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1.
Medicina (Kaunas) ; 55(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366186

RESUMO

Background and objectives: Medical devices such as catheters are used on a large scale to treat heart and cardiovascular diseases. Unfortunately, they present some important drawbacks (structure failure, calcifications, infections, thrombosis, etc.), with the main side effects occurring due to adhesion and proliferation of bacteria and living cells on the surface of the implanted devices. The aim of this work is to modify the surface of polyvinyl chloride (PVC), an affordable biocompatible material, in order to reduce these aforementioned side effects. Materials and Methods: The surface of PVC was modified by depositing a thin layer also of PVC that incorporates an active substance, dicoumarol (a well-known anticoagulant), by spin coating process. The modified surfaces were analyzed by Fourier-transform infrared (FT-IR) microscopy, Fourier-transform infrared (FT-IR) spectroscopy, Ultraviolet-visible spectroscopy (UV-VIS), and Scanning electron microscopy (SEM) in order to determine the surface morphology and behavior. The samples were tested for Gram-positive (S. aureus ATCC 25923) and Gram-negative (P. aeruginosa ATCC 27853) standard strains from American Type Culture Collection (ATCC). Results: The material obtained had a smooth surface with a uniform distribution of dicoumarol, which is released depending on the deposition parameters. The concentration of dicoumarol at the surface of the material and also the release rate is important for the applications for which the surface modification was designed. PVC modified using the proposed method showed a good ability to prevent salt deposition and decreased the protein adhesion, and the resistance to bacterial adherence was improved compared with standard PVC.


Assuntos
Dicumarol/uso terapêutico , Cloreto de Polivinila/efeitos adversos , Materiais Biocompatíveis , Cateteres/efeitos adversos , Cateteres/microbiologia , Cateteres/normas , Dicumarol/normas , Desenho de Equipamento/métodos , Desenho de Equipamento/normas , Humanos , Cloreto de Polivinila/normas , Cloreto de Polivinila/uso terapêutico
2.
Bioorg Med Chem Lett ; 29(10): 1236-1240, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30898405

RESUMO

Lipase RMIM was firstly used as a promiscuous biocatalyst to catalyze the Knoevenagel-Michael cascade reactions of 4-hydroxycoumarin with aromatic, heterocyclic or aliphatic aldehydes to synthesize dicoumarol derivatives in water. Results showed that the adopted methodology could offer many advantages, such as mild reaction conditions, pure aqueous reaction system, wide substrate applicability, recyclable catalyst, excellent yields (81-98%), operational simplicity, and environmentally friendly reactions.


Assuntos
Dicumarol/síntese química , Lipase/química , Rhizomucor/enzimologia , Aldeídos/química , Catálise , Dicumarol/análogos & derivados , Química Verde/métodos , Estrutura Molecular , Temperatura , Fatores de Tempo , Água/química
3.
Chem Commun (Camb) ; 55(27): 3951-3954, 2019 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-30874262

RESUMO

A far-red fluorescent probe has been developed for sensing fungal laccase. The probe was used to determine that Rhizopus oryzae had a high level endogenous laccase amongst 24 fungal strains. The Rhizopus oryzae was then used as a biocatalyst for the preparation of dicoumarin resulting in significant inhibition of Mycobacterium tuberculosis H37Ra.


Assuntos
Antituberculosos/farmacologia , Biocatálise , Dicumarol/farmacologia , Corantes Fluorescentes/química , Lacase/análise , Lacase/metabolismo , Mycobacterium tuberculosis/efeitos dos fármacos , Rhizopus/enzimologia , Antituberculosos/química , Antituberculosos/metabolismo , Dicumarol/química , Dicumarol/metabolismo , Testes de Sensibilidade Microbiana , Microscopia Confocal , Estrutura Molecular , Imagem Óptica
4.
PLoS One ; 14(2): e0212233, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30779774

