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1.
J Agric Food Chem ; 67(36): 10018-10031, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31448918

RESUMO

Plant diseases seriously endanger plant health, and it is very difficult to control them. A series of nortopsentin analogues were designed, synthesized, and evaluated for their antiviral activities and fungicidal activities. Most of these compounds displayed higher antiviral activities than ribavirin. Compounds 1d, 1e, and 12a, with excellent antiviral activities, emerged as novel antiviral lead compounds, among which 1e was selected for further antiviral mechanism research. The mechanism research results indicated that these compounds may play an antiviral role by aggregating viral particles to prevent their movement in plants. Further fungicidal activity tests revealed that nortopsentin analogues displayed broad-spectrum fungicidal activities. Compounds 2p and 2f displayed higher antifungal activities against Alternaria solani than the commercial fungicides carbendazim and chlorothalonil. Current research has laid a foundation for the application of nortopsentin analogues in plant protection.


Assuntos
Antivirais/farmacologia , Fungicidas Industriais/farmacologia , Oxazóis/farmacologia , Tiazóis/farmacologia , Alternaria/efeitos dos fármacos , Alternaria/crescimento & desenvolvimento , Antivirais/síntese química , Antivirais/química , Desenho de Drogas , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Oxazóis/química , Relação Estrutura-Atividade , Tiazóis/química , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Vírus do Mosaico do Tabaco/crescimento & desenvolvimento
2.
Cancer Invest ; 37(7): 311-324, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31412710

RESUMO

Enthusiasms into the application of PI3K-δ inhibitor CAL-101 has been muted due to the over-activation of compensatory molecules. Our results delineated that c-Myc suppression using 10058-F4 enhanced CAL-101 cytotoxicity in less sensitive cells through different mechanisms based on p53 status; while CAL-101-plus-10058-F4 induced G1 arrest in wild-type p53-expressing leukemic cells, no conspicuous increase in G1 was noted in U937 cells harboring mutant p53. Conclusively, this study shed lights on the role of c-Myc oncoprotein in acute leukemia cells sensitivity to PI3K inhibitor and outlined that the combination of c-Myc inhibitor and CAL-101 may be a promising therapeutic approach in leukemia.


Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide Aguda/genética , Purinas/farmacologia , Quinazolinonas/farmacologia , Tiazóis/farmacologia , Proteína Supressora de Tumor p53/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo
3.
Life Sci ; 232: 116639, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295472

RESUMO

AIMS: Sirtuins have been implicated in the aging process, however, the functions of SIRT2 in post-maturation aging of oocytes are not fully understood. The purpose of the present investigation was to assess the roles of SIRT2 in aged oocytes and mechanisms involved. MAIN METHODS: The fresh MII oocytes were aging in vitro, and treated with SIRT2 inhibitor (SirReal2), autophagy activator (Rapamycin), and autophagy inhibitor (3-Ma) for 24 h, respectively. Oocyte activation, cytoplasmic fragmentation, and spindle defects, mitochondrial distribution, ROS levels, ATP production, mitochondrial membrane potential, and early apoptosis were investigated. Western blotting was performed to determine LC3-II accumulation, SQSTM1 degradation, and caspase-3 activity. KEY FINDINGS: SIRT2 expression gradually decreased in a time-dependent manner during oocyte aging. Treatment with SirReal2 significantly increased the rates of oocyte activation, cytoplasmic fragmentation, and spindle defects. In particular, the high ROS levels, abnormal mitochondrial distribution, low ATP production, and lost ΔΨm were observed in SirReal2-exposed oocytes. Further analysis revealed that LC3-II accumulation and SQSTM1 degradation were induced by SIRT2 inhibition. By performing early apoptosis analysis showed that oocyte aging was accompanied with cellular apoptosis, and SIRT2 inhibition increased apoptosis rates of aged oocytes. Importantly, upregulating autophagy with Rapamycin could mimic the effects of SIRT2 inhibition on apoptosis by increasing caspase-3 activation, whereas downregulating autophagy with 3-MA could abolish those effects by blocking caspase-3 activation. SIGNIFICANCE: Our results suggest that SIRT2 inactivation is a key mechanism underlying of cellular aging, and SIRT2 inhibition contributes to autophagy-dependent cellular apoptosis in post-maturation oocytes.


