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1.
Vet Parasitol ; 276: 108991, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31770701

RESUMO

Eimeria tenella, an obligate intracellular parasite, can actively invade the cecal epithelial cells of chickens and cause severe enteric disease. Eukaryotic elongation factor 2 (eEF2) plays a major role in protein synthesis and cell survival. This study aims to explore the exact mechanisms underlying diclazuril inhibition in second-generation merozoites of E. tenella. The eEF2 cDNA of the second-generation merozoites of E. tenella (EtEF2) was cloned by reverse transcriptase polymerase chain reaction and rapid amplification of cDNA ends. Diclazuril-induced expression profiles of EtEF2 were also analyzed. The cloned full-length cDNA (2893 bp) of the EtEF2 nucleotide sequence encompassed a 2499 bp open reading frame (ORF) that encoded a polypeptide of 832 residues with an estimated molecular mass of 93.12 kDa and a theoretical isoelectric point of 5.99. The EtEF2 nucleotide sequence was submitted to the GenBank database with the accession number KF188423. The EtEF2 protein sequence shared 99 % homology with the eEF2 sequence of Toxoplasma gondii (GenBank XP_002367778.1). The GTPase activity domain and ADP-ribosylation domain were conserved signature sequences of the eEF2 gene family. The changes in the transcriptional and translational levels of EtEF2 were detected through quantitative real-time PCR and Western blot analyses. The mRNA expression level of EtEF2 was 2.706 fold increases and the protein level of EtEF2 was increased 67.31 % under diclazuril treatment. In addition, the localization of EtEF2 was investigated through immunofluorescence assay. Experimental results demonstrated that EtEF2 was distributed primarily in the cytoplasm of second-generation merozoites, and its fluorescence intensity was enhanced after diclazuril treatment. These findings indicated that EtEF2 may have an important role in understanding the signaling mechanism underlying the anticoccidial action of diclazuril and could be a promising target for novel drug exploration.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria tenella/efeitos dos fármacos , Quinase do Fator 2 de Elongação/metabolismo , Doenças das Aves Domésticas/tratamento farmacológico , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Eimeria tenella/genética , Quinase do Fator 2 de Elongação/genética , Feminino , Imunofluorescência , Masculino , Merozoítos/efeitos dos fármacos , Merozoítos/genética , Camundongos , Camundongos Endogâmicos BALB C , Nitrilos/farmacologia , Filogenia , Doenças das Aves Domésticas/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Triazinas/farmacologia
2.
Eur J Med Chem ; 183: 111641, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514062

RESUMO

Cyclin dependent kinase 7 (CDK7) plays a double role as it activates several other cyclin dependent kinases and participates to the initiation of transcription. This kinase is overexpressed in various types of tumors. Relatively few selective CDK7 inhibitors have been up to now disclosed. Most of these inhibitors belong to two chemical families: pyrazolopyrimidines and pyrazolotriazines on one side and pyrimidines on another side. They also differ by their molecular mechanism of action. Some are acting as competitive inhibitors and some others are covalent inhibitors. With these tools, the understanding of the potential therapeutic interest of CDK7 inhibitors in cancer is rapidly growing. They display antiproliferative activity against various types of tumors and leukemia and synergies have been identified. Two inhibitors are undergoing clinical testing. The most potent compounds inhibit a large number of cell-lines with IC50 < 200 nM.


Assuntos
Antineoplásicos/química , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Pirimidinas/química , Triazinas/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenvolvimento de Medicamentos , Humanos , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Triazinas/farmacologia
3.
Vet Parasitol ; 273: 105-111, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31473449

