Results from Einstein study based on healthy centenarians
According to team that has been led by researchers of the Albert Einstein College of Medicine, Yeshiva University, there is an obvious connection between living up to 100 years and a hyperactive version of an enzyme that is responsible for rebuilding telomeres, that is, the tip ends of chromosomes. These findings have appeared in the recent issue of the Proceedings of the National Academy of Sciences.
Telomeres have vital roles in cancer, aging and other biological processes. Their significance was recognised the previous month, when three scientists were rewarded by the 2009 Nobel Prize in the field of Physiology and Medicine for having determined the structure of these telomeres as well as for having discovered the way they may help in protecting chromosomes from degrading.
Telomeres are rather small sections of specialized DNA which sit at the ends of every chromosome. Elizabeth Blackburn, a Ph.D. from the University of California, San Francisco and one of the Nobel Prize winners, has made comparison between telomeres and plastic tips that are found at the ends of shoelaces that is responsible for preventing the laces from undoing.
Every time cell division occurs, the cell’s telomeres somewhat erode and little by little becomes shorter with each subsequent cell division. In due course, the telomeres turn so short that their host cells end the division process and drift into a condition that is known as senescence. As a consequence, crucial tissues and vital organs start to stop working and the typical signs of aging follow.
While looking into the role that telomeres play in the aging process, the Einstein researchers examined Ashkenazi Jews. The reason is that these people are a homogeneous population which have previously been well studied genetically. Three groups of people were registered; 86 years old – generally healthy although very old (their average age being 97); 175 of their children; and finally 93 controls (children of parents who had lived an average lifespan).
In accordance with Gil Atzmon, a Ph.D., an assistant professor of genetics and medicine at Einstein, as well as Genetic Core Leader for The Longevity Project at Einstein’s Institute for Aging Research in addition to being a main author of the paper, telomeres represent a single piece of the puzzle that is accountable for the reason why a number of people are able to live such a long life. He advances that his research was meant to find the answers of two questions; Do persons who have an extended lifespan tend to be equipped with long telomeres? And if yes, could alterations in their genetic code for telomerase give an explanation for their long telomeres?
The answer to both of these questions turned out to be affirmative.
An associate professor of medicine and of genetics from Einstein, on top of being a lead author of the paper, Yousin Suh, Ph.D., states that he and his team suspected that people of outstanding long life are better able to sustain the length of their telomeres. He declares that they have discovered that these people owe their extended lifespan, at least to some extent, to beneficial modifications of genes that are involved in the maintenance of telomeres.
More explicitly, the researchers discovered that the participants who have been able to live till a very old age have got mutant genes in inheritance. These genes are the responsible for making their specific telomerase-making system hyper active. They are also enabled to preserve the telomerase length more efficiently. In most cases, these persons were secured from age-related illnesses like diabetes and cardiovascular disease, which are the source of the majority of deaths among older people.
According to Doctor Suh, their findings imply that telomere length and variants of telomerase genes come together to enable people to live very long lives, maybe by defending them from age-related illnesses. He further continues that they are now attempting to figure out the mechanism through which these genetic alterations of telomerase sustain the telomere length in centenarians. Eventually, it might be probable to develop drugs that imitate the telomerase that those centenarians have inherited in the first place.
Source: Eurekalert
Wed, Jun 9, 2010
Immortality, Longevity, Stem cells