RESUMO

Currently, there is no available therapy to eradicate hepatitis B virus (HBV) in chronically infected individuals. This is due to the difficulty in eliminating viral covalently closed circular (ccc) DNA, which is central to the gene expression and replication of HBV. We developed an assay system for nuclear circular DNA using an integration-deficient lentiviral vector. This vector produced non-integrated circular DNA in nuclei of infected cells. We engineered this vector to encode firefly luciferase to monitor the lentiviral episome DNA. We screened 3,840 chemicals by this assay for luciferase-reducing activity and identified dicumarol, which is known to have anticoagulation activity. We confirmed that dicumarol reduced lentiviral episome DNA. Furthermore, dicumarol inhibited HBV replication in cell culture using NTCP-expressing HepG2 and primary human hepatocytes. Dicumarol reduced intracellular HBV RNA, DNA, supernatant HBV antigens and DNA. We also found that dicumarol reduced the cccDNA level in HBV infected cells, but did not affect HBV adsorption/entry. This is a novel assay system for screening inhibitors targeting nuclear cccDNA and is useful for finding new antiviral substances for HBV.


Assuntos
Antivirais/farmacologia , Núcleo Celular/metabolismo , DNA Viral/metabolismo , Dicumarol/farmacologia , Vírus da Hepatite B/metabolismo , Plasmídeos/metabolismo , Núcleo Celular/genética , Núcleo Celular/virologia , DNA Viral/genética , Avaliação Pré-Clínica de Medicamentos , Vetores Genéticos , Células HEK293 , Células Hep G2 , Vírus da Hepatite B/genética , Humanos , Lentivirus , Plasmídeos/genética , RNA Viral/genética , RNA Viral/metabolismo
5.
Neurochem Res ; 44(2): 333-346, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30443714

RESUMO

Dicoumarol is frequently used as inhibitor of the detoxifying enzyme NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1). In order to test whether dicoumarol may also affect the cellular glutathione (GSH) metabolism, we have exposed cultured primary astrocytes to dicoumarol and investigated potential effects of this compound on the cell viability as well as on the cellular and extracellular contents of GSH and its metabolites. Incubation of astrocytes with dicoumarol in concentrations of up to 100 µM did not acutely compromise cell viability nor was any GSH consumption or GSH oxidation to glutathione disulfide (GSSG) observed. However, unexpectedly dicoumarol inhibited the cellular multidrug resistance protein (Mrp) 1-dependent export of GSH in a time- and concentration-dependent manner with half-maximal effects observed at low micromolar concentrations of dicoumarol. Inhibition of GSH export by dicoumarol was not additive to that observed for the known Mrp1 inhibitor MK571. In addition, dicoumarol inhibited also the Mrp1-mediated export of GSSG during menadione-induced oxidative stress and the export of the GSH-bimane-conjugate (GS-B) that had been generated in the cells after exposure to monochlorobimane. Half-maximal inhibition of the export of Mrp1 substrates was observed at dicoumarol concentrations of around 4 µM (GSH and GSSG) and 30 µM (GS-B). These data demonstrate that dicoumarol strongly affects the GSH metabolism of viable cultured astrocytes by inhibiting Mrp1-mediated export processes and identifies for the first time Mrp1 as additional cellular target of dicoumarol.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dicumarol/farmacologia , Propionatos/farmacologia , Quinolinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Células Cultivadas , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Ratos Wistar
6.
Biosci Rep ; 39(1)2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30518535

RESUMO

NAD(P)H quinone oxidoreductase 1 (NQO1) catalyses the two electron reduction of quinones and a wide range of other organic compounds. Its physiological role is believed to be partly the reduction of free radical load in cells and the detoxification of xenobiotics. It also has non-enzymatic functions stabilising a number of cellular regulators including p53. Functionally, NQO1 is a homodimer with two active sites formed from residues from both polypeptide chains. Catalysis proceeds via a substituted enzyme mechanism involving a tightly bound FAD cofactor. Dicoumarol and some structurally related compounds act as competitive inhibitors of NQO1. There is some evidence for negative cooperativity in quinine oxidoreductases which is most likely to be mediated at least in part by alterations to the mobility of the protein. Human NQO1 is implicated in cancer. It is often over-expressed in cancer cells and as such is considered as a possible drug target. Interestingly, a common polymorphic form of human NQO1, p.P187S, is associated with an increased risk of several forms of cancer. This variant has much lower activity than the wild-type, primarily due to its substantially reduced affinity for FAD which results from lower stability. This lower stability results from inappropriate mobility of key parts of the protein. Thus, NQO1 relies on correct mobility for normal function, but inappropriate mobility results in dysfunction and may cause disease.


