Identification and Role of Non-Sebaceous Keratin Lipids in Skin

摘要

The presence of appreciable amounts of lipid material (2.7 to 9.1%) in both normal and pathological horny layer material was confirmed. The lipid occurred both as free lipids and as protein-lipid complexes, and two types of lipids were recognized. One can be removed from the horny layer by extraction with alcohol, while the latter requires more drastic extraction procedures. Both lipids are exceedingly complex in nature. Three major groups of proteolipids were demonstrated in the alcohol-soluble lipids, one of which consists of sterol-proteolipids. At least ten different proteolipids are believed to be present. On hydrolysis the mixed proteolipids yielded free fatty acids, free sterols, phosphatides, hydrocarbons, waxes, sterol esters and triglycerides. No definite chemical structure can yet be assigned to any of these proteolipids. Differences were observed in the nature of the horny layer lipids in certain scaly dermatoses. It is considered that these differences are related to the loss of barrier function of the skin in such conditions. It is believed that these proteolipids play an essential role in the keratinization process and in the barrier function of normal skin. (Author)