Eating sea squirts may reverse the signs of ageing in mice: study | Hacker News Reader

Eating sea squirts may reverse the signs of ageing in mice: study

xjtlu.edu.cn

44 pointsgnicholas47 comments

A single fully inbred strain of mouse was used in this study—C57BL/6J. And only females. This is as if the FDA tested a drug in one human and then said—“Good to go.” Ridiculous.

Please before you recommend these studies to HN look at the methods section and evaluate the animal model. Any study using only one type of mouse or rat is just a pretty Potemkin village. Results are neither robust within the species nor are the translatable to humans.

When our group studies longevity and diet in mice we use 40 to 80 different types of mice.

See SR Roy, EG Williams, RW Williams, DG Ashbrook, K Mozhui 2021 in Nature Metabolism, Cell Systems, Aging Cell, eLife and bioRxiv for examples of how it should be done.

How reasonable is it to do preliminary studies with a single strain? I honestly don't know the pros/cons of doing so.

Seems like it'd be ideal to just work with a single strain; you'd rule out many confounding factors. I don't see why having multiple different strains of mouse would make the results more generalisable to humans.

It's still a controlled trial with some compelling results and analysis. This is an excellent basis for further research.

> Please before you recommend these studies to HN look at the methods section and evaluate the animal model.

I wouldn’t be surprised if a significant portion of such HN submissions are done for the precise purpose of getting appraisals of this sort from knowledgable HN readers.

Scientist: "Hey, that's interesting"

HN: "In mice! Move along, nothing to see here!"

Belonging to the former.

Fine here's 3 years to prove it on 0.25FTE... next paper please.

Your comment is itself ridiculous.

Do you expect them to go directly to clinical trials with no preliminary research? Of course not. This is exploratory research, not medical advice.

Seems like GP's clear point was to "use 40 to 80 different types of mice."

And isn’t reading about interesting exploratory research one of the reasons many people come to HN? I know I enjoy these articles.

I also enjoy these articles, but many come to HN to criticize things so they can appear smart.

It's not working for them.

Great so why is exploritory stuff being published without being completed? This isn't a known to work vaccine or equivalent.

If for no other reason, then it's useful to others who would attempt this same research in the future who no longer need to. But aside from that, it establishes a potential path to increase our knowledge of the relationship between sea squirts and aging. It gives other researchers something to build upon.

Just out of curiosity, are you a vegan?

OP here; sorry for not vetting the study. I am not a scientist, so all I did was check to see if there had been any discussion of this therapeutic on HN. I’m glad there are folks like you who can easily provide critiques on the study/methodology!

From https://en.wikipedia.org/wiki/Ascidiacea#Uses

> When served raw, they have a chewy texture and peculiar flavor likened to "rubber dipped in ammonia"

Sea squirt is the single thing I had on a trip to Korea that I didn't enjoy. This description is bang on.

First: in mice.

The next thought that immediately comes to mind is, if it's an edible animal that's been available possibly for centuries, then probably people would have noticed something before. If _any_ well-known ingredient _substantially_ increased lifespan [edit: or keep you younger] by just eating it, we'd know about it for a while now.

I don't think I really agree with the conclusion that we would notice that. Lifespans and aging are long-term things and the average person has been eating a lot of different things, everyone has stories of the smoker or drinker who lived til 90 and the healthy one who lived til 65 - the amount of confounding variables is very obfuscating, not to mention the massive presumed role of genetics

Additionally, I would guess this isn't a well-known animal, a different comment from user "evdubs" [0] pointed out:

> When served raw, they have a chewy texture and peculiar flavor likened to "rubber dipped in ammonia"

[0]: https://news.ycombinator.com/item?id=31634129

Korea and Japan, where these are eaten, are 2 of the top 3 countries for life expectancy.

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

Man I have a feeling it will be hard to find these where I live, but I'll give it a go.

The mice were fed supplements so it would seem that eating the real thing isn't necessary at least if you're a mouse.

A lot of stuff that works on mice doesn’t work on humans. I’m surprised this made it to the front page.

I read this a lot. But I've also read the opposite: that it's hard to find effects demonstrated in smaller mammals that don't also hold in humans.

What are examples of findings from mice that haven't held up in human populations?

Resveratrol? That was supposed to be a big fountain of youth, but has flopped spectacularly.