RESUMO

Diclazuril, which is widely used for the prevention of coccidiosis in chickens, has a lethal effect on asexual and sexual stages of Eimeria spp. However, little is known about its effect on the exogenous stages of Eimeria spp. In this study, we evaluated the effect of in vitro treatment with 0.2% diclazuril on unsporulated and sporulated oocysts of Eimeria spp. For this purpose, a total of 180 male layer chicks aged one day were randomly divided into 5 experimental groups. Each group was divided into 3 replicates of 12 chicks each. Group 1 (G1) and Group 2 (G2) were negative (non-immunized and non-challenged) and positive (non-immunized and challenged) controls, respectively. Group 3 (G3) was immunized per os with 1.0 × 104 non-diclazuril treated-sporulated oocysts. Groups 4 (G4) was immunized per os with 0.2% diclazuril treated-unsporulated oocysts (1.0 × 104) in which diclazzuril didn't affect sporulation. Group 5 (G5) was immunized per os with 0.2% diclazuril treated-sporulated oocysts (1.0 × 104). Chicks of G2, G3, G4, and G5 were challenged with 7.5 × 104 untreated sporulated oocysts at the age of 21 days, while the group 1 chicks remained unchallenged. G4 and G5 animals immunized with 0.2% diclazuril-treated oocysts showed a significant decrease in bloody diarrhea severity, lesion scores, and oocyst counts in comparison to those immunized with untreated oocysts. Furthermore, histopathologic findings showed a low number of parasitic stages in cecal tissues in G4 and G5. A significant increased body weight gain was observed in Gs 4 and 5 in comparison to G2. In addition, expression levels of IL-2, IL-12, and IFN-γ were significantly increased in G4 and G5. In conclusion, diclazuril is effective in attenuating Eimeria oocysts and thus provides an alternative approach for using diclazuril-treated oocysts to protect chicks against Eimeria challenge.


Assuntos
Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Nitrilos/farmacologia , Oocistos/efeitos dos fármacos , Doenças das Aves Domésticas , Triazinas/farmacologia , Animais , Ceco/parasitologia , Galinhas , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria/patogenicidade , Masculino , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Virulência/efeitos dos fármacos
4.
Pestic Biochem Physiol ; 159: 27-33, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400781

RESUMO

Imidacloprid has been used to control one of most serious pests, Bemisia tabaci. However, B. tabaci has developed imidacloprid resistance mainly by over-expressing CYP6CM1. It was reported that imidacloprid-resistant B. tabaci showed no or low level of cross-resistance against dinotefuran. Here, we expressed CYP6CM1 variants using Sf9/baculovirus and/or Drosophila S2 cells and showed that CYP6CM1 variants metabolized imidacloprid but not dinotefuran. In addition, we demonstrated that imidacloprid and pymetrozine competed for a CYP6CM1 variant more efficiently than dinotefuran, using a luminescent substrate competition assay. These results suggest that lack of metabolic activity of CYP6CM1 variants against dinotefuran caused no or low level of cross-resistance.


Assuntos
Guanidinas/metabolismo , Guanidinas/farmacologia , Hemípteros/efeitos dos fármacos , Hemípteros/metabolismo , Inseticidas/metabolismo , Inseticidas/farmacologia , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Animais , Hemípteros/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Triazinas/metabolismo , Triazinas/farmacologia
5.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370274

RESUMO

Phosphodiesterase 2A (PDE2A) is highly expressed in distinct areas of the brain, which are known to be related to neuropsychiatric diseases. The development of suitable PDE2A tracers for Positron Emission Tomography (PET) would permit the in vivo imaging of the PDE2A and evaluation of disease-mediated alterations of its expression. A series of novel fluorinated PDE2A inhibitors on the basis of a Benzoimidazotriazine (BIT) scaffold was prepared leading to a prospective inhibitor for further development of a PDE2A PET imaging agent. BIT derivatives (BIT1-9) were obtained by a seven-step synthesis route, and their inhibitory potency towards PDE2A and selectivity over other PDEs were evaluated. BIT1 demonstrated much higher inhibition than other BIT derivatives (82.9% inhibition of PDE2A at 10 nM). BIT1 displayed an IC50 for PDE2A of 3.33 nM with 16-fold selectivity over PDE10A. This finding revealed that a derivative bearing both a 2-fluoro-pyridin-4-yl and 2-chloro-5-methoxy-phenyl unit at the 8- and 1-position, respectively, appeared to be the most potent inhibitor. In vitro studies of BIT1 using mouse liver microsomes (MLM) disclosed BIT1 as a suitable ligand for 18F-labeling. Nevertheless, future in vivo metabolism studies are required.


