RESUMEN
Lymphangioleiomyomatosis (LAM) is a cystic lung disease of women resulting from mutations in tuberous sclerosis complex (TSC) genes that suppress the mammalian target of rapamycin complex 1 (mTORC1) pathway. mTORC1 activation enhances a plethora of anabolic cellular functions, mainly via the activation of mRNA translation through stimulation of ribosomal protein S6 kinase (S6K1)/ribosomal protein S6 (S6) and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1)/eukaryotic translation initiation factor 4E (eIF4E). Rapamycin (sirolimus), an allosteric inhibitor of mTORC1, stabilises lung function in many but not all LAM patients and, upon cessation of the drug, disease progression resumes. At clinically tolerable concentrations, rapamycin potently inhibits the ribosomal S6K1/S6 translation ribosome biogenesis and elongation axis, but not the translation 4E-BP1/eIF4E initiation axis. In this mini-review, we propose that inhibition of mTORC1-driven translation initiation is an obvious but underappreciated therapeutic strategy in LAM, TSC and other mTORC1-driven diseases.
Asunto(s)
Linfangioleiomiomatosis , Femenino , Humanos , Linfangioleiomiomatosis/diagnóstico , Linfangioleiomiomatosis/tratamiento farmacológico , Linfangioleiomiomatosis/genética , Factor 4E Eucariótico de Iniciación/genética , Factor 4E Eucariótico de Iniciación/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Sirolimus/farmacologíaRESUMEN
Lymphangioleiomyomatosis (LAM) is a rare fatal cystic lung disease due to bi-allelic inactivating mutations in tuberous sclerosis complex (TSC1/TSC2) genes coding for suppressors of the mechanistic target of rapamycin complex 1 (mTORC1). The origin of LAM cells is still unknown. Here, we profile a LAM lung compared to an age- and sex-matched healthy control lung as a hypothesis-generating approach to identify cell subtypes that are specific to LAM. Our single-cell RNA sequencing (scRNA-seq) analysis reveals novel mesenchymal and transitional alveolar epithelial states unique to LAM lung. This analysis identifies a mesenchymal cell hub coordinating the LAM disease phenotype. Mesenchymal-restricted deletion of Tsc2 in the mouse lung produces a mTORC1-driven pulmonary phenotype, with a progressive disruption of alveolar structure, a decline in pulmonary function, increase of rapamycin-sensitive expression of WNT ligands, and profound female-specific changes in mesenchymal and epithelial lung cell gene expression. Genetic inactivation of WNT signaling reverses age-dependent changes of mTORC1-driven lung phenotype, but WNT activation alone in lung mesenchyme is not sufficient for the development of mouse LAM-like phenotype. The alterations in gene expression are driven by distinctive crosstalk between mesenchymal and epithelial subsets of cells observed in mesenchymal Tsc2-deficient lungs. This study identifies sex- and age-specific gene changes in the mTORC1-activated lung mesenchyme and establishes the importance of the WNT signaling pathway in the mTORC1-driven lung phenotype.
Asunto(s)
Pulmón/metabolismo , Linfangioleiomiomatosis/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Mesodermo/metabolismo , Factores de Edad , Anciano , Animales , Femenino , Humanos , Pulmón/efectos de los fármacos , Pulmón/fisiopatología , Linfangioleiomiomatosis/tratamiento farmacológico , Linfangioleiomiomatosis/genética , Linfangioleiomiomatosis/fisiopatología , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Mesodermo/efectos de los fármacos , Ratones , Factores Sexuales , Sirolimus/administración & dosificación , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo , Vía de Señalización WntRESUMEN
Cysteinyl leukotrienes are proinflammatory mediators with a clinically established role in asthma and a human genetic and preclinical role in cardiovascular pathology. Given that cardiovascular disease has a critical inflammatory component, the aim of this work was to conduct an observational study to verify whether the use of a cysteinyl leukotriene antagonist, namely, montelukast, may protect asthmatic patients from a major cardiovascular event and, therefore, represent an innovative adjunct therapy to target an inflammatory component in cardiovascular disease. We performed an observational retrospective 3-year study on eight hundred adult asthmatic patients 18 years or older in Albania, equally distributed into two cohorts, exposed or nonexposed to montelukast usage, matched by age and gender according to information reported in the data collection. Patients with a previous history of myocardial infarction or ischemic stroke were excluded. In summary, 37 (4.6%) of the asthmatic patients, 32 nonexposed, and five exposed to montelukast suffered a major cardiovascular event during the 3-year observation period. All the cardiovascular events, in either group, occurred among patients with an increased cardiovascular risk. Our analyses demonstrate that, independent from gender, exposure to montelukast remained a significant protective factor for incident ischemic events (78% or 76% risk reduction depending on type of analysis). The event-free Kaplan-Meier survival curves confirmed the lower cardiovascular event incidence in patients exposed to montelukast. Our data suggest that there is a potential preventative role of montelukast for incident cardiac ischemic events in the older asthmatic population, indicating a comorbidity benefit of montelukast usage in asthmatics by targeting cysteinyl leukotriene-driven cardiac disease inflammation.
