Night shift schedule causes circadian dysregulation of DNA repair genes and elevated DNA damage in humans
Bala S.C. Koritala Kenneth I. Porter Osama A. Arshad Rajendra P. Gajula Hugh D. Mitchell Tarana Arman Mugimane G. Manjanatha Justin Teeguarden Hans P.A. Van Dongen
Commentaries by Robert Gorter, MD, PhD.
doi:10.1111/jpi.1272627 February 2021
Circadian disruption has been identified as a risk factor for health disorders such as obesity, cardiovascular disease, and cancer. Although epidemiological studies suggest an increased risk of various cancers associated with circadian misalignment due to night shift work, the underlying mechanisms have yet to be elucidated. We sought to investigate the potential mechanistic role that circadian disruption of cancer hallmark pathway genes may play in the increased cancer risk in shift workers. In a controlled laboratory study, we investigated the circadian transcriptome of cancer hallmark pathway genes and associated biological pathways in circulating leukocytes obtained from healthy young adults during a 24‐hour constant routine protocol following three days of simulated day shift or night shift. The simulated night shift schedule significantly altered the normal circadian rhythmicity of genes involved in cancer hallmark pathways. A DNA repair pathway showed significant enrichment of rhythmic genes following the simulated day shift schedule, but not following the simulated night shift schedule. In functional assessments, we demonstrated that there was an increased sensitivity to both endogenous and exogenous sources of DNA damage after exposure to simulated night shift. Our results suggest that circadian dysregulation of DNA repair may increase DNA damage and potentiate elevated cancer risk in night shift workers.
Source: Washington State University / Contact: Hans Van Dongen – Washington State University
My team and I have looked at DNA repair mechanisms and what disrupts DNA repair since the early 1990’s.
Firstly, we could document that practically all cancer patients, who requested to be treated according to the Gorter Model, had a significantly disrupted Circadian Rhythm and a significant lower core body temperature compared to healthy (and nonsmoking) individuals.