Cure for diabetes comes step closer

Experimental gene therapy used to treat disease in mice, DAMIEN HENDERSON
A cure for diabetes has been developed in mice using experimental gene therapy that may eventually be applied to humans.

Using genetically-altered liver cells, American researchers have stimulated the production of insulin in the rodents, ridding them of the condition for at least four months. It was described by one leading charity as a "major step forward" in the fight against the condition.

People with diabetes have a lack of insulin, the hormone that regulates blood sugar levels and helps glucose sugar enter blood. Around 120,000 people have been diagnosed with the condition in Scotland.

Research was conducted into transplanting "islets", the small bodies normally found in the pancreas which produce insulin, but has been dogged by the difficulties of finding a compatible donor and requires the patient to take powerful immunosuppressive drugs.

The research, led by Professor Lawrence Chan at the Baylor College of Medicine in Houston, Texas, however, used the mice's own liver cells to generate insulin. Prof Chan said the experiment was an important "proof of principle". By introducing a gene to the liver cells, they were induced to become beta cells, which produce insulin and three other hormones and are normally found in islets.

A spokesman for Diabetes UK, the charity representing the 1.4 million UK sufferers, said: "The fact it has been achieved in mice does mean there's an awful lot more work to be done before it may be applied to humans, but it does sound like a significant breakthrough."

A cure for both type 1 and type 2 diabetes could potentially be found. In type 1, or insulin dependent diabetes, diabetics produce virtually no insulin because their islets have been destroyed by their own immune system. In type 2, the body does not produce enough insulin or respond to the hormone normally. In more severe cases, if untreated, glucose levels build up in the blood, causing the patient to lapse into a coma and die.

In the research, a virus was used to carry the beta cell gene into the mouse liver cells which, on its own, part-ially corrected the disease. When combined with a beta cell growth factor, a biochemical that promotes growth, the mice were cured for at least four months.

The modified liver cells also produced glucagon, somostatin, and pancreatic polypeptide hormones that are thought to play a role in controlling insulin production and release. The results were reported in the online edition of the journal Nature Medicine.

Martin Maxwell, who works for the Edinburgh branch of Diabetes UK, said: "For young people who are newly diagnosed, I think the main advantage is that they would only need treatment every six months or so.

"Youngsters go through a stage in adolescence where they become quite nonchalant about taking their injections, and that's when they're heading for trouble."