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1.
Arch Pharm (Weinheim) ; 357(2): e2300426, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37991233

RESUMO

Heterocyclic pharmacophores such as thiazole and quinoline rings have a significant role in medicinal chemistry. They are considered privileged structures since they constitute several Food and Drug Administration (FDA)-approved drugs for cancer treatment. Herein, we report the synthesis, in silico evaluation of the ADMET profiles, and in vitro investigation of the anticancer activity of a series of novel thiazolyl-hydrazones based on the 8-quinoline (1a-c), 2-quinoline (2a-c), and 8-hydroxy-2-quinolyl moiety (3a-c). The panel of several human cancer cell lines and the nontumorigenic human embryonic kidney cell line HEK-293 were used to evaluate the compound-mediated in vitro anticancer activities, leading to [2-(2-(quinolyl-8-ol-2-ylmethylene)hydrazinyl)]-4-(4-methoxyphenyl)-1,3-thiazole (3c) as the most promising compound. The study revealed that 3c blocks the cell-cycle progression of a human colon cancer cell line (HCT-116) in the S phase and induces DNA double-strand breaks. Also, our findings demonstrate that 3c accumulates in lysosomes, ultimately leading to the cell death of the hepatocellular carcinoma cell line (Hep-G2) and HCT-116 cells, by the mechanism of autophagy inhibition.


Assuntos
Antineoplásicos , Neoplasias , Quinolinas , Humanos , Hidrazonas , Relação Estrutura-Atividade , Células HEK293 , Ensaios de Seleção de Medicamentos Antitumorais , Quinolinas/farmacologia , Quinolinas/química , Tiazóis , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células
2.
New Phytol ; 239(1): 146-158, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36978283

RESUMO

Protein phosphorylation is a major molecular switch involved in the regulation of stomatal opening and closure. Previous research defined interaction between MAP kinase 12 and Raf-like kinase HT1 as a required step for stomatal movements caused by changes in CO2 concentration. However, whether MPK12 kinase activity is required for regulation of CO2 -induced stomatal responses warrants in-depth investigation. We apply genetic, biochemical, and structural modeling approaches to examining the noncatalytic role of MPK12 in guard cell CO2 signaling that relies on allosteric inhibition of HT1. We show that CO2 /HCO3 - -enhanced MPK12 interaction with HT1 is independent of its kinase activity. By analyzing gas exchange of plant lines expressing various kinase-dead and constitutively active versions of MPK12 in a plant line where MPK12 is deleted, we confirmed that CO2 -dependent stomatal responses rely on MPK12's ability to bind to HT1, but not its kinase activity. We also demonstrate that purified MPK12 and HT1 proteins form a heterodimer in the presence of CO2 /HCO3 - and present structural modeling that explains the MPK12:HT1 interaction interface. These data add to the model that MPK12 kinase-activity-independent interaction with HT1 functions as a molecular switch by which guard cells sense changes in atmospheric CO2 concentration.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fosforilação , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dióxido de Carbono/metabolismo , Mutação , Estômatos de Plantas/fisiologia
3.
Langmuir ; 39(32): 11398-11405, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37523487

RESUMO

The diffusive processes that occur in minerals involve chemical and physical surface phenomena of great interest that allow for understanding the mobility of different anions of environmental importance. One of them is glyphosate, which is widely used as a pesticide. In this work, we performed Hubbard-corrected density functional theory (DFT + U) calculations to study the adsorption and surface diffusion of methylphosphonic acid (MPA), as a model of glyphosate, on the (010) plane of goethite (GOT), one of the most important Fe(III) minerals in soils and sediments. In particular, the MPA adsorption was studied at the GOT-water interface, finding a strong covalent character in the bond. We also corroborated the occurrence of double proton transfer (MPA to GOT and GOT to GOT). Finally, activation energy barriers were calculated to estimate the half-lives for molecular diffusion, showing that MPA moves almost 3000 times slower than water at the GOT surface.

