Levels of Plasma 8-Hydroxy-2'-Deoxyguanosine—A Marker of Oxidative DNA Damage—Are Not Associated with Primary Angle-closure Glaucoma
Altaf A. Kondkar *
Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia, Glaucoma Research Chair, College of Medicine, King Saud University, Riyadh, Saudi Arabia and King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia.
*Author to whom correspondence should be addressed.
Abstract
Aim: The study aimed to estimate plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, a marker of oxidative deoxyribonucleic acid (DNA) damage, and evaluate their potential association with primary angle-closure glaucoma (PACG) and related clinical markers.
Study Design: This is retrospective case-control study.
Place and Duration: The study was performed on samples recruited from King Abdulaziz University Hospital, Riyadh, Saudi Arabia between August 2018 through September 2019 in the participants of Saudi origin.
Methodology: Plasma 8-OHdG levels were measured in duplicates using automated ELISA analyzer in 43 PACG patients and 45 non-glaucomatous controls.
Results: The mean levels of 8-OHdG were 13.59 ng/mL [±4.50] in PACG patients compared to 16.95 ng/mL [±10.66] in controls. The differences did not achieve statistical significance (P = 0.06). Similarly, no significant differences (P = 0.42) were observed in the median levels of 8-OHdG between PACG and controls. Furthermore, except for sex, where males exhibited a significant negative correlation (R = -0.35, P = 0.02), there was no significant correlation between 8-OHdG levels and age (P = 0.85), intraocular pressure (P = 0.58), cup/disc ratio (P = 0.39) and number of antiglaucoma medications (P = 0.41) in the PACG group. Regression analysis showed no significant influence of age, sex, and 8-OHdG levels on PACG outcome. Besides, the area under the receiver operating characteristic curve was 0.55 and non-significant (P = 0.42).
Conclusion: There is no association between plasma levels of 8-OHdG and PACG or its specific clinical markers. Further studies in a much larger cohort are needed to validate these findings.
Keywords: 8-OHdG, DNA damage, glaucoma, oxidative stress, Saudi Arabia