[ExI] Product B

[Rafal Smigrodzki]

On Wed, Apr 11, 2012 at 3:26 AM, Kryonica <kryonica at gmail.com> wrote:

>> This reminds me of when Rafal and I had our debate a few years back when I was doing my oral exams on telomeres and telomerase. My position was that shortened telomeres contributed directly to aging in addition to reactive oxygen species, Rafal's position was that they were merely a symptom and aging was entirely caused by oxidative damage to DNA, protiens, lipids, etc. I don't know if Rafal has changed his position over the years, but I still think they play a role. The lesson here is that experts disagree on the importance of telomere length in aging and how it differs between species. For example in in mice they seem to be less relevant.

### A bit of clarification is in order: I believe that aging is caused
predominantly by mutational damage to DNA affecting both coding and
regulatory regions, and some of it is likely to be due to oxidative
processes. There is also a contribution from non-mutational damage to
DNA, i.e. epigenetic changes, perhaps also some adducts. Damage to
proteins and lipids is however mostly a symptom rather than a cause of
aging. And yes, I still think that telomeres are mostly a symptom as
well, or perhaps an internal damage meter whose output contributes to
a cell's decisions about its fate, such as senescence or apoptosis.

I haven't changed my opinion on this subject in a few years which
could be evidence of being right, or getting cognitively older.

A true cure for aging would most likely also lengthen telomeres but I
doubt that a reset of telomere length by directly activating
telomerase (without affecting the underlying coding and regulatory DNA
damage) would produce a prolongation of lifespan.

>> I am all for antioxidants. I am just against paying a premium for them.

### The situation with antioxidants is a bit tricky. I used to believe
that supplementation was a good idea but I changed my mind (so maybe I
am not yet mentally ossified). Antioxidants may require very specific
dosage, not all of them are actually beneficial, there is a lot of
noisy data published, and that's why I am not taking any antioxidant
supplements - although I do maintain a high intake by consuming
chocolate, daily.

Rafal