UV mediated DNA damage measured in keratoconus, graft failure and healthy corneas

Session Details

Session Title: Cross-Linking

Session Date/Time: Sunday 11/09/2016 | 08:00-09:30

Paper Time: 08:38

Venue: Auditorium A

First Author: : R.Wisse THE NETHERLANDS

Co Author(s): :    J. Kuiper   T. Radstake   S. Imhof   A. van der Lelij   J. Broen        

Abstract Details

Purpose:

Keratoconus (KC) is a disease of the cornea that can lead to a severe decrease in visual acuity and may warrant performing a corneal graft. The pathogenesis of KC is considered to be multifactorial and is associated with oxidative stress. Both oxidative stress and ultraviolet (UV) light can cause DNA damage, and UV light has been implicated in the corneal pathology associated with KC. Therefore, the aim of this study was to investigate DNA damage in corneas with KC and in control corneas.

Setting:

Academic tertiary hospital UMC Utrecht

Methods:

Corneal buttons were obtained from 12 patients with KC who were undergoing corneal transplant surgery, 11 patients with a decompensated graft (DG) not related to KC, and 10 unaffected (healthy) post-mortem donor corneas (HC). Total DNA was extracted from the corneal buttons, and the number of intact Alu elements per genome copy was measured using qPCR and was used quantify intact DNA.

Results:

Mean (±SD) DNA damage was similar between the KC (0.022 ± 0.030), DG (0.026 ± 0.053), and HC (0.011 ± 0.012) groups (P=0.719). No association was found between DNA damage and patient age (P=0.780), atopic constitution (P=0.495), or contact lens wear (P=0.452). Interestingly, one patient with KC in our study underwent an epithelium-off corneal crosslinking procedure with UV-A irradiation three years prior to the grafting procedure, and this patient had a 100-fold higher level of DNA damage compared with the other samples.

Conclusions:

In conclusion, corneal DNA damage did not differ between the study groups. Thus, corneal DNA damage does not appear to be a major etiological factor in the pathogenesis of KC. UV crosslinking might induce substantial DNA damage in the relatively long-lived keratocytes of the corneal stroma.

Financial Disclosure:

NONE