11 ms·

Blood of world's oldest woman hints at limits of life

162 points by happyscrappy 13y ago

veew 13y ago
no limits, let's go for the gold, boys.
jostmey 13y ago
Our body contains literally trillions of cells. It is absurd to think that among all these cells there will be only a few mutations. Mutations will occur in all cell types all over the body. What I find really interesting is that the mortality distribution in Gompertz's law may be predicted using the Euler-Lotka equation. This says that the reason we die is because there is an absence of selective pressure for the individual in a species to live longer (link: http://www.genetics.org/content/156/3/927.full.pdf http://www.genetics.org/content/156/3/927.full.pdf)
- s_baby 13y ago
  >This says that the reason we die is because there is an absence of selective pressure for the individual in a species to live longer Or there is a selective pressure making sure organisms don't have indefinite lifespans. You need death for a constant stream of sexual reproduction.
  - Houshalter 13y ago
    The longer an organism lives the more it can reproduce, the more copies of it's genes there will be. Any gene that increases (reproductive) lifespan is strongly selected for.
    - datadata 13y ago
      It seems like the rate of reproduction rather than total reproductive lifespan is what matters for selection. A longer lifespan at the expense of a lower rate of reproduction would not be selected for.
      - Houshalter 13y ago
        I don't see any reason why this would require that tradeoff.
    - samatman 13y ago
      Not correct, though intuitive. Consider each offspring to be 50% of the genes of the parent. A parent with three children is competing with hir own genetics, and losing.
      - Houshalter 13y ago
        Your reasoning makes no sense. If the parent can live longer they can reproduce more and therefore propagate more of their genes.
        samatman 13y ago
        It does. 150% (more than the parent) of the genes have teamed up with a foreign 150% of genes against the parent.
exratione 13y ago
For my money the nuclear DNA damage angle is actually the more interesting part of this. The research community has for some years been debating whether or not stochastic nuclear DNA damage is important in aging outside of the issue of cancer. The consensus educated assumption has long been to think of course, nuclear DNA damage should lead to loss of protein homeostasis, and is therefore a meaningful contributing cause of aging, not just of raised risk of cancer. However there is nowadays plenty of evidence to support the opposite view, that the levels of stochastic nuclear mutations seen in human tissues really don't matter over the present human life span. Other than cancer. This would be good if it continues to hold up. The less we have to fix in order to produce a first generation of treatments that effectively treat aging - i.e. produce rejuvenation - the better. Fixing nuclear DNA damage is going to be plausible via global DNA editing technologies like CRISPR, but we're a long way from doing it for all genes to restore to a template and erase damage. Cancer therapies on the other hand are going to improve enormously in the near future as forms of narrowly targeted cell destruction take over from the present standards of chemotherapy and radiotherapy, coupled with greatly improved early detection. If you're 20-40 years away from peak cancer age in a wealthy region of the world, then I don't think your odds of dying from cancer are very large at all.
- sspiff 13y ago
  You say this as if rejuvenation would be a good thing. Rejuvenation would further divide the poor from the rich, as the poor are unable to afford such treatment. Wealthy dynasties would continue to acquire wealth (because wealth builds more wealth), while one of the current rebalancing mechanisms (people dying without heirs) would be significantly reduced or even completely disappear. Furthermore, we'd have even more competition over the limited amount of resources and habitable land than we have today. Let's just hope we figure out that space thing before they ever figure out rejuvenation.
  - rch 13y ago
    Don't worry, I'm sure there will be rejuvenation visas for engineers who are willing to work at a discount for the remainder of their extended lives.
solox3 13y ago
Older people die from not being able to perform mitosis of vital cells (http://www.ncbi.nlm.nih.gov/pubmed/12573379 http://www.ncbi.nlm.nih.gov/pubmed/12573379) -- a decade-old observation. She is just a new, other data point.
logfromblammo 13y ago
I wonder if the technology and the knowledge will ever be at the point where "life hackers" are extracting their own stem cells, applying home-brewed telomerase, and reinjecting them. It seems like the sort of thing that a subset of HN folks would do.
- happyscrappy 13y ago
  The article mentions that possibly all you would have to do is remove some stem cells at a young age and inject them when you are older. Presumably the cells would be kept alive at very low metabolism so they don't divide much.
- jasonford1 13y ago
  I met a woman at the first Quantified Self (http://quantifiedself.com/ http://quantifiedself.com/) conference who was very much into such activities. She wasn't performing the process you described, but she absolutely would be willing. Experimenting with biology in your own homemade closet lab becomes more and more financially feasible everyday.
- atrus 13y ago
