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1.
Nat Commun ; 11(1): 4682, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943628

RESUMO

The ongoing Corona Virus Disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has emphasized the urgent need for antiviral therapeutics. The viral RNA-dependent-RNA-polymerase (RdRp) is a promising target with polymerase inhibitors successfully used for the treatment of several viral diseases. We demonstrate here that Favipiravir predominantly exerts an antiviral effect through lethal mutagenesis. The SARS-CoV RdRp complex is at least 10-fold more active than any other viral RdRp known. It possesses both unusually high nucleotide incorporation rates and high-error rates allowing facile insertion of Favipiravir into viral RNA, provoking C-to-U and G-to-A transitions in the already low cytosine content SARS-CoV-2 genome. The coronavirus RdRp complex represents an Achilles heel for SARS-CoV, supporting nucleoside analogues as promising candidates for the treatment of COVID-19.


Assuntos
Amidas/farmacologia , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/genética , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Pirazinas/farmacologia , Amidas/farmacocinética , Animais , Antivirais/farmacocinética , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Modelos Moleculares , Mutagênese/efeitos dos fármacos , Pandemias , Pneumonia Viral/virologia , Pirazinas/farmacocinética , RNA Replicase/química , RNA Replicase/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Análise de Sequência , Células Vero , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
2.
Nat Commun ; 11(1): 4607, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929081

RESUMO

Drug tolerance is the basis for acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) including osimertinib, through mechanisms that still remain unclear. Here, we show that while AXL-low expressing EGFR mutated lung cancer (EGFRmut-LC) cells are more sensitive to osimertinib than AXL-high expressing EGFRmut-LC cells, a small population emerge osimertinib tolerance. The tolerance is mediated by the increased expression and phosphorylation of insulin-like growth factor-1 receptor (IGF-1R), caused by the induction of its transcription factor FOXA1. IGF-1R maintains association with EGFR and adaptor proteins, including Gab1 and IRS1, in the presence of osimertinib and restores the survival signal. In AXL-low-expressing EGFRmut-LC cell-derived xenograft and patient-derived xenograft models, transient IGF-1R inhibition combined with continuous osimertinib treatment could eradicate tumors and prevent regrowth even after the cessation of osimertinib. These results indicate that optimal inhibition of tolerant signals combined with osimertinib may dramatically improve the outcome of EGFRmut-LC.


Assuntos
Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Acrilamidas/farmacologia , Idoso de 80 Anos ou mais , Compostos de Anilina/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Regulação para Cima/efeitos dos fármacos
3.
Sci Rep ; 10(1): 14290, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868801

RESUMO

Several drug candidates have been proposed and tested as the latest clinical treatment for coronavirus pneumonia (COVID-19). Chloroquine, hydroxychloroquine, ritonavir/lopinavir, and favipiravir are under trials for the treatment of this disease. The hyperpolarization technique has the ability to further provide a better understanding of the roles of these drugs at the molecular scale and in different applications in the field of nuclear magnetic resonance/magnetic resonance imaging. This technique may provide new opportunities in diagnosis and research of COVID-19. Signal amplification by reversible exchange-based hyperpolarization studies on large-sized drug candidates were carried out. We observed hyperpolarized proton signals from whole structures, due to the unprecedented long-distance polarization transfer by para-hydrogen. We also found that the optimal magnetic field for the maximum polarization transfer yield was dependent on the molecular structure. We can expect further research on the hyperpolarization of other important large molecules, isotope labeling, as well as polarization transfer on nuclei with a long spin relaxation time. A clinical perspective of these features on drug molecules can broaden the application of hyperpolarization techniques for therapeutic studies.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/virologia , Descoberta de Drogas , Pneumonia Viral/virologia , Amidas/química , Amidas/farmacologia , Antivirais/química , Cloroquina/química , Cloroquina/farmacologia , Infecções por Coronavirus/diagnóstico , Descoberta de Drogas/métodos , Humanos , Lopinavir/química , Lopinavir/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pandemias , Pneumonia Viral/diagnóstico , Pirazinas/química , Pirazinas/farmacologia , Ritonavir/química , Ritonavir/farmacologia
4.
Anticancer Res ; 40(7): 3781-3792, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32620617

