title: Lipidomic analysis of human tear fluid reveals structure-specific lipid alterations in dry eye syndrome.
abstract: As current diagnostic markers for dry eye syndrome (DES) are lacking in both sensitivity and specificity, a pressing concern exists to develop activity markers that closely align with the principal axes of disease progression. In this study, a comprehensive lipidomic platform designated for analysis of the human tear lipidome was employed to characterize changes in tear lipid compositions from a cohort of 93 subjects of different clinical subgroups classified based on the presence of dry eye symptoms and signs. Positive correlations were observed between the tear levels of cholesteryl sulfates and glycosphingolipids with physiological secretion of tears, which indicated the possible lacrimal (instead of meibomian) origin of these lipids. Notably, we found wax esters of low molecular masses and those containing saturated fatty acyl moieties were specifically reduced with disease and significantly correlated with various DES clinical parameters such as ocular surface disease index, tear breakup time, and Schirmer's I test (i.e., both symptoms and signs). These structure-specific changes in tear components with DES could potentially serve as unifying indicators of disease symptoms and signs. In addition, the structurally-specific aberrations in tear lipids reported here were found in patients with or without aqueous deficiency, suggesting a common pathology for both DES subtypes.
authors.affiliation: State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Sin Man
authors.initials: SM
authors.lastname: Lam
authors.forename: Louis
authors.initials: L
authors.lastname: Tong
authors.forename: Bastien
authors.initials: B
authors.lastname: Reux
authors.forename: Xinrui
authors.initials: X
authors.lastname: Duan
authors.forename: Andrea
authors.initials: A
authors.lastname: Petznick
authors.forename: Siew Sian
authors.initials: SS
authors.lastname: Yong
authors.forename: Cynthia Boo Shiao
authors.initials: CB
authors.lastname: Khee
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Lear
authors.forename: Markus R
authors.initials: MR
authors.lastname: Wenk
authors.forename: Guanghou
authors.initials: G
authors.lastname: Shui
mesh_terms: D015352:Dry Eye Syndromes / Q000378:metabolism* / Q000503:physiopathology; D005227:Fatty Acids / Q000737:chemistry; D006801:Humans; D050356:Lipid Metabolism; D008055:Lipids / Q000737:chemistry*; D008537:Meibomian Glands / Q000378:metabolism / Q000503:physiopathology; D008970:Molecular Weight; D013666:Tears / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D008055:Lipids
keywords: mass spectrometry; meibum; tear lipidome; wax esters