Fibroblast changes in cutaneous ageing.

With ageing there are progressive modifications in the connective tissue of the dermis. In ten young subjects the collagenous bundles are thick and the fibroblasts are active cells in close contact with collagen fascicles. In ten elderly subjects collagen fibres are fragmented and the fibroblasts are quiescent, without any contact with collagen. In ageing the most important lesion is the destruction of the relationship between fibroblasts and interstitial matrix. A role for fibronectin in this adhesion is suggested: in old subjects the papillary network of fibronectin is poorly developed. Furthermore, in the fibroblast we can see architectural changes in the cytoskeleton; this modification breaks up the cytoskeleton - plasma membrane - fibronectin unit and explains the secretory and metabolic changes observed in ageing, the dysfunction of the cell-interstitial matrix unit, and also the structural changes.