THE COMPOUND is a mimic of insulin, the natural hormone
that allows the body to metabolize sugar, the researchers said.

"This could potentially be used to replace insulin shots in diabetics," said Dr. Bei Zhang of Merck, the lead author of a study to be published Friday in the journal Science. She cautioned, however, that "it is still very early," and that years of research remain before the compound could be tested in humans.
About 175 million people worldwide, nearly 16 million of them in the United States, suffer from diabetes. It can lead to blindness, heart disease, limb loss and kidney disease.
There are two types.
Type-I or juvenile diabetes is caused by the destruction of insulin-secreting cells in the pancreas.
Type-II, or non-insulin dependent diabetes mellitus (NIDDM), affects many more people and is caused when the body becomes resistant to insulin's effects.
In both types, cells are unable to absorb enough glucose, a sugar, to work properly. Insulin is key to this and when there is either not enough, or the cells are not responding to it, the system goes haywire.

Millions of diabetics have to inject insulin daily to control their blood sugar levels. There are also drugs that help enhance the effects of insulin.
Insulin is a large molecule that is destroyed in the stomach, so it must be injected.
Scientists have been searching for a substitute that can be swallowed.
The newly discovered compound, called L-783,281, was found by a team that laboriously tested 50,000 substances collected from around the world, checking each one for its ability to mimic the action of insulin.
L-783,281 was found to be promising in test tube studies, so the researchers carried it to the next step - testing on animals.
Two strains of mice that naturally develop diabetes were treated with the compound and tests showed that L-783,281 helped the mouse cells to take glucose, or sugar, from the blood stream. I
it did not seem to harm the mice. "Long-term treatment (up to 15 days) with therapeutic doses of L-783,281 did not affect food intake, body weight, organ weights or blood chemistry," they wrote.
Zhang said the compound works in much the same way as insulin. L-783,281 links up with a specific molecule on the surface of each cell. This activates an enzyme that sets off a series of biological steps, enabling the cells to absorb and use sugar.

Zhang said that, unlike insulin, L-783,281 can be taken as pills. The compound can be absorbed by the digestive system and still act on the cells of the body. Insulin is destroyed by digestion and, for this reason, must be given by injection, a regimen that is often difficult for patients to accept.
Dr. Robert Goldstein, vice president of research at the Juvenile Diabetes Foundation, said the discovery of L-783,281 "is a real advance" in diabetes research.
"It offers the promise of an alternative approach in which patients would not have to have insulin shots," he said. But Goldstein cautioned that a great deal more study is needed before L-783,281 could be safely tested on humans.
"This still needs a lot of work," he said.

Merck, like many other companies, has spent years collecting samples of plants and animals from around the world for use in testing as drugs.