RESUMEN
The inhibition of aldosterone synthase (CYP11B2) may be an effective treatment of hypertension and heart failure, among other ailments. Previously reported benzimidazole CYP11B2 inhibitors led the way for bioisosteric imidazopyridines that are both potent and selective over CYP11B1.
Asunto(s)
Citocromo P-450 CYP11B2/antagonistas & inhibidores , Imidazoles/farmacología , Piridinas/farmacología , Animales , Cricetulus , Humanos , Imidazoles/síntesis química , Imidazoles/química , Imidazoles/farmacocinética , Macaca mulatta , Masculino , Microsomas Hepáticos/metabolismo , Piridinas/síntesis química , Piridinas/química , Piridinas/farmacocinética , Ratas Wistar , Esteroide 11-beta-Hidroxilasa/antagonistas & inhibidores , Relación Estructura-ActividadRESUMEN
We report the discovery and hit-to-lead optimization of a structurally novel indazole series of CYP11B2 inhibitors. Benchmark compound 34 from this series displays potent inhibition of CYP11B2, high selectivity versus related steroidal and hepatic CYP targets, and lead-like physical and pharmacokinetic properties. On the basis of these and other data, the indazole series was progressed to lead optimization for further refinement.
Asunto(s)
Antihipertensivos/farmacología , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Hipertensión/tratamiento farmacológico , Indazoles/farmacología , Animales , Antihipertensivos/síntesis química , Antihipertensivos/farmacocinética , Inhibidores de la Aromatasa/síntesis química , Inhibidores de la Aromatasa/farmacocinética , Inhibidores de la Aromatasa/farmacología , Línea Celular , Cricetulus , Inhibidores del Citocromo P-450 CYP2D6/síntesis química , Inhibidores del Citocromo P-450 CYP2D6/farmacocinética , Inhibidores del Citocromo P-450 CYP2D6/farmacología , Humanos , Indazoles/síntesis química , Indazoles/farmacocinética , Macaca mulatta , Masculino , Ratas Sprague-Dawley , Estereoisomerismo , Esteroide 11-beta-Hidroxilasa/antagonistas & inhibidoresRESUMEN
Glucagon and insulin have opposing action in governing glucose homeostasis. In type 2 diabetes mellitus (T2DM), plasma glucagon is characteristically elevated, contributing to increased gluconeogenesis and hyperglycemia. Therefore, glucagon receptor (GCGR) antagonism has been proposed as a pharmacologic approach to treat T2DM. In support of this concept, a potent small-molecule GCGR antagonist (GRA), MK-0893, demonstrated dose-dependent efficacy to reduce hyperglycemia, with an HbA1c reduction of 1.5% at the 80 mg dose for 12 weeks in T2DM. However, GRA treatment was associated with dose-dependent elevation of plasma LDL-cholesterol (LDL-c). The current studies investigated the cause for increased LDL-c. We report findings that link MK-0893 with increased glucagon-like peptide 2 and cholesterol absorption. There was not, however, a GRA-related modulation of cholesterol synthesis. These findings were replicated using structurally diverse GRAs. To examine potential pharmacologic mitigation, coadministration of ezetimibe (a potent inhibitor of cholesterol absorption) in mice abrogated the GRA-associated increase of LDL-c. Although the molecular mechanism is unknown, our results provide a novel finding by which glucagon and, hence, GCGR antagonism govern cholesterol metabolism.
