VANCOUVER — For the first time ever, University of B.C. scientists have used human embryonic stem cell transplants to reverse Type 1 diabetes in mice with the disease, giving hope to about 300 million people around the world who suffer from the chronic disease.
A 13-member team, whose milestone work is published in the journal Diabetes, shows that after transplantation, the stem cells matured into insulin-secreting, pancreatic beta-cells. The cells automatically sensed blood sugar levels to release the right amount of insulin and a few dozen diabetic mice were gradually weaned off insulin given to them over a period of months.
Insulin is produced by beta-cells to to help the body absorb sugar and use it for energy.
Essentially, the mice were cured of their diabetes by placing the body back in charge of regulated insulin production as it is in healthy, non-diabetics, said lead author Timothy Kieffer.
It took about four to five months for the [stem] cells to become functional in our experiments and the mice were able to maintain good blood glucose levels even when fed a high-glucose diet, said Kieffer, a UBC professor in the department of cellular and physiological sciences.
Type 1 diabetes otherwise known as juvenile diabetes is an autoimmune disease in which a patients immune system kills off insulin-producing cells in the pancreas. About 10 per cent of diabetics are Type 1 and typically, they must inject themselves with insulin or use pumps to control their blood glucose levels.
While pancreatic islet cell transplantation pioneered at the University of Alberta several years ago has been shown to be an effective way of reducing dependence on insulin injections, the treatment is costly and cumbersome as it requires donor cells from cadavers, which are always in short supply. As well, islet cell transplant patients must forever take anti-rejection drugs that can cause organ damage.
In the study methodology, mice were anesthetized and then injected with millions of cells derived from stem cells which were placed under the left kidney area.
Although the research showed that stem cells may one day provide a cure for diabetes, it also revealed hurdles to overcome before agencies like the Food and Drug Administration in the United States or Health Canada can approve the therapy.
For example, some mice developed bone or cartilage in areas where the cells were inserted, an unacceptable side-effect that future experiments must resolve.