Serotonin! More than a neurotransmitter.

May 3, 2011 1:56 PM

Serotonin is back in the news. Recent research shows that it plays an impressive number of roles throughout the body, both below the neck and above it.

It isn't just a neurotransmitter anymore. Now it's also a hormone synthesized in the gut that (would you believe?) regulates bone construction. It's supplied by the placenta (thanks, Mom!) to a human embryo, where it stimulates new neural connections. It's also important to wasps and sea urchins.

posted by exphysicist345 (34 comments total)

Recent research shows that it plays an impressive number of roles throughout the body, both below the neck and above it.

Hm. So does my tongue.
posted by Astro Zombie at 1:57 PM on May 3, 2011 [24 favorites]

I don't care how important it is to them, wasps and sea urchins better stay the hell away from my serotonin.
posted by theodolite at 1:58 PM on May 3, 2011 [8 favorites]

Hm. So does my tongue.

ZING
posted by thsmchnekllsfascists at 1:59 PM on May 3, 2011 [2 favorites]

It sounds like limiting gut serotonin would reduce osteoclasts and stop bone loss. I wonder if this will become a treatment for osteoporosis? I would like to rely on having strong bones when I'm old.
posted by cereselle at 2:08 PM on May 3, 2011 [1 favorite]

Hm. So does my tongue.

ZING

More like SLURP
posted by doublehappy at 2:10 PM on May 3, 2011 [1 favorite]

Ok, I seriously couldn't make it through the first few paragraphs. This author needs to stop with their own verbal cleverness. Seriously.
posted by strixus at 2:11 PM on May 3, 2011 [1 favorite]

Just when you thought that serotonin was passé, and you’d tossed all your half-used bottles of S.S.R.I.-type antidepressants because the ones that didn’t give you nausea or smother your libido left you wondering whether you were in the placebo arm of a clinical trial,

I love the NYT.

1) We were all on S.S.R.Is
2) Gave them up because we thought serotonin was passé, just like brunch at Pastis.
posted by Ad hominem at 2:14 PM on May 3, 2011 [33 favorites]

If I hear about serotonin doing more, then makes me feel even more afraid about messing with the body's levels.

That said, SSRIs help a lot of people, even if they aren't a magic bullet. Hopefully we'll come up with something better.
posted by mccarty.tim at 2:15 PM on May 3, 2011 [1 favorite]

Strixus, it gets worse. I made it to the second page but couldn't get through the whole article. Since when does the NYT allow its writers to try out their amateur comedy in the paper?

...and bananas, a fruit that, despite its notorious comedic associations, always ends up on lists of “very wholesome foods with possible medicinal value.
posted by tempythethird at 2:15 PM on May 3, 2011 [1 favorite]

I'd just re-kajiggered the molecular model on my nightstand from serotonin to dopamine. Can anyone tell me if I should now swap back?
posted by Earthtopus at 2:38 PM on May 3, 2011

I'd just re-kajiggered the molecular model on my nightstand from serotonin to dopamine. Can anyone tell me if I should now swap back?

I heard about this awesome new neurotransmitter, It's in Brooklyn.
posted by Ad hominem at 2:45 PM on May 3, 2011 [8 favorites]

Also, upon reading the article, HA HA JOKE ABOUT HIPPIE ACID BURNOUTS alert.
posted by Earthtopus at 2:46 PM on May 3, 2011

The latest findings may never lead to a satisfying pharmacologic fix for what the psychiatrist Kay Redfield Jamison has called “ordinary existential angst” and others “terminal you-ness,”

Weird. Am I reading the NYTimes or erowid? We already have drugs like that, but they're all illegal.
posted by delmoi at 3:01 PM on May 3, 2011 [4 favorites]

Serotonin is as close to Stalinism as you can get as far as neurotransmitters go.
posted by lore at 3:05 PM on May 3, 2011

If we ever get around to re-engineering the human body, one of the overarching themes will be the decoupling of systems. With genes and hormones doing double (and triple, and quadruple) duty, when problems arise, one is faced with solutions which only cause havoc elsewhere. Damned if you do, damned if you don't.
posted by adipocere at 3:07 PM on May 3, 2011 [2 favorites]

one of the overarching themes will be the decoupling of systems

I'd be interested to see these decoupled systems you talk about. My experience is that weird couplings and double duty arise in most complex systems, from automotive to computational. Taking apart a carburetor (fuel injection is worse in some ways) or hacking the linux kernel will tell you that.
posted by poe at 3:36 PM on May 3, 2011 [1 favorite]

Or even that NOVA episode about the tame foxes. It's fascinating how, without changing the genome at all, the hand-raising of some animals changes the way they develop across time, with different hormone-releases (or whatever) affecting the physical and emotional expression of the animal.