RESUMEN
Lymphangioleiomyomatosis (LAM) is a rare metastatic cystic lung disease due to a mutation in a TSC tumor suppressor, resulting in hyperactive mTOR growth pathways. Sirolimus (rapamycin), an allosteric mTORC1 inhibitor, is a therapeutic option for women with LAM but it only maintains lung volume during treatment and does not provide benefit for all LAM patients. The two major mTORC1 protein synthesis pathways are via S6K/S6 or 4E-BP/eIF4E activation. We aimed to investigate rapamycin in combination with compounds that target associated growth pathways, with the potential to be additive to rapamycin. In this study we demonstrated that rapamycin, at a clinically tolerable concentration (10 nM), inhibited the phosphorylation of S6, but not the critical eIF4E releasing Thr 37/46 phosphorylation sites of 4E-BP1 in TSC2-deficient LAM-derived cells. We also characterized the abundant protein expression of peIF4E within LAM lesions. A selective MNK1/2 inhibitor eFT508 inhibited the phosphorylation of eIF4E but did not reduce TSC2-null cell growth. In contrast, a PI3K/mTOR inhibitor omipalisib blocked the phosphorylation of Akt and both S6K/S6 and 4E-BP/eIF4E branches, and additively decreased the growth of TSC2-null cells with rapamycin. Omipalisib, or another inhibitor of both major mTORC1 growth pathways and pAkt, might provide therapeutic options for TSC2-deficient cancers including, but not limited to, LAM.
Asunto(s)
Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Proteína 2 del Complejo de la Esclerosis Tuberosa/deficiencia , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridazinas , Quinolinas/farmacología , Sirolimus/farmacología , Sulfonamidas/farmacologíaRESUMEN
Lymphangioleiomyomatosis (LAM) is a rare, almost exclusively female lung disease linked to inactivating mutations in tuberous sclerosis complex 2 (TSC2), a tumor suppressor gene that controls cell metabolic state and growth via regulation of the mechanistic target of rapamycin (mTORC1) signaling. mTORC1 is frequently activated in human cancers and, although the mTORC1 inhibitor rapamycin has a cytostatic effect, it is, in general, unable to elicit a robust curative effect or tumor regression. Using RNA-Seq, we identified (1) Insulin-like Growth Factor (IGF2) as one of the genes with the highest fold-change difference between human TSC2-null and TSC2-expressing angiomyolipoma cells from a patient with LAM, and (2) the mouse IGF2 homolog Igf2, as a top-ranking gene according to fold change between Tsc2-/- and Tsc2+/+ mouse embryo fibroblasts (MEFs). We extended transcript-level findings to protein level, observing increased Igf2 protein expression and Igf2 secretion by Tsc2-/- MEFs. Increased Igf2 expression was not due to epigenetic imprinting, but was partially mediated through the Stat3 pathway and was completely insensitive to rapamycin treatment. An siRNA-mediated decrease of Igf2 resulted in decreased Stat3 phosphorylation, suggesting presence of an autocrine Igf2/Stat3 amplification cycle in Tsc2-/- MEFs. In human pulmonary LAM lesions and metastatic cell clusters, high levels of IGF2 were associated with mTORC1 activation. In addition, treatment of three primary IGF2-expressing LAM lung cell lines with rapamycin did not result in IGF2 level changes. Thus, targeting of IGF2 signaling may be of therapeutic value to LAM patients, particularly those who are unresponsive to rapamycin.
