۸-Hydroxy-۲-Deoxyguanosine as Oxidative DNA Damage Biomarker of Medical Ionizing Radiation: A Scoping Review

Background: Recent studies reported the significant expansion using ۸-Hydroxy-۲-Deoxyguanosine (۸-OHdG) as a biomarker of oxidative Deoxyribonucleic Acid (DNA) damage among human populations exposed to medical ionizing radiation, but a generalized overview about this topic has not been conducted yet. Objective: This scoping review of published literature examined recent trends in utilizing ۸-OHdG biomarker to measure oxidative DNA damage induced by medical ionizing radiation and possible factors that may influence the ۸-OHdG level.Material and Methods: Literature search was conducted in PubMed, Scopus and ProQuest databases for publications from ۱۹۸۴ to ۲/۱۲/۲۰۲۰. Included articles were: cohort studies, case-control studies, and cross–sectional studies, randomized and nonrandomized controlled trials. Excluded articles were: editorials, letters, personal opinions, newspaper articles, study plans, protocols, qualitative studies, case reports and series, in-vivo and vitro studies, animal research studies, reviews and meta-analyses. Results: According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we screened ۱۴۱ articles, and ۱۰ eligible studies met our inclusion criteria. All studies measured ۸-OHdG as an oxidative DNA damage biomarker. The study results were contradictory concerning the relationship between the radiation dose and ۸-OhdG level. ۸-OHdG was mostly measured by enzyme-linked immunosorbent assay (ELISA) using urine samples. Sample size varied between (n=۲۵-۲۳۰) and included patients who underwent medical radiation procedures or workers exposed to ionizing radiation during their jobs. Conclusion: This scoping review findings showed ۸-OHdG can be used as a promising biomarker to detect oxidative damage, resulting from medical ionizing radiation exposure despite external factors that may influence ۸-OHdG levels.