351) identified in the United Kingdom and South Africa, respectively. Our in vitro analysis of viral replication showed that the drugs targeting TMPRSS2 and RdRp are equally effective against the two variants of concern. IMPORTANCE The COVID-19 pandemic is causing unprecedented global problems in both public health and human society. While some vaccines and monoclonal antibodies were successfully developed very quickly and are currently being used, numerous variants of the causative SARS-CoV-2 are emerging and threatening the efficacy of vaccines and monoclonal antibodies. In order to respond to this challenge, we assessed antiviral efficacy of small-molecule inhibitors that are being developed for treatment of COVID-19 and found that they are still very effective against the SARS-CoV-2 variants. Since most small-molecule inhibitors target viral or host factors other than the mutated sequence of the viral spike protein, they are expected to be potent control measures against the COVID-19 pandemic.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/drug therapy , RNA-Dependent RNA Polymerase/drug effects , SARS-CoV-2/drug effects , Serine Endopeptidases/drug effects , Animals , Antiviral Agents/therapeutic use , Chlorocebus aethiops , Humans , South Africa , United Kingdom , Vero Cells , Virus Internalization/drug effects , Virus Replication/drug effects
7.
Virol J ; 18(1): 154, 2021 07 23.
Article in English | MEDLINE | ID: covidwho-1322940

ABSTRACT

The COVID-19 pandemic has put healthcare infrastructures and our social and economic lives under unprecedented strain. Effective solutions are needed to end the pandemic while significantly lessening its further impact on mortality and social and economic life. Effective and widely-available vaccines have appropriately long been seen as the best way to end the pandemic. Indeed, the current availability of several effective vaccines are already making a significant progress towards achieving that goal. Nevertheless, concerns have risen due to new SARS-CoV-2 variants that harbor mutations against which current vaccines are less effective. Furthermore, some individuals are unwilling or unable to take the vaccine. As health officials across the globe scramble to vaccinate their populations to reach herd immunity, the challenges noted above indicate that COVID-19 therapeutics are still needed to work alongside the vaccines. Here we describe the impact that neutralizing antibodies have had on those with early or mild COVID-19, and what their approval for early management of COVID-19 means for other viral entry inhibitors that have a similar mechanism of action. Importantly, we also highlight studies that show that therapeutic strategies involving various viral entry inhibitors such as multivalent antibodies, recombinant ACE2 and miniproteins can be effective not only for pre-exposure prophylaxis, but also in protecting against SARS-CoV-2 antigenic drift and future zoonotic sarbecoviruses.


Subject(s)
COVID-19/drug therapy , COVID-19/virology , SARS-CoV-2/drug effects , Virus Internalization/drug effects , Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/epidemiology , COVID-19 Vaccines/pharmacology , Cathepsins/metabolism , Humans , Mutation , Pandemics , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Serine Endopeptidases/drug effects , Serine Endopeptidases/metabolism , Spike Glycoprotein, Coronavirus/metabolism
8.
Pharmacol Res ; 157: 104859, 2020 07.
Article in English | MEDLINE | ID: covidwho-1318929

ABSTRACT

Outbreak and pandemic of coronavirus SARS-CoV-2 in 2019/2020 will challenge global health for the future. Because a vaccine against the virus will not be available in the near future, we herein try to offer a pharmacological strategy to combat the virus. There exists a number of candidate drugs that may inhibit infection with and replication of SARS-CoV-2. Such drugs comprise inhibitors of TMPRSS2 serine protease and inhibitors of angiotensin-converting enzyme 2 (ACE2). Blockade of ACE2, the host cell receptor for the S protein of SARS-CoV-2 and inhibition of TMPRSS2, which is required for S protein priming may prevent cell entry of SARS-CoV-2. Further, chloroquine and hydroxychloroquine, and off-label antiviral drugs, such as the nucleotide analogue remdesivir, HIV protease inhibitors lopinavir and ritonavir, broad-spectrum antiviral drugs arbidol and favipiravir as well as antiviral phytochemicals available to date may limit spread of SARS-CoV-2 and morbidity and mortality of COVID-19 pandemic.


