ELASTIN EXPRESSION IS UP-REGULATED BY RETINOIC ACID BUT NOT BY RETINOL IN CHICK EMBRYONIC SKIN FIBROBLASTS

Effects of retinoid derivatives (retinol and retinoic acid) on elastin expression and cell proliferation in chick embryonic skin fibroblasts were studied. Retinoic acid inhibited cell proliferation one half of control at the concentration of 10(-5) M. Retinoic acid exhibited stim ulatory effect on eIastin synthesis with a maximum stimulation of 2.0- fold al th concentration of 10(-6) M for 24 h treatment. Elastin level detected by Western blot analysis in the pooled conditioned medium wa s compatible with the increase of elastin synthesis by retinoic acid t reatment. Comparable increase in elastin mRNA level was observed by re tinoic acid treatment. Retinol showed no significant effects on either cell proliferation or elastin expression. The results indicate that r etinoic acid was potentially active and retinol was inactive for modul ation of cell proliferation and elastin expression. (C) 1997 Elsevier Science Ireland Ltd.