Aging clocks offer insights into biological versus chronological age differences

Scientists at the University of Cologne's CECAD, the Cluster of Excellence Cellular Stress Responses in Aging-Associated Diseases, have unveiled significant findings about the operation of aging clocks. These devices measure biological age-which can vary due to environmental factors like smoking or diet-more accurately than chronological age, determined merely by date of birth. The research led by David Meyer and Professor Dr Bjorn Schumacher revealed that aging clocks primarily track the accumulation of stochastic changes in cells. Their study, "Aging clocks based on accumulating stochastic variation," has been published in Nature Aging.

"Aging is triggered when the building blocks in our cells become damaged. Where this damage occurs is for the most part random. Our work combines the accuracy of aging clocks with the accumulation of entirely stochastic changes in our cells," said Professor Schumacher.

As people age, their cellular control mechanisms degrade, leading to more stochastic outcomes, particularly noticeable in DNA methylation changes. Methylation, crucial for regulating DNA, undergoes random alterations over time, making it a reliable aging indicator. Both Meyer and Schumacher expanded this concept, suggesting that stochastic variations in any cellular process could potentially predict age.

They further investigated the impact of lifestyle on these biological clocks. Their findings indicate that smoking amplifies random cellular changes, while caloric restriction in mice reduces these variations, potentially slowing aging. Remarkably, they also demonstrated that this stochastic noise is reversible by reprogramming adult cells back to stem cells, effectively rejuvenating them.

Meyer and Schumacher are optimistic that understanding and manipulating these stochastic processes could lead to new anti-aging strategies, potentially achieving cellular rejuvenation. The focus might include repairing DNA changes or enhancing gene expression control.

Research Report:Aging clocks based on accumulating stochastic variation