皮膚バリア機能とその制御 : 表皮構造の観点から Skin barrier function and its regulation in terms of epidermal molecular structure

皮膚の水・空気環境バリア機能に関して最も重要な構造は，角質細胞間にある脂質多重層構造である．これを恒常的に構築する細胞が表皮ケラチノサイトであり，その最終分化細胞の角質細胞は強靱な細胞シート構造を保ち，脂質多重層を柔軟に強く保持している．そのために，ケラチノサイトは細胞内にはケラチン中間径線維とデスモソーム，アドヘレンスジャンクション（Jnc），タイトJnc，ギャップJncなどの細胞接着構造を発達させている．その分子変異や機能異常は角化異常とバリア機能不全をきたす．これらの分子の制御はDDSの制御につながる．

The most important structure for the maintenance of epidermal barrier function between air and water environments is the lipid lamellar layer in the stratum corneum (StC). It is epidermal keratinocytes that generate this lipid layer and maintain it in StC, which is in tern generated by keratinization of keratinocytes. To hold lipid layers in StC in a flexible and stead way, keratinocytes integrate different junctions, as such desmosome, tight, gap and adherens, desmosome and adherens junction of which are associated with cytoskeletons, into the epidermal sheet and these junctions regulate keratinaization. The molecular defects of these junctions and keratinization exert impairments of epidermal barrier function. The control of these molecules may provide us with a clue for the control of DDS.