  I would hope not, as simply extending telomeres is a fantastic way to give yourself cancer.
  - logfromblammo 13y ago
    It is my understanding that some forms of cancerous cells extend their own telomeres, so having stem cells with shorter telomeres is not a defense against this. In any case, wouldn't the cancer be the result of damage to the coding DNA or the intercellular environment anyway, and not a function of telomere length? The telomeres are there to ensure that the cells with more transcription errors die first. But in the case of aging, there are no younger cells for this die-off process to prefer. Given the choice between a certainty of cancer and cells that cannot even reproduce, some people may roll the dice with cancer, and hope they can live long enough to overcome that problem as well.
- 13y ago
naterator 13y ago
Meta: I love that lately there have been more health and biology related submissions here on HN. Dovetails nicely with YC new shift/interest, and matches one of my great personal interests. Do other like this as well, or do people wish that HN would stay focused on software, VC, and traditional tech? Just curious. Obviously it's getting upmodded, but still curious to hear if there is another side.
- alandarev 13y ago
  Technology by itself, existing inside of computers alone, limits the possibilities of impacting our lives. Companies which manage to use technology to actually change the lives of people usually cause greater impact overall, and I am just as you happy to read articles of such examples. In this case, it isn't a ready product, nor any change at this point, but a fundamental step towards.
- judah 13y ago
  Technology + medicine = huge advancement for humanity. This really is a frontier that has yet to come to full fruition. I'm all for YC/HN spreading into biology and medicine. Personally, it is an area I'd like to move towards in my own career. I love web development and technology, but I'd love it more if I could apply it to medicine in some way, to produce a more tangible benefit to humanity.
eyko 13y ago
Does this mean that donating blood reduces your number of white blood cells, and hence your life?
- saalweachter 13y ago
  My vague understanding is that your blood stem cells are in your bone marrow.
  - nightcracker 13y ago
    Yes, but the article suggests that the amount of blood they can produce is limited in your lifetime before they burn out. So the question still stands: does donating blood mean a shorter maximum lifespan, because you can no longer replenish your own blood cells?
    - zo1 13y ago
      Next we'll have conspiracy theorists claiming that blood-donation drives are a conspiracy by the 1% or the rich to kill off the poor!!
    - saalweachter 13y ago
      Hmmm, my guess would be probably not? The internet says that white blood cells only live 3-4 days. If you donate 1 of your 10 pints of blood every 8 weeks, and your body actually replaces the white blood cells immediately (instead of just being down 10% for 3-4 days), you would only be increasing white blood cell production by about 0.7%.
gameshot911 13y ago
This part caught my interest: "Holstege says the results raise the possibility of rejuvenating ageing bodies with re-injections of stem cells saved from birth or early life. These stem cells would be substantially free of mutations and have full-length telomeres." Makes me wonder if I should take a blood sample now (age 26) and have it frozen on the off chance that it would be of use later in life. Basically a hedge against, 50 years from now, "well we have the amazing rejuvenation technology that can replenish the fresh blood cells, but only if we have a sample of 'young' blood. Sorry everyone aged 60+."
- DEinspanjer 13y ago
  Yep. I jumped to the exact same conclusion. I did a quick search to see what was out there and I came across this article from 2008 talking about a few such companies and how it was being discounted by many scientists as not likely to be useful: http://www.nytimes.com/2008/01/29/health/29stem.html?pagewanted=all http://www.nytimes.com/2008/01/29/health/29stem.html?pagewan... At least a couple of the companies mentioned in that article appear to be out of business. The prices quoted back then are non-trivial for middle class Americans. It still seems like the sort of thing that might be worth the expense. If they come up with the solution when I'm 80, but I don't have any source of young stem cells to rely on... Same goes doubly for my kids.
  - jebus989 13y ago
    This really isn't worth worrying about. I know it seems like a Pascal's wager scenario but "youth of stem cells" isn't a problem. We know how to lengthen telomeres (hTERT) and generating human iPSCs is a routine procedure.
- higherpurpose 13y ago
  I think that would be wise. We don't know what kind of technology we'll have in 50 years. On the other hand, perhaps it will be so advanced that you won't even need your own stem cells to get rejuvenated. Would that be possible?
  - 13y ago
cab_codespring 13y ago
I wonder if there is a way to save some of your stem cells now, while you are are younger, just in case the technology is available when you are older.
grok2 13y ago
A comment in this article about the "worn-down" telomeres in the lady's white-blood cells makes me wonder if it would be possible to study the size of white-blood telomeres in any person relative to their brain cell telomeres and predict how long someone is likely to live (given no other health problems)...