Assuntos
Encéfalo/enzimologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Compostos Radiofarmacêuticos/química , Triazinas/síntese química , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/química , Humanos , Ligantes , Camundongos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacologia , Triazinas/química , Triazinas/farmacologia
6.
Parasitol Res ; 118(9): 2499-2507, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31363921

RESUMO

Stable flies (Stomoxys calcitrans Linnaeus, 1758) can have a considerable negative impact on animal well-being, health, and productivity. Since insecticides constitute the mainstay for their control, this study aimed at assessing the occurrence of insecticide resistance in S. calcitrans on dairy farms in Brandenburg, Germany. First, the susceptibility of stable flies from 40 dairy farms to a deltamethrin-impregnated fabric was evaluated using the FlyBox® field test method. Then, S. calcitrans strains from 10 farms were reared in the laboratory, and the offspring was tested against the adulticides deltamethrin and azamethiphos and the larvicides cyromazine and pyriproxyfen. The FlyBox® method indicated 100% resistance in stable flies against deltamethrin. Later, to the offspring of those 10 established laboratory strains previously caught on suspected dairy farms, these field findings could be confirmed with mortalities well below 90% 24 h following topical application of the calculated LD95 of deltamethrin and azamethiphos. The ten strains could therefore be classified as resistant to the tested insecticides. In contrast, exposure to the insect growth regulators cyromazine and pyriproxyfen at their recommended concentrations demonstrated 100% efficacy. Both larvicides inhibited the moulting process of the stable fly larval stages completely, showing that the stable fly strains tested were susceptible to them. The intensive use of insecticides in recent decades has probably promoted the development of insecticide resistance. Systematic surveys in different livestock production systems and vigilance are therefore deemed necessary for estimating the risk of insecticide resistance development on a nationwide scale.


Assuntos
Resistência a Inseticidas/fisiologia , Inseticidas/farmacologia , Hormônios Juvenis/farmacologia , Larva/efeitos dos fármacos , Muscidae/efeitos dos fármacos , Animais , Fazendas , Alemanha , Nitrilos/farmacologia , Organotiofosfatos/farmacologia , Piretrinas/farmacologia , Piridinas/farmacologia , Triazinas/farmacologia
7.
Arch Pharm (Weinheim) ; 352(9): e1900053, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31380598

RESUMO

The present research focused on designing a quinazoline skeleton, framed via 1,3,5-triazine derivatives (QBT) through field mapping and alignment studies. The QBT derivatives were synthesized via time- and cost-effective protocol. The 3D-QSAR study, computational physicochemical properties, and ADME calculation of the derivatives were performed to establish the affinity towards the biological system. Molecular docking in the adenosine triphosphate binding site of the RET tyrosine kinase domain (PDB ID: 7IVU) was studied to elucidate vital structural residues necessary for bioactivity. The derivatives were evaluated for anticancer potency against TPC-1 cells (thyroid cancer), MCF-7 cells (breast cancer), and one normal cell line (human foreskin fibroblasts) via 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyltetrazolium bromide assay followed by an in ovo CAM assay. The entire series of derivatives (8a-o) showed mild to significant anticancer potency against the selected cancer cell lines.


Assuntos
Antineoplásicos/síntese química , Desenho de Drogas , Inibidores de Proteínas Quinases/síntese química , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Quinazolinas/química , Triazinas/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Estrutura Molecular , Fosforilação , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Relação Quantitativa Estrutura-Atividade , Triazinas/química , Triazinas/farmacologia
8.
Molecules ; 24(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295864

