Study pinpoints how circadian clock controls insulin production in the pancreas

There exist thousands of genetic pathways taken by our internal body clock to dictate when our pancreas should produce insulin and regulate blood sugar, according to new research.
In a previous study, also conducted by researchers at Northwestern University Feinberg School of Medicine, the researchers discovered that each organ has individual “clock” genes, which are controlled by a “master clock” in the brain. When the researchers took the clock genes out of mice, they were unable to regulate blood sugar levels, which led to obesity and type 2 diabetes.
The research is the latest evidence that the body’s circadian rhythms can play a significant role in the development of obesity and type 2 diabetes. Circadian rhythms dictate behaviour like eating, sleeping and metabolism, matching it all up with Earth’s day and night cycle. The effects of circadian rhythms have been identified as an explanation for the higher rates of type 2 diabetes among night-shift workers and people who maintain nocturnal sleep habits.
“We knew that the pancreas didn’t work if we removed these clock genes, but we didn’t know how the genes were affecting the normal function of the pancreas,” said principal investigator Dr. Joe Bass, chief of endocrinology at Northwestern University Feinberg School of Medicine.
The researchers identified thousands of genes located in the pancreas that the pancreas’s clock controls, to keep the body in line with the day and night cycle.
“We established a new gene map that shows how the entire repertoire of factors produced in the pancreas maintain and anticipate daily changes in the external environment,” Bass said. “These factors are all tied to the rotation of the Earth – to the timekeeping mechanism that has evolved to control when we sleep, wake up, eat and store nutrients each day.
“This study reinforces the idea that clocks operating in cells are fundamental to health,” Bass said. “They represent an important untapped target for improving the functions of cells in the pancreas.”
The findings could lead to innovative new treatments for diabetes, as researchers learn more and more about insulin, the pancreas and what makes it function.
The researchers are continuing their investigation into the interaction between the body’s various circadian clocks, and how their rhythm can be thrown off by diabetes, aging, stress and dietary changes.
The findings are published in the journal Nature.