BK21 Plus KNU Multi-Omics Based Creative Drug Research Team, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, 80 Deahak-ro, Buk-gu, Daegu, 41566, Korea.
Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin, 17104, Korea.
Arch Pharm Res. 2016 Oct;39(10):1426-1432. doi: 10.1007/s12272-016-0794-9. Epub 2016 Jul 18.
The stratum corneum (SC) acts as a barrier that protects organisms against the environment and from transepidermal water loss. It consists of corneocytes embedded in a matrix of lipid metabolites (ceramides, cholesterol, and free fatty acids). Of these lipids, ceramides are sphingolipids consisting of sphingoid bases, linked to fatty acyl chains. Typical fatty acid acyl chains are composed of α-hydroxy fatty acids (A), esterified ω-hydroxy fatty acids (EO), non-hydroxy fatty acids (N), and ω-hydroxy fatty acids (O). Of these, O-type ceramides are ester-linked via their ω-hydroxyl group to proteins in the cornified envelope and can be released and extracted following mild alkaline hydrolysis. Tandem mass spectrometry (MS/MS) analysis of O-type ceramides using chip-based direct infusion nanoelectrospray-ion trap mass spectrometry generated the characteristic fragmentation pattern of both acyl and sphingoid units, suggesting that this method could be applied to the structural identification of O-type ceramides. Based on the MS/MS fragmentation patterns of O-type ceramides, comprehensive fragmentation schemes are proposed. In addition, we have also developed a method for identifying and profiling O-type ceramides in the mouse and guinea pig SC. This information may be used to identify O-type ceramides in the SC of animal skin.
角质层（SC）作为一种屏障，保护生物体免受环境和经表皮水分流失的影响。它由嵌入在脂质代谢物（神经酰胺、胆固醇和游离脂肪酸）基质中的角质细胞组成。在这些脂质中，神经酰胺是由鞘氨醇碱基与脂肪酸酰基链连接而成的鞘脂。典型的脂肪酸酰基链由α-羟基脂肪酸（A）、酯化的ω-羟基脂肪酸（EO）、非羟基脂肪酸（N）和ω-羟基脂肪酸（O）组成。其中，O 型神经酰胺通过其ω-羟基与角蛋白包膜中的蛋白质以酯键相连，可在温和的碱性水解后释放和提取。使用基于芯片的直接进样纳升电喷雾离子阱质谱联用技术对 O 型神经酰胺进行串联质谱（MS/MS）分析，产生了酰基和鞘氨醇单元的特征碎片模式，表明该方法可应用于 O 型神经酰胺的结构鉴定。基于 O 型神经酰胺的 MS/MS 碎片模式，提出了全面的碎裂方案。此外，我们还开发了一种用于鉴定和分析小鼠和豚鼠 SC 中 O 型神经酰胺的方法。这些信息可用于鉴定动物皮肤 SC 中的 O 型神经酰胺。