Assuntos
Oócitos/fisiologia , Sirtuína 2/fisiologia , Acetamidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Bovinos , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Oócitos/classificação , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Sirolimo/farmacologia , Sirtuína 2/antagonistas & inibidores , Sirtuína 2/metabolismo , Tiazóis/farmacologia
4.
Expert Rev Clin Pharmacol ; 12(9): 859-865, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31352834

RESUMO

Introduction: Thrombocytopenia is a common hematological abnormality in patients with chronic liver disease (CLD), occurring in 64%~84% of patients with cirrhosis or fibrosis. Due to the increased risk of bleeding, thrombocytopenia potentially affects management of CLD, such as surgery or liver biopsy. Avatrombopag is a new oral thrombopoietin (TPO) receptor agonist, activating TPO receptor and increasing megakaryocytic proliferation/differentiation and platelet production. Areas covered: This review summarizes the collected data concerning pharmacokinetics, clinical efficacy, safety and tolerability profiles of avatrombopag for the management of thrombocytopenia in patients with CLD. Expert opinion: Avatrombopag is recently approved by Food and Drug Administration (FDA) for the treatment of thrombocytopenia in patients with CLD who are scheduled to undergo a procedure. Based on the available clinical trials, avatrombopag is superior to placebo in reducing the need for platelet transfusions or rescue procedures for bleeding. Avatrombopag is also recommended as alternative to platelet transfusions.


Assuntos
Hepatopatias/complicações , Tiazóis/uso terapêutico , Tiofenos/uso terapêutico , Trombocitopenia/tratamento farmacológico , Doença Crônica , Hemorragia/etiologia , Hemorragia/prevenção & controle , Humanos , Cirrose Hepática/complicações , Hepatopatias/fisiopatologia , Transfusão de Plaquetas/métodos , Receptores de Trombopoetina/agonistas , Tiazóis/efeitos adversos , Tiazóis/farmacologia , Tiofenos/efeitos adversos , Tiofenos/farmacologia , Trombocitopenia/etiologia
5.
Anticancer Res ; 39(7): 3433-3442, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262867

RESUMO

BACKGROUND/AIM: DOG1 is a calcium-activated chloride channel that has gained attention as a promising drug target due to its involvement in several processes essential for tumor development and progression. DOG1 is overexpressed in >95% of gastrointestinal stromal tumors (GIST). The aim was to determine DOG1 inhibition antitumoral effects on GIST. MATERIALS AND METHODS: Human GIST (GIST-T1 and GIST882) cell lines were used to study the effect of DOG1 inhibitors on chloride currents, viability, colony formation, and cell cycle. RESULTS: CaCCinh-A01 decreased chloride currents. CaCCinh-A01 and T16inh-A01 reduced GIST cell viability and CaCCinh-A01 affected cell cycle distribution leading to G1 cell-cycle arrest. CaCCinh-A01 also increased the sub-G1 phase population, indicative of apoptosis, in GIST882. CaCCinh-A01 strongly reduced the colony forming ability of the cells, whereas T16inh-A01 did not. CONCLUSION: DOG1 inhibition has antitumoral effects in GIST cells in vitro, and could potentially serve as a target for GIST therapy.


Assuntos
Anoctamina-1/antagonistas & inibidores , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Anoctamina-1/fisiologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Gastrointestinais/fisiopatologia , Tumores do Estroma Gastrointestinal/fisiopatologia , Humanos , Proteínas de Neoplasias/fisiologia , Pirimidinas/farmacologia , Tiazóis/farmacologia , Tiofenos/farmacologia
6.
Gastroenterology ; 157(3): 793-806.e14, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31170413

