Slashdot Mirror
Scientists Have Mathematical Proof That It's Impossible To Stop Aging (sciencealert.com)
An anonymous reader quotes a report from Science Alert: Mathematically speaking, multicellular organisms like us will always have to deal with a cellular competition where only one side will win. And ultimately, that means our vitality will always come out as the loser. We have a pair of researchers from the University of Arizona to blame for this depressing conclusion, who crunched the numbers on a hypothesis involving the weeding out of unfit cells and found it amounted to a catch-22 situation. Aging -- and all of the biological changes that come with it -- is more or less the result of cells slowing down and losing their functions. But what if there was a way to encourage the more active cells to stick around at the expense of their sluggish siblings? Surely if we knocked off those old cells we could keep making pigments and collagen a little longer. Researchers have pinned hopes on reversing the inevitable decay of biochemistry by repairing DNA or extending the shrinking bits of chromosome called telomeres, for example. While it's good in theory, there is a catch. Another feature of aging is a number of cells start to populate like there's no tomorrow, reproducing in uncontrolled ways that look too close to cancer for comfort. According to the researchers, this means we're damned either way.
The way we grow old poses something of a mystery. If replicating biology is good enough to continue for generations, why do our own cells wind down after just a few decades? A simple answer is evolution isn't strong enough to weed out genes that only cause us grief after we've popped out a few offspring. But this model of aging adds a new element to the existing hypothesis -- even if evolution did select for eternal youth, competition inside our own bodies would see us to an inevitable grave. In other words, since multicellular organisms are the cumulative effect of bunches of cooperating cells, we logically can't have it both ways -- if you clear the way for 'younger' cells to keep your skin baby-smooth, you're just asking for the big C. The findings have been published in the journal Proceedings of the National Academy of Sciences.
The way we grow old poses something of a mystery. If replicating biology is good enough to continue for generations, why do our own cells wind down after just a few decades? A simple answer is evolution isn't strong enough to weed out genes that only cause us grief after we've popped out a few offspring. But this model of aging adds a new element to the existing hypothesis -- even if evolution did select for eternal youth, competition inside our own bodies would see us to an inevitable grave. In other words, since multicellular organisms are the cumulative effect of bunches of cooperating cells, we logically can't have it both ways -- if you clear the way for 'younger' cells to keep your skin baby-smooth, you're just asking for the big C. The findings have been published in the journal Proceedings of the National Academy of Sciences.
Ok. I'm a mathematician, so I think I have some degree of expertise relevant to comment when someone says that they have a mathematical proof of something. You cannot give a mathematical proof of something in the physical world. At most, you can give a mathematical proof that something is true in some model of the physical world. Your model may or may not match expectations. This occurs all the time; there are all sorts of proofs of security in cryptography (generally assuming certain computational complexity assumptions) and yet the crypto systems are frequently broken by using clever side-channel attacks or other clever tricks that couldn't be done in the context of the model of computation being used. In this case the fact that some other species can live much longer than humans is by itself a pretty big sign that the model is by far from a perfect one. And from glancing at the article in question, it looks like the scientists actually didn't claim nearly as big a deal as the summary suggests.
So it's either aging or cancer? I don't buy it. Someone in their teens isn't aging (in way we're all talking about it), quite the opposite. But neither is their rapid renewal of useful stuff like cartilage, collagen, etc., blowing up as cancer for all of them. This mathematical proof that you can't have it both ways is based on a premise of there only being two ways. Something as complicated as a mammal body never operates in a one-way-or-another set of only two possibilities. We're the sum of many, many processes. There's room to tweak the nature and damage of aging skin, joints, brains, and hearts and thus mitigate some of the hardships of aging without assuming that it's only successful if we become beautiful young immortals.
Don't disappoint your bird dog. Go to the range.
I remember for years the phrase was "mathematically a bumblebee can't fly". I hardly think we know all the nuances of cellular mechanics yet.
This is why we don't invite mathematicians to parties.
These guys have absolutely no clue what the hell they're on about. They start out grossly misunderstanding how aging works and what its role in biology is, then go on to grossly misunderstand how cancer is generated. Then they grossly misunderstand how replication works, followed by grossly misunderstanding evolution (strong enough? Who at a university+ level would say something like that?).
Any freshman biologist can answer all these questions easily.
Aging is the result of a) your body adapting to its current needs (growing, reproduction etc) and b) your genetic material accumulating errors from the replication used to build new cells. This is not a theory, this is not "controversial", this has been the settled conclusion for a long time. If the mathematicians at Arizona can't pick up a textbook...
The carcinogenesis process is also well understood (though there are many details, such as the newfound roles of both micro- and lnc- RNA, that are still a mystery).
