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An open-label, single-center, phase I study was conducted to determine the absolute bioavailability and absorption, distribution, metabolism, and excretion of capivasertib-a potent, selective AKT serine/threonine kinase inhibitor-in healthy males. In part 1, six participants received a single oral dose of capivasertib (400 mg; tablets) followed by a [14C]-radiolabeled intravenous microdose of capivasertib (100 µg). After a 14-day washout, five of the participants proceeded to part 2 and received a single oral dose of [14C]capivasertib (400 mg; solution). In part 1, median time of maximum observed concentration for capivasertib was 1.7 hours, geometric mean terminal elimination half-life was 12.9 hours, and absolute bioavailability was estimated at 28.6% (90% confidence interval, 23.9 to 34.2). In part 2, a high proportion of the administered radioactivity was recovered over the 168-hour sampling period [mean recovery: 95.1% (feces, 50.4%; urine, 44.7%)]. Unchanged capivasertib in urine accounted for 7.4% of the total dose and 21.1% of the systemically available drug. Geometric mean renal clearance was 8.3 L/h, suggesting active tubular secretion. Twelve metabolites were identified in plasma. M11 (AZ14102143)-the glucuronide conjugate of capivasertib, inactive as an AKT serine/threonine kinase inhibitor-was the most abundant, accounting for a mean 78.4% of the plasma drug-related area under the curve. Of 22 metabolites identified in excreta, M11 was the most abundant (mean 28.2% of administered dose), indicating direct glucuronidation as one of the major routes of metabolism. No new safety concerns were identified. SIGNIFICANCE STATEMENT: This study provides characterization of the pharmacokinetics of capivasertib-a potent, selective AKT serine/threonine kinase (AKT) inhibitor-including absolute bioavailability, mass balance, and metabolic fate in humans; the findings are being used to inform further clinical development. Absolute bioavailability was estimated at 28.6%, and mean recovery of the administered dose in excreta over 168 hours was 95.1%. M11 (AZ14102143)-the glucuronide conjugate, inactive as an AKT inhibitor-was the most abundant identified metabolite in plasma and excreta.
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Disponibilidad Biológica , Voluntarios Sanos , Humanos , Masculino , Adulto , Adulto Joven , Administración Oral , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/sangre , Distribución Tisular , Pirroles/farmacocinética , Pirroles/administración & dosificación , Pirroles/metabolismo , Pirroles/orina , Pirroles/sangre , Persona de Mediana Edad , Semivida , Heces/química , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Pirimidinas/farmacocinética , Pirimidinas/sangre , Pirimidinas/administración & dosificaciónRESUMEN
Scientific innovation is overturning conventional paradigms of forest, water, and energy cycle interactions. This has implications for our understanding of the principal causal pathways by which tree, forest, and vegetation cover (TFVC) influence local and global warming/cooling. Many identify surface albedo and carbon sequestration as the principal causal pathways by which TFVC affects global warming/cooling. Moving toward the outer latitudes, in particular, where snow cover is more important, surface albedo effects are perceived to overpower carbon sequestration. By raising surface albedo, deforestation is thus predicted to lead to surface cooling, while increasing forest cover is assumed to result in warming. Observational data, however, generally support the opposite conclusion, suggesting surface albedo is poorly understood. Most accept that surface temperatures are influenced by the interplay of surface albedo, incoming shortwave (SW) radiation, and the partitioning of the remaining, post-albedo, SW radiation into latent and sensible heat. However, the extent to which the avoidance of sensible heat formation is first and foremost mediated by the presence (absence) of water and TFVC is not well understood. TFVC both mediates the availability of water on the land surface and drives the potential for latent heat production (evapotranspiration, ET). While latent heat is more directly linked to local than global cooling/warming, it is driven by photosynthesis and carbon sequestration and powers additional cloud formation and top-of-cloud reflectivity, both of which drive global cooling. TFVC loss reduces water storage, precipitation recycling, and downwind rainfall potential, thus driving the reduction of both ET (latent heat) and cloud formation. By reducing latent heat, cloud formation, and precipitation, deforestation thus powers warming (sensible heat formation), which further diminishes TFVC growth (carbon sequestration). Large-scale tree and forest restoration could, therefore, contribute significantly to both global and surface temperature cooling through the principal causal pathways of carbon sequestration and cloud formation.
