Downregulation of decorin expression in dermal fibroblasts by interleukin-4.
Decorin, a chondroitin/dermatan sulphate proteoglycan, plays an important role in the assembly of extracellular matrix components. In this study, we investigated the influence of interleukin-4 (IL-4) on the expression of decorin and sulphated glycosamino-glycans (GAGs) in cultures of human skin fibroblasts. IL-4 inhibited the expression of decorin mRNA and its core protein synthesis. IL-4 stimulated dermatan sulphate but decreased chondroitin sulphate synthesis without altering the total amount of sulphated GAGs. IL-4 had no effect on the initiation activity of the dermatan sulphate and chondroitin sulphate chains, as evaluated by the effect of exogenous beta-xyloside that acts as an artificial chain initiator for dermatan sulphate and chondroitin sulphate biosynthesis. Type I collagen mRNA levels and protein synthesis were increased by this IL-4. Therefore, the effects of IL-4 on decorin and GAGs as well as type I collagen may have important implications for wound healing and for the treatment of several fibrosing diseases.
Kuroda
K
K
Department of Dermatology, School of Medicine, Chiba University, Japan.
Shinkai
H
H
D000328:Adult; D002478:Cells, Cultured; D003094:Collagen / Q000235:genetics; D058575:Decorin; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology*; D011509:Proteoglycans / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D012867:Skin / Q000166:cytology / Q000378:metabolism; D014945:Wound Healing
C546878:DCN protein, human; D058575:Decorin; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D011509:Proteoglycans; D012333:RNA, Messenger; D015847:Interleukin-4; D003094:Collagen