Squalene and Glutathione as Naturally Synthesized Antioxidants Protecting Human Skin
Sqalene content in human skin reaches 12-18%, but in gorilla skin only 0.1%. Evolutionarily we suggested (Zobel et al., 2004) that humans could have become naked because of protection against UV performed by squalene, which is an anti-oxidant and scavenger of free radicals, and absorbs UV.
Squalene and Glutathione as Naturally Synthesized Antioxidants
Protecting Human Skin, and Their Action in Coexistence
With Plant Antioxidants in Our Diet
Sqalene content in human skin reaches 12-18%, but in gorilla skin only 0.1%. Evolutionarily we suggested (Zobel et al., 2004) that humans could have become naked because of protection against UV performed by squalene, which is an anti-oxidant and scavenger of free radicals, and absorbs UV. Every cell synthesizes squalene from acetyl-coenzyme A obtained mainly from sugars and amino acids, by the mevalonate pathway, when isoprenoids are formed, followed by steroids. Around 1950 lengthy, very important processes leading to squalene formation were elucidated. In both animals and plants these lead to the formation of prenoids, and plants then convert these to a variety of natural products, some of which have been used successfully in medical treatment of skin and other cancers, e.g., paclitaxel (Taxol®).
Our skin synthesizes squalene, a product similar to this successful isoprenoid. We found it to inhibit mitosis without causing chromosomal aberration.
Two locations are known within the complex poly-layer structure of skin: at the base in fat skin cells, and on the surface as extruded layers. The surface-located squalene directly absorbs UV, being thus responsible for protection against the sun’s radiation with minimal damage if free radicals have been released, because the reaction occurs only on the surface and not within the skin. It would be beneficial to form an additional layer with squalene contained in a gel or cream, as a sun screen layer. It would be especially beneficial after bathing, which removes squalene naturally deposited on the skin.
The second, even larger concentration of squalene is located under the basal skin within the fat cells. After absorbing UV within the cells, squalene itself has the potential for conversion to a free radical, but within the cell glutathione would be responsible for restoration of reduced squalene from its oxidized form. Glutathione is the ultimate antioxidant and detoxifier, and in the same way it reduces oxidized vitamin C after it has itself acted as an antioxidant.
Other natural products (phenolic compounds) e.g., bioflavonoids and couma-rins from the diet, may play a role as co-operating antioxidants with squalene and glutathione, because they contain hydroxyl groups attached to a benzene ring, which arrangement allows UV absorption.
We are currently conducting experiments on the reaction of squalene in cells with natural levels of different minerals and those deprived of some minerals such as selenium, magnesium, potassium, silicon and boron.
Alicja Zobel, Institute of Spectrosocopy, Trent University, Peterborough, Ontario, Canada K9J 7B8. Telephone 705 745-6074. E-mail firstname.lastname@example.org.
Dr Alicja Zobel