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1.
Nat Commun ; 11(1): 4931, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004795

RESUMO

Testis-restricted melanoma antigen (MAGE) proteins are frequently hijacked in cancer and play a critical role in tumorigenesis. MAGEs assemble with E3 ubiquitin ligases and function as substrate adaptors that direct the ubiquitination of novel targets, including key tumor suppressors. However, how MAGEs recognize their targets is unknown and has impeded the development of MAGE-directed therapeutics. Here, we report the structural basis for substrate recognition by MAGE ubiquitin ligases. Biochemical analysis of the degron motif recognized by MAGE-A11 and the crystal structure of MAGE-A11 bound to the PCF11 substrate uncovered a conserved substrate binding cleft (SBC) in MAGEs. Mutation of the SBC disrupted substrate recognition by MAGEs and blocked MAGE-A11 oncogenic activity. A chemical screen for inhibitors of MAGE-A11:substrate interaction identified 4-Aminoquinolines as potent inhibitors of MAGE-A11 that show selective cytotoxicity. These findings provide important insights into the large family of MAGE ubiquitin ligases and identify approaches for developing cancer-specific therapeutics.


Assuntos
Antígenos de Neoplasias/ultraestrutura , Proteínas de Neoplasias/ultraestrutura , Neoplasias/tratamento farmacológico , Ubiquitina-Proteína Ligases/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Motivos de Aminoácidos , Aminoquinolinas/farmacologia , Aminoquinolinas/uso terapêutico , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Células HeLa , Ensaios de Triagem em Larga Escala , Humanos , Mutagênese , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patologia , Estudo de Prova de Conceito , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Domínios Proteicos/genética , Mapeamento de Interação de Proteínas , Relação Estrutura-Atividade , Especificidade por Substrato/efeitos dos fármacos , Especificidade por Substrato/genética , Ubiquitinação/efeitos dos fármacos , Ubiquitinação/genética
2.
Toxins (Basel) ; 12(9)2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32957454

RESUMO

The deadly pandemic named COVID-19, caused by a new coronavirus (SARS-CoV-2), emerged in 2019 and is still spreading globally at a dangerous pace. As of today, there are no proven vaccines, therapies, or even strategies to fight off this virus. Here, we describe the in silico docking results of a novel broad range anti-infective fusion protein RTAM-PAP1 against the various key proteins of SARS-CoV-2 using the latest protein-ligand docking software. RTAM-PAP1 was compared against the SARS-CoV-2 B38 antibody, ricin A chain, a pokeweed antiviral protein from leaves, and the lectin griffithsin using the special CoDockPP COVID-19 version. These experiments revealed novel binding mechanisms of RTAM-PAP1 with a high affinity to numerous SARS-CoV-2 key proteins. RTAM-PAP1 was further characterized in a preliminary toxicity study in mice and was found to be a potential therapeutic candidate. These findings might lead to the discovery of novel SARS-CoV-2 targets and therapeutic protein structures with outstanding functions.


Assuntos
Antivirais/química , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Ligação Proteica/efeitos dos fármacos , Proteínas Inativadoras de Ribossomos Tipo 1/química , Proteínas Inativadoras de Ribossomos Tipo 1/uso terapêutico , Ricina/uso terapêutico , Animais , Simulação por Computador , Humanos , Camundongos , Modelos Animais , Pandemias , Phytolacca americana/química , Folhas de Planta/química , Proteínas Inativadoras de Ribossomos Tipo 1/genética
3.
Nat Commun ; 11(1): 4578, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929090

RESUMO

Thalidomide and its derivatives exert not only therapeutic effects as immunomodulatory drugs (IMiDs) but also adverse effects such as teratogenicity, which are due in part to different C2H2 zinc-finger (ZF) transcription factors, IKZF1 (or IKZF3) and SALL4, respectively. Here, we report the structural bases for the SALL4-specific proteasomal degradation induced by 5-hydroxythalidomide, a primary thalidomide metabolite generated by the enzymatic activity of cytochrome P450 isozymes, through the interaction with cereblon (CRBN). The crystal structure of the metabolite-mediated human SALL4-CRBN complex and mutagenesis studies elucidate the complex formation enhanced by the interaction between CRBN and an additional hydroxy group of (S)-5-hydroxythalidomide and the variation in the second residue of ß-hairpin structure that underlies the C2H2 ZF-type neo-morphic substrate (neosubstrate) selectivity of 5-hydroxythalidomide. These findings deepen our understanding of the pharmaceutical action of IMiDs and provide structural evidence that the glue-type E3 ligase modulators cause altered neosubstrate specificities through their metabolism.