4.
Org Biomol Chem ; 20(23): 4724-4735, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35612321

RESUMO

Research on human milk oligosaccharides (HMOs) has increased over the past decade showing great interest in their beneficial effects. Here we describe a method for the selective deacetylation using immobilised Candida antarctica lipase-B, Novozyme N435 (N435), of pyranose saccharides in organic media with the aim of simplifying and improving the pathways for the synthesis of HMOs. By first studying in depth the deacetylation reaction of peracetylated D-glucose two reaction conditions were found, which were used on different HMO building blocks, peracetylated saccharides and thioglycosides. D-Glucose based saccharides showed selectivity towards the fourth and the sixth position deacetylation. While α-anomer of peracetylated D-galactose remained unreactive and ß-anomer favoured the first position deacetylation. Peracetylated L-fucose, on the other hand, had no selectivity as the main product was fully unprotected L-fucose. Taking the peracetylated D-glucose deacetylation reaction product and selectively protecting the primary hydroxyl group in the sixth position left only the fourth position open for the glycosylation. Meanwhile, the deacetylation product of D-galactose thioglycoside, with the sixth position deacetylated, had both acceptor and donor capabilities. Using the two aforementioned products derived from the N435 deacetylation reactions a deviant HMO, 6'-galactosyllactose (6'-GL) was synthesised.


Assuntos
Fucose , Lactose/metabolismo , Leite Humano , Basidiomycota , Carboidratos , Galactose , Glucose , Humanos , Lipase , Oligossacarídeos
5.
Drug Resist Updat ; 52: 100713, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32615525

RESUMO

Overcoming multidrug resistance represents a major challenge for cancer treatment. In the search for new chemotherapeutics to treat malignant diseases, drug repurposing gained a tremendous interest during the past years. Repositioning candidates have often emerged through several stages of clinical drug development, and may even be marketed, thus attracting the attention and interest of pharmaceutical companies as well as regulatory agencies. Typically, drug repositioning has been serendipitous, using undesired side effects of small molecule drugs to exploit new disease indications. As bioinformatics gain increasing popularity as an integral component of drug discovery, more rational approaches are needed. Herein, we show some practical examples of in silico approaches such as pharmacophore modelling, as well as pharmacophore- and docking-based virtual screening for a fast and cost-effective repurposing of small molecule drugs against multidrug resistant cancers. We provide a timely and comprehensive overview of compounds with considerable potential to be repositioned for cancer therapeutics. These drugs are from diverse chemotherapeutic classes. We emphasize the scope and limitations of anthelmintics, antibiotics, antifungals, antivirals, antimalarials, antihypertensives, psychopharmaceuticals and antidiabetics that have shown extensive immunomodulatory, antiproliferative, pro-apoptotic, and antimetastatic potential. These drugs, either used alone or in combination with existing anticancer chemotherapeutics, represent strong candidates to prevent or overcome drug resistance. We particularly focus on outcomes and future perspectives of drug repositioning for the treatment of multidrug resistant tumors and discuss current possibilities and limitations of preclinical and clinical investigations.


Assuntos
Antineoplásicos/farmacologia , Reposicionamento de Medicamentos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Biologia Computacional , Simulação por Computador , Descoberta de Drogas/métodos , Humanos , Neoplasias/patologia
6.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206613

RESUMO

Many chemicals that enter the environment, food chain, and the human body can disrupt androgen-dependent pathways and mimic hormones and therefore, may be responsible for multiple diseases from reproductive to tumor. Thus, modeling and predicting androgen receptor activity is an important area of research. The aim of the current study was to find a method or combination of methods to predict compounds that can bind to and/or disrupt the androgen receptor, and thereby guide decision making and further analysis. A stepwise procedure proceeded from analysis of protein structures from human, chimp, and rat, followed by docking and subsequent ligand, and statistics based techniques that improved classification gradually. The best methods used multivariate logistic regression of combinations of chimpanzee protein structural docking scores, extended connectivity fingerprints, and naïve Bayesians of known binders and non-binders. Combination or consensus methods included data from a variety of procedures to improve the final model accuracy.


