Circadian Rhythms and Your Immune System?

It’s an old cliché that life is all about change, but researchers here in Americas’ Yale University of medicine, have discovered just how true it is. They have shown how a protein in the human body, part of its immune system, is susceptible to changes in our body chemistry at different times of the day. Yes, it is a fact that infections will be more or less acute in correlation with phases of the day. The full findings of this notable study are published in ‘Immunity’ the journal.

Body Clocks

The next development will be to synchronize our therapeutic drugs with our body clocks for maximum healing power. Every living organism on Earth goes through a solar cycle known as the circadian rhythm. Think of the effect known as ‘jet lag’ when we fly too fast in the opposite direction to the Earths rotation. This research is investigating the link that has been known for a long time; the link between variation in infection susceptibility and the time of the day.

Circadian Rhythms

Circadian comes from the Latin word ‘circa’ meaning around, and ‘diem’ meaning day because it runs on a 24 hour cycle. Our body functions repeat day after day and it does this in the absence of clues from the immediate environment. There is a short period of adjustment when we travel across time zones but jet lag does not invalidate the fact that we do naturally adapt to the local day-night patterns in which we find ourselves. Interestingly the circadian rhythm is independent of the local temperature. We maintain it even if we fly from an Icelandic winter to an Ecuadorian summer.

Immune System

Before our immune system can fight any infection it first has to detect it. The Yale researchers are looking closely at ‘toll-like receptor nine’ (TLR9) which is a protein that can ‘see’ the genetic make up of bacteria and viruses. Using mice it can be seen that TLR9 is produced in varying amounts according to the circadian rhythm. Timing the immunization of the mice to coincide with maximum TLR9 production times actually improved the effectiveness of their immune response to sepsis otherwise known as blood poisoning.

Circadian Rhythm and Infections

The Yale research has confirmed the direct molecular connection between the daily body rhythm and the immunity to infections. This discovery will have positive ramifications for the immunization and treatment of many infections. Meanwhile it is clear that the interruptions to our body clocks, influences our susceptibility to illness.

Unfortunately it will probably make the timing instructions on packaging even more complex and put the onus for dosing more on the individual. But before that the pharmaceutical companies are all beginning to screen their treatments for effectiveness at various times of the day. The clear aim will be to administer the drug at the correct time so as to ride the maximum wave of immunization.