141–150 of 173 posts
Earlier quoted context omitted.
Pets often live longer after being neutered or spayed so it's interesting to see a correlation in humans.
Based on this observation I posed this question on /r/AskMen some time ago. "Would you be castrated to live 15 years longer?" - overwhelmingly the answer was no.
"As a worm ages, the quality of its eggs or sperm declines — what we refer to as the ticking of a biological clock. The decline is also reflected in the germ cells’ changing ability to transmit signals from the brain’s mitochondria, he suggested. As the worm grows older, its germline transmits the repair signal less effectively, and so its body declines, too. Scientists don’t yet know whether these findings apply to…
Uri Alon[1] argues thar it's the exponential growing chance of diseases/malfunctions as the amount of senescent cells surpasses certain thresholds.
Earlier quoted context omitted.
Pets often live longer after being neutered or spayed so it's interesting to see a correlation in humans.
Based on this observation I posed this question on /r/AskMen some time ago. "Would you be castrated to live 15 years longer?" - overwhelmingly the answer was no.
Earlier quoted context omitted.
Yes, the interesting thing here is that it's the germ cell mitochondria that seem to be the originators of the signal. The article's findings are also backed by data on Eunuchs who live almost 20 years longer than non-castrated men. Now the real question is: Are Bryan Johnson and his followers willing to take logical next step?
Well we need to know what do eunuchs do with the extra 20 years?
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> I think the common notion is that the survival of the individual is exactly what natural selection is selecting for. when we reproduce, do we make copies of ourselves? no we don't. It's not survival of individuals. Read the Selfish Gene and it will change your thinking. You as an individual are a piece of clothing for your genes. Your genes reproduce, you don't.
>when we reproduce, do we make copies of ourselves? You have been blessed not to grow up with a narcissist or vicarious striver as a parent. Technically, cars are a means of transportation for people. However, an honest assessment of the American transit system might lead one to believe that the safety and comfort of cars (or the automotive industry and ecosystem) are more important than the people they're supposed t…
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So take a copy when you’re 21 and store it, re-load it every 10 years?
That’s the basic idea, the problem is how do you reload it? You would need a mechanism that changes the DNA for every one of the trillions of cells in the body.
You know, I've recently wondered quite a bit about aging and how any of it makes sense. What has perplexed me is the notion of honest signals[1] in a world governed by natural selection and the survival of the fittest. Why wouldn't cheating exclusively emerge as the only strategy? Why wouldn't a species evolve a mechanism to survive longer and longer till it completely dominates? Then it dawned on me that the surviva…
> survival of the species is not aligned with the survival of an individual The unit of survival is not the individual or the species, but the gene. Genes maximize their survival by combining via sexual reproduction with other genes over time. Any one combination of genes will be out-competed over time. The reason for honest aging signals is that a gene survives longer by getting out of the way of its offspring's com…
All models are wrong but this one is mine, IANA biologist, yadda yadda.
- there are only so many resources to sustain individuals
- ergo there's a cap of the number of individuals
- ergo some individuals will die, if not from age, from attrition
- if age is not factored in, there are more old individuals, genetic competition between young individuals is reduced as they have to compete for resources with old individuals
- ergo age which kills old individuals irrespective of available resources allows more young individuals to exist in such a pool
- ergo ageing a) promotes competition between young individuals b) increases mixing of the gene pool
- ergo it promotes quicker turnaround on mutations
- ergo ageing is a significant asset in species adaptability to change
IOW vendor lock-in sucks in face of changing conditions as one is suddenly stuck with a suboptimal solution and competitors have a harder time emerging to challenge the status quo.
conversely the benefits of short term ageing are counterbalanced by social effects, where elders, even when not reproductive anymore but still otherwise in good health and thus autonomous as well as minimally consuming resources, are able to provide support for their chain of descendants, freeing energy for parents-to-be to reproduce, then parents to gather more resources that are then directed to support their younglings. The lack of reproductiveness of elders is advantageous to the species as it removes them from the direct gene mixing pool, instead promoting the younger ones.
IOW for its individual lives to be longer, a species goes increasingly social, channeling more support and thus energy towards their younger members, but ageing is still key otherwise the species ability to face quick change (at evolutionary scales) is severely hampered.
The deeper question for me is whether ageing is a specific primary process (a literal clock, which a technique such as the paper would attempt to skew backwards) that emerged from evolution or if it is a secondary effect from entropy corrupting other processes (e.g there's constant degradation + a ton of error correction but at some point degradation is too high and error correction cannot cope, triggering a catastrophic cascading effect leading to the sudden inability for an organism to sustain its own life, which the paper would delay by introducing younger cells, thus less errors, thus error correction can cope for longer)
"As a worm ages, the quality of its eggs or sperm declines — what we refer to as the ticking of a biological clock. The decline is also reflected in the germ cells’ changing ability to transmit signals from the brain’s mitochondria, he suggested. As the worm grows older, its germline transmits the repair signal less effectively, and so its body declines, too. Scientists don’t yet know whether these findings apply to…
ok probably stupidly curious: A study of 81 historical eunuchs in Korea's royal court found a 14- to 19-year increase in lifespan compared to intact men of similar socioeconomic background; these eunuchs had a centenarian rate of over 3%. https://en.wikipedia.org/wiki/Castration#Medical_consequence...
Yet I wonder if those eunuchs had their testes removed, the WP article tells about removing the penis. If this is the case the eunuchs' testes were still there.
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Effective advocacy begins with letting go of the assumption that everyone already knows about the things you know about. I'm sure this person is well known within the bioscience community, but this is the first time I'd heard of him or his model. https://www.nad.com/news/harvard-professor-david-sinclairs-i...
> This technique also extended the lifespan of mice with a premature aging condition by about 40%. Why is it always like this? Even "in mice" I think they always start with an animal that has been genetically modified to age faster or show some trait of aging and then cure that, as opposed to taking a normal healthy mouse and extending its age by 40%, no?
Because it is an easy way to write a paper?
Even with the genetic line, same chow and environment, it's possible to have mice that are ill in one location and healthy in another.
https://www.alzforum.org/news/research-news/gut-microbes-dif...
I've come to think mitochondria are somehow fundamental to health in ways we can't even see. No sources, but they seem relevant to structure of the overall organism, proper healing of wounds, something in the brain (they can move between neurons), apoptosis, and a few other odd things I've seen talked about. They also come up in any number of diseases and conditions. All far beyond what you'd expect from "powerhouse…
I'm primed to agree as I like running, and running appears to increase mitochondrial function and density. It also appears to have some anti aging effects, which would track.