On St. Patrick’s Day, hundreds of people gathered at the international Irish pub Whiskey Jake’s, for a panel and Q&A with scientists and experts about aging, arthritis, metabolism and the effects of aging on the body. It wasn’t the usual debate of “The Rock vs. Sly Stallone” — that’s not what we do here.
What we do here is talk about much more serious issues, like exactly what has been discovered over the last year, about what we know about an aging body and what we haven’t. How old does it take to physically die, how quickly can it happen and what is the maximum amount of years we can live the same way? Are there any possibilities for extending life past the point of physical death? For decades, researchers have been trying to answer these questions. The answers that they have found have been profound: age is just one data point among many that track something called a telomere, how healthy cells die and how healthy they are.
The fact that our knowledge of aging is increasing, as is the amount of research scientists are conducting, also has an impact on how we perceive and define “old” and “young” and whether or not there is some consequence for our age beyond walking slowly and getting aches and pains. The average man and woman are aging faster than ever before and yet our perception of aging is not developing the same way. In fact, we still use the same ideas, regarding how old we are, that have been around for generations.
So what is a telomere? Telomeres are not skin cells, like they are usually thought of. They’re really, really long — DNA at the ends of our chromosomes can stretch beyond the original length, down to a point at which they become a bit brittle and then shorten. If we were to try to replace those very short telomeres with new DNA, we would have to start again. The most successful outcome from this will be to treat telomeres as a tumor, instead of simply a mark on chromosomes. That way, a repair process can be triggered and the DNA repair will occur to avoid further unwanted cell death.
Genes affect telomeres in several ways. They may increase or decrease the cell’s ability to repair its genetic code. In essence, the genes of a cell determine how long that cell will live, but a single gene or protein, depending on its particular function, can affect the telomere. Unfortunately, there is no way to tell the difference between a healthy telomere and a defective one.
But epigenetics has opened up a door to this realization and we are seeing telomeres as a potential marker of age. In fact, the findings from a pair of studies published just over the past month are important for understanding how telomeres become shorter over time and how that effect can trigger cell death.
Epigenetics research has begun to shift the way we think about aging. It has led to new ideas and new concepts and has helped us create a more precise sense of who and how old we really are. The results of the studies involving telomeres do lend credence to several theories about how aging occurs.
The first is that being exposed to a stressful event may put a strain on our telomeres. Our genes, as much as anything else, seem to protect us. Being subjected to a stressful event can have a dramatic impact on cells. But what happens when the person being stressed turns the stress on himself? We see cellular death in response to stressful experiences, but this is limited to a few special cells. With the right approach, we may be able to turn stress onto itself and calm its stress-inducing effects. Such treatments have been tested in mice, but in humans the extent of the results is still being tested.
Another theory studies have looked at is the effect of stress on genes that are responsible for the growth of cells, which is akin to what happens during aging. What might happen is that our stress hormones help to promote cell growth and shorten telomeres. But when these aging cells become overly stressed, their survival rate decreases and cells die. This happens in a type of cancer that is related to proteins called tumor necrosis factor activators. The cancer cells cause cells to waste away. Further, telomeres can also influence the ability of cells to survive this process, so stress can help accelerate tumor development.
The studies are helping scientists understand how telomeres may predict the success of existing therapies and how understanding telomeres can help us slow or halt the effects of aging. Another example of this is when someone who was aging at 70
