Pills to replace insulin shots could spring from experiment

People with diabetes might someday be able to take insulin in pills rather than shots, using an approach in which the drug is put into tiny plastic beads, a study in mice suggests.

The approach might also help scientists plant genes in people to treat disease, researchers said.Normally, insulin taken by mouth would be destroyed by digestive juices and not absorbed by the intestine. So it wouldn't reach the bloodstream to travel to the tissues where it can act to control blood sugar levels.

The mouse experiments used plastic beads smaller than the width of a human hair. The beads protected the insulin and delivered it to the bloodstream. The insulin escaped as the plastic disintegrated.

Edith Mathiowitz of Brown University and colleagues demonstrated the approach in today's issue of the journal Nature. Normally, when a mouse is injected under the skin with a liquid sugar dose, its blood sugar levels rise. But when mice got that injection and then swallowed beads filled with insulin, their blood sugar levels didn't budge.

Similarly, after mice swallowed DNA in beads, scientists found that one of the genes in the DNA was taken up by the cells of the intestine and liver, and that the gene was active. That holds promise for treating diseases caused by faulty genes, Mathiowitz said.

The National Institute of General Medical Sciences, a part of the National Institutes of Health that helped pay for the study, said it will take years of further research before the approach could be used in people.