Assuntos
Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Talidomida/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Células HEK293 , Humanos , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Estereoisomerismo , Homologia Estrutural de Proteína , Especificidade por Substrato , Talidomida/química , Talidomida/farmacologia , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
4.
Int J Antimicrob Agents ; 56(2): 106020, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32862840

RESUMO

The emergence of SARS-coronavirus-2 (SARS-CoV-2) has led to a global pandemic disease referred to as coronavirus disease 19 (COVID-19). Hydroxychloroquine (CLQ-OH)/azithromycin (ATM) combination therapy is currently being tested for the treatment of COVID-19, with promising results. However, the molecular mechanism of action of this combination is not yet established. Using molecular dynamics (MD) simulations, this study shows that the drugs act in synergy to prevent any close contact between the virus and the plasma membrane of host cells. Unexpected molecular similarity is shown between ATM and the sugar moiety of GM1, a lipid raft ganglioside acting as a host attachment cofactor for respiratory viruses. Due to this mimicry, ATM interacts with the ganglioside-binding domain of SARS-CoV-2 spike protein. This binding site shared by ATM and GM1 displays a conserved amino acid triad Q-134/F-135/N-137 located at the tip of the spike protein. CLQ-OH molecules are shown to saturate virus attachment sites on gangliosides in the vicinity of the primary coronavirus receptor, angiotensin-converting enzyme-2 (ACE-2). Taken together, these data show that ATM is directed against the virus, whereas CLQ-OH is directed against cellular attachment cofactors. We conclude that both drugs act as competitive inhibitors of SARS-CoV-2 attachment to the host-cell membrane. This is consistent with a synergistic antiviral mechanism at the plasma membrane level, where therapeutic intervention is likely to be most efficient. This molecular mechanism may explain the beneficial effects of CLQ-OH/ATM combination therapy in patients with COVID-19. Incidentally, the data also indicate that the conserved Q-134/F-135/N-137 triad could be considered as a target for vaccine strategies.


Assuntos
Azitromicina/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Gangliosídeo G(M1)/metabolismo , Hidroxicloroquina/farmacologia , Pneumonia Viral/tratamento farmacológico , Glicoproteína da Espícula de Coronavírus/metabolismo , Ligação Viral/efeitos dos fármacos , Sequência de Aminoácidos , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Sítios de Ligação/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Simulação de Dinâmica Molecular , Pandemias , Peptidil Dipeptidase A/metabolismo , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos/efeitos dos fármacos , Alinhamento de Sequência
5.
Nat Commun ; 11(1): 3954, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770072

RESUMO

The systematic stabilization of protein-protein interactions (PPI) has great potential as innovative drug discovery strategy to target novel and hard-to-drug protein classes. The current lack of chemical starting points and focused screening opportunities limits the identification of small molecule stabilizers that engage two proteins simultaneously. Starting from our previously described virtual screening strategy to identify inhibitors of 14-3-3 proteins, we report a conceptual molecular docking approach providing concrete entries for discovery and rational optimization of stabilizers for the interaction of 14-3-3 with the carbohydrate-response element-binding protein (ChREBP). X-ray crystallography reveals a distinct difference in the binding modes between weak and general inhibitors of 14-3-3 complexes and a specific, potent stabilizer of the 14-3-3/ChREBP complex. Structure-guided stabilizer optimization results in selective, up to 26-fold enhancement of the 14-3-3/ChREBP interaction. This study demonstrates the potential of rational design approaches for the development of selective PPI stabilizers starting from weak, promiscuous PPI inhibitors.


