Despite our broad understanding of the different brain regions activated during rapid-eye-movement sleep, little is known about what this activity serves for. Researchers have now discovered that the activation of neurons in the hypothalamus during REM sleep regulates eating behaviour: suppressing this activity in mice decreases appetite.
While we are asleep, we transition between different phases of sleep each of which may contribute differently to us feeling rested. During (rapid eye movement) REM sleep, a peculiar sleep stage also called paradoxical sleep during which most dreaming occurs, specific brain circuits show very high electrical activity, yet the function of this sleep-specific activity remains unclear.
Among the brain regions that show strong activation during REM sleep are areas that regulate memory functions or emotion, for instance. The lateral hypothalamus, a tiny, evolutionarily well conserved brain structure in all mammals also shows high activity during REM sleep. In the awake animals, neurons from this brain region orchestrate appetite and the consumption of food and they are involved in the regulation of motivated behaviours and addiction.
In a new study, researchers set out to investigate the function of the activity of hypothalamic neurons in mice during REM sleep. They aimed at better understanding how neural activation during REM sleep influences our day-to-day behaviour. They discovered that suppressing the activity of these neurons decreases the amount of food the mice consume. "This suggests that REM sleep is necessary to stabilize food intake", says the senior author. The results of this study have been published in the journal Proceedings of the National Academy of Sciences (PNAS).
The researcher discovered that specific activity patterns of neurons in the lateral hypothalamus that usually signal eating in the awake mouse are also present when the animals were in the stage of REM sleep. To assess the importance of these activity patterns during REM sleep the research group used a technique called optogenetics, with which they used light pulses to precisely shut down the activity of hypothalamic neurons during REM sleep. As a result, the researchers found that the activity patterns for eating were modified and that the animals consumed less food.
"We were surprised how strongly and persistently our intervention affected the neural activity in the lateral hypothalamus and the behaviour of the mice", says the first author of the study and adds: "The modification in the activity patterns was still measurable after four days of regular sleep." These findings suggest that electrical activity in hypothalamic circuits during REM sleep are highly plastic and essential to maintain a stable feeding behaviour in mammals.
These findings point out that sleep quantity alone is not solely required for our well-being, but that sleep quality plays a major role in particular to maintain appropriate eating behaviour. "This is of particular relevance in our society where not only sleep quantity decreases but where sleep quality is dramatically affected by shift work, late night screen exposure or social jet-lag in adolescents", explains the senior author.
The discovered link between the activity of the neurons during REM sleep and eating behaviour may help developing new therapeutical approaches to treat eating disorders. It might also be relevant for motivation and addiction. "However, this relationship might depend on the precise circuitry, the sleep stage and other factors yet to be uncovered", adds the senior author.
https://www.unibe.ch/news/media_news/media_relations_e/media_releases/2020/media_releases_2020/rem_sleep_tunes_eating_behaviour/index_eng.html
https://www.pnas.org/content/early/2020/07/29/1921909117
http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Frem-sleep-stabilizes&filter=22
Stabilizing Feeding Behavior by REM Sleep
- 1,123 views
- Added
Edited
Latest News
Tumor infiltration of immun…
By newseditor
Posted 28 May
New light-controlled 'off s…
By newseditor
Posted 28 May
Gene function during embryo…
By newseditor
Posted 28 May
Formation of 3D blood vesse…
By newseditor
Posted 27 May
Liver regeneration during c…
By newseditor
Posted 27 May
Other Top Stories
Engineering synthetic DNA to study gene regulation
Read more
New stem cell mechanism in your gut
Read more
A stem cell regulator enables lifelong sperm production
Read more
Turning stem cells into sensory interneurons
Read more
Molecular landscapes of human hippocampal immature neurons across l…
Read more
Protocols
SEMORE: SEgmentation and MO…
By newseditor
Posted 26 May
Spatially resolved lipidomi…
By newseditor
Posted 24 May
Efficient expansion and CRI…
By newseditor
Posted 21 May
Massively parallel in vivo…
By newseditor
Posted 20 May
Breast cancer-on-chip for p…
By newseditor
Posted 16 May
Publications
Circadian tumor infiltratio…
By newseditor
Posted 28 May
Kalium channelrhodopsins ef…
By newseditor
Posted 28 May
Double-duty isomerases: a c…
By newseditor
Posted 28 May
Signal switching may enhanc…
By newseditor
Posted 28 May
Emerging paradigms and rece…
By newseditor
Posted 28 May
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar