An ultraviolet radiation-based micronucleus assay for measurement of DNA damage and its application to nutrition research.

摘要

The aims of this study were to develop an ultraviolet (UV) radiation-based micronucleus assay for measurement of oxidative DNA damage levels and to examine its applicability to nutrition research. WIL2-NS cells were exposed to UV radiation, and the frequency of micronucleated cells was determined as an indicator of oxidative DNA damage. UVA radiation at 420 micro W/cm2 did not significantly increase the number of micronucleated cells, whereas UVB radiation at 300 micro W/cm2 for 0-5 s induced an increase in the count of micronucleated cells that was proportional to the period of exposure. Similar results were obtained when WIL2-NS cells were substituted with human lymphocytes, indicating that UVB radiation can be applied to the micronucleus assay. Furthermore, analysis of blood samples collected from female high school students demonstrated a significant negative correlation between the blood beta -carotene level and frequency of UV-induced micronucleus formation (r=-0.443, p<0.05). These observations suggest that UVB-enhanced oxidative damage can be used for evaluating the antioxidant properties of certain nutrients such as beta -carotene.