Assuntos
Dicumarol/química , Inibidores Enzimáticos/química , Flavina-Adenina Dinucleotídeo/química , NAD(P)H Desidrogenase (Quinona)/química , Neoplasias/enzimologia , Domínio Catalítico , Dicumarol/farmacologia , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Flavina-Adenina Dinucleotídeo/metabolismo , Expressão Gênica , Humanos , Modelos Moleculares , Mutação , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica
7.
Bioorg Chem ; 80: 741-752, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30077781

RESUMO

Dicoumarol derivatives were synthesized in the InCl3 catalyzed pseudo three-component reactions of 4-hydroxycoumarin with aromatic aldehydes in excellent yields. The reactions were performed in water under microwave irradiation. All synthesized compounds were characterized using NMR, IR, and UV-Vis spectroscopy, as well as with TD-DFT. Obtained dicoumarols were subjected to evaluation of their in vitro lipid peroxidation and soybean lipoxygenase inhibition activities. It was shown that five of ten examined compounds (3e, 3h, 3b, 3d, 3f) possess significant potential of antilipid peroxidation (84-97%), and that compounds 3b, 3e, 3h provided the highest soybean lipoxygenase (LOX-Ib) inhibition (IC50 = 52.5 µM) and 3i somewhat lower activity (IC50 = 55.5 µM). The bioactive conformations of the best LOX-Ib inhibitors were obtained by means of molecular docking and molecular dynamics. It was shown that, within the bioactive conformations interior to LOX-Ib active site, the most active compounds form the pyramidal structure made of two 4-hydroxycoumarin cores and a central phenyl substituent. This form serves as a spatial barrier which prevents LOX-Ib Fe2+/Fe3+ ion activity to generate the coordinative bond with the C13 hydroxyl group of the α-linoleate. It is worth pointing out that the most active compounds 3b, 3e, 3h and 3i can be candidates for further examination of their in vitro and in vivo anti-inflammatory activity and that molecular modeling study results provide possibility to screen bioactive conformations and elucidate the mechanism of dicoumarols anti-LOX activity.


Assuntos
Dicumarol/análogos & derivados , Dicumarol/farmacologia , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Dicumarol/síntese química , Desenho de Fármacos , Química Verde , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/síntese química , Simulação de Acoplamento Molecular , Soja/enzimologia , Relação Estrutura-Atividade
8.
J Am Med Dir Assoc ; 19(11): 936-941, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891182

RESUMO

OBJECTIVE: The safety of direct oral anticoagulants (DOACs) in oldest old patients with nonvalvular atrial fibrillation (NVAF) in daily clinical practice has not been systematically assessed. This study examined the safety of DOACs and dicumarol (a vitamin K antagonist) in NVAF geriatric patients. DESIGN: Prospective study from January 2010 through June 2015, with follow-up through January 2016. SETTING: Geriatric medicine department at a tertiary hospital. PARTICIPANTS: A total of 554 outpatients, 75 years or older, diagnosed of NVAF and starting oral anticoagulation. MEASUREMENTS: The main outcome was bleeding, which was classified into major (including those life-threatening) and nonmajor episodes. Statistical analyses were performed with Cox regression. RESULTS: A total of 351 patients received DOACs and 193 dicumarol. Patients on DOACs were older, with more frequent comorbidities, mobility limitation and disability in activities of daily living, as well as higher mortality, than those treated with dicumarol. The incidence of any bleeding was 19.2/100 person-years among patients on DOACs and 13.7/100 person-years on dicumarol; corresponding figures for major bleeding were 5.2 for those on DOACs, and 3.3 for those on dicumarol. In crude analyses, hazard ratios (95% confidence intervals) for any bleeding, and for mayor bleeding in patients on DOACs vs dicumarol were 1.60 (1.04-2.44) and 2.22 (0.88-5.59), respectively. Excess risk of bleeding associated with DOACs vs dicumarol disappeared after adjustment for clinical characteristics, so that corresponding figures were 1.19 (0.68-2.08) and 1.01 (0.35-2.93). Results did not vary across subgroups of high-risk patients. CONCLUSION: In very old patients with NVAF, the higher risk of bleeding associated with DOACs vs dicumarol could be mostly explained by the worse clinical profile of patients receiving DOACs. Risk of bleeding was rather high, and warrants close clinical monitoring.


