Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
J Chem Inf Model ; 64(13): 4991-5005, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38920403

RESUMO

The ability to conduct effective high throughput screening (HTS) campaigns in drug discovery is often hampered by the detection of false positives in these assays due to small colloidally aggregating molecules (SCAMs). SCAMs can produce artifactual hits in HTS by nonspecific inhibition of the protein target. In this work, we present a new computational prediction tool for detecting SCAMs based on their 2D chemical structure. The tool, called the boosted aggregation detection (BAD) molecule filter, employs decision tree ensemble methods, namely, the CatBoost classifier and the light gradient-boosting machine, to significantly improve the detection of SCAMs. In developing the filter, we explore models trained on individual data sets, a consensus approach using these models, and, third, a merged data set approach, each tailored for specific drug discovery needs. The individual data set method emerged as most effective, achieving 93% sensitivity and 90% specificity, outperforming existing state-of-the-art models by 20 and 5%, respectively. The consensus models offer broader chemical space coverage, exceeding 90% for all testing sets. This feature is an important aspect particularly for early stage medicinal chemistry projects, and provides information on applicability domain. Meanwhile, the merged data set models demonstrated robust performance, with a notable sensitivity of 79% in the comprehensive 10-fold cross-validation test set. A SHAP analysis of model features indicates the importance of hydrophobicity and molecular complexity as primary factors influencing the aggregation propensity. The BAD molecule filter is readily accessible for the public usage on https://molmodlab-aau.com/Tools.html. This filter provides a new, more robust tool for aggregate prediction in the early stages of drug discovery to optimize hit rates and reduce associated testing and validation overheads.


Assuntos
Descoberta de Drogas , Descoberta de Drogas/métodos , Coloides/química , Ensaios de Triagem em Larga Escala , Bibliotecas de Moléculas Pequenas/química
2.
Chem Biodivers ; 20(11): e202301176, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37861105

RESUMO

With the potential for coronaviruses to re-emerge and trigger future pandemics, the urgent development of antiviral inhibitors against SARS-CoV-2 is essential. The Mpro enzyme is crucial for disease progression and the virus's life cycle. It possesses allosteric sites that can hinder its catalytic activity, with some of these sites located at or near the dimerization interface. Among them, sites #2 and #5 possess druggable pockets and are predicted to bind drug-like molecules. Consequently, a commercially available ligand library containing ~7 million ligands was used to target site #2 via structure-based virtual screening. After extensive filtering, docking, and post-docking analyses, 53 compounds were chosen for biological testing. An oxindole derivative was identified as a Mpro non-competitive reversible inhibitor with a Ki of 115 µM and an IC50 of 101.9 µM. Throughout the 200 ns-long MD trajectories, our top hit has shown a very stable binding mode, forming several interactions with residues in sites #2 and #5. Moreover, derivatives of our top hit were acquired for biological testing to gain deeper insights into their structure-activity relationship. To sum up, drug-like allosteric inhibitors seem promising and can provide us with an additional weapon in our war against the recent pandemic, and possibly other coronaviruses-caused diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Antivirais/química , Oxindóis/farmacologia , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular
3.
Molecules ; 28(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37049763

RESUMO

The need for new antibiotics has become a major worldwide challenge as bacterial strains keep developing resistance to the existing drugs at an alarming rate. Enoyl-acyl carrier protein reductases (FabI) play a crucial role in lipids and fatty acid biosynthesis, which are essential for the integrity of the bacterial cell membrane. Our study aimed to discover small FabI inhibitors in continuation to our previously found hit MN02. The process was initially started by conducting a similarity search to the NCI ligand database using MN02 as a query. Accordingly, ten compounds were chosen for the computational assessment and antimicrobial testing. Most of the compounds showed an antibacterial activity against Gram-positive strains, while RK10 exhibited broad-spectrum activity against both Gram-positive and Gram-negative bacteria. All tested compounds were then docked into the saFabI active site followed by 100 ns MD simulations (Molecular Dynamics) and MM-GBSA (Molecular Mechanics with Generalised Born and Surface Area Solvation) calculations in order to understand their fitting and estimate their binding energies. Interestingly, and in line with the experimental data, RK10 was able to exhibit the best fitting with the target catalytic pocket. To sum up, RK10 is a small compound with leadlike characteristics that can indeed act as a promising candidate for the future development of broad-spectrum antibacterial agents.


