Human meibum chain branching variability with age, gender and meibomian gland dysfunction. Ocul Surf 2019 Apr;17(2):327-335
Date
12/16/2018Pubmed ID
30553000Pubmed Central ID
PMC6529269DOI
10.1016/j.jtos.2018.12.005Scopus ID
2-s2.0-85058451755 (requires institutional sign-in at Scopus site) 24 CitationsAbstract
NMR spectroscopy was used to measure hydrocarbon chain branching variability in meibum with age, gender and Meibomian gland dysfuction (MGD). A cohort of 65 meibum donors without dry eye and 31 donors with MGD was studied. Heteronuclear 2D NMR was used to confirm CH3 resonance assignments allowing us to positively identify 23 of the 27 proton resonances of cholesteryl ester and 1H resonances due to straight chain, iso-branched and anteiso-branched hydrocarbons. Meibum from donors without dry eye contained 57 ± 1% straight-chains, 23 ± 1% iso-branched chains and 20 ± 1% anteiso-branched hydrocarbon chains. Compared with meibum from donors without dry eye, meibum from donors with MGD contained less, 50 ± 2% straight-chains, more, 32 ± 2% iso-branched chains and the same amount, 18.0 ± 0.07%, of anteiso-branched hydrocarbon chains. Meibum hydrocarbon chain branching did not change with age between 22 and 68 years of age, nor was it influenced by gender. Based on previous studies, one would expect anteiso-branched chains would contribute to lowering the phase transition temperature of meibum, decrease the elasticity of the tear film lipid layer and increase the molecular area and spreading of meibum on the surface of the eye. Although we speculate that the observed differences in iso-chain branching do not influence tear film stability or rheology, the speculation has yet to be tested.
Author List
Borchman D, Ramasubramanian AAuthor
Aparna Ramasubramanian MD Chief, Associate Professor in the Ophthalmology and Visual Sciences department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdolescentAdult
Aged
Aged, 80 and over
Aging
Biomarkers
Child
Child, Preschool
Female
Humans
Infant
Lipid Metabolism
Lipids
Magnetic Resonance Spectroscopy
Male
Meibomian Glands
Middle Aged
Tears
Young Adult
