Allergan, an AbbVie company, Irvine, California, USA.
Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, Kentucky, USA.
J Ocul Pharmacol Ther. 2024 Nov;40(9):562-570. doi: 10.1089/jop.2024.0063. Epub 2024 Aug 16.
Changes in meibum composition and quantity in meibomian gland dysfunction (MGD) result in tear film instability and dry eye. This exploratory study aimed to identify changes in (O-acyl)-ω-hydroxy fatty acid (OAHFA) and hydrocarbon chain (HC) unsaturation levels in meibum related to the presence and severity of MGD. Meibum samples were collected from 3 cohorts of adults with no MGD, mild-to-moderate MGD, and severe MGD in a noninterventional clinical trial (NCT01979887). OAHFAs, cholesterol esters (CE), HC unsaturation, and HC length in the meibum samples were quantified with H-nuclear magnetic resonance spectroscopy using 2 methods of normalization. Meibum samples from 62 subjects were analyzed: 21 non-MGD, 21 mild-to-moderate MGD, and 20 severe MGD. Meibum OAHFA and CE levels and HC unsaturation were reduced with increasing severity of MGD, with most pairwise comparisons significant ( < 0.05, -tests), following the order non-MGD > mild-to-moderate MGD > severe MGD. Regardless of the resonances used for normalization, each pairwise comparison of OAHFA, CE, and HC unsaturation levels in MGD (combined severities) versus non-MGD samples was significant ( < 0.01, -test). Analysis using various normalization equations showed reductions of 20%-22% for OAHFAs, 51%-57% for CE, and 36%-66% for HC unsaturation in MGD (combined severities) compared with non-MGD. HC length was not altered in MGD (combined severities) compared with non-MGD samples (-test). Meibum OAHFA, CE, and HC unsaturation levels were reduced in MGD and were lowest in the severe MGD cohort. These findings may contribute to the understanding of the pathophysiology of MGD.
睑板腺功能障碍 (MGD) 会导致睑脂成分和数量改变，从而引起泪膜不稳定和干眼。本探索性研究旨在确定与 MGD 存在和严重程度相关的睑脂中 (O-酰基)-ω-羟基脂肪酸 (OAHFA) 和烃链 (HC) 不饱和度的变化。 在一项非干预性临床试验 (NCT01979887) 中，从无 MGD、轻中度 MGD 和重度 MGD 的三组成年人中采集了睑脂样本。使用 H 核磁共振波谱法，通过 2 种归一化方法对睑脂样本中的 OAHFAs、胆固醇酯 (CE)、HC 不饱和度和 HC 长度进行定量。 共分析了 62 名受试者的睑脂样本：21 名无 MGD、21 名轻中度 MGD 和 20 名重度 MGD。随着 MGD 严重程度的增加，睑脂 OAHFA 和 CE 水平以及 HC 不饱和度降低，大多数两两比较有统计学意义（<0.05，t 检验），顺序为无 MGD>轻中度 MGD>重度 MGD。无论使用哪种共振进行归一化，MGD（综合严重程度）与非 MGD 样本之间的 OAHFA、CE 和 HC 不饱和度水平的每一对比较均有统计学意义（<0.01，t 检验）。使用各种归一化方程进行的分析显示，MGD（综合严重程度）与非 MGD 相比，OAHFAs 降低了 20%-22%，CE 降低了 51%-57%，HC 不饱和度降低了 36%-66%。与非 MGD 样本相比，MGD（综合严重程度）中 HC 长度没有改变（t 检验）。 MGD 中睑脂 OAHFA、CE 和 HC 不饱和度降低，且在重度 MGD 组中最低。这些发现可能有助于理解 MGD 的病理生理学。
