DNA regulation drives aging but is not the only engine

Scientists have spent decades trying to understand what drives aging. Is it damaged mitochondria? Shortened telomeres? Cells that have stopped dividing and release harmful signals? The answer is likely: all of the above, but not in equal measure. The researchers introduce the Polycentric Aging Framework (PAF), which describes aging as the interplay of partly independent centres, each with its own pace and contribution.

Epigenetic change as the central driver

The framework places epigenetic change at the top. Epigenetics refers to the processes that determine which genes are active, without the DNA sequence itself changing. With age, these processes become disrupted: genes that should be silent become active, and vice versa. The researchers argue that this is the most influential, though not the only, life-limiting factor.

Biological aging clocks, methods that estimate how old a cell is biologically based on DNA markers, are useful but incomplete. They measure a mixture of harmful changes and adaptations the body itself makes to compensate for damage. Both look the same in measurements. That makes interpretation difficult: a clock reading older does not always mean faster aging.

Implications for therapies

The framework predicts that therapies will only work if they target the centre that is currently limiting for a given tissue and life stage. What works for a seventy-year-old with heart problems need not work for a fifty-year-old with cognitive complaints. And if one centre is resolved, another takes over the limiting role.

This is a theoretical article, based on integrating existing research. The framework makes predictions that can be tested, but is not itself experimental evidence. It does offer a structured way to organise existing findings and formulate new research questions.

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