No-needle insulin treatment beckons

Breakthrough research into how insulin works at the molecular level could lead to new diabetes treatments and end daily injections for hundreds of millions of sufferers.

A US-Australia team of scientists yesterday said it has been able to detail for the first time how the insulin hormone binds to the surface of the body's cells, allowing the passage of glucose into the cells from the bloodstream. The glucose is used as fuel by cells.

Lead researcher Mike Lawrence said the discovery, more than 20 years in the making and made possible by the use of powerful X-ray beams, would lead to the development of new and more effective diabetes medications.

"Until now we have not been able to see how insulin molecules interact with cells," said Lawrence, of the Walter and Eliza Hall Institute for Medical Research, Melbourne.

"We can now exploit this knowledge to design new insulin medications with improved properties."

Lawrence said the team's study, published in the latest edition of Nature, had revealed an unusual "molecular handshake" between insulin and its receptors 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.

Understanding how insulin attaches to cells is crucial in developing new treatments for diabetes, a chronic condition in which the pancreas does not produce enough insulin or the body cannot use it efficiently.

"The generation of new types of insulin has been limited by our inability to see how insulin docks into its receptors [on cells]," Lawrence said.

"This discovery could conceivably lead to new types of insulin that can be given in ways other than injection, or an insulin that has improved properties or longer activity so that it doesn't have to be taken as often."

Lawrence said the discovery could also have ramifications for the treatment of diabetes in developing nations, allowing for the creation of more stable insulins that do not need to be stored under refrigeration.

It might also have applications in the treatment of cancer and Alzheimer's, with insulin playing a role in both diseases.

"Our finding is fundamental science that ultimately might play across all three of these very serious diseases," Lawrence said.

The Australian Diabetes Council, a lobby group representing people with the condition, said the development was welcome news.

"Though we do not currently have a cure for diabetes, discoveries such as this insulin-docking breakthrough give us hope that one is getting closer," said council chief Nicola Stokes.

Stokes said one Australian was diagnosed with diabetes every five minutes and its prevalence was growing by 8% a year, making it the country's fastest-growing chronic disease and biggest health issue.

There are an estimated 347million diabetes sufferers worldwide and diagnoses are increasing, particularly in developing countries, because of increasing obesity and physical inactivity. Complications of diabetes include heart disease, blindness, gangrene and kidney failure.