Complex systems are complex. I'm not sure that we'll be able to decouple as easily as simply isolating this and having it happen separately. Which is partially what adipocere is saying, and part of the deep complications which belie the concept adipocere is hoping to espouse.
posted by hippybear at 3:51 PM on May 3, 2011

they soon learned that the recently invented hallucinogenic drug lysergic acid diethylamide worked by tapping into the brain’s serotonin system

Huh, I didn't know that. Perhaps I owe MDMA an apology, and should be giving LSD a stern talking to.
posted by jack_mo at 4:03 PM on May 3, 2011

Recommended listening while reading this thread
posted by mannequito at 4:03 PM on May 3, 2011

No cites (no time to dig them up), but I've seen other papers that indicate serotonin as implicated in repair of gut lining and connective tissue.

Also, I've encountered individuals who have shown positive results on as little as 1 (one) milligram of fluoxetine (Prozac), with "positive results" being significant relief from panic attacks and general anxiety. (One caution: see your doc, *and*, if you do move into drug therapy it's almost always wise to accompany that with therapy, like cognitive therapy; there's good research to back this up.

Also, for those who claim that they would "never to SSRI's", those are probably individuals who have never suffered from the disabilities caused by acute depression, anxiety, panic, dysthymia, and so on. It's a tough row to hoe, and not everyone is up to it without pharmacological intervention.
posted by Vibrissae at 4:15 PM on May 3, 2011 [7 favorites]

Also, for those who claim that they would "never to SSRI's", those are probably individuals who have never suffered from the disabilities caused by acute depression, anxiety, panic, dysthymia, and so on. It's a tough row to hoe, and not everyone is up to it without pharmacological intervention.

Hear, hear. I hoed that row for 20 years because I didn't know what the hell was wrong with me, and my doctors dismissed my concerns. It was really difficult to put on a brave face and pretend I was "fine", when really, I wasn't.

Then I got a new doc, he listened, and suggested we try an SSRI to try to get me sorted out. Thing's a godsdamned miracle. I know they're not for everyone, but mine has made a huge difference in my quality of life.
posted by MissySedai at 4:43 PM on May 3, 2011 [4 favorites]

Natalie Angier, the writer of this piece, is well known for her flamboyant prose. Oddly enough, however, the SSRI's probably don't work by raising serotonin levels. They do that within hours but don't have real antidepressant effects for at least a week in most cases.

Like all antidepressants (including ECT and probably talk), they ultimately raise levels of nerve growth factors that increase repair and even creation of new cells in the hippocampus. Not coincidentally, high levels of stress damage this region and can cause depression.

Repair here seems to be a final common pathway for most antidepressant effects and explains why drugs that work on serotonin, norepinephrine, dopamine, etc. can all lift depression but they all take a few weeks (the time it takes for this regrowth to occur) to take effect.

Ketamine, which lifts depression in hours, seems to throw a monkey wrench in this idea, but apparently it may essentially mimic the end result of nerve growth and its effect doesn't last, suggesting that for lasting AD effect, you do need nerve growth.
posted by Maias at 4:48 PM on May 3, 2011 [7 favorites]

Repair here seems to be a final common pathway for most antidepressant effects and explains why drugs that work on serotonin, norepinephrine, dopamine, etc. can all lift depression but they all take a few weeks (the time it takes for this regrowth to occur) to take effect.


Maias, that's really interesting. Is there any literature discussing the possible ramifications of this theory? I'm no scientist but the theory would seem to suggest that at least *some* people would not need to remain on antidepressants for very long periods of time in order to achieve and maintain improved moods. That is, that they could actually go off the meds once the repair is effected (barring new stresses that inflicted new damage).
posted by artemisia at 6:09 PM on May 3, 2011

With all due respect, I don't think Maias is correct about how SSRIs work. They take time because depression isn't just an organic disease, and isn't the same for everyone. The nerve growth that is purportedly seen can just as easily be explained as the patient re-learning that life doesn't suck.

The bigger problem is having *enough* seratonin. [Do not] try taking 25mg of 5-HTP while on Zoloft. Instant happy followed by awful crash. (That's what your MDMA does, except it doesn't produce serotonin, it just forces the vesicles to squirt out whatever they have, and then you run out and then it's Tuesday and you still feel awful.)
posted by gjc at 6:32 PM on May 3, 2011

I am going through some serotonin issues and found this incredibly informative.

