Scientists believe they have stumbled closer to a biological ‘fountain of youth’.
They have identified 30 genes linked to physical ageing, one of which they say could possibly be modified to extend the lifespan of humans.
Researchers analysed 40,000 genes in their search for clues to longevity.
Scientists from ETH Zurich in Switzerland and the Jena University Hospital in Germany analyzed 40,000 genes from three different organisms: the nematode caenorhabditis elegans, zebra fish and mice.
The scientists were searching for genes that regulated in an identical manner in all three organisms in each stage of again: young, mature and old.
Scientists took samples and measurements of the RNA molecules found in the cells of each animal, which are used, alongside DNA, to direct protein synthesis.
They then created statistical models to establish an intersection of genes that were regulated in the same manner in the worms, fish and mice.
This showed that the three organisms have only 30 genes in common that significantly influence the ageing process.
The team was able to pinpoint the ageing process in the nematodes by selectively blocking RNA of the corresponding genes.
Blocking them extended the lifespan by at least five percent.
One of these genes proved to be particularly influential: the bcat-1 gene.
‘When we blocked the effect of this gene, it significantly extended the mean lifespan of the nematode by up to 25 percent,’ said Michael Ristow, coordinating author of the recently published study and Professor of Energy Metabolism at ETH Zurich.
The researchers were also able to explain how this gene works: the bcat-1 gene carries the code for the enzyme of the same name.
Naturally occurring in food protein building blocks, these include the amino acids L-leucine, L-isoleucine and L-valine.
When the scientists inhibited the gene activity of bcat-1, the branched-chain amino acids accumulated in the tissue, triggering a molecular signalling cascade that increased longevity in the nematodes.
Moreover, the time span during which the worms remained healthy was extended.
As a measure of vitality, the researchers measured the accumulation of ageing pigments, the speed at which the creatures moved, and how often the nematodes successfully reproduced.
All of these parameters improved when the scientists inhibited the activity of the bcat-1 gene.
The scientists also achieved a life-extending effect when they mixed the three branched-chain amino acids into the nematodes’ food.
However, the effect was generally less pronounced because the bcat-1 gene was still active, which meant that the amino acids continued to be degraded and their life-extending effects could not develop as effectively.
Ristow believes this mechanism also occurs in humans.
‘We looked only for the genes that are conserved in evolution and therefore exist in all organisms, including humans,’ he said.
Ristow also stated that the multiple branched-chain amino acids are currently being used to treat liver damage and can be found in sport nutrition products.
This study aims to deliver important indicators on how the ageing process can be influenced and how age-related diseases like diabetes or high blood pressure could be prevented.
With prevented measures, the elderly can improve the quality of their life all while cutting their healthcare costs.