Biological clock a 'tangible' internal clock in brain, reveals study

 The circadian clock, also known as the biological or body clock, has been identified as a visible internal clock after scientists discovered the signaling mechanism in brain neurons, according to a new study published in the academic journal Science on Friday.

Almost all mammals` physiological functions are ruled by the internal circadian rhythm to adapt to the rotation of day and night, and the coordination of physiology with daily rhythms is regulated by the neuron of the suprachiasmatic nucleus (SCN), the central pacemaker of the biological clock, said scientists from China's People's Liberation Army (PLA) Academy of Military Sciences. In contrast to the traditional concept of an invisible biological clock, the scientists found a "tangible hand" of a biological clock in SCN neurons, which is called primary cilia. Each neuron contains one primary cilium on the cell membrane, and the antenna-like cilium stretches every 24 hours, mediating Sonic Hedgehog (SHH) signaling that "allows cells in the master circadian clock to maintain synchronization and control circadian rhythmicity," said the study titled "Rhythmic cilia changes support SCN neuron coherence in circadian clock." "The biological clock was previously thought to be an invisible clock, while this time we found that the antennae-like primary cilia sticking out of the cell surface show rhythmic changes, indicating that the biological clock is a tangible and visual internal clock," said Li Huiyan, researcher at the PLA Academy of Military Sciences and author of the study. The researchers used mice for the experiment. After exposure to the modified light cycle to induce the experimental jet lag, the cilia-deficient mice adapted to the new time cycle in one to two days, while the normal mice take seven to nine days. "Disruption of SHH signaling allows

"Disruption of SHH signaling allows animals to adapt more quickly to changing environments," the study said. Li said the mechanism could be used to regulate the circadian clock. "When our rhythm becomes disordered, we can 'turn it off', and when the external environment gives us a new rhythm, our bodies can quickly establish a rhythm. new stable, sane, completely in tune with the outside world," Li said. . . A stable circadian clock is essential for good health and irregular rhythms can lead to bad consequences such as sleep disturbances, metabolic disorders, impaired immunity and serious diseases such as cancer. tumors, diabetes and mental disorders. The discovery "opens a new avenue for the research and development of rhythm-regulating drugs, allowing our bodies to rapidly respond to environmental disturbances and adapt to complex environments." , Li said.