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Cells across the body talk to each other about aging

quantamagazine.org

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

#121

Post by mlyle »

omeid2 wrote: post #100
mlyle wrote: post #97

Earlier quoted context omitted.

Yah, I don't think it's the loss of information, but a related concept: it's a decline in order. We have a whole lot of redundancy and mechanisms to restore/repair redundancy. But even so, there's a march of entropy upwards; oxidation, genetic damage, cell death, tissue damage, neuron loss, etc. We don't have repair mechanisms for everything the body knows how to build, and the repair mechanisms that we do have becom…

> it's a decline in order. That is another way of saying loss of information and increase of entropy.

While the thermodynamic and the information theoretic concepts of entropy are related, it's not really applicable here. All the "real" information in the system is highly redundant (except perhaps neurological)-- we have billions of copies of the "information". The system's ability to restore itself to the order specified in the plan is lacking.

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

#122

Post by speedylight »

omeid2 wrote: post #91
speedylight wrote: post #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 be…

> 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.

I assume by information you’re referring to DNA? If so we can already sequence human DNA from all sorts of samples (so for example we store a copy of it from a young age, like 20), the hard part would be replacing the damaged DNA with the undamaged copy, in every cell of the body—sort of like reinstalling an operating system.

It’s interesting to think about the implications of such a technology, if we can swap DNA with another, fresher copy, we should also be able to modify it and make the body do things it wasn’t previously capable of doing. One idea that comes to mind is expanding the range of our senses, or giving our body a better system to repair and regenerate itself beyond what we naturally evolved to able to do so we can have longer life spans with a quality of life that makes it worth it.

It sounds like a bad idea to play god like this, and it probably is, but we’ll never know until we give it a serious try. I remember a while ago a scientist in China modified the DNA of human embryos by using Crispr, the goal was to make them resistant to HIV infection and he was jailed and ridiculed for it.

The search space for new and improved capabilities is endless once we learn how to program DNA like a computer. We are probably at least a century away from this level of control, and probably another century before it becomes socially acceptable to do it at scale.

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

#123

Post by speedylight »

verelo wrote: post #103
omeid2 wrote: post #98

Earlier quoted context omitted.

Substitution isn't reversal.

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.

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

#125

Post by yterdy »

fsckboy wrote: post #106
wegfawefgawefg wrote: post #83

Earlier quoted context omitted.

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…

> 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 to ferry. In reality, the system is complex, incentives and drives are many; a holistic view is more useful than forcing a tortured atomic hierarchy onto that system.

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

#126

Post by grishka »

This seems to fit nicely with the other research that explores the rejuvenation effects of "young blood", but specifically purified and concentrated extracellular vesicles. Harold Katcher's research especially — except he doesn't yet know what it is exactly in those EVs that triggers the effect he observed in rats.

Here's one of those papers: https://www.biorxiv.org/content/10.1101/2023.08.06.552148v1....

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

#127

Post by qp11 »

aeternum wrote: post #82
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…

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?

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

#128

Post by qp11 »

LASR wrote: post #3

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…

Same reason everything doesn't turn into a predator or a parasite. We get ecosystem collapse as soon as that happens.

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

#129

Post by yarg »

wcoenen wrote: post #64
yarg wrote: 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…

The survival of the individual is exactly what is being selected for. The influence of an individual gene is not distinguishable from those that are packaged with it.

So what is selected for over any single cycle is sets of sets of genes conveying advantage.

Taking half of your genes from each parent could only select whole useful chromosomes from each parent (but is far better than nothing);

In order for genes to be selected in their own rights, you need more.

Chromosomal crossover copies genes across chromosome pairs - over the course of repeated iterations this allows useful mutations to be more easily distinguished.

https://en.wikipedia.org/wiki/Chromosomal_crossover

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

#130

Post by yarg »

wegfawefgawefg wrote: post #83
wcoenen wrote: post #64

Earlier quoted context omitted.

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…

The individual capable of survival is what survives - he brings with him the genes that conveyed his advantages.
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