Nanotechnology and DNA Repair

Wed, 09/09/2015 - 12:34

DNA repair enzymes

UV-B rays (290-320 nm) damage skin DNA through the formation of cyclobutane pyrimidine dimers (CPDs). If left unrepaired, CDPs are mutagenic and contribute to photocarcinogenesis through suppression of the skin’s immune system. CPDs are the principal cause of melanomas. Sunscreens prevent this by protecting the skin from UV-B rays, either reflecting these rays or transforming them into heat. Topical application of the enzyme photolyase, for instance, recognizes and binds to CPDs, reverting them to normal form after exposure to photoreactivating light (300-500nm). The addition of photolyase to sunscreens has proven to contribute both to the prevention of DNA damage and its repair. Photolyase in products for skincare is generally prepared from Anacystis nidulans and listed in labels as plankton extract, some examples include PRIORI MD’s Clinical Recovery Serum, and Ocean Rescue Marine Contour Cream.

Nanomaterials as carriers

Nanotechnology, the science of manipulating matter at a miniscule level, has numerous applications. In the case of skincare products, nanomaterials act as drug carriers and are able to pass the almost impermeable skin barrier. A current trend in cosmetics production is incorporating clinically proven ingredients into cosmetics through the use of nanomaterials. This trend is meant to fill the gap between beauty products that cleanse and moisturize and therapeutic cosmetics with demonstrated efficacy. Many major cosmetic brands are incorporating nanotechnology to their products, such as L’Oreal’s RevitaLift Double Lifting, and Lancome’s Rénergie Microlift. Sunscreens are the most common cosmetic products using nanomaterials, with titanium dioxide and zinc dioxide compounds in doses of 20nm to provide broad protection against ultraviolet light. The nanocarriers currently used for skin care include liposomes, fullerenes, and solid lipid nanoparticles. Liposomes, concentric mono or bilayered vesicles generally composed of phospholipids, are believed to be able to fuse with cell membranes to release content inside the cell. These are the most studied and the used carriers in cosmetics. Nevertheless, studies on their ability to permeate the skin are inconsistent. Fullerenes – carbon spheres of approximately 1nm in diameter – can encapsulate medications within their spherical structure but are mostly used to capture free radicals. Finally, solid lipid nanoparticles are oily droplets of lipids used to protect encapsulated ingredients from degradation and deliver cosmetic agents over a long time. These particles are able to improve penetration into the strateum corneum and can enhance the UV protection effect of sunscreen.