162 points by happyscrappy 13y ago

veew 13y ago

no limits, let's go for the gold, boys.

Our body contains literally trillions of cells. It is absurd to think that among all these cells there will be only a few mutations. Mutations will occur in all cell types all over the body. What I find really interesting is that the mortality distribution in Gompertz's law may be predicted using the Euler-Lotka equation. This says that the reason we die is because there is an absence of selective pressure for the individual in a species to live longer (link: http://www.genetics.org/content/156/3/927.full.pdf http://www.genetics.org/content/156/3/927.full.pdf)

s_baby 13y ago
>This says that the reason we die is because there is an absence of selective pressure for the individual in a species to live longer Or there is a selective pressure making sure organisms don't have indefinite lifespans. You need death for a constant stream of sexual reproduction.
- Houshalter 13y ago
  The longer an organism lives the more it can reproduce, the more copies of it's genes there will be. Any gene that increases (reproductive) lifespan is strongly selected for.
  - datadata 13y ago
    It seems like the rate of reproduction rather than total reproductive lifespan is what matters for selection. A longer lifespan at the expense of a lower rate of reproduction would not be selected for.
    - Houshalter 13y ago
      I don't see any reason why this would require that tradeoff.
  - samatman 13y ago
    Not correct, though intuitive. Consider each offspring to be 50% of the genes of the parent. A parent with three children is competing with hir own genetics, and losing.
    - Houshalter 13y ago
      Your reasoning makes no sense. If the parent can live longer they can reproduce more and therefore propagate more of their genes.
      - samatman 13y ago
        It does. 150% (more than the parent) of the genes have teamed up with a foreign 150% of genes against the parent.

exratione 13y ago

For my money the nuclear DNA damage angle is actually the more interesting part of this. The research community has for some years been debating whether or not stochastic nuclear DNA damage is important in aging outside of the issue of cancer. The consensus educated assumption has long been to think of course, nuclear DNA damage should lead to loss of protein homeostasis, and is therefore a meaningful contributing cause of aging, not just of raised risk of cancer. However there is nowadays plenty of evidence to support the opposite view, that the levels of stochastic nuclear mutations seen in human tissues really don't matter over the present human life span. Other than cancer. This would be good if it continues to hold up. The less we have to fix in order to produce a first generation of treatments that effectively treat aging - i.e. produce rejuvenation - the better. Fixing nuclear DNA damage is going to be plausible via global DNA editing technologies like CRISPR, but we're a long way from doing it for all genes to restore to a template and erase damage. Cancer therapies on the other hand are going to improve enormously in the near future as forms of narrowly targeted cell destruction take over from the present standards of chemotherapy and radiotherapy, coupled with greatly improved early detection. If you're 20-40 years away from peak cancer age in a wealthy region of the world, then I don't think your odds of dying from cancer are very large at all.

sspiff 13y ago
You say this as if rejuvenation would be a good thing. Rejuvenation would further divide the poor from the rich, as the poor are unable to afford such treatment. Wealthy dynasties would continue to acquire wealth (because wealth builds more wealth), while one of the current rebalancing mechanisms (people dying without heirs) would be significantly reduced or even completely disappear. Furthermore, we'd have even more competition over the limited amount of resources and habitable land than we have today. Let's just hope we figure out that space thing before they ever figure out rejuvenation.
- rch 13y ago
  Don't worry, I'm sure there will be rejuvenation visas for engineers who are willing to work at a discount for the remainder of their extended lives.

solox3 13y ago

Older people die from not being able to perform mitosis of vital cells (http://www.ncbi.nlm.nih.gov/pubmed/12573379 http://www.ncbi.nlm.nih.gov/pubmed/12573379) -- a decade-old observation. She is just a new, other data point.

logfromblammo 13y ago

I wonder if the technology and the knowledge will ever be at the point where "life hackers" are extracting their own stem cells, applying home-brewed telomerase, and reinjecting them. It seems like the sort of thing that a subset of HN folks would do.

