I’ve wondered this as well and I’d never seen 5-HT reuptake inhibitors or MAOi drugs associated with VHD. Worth a deeper dive after reading the news release you linked @NotSure

This was an interesting paper for people with Parkinson’s disease. Mianserin was the only mental health medication that improved lifespan.

Which appears to be a mix of 5-HT antagonist, histamine antagonist, alpha antagonist, perhaps opioid agonist(kor?), and noradrenaline reuptake inhibitor.

The survival effects they found in the general population for most of the drugs that showed benefit in PD (although not mianserin) were interesting as well. I take buproprion, which has NRI effects, so I found mianserin an interesting one. Buproprion is approved in Norway and shows up in the NorPD database that they combed, so I’m guessing it didn’t show a survival benefit.

The opioid/opium medications were surprising as well.

This was one very interesting/surprising! At least for ‘harder’ opiates I’d imagine the association would be inverted due to their use in chronic pain and terminal diseases. There’s also associations between opiate use and cancer, as well as mechanistic data showing that opiates modulate immune cell function, although I don’t think a causal link has ever been demonstrated.

I was very happy to see this data since I’ve been using 7-hydroxymitragynine daily for the past year and a half. It’s a pretty remarkable substance (weak partial mu agonism with arrestin-insensitivity) that doesn’t evoke respiratory depression like the opium-derived alkaloids and other classical opiates, but it’s still not something I’m thrilled about having used so much either.

From Wikipedia:
"Around this time, Shulgin began showing early signs of dementia, mostly severe loss of short-term memory. With progression of the dementia since 2010, his wife, Ann Shulgin, had been trying to sell part of their property to raise more money to cover care costs. "

Sasha was also exposed to a lifetime of organic solvents and other lab chemicals (he had a gung-ho attitude in this regard—not even a fume hood in his personal lab), didn’t watch his diet at all, and tended to drink and use stimulants as well. He went downhill really fast in his last few years and ironically, it was the heart valve surgery which seemed to precipitate that. He just never really recovered from it.

Altogether though he made it to 88, which is pretty damn good considering his wide exposure to xenobiotics. His wife Ann made it to 91 and Darrell Lemaire (another guy who ran around in Sasha’s group) made it to 92, so they’re definitely great anecdotal examples of psychedelic use and longevity.

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Thanks for the reply. Buproprion not having survival benefit is odd (NRI’s). Other medications that have alpha antagonism also did not make the list.
Would be cool to see ITP try some Opioids one day. Hopefully things go well with the 7-hydroxymitragynine.

Did not know that about Sasha being exposed to so many chemicals. He must have great genetics to be able to do all that stuff and live until 88.

@NotSure Thanks for the findings.

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chatGPT appears to disagree with this conclusion w/r/t psilocybin (not SSRIs).

Does the use of psilocybin cause decreased serotonin transporter activity in the mitral valve and contribute to progression of degenerative mitral regurgitation? What about microdosing psilocybin?

ChatGPT said:
There is currently no direct scientific evidence linking psilocybin use (including microdosing) to decreased serotonin transporter (SERT) activity specifically in the mitral valve or to the progression of degenerative mitral regurgitation (DMR). Whew!
It does, however, point out that:

  • :warning: Theoretical risks exist for substances that act on 5-HT2B receptors (e.g., fenfluramine), but psilocybin has low affinity for this receptor and is not known to cause valvular fibrosis.

But as I’m not a neuropharmacologist I’ll leave it to others to evaluate this response.


Yes, I must be careful to not use the term psychedelics so loosely. There must be so many compounds classified as psychedelics. Is psilocybin one of the only psychedelics that doesn’t show decreased serotonin transporter activity (SERT)?

The case for psilocybin as an alternative to SSRI’s for depression and longevity looks really convincing. Besides, I find the side effects of psilocybin rather enjoyable.

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Psilocin (the active metabolite of psilocybin) hits a bunch of different GPCRs, so it’s kind of a wild guess as to which receptor(s) are mediating the longevity effects, but TrkB seems like an unlikely candidate in light of this recent paper (lead author is Bryan Roth, who’s basically the foremost expert on structure and function of serotonin receptors): The polypharmacology of psychedelics reveals multiple targets for potential therapeutics.