Subject(s)
Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Peptidyl-Dipeptidase A/drug effects , Pneumonia, Viral/drug therapy , Serine Endopeptidases/drug effects , Angiotensin-Converting Enzyme 2 , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , COVID-19 , Coronavirus Infections/epidemiology , Coronavirus Infections/mortality , Humans , Pandemics , Pneumonia, Viral/epidemiology , Pneumonia, Viral/mortality , SARS-CoV-2 , Serine Proteinase Inhibitors/pharmacology
9.
J Med Virol ; 93(7): 4205-4218, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1263093

ABSTRACT

Epidemiological data shows a discrepancy in COVID-19 susceptibility and outcomes with some regions being more heavily affected than others. However, the factors that determine host susceptibility and pathogenicity remain elusive. An increasing number of publications highlight the role of Transmembrane Serine Protease 2 (TMPRSS2) in the susceptibility of the host cell to SARS-CoV-2. Cleavage of viral spike protein via the host cell's TMPRSS2 enzyme activity mediates viral entry into the host cell. The enzyme synthesis is regulated by the TMPRSS2 gene, which has also been implicated in the entry mechanisms of previously reported Coronavirus infections. In this review, we have investigated the pathogenicity of SARS-CoV-2 and disease susceptibility dependence on the TMPRSS2 gene as expressed in various population groups. We further discuss how the differential expression of this gene in various ethnic groups can affect the SARS-CoV-2 infection and Coronavirus disease (COVID)-19 outcomes. Moreover, promising new TMPRSS2 protease blockers and inhibitors are discussed for COVID-19 treatment.


Subject(s)
COVID-19/drug therapy , Serine Endopeptidases/drug effects , Serine Endopeptidases/metabolism , Anosmia/pathology , COVID-19/pathology , Female , Genetic Predisposition to Disease/genetics , Humans , Male , SARS-CoV-2/drug effects , Serine Endopeptidases/genetics , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects
10.
Endocrinology ; 162(8)2021 08 01.
Article in English | MEDLINE | ID: covidwho-1259229

ABSTRACT

Coronavirus disease 2019 (COVID-19) is characterized by a gender disparity in severity, with men exhibiting higher hospitalization and mortality rates than women. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, infects cells following recognition and attachment of the viral spike glycoprotein to the angiotensin-converting enzyme 2 transmembrane protein, followed by spike protein cleavage and activation by cell surface transmembrane protease serine 2 (TMPRSS2). In prostate cancer cells, androgen acting on the androgen receptor increases TMPRSS2 expression, which has led to the hypothesis that androgen-dependent expression of TMPRSS2 in the lung may increase men's susceptibility to severe COVID-19 and that, accordingly, suppressing androgen production or action may mitigate COVID-19 severity by reducing SARS-CoV-2 amplification. Several ongoing clinical trials are testing the ability of androgen deprivation therapies or anti-androgens to mitigate COVID-19. This perspective discusses clinical and molecular advances on the rapidly evolving field of androgen receptor (AR) action on cell surface transmembrane protease serine 2 (TMPRSS2) expression and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and the potential effect of anti-androgens on coronavirus disease 2019 (COVID-19) severity in male patients. It discusses limitations of current studies and offers insight for future directions.


Subject(s)
Androgen Antagonists/therapeutic use , COVID-19/drug therapy , SARS-CoV-2 , Animals , Gene Expression/drug effects , Humans , Lung/metabolism , Lung/virology , Male , Mice , Prostatic Neoplasms/drug therapy , Receptors, Androgen/drug effects , Receptors, Androgen/physiology , SARS-CoV-2/physiology , Serine Endopeptidases/drug effects , Serine Endopeptidases/genetics , Serine Endopeptidases/physiology , Sex Factors
11.
Viruses ; 13(5)2021 05 02.
Article in English | MEDLINE | ID: covidwho-1224250

ABSTRACT

In late 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic emerged to severely impact the global population, creating an unprecedented need for effective treatments. This study aims to investigate the potential of Scutellaria barbata D. Don (SB) as a treatment for SARS-CoV-2 infection through the inhibition of the proteases playing important functions in the infection by SARS-CoV-2. FRET assay was applied to investigate the inhibitory effects of SB on the two proteases involved in SARS-CoV-2 infection, Mpro and TMPRSS2. Additionally, to measure the potential effectiveness of SB treatment on infection inhibition, cellular models based on the Calu3 and VeroE6 cells and their TMPRSS2- expressing derivatives were assessed by viral pseudoparticles (Vpp) infection assays. The experimental approaches were conjugated with LC/MS analyses of the aqueous extracts of SB to identify the major constituent compounds, followed by a literature review to determine the potential active components of the inhibitory effects on protease activities. Our results showed that SB extracts inhibited the enzyme activities of Mpro and TMPRSS2. Furthermore, SB extracts effectively inhibited SARS-CoV-2 Vpp infection through a TMPRSS2-dependent mechanism. The aqueous extract analysis identified six major constituent compounds present in SB. Some of them have been known associated with inhibitory activities of TMPRSS2 or Mpro. Thus, SB may effectively prevent SARS-CoV-2 infection and replication through inhibiting Mpro and TMPRSS2 protease activities.