Assuntos
Teorema de Bayes , Disruptores Endócrinos/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Receptores Androgênicos/química , Disruptores Endócrinos/metabolismo , Humanos , Ligantes , Modelos Logísticos , Estrutura Molecular , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Curva ROC , Receptores Androgênicos/metabolismo , Reprodutibilidade dos Testes
7.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638841

RESUMO

Since many of the currently available antileishmanial treatments exhibit toxicity, low effectiveness, and resistance, search and validation of new therapeutic targets allowing the development of innovative drugs have become a worldwide priority. This work presents a structure-based drug discovery strategy to validate the Lmj_04_BRCT domain as a novel therapeutic target in Leishmania spp. The structure of this domain was explored using homology modeling, virtual screening, and molecular dynamics studies. Candidate compounds were validated in vitro using promastigotes of Leishmania major, L. amazonensis, and L. infantum, as well as primary mouse macrophages infected with L. major. The novel inhibitor CPE2 emerged as the most active of a group of compounds against Leishmania, being able to significantly reduce the viability of promastigotes. CPE2 was also active against the intracellular forms of the parasites and significantly reduced parasite burden in murine macrophages without exhibiting toxicity in host cells. Furthermore, L. major promastigotes treated with CPE2 showed significant lower expression levels of several genes (α-tubulin, Cyclin CYCA, and Yip1) related to proliferation and treatment resistance. Our in silico and in vitro studies suggest that the Lmj_04_BRCT domain and its here disclosed inhibitors are new potential therapeutic options against leishmaniasis.


Assuntos
Antiprotozoários , Leishmania major/metabolismo , Leishmaniose Cutânea/tratamento farmacológico , Proteínas de Protozoários/antagonistas & inibidores , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Antiprotozoários/farmacologia , Feminino , Leishmaniose Cutânea/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos , Proteínas de Protozoários/metabolismo
8.
Molecules ; 26(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652992

RESUMO

Substances that can modify the androgen receptor pathway in humans and animals are entering the environment and food chain with the proven ability to disrupt hormonal systems and leading to toxicity and adverse effects on reproduction, brain development, and prostate cancer, among others. State-of-the-art databases with experimental data of human, chimp, and rat effects by chemicals have been used to build machine-learning classifiers and regressors and to evaluate these on independent sets. Different featurizations, algorithms, and protein structures lead to different results, with deep neural networks (DNNs) on user-defined physicochemically relevant features developed for this work outperforming graph convolutional, random forest, and large featurizations. The results show that these user-provided structure-, ligand-, and statistically based features and specific DNNs provided the best results as determined by AUC (0.87), MCC (0.47), and other metrics and by their interpretability and chemical meaning of the descriptors/features. In addition, the same features in the DNN method performed better than in a multivariate logistic model: validation MCC = 0.468 and training MCC = 0.868 for the present work compared to evaluation set MCC = 0.2036 and training set MCC = 0.5364 for the multivariate logistic regression on the full, unbalanced set. Techniques of this type may improve AR and toxicity description and prediction, improving assessment and design of compounds. Source code and data are available on github.


Assuntos
Aprendizado Profundo , Ligação Proteica/genética , Proteínas/genética , Receptores Androgênicos/genética , Algoritmos , Animais , Humanos , Ligantes , Modelos Logísticos , Redes Neurais de Computação , Ratos , Software
9.
Molecules ; 26(18)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34577052

RESUMO

Multiple myeloma is an incurable plasma cell neoplastic disease representing about 10-15% of all haematological malignancies diagnosed in developed countries. Proteasome is a key player in multiple myeloma and proteasome inhibitors are the current first-line of treatment. However, these are associated with limited clinical efficacy due to acquired resistance. One of the solutions to overcome this problem is a polypharmacology approach, namely combination therapy and multitargeting drugs. Several polypharmacology avenues are currently being explored. The simultaneous inhibition of EZH2 and Proteasome 20S remains to be investigated, despite the encouraging evidence of therapeutic synergy between the two. Therefore, we sought to bridge this gap by proposing a holistic in silico strategy to find new dual-target inhibitors. First, we assessed the characteristics of both pockets and compared the chemical space of EZH2 and Proteasome 20S inhibitors, to establish the feasibility of dual targeting. This was followed by molecular docking calculations performed on EZH2 and Proteasome 20S inhibitors from ChEMBL 25, from which we derived a predictive model to propose new EZH2 inhibitors among Proteasome 20S compounds, and vice versa, which yielded two dual-inhibitor hits. Complementarily, we built a machine learning QSAR model for each target but realised their application to our data is very limited as each dataset occupies a different region of chemical space. We finally proceeded with molecular dynamics simulations of the two docking hits against the two targets. Overall, we concluded that one of the hit compounds is particularly promising as a dual-inhibitor candidate exhibiting extensive hydrogen bonding with both targets. Furthermore, this work serves as a framework for how to rationally approach a dual-targeting drug discovery project, from the selection of the targets to the prediction of new hit compounds.