Assuntos
Anticoagulantes/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Dicumarol/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Administração Oral , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Doença Crônica/epidemiologia , Comorbidade , Dabigatrana/administração & dosagem , Dabigatrana/efeitos adversos , Demência/epidemiologia , Dicumarol/administração & dosagem , Pessoas com Deficiência , Seguimentos , Humanos , Limitação da Mobilidade , Estudos Prospectivos , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Rivaroxabana/administração & dosagem , Rivaroxabana/efeitos adversos , Vitamina K/antagonistas & inibidores
9.
J Chromatogr A ; 1539: 93-102, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29395163

RESUMO

In this work, a method for the extraction of dicoumarol from plant sample utilizing selective adsorbent based on molecularly imprinted polymer was developed. Molecularly imprinted polymer (MIP) was synthesized by bulk polymerization, and on the surface of magnetic particles using dicoumarol as a template, methacrylic acid as functional monomer, chloroform as a porogen, and ethyleneglycol dimethacrylate as a cross-linker. Prepared polymeric materials were evaluated on the base of capacity, selectivity, and morphology. The maximal specific adsoption capacities of the sorbents were 45 µg (for bulk MIP) and 36 µg (for MIP on the magnetic particles) of dicoumarol per 1 g of polymer. An efficiencies of sorption processes of dicoumarol on prepared sorbents were evaluated under various conditions (type of sample solvent, pH, types of washing and elution solvents). The MIP based sorbents were used for solid phase extraction of dicoumarol. Applicability of MIP-SPE coupled to HPLC-DAD was tested for the selective extraction of dicoumarol from sample of sweet clover. The method was linear over concentration range from 1 to 100 µg mL-1 (the correlation coefficient 0.9984) with limit of detection 0.2 µg mL-1. Accuracy of the method was assessed for spiked sample at three concentration levels and recovery values were higher than 84% with relative standard deviation lower than 3.2%.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Dicumarol/análise , Melilotus/química , Extração em Fase Sólida , Impressão Molecular , Polímeros/química , Solventes/química
10.
J Biochem ; 163(4): 329-339, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29319808

RESUMO

Coenzyme Q (CoQ) is an essential factor of the mitochondrial respiratory chain. CoQ homologues with different lengths of the isoprenoid side chain are widely distributed in nature, but little is known about the relationship between the isoprenoid side chain length and biological function; therefore, we examined the effects of CoQ homologues on HeLa cells. When CoQ homologues with a shorter isoprenoid side chain than CoQ4 were added to HeLa cells, they induced cell death, and the order of cytotoxic intensity was as follows: CoQ0 ≫ CoQ3 ≈ CoQ1 > CoQ2 ≫ CoQ4. Furthermore, we found that CoQ1, CoQ2 and CoQ3 could induce caspase-mediated apoptosis, and the order of intensity was as follows: CoQ3 > CoQ2 ≥ CoQ1. We could not identify the participation of reactive oxygen species in the apoptosis induction, but observed that an NAD(P)H dehydrogenase (quinone) 1 (NQO1) inhibitor, dicumarol, could inhibit not only the intracellular reduction of the homologues but also apoptosis. However, because dicumarol did not affect well-known apoptosis inducers, such as anti-Fas IgG, tumor necrosis factor (TNF)-α, TNF-related apoptosis-inducing ligand, UV-B and H2O2 of HeLa cells at all, we concluded that NQO1-related intracellular reduction of CoQ, or its reduced product, ubiquinol, may participate in the apoptosis induction of HeLa cells.


