BOSTON — An enzyme found in the mitochondria of cells decreased in the skeletal muscle of those with Type 2 diabetes, according to researchers at the Joslin Diabetes Center.
The study sought to understand how decreased levels of enzyme Sirt3 might influence the metabolism of cells, particularly how it could affect insulin action in cells. According to the study, Sirt3 levels in the skeletal muscle of those with Type 2 diabetes decreases by at least 50%, compared with those without Type 2 diabetes, researchers said. This may indicate why insulin resistance develops, which is one of the indicators of Type 2 diabetes.
“Ours is perhaps the first study to understand what is going wrong in the mitochondria of those with diabetes,” said senior author C. Ronald Kahn, head of the Joslin section on integrative physiology and metabolism and the Mary K. Iacocca professor of medicine at Harvard Medical School. “Many studies have shown that the mitochondria don’t work well in those with diabetes. This points to a cause of why they don’t work well.”
The mitochondria of cells, known as the "powerhouse," converts energy into usable forms. Kahn said the study showed that when Sirt3 levels are low, as they are in the case of diabetes, the mitochondria of the cells are not as efficient in energy metabolism as they should be. The study also indicated that drug makers may want to develop drugs that boost Sirt3 enzyme levels, which potentially could help fight the disease.
“Agents which increase Sirt3 activity could, therefore, potentially reverse at least some of the adverse effects of Type 2 diabetes,” the researchers wrote in the paper, which was published online in the Proceedings of the National Academy of Sciences.