RESUMO

BACKGROUND & AIMS: The role of aryl hydrocarbon receptor (AhR) in liver fibrosis is controversial because loss and gain of AhR activity both lead to liver fibrosis. The goal of this study was to investigate how the expression of AhR by different liver cell types, hepatic stellate cells (HSCs) in particular, affects liver fibrosis in mice. METHODS: We studied the effects of AhR on primary mouse and human HSCs, measuring their activation and stimulation of fibrogenesis using RNA-sequencing analysis. C57BL/6J mice were given the AhR agonists 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE); were given carbon tetrachloride (CCl4); or underwent bile duct ligation. We also performed studies in mice with disruption of Ahr specifically in HSCs, hepatocytes, or Kupffer cells. Liver tissues were collected from mice and analyzed by histology, immunohistochemistry, and immunoblotting. RESULTS: AhR was expressed at high levels in quiescent HSCs, but the expression decreased with HSC activation. Activation of HSCs from AhR-knockout mice was accelerated compared with HSCs from wild-type mice. In contrast, TCDD or ITE inhibited spontaneous and transforming growth factor ß-induced activation of HSCs. Mice with disruption of Ahr in HSCs, but not hepatocytes or Kupffer cells, developed more severe fibrosis after administration of CCl4 or bile duct ligation. C57BL/6J mice given ITE did not develop CCl4-induced liver fibrosis, whereas mice without HSC AhR given ITE did develop CCl4-induced liver fibrosis. In studies of mouse and human HSCs, we found that AhR prevents transforming growth factor ß-induced fibrogenesis by disrupting the interaction of Smad3 with ß-catenin, which prevents the expression of genes that mediate fibrogenesis. CONCLUSIONS: In studies of human and mouse HSCs, we found that AhR prevents HSC activation and expression of genes required for liver fibrogenesis. Development of nontoxic AhR agonists or strategies to activate AhR signaling in HSCs might be developed to prevent or treat liver fibrosis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Senescência Celular , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Fígado/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proliferação de Células , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Indóis/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/deficiência , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Proteína Smad3/metabolismo , Tiazóis/farmacologia , beta Catenina/metabolismo
7.
Mar Drugs ; 17(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163697

RESUMO

Largazole, isolated from a marine Cyanobacterium of the genus Symploca, is a potent and selective Class I HDAC (histone deacetylation enzymes) inhibitor. This natural 16-membered macrocyclic depsipeptide features an interesting side chain unit, namely 3-hydroxy-7-mercaptohept-4-enoic acid, which occurs in many other natural sulfur-containing HDAC inhibitors. Notably, one similar fragment, where the amide moiety replaces the trans alkene moiety, appears in Psammaplin A, another marine natural product with potent HDAC inhibitory activities. Inspired by such a structural similarity, we hypothesized the fluoroolefin moiety would mimic both the alkene moiety in Largazole and the amide moiety in Psammaplin A, and thus designed and synthesized two novel fluoro olefin analogs of Largazole. The preliminary biological assays showed that the fluoro analogs possessed comparable Class I HDAC inhibitory effects, indicating that this kind of modification on the side chain of Largazole was tolerable.


Assuntos
Organismos Aquáticos/química , Cianobactérias/química , Depsipeptídeos/síntese química , Depsipeptídeos/farmacologia , Dissulfetos/química , Inibidores de Histona Desacetilases/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Tirosina/análogos & derivados , Alcenos/química , Depsipeptídeos/química , Ativação Enzimática/efeitos dos fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Tiazóis/química , Tirosina/química
8.
Pestic Biochem Physiol ; 157: 26-32, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153474

RESUMO

Nitenpyram is very effective in controlling Nilaparvata lugens (brown planthopper, BPH), and its resistance has been reported in field populations; however, the resistance mechanism remains unclear. In the present study, cross-resistance and resistance mechanisms in nitenpyram-resistant BPH were investigated. A resistant strain (NR) with a high resistance level (164.18-fold) to nitenpyram was evolved through successive selection for 42 generations from a laboratory susceptible strain (NS). The bioassay results showed that the NR exhibited cross-resistance to imidacloprid (37.46-fold), thiamethoxam (71.66-fold), clothianidin (149.17-fold), dinotefuran (98.13-fold), sulfoxaflor (47.24-fold), cycloxaprid (9.33-fold), etofenprox (10.51-fold) and isoprocarb (9.97-fold) but not to triflumezopyrim, chlorpyrifos and buprofezin. The NR showed a 3.21-fold increase in cytochrome P450 monooxygenase (P450) activity compared to that in the NS, while resistance was also synergized (4.03-fold) with the inhibitor piperonyl butoxide (PBO), suggesting a role of P450. Furthermore, the mRNA expression levels of cytochrome P450 (CYP) genes by quantitative real-time PCR results indicated that twelve P450 genes were significantly overexpressed in the NR strain, especially CYP6ER1 (203.22-fold). RNA interference (RNAi) suppression of CYP6ER1 through injection of dsCYP6ER1 led to significant susceptibility in the NR strain. The current study expands our understanding of the nitenpyram resistance mechanism in N. lugens, provides an important reference for integrated pest management (IPM), and enriches the theoretical system of insect toxicology.


