Mesenchymal stem cells (MSCs) are widely used in cartilage tissue engineering to repair articular cartilage defects. However, hypertrophy of chondrocytes derived from MSCs might hinder the stabilization of hyaline cartilage. Thus, it is very important to find a suitable way to maintain the chondrogenic phenotype of chondrocytes. It has been reported that cordycepin has anti-inflammatory and ant...

Background: Integrin-associated protein (IAP) /CD47, a member of immunoglobulin super family (IgSF), is expressed in a variety of cell types. In the present work, the expression pattern of IAP/ CD47 in normal and osteoarthritis (OA) human articular cartilage and its role in mechanotransduction pathway following mechanical stimulation have been studied. Methods: Using immunohistochemistry and st...

BACKGROUND Lubricin, a mucinous glycoprotein secreted by synoviocytes and chondrocytes plays an important role in reducing the coefficient of friction in mammalian joints. Elevated cartilage surface friction is thought to cause chondrocyte loss; however, its quantification and methodological approaches have not been reported. We adapted a stereological method and incorporated vital cell stainin...

The possibility that growth hormone (GH) has effects on long bone growth independent of insulin-like growth factor-I (IGF-I) has long been debated. If this is true, then long bone growth should be more profoundly affected by the absence of GH (since both GH and GH-stimulated IGF-I effects are absent) than by the absence of IGF-I alone (since GH is still present and actually elevated). To test t...

Hypophosphatasia is a rare heritable disorder caused by inactivating mutations in the gene (Alpl) that encodes tissue nonspecific alkaline phosphatase (TNAP). Hypophosphatasia with onset in infants and children can manifest as rickets. How TNAP deficiency leads to bone hypomineralization is well explained by TNAP's primary function of pyrophosphate hydrolysis when expressed in differentiated bo...

OBJECTIVE Disturbed anabolic signalling might contribute to the decreased chondrocyte proteoglycan (PG) synthesis during joint inflammation. Articular cartilage obtained from mouse knee joints with experimentally-induced arthritis exhibits a state of nonresponsiveness towards stimulation of chondrocyte PG synthesis by insulin-like growth factor-1 (IGF-1). Investigations were carried out on the ...

During ex vivo growth as monolayer cultures, chondrocytes proliferate and undergo a process of de-differentiation. This process involves a change in morphology and a change from expression of chondrocyte-specific genes to that of genes that are normally expressed in fibroblasts. Transfer of the monolayer chondrocyte culture to three-dimensional culture systems induces the cells to re-acquire a ...

when grown in monolayer culture at low density and with the addition of serum, cartilage cells dedifferentiate or are overgrown by fibroblast-like cells. the aim of this study was to optimize the cultivation of chondrocytes in monolayer culture and to slow down their transformation or their overgrowth by fibroblast-like cells. the interaction between chondrocytes and cartilage-specifc matrix is...

objective(s) articular cartilage tissue defects cannot be repaired by the proliferation of resident chondrocytes. autologous chondrocyte transplantation (act) is a relatively new therapeutic approach to cover full thickness articular cartilage defects by in vitro grown chondrocytes from the joint of a patient. therefore, we investigated the redifferentiation capability of human chondrocytes mai...

Exact coordination of growth plate chondrocyte proliferation is necessary for normal endochondral bone development and growth. Here we show that PTHrP and TGF control chondrocyte cell cycle progression and proliferation by stimulating signaling pathways that activate transcription from the cyclin D1 promoter. The TGF pathway activates the transcription factor ATF-2, whereas PTHrP uses the relat...