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1.
Nature ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578523

RESUMO

The integrity of the mammalian epidermis depends on a balance of proliferation and differentiation in the resident population of stem cells1. The kinase RIPK4 and the transcription factor IRF6 are mutated in severe developmental syndromes in humans, and mice lacking these genes display epidermal hyperproliferation and soft-tissue fusions that result in neonatal lethality2-5. Our understanding of how these genes control epidermal differentiation is incomplete. Here we show that the role of RIPK4 in mouse development requires its kinase activity; that RIPK4 and IRF6 expressed in the epidermis regulate the same biological processes; and that the phosphorylation of IRF6 at Ser413 and Ser424 primes IRF6 for activation. Using RNA sequencing (RNA-seq), histone chromatin immunoprecipitation followed by sequencing (ChIP-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) of skin in wild-type and IRF6-deficient mouse embryos, we define the transcriptional programs that are regulated by IRF6 during epidermal differentiation. IRF6 was enriched at bivalent promoters, and IRF6 deficiency caused defective expression of genes that are involved in the metabolism of lipids and the formation of tight junctions. Accordingly, the lipid composition of the stratum corneum of Irf6-/- skin was abnormal, culminating in a severe defect in the function of the epidermal barrier. Collectively, our results explain how RIPK4 and IRF6 function to ensure the integrity of the epidermis and provide mechanistic insights into why developmental syndromes that are characterized by orofacial, skin and genital abnormalities result when this axis goes awry.

2.
Bioorg Med Chem Lett ; 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348490

RESUMO

Endothelial lipase (EL) inhibitors have been shown to elevate HDL-C levels in pre-clinical murine models and have potential benefit in prevention and treatment of cardiovascular diseases. Modification of the 1-ethyl-3-hydroxy-1,5-dihydro-2H-pyrrol-2-one (DHP) lead, 1, led to the discovery of a series of potent tetrahydropyrimidinedione (THP) EL inhibitors. Synthesis and SAR studies including modification of the amide group, together with changes on the pyrimidinone core led to a series of arylcycloalkyl, indanyl, and tetralinyl substituted 5-amino or 5-hydroxypyrimidinedione-4-carboxamides. Several compounds were advanced to PK evaluation. Among them, compound 4a was one of the most potent with measurable ELHDL hSerum potency and compound 3g demonstrated the best overall pharmacokinetic parameters.

3.
Cell ; 174(5): 1158-1171.e19, 2018 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-30057110

RESUMO

Characterizing cell surface receptors mediating viral infection is critical for understanding viral tropism and developing antiviral therapies. Nevertheless, due to challenges associated with detecting protein interactions on the cell surface, the host receptors of many human pathogens remain unknown. Here, we build a library consisting of most single transmembrane human receptors and implement a workflow for unbiased and high-sensitivity detection of receptor-ligand interactions. We apply this technology to elucidate the long-sought receptor of human cytomegalovirus (HCMV), the leading viral cause of congenital birth defects. We identify neuropilin-2 (Nrp2) as the receptor for HCMV-pentamer infection in epithelial/endothelial cells and uncover additional HCMV interactors. Using a combination of biochemistry, cell-based assays, and electron microscopy, we characterize the pentamer-Nrp2 interaction and determine the architecture of the pentamer-Nrp2 complex. This work represents an important approach to the study of host-pathogen interactions and provides a framework for understanding HCMV infection, neutralization, and the development of novel anti-HCMV therapies.

