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1.
Science ; 368(6492): 779-782, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32277040

RESUMO

A novel coronavirus [severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)] outbreak has caused a global coronavirus disease 2019 (COVID-19) pandemic, resulting in tens of thousands of infections and thousands of deaths worldwide. The RNA-dependent RNA polymerase [(RdRp), also named nsp12] is the central component of coronaviral replication and transcription machinery, and it appears to be a primary target for the antiviral drug remdesivir. We report the cryo-electron microscopy structure of COVID-19 virus full-length nsp12 in complex with cofactors nsp7 and nsp8 at 2.9-angstrom resolution. In addition to the conserved architecture of the polymerase core of the viral polymerase family, nsp12 possesses a newly identified ß-hairpin domain at its N terminus. A comparative analysis model shows how remdesivir binds to this polymerase. The structure provides a basis for the design of new antiviral therapeutics that target viral RdRp.


Assuntos
Betacoronavirus/enzimologia , RNA Replicase/química , RNA Replicase/ultraestrutura , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/ultraestrutura , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/metabolismo , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/metabolismo , Alanina/farmacologia , Antivirais/metabolismo , Antivirais/farmacologia , Domínio Catalítico , Microscopia Crioeletrônica , Desenho de Fármacos , Modelos Moleculares , Conformação Proteica em Folha beta , Domínios Proteicos , RNA Replicase/antagonistas & inibidores , RNA Replicase/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
2.
Life Sci ; 248: 117477, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32119961

RESUMO

AIMS: A newly emerged Human Coronavirus (HCoV) is reported two months ago in Wuhan, China (COVID-19). Until today >2700 deaths from the 80,000 confirmed cases reported mainly in China and 40 other countries. Human to human transmission is confirmed for COVID-19 by China a month ago. Based on the World Health Organization (WHO) reports, SARS HCoV is responsible for >8000 cases with confirmed 774 deaths. Additionally, MERS HCoV is responsible for 858 deaths out of about 2500 reported cases. The current study aims to test anti-HCV drugs against COVID-19 RNA dependent RNA polymerase (RdRp). MATERIALS AND METHODS: In this study, sequence analysis, modeling, and docking are used to build a model for Wuhan COVID-19 RdRp. Additionally, the newly emerged Wuhan HCoV RdRp model is targeted by anti-polymerase drugs, including the approved drugs Sofosbuvir and Ribavirin. KEY FINDINGS: The results suggest the effectiveness of Sofosbuvir, IDX-184, Ribavirin, and Remidisvir as potent drugs against the newly emerged HCoV disease. SIGNIFICANCE: The present study presents a perfect model for COVID-19 RdRp enabling its testing in silico against anti-polymerase drugs. Besides, the study presents some drugs that previously proved its efficiency against the newly emerged viral infection.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/química , Betacoronavirus/enzimologia , Infecções por Coronavirus/tratamento farmacológico , Guanosina Monofosfato/análogos & derivados , Pneumonia Viral/tratamento farmacológico , RNA Replicase/antagonistas & inibidores , Ribavirina/química , Sofosbuvir/química , Proteínas Virais/antagonistas & inibidores , Monofosfato de Adenosina/química , Monofosfato de Adenosina/metabolismo , Alanina/química , Alanina/metabolismo , Alphacoronavirus/enzimologia , Alphacoronavirus/genética , Sequência de Aminoácidos , Antivirais/metabolismo , Betacoronavirus/genética , Domínio Catalítico , Biologia Computacional/métodos , Infecções por Coronavirus/virologia , Reposicionamento de Medicamentos/métodos , Guanosina Monofosfato/química , Guanosina Monofosfato/metabolismo , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Humanos , Simulação de Acoplamento Molecular , Pneumonia Viral/virologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , RNA Replicase/química , RNA Replicase/metabolismo , Ribavirina/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sofosbuvir/metabolismo , Termodinâmica , Uridina Trifosfato/química , Uridina Trifosfato/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo
3.
Science ; 368(6489): 409-412, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32198291

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a global health emergency. An attractive drug target among coronaviruses is the main protease (Mpro, also called 3CLpro) because of its essential role in processing the polyproteins that are translated from the viral RNA. We report the x-ray structures of the unliganded SARS-CoV-2 Mpro and its complex with an α-ketoamide inhibitor. This was derived from a previously designed inhibitor but with the P3-P2 amide bond incorporated into a pyridone ring to enhance the half-life of the compound in plasma. On the basis of the unliganded structure, we developed the lead compound into a potent inhibitor of the SARS-CoV-2 Mpro The pharmacokinetic characterization of the optimized inhibitor reveals a pronounced lung tropism and suitability for administration by the inhalative route.