Assuntos
Antibacterianos , Enoil-(Proteína de Transporte de Acila) Redutase (NADH) , Antibacterianos/farmacologia , Antibacterianos/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/metabolismo , Bactérias Gram-Negativas/metabolismo , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Positivas/metabolismo , Bactérias/metabolismo , Simulação de Dinâmica Molecular
4.
Int J Mol Sci ; 23(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35457286

RESUMO

Despite available treatments, breast cancer is the leading cause of cancer-related death. Knowing that the tyrosine phosphatase SHP2 is a regulator in tumorigenesis, developing inhibitors of SHP2 in breast cells is crucial. Our study investigated the effects of new compounds, purchased from NSC, on the phosphatase activity of SHP2 and the modulation of breast cancer cell lines' proliferation and viability. A combined ligand-based and structure-based virtual screening protocol was validated, then performed, against SHP2 active site. Top ranked compounds were tested via SHP2 enzymatic assay, followed by measuring IC50 values. Subsequently, hits were tested for their anti-breast cancer viability and proliferative activity. Our experiments identified three compounds 13030, 24198, and 57774 as SHP2 inhibitors, with IC50 values in micromolar levels and considerable selectivity over the analogous enzyme SHP1. Long MD simulations of 500 ns showed a very promising binding mode in the SHP2 catalytic pocket. Furthermore, these compounds significantly reduced MCF-7 breast cancer cells' proliferation and viability. Interestingly, two of our hits can have acridine or phenoxazine cyclic system known to intercalate in ds DNA. Therefore, our novel approach led to the discovery of SHP2 inhibitors, which could act as a starting point in the future for clinically useful anticancer agents.


Assuntos
Antineoplásicos , Neoplasias da Mama , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Domínio Catalítico , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Feminino , Humanos , Células MCF-7 , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores
5.
Molecules ; 27(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36235244

RESUMO

The main protease enzyme (Mpro) of SARS-CoV-2 is one of the most promising targets for COVID-19 treatment. Accordingly, in this work, a structure-based virtual screening of 3.8 million ligand libraries was carried out. After rigorous filtering, docking, and post screening assessments, 78 compounds were selected for biological evaluation, 3 of which showed promising inhibition of the Mpro enzyme. The obtained hits (CB03, GR04, and GR20) had reasonable potencies with Ki values in the medium to high micromolar range. Interestingly, while our most potent hit, GR20, was suggested to act via a reversible covalent mechanism, GR04 was confirmed as a noncompetitive inhibitor that seems to be one of a kind when compared to the other allosteric inhibitors discovered so far. Moreover, all three compounds have small sizes (~300 Da) with interesting fittings in their relevant binding sites, and they possess lead-like characteristics that can introduce them as very attractive candidates for the future development of COVID-19 treatments.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Antivirais/química , Antivirais/farmacologia , Domínio Catalítico , Proteases 3C de Coronavírus , Humanos , Ligantes , Simulação de Acoplamento Molecular , Inibidores de Proteases/química
6.
J Chem Inf Model ; 60(8): 3901-3909, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32628846

RESUMO

Small molecule compounds which form colloidal aggregates in solution are problematic in early drug discovery; adsorption of the target protein by these aggregates can lead to false positives in inhibition assays. In this work, we probe the molecular basis of this inhibitory mechanism using molecular dynamics simulations. Specifically, we examine in aqueous solution the adsorption of the enzymes ß-lactamase and PTP1B onto aggregates of the drug miconazole. In accordance with experiment, molecular dynamics simulations observe formation of miconazole aggregates as well as subsequent association of these aggregates with ß-lactamase and PTP1B. When complexed with aggregate, the proteins do not exhibit significant alteration in protein tertiary structure or dynamics on the microsecond time scale of the simulations, but they do indicate persistent occlusion of the protein active site by miconazole molecules. MD simulations further suggest this occlusion can occur via surficial interactions of protein with miconazole but also potentially by envelopment of the protein by miconazole. The heterogeneous polarity of the miconazole aggregate surface seems to underpin its activity as an invasive and nonspecific inhibitory agent. A deeper understanding of these protein/aggregate systems has implications not only for drug design but also for their exploitation as tools in drug delivery and analytical biochemistry.


