Toxic Effect of Visible Light on Drosophila Life Span Depending on Diet Protein Content.

We investigated the toxic effect of visible light on Drosophila life span in both sexes. The toxic effect of ultraviolet light on organisms is well known. However, the effects of illumination with visible light remain unclear. Here, we found that visible light could be toxic to Drosophila survival, depending on the protein content in diet. In addition, further analysis revealed significant interaction between light and sex and showed that strong light shortened life span by causing opposite direction changes in mortality rate parameters in females versus males. Our findings suggest that photoaging may be a general phenomenon and support the theory of sexual antagonistic pleiotropy in aging intervention. The results caution that exposure to visible light could be hazardous to life span and suggest that identification of the underlying mechanism would allow better understanding of aging intervention.