Asunto(s)
Colesterol/sangre , Pirazoles/farmacología , Receptores de Glucagón/antagonistas & inhibidores , beta-Alanina/análogos & derivados , Animales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Humanos , Hipercolesterolemia/inducido químicamente , Concentración 50 Inhibidora , Absorción Intestinal , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Pirazoles/efectos adversos , beta-Alanina/efectos adversos , beta-Alanina/farmacologíaRESUMEN
The voltage-gated potassium channels Kv2.1 and Kv2.2 are highly expressed in pancreatic islets, yet their contribution to islet hormone secretion is not fully understood. Here we investigate the role of Kv2 channels in pancreatic islets using a combination of genetic and pharmacologic approaches. Pancreatic ß-cells from Kv2.1(-/-) mice possess reduced Kv current and display greater glucose-stimulated insulin secretion (GSIS) relative to WT ß-cells. Inhibition of Kv2.x channels with selective peptidyl [guangxitoxin-1E (GxTX-1E)] or small molecule (RY796) inhibitors enhances GSIS in isolated wild-type (WT) mouse and human islets, but not in islets from Kv2.1(-/-) mice. However, in WT mice neither inhibitor improved glucose tolerance in vivo. GxTX-1E and RY796 enhanced somatostatin release in isolated human and mouse islets and in situ perfused pancreata from WT and Kv2.1(-/-) mice. Kv2.2 silencing in mouse islets by adenovirus-small hairpin RNA (shRNA) specifically enhanced islet somatostatin, but not insulin, secretion. In mice lacking somatostatin receptor 5, GxTX-1E stimulated insulin secretion and improved glucose tolerance. Collectively, these data show that Kv2.1 regulates insulin secretion in ß-cells and Kv2.2 modulates somatostatin release in δ-cells. Development of selective Kv2.1 inhibitors without cross inhibition of Kv2.2 may provide new avenues to promote GSIS for the treatment of type 2 diabetes.
Asunto(s)
Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Canales de Potasio Shab/metabolismo , Somatostatina/metabolismo , Adulto , Animales , Proteínas de Artrópodos , Benzamidas/farmacología , Células Cultivadas , Fenómenos Electrofisiológicos , Femenino , Glucosa/farmacología , Humanos , Secreción de Insulina , Células Secretoras de Insulina/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Técnicas de Placa-Clamp , Péptidos/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Unión Proteica , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Canales de Potasio Shab/antagonistas & inhibidores , Canales de Potasio Shab/genética , Venenos de Araña/farmacología , Adulto JovenRESUMEN
Efforts to modify the central proline portion of lead compound 4 lead to the discovery of novel prolylcarboxypeptidase (PrCP) inhibitors. Especially, replacement with alanine afforded compound 19 displaying more potent human and mouse PrCP inhibitory activity than 4 and an overall comparable profile.
Asunto(s)
Alanina/química , Carboxipeptidasas/antagonistas & inhibidores , Descubrimiento de Drogas , Alanina/farmacología , Animales , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Concentración 50 Inhibidora , Ratones , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Novel prolylcarboxypeptidase (PrCP) inhibitors with nanomolar IC(50) values were prepared by replacing the previously described dichlorobenzimidazole-substituted pyrrolidine amides with a variety of substituted benzylamine amides. In contrast to prior series, the compounds demonstrated minimal inhibition shift in whole serum and minimal recognition by P-glycoprotein (P-gp) efflux transporters. The compounds were also cell permeable and demonstrated in vivo brain exposure. The in vivo effect of compound (S)-6e on weight loss in an established diet-induced obesity (eDIO) mouse model was studied.
Asunto(s)
Bencimidazoles/farmacología , Encéfalo/metabolismo , Carboxipeptidasas/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Amidas/química , Animales , Transporte Biológico , Peso Corporal , Encéfalo/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Concentración 50 Inhibidora , Ratones , Modelos Químicos , Obesidad/tratamiento farmacológico , Pirrolidinas/química , Factores de TiempoRESUMEN
A new structural class of potent prolylcarboxypeptidase (PrCP) inhibitors was discovered by high-throughput screening. The series possesses a tractable SAR profile with sub-nanomolar in vitro IC(50) values. Compared to prior inhibitors, the new series demonstrated minimal activity shifts in pure plasma and complete ex vivo plasma target engagement in mouse plasma at the 20 h post-dose time point (po). In addition, the in vivo level of CNS and non-CNS drug exposure was measured.
