To run a car, you need two types of petroleum products: gasoline and motor oil. If you only use gas, the car will run, but its engine eventually will blow out because the oil isn’t there to lubricate it. Although they’re not exactly sure how it works yet, researchers have discovered that a hormone traditionally considered a useless byproduct of insulin might help people with diabetes keep their bodies in running order longer by fending off complications.

Researchers will gather Oct. 20 for the Third Annual International Motor City Diabetes Symposium to discuss connecting-peptide (or C-peptide) therapy, which has shown promise in European clinical trials for limiting the damaging effects of diabetes complications. A press conference to release the details of this cutting-edge research as well as a consensus statement on where this work is heading will be at 4:45 p.m. on Oct. 20 in Dearborn’s Automotive Hall of Fame.

People with Type 1 diabetes, or insulin-dependent diabetes, don’t produce proinsulin, a molecule manufactured in the pancreas that can be divided into two parts: insulin, a substance that regulates the body’s sugar levels, and the C-peptide.

Traditionally, blood tests use C-peptide levels to measure how much insulin is in a person’s system, because there is a one-to-one ratio for insulin and C-peptide. Treatment for Type 1 diabetes involves replacing insulin to allow the body to properly metabolize food, however, researchers now are looking at the effects of replacing both insulin and C-peptide.

In Europe, small, short-term clinical studies in humans with Type 1 diabetes have shown C-peptide therapies improve kidney function, blood flow and autonomic nerve function, which in turn improve functioning of the heart, bowels and sex organs. Similar studies in rats conducted by WSU Professor of Pathology and Neurology Anders Sima, MD, PhD, have shown neurological complications can be reversed using C-peptide.

“This is a major advancement in how to treat Type 1 diabetes in order to prevent and potentially treat complications. It’s the complications that cause morbidity and mortality,” said Dr. Sima, director of the Morris J. Hood Jr. Comprehensive Diabetes Center, adding that C-peptide therapy also may be useful in treating people who have very late-stage Type 2 diabetes.

Diabetes and its complications is the fourth-costliest health-care issue in the United States, costing an estimated $130 billion per year. In addition to being a major cause of blindness, renal dialysis and renal transplant, nearly 80,000 amputations each year result from nerve complications. About 17,000 U.S. citizens die each year as a result of Type 1 diabetes or its complications; an additional 170,000 people die of Type 2 diabetes.

If further research confirms these early findings, C-peptide easily could be integrated into a treatment regimen. Drug companies already manufacture C-peptide as a byproduct of insulin. The hormone simply could be added into the same injections diabetics already administer, Dr. Sima said.

Further, C-peptide therapy is the least invasive of any promising new treatments for Type 1 diabetes. Other promising treatments include pancreatic transplants, stem-cell transplants and beta-cell transplants, but these therapies are limited by the availability of transplantable tissue and the risk of rejection by the immune system. Also, these procedures require a person’s immune system to be suppressed, which carries with it a number of adverse effects.

“Given the data, I think it’s realistic to expect that we can directly translate experimental findings to the practical treatment options,” Dr. Sima said.

Large-scale trials are expected to begin in Europe early next year. Leading C-peptide scientists from around the world, including the Karolinska Institute in Sweden, will gather at Dearborn’s Automotive Hall of Fame on Oct. 20 to present their findings and discuss yet-to-be-discovered aspects of C-peptide, such as the actual mechanism that seems to prevent and repair complications.

The researchers plan to fashion a consensus statement to determine the direction of future research, said George Grunberger, MD, medical director of the Hood Center

“It’s becoming very clear that C-peptide is not garbage, as many have thought over the years, but in fact, is very important in clinical treatment,” he said. “This is a potential breakthrough for the 1 million Americans who suffer from Type 1 diabetes.”