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Secuestro de Carbono , Cambio Climático , Bosques , Planetas , Temperatura , Agua , Frío , ÁrbolesRESUMEN
Although the effect of pollution on forest health and decline received much attention in the 1980s, it has not been considered to explain the 'Divergence Problem' in dendroclimatology; a decoupling of tree growth from rising air temperatures since the 1970s. Here we use physical and biogeochemical measurements of hundreds of living and dead conifers to reconstruct the impact of heavy industrialisation around Norilsk in northern Siberia. Moreover, we develop a forward model with surface irradiance forcing to quantify long-distance effects of anthropogenic emissions on the functioning and productivity of Siberia's taiga. Downwind from the world's most polluted Arctic region, tree mortality rates of up to 100% have destroyed 24,000 km2 boreal forest since the 1960s, coincident with dramatic increases in atmospheric sulphur, copper, and nickel concentrations. In addition to regional ecosystem devastation, we demonstrate how 'Arctic Dimming' can explain the circumpolar 'Divergence Problem', and discuss implications on the terrestrial carbon cycle.
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Ecosistema , Taiga , Regiones Árticas , Bosques , ÁrbolesRESUMEN
Individuals with the Bombay phenotype (Oh) in the ABO blood group system do not express the H, A, and B antigens but have no clinical symptoms. Bombay phenotype with clinical symptoms has been described in leukocyte adhesion deficiency type II (LAD II), a fucosylation disorder caused by mutations in SLC35C1. Only few LAD II patients have been described so far. Here we describe an additional patient, a 22-year old male, born to unrelated parents, presenting with inflammatory skin disease, periodontitis, growth, and mental retardation, admitted to the department of dentistry for treatment under general anesthesia. Pre-operative routine investigations revealed the presence of the Bombay phenotype (Oh). Genomic sequencing identified two novel triplet deletions of the SLC35C1 gene. Functional investigations confirmed the diagnosis of LAD II. Therapy with oral fucose led to the disappearance of the chronic skin infections and improvements in behavior and attention span.
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Síndrome de Deficiencia de Adhesión del Leucocito/diagnóstico , Sistema del Grupo Sanguíneo ABO , Adulto , Tipificación y Pruebas Cruzadas Sanguíneas , Eritrocitos , Fucosa/uso terapéutico , Humanos , Síndrome de Deficiencia de Adhesión del Leucocito/sangre , Síndrome de Deficiencia de Adhesión del Leucocito/tratamiento farmacológico , Síndrome de Deficiencia de Adhesión del Leucocito/genética , Leucocitos , Masculino , Proteínas de Transporte de Monosacáridos/genética , Adulto JovenRESUMEN
In recent years, many mutations have been identified that affect the biosynthesis of the glycosylphosphatidylinositol anchor, a biomolecule that attaches surface molecules to cell membranes. Here, we present two second-degree cousins with unexplained patterns of seizures. Next-generation sequencing identified the homozygous c.460A>G; p.(R154G) PIGW mutation in both patients. Transfection of the mutated allele into Pigw-defective CHO cells indicated impaired enzymatic activity of the mutated PIGW product. Alkaline phosphatase did not exceed the upper normal range and flow cytometry of CD16, CD24, and CD66c on granulocytes showed subtle changes of the cellular expression of the glycosylphosphatidylinositol-anchored proteins. The patients' phenotype is therefore remarkably different from the phenotype of the only other described individual with PIGW mutations. Patients might therefore be missed when relying on traditional flow cytometry of glycosylphosphatidylinositol-anchored proteins only and we suggest that glycosylphosphatidylinositol-deficiency should be considered even with patients not showing the typical clinical phenotypes. © 2016 Wiley Periodicals, Inc.