4.
ACS Med Chem Lett ; 9(7): 673-678, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30034599

RESUMO

Screening of a small set of nonselective lipase inhibitors against endothelial lipase (EL) identified a potent and reversible inhibitor, N-(3-(3,4-dichlorophenyl)propyl)-3-hydroxy-1-methyl-2-oxo-1,2-dihydropyridine-4-carboxamide (5; EL IC50 = 61 nM, ELHDL IC50 = 454 nM). Deck mining identified a related hit, N-(3-(3,4-dichlorophenyl)propyl)-4-hydroxy-1-methyl-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxamide (6a; EL IC50 = 41 nM, ELHDL IC50 = 1760 nM). Both compounds were selective against lipoprotein lipase (LPL) but nonselective versus hepatic lipase (HL). Optimization of compound 6a for EL inhibition using HDL as substrate led to N-(4-(3,4-dichlorophenyl)butan-2-yl)-1-ethyl-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxamide (7c; EL IC50 = 148 nM, ELHDL IC50 = 218 nM) having improved PK over compound 6a, providing a tool molecule to test for the ability to increase HDL-cholesterol (HDL-C) levels in vivo using a reversible EL inhibitor. Compound 7c did not increase HDL-C in vivo despite achieving plasma exposures targeted on the basis of enzyme activity and protein binding demonstrating the need to develop more physiologically relevant in vitro assays to guide compound progression for in vivo evaluation.

5.
Structure ; 26(5): 767-777.e5, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29706531

RESUMO

Receptor-interacting protein kinase 4 (RIPK4) is a highly conserved regulator of epidermal differentiation. Members of the RIPK family possess a common kinase domain as well as unique accessory domains that likely dictate subcellular localization and substrate preferences. Mutations in human RIPK4 manifest as Bartsocas-Papas syndrome (BPS), a genetic disorder characterized by severe craniofacial and limb abnormalities. We describe the structure of the murine Ripk4 (MmRipk4) kinase domain, in ATP- and inhibitor-bound forms. The crystallographic dimer of MmRipk4 is similar to those of RIPK2 and BRAF, and we show that the intact dimeric entity is required for MmRipk4 catalytic activity through a series of engineered mutations and cell-based assays. We also assess the impact of BPS mutations on protein structure and activity to elucidate the molecular origins of the disease.

6.
Exp Neurol ; 297: 168-178, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28822839

RESUMO

While numerous changes in the GABA system have been identified in models of Fragile X Syndrome (FXS), alterations in subunits of the GABAA receptors (GABAARs) that mediate tonic inhibition are particularly intriguing. Considering the key role of tonic inhibition in controlling neuronal excitability, reduced tonic inhibition could contribute to FXS-associated disorders such as hyperactivity, hypersensitivity, and increased seizure susceptibility. The current study has focused on the expression and function of the δ subunit of the GABAAR, a major subunit involved in tonic inhibition, in granule cells of the dentate gyrus in the Fmr1 knockout (KO) mouse model of FXS. Electrophysiological studies of dentate granule cells revealed a marked, nearly four-fold, decrease in tonic inhibition in the Fmr1 KO mice, as well as reduced effects of two δ subunit-preferring pharmacological agents, THIP and DS2, supporting the suggestion that δ subunit-containing GABAARs are compromised in the Fmr1 KO mice. Immunohistochemistry demonstrated a small but statistically significant decrease in δ subunit labeling in the molecular layer of the dentate gyrus in Fmr1 KO mice compared to wildtype (WT) littermates. The discrepancy between the large deficits in GABA-mediated tonic inhibition in granule cells in the Fmr1 KO mice and only modest reductions in immunolabeling of the δ subunit led to studies of surface expression of the δ subunit. Cross-linking experiments followed by Western blot analysis demonstrated a small, non-significant decrease in total δ subunit protein in the hippocampus of Fmr1 KO mice, but a four-fold decrease in surface expression of the δ subunit in these mice. No significant changes were observed in total or surface expression of the α4 subunit protein, a major partner of the δ subunit in the forebrain. Postembedding immunogold labeling for the δ subunit demonstrated a large, three-fold, decrease in the number of symmetric synapses with immunolabeling at perisynaptic locations in Fmr1 KO mice. While α4 immunogold particles were also reduced at perisynaptic locations in the Fmr1 KO mice, the labeling was increased at synaptic sites. Together these findings suggest that, in the dentate gyrus, altered surface expression of the δ subunit, rather than a decrease in δ subunit expression alone, could be limiting δ subunit-mediated tonic inhibition in this model of FXS. Finding ways to increase surface expression of the δ subunit of the GABAAR could be a novel approach to treatment of hyperexcitability-related alterations in FXS.