Recent studies have suggested that psychedelics such as LSD directly interact with TrkB with high affinity, promoting BDNF-mediated neuroplasticity and antidepressant-like effects via allosteric potentiation of BDNF signaling in active synapses.8 To investigate this, we screened LSD across 450 human kinases, including TrkB, but found no significant interactions between LSD and any tested human kinases. Further experiments in transfected cells revealed no effect of LSD or psilocin on BDNF-mediated activation of a TrkB reporter. We note that similar negative preliminary results, which have not yet been published in a peer-reviewed journal, were recently reported by Boltaev et al.63

Also, @mattbagg has screened some psychedelics at TrkB and found nothing (hope you don’t mind if I link your Reddit comment, Matt):

I think their first finding, that psychedelics are high affinity TrkB ligands, is simply wrong. They are assuming that HEK293T cells don’t naturally express any 5-HT1 receptors, which would be a more plausible explanation for their results. Then their later LSD results use implausibly high concentrations that are unlikely to occur in vivo. I screened some tryptamines with TrkB PAM and agonist assays and did not see anything.

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Mitochondria in neurons, in addition to their primary role in bioenergetics, also contribute to specialized functions, including regulation of synaptic transmission, Ca2+ homeostasis, neuronal excitability, and stress adaptation. However, the factors that influence mitochondrial biogenesis and function in neurons remain poorly elucidated. Here, we identify an important role for serotonin (5-HT) as a regulator of mitochondrial biogenesis and function in rodent cortical neurons, via a 5-HT2A receptor-mediated recruitment of the SIRT1–PGC-1α axis, which is relevant to the neuroprotective action of 5-HT. We found that 5-HT increased mitochondrial biogenesis, reflected through enhanced mtDNA levels, mitotracker staining, and expression of mitochondrial components. This resulted in higher mitochondrial respiratory capacity, oxidative phosphorylation (OXPHOS) efficiency, and a consequential increase in cellular ATP levels. Mechanistically, the effects of 5-HT were mediated via the 5-HT2A receptor and master modulators of mitochondrial biogenesis, SIRT1 and PGC-1α. SIRT1 was required to mediate the effects of 5-HT on mitochondrial biogenesis and function in cortical neurons. In vivo studies revealed that 5-HT2A receptor stimulation increased cortical mtDNA and ATP levels in a SIRT1-dependent manner. Direct infusion of 5-HT into the neocortex and chemogenetic activation of 5-HT neurons also resulted in enhanced mitochondrial biogenesis and function in vivo. In cortical neurons, 5-HT enhanced expression of antioxidant enzymes, decreased cellular reactive oxygen species, and exhibited neuroprotection against excitotoxic and oxidative stress, an effect that required SIRT1. These findings identify 5-HT as an upstream regulator of mitochondrial biogenesis and function in cortical neurons and implicate the mitochondrial effects of 5-HT in its neuroprotective action.

I’m seeing conflicting ideas regarding 5-HT2A receptors with regard to mitochondria, longevity, and depression. Due to my interest in myo-inositol and it’s effect on depression and longevity, I’ve come up with some conflicting research regarding 5-HT2A receptors. Perhaps someone can enlighten me?

Psilocybin is a 5-HT2A agonist which has been cited as one of the causes of its antidepressant properties. However, fluoxetine and myo inositol are 5-HT2A antagonist and that is cited as the reason for their positive effect on mood.

[Effects of myo-inositol versus fluoxetine and imipramine pretreatments on serotonin 5HT2A and muscarinic acetylcholine receptors in human neuroblastoma cells - PubMed]

It also looks like myo inositol has a positive effect on mitochondria, sperm motility, and testosterone.

[Respiratory Mitochondrial Efficiency and DNA Oxidation in Human Sperm after In Vitro Myo-Inositol Treatment - PMC]

[Effect of Myoinositol and Antioxidants on Sperm Quality in Men with Metabolic Syndrome - PubMed]

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