A race is on to find a way to cure Type 1 diabetes by regenerating the insulin-producing cells in the pancreas that are lost in the disease. Without them, the body is unable to metabolize sugar, forcing patients to compensate by injecting themselves with insulin several times a day.
One popular strategy has been to get embryonic stem cells or induced pluripotent stem cells -- which can theoretically become any type of human cell -- to grow into these so-called beta cells. Last year a Harvard team took a shortcut and transformed normal pancreas cells into beta cells by activating a trio of genes.
On Thursday, a team of European and American researchers showed that pancreatic cells in diabetic mice could be reprogrammed into beta cells by turning on just one gene, called Pax4.
The scientists gave the mice the chemical streptozotocin, which killed off their beta cells while preserving other types of pancreatic cells. Then they activated the Pax4 gene, which does most of its work during fetal development.
They found that the gene converted so-called alpha cells -- which normally make the hormone glucagon -- into insulin-producing beta cells. Beta cell levels were eight times higher in treated mice than in untreated control subjects, said the study(09)00639-4 published in Friday's edition of the journal Cell.
For some reason researchers don't yet understand, the therapy worked best on mice less than 1 month old. For them, the treatment completely counteracted the symptoms of Type 1 diabetes.
In fact, it may have worked too well, leaving the mice with a shortage of alpha cells. Before this approach can be tried in humans, scientists need to figure out a safe way to turn on the Pax4 gene -- and shut it off.
"A lot of ifs remain before we will know whether it could be taken to the clinic," said the study's lead author, Patrick Collombat of the Max Planck Institute for Biophysical Chemistry in Germany.
But for Type 1 patients who take daily insulin injections, he said in a statement, this much is clear: "We need a better treatment. We need to find a way to regenerate beta cells."