Assuntos
Giro Denteado/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Inibição Neural/fisiologia , Subunidades Proteicas/biossíntese , Receptores de GABA-A/biossíntese , Animais , Giro Denteado/patologia , Giro Denteado/ultraestrutura , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/patologia , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Subunidades Proteicas/genética , Receptores de GABA-A/genética
7.
Cell ; 168(5): 878-889.e29, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28235199

RESUMO

Design of small molecules that disrupt protein-protein interactions, including the interaction of RAS proteins and their effectors, may provide chemical probes and therapeutic agents. We describe here the synthesis and testing of potential small-molecule pan-RAS ligands, which were designed to interact with adjacent sites on the surface of oncogenic KRAS. One compound, termed 3144, was found to bind to RAS proteins using microscale thermophoresis, nuclear magnetic resonance spectroscopy, and isothermal titration calorimetry and to exhibit lethality in cells partially dependent on expression of RAS proteins. This compound was metabolically stable in liver microsomes and displayed anti-tumor activity in xenograft mouse cancer models. These findings suggest that pan-RAS inhibition may be an effective therapeutic strategy for some cancers and that structure-based design of small molecules targeting multiple adjacent sites to create multivalent inhibitors may be effective for some proteins.


Assuntos
Antineoplásicos/farmacologia , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/química , Animais , Antineoplásicos/química , Calorimetria , Linhagem Celular , Fibroblastos/metabolismo , Xenoenxertos , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras , Transdução de Sinais , Bibliotecas de Moléculas Pequenas
8.
Bioanalysis ; 8(15): 1611-1622, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27397670

RESUMO

BACKGROUND: Isomerization of aspartic acid and deamidation of asparagine are two common amino acid modifications that are of particular concern if located within the complementarity-determining region of therapeutic antibodies. Questions arise as to the extent of modification occurring in circulation due to potential exposure of the therapeutic antibody to different pH regimes. RESULTS: To enable evaluation of site-specific isomerization and deamidation of human mAbs in vivo, immunoprecipitation (IP) has been combined with LC-MS providing selective enrichment, separation and detection of naive and modified forms of tryptic peptides comprising complementarity-determining region sequences. CONCLUSION: IP-LC-MS can be applied to simultaneously quantify in vivo drug concentrations and measure the extent of isomerization or deamidation in PK studies conducted during the drug discovery stage.


Assuntos
Anticorpos Monoclonais/química , Asparagina/análise , Ácido Aspártico/análise , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/sangue , Cromatografia Líquida/métodos , Humanos , Imunoprecipitação/métodos , Isomerismo , Macaca fascicularis , Masculino , Espectrometria de Massas em Tandem/métodos
9.
J Neurosci ; 35(49): 16142-58, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26658866

