Turn Back Time with Telomere Extension
As we age, the protective ends of our linear chromosomes known as telomeres, shorten. Telomeres are sequences of repeated DNA material that caps every chromosome in the body. The job of telomeres is to protect the genetic materials within the chromosomes. When DNA replicates, these telomeres shorten. This process is a sign of molecular aging and is associated with the development of diseases related to aging such as arthritis. 1 With this in mind, the lengthening of these telomeres influences longevity, while environmental factors can have an impact on how quickly telomeres erode. It stands to reason that, in order to address age-related diseases, that the lengthening of telomeres is in order. Here is an overview of this fascinating subject that may lead to the fountain of youth many seek.
In 2015, researchers discovered a number of molecular pathways that are the main molecular causes of aging, such as telomere attrition, cellular senescence, stem cell exhaustion, mitochondrial dysfunction, and epigenetic alterations. 1 The erosion of telomeres is a primary cause of aging and can begin the cascade of processes mentioned above. 1 As the telomeres shorten, their ability to renew tissues is greatly reduced, leading to age-related conditions noted above. When this occurs prematurely, it can also hasten a premature loss of the ability for tissues to self renew and, subsequently, the loss of DNA damage checkpoints that lead to chromosome end-to-end fusions, genomic instability, and age-related diseases. 1
Can telomere extension turn back time?
Scientists have investigated telomere extension as a way to extend lifespan. It is thought that by keeping telomeres strong and healthy that longevity can occur. In a recent study, researchers discovered that when induced pluripotent stem cells are allowed to divide, the result is extra- long telomeres. These embryonic cells were then used to breed chimaeric mice without genetically modifying them. The result was mice that lived an average of 24% longer, while also being slimmer and less likely to develop cancer. 2 Factors contributing to metabolic aging were also lower in the mice, and their DNA wasn’t as compromised as the mice aged. The mitochondria for the mice also functioned better. This study clearly links telomere length with longevity and opens the potential for more investigation into how it can be applied with humans, especially considering the many aspects of modern life such as toxic burden from pollution, PCBs, and other factors that contribute to accelerated aging.
1. Bär C, Blasco MA. Telomeres and telomerase as therapeutic targets to prevent and treat age-related diseases. F1000Res. 2016;5:F1000 Faculty Rev-89. Published 2016 Jan 20.
2. Muñoz-Lorente, M.A., Cano-Martin, A.C. & Blasco, M.A. Mice with hyper-long telomeres show less metabolic aging and longer lifespans. Nat Commun 10, 4723 (2019).