Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Med Chem ; 65(2): 1567-1584, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34931844

RESUMEN

The serine/threonine kinase SGK1 is an activator of the ß-catenin pathway and a powerful stimulator of cartilage degradation that is found to be upregulated under genomic control in diseased osteoarthritic cartilage. Today, no oral disease-modifying treatments are available and chronic treatment in this indication sets high requirements for the drug selectivity, pharmacokinetic, and safety profile. We describe the identification of a highly selective druglike 1H-pyrazolo[3,4-d]pyrimidine SGK1 inhibitor 17a that matches both safety and pharmacokinetic requirements for oral dosing. Rational compound design was facilitated by a novel hSGK1 co-crystal structure, and multiple ligand-based computer models were applied to guide the chemical optimization of the compound ADMET and selectivity profiles. Compounds were selected for subchronic proof of mechanism studies in the mouse femoral head cartilage explant model, and compound 17a emerged as a druglike SGK1 inhibitor, with a highly optimized profile suitable for oral dosing as a novel, potentially disease-modifying agent for osteoarthritis.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Modelos Animales de Enfermedad , Proteínas Inmediatas-Precoces/antagonistas & inhibidores , Microsomas Hepáticos/efectos de los fármacos , Osteoartritis/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Pirimidinas/química , Animales , Artritis Experimental/enzimología , Artritis Experimental/patología , Ligandos , Masculino , Ratones , Ratones Endogámicos C57BL , Osteoartritis/enzimología , Osteoartritis/patología , Inhibidores de Proteínas Quinasas/química , Ratas , Ratas Sprague-Dawley
2.
ACS Med Chem Lett ; 6(1): 73-8, 2015 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-25589934

RESUMEN

From a virtual screening starting point, inhibitors of the serum and glucocorticoid regulated kinase 1 were developed through a combination of classical medicinal chemistry and library approaches. This resulted in highly active small molecules with nanomolar activity and a good overall in vitro and ADME profile. Furthermore, the compounds exhibited unusually high kinase and off-target selectivity due to their rigid structure.

3.
Bioconjug Chem ; 26(3): 383-8, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25629889

RESUMEN

Targeted drug-delivery methods are crucial for effective treatment of degenerative joint diseases such as osteoarthritis (OA). Toward this goal, we developed a small multivalent structure as a model drug for the attenuation of cartilage degradation. The DOTAM (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid amide)-based model structure is equipped with the cathepsin D protease inhibitor pepstatin A, a fluorophore, and peptide moieties targeting collagen II. In vivo injection of these soluble probes into the knee joints of mice resulted in 7-day-long local retention, while the drug carrier equipped with a scrambled peptide sequence was washed away within 6-8 h. The model drug conjugate successfully reduced the cathepsin D protease activity as measured by release of GAG peptide. Therefore, these conjugates represent a promising first drug conjugate for the targeted treatment of degenerative joint diseases.


Asunto(s)
Acetamidas/administración & dosificación , Cartílago/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Compuestos Heterocíclicos con 1 Anillo/administración & dosificación , Osteoartritis/tratamiento farmacológico , Acetamidas/metabolismo , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Artritis Experimental/patología , Cartílago/metabolismo , Cartílago/patología , Portadores de Fármacos/metabolismo , Compuestos Heterocíclicos con 1 Anillo/metabolismo , Ratones , Osteoartritis/metabolismo , Osteoartritis/patología , Porcinos
4.
Chem Sci ; 6(11): 6256-6261, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30090244

RESUMEN

Osteoarthritis (OA) is one of the most common diseases in the aging population. While disease progress in humans is monitored indirectly by X-ray or MRI, small animal OA lesions detection always requires surgical intervention and histology. Here we introduce bimodal MR/NIR probes based on cartilage-targeting 1,4,7,10-tetraazacyclododecane 1,4,7,10-tetraacetic acid amide (DOTAM) that are directly administered to the joint cavity. We demonstrate applications in healthy and diseased rat joints by MRI in vivo. The same joints are inspected post-mortem by fluorescence microscopy, showing not only the precise location of the reagents but also revealing details such as focal cartilage damage and chondrophyte or osteophyte formation. This allows for determining the distinct pathological state of the disease and the regeneration capability of the animal model and will help to correctly assess the effect of potential disease modifying OA drugs (DMOADs) in the future.

5.
J Chem Inf Model ; 54(3): 987-91, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24528206

RESUMEN

We present the discovery of low molecular weight inhibitors of human immunodeficiency virus 1 (HIV-1) protease subtype B that were identified by structure-based virtual screening as ligands of an allosteric surface cavity. For pocket identification and prioritization, we performed a molecular dynamics simulation and observed several flexible, partially transient surface cavities. For one of these presumable ligand-binding pockets that are located in the so-called "hinge region" of the identical protease chains, we computed a receptor-derived pharmacophore model, with which we retrieved fragment-like inhibitors from a screening compound pool. The most potent hit inhibited protease activity in vitro in a noncompetitive mode of action. Although attempts failed to crystallize this ligand bound to the enzyme, the study provides proof-of-concept for identifying innovative tool compounds for chemical biology by addressing flexible protein models with receptor pocket-derived pharmacophore screening.


