Live Long and Prosper: Can Exercise Make You Immortal?

Live Long and Prosper: Can Exercise Make You Immortal?

Italian scientists have discovered that exercise could lengthen our lifespan - but not in the way most people expect. Research on diabetic patients has uncovered that exercise can reduce oxidative stress and lengthen a chromosome's telomeres. As researchers continue to study genomic stability, DNA repair, and longevity, is immortality a possibility?

Written By: Micaela Leong

It is common knowledge that exercise brings great benefits to our lives and overall well-being. Aerobic exercise improves your stamina and metabolism, strengthens muscles, and prevents weight-related diseases, such as diabetes, high blood pressure, or heart disease. With a healthy body and lifestyle, it is possible to live life for as long as possible. However, researchers from Italy studying diabetics patients discovered that it can change your genome as well.

Experiments were conducted on diabetic patients and healthy subjects, to see whether exercise had an effect on their DNA structure and expression. They observed that exercising can lengthen telomeres, allow cells to withstand oxidative DNA damage, and promote genes that either repair DNA or prevent oxidative stress.

Among those in the control group who did not receive exercise, the healthy subjects had longer telomeres than diabetic subjects, meaning that a healthy person's cells are able to survive longer than a diabetic's. However, all subjects who were allowed to exercise, displayed longer telomeres than the control group - with little difference between exercising diabetics and normal subjects.

The scientists also put all participants under oxidative stress, to see how exercise affected the amount of damaged DNA. Diabetics without exercise had the most, whereas exercising diabetics had the same amount of damage as healthy people in both exercising and non-exercising groups.

If exercise can lengthen telomeres and reduce the amount of DNA damaged by oxidative stress, how could it possibly extend our lives?

The Art of Aging Gracefully

Aging is not just about growing old or how long you have lived for, it is about how functional the body is. As time progresses, the body wears out, like a well-used pair of shoes. Our cells eventually lose their ability to work, making the body more susceptible to diseases and illnesses.

When cells age, they progressively lose their cellular functions and become more susceptible to stress. During this, they undergo senescence when they can finally no longer divide. Like a game character on its last life: there is no chance to live again. This happens either when its DNA is damaged by high levels of oxidative stress (cellular senescence), or when telomeres are completely gone (replicative senescence).

Oxidative stress is when there is an imbalance between free radicals and antioxidants. Usually, free radicals, which are oxygen-containing molecules with an unpaired electron, need to find an electron from another molecule to stabilise. The body can combat this with antioxidants, which can donate its own unpaired electrons to them. However, when there are not enough antioxidants, free radicals steal electrons from DNA instead, destabilising it. In the case of diabetes, several abnormalities, such as hyperglycemia and insulin resistance, enhances susceptibility to oxidative stress. This is also why in the experiment with induced oxidative stress, the diabetic patients without exercise had the most DNA damage.

Telomeres play an important role in the livelihood of a cell. They act like the plastic tips of a shoelace. Over time, the coating wears off and you are left with frayed laces. Without the tips, it is increasingly difficult to thread your laces onto your shoes again. Similarly, the telomeres shorten with every cell division, and once it is gone, the cell can never replicate again. Even though the degradation occurs naturally, it can be accelerated by oxidative stress, if the telomeres are attacked by free radicals.

It then makes sense that if the DNA or telomeres are damaged, cells are more likely to senesce and die earlier than expected. If exercise is able to reduce DNA damage and reverse telomere shortening, thus delaying cellular or telomeric senescence, is it possible to live forever?

My (Cancerous) Immortal

One of the reasons why cancer is notoriously difficult to get rid of, is because it is immortal. Cancer cells have a special enzyme called telomerase, that maintains the telomeres by constantly extending it every cell division. If it cannot senesce, it just continuously replicates, producing more of itself, and eventually creates a tumour, which is an overgrowth of tissue. Human cells can also synthesise telomerase, however, most of them are inactive. Scientists are studying what happens if activated telomerase was introduced in healthy, adult cells.

Even so, that only solves telomeric senescence. Cancer cells are an amalgamation of genetic mutations, some of which are on the gene for apoptosis, the cell’s “self-destruct” function. When the gene is dysfunctional, it cannot be read, so the cancer cell may never kill itself. If we seek immortality, it is tempting to switch off our “kill switch” too - but apoptosis is encoded for a reason. Without apoptosis, a mutated, dangerous cell could go rogue and damage the surrounding tissue and wreak havoc. Even worse, if it becomes cancerous, the body would have a hard time keeping everything under control.

With Great Power Comes Great Responsibility

As scientists continue to study genomic stability and telomeres, in an effort to understand the life and death of cells, immortality will always be at the back of people’s minds. However, tampering with the genetic code to attain it, proves to be dangerous and uncharted territory. At least there is a safer, healthier way to maintain the life we have, especially now that we know that exercise can lengthen telomeres and prevent damage to DNA. Sometimes, what matters more is preserving what we have now, rather than trying to live forever.

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Reference:

Dimauro, I., Sgura, A., Pittaluga, M., Magi, F., Fantini, C., Mancinelli, R., . . . Caporossi, D. (2017, June 23). Regular exercise participation improves genomic stability in diabetic patients: an exploratory study to analyse telomere length and DNA damage. Retrieved July 21, 2017, from https://www.nature.com/articles/s41598-017-04448-4

What is a Telomere? | Human Cellular Aging | T.A. Sciences TA-65. (n.d.). Retrieved July 21, 2017, from https://www.tasciences.com/what-is-a-telomere/

Clark, J. (2009, May 11). Will the Hayflick limit keep us from living forever? Retrieved July 21, 2017, from http://science.howstuffworks.com/life/genetic/hayflick-limit2.htm

Mandal, M. D. (2015, September 10). What is Oxidative Stress? Retrieved July 21, 2017, from http://www.news-medical.net/health/What-is-Oxidative-Stress.aspx