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Estudios de Asociación Genética , Glicosilfosfatidilinositoles/deficiencia , Manosiltransferasas/genética , Mutación , Fenotipo , Consanguinidad , Análisis Mutacional de ADN , Electroencefalografía , Femenino , Glicosilfosfatidilinositoles/genética , Homocigoto , Humanos , Lactante , Masculino , Examen Físico , ConvulsionesRESUMEN
Beyond its well-established roles in mediating leukocyte rolling, E-selectin is emerging as a multifunctional receptor capable of inducing integrin activation in neutrophils, and of regulating various biological processes in hematopoietic precursors. Although these effects suggest important homeostatic contributions of this selectin in the immune and hematologic systems, the ligands responsible for transducing these effects in different leukocyte lineages are not well defined. We have characterized mice deficient in E-selectin ligand-1 (ESL-1), or in both P-selectin glycoprotein-1 (PSGL-1) and ESL-1, to explore and compare the contributions of these glycoproteins in immune and hematopoietic cell trafficking. In the steady state, ESL-1 deficiency resulted in a moderate myeloid expansion that became more prominent when both glycoproteins were eliminated. During inflammation, PSGL-1 dominated E-selectin binding, rolling, integrin activation, and extravasation of mature neutrophils, but only the combined deficiency in PSGL-1 and ESL-1 completely abrogated leukocyte recruitment. Surprisingly, we find that the levels of ESL-1 were strongly elevated in hematopoietic progenitor cells. These elevations correlated with a prominent function of ESL-1 for E-selectin binding and for migration of hematopoietic progenitor cells into the bone marrow. Our results uncover dominant roles for ESL-1 in the immature compartment, and a functional shift toward PSGL-1 dependence in mature neutrophils.
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Células Madre Hematopoyéticas/inmunología , Inflamación/inmunología , Receptores de Factores de Crecimiento de Fibroblastos/inmunología , Sialoglicoproteínas/inmunología , Animales , Western Blotting , Médula Ósea/inmunología , Médula Ósea/metabolismo , Movimiento Celular/inmunología , Selectina E/metabolismo , Femenino , Citometría de Flujo , Células Madre Hematopoyéticas/metabolismo , Inflamación/genética , Inflamación/metabolismo , Rodamiento de Leucocito/genética , Rodamiento de Leucocito/inmunología , Leucocitos/inmunología , Leucocitos/metabolismo , Masculino , Glicoproteínas de Membrana/deficiencia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/inmunología , Neutrófilos/metabolismo , Peritonitis/genética , Peritonitis/inmunología , Peritonitis/metabolismo , Unión Proteica/inmunología , Receptores de Factores de Crecimiento de Fibroblastos/deficiencia , Receptores de Factores de Crecimiento de Fibroblastos/genética , Sialoglicoproteínas/deficiencia , Sialoglicoproteínas/genéticaRESUMEN
Plant photosynthesis tends to increase with irradiance. However, recent theoretical and observational studies have demonstrated that photosynthesis is also more efficient under diffuse light conditions. Changes in cloud cover or atmospheric aerosol loadings, arising from either volcanic or anthropogenic emissions, alter both the total photosynthetically active radiation reaching the surface and the fraction of this radiation that is diffuse, with uncertain overall effects on global plant productivity and the land carbon sink. Here we estimate the impact of variations in diffuse fraction on the land carbon sink using a global model modified to account for the effects of variations in both direct and diffuse radiation on canopy photosynthesis. We estimate that variations in diffuse fraction, associated largely with the 'global dimming' period, enhanced the land carbon sink by approximately one-quarter between 1960 and 1999. However, under a climate mitigation scenario for the twenty-first century in which sulphate aerosols decline before atmospheric CO(2) is stabilized, this 'diffuse-radiation' fertilization effect declines rapidly to near zero by the end of the twenty-first century.
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Atmósfera/química , Carbono/metabolismo , Oscuridad , Ecosistema , Fotosíntesis/efectos de la radiación , Plantas/efectos de la radiación , Luz Solar , Aerosoles/análisis , Aerosoles/química , Dióxido de Carbono/análisis , Efecto Invernadero , Historia del Siglo XX , Historia del Siglo XXI , Plantas/metabolismo , Sulfatos/metabolismo , Erupciones VolcánicasRESUMEN
The electrophilic nature of chalcones (1,3-diphenylprop-2-en-1-ones) and many other α,ß-unsaturated carbonyl compounds is crucial for their biological activity, which is often based on thiol-mediated regulation processes. To better predict their biological activity a simple screening assay for the assessment of the second-order rate constants (k(2)) in thia-Michael additions was developed. Hence, a clear structure-activity relationship of 16 differentially decorated hydroxy-alkoxychalcones upon addition of cysteamine could be established. Moreover, amongst other naturally occurring α,ß-unsaturated carbonyl compounds k(2) values for curcumin and cinnamaldehyde were gained while cinnamic acids or esters gave no or very slow reactions.