Asunto(s)
Embrión de Mamíferos/metabolismo , Fibroblastos/metabolismo , Regulación Neoplásica de la Expresión Génica , Factor II del Crecimiento Similar a la Insulina/biosíntesis , Neoplasias Pulmonares/metabolismo , Transducción de Señal , Sirolimus/farmacología , Proteínas Supresoras de Tumor/deficiencia , Animales , Línea Celular Tumoral , Embrión de Mamíferos/patología , Fibroblastos/patología , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Linfangioleiomiomatosis , Ratones , Ratones Noqueados , Proteína 2 del Complejo de la Esclerosis TuberosaRESUMEN
LOXL2 catalyzes the oxidative deamination of ε-amines of lysine and hydroxylysine residues within collagen and elastin, generating reactive aldehydes (allysine). Condensation with other allysines or lysines drives the formation of inter- and intramolecular cross-linkages, a process critical for the remodeling of the ECM. Dysregulation of this process can lead to fibrosis, and LOXL2 is known to be upregulated in fibrotic tissue. Small-molecules that directly inhibit LOXL2 catalytic activity represent a useful option for the treatment of fibrosis. Herein, we describe optimization of an initial hit 2, resulting in identification of racemic-trans-(3-((4-(aminomethyl)-6-(trifluoromethyl)pyridin-2-yl)oxy)phenyl)(3-fluoro-4-hydroxypyrrolidin-1-yl)methanone 28, a potent irreversible inhibitor of LOXL2 that is highly selective over LOX and other amine oxidases. Oral administration of 28 significantly reduced fibrosis in a 14-day mouse lung bleomycin model. The (R,R)-enantiomer 43 (PAT-1251) was selected as the clinical compound which has progressed into healthy volunteer Phase 1 trials, making it the "first-in-class" small-molecule LOXL2 inhibitor to enter clinical development.
Asunto(s)
Aminoácido Oxidorreductasas/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Piridinas/química , Piridinas/farmacología , Administración Oral , Aminoácido Oxidorreductasas/metabolismo , Animales , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/uso terapéutico , Fibrosis , Halogenación , Humanos , Pulmón/efectos de los fármacos , Pulmón/enzimología , Pulmón/patología , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/enzimología , Enfermedades Pulmonares/patología , Masculino , Metilación , Ratones Endogámicos C57BL , Modelos Moleculares , Piridinas/administración & dosificación , Piridinas/uso terapéutico , Relación Estructura-ActividadRESUMEN
Two series of novel LOXL2 enzyme inhibitors are described: benzylamines substituted with electron withdrawing groups at the para-position and 2-substituted pyridine-4-ylmethanamines. The most potent compound, (2-chloropyridin-4-yl)methanamine 20 (hLOXL2 IC50 = 126 nM), was shown to be selective for LOXL2 over LOX and three other amine oxidases (MAO-A, MAO-B, and SSAO). Compound 20 is the first published small molecule inhibitor selective for LOXL2 over LOX.
RESUMEN
Autotaxin (ATX) is a secreted glycoprotein that converts lysophosphatidylcholine (LPC) to the bioactive phospholipid lysophosphatidic acid (LPA) and is the major enzyme generating circulating LPA. Inhibition of LPA signaling has profound antifibrotic effects in multiple organ systems, including lung, kidney, skin, and peritoneum. However, other LPA-generating pathways exist, and the role of ATX in localized tissue LPA production and fibrosis remains unclear and controversial. In this study, we describe the preclinical pharmacologic, pharmacokinetic, and pharmacodynamic properties of a novel small-molecule ATX inhibitor, PAT-505 [3-((6-chloro-2-cyclopropyl-1-(1-ethyl-1H-pyrazol-4-yl)-7-fluoro-1H-indol-3-yl) thio)-2-fluorobenzoic acid sodium salt]. PAT-505 is a potent, selective, noncompetitive inhibitor that displays significant inhibition of ATX activity in plasma and liver tissue after oral administration. When dosed therapeutically in a Stelic Mouse Animal Model of nonalcoholic steatohepatitis (NASH), PAT-505 treatment resulted in a small but significant improvement in fibrosis with only minor improvements in hepatocellular ballooning and hepatic inflammation. In a choline-deficient, high-fat diet model of NASH, therapeutic treatment with PAT-505 robustly reduced liver fibrosis with no significant effect on steatosis, hepatocellular ballooning, or inflammation. These data demonstrate that inhibiting autotaxin is antifibrotic and may represent a novel therapeutic approach for the treatment of multiple fibrotic liver diseases, including NASH.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/enzimología , Hidrolasas Diéster Fosfóricas/metabolismo , Piperazinas/farmacología , Animales , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/uso terapéutico , Femenino , Humanos , Masculino , Ratones , Piperazinas/farmacocinética , Piperazinas/uso terapéuticoRESUMEN
