Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 12 de 12
Filter
1.
Int J Mol Sci ; 23(5)2022 Mar 03.
Article in English | MEDLINE | ID: covidwho-1732066

ABSTRACT

The endogenous protease furin is a key protein in many different diseases, such as cancer and infections. For this reason, a wide range of studies has focused on targeting furin from a therapeutic point of view. Our main objective consisted of identifying new compounds that could enlarge the furin inhibitor arsenal; secondarily, we assayed their adjuvant effect in combination with a known furin inhibitor, CMK, which avoids the SARS-CoV-2 S protein cleavage by means of that inhibition. Virtual screening was carried out to identify potential furin inhibitors. The inhibition of physiological and purified recombinant furin by screening selected compounds, Clexane, and these drugs in combination with CMK was assayed in fluorogenic tests by using a specific furin substrate. The effects of the selected inhibitors from virtual screening on cell viability (293T HEK cell line) were assayed by means of flow cytometry. Through virtual screening, Zeaxanthin and Kukoamine A were selected as the main potential furin inhibitors. In fluorogenic assays, these two compounds and Clexane inhibited both physiological and recombinant furin in a dose-dependent way. In addition, these compounds increased physiological furin inhibition by CMK, showing an adjuvant effect. In conclusion, we identified Kukoamine A, Zeaxanthin, and Clexane as new furin inhibitors. In addition, these drugs were able to increase furin inhibition by CMK, so they could also increase its efficiency when avoiding S protein proteolysis, which is essential for SARS-CoV-2 cell infection.


Subject(s)
Amino Acid Chloromethyl Ketones/pharmacology , Enoxaparin/pharmacology , Furin/antagonists & inhibitors , Spermine/analogs & derivatives , Zeaxanthins/pharmacology , Amino Acid Chloromethyl Ketones/chemistry , Amino Acid Chloromethyl Ketones/metabolism , COVID-19/transmission , COVID-19/virology , Catalytic Domain , Cell Line, Tumor , Cell Survival/drug effects , Enoxaparin/chemistry , Enoxaparin/metabolism , Furin/chemistry , Furin/metabolism , HEK293 Cells , Humans , Molecular Docking Simulation , Molecular Structure , Protease Inhibitors/chemistry , Protease Inhibitors/metabolism , Protease Inhibitors/pharmacology , Proteolysis , SARS-CoV-2/metabolism , SARS-CoV-2/physiology , Spermine/chemistry , Spermine/metabolism , Spermine/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization , Virus Replication , Zeaxanthins/chemistry , Zeaxanthins/metabolism
2.
Comput Math Methods Med ; 2022: 9735626, 2022.
Article in English | MEDLINE | ID: covidwho-1677416

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was characterized as a pandemic by the World Health Organization (WHO) in Dec. 2019. SARS-CoV-2 binds to the cell membrane through spike proteins on its surface and infects the cell. Furin, a host-cell enzyme, possesses a binding site for the spike protein. Thus, molecules that block furin could potentially be a therapeutic solution. Defensins are antimicrobial peptides that can hypothetically inhibit furin because of their arginine-rich structure. Theta-defensins, a subclass of defensins, have attracted attention as drug candidates due to their small size, unique structure, and involvement in several defense mechanisms. Theta-defensins could be a potential treatment for COVID-19 through furin inhibition and an anti-inflammatory mechanism. Note that inflammatory events are a significant and deadly condition that could happen at the later stages of COVID-19 infection. Here, the potential of theta-defensins against SARS-CoV-2 infection was investigated through in silico approaches. Based on docking analysis results, theta-defensins can function as furin inhibitors. Additionally, a novel candidate peptide against COVID-19 with optimal properties regarding antigenicity, stability, electrostatic potential, and binding strength was proposed. Further in vitro/in vivo investigations could verify the efficiency of the designed novel peptide.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/metabolism , Defensins/pharmacology , Drug Design , Furin/antagonists & inhibitors , Animals , COVID-19/drug therapy , Catalytic Domain , Cell Membrane/virology , Computer Simulation , Data Mining , Furin/chemistry , Humans , Inflammation , Models, Molecular , Molecular Docking Simulation , Peptides/chemistry , Software , Spike Glycoprotein, Coronavirus , Static Electricity
3.
Int J Biol Sci ; 17(14): 3954-3967, 2021.
Article in English | MEDLINE | ID: covidwho-1449161

