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Telomeric Theory - Related Research - CR

Excelife excelife at earthlink.net
Sat Sep 19 00:30:27 EST 1998


D) Calorie/Dietary Restriction

While not substantially related to the telomeric theory of aging Dietary 
Restriction is a possible adjunct to the research.  It is one of the few 
methods known to have any noticeable impact on the extension of life span.

Several research findings indicate that one possible reason Dietary 
Restriction has this effect are related to the telomeres.  In several studies 
it has been shown that cellular replication is slowed and replicative 
potential preserved in mice on calorie restriction.  By slowing the 
replicative activity in the cells the telomeres are preserved for a longer 
period of time and the cells thus enter senescence later in the life cycle.

This strategy of maintaining individual cells for a longer period to delay 
the shortening of the telomeres through mitotic division is an interesting 
phenomena.  In Dietary restricted mice it is apparently caused by a lack of 
the "energy" needed to initiate mitosis.  It may be possible to obtain 
similar results through intervention in the cellular energy transport systems 
or even by delaying the cellular signals leading to replication.

Another area where Dietary Restriction overlaps with the telomeric theory is 
in it's effects on senescent cells.  Dietary Restriction has been shown to 
increase the initiation of apoptosis in senescent cells.  The mechanism(s) 
driving this action have not been identified but the effects are beneficial 
to the organism.  Beyond the natural effects of eliminating the damage caused 
by senescent cells, studies by Dr. L. Effros have shown that elimination of 
these cells also allows for their replacement by more functional cells.

Since senescence is the result of shortened telomeric length, Dietary 
Restriction may recognize this state as damage.  Possibly when both the 
energy level is insufficient for replication, as shown above, and the p-53 
gene is expressed as a result of telomeric shortening then the cell initiates 
apoptosis.  This is just a hypothesis but one I feel deserves to be explored.

(Next:Telomeres and Growth Factors)

Thomas Mahoney, Pres.
Lifeline Laboratories, Inc.

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