Assuntos
Apoptose/efeitos dos fármacos , Terpenos/farmacologia , Ubiquinona/metabolismo , Dicumarol/farmacologia , Células HeLa , Humanos , Oxirredução , Terpenos/química , Terpenos/metabolismo , Ubiquinona/antagonistas & inibidores
11.
JCI Insight ; 2(22)2017 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-29202460

RESUMO

Environmental exposures pose a significant threat to human health. However, it is often difficult to study toxicological mechanisms in human subjects due to ethical concerns. Plant-derived aristolochic acids are among the most potent nephrotoxins and carcinogens discovered to date, yet the mechanism of bioactivation in humans remains poorly understood. Microphysiological systems (organs-on-chips) provide an approach to examining the complex, species-specific toxicological effects of pharmaceutical and environmental chemicals using human cells. We microfluidically linked a kidney-on-a-chip with a liver-on-a-chip to determine the mechanisms of bioactivation and transport of aristolochic acid I (AA-I), an established nephrotoxin and human carcinogen. We demonstrate that human hepatocyte-specific metabolism of AA-I substantially increases its cytotoxicity toward human kidney proximal tubular epithelial cells, including formation of aristolactam adducts and release of kidney injury biomarkers. Hepatic biotransformation of AA-I to a nephrotoxic metabolite involves nitroreduction, followed by sulfate conjugation. Here, we identify, in a human tissue-based system, that the sulfate conjugate of the hepatic NQO1-generated aristolactam product of AA-I (AL-I-NOSO3) is the nephrotoxic form of AA-I. This conjugate can be transported out of liver via MRP membrane transporters and then actively transported into kidney tissue via one or more organic anionic membrane transporters. This integrated microphysiological system provides an ex vivo approach for investigating organ-organ interactions, whereby the metabolism of a drug or other xenobiotic by one tissue may influence its toxicity toward another, and represents an experimental approach for studying chemical toxicity related to environmental and other toxic exposures.


Assuntos
Ácidos Aristolóquicos/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Animais , Biomarcadores , Biotransformação , Carcinógenos/toxicidade , Dicumarol/metabolismo , Células Epiteliais , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Rim/lesões , Masculino , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Néfrons/efeitos dos fármacos , Néfrons/metabolismo , Patologia Molecular/instrumentação , Patologia Molecular/métodos , Ratos , Ratos Sprague-Dawley , Insuficiência Renal Crônica , Xenobióticos
12.
Future Med Chem ; 9(14): 1597-1609, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28891315

RESUMO

AIM: A structural study of a series of pyridine dicoumarol derivatives with potential activity against a novel Topoisomerase IIß kinase which was identified in the HIV-1 viral lysate, compounds were designed and synthesized based on a 3D-QSAR study. MATERIALS & METHODS: Based on QSAR model we have designed and synthesized a series of pyridine dicoumarol derivatives and characterized by spectral studies, all the molecules are biologically evaluated by kinase assay, cytotoxicity assay, ELISA and PCR method. RESULT: We demonstrated the achievement of water soluble disodium pyridine dicoumarate derivatives showing high anti-HIV-1 activity (IC50 <25 nM) which provides a crucial point for further development of pyridine dicoumarol series as HIV-1-associated topoisomerase IIß kinase inhibitors for clinical application against AIDS. CONCLUSION: A new class of anti-HIV-1 lead compounds have been designed and tested. Further studies would result in development of  novel and potential drugs.


Assuntos
DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Dicumarol/metabolismo , HIV-1/enzimologia , Inibidores da Topoisomerase II/metabolismo , Fármacos Anti-HIV/química , Fármacos Anti-HIV/metabolismo , Fármacos Anti-HIV/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/antagonistas & inibidores , Dicumarol/química , Dicumarol/farmacologia , Desenho de Fármacos , Ensaio de Imunoadsorção Enzimática , Proteína do Núcleo p24 do HIV/antagonistas & inibidores , Proteína do Núcleo p24 do HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Piridinas/química , Relação Quantitativa Estrutura-Atividade , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-28807907

RESUMO

De novo pyrimidine biosynthesis is a key metabolic pathway involved in multiple biosynthetic processes. Here, we identified an original series of 3-(1H-indol-3-yl)-2,3-dihydro-4H-furo[3,2-c]chromen-4-one derivatives as a new class of pyrimidine biosynthesis inhibitors formed by two edge-fused polycyclic moieties. We show that identified compounds exhibit broad-spectrum antiviral activity and immunostimulatory properties, in line with recent reports linking de novo pyrimidine biosynthesis with innate defense mechanisms against viruses. Most importantly, we establish that pyrimidine deprivation can amplify the production of both type I and type III interferons by cells stimulated with retinoic acid-inducible gene 1 (RIG-I) ligands. Altogether, our results further expand the current panel of pyrimidine biosynthesis inhibitors and illustrate how the production of antiviral interferons is tightly coupled to this metabolic pathway. Functional and structural similarities between this new chemical series and dicoumarol, which was reported before to inhibit pyrimidine biosynthesis at the dihydroorotate dehydrogenase (DHODH) step, are discussed.


