In vitro approach to the study of chronic exposure to low doses of x-rays

PONZINIBBIO M V; PERAL GARCIA P; SEOANE A I

Basic and Applied Genetics

SOCIEDAD ARGENTINA DE GENÉTICA

Lugar: Buenos Aires; Año: 2011

1666-0390

The present research was undertaken in order to study the effect of repeated low doses of radiation on two different cell lines from the same species. An in vitro model test was developed to avoid the influence of the confounding factors affecting epidemiological studies and to simulate a chronic exposure (50 mSv of x-rays during ten consecutive days). Comet assay and early apoptosis were analyzed immediately after exposure and after chronic irradiation. Sequential irradiation induced an increase of cells showing DNA damage. Index Damage was higher than that of the controls in both cell lines immediately after exposure and after chronic irradiation; these differences between exposed and control cells were statistically significant only for the transformed cell line after chronic irradiation (p<0.001). Significantly higher levels of apoptosis were scored after chronic exposure in both cells lines (p<0.001). The induction of DNA damage and apoptosis in hamster cells by chronic exposure to low dose ionizing radiation was demonstrated. Cell types reacted differently to chronic exposure; though further investigation is needed to understand the mechanisms of radiation effects on chronic low-dose-exposed cell populations, cellular type should be taken into account in the design of in vitro experiments to understand low-dose-irradiation effects.