Assuntos
Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Animais , Carbamatos/farmacologia , Guanidinas/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Nitrocompostos/farmacologia , Piretrinas/farmacologia , Piridinas/farmacologia , Pirimidinonas/farmacologia , Interferência de RNA , Tiazóis/farmacologia
9.
Eur J Med Chem ; 178: 315-328, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31195172

RESUMO

The dormant and resistant form of Mycobacterium tuberculosis presents a challenge in developing new anti-tubercular drugs. Herein, we report the synthesis and evaluation of trisubstituted thiazoles as antituberculosis agents. The SAR study has identified a requirement of hydrophobic substituent at C2, ester functionality at C4, and various groups with hydrogen bond acceptor character at C5 of thiazole scaffold. This has led to the identification of 13h and 13p as lead compounds. These compounds inhibited the dormant Mycobacterium tuberculosis H37Ra strain and M. tuberculosis H37Rv selectively. Importantly, 13h and 13p were non-toxic to CHO cells. The 13p showed activity against multidrug-resistant tuberculosis isolates.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tiazóis/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
10.
Eur J Med Chem ; 178: 767-781, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31234030

RESUMO

By the analysis of different binding modes with Bruton's tyrosine kinase (BTK), series of novel diphenylthiazole derivatives were rationally designed, synthesized and characterized. Biologically evaluation in biochemistry and cellular assay indicated that, compounds 5m, 5o, 6b, 6c, 6g, 6i, 7h, 7i, 7k, 7m, 7n, 7o and 7s exhibited improved potency against Ramos cell (IC50 = 1.36-8.60 µM) and Raji cell (IC50 = 1.20-14.04 µM) as compared with ibrutinib (IC50 = 14.69 and 15.99 µM, respectively). Especially, compounds 7m and 7n showed 10-time improved potency against Ramos cell viability over ibrutinib. Compound 6b improved 13-fold activity against Raji cell viability than ibrutinib. In addition, active compound 7o potently inhibited C481S mutant BTK with IC50 value of 0.061 µM. Apoptosis analysis of both Ramos and Raji cells indicated that 7o was remarkably more potent than CGI-1746 and ibrutinib. Compound 7o potently inhibited BTK Y223 phosphorylation in Raji cells, and arrested cell cycle progression in the G0/G1 phase in Raji and Ramos cells. This study expanded the structural diversity of BTK inhibitors and compound 7o was discovered as an active lead inhibitor with great potential for further studies.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antineoplásicos/farmacologia , Descoberta de Drogas , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Tiazóis/farmacologia , Tirosina Quinase da Agamaglobulinemia/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química , Células Tumorais Cultivadas
11.
Eur J Med Chem ; 177: 153-170, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132531

RESUMO

The eukaryotic initiation factor 4E (eIF4E) is an emerging anticancer drug target for specific anticancer therapy as a promising approach to overcome drug resistance and promote chemotherapy antitumor efficacy. A series of bromophenol-thiazolylhydrazone hybrids were designed, synthesized and evaluated for their antitumor activities. Among of them, the most potent compound 3e (EGPI-1) could inhibit the eIF4E/eIF4G interaction. Further mechanism study demonstrated EGPI-1 played an antitumor role in multiple modes of action including regulating the activity of eIF4E by inhibiting the phosphorylation of eIF4E and 4EBP1, disrupting mitochondrial function through the mTOR/4EBP1 signaling pathway, and inducing autophagy, apoptosis and ROS generation. Moreover, EGPI-1 showed good safety and favorable pharmacokinetic properties in vivo. These observations demonstrate that EGPI-1 may serve as an excellent lead compound for the development of new anticancer drugs that target the eIF4E/eIF4G interface and as a chemical genetic probe to investigate the role of the eIF4E in biological processes and human diseases.