Assuntos
Amidas/química , Amidas/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/enzimologia , Cisteína Endopeptidases/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/química , Amidas/metabolismo , Animais , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacocinética , Antivirais/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Cisteína Endopeptidases/metabolismo , Desenho de Fármacos , Meia-Vida , Humanos , Pulmão/metabolismo , Camundongos , Modelos Moleculares , Inibidores de Proteases/metabolismo , Inibidores de Proteases/farmacocinética , Domínios Proteicos , Multimerização Proteica , Piridonas/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
4.
Viruses ; 12(2)2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098094

RESUMO

Porcine epidemic diarrhea virus (PEDV), being highly virulent and contagious in piglets, has caused significant damage to the pork industries of many countries worldwide. There are no commercial drugs targeting coronaviruses (CoVs), and few studies on anti-PEDV inhibitors. The coronavirus 3C-like protease (3CLpro) has a conserved structure and catalytic mechanism and plays a key role during viral polyprotein processing, thus serving as an appealing antiviral drug target. Here, we report the anti-PEDV effect of the broad-spectrum inhibitor GC376 (targeting 3Cpro or 3CLpro of viruses in the picornavirus-like supercluster). GC376 was highly effective against the PEDV 3CLpro and exerted similar inhibitory effects on two PEDV strains. Furthermore, the structure of the PEDV 3CLpro in complex with GC376 was determined at 1.65 Å. We elucidated structural details and analyzed the differences between GC376 binding with the PEDV 3CLpro and GC376 binding with the transmissible gastroenteritis virus (TGEV) 3CLpro. Finally, we explored the substrate specificity of PEDV 3CLpro at the P2 site and analyzed the effects of Leu group modification in GC376 on inhibiting PEDV infection. This study helps us to understand better the PEDV 3CLpro substrate specificity, providing information on the optimization of GC376 for development as an antiviral therapeutic against coronaviruses.


Assuntos
Antivirais/farmacologia , Peptídeo Hidrolases/química , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Pirrolidinas/farmacologia , Animais , Antivirais/química , Antivirais/metabolismo , Domínio Catalítico , Chlorocebus aethiops , Cristalografia por Raios X , Modelos Moleculares , Peptídeo Hidrolases/metabolismo , Vírus da Diarreia Epidêmica Suína/enzimologia , Vírus da Diarreia Epidêmica Suína/fisiologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Pirrolidinas/química , Pirrolidinas/metabolismo , Especificidade por Substrato , Vírus da Gastroenterite Transmissível/enzimologia , Células Vero , Replicação Viral/efeitos dos fármacos
5.
PLoS One ; 15(1): e0227104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31914458

RESUMO

Despite the availability of highly effective direct-acting antiviral (DAA) regimens for the treatment of hepatitis C virus (HCV) infections, sustained viral response (SVR) rates remain suboptimal for difficult-to-treat patient populations such as those with HCV genotype 3, cirrhosis or prior treatment experience, warranting development of more potent HCV replication antivirals. AT-527 is the hemi-sulfate salt of AT-511, a novel phosphoramidate prodrug of 2'-fluoro-2'-C-methylguanosine-5'-monophosphate that has potent in vitro activity against HCV. The EC50 of AT-511, determined using HCV laboratory strains and clinical isolates with genotypes 1-5, ranged from 5-28 nM. The active 5'-triphosphate metabolite, AT-9010, specifically inhibited the HCV RNA-dependent RNA polymerase. AT-511 did not inhibit the replication of other selected RNA or DNA viruses in vitro. AT-511 was approximately 10-fold more active than sofosbuvir (SOF) against a panel of laboratory strains and clinical isolates of HCV genotypes 1-5 and remained fully active against S282T resistance-associated variants, with up to 58-fold more potency than SOF. In vitro, AT-511 did not inhibit human DNA polymerases or elicit cytotoxicity or mitochondrial toxicity at concentrations up to 100 µM. Unlike the other potent guanosine analogs PSI-938 and PSI-661, no mutagenic O6-alkylguanine bases were formed when incubated with cytochrome P450 (CYP) 3A4, and AT-511 had IC50 values ≥25 µM against a panel of CYP enzymes. In hepatocytes from multiple species, the active triphosphate was the predominant metabolite produced from the prodrug, with a half-life of 10 h in human hepatocytes. When given orally to rats and monkeys, AT-527 preferentially delivered high levels of AT-9010 in the liver in vivo. These favorable preclinical attributes support the ongoing clinical development of AT-527 and suggest that, when used in combination with an HCV DAA from a different class, AT-527 may increase SVR rates, especially for difficult-to-treat patient populations, and could potentially shorten treatment duration for all patients.