Often drug studies, such as in the case of Fialuridine. Showed excellent results in animal studies (including mice, rats, dogs, and primates) with no ill effects, but ended up being fatally toxic for humans. Turned out it was toxic in humans because a specific protein on the surface of our mitochondria would move it inside our mitochondria, where it would poison/destroy our mitochondria. This didn't happen in the animal studies (even though they have the same protein), because 3 DNA mutations caused the gene encoding the protein to be just different enough, that it would prevent it from being able to transport the drug into their cell’s mitochondria.

Now that said, just because one promising animal study failed to work for humans, doesn't mean they all will fail. A lot of animal studies do in fact also hold for humans. It's just that, one shouldn't jump to conclusions either which way.

Piure is relatively popular in Chile.

https://en.m.wikipedia.org/wiki/Pyura_chilensis

I have had it, and it is delicious.

Chile’s local seafood in general is great (https://en.m.wikipedia.org/wiki/Austromegabalanus_psittacus is great) - it’s unfortunate it’s not more popular in the country itself.

Is this the same animal? If so we can take this as disproven as Chileans don't look younger than other people :)

It’s in Ascidiacea - so yeah.

Maybe counterbalanced by all the smoking and hot dogs though

Personally I think the whole idea that one particular compound reverses aging is impossible. And just wishful thinking (or outright scam).

Aging is so deeply ingrained in the process that created our DNA. Without aging, evolution is completely broken. So it makes sense that it's extremely hard to 'turn off'. There's also no species that doesn't age AFAIK, and no compound found in nature that reverses aging for any species.

I'm sure we will eventually manage to figure it out but it'll be a lot more involved than eating a particular kind of sea critter.

Those poor creatures: unless can synthesize the active ingredients, they will harvested to their end.

Or they'll be domesticated.

And they will be if it's feasible and there is a demand. I wonder how difficult it would be to farm-raise them. We do it with many varieties of fish.

This was my first thought as well. As soon as the supplements industry gets hold of this info...so long sea squirts.

Hello huge tanks raising sea squirts in easy to harvest conditions.

There are already plasmalogen supplements on the market.

There is no compound in nature that we cannot synthesize in a lab, but sometimes it is more expensive than harvesting it from plants/animals.

Animals with economic value rarely go extinct. Just look at cows, pigs, and chickens.

It’s the ones that don’t have value that are at risk.

> Animals with economic value rarely go extinct

What about mammoth, passenger pidgeon, great auk, quagga, parakeet, shark, horseshoe crab, tuna, whale ... the list goes on and on

I’m guessing if you’re allergic to chitin you can’t do this? Anaphylactic shock isn’t worth a slightly larger working memory ahahaha.

Anaphylactic shock does tend to keep you from growing old.

Think I'll pass given the high claim and frankly single study. Not sure I'd call myself an expert but given this is on a uni page and not nature.com I think it's very easy to criticize this as probably not standing up to too much as of yet.

It's weird how often people read a headline and interpret "may reverse signs of aging" as "go out right and much on the sand-gummies, you'll definitely live forever." Headlines are bollox, lay-articles are little better, and journal articles tend to be truthy in their claims (but are occasionally total fabrications). Re-calibrate your expectations.

> journal articles tend to be truthy in their claims

The replication crisis (aka replicability crisis or the reproducibility crisis) says you really really shouldn’t trust most journal articles.

I said truthy, not truthful. They're often fairly accurate reports about what they did/recorded (I said "often," mind, not always -- p-hacking is a common lie of omission). That doesn't mean they're accurate predictions about future results, as studies are extremely limited in their scope, size, control, etc., which is one of two factors behind the replication crisis. The other factor being that replication studies are rare.

When I read headlines/articles like this, I think "oh neat, I wonder if somebody will identify the mechanism behind some mystery protein acting on whatever system in mice, and if that interaction has an analogue in humans." People on HN frequently seem to be enraged rather than curious about studies with overblown headlines, and it's a little sad.

1. Bio article

2. Peer review not done for local web publish

3. Not going to over-emphisize but the research "centres of excellence" aren't Oxford or Harvard here

4. The reproducibility crisis in bio

5. It's clearly trying to get more attention than it's worth. Unless I recalibrate my expectations of reality (yes I work in research as a published professional) it's bad. (Eg this is defending publications of "Highs signal at 110GeV" from the tevatron as being worth reading in the 00's. It's clearly biased as we now know it couldn't have happened)

6. I'm not sure how we get from my comment of 1 study to there being no obesity epidemic in burgerland. Please stop reading vitriol into my comments.

Your comment is one of several on this article. Some enraged/dismissive, some overly credulous. It's the lack of curiousity I find disappointing.

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