Assuntos
Antivirais/farmacologia , Vírus Chikungunya/imunologia , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Interferon Tipo I/biossíntese , Interferons/biossíntese , Vírus do Sarampo/imunologia , Pirimidinas/biossíntese , Antivirais/química , Linhagem Celular , Cromonas/química , Dicumarol/farmacologia , Inibidores Enzimáticos/química , Células HEK293 , Humanos , Imunidade Inata/imunologia , Indóis/química , Interferon Tipo I/imunologia , Interferons/imunologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Relação Estrutura-Atividade
14.
PLoS One ; 12(6): e0179672, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28617852

RESUMO

Pyruvate dehydrogenase kinase 1 (PDK1) is overexpressed in ovarian cancer and thus is a promising anticancer therapeutic target. Our previous work suggests that coumarin compounds are potential inhibitors of PDKs. In this study, we used the ovarian cancer cell line SKOV3 as the model system and examined whether dicumarol (DIC), a coumarin compound, could inhibit ovarian cancer through targeting PDK1. We showed that DIC potently inhibited the kinase activity of PDK1, shifted the glucose metabolism from aerobic glycolysis to oxidative phosphorylation, generated a higher level of reactive oxygen species (ROS), attenuated the mitochondrial membrane potential (MMP), induced apoptosis, and reduced cell viability in vitro. The same phenotypes induced by DIC also were translated in vivo, leading to significant suppression of xenograft growth. This study not only identifies a novel inhibitor for PDK1, but it also reveals novel anticancer mechanisms of DIC and provides a promising anticancer therapy that targets the Warburg effect.


Assuntos
Dicumarol/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias Ovarianas/enzimologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Quinase Piruvato Desidrogenase (Transferência de Acetil) , Espécies Reativas de Oxigênio/metabolismo
15.
Oncotarget ; 8(12): 20309-20327, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28411284

RESUMO

Here, we identified two new molecular targets, which are functionally sufficient to metabolically confer the tamoxifen-resistance phenotype in human breast cancer cells. Briefly, ~20 proteins were first selected as potential candidates, based on unbiased proteomics analysis, using tamoxifen-resistant cell lines. Then, the cDNAs of the most promising candidates were systematically transduced into MCF-7 cells. Remarkably, NQO1 and GCLC were both functionally sufficient to autonomously confer a tamoxifen-resistant metabolic phenotype, characterized by i) increased mitochondrial biogenesis, ii) increased ATP production and iii) reduced glutathione levels. Thus, we speculate that pharmacological inhibition of NQO1 and GCLC may be new therapeutic strategies for overcoming tamoxifen-resistance in breast cancer patients. In direct support of this notion, we demonstrate that treatment with a known NQO1 inhibitor (dicoumarol) is indeed sufficient to revert the tamoxifen-resistance phenotype. As such, these findings could have important translational significance for the prevention of tumor recurrence in ER(+) breast cancers, which is due to an endocrine resistance phenotype. Importantly, we also show here that NQO1 has significant prognostic value as a biomarker for the prediction of tumor recurrence. More specifically, higher levels of NQO1 mRNA strongly predict patient relapse in high-risk ER(+) breast cancer patients receiving endocrine therapy (mostly tamoxifen; H.R. > 2.15; p = 0.007).