Assuntos
Proteínas 14-3-3/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Desenho de Fármacos , Descoberta de Drogas , Proteínas 14-3-3/antagonistas & inibidores , Proteínas 14-3-3/ultraestrutura , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/ultraestrutura , Cristalografia por Raios X , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade
6.
Nat Commun ; 11(1): 3848, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737286

RESUMO

Amyotrophic Lateral Sclerosis (ALS) is a fatal disease characterized by the degeneration of upper and lower motor neurons (MNs). We find a significant reduction of the retromer complex subunit VPS35 in iPSCs-derived MNs from ALS patients, in MNs from ALS post mortem explants and in MNs from SOD1G93A mice. Being the retromer involved in trafficking of hydrolases, a pathological hallmark in ALS, we design, synthesize and characterize an array of retromer stabilizers based on bis-guanylhydrazones connected by a 1,3-phenyl ring linker. We select compound 2a as a potent and bioavailable interactor of VPS35-VPS29. Indeed, while increasing retromer stability in ALS mice, compound 2a attenuates locomotion impairment and increases MNs survival. Moreover, compound 2a increases VPS35 in iPSCs-derived MNs and shows brain bioavailability. Our results clearly suggest the retromer as a valuable druggable target in ALS.


Assuntos
Esclerose Amiotrófica Lateral/tratamento farmacológico , Hidrazonas/farmacologia , Neurônios Motores/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas de Transporte Vesicular/genética , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Esclerose Amiotrófica Lateral/patologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Diferenciação Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Hidrazonas/síntese química , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Ligação Proteica/efeitos dos fármacos , Multimerização Proteica , Relação Estrutura-Atividade , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Proteínas de Transporte Vesicular/metabolismo
7.
PLoS One ; 15(8): e0236754, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756590

RESUMO

The antimalarial agent mefloquine is currently being investigated for its potential to inhibit feline coronavirus and feline calicivirus infections. A simple, high pressure liquid chromatography assay was developed to detect mefloquine plasma concentrations in feline plasma. The assay's lower limit of quantification was 250 ng/mL. The mean ± standard deviation intra- and inter-day precision expressed as coefficients of variation were 6.83 ± 1.75 and 5.33 ± 1.37%, respectively, whereas intra- and inter-day accuracy expressed as a percentage of the bias were 11.40 ± 3.73 and 10.59 ± 3.88%, respectively. Accordingly, this validated assay should prove valuable for future in vivo clinical trials of mefloquine as an antiviral agent against feline coronavirus and feline calicivirus. However, the proportion of mefloquine binding to feline plasma proteins has not been reported. The proportion of drug bound to plasma protein binding is an important concept when developing drug dosing regimens. As cats with feline infectious peritonitis (FIP) demonstrate altered concentrations of plasma proteins, the proportion of mefloquine binding to plasma proteins in both clinically normal cats and FIP-affected cats was also investigated. An in vitro method using rapid equilibrium dialysis demonstrated that mefloquine was highly plasma protein bound in both populations (on average > 99%).


Assuntos
Calicivirus Felino/efeitos dos fármacos , Coronavirus Felino/efeitos dos fármacos , Peritonite Infecciosa Felina/tratamento farmacológico , Mefloquina/farmacologia , Animais , Proteínas Sanguíneas/genética , Infecções por Caliciviridae/tratamento farmacológico , Infecções por Caliciviridae/veterinária , Infecções por Caliciviridae/virologia , Calicivirus Felino/patogenicidade , Gatos , Coronavirus Felino/patogenicidade , Peritonite Infecciosa Felina/sangue , Peritonite Infecciosa Felina/virologia , Ligação Proteica/efeitos dos fármacos
8.
Eur J Pharmacol ; 884: 173455, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32745604

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a beta coronavirus that uses the human angiotensin-converting enzyme 2 (ACE2) receptor as a point of entry. The present review discusses the origin and structure of the virus and its mechanism of cell entry followed by the therapeutic potentials of strategies directed towards SARS-CoV2-ACE2 binding, the renin-angiotensin system, and the kinin-kallikrein system. SARS-CoV2-ACE2 binding-directed approaches mainly consist of targeting receptor binding domain, ACE2 blockers, soluble ACE2, and host protease inhibitors. In conclusion, blocking or manipulating the SARS-CoV2-ACE2 binding interface perhaps offers the best tactic against the virus that should be treated as a fundamental subject of future research.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus , Descoberta de Drogas/métodos , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Receptores Virais/metabolismo
9.
ACS Nano ; 14(8): 10616-10623, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32806067

