RESUMO
Oncostatin M (OSM), one of the IL-6 family cytokines, inhibits adipogenic differentiation and stimulates osteoblastogenic differentiation from human bone marrow mesenchymal stem cells (hBMSCs). This functional study of OSM enabled us to develop a two-dimensional small-molecule screen that shifts hBMSC differentiation from adipocyte to osteoblast. Several structurally related compounds (isoxazoles) inhibited the accumulation of intracellular lipid droplets, whereas they promoted alkaline phosphatase activity and extracellular matrix calcification. Isoxazoles also reduced the expression of adipogenic transcription factor PPARγ and increased the levels of osteogenic transcription factors Runx2 and Osterix. They also induced the expression of the Wnt/ß-catenin downstream gene and TOPflash reporter; however, the dephosphorylated ß-catenin-active form was not significantly increased. Interestingly, the slight modification of the active compound led to a complete reversion of the dual differentiation activities. In summary, we have identified isoxazoles with anti-adipogenic and pro-osteogenic activities that provide a potential new tool for exploring the lineage commitment of mesenchymal stem cells and a possible lead for therapeutic intervention in osteopenia and osteoporosis.
Assuntos
Adipogenia/efeitos dos fármacos , Isoxazóis/farmacologia , Osteogênese/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Fosfatase Alcalina/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Isoxazóis/isolamento & purificação , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Oncostatina M/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Fator de Transcrição Sp7 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , beta Catenina/genética , beta Catenina/metabolismoRESUMO
A novel series of benzoic acid derivatives as VLA-4 antagonists were synthesized. Optimization, focusing on activity and lipophilicity needed for cell permeability, resulted in the identification of 15b and 15e with good activity (IC50 = 1.6 nM each) and moderate lipophilicity (Log D = 2.0, 1.8). Furthermore, 15e demonstrated efficacy in murine asthma model by an oral dose of 30 mg/kg.