Asunto(s)
Carboxipeptidasas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos , Animales , Butanoles/síntesis química , Butanoles/química , Butanoles/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Concentración 50 Inhibidora , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Obesidad/tratamiento farmacológico , Pirrolidinas/síntesis química , Pirrolidinas/química , Pirrolidinas/farmacologíaRESUMEN
GPR40 is a class A G-protein coupled receptor (GPCR) mainly expressed in pancreas, intestine, and brain. Its endogenous ligand is long-chain fatty acids, which activate GPR40 after meal ingestion to induce secretion of incretins in the gut, including GLP-1, GIP, and PYY, the latter control appetite and glucose metabolism. For its involvement in satiety regulation and metabolic homeostasis, partial and AgoPAM (Positive Allosteric Modulation agonist) GPR40 agonists had been developed for type 2 diabetes (T2D) by many pharmaceutical companies. The proof-of-concept of GPR40 for control of hyperglycemia was achieved by clinical trials of partial GPR40 agonist, TAK-875, demonstrating a robust decrease in HbA1c (-1.12%) after chronic treatment in T2D. The development of TAK-875, however, was terminated due to liver toxicity in 2.7% patients with more than 3-fold increase of ALT in phase II and III clinical trials. Different mechanisms had since been proposed to explain the drug-induced liver injury, including acyl glucuronidation, inhibition of mitochondrial respiration and hepatobiliary transporters, ROS generation, etc. In addition, activation of GPR40 by AgoPAM agonists in pancreas was also linked to ß-cell damage in rats. Notwithstanding the multiple safety concerns on the development of small-molecule GPR40 agonists for T2D, some partial and AgoPAM GPR40 agonists are still under clinical development. Here we review the most recent progress of GPR40 agonists development and the possible mechanisms of the side effects in different organs, and discuss the possibility of developing novel strategies that retain the robust efficacy of GPR40 agonists for metabolic disorders while avoid toxicities caused by off-target and on-target mechanisms.
RESUMEN
Identification of selective ion channel inhibitors represents a critical step for understanding the physiological role that these proteins play in native systems. In particular, voltage-gated potassium (K(V)2) channels are widely expressed in tissues such as central nervous system, pancreas, and smooth muscle, but their particular contributions to cell function are not well understood. Although potent and selective peptide inhibitors of K(V)2 channels have been characterized, selective small molecule K(V)2 inhibitors have not been reported. For this purpose, high-throughput automated electrophysiology (IonWorks Quattro; Molecular Devices, Sunnyvale, CA) was used to screen a 200,000-compound mixture (10 compounds per sample) library for inhibitors of K(V)2.1 channels. After deconvolution of 190 active samples, two compounds (A1 and B1) were identified that potently inhibit K(V)2.1 and the other member of the K(V)2 family, K(V)2.2 (IC(50), 0.1-0.2 µM), and that possess good selectivity over K(V)1.2 (IC(50) >10 µM). Modeling studies suggest that these compounds possess a similar three-dimensional conformation. Compounds A1 and B1 are >10-fold selective over Na(V) channels and other K(V) channels and display weak activity (5-9 µM) on Ca(V) channels. The biological activity of compound A1 on native K(V)2 channels was confirmed in electrophysiological recordings of rat insulinoma cells, which are known to express K(V)2 channels. Medicinal chemistry efforts revealed a defined structure-activity relationship and led to the identification of two compounds (RY785 and RY796) without significant Ca(V) channel activity. Taken together, these newly identified channel inhibitors represent important tools for the study of K(V)2 channels in biological systems.
Asunto(s)
Descubrimiento de Drogas/métodos , Bloqueadores de los Canales de Potasio/química , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio Shab/antagonistas & inhibidores , Animales , Células CHO , Cricetinae , Cricetulus , Humanos , Ratas , Canales de Potasio Shab/fisiología , Relación Estructura-ActividadRESUMEN
A series of benzimidazole pyrrolidinyl amides containing a piperidinyl group were discovered as novel prolylcarboxypeptidase (PrCP) inhibitors. Low-nanomolar IC(50)'s were achieved for several analogs, of which compound 9b displayed modest ex vivo target engagement in eDIO mouse plasma. Compound 9b was also studied in vivo for its effect on weight loss and food intake in an eDIO mouse model and the results will be discussed.
Asunto(s)
Amidas , Bencimidazoles , Carboxipeptidasas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos , Pirrolidinas , Amidas/química , Amidas/farmacología , Animales , Bencimidazoles/química , Bencimidazoles/farmacología , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Concentración 50 Inhibidora , Ratones , Estructura Molecular , Pirrolidinas/química , Pirrolidinas/farmacología , Relación Estructura-ActividadRESUMEN
Proprotein convertase subtilisin-like/kexin type 9 (PCSK9) is a key regulator of plasma LDL-cholesterol (LDL-C) and a clinically validated target for the treatment of hypercholesterolemia and coronary artery disease. Starting from second-generation lead structures such as 2, we were able to refine these structures to obtain extremely potent bi- and tricyclic PCSK9 inhibitor peptides. Optimized molecules such as 44 demonstrated sufficient oral bioavailability to maintain therapeutic levels in rats and cynomolgus monkeys after dosing with an enabled formulation. We demonstrated target engagement and LDL lowering in cynomolgus monkeys essentially identical to those observed with the clinically approved, parenterally dosed antibodies. These molecules represent the first report of highly potent and orally bioavailable macrocyclic peptide PCSK9 inhibitors with overall profiles favorable for potential development as once-daily oral lipid-lowering agents. In this manuscript, we detail the design criteria and multiparameter optimization of this novel series of PCSK9 inhibitors.
