Autoimmune diseases may feel worse if our body clock is out of whack

12 Dec 2017

Image: BlurryMe/Shutterstock

A new study into autoimmune diseases suggests that the severity of symptoms might be dependent on how your body clock is ticking along.

A lot of people live with some form of autoimmune disease or another, ranging from multiple sclerosis (MS) to coeliac disease, but new findings suggest that there might be a reason why symptoms appear worse at different times of the day.

In a paper for Nature Communications, a team from Trinity College Dublin (TCD) and the Royal College of Surgeons in Ireland (RCSI) has demonstrated that the body’s immune responses are intrinsically linked with the circadian rhythm of our ‘body clock’.

This natural process has only really been understood to some degree in the last few decades and has been found to help us anticipate and respond to the 24-hour cycle of our planet.

Maintaining a good body clock is generally believed to lead to good health for humans, and disrupting the circadian rhythm has been associated with immune diseases – however, the underlying molecular links have been unclear.

The breakthrough was made during tests with lab mice, which showed that the master circadian gene – BMAL1 – is responsible for sensing and acting on time-of-day cues to suppress inflammation. A loss of BMA1 at midday instead of midnight resulted in more severe autoimmune encephalomyelitis, a type of MS in mice.

Use drugs at different times of day

“In the year that the Nobel Prize in Medicine was awarded for discoveries on the molecular mechanisms controlling the circadian rhythm, our exciting findings suggest that our immune system is programmed to respond better to infection and insults encountered at different times in the 24-hour clock,” explained TCD’s professor of experimental immunology, Kingston Mills.

“This has significant implications for the treatment of immune-mediated diseases, and suggests there may be important differences in time-of-day response to drugs used to treat autoimmune diseases such as MS.”

While further studies are needed to figure out how we can precisely modulate circadian rhythm for beneficial immunity, it could help us figure out how to navigate the rigours of a hectic lifestyle with an autoimmune disease.

RCSI’s Dr Annie Curtis said: “Our study also shows how disruption of our body clocks – which is quite common now, given our 24/7 lifestyle and erratic eating and sleeping patterns – may have an impact on autoimmune conditions.”

Colm Gorey was a senior journalist with Silicon Republic

editorial@siliconrepublic.com