
Blocking a protein curbs memory loss in old mice: study - LinuxBender
https://med.stanford.edu/news/all-news/2019/05/blocking-protein-curbs-memory-loss-in-old-mice.html
======
hirundo
> Impeding VCAM1, a protein that tethers circulating immune cells to blood
> vessel walls, enabled old mice to perform as well on memory and learning
> tests as young mice ... it subdued the inflammatory mood of the brain’s
> resident immune cells

So this suggests: ↓ inflammation = ↑ memory. In the short term inflammation
generally impedes function, so this is an intuitively reasonable result.

~~~
pfd1986
Specially in light of recent correlations found between inflammation and all
sorts of diseases including neurodegenerative ones, previously discussed on
HN: [https://harvardmagazine.com/2019/05/inflammation-disease-
die...](https://harvardmagazine.com/2019/05/inflammation-disease-diet)

~~~
caprese
I always wonder if this is a design flaw, or if there is another completely
worse state that the body is trying to prevent happening, a state we don't
even know about until we have "cured" inflammation and all these other
diseases

sort of like how we wouldn't be studying a lot of this stuff right now if such
a large portion of the population hadn't gotten so old

~~~
duckduckcow
There's a lot of evidence suggesting that it's a feature rather than a bug.

There's lots of bad things that happens as you get older and upregulation of
inflammation plays an important part in that.

The thing is it's not random though. It happens in a synchronized fashion.

It does seem increasingly likely that our genetic code contains instructions
to make us increasingly frail and sick as we get older,to slowly increase the
probability of death.

We see this more clearly other places in nature. Closely related species that
have ended up in different environments over time can have dramatically
lifespans.

I have seen various hypotheses for this, including models that suggest that
there's a tendency for older individuals to keep too much of the resources so
that the younger generations won't have enough resources to grow and flourish.

~~~
wrinkl3
Or it could just be that there was never a lot of evolutionary pressure for
the "stay fit while old" traits. Being healthy for long enough to reproduce
and provide some care for your progeny was usually good enough from the
evolutionary standpoint, so the frailty-at-old-age genes weren't actively
selected against.

~~~
duckduckcow
It could be, though with a bit of Googling I found this blog post summarizing
scientific studies that suggest otherwise.

[https://joshmitteldorf.scienceblog.com/2016/05/16/no-
animal-...](https://joshmitteldorf.scienceblog.com/2016/05/16/no-animal-dies-
of-old-age-in-the-wild/)

------
RcouF1uZ4gsC
From [https://www.jax.org/news-and-insights/jax-
blog/2017/november...](https://www.jax.org/news-and-insights/jax-
blog/2017/november/when-are-mice-considered-old)

it appears that old mice are 18-24 months old. While mouse models in general
are hard to apply to humans, I would guess that applying "old" mouse models to
"old" humans is likely to be even harder.

------
leptoniscool
Are there any foods we can eat to lower inflammation in general?

~~~
bad_user
The study was done on mice and the metabolism of mice is different from ours.

In humans refined carbohydrates and hyper-processed food in general (which
includes hyper-processed meat) contributes the most to inflammation.

~~~
Aromasin
There's growing research to say that eating any meat (specifically red meat)
increases inflammation. Among other things, it elevates levels of C-Reactive
protein, which the liver makes when there is inflammation in the body.[1]

Another studied suggests that meat intake increases levels of arachidonic
acid, which is another mediator in inflammation and aging.[2]

Those are just a couple of studies. There are plenty more where they came
from. I highly suggest reading 'How Not to Die' by Dr. Michael Greger, to all
those that are interested in way of reducing inflammation in the body. The
book is incredibly well referenced, and a joy to read. [3]

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/24284436](https://www.ncbi.nlm.nih.gov/pubmed/24284436)

[2]
[https://www.ncbi.nlm.nih.gov/pubmed/28146136](https://www.ncbi.nlm.nih.gov/pubmed/28146136)

[3] [https://www.amazon.com/How-Not-Die-Discover-
Scientifically/d...](https://www.amazon.com/How-Not-Die-Discover-
Scientifically/dp/1250066115/&tag=httpwwwdrgreg-20?pldnSite=1)

~~~
bad_user
First of all, humans have been eating red meat for literally millions of
years.

Both those links are observational studies. The first link even admits that
the association is weak. And the second link is a population-level study.

Observational studies are important clues, but too weak to base conclusions
on, as in such studies it's hard to isolate the variables. For example given
that red meat has been a scare crow, you've got the "healthy user bias" [1],
in other words the people that tend to eat red meat are also those that tend
to engage in unhealthy activities like smoking, eating junk food or not
exercising. Scientists of course try to take such factors into account, but
that's really hard to do.