Asunto(s)
Inhibidores de PCSK9/farmacología , Péptidos Cíclicos/farmacología , Administración Oral , Animales , Disponibilidad Biológica , Cristalografía por Rayos X , Macaca fascicularis , Estructura Molecular , Inhibidores de PCSK9/química , Inhibidores de PCSK9/farmacocinética , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacocinética , Ratas , Relación Estructura-ActividadRESUMEN
Proprotein convertase subtilisin-like/kexin type 9 (PCSK9) is a key regulator of plasma LDL-cholesterol (LDL-C) and a clinically validated target for the treatment of hypercholesterolemia and coronary artery disease. In this paper, we describe a series of novel cyclic peptides derived from an mRNA display screen which inhibit the protein-protein interaction between PCSK9 and LDLR. Using a structure-based drug design approach, we were able to modify our original screening lead 2 to optimize the potency and metabolic stability and minimize the molecular weight to provide novel bicyclic next-generation PCSK9 inhibitor peptides such as 78. These next-generation peptides serve as a critical foundation for continued exploration of potential oral, once-a-day PCSK9 therapeutics for the treatment of cardiovascular disease.
Asunto(s)
Diseño de Fármacos , Inhibidores Enzimáticos/metabolismo , Inhibidores de PCSK9 , Proproteína Convertasa 9/metabolismo , ARN Mensajero/metabolismo , Animales , Células Cultivadas , Cristalografía por Rayos X/métodos , Inhibidores Enzimáticos/química , Femenino , Humanos , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos C57BL , Proproteína Convertasa 9/química , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , ARN Mensajero/química , Ratas , Ratas Wistar , Relación Estructura-ActividadRESUMEN
Proprotein convertase substilisin-like/kexin type 9 (PCSK9) is a serine protease involved in a protein-protein interaction with the low-density lipoprotein (LDL) receptor that has both human genetic and clinical validation. Blocking this protein-protein interaction prevents LDL receptor degradation and thereby decreases LDL cholesterol levels. Our pursuit of small-molecule direct binders for this difficult to drug PPI target utilized affinity selection/mass spectrometry, which identified one confirmed hit compound. An X-ray crystal structure revealed that this compound was binding in an unprecedented allosteric pocket located between the catalytic and C-terminal domain. Optimization of this initial hit, using two distinct strategies, led to compounds with high binding affinity to PCSK9. Direct target engagement was demonstrated in the cell lysate with a cellular thermal shift assay. Finally, ligand-induced protein degradation was shown with a proteasome recruiting tag attached to the high-affinity allosteric ligand for PCSK9.
Asunto(s)
Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Proproteína Convertasa 9/metabolismo , Proteolisis/efectos de los fármacos , Inhibidores de Serina Proteinasa/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Humanos , Ligandos , Modelos Moleculares , Estructura Molecular , Inhibidores de Serina Proteinasa/química , Bibliotecas de Moléculas Pequeñas/químicaRESUMEN
Herein we report the discovery and hit-to-lead optimization of a series of spirocyclic piperidine aldosterone synthase (CYP11B2) inhibitors. Compounds from this series display potent CYP11B2 inhibition, good selectivity versus related CYP enzymes, and lead-like physical and pharmacokinetic properties.
RESUMEN
We report the discovery of a benzimidazole series of CYP11B2 inhibitors. Hit-to-lead and lead optimization studies identified compounds such as 32, which displays potent CYP11B2 inhibition, high selectivity versus related CYP targets, and good pharmacokinetic properties in rat and rhesus. In a rhesus pharmacodynamic model, 32 produces dose-dependent aldosterone lowering efficacy, with no apparent effect on cortisol levels.
