title: Changes in spectral properties and composition of lipofuscin fluorophores from human-retinal-pigment epithelium with age and pathology.
abstract: Fundus autofluorescence mostly originates from bisretinoid fluorophores in lipofuscin granules, which accumulate in retinal-pigment-epithelium cells with age. The dynamics of accumulation, photo-oxidation, and photodegradation of bisretinoids during aging or in the presence of pathology have been insufficiently investigated. Changes in spectral properties and composition of human lipofuscin-granule fluorophores with age and pathology have now been investigated by a high-performance liquid chromatography method using spectrophotometric and fluorescent detectors connected in series. It was found that: (i) N-retinylidene-N-retinylethanolamine (A2E) fluorescence intensity is not predominant in the chloroform extract of human-cadaver-eye retinal pigment epithelium studied; bisretinoid photo-oxidation and photodegradation products have much higher fluorescent properties; (ii) the relative emission maximum in the fluorescence spectrum of suspended retinal-pigment-epithelium cells obtained from an individual human-cadaver eye without pathology is irrespective of donor age and falls within the range 575 ± 15 nm; in two cadaver eyes with signs of age-related macular degeneration, emission maxima were shifted by 23-36 nm towards the shortwave region; and (iii) the ratio of bisretinoid photo-oxidation and photodegradation products to unoxidized bisretinoids in the chloroform extract of cadaver-eye retinal pigment epithelium increases with donor age, from 0.69 ± 0.03 to 1.32 ± 0.04. The differences in fluorescence properties between chloroform extracts obtained from cadaver eyes with and without signs of age-related macular degeneration could be used to increase the potential of fundus autofluorescence imaging as a noninvasive diagnostic method.
authors.affiliation: Department of Molecular Physiology, Biological Faculty, Lomonosov Moscow State University, Leninskie Gory1, Moscow, 119991, Russia, feldmantb@mail.ru.
authors.forename: Tatiana B
authors.initials: TB
authors.lastname: Feldman
authors.forename: Marina A
authors.initials: MA
authors.lastname: Yakovleva
authors.forename: Patimat M
authors.initials: PM
authors.lastname: Arbukhanova
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Borzenok
authors.forename: Alexey S
authors.initials: AS
authors.lastname: Kononikhin
authors.forename: Igor A
authors.initials: IA
authors.lastname: Popov
authors.forename: Evgeny N
authors.initials: EN
authors.lastname: Nikolaev
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Ostrovsky
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism* / Q000473:pathology*; D002102:Cadaver; D002851:Chromatography, High Pressure Liquid; D005456:Fluorescent Dyes; D006801:Humans; D008062:Lipofuscin / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects; D008875:Middle Aged; D008954:Models, Biological; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D055213:Retinal Pigment Epithelium / Q000378:metabolism* / Q000473:pathology*; D012176:Retinoids / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects; D055815:Young Adult
chemical_list: C112040:A2-E (N-retinylidene-N-retinylethanolamine); D005456:Fluorescent Dyes; D008062:Lipofuscin; D012176:Retinoids