INHIBITION OF COLLAGEN EXPRESSION BY AZELASTINE HYDROCHLORIDE IN CULTURED SKIN FIBROBLASTS FROM NORMAL INDIVIDUALS AND SCLERODERMA PATIENTS

The effects of azelastine hydrochloride on cell proliferation and coll agen synthesis in cultured human skin fibroblasts were studied. Azelas tine inhibited cell proliferation during proliferating cell phases. Az elastine was found to inhibit collagen synthesis without altering cell proliferation during quiescent phases. It did not alter the ratio of type I to III collagen synthesis. Northern blot analysis of collagen c hain mRNAs revealed that the levels of alpha(1) (I), alpha(1) (III) an d alpha(1) (VI) mRNAs were reduced by azelastine treatment, whereas th e level of alpha(2) (VI), alpha(3) (VI) mRNAs were not significantly c hanged, These results suggest that azelastine modulates collagen synth esis at a pretranslational level, Azelastine inhibited collagen synthe sis in fibroblasts from scleroderma patients to the same extent as in normal skin fibroblasts. This drug may be useful in the treatment of f ibrotic diseases.