Subject(s)
COVID-19/drug therapy , Coronavirus 3C Proteases/metabolism , Plant Extracts/pharmacology , Serine Endopeptidases/metabolism , Animals , COVID-19/metabolism , Cell Line , Chlorocebus aethiops , Coronavirus 3C Proteases/drug effects , Humans , Lung/virology , Pandemics , Peptide Hydrolases , Peptidyl-Dipeptidase A/metabolism , Plant Extracts/metabolism , Proteolysis , SARS-CoV-2/drug effects , SARS-CoV-2/pathogenicity , Scutellaria , Serine Endopeptidases/drug effects , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects
12.
Sci Rep ; 11(1): 5207, 2021 03 04.
Article in English | MEDLINE | ID: covidwho-1118818

ABSTRACT

The strain SARS-CoV-2, newly emerged in late 2019, has been identified as the cause of COVID-19 and the pandemic declared by WHO in early 2020. Although lipids have been shown to possess antiviral efficacy, little is currently known about lipid compounds with anti-SARS-CoV-2 binding and entry properties. To address this issue, we screened, overall, 17 polyunsaturated fatty acids, monounsaturated fatty acids and saturated fatty acids, as wells as lipid-soluble vitamins. In performing target-based ligand screening utilizing the RBD-SARS-CoV-2 sequence, we observed that polyunsaturated fatty acids most effectively interfere with binding to hACE2, the receptor for SARS-CoV-2. Using a spike protein pseudo-virus, we also found that linolenic acid and eicosapentaenoic acid significantly block the entry of SARS-CoV-2. In addition, eicosapentaenoic acid showed higher efficacy than linolenic acid in reducing activity of TMPRSS2 and cathepsin L proteases, but neither of the fatty acids affected their expression at the protein level. Also, neither reduction of hACE2 activity nor binding to the hACE2 receptor upon treatment with these two fatty acids was observed. Although further in vivo experiments are warranted to validate the current findings, our study provides a new insight into the role of lipids as antiviral compounds against the SARS-CoV-2 strain.


Subject(s)
COVID-19/prevention & control , Fatty Acids, Omega-3/therapeutic use , SARS-CoV-2/drug effects , Virus Attachment/drug effects , Virus Internalization/drug effects , A549 Cells , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/metabolism , Cathepsin L/antagonists & inhibitors , Fatty Acids, Omega-3/pharmacology , Humans , Serine Endopeptidases/drug effects
13.
PLoS Pathog ; 17(1): e1009212, 2021 01.
Article in English | MEDLINE | ID: covidwho-1034957

ABSTRACT

Hydroxychloroquine, used to treat malaria and some autoimmune disorders, potently inhibits viral infection of SARS coronavirus (SARS-CoV-1) and SARS-CoV-2 in cell-culture studies. However, human clinical trials of hydroxychloroquine failed to establish its usefulness as treatment for COVID-19. This compound is known to interfere with endosomal acidification necessary to the proteolytic activity of cathepsins. Following receptor binding and endocytosis, cathepsin L can cleave the SARS-CoV-1 and SARS-CoV-2 spike (S) proteins, thereby activating membrane fusion for cell entry. The plasma membrane-associated protease TMPRSS2 can similarly cleave these S proteins and activate viral entry at the cell surface. Here we show that the SARS-CoV-2 entry process is more dependent than that of SARS-CoV-1 on TMPRSS2 expression. This difference can be reversed when the furin-cleavage site of the SARS-CoV-2 S protein is ablated or when it is introduced into the SARS-CoV-1 S protein. We also show that hydroxychloroquine efficiently blocks viral entry mediated by cathepsin L, but not by TMPRSS2, and that a combination of hydroxychloroquine and a clinically-tested TMPRSS2 inhibitor prevents SARS-CoV-2 infection more potently than either drug alone. These studies identify functional differences between SARS-CoV-1 and -2 entry processes, and provide a mechanistic explanation for the limited in vivo utility of hydroxychloroquine as a treatment for COVID-19.


