Big breakthrough in diabetes

By Mike Bowerman

The University of Calgary announced a breakthrough in research on Type 1 diabetes by Faculty of Medicine researcher Dr. Ji-Won Yoon.

"After 25 years of trying to find causes and cures for diabetes, this discovery is one of the high points of my scientific career," said Yoon. "We expect this breakthrough to pave the way for us to develop a future therapy which, we hope, will cure diabetes in people."

Type 1 diabetes, commonly known as juvenile diabetes, results when the body’s immune system destroys insulin-producing cells in the pancreas, leaving the body unable to regulate blood sugar levels. To compensate for the lack of insulin, the researchers injected a genetically modified virus carrying a section of genetic code into the livers of lab animals, where the virus then transported the gene into target cells to produce a substance nearly identical to insulin.

"One injection results in almost full remission of Type 1 diabetes," observed Yoon. "There is no detectable side effect."

The research is groundbreaking in applying gene therapy to diabetes, but significant work needs to be done before any human applications can be realized. Director of the Julia McFarlane Diabetes Research Centre Dr. David Lau applauded the innovations of his peers while noting that challenges lie ahead.

"This conceptual breakthrough means paving the way for future research endeavours," said Lau. "We’re still quite a few years from considering clinical trials using gene therapy in humans because of a number of barriers that we have to overcome."

These barriers include finding ways to produce more of the transporting virus and testing for side effects in laboratory tests on larger animal species. The novel approach of using a virus to transport the gene to target cells will also require further scrutiny, according to Yoon.

"Viruses are not as benign as you think," cautioned Yoon. "Even though they may not cause any harm to the animals, they may potentially do some harm to humans. Even a very little bit of harm could be serious, so we have to overcome some of these barriers."

Investigating possible repercussions could take six to eight years, but innovations in the approach bode well for success where others have failed.

"What others have done is consider transplanting eyelets or the pancreas into individuals with Type 1 diabetes," observed Lau. "[But] the underlying disease process of auto-immune destruction still continues so the insulin-producing cells will be destroyed. By using gene therapy, which introduces a gene that produces insulin and is sensitized by the fluctuating levels of sugars, the gene can be turned on and off and is not affected by the underlying disease process."

Around 250,000 Canadians have Type 1 diabetes. Although there are other treatments available the disease still takes a serious toll. One to four daily injections of insulin costs an average of $300 per month. Over a lifetime this can cost upwards of $200,000 while complications including blindness, heart and kidney problems are still a possibility. If Yoon’s work can be translated into a comparable therapy for humans, it will mean a great reduction in not only health care costs but an increased quality of life for sufferers.

Dr. Yoon gave a significant amount of credit for the experimental portion of the research to his colleague in Korea, Dr. Hyun Chul Lee, at Yonsei University, College of Medicine in Seoul, Korea. Critical funding and support was supplied by the Alberta Heritage Foundation for Medical Research, Julia McFarlane Diabetes Research Centre, Foothills Diabetes Association and Brain Korea 21 Project.