Alpha-GalCer. Type 1.
By Suzanne Rostl@r
NEW YORK, Aug 30 (R@utrs Health) - Two teams of scientists have identified a compound found in marine sponges that could prevent type 1 diabetes, according to two reports published in the September issue of Nature Medicine.
The compound, alpha-galactosylceramide (GalCer), binds to certain receptors on natural killer T cells (NKT cells) and stimulates the production of proteins that prevent the insulin-producing cells of the pancreas from being destroyed.
NKT cells are part of the immune system and their numbers decline in people with type 1 diabetes, although it is not clear why, Dr. Terry L. Delovitch, senior author on one of the studies, told Reuters Health.
But alpha-GalCer injected into non-obese diabetic mice prevented the mice from developing diabetes and prolonged the survival of islet cells that were transplanted into newly-diabetic mice. The islet cells of the pancreas produce insulin.
"These findings raise the possibility that alpha-GalCer treatment might be used therapeutically to prevent the onset and recurrence of human type 1 diabetes," Delovitch, of the University of Western Ontario, Canada, and an international team of scientists conclude in their report.
Delovitch said that the compound has been deemed safe in preliminary studies of patients with colorectal cancer. But further research is needed to show that alpha-GalCer is effective in humans before the compound is given to patients with type 1 diabetes. These studies, Delovitch said, will take up to 7 years.
In the second study, researchers garnered similar results when they gave alpha-GalCer to mice that were genetically predisposed to develop diabetes.
Left untreated, about 90% of the mice should have developed type 1 diabetes. But only 10% to 20% of mice treated with alpha-GalCer developed the disease, according to the results.
"For humans this would mean that you would need to start treatment before severe symptoms of diabetes have developed," Dr. Luc Van Kaer, the study's senior author, told Reuters Health. "Alternatively, individuals that are at (genetic) risk for developing diabetes could be treated."
He said that alpha-GalCer was originally isolated by a Japanese company that is currently conducting clinical studies on the treatment of cancer in humans.
"This (compound) may have potential for the treatment of a number of human diseases," said Van Kaer, of Vanderbilt University in Nashville, Tennessee.
Type 1 diabetes is a disease in which the body's immune system attacks the insulin-producing cells of the pancreas. Insulin is the hormone that deposits glucose (sugar) from the blood into cells throughout the body to use as energy. People with type 1 diabetes rely on daily insulin injections to control their blood sugar.
SOURCE: Nature Medicine 2001;7:1052-1062. |