RESUMO

BACKGROUND/AIM: Canine B-cell lymphoma represents a useful in vivo model for human diffuse large B-cell lymphoma (DLBCL). Pan-Bromodomain and extra-terminal (BET) inhibition targeting BRD2/3/4 and selective inhibition of BRD4, as well as spleen tyrosine kinase (SYK) inhibition, are currently evaluated as haematologic cancer therapy. Herein, we characterized the differences in the biologic response of isoform-specific or pan-BET inhibition alone or in combination with SYK inhibition. MATERIALS AND METHODS: I-BET151 (pan-inhibitor) and AZD5153 (BRD4 inhibitor) were combined with Entospletinib (SYK inhibitor) and comparatively analysed in the canine DLBCL cell line CLBL-1. Dose- and time-dependent cellular responses were analysed by cell number, metabolic activity, apoptosis/necrosis, and cell morphology. The synergistic potential was evaluated through the Bliss independence model. RESULTS: I-BET151 and AZD5153 showed significant dose- and time-dependent inhibitory effects. Adding Entospletinib to I-BET151 or AZD5153 had no additional synergistic effects. CONCLUSION: Entospletinib did not enhance the inhibitory effects of the pan- or isoform-specific BET.


Assuntos
Indazóis/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Nucleares/antagonistas & inibidores , Isoformas de Proteínas/antagonistas & inibidores , Pirazinas/farmacologia , Animais , Linhagem Celular Tumoral , Cães , Compostos Heterocíclicos com 2 Anéis/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Linfoma Difuso de Grandes Células B/metabolismo , Piperazinas/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Quinase Syk/metabolismo
5.
Int J Med Sci ; 17(12): 1803-1810, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714083

RESUMO

Since the end of 2019, a new type of coronavirus pneumonia (COVID-19) caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been spreading rapidly throughout the world. Previously, there were two outbreaks of severe coronavirus caused by different coronaviruses worldwide, namely Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This article introduced the origin, virological characteristics and epidemiological overview of SARS-CoV-2, reviewed the currently known drugs that may prevent and treat coronavirus, explained the characteristics of the new coronavirus and provided novel information for the prevention and treatment of COVID-19.


Assuntos
Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Amidas/farmacologia , Amidas/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , Cloroquina/análogos & derivados , Cloroquina/uso terapêutico , Clorpromazina/uso terapêutico , Coronavirus/genética , Infecções por Coronavirus/genética , Ciclofilinas/antagonistas & inibidores , Desenvolvimento de Medicamentos , Reposicionamento de Medicamentos , Medicamentos de Ervas Chinesas/uso terapêutico , Endocitose/efeitos dos fármacos , Humanos , Soros Imunes , Indutores de Interferon/uso terapêutico , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Pneumonia Viral/genética , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Vacinas Virais/uso terapêutico
6.
J Nanosci Nanotechnol ; 20(12): 7311-7323, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711596

RESUMO

We started a study on the molecular docking of six potential pharmacologically active inhibitors compounds that can be used clinically against the COVID-19 virus, in this case, remdesivir, ribavirin, favipiravir, galidesivir, hydroxychloroquine and chloroquine interacting with the main COVID-19 protease in complex with a COVID-19 N3 protease inhibitor. The highest values of affinity energy found in order from highest to lowest were chloroquine (CHL), hydroxychloroquine (HYC), favipiravir (FAV), galidesivir (GAL), remdesivir (REM) and ribavirin (RIB). The possible formation of hydrogen bonds, associations through London forces and permanent electric dipole were analyzed. The values of affinity energy obtained for the hydroxychloroquine ligands was -9.9 kcal/mol and for the chloroquine of -10.8 kcal/mol which indicate that the coupling contributes to an effective improvement of the affinity energies with the protease. Indicating that, the position chosen to make the substitutions may be a pharmacophoric group, and cause changes in the protease.