Autotaxin (ATX) is a 125-kD type II ectonucleotide pyrophosphatase/phosphodiesterase (ENPP2 or NPP2) originally discovered as an unknown "autocrine motility factor" in human melanoma cells. In addition to its pyrophosphatase/phosphodiesterase activities ATX has lysophospholipase D (lysoPLD) activity, catalyzing the conversion of lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA). ATX is the only ENPP family member with lysoPLD activity and it produces most of the LPA in circulation. In support of this, ATX heterozygous mice have 50% of normal LPA plasma levels. The ATX-LPA signaling axis plays an important role in both normal physiology and disease pathogenesis and recently has been linked to pruritus in chronic cholestatic liver diseases, including primary biliary cholangitis (PBC). Several lines of evidence have suggested that a circulating puritogen is responsible, but the identification of the molecule has yet to be definitively identified. In contrast, plasma ATX activity is strongly associated with pruritus in PBC, suggesting a targetable molecule for treatment. We review herein the biochemistry of ATX and the rationale for its role in pruritus.
Asunto(s)
Colangitis/patología , Lisofosfolípidos/biosíntesis , Hidrolasas Diéster Fosfóricas/metabolismo , Prurito/metabolismo , Animales , Vías Biosintéticas , Humanos , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/genéticaRESUMEN
Autotaxin (ATX) is a secreted enzyme that hydrolyzes lysophosphatidylcholine to lysophosphatidic acid (LPA). LPA is a bioactive phospholipid that regulates diverse biological processes, including cell proliferation, migration, and survival/apoptosis, through the activation of a family of G protein-coupled receptors. The ATX-LPA pathway has been implicated in many pathologic conditions, including cancer, fibrosis, inflammation, cholestatic pruritus, and pain. Therefore, ATX inhibitors represent an attractive strategy for the development of therapeutics to treat a variety of diseases. Mouse and rat ATX have been crystallized previously with LPA or small-molecule inhibitors bound. Here, we present the crystal structures of human ATX in complex with four previously unpublished, structurally distinct ATX inhibitors. We demonstrate that the mechanism of inhibition of each compound reflects its unique interactions with human ATX. Our studies may provide a basis for the rational design of novel ATX inhibitors.
Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/metabolismo , Animales , Línea Celular Tumoral , Cristalización , Células HEK293 , Humanos , Ratones , Unión Proteica/fisiología , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Relación Estructura-ActividadRESUMEN
The endogenous ligands for the LT, lipoxin (LX) and oxoeicosanoid receptors are bioactive products produced by the action of the lipoxygenase family of enzymes. The LT receptors BLT1 and BLT2 , are activated by LTB4 and the CysLT1 and CysLT2 receptors are activated by the cysteinyl-LTs, whereas oxoeicosanoids exert their action through the OXE receptor. In contrast to these pro-inflammatory mediators, LXA4 transduces responses associated with the resolution of inflammation through the receptor FPR2/ALX (ALX/FPR2). The aim of the present review is to give a state of the field on these receptors, with focus on recent important findings. For example, BLT1 receptor signalling in cancer and the dual role of the BLT2 receptor in pro- and anti-inflammatory actions have added more complexity to lipid mediator signalling. Furthermore, a cross-talk between the CysLT and P2Y receptor systems has been described, and also the presence of novel receptors for cysteinyl-LTs, such as GPR17 and GPR99. Finally, lipoxygenase metabolites derived from ω-3 essential polyunsaturated acids, the resolvins, activate the receptors GPR32 and ChemR23. In conclusion, the receptors for the lipoxygenase products make up a sophisticated and tightly controlled system of endogenous pro- and anti-inflammatory signalling in physiology and pathology.