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Glutamato-Cisteína Ligase/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Tamoxifeno/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dicumarol/farmacologia , Inibidores Enzimáticos/farmacologia , Feminino , Glutamato-Cisteína Ligase/genética , Humanos , Células MCF-7 , Mitocôndrias/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , Recidiva Local de Neoplasia/genética , Prognóstico , Proteômica/métodos , RNA Mensageiro/genética
16.
Neurotox Res ; 32(1): 134-140, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28285345

RESUMO

Dopamine oxidation in the pathway leading to neuromelanin formation generates the ortho-quinone aminochrome, which is potentially neurotoxic but normally rapidly converted by DT-diaphorase to nontoxic leukoaminochrome. However, when administered exogenously into rat striatum, aminochrome is able to produce damage to dopaminergic neurons. Because of a recent report that substantia nigra pars compacta (SNpc) tyrosine hydroxylase (T-OH) levels were unaltered by aminochrome when there was cell shrinkage of dopaminergic neurons along with a reduction in striatal dopamine release, the following study was conducted to more accurately determine the role of DT-diaphorase in aminochrome neurotoxicity. In this study, a low dose of aminochrome (0.8 nmol) with or without the DT-diaphorase inhibitor dicoumarol (0.2 nmol) was injected into the left striatum of rats. Intrastriatal 6-hydroxydopamine (6-OHDA, 32 nmol) was used as a positive neurotoxin control in other rats. Two weeks later, there was significant loss in numbers of T-OH immunoreactive fibers in SNpc, also a loss in cell density in SNpc, and prominent apomorphine (0.5 mg/kg sc)-induced contralateral rotations in rats that had been treated with aminochrome, with aminochrome/dicoumarol, or with 6-OHDA. Findings demonstrate that neurotoxic aminochrome is able to exert neurotoxicity only when DT-diaphorase is suppressed-implying that DT-diaphorase is vital in normally suppressing toxicity of in vivo aminochrome, generated in the pathway towards neuromelanin formation.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Indolquinonas/toxicidade , NAD(P)H Desidrogenase (Quinona)/metabolismo , Síndromes Neurotóxicas/etiologia , Neurotoxinas/toxicidade , Animais , Dicumarol/farmacologia , Modelos Animais de Doenças , Masculino , Oxirredução/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Tirosina 3-Mono-Oxigenase/metabolismo
17.
Med Oral Patol Oral Cir Bucal ; 22(2): e258-e263, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28160591

RESUMO

BACKGROUND: The aim is to evaluate periodontal alteration and biochemical markers associated with bone turnover in chronic oral with dicoumarins anticoagulant treatment patients. MATERIAL AND METHODS: 80 patients treated with oral anticoagulants were divided into 2 cohort: Group A (n=36) 6 month to 1 year with anticoagulant treatment and Group B (n=44) > 2 years with anticoagulant treatment. Clinical evaluation included: Clinical attachment level (CAL), plaque index (PI) and gingival index (GI). Analytically biochemical parameters of bone remodeling (calcium and phosphorus), formation (total acid phosphatase, alkaline phosphatase and osteocalcin) and resorption (tartrate-resistant acid phosphatase and beta-crosslaps) were evaluated. RESULTS: High values of PI (67-100%) especially in men and in Group B were observed. Men with anticoagulation treatment length showed an increased GI (49.167 vs 78.083) while Group B women showed a decreased GI in comparison with Group A (59.389 vs 42.120). Women presented a greater average CAL than men as well as Group B vs Group A but without statistical significance. All biochemical markers were decreased respect to values of general population. Osteocalcin in GroupB women showed a statistically significant outcome vs GroupA (p=0.004). Acid phosphatase (total and tartrate-resistant) has a slight increase in Group B women versus Group A, and Beta-crosslap showed lower values in Group A men than Group B and slightly lower in Group A women versus Group B, without statistical significance. CONCLUSIONS: Patients showed a slight to moderate degree of periodontal affectation, especially gingivitis related to bacterial plaque. Periodontal disorders tended to be more severe in Group B. While bone remodeling showed an overall decrease with greater affectation of bone neoformation phenomena, bone destruction tended to recover and normalize in time.


Assuntos
Anticoagulantes/administração & dosagem , Osso e Ossos/metabolismo , Dicumarol/administração & dosagem , Periodonto/metabolismo , Administração Oral , Idoso , Biomarcadores/análise , Feminino , Humanos , Masculino
18.
Bioorg Med Chem Lett ; 27(5): 1325-1328, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28159415

