Cell: Young microbes and old microbes work together to extend their lifespan

Scientists at the Francis Crick Institute have found that when young and old cells cooperate and exchange resources, all cells live longer
.

Cells produce energy through a complex network of chemical processes that together make up the cell's metabolism
.
While a cell's metabolism is critical to its own survival, it can also affect neighboring cells
.

In their study, published today in the journal Cell, the team looked at how chemical reactions occurring within yeast cells affect the lifespan
of a broader cell community.
They focused on the processes that cells use to exchange metabolites, which are substances
produced when cells produce energy.

Using state-of-the-art techniques to track the path of metabolite exchange, they found that young cells grow and divide frequently, releasing amino acids into the environment, and when these amino acids are taken up by older cells, the entire cell community lives longer
.

One of the amino acids, methionine, is particularly important
.
Methionine is a sulfur-containing amino acid found in all living things, including humans, necessary to initiate the protein-building process, and important in
many cellular processes.

The researchers found that consuming methionine altered the metabolism of senescent cells, affecting key anti-aging pathways, such as those that affect antioxidants
.
It also leads to the release of metabolites with protective properties into the environment, which can then be absorbed
by other cells.
These include glycerin, which is necessary for building cell membranes
.

"Metabolism is a key factor influencing aging, and metabolism occurs not only inside cells, but also between cells," explains Markus Ralser, senior author and group leader of molecular biology at the Crick Metabolic Laboratory and head
of the Charité Institute for Biochemistry, a leading university hospital in Berlin.
"When cells take up methionine instead of producing it internally, this leads to fundamental changes
within the cell.
These changes benefit not only individual cells, but entire communities
.
We have previously demonstrated that there are other benefits to cell-friendly behavior, such as increased tolerance to drugs, but this is the first time it has been linked
to longer lifespan.
”

Crick's first author and researcher Clara Correia-Melo, who soon began her own lab at the Leibniz Institute on Aging in Jena, Germany, the Fritz Lipmann Institute (FLI), said: "The study of cellular metabolism has historically focused on what happens inside cells, where hundreds of chemical reactions take place, produce many metabolites and affect the environment
inside cells.
But that's only part of the puzzle, and it's also important to understand how what's
happening inside a cell affects its neighbors.
Our findings suggest that the exchange of metabolites between cells leads to longer lifespans, which may prompt other scientists to explore the role of
metabolism in health and disease by expanding their analysis to include the metabolic environment in cell communities.
" ”

The researchers will continue this work to further investigate in detail the molecular pathways
that work.
They also hope to extend the work to other, more complex organisms, including mammals
.