A telomere is defined as the specialized repetitive DNA sequence at the end of the linear chromosome, and associated proteins, that serve to maintain the integrity of the chromosome(Shay and Wright, 2007). In simple terms a telomere is like the plastic end of a shoelace which helps protect the shoelace from becoming frayed. Telomeres are not genes, but they are needed for the proper duplication of the chromosomes in dividing cells(Panno, 2011). Telomerase is the enzyme which helps prevent the telomere from shortening. Without telomerase the telomere will shorten and limit the growth of the cell until the cell enters a state called senescence. When the cell is in a state of senescence it will no longer divide and this can lead to disease and advanced aging. Senescent cells can leak proinflammatory substances that make you vulnerable to more pain and more chronic illness(Blackburn and Epel, 2017). So the question is how can we preserve our telomeres and slow down the aging process and the development of disease.
1. What is the cause of telomere shortening?
Each time chromosomes are duplicated, the telomeres shrink until they are so short the DNA replication machinery can no longer work(Panno, 2011). The cell has then reached the state of senescence. Some people are born with an inherited form of telomere biology disorders which leads to many health disorders and a shortened lifespan. This disorder is very rare and affects about one in a million people. Several observational studies have attempted to gain insight into the question of whether age-related telomere shortening in human peripheral white blood cells is associated with health and disease status(Hornsby, 2007). One study showed that socioeconomic status can have an impact on white blood cell telomere dynamics (Cherkas,2006). Another study showed chronic stress is thought to be a culprit for telomere shortening. A study completed by Dr. Elizabeth Blackburn and Dr. Elissa Epel looked at highly stressed caregivers. These caregivers were mothers taking care of chronically ill children (Blackburn and Epel, 2017). It was found that the longer a mother took care of her special needs child the shorter her telomeres. It was found that highly stressed mothers of healthy children also had shorter telomeres. The highly stressed caregivers demonstrated lower vagus activity during stress and higher stress hormones while sleeping (Blackburn and Epel,2017). Not all psychological stress will cause shortening of telomeres but stress that affects the endocrine system can cause a difference in telomere length. The possible difference in telomere length in individuals of differing psychological status lies in the actions of hormones such as glucocorticoids on cell death and cell proliferation in the hematopoietic system (Hornsby,2007). Chronic stress that lasts a long time is very toxic and it’s very important to try and decrease the psychological stress. People under a great deal of stress often look run down and older than their chronological age. They may also show evidence of disease. Some other factors that can shorten telomeres are increased belly fat, sedentary lifestyle and age.
2. What role does telomerase play in the lengthening of telomeres?
As was briefly discussed in the abstract telomerase is an enzyme which works in your stem cells to regrow your telomeres (Park,2018). Telomerase can help preserve the telomeres and protect your DNA. In simple terms telomerase can help restore the telomere after each cell division. This can help you resist the aging process and disease. Normal healthy people inherit two copies of nearly all genes from their mother and father. There is a disorder called progeria in which the person only has one of two functioning telomerase genes. This disease causes accelerated aging resulting in teenagers dying from old age. Since most of us have two copies of telomerase we can hope to live into our 80’s or longer. Since the discovery of the telomerase enzyme and its role in preserving telomeres there have been ads for telomerase-boosting supplements all over the internet. Actually using artificial methods to increase your telomerase can make you sick. If you are taking a telomerase boosting supplement you can get too much of it into the wrong cells. It can fuel a cancer cell to divide even more rapidly which in turn can cause you to end up with a diagnosis of cancer. The only way to increase your telomerase is through natural methods. Knowing that too much telomerase fuels cancer cells and roughly 80 to 90 percent of malignant human cancers have levels turned up ten to hundreds of times as normal cells is actually an important discovery. Perhaps cancer can be treated by turning off telomerase in cancer cells (Blackburn and Epel, 2017). so we need a healthy amount of telomerase for healthy telomeres to prevent cancer but too much can possibly cause cancer.