RESUMO

Extracellular acidification is an important feature of tumor microenvironments but has yet to be successfully exploited in cancer therapy. The reversal of the pH gradient across the plasma membrane in cells that regulate intracellular pH (pHi) has potential to drive the selective uptake of weak acids at low extracellular pH (pHe). Here, we investigate the dual targeting of low pHe and hypoxia, another key feature of tumor microenvironments. We prepared eight bioreductive prodrugs based on the benzotriazine di-oxide (BTO) nucleus by appending alkanoic or aminoalkanoic acid sidechains. The BTO acids showed modest selectivity for both low pHe (pH 6.5 versus 7.4, ratios 2 to 5-fold) and anoxia (ratios 2 to 8-fold) in SiHa and FaDu cell cultures. Related neutral BTOs were not selective for acidosis, but had greater cytotoxic potency and hypoxic selectivity than the BTO acids. Investigation of the uptake and metabolism of representative BTO acids confirmed enhanced uptake at low pHe, but lower intracellular concentrations than expected for passive diffusion. Further, the modulation of intracellular reductase activity and competition by the cell-excluded electron acceptor WST-1 suggests that the majority of metabolic reductions of BTO acids occur at the cell surface, compromising the engagement of the resulting free radicals with intracellular targets. Thus, the present study provides support for designing bioreductive prodrugs that exploit pH-dependent partitioning, suggesting, however, that that the approach should be applied to prodrugs with obligate intracellular activation.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Neoplasias/metabolismo , Pró-Fármacos , Triazinas/química , Triazinas/farmacologia , Linhagem Celular Tumoral , Fenômenos Químicos , Relação Dose-Resposta a Droga , Desenho de Drogas , Humanos , Modelos Biológicos , Estrutura Molecular , Oxirredução/efeitos dos fármacos , Óxidos
9.
Nat Commun ; 10(1): 3201, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324758

RESUMO

Pulmonary neuroendocrine (NE) cancer, including small cell lung cancer (SCLC), is a particularly aggressive malignancy. The lineage-specific transcription factors Achaete-scute homolog 1 (ASCL1), NEUROD1 and POU2F3 have been reported to identify the different subtypes of pulmonary NE cancers. Using a large-scale mass spectrometric approach, here we perform quantitative secretome analysis in 13 cell lines that signify the different NE lung cancer subtypes. We quantify 1,626 proteins and identify IGFBP5 as a secreted marker for ASCL1High SCLC. ASCL1 binds to the E-box elements in IGFBP5 and directly regulates its transcription. Knockdown of ASCL1 decreases IGFBP5 expression, which, in turn, leads to hyperactivation of IGF-1R signaling. Pharmacological co-targeting of ASCL1 and IGF-1R results in markedly synergistic effects in ASCL1High SCLC in vitro and in mouse models. We expect that this secretome resource will provide the foundation for future mechanistic and biomarker discovery studies, helping to delineate the molecular underpinnings of pulmonary NE tumors.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/metabolismo , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Azepinas/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Experimentais , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/genética , Fatores de Transcrição de Octâmero/metabolismo , Proteômica , Pirazóis/farmacologia , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Triazinas/farmacologia , Triazóis/farmacologia
11.
Int J Mol Sci ; 20(14)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336820

RESUMO

Among serotonin receptors, the 5-HT6 subtype is the most controversial and the least known in the field of molecular mechanisms. The 5-HT6R ligands can be pivotal for innovative treatment of cognitive impairment, but none has reached pharmacological market, predominantly, due to insufficient "druglikeness" properties. Recently, 1,3,5-triazine-piperazine derivatives were identified as a new chemical family of potent 5-HT6R ligands. For the most active triazine 5-HT6R agents found (1-4), a wider binding profile and comprehensive in vitro evaluation of their drug-like parameters as well as behavioral studies and an influence on body mass in vivo were investigated within this work. Results indicated the most promising pharmacological/druglikeness profiles for 4-((1H-indol-3-yl)methyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (3) and 4-((2-isopropyl-5-methylphenoxy)methyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (4), which displayed a significant procognitive action and specific anxiolytic-like effects in the behavioral tests in vivo together with satisfied pharmaceutical and safety profiles in vitro. The thymol derivative (4) seems to be of higher importance as a new lead candidate, due to the innovative, non-indole and non-sulfone structure with the best 5-HT6R binding properties.


