Naked mole rats live up to nine times longer than other similarly sized rodents and are to all appearances immune to cancer. These facts make the species of considerable interest to researchers who study aging: what exactly are the biological mechanisms by which this longevity is achieved? So far it seems that naked mole rats are very resistant to the consequences of high levels of oxidative damage to molecular machinery within cells, and they have exceptionally good maintenance of proteostasis, the ability to keep protein levels stable over time and avoid the buildup of amyloids made up of misfolded proteins. But there is still much to be determined of the mechanisms by which these attributes are managed.
Here is a recent report from researchers involved in these investigations, focusing on cellular quality control mechanisms:
A new study links the naked mole rat's remarkable lifespan to a molecular chaperone protein known as heat shock protein 25 (HSP25). HSP25 and other chaperone proteins act like a tiny quality-control team within an animal's cells, quickly eliminating incorrectly manufactured or damaged proteins before they can cause a problem. Researchers say understanding changes in the actions of HSP25 during aging could shed light on age-related diseases like Alzheimer's and Parkinson's.
The researchers compared HSP25 levels in naked mole rats to levels of the protein found in rodents with different maximum lifespans, from mice (four years) to guinea pigs (12 years) to Damaraland mole rats (20 years) and others in between.
"Using a variety of rodents, we found that the amount of HSP25 present in their tissues positively correlated with the animal's maximum lifespan. If we can understand how HSP25 levels are regulated, what its function is and how it contributes to cell health, we might find ways to use this protein to combat devastating age-related diseases. In animals with higher levels of HSP25, having more of these quality-control proteins means they are primed to react when there is a problem, so they can quickly transport the faulty protein to cellular garbage dumps and maintain the health of the cell."