Everyone gets older, and everyone ages. But there’s a difference between simply getting older and aging.
When it comes to getting old, we’re all on the same boat — every 365 days, we just add one more year to our age. When it comes to aging, though, there are those who age ‘gracefully’, so to speak, and there are those who age horribly. And that’s because the way we age is affected by a host of different factors including genetics, diet, lifestyle and our environment.
To better understand how each of the contributory factors affect aging — specifically which accelerates it and what can slow it down — researchers refer to an age biomarker known as the epigenetic clock. In contrast with a traditional clock which measures chronological time and age, an epigenetic clock is much more subjective in the sense that it measures biological age or how well your body functions compared to your chronological age. It’s basically the reference used to declare that a 25-year old person, for example, has skin that belongs to a 40-year old.
The big question is: how does this epigenetic clock actually work? And going further, is there a way to alter how fast or how slow it ticks?
According to a research team at the Babraham Institute and the European Bioinformatics Institute, they have identified a mouse epigenetic aging clock that can predict mouse age with an accuracy of +/- 3.3 weeks. It’s considered a revolutionary find because its accuracy rate is almost similar to the results derived from DNA methylation, a process that can be used to determine chronological age in humans using any bodily tissue or fluid, and one that results in an accuracy rate of +/- 3.6 years, and which can also be used to determine a person’s biological age.
Using their mouse model, the team was able to show that behaviors known to reduce life span made the clock tick faster. For instance, having a high fat diet is accepted as an unhealthy way to live. Unsurprisingly, such kind of diet was shown to speed up the epigenetic clock. And the team was able to detect this effect in as early as 9 weeks.
The team says that their discovery is an exciting one because ‘it suggests that this epigenetic clock may be a fundamental and conserved feature of mammalian ageing.’ And by doing an in-depth study on how the mouse epigenetic ageing clock works, valuable insights on the aging process can be gained.
Professor Wolf Reik, Head of the Epigenetics Programme at the Babraham Institute, noted that it is “fascinating to imagine how such a clock could be built from molecular components we know a lot about (the DNA methylation machinery). We can then make subtle changes in these components and see if our mice live shorter, or more interestingly, longer.” Such studies may provide deeper mechanistic insights into the ageing process and whether lifespan in a species is in some way programmed”.
More importantly, this may serve as the basis for initiating changes or adjustments that can be done in humans to improve health and even extend life expectancy.
The results of the study have recently been published in Genome Biology under the title “Multi-tissue DNA methylation age predictor in mouse”.