Assuntos
Antivirais/química , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/enzimologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Cisteína Endopeptidases/química , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Adenina/administração & dosagem , Adenina/análogos & derivados , Adenina/química , Adenina/farmacologia , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/química , Monofosfato de Adenosina/farmacologia , Alanina/administração & dosagem , Alanina/análogos & derivados , Alanina/química , Alanina/farmacologia , Amidas/administração & dosagem , Amidas/química , Amidas/farmacologia , Antivirais/administração & dosagem , Sítios de Ligação , Cloroquina/administração & dosagem , Cloroquina/química , Cloroquina/farmacologia , Interações Medicamentosas , Humanos , Ligação de Hidrogênio , Hidroxicloroquina/administração & dosagem , Hidroxicloroquina/química , Hidroxicloroquina/farmacologia , Ligantes , Simulação de Acoplamento Molecular , Nanotecnologia , Pandemias , Inibidores de Proteases/administração & dosagem , Pirazinas/administração & dosagem , Pirazinas/química , Pirazinas/farmacologia , Pirrolidinas/administração & dosagem , Pirrolidinas/química , Pirrolidinas/farmacologia , Ribavirina/administração & dosagem , Ribavirina/química , Ribavirina/farmacologia , Eletricidade Estática
7.
Int J Mol Sci ; 21(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: covidwho-437471

RESUMO

The novel coronavirus, COVID-19, caused by SARS-CoV-2, is a global health pandemic that started in December 2019. The effective drug target among coronaviruses is the main protease Mpro, because of its essential role in processing the polyproteins that are translated from the viral RNA. In this study, the bioactivity of some selected heterocyclic drugs named Favipiravir (1), Amodiaquine (2), 2'-Fluoro-2'-deoxycytidine (3), and Ribavirin (4) was evaluated as inhibitors and nucleotide analogues for COVID-19 using computational modeling strategies. The density functional theory (DFT) calculations were performed to estimate the thermal parameters, dipole moment, polarizability, and molecular electrostatic potential of the present drugs; additionally, Mulliken atomic charges of the drugs as well as the chemical reactivity descriptors were investigated. The nominated drugs were docked on SARS-CoV-2 main protease (PDB: 6LU7) to evaluate the binding affinity of these drugs. Besides, the computations data of DFT the docking simulation studies was predicted that the Amodiaquine (2) has the least binding energy (-7.77 Kcal/mol) and might serve as a good inhibitor to SARS-CoV-2 comparable with the approved medicines, hydroxychloroquine, and remdesivir which have binding affinity -6.06 and -4.96 Kcal/mol, respectively. The high binding affinity of 2 was attributed to the presence of three hydrogen bonds along with different hydrophobic interactions between the drug and the critical amino acids residues of the receptor. Finally, the estimated molecular electrostatic potential results by DFT were used to illustrate the molecular docking findings. The DFT calculations showed that drug 2 has the highest of lying HOMO, electrophilicity index, basicity, and dipole moment. All these parameters could share with different extent to significantly affect the binding affinity of these drugs with the active protein sites.


Assuntos
Antivirais/farmacologia , Cisteína Endopeptidases/química , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/química , Amidas/química , Amidas/farmacologia , Amodiaquina/química , Amodiaquina/farmacologia , Antivirais/química , Sítios de Ligação , Cisteína Endopeptidases/metabolismo , Inibidores de Proteases/química , Ligação Proteica , Pirazinas/química , Pirazinas/farmacologia , Ribavirina/química , Ribavirina/farmacologia , Proteínas não Estruturais Virais/metabolismo
8.
Sci Immunol ; 5(48)2020 06 05.
Artigo em Inglês | MEDLINE | ID: covidwho-545978

