A new Joslin Diabetes Center-led study has identified a protein found in fat cells that may play a major role in how fat is produced and stored, offering a new target for treatments to prevent obesity and reduce the risk for type 2 diabetes.
This latest research appears in the August 2007 issue of Cell Metabolism.
The study examined the role of a protein called Sirt2, a member of the sirtuin family of seven cellular proteins. These proteins have recently been shown to be important in the control of aging and metabolism. Previous studies have focused on one member of this family, Sirt1, which is activated by high doses of resveratrol, a substance found in red grapes, which can prevent diabetes from developing and also prolong life. This finding generated tremendous attention, leading biotechnology and pharmaceutical companies to begin developing drugs and supplements to harness this effect. Joslin researchers have focused on other sirtuin proteins to find out what role they might play in fat and glucose metabolism and fat development.
This led to the discovery that Sirt2 is the most abundant of the sirtuins in fat cells, expressed in quantities five to ten times higher than other sirtuin proteins. "We wanted to find out what would happen to the behavior of fat cells--in terms of metabolism or growth--if we changed the levels of Sirt2," said lead investigator C. Ronald Kahn, M.D., an internationally recognized researcher who is head of the Joslin section on Obesity and Hormone Action and the Mary K. Iacocca Professor of Medicine at Harvard Medical School.
When a person gains weight, cells in connective tissue known as pre-adipocytes differentiate and fill with fat and form adipocytes, which are able to store fat as a potential energy source when food is not available. However, too much fat storage leads to obesity and obesity-related diseases, including type 2 diabetes.