ABSTRACT

Furin is a proprotein convertase that activates different kinds of regulatory proteins, including SARS-CoV-2 spike protein which contains an additional furin-specific cleavage site. It is essential in predicting cancer patients' susceptibility to SARS-CoV-2 and the disease outcomes due to varying furin expressions in tumor tissues. In this study, we analyzed furin's expression, methylation, mutation rate, functional enrichment, survival rate and COVID-19 outcomes in normal and cancer tissues using online databases, and our IHC. As a result, furin presented with biased expression profiles in normal tissues, showing 12.25-fold higher than ACE2 in the lungs. The furin expression in tumors were significantly increased in ESCA and TGCT, and decreased in DLBC and THYM, indicating furin may play critical mechanistic functions in COVID-19 viral entry into cells in these cancer patients. Line with furin over/downexpression, furin promoter hypo-/hyper-methylation may be the regulatory cause of disease and lead to pathogenesis of ESCA and THYM. Furthermore, presence of FURIN-201 isoform with functional domains (P_proprotein, Peptidase_S8 and S8_pro-domain) is highest in all cancer types in comparison to other isoforms, demonstrating its use in tumorigenesis and SARS-Cov-2 entry into tumor tissues. Furin mutation frequency was highest in UCES, and its mutation might elevate ACE2 expression in LUAD and UCEC, reduce ACE2 expression in COAD, elevate HSPA5 expression in PAAD, and elevate TMPRSS2 expression in BRCA. These results showed that furin mutations mostly increased expression of ACE2, HSPA5, and TMPRSS2 in certain cancers, indicating furin mutations might facilitate COVID-19 cell entry in cancer patients. In addition, high expression of furin was significantly inversely correlated with long overall survival (OS) in LGG and correlated with long OS in COAD and KIRC, indicating that it could be used as a favorable prognostic marker for cancer patients' survival. GO and KEGG demonstrated that furin was mostly enriched in genes for metabolic and biosynthetic processes, retinal dehydrogenase activity, tRNA methyltransferase activity, and genes involving COVID-19, further supporting its role in COVID-19 and cancer metabolism. Moreover, Cordycepin (CD) inhibited furin expression in a dosage dependent manner. Altogether, furin's high expression might not only implies increased susceptibility to SARS-CoV-2 and higher severity of COVID-19 symptoms in cancer patients, but also it highlights the need for cancer treatment and therapy during the COVID-19 pandemic. CD might have a potential to develop an anti-SARS-CoV-2 drug through inhibiting furin expression.


Subject(s)
Antineoplastic Agents/therapeutic use , COVID-19/virology , Deoxyadenosines/therapeutic use , Furin/metabolism , Neoplasms/metabolism , Antineoplastic Agents/pharmacology , COVID-19/complications , Cell Line, Tumor , Deoxyadenosines/pharmacology , Disease Susceptibility , Furin/antagonists & inhibitors , Furin/genetics , Humans , Neoplasms/complications , Protein Isoforms/metabolism , Serine Endopeptidases/metabolism
4.
J Nat Med ; 75(4): 1080-1085, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1375679

ABSTRACT

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contains a cleavage motif R-X-X-R for furin-like enzymes at the boundary of the S1/S2 subunits. The cleavage of the site by cellular proteases is essential for S protein activation and virus entry. We screened the inhibitory effects of crude drugs on in vitro furin-like enzymatic activities using a fluorogenic substrate with whole-cell lysates. Of the 124 crude drugs listed in the Japanese Pharmacopeia, aqueous ethanolic extract of Cnidii Monnieris Fructus, which is the dried fruit of Cnidium monnieri Cussion, significantly inhibited the furin-like enzymatic activities. We further fractionated the plant extract and isolated the two active compounds with the inhibitory activity, namely, imperatorin and osthole, whose IC50 values were 1.45 mM and 9.45 µM, respectively. Our results indicated that Cnidii Monnieris Fructus might exert inhibitory effects on furin-like enzymatic activities, and that imperatorin and osthole of the crude drug could be potential inhibitors of the motif cleavage.


Subject(s)
Cnidium/chemistry , Drug Evaluation, Preclinical , Enzyme Assays , Furin/antagonists & inhibitors , Furin/metabolism , Plant Extracts/pharmacology , A549 Cells , COVID-19/drug therapy , COVID-19/virology , Humans , Inhibitory Concentration 50 , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism
5.
ACS Chem Biol ; 16(9): 1692-1700, 2021 09 17.
Article in English | MEDLINE | ID: covidwho-1366786

