Regeneration of static-load-degenerated articular cartilage extracellular matrix by vitamin C supplementation.

The effect of a physiological dose of vitamin C (100 μg/ml) on goat articular cartilage chondrocytes cultured in an alginate matrix and subjected to static pressurization of 2.4 MPa was investigated. Biochemical analyses of DNA, glycosaminoglycan (GAG), collagen and protease activity were carried out in various matrix fractions, i.e. cellular matrix (CM) and further removed matrix (FRM), and in culture medium. The treatment of chondrocytes with vitamin C after static pressure increased the GAG content in both CM and FRM ( P < 0.03) as compared with control or vitamin C/ static load alone. The collagen content of chondrocytes treated with vitamin C alone and vitamin C after static load also increased significantly in FRM ( P < 0.003) as compared with control and static load alone. The specific activity of protease in CM and FRM decreased after vitamin C supplementation both with and without static pressure relative to control ( P < 0.003). Transmission electron-microscopic images showed a mixed population of spherical and elliptical chondrocytes when vitamin C was added after static load as compared with static load alone where only elliptical cells were seen. Abundant pericellular and collagen fibrils were seen in this group of chondrocytes as compared with all other groups and the control. The results thus show that, in vitro, vitamin C supplementation of chondrocytes after static loading has the potential to reduce the morphological and biochemical degeneration of chondrocytes caused by static loading, thereby improving the cellular health and functioning of articular cartilage. [ABSTRACT FROM AUTHOR]