Also such science is reductionist because it uses markers that may or may not
have an impact on all cause mortality on or the quality of life, as such
markers need to be read in context (often in relation to other markers). And
since you mentioned "arachidonic acid", its rise isn't necessarily unhealthy.

Here's an article that debunks the notion that red meat is inflammatory:
[https://chriskresser.com/does-red-meat-cause-
inflammation/](https://chriskresser.com/does-red-meat-cause-inflammation/)

[1]
[https://en.wikipedia.org/wiki/Healthy_user_bias](https://en.wikipedia.org/wiki/Healthy_user_bias)

~~~
Aromasin
“For example, the traditional diet of the Masai was composed almost entirely
of red meat, blood, and milk – all high in Neu5Gc – yet they were free from
modern inflammatory diseases. (7)”

I get why people keep trying to fall back on Price’s research into the Masai,
but I’m afraid it’s misleading. The Masai actually had significant rates of
atherosclerosis, they just didn’t die from it, at least not the ones that
otherwise lived long enough to matter. [1] To say that article 'debunks' it is
disingenuous regardless. It is simply a counter-argument in article form; part
of a debate that could well be retorted by someone more intelligent than
myself (I'm sure Greger could give it a good rebuttal).

I think we can all agree that the best way to reduce inflammation is simply to
exercise. It's been shown time and time again. By using the Masai as an ideal,
we're simply looking at healthy user bias but in reverse. Justifying meat
consumption with a tribal population that often runs marathons to catch said
meat is baffling to me; it is not an excuse to dismiss a vast amount of
research, both observational and otherwise.

I've latched on to meat and its markers of inflammation because it's relevant
to the OP topic, but if we're going down the route of history, really we
should be basing diet on our genetic biomarkers. "First of all, humans have
been eating red meat for literally millions of years." should really be "First
of all, small populations of certain humans have been eating red meat for
literally millions of years." From my studies on ancestral human eating
patterns, it seems that most were almost entirely vegetarian, and may have
only eaten meat during celebrations a few times in a year. Scientific American
had a great article on the topic [3].

To quote a favoured read of mine, "Human gene variants promoting veggie-rich
and meat-rich diets are still distributed among modern humans. They fall into
patterns one might expect given modern cultural dietary traditions. A gene
variant that promotes conversion from plant based dietary food sources to
omega 3 and 6 fats necessary for brain development is found more often in
India, where many people are vegetarian. A different variant that slows this
conversion is found among arctic people who eat a fish-heavy diet already very
rich in these fats, according to a recent Cornell study." [2] This is why
nutrition science is so difficult. However, I still believe that with the
modern human exercising a little as we do - even 2 hours 7 days a week, a
massive amount to us now unless you're an athlete, is very little compared to
our meat eating ancestors - that a need for a plant based diet is higher than
ever, and that applies to everyone.

[1]
[http://aje.oxfordjournals.org/content/95/1/26.abstract](http://aje.oxfordjournals.org/content/95/1/26.abstract)

[2] [https://geneticliteracyproject.org/2018/03/30/why-humans-
sta...](https://geneticliteracyproject.org/2018/03/30/why-humans-started-
eating-meat-critical-diet/)

[3] [https://blogs.scientificamerican.com/guest-blog/human-
ancest...](https://blogs.scientificamerican.com/guest-blog/human-ancestors-
were-nearly-all-vegetarians/)

~~~
bad_user
> " _the best way to reduce inflammation is simply to exercise_ "

Exercise helps, but the evidence for it is mixed. I don't think there's any
amount of exercise you can do to undo the damage of a toxic diet, which the
standard diet tends to be.

And as proof there are professional athletes that end up suffering from
chronic illness and inflammation. Even more so, intense training like for
running marathons can make you sick, because it can lead to a suppression of
the immune system due to the stress involved [1]. On a cursory search I found
a meta-analysis on studies on the effects of marathon running on inflammation
markers and the results are very mixed, endurance running promoting both anti-
and pro- inflammatory markers. [2]

Therefore your claim doesn't stand to scrutiny, even though we can agree that
exercise is mandatory for being healthy in general.

\---

> " _Justifying meat consumption with a tribal population that often runs
> marathons to catch said meat is baffling to me._ "

In your original comment you pointed at a population-level study (your second
link). Why is mentioning a study on an indigenous population any less valid?
Is that a double standard I'm sensing?

We study indigenous populations because chronic diseases are very modern and
it has something to do with the modern environment, which includes the diet,
especially since many of these populations got sick after being transitioned
to the western diet.

The Masai might have been exercising more and live with less stress, which
might have contributed to their overall health, or maybe they ate that meat
with something else that reduced the inflammation, however this is an
admission that context matters and that reductionist statements such as " _red
meat is inflammatory_ " are wrong.

Also apparently we burn as many calories as hunter gatherers [3], so I would
be careful about such statements.

