ABSTRACT
Phosphatidylcholine (PC) is the most abundant phospholipid in animal cells. It possesses an intrinsic hydration force, and its metabolites are essential osmoprotectants. Phosphatidylcholine composed of saturated fatty acids (hydrogenated PC; HPC) possesses physical properties which are comparable with those of the components of the skin permeability barrier. When applied to skin, HPC is taken up by the stratum corneum (SC); it interacts with lipids of the permeability barrier, but it does not cause any irritation. Phosphatidylcholine, HPC, and their metabolites display preventive efficacy in pathological states caused by the redox imbalance and the ensuing genesis of free radicals. This phenomenon is taken advantage of in the drug formulations where PC ameliorates certain side effects of drugs. In human skin challenged by sodium lauryl sulfate (SLS), HPC increases skin hydration, but does not exhibit any effect on the trans-epidermal water loss (TEWL). In addition, HPC has the ability to counteract the inflammatory effects of SLS. And HPC is an industrially available, easy-to-handle and well-defined substance produced according to the cGMP standards. The favorable biological effects inspire a new approach to the development of topical formulations for the treatment and prevention of frequent skin problems connected with dry skin and the ensuing pathological states.