Asunto(s)
Receptores Eicosanoides/metabolismo , Animales , Humanos , Ligandos , Receptores Eicosanoides/agonistas , Receptores Eicosanoides/antagonistas & inhibidores , Transducción de SeñalRESUMEN
AIM: To assess the pharmacokinetics, pharmacodynamics, safety and tolerability of the 5-lipoxygenase-activating protein inhibitor, GSK2190915, after oral dosing in two independent phase I studies, one in Western European and one in Japanese subjects, utilizing different formulations. METHOD: Western European subjects received single (50-1000 mg) or multiple (10-450 mg) oral doses of GSK2190915 or placebo in a dose-escalating manner. Japanese subjects received three of four GSK2190915 doses (10-200 mg) plus placebo once in a four period crossover design. Blood samples were collected for GSK2190915 concentrations and blood and urine were collected to measure leukotriene B4 and leukotriene E4, respectively, as pharmacodynamic markers of drug activity. RESULTS: There was no clear difference in adverse events between placebo and active drug-treated subjects in either study. Maximum plasma concentrations of GSK2190915 and area under the curve increased in a dose-related manner and mean half-life values ranged from 16-34 h. Dose-dependent inhibition of blood leukotriene B4 production was observed and near complete inhibition of urinary leukotriene E4 excretion was shown at all doses except the lowest dose. The EC50 values for inhibition of LTB4 were 85 nM and 89 nM in the Western European and Japanese studies, respectively. CONCLUSION: GSK2190915 is well-tolerated with pharmacokinetics and pharmacodynamics in Western European and Japanese subjects that support once daily dosing for 24 h inhibition of leukotrienes. Doses of ≥50 mg show near complete inhibition of urinary leukotriene E4 at 24 h post-dose, whereas doses of ≥150 mg are required for 24 h inhibition of blood LTB4.
Asunto(s)
Inhibidores de Proteína Activante de 5-Lipoxigenasa , Indoles , Leucotrieno E4/sangre , Ácidos Pentanoicos , Inhibidores de Proteína Activante de 5-Lipoxigenasa/efectos adversos , Inhibidores de Proteína Activante de 5-Lipoxigenasa/farmacocinética , Inhibidores de Proteína Activante de 5-Lipoxigenasa/farmacología , Administración Oral , Adolescente , Adulto , Anciano , Área Bajo la Curva , Pueblo Asiatico , Biomarcadores/sangre , Biomarcadores/orina , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Indoles/efectos adversos , Indoles/farmacocinética , Indoles/farmacología , Leucotrieno B4/sangre , Leucotrieno B4/orina , Leucotrieno E4/orina , Masculino , Persona de Mediana Edad , Ácidos Pentanoicos/efectos adversos , Ácidos Pentanoicos/farmacocinética , Ácidos Pentanoicos/farmacología , Población Blanca , Adulto JovenRESUMEN
BACKGROUND: Cysteinyl leukotriene 1 (CysLT1) receptor expression is known to be increased in the airway mucosa of patients with asthma, especially during exacerbations; however, nothing is known of its expression in COPD. METHODS: We applied immunohistochemistry and in situ hybridization to endobronchial biopsies to determine inflammatory cell CysLT1 receptor protein and mRNA expression in the following: (1) 15 nonsmoker control subjects (NSC), (2) 16 smokers with moderate to severe COPD in its stable phase (S-COPD), and (3) 15 smokers with COPD hospitalized for a severe exacerbation (SE-COPD). RESULTS: The total number of bronchial mucosal inflammatory cells (CD45+) and those expressing CysLT1 receptor protein were significantly greater in SE-COPD (CysLT1 receptor protein: median [range] = 139 [31-634]) as compared with S-COPD (32 [6-114]) or NSC (16 [4-66]) (P < .001 for both). CysLT1 receptor gene expression showed similar differences. A greater proportion of CD451 cells expressed CysLT1 receptor protein in SE-COPD (median [range] = 22% [8-81]) compared with S-COPD (10% [4-32]) (P < .03) or NSC (7% [1-19]) (P < .002). In SE-COPD, the relative frequencies of CysLT1 receptor-expressing cells were as follows: tryptase1 mast cells > CD681 monocytes/macrophage > neutrophils > CD201 B lymphocytes = EG21 eosinophils. Moreover, there were positive correlations between the numbers of cells expressing CysLT1 receptor protein and the numbers of CD451 cells (r = 0.78; P < .003) and tryptase1 mast cells (r = 0.62; P < .02). CONCLUSIONS: Bronchial mucosal CysLT1 receptor-positive inflammatory cells are present in the bronchial mucosa in COPD in greatest number in those experiencing a severe exacerbation.
