A2E Distribution in RPE Granules in Human Eyes.
Journal Article (Journal Article)
A2E (N- retinylidene-N- retinylethanolamine) is a major fluorophore in the RPE (retinal pigment epithelium). To identify and characterize A2E-rich RPE lipofuscin, we fractionated RPE granules from human donor eyes into five fractions (F1-F5 in ascending order of density) by discontinuous sucrose density gradient centrifugation. The dry weight of each fraction was measured and A2E was quantified by liquid chromatography/mass spectrometry (LC/MS) using a synthetic A2E homolog as a standard. Autofluorescence emission was characterized by a customer-built spectro-fluorometer system. A significant A2E level was detected in every fraction, and the highest level was found in F1, a low-density fraction that makes up half of the total weight of all RPE granules, contains 67% of all A2E, and emits 75% of projected autofluorescence by all RPE granules. This group of RPE granules, not described previously, is therefore the most abundant RPE lipofuscin granule population. A progressive decrease in autofluorescence was observed from F2 to F4, whereas no autofluorescence emission was detected from the heavily pigmented F5. The identification of a novel and major RPE lipofuscin population could have significant implications in our understanding of A2E and lipofuscin in human RPE.
Full Text
Duke Authors
Cited Authors
- Guan, Z; Li, Y; Jiao, S; Yeasmin, N; Rosenfeld, PJ; Dubovy, SR; Lam, BL; Wen, R
Published Date
- March 20, 2020
Published In
Volume / Issue
- 25 / 6
Start / End Page
- E1413 -
PubMed ID
- 32244898
Pubmed Central ID
- PMC7144568
Electronic International Standard Serial Number (EISSN)
- 1420-3049
International Standard Serial Number (ISSN)
- 1420-3049
Digital Object Identifier (DOI)
- 10.3390/molecules25061413
Language
- eng