Age-Related Changes in RPE Lipofuscin Lead to Hydrophobic Polymers

Abstract

AbstractThe accumulation of lipofuscin has been shown to precede the death of photoreceptor cells and the RPE in degenerative diseases of the retina. One of the components of lipofuscin, A2E, is known to have a mass of 592 Da. Most remaining chromophores in RPE lipofuscin are structurally related to A2E as determined by their fragmentation pattern with losses of 106, 190, 174, and/or 150 amu from the parent ion and the formation of fragments of circa 592 amu. Analysis of lipofuscin indicates that lipofuscin consists of as many as 15 hydrophobic components, consisting of circa 90% of the A2E-like components in the organic soluble RPE lipofuscin and correspond to derivatized A2E with discrete molecular weights of 800–900, 970–1,080 m/z and above 1,200 m/z regions. These species are formed from self reaction of A2E oxidation products or their reaction with A2E itself to form higher molecular weight products.KeywordsRetinal Pigment EpitheliumFragmentation PatternRetinal Pigment Epithelium CellCollision Induce DissociationPhosphatidyl EthanolamineThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.