From Harvard Magazine:
Xander University Professor Douglas Melton and postdoctoral fellow Peng Yi today announced that they have identified a hormone that induces reproduction of new insulin-producing beta cells in the pancreas, offering hope for a better way to treat type 2 diabetes. The disease, which is usually caused by lack of exercise and obesity, affects approximately 26 million Americans. In type 2 diabetes, the pancreas doesn’t produce enough insulin to be able to manage a patient’s blood sugar; the patient also becomes increasingly resistant to insulin’s effects. Melton—co-scientific director of the Harvard Stem Cell Institute—and Yi initially demonstrated the effectiveness of their new treatment in mice but have since found evidence that the same pathways on which the hormone works are active in humans. Melton hopes that betatrophin, the newly discovered hormone, will be approved for clinical testing in humans within five years. “If this could be used in people,” says Melton, co-chair of the University’s Department of Stem Cell and Regenerative Biology, “it could eventually mean that instead of taking insulin injections three times a day, you might take an injection of this hormone once a week or once a month, or in the best case maybe even once a year.” The hormone works by causing beta cells to divide. Normally, only one in a thousand or one in ten thousand beta cells divides in a day. Betatrophin increased the rate of division 30 times in insulin-resistant mice. These mice began with only 10 percent to 15 percent of the normal complement of beta cells. In an experiment using betatrophin, Melton was able to triple those numbers in a week.
Melton has been seeking a cure for diabetes ever since his son, and later his daughter, were diagnosed with type 1 diabetes, a disease in which the immune system attacks and kills off insulin-producing beta cells. Melton said in an interview that this latest discovery is not likely to be an effective treatment for type 1 diabetes because it requires existing beta cells in a patient: the treatment works by causing those cells to divide. But he says it might help in the early stages of type 1 diabetes, before all the beta cells had been eliminated. And it holds further promise: if in the future scientists find a way to stop the immune attack on beta cells, then betatrophin might become an important treatment for even the type 1 form of the disease.