Age-related antioxidant capacity of the vitreous and its possible relationship with simultaneous changes in photoreceptors, retinal pigment epithelium and Bruchs' membrane in human donors' eyes

It is well established that the retina undergoes several decremental functional and structural changes with age, and it has been suggested that most of these age-related changes may be mainly due to oxidative stress through light-induced mechanisms. While the cornea and the lens absorb part of the light radiation, the vitreous appears to be the main site of protection against radiation damage to the retina. Thus the purpose of this study was to explore possible interrelationships between the oxidative capacity of the vitreous and the number of photoreceptors, the fluorescent intensity of the retina, and the thickness of the Bruch's membrane in eyes from donors dying from the third to the eighth decade of life. The results showed that the total reactive antioxidant potential of the vitreous significantly decreased with the age of the donor's eyes, and that this decrease was directly correlated with decreases in the photoreceptors and inversely correlated with increases in the autofluorescent intensity of the retina and the thickness of the Bruch's membrane. Although these correlations did not prove a cause-effect relationship, these findings may provide new insights for the understanding and possible treatment of the age-dependent changes of the human eyes.