Disruption of circadian rhythms may contribute to inflammatory disease

http://www.eurekalert.org/pub_releases/2014-05/rumc-doc052114.php

PUBLIC RELEASE DATE: 21-May-2014
Contact: Nancy DiFiore
Rush University Medical Center
Disruption of circadian rhythms may contribute to inflammatory disease

New study suggests chronic disruption negatively affects intestinal flora

A disruption of circadian rhythms, when combined with a high-fat, high-sugar diet, may contribute to inflammatory bowel disease and other harmful conditions, according to a recent study conducted by researchers at Rush University Medical Center. The study is online at the peer-reviewed, open-access journal, PLOS ONE.

"Circadian rhythms, which impose a 24-hour cycle on our bodies, are different from sleep patterns," said Robin M. Voigt, PhD, assistant professor at Rush Medical College and first author of the study. "Sleep is a consequence of circadian rhythms," Voigt said.

While circadian rhythm disruption may be common among some, the research suggests that it may be contributing to a host of diseases that may be prevented by regulating things such as sleep/wake patterns and times of eating to help prevent circadian rhythm disruption. Including prebiotics or probiotics in the diet can also help normalize the effects of circadian rhythm disruption on the intestinal microbiota to reduce the presence of inflammation.

"It's something that needs to be addressed — not something people need to be very concerned about, but aware. If you have some of these other risk factors, like a high-fat, high-sugar diet," or a genetic tendency toward disruption in circadian rhythms, "take precautions, watch your diet, take pre- and probiotics, monitor your health, be vigilant," Voigt said.

The prevailing theory is that of a "second hit hypothesis" whereby individuals with at-risk lifestyle choices or genetic predispositions will only develop disease if a secondary insult is present. "We believe that chronic circadian rhythm disruption promotes/exacerbates inflammatory-mediated diseases, at least in part, due to changes in the intestinal microbiota," she said.

Inflammation is associated with a number of diseases, including cardiovascular disease and cancer, and can cause organ damage and is associated with increased morbidity and mortality.

-----

These findings support previous studies that have shown that the negative effects of circadian disruption are subtle enough that "a second environmental insult is often necessary to reveal [their] deleterious effects," the study says.

Many people have their circadian rhythms disrupted on a regular basis — shift workers like nurses, doctors, firefighters and policemen. "Other people have 'social jet lag,' a lifestyle pattern that leads them to maintain a normal schedule on weekdays, but then stay up late and sleep in on the weekends," Voigt said.

"Looking forward, we would like to functionally evaluate how circadian rhythm disruption may influence diseases including colon cancer, which may in part be the consequence of altered intestinal microbiota," she concluded.