Using fruit flies to better understand risks associated with blue light

Here at the Oregon Institute of Occupational Health Sciences we are fortunate to have a group of scientists who research at the basic science level together with researchers working as applied scientists. Our basic scientists are working to understand factors at the genetic, epigenetic, cellular and organism level that ultimately help us better understand impacts to humans from a whole host of detrimental agents and exposures.

One of our basic research faculty members is Dr. Doris Kretzschmar. Dr. Kretzschmar is an Associate Professor here at the Institute as well as within OHSU’s School of Medicine Molecular and Medical Genetics Program. She holds several other affiliations within the School of Medicine. Within the Kretzschmar Lab, the team uses Drosophila (better known as fruit flies) to study basic mechanisms of neurodegeneration.

Dr. Doris Kretzschmar

Dr. Kretzschmar, along with Dr. Giebultowicz at Oregon State University, recently published the article, “Daily blue-light exposure shortens lifespan and causes brain neurodegeneration in Drosophila.” Findings from this research, and the topic, is of high interest to many of us as we better educate ourselves on the effects of blue light on humans, including its impact on our circadian rhythms.

While light is necessary for life, scientists help us understand how prolonged exposure to artificial light is of increasing health concern. As we are exposed to increased amounts of light in the blue spectrum, we continue to learn how increased amounts of light in the blue spectrum (often produced by light-emitting diodes, or LEDs) can interfere with normal sleep cycles. Because LED technologies are relatively new, the long-term effects of exposure to blue light across the lifespan are not understood. Dr. Kretzschmar’s research team investigated the effects of light in fruit flies (Drosophila melanogaster), and learned that flies kept in daily cycles of 12-hour blue LED and 12-hour darkness had significantly shorter lives as compared to flies living in either constant darkness, or white light with blue wavelengths blocked. Additionally, the adult flies exposed to daily 12-hour blue light showed accelerated damage to retinal cells, brain neurodegeneration, and impaired movement. Also, the research demonstrated that blue light causes expression of stress-responsive genes in old flies but not in young, suggesting that cumulative light exposure acts as a stressor during aging. This study reveals the unexpected effects of blue light on fly brain and establishes Drosophila as a model in which to investigate long-term effects of blue light at the cellular and organismal level.

We applaud Dr. Kretzschmar and her colleagues for their additions to the literature as we continue to work to understand the impact of blue light on humans.

Additional Resources:
Blue Light has a Dark Side from Harvard Health Letter
Blue Light: What is it and How Does it Affect Us? from Occupational Health and Safety Online