Dexamethasone reduces ATDC5 chondrocyte cell viability by inducing autophagy.

Prolonged use of glucocorticoids (GCs) for the treatment of chronic inflammatory and autoimmune diseases commonly exerts various side-effects, including impairment of skeletal development. However, the effect of GCs on chondrocytes, which play a key role in skeletal development, has been rarely reported. In the present study, autophagy was induced in the ATDC5 chondrocyte cell line following treatment with dexamethasone (Dex) at doses of 1­100 µM, and that this effect can be inhibited by RU486, a GC antagonist. Autophagy induced by the highest Dex dose (100 µM) was associated with a reduction in ATDC5 cell viability. We conclude that high doses of GC can reduce ATDC5 chondrocyte cell viability by inducing autophagy.