How Circadian Rhythms Influence Autoimmune Disease
One of the hot research trends in neuroscience involves the mapping and decoding of our circadian rhythms.
Research continues to identify special relationships between specific medical conditions and illnesses and the timing of one's body clock.
Could something as random as the time of day help scientists better understand our rhythms in a way that could help us with treatments and relapse management?
A recent article in the journal Nature Communications shares research from Ireland that seems to suggest this very idea.
Circadian rhythm basics
The 24-hour, light-and-dark cycles of the planet Earth have a strong influence over the sleep-wake cycles of all living things.
Circadian means "about one day, which defines the span of the mutual human processes of wakefulness and sleep.
However, it turns out that, for human beings, sleep is not the only body process that is primarily informed by exposure to light and other time cues associated with the circadian system.
Every single cell in our body has its own circadian clock. While it's true that the main body clock resides in the brain—in a special area known as the suprachiasmatic nucleus, or SCN, buried deeply in the central nervous system—other systems in the body also have their own circadian rhythms that work in tandem with the master clock.
Two main systems with independent circadian drivers include the digestive and immune systems. Both of these systems are subordinate to the master clock, yet have patterns and rhythms of their own.
Listen to your clocks
When it comes to digestion, circadian rhythms determine the time of day when one can digest food. It isn't an accident that the bowel slows down at night as you sleep; this ensures a full night of uninterrupted slumber.
The immune system also seems to impart its own schedule based on time of day. For instance, in the aforementioned Irish study, it was discovered that an activated immune response (such as the inflammation caused by an MS flareup) and its regulation are affected specifically by the time of day.
A master circadian gene known as BMAL1 has been shown to look for and act on time cues during the day to regulate inflammatory responses in laboratory mice. If BMAL1 isn't present, and the mice experienced flareups in the middle of the day, they were shown to have more severe symptoms of relapse than if the same autoimmune attack took place at midnight.
What's also interesting about BMAL1 is that it is a core component of the master clock in the SCN. It yields major influence over the immune system. When the circadian system is disrupted in someone with MS, an increased incidence of disease activity can be traced back to some dysfunction inherent in the BMAL1 gene.
Circadian rhythms, MS & chronotherapy
Researcher Kingston Mills, professor of Experimental Immunology at Trinity College Dublin, recently told Medical Xpress that "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."
Mills said, "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 multiple sclerosis."
What Mills is referencing is a not-so-new concept for treating chronic disease: chronotherapy.
Chronotherapy originally described a treatment approach for cancer patients in 2001 after it was determined that giving chemotherapy at certain times of day yielded better results and fewer side effects.
The problem of circadian disruption
Unfortunately, human beings can suffer from dysfunctional circadian rhythms.
Working night shifts illustrates a classic problem: when people can't stick to a regular bedtime and wake-up time that corresponds with natural rhythms that align with the Earth's light-dark cycles, they end up with chronic and systemic inflammation that can lead to a wide range of health problems, from hypertension and cancer to digestive disorders, mental health issues, and obesity.
This is why the basic practices of sleep hygiene should be part of the daily regimen of anyone diagnosed with chronic disease. It's all about keeping those circadian rhythms in balance.
It's easy to struggle with good circadian synchronicity. People who eat at odd hours or have questionable bedtime habits may be creating more problems for themselves without realizing it.
However, while it can be hard to stick to schedules and patterns when living with a chronic illness and all the other distractions of life, our bodies still require these consistent habits to achieve balance.
Sleep hygiene is a big part of the solution
Good sleep hygiene is one step toward what can be described as a "circadian reset."
Do you practice these habits? They can go a long way to rebalancing your circadian rhythms.
- Eat dinner at least 2 hours before bedtime.
- Eat breakfast in the morning to improve metabolism and give the body necessary energy.
- Get a good dose of sunshine first thing in the morning: just 20 minutes a morning can do wonders for a circadian reset. If you can't receive direct daylight, light therapy works well.
- Skip the alcohol at bedtime, as it fragments your sleep, which is another way to disrupt your circadian rhythms.
- Limit caffeine consumption to the morning hours. Late afternoon coffee or other caffeine products can lead to sleep-onset insomnia.
- Put away handheld electronic devices 1 hour before your planned bedtime. These emit blue spectrum light, which delays the neurochemical processes in the brain that facilitate sleep. If you can't do this, opt to wear blue-blocking eyewear or place blue-light filters on your hardware to ensure your eyes aren't exposed to blue spectrum light.
Don't forget: Sleep is the third pillar of health
So much attention has been placed on eating a "clean" diet and keeping the body moving that any messages about prioritizing sleep might be lost.
However, good health, as described at Harvard's Healthy Sleep website, is composed of not two, but three pillars: nutrition, exercise, and sleep.
Just as a chair can't stand with less than three legs, one's overall health and well-being cannot remain balanced if only two of the three pillars of health are given attention.
If you work hard to eat right and exercise, you are only two-thirds of the way there! Make sleep an equal partner in your daily self-care regimen and you're likely to experience fewer or less severe symptoms when MS does strike.
Have trouble sleeping? Don't write it off as a side effect of MS. Many people with MS have sleep disorders they don't even realize they have.
Sleep disorders are treatable and can do wonders for eliminating daytime fatigue as well as improving your experience living with MS.
Now's the time to make sleep a priority. Have your sleep problems checked out by your primary care physician or MS specialist… you'll wonder later why you waited so long!
Who can relate? "Just because I could do something last year, last month, last week or yesterday doesn’t mean I can do it today. Also, it doesn’t mean I can’t."