RESUMO

UNLABELLED: The role of GABAA receptor (GABAAR)-mediated tonic inhibition in interneurons remains unclear and may vary among subgroups. Somatostatin (SOM) interneurons in the hilus of the dentate gyrus show negligible expression of nonsynaptic GABAAR subunits and very low tonic inhibition. To determine the effects of ectopic expression of tonic GABAAR subtypes in these neurons, Cre-dependent viral vectors were used to express GFP-tagged GABAAR subunits (α6 and δ) selectively in hilar SOM neurons in SOM-Cre mice. In single-transfected animals, immunohistochemistry demonstrated strong expression of either the α6 or δ subunit; in cotransfected animals, both subunits were consistently expressed in the same neurons. Electrophysiology revealed a robust increase of tonic current, with progressively larger increases following transfection of δ, α6, and α6/δ subunits, respectively, indicating formation of functional receptors in all conditions and likely coassembly of the subunits in the same receptor following cotransfection. An in vitro model of repetitive bursting was used to determine the effects of increased tonic inhibition in hilar SOM interneurons on circuit activity in the dentate gyrus. Upon cotransfection, the frequency of GABAAR-mediated bursting in granule cells was reduced, consistent with a reduction in synchronous firing among hilar SOM interneurons. Moreover, in vivo studies of Fos expression demonstrated reduced activation of α6/δ-cotransfected neurons following acute seizure induction by pentylenetetrazole. The findings demonstrate that increasing tonic inhibition in hilar SOM interneurons can alter dentate gyrus circuit activity during strong stimulation and suggest that tonic inhibition of interneurons could play a role in regulating excessive synchrony within the network. SIGNIFICANCE STATEMENT: In contrast to many hippocampal interneurons, somatostatin (SOM) neurons in the hilus of the dentate gyrus have very low levels of nonsynaptic GABAARs and exhibit very little tonic inhibition. In an effort to increase tonic inhibition selectively in these interneurons, we used Cre-dependent viral vectors in SOM-Cre mice to achieve interneuron-specific expression of the nonsynaptic GABAAR subunits (α6 and δ) in vivo. We show, for the first time, that such recombinant GFP-tagged GABAAR subunits are expressed robustly, assemble to form functional receptors, substantially increase tonic inhibition in SOM interneurons, and alter circuit activity within the dentate gyrus.


Assuntos
Giro Denteado/citologia , Rede Nervosa/metabolismo , Neurônios/metabolismo , Receptores de GABA-A/metabolismo , Somatostatina/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Animais , Giro Denteado/efeitos dos fármacos , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Vetores Genéticos/metabolismo , Humanos , Isoxazóis/farmacologia , Masculino , Camundongos , Camundongos Transgênicos , Inibição Neural/efeitos dos fármacos , Inibição Neural/genética , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Pentilenotetrazol/farmacologia , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Pirimidinas/farmacologia , Receptores de GABA-A/genética , Somatostatina/genética
10.
J Med Chem ; 58(22): 9010-26, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26524347

RESUMO

Cholesteryl ester transfer protein (CETP) inhibitors raise HDL-C in animals and humans and may be antiatherosclerotic by enhancing reverse cholesterol transport (RCT). In this article, we describe the lead optimization efforts resulting in the discovery of a series of triphenylethanamine (TPE) ureas and amides as potent and orally available CETP inhibitors. Compound 10g is a potent CETP inhibitor that maximally inhibited cholesteryl ester (CE) transfer activity at an oral dose of 1 mg/kg in human CETP/apoB-100 dual transgenic mice and increased HDL cholesterol content and size comparable to torcetrapib (1) in moderately-fat fed hamsters. In contrast to the off-target liabilities with 1, no blood pressure increase was observed with 10g in rat telemetry studies and no increase of aldosterone synthase (CYP11B2) was detected in H295R cells. On the basis of its preclinical profile, compound 10g was advanced into preclinical safety studies.


Assuntos
Anticolesterolemiantes/síntese química , Anticolesterolemiantes/farmacologia , Benzamidas/síntese química , Benzamidas/farmacologia , Benzilaminas/síntese química , Benzilaminas/farmacologia , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Animais , Anticolesterolemiantes/farmacocinética , Aterosclerose/tratamento farmacológico , Benzamidas/farmacocinética , Benzilaminas/farmacocinética , Pressão Sanguínea/efeitos dos fármacos , Linhagem Celular , Colesterol/metabolismo , HDL-Colesterol/sangue , Cricetinae , Citocromo P-450 CYP11B2/antagonistas & inibidores , Cães , Descoberta de Drogas , Humanos , Macaca fascicularis , Masculino , Mesocricetus , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Quinolinas/farmacologia , Ratos , Ratos Sprague-Dawley
11.
Nat Commun ; 6: 8986, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26593090

