Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Cells across the body talk to each other about aging

quantamagazine.org

Post reply on HN
Print view View original

111–120 of 173 posts

Re: Cells across the body talk to each other about aging

#111

Post by I_Am_Nous »

m463 wrote: post #88
JumpCrisscross wrote: post #41

"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...

Pets often live longer after being neutered or spayed so it's interesting to see a correlation in humans.

Re: Cells across the body talk to each other about aging

#112

Post by throw__away7391 »

JoshTriplett wrote: post #80
ben_w wrote: post #79

Earlier quoted context omitted.

How can you be so confident about a hypothetical with zero examples? All the 90 year olds today are necessarily stuck with 90 year old brains.

Indeed. And why advocate death as the solution to a problem better handled with term limits and similar mechanisms?

Because right now you don't have the option to choose, so you try to convince yourself that the only choice you have is the one you would have picked anyway. It's quite a common phenomenon, I guess a sort of survival strategy.

Re: Cells across the body talk to each other about aging

#114

Post by throw__away7391 »

anigbrowl wrote: post #78
jdjdjdkdksmdnd wrote: post #44

how does anyone deny the epigenetic model of aging demonstrated by david sinclair?

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?

Re: Cells across the body talk to each other about aging

#115

Post by omeid2 »

JumpCrisscross wrote: post #104
omeid2 wrote: post #91

Earlier quoted context omitted.

> I don’t see why aging can’t be reversible Aging is loss of information, you can't reverse that. You can prevent it though.

> Aging is loss of information, you can't reverse that. You can prevent it though We don't understand aging well enough to say this with any confidence.

This is not true. We understand aging enough to confidently say that loss of epigenetic information is correlated to aging.

https://pubmed.ncbi.nlm.nih.gov/36638792/

Re: Cells across the body talk to each other about aging

#116

Post by cma »

atticora wrote: post #54
cma wrote: post #39

Earlier quoted context omitted.

At the individual and immediate progeny level, aging doesn't affect generation time. If there were group selection it might, as the older people displace resources for the younger, but for an individual that should be dilluted down to no real effect.

Since a given niche can only support a given population size, aging reduces generation time by hitting a ceiling on population size. Some organisms get around this by spawning thousands of offspring and all but approximately one fails fast. So that's an available trade-off. Increase individual age limits, but maintain adaptation rates by letting many immature individuals compete and die before maturity. Like spermato…

> aging reduces generation time by hitting a ceiling on population size.

That's what I meant by "if there were group selection it might, as the older people displace resources for the younger."

Re: Cells across the body talk to each other about aging

#117

Post by I_Am_Nous »

troupe wrote: post #21
huytersd wrote: post #10

Earlier quoted context omitted.

The longer you live, the less adaptable your species is. The more generations you can have in a shorter amount of time, the faster you can have beneficial mutations that help your species survive changing conditions.

I'm not seeing how longevity slows the number of generations you can have per unit of time. That seems like it would be determined by how quickly a species reproduces after being born...not how long they live.

Generally, the more individuals you have competing for resources, the more difficult it is to raise viable offspring. If there are far more elderly individuals who cannot reproduce, they are essentially preventing those resources from being used to mature offspring.

Re: Cells across the body talk to each other about aging

#118

Post by fnordpiglet »

Affric wrote: post #86
fnordpiglet wrote: post #25

Earlier quoted context omitted.

All living things have at least one cell, but they do not all operate in the same way. There’s possibility that worm cells and human cells behave similarly in this, but it’s also fully possible they behave in very dissimilar ways.

True, and obviously worms and humans aren’t closely related. With that said, this research is about how cells cooperate to form a multicellular animal. I think it would be interesting to use the results to design an experiment that could be applied to animals more closely related to humans (that with these results in hand you could get passed the animal ethics committee).

Well, it’s how mitochondria in cells in worms cooperate. We already know cells cooperate through many channels and some channels we understand quite well. This is truly only about worms right now. Obviously generalizing to other animals will be important next steps. But the title and text of the article implies a much more general understanding than we actually have. It’s not to diminish the results in the least. But science isn’t served by claiming progress we haven’t made, it makes it harder to fund the next step by building an assumption of nonexistent progress.

Re: Cells across the body talk to each other about aging

#119

Post by startupsfail »

AnthonyMouse wrote: post #110
fsckboy wrote: post #106

Earlier quoted context omitted.

> 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.

> Your genes reproduce, you don't. It's more complicated than that. Your genes reproduce, but then that child is in your care, and you teach them your values. Then your values reproduce. And then you're into nature vs. nurture. Your values can't reproduce if you have stupid genes that cause your offspring to die of cystic fibrosis, but your genes can't reproduce if you have stupid values that cause your offspring to…

Yep. The immune system is watching for that and killing you off, if you’re being a social reject. That works for any social animal. Plus for humans there’s also a suicide trick.

Re: Cells across the body talk to each other about aging

#120

Post by [deleted] »

phkahler wrote: post #56

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…

[deleted]
Post reply on HN