What is the relationship between syndromes as HGPS and normal aging?
In the past I was very hopeful about results coming from studies performed with progeroid syndromes. I expected them to shed some light into the processes that are involved in normal senescence. Nowadays, however, I believe that they have taught us all that the could. I think that aging is due to two different causes:
- Cancer avoidance systems: Cell cycle arrest, and preventive apoptosis.
- Imperfect repair systems: Accumulation of errors that induce cancer avoidance systems in damaged cells. They either die or stop dividing/working properly.
In all the progeroid syndromes there is at least one of these situations:
- The repair systems do not work at peak efficiency.
- There is a disturbing factor that increases the amount of damage to the organism.
So far, we have found no clue of a senescence regulating system. There are ways to slow aging, of course (we will talk about them in later entries), but all of them seem not to clearly increase the overall fitness of the individual.
I rather prefer to die at 75 of an infection that I could easily cope with if I am only 30, than not getting to 75 because I die of cancer at 40. I believe that natural selection thinks the same as me in this case, so it has optimised our repair/kill/arrest systems to get the most of them.
If we want to live significantly longer we have to reengineer both our repair and anticancer systems.