Assuntos
Descoberta de Drogas , Mieloma Múltiplo , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Proteínas Oncogênicas , Inibidores de Proteassoma/farmacologia
10.
Int J Mol Sci ; 21(10)2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32456148

RESUMO

Plants have been used for centuries to treat several illnesses. The Plectranthus genus has a vast variety of species that has allowed the isolation of cytotoxic compounds with notable activities. The abietane diterpenes 6,7-dehydroroyleanone (DeRoy, 1), 7α-acetoxy-6ß-hydroxyroyleanone (Roy, 2), and Parvifloron D (ParvD, 3) were obtained from Plectranthus spp. and showed promising biological activities, such as cytotoxicity. The inhibitory effects of the different natural abietanes (1-3) were compared in MFC7, SkBr3, and SUM159 cell lines, as well as SUM159 grown in cancer stem cell-inducing conditions. Based on the royleanones' bioactivity, the derivatives RoyBz (4), RoyBzCl (5), RoyPr2 (6), and DihydroxyRoy (7), previously obtained from 2, were selected for further studies. Protein kinases C (PKCs) are involved in several carcinogenic processes. Thus, PKCs are potential targets for cancer therapy. To date, the portfolio of available PKC modulators remains very limited due to the difficulty of designing isozyme-selective PKC modulators. As such, molecular docking was used to evaluate royleanones 1-6 as predicted isozyme-selective PKC binders. Subtle changes in the binding site of each PKC isoform change the predicted interaction profiles of the ligands. Subtle changes in royleanone substitution patterns, such as a double substitution only with non-substituted phenyls, or hydroxybenzoate at position four that flips the binding mode of ParvD (3), can increase the predicted interactions in certain PKC subtypes.


Assuntos
Abietanos/química , Antineoplásicos/química , Proteína Quinase C/metabolismo , Abietanos/farmacologia , Antineoplásicos/farmacologia , Sítios de Ligação , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Células MCF-7 , Simulação de Acoplamento Molecular , Ligação Proteica , Proteína Quinase C/química
12.
Rev Chil Pediatr ; 91(2): 226-231, 2020 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32730541

RESUMO

INTRODUCTION: Cord blood (CB) as a source of Hematopoietic Stem Cells for Transplantation (HSCT) is well established. Worldwide, nonetheless, less than 10% of the CB HSCTs are performed with a match sibling donor. Since 2004, the Chilean National Childhood Cancer Program (PINDA) net work, has established a CB directed donation program for HSCT. PATIENTS AND METHOD: An obser vational, descriptive and retrospective study was designed to assess the number and characteristics of the CB units collected in the program as well as the number, clinical characteristics and follow-up of the patients who received an HSCT from those CB units between January 2004 and October 2018. RESULTS: Sixty CB units have been collected; 55 of them with full records and stored. The median volume collected was 74.8 ml (30.0-170.8), the median number of total nucleated cells was 7.6 x 10e8 (2.0-21.1), and the median of CD34+ cells was 1.6 x 10e6 (0.2-11.6). Four high-risk leukemia patients received HSCT, all of them developed severe complications after transplantation and one patient died due to relapse. Those patients currently alive have a 100% Karnofsky/Lansky score. The median follow-up time was 8 years. CONCLUSION: The PINDA program has allowed 4 patients to be transplan ted who otherwise would not have had access to a donor. This directed donation program could be seen as a model for the development of a public cord blood bank in Chile.


