Korean and Canadian researchers have cured diabetes in rats and mice in a procedure that holds promise as a treatment for humans.
In a startling piece of research, the team used a genetically engineered virus to deliver a treatment over an eight-month period. The rodents suffered no detectable adverse effects, the researchers report in the journal, Nature. "This new . . . gene therapy may have potential therapeutic value for the cure of autoimmune diabetes in humans," the authors said.
Diabetes is a relatively common disease and affects about 3 per cent of the population. Diabetics do not produce the correct amount of insulin, an essential protein that allows the body to process sugar in the bloodstream.
The most common form is Type II, usually found in older people and often treated with tablets and careful diet. Type I diabetes is a more severe form of the disease and is usually found in younger people.
In research described as "remarkable" by Dr Jerrold M Olefsky of the University of California, San Diego, in an accompanying technical assessment, the team identified an "insulin analogue", a simpler form of insulin that was about 30 per cent as active as the original.
They took the piece of genetic code that could make the analogue and "pasted" it, using genetic engineering, into a virus that causes the common cold. This was used to infect the rodents and transfer the insulin analogue into them.
Once in place the imported genetic code started producing the insulin analogue and blood sugar levels dropped down to near normal levels, the research team reported. The analogue worked much the same as normal insulin, with levels rising and falling automatically to match blood sugar levels.
"But rodents are quite different from humans and with respect to maintaining glucose [sugar] levels, and extending these results to human physiology may prove a challenge," Dr Olefsky said. Even so the research "is a definite step forward" in the development of a permanent and injection-free treatment for diabetes.