RESUMO

Geranyl-CoA carboxylase (GCC) is essential for the growth of Pseudomonas organisms with geranic acid as the sole carbon source. GCC has the same domain organization and shares strong sequence conservation with the related biotin-dependent carboxylases 3-methylcrotonyl-CoA carboxylase (MCC) and propionyl-CoA carboxylase (PCC). Here we report the crystal structure of the 750-kDa α6ß6 holoenzyme of GCC, which is similar to MCC but strikingly different from PCC. The structures provide evidence in support of two distinct lineages of biotin-dependent acyl-CoA carboxylases, one carboxylating the α carbon of a saturated organic acid and the other carboxylating the γ carbon of an α-ß unsaturated acid. Structural differences in the active site region of GCC and MCC explain their distinct substrate preferences. Especially, a glycine residue in GCC is replaced by phenylalanine in MCC, which blocks access by the larger geranyl-CoA substrate. Mutation of this residue in the two enzymes can change their substrate preferences.


Assuntos
Proteínas de Bactérias/química , Carbono-Carbono Ligases/química , Pseudomonas/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biotina/metabolismo , Carbono-Carbono Ligases/genética , Carbono-Carbono Ligases/metabolismo , Cinética , Modelos Moleculares , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Pseudomonas/química , Pseudomonas/genética , Especificidade por Substrato
12.
ChemMedChem ; 9(10): 2327-43, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24989964

RESUMO

Current antithrombotic discovery efforts target compounds that are highly efficacious in thrombus reduction with less bleeding liability than the standard of care. Preclinical data suggest that P2Y1 antagonists may have lower bleeding liabilities than P2Y12 antagonists while providing similar antithrombotic efficacy. This article describes our continuous SAR efforts in a series of 7-hydroxyindolinyl diaryl ureas. When dosed orally, 4-trifluoromethyl-7-hydroxy-3,3-dimethylindolinyl analogue 4 was highly efficacious in a model of arterial thrombosis in rats with limited bleeding. The chemically labile CF3 group in 4 was then transformed to various groups via a novel one-step synthesis, yielding a series of potent P2Y1 antagonists. Among them, the 4-benzothiazole-substituted indolines had desirable PK properties in rats, specifically, low clearance and small volume of distribution. In addition, compound 40 had high i.v. exposure and modest bioavailability, giving it the best overall profile.


Assuntos
Antagonistas do Receptor Purinérgico P2Y/farmacologia , Ureia/análogos & derivados , Animais , Humanos , Espectroscopia de Ressonância Magnética , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Espectrometria de Massas por Ionização por Electrospray , Ureia/farmacocinética , Ureia/farmacologia
13.
J Med Chem ; 57(14): 6150-64, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-24931384

RESUMO

Adenosine diphosphate (ADP)-mediated platelet aggregation is signaled through two distinct G protein-coupled receptors (GPCR) on the platelet surface: P2Y12 and P2Y1. Blocking P2Y12 receptor is a clinically well-validated strategy for antithrombotic therapy. P2Y1 antagonists have been shown to have the potential to provide equivalent antithrombotic efficacy as P2Y12 inhibitors with reduced bleeding in preclinical animal models. We have previously reported the discovery of a potent and orally bioavailable P2Y1 antagonist, 1. This paper describes further optimization of 1 by introducing 4-aryl groups at the hydroxylindoline in two series. In the neutral series, 10q was identified with excellent potency and desirable pharmacokinetic (PK) profile. It also demonstrated similar antithrombotic efficacy with less bleeding compared with the known P2Y12 antagonist prasugrel in rabbit efficacy/bleeding models. In the basic series, 20c (BMS-884775) was discovered with an improved PK and liability profile over 1. These results support P2Y1 antagonism as a promising new antiplatelet target.