Assuntos
Antivirais/farmacologia , Guanosina/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Pró-Fármacos/farmacologia , Animais , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacocinética , Linhagem Celular , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Feminino , Guanosina/análogos & derivados , Guanosina/metabolismo , Guanosina/farmacocinética , Haplorrinos , Hepacivirus/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/virologia , Humanos , Masculino , Camundongos , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacocinética , Ratos
6.
PLoS Pathog ; 16(1): e1008215, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31899788

RESUMO

CREB-binding protein (CBP) participates in numerous transcription events. However, cell-intrinsic inhibitors of CBP are poorly defined. Here, we found that cellular USP12 interacts with the HAT domain of CBP and inhibits CBP's acetyltransferase activity. Interestingly, USP12 positively regulates interferon (IFN) antiviral signaling independently of its deubiquitinase activity. Furthermore, we found that in IFN signaling USP12 translocates from the cytoplasm to the nucleus. The decrease in cytoplasmic USP12 facilitates CBP-induced acetylation and activation of IFN signaling proteins in the cytoplasm. Moreover, USP12 accumulation in the nucleus blocks CBP-induced acetylation of phosphorylated STAT1 (p-STAT1) and therefore inhibits the dephosphorylation effects of TCPTP on p-STAT1, which finally maintains nuclear p-STAT1 levels and IFN antiviral efficacy. USP12 nuclear translocation extends our understanding of the regulation of the strength of IFN antiviral signaling. Our study uncovers a cell-intrinsic regulation of CBP acetyltransferase activity and may provide potential strategies for IFN-based antiviral therapy.


Assuntos
Proteína de Ligação a CREB/antagonistas & inibidores , Interferons/fisiologia , Ubiquitina Tiolesterase/metabolismo , Acetilação , Animais , Antivirais/metabolismo , Proteína de Ligação a CREB/metabolismo , Citoplasma/metabolismo , Inibidores Enzimáticos/metabolismo , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Domínios Proteicos , Células RAW 264.7 , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
7.
Gene ; 729: 144300, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31884102

RESUMO

West Nile virus (WNV) has been found to be a common cause of neuroinvasive arboviral disease worldwide in human and horses. The process of RNA interference induced by small RNA molecules, like small interfering RNA (siRNA) and microRNA (miRNA), proved to be a novel approach for preventing viral infections. So far there is no published data for inhibition of West Nile virus by vector delivered artificial miRNA which believed to have more inhibitory potential than small interfering (siRNA). In the present study, we designed two artificial miRNA (amiRNAs) targeting the conserved NS5 and NS2A genomic regions of West Nile virus. These amiRNAs oligos were cloned in to miRNA based vector having murine miR-155 backbone which allows the high expression of amiRNAs in green fluorescent protein (GFP) tagged form. Vero cells were transiently transfected by cytomegalovirus (CMV) promoter derived vector expressing amiRNAs transcribed by RNA Pol II. Efficacy of amiRNA targeting the NS5 and NS2A regions of WNV was determined in highly virulent WNV Eg101 strain in Vero cells. The result indicated that both amiRNA effectively inhibit West Nile virus replication. The concatenated amiRNA having dual pre-amiRNA expression cassette showed better efficacy. amiRNA targeting NS5 showed best protection against WNV infection and percentage reduction of WNV titer was observed at 96 hpi is 97.11%. Further study for inhibition of WNV replication was assessed by plaque assay, quantitative reverse transcriptase PCR (qRT-PCR) assay, Immunofluorescence assay and Western blot analysis. Present study concludes that amiRNA (NS5) targeting conserved region of gene significantly reduced the virus replication as determined by plaque assay. Similarly, reduction was also observed at RNA and protein level through real-time RT-PCR and Western blot analysis directly correlate with the inhibition of WNV replication. Here, we describe our current understanding of the role of miRNAs in host defense response against West Nile virus, as well as their potential as new therapeutic approaches.