Asunto(s)
Bronquios/patología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/patología , ARN Mensajero/metabolismo , Receptores de Leucotrienos/genética , Receptores de Leucotrienos/metabolismo , Adulto , Anciano , Bronquios/metabolismo , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/etiología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Fumar/genética , Fumar/metabolismo , Fumar/patologíaRESUMEN
BACKGROUND: Allergic conjunctivitis is characterized by itchy, watery and swollen eyes which occur in response to exposure to seasonal or environmental allergens. The early phase reaction of allergic conjunctivitis is primarily mediated by mast cell degranulation while the late phase reaction is driven by Th2 cells and eosinophils. Prostaglandin D(2) (PGD(2)), released from mast cells, is present in allergic conjunctival tears and may elicit classical allergic responses via interaction with the high-affinity DP2 receptor (chemoattractant receptor-homologous molecule expressed on Th2 cells, CRTh2). Furthermore, antagonism of this receptor is well known to inhibit eosinophil chemotaxis, basophil activation and Th2 cytokine production. PGD(2), therefore, may be involved in both early and late phase reactions in response to allergen challenge. METHODS: Thus, we explored whether our novel and selective DP2 antagonist AM156 would be efficacious in animal models of allergic conjunctivitis. Furthermore, as respiratory syncytial virus (RSV) has been implicated in the pathogenesis of allergic conjunctivitis, we examined the effects of DP2 antagonism in a murine model of RSV ocular infection. RESULTS: Utilizing a guinea pig ovalbumin model and a murine ragweed model we demonstrated that AM156 reduces redness, discharge and swelling in response to allergen challenge. These effects were equal to or greater than those of current clinical treatment options for allergic conjunctivitis including topical corticosteroids and a dual-mechanism antihistamine and decongestant. AM156 significantly reduced RSV-induced ocular inflammation and IL-4 production. CONCLUSION: These results suggest that a topical DP2 antagonist such as AM156 may represent a novel therapeutic for allergic conjunctivitis.
Asunto(s)
Antialérgicos/uso terapéutico , Bencilaminas/uso terapéutico , Conjuntivitis Alérgica/tratamiento farmacológico , Conjuntivitis Viral/tratamiento farmacológico , Receptores Inmunológicos/antagonistas & inhibidores , Receptores de Prostaglandina/antagonistas & inhibidores , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Administración Tópica , Alérgenos/inmunología , Ambrosia/inmunología , Animales , Conjuntivitis Alérgica/inmunología , Conjuntivitis Alérgica/metabolismo , Conjuntivitis Viral/inmunología , Conjuntivitis Viral/metabolismo , Modelos Animales de Enfermedad , Femenino , Cobayas , Interleucina-4/inmunología , Interleucina-4/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Receptores Inmunológicos/inmunología , Receptores de Prostaglandina/inmunología , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/metabolismoRESUMEN
The potent 5-lipoxygenase-activating protein (FLAP) inhibitor 3-[3-tert-butylsulfanyl-1-[4-(6-ethoxypyridin-3-yl)benzyl]-5-(5-methylpyridin-2-ylmethoxy)-1H-indol-2-yl]-2,2-dimethylpropionic acid 11cc is described (AM803, now GSK2190915). Building upon AM103 (1) (Hutchinson et al. J. Med Chem.2009, 52, 5803-5815; Stock et al. Bioorg. Med. Chem. Lett. 2010, 20, 213-217; Stock et al. Bioorg. Med. Chem. Lett.2010, 20, 4598-4601), SAR studies centering around the pyridine moiety led to the discovery of compounds that exhibit significantly increased potency in a human whole blood assay measuring LTB(4) inhibition with longer drug preincubation times (15 min vs 5 h). Further studies identified 11cc with a potency of 2.9 nM in FLAP binding, an IC(50) of 76 nM for inhibition of LTB(4) in human blood (5 h incubation) and excellent preclinical toxicology and pharmacokinetics in rat and dog. 11cc also demonstrated an extended pharmacodynamic effect in a rodent bronchoalveolar lavage (BAL) model. This compound has successfully completed phase 1 clinical studies in healthy volunteers and is currently undergoing phase 2 trials in asthmatic patients.
