Plasmalogen (Pls) is a glycerophospholipid derived from alkyl phospholipid (Alk) with antioxidant functions in vivo. The present study investigated the effects of ether phospholipids, such as Pls and Alk, on intercellular lipid barriers in the skin of NC/Nga mice, a model of atopic dermatitis (AD). NC/Nga mice fed Alk showed increased plasma levels of Alk and Pls. The AD-related changes in ceramide composition in the skin were abrogated by oral administration of Alk. Moreover, Alk suppressed skin inflammation in AD mice. These results indicate that Alk partially fortifies the stratum corneum lipid barrier and may be an effective treatment for AD. Abbreviations: Pls: plasmalogen; PlsCho: choline plasmalogen; PlsEtn: ethanolamine plasmalogen; Alk: alkyl phospholipid; TJ: tight junction; FA: fatty acid; AD: atopic dermatitis; SO: soybean oil; FO: fish oil; DHA: docosahexaenoic acid; EPA: eicosapentaenoic acid; TG: triglyceride; PL: phospholipid; RF: retention factor; AlkCho: choline-type alkyl phospholipid; AlkEtn: ethanolamine-type alkyl phospholipid; LC-MS/MS: liquid chromatography-tandem mass spectrometry; FAR1: fatty acyl-coenzyme (Co)A reductase 1.
Keywords: Atopic dermatitis; alkyl phospholipid; plasmalogen; skin lipid barrier; tight junction.