Assuntos
Replicação Viral/genética , Febre do Nilo Ocidental/prevenção & controle , Vírus do Nilo Ocidental/genética , Animais , Antivirais/metabolismo , Chlorocebus aethiops , Engenharia Genética/métodos , MicroRNAs/biossíntese , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Células Vero , Febre do Nilo Ocidental/genética , Vírus do Nilo Ocidental/patogenicidade
8.
Comput Biol Chem ; 84: 107167, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31855781

RESUMO

BACKGROUND: Hepatitis C Virus (HCV) infection is a major public health concern across the globe. At present, direct-acting antivirals are the treatment of choice. However, the long-term effect of this therapy has yet to be ascertained. Previously, fluoroquinolones have been reported to inhibit HCV replication by targeting NS3 protein. Therefore, it is logical to hypothesize that the natural analogs of fluoroquinolones will exhibit NS3 inhibitory activity with substantially lesser side effects. METHOD: In this study, we tested the application of a recently devised integrated in-silico Cheminformatics-Molecular Docking approach to identify physicochemically similar natural analogs of fluoroquinolones from the available databases (Ambinter, Analyticon, Indofines, Specs, and TimTec). Molecular docking and ROC curve analyses were performed, using PatchDock and Graphpad software, respectively, to compare and analyze drug-protein interactions between active natural analogs, Fluoroquinolones, and HCV NS3 protein. RESULT: In our analysis, we were able to shortlist 18 active natural analogs, out of 10,399, that shared physicochemical properties with the template drugs (fluoroquinolones). These analogs showed comparable binding efficacy with fluoroquinolones in targeting 32 amino acids in the HCV NS3 active site that are crucial for NS3 activity. Our approach had around 80 % sensitivity and 70 % specificity in identifying physicochemically similar analogs of fluoroquinolones. CONCLUSION: Our current data suggest that our approach can be efficiently applied to identify putative HCV drug inhibitors that can be taken for in vitro testing. This approach can be applied to discover physicochemically similar analogs of virtually any drug, thus providing a speedy and inexpensive approach to complement drug discovery and design, which can tremendously economize on time and money spent on the screening of putative drugs.


Assuntos
Antivirais/metabolismo , Descoberta de Drogas/métodos , Inibidores Enzimáticos/metabolismo , Fluoroquinolonas/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Domínio Catalítico , Quimioinformática , Inibidores Enzimáticos/química , Fluoroquinolonas/química , Hepacivirus/enzimologia , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
9.
BMC Complement Altern Med ; 19(1): 346, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791311

RESUMO

BACKGROUND: Influenza A virus (IAV) is still a major health threat. The clinical manifestations of this infection are related to immune dysregulation, which causes morbidity and mortality. The usage of traditional medication with immunomodulatory properties against influenza infection has been increased recently. Our previous study showed antiviral activity of quercetin-3-O-α-L-rhamnopyranoside (Q3R) isolated from Rapanea melanophloeos (RM) (L.) Mez (family Myrsinaceae) against H1N1 (A/PR/8/34) infection. This study aimed to confirm the wider range of immunomodulatory effect of Q3R on selective pro- and anti-inflammatory cytokines against IAV in vitro, to evaluate the effect of Q3R on apoptosis pathway in combination with H1N1, also to assess the physical interaction of Q3R with virus glycoproteins and RhoA protein using computational docking. METHODS: MDCK cells were exposed to Q3R and 100CCID50/100 µl of H1N1 in combined treatments (co-, pre- and post-penetration treatments). The treatments were tested for the cytokines evaluation at RNA and protein levels by qPCR and ELISA, respectively. In another set of treatment, apoptosis was examined by detecting RhoA GTPase protein and caspase-3 activity. Molecular docking was used as a tool for evaluation of the potential anti-influenza activity of Q3R. RESULTS: The expressions of cytokines in both genome and protein levels were significantly affected by Q3R treatment. It was shown that Q3R was much more effective against influenza when it was applied in co-penetration treatment. Q3R in combination with H1N1 increased caspase-3 activity while decreasing RhoA activation. The molecular docking results showed strong binding ability of Q3R with M2 transmembrane, Neuraminidase of 2009 pandemic H1N1, N1 and H1 of PR/8/1934 and Human RhoA proteins, with docking energy of - 10.81, - 10.47, - 9.52, - 9.24 and - 8.78 Kcal/mol, respectively. CONCLUSIONS: Quercetin-3-O-α-L-rhamnopyranoside from RM was significantly effective against influenza infection by immunomodulatory properties, affecting the apoptosis pathway and binding ability to viral receptors M2 transmembrane and Neuraminidase of 2009 pandemic H1N1 and human RhoA cellular protein. Further research will focus on detecting the detailed specific mechanism of Q3R in virus-host interactions.


