Photosensitizing Activity of Endogenous Eye Lens Chromophores: An Attempt to Unravel Their Contributions to Photo-Aging and Cataract Disease.
UVA-visible light has been proposed as a risk factor in the photo-aging of the human eye lens, as well as in the etiology of cataract disease. There is accumulating evidence indicating that photosensitizing reactions mediated by endogenous chromophores, which are generated during human eye lens aging, can play an important role in the generation of these processes. These reactions can lead to protein impairment by inducing non-enzymatic post-translational modifications such as protein oxidation and crosslinking. Although numerous chromophores have been characterized as both bound to human eye lens proteins and as unbound low-molecular-mass compounds, their contribution to eye lens photoaging and cataract disease is not completely understood. In this article we discuss the photochemical contribution of UV-filters derived from tryptophan catabolism and advanced glycation end products (AGEs) to human eye lens aging and cataract disease. We also discuss the recently described photosensitizing capacity of chromophores derived from newly discovered glucose and ascorbate degradation as a parallel pathway to their role in AGEs generation.
Escuela de Nutrición y Dietética, Facultad de Ciencias de la Salud, Universidad de Talca, Talca, Chile.|Programa de Investigación de Excelencia Interdisciplinario en Envejecimiento Saludable (PIEI-ES), Universidad de Talca, Talca, Chile.
Felipe
F
Avila
UPMC Univ. Paris 06, CNRS UMR 8256, INSERM U1164, Adaptation Biologique et Vieillissement, Institute of Biology Paris-Seine, Paris, France.
Bertrand
B
Friguet
Departamento de Química Física, Facultad de Química, Pontifícia Universidad Católica de Chile, Santiago, Chile.
Eduardo
E
Silva
D000375:Aging / Q000473:pathology*; D002386:Cataract / Q000209:etiology*; D006801:Humans; D007908:Lens, Crystalline / Q000187:drug effects*; D017319:Photosensitizing Agents / Q000494:pharmacology*
D017319:Photosensitizing Agents