RESUMO

Patients with severe COVID-19 have a hyperinflammatory immune response suggestive of macrophage activation. Bruton tyrosine kinase (BTK) regulates macrophage signaling and activation. Acalabrutinib, a selective BTK inhibitor, was administered off-label to 19 patients hospitalized with severe COVID-19 (11 on supplemental oxygen; 8 on mechanical ventilation), 18 of whom had increasing oxygen requirements at baseline. Over a 10-14 day treatment course, acalabrutinib improved oxygenation in a majority of patients, often within 1-3 days, and had no discernable toxicity. Measures of inflammation - C-reactive protein and IL-6 - normalized quickly in most patients, as did lymphopenia, in correlation with improved oxygenation. At the end of acalabrutinib treatment, 8/11 (72.7%) patients in the supplemental oxygen cohort had been discharged on room air, and 4/8 (50%) patients in the mechanical ventilation cohort had been successfully extubated, with 2/8 (25%) discharged on room air. Ex vivo analysis revealed significantly elevated BTK activity, as evidenced by autophosphorylation, and increased IL-6 production in blood monocytes from patients with severe COVID-19 compared with blood monocytes from healthy volunteers. These results suggest that targeting excessive host inflammation with a BTK inhibitor is a therapeutic strategy in severe COVID-19 and has led to a confirmatory international prospective randomized controlled clinical trial.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Tirosina Quinase da Agamaglobulinemia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Infecções por Coronavirus/virologia , Estado Terminal , Feminino , Seguimentos , Humanos , Inflamação/tratamento farmacológico , Inflamação/virologia , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Pandemias , Pneumonia Viral/virologia , Estudos Prospectivos , Respiração Artificial , Resultado do Tratamento
9.
Sci Immunol ; 5(48)2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503877

RESUMO

Patients with severe COVID-19 have a hyperinflammatory immune response suggestive of macrophage activation. Bruton tyrosine kinase (BTK) regulates macrophage signaling and activation. Acalabrutinib, a selective BTK inhibitor, was administered off-label to 19 patients hospitalized with severe COVID-19 (11 on supplemental oxygen; 8 on mechanical ventilation), 18 of whom had increasing oxygen requirements at baseline. Over a 10-14 day treatment course, acalabrutinib improved oxygenation in a majority of patients, often within 1-3 days, and had no discernable toxicity. Measures of inflammation - C-reactive protein and IL-6 - normalized quickly in most patients, as did lymphopenia, in correlation with improved oxygenation. At the end of acalabrutinib treatment, 8/11 (72.7%) patients in the supplemental oxygen cohort had been discharged on room air, and 4/8 (50%) patients in the mechanical ventilation cohort had been successfully extubated, with 2/8 (25%) discharged on room air. Ex vivo analysis revealed significantly elevated BTK activity, as evidenced by autophosphorylation, and increased IL-6 production in blood monocytes from patients with severe COVID-19 compared with blood monocytes from healthy volunteers. These results suggest that targeting excessive host inflammation with a BTK inhibitor is a therapeutic strategy in severe COVID-19 and has led to a confirmatory international prospective randomized controlled clinical trial.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Tirosina Quinase da Agamaglobulinemia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Infecções por Coronavirus/virologia , Estado Terminal , Feminino , Seguimentos , Humanos , Inflamação/tratamento farmacológico , Inflamação/virologia , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Pandemias , Pneumonia Viral/virologia , Estudos Prospectivos , Respiração Artificial , Resultado do Tratamento
10.
Int J Mol Sci ; 21(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486229