ABSTRACT

The pro-protein convertase furin is a highly specific serine protease involved in the proteolytic maturation of many proteins in the secretory pathway. It also activates surface proteins of many viruses including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Furin inhibitors effectively suppress viral replication and thus are promising antiviral therapeutics with broad application potential. Polybasic substrate-like ligands typically trigger conformational changes shifting furin's active site cleft from the OFF-state to the ON-state. Here, we solved the X-ray structures of furin in complex with four different arginine mimetic compounds with reduced basicity. These guanylhydrazone-based inhibitor complexes showed for the first time an active site-directed binding mode to furin's OFF-state conformation. The compounds undergo unique interactions within the S1 pocket, largely different compared to substrate-like ligands. A second binding site was identified at the S4/S5 pocket of furin. Crystallography-based titration experiments confirmed the S1 site as the primary binding pocket. We also tested the proprotein convertases PC5/6 and PC7 for inhibition by guanylhydrazones and found an up to 7-fold lower potency for PC7. Interestingly, the observed differences in the Ki values correlated with the sequence conservation of the PCs at the allosteric sodium binding site. Therefore, OFF-state-specific targeting of furin can serve as a valuable strategy for structure-based development of PC-selective small-molecule inhibitors.


Subject(s)
Antiviral Agents/metabolism , Furin/antagonists & inhibitors , Guanidines/metabolism , Hydrazones/metabolism , Serine Proteinase Inhibitors/metabolism , Antiviral Agents/chemistry , Catalytic Domain , Crystallography, X-Ray , Enzyme Assays , Furin/chemistry , Furin/metabolism , Guanidines/chemistry , HEK293 Cells , Humans , Hydrazones/chemistry , Kinetics , Proprotein Convertase 5/antagonists & inhibitors , Proprotein Convertase 5/chemistry , Protein Binding , Protein Conformation , Serine Proteinase Inhibitors/chemistry , Subtilisins/antagonists & inhibitors , Subtilisins/chemistry
6.
J Med Chem ; 65(4): 2747-2784, 2022 02 24.
Article in English | MEDLINE | ID: covidwho-1338518

ABSTRACT

Analysis of the SARS-CoV-2 sequence revealed a multibasic furin cleavage site at the S1/S2 boundary of the spike protein distinguishing this virus from SARS-CoV. Furin, the best-characterized member of the mammalian proprotein convertases, is an ubiquitously expressed single pass type 1 transmembrane protein. Cleavage of SARS-CoV-2 spike protein by furin promotes viral entry into lung cells. While furin knockout is embryonically lethal, its knockout in differentiated somatic cells is not, thus furin provides an exciting therapeutic target for viral pathogens including SARS-CoV-2 and bacterial infections. Several peptide-based and small-molecule inhibitors of furin have been recently reported, and select cocrystal structures have been solved, paving the way for further optimization and selection of clinical candidates. This perspective highlights furin structure, substrates, recent inhibitors, and crystal structures with emphasis on furin's role in SARS-CoV-2 infection, where the current data strongly suggest its inhibition as a promising therapeutic intervention for SARS-CoV-2.


Subject(s)
Antiviral Agents/pharmacology , Furin/antagonists & inhibitors , Peptides/pharmacology , SARS-CoV-2/drug effects , Small Molecule Libraries/pharmacology , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Animals , Antiviral Agents/chemistry , COVID-19/drug therapy , COVID-19/metabolism , Furin/metabolism , Humans , Peptides/chemistry , SARS-CoV-2/metabolism , Small Molecule Libraries/chemistry , Spike Glycoprotein, Coronavirus/metabolism
7.
mBio ; 12(4): e0058721, 2021 08 31.
Article in English | MEDLINE | ID: covidwho-1327613

ABSTRACT

Since the D614G substitution in the spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged, the variant strain has undergone a rapid expansion to become the most abundant strain worldwide. Therefore, this substitution may provide an advantage for viral spreading. To explore the mechanism, we analyzed 18 viral isolates containing S proteins with either G614 or D614 (S-G614 and S-D614, respectively). The plaque assay showed a significantly higher virus titer in S-G614 than in S-D614 isolates. We further found increased cleavage of the S protein at the furin substrate site, a key event that promotes syncytium formation, in S-G614 isolates. The enhancement of the D614G substitution in the cleavage of the S protein and in syncytium formation has been validated in cells expressing S protein. The effect on the syncytium was abolished by furin inhibitor treatment and mutation of the furin cleavage site, suggesting its dependence on cleavage by furin. Our study pointed to the impact of the D614G substitution on syncytium formation through enhanced furin-mediated S cleavage, which might increase the transmissibility and infectivity of SARS-CoV-2 strains containing S-G614. IMPORTANCE Analysis of viral genomes and monitoring of the evolutionary trajectory of SARS-CoV-2 over time has identified the D614G substitution in spike (S) as the most prevalent expanding variant worldwide, which might confer a selective advantage in transmission. Several studies showed that the D614G variant replicates and transmits more efficiently than the wild-type virus, but the mechanism is unclear. By comparing 18 virus isolates containing S with either D614 or G614, we found significantly higher virus titers in association with higher furin protease-mediated cleavage of S, an event that promotes syncytium formation and virus infectivity, in the S-G614 viruses. The effect of the D614G substitution on furin-mediated S cleavage and the resulting enhancement of the syncytium phenotype has been validated in S-expressing cells. This study suggests a possible effect of the D614G substitution on S of SARS-CoV-2; the antiviral effect through targeting furin protease is worthy of being investigated in proper animal models.