Stanford Professor Robert Sapolsky, posits that depression is the most damaging disease that you can experience. Right now it is the number four cause of disability in the US and it is becoming more common. Sapolsky states that depression is as real of a biological disease as is diabetes.
posted by punkfloyd at 7:01 PM on May 3, 2011 [3 favorites]

This isn't exactly new, but I am glad to see more proof In the near future I think we will discover that many 'neurotransmitters' serve multiple purposes throughout the body. After that it won't be a large leap to find that our body plays a role in much of our cognition.
posted by psycho-alchemy at 7:02 PM on May 3, 2011 [1 favorite]

(Found this video incredibly informative)
posted by punkfloyd at 7:02 PM on May 3, 2011

I find it interesting, seeing as there's a lot of connection between depression and gastrointestinal illness, with SSRIs and SNRIs working to treat both issues in many (from my experience working in mental health.)

I also am curious to know more as a person whose husband has ulcerative colitis that precipitated pretty severe depression that has resisted multiple drug therapies ( the depression, not the UC. That's well controlled now). I can't think that severe damage to gut lining and depression can be totally unrelated or only tangentially unrelated when serotonin supposedly plays a role in both. hrm.
posted by threeturtles at 7:38 PM on May 3, 2011

argh. Tangentially related
posted by threeturtles at 7:39 PM on May 3, 2011

Maias is quite right about stressfull, traumatic, or emotionally unhealthy situations causing cellular damage in the brain which initiates an inflammatory response to repair the damage.

Exercise has a huge affect on this because after exercising the body in fact raises inflammatory activity in order to repair tissue damage related to the exercise. After the exercise, particularly after exercising regularly you'll have less inflammation than when you started. Why? Because extra work has been done to repair the damage. Like stress, small amounts with ample time for repair and relaxing healthy experiences can easily be repaired, whereas too much exercise can actually cause inflammatory conditions in intense athletes. The same too much stress and trauma is simply too much for the brain.

Most depression research as of the last year has been focused on this process. Relaxation techniques are proving beneficial as well.

Tai chi:
"Subjects in the escitalopram and TCC condition were more likely to show greater reduction of depressive symptoms and to achieve a depression remission as compared with those receiving escitalopram and HE. Subjects in the escitalopram and TCC condition also showed significantly greater improvements in 36-Item Short Form Health Survey physical functioning and cognitive tests and a decline in the inflammatory marker, C-reactive protein, compared with the control group."

Gi Gong:
"Regression analysis indicated that the MQ group significantly improved overall QOL (t(144) = -5.761, P < 0.001), fatigue (t(153) = -5.621, P < 0.001), mood disturbance (t(122) =2.346, P = 0.021) and inflammation (CRP) (t(99) = 2.042, P < 0.044) compared with usual care after controlling for baseline variables."


I could go on but I'm getting sleepy.
posted by xarnop at 8:10 PM on May 3, 2011 [3 favorites]

(I'm writing a paper on that right now... lol I feel like it was random mentioning I'm sleepy... so many articles to work through! I wish I could post all of them here. It's fascinating stuff!)
posted by xarnop at 8:19 PM on May 3, 2011

Since I first read these articles about the "gut - brain" I have been amazed. Now serotonin's role. The nervous system is vastly more complex than we can imagine.
posted by WinstonJulia at 1:09 AM on May 4, 2011

the article/post is hazy on some basic dietary science: serotonin cannot be synthesized by humans.

A protein is a long sequence of different amino acids; there are twenty amino acids.

Eight of them are essential, these---including tryptophan---cannot be synthesized internally but rather must be foraged externally.

If you eat protein then you are eating tryptophan though some proteins have a higher proportion of Trp than others. Tryptophan is less prevalent than many other amino acids, comprising 1% of plant protein and 1.5% of animal protein. (list of specific high-Trp foods.) its not surprising (to me) then that something ubiquitious in our diet might end up with multiple functions.
----------------------------------
I cant wait for the corresponding NYT article on cholesterol: it clogs your heart and brain; its used to manufacture testosterone and estrogen; it helps you digest fat with bile; its converted to Vitamin D in the sun; it helps regulate the saltiness of your blood as aldersterone; it regulates blood sugar as cortisol, it mediates anti-inflammatory response and reigns in white blood cells....
posted by dongolier at 5:19 AM on May 4, 2011 [1 favorite]

The research on the positives of fat and cholesterol and even salt is very insteresting and provides even more compelling evidence that peoples behaviors are usually more healthful than we realize. I think more and more we will continue to find that people in our culture are not getting enough emotionally enriching activities, healthfull exercise and movement, relaxation, and meaningful social support. From a policy perspective, I think we need to begin to see the environments people are living in as the root of the disease process and address that instead of continualy researching what drugs we can pump people full of in order to continue living in unhealthy indadequate conditions.
posted by xarnop at 12:45 PM on May 4, 2011 [3 favorites]