Energy levels link sleep control mechanisms

May 25, 2012 in Medical research

Energy levels link sleep control mechanisms

Credit: Thinkstock

Sleep, or lack of it, can determine level of cognitive performance which is linked with accidents as well as increased risk of serious health problems. Links between cell energy levels, gene transcription and sleep rhythms may uncover answers to sleep disorders and the ill-effects of sleep deprivation.

Timing and quality of sleep is determined by a homeostatic process that compensates for sleeplessness and a to determine the time of day when we should sleep. The effects of even minor misalignments between these two processes, as in jet lag for example, indicate that sleep control is a very relevant feature in and .

Previous studies by the EU-funded 'Redox potential as an interface between sleep homeostasis and circadian rhythms' (Redoxsleepcircadian) project members have suggested that although the two cycles are supposed to operate independently, the two main clock genes work together for homeostatic sleep regulation and generation of . Not only that, but both CLOCK and NPAS2, the core clock genes, depend on the redox potential in cells suggesting that the two sleep mechanisms are linked through .

The aim of the recently completed project Redoxsleepcircadian was to understand the that determine our daytime performance and sleep quality. By inducing circadian rhythms in a type of connective tissue cell, fibroblasts, the sleep scientists could determine if there were any accompanying redox changes.

Using redox genetic probes along with a time lapse imaging system, changes in redox potential were recorded in living fibroblasts. Any increases in transcriptional activity in the clock genes Per1 and Per2 during sleep deprivation may indicate energy deficits in prolonged wakefulness. Per 1 and Per 2 are under direct control of CLOCK and NPAS2.

Results indicated that Per2 regulates activity-induced and circadian mechanisms central to regulation of sleep and wake periods. Moreover, molecular feedback underlying circadian rhythm generation was able to regulate the requirements of homeostatic sleep need.

In parallel, the project team also focused on Per2 in mice. This sleep gene has been observed to increase expression after sleep deprivation (SD) in the rodent. The scientists demonstrated that all living mice increased levels of Per2 protein production with different dynamics in the brain. This was particularly so in the cerebral cortex as well as in the liver and the kidney.

Interestingly, extended times without sleep affected Per2 RNA expression through circadian and non-circadian mechanisms always resulting in increased Per2 protein. This suggests that there is no separation between the two cycles.

At the recent close of the project, Redoxsleepcircadian was further investigating the role of the main circadian pacemaker, the suprachiasmatic nucleus (SCN), a miniscule region on the brain's midline. Regulating many neuronal and hormonal activities, the SCN is key player in the relationship between , sleep and wakefulness.

Ability to control sleep rhythms could mean a welcome reprieve for patients with . Jet lag and disorientation due to shift work for many of the world's labour force could also become things of the past.

Provided by CORDIS search and more info website

not rated yet  

Rank not rated yet
Relevant PhysicsForums posts

More news stories

Study reveals new mechanism for estrogen suppression of liver lipid synthesis

By discovering the new mechanism by which estrogen suppresses lipid synthesis in the liver, UC Irvine endocrinologists have revealed a potential new approach toward treating certain liver diseases.

Medical research created 6 hours ago | popularity not rated yet | comments 0 | with audio podcast

MRI-based measurement helps predict vascular disease in the brain

Aortic arch pulse wave velocity, a measure of arterial stiffness, is a strong independent predictor of disease of the vessels that supply blood to the brain, according to a new study published in the June issue the journal ...

Medical research created 6 hours ago | popularity not rated yet | comments 0

Antibiotics: A new understanding of sulfonamide nervous system side effects

Since the discovery of Prontosil in 1932, sulfonamide antibiotics have been used to combat a wide spectrum of bacterial infections, from acne to chlamydia and pneumonia. However, their side effects can include serious neurological ...

Medical research created 8 hours ago | popularity not rated yet | comments 0 | with audio podcast

Scientists discover molecule triggers sensation of itch

Scientists at the National Institutes of Health report they have discovered in mouse studies that a small molecule released in the spinal cord triggers a process that is later experienced in the brain as ...

Medical research created 8 hours ago | popularity 5 / 5 (2) | comments 0 | with audio podcast

Discarded immune cells induce the relocation of stem cells

Spanish researchers have discovered that the daily clearance of neutrophils from the body stimulates the release of hematopoietic stem cells from the bone marrow into the bloodstream, according to a report published today ...

Medical research created 9 hours ago | popularity 5 / 5 (2) | comments 0


Controlling mood through the motions of mitochondria

(Medical Xpress)—Regulating the distribution of power in neurons is done by a system that makes the national electric grid look simple by comparison. Each neuron has several thousand mitochondria confined ...

Multiple research teams unable to confirm high-profile Alzheimer's study

Teams of highly respected Alzheimer's researchers failed to replicate what appeared to be breakthrough results for the treatment of this brain disease when they were published last year in the journal Science.

Motion quotient: IQ predicted by ability to filter motion (w/ video)

A brief visual task can predict IQ, according to a new study. This surprisingly simple exercise measures the brain's unconscious ability to filter out visual movement. The study shows that individuals whose ...

Researchers find common childhood asthma unconnected to allergens or inflammation

Little is known about why asthma develops, how it constricts the airway or why response to treatments varies between patients. Now, a team of researchers at Weill Cornell Medical College, Columbia University Medical Center ...

Diabetes' genetic underpinnings can vary based on ethnic background, studies say

Ethnic background plays a surprisingly large role in how diabetes develops on a cellular level, according to two new studies led by researchers at the Stanford University School of Medicine.

When oxygen is short, EGFR prevents maturation of cancer-fighting miRNAs

Even while being dragged to its destruction inside a cell, a cancer-promoting growth factor receptor fires away, sending signals that thwart the development of tumor-suppressing microRNAs (miRNAs) before it's dissolved, researchers ...