Subject(s)
COVID-19/prevention & control , Hydroxychloroquine/pharmacology , SARS-CoV-2/drug effects , Serine Endopeptidases/drug effects , Spike Glycoprotein, Coronavirus/drug effects , Virus Internalization/drug effects , Animals , COVID-19/drug therapy , Chlorocebus aethiops/virology , Humans , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells/virology
14.
Diabetes ; 70(3): 759-771, 2021 03.
Article in English | MEDLINE | ID: covidwho-976150

ABSTRACT

The causes of the increased risk of severe coronavirus disease 2019 (COVID-19) in people with diabetes are unclear. It has been speculated that renin-angiotensin system (RAS) blockers may promote COVID-19 by increasing ACE2, which severe acute respiratory syndrome coronavirus 2 uses to enter host cells, along with the host protease TMPRSS2. Taking a reverse translational approach and by combining in situ hybridization, primary cell isolation, immunoblotting, quantitative RT-PCR, and liquid chromatography-tandem mass spectrometry, we studied lung and kidney ACE2 and TMPRSS2 in diabetic mice mimicking host factors linked to severe COVID-19. In healthy young mice, neither the ACE inhibitor ramipril nor the AT1 receptor blocker telmisartan affected lung or kidney ACE2 or TMPRSS2, except for a small increase in kidney ACE2 protein with ramipril. In contrast, mice with comorbid diabetes (aging, high-fat diet, and streptozotocin-induced diabetes) had heightened lung ACE2 and TMPRSS2 protein levels and increased lung ACE2 activity. None of these parameters were affected by RAS blockade. ACE2 was similarly upregulated in the kidneys of mice with comorbid diabetes compared with aged controls, whereas TMPRSS2 (primarily distal nephron) was highest in telmisartan-treated animals. Upregulation of lung ACE2 activity in comorbid diabetes may contribute to an increased risk of severe COVID-19. This upregulation is driven by comorbidity and not by RAS blockade.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , Diabetes Mellitus, Experimental/metabolism , Diet, High-Fat , Kidney/metabolism , Lung/metabolism , Serine Endopeptidases/genetics , Age Factors , Angiotensin II Type 1 Receptor Blockers/pharmacology , Angiotensin-Converting Enzyme 2/drug effects , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , COVID-19 , Immunoblotting , In Situ Hybridization , Kidney/drug effects , Lung/drug effects , Male , Mice , Ramipril/pharmacology , Receptors, Coronavirus/drug effects , Receptors, Coronavirus/genetics , Receptors, Coronavirus/metabolism , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Serine Endopeptidases/drug effects , Serine Endopeptidases/metabolism , Telmisartan/pharmacology
15.
J Cardiovasc Pharmacol ; 77(3): 323-331, 2020 12 04.
Article in English | MEDLINE | ID: covidwho-960615

ABSTRACT

ABSTRACT: The high mortality of specific groups from COVID-19 highlights the importance of host-viral interactions and the potential benefits from enhancing host defenses. SARS-CoV-2 requires angiotensin-converting enzyme (ACE) 2 as a receptor for cell entry and infection. Although both ACE inhibitors and spironolactone can upregulate tissue ACE2, there are important points of discrimination between these approaches. The virus requires proteolytic processing of its spike protein by transmembrane protease receptor serine type 2 (TMPRSS2) to enable binding to cellular ACE2. Because TMPRSS2 contains an androgen promoter, it may be downregulated by the antiandrogenic actions of spironolactone. Furin and plasmin also process the spike protein. They are inhibited by protease nexin 1 or serpin E2 (PN1) that is upregulated by angiotensin II but downregulated by aldosterone. Therefore, spironolactone should selectively downregulate furin and plasmin. Furin also promotes pulmonary edema, whereas plasmin promotes hemovascular dysfunction. Thus, a downregulation of furin and plasmin by PN1 could be a further benefit of MRAs beyond their well-established organ protection. We review the evidence that spironolactone may be the preferred RASSi to increase PN1 and decrease TMPRSS2, furin, and plasmin activities and thereby reduce viral cell binding, entry, infectivity, and bad outcomes. This hypothesis requires direct investigation.


