【"Genes" in the Nobel Prize】
"Life, old age, illness and death" is a law that all living things cannot avoid, perhaps these phenomena are too "ordinary", for a long time people forget to explore the mechanism behind it. Until the late 1970s, Elizabeth H. Blackburn discovered through research that there was a DNA fragment called a "telomere" at the end of the chromosome, which could avoid mutual wear and adhesion between chromosomes and play a role in protecting the chromosome. However, each division of an organism's cells shortens the telomeres. When telomeres are shortened to a certain extent, the cells either die, or stop dividing and go into a dormant state. This property makes telomere length one of the indicators of cellular aging. In some cells, a protein called telomerase is able to resynthese the missing part of telomerase; in others, telomeres continue to shorten. In 2009, Blackburn, along with her graduate students Carol W. Geider and Jack W. Szostak, was awarded the 2009 Nobel Prize in Physiology or Medicine for their outstanding contributions to the study of telomere mechanisms. So how are "telomeres" discovered? Understanding how it works, can we really fight aging?
Elizabeth H. Blackburn
"Pond Litter"
Born into a family of doctors in Australia, Elizabeth H. Blackburn learned well from an early age, and after graduating from secondary school, she received a scholarship and entered the University of Melbourne, obtaining a bachelor's and master's degree in biochemistry in 1970 and 1972, and then obtained a doctorate in biology from the University of Cambridge in the United Kingdom in 3 years, proficient in DNA related knowledge. Subsequently, she went to Yale University and the University of California, San Francisco to carry out postdoctoral research. During her research at Yale, she began to focus on the replication of tetramembrane chromosomes. She is very interested in the function of telomeres in chromosomes. In 1980, she met Jack W. Shostak, who was also passionate about studying telomeres, and they began collaborating on research. Then, in 1984, Elizabeth and her graduate student, Carol W. Glade, jointly discovered telomerase and found that telomerase can repair the missing part of telomeres during cell division, which largely determines whether cells can continue to replicate and is the key to maintaining "vitality" in cells. Nearly 10 years of research from 1975 to 1984 led to the successful discovery and revelation of telomerase function, but there were countless difficulties in between, which made Elizabeth and her lab members suffer, and she jokingly called tetramembranes "pond garbage."
Elizabeth's findings are of great significance, and multiple studies have shown that by measuring telomere length, it can not only predict the risk of cardiovascular disease, diabetes, Alzheimer's disease and certain cancers, but even the risk of individual death. For example, Mary Whooley of the University of California, San Francisco, followed 780 people aged 60 and older for 4 years. The results confirmed that the shortening of telomeres is indeed a risk factor affecting mortality. Richard Cawthon, a geneticist at the University of Utah in the United States, conducted a 15- to 20-year study of 143 participants and found that individuals with shorter telomeres had twice as long mortality rates as individuals with longer telomeres.
Chromosomes under telomerase protection
"Longevity Advice"
There are many interesting follow-up studies around telomeres and telomerase, and this article collates 3 studies related to telomeres and longevity.
(1) Telomeres prefer a certain type of movement. A 2015 study by German scientists showed that exercises like weight lifting do not have any effect on telomerase. However, brisk walking or other light aerobic exercise of about 45 minutes three times a week can increase telomerase activity by a factor of 2. In addition, 10 minutes of warm-up, followed by 3 minutes of fast running - 3 minutes of rest (4 cycles), followed by 10 minutes of rest, 3 times a week, can also achieve the above effect.
(2) Eating more fish, kelp, and flaxseed oil helps protect our telomeres. In 2010, scientists at the University of California measured the content of Ω-3 fatty acids (omega-3s) in more than 600 middle-aged heart disease patients, and the results showed that the higher the omega-3 content, the longer the length of telomeres in the subsequent 5 years. Among them, the mortality rate of heart disease patients with longer telomeres is significantly lower than that of patients with short telomeres.
(3) Depression and anxiety can make your telomeres shorter, but meditation helps with telomere recovery. A 2014 study of 3,000 Dutch people found that the longer the depression, the higher the degree of depression and the shorter the telomeres in patients. Subsequently, the results of a 2015 study with a larger sample size (12,000 Chinese women) showed that the telomere length of women with long-term repression was significantly shorter than that of women who were not depressed. Interestingly, multiple studies have pointed out that meditation can significantly increase telomere length. Elizabeth once did the following experiment: She sent volunteers to a rehabilitation center in North Colorado, USA, and had them undergo 3 months of meditation training, and then measured their telomere length. The results showed that the telomeres of volunteers who participated in meditation were 30% longer than those who did not participate in meditation.
Meditation can "protect" our telomeres
It can be seen that scientists have established a statistically significant link between telomere shortening and disease risk, and I believe that in the near future, we can more fully use this scientific and technological knowledge to provide services for the healthy life of human beings.
Producer: Popular Science China
Author: Xu Lotian (Associate Professor, School of Life Sciences, Hubei University)
Producer: Chinese Agricultural Society Guangming Network Science Popularization Division