Michelangelo’s Statue of David is about 506 years old. The statue is in excellent shape despite its significant age and now stands in the Galleria dell’Accademia in Florence. Michelangelo on the other hand is now dead; and has been since February 18, 1564. What happened? Why do the atoms of David remain in their fixed shape, as they were when Michelangelo finished the statue so long ago? And why did Michelangelo’s atoms change their composition to such an extent that he lost his consciousness and physical structure? Michelangelo is not the only person with this issue. All compositions granted the title of “Life” have the same problem; they change, and they die.
Recent research into this phenomenon has revealed that organisms have a “program” that drives aging and consequently death. It is called Apoptosis, or programmed cell death. Apoptosis is triggered by many cell signals. Some of these signaling pathways target cells’ mitochondria. Mitochondria are essential to a cell’s survival and without proper mitochondrial functioning, the cell quickly dies. One pathway that is considered as part of the aging “program” is the insulin/insulin growth factor 1 receptor signaling pathway. When insulin or insulin growth factor bind to their respective receptors, it triggers a chain of intracellular events that has been implicated in aging. This is what is meant by aging “program” and this program occurs naturally. The gene daf-2 codes for the common insulin/IGF1 receptor in the worm, Caenorhabditis elegans. This worm can undergo a daf-2 gene mutation that can double its maximum lifespan. The mutation works by preventing the signaling of the insulin/IGF1 receptor pathway. So what does this mean for humans?
Not a whole lot at this point. Insulin and insulin growth factor have a much more diverse role in humans, so a simple gene mutation of this kind cannot work. But this isn’t to say we aren’t close. In fact, I think we are very close. What if we figure the program out and stop it? Could we double our lifespans? Could we eliminate natural, programmed death completely? This is something we must consider. The current generation will be living through a technological revolution unparalleled to any in history. Overpopulation and the distribution of the technology are just two of the many issues we can identify in foresight, and hindsight has a habit of revealing to us plenty of other issues we never really considered. David might not be all that different from us. He has to be well taken care of or natural occurrences, mainly weather and the work of humans, would destroy him just like nature destroys us.
The following is a good link on aging if you want to know more: http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.0030129
Why Age?