\---

> _" From my studies on ancestral human eating patterns, it seems that most
> were almost entirely vegetarian, and may have only eaten meat during
> celebrations a few times in a year."_

The article you linked to is entirely devoid of any tangible proof and given
the editorial style I can't take it seriously.

Indeed, the diet of apes and monkeys is composed of leaves, nuts, fruits and
insects. However this is a very bizarre argument. Us becoming omnivores and
starting to hunt animals and eat meat is what allowed us to adapt to harsher
environments and to grow our big brains. Eating meat is what made us human and
what drove us to develop tools made of stone for hunting or for collecting the
bone marrow, it's what drove us to use fire for cooking, in order to increase
the bio-availability of the meat and the starches that we eat.

First of all because our big brain can only be explained by the availability
of high-calorie foods. High-calorie foods are not very available in nature in
edible form. We couldn't have digested many of the high-calorie starchy plants
that were available. The prevailing theory is that fire was first used for
cooking in order to cook starchy plants that were toxic otherwise. But the
first known use of fire was only 1 million years ago [4] and does not coincide
with the expansion of our brains.

Use of stone tools however coincides with the expansion of our brains, yet
routine use of fire may have began only 300,000 years ago [5], which means
starchy plants weren't very available for us to eat, certainly not enough to
explain our high-caloric diet.

The best indications for what our ancestors ate comes from looking at modern
hunter-gatherers and we've got plenty of such populations observed [6].

Observed hunter-gatherers obtain most of their energy from animal foods [7].
From the groups studied in that reference, they found ...

\- 46 groups that obtained 85% of their energy from meat, fish and eggs (with
no groups obtaining this much energy from plants)

\- 133 groups that obtained 65% of their energy from meat, fish and eggs (only
8 groups that obtained 65% of their energy from plants)

\- the median average obtained 70% of their energy from animal sources, 30%
from plants

Note that this report has been criticized to have some flaws, but there is a
substantial body of evidence for the theory that, on average, hunter-gatherers
got 70% of energy from animals [8] [9] [10].

\---

[1] [https://www.theguardian.com/lifeandstyle/the-running-
blog/20...](https://www.theguardian.com/lifeandstyle/the-running-
blog/2015/aug/27/the-elite-athlete-paradox-how-running-a-marathon-can-make-
you-ill)

[2]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5650970/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5650970/)

[3]
[https://journals.plos.org/plosone/article?id=10.1371/journal...](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0040503)

[4]
[https://www.pnas.org/content/109/20/E1215](https://www.pnas.org/content/109/20/E1215)

[5]
[https://www.pnas.org/content/108/13/5209](https://www.pnas.org/content/108/13/5209)

[6]
[http://eclectic.ss.uci.edu/~drwhite/worldcul/10-2gray.pdf](http://eclectic.ss.uci.edu/~drwhite/worldcul/10-2gray.pdf)

[7]
[https://www.ncbi.nlm.nih.gov/pubmed/10702160](https://www.ncbi.nlm.nih.gov/pubmed/10702160)

[8] Cordain, L. “Implications of Plio-Pleistocene Hominin Diets for Modern
Humans,” pp 363-383 in Peter S. Ungar, ed., Evolution of the human diet: the
known, the unknown, and the unknowable, New York: Oxford University Press,
2006.

[9]
[https://www.ncbi.nlm.nih.gov/pubmed/10702160?dopt=AbstractPl...](https://www.ncbi.nlm.nih.gov/pubmed/10702160?dopt=AbstractPlus)

[10]
[https://www.unm.edu/~hkaplan/KaplanHillLancasterHurtado_2000...](https://www.unm.edu/~hkaplan/KaplanHillLancasterHurtado_2000_LHEvolution.pdf)

------
jonhendry18
Before people start eating extreme low protein diets, that should be "Blocking
_a_ protein".

~~~
thrower123
Also, there is the whole "in mice" bit.

One of the more valuable science twitter accounts to follow is the one that
that just retweets every sensationally misleading pop-sci headline that ends
up being based on rodent studies with an all-caps IN MICE! comment.

~~~
pazimzadeh
Trendy, yes. Valuable, not sure. Maybe to keep track of the bleeding edge of
basic research. This is much better news than the headline "Nothing we do
seems to affect memory loss in mice." It means we're starting to understand
how memory works at a molecular level in mammals.

~~~
thrower123
Right, it's good that we have the very beginnings of an understanding of how
the process might work. In mice. Applications to humans are, if previous track
records are anything to go on, five to twenty years out and uncertain.

Meanwhile, gullible people with poor reading comprehension will see the
headline, or hear the badly interpreted third-hand reporting on the study
during the science puff piece section of the nightly news. Some fraction of
the hypochondriatic will take it up as gospel, and begin preaching it, and the
sum total is a contribution to the mountain of medical misinformation that is
floating around in the popular consciousness.