RESUMO

The receptor-binding domain (RBD) of the SARS-CoV-2 spike protein plays a crucial role in binding the human cell receptor ACE2 that is required for viral entry. Many studies have been conducted to target the structures of RBD-ACE2 binding and to design RBD-targeting vaccines and drugs. Nevertheless, mutations distal from the SARS-CoV-2 RBD also impact its transmissibility and antibody can target non-RBD regions, suggesting the incomplete role of the RBD region in the spike protein-ACE2 binding. Here, in order to elucidate distant binding mechanisms, we analyze complexes of ACE2 with the wild-type spike protein and with key mutants via large-scale all-atom explicit solvent molecular dynamics simulations. We find that though distributed approximately 10 nm away from the RBD, the SARS-CoV-2 polybasic cleavage sites enhance, via electrostatic interactions and hydration, the RBD-ACE2 binding affinity. A negatively charged tetrapeptide (GluGluLeuGlu) is then designed to neutralize the positively charged arginine on the polybasic cleavage sites. We find that the tetrapeptide GluGluLeuGlu binds to one of the three polybasic cleavage sites of the SARS-CoV-2 spike protein lessening by 34% the RBD-ACE2 binding strength. This significant binding energy reduction demonstrates the feasibility to neutralize RBD-ACE2 binding by targeting this specific polybasic cleavage site. Our work enhances understanding of the binding mechanism of SARS-CoV-2 to ACE2, which may aid the design of therapeutics for COVID-19 infection.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Substituição de Aminoácidos , Antivirais/química , Antivirais/farmacologia , Betacoronavirus/química , Betacoronavirus/genética , Sítios de Ligação/genética , Desenho de Fármacos , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Humanos , Simulação de Dinâmica Molecular , Mutação , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Ligação Proteica/fisiologia , Domínios Proteicos , Receptores Virais/química , Receptores Virais/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Internalização do Vírus
10.
Sci Rep ; 10(1): 13866, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807895

RESUMO

The Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). The virus has rapidly spread in humans, causing the ongoing Coronavirus pandemic. Recent studies have shown that, similarly to SARS-CoV, SARS-CoV-2 utilises the Spike glycoprotein on the envelope to recognise and bind the human receptor ACE2. This event initiates the fusion of viral and host cell membranes and then the viral entry into the host cell. Despite several ongoing clinical studies, there are currently no approved vaccines or drugs that specifically target SARS-CoV-2. Until an effective vaccine is available, repurposing FDA approved drugs could significantly shorten the time and reduce the cost compared to de novo drug discovery. In this study we attempted to overcome the limitation of in silico virtual screening by applying a robust in silico drug repurposing strategy. We combined and integrated docking simulations, with molecular dynamics (MD), Supervised MD (SuMD) and Steered MD (SMD) simulations to identify a Spike protein - ACE2 interaction inhibitor. Our data showed that Simeprevir and Lumacaftor bind the receptor-binding domain of the Spike protein with high affinity and prevent ACE2 interaction.


Assuntos
Betacoronavirus/efeitos dos fármacos , Biologia Computacional/métodos , Infecções por Coronavirus/metabolismo , Descoberta de Drogas/métodos , Reposicionamento de Medicamentos/métodos , Pneumonia Viral/metabolismo , Aminopiridinas/farmacologia , Benzodioxóis/farmacologia , Betacoronavirus/química , Sítios de Ligação , Infecções por Coronavirus/virologia , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Conformação Proteica , Domínios Proteicos/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Simeprevir/farmacologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo
11.
Protein Cell ; 11(10): 723-739, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32754890

RESUMO

Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide, such as the on-going outbreak of the novel coronavirus SARS-CoV-2. Herein, we identified two potent inhibitors of human DHODH, S312 and S416, with favorable drug-likeness and pharmacokinetic profiles, which all showed broad-spectrum antiviral effects against various RNA viruses, including influenza A virus, Zika virus, Ebola virus, and particularly against SARS-CoV-2. Notably, S416 is reported to be the most potent inhibitor so far with an EC50 of 17 nmol/L and an SI value of 10,505.88 in infected cells. Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells. This work demonstrates that both S312/S416 and old drugs (Leflunomide/Teriflunomide) with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide, no matter such viruses are mutated or not.