Subject(s)
COVID-19/transmission , Furin/metabolism , Giant Cells/virology , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Amino Acid Substitution/genetics , Animals , COVID-19/pathology , Cell Line , Chlorocebus aethiops , Furin/antagonists & inhibitors , Genetic Fitness/genetics , Genome, Viral/genetics , HEK293 Cells , Humans , SARS-CoV-2/isolation & purification , Vero Cells , Viral Load/genetics , Virus Replication/genetics
8.
J Proteome Res ; 20(1): 49-59, 2021 01 01.
Article in English | MEDLINE | ID: covidwho-989659

ABSTRACT

Since the novel coronavirus pandemic, people around the world have been touched in varying degrees, and this pandemic has raised a major global health concern. As there is no effective drug or vaccine, it is urgent to find therapeutic drugs that can serve to deal with the current epidemic situation in all countries and regions. We searched drugs and response measures for SARS-CoV-2 in the PubMed database, and then updated the potential targets and therapeutic drugs from the perspective of the viral replication cycle. The drug research studies of the viral replication cycle are predominantly focused on the process of the virus entering cells, proteases, and RdRp. The inhibitors of the virus entry to cells and RdRp, such as Arbidol, remdesivir, favipiravir, EIDD-2081, and ribavirin, are in clinical trials, while most of the protease inhibitors are mainly calculated by molecular docking technology, which needs in vivo and in vitro experiments to prove the effect for SARS-CoV-2. This review summarizes the drugs targeting the viral replication process and provides a basis and directions for future drug development and reuse on the protein level of COVID-19.


Subject(s)
Antiviral Agents/pharmacology , SARS-CoV-2/drug effects , Virus Replication/drug effects , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antiviral Agents/chemistry , Basigin/metabolism , Coronavirus 3C Proteases/antagonists & inhibitors , Coronavirus 3C Proteases/metabolism , Coronavirus Nucleocapsid Proteins/chemistry , Coronavirus Nucleocapsid Proteins/metabolism , Coronavirus RNA-Dependent RNA Polymerase/metabolism , Dipeptidyl Peptidase 4/metabolism , Furin/antagonists & inhibitors , Furin/metabolism , Host-Pathogen Interactions/drug effects , Humans , SARS-CoV-2/pathogenicity , SARS-CoV-2/physiology , Serine Endopeptidases/metabolism , Small Molecule Libraries/pharmacology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
9.
Phytomedicine ; 85: 153396, 2021 May.
Article in English | MEDLINE | ID: covidwho-929314

ABSTRACT

BACKGROUND: Currently, novel coronavirus disease (Covid-19) outbreak creates global panic across the continents, as people from almost all countries and territories have been affected by this highly contagious viral disease. The scenario is deteriorating due to lack of proper & specific target-oriented pharmacologically safe prophylactic agents or drugs, and or any effective vaccine. drug development is urgently required to back in the normalcy in the community and to combat this pandemic. PURPOSE: Thus, we have proposed two novel drug targets, Furin and TMPRSS2, as Covid-19 treatment strategy. We have highlighted this target-oriented novel drug delivery strategy, based on their pathophysiological implication on SARS-CoV-2 infection, as evident from earlier SARS-CoV-1, MERS, and influenza virus infection via host cell entry, priming, fusion, and endocytosis. STUDY DESIGN &  METHODS: An earlier study suggested that Furin and TMPRSS2 knockout mice had reduced level of viral load and a lower degree of organ damage such as the lung. The present study thus highlights the promise of some selected novel and potential anti-viral Phytopharmaceutical that bind to Furin and TMPRSS2 as target. RESULT: Few of them had shown promising anti-viral response in both preclinical and clinical study with acceptable therapeutic safety-index. CONCLUSION: Hence, this strategy may limit life-threatening Covid-19 infection and its mortality rate through nano-suspension based intra-nasal or oral nebulizer spray, to treat mild to moderate SARS-COV-2 infection when Furin and TMPRSS2 receptor may initiate to express and activate for processing the virus to cause cellular infection by replication within the host cell and blocking of host-viral interaction.