Asunto(s)
Inhibidores de Proteína Activante de 5-Lipoxigenasa/síntesis química , Antiasmáticos/síntesis química , Indoles/síntesis química , Ácidos Pentanoicos/síntesis química , Inhibidores de Proteína Activante de 5-Lipoxigenasa/farmacocinética , Inhibidores de Proteína Activante de 5-Lipoxigenasa/farmacología , Administración Oral , Animales , Antiasmáticos/farmacocinética , Antiasmáticos/farmacología , Lavado Broncoalveolar , Inhibidores Enzimáticos del Citocromo P-450 , Perros , Femenino , Humanos , Técnicas In Vitro , Indoles/farmacocinética , Indoles/farmacología , Masculino , Ácidos Pentanoicos/farmacocinética , Ácidos Pentanoicos/farmacología , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
Biphenylacetic acid (5) was identified through a library screen as an inhibitor of the prostaglandin D(2) receptor DP2 (CRTH2). Optimization for potency and pharmacokinetic properties led to a series of selective CRTH2 antagonists. Compounds demonstrated potency in a human DP2 binding assay and a human whole blood eosinophil shape change assay, as well as good oral bioavailability in rat and dog, and efficacy in a mouse model of allergic rhinitis following oral dosing.
Asunto(s)
Modelos Animales de Enfermedad , Descubrimiento de Drogas , Fenilacetatos/farmacología , Receptores Inmunológicos/antagonistas & inhibidores , Receptores de Prostaglandina/antagonistas & inhibidores , Rinitis Alérgica Perenne/tratamiento farmacológico , Animales , Disponibilidad Biológica , Perros , Ratones , Fenilacetatos/química , Fenilacetatos/farmacocinética , Fenilacetatos/uso terapéutico , RatasRESUMEN
The seven-transmembrane G protein-coupled receptors activated by leukotrienes are divided into two subclasses based on their ligand specificity for either leukotriene B(4) or the cysteinyl leukotrienes (LTC(4), LTD(4), and LTE(4)). These receptors have been designated BLT and CysLT receptors, respectively, and a subdivision into BLT(1) and BLT(2) receptors and CysLT(1) and CysLT(2) receptors has been established. However, recent findings have also indicated the existence of putative additional leukotriene receptor subtypes. Furthermore, other ligands interact with the leukotriene receptors. Finally, leukotrienes may also activate other receptor classes, such as purinergic receptors. The aim of this review is to provide an update on the pharmacology, expression patterns, and pathophysiological roles of the leukotriene receptors as well as the therapeutic developments in this area of research.
Asunto(s)
Regulación de la Expresión Génica , Receptores de Leucotrienos/clasificación , Animales , Cisteína/agonistas , Cisteína/antagonistas & inhibidores , Cisteína/metabolismo , Humanos , Agencias Internacionales , Antagonistas de Leucotrieno/uso terapéutico , Leucotrienos/agonistas , Leucotrienos/metabolismo , Terapia Molecular Dirigida , Especificidad de Órganos , Receptores de Leucotrienos/química , Receptores de Leucotrienos/genética , Receptores de Leucotrienos/metabolismo , Transducción de Señal/efectos de los fármacos , Terminología como AsuntoRESUMEN
The prostaglandin D(2) (PGD(2)) receptor type 2 (DP2) is a G protein-coupled receptor that has been shown to be involved in a variety of allergic diseases, including allergic rhinitis, asthma, and atopic dermatitis. In this study, we describe the preclinical pharmacological and pharmacokinetic properties of the small-molecule DP2 antagonist [2'-(3-benzyl-1-ethyl-ureidomethyl)-6-methoxy-4'-trifluoromethyl-biphenyl-3-yl]-acetic acid (AM211). We determine that AM211 has high affinity for human, mouse, rat, and guinea pig DP2 and it shows selectivity over other prostanoid receptors and enzymes. Antagonist activity of AM211 at the DP2 receptor was confirmed by inhibition of PGD(2)-stimulated guanosine 5'-O-[γ-thio]triphosphate binding to membranes expressing human DP2. A basophil activation assay and a whole-blood assay of eosinophil shape change were used to demonstrate the ability of AM211 to potently antagonize PGD(2)-stimulated functional responses in relevant human cells and in the context of a physiologically relevant environment. AM211 exhibits good oral bioavailability in rats and dogs and dose-dependently inhibits 13,14-dihydro-15-keto-PGD(2)-induced leukocytosis in a guinea pig pharmacodynamic assay. AM211 demonstrates efficacy in two animal models of allergic inflammation, including an ovalbumin-induced lung inflammation model in guinea pigs and an ovalbumin-induced mouse model of allergic rhinitis. AM211 represents a potent and selective antagonist of DP2 that may be used clinically to evaluate the role of DP2 in T helper 2-driven allergic inflammatory diseases.
