A team of University researchers, in collaboration with British scientists, recently unearthed a new finding about the human biological clock that could have serious repercussions for how people combat jet lag, insomnia and other circadian rhythm disorders.

The biological clock is responsible for regulating circadian rhythms, or “24-hour oscillations of all kinds of biological processes,” said Casey Diekman, a graduate student at the University and collaborator on the study.

“These rhythms are present in all kinds of organisms, plants, animals and of course humans. The most obvious one is the sleep/wake cycle and this rhythm is controlled by a clock within the body.”

The human biological clock is located in a region in the central brain — called the suprachiasmatic nuclei, or SCN — and up until now researchers had thought the rate at which SCN cells emit electrical pulses is what controls the time-keeping mechanism in the body.

But the team of researchers found that that model is, quite simply, wrong.

The University research team was led by Daniel Forger, associate professor of mathematics and research assistant professor of the University’s Center for Computational Medicine and Bioinformatics.

Together, Forger and Diekman used mathematical models to discover properties of the signals sent from the brain to the body to regulate time and circadian rhythms.

“We took a lot of the data about what the signal was, and parts of the signal and tried to put it all together to find what the daily code for timekeeping was,” Forger said. “(Our findings) were not only counterintuitive but hardly believable.”

According to Forger, the previously accepted model for circadian rhythms held that neurons communicated with each other by sending short electrical pulses from the SNC and that these pulses were sent at a higher rate during the day and a slower rate at night.

After studying the neurons, however, Forger and Diekman found something different.

“We found that these pulses were only being sent out at dawn and at dusk,” Forger said. “At the middle of the day the cell would go to this very excited state so that it wouldn’t give off the impulses.”

Forger and Diekman, however, soon came across an opportunity for collaboration that would lead to a better understanding of their discoveries about the biological clock.

After attending a conference for the Society for Research on Biological Rhythms in May 2008, Diekman attended a post-conference party where he met Dr. Hugh Piggins, a British scientist also studying biological clock processes.

When Diekman discussed his findings with the British scientist, Piggins said he had a way to test these theories and an international research collaboration was born.

According to Forger, Piggins claimed he “could identify the cells in this region that did have a clock in them and that those cells did seem to behave very differently.”

“Almost immediately I decided one of us had to go to England to visit these guys,” Forger said. “I handed the keys of my (Toyota) Prius to Casey to take across the Canadian border to Toronto to get a flight and go to Manchester, England, and thus began the collaboration.”

Diekman said that the research revealed some of the most important mechanisms of the internal clock.

“Now we know that during the day, certain cells that are actually responsible for the clock mechanism are in a silent state, where as previously we thought they were firing really fast,” Diekman said.

“And so this is going to change how people are going to need to design experiments and how people are going to have to think about treating circadian rhythm disorders,” he said.

Piggins’ colleague, Dr. Mino Belle, who was also part of the team, recorded information from 400 cells at all times of the day during the research process.

Belle said the study holds major significance in the study of sleep cycles.

“It gives us an angle to understand how the body clock — the master clock — works,” he said.

Belle also said that with this new information, researchers will be able to better tackle problems associated with sleep disorders in the future.

“The molecules that keep time now give us sort of a window into ways of understanding the clock better,” he said, “and in the future to be able to manipulate these cells in real organisms including ourselves, to combat all the disease-related aspects of the clock.”

Ultimately, their discoveries could lead to vast improvements in the medical world in fighting disorders directly related to the biological clock which includes anything from such as jetlag and obesity to depression and mood disorders.

“I think it’s going to change the way a lot of people think about how the clock sends signals to the rest of the body,” Diekman said.

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