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Chalconas/química , Compuestos de Sulfhidrilo/química , CinéticaRESUMEN
As Earth's primary energy source, surface downward solar radiation (R s) determines the solar power potential and usage for climate change mitigation. Future projections of R s based on climate models have large uncertainties that interfere with the efficient deployment of solar energy to achieve China's carbon-neutrality goal. Here we assess 24 models in the latest Coupled Model Intercomparison Project Phase 6 with historical observations in China and find systematic biases in simulating historical R s values likely due to model biases in cloud cover and clear-sky radiation, resulting in largely uncertain projections for future changes in R s. Based on emergent constraints, we obtain credible R s with narrowed uncertainties by â¼56% in the mid-twenty-first century and show that the mean R s change during 2050-2069 relative to 1995-2014 is 30% more brightening than the raw projections. Particularly in North China and Southeast China with higher power demand, the constrained projections present more significant brightening, highlighting the importance of considering the spatial changes in future Rs when locating new solar energy infrastructures.
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This white paper summarizes the recommendations of the absorption, distribution, metabolism, and excretion (ADME) Subcommittee of the Oligonucleotide Safety Working Group for the characterization of absorption, distribution, metabolism, and excretion of oligonucleotide (ON) therapeutics in nonclinical studies. In general, the recommended approach is similar to that for small molecule drugs. However, some differences in timing and/or scope may be warranted due to the greater consistency of results across ON classes as compared with the diversity among small molecule classes. For some types of studies, a platform-based approach may be appropriate; once sufficient data are available for the platform, presentation of these data should be sufficient to support development of additional ONs of the same platform. These recommendations can serve as a starting point for nonclinical study design and foundation for discussions with regulatory agencies.
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Oligonucleótidos , Oligonucleótidos/uso terapéutico , Oligonucleótidos/farmacocinéticaRESUMEN
We describe a novel type of human thrombocytopenia characterized by the appearance of giant platelets and variable neutropenia. Searching for the molecular defect, we found that neutrophils had strongly reduced sialyl-Lewis X and increased Lewis X surface expression, pointing to a deficiency in sialylation. We show that the glycosylation defect is restricted to α2,3-sialylation and can be detected in platelets, neutrophils, and monocytes. Platelets exhibited a distorted structure of the open canalicular system, indicating defective platelet generation. Importantly, patient platelets, but not normal platelets, bound to the asialoglycoprotein receptor (ASGP-R), a liver cell-surface protein that removes desialylated thrombocytes from the circulation in mice. Taken together, this is the first type of human thrombocytopenia in which a specific defect of α2,3-sialylation and an induction of platelet binding to the liver ASGP-R could be detected.
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Ácido N-Acetilneuramínico/metabolismo , Oligosacáridos/metabolismo , Trombocitopenia/metabolismo , Trombocitopenia/patología , Animales , Receptor de Asialoglicoproteína/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Plaquetas/ultraestructura , Niño , Femenino , Granulocitos/metabolismo , Humanos , Interleucina-8/metabolismo , Hígado/metabolismo , Ratones , Mutación/genética , Neutropenia/complicaciones , Neutropenia/patología , Proteínas de Transporte de Nucleótidos/genética , Fenotipo , Unión Proteica , Selectinas/metabolismo , Antígeno Sialil Lewis X , Trombocitopenia/complicacionesRESUMEN
von Willebrand factor (VWF) is an important player in hemostasis but has also been suggested to promote inflammatory processes. Gene ablation of VWF causes a simultaneous defect in P-selectin expression making it difficult to identify VWF-specific functions. Therefore, we analyzed whether blocking antibodies against VWF would be able to interfere with neutrophil extravasation. We found that these antibodies inhibited neutrophil recruitment into thioglycollate-inflamed peritoneum and KC-stimulated cremaster by approximately 50%. Whereas platelet-VWF was not involved, the contribution of VWF to granulocyte recruitment was strictly dependent on the presence of platelets and the accessibility of their VWF-receptor glycoprotein Ib. Surprisingly, platelet P-selectin was largely dispensable for leukocyte extravasation, in agreement with our observation that anti-VWF antibodies did not affect leukocyte rolling and adhesion. Searching for possible effects downstream of leukocyte capture, we found that anti-VWF antibodies significantly inhibited thioglycollate-induced vascular permeability. The increase of permeability was independent of circulating granulocytes, showing that it was not a side effect of neutrophil diapedesis. Collectively, our results demonstrate that VWF-associated platelets strongly support neutrophil extravasation at a step downstream of leukocyte docking to the vessel wall. This step could be related to leukocyte diapedesis facilitated by destabilization of the endothelial barrier.
