Written by Loren Grush
Researchers have discovered a chemical that could be used to develop completely new drugs to treat metabolic disorders like type 2 diabetes – a condition affecting 25 million people in the United States.
However, the newly isolated chemical is not directly involved in the regulation of glucose production in the liver. Instead, it is involved in the management of our circadian rhythm – more commonly known as the biological clock.
The research, published Friday in the online issue of the journal Science, detailed how the discovery came as a surprise to the biologists of UC San Diego when they were searching for a molecule that could lengthen the biological clock.
The team, led by Steve Kay, dean of the division of biological sciences at UC San Diego, was analyzing human cell cultures in individual wells in which a gene from fireflies is attached to the biological clock machinery, allowing the cells to glow whenever the biological clock had been activated. After screening the compounds with an extensive chemical library, they were able to isolate this chemical – which they have currently dubbed “KL001.”
“After doing a lot of work in lab, the chemical we identified was hitting a target – a protein called cryptochrome,” Kay added. “It’s a protein that is found in most organisms and it’s been identified as having a very important role in biological rhythm, almost like a molecular cog of the biological clock.”
But from previous research, Kay and his team knew that cryptochrome was also used in another, seemingly unrelated process in the human body.
“A few years earlier, my lab had begun to associate the activity with cryptochrome was involved in metabolic regulation,” Kay said. “On a daily basis, it makes sure the liver’s activity is a match with our own activity. So it suppresses glucose production during the day, when we’re eating and don’t need much glucose. But at night, when we’re fasting and glucose is low, it increases our levels.”
According to the National Institutes of Health, the biological clock exists in most cells throughout the body, helping to regulate our sleep/wake cycle.