Assuntos
Antineoplásicos/farmacologia , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4G em Eucariotos/antagonistas & inibidores , Hidrazonas/farmacologia , Tiazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Drogas , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação 4G em Eucariotos/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrazonas/síntese química , Hidrazonas/farmacocinética , Hidrazonas/toxicidade , Masculino , Camundongos , Simulação de Acoplamento Molecular , Fosforilação , Ligação Proteica , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiazóis/síntese química , Tiazóis/farmacocinética , Tiazóis/toxicidade , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Molecules ; 24(9)2019 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31060260

RESUMO

Based on the extensive biological activities of thiazole derivatives against different types of diseases, we are interested in the effective part of many natural compounds, so we synthesized a new series of compounds containing di-, tri- and tetrathiazole moieties. The formation of such derivatives proceeded via reaction of 2-bromo-1-(4-methyl-2-(methylamino)thiazol-5-yl)ethan-1-one with heterocyclic amines, o-aminothiophenol and thiosemicarbazone derivatives. The structure and mechanistic pathways for all products were discussed and proved based on spectral results, in addition to conformational studies. Our aim after the synthesis is to investigate their antimicrobial activity against various types of bacteria and fungi species. Preceeding such an investigation, a molecular docking study was carried out with selected conformers, as representative examples, against three pathogen-proteins. This preliminary stage could support the biological application. The potency of these compounds as antimicrobial agents has been evaluated. The results showed that derivatives which have di- and trithiazole rings displayed high activity that exceeds the used standard antibiotic.


Assuntos
Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Tiazóis/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Testes de Sensibilidade Microbiana , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia
13.
Eur J Med Chem ; 175: 40-48, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071549

RESUMO

Sixteen 5-aryl-substituted isothiazol-3(2H)-one-1,(1)-(di)oxide analogs have been prepared from the corresponding 5-chloroisothiazol-3(2H)-one-1-oxide or -1,1-dioxide by a Suzuki-Miyaura cross-coupling reaction and screened for their inhibition potency against four human carbonic anhydrase isoenzymes: the transmembrane tumor-associated hCA IX and XII and the cytosolic off-target hCA I and II. Most of the synthesized derivatives inhibited hCA IX and XII isoforms in nanomolar range, whereas remained inactive or modestly active against both hCA I and II isoenzymes. In the N-tert-butylisothiazolone series, the 5-phenyl-substituted analog (1a) excelled in the inhibition of tumor-associated hCA IX and XII (Ki = 4.5 and Ki = 4.3 nM, respectively) with excellent selectivity against off target hCA I and II isoenzymes (S > 2222 and S > 2325, respectively). Since the highest inhibition activities were observed with N-tert-butyl derivatives, lacking a zinc-binding group, we suppose to have a new binding mode situated out of the active site. Additionally, three free-NH containing analogs (3a, 4a, 3i) have also been prepared in order to study the impact of free-NH containing N-acyl-sulfinamide- (-SO-NH-CO-) or N-acyl-sulfonamide-type (-SO2-NH-CO-) derivatives on the inhibitory potency and selectivity. Screening experiments evidenced 5-phenylisothiazol-3(2H)-one-1,1-dioxide (4a), the closest saccharin analog, to be the most active derivative with inhibition constants of Ki = 40.3 nM and Ki = 9.6 nM against hCA IX and hCA XII, respectively. The promising biological results support the high potential of 5-arylisothiazolinone-1,(1)-(di)oxides to be exploited for the design of potent and cancer-selective carbonic anhydrase inhibitors.


