Using a mouse model, researchers at the University of North Carolina have reported that a fat hormone which causes changes in the metabolism may increase life span.
Terry Combs and colleagues demonstrated that long-lived Snell dwarf mice burn less glucose and more fatty acids during periods of fasting, and as a result produce fewer free radicals.
The key to this switch may be adiponectin, a hormone produced by fat cells that helps lower glucose production and stimulates cells to use fat for energy instead.
Researchers discovered that Snell mice had three times as much adiponectin in their blood as control mice; Snell mice also had fewer triglycerides in their cells, indicative of higher fat metabolism.
The advantage of burning fats instead of glucose for energy is that it produces fewer oxygen radicals, which can damage cells and exacerbate the effects of aging.
Confirming this, researchers found far less free radical damage, measured as the frequency of a chemical modification on protein known as carbonyl groups, in Snell mice than controls.