Imokawa G, Abe A, Jin K, Higaki Y, Kawashima M, Hidano A
Tochigi Research Laboratories, Kao Corporation, Japan.
J Invest Dermatol. 1991 Apr;96(4):523-6. doi: 10.1111/1523-1747.ep12470233.
Stratum corneum lipids are an important determinant for both water-retention function and permeability-barrier function in the stratum corneum. However, their major constituent, ceramides, have not been analyzed in detail in skin diseases such as atopic dermatitis that show defective water-retention and permeability-barrier function. In an attempt to assess the quantity of ceramides per unit mass of the stratum corneum in atopic dermatitis, stratum corneum sheet was removed from the forearm skin by stripping with cyanoacrylate resin and placed in hexane/ethanol extraction to yield stratum corneum lipids. The stratum corneum was dispersed by solubilization of cyanoacrylate resin with dimethylformamide, and after membrane filtration, the weight of the stratum corneum mass was measured. The ceramides were quantified by thin-layer chromatography and evaluated as microgram/mg stratum corneum. In the forearm skin of healthy individuals (n = 65), the total ceramide content significantly declined with increasing age. In atopic dermatitis (n = 32-35), there was a marked reduction in the amount of ceramides in the lesional forearm skin compared with those of healthy individuals of the same age. Interestingly, the non-lesional skin also exhibited a similar and significant decrease of ceramides. Among six ceramide fractions, ceramide 1 was most significantly reduced in both lesional and non-lesional skin. These findings suggest that an insufficiency of ceramides in the stratum corneum is an etiologic factor in atopic dry skin.
角质层脂质是角质层中保水功能和渗透屏障功能的重要决定因素。然而，它们的主要成分神经酰胺，在诸如特应性皮炎这类表现出保水和渗透屏障功能缺陷的皮肤疾病中尚未得到详细分析。为了评估特应性皮炎患者角质层单位质量中神经酰胺的含量，通过用氰基丙烯酸酯树脂剥离从前臂皮肤获取角质层薄片，并将其置于己烷/乙醇提取物中以得到角质层脂质。通过用二甲基甲酰胺溶解氰基丙烯酸酯树脂来分散角质层，经过膜过滤后，测量角质层物质的重量。通过薄层色谱法定量神经酰胺，并以微克/毫克角质层来评估。在健康个体（n = 65）的前臂皮肤中，总神经酰胺含量随年龄增长显著下降。在特应性皮炎患者（n = 32 - 35）中，与同年龄健康个体相比，病变前臂皮肤中的神经酰胺量显著减少。有趣的是，非病变皮肤也表现出类似且显著的神经酰胺减少。在六个神经酰胺组分中，神经酰胺1在病变和非病变皮肤中减少最为显著。这些发现表明角质层中神经酰胺不足是特应性干性皮肤的一个病因。