Assuntos
Antivirais , Glicosídeos , Vírus da Influenza A Subtipo H1N1 , Myrsine/química , Compostos Fitoquímicos , Quercetina/análogos & derivados , Animais , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Cães , Glicosídeos/química , Glicosídeos/metabolismo , Glicosídeos/farmacologia , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , Neuraminidase/química , Neuraminidase/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Quercetina/química , Quercetina/metabolismo , Quercetina/farmacologia , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/metabolismo
10.
PLoS Negl Trop Dis ; 13(12): e0007419, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830030

RESUMO

Despite Nipah virus outbreaks having high mortality rates (>70% in Southeast Asia), there are no licensed drugs against it. In this study, we have considered all 9 Nipah proteins as potential therapeutic targets and computationally identified 4 putative peptide inhibitors (against G, F and M proteins) and 146 small molecule inhibitors (against F, G, M, N, and P proteins). The computations include extensive homology/ab initio modeling, peptide design and small molecule docking. An important contribution of this study is the increased structural characterization of Nipah proteins by approximately 90% of what is deposited in the PDB. In addition, we have carried out molecular dynamics simulations on all the designed protein-peptide complexes and on 13 of the top shortlisted small molecule ligands to check for stability and to estimate binding strengths. Details, including atomic coordinates of all the proteins and their ligand bound complexes, can be accessed at http://cospi.iiserpune.ac.in/Nipah. Our strategy was to tackle the development of therapeutics on a proteome wide scale and the lead compounds identified could be attractive starting points for drug development. To counter the threat of drug resistance, we have analysed the sequences of the viral strains from different outbreaks, to check whether they would be sensitive to the binding of the proposed inhibitors.


Assuntos
Antivirais/isolamento & purificação , Antivirais/farmacologia , Vírus Nipah/efeitos dos fármacos , Proteínas Virais/antagonistas & inibidores , Antivirais/química , Antivirais/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Proteínas Virais/química
11.
Biomed Res Int ; 2019: 3947245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886207

RESUMO

Zika flavivirus is suspected to cause Guillain-Barre syndrome in adults and microcephaly, along with other congenital abnormalities in infants. Presently, no vaccines or therapeutics are available. Here, we report novel compounds identified by high-throughput virtual screening of Maybridge chemical database and molecular docking studies. We selected viral enzyme NS2B/NS3 serine protease as the therapeutic target because of its important role in viral replication. We selected seven potential compounds as antiviral drug candidates because of their high GOLD fitness score, high AutoDock Vina score, or X-Score binding energy and analyzed the strength of molecular interactions between the active site amino acids and selected compounds. Our study also provides a foundation for similar studies for the search of novel therapeutics against Zika virus.


Assuntos
Antivirais , Peptídeo Hidrolases , Proteínas não Estruturais Virais , Proteínas Virais , Zika virus/química , Aminoácidos/química , Aminoácidos/metabolismo , Antivirais/química , Antivirais/metabolismo , Descoberta de Drogas , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Ligação Proteica , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo
12.
Curr Top Med Chem ; 19(31): 2868-2918, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31724505

RESUMO

Actinomycetes is an abundant resource for discovering a large number of lead compounds, which play an important role in microbial drug discovery. Compared to terrestrial microorganisms, marine actinomycetes have unique metabolic pathways because of their special living environment, which has the potential to produce a variety of bioactive substances. In this paper, secondary metabolites isolated from marine actinomycetes are reviewed (2013-2018), most of which exhibited cytotoxic, antibacterial, and antiviral biological activities.


Assuntos
Actinobacteria/química , Antibacterianos/metabolismo , Antineoplásicos/metabolismo , Antivirais/metabolismo , Produtos Biológicos/metabolismo , Actinobacteria/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Humanos
13.
Elife ; 82019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478835

RESUMO

Hepatitis C virus (HCV) is a highly variable pathogen that frequently establishes chronic infection. This genetic variability is affected by the adaptive immune response but the contribution of other host factors is unclear. Here, we examined the role played by interferon lambda-4 (IFN-λ4) on HCV diversity; IFN-λ4 plays a crucial role in spontaneous clearance or establishment of chronicity following acute infection. We performed viral genome-wide association studies using human and viral data from 485 patients of white ancestry infected with HCV genotype 3a. We demonstrate that combinations of host genetic variants, which determine IFN-λ4 protein production and activity, influence amino acid variation across the viral polyprotein - not restricted to specific viral proteins or HLA restricted epitopes - and modulate viral load. We also observed an association with viral di-nucleotide proportions. These results support a direct role for IFN-λ4 in exerting selective pressure across the viral genome, possibly by a novel mechanism.


