Almost one third of human life passes on sleeping. A good night sleep helps us function well and welcome the new day. Scientists identified a signaling pathway within brain cells that regulate how long and how deeply we sleep. A good night’s sleep can work wonders for mind and the body. A question arises how much we need to sleep and what can cause us to sleep more deeply. In a new study researchers from University of Tsukuba in Japan have now provided some answers revealing a singling pathway within brain cells that regulate the length and depth of sleep.
The researchers examined mutations in mice and how these affect their pattern of sleep. The mutation was identified that led to the mice sleeping much longer and more deeply than usual. This was caused by low levels of an enzyme called histone deacetylase which is known to suppress the expression of target gene. The previous study have shown that it is greatly affected by attachment of phosphate molecule in a process known as phosphorylation. .” The team found that when there was a lack of SIK3 or when HDAC4 was modified to prevent phosphorylation, the mice slept less. In contrast, when the mice had a more active version of SIK3, which increased the phosphorylation of HDAC4, they slept a lot more.
The team carried out further experiments top identify the brain cells in which these pathways regulate sleep. This involved altering the amount of SIK3 and HDAC4 in different cell types and brain regions. The results indicated that signaling within the cells of the cortex regulates the depth of sleep, while signaling within the hypothalamus regulates the amount of deep sleep. For both brain regions, the excitatory neurons, which can activate other neurons, were identified as playing a key role.
These results provided an important insight into how sleep s regulated and which could potentially led to greater understanding of sleep disorders as well as development of new treatments.