RESUMO

The novel coronavirus, COVID-19, caused by SARS-CoV-2, is a global health pandemic that started in December 2019. The effective drug target among coronaviruses is the main protease Mpro, because of its essential role in processing the polyproteins that are translated from the viral RNA. In this study, the bioactivity of some selected heterocyclic drugs named Favipiravir (1), Amodiaquine (2), 2'-Fluoro-2'-deoxycytidine (3), and Ribavirin (4) was evaluated as inhibitors and nucleotide analogues for COVID-19 using computational modeling strategies. The density functional theory (DFT) calculations were performed to estimate the thermal parameters, dipole moment, polarizability, and molecular electrostatic potential of the present drugs; additionally, Mulliken atomic charges of the drugs as well as the chemical reactivity descriptors were investigated. The nominated drugs were docked on SARS-CoV-2 main protease (PDB: 6LU7) to evaluate the binding affinity of these drugs. Besides, the computations data of DFT the docking simulation studies was predicted that the Amodiaquine (2) has the least binding energy (-7.77 Kcal/mol) and might serve as a good inhibitor to SARS-CoV-2 comparable with the approved medicines, hydroxychloroquine, and remdesivir which have binding affinity -6.06 and -4.96 Kcal/mol, respectively. The high binding affinity of 2 was attributed to the presence of three hydrogen bonds along with different hydrophobic interactions between the drug and the critical amino acids residues of the receptor. Finally, the estimated molecular electrostatic potential results by DFT were used to illustrate the molecular docking findings. The DFT calculations showed that drug 2 has the highest of lying HOMO, electrophilicity index, basicity, and dipole moment. All these parameters could share with different extent to significantly affect the binding affinity of these drugs with the active protein sites.


Assuntos
Antivirais/farmacologia , Cisteína Endopeptidases/química , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/química , Amidas/química , Amidas/farmacologia , Amodiaquina/química , Amodiaquina/farmacologia , Antivirais/química , Sítios de Ligação , Cisteína Endopeptidases/metabolismo , Inibidores de Proteases/química , Ligação Proteica , Pirazinas/química , Pirazinas/farmacologia , Ribavirina/química , Ribavirina/farmacologia , Proteínas não Estruturais Virais/metabolismo
11.
PLoS Negl Trop Dis ; 14(6): e0008283, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32497085

RESUMO

BACKGROUND: The Crimean-Congo hemorrhagic fever virus (CCHFV) is a segmented negative-sense RNA virus that can cause severe human disease. The World Health Organization (WHO) has listed CCHFVas a priority pathogen with an urgent need for enhanced research activities to develop effective countermeasures. Here we adopted a biochemical approach that targets the viral RNA-dependent RNA polymerase (RdRp). The CCHFV RdRp activity is part of a multifunctional L protein that is unusually large with a molecular weight of ~450 kDa. The CCHFV L-protein also contains an ovarian tumor (OTU) domain that exhibits deubiquitinating (DUB) activity, which was shown to interfere with innate immune responses and viral replication. We report on the expression, characterization and inhibition of the CCHFV full-length L-protein and studied both RNA synthesis and DUB activity. METHODOLOGY/PRINCIPLE FINDINGS: Recombinant full-length CCHFV L protein was expressed in insect cells and purified to near homogeneity using affinity chromatography. RdRp activity was monitored with model primer/templates during elongation in the presence of divalent metal ions. We observed a 14-mer full length RNA product as well as the expected shorter products when omitting certain nucleotides from the reaction mixture. The D2517N mutation of the putative active site rendered the enzyme inactive. Inhibition of RNA synthesis was studies with the broad-spectrum antivirals ribavirin and favipiravir that mimic nucleotide substrates. The triphosphate form of these compounds act like ATP or GTP; however, incorporation of ATP or GTP is markedly favored over the inhibitors. We also studied the effects of bona fide nucleotide analogues 2'-deoxy-2'-fluoro-CTP (FdC) and 2'-deoxy-2'-amino-CTP and demonstrate increased inhibitory effects due to higher rates of incorporation. We further show that the CCHFV L full-length protein and the isolated OTU domain cleave Lys48- and Lys63-linked polyubiqutin chains. Moreover, the ubiquitin analogue CC.4 inhibits the CCHFV-associated DUB activity of the full-length L protein and the isolated DUB domain to a similar extent. Inhibition of DUB activity does not affect elongation of RNA synthesis, and inhibition of RNA synthesis does not affect DUB activity. Both domains are functionally independent under these conditions. CONCLUSIONS/SIGNIFICANCE: The requirements for high biosafety measures hamper drug discovery and development efforts with infectious CCHFV. The availability of full-length CCHFV L-protein provides an important tool in this regard. High-throughput screening (HTS) campaigns are now feasible. The same enzyme preparations can be employed to identify novel polymerase and DUB inhibitors.