Assuntos
Antivirais/metabolismo , Variação Genética , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/virologia , Fatores Imunológicos/metabolismo , Interleucinas/metabolismo , Grupo com Ancestrais do Continente Europeu , Estudo de Associação Genômica Ampla , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C/imunologia , Interações Hospedeiro-Patógeno , Humanos , Interleucinas/genética , Seleção Genética , Carga Viral
14.
Cell Biochem Biophys ; 77(4): 319-333, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31559538

RESUMO

Influenza virus is known for its intermittent outbreaks affecting billions of people worldwide. Several neuraminidase inhibitors have been used in practice to overcome this situation. However, advent of new resistant mutants has limited its clinical utilization. In the recent years drug repurposing technique has attained the limelight as it is cost effective and reduces the time consumed for drug discovery. Here, we present multi-dimensional repurposing strategy that integrates the results of ligand-, energy-, receptor cavity, and shape-based pharmacophore algorithm to effectively identify novel drug candidate for influenza. The pharmacophore hypotheses were generated by utilizing the PHASE module of Schrödinger. The generated hypotheses such as AADP, AADDD, and DDRRNH, respectively, for ligand-, e-pharmacophore and receptor cavity based approach alongside shape of oseltamivir were successfully utilized to screen the DrugBank database. Subsequently, these models were evaluated for their differentiating ability using Enrichment calculation. Receiver operating curve and enrichment factors from the analysis indicate that the models possess better capability to screen actives from decoy set of molecules. Eventually, the hits retrieved from different hypotheses were subjected to molecular docking using Glide module of Schrödinger Suite. The results of different algorithms were then combined to eliminate false positive hits and to demonstrate reliable prediction performance than existing approaches. Of note, Pearson's correlation coefficients were calculated to examine the extent of correlation between the glide score and IC50 values. Further, the interaction profile, pharmacokinetic, and pharmacodynamics properties were analyzed for the hit compounds. The results from our analysis showed that alprostadil (DB00770) exhibits better binding affinity toward NA protein than the existing drug molecules. The biological activity of the hit was also predicted using PASS algorithm that renders the antiviral activity of the compound. Further, the results were validated using mutation analysis and molecular dynamic simulation studies. Indeed, this integrative filtering is able to exceed accuracy of other state-of-the-art methods for the drug discovery.


Assuntos
Descoberta de Drogas , Reposicionamento de Medicamentos , Algoritmos , Alprostadil/química , Alprostadil/metabolismo , Alprostadil/uso terapêutico , Antivirais/química , Antivirais/metabolismo , Antivirais/uso terapêutico , Sítios de Ligação , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neuraminidase/química , Neuraminidase/genética , Neuraminidase/metabolismo , Oseltamivir/química , Oseltamivir/metabolismo , Ligação Proteica
15.
Infez Med ; 27(3): 239-250, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31545767

RESUMO

After a long period of interferon-and ribavirin-based therapy (IFN/RBV), a very fast evolution in the development of directly acting antivirals (DAAs) has now established a totally new paradigm for the treatment chronic HCV infection. An efficacy rate within the 95-100% interval, safer and more tolerable drugs, much shorter treatment duration and a quicker establishment of the sustained virological response (SVR) are among the most relevant properties of new DAAs as compared to former IFN/RBV therapies. The last wave of DAAs is also characterized by a lesser tendency to generate or being victim of drug-drug interactions. Nevertheless, since the circumstances in which patients are also recipients of other medications are rather frequent, individualization of treatment is advised in order to minimize the risk of drug-drug interactions of clinical relevance. Three two-drug regimens are available in Italy for the treatment of chronic HCV infection: sofosbuvir/velpatasvir (SOF/VEL), glecaprevir/pibrentasvir (GLE/PIB) and grazoprevir/elbasvir (GZP/RLB). Based on the officially released summary of product characteristics (SmPC) of these three co-formulated dual regimens, we performed a comparative analysis concerning the drug-drug interactions possibly affecting the DAA regimens. According to specific individual conditions, including co-morbidities, the choice of the most appropriate regimen must carefully take into account, among the different variables, the metabolic profile of both DAAs and concurrent medications. The differences among the three regimens offer the possibility to avoid the occurrence of clinically relevant drug-drug interactions in most circumstance.