3. What disease can be caused by shortened telomeres
There are three stages of development that all animals pass through. These stages include embryogenesis, growth and development and senescence (Panno,2011). The last stage is usually thought of as the aging process. First of all shortened telomeres increase the aging process. You may see age spots, grey hair or a stooped posture from bone loss. These changes happen to all of us but people with shorter telomeres will show these signs sooner. Researchers asked specially trained “raters” to estimate the age of a person just by looking at a photo. It turns out the people who look older have shorter telomeres (Blackburn and Epel,2017). It has been observed that inflammation increases with age. Scientists have given it the name inflamm-aging which is the persistent, low grade inflammation that can accumulate with age (Blackburn and Epel, 2017). Telomere damage is a common reason for inflamm-aging. It’s important to note that one senescent cell can send signals to other cells promoting inflammation.
Quite often when you go to the doctor, especially when you are over forty, many of your symptoms such as fatigue, weight gain, aches and pains, high cholesterol, problems with sleep, high blood pressure and digestive issues are seen as ordinary and part of the aging process. You will probably be given prescriptions and told to modify your diet and exercise but the provider usually doesn’t know what diet is the right one for you. Any consideration of addressing a common cause (the shortening of telomeres) and a single remedy (the preservation of telomeres) causing these signs and symptoms will never be discussed (Park,2018). The shortening of telomeres can cause a thousand diseases.
Some diseases linked to shortened telomeres include heart disease, lung diseases, cognitive slowing, Alzheimer’s disease, diegstive disorders, and arthritis. Atherosclerosis is the most common form of disease of the arteries. This is caused by an excess of low density lipoprotein in the blood which leads to the buildup of fatty deposits in the arteries. Heart disease is linked to low telomerase activity. The University of California-San Francisco researchers did urine and blood tests to determine the health markers and telomerase activity of 62 women ages 35 to 41 who were at high risk for heart disease. They also had the women report their mental stress. Based on their health issues such as high blood sugar, high blood pressure, smoking, elevated stress hormones and high levels of belly fat, the researchers concluded that low telomerase is an early marker of heart disease (Park,2018). It’s also been found that having less belly fat is important to preserving your telomeres. People with asthma,chronic obstructive pulmonary disease and pulmonary fibrosis have shorter telomeres in their immune cells and lung cells than healthy people (Blackburn and Epel, 2017). When telomeres of the lung stem cells and blood vessels of the lungs are lacking the cells become senescent. Alzheimer’s disease is the 5th leading cause of death among the elderly. Women are twice as likely to develop AD than men perhaps because of the sharp decline in estrogen during menopause. AD begins in the basal cerebral cortex and spreads to the hippocampus. It does not affect the cerebellum or the brain stem. Four genes have been identified and associated with the onset of AD; Tau, Sen, App and ApoE. Any defect of these genes can lead to the death of neurons (Panno,2011). The question researchers are trying to answer is if shorter telomeres can predict dementia or AD. A large study in Texas tried to answer this question. Researchers imaged the brains of almost two thousand adults from Dallas County. The study controlled for age as well as smoking, gender and the status of the gene ApoE. They examined the hippocampus which is responsible for emotions and memory. The researchers found that people with shorter telomeres in their white blood cells had a smaller hippocampus than people with longer telomeres. If you want to have good memory it is important to replenish the cells of the hippocampus along with other areas of the brain including the amygdala and the temporal and parietal lobes (Blackburn and Epel,2017). Rheumatoid Arthritis and other joint issues can be caused by shortened telomeres. RA is an autoimmune disease that occurs when the body’s own immune system mistakenly attacks the synovium. Pain, stiffness ,swelling and loss of joint function occur. In a study published in Arthritis Research and Therapy investigators tested the telomere length in DNA cartilage of 14 osteoarthritis patients who were having knee replacements. The telomere length was shorter when compared to nine adults of the same age without arthritis but was even shorter in the cells near the arthritic area (Park,2017). Finally, shortened telomeres can lead to narrowing of the digestive tract.
4. What can we do to keep our telomeres long and help minimize disease?
Many people assume that as you age certain diseases are inevitable especially if there is a genetic component in the family. People often say I used to be able to do something but I can’t now because of joint pain or being too fatigued. They think this is the normal part of aging and needing to be on more and more medication is inevitable. Then there are people who are skiing in their 70’s or running marathons in their 80’s. If we want to keep ourselves free from as many diseases as possible we need to adopt lifestyle changes that lengthen telomeres and allow us to age gracefully. The question is how do we do this? When we discuss what shortens telomeres, stress is one of the main culprits. Looking back on the caregiver study the cells of the caregivers showed significantly lower telomerase in the CD8 cells. Negative thinking was associated with lower telomerase. However there were many caregivers who felt joy and saw their stress as a challenge and not a threat and avoided rumination. These caregivers were shown to have higher telomerase (Blackburn and Epel,2017). To help decrease toxic stress we need to adopt resilient methods. These therapies are based on acceptance and mindfulness. They don’t change your thoughts but help you change your relationship with them. This can be accomplished through a variety of techniques which make you more aware of these negative thoughts and provide clarity. This can be achieved through mind- body exercises such as meditation and yoga. Even long distance running can help accomplish this. Engaging in any kind of mind-body practice regularly allows you to be less focused on negative thoughts about yourself; you get better at noticing your surroundings and other people (Blackburn and Epel,2017). A simple technique to reduce stress is a three minute breathing break. This calms your body and can give you some control over your stressful feelings. Finally, music therapy has been shown to decrease stress, pain and nausea in cancer patients and reduce pain during dental procedures. The therapeutic power of music on stress reduction may help improve our health (Butler, 2010).
Exercise has been found to increase telomerase. Moderate intensity aerobic exercise performed for 45 minutes at a time three times a week or high- intensity interval exercise performed for six months was shown to increase telomerase activity twofold. Resistance training did not show the same effect but is still important. People who engage in at least two out of four different types of exercise showed significantly longer telomeres. The types of exercises include moderate intensity, vigorous intensity, walking/cycling for transportation and muscle strengthening (Park, 2018)
Getting restorative sleep is another way to keep telomeres longer. It’s important to have at least seven hours of sleep per night. Sleep is the most restorative activity a person can perform. Healthy sleep helps to set our internal biological clock, heals memories, helps to decrease cravings for sugary, fatty foods and improves mood. Think of sleep as the mental de-fragmentation and spiritual shaking of the Etch A Sketch (Parks, 2018).
It is thought that an elevated BMI would show a correlation of shortened telomeres but actually metabolic health is of much greater importance. To put it simply it’s the belly and not the BMI. BMI is not a reliable source of health because it does not take into consideration how much muscle to fat ratio a person has or where the majority of fat resides. When we say a person has poor metabolic health we are talking about belly fat, high cholesterol, high blood pressure and insulin resistance. Strict dieting and counting calories may not be the answer since this can be stressful to the mind. Studies have not shown that extreme calorie reduction has led to any improvements in telomeres. Actually patients who underwent bariatric surgery had shorter telomeres one year later. To help improve our metabolic health with lasting effects and not having to severely restrict our calories is through exercise and choosing whole unprocessed foods over sugary packaged foods. All calories are not the same. Limiting sugar consumption may be the single most beneficial change you can make to your diet (Blackburn and Epel, 2017). For many people, knowing that very dark chocolate has shown to slow down the shortening of telomeres because of the polyphenols in chocolate can make adopting a healthful diet more palatable (West, 2012). Some anti-inflammatory foods can help reverse telomere dysfunction. These foods include oily fish, nuts, flax and leafy vegetables. Omega 3 fatty acid supplementation has shown to reduce inflammation and was associated with increased telomere length.(Blackburn and Epel, 2017). Finally, in one study coffee was shown to lengthen telomeres.
Finally we should try and reduce the number of toxins we are exposed to. We want to avoid charring our meat and try to avoid pesticides in our produce. We should consider purchasing organic produce or growing our own vegetables. It’s beneficial to our health to use house cleaning products with natural ingredients and find safe personal care items.
Conclusion
In conclusion the research shows that the length of our telomeres and how much telomerase activity we have can be directly linked to our level of stress and lifestyle. It is inevitable that as we age our telomeres will become somewhat shorter but we don’t want our cells to enter a state of senescence. We also don’t want to increase our telomerase activity with supplements or being exposed to toxins which can also boost our telomerase activity in a negative way and increase our chances of developing cancer. By incorporating measures to decrease our toxic stress, improve our eating habits, exercising and getting enough sleep we can increase the likelihood of aging with less disease and ensuring a better quality of life.
