|Thursday September 21, 2:44 pm Eastern Time |
Press ReleaseSOURCE: Joslin Diabetes Center
Two Studies Suggest Link Between Insulin Signaling and Diabetes, Appetite, Obesity and Infertility
BOSTON, Sept. 21 /PRNewswire/ -- Two research studies being released this week by scientists at Joslin Diabetes Center and their colleagues suggest two locations in the insulin signaling system that may result in type 2 diabetes and several conditions frequently associated with this form of diabetes, namely the inability to control appetite, obesity and even infertility.
One paper, being published tomorrow in the journal Science, suggests that when the insulin receptor in the brain is shut off through genetic alterations, the mice also develop type 2 diabetes, their appetites are increased, they gain weight, and their reproductive capabilities decline.
The other paper, being published today in the journal Nature, suggests that when IRS-2 -- a protein inside cells and involved in the insulin signaling process -- is shut off through genetic alterations, the mice develop type 2 diabetes, their appetites increase, they gain weight and their reproductive capabilities decline.
Together these papers demonstrate a previously unappreciated role of the brain in control of metabolism and of insulin in control of reproduction. Although many scientists have long thought that insulin was largely inactive in the brain, more recent studies have begun to unravel this hypothesis. In both papers, this decline in reproductive abilities and increased weight gain and appetite occur in a much more pronounced way in the female mice than in the male mice. The insulin receptor plays a role in insulin signaling in all tissues, where as the effects of IRS-2 are most important in the liver, beta cells of the pancreas and brain.
Authors of the Nature study include: Morris F. White, Ph.D., of Joslin and the Howard Hughes Medical Institute; Deborah J. Burks, Ph.D., Martin G. Myers, M.D., of Joslin; Jaime Font de Mora of Dana-Farber Cancer Institute in Boston; Dominic J. Withers of Imperial College School of Medicine in London; Markus Schubert of the University of Cologne, Germany; Heather H. Towery, Shari L. Altamuro and Carrie L. Flint.
Authors of the Science study include: C. Ronald Kahn, M.D., and Deborah J. Burks, Ph.D., of Joslin; Jens C. Bruning, Dinesh Gautam, Jennifer Gillette, Markus Schubert, Wilhelm Krone, and Dirk Muller-Wieland of the University of Cologne, Germany; Paul C. Orban and Rudiger Klein of the European Molecular Biology Laboratory in Heidelberg, Germany.
To request news releases or interviews, contact Marge Dwyer, Joslin Communications, at 617/ 732-2415 or by email at Marjorie.Dwyer@joslin.harvard.edu. The releases are posted on Joslin's Web site at http://www.joslin.org/.
SOURCE: Joslin Diabetes Center