While it may be a little premature to declare the search for the elixir of youth over, a remarkable milestone in the quest to abolish death and aging may have just been reached. According to a new study in the journal Science, a vitamin called nicotinamide riboside (NR) has the capacity to stimulate the regeneration of lost muscle tissue in elderly mice, while also increasing their lifespan.
Speaking about this apparent breakthrough, lead researcher Johan Auwerx explained that “this work could have very important implications in the field of regenerative medicine,” adding that it may one day be possible to bypass surgery and repair the body with a dietary supplement.
Like all other animals, as we go through life we constantly lose cells through a process called senescence, also known as cell death. However, rather than simply wasting away, our bodies replenish these cells by stimulating stem cells to develop and specialize.
As a consequence of our mortal nature, though, this ability to regenerate slowly decreases over time, resulting in our ultimate demise. Scientists interested in overcoming the finiteness of human life are therefore forever looking for ways to kick-start this process once it begins to slow down, and an international group of researchers may have now solved at least one piece of the puzzle.
According to the team, the key appears to lie in our mitochondria. Often referred to as the “powerhouse” of our cells, these small organelles generate the energy required for a wide variety of cellular processes. The development of stem cells into specialized cells, for instance, relies on energy produced by mitochondria.
Mitochondria are often referred to as the "powerhouses" of cells. RAJ CREATIONZS/Shutterstock
Since mitochondrial dysfunction has been found to be one of the hallmarks of aging, the study authors decided to seek a direct connection between this and the reduced ability of cells to regenerate themselves, in the hope of finding a way to repair this connection.
When stem cells develop, they use up cellular supplies of a compound called nicotinamide adenine dinucleotide (NAD+), which happens to play a vital role in ensuring the healthy functioning of mitochondria. The researchers therefore decided to administer aged mice with NR – which is a precursor of NAD+ – in order to see what effect this would have on their ability to regenerate muscle cells.
Results showed that, after receiving NR, the mice were able to generate larger numbers of muscular stem cells, which later developed into adult muscle cells and translated into enhanced muscular strength and function. For instance, they were soon able to run for longer periods and developed a firmer grip.
The mice that had received NR also lived longer than those that had not been treated with the vitamin – which happens to be very similar to vitamin B3. Significantly, the study authors observed no negative side-effects, even when administering high doses of NR.
Naturally, however, more work is needed before we get too excited about this apparent panacea, as it is not yet known how effectively or safely it can be used to treat aging in humans.