6533b829fe1ef96bd1289b04

RESEARCH PRODUCT

Comparative study of serine-plasmalogens in human retina and optic nerve: identification of atypical species with odd carbon chains

subject

description

International audience; The objective of this work was to detect and identify phosphatidylserine plasmalogen species in human ocular neurons represented by the retina and the optic nerve. Plasmalogens (vinyl-ether bearing phospholipids) are commonly found in the forms of phosphatidylcholine and phosphatidylethanolamine in numerous mammalian cell types, including the retina. While their biological functions are still unclear, the alteration of cellular plasmalogen content has been associated with several human disorders such as Rhizomelic Chondrodysplasia Punctata Type 2 and Primary Open-Angle Glaucoma.By using liquid-chromatography coupled to high resolution and tandem mass spectrometry, we have identified for the first time several species of phosphatidylserine plasmalogens including atypical forms having moieties with odd numbers of carbons and unsaturation in sn-2 position. Structural elucidation of the potential phosphatidylserine ether linked species was pursued by performing MS3 experiments and three fragments are proposed as marker ions to deduce which fatty acid is linked as ether or ester on the glycerol backbone. Interpretation of the fragmentation patterns based on this scheme enabled the assignment of structures to the m/z values this way identifying the phosphatidylserine plasmalogens.