Free fatty acids and fatty acids of triacylglycerols in normal and hyperkeratotic human stratum corneum.

The content of the free fatty acids and the fatty acids of triacylglycerols has been measured in human plantar stratum corneum from normal and hyperkeratotic subjects with palmoplantar keratoderma. Fatty acids of triacylglycerols in normal tissues showed a characteristic pattern with a relative abundance of short-chain length and unsaturated fatty acids. Free fatty acid fraction was characterized by the predominance of saturated compounds. The relative amount of short-chain and monoene fatty acids in the hyperkeratotic stratum corneum was increased. These results seem to show a defect in the maturation of fatty acids in the living epidermis and present new evidence that the abnormality of lipid metabolism can influence the process of desquamation in stratum corneum.