Assuntos
RNA Polimerases Dirigidas por DNA/fisiologia , Enzimas Desubiquitinantes/fisiologia , Vírus da Febre Hemorrágica da Crimeia-Congo/enzimologia , Replicação Viral/efeitos dos fármacos , Amidas/farmacologia , Vírus da Febre Hemorrágica da Crimeia-Congo/fisiologia , Febre Hemorrágica da Crimeia/virologia , Humanos , Mutação , Estrutura Terciária de Proteína , Pirazinas/farmacologia , RNA Viral , Ribavirina/farmacologia
12.
Am J Chin Med ; 48(4): 945-966, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32476431

RESUMO

Tetramethylpyrazine has shown neuroprotective and axonal outgrowth-promoting effects and can improve cognitive deficit in a rat model of chronic hypoperfusion. However, the role of tetramethylpyrazine in sevoflurane-induced neurotoxicity is still vague. Therefore, this study was designed to investigate the effects and mechanisms of tetramethylpyrazine on sevoflurane-induced autophagy, apoptosis, and the expression of BACE1 and A[Formula: see text] in SH-SY5Y cells. We measured the expression levels of the apoptosis protein markers Bax and Bcl-2, autophagy protein markers Atg5 and LC3-II, BACE1, and A[Formula: see text] in SH-SY5Y cells after sevoflurane treatment and determined the effects of tetramethylpyrazine on sevoflurane-induced expression of these proteins after silencing GPR50 or Atg5 with siRNA in vitro. We found that exposure to 3.4% sevoflurane for 6 h decreased the expression of autophagy protein markers and increased the expression of the apoptosis protein markers, BACE1, and A[Formula: see text] in SH-SY5Y cells. The number of red puncta (autolysosomes) and yellow puncta (autophagosomes) in each SH-SY5Y cell decreased after transient transfection with the mRFP-GFP-LC3 expression plasmid. Silencing of GPR50 decreased the expression of pCREB, Atg5, and LC3-II, while silencing of Atg5 increased the expression of BACE1 and A[Formula: see text] in SH-SY5Y cells. Our results demonstrate that tetramethylpyrazine attenuated sevoflurane-induced neurotoxicity by enhancing autophagy through the GPR50/CREB pathway in SH-SY5Y cells.


Assuntos
Autofagia/efeitos dos fármacos , Autofagia/genética , Proteína de Ligação a CREB/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuroprostanos , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Receptores Acoplados a Proteínas-G/metabolismo , Sevoflurano/toxicidade , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Células Tumorais Cultivadas
13.
PLoS One ; 15(6): e0234484, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511271

