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Cells across the body talk to each other about aging

quantamagazine.org

81–90 of 173 posts

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

#81
What I'm curious about is how if we are just two cells at one point in our life. Do all the human behaviours and inherent knowledge get transferred. Where is that information kept.

Even, uncontacted sentinel island tribes still behave very much like a human.

I asked ChatGPT ...

"the rough estimate for the data storage capacity of the human genome in bytes is approximately 6 billion bits .... or equivalently, 750 megabytes."

That doesn't seem like its enough.

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

#82

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…

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?

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

#83
post #64
post #47

Earlier quoted context omitted.

> But as the quality of the germ cells declines, there is no evolutionary reason to keep extending life span further; from evolution’s perspective, life exists to reproduce itself. When the individual's survival is the only selection factor, this is true - but it ceases to be the case in social species where reproductively non-viable individuals can still positively influence the reproductive chances of the young. Th…

The survival of the individual is indeed not what natural selection is selecting for. Otherwise phenomena like eusocial insects with sterile workers would not make sense. What is actually selected for, is genes that somehow promote more copies of themselves. This is the main takeaway from the book "the selfish gene". However, the example of ants and bees shows that this doesn't exactly promote long lifespan in the st…

I think the common notion is that the survival of the individual is exactly what natural selection is selecting for.

However, it seems to me its more selecting for its own particular configuration of genes, that essentially select for a signature of themself.

Within a species the configuration between individuals is generally different enough to not ellicit altruistic behaviour.

In most animals, the 50% kinship gene relatedness threshold is definitely not enough to instigate self sacrificial behaviour. The children of a usocial species have to be like 11/16ths clones of eachother. And the runt suicide mechanism that triggers in rabbits requires a brood of true clones.

The reason I think it seems the genes select for individuals is because most circumstances will recquire that the current reproductive unit at the individual level needs to stay alive long enough for a net positive replication contribution to have been made.

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

#84

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…

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?

I was not ready for that twist but honestly it wouldn’t completely shock me if he did it.

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

#85
post #50

Earlier quoted context omitted.

There is no more evolutionary pressure on lifespan after you have children since you have successfully passed on the ‘aging’ gene. We used to live much shorter lives, being able to die of old age was rare, therefore, no selection. If we start to have children at 90 years old we may be able to double our lifespans (while the ones that are unable to reproduce earlier will not pass on that inability). There is no cheati…

> There is no more evolutionary pressure on lifespan after you have children since you have successfully passed on the ‘aging’ gene. This assumes, incorrectly, that each generation of children are birthed into a new separate pocket-universe, where absolutely nothing prior generations do next--including suddenly dying--can ever affect their own trajectories. Consider genes Alpha and Beta, where Alpha kills women right…

Elephant matriarchs remember old watering holes that the herd has not visited in decades, and in extreme cases, watering holes that none of the other living members have ever seen.

In drought years these backups may end up getting the herd through the worst of it.

And it turns out that for elephants, water availability is one of the biggest limitations on reproduction. Provide a population with an artificial water source and it will explode in short order.

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

#86

Earlier quoted context omitted.

which have cells like humans

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).

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

#87
post #60
post #52

Earlier quoted context omitted.

> 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…

Why would women survive so long after menopause then ?

I think it can be instructive to look at other social mammals that range over large areas, like Orca and Elephants. They tend to lean heavily on elder females as the purveyors of tribal knowledge and inter-generational memory to remember where to go and how to get there as environmental conditions vary from year to year and decade to decade. It doesn't matter as much in humans since we have writing and maps now, but this kind of wisdom of those who remember similar lean times from 60 years ago could have been very important to the survival of human communities.

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

#88

"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...

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

#89
post #59

As you get older you find it becomes a key topic of conversation not just amongst your cells but amongst friends - the conversation always heads towards whatever ailment or problem your body has recently dealt you.

This effect, which I can confirm in more than set of friends, is one of the most annoying aspects of aging. I'd rather gossip about the cheer leaders or the football players than listen to people talk about procedures. I certain have a lot more aches and pains but I don't care to let my attention linger on them.

I think it's the inverse of an effect.

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

#90
Aging should be classified as a disease because there has to be a set of biological levers that we can manipulate with drugs or other forms of medicine which will have an effect on the aging process across the entire. Like using RNA to reprogram the cells in the body to do things outside of what’s encoded in our base DNA.

I don’t see why aging can’t be reversible, I’ve heard some people say it’s an impossible task because they equate aging with the fact that time can only move forward and therefore aging must inherit the same property. But aging is just damage that accumulates over time, but damage can be repaired with the right tools.

I should say I am not a biologist, I just try to use my imagination to solve problems and this what it’s telling me about aging.

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