Assuntos
Receptores de Serotonina/química , Agonistas do Receptor de Serotonina/química , Agonistas do Receptor de Serotonina/farmacologia , Triazinas/química , Triazinas/farmacologia , Animais , Disfunção Cognitiva/tratamento farmacológico , Dopamina/química , Dopamina/farmacologia , Células HEK293 , Humanos , Ligantes , Masculino , Memória/efeitos dos fármacos , Redes e Vias Metabólicas , Estrutura Molecular , Ratos , Receptores de Serotonina/metabolismo , Serotonina/química , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/uso terapêutico
12.
Pestic Biochem Physiol ; 157: 60-68, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153478

RESUMO

A series of novel substituted oxazole isoxazole carboxamides derivatives were designed on the basis of active subunit combination. Forty-four novel compounds were synthesized by an efficient one-pot procedure under microwave irradiation. The bioactivity was evaluated as herbicide safener against the injury of chlorsulfuron. It was found that most of the synthesized compounds displayed remarkable protection against chlorsulfuron via enhanced glutathione content and glutathione S transferase activity. Especially compound I-11 exhibited better bioactivity than the safeners isoxadifen-ethyl and R-28725. Molecular docking simulations suggested that the target compounds could compete with chlorsulfuron in the active site of acetolactate synthase, which could explain the protective effects of safeners. The present work demonstrates that the target compounds containing oxazole isoxazole groups could be considered as potential candidates for developing novel safeners in the future.


Assuntos
Herbicidas/química , Herbicidas/farmacologia , Isoxazóis/química , Oxazóis/química , Sulfonamidas/farmacologia , Triazinas/farmacologia , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Relação Estrutura-Atividade , Zea mays/enzimologia
13.
Chem Pharm Bull (Tokyo) ; 67(6): 566-575, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31155562

RESUMO

We report here the development of phenylamino-1,3,5-triazine derivatives as novel nonsteroidal progesterone receptor (PR) antagonists. PR plays key roles in various physiological systems, including the female reproductive system, and PR antagonists are promising candidates for clinical treatment of multiple diseases. By using the phenylamino-1,3,5-triazine scaffold as a template structure, we designed and synthesized a series of 4-cyanophenylamino-1,3,5-triazine derivatives. The synthesized compounds exhibited PR antagonistic activity, and among them, compound 12n was the most potent (IC50 = 0.30 µM); it also showed significant binding affinity to the PR ligand-binding domain. Docking simulation supported the design rationale of the compounds. Our results suggest that the phenylamino-1,3,5-triazine scaffold is a versatile template for development of nonsteroidal PR antagonists and that the developed compounds are promising lead compounds for further structural development of nonsteroidal PR antagonists.


Assuntos
Antineoplásicos/síntese química , Desenho de Drogas , Receptores de Progesterona/antagonistas & inibidores , Triazinas/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Receptores de Progesterona/metabolismo , Relação Estrutura-Atividade , Triazinas/metabolismo , Triazinas/farmacologia
14.
Nucleic Acids Res ; 47(13): 6578-6589, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31188442

RESUMO

Higher-ordered structure motifs of nucleic acids, such as the G-quadruplex (G-4), mismatched and bulge structures, are significant research targets because these structures are involved in genetic control and diseases. Selective alkylation of these higher-order structures is challenging due to the chemical instability of the alkylating agent and side-reactions with the single- or double-strand DNA and RNA. We now report the reactive OFF-ON type alkylating agents, vinyl-quinazolinone (VQ) precursors with a sulfoxide, thiophenyl or thiomethyl group for the OFF-ON control of the vinyl reactivity. The stable VQ precursors conjugated with aminoacridine, which bind to the G-4 DNA, selectively reacted with a T base on the G-4 DNA in contrast to the single- and double-strand DNA. Additionally, the VQ precursor reacted with the T or U base in the AP-site, G-4 RNA and T-T mismatch structures. These VQ precursors would be a new candidate for the T or U specific alkylation in the higher-ordered structures of nucleic acids.