Asunto(s)
Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/farmacología , Proteasa del VIH/metabolismo , VIH-1/enzimología , Regulación Alostérica/efectos de los fármacos , Sitios de Unión , Diseño de Fármacos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Proteasa del VIH/química , Humanos , Ligandos , Simulación de Dinámica Molecular , Relación Estructura-Actividad
6.
Arthritis Rheum ; 54(11): 3533-44, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17075858

RESUMEN

OBJECTIVE: Despite many research efforts in recent decades, the major pathogenetic mechanisms of osteoarthritis (OA), including gene alterations occurring during OA cartilage degeneration, are poorly understood, and there is no disease-modifying treatment approach. The present study was therefore initiated in order to identify differentially expressed disease-related genes and potential therapeutic targets. METHODS: This investigation consisted of a large gene expression profiling study performed based on 78 normal and disease samples, using a custom-made complementary DNA array covering >4,000 genes. RESULTS: Many differentially expressed genes were identified, including the expected up-regulation of anabolic and catabolic matrix genes. In particular, the down-regulation of important oxidative defense genes, i.e., the genes for superoxide dismutases 2 and 3 and glutathione peroxidase 3, was prominent. This indicates that continuous oxidative stress to the cells and the matrix is one major underlying pathogenetic mechanism in OA. Also, genes that are involved in the phenotypic stability of cells, a feature that is greatly reduced in OA cartilage, appeared to be suppressed. CONCLUSION: Our findings provide a reference data set on gene alterations in OA cartilage and, importantly, indicate major mechanisms underlying central cell biologic alterations that occur during the OA disease process. These results identify molecular targets that can be further investigated in the search for therapeutic interventions.


Asunto(s)
Cartílago/patología , Perfilación de la Expresión Génica/métodos , Osteoartritis de la Rodilla/genética , Osteoartritis de la Rodilla/patología , Anciano , Anciano de 80 o más Años , Diferenciación Celular , Condrocitos/metabolismo , Condrocitos/patología , Análisis por Conglomerados , Dermatoglifia del ADN , Metabolismo Energético/genética , Perfilación de la Expresión Génica/normas , Marcadores Genéticos , Predisposición Genética a la Enfermedad/epidemiología , Humanos , Incidencia , Persona de Mediana Edad , Osteoartritis de la Rodilla/epidemiología , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
7.
Front Biosci ; 10: 2027-35, 2005 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15970475

RESUMEN

Cultures of primary chondrocytes as in vitro model systems for studying the cellular behavior of chondrocytes are notoriously difficult to cultivate and propagate. One way to circumvent these problems appears to be the use of immortalized/immortal chondrocytic cell lines. In the present study, we were interested whether the chondrosarcoma derived HCS-2/8 cells are suitable for studying major cellular reaction pattern in response to key anabolic (BMP-7) and catabolic (IL-1beta) factors. Therefore, we used cDNA array and real-time PCR technology in order to evaluate gene expression triggered by stimulation with IL-1beta (0,1-100 ng/ml) and BMP-7 in confluent monolayer cultures. HCS-2/8 cells hardly responded to IL-1beta, but showed good responsiveness to BMP-7. We found 12 genes up- and 17 significantly down-regulated by BMP-7 (out of 340 investigated genes). Besides the expected activation of anabolic genes chondrocytic cells after BMP-stimulation try to neutralize activation of the BMP-signalling cascade by expressing intra- and extracellular BMP-antagonists. Chondrosarcoma derived cell lines are a potential substitute for primary articular chondrocytes promising consistent expression of a differentiated chondrocyte phenotype with sufficient proliferative capacity. However, as shown by this study one needs to carefully select the cell line depending on the effects which one intends to study. In this respect, HCS-2/8 cells are a validated tool for studying BMP-effects on chondrocytes, but not e.g. effects of interleukin-1.


Asunto(s)
Proteínas Morfogenéticas Óseas/farmacología , Condrosarcoma/patología , Expresión Génica/efectos de los fármacos , Interleucina-1/farmacología , Factor de Crecimiento Transformador beta/farmacología , Proteína Morfogenética Ósea 7 , Perfilación de la Expresión Génica , Humanos , Células Tumorales Cultivadas
8.
Arthritis Res Ther ; 7(2): R274-84, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15743474