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Movimiento Celular , Leucocitos/citología , Leucocitos/inmunología , Peritonitis/inmunología , Factor de von Willebrand/inmunología , Animales , Anticuerpos/inmunología , Plaquetas/inmunología , Permeabilidad Capilar , Ratones , Ratones Endogámicos C57BL , Neutrófilos/citología , Neutrófilos/inmunología , Selectina-P/inmunología , Peritoneo/inmunología , Complejo GPIb-IX de Glicoproteína Plaquetaria/inmunologíaRESUMEN
Drug reactivity and bioactivation are of major concern to the development of potential drug candidates in the pharmaceutical industry (Chem Res Toxicol 17:3-16, 2004; Chem Res Toxicol 19:889-893, 2006). Identifying potentially problematic compounds as soon as possible in the discovery process is of great importance, so often early in vitro screening is used to speed up attrition. Identification of reactive moieties is relatively straightforward with appropriate in vitro trapping experiments; however, on occasion unexpected reactive intermediates can be found later during more detailed in vivo studies. Here, we present one such example involving a series of compounds from an early drug discovery campaign. These compounds were found to react with endogenous formaldehyde from a rat in vivo study, resulting in the formation of novel +13-Da bridged homopiperazine products (equivalent to the addition of one carbon and one hydrogen atom), which were detected in urine and blood. The identification of these +13-Da products and their origin and mechanism of formation are described in detail through analyses of a representative homopiperazine compound [N-(3-(3-fluorophenyl)-1,2,4-thiadiazol-5-yl)-4-(4-isopropyl-1,4-diaze-pane-2-carbonyl)piperazine-1-carboxamide (AZX)] by liquid chromatography-UV-mass spectrometry, (1)H NMR, and chemical tests.
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Formaldehído/metabolismo , Piperazinas/farmacología , Animales , Formaldehído/sangre , Formaldehído/orina , Espectroscopía de Resonancia Magnética , Piperazina , Piperazinas/metabolismo , RatasRESUMEN
Modifications to a series of potent and selective substituted 1-(3,3-diphenylpropyl)-piperidine phenylacetamide CCR5 antagonists were explored with the aim of reducing affinity at the hERG cardiac ion channel. Replacement of one aromatic ring in the diphenylpropyl region with less lipophilic, saturated heterocyclic rings and subsequent optimisation of the other phenyl ring led to the identification of clinical compound AZD5672 which retained excellent potency while reducing hERG affinity. Modulating lipophilicity affected the interplay between potency, hERG affinity and absorption. AZD5672 was found to have an acceptable balance of these properties and was progressed to a phase II clinical trial to test the hypothesis that inhibition of CCR5 will bring benefits in the treatment of rheumatoid arthritis.