Assuntos
Alquilantes/farmacologia , DNA/efeitos dos fármacos , Conformação de Ácido Nucleico/efeitos dos fármacos , Alquilantes/síntese química , Alquilantes/química , Alquilação , Pareamento de Bases , DNA/química , DNA de Cadeia Simples/química , DNA de Cadeia Simples/efeitos dos fármacos , Quadruplex G/efeitos dos fármacos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Purinas/química , Purinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Relação Estrutura-Atividade , Triazinas/química , Triazinas/farmacologia , Compostos de Vinila/química , Compostos de Vinila/farmacologia
15.
Pharmacology ; 104(3-4): 126-138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31212291

RESUMO

The aim of the present study was to determine the protective effect of novel 1,3,5-triazine-procaine derivatives against myocardial ischemia/reperfusion (I/R) injury. Initially, the experiment has been started by the synthesis of procaine, which later got substituted with diverse 1,3,5-triazine derivatives to furnish the final compounds. The target compounds were tested for nuclear factor-κB (NF-κB) inhibitory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The antioxidant activity of most potent compound 9i was investigated using hydroxyl radical, DPPH, and superoxide anion scavenging assay. Compound 9i was further evaluated for protective effect against myocardial I/R injury on the basis numerous parameters, for example, hemodynamic parameters (left ventricular developed pressure [LVDP], ±dp/dtmax, coronary flow [CF], and heart rate [HR]), myocardial enzymes (creatine kinase and lactate dehydrogenase), thiobarbituric acid reactive substance (TBARS), oxidative stress (super oxide dismutase [SOD], catalase [CAT], glutathione [GSH], and glutathione peroxidise [GPx]), histopathology, western blots analysis for B-cell lymphoma 2 (Bcl-2), Bcl-2-associated x protein (Bax), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), and NF-κB in cardiac tissues. Compounds showed significant inhibition of NF-ĸB transcriptional activity in LPS-stimulated RAW264.7 cells, revealing compound 9i as a most potent derivative. In vitro results showed efficient reduction of reduced hydroxyl radical, DPPH, and superoxide anion by 9i. The level LVDP, ±dp/dtmax, CF, HR, TBARS, SOD, CAT, GSH, GPx, and damaged cardiac histopathology were completely restored to normal in 9i-treated group, as compared to I/R group. In western blot analysis, the expression of Bax, LOX-1, and NF-ĸB was found to be decreased, while the level of Bcl-2 was found to be increased in 9i-treated group. The procaine-1,3,5-triazine derivatives showed significant cardioprotective action via inhibition of NF-ĸB.


Assuntos
Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Procaína/farmacologia , Substâncias Protetoras/farmacologia , Triazinas/farmacologia , Animais , Cardiotônicos/farmacologia , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
16.
Eur J Pharm Sci ; 136: 104938, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132401

RESUMO

Savolitinib is a novel small-molecule selective cMet inhibitor. This work characterized its pharmacokinetics in preclinical phase, established the preclinical relationships between PK, cMet modulation and anti-tumor efficacy. In vitro and in vivo animal studies were performed for PK characterization. Savolitinib showed good absorption, moderate tissue distribution, low to intermediate clearance, and low accumulation. Hepatic oxidative metabolism followed by urinary and biliary excretions was the major elimination pathway. Based on preclinical PK data, human PK profiles were predicted using empirical methods. Pharmacodynamic studies for evaluating cMet inhibition and anti-tumor efficacy were conducted in nude mice bearing Hs746t xenograft. PK/PD models were built to link the PD measurements to nude mouse PK. The established integrated preclinical PK/PD model contained a two-compartment non-linear PK model, a biomarker link model and a tumor growth transit model. The IC50 of cMet inhibition and the concentration achieving half of the maximal Hs746t tumor reduction by savolitinib were equal to 12.5 and 3.7 nM (free drug), respectively. Based on the predicted human PK data, as well as the established PK/PD model in nude mouse, the human PD (cMet inhibition) profiles were also simulated. This research supported clinical development of savolitinib. Understanding the preclinical PK/PD relationship of savolitinib provides translational insights into the cMet-targeted drug development.


