Ionizing radiation, antioxidant response and oxidative damage: A meta-analysis

Area of Science:

• Environmental Health
• Toxicology
• Radiation Biology

Background:

• Oxidative damage is a proposed mechanism linking ionizing radiation exposure to adverse biological effects.
• Chronic low-dose ionizing radiation (LDIR) exposure requires further investigation into its impact on oxidative stress.
• Understanding these effects is crucial for assessing risks in LDIR-contaminated environments.

Purpose of the Study:

• To systematically review and meta-analyze the scientific literature on the effects of LDIR on oxidative damage and antioxidant responses.
• To quantify the overall impact of LDIR on oxidative stress markers.
• To identify factors influencing the variability of these effects across studies.

Main Methods:

• A comprehensive literature survey identified 40 publications with relevant data.
• Meta-analysis of 212 effect sizes for antioxidant responses and 288 for oxidative damage was performed.
• Meta-regression models were used to explore heterogeneity and identify predictive factors.

Main Results:

• Large overall effects were observed for both oxidative damage (unsigned effect size 0.918) and antioxidant response (0.973).
• Ionizing radiation exposure led to small to intermediate increases in oxidative damage (mean signed effect size 0.276) and decreases in antioxidant defenses (-0.350).
• Significant heterogeneity was found, with species, biological matrix, and age influencing the magnitude of effects.

Conclusions:

• The findings support oxidative damage as a key mechanism in the pathological effects of chronic LDIR exposure.
• Results indicate that resistance to oxidative stress may explain variations in species' responses to LDIR.
• This research underscores the importance of considering oxidative stress in radiation protection and environmental risk assessment.