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Improving 2D and 3D Skin In Vitro Models Using Macromolecular Crowding
Published on: August 22, 2016
From skin microrelief to wrinkles. An area ripe for investigation
Gérald E Piérard1, Isabelle Uhoda, Claudine Piérard-Franchimont
1Department of Dermatopathology, University Hospital of Liège, Belgium. Gerald.Pierard@ulg.ac.be
Abstract:
Skin microrelief alters progressively with age. Wrinkles do not result from these changes but are superimposed upon them. Wrinkles result from structural changes in the epidermis, dermis and hypodermis. Four types of wrinkles can be recognized. Type 1 wrinkles are atrophic. Type 2 wrinkles are elastotic. Type 3 wrinkles are expressional. Type 4 wrinkles are gravitational. Each type of wrinkle is characterized by distinct microanatomical changes and each type of wrinkle develops in specific skin regions. Each is likely to respond differently to treatment. Skin microrelief and skin folds can be identified on histological examination. By contrast, only minimal dermal changes are found beneath permanent or reducible wrinkles compared with immediately adjacent skin. A series of objective and non-invasive methods is available to quantify the severity of wrinkling.
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