RESUMO
G-protein coupled receptor kinase 2 (GRK2), which is upregulated in the failing heart, appears to play a critical role in heart failure (HF) progression in part because enhanced GRK2 activity promotes dysfunction of ß-adrenergic signaling and myocyte death. An orally bioavailable GRK2 inhibitor could offer unique therapeutic outcomes that cannot be attained by current heart failure treatments that directly target GPCRs or angiotensin-converting enzyme. Herein, we describe the discovery of a potent, selective, and orally bioavailable GRK2 inhibitor, 8h, through high-throughput screening, hit-to-lead optimization, structure-based design, molecular modelling, synthesis, and biological evaluation. In the cellular target engagement assays, 8h enhances isoproterenol-mediated cyclic adenosine 3',5'-monophosphate (cAMP) production in HEK293 cells overexpressing GRK2. Compound 8h was further evaluated in a human stem cell-derived cardiomyocyte (HSC-CM) contractility assay and potentiated isoproterenol-induced beating rate in HSC-CMs.
Assuntos
Quinase 2 de Receptor Acoplado a Proteína G/antagonistas & inibidores , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Animais , Ensaios Enzimáticos , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Estrutura Molecular , Miócitos Cardíacos/efeitos dos fármacos , Ftalazinas/síntese química , Ftalazinas/farmacocinética , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Quinazolinas/síntese química , Quinazolinas/metabolismo , Quinazolinas/farmacocinética , Relação Estrutura-AtividadeRESUMO
The cFMS proto-oncogene encodes for the colony-stimulating factor-1 receptor, a receptor-tyrosine kinase responsible for the differentiation and maturation of certain macrophages. Upon binding its ligand colony-stimulating factor-1 cFMS autophosphorylates, dimerizes, and induces phosphorylation of downstream targets. We report the novel crystal structure of unphosphorylated cFMS in complex with two members of different classes of drug-like protein kinase inhibitors. cFMS exhibits a typical bi-lobal kinase fold, and its activation loop and DFG motif are found to be in the canonical inactive conformation. Both ATP competitive inhibitors are bound in the active site and demonstrate a binding mode similar to that of STI-571 bound to cABL. The DFG motif is prevented from switching into the catalytically competent conformation through interactions with the inhibitors. Activation of cFMS is also inhibited by the juxtamembrane domain, which interacts with residues of the active site and prevents formation of the activated kinase. Together the structures of cFMS provide further insight into the autoinhibition of receptor-tyrosine kinases via their respective juxtamembrane domains; additionally the binding mode of two novel classes of kinase inhibitors will guide the design of novel molecules targeting macrophage-related diseases.
Assuntos
Inibidores de Proteínas Quinases/química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/química , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Receptor de Fator Estimulador de Colônias de Macrófagos/química , Amidas/química , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Humanos , Dados de Sequência Molecular , Proteínas Mutantes Quiméricas/antagonistas & inibidores , Proteínas Mutantes Quiméricas/química , Estrutura Terciária de Proteína/genética , Proto-Oncogene Mas , Quinolonas/química , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Receptor TIE-2/química , Receptor TIE-2/genética , Receptores de Fatores de Crescimento de Fibroblastos/química , Receptores de Fatores de Crescimento de Fibroblastos/genéticaRESUMO
The discovery, SAR, and X-ray crystal structure of novel biarylaminoacyl-(S)-2-cyano-pyrrolidines and biarylaminoacylthiazolidines as potent inhibitors of dipeptidyl peptidase IV (DPP IV) are reported.
Assuntos
Química Farmacêutica/métodos , Cristalografia por Raios X/métodos , Dipeptidil Peptidase 4/química , Inibidores Enzimáticos/farmacologia , Inibidores de Proteases/farmacologia , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Glicemia/metabolismo , Células CACO-2 , Dipeptidil Peptidase 4/metabolismo , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cinética , Camundongos , Modelos Químicos , Modelos Moleculares , Ratos , Relação Estrutura-AtividadeRESUMO
HDM2 binds to an alpha-helical transactivation domain of p53, inhibiting its tumor suppressive functions. A miniaturized thermal denaturation assay was used to screen chemical libraries, resulting in the discovery of a novel series of benzodiazepinedione antagonists of the HDM2-p53 interaction. The X-ray crystal structure of improved antagonists bound to HDM2 reveals their alpha-helix mimetic properties. These optimized molecules increase the transcription of p53 target genes and decrease proliferation of tumor cells expressing wild-type p53.