RESUMEN
DGAT2 plays a critical role in hepatic triglyceride production, and data suggests that inhibition of DGAT2 could prove to be beneficial in treating a number of disease states. This article documents the discovery and optimization of a selective small molecule inhibitor of DGAT2 as well as pharmacological proof of biology in a mouse model of triglyceride production.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Isoquinolinas/química , Isoquinolinas/farmacología , Triglicéridos/metabolismo , Animales , Diacilglicerol O-Acetiltransferasa/metabolismo , Descubrimiento de Drogas , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacocinética , Humanos , Isoquinolinas/administración & dosificación , Isoquinolinas/farmacocinética , Masculino , Ratones , Ratones Endogámicos C57BL , Triglicéridos/sangreRESUMEN
Hit-to-lead efforts resulted in the discovery of compound 19, a potent CYP11B2 inhibitor that displays high selectivity vs related CYPs, good pharmacokinetic properties in rat and rhesus, and lead-like physical properties. In a rhesus pharmacodynamic model, compound 19 displays robust, dose-dependent aldosterone lowering efficacy, with no apparent effect on cortisol levels.
RESUMEN
Hyperglucagonemia is implicated in the pathophysiology of hyperglycemia. Antagonism of the glucagon receptor (GCGR) thus represents a potential approach to diabetes treatment. Herein we report the characterization of GRA1, a novel small-molecule GCGR antagonist that blocks glucagon binding to the human GCGR (hGCGR) and antagonizes glucagon-induced intracellular accumulation of cAMP with nanomolar potency. GRA1 inhibited glycogenolysis dose-dependently in primary human hepatocytes and in perfused liver from hGCGR mice, a transgenic line of mouse that expresses the hGCGR instead of the murine GCGR. When administered orally to hGCGR mice and rhesus monkeys, GRA1 blocked hyperglycemic responses to exogenous glucagon. In several murine models of diabetes, acute and chronic dosing with GRA1 significantly reduced blood glucose concentrations and moderately increased plasma glucagon and glucagon-like peptide-1. Combination of GRA1 with a dipeptidyl peptidase-4 inhibitor had an additive antihyperglycemic effect in diabetic mice. Hepatic gene-expression profiling in monkeys treated with GRA1 revealed down-regulation of numerous genes involved in amino acid catabolism, an effect that was paralleled by increased amino acid levels in the circulation. In summary, GRA1 is a potent glucagon receptor antagonist with strong antihyperglycemic efficacy in preclinical models and prominent effects on hepatic gene-expression related to amino acid metabolism.
Asunto(s)
Regulación de la Expresión Génica , Hipoglucemiantes/farmacología , Pirazoles/farmacología , Receptores de Glucagón/antagonistas & inhibidores , beta-Alanina/análogos & derivados , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Perfilación de la Expresión Génica , Glucagón/sangre , Glucagón/química , Glucógeno/metabolismo , Glucogenólisis , Hepatocitos/efectos de los fármacos , Hormonas/sangre , Humanos , Radioisótopos de Yodo/química , Hígado/metabolismo , Macaca mulatta , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Modelos Químicos , beta-Alanina/farmacologíaRESUMEN
A potent, selective glucagon receptor antagonist 9m, N-[(4-{(1S)-1-[3-(3,5-dichlorophenyl)-5-(6-methoxynaphthalen-2-yl)-1H-pyrazol-1-yl]ethyl}phenyl)carbonyl]-ß-alanine, was discovered by optimization of a previously identified lead. Compound 9m is a reversible and competitive antagonist with high binding affinity (IC(50) of 6.6 nM) and functional cAMP activity (IC(50) of 15.7 nM). It is selective for glucagon receptor relative to other family B GPCRs, showing IC(50) values of 1020 nM for GIPR, 9200 nM for PAC1, and >10000 nM for GLP-1R, VPAC1, and VPAC2. Compound 9m blunted glucagon-induced glucose elevation in hGCGR mice and rhesus monkeys. It also lowered ambient glucose levels in both acute and chronic mouse models: in hGCGR ob/ob mice it reduced glucose (AUC 0-6 h) by 32% and 39% at 3 and 10 mpk single doses, respectively. In hGCGR mice on a high fat diet, compound 9m at 3, and 10 mpk po in feed lowered blood glucose levels by 89% and 94% at day 10, respectively, relative to the difference between the vehicle control and lean hGCGR mice. On the basis of its favorable biological and DMPK properties, compound 9m (MK-0893) was selected for further preclinical and clinical evaluations.