Glycosaminoglycans in granulation tissue and hypertrophic scars

The glycosaminoglycans of granulation tissue from regenerating tissue of severely burned patients was investigated and compared with those of (1) hypertrophic scars and keloids, (2) mature scars and (3) normal skin. Results clearly show that granulation tissues have high levels of chondroitin-4-sulphate relative to the other glycosaminoglycans as compared to low levels in mature scar and normal skin. The chondroitin-4-sulphate levels of children's granulation tissue was significantly higher than the levels from hypertrophic scars of children, however the chondroitin-4-sulphate levels of adults' granulation tissue was not significantly different from those of hypertrophic scars. The dermatan sulphate levels of granulation tissue are significantly lower than the dermatan sulphate levels of hypertrophic scars, mature scars or normal skin. This suggests that chondroitin-4-sulphate is related to proliferation of collagen in granulation tissue, and that as the collagen matures and the normal scar forms, chondroitin-4-sulphate levels decrease and dermatan sulphate increases. When the hypertrophic scar develops, the high chondroitin-4-sulphate levels remain high, dermatan sulphate increases, but does not reach the levels of those in the mature scar. Neither hypertrophic scar nor mature scar have levels of hyaluronic acid as high as normal skin. However, our data suggest that adult granulation tissue may have relatively high hyaluronic acid levels. It is suggested that the different distribution of glycosaminoglycans in granulation tissue influences the size and shape of collagen filaments and may also influence the rate of synthesis of collagen.