RESUMO
Autophagy is a critical cellular homeostatic mechanism, the dysfunction of which has been linked to a wide variety of disease states. It is regulated through the activity of specific kinases, in particular Unc-51 like autophagy activating kinase 1 (ULK1) and Phosphatidylinositol 3-kinase vacuolar protein sorting 34 (VPS34), which have both been suggested as potential targets for drug development. To identify new chemical compounds that might provide useful chemical tools or act as starting points for drug development, we screened each protein against the Published Kinase Inhibitor Set (PKIS), a library of known kinase inhibitors. In vitro screening and analysis of the published selectivity profiles of the hits informed the selection of three relatively potent ATP-competitive inhibitors against each target that presented the least number of off-target kinases in common. Cellular assays confirmed potent inhibition of autophagy in response to two of the ULK1 inhibitors and all three of the VPS34 inhibitors. These compounds represent not only a new resource for the study of autophagy but also potential chemical starting points for the validation or invalidation of these two centrally important autophagy kinases in disease models.
Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/antagonistas & inibidores , Autofagia , Classe III de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Descoberta de Drogas , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Osteossarcoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Fosforilação , Células Tumorais CultivadasRESUMO
We used a network of 135 NO2 passive diffusion tube sites to develop land use regression (LUR) models in a UK conurbation. Network sites were divided into four groups (32-35 sites per group) and models developed using combinations of 1-3 groups of "training" sites to evaluate how the number of training sites influenced model performance and residential NO2 exposure estimates for a cohort of 13â¯679 participants. All models explained moderate to high variance in training and independent "hold-out" data (Training adj. R2: 62-89%; Hold-out R2: 44-85%). Average hold-out R2 increased by 9.5%, while average training adj. R2 decreased by 7.2% when the number of training groups was increased from 1 to 3. Exposure estimate precision improved with increasing number of training sites (median intralocation relative standard deviations of 19.2, 10.3, and 7.7% for 1-group, 2-group and 3-group models respectively). Independent 1-group models gave highly variable exposure estimates suggesting that variations in LUR sampling networks with relatively low numbers of sites (≤35) may substantially alter exposure estimates. Collectively, our analyses suggest that use of more than 60 training sites has quantifiable benefits in epidemiological application of LUR models.
Assuntos
Poluentes Atmosféricos , Dióxido de Nitrogênio , Estudos de Coortes , Monitoramento Ambiental , Humanos , Análise de RegressãoRESUMO
G-protein-coupled receptor 84 (GPR84) is a proinflammatory orphan G-protein-coupled receptor implicated in several inflammatory and fibrotic diseases. Several agonist and antagonist ligands have been developed that target GPR84; however, a noncompetitive receptor blocker that was progressed to phase II clinical trials failed to demonstrate efficacy. New high-quality antagonists are required to investigate the pathophysiological role of GPR84 and to validate GPR84 as a therapeutic target. We previously reported the discovery of a novel triazine GPR84 competitive antagonist 1. Here, we describe an extensive structure-activity relationship (SAR) of antagonist 1 and also present in silico docking with supporting mutagenesis studies that reveals a potential binding pose for this type of orthosteric antagonist. Lead compound 42 is a potent GPR84 antagonist with a favorable pharmacokinetic (PK) profile suitable for further drug development.
Assuntos
Receptores Acoplados a Proteínas G , Triazinas , Ligantes , Receptores Acoplados a Proteínas G/metabolismo , Relação Estrutura-Atividade , Triazinas/farmacologiaRESUMO
Starting from compound 1, we utilized biostructural data to successfully evolve an existing series into a new chemotype with a promising overall profile, exemplified by 19.
Assuntos
Desenho de Fármacos , Indanos/química , Indanos/farmacologia , Receptores de AMPA/metabolismo , Sulfonamidas/química , Sulfonamidas/farmacologia , Regulação Alostérica , Animais , Linhagem Celular , Cristalografia por Raios X , Humanos , Indanos/metabolismo , Indanos/farmacocinética , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/metabolismo , Pirazóis/química , Pirazóis/metabolismo , Pirazóis/farmacocinética , Pirazóis/farmacologia , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Sulfonamidas/metabolismo , Sulfonamidas/farmacocinéticaRESUMO
A novel dioxo-triazine series of cathepsin K inhibitors was identified from HTS. A rapid exploratory programme led to the discovery of potent and selective cathepsin K inhibitors, typified by compound 24 which displayed IC(50) values of 17nM against catK and >10,000nM in catL, catB and catS assays.
Assuntos
Catepsina K/antagonistas & inibidores , Inibidores de Cisteína Proteinase/química , Triazinas/química , Sítios de Ligação , Domínio Catalítico , Catepsina K/metabolismo , Cristalografia por Raios X , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Relação Estrutura-Atividade , Triazinas/síntese química , Triazinas/farmacologia , Uracila/análogos & derivados , Uracila/síntese química , Uracila/química , Uracila/farmacologiaRESUMO
Starting from lead compound 1, we demonstrate how X-ray structural data can be used to understand SAR and expediently optimize bioavailability in a novel series of AMPA receptor modulators, furnishing 5 with improved bioavailability and robust in vivo activity.
Assuntos
Aminas/química , Aminas/farmacologia , Desenho de Fármacos , Pirazóis/química , Pirazóis/farmacologia , Receptores de AMPA/metabolismo , Regulação Alostérica , Aminas/síntese química , Aminas/farmacocinética , Animais , Disponibilidade Biológica , Cristalografia por Raios X , Humanos , Modelos Moleculares , Pirazóis/síntese química , Pirazóis/farmacocinética , Ratos , Ratos Wistar , Receptores de AMPA/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Starting from an HTS derived hit 1, application of biostructural data facilitated rapid optimization to lead 22, a novel AMPA receptor modulator. This is the first demonstration of how structure based drug design can be exploited in an optimization program for a glutamate receptor.