Assuntos
Anidrase Carbônica IX/efeitos dos fármacos , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/efeitos dos fármacos , Neoplasias/enzimologia , Tiazóis/síntese química , Tiazóis/farmacologia , Humanos , Análise Espectral/métodos , Relação Estrutura-Atividade , Tiazóis/química
14.
Eur J Med Chem ; 175: 49-62, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31075608

RESUMO

Antibiotic resistance remains a pressing medical challenge for which novel antibacterial agents are urgently needed. The phenylthiazole scaffold represents a promising platform to develop novel antibacterial agents for drug-resistant infections. However, enhancing the physicochemical profile of this class of compounds remains a challenging endeavor to address to successfully translate these molecules into novel antibacterial agents in the clinic. We extended our understanding of the SAR of the phenylthiazoles' lipophilic moiety by exploring its ability to accommodate a hydrophilic group or a smaller sized hetero-ring with the objective of enhancing the physicochemical properties of this class of novel antimicrobials. Overall, the 2-thienyl derivative 20 and the hydroxyl-containing derivative 31 emerged as the most promising antibacterial agents inhibiting growth of drug-resistant Staphylococcus aureus at a concentration as low as 1 µg/mL. Remarkably, compound 20 suppressed bacterial undecaprenyl pyrophosphatase (UppP), the molecular target of the phenylthiazole compounds, in a sub nano-molar concentration range (almost 20,000 times more potent than the lead compounds 1a and 1b). Compound 31 possessed the most balanced antibacterial and physicochemical profile. The compound exhibited rapid bactericidal activity against S. aureus, and successfully cleared intracellular S. aureus within infected macrophages. Furthermore, insertion of the hydroxyl group enhanced the aqueous solubility of 31 by more than 50-fold relative to the first-generation lead 1c.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Lipídeos/química , Pirofosfatases/antagonistas & inibidores , Tiazóis/química , Tiazóis/farmacologia , Animais , Antibacterianos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular , Cromatografia Líquida , Macrófagos/microbiologia , Espectrometria de Massas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Relação Estrutura-Atividade
15.
J Immunol Res ; 2019: 1749803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093508

RESUMO

Plasmacytoid dendritic cells (pDCs) express high levels of the toll-like receptors (TLRs) TLR7 and TLR9. In response to TLR7 and TLR9 ligands, pDCs are primary producers of type I interferons. Our previous study demonstrated that pDCs activated by the TLR7 ligand imiquimod (IMQ) and the TLR9 ligand CpG A can kill breast cancer cells in vitro and inhibit tumor growth in vivo. Moreover, we observed a distinctive morphological, phenotypic change in pDCs after activation by IMQ and CpG A. However, the effect of other TLR7 and TLR9 ligands on pDCs remains less understood. In this study, we treat pDCs with the TLR7 ligand IMQ, TLR7/8 ligands (CL097 and CL075), and three TLR9 ligands (different types of CpGs). The size of pDCs increased significantly after activation by TLR7, or TLR7/8 ligands. TLR7, TLR7/8, and TLR9 ligands similarly modulated cytokine release, as well as protein expression of pDC markers, costimulatory molecules, and cytotoxic molecules. Interestingly, TLR7/8 ligands, especially CL097, induced stronger responses. These results are relevant to the further study of the role and mechanism of pDC-induced antitumor effects and may aid in the development of a new strategy for future tumor immunotherapy.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Citocinas/imunologia , Células Dendríticas/efeitos dos fármacos , Imiquimode/farmacologia , Glicoproteínas de Membrana/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Receptor 7 Toll-Like/imunologia , Receptor 8 Toll-Like/imunologia , Animais , Feminino , Imidazóis/farmacologia , Indutores de Interferon/farmacologia , Interferon Tipo I/imunologia , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Quinolinas/farmacologia , Tiazóis/farmacologia
16.
Acta Trop ; 196: 42-47, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31077641