There are X number of established ways, all involving knocking out tumor-preventing pathways or hyper-activating growth pathways. It is not a result of aging, but of the previously mentioned genetic errors that come with replication + plus external factors that may play some role (infection with HR-HPV is considered a requirement for cervical cancer, and plays a major role in some other cancers including penile, vulvar, anal, head, and neck). If it were a result of aging, or if cells got "hyper-competitive" later down the road, we wouldn't see kids with leukemia, nor teenagers with melanoma (from tanning all day long, something that causes massive buildup of genetic errors in the skin cells).
Our cells never actually wind down. They do the best they can with the resources they are given. As our machinery accrues more and more faults over the years, the functionality deteriorates. Just like an 8 year old computer will have some problems and some 'ticks', so too will cells based on old DNA. But there is no in-built wind-down parameter, there is no "give-up and die" gene.
At most we have something called telomeres attached to our chromosomes that tells us how many times the chromosome has been replicated, giving an indicator of how "reliable" the chromosome DNA is. Extending the telomeres leads them to be used for longer. This allows more errors to accrue in the chromosome, which increases the risk of a cancer blocking pathway on the chromosome to be knocked out. Hence, if you want to live forever, you have to both extend the telomere as well as prevent replication errors.
And to answer the final (ridiculous) assertion -
But this model of aging adds a new element to the existing hypothesis -- even if evolution did select for eternal youth, competition inside our own bodies would see us to an inevitable grave. /quote
There is only "competition" inside the body when something has already gone horribly wrong. There are more than 10 "anti-compete clause" pathways active in each cell. If a cell "competes", it will receive an apoptosis signal to commit suicide, and it will be destroyed by the body's own immune system. It is only when these anti-compete pathways have been destroyed already that any classic evolution-based competition can occur.
In short, these guys really should have asked a biologist before spouting nonsense.
I get what you are saying, but to think like that in absolute terms is to ignore the billions of positive selfless acts that also happen each day among humanity.
Our civilization could not exist in the complex way it does without MOST members of the race USUALLY behaving in ways that involve friendship, love, kindness, and selflessness.
We all have a selfish animal side existing inside of us. But we also have the thinking side that has allowed humanity as a whole to continue on despite the animal side.
I believe the next 100 years will be absolute critical on if our path as a race leads us as a race toward extinction or some kind of 'beyond physical body' immortality.
Sure, it sounds like it, because they oversimplified the problem. One issue with engineering education is that in order to make problems solvable, they teach you to make a lot of assumptions to simplify the problem. It's a useful tool for making control systems on a small scale, but for more complex systems like biology(even single celled organisms), politics, economics, weather, climate, psychology, it doesn't work. I think this disconnect leads to a lot of arrogance(I myself had to learn the hard way) about what we have the ability to control or even predict. I think this arrogance, the over simplification of complexity, is largely why engineers tend to be the most likely candidates for terrorism. They have immense power to understand and control simply systems, so why not big complex systems too? https://www.washingtonpost.com/news/monkey-cage/wp/2015/11/17/this-is-the-group-thats-surprisingly-prone-to-violent-extremism/
Making an absolute claim like this is always a great way to make yourself look stupid.
Which is why you only find this claim in the shit journalism that's trying to pander to a mainstream audience and not in the paper itself. I really wish I had millions of dollars, because I'd buy /., hire some competent people, and go right to the actual research rater than the sensational, misleading bullshit that is used to get ad-views.
Velociraptor = Distiraptor / Timeraptor
Well there's always analogies.
With humans, the analogy is to both a computer and to virus itself.
The more the cells replicate, the more they have to compete for resources, thus they will always reach a tipping point where there is a population crash. That is what "aging" is. There are too many cells in the body that competition among them results in unbalanced resources, and the body starts destroying cells in a desperate attempt to stave off the inevitable.
Take grey hair as an example. Grey hair is the result of bubbles being introduced into the hair strands as pigments stop being produced.
Obesity is another, the body has so many cells that it doesn't know to destroy the fat cells and not, say heart or muscle tissue.
If you were to be able to rewind the telomeres, what would inevitably happen is that the cells would continue to divide, regardless of errors, to the point that they starve. This is why Cancer happens. Those are cells where the "stop and die" function has been disabled.
When you lose weight, the body doesn't know what cells to burn. When you eat too much protein, the body doesn't know if it should be burned before burning muscle when starving.
Hence your body has a natural balancing mechanic, and when you force something out of balance, it compensates, in often unpredictable ways. People who get cancer, near universally have some bad habit that could be pinned on it before you could point to genetic factors.
Sugar and artificial sweeteners are very likely at the top of the bad habit list, right after alcohol and smoking as "likely the reason your body started producing cancer cells"
Yes correct. Moreover they have misunderstood their own math. It doesn't say that aging cannot be repaired. It said that evolution cannot do it. There is no organism that lays spare parts in cold storage and then swaps them out when parts wear out. We however could eventually make spare parts.