Assuntos
Descoberta de Drogas , Indóis/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y1/metabolismo , Animais , Coagulação Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Indóis/química , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/síntese química , Inibidores da Agregação de Plaquetas/química , Antagonistas do Receptor Purinérgico P2Y/síntese química , Antagonistas do Receptor Purinérgico P2Y/química , Coelhos , Ratos , Relação Estrutura-Atividade , Trombose/tratamento farmacológico
14.
Bioorg Med Chem Lett ; 24(11): 2481-5, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24767843

RESUMO

Blockade of the P2Y1 receptor is important to the treatment of thrombosis with potentially improved safety margins compared with P2Y12 receptor antagonists. Investigation of a series of urea surrogates of the diaryl urea lead 3 led to the discovery of 2-amino-1,3,4-thiadiazoles in the 7-hydroxy-N-neopentyl spiropiperidine indolinyl series as potent P2Y1 receptor antagonists, among which compound 5a was the most potent and the first non-urea analog with platelet aggregation (PA) IC50 less than 0.5 µM with 10 µM ADP. Several 2-amino-1,3,4-thiadiazole analogs such as 5b and 5f had a more favorable pharmacokinetic profile, such as higher Ctrough, lower Cl, smaller Vdss, and similar bioavailability compared with 3.


Assuntos
Indóis/química , Piperidinas/química , Receptores Purinérgicos P2Y1/metabolismo , Tiadiazóis/farmacologia , Animais , Relação Dose-Resposta a Droga , Humanos , Indóis/administração & dosagem , Estrutura Molecular , Piperidinas/administração & dosagem , Ratos , Relação Estrutura-Atividade , Tiadiazóis/administração & dosagem , Tiadiazóis/química
15.
Bioorg Med Chem Lett ; 24(5): 1294-8, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24513044

RESUMO

Spiropiperidine indoline-substituted diaryl ureas had been identified as antagonists of the P2Y1 receptor. Enhancements in potency were realized through the introduction of a 7-hydroxyl substitution on the spiropiperidinylindoline chemotype. SAR studies were conducted to improve PK and potency, resulting in the identification of compound 3e, a potent, orally bioavailable P2Y1 antagonist with a suitable PK profile in preclinical species. Compound 3e demonstrated a robust antithrombotic effect in vivo and improved bleeding risk profile compared to the P2Y12 antagonist clopidogrel in rat efficacy/bleeding models.


Assuntos
Compostos de Fenilureia/química , Inibidores da Agregação de Plaquetas/química , Antagonistas do Receptor Purinérgico P2Y/química , Receptores Purinérgicos P2Y1/química , Tiazóis/química , Ureia/análogos & derivados , Administração Oral , Animais , Cães , Meia-Vida , Macaca fascicularis , Compostos de Fenilureia/farmacocinética , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/farmacocinética , Inibidores da Agregação de Plaquetas/farmacologia , Inibidores da Agregação de Plaquetas/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Ratos , Receptores Purinérgicos P2Y1/metabolismo , Relação Estrutura-Atividade , Tiazóis/farmacocinética , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Trombose/tratamento farmacológico , Ureia/farmacocinética , Ureia/farmacologia , Ureia/uso terapêutico
17.
Bioorg Med Chem Lett ; 23(24): 6825-8, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24269480

RESUMO

A number of new amine scaffolds with good inhibitory activity in the ADP-induced platelet aggregation assay have been found to be potent antagonists of the P2Y1 receptor. SAR optimization led to the identification of isoindoline 3c and piperidine 4a which showed good in vitro binding and functional activities, as well as improved aqueous solubility. Among them, the piperidine 4a showed the best overall profile with favorable PK parameters.


Assuntos
Aminas/química , Agonistas do Receptor Purinérgico P2Y/química , Receptores Purinérgicos P2Y1/química , Ureia/análogos & derivados , Difosfato de Adenosina/farmacologia , Aminas/síntese química , Aminas/farmacocinética , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Meia-Vida , Humanos , Microssomos Hepáticos/metabolismo , Piperidinas/química , Inibidores da Agregação de Plaquetas/síntese química , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/farmacocinética , Ligação Proteica , Agonistas do Receptor Purinérgico P2Y/síntese química , Agonistas do Receptor Purinérgico P2Y/farmacocinética , Ratos , Receptores Purinérgicos P2Y1/metabolismo , Relação Estrutura-Atividade , Ureia/síntese química , Ureia/farmacocinética
18.
J Med Chem ; 56(22): 9275-95, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24164581