Assuntos
Inibidores Enzimáticos , Simulação de Dinâmica Molecular , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Proteínas , beta-Lactamases/metabolismo
7.
Molecules ; 25(18)2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962260

RESUMO

This work demonstrates synthetic strategies for the incorporation of a synthesized pyrimidine glucagon-like peptide-1 (GLP-1) agonist into alginate-coated ZIF-8. The prepared pyrimidine GLP-1 agonist used for the treatment of diabetes type II, was trapped inside polymer coated ZIF-8. The encapsulation of the GLP-1 agonist was confirmed by UV-visible and FT-IR spectroscopies. Furthermore, the release kinetics of GLP-1 agonist drug from alginate-coated ZIF-8 were investigated in phosphate-buffered saline at 37 °C at pH 8 and 1.5. The alginate-coated ZIF-8 exhibited much faster drug release at basic pH than at pH 1.5, indicating the potential of the alginate-coated ZIF-8 system to overcome the fast degradation at acidic pH of the stomach and improve the drug's activity. This study may open the way for the synthesis of new metal organic frameworks (MOFs) to enhance drug delivery systems.


Assuntos
Alginatos/química , Preparações de Ação Retardada/química , Portadores de Fármacos/química , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Imidazóis/química , Estruturas Metalorgânicas/química , Pirimidinas/química , Alginatos/metabolismo , Glicemia/metabolismo , Materiais Revestidos Biocompatíveis/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Composição de Medicamentos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Pirimidinas/farmacologia , Zinco/química , Zinco/metabolismo
8.
Bioorg Chem ; 86: 393-400, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30763886

RESUMO

In this study, the acid chlorides of pyrazolo[3,4-d]pyrimidine compounds were prepared and reacted with a number of nucleophiles. The novel compounds were experimentally tested via enzyme assay and they showed cyclooxygenase-2 inhibition activity in the middle micro molar range (4b had a COX-1 IC50 of 26 µM and a COX-2 IC50 of 34 µM, 3b had a COX-1 IC50 of 19 µM and a COX-2 IC50 of 31 µM, 3a had a COX-2 IC50 of 42 µM). These compounds were analyzed via docking and were predicted to interact with some of the COX-2 key residues. Our best hit, 4d (COX-1 IC50 of 28 µM, COX-2 IC50 of 23 µM), appears to adopt similar binding modes to the standard COX-2 inhibitor, celecoxib, proposing room for possible selectivity. Additionally, the resultant novel compounds were tested in several in vivo assays. Four compounds 3a (COX-2 IC50 of 42 µM), 3d, 4d and 4f were notable for their anti-inflammatory activity that was comparable to that of the clinically available COX-2 inhibitor celecoxib. Interestingly, they showed greater potency than the famous non-steroidal anti-inflammatory drug, Diclofenac sodium. In summary, these novel pyrazolo[3,4-d]pyrimidine analogues showed interesting anti-inflammatory activity and could act as a starting point for future drugs.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Edema/tratamento farmacológico , Granuloma/tratamento farmacológico , Inflamação/tratamento farmacológico , Pirazóis/farmacologia , Pirimidinas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Carragenina , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/síntese química , Inibidores de Ciclo-Oxigenase/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Granuloma/induzido quimicamente , Humanos , Inflamação/induzido quimicamente , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Ratos , Ratos Wistar , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Terebintina
9.
J Enzyme Inhib Med Chem ; 34(1): 1373-1379, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31347933

RESUMO

Butyrylcholinesterase (BChE) plays an important role in the progression of the Alzheimer's disease. In this study, we used a structure-based virtual screening (VS) approach to discover new BChE inhibitors. A ligand database was filtered and docked to the BChE protein using Glide program. The outcome from VS was filtered and the top ranked hits were thoroughly examined for their fitting into the protein active site. Consequently, the best 38 hits were selected for in vitro testing using Ellman's method, and six of which showed inhibition activity for BChE. Interestingly, the most potent hit (Compound 4) exhibited inhibitory activity against the BChE enzyme in the low micromolar level with an IC50 value of 8.3 µM. Hits obtained from this work can act as a starting point for future SAR studies to discover new BChE inhibitors as anti-Alzheimer agents.