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Artritis Reumatoide , Bencenoacetamidas/síntesis química , Antagonistas de los Receptores CCR5 , Descubrimiento de Drogas , Canales de Potasio Éter-A-Go-Go/metabolismo , Sulfonamidas/síntesis química , Absorción , Administración Oral , Artritis Reumatoide/tratamiento farmacológico , Bencenoacetamidas/administración & dosificación , Bencenoacetamidas/farmacología , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/química , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Unión Proteica/efectos de los fármacos , Receptores CCR5/metabolismo , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacologíaRESUMEN
Despite the importance of high-latitude surface energy budgets (SEBs) for land-climate interactions in the rapidly changing Arctic, uncertainties in their prediction persist. Here, we harmonize SEB observations across a network of vegetated and glaciated sites at circumpolar scale (1994-2021). Our variance-partitioning analysis identifies vegetation type as an important predictor for SEB-components during Arctic summer (June-August), compared to other SEB-drivers including climate, latitude and permafrost characteristics. Differences among vegetation types can be of similar magnitude as between vegetation and glacier surfaces and are especially high for summer sensible and latent heat fluxes. The timing of SEB-flux summer-regimes (when daily mean values exceed 0 Wm-2) relative to snow-free and -onset dates varies substantially depending on vegetation type, implying vegetation controls on snow-cover and SEB-flux seasonality. Our results indicate complex shifts in surface energy fluxes with land-cover transitions and a lengthening summer season, and highlight the potential for improving future Earth system models via a refined representation of Arctic vegetation types.
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Ecosistema , Hielos Perennes , Estaciones del Año , Regiones Árticas , Cambio ClimáticoRESUMEN
Syndecan-1 (Sdc1) plays a major role in wound healing and modulates inflammatory responses. Sdc1 expression is reduced in lesions of patients with ulcerative colitis. The aim of this study was to investigate the role of Sdc1 in murine dextran sodium sulfate (DSS)-induced colitis. DSS colitis was induced in Sdc1-deficient (knockout (KO)) and wild-type mice by oral administration of 3% DSS. KO mice exhibited a significantly increased lethality as compared with wild-type controls (61 versus 5%, P < 0.05). Impaired mucosal healing and prolonged recruitment of inflammatory cells in KO mice were accompanied by significant up-regulation of tumor necrosis factor-alpha, CC chemokine ligand 3/macrophage inflammatory protein-1alpha, and vascular cell adhesion molecule-1, as determined by histological correlation between 0 and 15 days after colitis induction, TaqMan low-density array analysis, and quantitative real-time PCR. Treatment from days 7 through 14 with enoxaparin, a functional analogue of the Sdc1 heparan sulfate chains, significantly reduced lethality of KO mice due to DSS-induced colitis, which was correlated with improved mucosal healing. In vitro, Sdc1-deficient polymorphonuclear cells displayed increased adhesion to endothelial cells and intercellular adhesion molecule-1, and enoxaparin reverted adhesion to wild-type levels. Small interfering RNA-mediated knockdown of Sdc1 expression resulted in reduced basic fibroblast growth factor-mediated mitogen-activated protein kinase signaling and reduced Caco-2 cell proliferation. We conclude that Sdc1 has a protective effect during experimental colitis. The modification of missing Sdc1 function by heparin analogues may emerge as a promising anti-inflammatory approach.
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Colitis/tratamiento farmacológico , Enoxaparina/uso terapéutico , Sindecano-1/deficiencia , Animales , Células CACO-2 , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Colitis/genética , Colitis/patología , Sulfato de Dextran , Factor 2 de Crecimiento de Fibroblastos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Inflamación/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Intestinos/efectos de los fármacos , Intestinos/patología , Tejido Linfoide/efectos de los fármacos , Tejido Linfoide/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , ARN Interferente Pequeño/metabolismo , Sindecano-1/genética , Sindecano-1/metabolismo , Cicatrización de Heridas/efectos de los fármacosRESUMEN
The cell surface heparan sulfate proteoglycan syndecan-1 (CD138) modulates the activity of chemokines, cytokines, integrins, and other adhesion molecules which play important roles in the regulation of inflammation. We have previously shown that syndecan-1-deficient murine leukocytes display increased interactions with endothelial cells and increased diapedesis in vivo and in vitro. In this study, we demonstrate that syndecan-1 has an important function as a negative modulator in the murine contact allergy model of oxazolone-mediated delayed-type hypersensitivity (DTH). Following elicitation of the DTH response, syndecan-1-deficient mice showed an increase in leukocyte recruitment, resulting in an increased and prolonged edema formation. Expression of the cytokines TNF-alpha and IL-6 of the chemokines CCL5/RANTES and CCL-3/MIP-1alpha and of the adhesion molecule ICAM-1 were significantly increased in syndecan-1-deficient compared with wild-type mice. In wild-type mice, syndecan-1 mRNA and protein expression was reduced during the DTH response. The differentially increased adhesion of syndecan-1-deficient leukocytes to ICAM-1 was efficiently inhibited in vitro by CD18-blocking Abs, which emerges as one mechanistic explanation for the anti-inflammatory effects of syndecan-1. Collectively, our results show an important role of syndecan-1 in the contact DTH reaction, identifying syndecan-1 as a novel target in anti-inflammatory therapy.
