|Molecular markers for assessment of radiationinduced oxidative stress in occupationally exposed subjects|
- Stankova, E. Zaharieva, N. Aneva, O. Katsarska, G. Savova, R. Boteva
The present molecular epidemiological study aims to characterize the individual radiation response, important factor for the individual radiosensitivity. Radiation-induced changes in cellular levels of ROS (reactive oxygen species), mitochondrial membrane potential and antioxidant activity of blood plasma were analyzed, as suitable markers of low-dose gamma radiation exposure. The study included 60 employees of the “Kozloduy” NPP; 40 of them were occupationally exposed to low-dose gamma ionizing radiation and 20 were non-exposed controls from the administrative staff of NPP. The exposed workers were divided into two groups: the first of them included 23 persons with very low cumulative doses, not exceeding 50 mSv and the second group was composed of 17 persons with cumulative doses higher than 50 mSv. Comparison of these groups with the control, non-exposed group showed that the exposed group of workers with cumulative doses exceeding 50 mSv was characterized by the highest dispersion of data on ROS levels. This suggests significant differences in the individual antioxidant defense at cellular level which is most likely due to the fact that the group includes individuals with cumulated doses in a broad range from 52.9 to 257.9 mSv. Analyses of combined effects of dose and age revealed more significant effect of ages than doses on the intracellular levels of radiation-induced oxidative stress, while for the antioxidant activity of blood plasma was found that it is affected by both, age and dose.
|Key words: EPIDEMIOLOGY. OXIDATIVE STRESS. INDIVIDUAL RADIOSENSITIVITY|