A common diabetes medicine, called metformin, extends healthy lifespan.
There have been previous hints that metformin could suppress the development of certain cancers and cardiovascular conditions. Recent findings in worms (more specifically, Caenorhabditis elegans, one of the workhorses in aging research and general molecular biology) and mice have further shown that this drug also slows down the aging process.
But how? That was a mystery. Until a new study, performed by researchers from the KU Leuven and the University of Ghent, and published in the Proceedings of the National Academy of Sciences, elucidated a surprising mechanism that underlies the age-fighting effects of the diabetes medicine.
It’s All About Oxygen
The main players, it seems, are oxygen particles. More specifically, as the mitochondria, the energy plants of the cells, do their work, unwanted oxygen tends to get produced. This oxygen can damage proteins and DNA. So, that doesn’t sound like a good thing.
However, what the authors, led by Wouter De Haes, found was that metformin actually increased the production of these supposedly harmful oxygen particles. Bet you didn’t see that one coming. But how can this be: more ‘bad’ oxygen means better health and a longer life?
As with many other things, it seems that moderation is key. De Haes and colleagues found that when a small amount of these oxygen particles is released, these bad boys are captured before they can do any real harm. And what’s more, in doing so, the cells actually become stronger.
The Antioxidant Paradox.
But wait, what about the whole fuss about antioxidants? Indeed, as reactive oxygen species tend to damage DNA and proteins, they’re often appointed as major culprits in the complex biological process that is aging. Thus, the reasoning goes, throw in some anitoxidants to fight these biological villains. The story, however, is much more complicated. In fact, adding antioxidants decreased the life-lengthening effects of metformin.
So, antioxidants are bad then? Not exactly, you can still enjoy your glass of red wine or piece of dark chocolate. Balance is everything. Antioxidants are still useful to take care of an overload of damage-inducing oxygen particles, released, for example, in situations of stress. But low concentrations of these oxygen molecules can trigger cellular defense mechanisms which could lead to stronger, healthier cells.
A bit of Nietzsche (“That which does not kill us, makes us stronger”) at cellular scale.
De Haes W, Frooninckx L, Van Assche R, Smolders A, Depuydt G, Billen J, Braeckman BP, Schoofs L, & Temmerman L (2014). Metformin promotes lifespan through mitohormesis via the peroxiredoxin PRDX-2. Proceedings of the National Academy of Sciences of the United States of America PMID: 24889636
lifespan, diabetes, metformin, medicine, ageing, anti-ageing, antioxidants, oxygen