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Diabetes is a disorder of metabolism, in which the ability of the body to transport sugar into its cells for energy is disrupted. As a result, the sugar levels outside the cells rise, resulting in elevated blood sugar levels.

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Kathryn Thrailkill, M.D., chief of pediatric endocrinology at the UK Chandler Medical Center, presented the findings at a recent American Diabetes Association meeting.

Recombinant human insulin-like growth factor-I (rhIGF-I) is being evaluated as a potential therapy for the treatment of Type I diabetes, or insulin-dependent diabetes, an autoimmune disease that accounts for 5-10 percent of diagnosed diabetes in the U.S. and develops mostly in children and young adults.

The insulin-like growth factor is being developed as an adjunct to insulin therapy for individuals whose diabetes is not adequately controlled by insulin alone. "There haven’t been any new treatment options besides insulin. There have been new forms of administering it, but no new treatments. This is the first pharmacological treatment to come along," Thrailkill said.

A dual hormonal replacement therapy approach -- rhIGF-I used in combination with insulin -- will allow the combined, complementary actions of these two hormones to act.

In Phase II of the study, which included 18 study sites, rhIGF-I worked to restore overall metabolic balance in the body by simultaneously improving glucose control and insulin sensitivity. It also may affect the body’s composition, promoting more muscle mass, Thrailkill said. In higher doses, rhIGF-I produced some side effects, such as swelling and jaw pain, effects that were not as common in lower doses.

Developed by Genentech, Inc., a biotechnology company, rhIGF-I has been tested in patients with Type I diabetes, ranging in age from 11 to 65 years, with an average age of 29. Thrailkill is one of three primary researchers evaluating the treatment in Type I diabetes from the beginning.

The current phase of the study (Phase III), which involves 100 institutions, began in January and will conclude at the end of 1998. UK has seven patients, ranging in age from 8 to 17 years, enrolled in the study, although the study is open to anyone from ages 8-65.

Diabetes is a disorder of metabolism, in which the ability of the body to transport sugar into its cells for energy is disrupted. As a result, the sugar levels outside the cells rise, resulting in elevated blood sugar levels.

Most of the food we eat is broken down by digestive juices into a simple sugar called glucose, which is the main source of fuel for the body. Under normal conditions, the glucose then passes into the bloodstream, where it is available for body cells to use for growth and energy. For glucose to enter the cells, insulin -- a hormone produced by the pancreas -- must be present. When we eat, the pancreas releases the right amount of insulin to move the glucose from our blood into our cells. But in people with diabetes, the pancreas either produces little or no insulin, or the body cells do not respond normally to the insulin that is produced. As a result, glucose levels build up in the blood, glucose is spilled in the urine, and the body is deprived of a critical source of fuel.

In Type I diabetes, the body’s immune system attacks insulin-producing beta cells in the pancreas and destroys them. The pancreas then produces little or no insulin. People with Type 1 diabetes need daily injections of insulin to live.

IGF-I, along with insulin and IGF-II, is one of three naturally-occurring hormones capable of enabling cells to transport sugar inside and thereby lowering blood sugar in humans. IGF-I and insulin appear to act together to regulate normal glucose levels. Both systems are disrupted in diabetes.

The objective, Thrailkill said, is to find better ways to improve blood sugar control to lessen the long-term effects of the disease, including blindness, heart disease, stroke, kidney failure, and nerve damage that can lead to amputations.

By Vikki Franklin