Influence of Soluble Mediators and Mechanical Forces on Articular Cartilage Cells

5 Influence of Soluble Mediators and Mechanical Forces on Articular Cartilage Cells 

Vitamin D may regulate calcification of cartilage by regulating chondrocyte synthesis of proteoglycans. l,25(OH)2D3, an active metabolite of vitamin D has been shown to produce a concentration-dependent reduction in an immortalized rat chondrocyte cell line. Both vitamin D and l,25(OH)2D3 are considered secosteroids with vitamin D receptors, which includes cytosolic/nuclear proteins that bind specifically to the secosteroid as it transits the plasma membrane. 

Ascorbic acid stimulates proliferation of rabbit chondrocytes at high cell density, chick embryo and bovine articular chondrocytes, and rabbit cartilage explants. Although evidence suggests that ascorbic acid treatment does not directly stimulate transcription of ECM products, cultured chondrocytes undergo changes in gene expression characteristic of hypertrophy. 

Implicated in induction and differentiation of cartilaginous tissues during development are a number of growth factors and cytokines, including the TGF-P superfamily. Those implicated include bone morphogenetic protein subfamilies, fibroblast growth factor family, insulinlike growth factor family, 

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