Phase separation in ceramide[NP] containing lipid model membranes: neutron diffraction and solid-state NMR.
Phase separation in ceramide[NP] containing lipid model membranes: neutron diffraction and solid-state NMR.
复制标题
含有脂质模型膜的神经酰胺 [NP] 中的相分离：中子衍射和固态 NMR
作者：
A. Schroeter;S. Stahlberg;B. Školová;S. Sonnenberger;A. Eichner;D. Huster;K. Vávrová;T. Hauß;B. Dobner;R. H.H. Neubert;A. Vogel
角质层是皮肤的最外层，保护生物体免受外部影响以及水分流失。它由包埋在神经酰胺、脂肪酸和胆固醇的混合物中的角质细胞组成，其摩尔比约为1：1：1。 这些角质层脂质的独特结构和组成排列是皮肤屏障性质的原因。许多研究调查了这些屏障脂质的组织，特别是神经酰胺的确切构象。但是，迄今尚未达成共识。在这项研究中，我们使用中子衍射和2H固态NMR光谱在25 ° C至80 ° C的温度下研究了由1：1：1摩尔比的N-（非羟基二十四烷酰基）-植物鞘氨醇/胆固醇/二十四烷酸（CER [NP]-C24/CHOL/TA）组成的模型系统。 模型系统的所有三种脂质组分的氘代变体用于使它们能够在NMR光谱中进行单独的研究并定量每个相中的分子量。中子散射实验表明，在32 ° C的生理皮肤温度下，两种脂质相在低温下共存，重复间距为54.2 μ m和43.0 μ m。它们在2H NMR光谱中似乎是不可区分的，因为两相都是结晶的，并且神经酰胺分子在微秒时间尺度上不围绕其长轴旋转。这些阶段的加热后的演变，并随着温度的升高流体，甚至各向同性移动的分子观察。提出了层状相的组织模型，其中较厚的相由CER [NP]-C24以发夹构象与CHOL和TA混合组成，而重复间距为43.0 μ m的相包含CER [NP]-C24以V形构象。
The stratum corneum is the outermost layer of the skin and protects the organism against external influences as well as water loss. It consists of corneocytes embedded in a mixture of ceramides, fatty acids, and cholesterol in a molar ratio of roughly 1 : 1 : 1. The unique structural and compositional arrangement of these stratum corneum lipids is responsible for the skin barrier properties. Many studies investigated the organization of these barrier lipids and, in particular, the exact conformation of ceramides. However, so far no consensus has been reached. In this study, we investigate a model system comprised of N-(non-hydroxy-tetracosanoyl)-phytosphingosine/cholesterol/tetracosanoic acid (CER[NP]-C24/CHOL/TA) at a 1 : 1 : 1 molar ratio using neutron diffraction and 2H solid-state NMR spectroscopy at temperatures from 25 °C to 80 °C. Deuterated variants of all three lipid components of the model system were used to enable their separate investigation in the NMR spectra and quantification of the amount of molecules in each phase. Neutron scattering experiments show the coexistence of two lipid phases at low temperatures with repeat spacings of 54.2 Å and 43.0 Å at a physiological skin temperature of 32 °C. They appear to be indistinguishable in the 2H NMR spectra as both phases are crystalline and ceramide molecules do not rotate around their long axis on a microsecond timescale. The evolution of these phases upon heating is followed and with increasing temperature fluid and even isotropically mobile molecules are observed. A model of the organization of the lamellar phases is proposed in which the thicker phase consists of CER[NP]-C24 in a hairpin conformation mixed with CHOL and TA, while the phase with a repeat spacing of 43.0 Å contains CER[NP]-C24 in a V-shape conformation.
登录
查看更多内容
通过 2H 固态核磁共振波谱探讨神经酰胺头基极性在短链模型皮肤屏障脂质混合物中的作用
DOI：
10.1021/acs.langmuir.5b04173
发表时间：
2023
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
--
作者：
S. Stahlberg;S. Lange;B. Dobner;D. Huster
通讯作者：
D. Huster
通过中子衍射对角质层脂质模型膜的结构和水合作用的新见解
DOI：
--
发表时间：
2005
期刊：
European Biophysics Journal
影响因子：
--
作者：
M. Kiselev;N. Ryabova;A. Balagurov;S. Dante;T. Hauß;J. Zbytovská;S. Wartewig;R. Neubert
通讯作者：
R. Neubert
影响因子：
5.8
作者：
Rowat, AC;Kitson, N;Thewalt, JL
通讯作者：
Thewalt, JL
振动光谱和显微成像：比较天然皮肤和人类皮肤等效物的屏障物理特性的新方法
影响因子：
3.5
作者：
Guo Yu;Guojin Zhang;C. Flach;R. Mendelsohn
通讯作者：
R. Mendelsohn
影响因子：
3.4
作者：
Engelbrecht, Tanja N.;Schroeter, Annett;Neubert, Reinhard H. H.
通讯作者：
Neubert, Reinhard H. H.