As of Tuesday, July 16, 2013
DEAR DOCTOR K: I have diabetes. I read that scientists had made a major discovery about how people with diabetes could naturally make more insulin. How excited should I be about this?
DEAR READER: I believe you are referring to a discovery by the laboratory of a colleague here at Harvard, Dr. Douglas Melton. It’s a great story.
About 20 years ago, Dr. Melton was a young scientist who was studying the basic biology of how cells work. He wasn’t focusing on any particular disease. Then his infant son developed severe Type 1 diabetes.
That’s a disease in which the body’s immune system attacks the pancreas, a spongy little organ inside the abdomen. The attack destroys the pancreas cells that produce insulin, called beta cells. As a result, the body does not have enough insulin, the hormone that directs blood sugar — our body’s main source of energy — into our cells. Sugar levels rise in the blood, and the body’s cells don’t get enough energy.
Prompted by his son’s illness, Dr. Melton turned the focus of his scientific work to trying to cure diabetes. First, he and other scientists discovered, to their surprise, some good news and some bad news. The good news: The pancreas did have a way of making new beta cells. The old cells could divide, forming young beta cells. The bad news: The pancreas didn’t seem able to produce new beta cells in nearly sufficient amounts to make up for the cells killed by diabetes.
Undiscouraged, Dr. Melton reasoned that if older beta cells could be prompted to make new young beta cells — in any amount — then the body probably had chemical signals that drove the process. He began to search for them.
In early May 2013, Dr. Melton reported in the prestigious scientific journal Cell that his research team had indeed found such a chemical signal, a hormone, in mice. The hormone is made in the liver and in fat, and travels through the blood to the pancreas. It is able to coax an old, burned-out pancreas to make lots of new young beta cells. In mice with diabetes, the treatment caused a dramatic improvement in blood sugar. Dr. Melton named the hormone that he discovered betatrophin.
It will, of course, take much more research in mice and then in humans to determine if this newly discovered hormone can serve as a treatment for human diabetes. So, to answer your question, it’s too soon to get excited.
Still, this is just the latest example of an even larger scientific discovery that has played out over the past 20 years. The human body has much greater power to repair itself naturally than we once imagined. Scientists just need to discover a few tricks to help stimulate the body’s own natural healing, as in this case.
To transform this important discovery into a new treatment for diabetes we need more medical research. Encourage your members of Congress to push for more funding.
Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.