diabetics gene

The Mouse That Roared: preventing diabetes in children

by Barry Bittman, MD

There’s an exciting approach on the horizon for preventing childhood diabetes that may someday take the form of a vaccine.

In last week’s column, I presented an important breakthrough concerning a fungus found in the jungle that can mimic the effects of insulin and potentially benefit millions of individuals throughout the world with diabetes. On the heels of that discovery, researchers at the University of Calgary just announced what may very well be the most important breakthrough for the prevention of childhood diabetes, a disease that affects more than 1 million individuals in our nation.

In the journal Science, Dr. Ji-Won Yoon announced his team’s discovery of a gene in rodents that always get diabetes. His team found that insulin-producing cells in the rat’s pancreas release a protein called GAD or glutamic acid decarboxylase. The release of this substance literally sends up a red flag¾ an announcement that signals our body’s immune system to attack. And attack it does!

Specialized immune cells that normally serve us well instantly heed the call. Killer T-cells that target viruses and cancer cells suddenly spring into action and attack the marked pancreatic cells. As a result, the insulin-producing cells are destroyed, thereby rendering the body unable to handle sugar in the bloodstream.

The result is Type I diabetes, a devastating disease that mostly affects children with approximately 30,000 new cases discovered each year.

Yet based upon this discovery, Type I diabetes may become a disease future physicians might never see. According to Dr. Yoon, “We found that if we suppress GAD expression in the pancreatic cells, then we can prevent diabetes. It is that simple.”

Simple or not, you’re probably asking yourself how such a vaccine might work. The principle is straightforward, yet a great deal of research is necessary before it becomes available for people. Essentially, it works like this:

Small quantities of GAD would be injected into children at an early age. The immune system would progressively get accustomed to the substance, and Killer T-cells would eventually learn to tolerate its presence. Ultimately, when beta cells in the pancreas turn on production of GAD, they wouldn’t incite Killer T-cells to attack. In effect, these insulin-producing cells would be tolerated by the body’s defense system.

Based upon this research, another strategy for preventing Type I diabetes might someday include identifying the gene before the disease develops and utilizing other immune-based strategies. In fact, researchers at leading universities throughout the world are actively studying numerous approaches for treating a host of disorders termed “autoimmune” diseases. These conditions including Systemic Lupus and Rheumatoid arthritis occur when our immune system attacks certain cells in our bodies. A logical approach is to selectively turn off our immune defenses to prevent our own cells from being attacked.

It is important to realize that GAD does not affect all diabetics. More than 15 million adult Americans with Type II diabetes are unaffected by this gene. In contrast to Type I diabetes, Type II typically results from insensitivity to the insulin the body is producing.

Yet, for millions of potential victims of a disease that is no less than devastating, the discovery of GAD might herald one of the most exciting medical breakthroughs of the new millennium. Although the vaccine may take 10-15 years to successfully introduce, the potential for preventing Type I diabetes is now a reality.

The GAD breakthrough is just another example of the information hidden in our DNA that scientists are now deciphering with modern technology. Understanding the genetic basis for many diseases will enable researchers to make an early diagnosis, even in the womb, for illnesses that thus far have been untreatable. Through the cooperative efforts of Dr. Yoon’s team, and a rodent that always gets diabetes, we’re one step closer to eradicating one of the foremost challenges of modern medicine¾ Mind Over Matter!