Subject(s)
COVID-19/drug therapy , Mineralocorticoid Receptor Antagonists/therapeutic use , Renin-Angiotensin System/drug effects , Spironolactone/therapeutic use , Humans , Serine Endopeptidases/drug effects
16.
Med Hypotheses ; 146: 110394, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-919589

ABSTRACT

No definitive treatment for COVID-19 exists although promising results have been reported with remdesivir and glucocorticoids. Short of a truly effective preventive or curative vaccine against SARS-CoV-2, it is becoming increasingly clear that multiple pathophysiologic processes seen with COVID-19 as well as SARS-CoV-2 itself should be targeted. Because alpha-1-antitrypsin (AAT) embraces a panoply of biologic activities that may antagonize several pathophysiologic mechanisms induced by SARS-CoV-2, we hypothesize that this naturally occurring molecule is a promising agent to ameliorate COVID-19. We posit at least seven different mechanisms by which AAT may alleviate COVID-19. First, AAT is a serine protease inhibitor (SERPIN) shown to inhibit TMPRSS-2, the host serine protease that cleaves the spike protein of SARS-CoV-2, a necessary preparatory step for the virus to bind its cell surface receptor ACE2 to gain intracellular entry. Second, AAT has anti-viral activity against other RNA viruses HIV and influenza as well as induces autophagy, a known host effector mechanism against MERS-CoV, a related coronavirus that causes the Middle East Respiratory Syndrome. Third, AAT has potent anti-inflammatory properties, in part through inhibiting both nuclear factor-kappa B (NFκB) activation and ADAM17 (also known as tumor necrosis factor-alpha converting enzyme), and thus may dampen the hyper-inflammatory response of COVID-19. Fourth, AAT inhibits neutrophil elastase, a serine protease that helps recruit potentially injurious neutrophils and implicated in acute lung injury. AAT inhibition of ADAM17 also prevents shedding of ACE2 and hence may preserve ACE2 inhibition of bradykinin, reducing the ability of bradykinin to cause a capillary leak in COVID-19. Fifth, AAT inhibits thrombin, and venous thromboembolism and in situ microthrombi and macrothrombi are increasingly implicated in COVID-19. Sixth, AAT inhibition of elastase can antagonize the formation of neutrophil extracellular traps (NETs), a complex extracellular structure comprised of neutrophil-derived DNA, histones, and proteases, and implicated in the immunothrombosis of COVID-19; indeed, AAT has been shown to change the shape and adherence of non-COVID-19-related NETs. Seventh, AAT inhibition of endothelial cell apoptosis may limit the endothelial injury linked to severe COVID-19-associated acute lung injury, multi-organ dysfunction, and pre-eclampsia-like syndrome seen in gravid women. Furthermore, because both NETs formation and the presence of anti-phospholipid antibodies are increased in both COVID-19 and non-COVID pre-eclampsia, it suggests a similar vascular pathogenesis in both disorders. As a final point, AAT has an excellent safety profile when administered to patients with AAT deficiency and is dosed intravenously once weekly but also comes in an inhaled preparation. Thus, AAT is an appealing drug candidate to treat COVID-19 and should be studied.


Subject(s)
COVID-19/drug therapy , Models, Biological , alpha 1-Antitrypsin/therapeutic use , Acute Lung Injury/drug therapy , Anti-Inflammatory Agents/therapeutic use , Antithrombins/therapeutic use , Antiviral Agents/therapeutic use , Apoptosis/drug effects , COVID-19/physiopathology , Extracellular Traps/drug effects , Host Microbial Interactions/drug effects , Host Microbial Interactions/physiology , Humans , Leukocyte Elastase/antagonists & inhibitors , Pandemics , SARS-CoV-2/drug effects , SARS-CoV-2/pathogenicity , SARS-CoV-2/physiology , Serine Endopeptidases/drug effects , Serine Endopeptidases/physiology , Virus Internalization/drug effects , alpha 1-Antitrypsin/administration & dosage
17.
Basic Clin Pharmacol Toxicol ; 128(2): 204-212, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-919229

