The effect of certain anti-inflammatory steroids on collagen synthesis in vitro

Abstract

The effect of some anti-inflammatory steroids (prednisolone, and different derivatives of hydrocortisone, dexamethasone and betamethasone) on the synthesis and extra- and intracellular distribution of collagen was studied using chick embryo tendon cells. The concentrations of steroids varied between 1 × 10 −3 M and 1 × 10 −7 M. All steroids having an effect decreased the synthesis of collagen and the amount of labeled collagen decreased more in the medium than in the cells. Great variations in the inhibitory activity between different derivatives of steroids were noticed. Hydrocortisone was as inhibitory as hydrocortisone butyrate but both decreased collagen synthesis more than succinate or phosphate derivatives of hydrocortisone. Betamethasone-17-valerate was the most potent inhibitor among the steroids tested, whereas its alcohol and phosphate forms were ineffective. Dexamethasone and its phosphate derivative did not affect collagen synthesis in this system. The inhibitory potency of prednisolone on collagen synthesis was about the same as that of hydrocortisone. No steroid caused an accumulation of labeled collagen into cells and the decrease in the amount of collagen followed the decrease in total amount of labeled proteins. The results suggest that the inhibition of collagen synthesis by anti-inflammatory steroids is a consequence of a general inhibition of protein synthesis.