van Smeden Jeroen, Janssens Michelle, Kaye Edward C J, Caspers Peter J, Lavrijsen Adriana P, Vreeken Rob J, Bouwstra Joke A
Department of Drug Delivery Technology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
Exp Dermatol. 2014 Jan;23(1):45-52. doi: 10.1111/exd.12293.
An important feature of atopic eczema (AE) is a decreased skin barrier function. The stratum corneum (SC) lipids - comprised of ceramides (CERs), free fatty acids (FFAs) and cholesterol - fulfil a predominant role in the skin barrier function. In this clinical study, the carbon chain length distribution of SC lipids (FFAs and CERs) and their importance for the lipid organization and skin barrier function were examined in AE patients and compared with control subjects. A reduction in FFA chain length and an increase in unsaturated FFAs are observed in non-lesional and lesional SC of AE patients. The reduction in FFA chain length associates with a reduced CER chain length, suggesting a common synthetic pathway. The lipid chain length reduction correlates with a less dense lipid organization and a decreased skin barrier function. All changes are more pronounced in lesional SC compared with non-lesional skin. No association was observed between lipid properties and filaggrin mutations, an important predisposing factor for developing AE. The results of this study demonstrate an altered SC lipid composition and signify the importance of these changes (specifically regarding the CER and FFA chain lengths) for the impaired skin barrier function in AE. This provides insights into epidermal lipid metabolism as well as new opportunities for skin barrier repair.
特应性皮炎（AE）的一个重要特征是皮肤屏障功能下降。角质层（SC）脂质——由神经酰胺（CERs）、游离脂肪酸（FFAs）和胆固醇组成——在皮肤屏障功能中起主要作用。在这项临床研究中，研究了AE患者SC脂质（FFAs和CERs）的碳链长度分布及其对脂质组织和皮肤屏障功能的重要性，并与对照受试者进行了比较。在AE患者的非皮损和皮损SC中均观察到FFA链长度缩短和不饱和FFA增加。FFA链长度的缩短与CER链长度的缩短相关，提示存在共同的合成途径。脂质链长度的缩短与脂质组织密度降低和皮肤屏障功能下降相关。与非皮损皮肤相比，所有变化在皮损SC中更为明显。未观察到脂质特性与丝聚蛋白突变之间的关联，丝聚蛋白突变是AE发生的一个重要易感因素。这项研究的结果表明SC脂质组成发生了改变，并表明这些变化（特别是关于CER和FFA链长度）对AE中受损的皮肤屏障功能具有重要意义。这为表皮脂质代谢提供了见解，并为皮肤屏障修复提供了新的机会。