RESUMO

Preclinical antithrombotic efficacy and bleeding models have demonstrated that P2Y1 antagonists are efficacious as antiplatelet agents and may offer a safety advantage over P2Y12 antagonists in terms of reduced bleeding liabilities. In this article, we describe the structural modification of the tert-butyl phenoxy portion of lead compound 1 and the subsequent discovery of a novel series of conformationally constrained ortho-anilino diaryl ureas. In particular, spiropiperidine indoline-substituted diaryl ureas are described as potent, orally bioavailable small-molecule P2Y1 antagonists with improved activity in functional assays and improved oral bioavailability in rats. Homology modeling and rat PK/PD studies on benchmark compound 3l will also be presented. Compound 3l was our first P2Y1 antagonist to demonstrate a robust oral antithrombotic effect with mild bleeding liability in the rat thrombosis and hemostasis models.


Assuntos
Desenho de Drogas , Conformação Molecular , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Receptores Purinérgicos P2Y1/metabolismo , Compostos de Espiro/farmacologia , Compostos de Espiro/farmacocinética , Ureia/farmacologia , Ureia/farmacocinética , Animais , Disponibilidade Biológica , Humanos , Indóis/química , Modelos Moleculares , Compostos de Fenilureia/química , Compostos de Fenilureia/metabolismo , Antagonistas do Receptor Purinérgico P2Y/química , Antagonistas do Receptor Purinérgico P2Y/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Purinérgicos P2Y1/química , Homologia de Sequência de Aminoácidos , Compostos de Espiro/química , Compostos de Espiro/metabolismo , Ureia/química , Ureia/metabolismo
19.
J Neurosci ; 33(36): 14392-405, 2013 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-24005292

RESUMO

Axonal sprouting of excitatory neurons is frequently observed in temporal lobe epilepsy, but the extent to which inhibitory interneurons undergo similar axonal reorganization remains unclear. The goal of this study was to determine whether somatostatin (SOM)-expressing neurons in stratum (s.) oriens of the hippocampus exhibit axonal sprouting beyond their normal territory and innervate granule cells of the dentate gyrus in a pilocarpine model of epilepsy. To obtain selective labeling of SOM-expressing neurons in s. oriens, a Cre recombinase-dependent construct for channelrhodopsin2 fused to enhanced yellow fluorescent protein (ChR2-eYFP) was virally delivered to this region in SOM-Cre mice. In control mice, labeled axons were restricted primarily to s. lacunosum-moleculare. However, in pilocarpine-treated animals, a rich plexus of ChR2-eYFP-labeled fibers and boutons extended into the dentate molecular layer. Electron microscopy with immunogold labeling demonstrated labeled axon terminals that formed symmetric synapses on dendritic profiles in this region, consistent with innervation of granule cells. Patterned illumination of ChR2-labeled fibers in s. lacunosum-moleculare of CA1 and the dentate molecular layer elicited GABAergic inhibitory responses in dentate granule cells in pilocarpine-treated mice but not in controls. Similar optical stimulation in the dentate hilus evoked no significant responses in granule cells of either group of mice. These findings indicate that under pathological conditions, SOM/GABAergic neurons can undergo substantial axonal reorganization beyond their normal territory and establish aberrant synaptic connections. Such reorganized circuitry could contribute to functional deficits in inhibition in epilepsy, despite the presence of numerous GABAergic terminals in the region.


Assuntos
Neurônios GABAérgicos/patologia , Interneurônios/patologia , Somatostatina/metabolismo , Estado Epiléptico/patologia , Animais , Axônios/ultraestrutura , Dendritos/ultraestrutura , Giro Denteado/patologia , Neurônios GABAérgicos/fisiologia , Hipocampo/patologia , Interneurônios/metabolismo , Interneurônios/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Inibição Neural , Optogenética , Estimulação Luminosa , Pilocarpina/toxicidade , Terminações Pré-Sinápticas/fisiologia , Terminações Pré-Sinápticas/ultraestrutura , Somatostatina/genética , Estado Epiléptico/induzido quimicamente
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