Researchers identify enzyme that holds key to living longer through calorie restriction
By Darren Quick
November 2, 2011
Studies have shown that restricting the intake of calories without reducing the intake of vitamins and minerals slows the signs of aging in a wide range of animals including monkeys, rats and fish, and even some fungi. More recent studies provide evidence that calorie restriction can also have the same effect on humans and now researchers at the University of Gothenburg have identified one of the enzymes they claim plays a major role in the aging process.
Although calorie restriction has been shown to slow the aging process, delay the development of age-related diseases and have favorable effects on health, researchers have had a hard time explaining why this is so. Using yeast as a model, researchers at the University of Gothenburg have successfully identified that active peroxiredoxin 1 (Prx1), an enzyme that breaks down harmful hydrogen peroxide in the cells, is required for caloric restriction to work effectively.
The research team's study showed that Prx1 is damaged during aging and loses its activity but caloric restriction counteracts this by increasing the production of another enzyme called Srx1, which repairs Prx1. In potentially good news for those that like their food, the team also found that aging can be delayed without caloric restriction by increasing the quantity of Srx1 in the cell.
"Impaired Prx1 function leads to various types of genetic defects and cancer. Conversely, we can now speculate whether increased repair of Prx1 during aging can counteract, or at least delay, the development of cancer," said Mikael Molin of the University of Gothenburg's Department of Cell and Molecular Biology.
The researchers say that it has also been shown that peroxiredoxins are capable of preventing proteins from being damaged and aggregating, a process that has been linked to several age-related disorders affecting the nervous system, such as Alzheimer's and Parkinson's. Therefore, they are also considering whether stimulation of Prx1 can reduce and delay such disease processes.
The University of Gothenburg team's study, Life Span Extension and H2O2 Resistance Elicited by Caloric Restriction Require the Peroxiredoxin Tsa1 in Saccharomyces cerevisiae has been published in the journal Molecular Cell.