Assuntos
Antivirais/farmacologia , Benzimidazóis/farmacologia , Benzofuranos/farmacologia , Carbamatos/farmacologia , Hepatite C Crônica/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Imidazóis/farmacologia , Pirrolidinas/farmacologia , Quinoxalinas/farmacologia , Sofosbuvir/farmacologia , Sulfonamidas/farmacologia , Antivirais/metabolismo , Antivirais/uso terapêutico , Benzimidazóis/metabolismo , Benzofuranos/metabolismo , Carbamatos/metabolismo , Combinação de Medicamentos , Interações Medicamentosas , Hepatite C Crônica/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/metabolismo , Humanos , Imidazóis/metabolismo , Interferon-alfa/uso terapêutico , Itália , Polimedicação , Pirrolidinas/metabolismo , Quinoxalinas/metabolismo , Sofosbuvir/metabolismo , Sulfonamidas/metabolismo
16.
Appl Microbiol Biotechnol ; 103(20): 8473-8483, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31468087

RESUMO

Type III interferon (IFN-λ) has recently been shown to exert a significant antiviral impact against viruses in vertebrates. Avian leukosis virus subgroup J (ALV-J), which causes tumor disease and immunosuppression in infected chicken, is a retrovirus that is difficult to prevent and control because of a lack of vaccines and drugs. Here, we obtained chicken IFN-λ (chIFN-λ) using a silkworm bioreactor and demonstrated that chIFN-λ has antiviral activity against ALV-J infection of both chicken embryo fibroblast cell line (DF1) and epithelial cell line (LMH). We found that chIFN-λ triggered higher levels of particular type III interferon-stimulated genes (type III ISGs) including myxovirus resistance protein (Mx), viperin (RSAD2), and interferon-inducible transmembrane protein 3 (IFITM3) in DF1 and LMH cells. Furthermore, over-expression of Mx, viperin, and IFITM3 could inhibit ALV-J infection in DF1 and LMH cells. Therefore, these results suggested that the anti-ALV-J function of chIFN-λ was specifically implemented by induction of expression of type III ISGs. Our data identified chIFN-λ as a critical antiviral agent of ALV-J infection and provides a potentially and attractive platform for the production of commercial chIFN-λ.


Assuntos
Antivirais/metabolismo , Vírus da Leucose Aviária/crescimento & desenvolvimento , Galinhas , Interferons/metabolismo , Proteínas Recombinantes/metabolismo , Animais , Reatores Biológicos , Bombyx , Células Epiteliais/virologia , Fibroblastos/virologia , Expressão Gênica , Interferons/genética , Proteínas Recombinantes/genética
17.
Amino Acids ; 51(9): 1353-1363, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31446487

RESUMO

Interferons are signaling proteins that belong to the large class of cytokines and human interferons which are classified based on the type of receptor interactions: type I, II and III. IFNα2b belongs to the type I interferon class with a major therapeutic application for the treatment of hepatitis B and C infections. A recombinant form of IFNα2b expressed in E. coli, known as IntronA, has been approved by US Food and Drug Administration (FDA). IFN γ, also known as type II interferon, plays a significant role in the inhibition of viral replication. Actimmune® is a US Food and Drug Administration (FDA) approved version of IFN γ for the indication of reducing infections associated with chronic granulomatous disease and severe malignant osteopetrosis. In this study we have applied advanced analytical methods for the characterization of IFNα2b and IFN γ produced from Pichia pastoris. The multi-enzyme digestion approach has been developed to allow measurement of 100% sequence coverage and detailed analysis of post-translational variants and degradation products. In this manner, we identified the following variants in IFN α2b: N-terminal residual leader sequence, an amino acid substitution, oxidation of methionine residues and two sites of high mannose N-glycosylation. In the Pichia IFN γ produced material, our approach detected variants resulting from glycosylation, C-terminal proteolysis, oxidation of methionine residues and deamidation. In this manner, the analytical program was able to support rapid process development as well as identify product variants and degradation products in the resulting product.


