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| What causes wrinkles? |
| Ageing of the skin can be thought of as two simultaneous processes: Intrinsic (inside an organism or cell) and extrinsic (depending on relation with external factors) ageing. Instrinsic changes occur as a result of passage of time and produce characteristic fine wrinkles. It is also called chronological ageing. Superimposed upon these are changes resulting from exposure to extrinsic or environmental factors. One such factor is chronic sun exposure, resulting in photoageing, which by comparison with intrinsic ageing produces coarse, roughened and deeply wrinkled skin. Historically, skin that is intrinsically aged has atrophied extracellular matrix (ECM) and contains reduced levels of collagen and elastin. By comparison, photoaged skin exhibits other, numerous, alternations to the dermal ECM. These include deposition of dystrophic elastic fibers in the dermis, decreased levels of fibriallar collagens type 1 and 111, reduced number of anchoring fibril (collagen V11) and loss of the fibrillin-rich microfibrils in the papillary dermis. Levels of matrix metalloproteinases (MMP’s) are increased in both intrinsically and extrinsically aged skin and are major contributors to the remodelling of the dermal EMC in both conditions. |
| What can be done? |
| Currently, the medical treatment of choice for photoaged skin is topical application of retinoids. Previous studies have shown that application of topical all-trans retinoic acid (RA) to photoaged skin partially restores levels of collagen 1 and V11 (anchoring fibrils), reduces MMP-1 expression and ameliorates some of the clinical features such as wrinkles.del 90 In addition, treatment with RA partially restores the fibrillin-rich microfibriallar network of papillary dermis. It is common for cosmetic products to contain a number of complementary ingredients which purport to address photoaging. It has been shown that a combination of cosmetic ingredients in marketed products can include changes in dermal ECM similar to those brought about clinically by RA. Retinyl esters, such as retinyl palmitate and retinyl |
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