RESUMEN

Osteoarthritis is the most common degenerative disorder of the modern world. However, many basic cellular features and molecular processes of the disease are poorly understood. In the present study we used oligonucleotide-based microarray analysis of genes of known or assumed relevance to the cellular phenotype to screen for relevant differences in gene expression between normal and osteoarthritic chondrocytes. Custom made oligonucleotide DNA arrays were used to screen for differentially expressed genes in normal (n = 9) and osteoarthritic (n = 10) cartilage samples. Real-time polymerase chain reaction (PCR) with gene-specific primers was used for quantification. Primary human adult articular chondrocytes and chondrosarcoma cell line HCS-2/8 were used to study changes in gene expression levels after stimulation with interleukin-1beta and bone morphogenetic protein, as well as the dependence on cell differentiation. In situ hybridization with a gene-specific probe was applied to detect mRNA expression levels in fetal growth plate cartilage. Overall, more than 200 significantly regulated genes were detected between normal and osteoarthritic cartilage (P < 0.01). One of the significantly repressed genes, Tob1, encodes a protein belonging to a family involved in silencing cells in terms of proliferation and functional activity. The repression of Tob1 was confirmed by quantitative PCR and correlated to markers of chondrocyte activity and proliferation in vivo. Tob1 expression was also detected at a decreased level in isolated chondrocytes and in the chondrosarcoma cell line HCS-2/8. Again, in these cells it was negatively correlated with proliferative activity and positively with cellular differentiation. Altogether, the downregulation of the expression of Tob1 in osteoarthritic chondrocytes might be an important aspect of the cellular processes taking place during osteoarthritic cartilage degeneration. Activation, the reinitiation of proliferative activity and the loss of a stable phenotype are three major changes in osteoarthritic chondrocytes that are highly significantly correlated with the repression of Tob1 expression.


Asunto(s)
Cartílago Articular/metabolismo , Perfilación de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/fisiología , Osteoartritis/metabolismo , Proteínas Supresoras de Tumor/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Proteína Morfogenética Ósea 7 , Proteínas Morfogenéticas Óseas/farmacología , Diferenciación Celular , División Celular , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/metabolismo , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrosarcoma/patología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hibridación in Situ , Interleucina-1/farmacología , Péptidos y Proteínas de Señalización Intracelular/genética , Antígeno Ki-67/análisis , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoartritis/genética , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta/farmacología , Proteínas Supresoras de Tumor/biosíntesis , Proteínas Supresoras de Tumor/genética
9.
Methods Mol Med ; 100: 109-28, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15280592

RESUMEN

The regulation of chondrocytes in osteoarthritic cartilage and the expression of specific gene products by these cells during early-onset and late-stage osteoarthritis are not well characterized. With the introduction of cDNA array technology, the measurement of thousands of different genes in one small tissue sample can be carried out. Interpretation of gene expression analyses in articular cartilage is aided by the fact that this tissue contains only one cell type in both normal and diseased conditions. However, care has to be taken not to over- and misinterpret results, and some major challenges must be overcome in order to utilize the potential of this technology properly in the field of osteoarthritis.


Asunto(s)
Cartílago/metabolismo , Condrocitos/metabolismo , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Osteoartritis/genética , Cartílago/química , Condrocitos/química , Humanos , Osteoartritis/metabolismo , ARN/aislamiento & purificación
10.
J Biol Chem ; 278(15): 12854-63, 2003 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-12562769

RESUMEN

The importance of a functional Krebs cycle for energy generation in the procyclic stage of Trypanosoma brucei was investigated under physiological conditions during logarithmic phase growth of a pleomorphic parasite strain. Wild type procyclic cells and mutants with targeted deletion of the gene coding for aconitase were derived by synchronous in vitro differentiation from wild type and mutant (Delta aco::NEO/Delta aco::HYG) bloodstream stage parasites, respectively, where aconitase is not expressed and is dispensable. No differences in intracellular levels of glycolytic and Krebs cycle intermediates were found in procyclic wild type and mutant cells, except for citrate that accumulated up to 90-fold in the mutants, confirming the absence of aconitase activity. Surprisingly, deletion of aconitase did not change differentiation nor the growth rate or the intracellular ATP/ADP ratio in those cells. Metabolic studies using radioactively labeled substrates and NMR analysis demonstrated that glucose and proline were not degraded via the Krebs cycle to CO(2). Instead, glucose was degraded to acetate, succinate, and alanine, whereas proline was degraded to succinate. Importantly, there was absolutely no difference in the metabolic products released by wild type and aconitase knockout parasites, and both were for survival strictly dependent on respiration via the mitochondrial electron transport chain. Hence, although the Krebs cycle enzymes are present, procyclic T. brucei do not use Krebs cycle activity for energy generation, but the mitochondrial respiratory chain is essential for survival and growth. We therefore propose a revised model of the energy metabolism of procyclic T. brucei.


Asunto(s)
Aconitato Hidratasa/metabolismo , Metabolismo Energético/fisiología , Trypanosoma brucei brucei/fisiología , Aconitato Hidratasa/deficiencia , Aconitato Hidratasa/genética , Animales , Ciclo del Ácido Cítrico , Eliminación de Gen , Glucosa/metabolismo , Glutamato Deshidrogenasa/deficiencia , Glutamato Deshidrogenasa/genética , Glutamato Deshidrogenasa/metabolismo , Isocitrato Deshidrogenasa/deficiencia , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Complejo Cetoglutarato Deshidrogenasa/deficiencia , Complejo Cetoglutarato Deshidrogenasa/genética , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Espectroscopía de Resonancia Magnética , Cianuro de Potasio/farmacología , Transfección , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/crecimiento & desarrollo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...