RESUMO
OBJECTIVE: The aetiology of OA is not fully understood although several adipokines such as leptin are known mediators of disease progression. Since leptin levels were increased in synovial fluid compared to serum in OA patients, it was suggested that joint cells themselves could produce leptin. However, exact mechanisms underlying leptin production by chondrocytes are poorly understood. Nevertheless, prednisolone, although displaying powerful anti-inflammatory properties has been recently reported to be potent stimulator of leptin and its receptor in OA synovial fibroblasts. Therefore, we investigated, in vitro, spontaneous and prednisolone-induced leptin production in OA chondrocytes, focusing on transforming growth factor-ß (TGFß) and Wnt/ß-catenin pathways. DESIGN: We used an in vitro dedifferentiation model, comparing human freshly isolated hip OA chondrocytes cultivated in monolayer during 1 day (type II, COL2A1 +; type X, COL10A1 + and type I collagen, COL1A1 -) or 14 days (COL2A1 -; COL10A1 - and COL1A1+). RESULTS: Leptin expression was not detected in day1 OA chondrocytes whereas day14 OA chondrocytes produced leptin, significantly increased with prednisolone. Activin receptor-like kinase 1 (ALK1)/ALK5 ratio was shifted during dedifferentiation, from high ALK5 and phospho (p)-Smad2 expression at day1 to high ALK1, endoglin and p-Smad1/5 expression at day14. Moreover, inactive glycogen synthase kinase 3 (GSK3) and active ß-catenin were only found in dedifferentiated OA chondrocytes. Smad1 and ß-catenin but not endoglin stable lentiviral silencing led to a significant decrease in leptin production by dedifferentiated OA chondrocytes. CONCLUSIONS: Only dedifferentiated OA chondrocytes produced leptin. Prednisolone markedly enhanced leptin production, which involved Smad1 and ß-catenin activation.
Assuntos
Condrócitos/metabolismo , Leptina/metabolismo , Osteoartrite do Quadril/metabolismo , RNA Mensageiro/metabolismo , Receptores de Activinas Tipo II/efeitos dos fármacos , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Cartilagem Articular/citologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Desdiferenciação Celular/efeitos dos fármacos , Desdiferenciação Celular/genética , Condrócitos/efeitos dos fármacos , Colágeno Tipo X/efeitos dos fármacos , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Glucocorticoides/farmacologia , Quinase 3 da Glicogênio Sintase/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Técnicas In Vitro , Linfotoxina-alfa/efeitos dos fármacos , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Masculino , Metaloproteinase 13 da Matriz/efeitos dos fármacos , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Pessoa de Meia-Idade , Osteoartrite do Quadril/genética , Prednisolona/farmacologia , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/efeitos dos fármacos , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/efeitos dos fármacos , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fatores de Transcrição SOX9/efeitos dos fármacos , Fatores de Transcrição SOX9/metabolismo , Proteína Smad1/efeitos dos fármacos , Proteína Smad1/genética , Proteína Smad1/metabolismo , Proteína Smad2/efeitos dos fármacos , Proteína Smad2/genéticaRESUMO
Angina is chest pain induced by ischemia of the heart muscle, generally due to obstruction or spasm of the coronary arteries. People that suffer from average to severe cases of angina have an increased percentage of death before the age of 55, usually around 60%. Therefore, prevention of major complications, optimizing diagnosis, prognosis and therapeutics are of primary importance. The main objective of this study was to uncover biomarkers by comparing serum protein profiles of patients suffering from stable or unstable angina and controls. We identified by non-targeted proteomic approach and confirmed by the means of independent techniques, the differential expression of several proteins indicating significantly increased vascular inflammation response, disturbance in the lipid metabolism and in atherogenic plaques stability.