Extracellular Matrix and Skin Diseases

Abstract

Recent advances in extracellular matrix research concerning skin diseases were reviewed. Several different forms of amino terminal splicings of type VI collagen were identified ; these might contribute to binding with decorin or biglycan. Type XVI collagen is synthesized by nonadherent and proliferative fibroblasts. This collagen is expressed in dermal dendrocytes and might contribute to their anchorage in the papillary dermis. Dermatopontin, which is a low molecular weight component abundant in dermis, interacts with decorin and TGF-β1, and modulates the action of TGF-β1. The null mouse for this molecule showed dermal thinning and increased elasticity. Only a little is known about the molecular defect of congenital cutis laxa, but elastin gene mutations have been reported in patients with autosomal dominant cutis laxa. The gene targeted mouse for fibulin 5 has recently been reported ; it mimics human cutis laxa with vascular and pulmonary involvement. Myofibroblasts play important roles in fibrosing diseases such as hypertrophic scar, keloid, and interstitial reaction against epithelial tumors. Transforming growth factor beta1 is one of most potent inducers of myofibroblasts from fibroblasts, and the expression of EDA, a splicing form of fibronectin, leads this phenotypic change. Antifibrotic therapy that involves blocking connective tissue growth factor or regulating other transcription factors, e. g. Sp1 or hcKrox, is expected in the future.