Assuntos
Indazóis/química , Receptores de AMPA/química , Tiofenos/química , Regulação Alostérica , Animais , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Indazóis/síntese química , Indazóis/farmacologia , Microssomos/metabolismo , Estrutura Terciária de Proteína , Ratos , Receptores de AMPA/metabolismo , Tiofenos/síntese química , Tiofenos/farmacologiaRESUMO
Starting from previously disclosed equally potent cathepsin K and S inhibitor 4-propyl-6-(3-trifluoromethylphenyl)pyrimidine-2-carbonitrile 1, a novel 2-phenyl-9H-purine-6-carbonitrile scaffold was identified to provide potent and selective cathepsin S inhibitors.
Assuntos
Catepsinas/antagonistas & inibidores , Nitrilas/química , Inibidores de Proteases/química , Purinas/química , Domínio Catalítico , Catepsina K/antagonistas & inibidores , Catepsina K/metabolismo , Catepsinas/metabolismo , Linhagem Celular , Simulação por Computador , Humanos , Nitrilas/síntese química , Nitrilas/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Purinas/síntese química , Purinas/farmacologia , Pirimidinas/químicaRESUMO
6-Phenyl-1H-imidazo[4,5-c]pyridine-4-carbonitrile analogues were identified as potent and selective cathepsin S inhibitor against both purified enzyme and in human JY cell based cellular assays. This core has a very stable thio-trapping nitrile war-head in comparison with the well reported pyrimidine-2-carbonitrile cysteine cathepsin inhibitors. Compound 47 is also very potent in in vivo mouse spleenic Lip10 accumulation assays.
Assuntos
Catepsinas/antagonistas & inibidores , Nitrilas/química , Inibidores de Proteases/química , Piridinas/química , Animais , Sítios de Ligação , Catepsinas/metabolismo , Linhagem Celular , Cristalografia por Raios X , Humanos , Camundongos , Nitrilas/síntese química , Nitrilas/farmacocinética , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacocinética , Piridinas/síntese química , Piridinas/farmacocinética , Relação Estrutura-AtividadeRESUMO
Cyclic AMP promotes EPAC1 and EPAC2 activation through direct binding to a specific cyclic nucleotide-binding domain (CNBD) within each protein, leading to activation of Rap GTPases, which control multiple cell responses, including cell proliferation, adhesion, morphology, exocytosis, and gene expression. As a result, it has become apparent that directed activation of EPAC1 and EPAC2 with synthetic agonists may also be useful for the future treatment of diabetes and cardiovascular diseases. To identify new EPAC agonists we have developed a fluorescent-based, ultra-high-throughput screening (uHTS) assay that measures the displacement of binding of the fluorescent cAMP analogue, 8-NBD-cAMP to the EPAC1 CNBD. Triage of the output of an approximately 350,000 compound screens using this assay identified a benzofuran oxaloacetic acid EPAC1 binder (SY000) that displayed moderate potency using orthogonal assays (competition binding and microscale thermophoresis). We next generated a limited library of 91 analogues of SY000 and identified SY009, with modifications to the benzofuran ring associated with a 10-fold increase in potency towards EPAC1 over SY000 in binding assays. In vitro EPAC1 activity assays confirmed the agonist potential of these molecules in comparison with the known EPAC1 non-cyclic nucleotide (NCN) partial agonist, I942. Rap1 GTPase activation assays further demonstrated that SY009 selectively activates EPAC1 over EPAC2 in cells. SY009 therefore represents a novel class of NCN EPAC1 activators that selectively activate EPAC1 in cellulae.
Assuntos
Acetatos/farmacologia , Benzofuranos/química , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Acetatos/química , Sítios de Ligação , Linhagem Celular , AMP Cíclico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/agonistas , Fatores de Troca do Nucleotídeo Guanina/genética , Ensaios de Triagem em Larga Escala , Humanos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura MolecularRESUMO
OBJECTIVE: This study investigates possible advantages in pulsed over continuous 405-nm light-emitting diode (LED) light for bacterial inactivation and energy efficiency. BACKGROUND: Alternative nonantibiotic methods of disinfection and infection control have become of significant interest. Recent studies have demonstrated the application of systems using 405-nm LEDs for continuous disinfection of the clinical environment, and also for potential treatment of contaminated wounds. METHODS: Liquid suspensions of 103 colony-forming units/mL populations of Staphylococcus aureus were subject to pulsed 405-nm light of different frequencies, duty cycles, and intensities and for different lengths of time. RESULTS: Pulsed exposures with the same average irradiance of 16 mW/cm2 and varying duty cycle (25%, 50%, 75%) showed very similar performance compared with continuous exposures, with 95-98% reduction of S. aureus achieved for all duty cycles. The pulsing frequency was varied in intervals from 100 Hz to 10 kHz and appeared to have little effect on antimicrobial efficacy. However, when comparing pulsed with continuous exposure, an improvement in inactivation per unit optical energy was achieved, with results showing an increase of approximately 83% in optical efficiency. CONCLUSIONS: These results suggest that under pulsed conditions, a lower energy consumption and lower perceived brightness could be achieved, thus potentially providing improved operating conditions for medical/infection control applications without compromising antimicrobial efficacy.