Choe ChunSik, Lademann Jürgen, Darvin Maxim E
Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany.
Analyst. 2016 Mar 21;141(6):1981-7. doi: 10.1039/c5an02373d.
The intercellular lipid structure of the stratum corneum (SC) plays a key role in skin barrier function. A depth profile of the intercellular lipid conformation and the lipid lateral packing order were measured in vivo in the human SC using confocal Raman microscopy. The depth profiles of the 2880 cm(-1)/2850 cm(-1) peak ratio intensity, which represent the C-H stretching and lateral packing order of lipids, and the 1080 cm(-1)/(1130 cm(-1) + 1060 cm(-1)) peak ratio, which represents the C-C skeleton vibration and trans-gauche conformation order of lipids, were investigated. The influence of keratin on the lipid peaks at 2850 cm(-1) and 2880 cm(-1) was excluded by the developed mathematical algorithm. The results show that the trans-conformation and lateral packing order of the intercellular lipids reach their maximum value in the SC at 20-40% of its depth and then decrease towards the stratum granulosum. These results show that at a depth of 20-40% (normally corresponding to a depth of 4-8 μm) the SC exhibits the most ordered lipids and therefore the highest skin barrier function. The lateral packing of lipids is more disordered on the surface and in the deeper parts of the SC, which may be associated with a reduced skin barrier function.
角质层（SC）的细胞间脂质结构在皮肤屏障功能中起关键作用。利用共聚焦拉曼显微镜在人体SC中体内测量细胞间脂质构象和脂质侧向堆积顺序的深度分布。研究了代表脂质C-H伸缩和侧向堆积顺序的2880 cm⁻¹/2850 cm⁻¹峰比强度的深度分布，以及代表脂质C-C骨架振动和顺反构象顺序的1080 cm⁻¹/（1130 cm⁻¹ + 1060 cm⁻¹）峰比。通过开发的数学算法排除了角蛋白对2850 cm⁻¹和2880 cm⁻¹处脂质峰的影响。结果表明，细胞间脂质的反式构象和侧向堆积顺序在SC深度的20%-40%处达到最大值，然后向颗粒层降低。这些结果表明，在20%-40%的深度（通常对应于4-8μm的深度），SC表现出最有序的脂质，因此具有最高的皮肤屏障功能。脂质的侧向堆积在SC的表面和更深部分更无序，这可能与皮肤屏障功能降低有关。