Assuntos
Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/farmacocinética , Pirazinas/farmacologia , Pirazinas/farmacocinética , Triazinas/farmacologia , Triazinas/farmacocinética , Animais , Células CACO-2 , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos Nus , Modelos Biológicos , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Eur J Med Chem ; 175: 330-348, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096154

RESUMO

Human DNA topoisomerases represent one of the key targets of modern chemotherapy. An emerging group of catalytic inhibitors of human DNA topoisomerase IIα comprises a new paradigm directed to circumvent the known limitations of topoisomerase II poisons such as cardiotoxicity and induction of secondary tumors. In our previous studies, 4,6-substituted-1,3,5-triazin-2(1H)-ones were discovered as catalytic inhibitors of topo IIα. Here, we report the results of our efforts to optimize several properties of the initial chemical series that did not exhibit cytotoxicity on cancer cell lines. Using an optimized synthetic route, a focused chemical library was designed aimed at further functionalizing substituents at the position 4 of the 1,3,5-triazin-2(1H)-one scaffold to enable additional interactions with the topo IIα ATP binding site. After virtual screening, selected 36 analogues were synthesized and experimentally evaluated for human topo IIα inhibition. The optimized series displayed improved inhibition of topo IIα over the initial series and the catalytic mode of inhibition was confirmed for the selected active compounds. The optimized series also showed cytotoxicity against HepG2 and MCF-7 cell lines and did not induce double-strand breaks, thus displaying a mechanism of action that differs from the topo II poisons on the cellular level. The new series represents a new step in the development of the 4,6-substituted-1,3,5-triazin-2(1H)-one class towards novel efficient anticancer therapies utilizing the catalytic topo IIα inhibition paradigm.


Assuntos
DNA Topoisomerases Tipo II/efeitos dos fármacos , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Triazinas/química , Triazinas/farmacologia , Trifosfato de Adenosina/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Catálise , Quebras de DNA de Cadeia Dupla , Células Hep G2 , Histonas/metabolismo , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/metabolismo
18.
PLoS One ; 14(4): e0215033, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002701

RESUMO

Epoxyeicosatrienoic acids (EETs) are signaling lipids produced by cytochrome P450 epoxygenation of arachidonic acid, which are metabolized by EPHX2 (epoxide hydrolase 2, alias soluble epoxide hydrolase or sEH). EETs have pleiotropic effects, including anti-inflammatory activity. Using a Connectivity Map (CMAP) approach, we identified an inverse-correlation between an exemplar EPHX2 inhibitor (EPHX2i) compound response and an inflammatory bowel disease patient-derived signature. To validate the gene-disease link, we tested a pre-clinical tool EPHX2i (GSK1910364) in a mouse disease model, where it showed improved outcomes comparable to or better than the positive control Cyclosporin A. Up-regulation of cytoprotective genes and down-regulation of proinflammatory cytokine production were observed in colon samples obtained from EPHX2i-treated mice. Follow-up immunohistochemistry analysis verified the presence of EPHX2 protein in infiltrated immune cells from Crohn's patient tissue biopsies. We further demonstrated that GSK2256294, a clinical EPHX2i, reduced the production of IL2, IL12p70, IL10 and TNFα in both ulcerative colitis and Crohn's disease patient-derived explant cultures. Interestingly, GSK2256294 reduced IL4 and IFNγ in ulcerative colitis, and IL1ß in Crohn's disease specifically, suggesting potential differential effects of GSK2256294 in these two diseases. Taken together, these findings suggest a novel therapeutic use of EPHX2 inhibition for IBD.


Assuntos
Colite/tratamento farmacológico , Cicloexilaminas/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Epóxido Hidrolases/antagonistas & inibidores , Doenças Inflamatórias Intestinais/tratamento farmacológico , Triazinas/farmacologia , Animais , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Citocinas/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Feminino , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BL
19.
J Parasitol ; 105(2): 371-378, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31033388

