Collagen And Elastic Tissue In Aging Skin

Background: Laxity and wrinkle are the evident characters of aging skin. As the main component of the derm, elastics and collagens had some changes in the aging skin.Objective: To observe the alteration of elastics and collagens in the aging skin.Methods: Study 80 skin biopsies of health volunteers from sun-exposed areas of the face, with or without wrinkles(orbit, forehead or cheek), and non-sun-exposed areas(abdomen or hip). We use different histological techniques involving Haematoxylin-eosin staining, Weigert staining, Immunohistochemistry and Picric acid-Sirius red staining which observed by polarization microscopy combined with image analysis. Results: 1. Collagen IV has similar content among various skin areas and among various ages. 2. Type I collagen fibers, which showed red or yellow intense birefringence, were decreased under sun-exposed, especially wrinkling-incident area in comparison with non-sun-exposed skin . And their also decreased companying with ageing in the same area. 3. Not only the elastics tissue statistically significantly increased in sun-exposed area but also the elastic property had been destroyed. On the contrary, the elastics in non-sun-exposed skin, had decreased and ruptured. 4. At the bottom of the wrinkle, besides collagen IV was interrupted and collagen decreased, the elastotic tissue accumulated under the epidermis which caused the winkles into being.