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April 14, 2010 -- Researchers have added a new element to the "artificial pancreas" that may help the 3 million Americans living with type 1 diabetes better control their blood sugar (glucose) levels and stave off diabetes-related complications.
The new findings appear in Science Translational Research.
The hope is that an artificial pancreas will do what the pancreas cannot do among people with type 1 diabetes: produce the hormone insulin.
Research on the development of an artificial pancreas has traditionally focused on delivery of insulin. But the new design introduces another hormone called glucagon to the equation.
People with type 1 diabetes do not produce any insulin, which is needed to regulate blood sugar levels. Glucagon is another hormone that is produced by the cells in the pancreas to help control blood sugar levels. People with diabetes do produce glucagon, but not efficiently. As a result, they are at risk of developing low blood sugar (hypoglycemia) in response to excess insulin.
The artificial pancreas described in the new study comprises a continuous blood sugar monitor and two pumps that communicate with each other via a computer.
"We measure blood glucose on a laptop and have pumps to deliver insulin and glucagon, but there is continuous glucose monitoring, which will send wireless signals to the laptop that wirelessly controls the pumps that give insulin and glucagon," says study researcher Steven J. Russell MD, PhD, an endocrinologist at Massachusetts General Hospital Diabetes Center in Boston. "It adds the capability to give glucagon, and that hasn't been available before and is pretty important."
"It is well known that people with type I diabetes don't make insulin, but they also have a deficiency in making glucagon," Russell tells WebMD.
If researchers get this right, "the benefits will be that people spend a lot less time thinking about and worrying about their diabetes and parents will worry less about their children with diabetes when they are away," he says. "It will improve blood glucose control and reduce risk of developing complications of diabetes."
Uncontrolled blood sugar levels wreak havoc on the body, causing such complications as eye, nerve, and kidney damage among people with diabetes.
The new study looked at the two-hormone artificial pancreas system in 11 adults with type 1 diabetes. Researchers monitored participants' blood sugar levels for 26 hours. They found that there was a great variation in insulin levels. As a result, some participants developed low blood sugar. They then tweaked an algorithm to provide a slower insulin absorption and prevent hypoglycemia. It worked.
"The results are very encouraging and suggest that an artificial pancreas using insulin and glucagon in small doses works very well in a broad range of people over 18 with significant variability in insulin absorption rates," says study co-researcher Edward R. Damiano, PhD, an associate professor of biomedical engineering at Boston University."The new system may provide much better glucose control and very little hypoglycemia risk."