Disruption of central and peripheral circadian clocks and circadian controlled estrogen receptor rhythms in night shift nurses in working environments.

🎖️ Top 10% JournalJun 5, 2024FASEB journal : official publication of the Federation of American Societies for Experimental Biology

Disrupted body and brain daily clocks and estrogen rhythms in night shift nurses at work

AI simplified

PubMed ↗DOI ↗OA ↗

Abstract

Chronic night shift work is associated with disrupted circadian rhythms, particularly in cortisol and circadian gene expressions.

Day shift nurses exhibited aligned 24-hour rhythms of cortisol and melatonin with peak values in the morning.
Night shift nurses lost the normal 24-hour rhythmicity of cortisol, resulting in a suppressed morning surge.
Melatonin rhythms remained normal in night shift nurses, leading to a misalignment between cortisol and melatonin.
Disruption of rhythmic expressions of peripheral circadian genes (PER2, PER3, BMAL1, and ESR2) was observed in night shift nurses.
An impaired correlation between PER2 and BMAL1 was found in night shift nurses compared to their day shift counterparts.
Morning plasma cortisol and expressions of PER2, BMAL1, and ESR2 may serve as potential biomarkers for circadian disruption in shift workers.

AI simplified

Chronic disruption of circadian rhythms by night shift work is associated with an increased breast cancer risk. However, little is known about the impact of night shift on peripheral circadian genes (CGs) and circadian-controlled genes (CCGs) associated with breast cancer. Hence, we assessed central clock markers (melatonin and cortisol) in plasma, and peripheral CGs (PER1, PER2, PER3, and BMAL1) and CCGs (ESR1 and ESR2) in peripheral blood mononuclear cells (PBMCs). In day shift nurses (n = 12), 24-h rhythms of cortisol and melatonin were aligned with day shift-oriented light/dark schedules. The mRNA expression of PER2, PER3, BMAL1, and ESR2 showed 24-h rhythms with peak values in the morning. In contrast, night shift nurses (n = 10) lost 24-h rhythmicity of cortisol with a suppressed morning surge but retained normal rhythmic patterns of melatonin, leading to misalignment between cortisol and melatonin. Moreover, night shift nurses showed disruption of rhythmic expressions of PER2, PER3, BMAL1, and ESR2 genes, resulting in an impaired inverse correlation between PER2 and BMAL1 compared to day shift nurses. The observed trends of disrupted circadian markers were recapitulated in additional day (n = 20) and night (n = 19) shift nurses by measurement at early night and midnight time points. Taken together, this study demonstrated the misalignment of cortisol and melatonin, associated disruption of PER2 and ESR2 circadian expressions, and internal misalignment in peripheral circadian network in night shift nurses. Morning plasma cortisol and PER2, BMAL1, and ESR2 expressions in PBMCs may therefore be useful biomarkers of circadian disruption in shift workers.

Full Text

Full text is available at the source.

View full text ↗

Abstract

Full Text

Related papers