NEW YORK (GenomeWeb) — Researchers at ETH Zurich and the JenAge consortium have identified genes associated with the aging process.
As they reported in Nature Communications this week, the researchers combed through 40,000 genes in the genomes of C. elegans, zebra fish, and mice to determine which ones were regulated identically in all three organisms in each stage of aging — youth, maturity, and old age. They found 30 genes that were upregulated or downregulated the same way in all three organisms to significantly influenced aging. And by blocking the expression of each gene, they found approximately a dozen that extended the lifespan of C. elegans by at least 5 percent. One particular gene — bcat-1 — proved particularly interesting. Blocking its activity extended the mean lifespan of C. elegans by up to 25 percent.
Impairing bcat-1 led to excessive levels of branched chain amino acids (BCAAs) like L-leucine, L-isoleucine, and L-valine, the team wrote. They also showed that BCAAs reduce a LET-363/mTOR-dependent neuro-endocrine signal, identified as DAF-7/TGFβ, all of which had an impact on lifespan.
Further, feeding the C. elegans foods rich in BCAAs extended their lifespan, a finding consistent with previous studies of mice. "Taken together, BCAAs act as periphery-derived metabokines that induce a central neuro-endocrine response, culminating in extended healthspan," the researchers wrote.
ETH Zurich professor and coordinating author Michael Ristow believes his team's findings can be applied to humans. "We looked only for the genes that are conserved in evolution and therefore exist in all organisms, including humans," he said in a statement.
His team is planning a follow-up study, and while they cannot accurately measure the life expectancy of humans, they plan to study health indicators like the cholesterol and blood sugar levels of the study participants.
"The point is not for people to grow even older, but rather to stay healthy for longer," he said, adding that these findings could present researchers with new ways to study, mitigate, or prevent age-related illnesses like diabetes and high blood pressure. Such measures could also cut healthcare costs.