RESUMO

Over the past decade, insecticide resistance to malaria vectors has been identified in 71 malaria endemic countries. This has posed a major global health challenge in the fight against malaria, with declining rates of indoor residual spraying coverage attributed to pyrethroid-resistance. As part of its vector control monitoring strategies, the Bioko Island Malaria Control Project (BIMCP) in Equatorial Guinea conducted routine insecticide resistance bioassays using the WHO's standard susceptibility tests from 2013 to 2018. During the same period, the frequency of the target-site knockdown resistance allele (kdr) in the local vector population was also determined via PCR for detection of the L1014 F mutation. Biochemical analysis for metabolic resistance was also conducted in 2015. From 2016-2017, Fludora™ fusion, a formulated combination of clothianidin (a neonicotinoid) and deltamethrin (a pyrethroid) was evaluated for 9 months on Bioko Island, using the WHO's standard test procedure for determining residual effectiveness of insecticides on sprayed surfaces. In 2016, the mortality rate of the vectors on 0.05% deltamethrin was as low as 38%. The frequency of the West African form of knockdown resistance allele, L1014 F, in the vector population was as high as 80%, and metabolic resistance analysis indicated high upregulated cytochrome P450 s. However, the residual effectiveness of Fludora™ fusion recorded mortalities above 80% after 72 h of exposure for 8 months. Although both target-site knockdown resistance and metabolic resistance to pyrethroids were implicated in the local malaria vector population, Fludora™ fusion was effective under field conditions in controlling the resistant vectors for a period of 8 months on wooden surfaces on Bioko Island and represents a valuable addition to IRS programs, especially in regions with high levels of pyrethroid resistance.


Assuntos
Anopheles/efeitos dos fármacos , Guanidinas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrilos/farmacologia , Piretrinas/farmacologia , Tiazóis/farmacologia , Animais , Guiné Equatorial/epidemiologia , Guanidinas/administração & dosagem , Guanidinas/química , Humanos , Resistência a Inseticidas/genética , Inseticidas/administração & dosagem , Inseticidas/química , Inseticidas/farmacologia , Ilhas , Malária/epidemiologia , Malária/prevenção & controle , Neonicotinoides/administração & dosagem , Neonicotinoides/química , Nitrilos/administração & dosagem , Nitrilos/química , Piretrinas/administração & dosagem , Piretrinas/química , Tiazóis/administração & dosagem , Tiazóis/química
17.
Pancreas ; 48(4): 568-573, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30946236

RESUMO

OBJECTIVES: The study aimed to investigate the involvement of the mammalian target of rapamycin (mTOR) signaling pathway in orexin-A/OX1 receptor-induced insulin secretion in rat insulinoma INS-1 cells. METHODS: Rat insulinoma INS-1 cells were grown and treated with various concentrations of orexin-A, with or without OX1 receptor-selective antagonist SB674042 or the phosphatidylinositol 3-kinase/mTOR antagonist PF-04691502. Insulin release experiments, Western blot analysis, and statistical analysis were conducted using INS-1 cells. RESULTS: Our results showed that treating cells with orexin-A increased the expression of the OX1 receptor and the phosphorylation of mTOR in a concentration-dependent manner. An increase in insulin secretion was also observed for cells treated with orexin-A. We further demonstrated that the increase in insulin secretion was dependent on the activation of the OX1 receptor and mTOR signaling pathway by using the OX1 receptor-selective antagonist SB674042 or the phosphatidylinositol 3-kinase/mTOR antagonist PF-04691502, which abolished the effects of orexin-A treatment. CONCLUSIONS: Our results concluded that orexin-A/OX1 receptor stimulates insulin secretion by activating AKT and its downstream target, mTOR. Therefore, orexins may regulate the energy balance for cell survival with the involvement of mTOR in this process.


Assuntos
Secreção de Insulina/efeitos dos fármacos , Receptores de Orexina/metabolismo , Orexinas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular Tumoral , Insulinoma/metabolismo , Insulinoma/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosfatidilinositol 3-Quinase/antagonistas & inibidores , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação/efeitos dos fármacos , Piridonas/farmacologia , Pirimidinas/farmacologia , Pirrolidinas/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Tiazóis/farmacologia
18.
Inorg Chem ; 58(9): 6485-6494, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31021622