Assuntos
Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Descoberta de Drogas/métodos , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Inibidores da Colinesterase/química , Humanos , Ligantes , Estrutura Molecular , Relação Estrutura-Atividade
10.
J Mol Graph Model ; 127: 108672, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37992552

RESUMO

The main protease (Mpro) enzyme has an imperative function in disease progression and the life cycle of the SARS-CoV-2 virus. Although the orally active drug nirmatrelvir (co-administered with ritonavir as paxlovid) has been approved for emergency use as the frontline antiviral agent, there are a number of limitations that necessitate the discovery of new drug scaffolds, such as poor pharmacokinetics and susceptibility to proteolytic degradation due to its peptidomimetic nature. This study utilized a novel virtual screening workflow that combines pharmacophore modelling, multiple-receptor covalent docking, and biological evaluation in order to find new Mpro inhibitors. After filtering and analysing ∼66,000 ligands from three different electrophilic libraries, 29 compounds were shortlisted for experimental testing, and two of them exhibited ≥20% inhibition at 100 µM. Our top candidate, GF04, is a benzylpyrrolyl compound that exhibited the highest inhibition activity of 38.3%, with a relatively small size (<350 Da) and leadlike character. Interestingly, our approach also identified another hit, DR07, a pyrimidoindol with a non-peptide character, and a molecular weight of 438.9 Da, reporting an inhibition of 26.3%. The established approach detailed in this study, in conjunction with the discovered inhibitors, has the capacity to yield novel perspectives for devising covalent inhibitors targeting the COVID-19 Mpro enzyme and other comparable targets.


Assuntos
COVID-19 , Farmacóforo , Humanos , SARS-CoV-2 , Proteases 3C de Coronavírus , Antivirais/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia
11.
Healthcare (Basel) ; 11(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36833001

RESUMO

Patients infected with coronavirus have new experiences and hence new needs from the healthcare sector. Acknowledging patients' experiences can exhibit promising outcomes in coronavirus management. Pharmacists are considered a vital pillar in managing patients' experiences during their infection. A cross-sectional study was conducted to assess the experiences of COVID-19-infected individuals and the roles of pharmacists in the United Arab Emirates. The survey was face- and content-validated after being developed. Three sections were included in the survey (demographics, experiences of infected individuals, and the roles of pharmacists). Data were analyzed using the Statistical Package for the Social Sciences. The study participants (n = 509) had a mean age of 34.50 (SD = 11.93). The most reported symptoms among participants were fatigue (81.5%), fever (76.8%), headache (76.6%), dry cough (74.1%), muscle or joint pain (70.7%), and sore throat (68.6%). Vitamin C was the most used supplement (88.6%), followed by pain relievers (78.2%). Female gender was the only factor associated with symptom severity. About 79.0% agreed that the pharmacist played an important and effective role during their infection. The most reported symptom was fatigue, with females reporting more severe symptoms. The role of the pharmacist proved to be vital during this pandemic.

12.
Drug Des Devel Ther ; 16: 2463-2478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35941927

RESUMO

The current pandemic caused by the COVID-19 disease has reached everywhere in the world and has affected every aspect of our lives. As of the current data, the World Health Organization (WHO) has reported more than 300 million confirmed COVID-19 cases worldwide and more than 5 million deaths. Mpro is an enzyme that plays a key role in the life cycle of the SARS-CoV-2 virus, and it is vital for the disease progression. The Mpro enzyme seems to have several allosteric sites that can hinder the enzyme catalytic activity. Furthermore, some of these allosteric sites are located at or nearby the dimerization interface which is essential for the overall Mpro activity. In this review paper, we investigate the potential of the Mpro allosteric site to act as a drug target, especially since they interestingly appear to be resistant to mutation. The work is illustrated through three subsequent sections: First, the two main categories of Mpro allosteric sites have been explained and discussed. Second, a total of six pockets have been studied and evaluated for their druggability and cavity characteristics. Third, the experimental and computational attempts for the discovery of new allosteric inhibitors have been illustrated and discussed. To sum up, this review paper gives a detailed insight into the feasibility of developing new Mpro inhibitors to act as a potential treatment for the COVID-19 disease.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Sítio Alostérico , Antivirais/química , Antivirais/farmacologia , Sítios de Ligação , Proteases 3C de Coronavírus , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/metabolismo
13.
Sci Rep ; 12(1): 7975, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562538

