The body’s circadian rhythms affect more than just our sleeping patterns. Research has shown there is involvement of the circadian clock genes in some diseases, from arthritis to cancer and others. A recent study has found that these same genes also influence the healing of the body, especially when it comes to post-surgical healing–even down to what time of day you should take anti-inflammatory pain relievers (such as NSAIDs, like ibuprofen) for the most benefit.
Led by McGill University, this study published in Scientific Reports found a correlation between the body’s response to inflammation and the healing process and time of day. The body’s inflammation process is an integral part of the healing process which signals cells to rebuild the damaged tissues. The inflammation process has periods of both reconstruction and healing and destruction of less viable tissues. Taking anti-inflammatory medications are meant to ease the body’s inflammation process, which can be quite severe, and relieve pain to make the patient more comfortable while the body works to heal itself. When we restrict the body’s natural process of inflammation (which is a healing process) by too many anti-inflammatories, are we interfering with the timed processes of the body?
The healing of bones is quite closely tied with circadian rhythms. Bone cells that break down bone tissue are called osteoclasts, and they are only active during the day. At night, specialized bone cells that work to reconstruct bone (called osteoblasts) are active. This is part of the old adage that most of the body’s healing occurs at night. The researchers used this knowledge to design a trial to study bone healing with the addition of anti-inflammatory medications.
They studied the healing of fractured tibia bones in mice which were divided into two groups. They contrasted giving anti-inflammatory medications around the clock versus giving the medications only in the morning. The group of mice dosed only in the mornings was given regular analgesic pain relievers at night (which have no anti-inflammatory properties) to address the mice’s pain control when not offered the anti-inflammatories.
The group of mice which were given anti-inflammatory medication only during the day (the active part of the circadian rhythm) recuperated faster and more completely than the group of mice which were given anti-inflammatories around the clock. The researchers also found that the expression of bone-healing genes was dramatically different between the two groups of mice during the experiment.
The authors of the study point out that working with, and not against, the natural circadian rhythm of the body is a key part of timing medications. They believe that giving anti-inflammatories during the day, instead of at night, will prevent the disruption of the body’s healing that only occurs at night.
This was the first study which demonstrated the effects of circadian rhythms in injuries or surgeries. The same research team is now applying their evidence to a clinical trial regarding wisdom tooth extraction to see if better healing occurs with the same type of medication schedule (anti-inflammatories only during the day and plain analgesics at night).
References
McGill University. “Our biological clock plays crucial role in healing from surgery: Effectiveness of anti-inflammatories following surgery depends on when you take them.” ScienceDaily. ScienceDaily, 22 January 2020. www.sciencedaily.com/releases/2020/01/200122100554.htm.