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Hipersensibilidad Tardía/inmunología , Sindecano-1/inmunología , Animales , Movimiento Celular/inmunología , Epítopos/inmunología , Heparitina Sulfato/inmunología , Hipersensibilidad Tardía/genética , Hipersensibilidad Tardía/metabolismo , Hipersensibilidad Tardía/patología , Molécula 1 de Adhesión Intercelular/metabolismo , Leucocitos/citología , Leucocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Regulación hacia ArribaRESUMEN
Selumetinib (ARRY-142886), an oral, potent and highly selective allosteric mitogen-activated protein kinase kinase 1/2 inhibitor, is approved by the US Food and Drug Administration for the treatment of pediatric patients aged ≥2 years with neurofibromatosis type 1 with symptomatic, inoperable plexiform neurofibromas. A physiologically based pharmacokinetic (PBPK) model was constructed to predict plasma concentration-time profiles of selumetinib, and to evaluate the impact of coadministering moderate cytochrome P450 (CYP) 3A4/2C19 inhibitors/inducers. The model was also used to extrapolate pharmacokinetic exposures from older children with different body surface area to guide dosing in younger children. This model was built based on physiochemical data and clinical in vivo drug-drug interaction (DDI) studies with itraconazole and fluconazole, and verified against data from an in vivo rifampicin DDI study and an absolute bioavailability study. The pediatric model was updated by changing system-specific input parameters using the Simcyp pediatric module. The model captured the observed selumetinib pharmacokinetic profiles and the interactions with CYP inhibitors/inducers. The predictions from the PBPK model showed a DDI effect of 30% to 40% increase or decrease in selumetinib exposure when coadministered with moderate CYP inhibitors or inducers, respectively, which was used to inform dose management and adjustments. The pediatric PBPK model was applied to simulate exposures in specific body surface area brackets that matched those achieved with a 25 mg/m2 dose in SPRINT clinical trials. The pediatric PBPK model was used to guide the dose for younger patients in a planned pediatric clinical study.
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Bencimidazoles/farmacocinética , Inductores de las Enzimas del Citocromo P-450/farmacología , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Inhibidores de Proteínas Quinasas/farmacocinética , Adolescente , Factores de Edad , Área Bajo la Curva , Superficie Corporal , Niño , Preescolar , Cálculo de Dosificación de Drogas , Interacciones Farmacológicas , Fluconazol/farmacología , Humanos , Itraconazol/farmacología , Tasa de Depuración Metabólica , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Rifampin/farmacologíaRESUMEN
Dual Bcl-2/Bcl-xL inhibitors are expected to deliver therapeutic benefit in many haematological and solid malignancies, however, their use is limited by tolerability issues. AZD4320, a potent dual Bcl-2/Bcl-xL inhibitor, has shown good efficacy however had dose limiting cardiovascular toxicity in preclinical species, coupled with challenging physicochemical properties, which prevented its clinical development. Here, we describe the design and development of AZD0466, a drug-dendrimer conjugate, where AZD4320 is chemically conjugated to a PEGylated poly-lysine dendrimer. Mathematical modelling was employed to determine the optimal release rate of the drug from the dendrimer for maximal therapeutic index in terms of preclinical anti-tumour efficacy and cardiovascular tolerability. The optimised candidate is shown to be efficacious and better tolerated in preclinical models compared with AZD4320 alone. The AZD4320-dendrimer conjugate (AZD0466) identified, through mathematical modelling, has resulted in an improved therapeutic index and thus enabled progression of this promising dual Bcl-2/Bcl-xL inhibitor into clinical development.