RESUMO

The featureless interface formed by protein-protein interactions (PPIs) is notorious for being considered a difficult and poorly druggable target. However, recent advances have shown PPIs to be druggable, with the discovery of potent inhibitors and stabilizers, some of which are currently being clinically tested and approved for medical use. In this study, we assess the druggability of 12 commonly targeted PPIs using the computational tool, SiteMap. After evaluating 320 crystal structures, we find that the PPI binding sites have a wide range of druggability scores. This can be attributed to the unique structural and physiochemical features that influence their ligand binding and concomitantly, their druggability predictions. We then use these features to propose a specific classification system suitable for assessing PPI targets based on their druggability scores and measured binding-affinity. Interestingly, this system was able to distinguish between different PPIs and correctly categorize them into four classes (i.e. very druggable, druggable, moderately druggable, and difficult). We also studied the effects of protein flexibility on the computed druggability scores and found that protein conformational changes accompanying ligand binding in ligand-bound structures result in higher protein druggability scores due to more favorable structural features. Finally, the drug-likeness of many published PPI inhibitors was studied where it was found that the vast majority of the 221 ligands considered here, including orally tested/marketed drugs, violate the currently acceptable limits of compound size and hydrophobicity parameters. This outcome, combined with the lack of correlation observed between druggability and drug-likeness, reinforces the need to redefine drug-likeness for PPI drugs. This work proposes a PPI-specific classification scheme that will assist researchers in assessing the druggability and identifying inhibitors of the PPI interface.


Assuntos
Proteínas , Sítios de Ligação , Ligantes , Ligação Proteica , Proteínas/metabolismo
14.
Pharm Pract (Granada) ; 20(4): 2723, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36793904

RESUMO

Background: Patients' adherence to medication can be assessed by several subjective or objective methods. The Global Initiative for Asthma (GINA) has recommended the use of both measures simultaneously. Objective: To assess patients' adherence to medication using a subjective or an objective method separately, and via using a combination of both methods. As well as identifying the degree of agreement between the two methods. Methods: Participants who met the study inclusion criteria completed the Adherence to Asthma Medication Questionnaire (AAMQ). A retrospective audit was conducted in order to extract pharmacy refill records for the previous twelve months. The patients' pharmacy refill records were expressed using the Medication Possession Ratio (MPR). Data were analyzed using the Statistical Package for Social Science. The degree of agreement was determined by Cohen's kappa coefficient (κ). Results: In terms of the difference in the ability of each method to identify non-adherent patients, a higher percentage of non-adherent patients were identified using the self-reported AAMQ (61.4%) compared to the pharmacy refill records (34.3%). When both methods, in combination, were used to assess adherence, the percentage of non-adherent patients was 80.0%, which is higher than each method when used separately. Twenty percent of the patients were considered adherent on both assessment methods, while 15.7% were considered non-adherent via both methods. Consequently, the AAMQ and pharmacy refill records agreed on 35.7% of the patients. The degree of agreement analysis showed a low correlation between the two methods. Conclusion: The combination strategy resulted in a higher percentage of non-adherent patients, compared to using a subjective (the AAMQ) or an objective (the pharmacy refill records) method. The GINA guideline proposition may be supported by the present study's findings.

