Study Tests Powdered Insulin to Prevent Diabetes
April 21, 2015 — Swallowing a daily dose of insulin is safe, and it may act like a vaccine to prevent type 1 diabetes, a small new study shows.
If the results can be repeated in larger and longer trials, the approach may one day be used to help young children at high risk of the disease avoid getting diabetes.
Type 1 is an autoimmune disease. The body attacks and destroys islet cells in the pancreas that make insulin, a hormone that controls blood sugar.
The condition affects about 3 million adults and children in the U.S. And no one is sure why, but like allergies and other kinds autoimmune conditions, it’s on the rise. One study found the rates of type 1 diabetes in children under age 5 had climbed 70% between 1995 and 2004.
The immune system’s assault on the islet cells happens in several steps. Before the body attacks those cells, it makes proteins that mistakenly flag insulin as foreign and dangerous. In a sense, the body becomes allergic to itself.
Blood tests can spot this early immune breakdown. Right now they aren’t routinely given, though, because doctors don’t have a way to stop the process once it starts.
But scientists wondered if giving children insulin the way you might treat someone with a food allergy — by feeding them tiny amounts of the problem food to build up a tolerance — might prevent the attack.
Defusing the Assult
Researchers say when proteins are introduced to the body through the mouth or nose, or when they’re absorbed through the skin, the immune system learns to see them as safe and will later tolerate them.
“The immune system in these places is there to learn to turn itself off, not on,†says researcher Ezio Bonifacio, PhD, a professor of diabetes at the Center for Regenerative Therapies in Dresden, Germany.
One risk in this approach, though, has been that the insulin might cause a dangerous drop in blood sugar.
Studies in mice bred to get type 1 diabetes have shown that insulin can defuse the immune attack and prevent diabetes, without any effect on blood sugar. But previous studies that have tried the same approach in people were less successful. Experts think it might be because the insulin was given too late in the type 1 disease process or at too low a dose.