Assuntos
Antivirais/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Oxirredutases/antagonistas & inibidores , Pandemias , Pneumonia Viral/tratamento farmacológico , Vírus de RNA/efeitos dos fármacos , Animais , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/fisiologia , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular , Infecções por Coronavirus/virologia , Crotonatos/farmacologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Técnicas de Inativação de Genes , Humanos , Vírus da Influenza A/efeitos dos fármacos , Leflunomida/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/tratamento farmacológico , Oseltamivir/uso terapêutico , Oxirredutases/metabolismo , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Pirimidinas/biossíntese , Vírus de RNA/fisiologia , Relação Estrutura-Atividade , Toluidinas/farmacologia , Ubiquinona/metabolismo , Replicação Viral/efeitos dos fármacos
12.
Life Sci ; 258: 118228, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781071

RESUMO

AIMS: Cyclin-dependent kinase 9 (CDK9) is a member of the CDK subfamily and plays a major role in the regulation of transcriptional elongation. It has attracted widespread attention as a therapeutic target for cancer. Here, we aimed to explore novel CDK 9 inhibitors by using a hybrid virtual screening strategy. MAIN METHODS: A hybrid virtual screening strategy was constructed with computer-aided drug design (CADD). First, compounds were filtered in accordance with Lipinski's rule of five and adsorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. Second, a 3D-QSAR pharmacophore model was built and used as a 3D query to screen the obtained hit compounds. Third, the hit compounds were subjected to molecular docking studies. Fourth, molecular dynamics (MD) simulations were performed on CDK9 in complex with the final hits to examine the structural stability. Finally, CDK9 kinase biochemical assay was performed to identify the biological activity of the hit compounds. KEY FINDINGS: Seven hit compounds were screened out. These hit compounds showed drug-like properties in accordance with Lipinski's rule of five and ADMET. Complexes involving the six hit compounds bound to CDK9 exhibited good structural stability in the MD simulation. Furthermore, these six hit compounds had strong inhibitory activity against CDK9 kinase. In particular, hit 3 showed the most promising activity with the percentage of 71%. SIGNIFICANCE: The six hit compounds may be promising novel CDK9 inhibitors, and the hybrid virtual screening strategy designed in this study provides an important reference for the design and synthesis of novel CDK9 inhibitors.


Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/metabolismo , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/metabolismo , Quinase 9 Dependente de Ciclina/química , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Estrutura Secundária de Proteína
13.
PLoS One ; 15(8): e0237110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790695

RESUMO

Serine/threonine phosphatases are responsible for modulating the activities of the protein kinases implicated in the development of several pathologies. Here we identified by a PEP-scan approach a peptide of LRRK2, a Parkinson's disease associated protein, interacting with the phosphatase PP1. In order to study its biological activity, the peptide was fused via its N-terminal to an optimized cell penetrating peptide. We synthesized from the original peptide five interfering peptides and identified two (Mut3DPT-LRRK2-Short and Mut3DPT-LRRK2-Long) able to disrupt the LRRK2/PP1 interaction by competition in anti-LRRK2 immunoprecipitates. Using FITC-labelled peptides, we confirmed their internalization into cell lines as well as into primary cells obtained from healthy or ill human donors. We confirmed by ELISA test the association of Mut3DPT-LRRK2-Long peptide to purified PP1 protein. The peptides Mut3DPT-LRRK2-5 to 8 with either N or C-terminal deletions were not able to disrupt the association LRRK2/PP1 nor to associate with purified PP1 protein. The interfering sequences blocking the PP1/LRRK2 interaction were also fused to a shuttle peptide able to cross the blood brain barrier and showed that the newly generated peptides BBB-LRRK2-Short and BBB-LRRK2-Long were highly resistant to protease degradation. Furthermore, they blocked PP1/LRRK2 interaction and they penetrated into cells. Hence, these newly generated peptides can be employed as new tools in the investigation of the role of the LRRK2/PP1 interaction in normal and pathological conditions.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Oligopeptídeos/química , Proteína Fosfatase 1/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Oligopeptídeos/síntese química , Oligopeptídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Proteólise
14.
Life Sci ; 257: 118080, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653520