Assuntos
Doadores de Sangue , Doação Dirigida de Tecido , Sangue Fetal , Transplante de Células-Tronco Hematopoéticas , Irmãos , Adolescente , Criança , Pré-Escolar , Chile , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Programas Nacionais de Saúde , Avaliação de Resultados em Cuidados de Saúde , Saúde Pública , Estudos Retrospectivos
13.
Ann Oncol ; 30(2): 236-242, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590484

RESUMO

BACKGROUND: For primary triple-negative breast cancer (TNBC) treated with neoadjuvant chemotherapy (NAC), higher pretreatment tumor-infiltrating lymphocytes (TILs) correlates with increased pathologic complete response (pCR) rates, and improved survival. We evaluated the added prognostic value of residual disease (RD) TILs to residual cancer burden (RCB) in predicting survival post-NAC. PATIENTS AND METHODS: We combined four TNBC NAC patient cohorts who did not achieve pCR. RD TILs were investigated for associations with recurrence-free survival (RFS), and overall survival (OS) using Cox models with stromal TILs as a continuous variable (per 10% increment). The likelihood ratio test was used to evaluate added prognostic value of RD TILs. RESULTS: A total of 375 RD TNBC samples were evaluable for TILs and RCB. The median age was 50 years, with 62% receiving anthracycline/taxane chemotherapy. The RCB class after NAC was 11%, 50%, and 39% for I, II, and III, respectively. The median RD TIL level was 20% (IQR 10-40). There was a positive correlation between RD TIL levels and CD8+ T-cell density (ρ = 0.41). TIL levels were significantly lower with increasing post-NAC tumor (P = 0.005), nodal stage (P = 0.032), but did not differ by RCB class (P = 0.84). Higher RD TILs were significantly associated with improved RFS (HR: 0.86; 95% CI 0.79-0.92; P < 0.001), and improved OS (HR: 0.87; 95% CI 0.80-0.94; P < 0.001), and remained significant predictors in multivariate analysis (RFS P = 0.032; OS P = 0.038 for OS). RD TILs added significant prognostic value to multivariate models including RCB class (P < 0.001 for RFS; P = 0.021 for OS). The positive prognostic effect of RD TILs significantly differed by RCB class for RFS (PInt=0.003) and OS (PInt=0.008) with a greater magnitude of positive effect observed for RCB class II than class III. CONCLUSIONS: TIL levels in TNBC RD are significantly associated with improved RFS and OS and add further prognostic information to RCB class, particularly in RCB class II.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos do Interstício Tumoral/imunologia , Terapia Neoadjuvante/mortalidade , Neoplasia Residual/patologia , Neoplasias de Mama Triplo Negativas/patologia , Idoso , Linfócitos T CD8-Positivos/imunologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/imunologia , Prognóstico , Receptor ErbB-2/metabolismo , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/imunologia
14.
PLoS Biol ; 14(12): e2000322, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27923039

RESUMO

Plant gas exchange is regulated by guard cells that form stomatal pores. Stomatal adjustments are crucial for plant survival; they regulate uptake of CO2 for photosynthesis, loss of water, and entrance of air pollutants such as ozone. We mapped ozone hypersensitivity, more open stomata, and stomatal CO2-insensitivity phenotypes of the Arabidopsis thaliana accession Cvi-0 to a single amino acid substitution in MITOGEN-ACTIVATED PROTEIN (MAP) KINASE 12 (MPK12). In parallel, we showed that stomatal CO2-insensitivity phenotypes of a mutant cis (CO2-insensitive) were caused by a deletion of MPK12. Lack of MPK12 impaired bicarbonate-induced activation of S-type anion channels. We demonstrated that MPK12 interacted with the protein kinase HIGH LEAF TEMPERATURE 1 (HT1)-a central node in guard cell CO2 signaling-and that MPK12 functions as an inhibitor of HT1. These data provide a new function for plant MPKs as protein kinase inhibitors and suggest a mechanism through which guard cell CO2 signaling controls plant water management.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Dióxido de Carbono/metabolismo , Variação Genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Mapeamento Cromossômico , Ozônio/metabolismo , Fotossíntese , Locos de Características Quantitativas , Água
15.
Molecules ; 24(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30986947

RESUMO

Due to the lack of approved vaccines against human leishmaniasis and the limitations of the current chemotherapy inducing side effects and drug resistance, development of new, effective chemotherapeutic agents is essential. This study describes the synthesis of a series of novel oxadiazoles and indolizine-containing compounds. The compounds were screened in silico using an EIIP/AQVN filter followed by ligand-based virtual screening and molecular docking to parasite arginase. Top hits were further screened versus human arginase and finally against an anti-target battery to tag their possible interactions with proteins essential for the metabolism and clearance of many substances. Eight candidate compounds were selected for further experimental testing. The results show measurable in vitro anti-leishmanial activity for three compounds. One compound with an IC50 value of 2.18 µM on Leishmania donovani intramacrophage amastigotes is clearly better positioned than the others as an interesting molecular template for further development of new anti-leishmanial agents.


