Study of telomeres
The study of
telomeres concerns clinical and scientist
research.
Te lomeres
shorten
during aging.
Are Telomere
tests ready for Prime Time ? Download pdf.
A telomere
is a particular area constituting the end of a
chromosome.
With each time a
chromosome is duplicated, at replication's
time, telomeres are shortened. Telomeres become
too short do not protect cell any more, resulting in its death.
An enzyme,
the telomerase,
makes it possible the telomere to be
reconstituted. This enzyme is the
object of many search.
Telomeres shorten with
age, inflamation and stress. Studies showed that
short telomeres are associated with a higher
risk of aging diseases. The shortest
telomeres were observed in octogenarians. In
some 60 year old people, the probability
of dying of an infectious disease or a heart
attack appears to be much more important at
those having the shortest telomeres. Studies
showed that by stimulating telomerase it is
possible to increase the cells' lifetime
in a very important way.
In
1971,
the Russian biologist Alekseï Olovnikov
expressed for the first time the hypothesis that
the maximum lifetime of cells in culture
(limit of Hayflick) is correlated with the
progressive loss of telomeric sequences.The
telomeres act like a biological clock governing
the cells' lifetime. This theory is known under
the name of telomeric theory of aging.
In
1985, identification of telomerase is made by Elizabeth Blackburn and
Carol Greide.
In
2009
Elizabeth Blackburn et Carol Greide receive the Nobel Prize of physiology or
medicine.
In 2009 a publication shows the
lengthening of lymphocytes' telomeres
under the
influence of androgens (1) (Download pdf)
Protective
action of androgens on white blood cells of HIV
positive men (reduction of cellular destruction
from 34 to 52%) was already shown
in
1997. download pdf.
Bibliography WEB
1.Sex hormones, acting on the TERT gene, increase
telomerase activity in human primary hematopoietic cells.
Donwload pdf.
Constantine A. Stratakis and Neal S. Young, Rodrigo T.
Calado, William T. Yewdell, Keisha L. Wilkerson, Joshua A. Regal, Sachiko
Kajigaya,
From bloodjournal.hematologylibrary.org by guest on
October 22, 2012. For personal use only.
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