According to the latest scientific research, sleep can provoke a series of genetic changes that enhance the production of a specific type of brain cell, responsible for sustaining critical neurological function. In stark contrast, if you’re not getting those 40 winks then the numbers of this particular cell may be face a hammering.
It’s in the Genes
The brain cell in question is called an oligodendrocyte. These cells serve a support role, organizing the production of myelin sheath in the central nervous system. Myelin sheath is a lipid-protein structure, which lines the nerves at intermittent points, and is critical to the efficient conduction of electrical transmissions.
According to the latest research efforts, published in The Journal of Neuroscience, sleep can “switch on” the genes implicated in sustaining the assembly of myelin. The study was performed by Chiara Cirelli, of the University of Wisconsin, and her colleagues. The team sought to investigate the difference in gene activity between two groups of mouse models; one set of mice were granted sleep, whereas an entirely different set experienced prolonged sleep deprivation.
The results were fairly startling. As discussed, in mice who were granted a regular sleeping regime, a selection of genes responsible for myelin sheath formation were switched on. However, in those mice who had been forced to remain awake a completely different set of genes became activated, involved in inducing cellular stress mechanisms and cellular death.
Oligodendrocyte Precursor Cells
Aside from these genetic alterations, the research group established a difference in the production of another cell type, called oligodendrocyte precursor cells (OPCs), which eventually mature to become the myelin-manufacturing oligodendrocyte cells.
Without this myelin sheath, normal cognitive function can become seriously impaired. This is witnessed in multiple sclerosis (MS), for example, a degenerative neurological condition characterized by the immune-mediated destruction of this protective layer; likewise, trauma can also cause damage to these myelin layers. Symptoms range in severity and form, depending upon the affected region; however, sensory and visual problems are frequently encountered, alongside balance and mood disorders.
In the picture to the right, you can see clear differences in the structural integrity of the myelin sheathing between healthy and damaged nerves. In a healthy nerve the electrical impulses are propagated between the units of this sheathing, essentially allowing the impulse to “jump” from point to point. When damaged these “jumps” cannot occur and electrical transmission is far slower.
Other Consequences of Sleep Deprivation
The global consequences of sleep deprivation have been extensively studied in the past. A 2010 study, called effects of sleep deprivation on cognition, indicates that inadequate sleep can result in decreased every-day performance, reduced cognitive capacity and may even trigger emotional changes.
Meanwhile, a 2006 study, called changes in brain gene expression after long-term sleep deprivation, sought to understand some of the genetic alterations that occur in sleep-deprived rodents. The authors found that sleep deprivation provoked unfavorable inflammatory and stress responses in the cerebral cortex within the brains of tested animals.
Aside from this, an array of scientific studies have suggested a link between poor sleeping patterns and a host of common health conditions, including:
- Impaired digestion
- Reduction in growth hormones
- Depression and altered sex-drive
- Poor attention span and working memory
- Elevated blood pressure
A very recent study, performed by research scientists from the University College London and the University of Surrey, hypothesized that sleep is necessary for crucial “repair and maintenance” of neuronal brain cells.
A Sleep and Chronobiology lecturer, operating from the University of Surrey, offered his opinion on the team’s findings:
“The London Underground for example, can only function properly during the day because it has extensive maintenance every night. We suggest that sleep allows a similar period of maintenance for the brain.”
Cirelli’s study reveals a potential means by which sleep deprivation could present a danger to the number of OPCs present within the central nervous system, which has a knock-on impact on the production of myelin around neuronal cells.
Aside from demonstrating a hammering in the number of oligodendrocyte brain cell numbers, the results of the study also offer another potential avenue of research. According to Cirelli, sleep deprivation’s detrimental influence on myelin formation could exacerbate some of the symptoms seen in MS patients. On this basis, she suggests further research into this aspect of sleep deprivation should be considered.
By: James Fenner