Asunto(s)
Modelos Animales de Enfermedad , Compuestos de Metilurea/uso terapéutico , Fenilacetatos/uso terapéutico , Antagonistas de Prostaglandina/uso terapéutico , Receptores Inmunológicos/antagonistas & inhibidores , Receptores de Prostaglandina/antagonistas & inhibidores , Rinitis Alérgica Perenne/tratamiento farmacológico , Adulto , Animales , Perros , Femenino , Cobayas , Células HEK293 , Humanos , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Masculino , Compuestos de Metilurea/química , Compuestos de Metilurea/farmacología , Ratones , Ratones Endogámicos BALB C , Fenilacetatos/química , Fenilacetatos/farmacología , Neumonía/tratamiento farmacológico , Neumonía/inmunología , Neumonía/metabolismo , Antagonistas de Prostaglandina/química , Antagonistas de Prostaglandina/farmacología , Unión Proteica/fisiología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Receptores Inmunológicos/inmunología , Receptores Inmunológicos/metabolismo , Receptores de Prostaglandina/inmunología , Receptores de Prostaglandina/metabolismo , Rinitis Alérgica Perenne/inmunología , Rinitis Alérgica Perenne/metabolismoRESUMEN
Compound 21 (AM432) was identified as a potent and selective antagonist of the DP(2) receptor (CRTH2). Modification of a bi-aryl core identified a series of tri-aryl antagonists of which compound 21 proved a viable clinical candidate. AM432 shows excellent potency in a human whole blood eosinophil shape change assay with prolonged incubation, a comparatively long off-rate from the DP(2) receptor, excellent pharmacokinetics in dog and in vivo activity in two mouse models of inflammatory disease after oral dosing.
Asunto(s)
Fenilacetatos/química , Piridinas/química , Receptores Inmunológicos/antagonistas & inhibidores , Receptores de Prostaglandina/antagonistas & inhibidores , Administración Oral , Animales , Modelos Animales de Enfermedad , Perros , Eosinófilos/efectos de los fármacos , Eosinófilos/inmunología , Humanos , Inflamación/tratamiento farmacológico , Ratones , Fenilacetatos/farmacocinética , Fenilacetatos/uso terapéutico , Piridinas/farmacocinética , Piridinas/uso terapéutico , Receptores Inmunológicos/metabolismo , Receptores de Prostaglandina/metabolismoRESUMEN
We evaluated the in vivo pharmacological properties of AM803 3-[3-tert-butylsulfanyl-1-[4-(6-ethoxy-pyridin-3-yl)-benzyl]-5-(5-methyl-pyridin-2-ylmethoxy)-1H-indol-2-yl]-2,2-dimethyl-propionic acid, a selective five-lipoxygenase-activating protein (FLAP) inhibitor, using rat and mouse models of acute inflammation. Oral administration of AM803 (1 mg/kg) resulted in sustained inhibition of ex vivo ionophore-challenged whole blood LTB4 biosynthesis with >90% inhibition for up to 12 h and an EC50 of approximately 7 nM. When rat lungs were challenged in vivo with calcium-ionophore, AM803 inhibited LTB4 and cysteinyl leukotriene (CysLT) production with ED50s of 0.12 mg/kg and 0.37 mg/kg, respectively. The inhibition measured 16 h following a single oral dose of 3 mg/kg was 86% and 41% for LTB4 and CysLTs, respectively. In an acute inflammation setting, AM803 dose-dependently reduced LTB4, CysLTs, plasma protein extravasation and neutrophil influx induced by peritoneal zymosan injection. Finally, AM803 increased survival time in mice exposed to a lethal intravenous injection of platelet activating factor (PAF). The magnitude of effect was similar to that of an inhibitor of five-lipoxygenase (5-LO) and LTA4 hydrolase but superior to a leukotriene CysLT1 receptor antagonist. In summary, AM803 is a novel, potent and selective FLAP inhibitor that has excellent pharmacodynamic properties in vivo and is effective in animal models of acute inflammation and in a model of lethal shock.