New approach will help find ways to slow down aging more quickly

ARI is a metric that can be measured once, at a specific age, and it immediately indicates whether the animal has entered a state of “slow aging” as a result of the intervention. This differs from conventional assessments of “biological age”; they show how much aging has already accumulated, and to see the dynamics, at least two measurements at different times are needed.

A group of researchers led by Professor Stephen Austad and Richard Miller analyzed data from an intervention testing program supported by the National Institute on Aging of the United States. This program tested various approaches, ranging from medications and diets to mutations of individual genes, and identified 14 agents or combinations that reliably increase the lifespan of mice. Eight of them provided an increase of 12 % or more, and some remained effective even when used later in life.

It turned out that with a wide variety of life‑extension methods — whether medications, calorie restriction, or genetic changes — similar molecular and physiological shifts occur in the mice’s bodies. It is precisely these recurring changes that formed the basis for the 12 proposed candidate ARIs. If these indicators truly reliably distinguish effective interventions from ineffective ones, then experiments on mice can be conducted approximately four times faster and approximately twenty times cheaper.

According to the authors, ARIs will help accelerate the search for anti‑aging agents in three directions at once. First, they will provide a fast and inexpensive way to select promising drugs for further testing on mice. Secondly, it will make it possible to search for medications that cause changes in healthy people similar to those observed in long‑lived mice; this will provide clues about which agents can slow down aging in humans. Thirdly, the ARIs panel will help identify common mechanisms affected by various anti‑aging drugs, and on this basis, select new targets and groups of drugs for development.

Particularly promising is the fact that many effective agents continued to work even when they were started to be used at a later age in mice. Similar therapies could be beneficial for middle‑aged people. Indicators of the rate of aging could become a key tool for transitioning to preventive approaches and for conducting shorter and more realistic clinical trials, which would more quickly lead to the development of new means for healthy longevity.

The proposed candidate markers are not yet ready for use in the clinic. They still need to be tested on different species of mammals and tested in humans. Currently, experts are focused on confirming the reliability of each ARI, finding additional indicators that can be measured in blood plasma, understanding how different interventions affect them, and clarifying their relationship with age‑related diseases — from diabetes and cancer to heart disease and neurodegenerative disorders.

If these indicators can be reliably validated, they will become an important practical bridge between the fundamental biology of aging and trials of interventions aimed at extending healthy life. As Dr. Matt Kieberlein notes, the main challenge is to understand whether intervention affects the rate of aging at all. If a reliable way to answer this question within a reasonable timeframe emerges, it will fundamentally change the possibilities for finding means to extend healthy life expectancy.