Type 1 diabetes mellitus, also known as juvenile diabetes, is a devastating autoimmune disorder. In type 1 diabetes, the immune system destroys certain cells in the pancreas that secrete the hormone insulin, which the body needs in order to regulate blood sugar. Recent research is allowing doctors for the first time to investigate ways that may one day help prevent type 1 diabetes.
The Cause of Type 1 Diabetes
Type 1 diabetes is called juvenile diabetes because onset frequently happens during childhood, though sometimes onset is in adulthood, according to the American Diabetes Association. Insulin is a metabolic hormone that causes the body’s cells to take up the sugar glucose from the blood and store it as the starch glycogen. Insulin is produced in the beta cells of the islets of Langerhans, located in the pancreas.
The current hypothesis behind type 1 diabetes is that certain of the immune system’s T cells normally have a tendency to react against the beta cells, but are held in check by other T cells called regulatory or suppressor T cells. When the regulatory T cells are deficient, the other T cells, called autoreactive T cells because they react to the body’s own self, start an inflammatory response against the beta cells, destroying them.
Cytokines, chemicals used by the immune system for communication, probably play a central role, according to this hypothesis. There is evidence that autoreactive T cells produce type 1 cytokines and regulatory T cells produce type 2 and type 3 cytokines, so type 1 diabetes may be caused by an imbalance among these cytokines.
Most of the research behind this hypothesis took place in animals; there is still little research into human subjects. Even so, researchers are investigating the potential for type 1 diabetes prevention for juveniles and adults based on this hypothesis.
Type 1 Diabetes Prevention
Researchers hope one day to be able to prevent type 1 diabetes in at-risk individuals. One possible method is the administration of beta cell autoantigens. These are chemical markers found on the beta cells that trigger the autoreactive T cells. The hope is that the autoreactive T cells will be occupied by the introduced autoantigens and will not be as capable of attacking the actual beta cells.
Another potential preventive measure might focus on adjusting the immune system’s cytokine balance. If type 1 diabetes results from overproduction of type 1 cytokines and underproduction of type 2 and type 3 cytokines, preventive therapy might involve coaxing the immune system into producing relatively less of the type 1 cytokines and relatively more of the type 2 and type 3 cytokines.
Rabinovitch, A. & J. S. Skyler, 1998. “Prevention of type 1 diabetes.” Medical Clinics of North America 82(4):739-55.