Youth, and appearing youthful has become the obsession of the modern
age. We only need to look at the celebrities that have gone to drastic extremes
like plastic surgery to see how important looking young can be. Those
same people will be happy to hear that new developments could lead to
therapies that drastically lessen the rate of ageing at the cellular level,
effectively allowing us to become immortal.
Whilst completing my dissertation in my final year at university, I was
intimately involved in telomeres and their maintenance, an aspect of science
which has sparked my imagination, and a component which is of crucial
importance if we were to obtain immortality. So, let’s try and put telomeres
into context for those of you who don't already know what they are.
Whilst bacteria have circular chromosomes, the linear chromosomes found
in most eukaryotic organisms require protection at their ends to prevent
degradation which is brought on by the imperfect nature of DNA replication
during a cells division. To counteract this inevitable degradation, the
structure of the telomere evolved. Telomeres are composed of stretches of repetitive sequence
which can be found on the ends of each of our chromosomes. These telomeres
protect our valuable genetic information from being lost during replication by
allowing those non-important non-coding stretches of repetitive sequences to be
lost, rather than genes which are important for our survival.
However, even these protective caps are eventually degraded after
numerous rounds of cell division and once they are, the cell that they belong
to is killed through programmed cell death (apoptosis). It is this which limits
the number of times a cell can divide (also known as the Hayflick limit) and
also results in the aging of an organism.
The secret to preventing aging in this way comes from one of the most
unlikely places, the lobster. The reason for this is that the lobster, unlike
humans, has extraordinarily high levels of telomerase, an enzyme which is
capable of replenishing telomeres, increasing their length and preventing the
ageing process. In humans, telomerase is restricted to only a few cell types,
leaving other cells types with shortened telomeres. If we were somehow capable
of harnessing the power of telomerase which gives lobsters their incredible
longevity, and place it into every cell in our body, we would be able to steal
the immortal power of lobsters for ourselves.
But don't get too excited quite yet. As I mentioned earlier, there are
cell types in the human body which contain high levels of telomerase, one of
which are cancer cells. One of the defining characteristics of cancer is its
ability to produce telomerase, allowing it to replicate an infinite amount of
times until it forms a tumorous growth. This means that if we were able to
increase the length of our telomeres, we would be opening ourselves up to a
much higher likelihood of contracting a wide spectrum of different
cancers.
This means that at the moment cancer and the
concepts behind immortality go hand in hand. However, with advances in the
fields of both telomeres and cancer being made every day, this isn't an idea
which should be shrugged off and ignored.
So there we have it, we do indeed hold the key to
immortality. Who'd have thought that Sebastian from the little mermaid when
singing about being ‘under the sea’ could one day allow us to live forever? But
what would you do if you knew you wouldn't die from old age? Is death something
you'd try hard to avoid, or is it just a normal part of life, something that
unites us all and something that we all have to go through? Comment below
with your thoughts.
