Sleep is so important to the body in many ways. If you've found yourself feeling sleep deprived, it's important to remedy this issue for your immune system's sake!
By Carolyn Hendler via TVR.org:
"New research published in the Journal of Experimental Medicine shows that lack of sleep has a negative effect on the immune system and can cause long standing inflammation and contribute to inflammatory disease. The structure of DNA residing in immune stem cells, which produce white blood cells, is altered with insufficient sleep. When these immune cells increase in number instead of fighting infection as they are supposed to do, they can overreact and cause inflammation.
While the connection between sleep and the immune system has been known a long time, this study was the first to show that hematopoiesis, a process where certain white blood cells called monocytes form, develop, and are primed to support immune function, is influenced by lack of sleep.
This study begins to identify the biological mechanisms that link sleep and immunological health over the long-term. It shows that in humans and mice, disrupted sleep has a profound influence on the programming of immune cells and rate of their production, causing them to lose their protective effects and actually make infections worse—and these changes are long-lasting.
Sleep Deprivation Genetically Alters Stem Cells, Causes Inflammation
The study looked at blood samples, paying particular attention to immune cells, from 14 healthy volunteers who enjoyed eight hours of sleep a night for six weeks and compared it to blood samples taken from the same volunteers after being limited to only six and a half hours sleep for six weeks. Researchers looked at morning and afternoon blood samples during the fifth and sixth week of the study. The afternoon blood samples of the sleep deprived group showed an increase in circulating monocytes in the afternoon and evidence of immune activation with a higher number of immune stem cells in the blood.
The changes that took place in the blood when the volunteers had a less sleep showed significant long-term changes in the activity of stem cells causing increased white blood cells and inflammation.
Senior study author Filip Swirski, PhD said:
The stem cells have been imprinted, or genetically altered, under the influence of sleep restriction. The change isn’t permanent, but they continue to self-replicate at a higher rate for weeks.7
Sleep deprivation caused a change in the stem cells whereby the process in which genetic material is turned on and off, otherwise known as epigenetics, appeared to be permanently altered. If the lack of sleep continues, the marks on the stem cells could continue to proliferate and lead to less diversity among immune cells, which may result in a poorer functioning immune system.
Study on Sleep Deprived Mice Found Permanent Damage to Immune System
A similar experiment was also conducted on mice. The mice were divided into two groups One group had uninterrupted sleep while the other only had fragmented sleep for 16 weeks. The mice who only had fragmented sleep were then given 10 weeks of uninterrupted sleep to recover. Immune stem cells and immune cells were studied from all of the mice in the different groups, uninterrupted sleep, fragmented sleep and recovery, with the results being consistent with the human studies.
The sleep deprived mice not only had an increase number of immune cells, there was evidence of rewiring and reprogramming of the immune system that did not return to normal after the mice were allowed to regain uninterrupted sleep, which left the mice more susceptible to disease and increased inflammation.
Our findings suggest that sleep recovery is not able to fully reverse the effects of poor-quality sleep. We can detect a molecular imprint of insufficient sleep in immune stem cells, even after weeks of recovery sleep.
Quality Sleep Protective Against Heart Disease, Cancer and Dementia
Cameron McAlpine, PhD, co-lead investigator of the study, pointed out that lack of sleep causes an increase in inflammation which, in turn, can cause a host of health-related issues including cardiovascular disease.
Dr. McAlpine warned:
It was surprising to find that not all clusters of stem cells responded to insufficient sleep in the same way. There were some stem cell clusters that proliferated and grew in number, while other clusters became smaller. This reduction in overall diversity and aging of the immune stem cell population is an important contributor to inflammatory diseases and cardiovascular disease.
Marishka Brown, PhD, director of the National Center on Sleep Disorders Research, summarized:
Sleep impacts optimal functioning of nearly every cell and organ in the body. The mechanistic insight from this study supports findings from larger population studies, which have shown that sleep can have a protective effect against a variety of conditions, including heart disease, cancer, and dementia."