Assuntos
Antiprotozoários/farmacologia , Indolizinas/farmacologia , Leishmania donovani/efeitos dos fármacos , Oxidiazóis/farmacologia , Animais , Antiprotozoários/química , Arginase/metabolismo , Indolizinas/química , Leishmania donovani/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxidiazóis/química , Células RAW 264.7
17.
J Comput Aided Mol Des ; 32(1): 211-224, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28879536

RESUMO

We have studied the binding of 102 ligands to the farnesoid X receptor within the D3R Grand Challenge 2016 blind-prediction competition. First, we employed docking with five different docking software and scoring functions. The selected docked poses gave an average root-mean-squared deviation of 4.2 Å. Consensus scoring gave decent results with a Kendall's τ of 0.26 ± 0.06 and a Spearman's ρ of 0.41 ± 0.08. For a subset of 33 ligands, we calculated relative binding free energies with free-energy perturbation. Five transformations between the ligands involved a change of the net charge and we implemented and benchmarked a semi-analytic correction (Rocklin et al., J Chem Phys 139:184103, 2013) for artifacts caused by the periodic boundary conditions and Ewald summation. The results gave a mean absolute deviation of 7.5 kJ/mol compared to the experimental estimates and a correlation coefficient of R 2 = 0.1. These results were among the four best in this competition out of 22 submissions. The charge corrections were significant (7-8 kJ/mol) and always improved the results. By employing 23 intermediate states in the free-energy perturbation, there was a proper overlap between all states and the precision was 0.1-0.7 kJ/mol. However, thermodynamic cycles indicate that the sampling was insufficient in some of the perturbations.


Assuntos
Simulação de Acoplamento Molecular , Receptores Citoplasmáticos e Nucleares/metabolismo , Termodinâmica , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Descoberta de Drogas , Humanos , Ligantes , Ligação Proteica , Conformação Proteica , Receptores Citoplasmáticos e Nucleares/química , Software
18.
Molecules ; 23(6)2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29890626

RESUMO

Pseudomonas aeruginosa is one of the most dreaded human pathogens, because of its intrinsic resistance to a number of commonly used antibiotics and ability to form sessile communities (biofilms). Innovative treatment strategies are required and that can rely on the attenuation of the pathogenicity and virulence traits. The interruption of the mechanisms of intercellular communication in bacteria (quorum sensing) is one of such promising strategies. A cobalt coordination compound (Co(HL)2) synthesized from (E)-2-(2-(pyridin-2-ylmethylene)hydrazinyl)-4-(p-tolyl)thiazole (HL) is reported herein for the first time to inhibit P. aeruginosa 3-oxo-C12-HSL-dependent QS system (LasI/LasR system) and underling phenotypes (biofilm formation and virulence factors). Its interactions with a possible target, the transcriptional activator protein complex LasR-3-oxo-C12-HSL, was studied by molecular modeling with the coordination compound ligand having stronger predicted interactions than those of co-crystallized ligand 3-oxo-C12-HSL, as well as known-binder furvina. Transition metal group 9 coordination compounds may be explored in antipathogenic/antibacterial drug design.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cobalto/química , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum , Tiazóis/farmacologia , Antibacterianos/química , Ligantes , Luminescência , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Oligopeptídeos/biossíntese , Pseudomonas aeruginosa/patogenicidade , Pseudomonas aeruginosa/fisiologia , Piocianina/biossíntese , Tiazóis/química
19.
Lancet ; 385(9982): 2067-76, 2015 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-25765696