RESUMO

A series of novel ROS inducers were designed by merging the fragments of piperlongumine and dicoumarol. Most of these derivatives showed potent in vitro activity against three cancer cell lines and good selectivity towards normal lung cells. The most potent and selective compound 3e was proven to exhibit obvious ROS elevation and excellent in vivo antitumor activity with suppressed tumor growth by 48.46% at the dose of 5mg/kg. Supported by these investigation, these findings encourage further investigation around this interesting antitumor chemotype.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Dicumarol/química , Dioxolanos/química , Espécies Reativas de Oxigênio , Células A549 , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Dicumarol/síntese química , Dicumarol/farmacologia , Dioxolanos/síntese química , Dioxolanos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Xenoenxertos , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo
19.
Mol Pharm ; 14(3): 856-865, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28166408

RESUMO

A variety of particle sizes of a model compound, dicumarol, were prepared and characterized in order to investigate the correlation between particle size and solid-state NMR (SSNMR) proton spin-lattice relaxation (1H T1) times. Conventional laser diffraction and scanning electron microscopy were used as particle size measurement techniques and showed crystalline dicumarol samples with sizes ranging from tens of micrometers to a few micrometers. Dicumarol samples were prepared using both bottom-up and top-down particle size control approaches, via antisolvent microprecipitation and cryogrinding. It was observed that smaller particles of dicumarol generally had shorter 1H T1 times than larger ones. Additionally, cryomilled particles had the shortest 1H T1 times encountered (8 s). SSNMR 1H T1 times of all the samples were measured and showed as-received dicumarol to have a T1 of 1500 s, whereas the 1H T1 times of the precipitated samples ranged from 20 to 80 s, with no apparent change in the physical form of dicumarol. Physical mixtures of different sized particles were also analyzed to determine the effect of sample inhomogeneity on 1H T1 values. Mixtures of cryoground and as-received dicumarol were clearly inhomogeneous as they did not fit well to a one-component relaxation model, but could be fit much better to a two-component model with both fast-and slow-relaxing regimes. Results indicate that samples of crystalline dicumarol containing two significantly different particle size populations could be deconvoluted solely based on their differences in 1H T1 times. Relative populations of each particle size regime could also be approximated using two-component fitting models. Using NMR theory on spin diffusion as a reference, and taking into account the presence of crystal defects, a model for the correlation between the particle size of dicumarol and its 1H T1 time was proposed.


Assuntos
Dicumarol/química , Precipitação Química , Espectroscopia de Ressonância Magnética/métodos , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Prótons
20.
Biochem Biophys Res Commun ; 483(1): 680-686, 2017 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-27986568

RESUMO

Deoxynyboquinone (DNQ), a potent novel quinone-based antineoplastic agent, selectively kills solid cancers with overexpressed cytosolic NAD(P)H:quinone oxidoreductase-1 (NQO1) via excessive ROS production. A genetically encoded redox-sensitive probe was used to monitor intraorganellar glutathione redox potentials (EGSH) as a direct indicator of cellular oxidative stress following chemotherapeutic administration. Beta-lapachone (ß-lap) and DNQ-induced spatiotemporal redox responses were monitored in human lung A549 and pancreatic MIA-PaCa-2 adenocarcinoma cells incubated with or without dicumarol and ES936, potent NQO1 inhibitors. Immediate oxidation of EGSH in both the cytosol and mitochondrial matrix was observed in response to DNQ and ß-lap. The DNQ-induced cytosolic oxidation was fully prevented with NQO1 inhibition, whereas mitochondrial oxidation in A549 was NQO1-independent in contrast to MIA-PaCa-2 cells. However, at pharmacologic concentrations of ß-lap both quinone-based substrates directly oxidized the redox probe, a possible sign of off-target reactivity with cellular thiols. Together, these data provide new evidence that DNQ's direct and discerning NQO1 substrate specificity underlies its pharmacologic potency, while ß-lap elicits off-target responses at its effective doses.


Assuntos
Antineoplásicos/farmacologia , Glutationa/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Quinonas/farmacologia , Técnicas Biossensoriais , Linhagem Celular Tumoral , Citosol/efeitos dos fármacos , Citosol/metabolismo , Dicumarol/farmacologia , Corantes Fluorescentes/análise , Glutarredoxinas/análise , Glutarredoxinas/genética , Glutationa/análise , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Humanos , Indolquinonas/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Imagem Molecular , Sondas Moleculares/genética , Terapia de Alvo Molecular , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Naftoquinonas/metabolismo , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Especificidade por Substrato
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