Subject(s)
COVID-19/drug therapy , Furin/antagonists & inhibitors , Phytochemicals/pharmacology , Receptors, Virus/antagonists & inhibitors , Serine Endopeptidases/metabolism , Serine Proteinase Inhibitors/pharmacology , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Animals , Furin/metabolism , Humans , Mice , Mice, Knockout , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism
11.
Cell Rep ; 33(2): 108254, 2020 10 13.
Article in English | MEDLINE | ID: covidwho-812312

ABSTRACT

Development of specific antiviral agents is an urgent unmet need for SARS-coronavirus 2 (SARS-CoV-2) infection. This study focuses on host proteases that proteolytically activate the SARS-CoV-2 spike protein, critical for its fusion after binding to angiotensin-converting enzyme 2 (ACE2), as antiviral targets. We first validate cleavage at a putative furin substrate motif at SARS-CoV-2 spikes by expressing it in VeroE6 cells and find prominent syncytium formation. Cleavage and the syncytium are abolished by treatment with the furin inhibitors decanoyl-RVKR-chloromethylketone (CMK) and naphthofluorescein, but not by the transmembrane protease serine 2 (TMPRSS2) inhibitor camostat. CMK and naphthofluorescein show antiviral effects on SARS-CoV-2-infected cells by decreasing virus production and cytopathic effects. Further analysis reveals that, similar to camostat, CMK blocks virus entry, but it further suppresses cleavage of spikes and the syncytium. Naphthofluorescein acts primarily by suppressing viral RNA transcription. Therefore, furin inhibitors may be promising antiviral agents for prevention and treatment of SARS-CoV-2 infection.


Subject(s)
Amino Acid Chloromethyl Ketones/pharmacology , Antiviral Agents/pharmacology , Fluoresceins/pharmacology , Furin/antagonists & inhibitors , Protease Inhibitors/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Virus Replication , Animals , Betacoronavirus/drug effects , Betacoronavirus/metabolism , Betacoronavirus/physiology , Chlorocebus aethiops , Humans , Proteolysis , SARS-CoV-2 , Vero Cells
12.
Phytother Res ; 35(2): 908-919, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-777655

ABSTRACT

COVID-19 pandemic is currently decimating the world's most advanced technologies and largest economies and making its way to the continent of Africa. Weak medical infrastructure and over-reliance on medical aids may eventually predict worse outcomes in Africa. To reverse this trend, Africa must re-evaluate the only area with strategic advantage; phytotherapy. One of the many plants with previous antiviral potency is against RNA viruses is Aframomum melegueta. In this study, one hundred (100) A. melegueta secondary metabolites have been mined and computational evaluated for inhibition of host furin, and SARS-COV-2 targets including 3C-like proteinase (Mpro /3CLpro ), 2'-O-ribose methyltransferase (nsp16) and surface glycoprotein/ACE2 receptor interface. Silica-gel column partitioning of A. melegueta fruit/seed resulted in 6 fractions tested against furin activity. Diarylheptanoid (Letestuianin A), phenylpropanoid (4-Cinnamoyl-3-hydroxy-spiro[furan-5,2'-(1'H)-indene]-1',2,3'(2'H,5H)-trione), flavonoids (Quercetin, Apigenin and Tectochrysin) have been identified as high-binding compounds to SARS-COV-2 targets in a polypharmacology manner. Di-ethyl-ether (IC50 = 0.03 mg/L), acetone (IC50 = 1.564 mg/L), ethyl-acetate (IC50 = 0.382 mg/L) and methanol (IC50 = 0.438 mg/L) fractions demonstrated the best inhibition in kinetic assay while DEF, ASF and MEF completely inhibited furin-recognition sequence containing Ebola virus-pre-glycoprotein. In conclusion, A. melegueta and its secondary metabolites have potential for addressing the therapeutic needs of African population during the COVID-19 pandemic.


Subject(s)
COVID-19/drug therapy , Furin/antagonists & inhibitors , Phytotherapy/methods , Plant Extracts/therapeutic use , SARS-CoV-2/drug effects , Zingiberaceae/chemistry , COVID-19/epidemiology , Drug Evaluation, Preclinical/methods , Fruit/chemistry , Fruit/metabolism , Furin/metabolism , Humans , In Vitro Techniques , Metabolome/physiology , Molecular Docking Simulation , Pandemics , Plant Extracts/chemistry , Plant Extracts/metabolism , Polypharmacology , SARS-CoV-2/pathogenicity , Seeds/chemistry , Seeds/metabolism , Zingiberaceae/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL