The end caps on a shoestring:
Imagine pointing an electron microscope at your little finger and enhancing the image until an individual cell in the skin appears. Adjust a little more until you are able to see inside the cell. A number of Duracell batteries (the mitochondria) powers up the cell. The long strings similar to shoelaces indicate the chromosomes (DNA), while the protective plastic tips at the end of the laces, that prevents the shoestring from disintegrating, indicate the telomeres.
Wait till you see movement as the shoestring starts to divide to form a new shoestring. Soon everything in the cell is split in two and two new cells are formed. You’ll notice that the tips of the shoestring are now slightly shorter, and this shortening of the telomeres occurs each time a cell divides. This is significant as you age, as there are dire consequences when the telomeres run out and such cells are now unable to further multiply or offer protection – and the laces start to disintegrate.
The biology behind it:
The tissues in the human body are made of cells that have joined together to perform functions that are specific to the organ where the cells are situated. Each cell is made up of components, with the nucleus being one of them. The nucleus contains structures called chromosomes with all the genetic information and replicating instructions that is passed on from parents to their children. (This genetic information is commonly known as your “genes”.) Each of the two strands (“arms”) of a single chromosome contains a single molecule DNA, which looks like a string of beads, made up of units called bases. A single molecule DNA is about 100 million bases long, while a telomere is about 15 000 bases long at conception in the womb. Cells begin to divide after conception, with telomeres shortening every time the cell divides. By the time your telomeres have been reduced to about 5 000 bases, you basically die of old age.
The spirally chromosomes (“shoelaces”) are strands of DNA that house your genes and is the blueprint to make new, young cells. The body must duplicate cells in order to grow or to repair cells due to aging, and this process is called mitosis. During mitosis each parent cell divides into two new cells, with the original genetic material duplicated. To ensure that the genetic material is passed on correctly to each new cell, the strands of chromosomes (“shoelaces”) have protective caps – called telomeres – at the ends of the strands (“tips of shoelaces”). Telomeres prevent chromosome “strands” from losing base pair sequences at their ends, and also stop chromosomes from fusing with each other. Every time a cell divides, some part of the telomere is lost because it fails to replicate completely, and it gets shorter. When the telomeres become too short, the chromosomes can no longer replicate. The cell becomes old and dies.
The implications of telomere length:
• As telomere length shortens with age, the rate of telomere shortening may indicate the rate of aging, which may differ between individuals of the same age.
• Certain healthy lifestyle factors may potentially reduce the rate of telomere shortening, such as a healthy diet, ample physical activity, manageable stress levels and happy relationships. Lifestyle choices plays a major role in how you will age, while studies have indicated that a healthy diet and vigorous aerobic exercise play a definite role in reducing the rate of telomere shortening in healthy older people.
• Certain unhealthy lifestyle factors may potentially increase the rate of telomere shortening, such as obesity, lack of physical activity, high levels of stress, smoking and unhappiness.
• In germline cells, such as sperm, egg cells from the ovary and in fetal tissues, an enzyme called telomerase elongates chromosomes. In adult cells the telomere length gradually shortens as the body ages.
• Telomere lengthening is regarded by scientists to hold the key to explaining the process of aging and although this science is still in its infancy, it holds the promise of one day slowing the process of aging.
• Cancer cells are malignant cells that divides more often until they form a tumor that can potentially grow uncontrollable. The telomeres get shorter during this process and if it gets too short the cell may die. However, increased telomerase activity has been detected in cancer cells and found to be 10 – 20 times more active than in normal cells, allowing the cancerous cell to avoid dying as a normal cell would.
• The danger of overexpressing telomerase to end up with longer telomeres is that it may increase the risk for cancer.
• Scientists at the Stanford University School of Medicine has, under laboratory conditions, come up with a procedure that can increase the length of human telomeres (and consequently increase the rate of cell division) in cultured muscle and skin cells, yielding large numbers of cells for studies such as drug testing or disease modelling. This increased telomere production, however, dissipates and is gone after 48 hours, after which time the normal rate of telomere shortening commences. This is a first step that may pave the way for the development of telomere extensions to prevent or treat diseases related to aging – but much more research is needed to fully understand these processes.
Sources:
Facts about telomeres and telomerase. Published by the Shay/Wright Lab. The University of Texas Southwestern Medical Center. (www.utsouthwestern.edu)
Telomeres, lifestyle, cancer, and aging. Published January 2011. US National Library of Medicine. National Institutes of Health. (www.ncbi.nlm.nih.gov)
Are telomeres the key to aging and cancer? Published by Learn.Genetics. University of Utah Genetic Science Learning Center. (www.learn.genetics.utah.edu)
How to lengthen your telomeres & unlock the key to longevity. Published on Dr. Axe. (www.draxe.com)
Telomere extensions turns back aging clock in cultured human cells, study finds. Published 22 January 2015. Stanford University School of Medicine. (www.med.stanford.edu)
Lifestyle changes may lengthen telomeres, a measure of cell aging. Published 16 September 2013. University of California San Francisco. (www.ucsf.edu)
The search for extended youth and extreme longevity. Published online 5 May 2018. Dr. Mercola. (www.drmercola.com)
HEALTH INSIGHT
MAY 2018