Assuntos
Antivirais/química , Interferon-alfa/química , Interferon gama/química , Pichia/metabolismo , Sequência de Aminoácidos , Antivirais/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Desaminação , Glicosilação , Interferon-alfa/metabolismo , Interferon gama/metabolismo , Espectrometria de Massas/métodos , Oxirredução , Sinais Direcionadores de Proteínas , Proteólise , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
18.
J Microbiol Biotechnol ; 29(7): 1155-1164, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31280524

RESUMO

Lichens contain diverse bioactive secondary metabolites with various chemical and biological properties, which have been widely studied. However, details of the inhibitory mechanisms of their secondary metabolites against influenza A virus (IAV) have not been documented. Here, we investigated the antiviral effect of lichen extracts, obtained from South Korea, against IAV in MDCK cells. Of the lichens tested, Nipponoparmelia laevior (LC24) exhibited the most potent inhibitory effect against IAV infection. LC24 extract significantly increased cell viability, and reduced apoptosis in IAV-infected cells. The LC24 extract also markedly reduced (~ 3.2 logfold) IAV mRNA expression after 48 h of infection. To understand the antiviral mechanism of LC24 against IAV, proteomic (UPLC-HDMSE) analysis was performed to compare proteome modulation in IAV-infected (V) vs. mock (M) and LC24+IAV (LCV) vs. V cells. Based on Ingenuity Pathway Analysis (IPA), LC24 inhibited IAV infection by modulating several antiviral-related genes and proteins (HSPA4, HSPA5, HSPA8, ANXA1, ANXA2, HIF-1α, AKT1, MX1, HNRNPH1, HNRNPDL, PDIA3, and VCP) via different signaling pathways, including HIF-1α signaling, unfolded protein response, and interferon signaling. These molecules were identified as the specific biomarkers for controlling IAV in vitro and further confirmation of their potential against IAV in vivo is required. Our findings provide a platform for further studies on the application of lichen extracts against IAV.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Líquens/química , Infecções por Orthomyxoviridae/metabolismo , Animais , Antivirais/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cães , Líquens/metabolismo , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/virologia , Proteômica , RNA Mensageiro/metabolismo , República da Coreia , Transdução de Sinais/efeitos dos fármacos , Proteínas Virais/genética
19.
J Agric Food Chem ; 67(31): 8468-8475, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31310114

RESUMO

Fermentation of the fungal strain Skeletocutis sp. originating from Mount Elgon Natural Reserve in Kenya, followed by bioassay guided fractionation led to the isolation of 12 previously undescribed metabolites named skeletocutins A-L (1-5 and 7-13) together with the known tyromycin A (6). Their structures were assigned by NMR spectroscopy complemented by HR-ESIMS. Compounds 1-6 and 11-13 exhibited selective activities against Gram-positive bacteria, while compound 10 weakly inhibited the formation of biofilm of Staphylococcus aureus. The isolated metabolites were also evaluated for inhibition of L-leucine aminopeptidase, since tyromycin A had previously been reported to possess such activities but only showed weak effects. Furthermore, all compounds were tested for antiviral activity against Hepatitis C virus (HCV), and compound 6 moderately inhibited HCV infectivity with an IC50 of 6.6 µM.


Assuntos
Antibacterianos/farmacologia , Polyporales/química , Madeira/microbiologia , Antibacterianos/química , Antibacterianos/metabolismo , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Quênia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Polyporales/crescimento & desenvolvimento , Polyporales/isolamento & purificação , Polyporales/metabolismo
20.
Biomed Chromatogr ; 33(11): e4644, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31276615

RESUMO

Telaprevir is a potent, selective, peptidomimetic inhibitor of the hepatitis C virus (HCV) NS3-4A serine protease. it is used for the treatment of HCV infection in combination with peginterferon alfa and ribavirin. In the present work, the E-Z isomerization process of telaprevir in solution was revealed by online HPLC-DAD (diode array detector)-MS, variable-temperature and variable-gradient experiments. The molecular geometry information of the two isomers was established by molecular mechanics calculations, and good correlation between the two isomers' UV-vis spectra and their molecular geometry information was also discovered. In addition, it was revealed by molecular docking that the two isomers have different affinities to HCV NS3•4A protease, and the Z isomer, the minor form of telaprevir in solution, is the more effective inhibitor of HCV NS3•4A protease. The investigation can provide more structure information about telaprevir in solution and in the binding process of HCV NS3•4A protease.


Assuntos
Antivirais/química , Antivirais/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Isomerismo , Espectrometria de Massas , Simulação de Acoplamento Molecular , Serina Proteases/química , Serina Proteases/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
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