Decreased biosynthesis of glycosaminoglycans in the skin of rats with chronic diabetes mellitus.

The skin of rats with experimental (streptozotocin-induced) chronic diabetes mellitus exhibits significant decrease in glycosaminoglycans (GAGs) content. In the present study we asked the question whether the decrease in GAGs content is a result of decline in GAG biosynthesis or an increase in their degradation. We demonstrated by a pulse-labeling experiments that diabetes results in a decrease of [14C]-glucosamine incorporation into both hyaluronic acid and sulphated GAGs. During the chase period, there was no significant degradation of the pulse-labeled GAGs, suggesting that the reduction of GAGs content in the skin of diabetic rats is a result of decrease in GAG biosynthesis. Especially the biosynthesis of sulphated GAGs is deeply reduced. This phenomenon may be one of the factors which impairs the wound healing in diabetic subjects.