RESUMO

The COVID-19 pandemic raised by SARS-CoV-2 is a public health emergency. However, lack of antiviral drugs and vaccine against human coronaviruses demands a concerted approach to challenge the SARS-CoV-2 infection. Under limited resource and urgency, combinatorial computational approaches to identify the potential inhibitor from known drugs could be applied against risen COVID-19 pandemic. Thereof, this study attempted to purpose the potent inhibitors from the approved drug pool against SARS-CoV-2 main protease (Mpro). To circumvent the issue of lead compound from available drugs as antivirals, antibiotics with broad spectrum of viral activity, i.e. doxycycline, tetracycline, demeclocycline, and minocycline were chosen for molecular simulation analysis against native ligand N3 inhibitor in SARS-CoV-2 Mpro crystal structure. Molecular docking simulation predicted the docking score >-7 kcal/mol with significant intermolecular interaction at the catalytic dyad (His41 and Cys145) and other essential substrate binding residues of SARS-CoV-2 Mpro. The best ligand conformations were further studied for complex stability and intermolecular interaction profiling with respect to time under 100 ns classical molecular dynamics simulation, established the significant stability and interactions of selected antibiotics by comparison to N3 inhibitor. Based on combinatorial molecular simulation analysis, doxycycline and minocycline were selected as potent inhibitor against SARS-CoV-2 Mpro which can used in combinational therapy against SARS-CoV-2 infection.


Assuntos
Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Tetraciclinas/farmacologia , Antibacterianos , Antivirais/farmacologia , Sítios de Ligação/fisiologia , Biologia Computacional/métodos , Infecções por Coronavirus/tratamento farmacológico , Bases de Dados Genéticas , Humanos , Ligantes , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Pandemias , Peptídeo Hidrolases/efeitos dos fármacos , Peptídeo Hidrolases/farmacologia , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases , Ligação Proteica/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores
15.
Artigo em Inglês | MEDLINE | ID: mdl-32687406

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV), an enveloped virus with a positive-sense single-stranded RNA genome, facilitates the host cell entry through intricate interactions with proteins and lipids of the cell membrane. The detailed molecular mechanism involves binding to the host cell receptor and fusion at the plasma membrane or after being trafficked to late endosomes under favorable environmental conditions. A crucial event in the process is the proteolytic cleavage of the viral spike protein by the host's endogenous proteases that releases the fusion peptide enabling fusion with the host cellular membrane system. The present review details the mechanism of viral fusion with the host and highlights the therapeutic options that prevent SARS-CoV-2 entry in humans.


Assuntos
Betacoronavirus/metabolismo , Membrana Celular/metabolismo , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/metabolismo , Pneumonia Viral/prevenção & controle , Proteínas Virais de Fusão/metabolismo , Sequência de Aminoácidos , Animais , Betacoronavirus/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/virologia , Humanos , Peptidil Dipeptidase A/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas Virais de Fusão/efeitos dos fármacos
16.
Int J Mol Sci ; 21(14)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708196

RESUMO

(1) Background: Virtual screening studies on the therapeutically relevant proteins of the severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) require a detailed characterization of their druggable binding sites, and, more generally, a convenient pocket mapping represents a key step for structure-based in silico studies; (2) Methods: Along with a careful literature search on SARS-CoV-2 protein targets, the study presents a novel strategy for pocket mapping based on the combination of pocket (as performed by the well-known FPocket tool) and docking searches (as performed by PLANTS or AutoDock/Vina engines); such an approach is implemented by the Pockets 2.0 plug-in for the VEGA ZZ suite of programs; (3) Results: The literature analysis allowed the identification of 16 promising binding cavities within the SARS-CoV-2 proteins and the here proposed approach was able to recognize them showing performances clearly better than those reached by the sole pocket detection; and (4) Conclusions: Even though the presented strategy should require more extended validations, this proved successful in precisely characterizing a set of SARS-CoV-2 druggable binding pockets including both orthosteric and allosteric sites, which are clearly amenable for virtual screening campaigns and drug repurposing studies. All results generated by the study and the Pockets 2.0 plug-in are available for download.


