Glucocorticoid hormone adversely affects the growth and regeneration of cartilage in vitro

Apical portion of condylar cartilage of neonatal mice served as an experimental model to study the in vitro effects of elevated concentration of triamcinolone, a fluorinated synthetic analogue of cortisol on cartilage cell growth and development. Triamcinolone acetonide (10(-6) M) led to a significant decrease in the proliferative rate of chondroprogenitor cells along with an inhibition of the chondrogenic differentiation pathway. By 5 days in culture, control explants exhibited a pronounced increase in size and succeeded to reconstitute their native form. In hormone-treated cultures, the explants also elongated yet the increase was due to an accelerated cellular hypertrophy rather than increase in cell number. The findings of the present study which were based upon quantitative 3H-thymidine autoradiography as well as upon determination of 3H-thymidine incorporation suggest that in vitro corticosteroid hormone depresses pre-chondroblasts proliferation along with an interference in the normal differentiative pathway of the above cells.