Dermatan sulfates of normal and scarred fascia

FGF-10 and specific structural elements of dermatan sulfate size and sulfation promote maximal keratinocyte migration and cellular proliferation

Fibroblast growth factor-10 (FGF-10) is essential for epithelial development, while other members of this family, such as FGF-7, are not. FGF-10 is abundantly released into wounds following injury, and likely an essential growth factor required for this process. To evaluate how activation of this growth factor is controlled, multiple glycosaminoglycans were combined with FGF-10 assayed by measurement of the proliferation of cell lines expressing FGF receptor-2-IIIb, or keratinocyte migration in an in vitro wound repair assay. Dermatan sulfate (DS) exhibited greater potency than heparan sulfate or other chondroitin sulfates found in wounds. Structural variants of DS between 10 and 20 disaccharides containing iduronic acid showed maximal capacity to enable FGF-10 receptor stimulation. Furthermore, FGF-10 and DS markedly enhanced migration of keratinocytes in an in vitro wound scratch assay, while FGF-7 or other glycosaminoglycans did not. These data strongly suggest that FGF-10 activity is uniquely important in wound repair and that specific DS structural properties are necessary to promote FGF-10 function. These observations identify a novel interplay between DS and FGF-10 in mediating wound repair.

Size control of decorin dermatan sulfate during remodeling of collagen fibrils in healing skin

Recently it has been reported that the molecular size of decorin dermatan sulfate (DS) was increased in healing skin after hapten application and that the elongated DS was distributed in enlarged interfibrillar space among thin collagen fibrils in situ. Here we show that such modulation of the length of decorin DS is temporary. Although the size of decorin DS was evidently increased on day 15, it decreased to almost normal size on day 35 when the altered disaccharide composition of DS was also recovered. Electron microscopic observation revealed that elongated decorin DS was localized among thin collagen fibrils packed loosely in hapten-treated skin on day 15. In contrast, decorin DS of normal size was distributed among thick collagen fibrils packed tightly on day 35. These results suggest that size control of decorin DS plays important roles in organization of collagen fibrils into bundles by regulating interfibrillar space in healing skin, particularly in maturation of collagen fibrils through shortening of decorin DS in later stages of healing.