ABSTRACT

The coronavirus responsible for COVID-19, SARS-CoV-2, utilizes a viral membrane spike protein for host cell entry. For the virus to engage in host membrane fusion, SARS-CoV-2 utilizes the human transmembrane surface protease, TMPRSS2, to cleave and activate the spike protein. Camostat mesylate, an orally available well-known serine protease inhibitor, is a potent inhibitor of TMPRSS2 and has been hypothesized as a potential antiviral drug against COVID-19. In vitro human cell and animal studies have shown that camostat mesylate inhibits virus-cell membrane fusion and hence viral replication. In mice, camostat mesylate treatment during acute infection with influenza, also dependent on TMPRSS2, leads to a reduced viral load. The decreased viral load may be associated with an improved patient outcome. Because camostat mesylate is administered as an oral drug, it may be used in outpatients as well as inpatients at all disease stages of SARS-CoV-2 infection if it is shown to be an effective antiviral agent. Clinical trials are currently ongoing to test whether this well-known drug could be repurposed and utilized to combat the current pandemic. In the following, we will review current knowledge on camostat mesylate mode of action, potential benefits as an antiviral agent and ongoing clinical trials.


Subject(s)
Antiviral Agents/therapeutic use , COVID-19/drug therapy , Esters/therapeutic use , Guanidines/therapeutic use , Serine Proteinase Inhibitors/therapeutic use , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Drug Repositioning , Esters/administration & dosage , Esters/adverse effects , Guanidines/administration & dosage , Guanidines/adverse effects , Humans , Mice , Patient Safety , Serine Endopeptidases/drug effects , Serine Proteinase Inhibitors/administration & dosage , Serine Proteinase Inhibitors/adverse effects
18.
Virus Res ; 289: 198146, 2020 11.
Article in English | MEDLINE | ID: covidwho-733590

ABSTRACT

The rapid emergence of novel coronavirus, SARS-coronavirus 2 (SARS-CoV-2), originated from Wuhan, China, imposed a global health emergency. Angiotensin-converting enzyme 2 (ACE2) receptor serves as an entry point for this deadly virus while the proteases like furin, transmembrane protease serine 2 (TMPRSS2) and 3 chymotrypsin-like protease (3CLpro) are involved in the further processing and replication of SARS-CoV-2. The interaction of SP with ACE2 and these proteases results in the SARS-CoV-2 invasion and fast epidemic spread. The small molecular inhibitors are reported to limit the interaction of SP with ACE2 and other proteases. Arbidol, a membrane fusion inhibitor approved for influenza virus is currently undergoing clinical trials against COVID-19. In this context, we report some analogues of arbidol designed by scaffold morphing and structure-based designing approaches with a superior therapeutic profile. The representative compounds A_BR4, A_BR9, A_BR18, A_BR22 and A_BR28 restricted the interaction of SARS-CoV-2 SP with ACE2 and host proteases furin and TMPRSS2. For 3CLPro, Compounds A_BR5, A_BR6, A_BR9 and A_BR18 exhibited high binding affinity, docking score and key residue interactions. Overall, A_BR18 and A_BR28 demonstrated multi-targeting potential against all the targets. Among these top-scoring molecules A_BR9, A_BR18, A_BR22 and A_BR28 were predicted to confer favorable ADME properties.


Subject(s)
Antiviral Agents/chemistry , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Indoles/chemistry , Pandemics , Peptidyl-Dipeptidase A/drug effects , Pneumonia, Viral/drug therapy , Receptors, Virus/drug effects , Virus Attachment/drug effects , Algorithms , Angiotensin-Converting Enzyme 2 , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Betacoronavirus/physiology , Biological Availability , COVID-19 , Drug Design , Humans , Indoles/metabolism , Indoles/pharmacology , Molecular Docking Simulation , Molecular Structure , Peptide Hydrolases/physiology , Peptidyl-Dipeptidase A/metabolism , Protein Binding , Protein Domains , Receptors, Virus/metabolism , SARS-CoV-2 , Serine Endopeptidases/drug effects , Serine Endopeptidases/metabolism , Spike Glycoprotein, Coronavirus/drug effects , Spike Glycoprotein, Coronavirus/metabolism , Structure-Activity Relationship , Virus Internalization , Virus Replication
19.
Eur J Pharm Sci ; 153: 105495, 2020 Oct 01.
Article in English | MEDLINE | ID: covidwho-676726