RESUMO

Inflammation plays a crucial role in the defense response of the innate immune system against pathogen infection. In this study, we selected 4 compounds for their potential or proven anti-inflammatory and/or anti-microbial properties to test on our in vitro model of bacteria-infected THP-1-derived macrophages. We first compared the capacity of sulforaphane (SFN), wogonin (WG), oltipraz (OTZ), and dimethyl fumarate (DMF) to induce the nuclear factor erythroid 2-related factor 2 (Nrf2), a key regulator of the antioxidant, anti-inflammatory response pathways. Next, we performed a comparative evaluation of the antioxidant and anti-inflammatory efficacies of the 4 selected compounds. THP-1-derived macrophages and LPS-stimulated macrophages were treated with each compound and expression levels of genes coding for inflammatory cytokines IL-1ß, IL-6, and TNF-α were quantified by RT-qPCR. Moreover, expression levels of genes coding for M1 (IL-23, CCR7, IL-1ß, IL-6, and TNF-α) and M2 (PPARγ, MRC1, CCL22, and IL-10) markers were determined in classically-activated M1 macrophages treated with each compound. Finally, the effects of each compound on the intracellular bacterial survival of gram-negative E. coli and gram-positive S. aureus in THP-1-derived macrophages and PBMC-derived macrophages were examined. Our data confirmed the anti-inflammatory and antioxidant effects of SFN, WG, and DMF on LPS-stimulated THP-1-derived macrophages. In addition, SFN or WG treatment of classically-activated THP-1-derived macrophages reduced expression levels of M1 marker genes, while SFN or DMF treatment upregulated the M2 marker gene MRC1. This decrease in expression of M1 marker genes may be correlated with the decrease in intracellular S. aureus load in SFN- or DMF-treated macrophages. Interestingly, an increase in intracellular survival of E. coli in SFN-treated THP-1-derived macrophages that was not observed in PBMC-derived macrophages. Conversely, OTZ exhibited pro-oxidant and proinflammatory properties, and affected intracellular survival of E. coli in THP-1-derived macrophages. Altogether, we provide new potential therapeutic alternatives in treating inflammation and bacterial infection.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Inflamação/tratamento farmacológico , Ativação de Macrófagos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/imunologia , Estresse Oxidativo/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Fumarato de Dimetilo/farmacologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/imunologia , Flavanonas/farmacologia , Humanos , Inflamação/imunologia , Isotiocianatos/farmacologia , Leucócitos Mononucleares , Ativação de Macrófagos/imunologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Estresse Oxidativo/imunologia , Pirazinas/farmacologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/efeitos dos fármacos , Células THP-1
14.
Eur Heart J Acute Cardiovasc Care ; 9(3): 209-214, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: covidwho-165340

RESUMO

Therapeutic options for coronavirus disease 2019 are desperately needed to respond to the ongoing severe acute respiratory syndrome coronavirus 2 pandemic. Both antiviral drugs and immunomodulators might have their place in the management of coronavirus disease 2019. Unfortunately, no drugs have been approved yet to treat infections with human coronaviruses. As it will take years to develop new therapies for severe acute respiratory syndrome coronavirus 2, the current focus is on the repurposing of drugs that have been approved or are in development for other conditions. Several clinical trials have already been conducted or are currently ongoing to evaluate the efficacy of such drugs. Here, we discuss the potential of these therapies for the treatment of coronavirus disease 2019.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Betacoronavirus/efeitos dos fármacos , Cloroquina/toxicidade , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Administração Intravenosa , Alanina/administração & dosagem , Alanina/farmacologia , Alanina/uso terapêutico , Amidas/farmacologia , Amidas/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antivirais/administração & dosagem , Antivirais/farmacologia , Antivirais/uso terapêutico , Cloroquina/efeitos adversos , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Inibidores do Citocromo P-450 CYP3A/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Fatores Imunológicos/uso terapêutico , Lopinavir/farmacologia , Lopinavir/uso terapêutico , Pandemias , Pneumonia Viral/epidemiologia , Pirazinas/farmacologia , Pirazinas/uso terapêutico , RNA Viral/efeitos dos fármacos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico
15.
Eur Heart J Acute Cardiovasc Care ; 9(3): 209-214, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32363880

RESUMO

Therapeutic options for coronavirus disease 2019 are desperately needed to respond to the ongoing severe acute respiratory syndrome coronavirus 2 pandemic. Both antiviral drugs and immunomodulators might have their place in the management of coronavirus disease 2019. Unfortunately, no drugs have been approved yet to treat infections with human coronaviruses. As it will take years to develop new therapies for severe acute respiratory syndrome coronavirus 2, the current focus is on the repurposing of drugs that have been approved or are in development for other conditions. Several clinical trials have already been conducted or are currently ongoing to evaluate the efficacy of such drugs. Here, we discuss the potential of these therapies for the treatment of coronavirus disease 2019.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Betacoronavirus/efeitos dos fármacos , Cloroquina/toxicidade , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Administração Intravenosa , Alanina/administração & dosagem , Alanina/farmacologia , Alanina/uso terapêutico , Amidas/farmacologia , Amidas/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antivirais/administração & dosagem , Antivirais/farmacologia , Antivirais/uso terapêutico , Cloroquina/efeitos adversos , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Inibidores do Citocromo P-450 CYP3A/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Fatores Imunológicos/uso terapêutico , Lopinavir/farmacologia , Lopinavir/uso terapêutico , Pandemias , Pneumonia Viral/epidemiologia , Pirazinas/farmacologia , Pirazinas/uso terapêutico , RNA Viral/efeitos dos fármacos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico
18.
Med Oncol ; 37(5): 47, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32277292