Assuntos
Antivirais/química , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Proteínas Virais/química , Sítios de Ligação/efeitos dos fármacos , Reposicionamento de Medicamentos , Humanos , Simulação de Acoplamento Molecular , Pandemias , Ligação Proteica/efeitos dos fármacos , Conformação Proteica
17.
PLoS Biol ; 18(6): e3000732, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603375

RESUMO

Coordination of gene expression with nutrient availability supports proliferation and homeostasis and is shaped by protein acetylation. Yet how physiological/pathological signals link acetylation to specific gene expression programs and whether such responses are cell-type-specific is unclear. AMP-activated protein kinase (AMPK) is a key energy sensor, activated by glucose limitation to resolve nutrient supply-demand imbalances, critical for diabetes and cancer. Unexpectedly, we show here that, in gastrointestinal cancer cells, glucose activates AMPK to selectively induce EP300, but not CREB-binding protein (CBP). Consequently, EP300 is redirected away from nuclear receptors that promote differentiation towards ß-catenin, a driver of proliferation and colorectal tumorigenesis. Importantly, blocking glycogen synthesis permits reactive oxygen species (ROS) accumulation and AMPK activation in response to glucose in previously nonresponsive cells. Notably, glycogen content and activity of the ROS/AMPK/EP300/ß-catenin axis are opposite in healthy versus tumor sections. Glycogen content reduction from healthy to tumor tissue may explain AMPK switching from tumor suppressor to activator during tumor evolution.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias Colorretais/metabolismo , Proteína p300 Associada a E1A/metabolismo , Glucose/farmacologia , Animais , Proteína de Ligação a CREB/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Ativação Enzimática/efeitos dos fármacos , Glicogênio/metabolismo , Camundongos Endogâmicos C57BL , Ligação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismo
18.
Chem Biol Interact ; 328: 109188, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679048

RESUMO

We have reported that gestational exposure to hexavalent chromium (CrVI) represses androgen receptor (Ar) and follicle stimulating hormone receptor (Fshr) in Sertoli cells (SCs) of adult rats, while the mechanism underlying remains obscure. We tested the hypothesis "transient gestational exposure to CrVI during the critical embryonic windows of testicular differentiation and growth may have adverse impact on transcription factors controlling the expression of Ar and Fshr in SCs of the F1 progeny". CrVI (K2Cr2O7) was given through drinking water (50 ppm, 100 ppm and 200 ppm), to pregnant rats from gestational day 9-14 (testicular differentiation) and 15 to 21 (prenatal differentiation and proliferation of SC); male progenies were sacrificed on postnatal day 30 (Completion of postnatal SC maturation). A significant increase in free radicals and decrease in enzymatic and non-enzymatic antioxidants were observed in SCs of experimental rats. Real time PCR and western blot data showed decreased expression of Ar, Fshr, Inhibin B, Transferrin, Androgen binding protein, Claudin 11 and Occludin in SCs of experimental rats; concentrations of lactate, pyruvate and retinoic acid also decreased. Serum FSH, luteinizing hormone and estradiol increased, whereas testosterone and prolactin decreased in experimental rats. Western blot detection revealed decreased levels of transcription factors regulating Fshr viz., USF-1, USF-2, SF-1, c-fos, c-jun and GATA 1, and those of Ar viz., Sp-1, ARA54, SRC-1 and CBP in experimental rats, whereas the levels of cyclinD1 and p53, repressors of Ar increased. ChIP assay detected decreased USF-1 and USF-2 binding to Fshr promoter, and binding of Sp-1 to Ar promoter. We conclude that gestational exposure to CrVI affects SC structure and function in F1 progeny by inducing oxidative stress and diminishing the expression of Ar and Fshr through attenuation of their specific transcriptional regulators and their interaction with the respective promoter.


Assuntos
Cromo/toxicidade , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Receptores Androgênicos/metabolismo , Receptores do FSH/metabolismo , Células de Sertoli/metabolismo , Maturidade Sexual , Fatores de Transcrição/metabolismo , Animais , Antioxidantes/metabolismo , Disponibilidade Biológica , Feminino , Radicais Livres/metabolismo , Hormônios/sangue , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Ratos Wistar , Receptores Androgênicos/genética , Receptores do FSH/genética , Células de Sertoli/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Proteínas de Junções Íntimas/metabolismo
19.
PLoS One ; 15(7): e0236288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32702049

RESUMO

Although voltage-gated Ca2+ channels (VGCC) are a major Ca2+ entry pathway in vascular smooth muscle cells (VSMCs), several other Ca2+-influx mechanisms exist and play important roles in vasoreactivity. One of these is store-operated Ca2+ entry (SOCE), mediated by an interaction between STIM1 and Orai1. Although SOCE is an important mechanism of Ca2+ influx in non-excitable cells (cells that lack VGCC); there is debate regarding the contribution of SOCE to regulate VSMC contractility and the molecular components involved. Our previous data suggest acid-sensing ion channel 1a (ASIC1a) is a necessary component of SOCE and vasoconstriction in small pulmonary arteries. However, it is unclear if ASIC1a similarly contributes to SOCE and vascular reactivity in systemic arteries. Considering the established role of Orai1 in mediating SOCE in the systemic circulation, we hypothesize the involvement of ASIC1a in SOCE and resultant vasoconstriction is unique to the pulmonary circulation. To test this hypothesis, we examined the roles of Orai1 and ASIC1a in SOCE- and endothelin-1 (ET-1)-induced vasoconstriction in small pulmonary and mesenteric arteries. We found SOCE is coupled to vasoconstriction in pulmonary arteries but not mesenteric arteries. In pulmonary arteries, inhibition of ASIC1a but not Orai1 attenuated SOCE- and ET-1-induced vasoconstriction. However, neither inhibition of ASIC1a nor Orai1 altered ET-1-induced vasoconstriction in mesenteric arteries. We conclude that SOCE plays an important role in pulmonary, but not mesenteric, vascular reactivity. Furthermore, in contrast to the established role of Orai1 in SOCE in non-excitable cells, the SOCE response in pulmonary VSMCs is largely mediated by ASIC1a.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Cálcio/metabolismo , Artérias Mesentéricas/fisiologia , Artéria Pulmonar/fisiologia , Vasoconstrição , Canais Iônicos Sensíveis a Ácido/genética , Animais , Canais de Cálcio Tipo L/metabolismo , Endotelina-1/farmacologia , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Ligação Proteica/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Molécula 1 de Interação Estromal/metabolismo
20.
Biochem Pharmacol ; 178: 114123, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593613

RESUMO

Commonly used drugs for treating many conditions are either natural products or derivatives. In silico modelling has identified several natural products including quercetin as potential highly effective disruptors of the initial infection process involving binding to the interface between the SARS-CoV-2 (Covid-19) Viral Spike Protein and the epithelial cell Angiotensin Converting Enzyme-2 (ACE2) protein. Here we argue that the oral route of administration of quercetin is unlikely to be effective in clinical trials owing to biotransformation during digestion, absorption and metabolism, but suggest that agents could be administered directly by alternative routes such as a nasal or throat spray.


Assuntos
Betacoronavirus/efeitos dos fármacos , Produtos Biológicos/farmacologia , Peptidil Dipeptidase A/metabolismo , Quercetina/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Betacoronavirus/metabolismo , Betacoronavirus/fisiologia , Produtos Biológicos/administração & dosagem , Produtos Biológicos/química , Ensaios Clínicos como Assunto/métodos , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Estrutura Molecular , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Quercetina/administração & dosagem , Quercetina/química , Internalização do Vírus/efeitos dos fármacos
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