ABSTRACT

In December 2019, a new coronavirus was identified in the Hubei province of central china and named SARS-CoV-2. This new virus induces COVID-19, a severe respiratory disease with high death rate. A putative target to interfere with the virus is the host transmembrane serine protease family member II (TMPRSS2). This enzyme is critical for the entry of coronaviruses into human cells by cleaving and activating the spike protein (S) of SARS-CoV-2. Repositioning approved, investigational and experimental drugs on the serine protease domain of TMPRSS2 could thus be valuable. There is no experimental structure for TMPRSS2 but it is possible to develop quality structural models for the serine protease domain using comparative modeling strategies as such domains are highly structurally conserved. Beside the TMPRSS2 catalytic site, we predicted on our structural models a main exosite that could be important for the binding of protein partners and/or substrates. To block the catalytic site or the exosite of TMPRSS2 we used structure-based virtual screening computations and two different collections of approved, investigational and experimental drugs. We propose a list of 156 molecules that could bind to the catalytic site and 100 compounds that may interact with the exosite. These small molecules should now be tested in vitro to gain novel insights over the roles of TMPRSS2 or as starting point for the development of second generation analogs.


Subject(s)
Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , Serine Endopeptidases/drug effects , Spike Glycoprotein, Coronavirus/drug effects , COVID-19 , Catalysis , Computational Biology , Computer Simulation , Drug Repositioning , Humans , Models, Molecular , Pandemics , Serine Proteases/chemistry , Structure-Activity Relationship
20.
Med Hypotheses ; 143: 110112, 2020 Oct.
Article in English | MEDLINE | ID: covidwho-654445

ABSTRACT

In coronavirus disease-19 (COVID-19), four major factors have been correlated with worse prognosis: aging, hypertension, obesity, and exposure to androgen hormones. Angiotensin-converting enzyme-2 (ACE2) receptor, regulation of the renin-angiotensin-aldosterone system (RAAS), and transmembrane serine protease 2 (TMPRSS2) action are critical for the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) cell entry and infectivity. ACE2 expression and RAAS are abnormal in hypertension and obesity, while TMPRSS2 is overexpressed when exposed to androgens, which may justify why these factors are overrepresented in COVID-19. Among therapeutic targets for SARS-CoV-2, we hypothesized that spironolactone, a long used and safe mineralocorticoid and androgen receptors antagonist, with effective anti-hypertensive, cardioprotective, nephroprotective, and anti-androgenic properties may offer pleiotropic actions in different sites to protect from COVID-19. Current data shows that spironolactone may concurrently mitigate abnormal ACE2 expression, correct the balances membrane-attached and free circulating ACE2 and between angiotensin II and Angiotensin-(1-7) (Ang-(1-7)), suppress androgen-mediated TMPRSS2 activity, and inhibit obesity-related RAAS dysfunctions, with consequent decrease of viral priming. Hence, spironolactone may provide protection from SARS-CoV-2, and has sufficient plausibility to be clinically tested, particularly in the early stages of COVID-19.


Subject(s)
Androgen Antagonists/therapeutic use , Androgens/physiology , Betacoronavirus/physiology , Coronavirus Infections/drug therapy , Mineralocorticoid Receptor Antagonists/therapeutic use , Pandemics , Pneumonia, Viral/drug therapy , Renin-Angiotensin System/drug effects , Spironolactone/therapeutic use , Androgen Antagonists/pharmacology , Angiotensin-Converting Enzyme 2 , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , COVID-19 , Cardiotonic Agents/pharmacology , Cardiotonic Agents/therapeutic use , Coronavirus Infections/complications , Coronavirus Infections/epidemiology , Coronavirus Infections/physiopathology , Enzyme Induction/drug effects , Humans , Hypertension/complications , Hypertension/drug therapy , Hypertension/physiopathology , Kidney/drug effects , Male , Mineralocorticoid Receptor Antagonists/pharmacology , Obesity/complications , Obesity/physiopathology , Peptidyl-Dipeptidase A/biosynthesis , Peptidyl-Dipeptidase A/drug effects , Pneumonia, Viral/complications , Pneumonia, Viral/epidemiology , Pneumonia, Viral/physiopathology , Prognosis , Receptors, Virus/drug effects , Risk Factors , SARS-CoV-2 , Serine Endopeptidases/drug effects , Sex Distribution , Spironolactone/pharmacology , Virus Internalization/drug effects
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