happyscrappy 13y ago
The article mentions that possibly all you would have to do is remove some stem cells at a young age and inject them when you are older. Presumably the cells would be kept alive at very low metabolism so they don't divide much.
jasonford1 13y ago
I met a woman at the first Quantified Self (http://quantifiedself.com/ http://quantifiedself.com/) conference who was very much into such activities. She wasn't performing the process you described, but she absolutely would be willing. Experimenting with biology in your own homemade closet lab becomes more and more financially feasible everyday.
atrus 13y ago
I would hope not, as simply extending telomeres is a fantastic way to give yourself cancer.
- logfromblammo 13y ago
  It is my understanding that some forms of cancerous cells extend their own telomeres, so having stem cells with shorter telomeres is not a defense against this. In any case, wouldn't the cancer be the result of damage to the coding DNA or the intercellular environment anyway, and not a function of telomere length? The telomeres are there to ensure that the cells with more transcription errors die first. But in the case of aging, there are no younger cells for this die-off process to prefer. Given the choice between a certainty of cancer and cells that cannot even reproduce, some people may roll the dice with cancer, and hope they can live long enough to overcome that problem as well.
13y ago

naterator 13y ago

Meta: I love that lately there have been more health and biology related submissions here on HN. Dovetails nicely with YC new shift/interest, and matches one of my great personal interests. Do other like this as well, or do people wish that HN would stay focused on software, VC, and traditional tech? Just curious. Obviously it's getting upmodded, but still curious to hear if there is another side.

alandarev 13y ago
Technology by itself, existing inside of computers alone, limits the possibilities of impacting our lives. Companies which manage to use technology to actually change the lives of people usually cause greater impact overall, and I am just as you happy to read articles of such examples. In this case, it isn't a ready product, nor any change at this point, but a fundamental step towards.
judah 13y ago
Technology + medicine = huge advancement for humanity. This really is a frontier that has yet to come to full fruition. I'm all for YC/HN spreading into biology and medicine. Personally, it is an area I'd like to move towards in my own career. I love web development and technology, but I'd love it more if I could apply it to medicine in some way, to produce a more tangible benefit to humanity.

eyko 13y ago

Does this mean that donating blood reduces your number of white blood cells, and hence your life?

saalweachter 13y ago
My vague understanding is that your blood stem cells are in your bone marrow.
- nightcracker 13y ago
  Yes, but the article suggests that the amount of blood they can produce is limited in your lifetime before they burn out. So the question still stands: does donating blood mean a shorter maximum lifespan, because you can no longer replenish your own blood cells?
  - zo1 13y ago
    Next we'll have conspiracy theorists claiming that blood-donation drives are a conspiracy by the 1% or the rich to kill off the poor!!
  - saalweachter 13y ago
    Hmmm, my guess would be probably not? The internet says that white blood cells only live 3-4 days. If you donate 1 of your 10 pints of blood every 8 weeks, and your body actually replaces the white blood cells immediately (instead of just being down 10% for 3-4 days), you would only be increasing white blood cell production by about 0.7%.

gameshot911 13y ago

This part caught my interest: "Holstege says the results raise the possibility of rejuvenating ageing bodies with re-injections of stem cells saved from birth or early life. These stem cells would be substantially free of mutations and have full-length telomeres." Makes me wonder if I should take a blood sample now (age 26) and have it frozen on the off chance that it would be of use later in life. Basically a hedge against, 50 years from now, "well we have the amazing rejuvenation technology that can replenish the fresh blood cells, but only if we have a sample of 'young' blood. Sorry everyone aged 60+."

DEinspanjer 13y ago
Yep. I jumped to the exact same conclusion. I did a quick search to see what was out there and I came across this article from 2008 talking about a few such companies and how it was being discounted by many scientists as not likely to be useful: http://www.nytimes.com/2008/01/29/health/29stem.html?pagewanted=all http://www.nytimes.com/2008/01/29/health/29stem.html?pagewan... At least a couple of the companies mentioned in that article appear to be out of business. The prices quoted back then are non-trivial for middle class Americans. It still seems like the sort of thing that might be worth the expense. If they come up with the solution when I'm 80, but I don't have any source of young stem cells to rely on... Same goes doubly for my kids.
- jebus989 13y ago
  This really isn't worth worrying about. I know it seems like a Pascal's wager scenario but "youth of stem cells" isn't a problem. We know how to lengthen telomeres (hTERT) and generating human iPSCs is a routine procedure.
higherpurpose 13y ago
I think that would be wise. We don't know what kind of technology we'll have in 50 years. On the other hand, perhaps it will be so advanced that you won't even need your own stem cells to get rejuvenated. Would that be possible?
- 13y ago

cab_codespring 13y ago

I wonder if there is a way to save some of your stem cells now, while you are are younger, just in case the technology is available when you are older.

grok2 13y ago

A comment in this article about the "worn-down" telomeres in the lady's white-blood cells makes me wonder if it would be possible to study the size of white-blood telomeres in any person relative to their brain cell telomeres and predict how long someone is likely to live (given no other health problems)...