15.
Acta Pharm ; 71(3): 325-333, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36654095

RESUMO

COVID-19 was declared a pandemic by the World Health Organization (WHO) in March 2020. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2). The aim of this study is to target the SARS-CoV-2 virus main protease (Mpro) via structure-based virtual screening. Consequently, > 580,000 ligands were processed via several filtration and docking steps, then the top 21 compounds were analysed extensively via MM-GBSA scoring and molecular dynamic simulations. Interestingly, the top compounds showed favorable binding energies and binding patterns to the protease enzyme, forming interactions with several key residues. Trihydroxychroman and pyrazolone derivatives, SN02 and SN18 ligands, exhibited very promising binding modes along with the best MM-GBSA scoring of -40.9 and -41.2 kcal mol-1, resp. MD simulations of 300 ns for the ligand-protein complexes of SN02 and SN18 affirmed the previously attained results of the potential inhibition activity of these two ligands. These potential inhibitors can be the starting point for further studies to pave way for the discovery of new antiviral drugs for SARS-CoV-2.

16.
J Mol Graph Model ; 92: 44-54, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31306865

RESUMO

The ɑ7 receptor is a member in the nicotinic acetylcholine receptor (nAChR) which has been implicated in several neurological disorders. Beside normal agonists and antagonists of α7 nAChRs, several studies revealed other types of molecules that are able to activate or deactivate ɑ7 receptors via allosteric binding; those are called positive allosteric modulators (PAMs) or negative allosteric modulators (NAMs), with the former having more pharmacological importance than the latter. Since both types of modulators are believed to bind to the same place in the intracavity of the transmembrane domain, it was important to differentiate between them in terms of structural features and their binding with the target receptor, and then use these specific characteristics as filters to discriminate PAMs from NAMS. To do that, modulators' physicochemical properties were investigated using two databases of known PAMs or NAMs which were then used to elucidate a specific pharmacophore for each class. Interestingly, PAMs were found to be relatively larger and more polar compared to NAMs, which was observed to carry a positive charge with double the number of cases than PAMs. Furthermore. a pharmacophore for each class was developed and the best PAMs pharmacophore was successfully able to pass 94% of tested PAMs and to eliminate 71% of NAMs, while the best NAM pharmacophore was able to pass 82% of NAMs and to filter out 85% of PAMs. Docking these known modulators into the α7 nAChRs allosteric site identified several amino acids that are key for specifically binding PAMs compared to NAMs. Next, these findings were employed in virtual screening and then seeding experiments were conducted to validate the developed pharmacophores usage as filters prior to the final docking. Interestingly, the number of retrieved PAMs in the final docking list was improved by up to five-fold compared to the non-filtered protocol, which clearly indicates for the efficiency of our protocol to pick true PAMs over decoys. Hence, the pharmacophore-based filtering technique developed in this work can act as a valuable tool in the pursuit of new, potent PAM molecules as therapeutically useful modulators of the α7 nicotinic receptors.


Assuntos
Sítio Alostérico , Modelos Moleculares , Agonistas Nicotínicos/química , Antagonistas Nicotínicos/química , Receptor Nicotínico de Acetilcolina alfa7/química , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico/efeitos dos fármacos , Sítios de Ligação , Fenômenos Químicos , Descoberta de Drogas , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes
17.
Chem Biol Drug Des ; 94(2): 1545-1555, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31063658

RESUMO

The need for new antibacterial agents is increasingly becoming of great importance as bacterial resistance to current drugs is quickly spreading. Enoyl-acyl carrier protein reductases (FabI) are important enzymes for fatty acid biosynthesis in bacteria and other micro-organisms. In this project, we conducted structure-based virtual screening against the FabI enzyme, and accordingly, 37 compounds were selected for experimental testing. Interestingly, five compounds were able to demonstrate antimicrobial effect with variable inhibition activity against various strains of bacteria and fungi. Minimum inhibitory concentrations of the active compounds were determined and showed to be in low to medium micromolar range. Subsequently, enzyme inhibition assay was carried out for our five antimicrobial hits to confirm their biological target and determine their IC50 values. Three of these tested compounds exhibited inhibition activity for the FabI enzyme where our best hit MN02 had an IC50 value of 7.8 µM. Furthermore, MN02 is a small bisphenolic compound that is predicted to have all required features to firmly bind with the target enzyme. To sum up, hits discovered in this work can act as a good starting point for the future development of new and potent antimicrobial agents.


