Motta S, Monti M, Sesana S, Mellesi L, Ghidoni R, Caputo R
Department of Dermatology, University of Milano, Italy.
Arch Dermatol. 1994 Apr;130(4):452-6.
In psoriasis the formation of the cornified layer is deranged and water flux is reportedly increased. We investigated three different forms of psoriasis: transepidermal water loss was measured on uninvolved skin and psoriatic plaques; lipids from plaques were extracted; and ceramide distribution in scale vs normal stratum corneum was compared. Moreover, the lipid biochemical results were compared with transepidermal water loss rates in the same lesions. To assess potential alteration in ceramide distribution, lipids from both psoriatic scale and normal stratum corneum were extracted by the Bligh-Dyer method, separated on high performance thin layer chromatography plates, and quantified by computerized densitometry. Water flux was measured as transepidermal water loss using an evaporimeter; results between uninvolved and involved psoriatic skin and age-matched control skin were statistically evaluated.
In comparison with normal stratum corneum, psoriatic plaque ceramides showed a different distribution; in particular, ceramide 1 was significantly decreased. The increased transepidermal water loss values of psoriatic plaques vs control skin and between psoriatic involved vs uninvolved skin were significant.
Our findings indicate that in psoriasis the altered ceramide distribution can be linked specifically to the defect in keratinocyte differentiation; the defect in skin barrier function may be attributed largely or in part to ceramide 1 reduction.
在银屑病中，角质层的形成紊乱，且据报道水分通量增加。我们研究了三种不同类型的银屑病：测量了非病变皮肤和银屑病斑块的经表皮水分流失；提取了斑块中的脂质；并比较了鳞屑与正常角质层中神经酰胺的分布。此外，将脂质生化结果与相同皮损中的经表皮水分流失率进行了比较。为了评估神经酰胺分布的潜在变化，采用布莱-戴尔法提取银屑病鳞屑和正常角质层中的脂质，在高效薄层色谱板上进行分离，并通过计算机密度测定法进行定量。使用蒸发仪将水分通量测量为经表皮水分流失；对非病变和病变的银屑病皮肤以及年龄匹配的对照皮肤之间的结果进行统计学评估。
与正常角质层相比，银屑病斑块中的神经酰胺分布不同；特别是，神经酰胺1显著减少。银屑病斑块与对照皮肤之间以及银屑病病变皮肤与非病变皮肤之间经表皮水分流失值的增加具有显著性。
我们的研究结果表明，在银屑病中，神经酰胺分布的改变可能与角质形成细胞分化缺陷特异性相关；皮肤屏障功能缺陷可能主要或部分归因于神经酰胺1的减少。