RESUMO

Pancreatic cancer is a highly progressive malignant tumor for which there is a critical unmet need for novel therapeutic strategies. A previous study of the authors indicated that VE-821, a selective inhibitor of the ataxia-telangiectasia-mutated and rad3-related protein (ATR), has antitumor efficacy. In this study, the effect of programmed death ligand 1 (PD-L1) on the sensitivity to VE-821 was investigated in p53 mutant pancreatic cancer cells. These results show that BxPC-3 cells exhibited higher sensitivity to VE-821 than mesenchymal PANC-1 cells, which were more migratory and had higher expressions of PD-L1 and CD44. When VE-821 was applied to two cells, epithelial-to-mesenchymal transition (EMT) was induced in PANC-1 cells with concomitant upregulation of PD-L1 and CD44, while BxPC-3 cells did not manifest these changes. Attenuation of PD-L1 expression suppressed VE-821-induced EMT, inhibited cell migration, and downregulated CD44 expression. Furthermore, PD-L1 inhibition partially reversed the activation of AKT/ERK, enhanced DNA damage, and increased VE-821 sensitivity in PANC-1 cells. Analysis of GEPIA data showed positive correlation of PD-L1 expression with EMT-related transcription factors. Taken together, these results suggest a novel function of PD-L1 in regulating response to ATR inhibition. These data highlight PD-L1 inhibition as a promising target to enhance sensitivity to ATR inhibitors in mesenchymal pancreatic cancer.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Antígeno B7-H1/genética , Transição Epitelial-Mesenquimal , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Antineoplásicos/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Técnicas de Silenciamento de Genes , Humanos , Receptores de Hialuronatos/genética , Neoplasias Pancreáticas/metabolismo , Pirazinas/farmacologia , Sulfonas/farmacologia , Proteína Supressora de Tumor p53/deficiência , Regulação para Cima/efeitos dos fármacos
19.
Antiviral Res ; 178: 104786, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32251767

RESUMO

An escalating pandemic by the novel SARS-CoV-2 virus is impacting global health and effective therapeutic options are urgently needed. We evaluated the in vitro antiviral effect of compounds that were previously reported to inhibit coronavirus replication and compounds that are currently under evaluation in clinical trials for SARS-CoV-2 patients. We report the antiviral effect of remdesivir, lopinavir, homorringtonine, and emetine against SARS-CoV-2 virus in Vero E6 cells with the estimated 50% effective concentration at 23.15 µM, 26.63 µM, 2.55 µM and 0.46 µM, respectively. Ribavirin or favipiravir that are currently evaluated under clinical trials showed no inhibition at 100 µM. Synergy between remdesivir and emetine was observed, and remdesivir at 6.25 µM in combination with emetine at 0.195 µM may achieve 64.9% inhibition in viral yield. Combinational therapy may help to reduce the effective concentration of compounds below the therapeutic plasma concentrations and provide better clinical benefits.


Assuntos
Antimetabólitos/farmacologia , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Emetina/farmacologia , Mepesuccinato de Omacetaxina/farmacologia , Lopinavir/farmacologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Replicação Viral/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Amidas/farmacologia , Animais , Betacoronavirus/fisiologia , Chlorocebus aethiops , Combinação de Medicamentos , Células Epiteliais , Humanos , Pandemias , Pirazinas/farmacologia , Ribavirina/farmacologia , Células Vero
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