Assuntos
Antibacterianos , Bactérias/enzimologia , Proteínas de Bactérias/antagonistas & inibidores , Desenho de Fármacos , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/antagonistas & inibidores , Inibidores Enzimáticos , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia
18.
Bioorg Med Chem Lett ; 18(3): 1217-22, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18083027

RESUMO

Src signalling and transduction are directly involved in cell growth, cell cycle, malignant transformation and cell migration, providing therapeutic opportunities through inhibition of Src. Here we report virtual screening for novel compounds that inhibit the Src-SH3 protein-protein interaction with a proline-rich peptide ligand. Computational docking of the ZINC compound database was performed using GOLD. Top-scoring compounds were assayed using a fluorescence polarization-based assay. A benzoquinoline derivative showed micromolar inhibition of binding between Src-SH3 and the proline-rich peptide. Several analogues were subsequently assayed showing the requirement of a linker between the benzoquinoline and phenyl rings, and electron donating substituents on the phenyl ring.


Assuntos
Prolina/química , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Quinolinas/síntese química , Sequência de Aminoácidos , Técnicas de Química Combinatória , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Modelos Moleculares , Ligação Proteica , Quinolinas/química , Quinolinas/farmacologia , Relação Estrutura-Atividade
19.
Drug Des Devel Ther ; 12: 3741-3752, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464405

RESUMO

BACKGROUND: The tumor suppressor protein p53 plays an important role in preventing tumor formation and progression through its involvement in cell division control and initiation of apoptosis. Mdm2 protein controls the activity of p53 protein through working as ubiquitin E3 ligase promoting p53 degradation through the proteasome degradation pathway. Inhibitors for Mdm2-p53 interaction have restored the activity of p53 protein and induced cancer fighting properties in the cell. PURPOSE: The objective of this study is to use computer-aided drug discovery techniques to search for new Mdm2-p53 interaction inhibitors. METHODS: A set of pharmacophoric features were created based on a standard Mdm2 inhibitor and this was used to screen a commercial drug-like ligand library; then potential inhibitors were docked and ranked in a multi-step protocol using GLIDE. Top ranked ligands from docking were evaluated for their inhibition activity of Mdm2-p53 interaction using ELISA testing. RESULTS: Several compounds showed inhibition activity at the submicromolar level, which is comparable to the standard inhibitor Nutlin-3a. Furthermore, the discovered inhibitors were evaluated for their anticancer activities against different breast cancer cell lines, and they showed an interesting inhibition pattern. CONCLUSION: The reported inhibitors can represent a starting point for further SAR studies in the future and can help in the discovery of new anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Pirimidinas/farmacologia , Triazóis/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Desenho Assistido por Computador , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirimidinas/síntese química , Pirimidinas/química , Triazóis/síntese química , Triazóis/química , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo
20.
ChemMedChem ; 13(6): 500-506, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29058775

RESUMO

The presence of false positives in enzyme inhibition assays is a common problem in early drug discovery, especially for compounds that form colloid aggregates in solution. The molecular basis of these aggregates could not be thoroughly explored because of their transient stability. In this study we conducted comparative molecular dynamics (MD) simulations of miconazole, a strong aggregator, and fluconazole, a known non-aggregator. Interestingly, miconazole displays full aggregation within only 50 ns, whilst fluconazole shows no aggregation over the 500 ns simulation. The simulations indicate that the center of the aggregate is densely packed by the hydrophobic groups of miconazole, whereas polar and nonpolar groups comprise the surface to form a micelle-like colloid. The amphiphilic moment and planar nature of the miconazole structure appear to promote its aggregating behavior. The simulations also predict rapid aggregate formation for a second known promiscuous inhibitor, nicardipine. Thus, MD appears to be a useful tool to characterize aggregate-prone inhibitors at molecular-level detail and has the potential to provide useful information for drug discovery and formulation design.


Assuntos
Inibidores Enzimáticos/farmacologia , Enzimas/metabolismo , Fluconazol/farmacologia , Miconazol/farmacologia , Simulação de Dinâmica Molecular , Coloides/química , Desenho de Fármacos , Descoberta de Drogas , Inibidores Enzimáticos/química , Reações Falso-Positivas , Fluconazol/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , Miconazol/química , Estrutura Molecular , Soluções , Especificidade por Substrato
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA