Just a few days of night work can disrupt the body’s rhythms that regulate blood sugar, energy metabolism and inflammation.
- American researchers have identified proteins that are associated with the effects of circadian shift.
- Insulin regulatory pathways and inflammation-related proteins showed markedly different temporal patterns after just three days of night shift work.
- The struggle between the central clock mechanisms controlling insulin secretion and the peripheral clock mechanisms regulating insulin sensitivity can lead to adverse long-term consequences, such as diabetes and obesity.
“There are processes linked to the master biological clock in our brain that say day is day and night is night, and other processes that follow rhythms set elsewhere in the body that say night is day is night When internal rhythms are disrupted, the system experiences lasting stress which we believe has long-term health consequences. has explained Hans Van Dongenprofessor at Washington State University Elson S. Floyd School of Medicine.
Night work: protein rhythms changed ‘substantially’
In a recent study, the researcher and his team analyzed the effects of circadian shift by establishing the protein profile of peripheral blood mononuclear cells taken from healthy people. In detail, they subjected adults to simulated night or day work schedules for three days in a controlled laboratory experiment. After their last service, participants were kept awake for 24 hours under constant conditions (lighting, temperature, posture and diet) in order to measure their internal biological rhythms without external disturbance. During this period, blood samples were taken at regular intervals and examined to identify proteins present in cells of the immune system.
The results, published in the journal Journal of Proteome Research, showed that certain proteins exhibit rhythms closely linked to the master biological clock, which keeps the body on a 24-hour rhythm. The master body clock is resistant to schedule changes so the rhythms of these proteins do not change much in response to night work. However, most other proteins had rhythms that changed from “substantial manner” among volunteers working at night compared to those working during the day.
A reversal of glucose rhythms in night workers
By taking a closer look at the proteins involved in glucose regulation, the authors observed a reversal of glucose rhythms in people working night shifts. They also found that the processes involved in insulin production and sensitivity, which normally work together to maintain healthy glucose levels, were no longer synchronized in participants working night shifts. According to the scientists, this effect could be due to the regulation of insulin which attempts to undo the changes in glucose triggered by night work. “This may be a healthy response in the immediate term, as altered glucose levels can damage cells and organs, but it could be problematic in the long term.”
“So we can actually see a difference in the molecular patterns between volunteers with normal schedules and those whose schedules are misaligned with their biological clock. The effects of this mismatch had not previously been characterized at this molecular level and in such a controlled manner”, said Jason McDermott, co-author of the study. In their conclusions, the team recalled that protein rhythms linked to blood sugar regulation, energy metabolism and inflammation are processes that can influence the development of chronic metabolic diseases, such as obesity and diabetes. . So, it is important that they are not disturbed.
