SYDNEY: Breakthrough X-ray research mapping how insulin works at a molecular level could lead to new diabetes treatments and end daily needle jabs for hundreds of millions of sufferers, scientists said yesterday.
A US-Australian team said it had revealed in atomic detail for the first time how the hormone insulin binds to the surface of cells, triggering the passage of glucose from the bloodstream so that it is stored as energy.
Scientists have been trying to work out how this binding mechanism works for more than 20 years and the discovery should unlock new and more effective drugs to treat diabetes, lead researcher Mike Lawrence said.
“Until now, we have not been able to see how these molecules interact with cells,” said Lawrence, from the Walter and Eliza Hall Institute of Medical Research in Melbourne.
“We can now exploit this knowledge to design new insulin medications with improved properties, which is very exciting.”
Lawrence said the team’s study, published in the journal Nature, had revealed a “molecular handshake” between the insulin and its receptor, or docking point, located on the surface of cells.
“Both insulin and its receptor undergo rearrangement as they interact — a piece of insulin folds out and key pieces within the receptor move to engage the insulin hormone,” he said of the “unusual” binding method.
Understanding how this docking works opens the way to novel treatments of diabetes, a chronic condition in which the pancreas does not produce enough insulin or the body cannot use the hormone properly. “The generation of new types of insulin have been limited by our inability to see how insulin docks into its receptor in the body,” Lawrence said.
“This discovery could conceivably lead to new types of insulin that could be given in ways other than injection, or an insulin that has improved properties or longer activity so that it doesn’t need to be taken as often.”
The discovery could also help treatment of diabetes in developing nations, enabling more stable man-made insulins that do not need refrigeration.
It could also have applications in the treatment of cancer and Alzheimer’s, with insulin playing a role in both diseases, he added.
“Our finding is a fundamental piece of science that ultimately might play across all three of those very serious diseases,” Lawrence said.
There are an estimated 347 million diabetes patients worldwide and numbers are increasing, particularly in developing countries where obesity and sedentary lifestyles are growing.
It is expected to be the seventh leading cause of death in the world by 2030, with the World Health Organisation projecting total deaths from diabetes will rise by more than 50 percent in the next 10 years. Complications of diabetes include heart disease, blindness, limb amputation and kidney failure.
The Australian Diabetes Council, a lobby group representing people with the condition, said the development was welcome news. “While we do not currently have a cure for diabetes, discoveries such as this insulin docking breakthrough give us hope that it is coming ever closer,” said council chief Nicola Stokes.
Diabetes is a complex disease and new treatments usually take many years of design and testing before they emerge on the market, and this area of research has known many disappointments.
AFP
