Diabetics could soon 'grow their own insulin'

Scientists may have found a way of curing diabetes - at least in men.

They have used tiny slivers of testicular tissue to make millions of healthy replacements for the faulty cells behind the condition.

In experiments on mice, grafts of the lab-grown pancreatic cells produced enough insulin to control blood sugar levels in diabetic mice.

Although the work is at an early stage, the American researchers believe it could lead to a cure for men and boys with type 1 diabetes in perhaps just five years.

However, British experts have urged caution, saying that any cure is still many years away.
Diabetes occurs when the pancreas does not make enough insulin, a hormone key to the conversion of sugar into energy, or the insulin that is made does not work properly.

The 250,000 Britons with type1, or childhood, diabetes do not make any insulin at all and so need to take regular injections to stop blood sugar levels from fluctuating wildly.
In the latest study, immature cells that would normally go on to form sperm were turned into healthy insulin-producing cells.

The researchers, from Georgetown University Medical Centre, in Washington DC, started with tiny samples of tissue from human testicles.

Using a cocktail of vitamins and growth factors, they transformed them first into stem, or ‘master, cells, and then into the beta islet cells that produce insulin in the pancreas.
The process took around five weeks, the American Society of Cell Biology’s annual conference heard.
Layers of pancreatic cells were then grafted onto diabetic mice, where they produced enough insulin to control blood sugar levels for a week.

While this might not seem long, the researchers say it should be possible to make the cells work for much longer - and for them to produce enough insulin to benefit human diabetics.
Researcher Dr Ian Gallicano believes the testicular cells, or spermatogonial stem cells, could succeed whether other potential diabetes cures have failed.

He said: ‘No stem cells, adult or embryonic, have been induced to secrete enough insulin yet to cure diabetes in humans, but we know that spermatogonial stem cells have the potential to do what we want them to do, and we know how to improve their yield.’

Using a man’s own cells as the source of the treatment would sidestep any chance of the tissue being rejected by the body.
They hope to test the technique on men for the first time within months. If large-scale trials show it to be safe and effective, the transplant technique could be in widespread us in as little as five years.
Adapting the technique to eggs instead of sperm could allow female diabetics to eventually benefit too, the researchers believe.
Although the work is focused on type 1 diabetes, the technique may also be applicable to some cases of type 2 diabetes, the more common form of the condition.

This type of diabetes tends to affect people over 40 and occurs when not enough insulin is produced, or the insulin that is made doesn't work properly.
Chris Mason, professor of regenerative medicine at University College London, welcomed the breakthrough but cautioned it may be many years before patients can benefit.

He said: ‘Yet again, a world-class team of scientists has suggested another novel cell-based therapy for diabetes.
‘The question is how to turn such great discoveries into safe effective cures for people with diabetes - a process that has a high failure rate and takes years. It is time for less hype and more pragmatism.’
The charity Diabetes UK was more blunt, describing the research as ‘a tiny, incremental advance’ in the search for a cure for diabetes.

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