RESUMO

Transplatin is an inactive platinum drug; however, a number of analogues, such as trans-EE and trans-PtTz, demonstrate promising antitumor activity in vitro and in vivo. Although the ultimate target is nuclear DNA, increasing evidence indicate that proteins also play important roles in the display of antitumor activity. The linker histone H1 is situated by the portal between the unwrapped DNA and the nucleosome core. Our recent study revealed that H1 can readily react with cisplatin, and the adducts tend to form ternary complexes with DNA. In this work, we have investigated the reaction of histone H1 with two antitumor-active trans-oriented complexes, trans-EE and trans-PtTz, and the effect of H1 upon the platination of DNA. The results show that trans-platinum drugs are much more reactive than cisplatin toward H1. Interestingly, in addition to the expected bidentate adducts (by displacement of the two labile chlorido ligands), also a tridentate adduct can be formed by displacement of one nonlabile carrier ligand of trans-EE or trans-PtTz. The trans-Pt/H1 adducts can then react with DNA and generate protein-Pt-DNA ternary complexes. Additionally, platinum can be transferred from trans-Pt/H1 adducts to DNA, generating binary trans-Pt/DNA complexes. Such a transfer of the platinum agent to DNA was not observed in the reaction of cisplatin. Furthermore, the detailed investigation carried out on a model peptide indicates that H1 promotes the DNA platination by trans- EE, while it reduces that of trans-PtTz and cisplatin. These results suggest that H1 can play a key role in the DNA platination and modulate the efficacy of different platinum agents.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , DNA/metabolismo , Histonas/metabolismo , Compostos Organoplatínicos/farmacologia , Tiazóis/farmacologia , Antineoplásicos/química , Cisplatino/química , Adutos de DNA/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Compostos Organoplatínicos/química , Tiazóis/química
19.
J Enzyme Inhib Med Chem ; 34(1): 898-908, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30938216

RESUMO

The rapid emergence of bacterial resistance to antibiotics currently available for treating infectious diseases requires effective antimicrobial agents with new structural profiles and mechanisms of action. Twenty-three thiazolin-4-one derivatives were evaluated for their antibacterial activity by determining the growth inhibition zone diameter, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC), against gram-positive and gram-negative bacteria. Compounds 3a-c, 3e-h, 6b-c and 9a-c expressed better MIC values than moxifloxacin, against Staphylococcus aureus. Compounds 3h and 9b displayed similar effect to indolmycin, a tryptophanyl-tRNA ligase inhibitor. Due to their structural analogy to indolmycin, all compounds were subjected to molecular docking on tryptophanyl-tRNA synthetase. Compounds 3a-e, 6a-e, 8 and 9a-e exhibited better binding affinities towards the target enzymes than indolmycin. The antioxidant potential of the compounds was evaluated by four spectrophotometric methods. Thiazolin-4-ones 3e, 6e and 9e presented better antiradical activity than ascorbic acid, trolox and BHT, used as references.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Tiazóis/farmacologia , Triptofano-tRNA Ligase/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/química , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Simulação de Acoplamento Molecular , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química , Triptofano-tRNA Ligase/metabolismo
20.
Molecules ; 24(8)2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30995807

RESUMO

Mycobacterium avium complex (MAC) is a serious disease mainly caused by M. avium and M. intracellulare. Although the incidence of MAC infection is increasing worldwide, only a few agents are clinically used, and their therapeutic effects are limited. Therefore, new anti-MAC agents are needed. Approximately 6600 microbial samples were screened for new anti-mycobacterial agents that inhibit the growth of both M. avium and M. intracellulare, and two culture broths derived from marine actinomycete strains OPMA1245 and OPMA1730 had strong activity. Nosiheptide (1) was isolated from the culture broth of OPMA1245, and griseoviridin (2) and etamycin (viridogrisein) (3) were isolated from the culture broth of OPMA1730. They had potent anti-mycobacterial activity against M. avium and M. intracellulare with minimum inhibitory concentrations (MICs) between 0.024 and 1.56 µg/mL. In addition, a combination of 2 and 3 markedly enhanced the anti-mycobacterial activity against both M. avium and M. intracellulare. Furthermore, a combination 2 and 3 had a therapeutic effect comparable to that of ethambutol in a silkworm infection assay with M. smegmatis.


Assuntos
Antibacterianos/farmacologia , Macrolídeos/farmacologia , Complexo Mycobacterium avium/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Antibacterianos/química , Bombyx/microbiologia , Descoberta de Drogas , Macrolídeos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Infecção por Mycobacterium avium-intracellulare/microbiologia , Infecção por Mycobacterium avium-intracellulare/mortalidade , Peptídeos/química , Tiazóis/química , Tiazóis/farmacologia
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