Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Exp Med. Nov 20, 2016; 6(4): 63-71
Published online Nov 20, 2016. doi: 10.5493/wjem.v6.i4.63
Lipofuscins prepared by modification of photoreceptor cells via glycation or lipid peroxidation show the similar phototoxicity
Alexander Dontsov, Anna Koromyslova, Mikhail Ostrovsky, Natalia Sakina
Alexander Dontsov, Anna Koromyslova, Mikhail Ostrovsky, Natalia Sakina, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
Author contributions: All authors contributed to this manuscript.
Supported by The Russian Foundation for Basic Research, No. 15-29-03831.
Institutional review board statement: The study reviewed and approved by the Emanuel Institute of Biochemical Physics.
Institutional animal care and use committee statement: The study reviewed and approved by the Emanuel Institute of Biochemical Physics. Animals subjects were not involved in our experimental study.
Conflict-of-interest statement: The authors have no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Natalia Sakina, PhD, Senior Researcher, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygina st. 4, 119334 Moscow, Russia.
Telephone: +7-495-9397422 Fax: +7-499-1374101
Received: June 29, 2016
Peer-review started: July 1, 2016
First decision: September 5, 2016
Revised: September 19, 2016
Accepted: October 17, 2016
Article in press: October 19, 2016
Published online: November 20, 2016

To investigate the effect of two ways of lipofuscin production (lipid peroxidation and glycation) on lipofuscin fluorescence characteristics and phototoxicity and to compare them with the properties of natural lipofuscin.


Model lipofuscins were prepared on the basis of bovine photoreceptor outer segments (POS) with bisretinoid A2E addition. One set of samples was prepared from POS modified by lipid peroxidation, while another set from POS modified by glycation with fructose. Fluorescent properties and kinetics of photoinduced superoxide generation of model lipofuscins and human retinal pigment epithelium (RPE) lipofuscin were compared. The fluorescence spectra of samples were measured at 365 nm excitation wavelength and 380-650 emission wavelength.


The fluorescence spectra of model lipofuscins are almost the same as the spectrum of natural lipofuscin. Visible light irradiation of both model lipofuscins and natural lipofuscin isolated from RPE cells leads to decrease of a fluorescence maximum at 550 nm and to appearance of a distinct, new maximum at 445-460 nm. The rate of photogeneration of reactive oxygen forms by both model lipofuscins was almost the same and approximately two times less than that of RPE lipofuscin granules.


These data suggest that fluorescent characteristics and phototoxicity of lipofuscin granules depend only to an insignificant degree on the oxidative modification of POS proteins and lipids, and generally are defined by the bisretinoid fluorophores contained in them.

Keywords: Model lipofuscins, Retinal pigment epithelium, Photoreceptor outer segments, Bisretinoids, Glycation, Lipid peroxidation, Superoxide

Core tip: The aim of this work is to investigate the influence of different ways of protein-lipid modification of photoreceptor outer segments (POS) on the spectral characteristics and toxicity of lipofuscin. Therefore, model lipofuscins were prepared by protein-lipid modification of POS with products of lipid peroxidation or glycation reaction and the subsequent addition of the fluorophore A2E. The type of photoreceptor modification has no effect on model lipofuscins phototoxicity.