RESUMO

BACKGROUND: The EXAMINE trial showed non-inferiority of the DPP-4 inhibitor alogliptin to placebo on major adverse cardiac event (MACE) rates in patients with type 2 diabetes and recent acute coronary syndromes. Concerns about excessive rates of in-hospital heart failure in another DPP-4 inhibitor trial have been reported. We therefore assessed hospital admission for heart failure in the EXAMINE trial. METHODS: Patients with type 2 diabetes and an acute coronary syndrome event in the previous 15-90 days were randomly assigned alogliptin or placebo plus standard treatment for diabetes and cardiovascular disease prevention. The prespecified exploratory extended MACE endpoint was all-cause mortality, non-fatal myocardial infarction, non-fatal stroke, urgent revascularisation due to unstable angina, and hospital admission for heart failure. The post-hoc analyses were of cardiovascular death and hospital admission for heart failure, assessed by history of heart failure and brain natriuretic peptide (BNP) concentration at baseline. We also assessed changes in N-terminal pro-BNP (NT-pro-BNP) from baseline to 6 months. This study is registered with ClinicalTrials.gov, number NCT00968708. FINDINGS: 5380 patients were assigned to alogliptin (n=2701) or placebo (n=2679) and followed up for a median of 533 days (IQR 280-751). The exploratory extended MACE endpoint was seen in 433 (16·0%) patients assigned to alogliptin and in 441 (16·5%) assigned to placebo (hazard ratio [HR] 0·98, 95% CI 0·86-1·12). Hospital admission for heart failure was the first event in 85 (3·1%) patients taking alogliptin compared with 79 (2·9%) taking placebo (HR 1·07, 95% CI 0·79-1·46). Alogliptin had no effect on composite events of cardiovascular death and hospital admission for heart failure in the post hoc analysis (HR 1·00, 95% CI 0·82-1·21) and results did not differ by baseline BNP concentration. NT-pro-BNP concentrations decreased significantly and similarly in the two groups. INTERPRETATION: In patients with type 2 diabetes and recent acute coronary syndromes, alogliptin did not increase the risk of heart failure outcomes. FUNDING: Takeda Development Center Americas.


Assuntos
Síndrome Coronariana Aguda/prevenção & controle , Diabetes Mellitus Tipo 2/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Insuficiência Cardíaca/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Piperidinas/efeitos adversos , Uracila/análogos & derivados , Idoso , Angina Instável/etiologia , Método Duplo-Cego , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Fatores de Risco , Acidente Vascular Cerebral/induzido quimicamente , Uracila/efeitos adversos
20.
N Engl J Med ; 369(14): 1327-35, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23992602

RESUMO

BACKGROUND: To assess potentially elevated cardiovascular risk related to new antihyperglycemic drugs in patients with type 2 diabetes, regulatory agencies require a comprehensive evaluation of the cardiovascular safety profile of new antidiabetic therapies. We assessed cardiovascular outcomes with alogliptin, a new inhibitor of dipeptidyl peptidase 4 (DPP-4), as compared with placebo in patients with type 2 diabetes who had had a recent acute coronary syndrome. METHODS: We randomly assigned patients with type 2 diabetes and either an acute myocardial infarction or unstable angina requiring hospitalization within the previous 15 to 90 days to receive alogliptin or placebo in addition to existing antihyperglycemic and cardiovascular drug therapy. The study design was a double-blind, noninferiority trial with a prespecified noninferiority margin of 1.3 for the hazard ratio for the primary end point of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. RESULTS: A total of 5380 patients underwent randomization and were followed for up to 40 months (median, 18 months). A primary end-point event occurred in 305 patients assigned to alogliptin (11.3%) and in 316 patients assigned to placebo (11.8%) (hazard ratio, 0.96; upper boundary of the one-sided repeated confidence interval, 1.16; P<0.001 for noninferiority). Glycated hemoglobin levels were significantly lower with alogliptin than with placebo (mean difference, -0.36 percentage points; P<0.001). Incidences of hypoglycemia, cancer, pancreatitis, and initiation of dialysis were similar with alogliptin and placebo. CONCLUSIONS: Among patients with type 2 diabetes who had had a recent acute coronary syndrome, the rates of major adverse cardiovascular events were not increased with the DPP-4 inhibitor alogliptin as compared with placebo. (Funded by Takeda Development Center Americas; EXAMINE ClinicalTrials.gov number, NCT00968708.).


Assuntos
Angina Instável/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Hipoglicemiantes/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Piperidinas/uso terapêutico , Uracila/análogos & derivados , Idoso , Angina Instável/complicações , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 2/complicações , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Piperidinas/efeitos adversos , Uracila/efeitos adversos , Uracila/uso terapêutico
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