Researchers from Massachusetts Institute of Technology found that sirtuins (SIRT1) help fight off disorders linked to obesity.
When put on a high-fat diet, mice lacking the protein started to develop metabolic disorders, such as diabetes, much sooner than normal mice given a high-fat diet.
"We see them as being poised for metabolic dysfunction," says Guarente, MIT biology professor Leonard Guarente said.
"You've removed one of the safeguards against metabolic decline, so if you now give them the trigger of a high-fat diet, they're much more sensitive than the normal mouse," Guarente said in a statement.
The finding raises the possibility that drugs that enhance SIRT1 activity may help protect against obesity-linked diseases.
SIRT1 is a protein that removes acetyl groups from other proteins, modifying their activity. The possible targets of this deacetylation are numerous, which is likely what gives SIRT1 its broad range of protective powers, Guarente said.
The researchers found that in normal mice given a high-fat diet, the SIRT1 protein is cleaved by an enzyme called caspase-1, which is induced by inflammation.
It's already known that high-fat diets can provoke inflammation, though it's unclear exactly how that happens, Guarente said.
"What our study says is that once you induce the inflammatory response, the consequence in the fat cells is that SIRT1 will be cleaved," he said.
The study was published in the journal Cell Metabolism.