RESUMO

Sarcocystis neurona is a ubiquitous parasite in the eastern United States, which is the principal causative agent in the neurologic disorder equine protozoal myeloencephalitis (EPM). While much is known about this protozoa's life cycle in its natural host, the opossum (Didelphis virginiana), little is known of how it acts in the aberrant equine host, which displays a high incidence of exposure with a relatively low rate of morbidity. For this study, we employed the popular interferon gamma knockout mouse model to determine the potential for recrudescence of S. neurona infection after treatment with the anticoccidial drug diclazuril. Mice were infected with S. neurona merozoites, and 7-days post-infection (DPI) they were treated with diclazuril for 30 or 60 days or not treated at all. All infected non-treated mice developed neurologic signs consistent with S. neurona infection within 30 DPI. All diclazuril-treated infected mice remained clinically normal while on treatment but developed neurologic signs within 60 days of treatment cessation. Histological examination of cerebella from all infected mice demonstrated characteristic lesions of S. neurona infection, regardless of treatment status. Cerebellar samples collected from infected treated mice, displaying neurologic signs, produced viable S. neurona in culture. However, cerebellar samples collected from infected and neurologically normal mice at the end of a 30-day treatment period did not produce viable S. neurona in culture. Analysis of the humoral immune response in infected mice showed that during treatment IgM antibody production decreased, suggesting the organism was sequestered from immune surveillance. The cessation of treatment and subsequent development of neurologic disease resulted in increased IgM antibody production, suggesting recognition by the immune system at that time. Based on the study results the authors propose that diclazuril was able to inhibit the replication and migration of S. neurona but not fully eliminate the parasite, suggesting recrudescence of infection after treatment is possible.


Assuntos
Coccidiostáticos/uso terapêutico , Encefalomielite/parasitologia , Nitrilos/uso terapêutico , Sarcocystis/patogenicidade , Sarcocistose/parasitologia , Triazinas/uso terapêutico , Animais , Encéfalo/parasitologia , Cerebelo/parasitologia , Cerebelo/patologia , Coccidiostáticos/farmacologia , Encefalomielite/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Imunoglobulinas/sangue , Imuno-Histoquímica , Interferon gama/genética , Masculino , Camundongos , Camundongos Knockout , Nitrilos/farmacologia , Gambás/parasitologia , Recidiva , Sarcocystis/efeitos dos fármacos , Sarcocistose/tratamento farmacológico , Triazinas/farmacologia , Células Vero
20.
Exp Parasitol ; 201: 34-41, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31034815

RESUMO

Ovine Eimeria spp. infections cause increased mortality, reduced welfare and substantial economic losses, and anticocccidials are important for their control. Recent reports of anticoccidial resistance against ovine Eimeria spp. necessitate the development of in vitro methods for the detection of reduced anticoccidial efficacy, especially since the in vivo methods are both expensive, time consuming and requires the use of otherwise healthy animals. The aim of the present study was therefore to approach a preliminary standardization of in vitro assays for evaluation of the efficacy of the most commonly used anticoccidials in ruminants. For this purpose, apart from the evaluation of inhibition of oocyst sporulation, most effort was concentrated on assessment of the capacity of the different anticoccidials to inhibit both the invasion and further development (up to the first schizogony) of E. ninakohlyakimovae sporozoites in bovine colonic epithelial cells (BCEC). For this purpose, infected cultures were monitored 1, 8 and 15 days post infection to determine the infection rate, number of immature schizonts and number, size and appearance of mature schizonts, respectively. No clear inhibitory effect was found with any of the anticoccidial formulations tested, and we could not identify why there were no measurable effects from the different anticoccidials. Despite the lack of positive results, further investigations should be encouraged, as this could decrease the need for animal experiments and could be used in the initial assessment of anticoccidial efficacy of new drugs.


Assuntos
Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Doenças das Cabras/parasitologia , Animais , Bovinos , Células Cultivadas , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Colo/citologia , Colo/parasitologia , Decoquinato/farmacologia , Resistência a Medicamentos , Eimeria/crescimento & desenvolvimento , Eimeria/isolamento & purificação , Células Epiteliais/parasitologia , Fezes/parasitologia , Doenças das Cabras/tratamento farmacológico , Cabras , Mucosa Intestinal/citologia , Mucosa Intestinal/parasitologia , Nitrilos/farmacologia , Oocistos/isolamento & purificação , Esquizontes/efeitos dos fármacos , Esquizontes/crescimento & desenvolvimento , Esporozoítos/isolamento & purificação , Sulfonamidas/farmacologia , Triazinas/farmacologia
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