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Uncaria rhynchophylla

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Looking at adding  Cat's Claw Extract Powder - [20:1] to my diet but this one is Uncaria rhynchophylla - I'm after geissoschizine methyl ether (GM), GM is present in the hook at 0.08% but it's potent...


With the alkaloids:

- the alkaloids in this plant are NMDA receptor inhibitors. While the IC50 values are too high for what is normally found in the brain, it is possible that mild inhibition (less than 20%) may occur with high doses.
- geissoschizine methyl ether is a potent agonist of the 5-HT1A receptors while it is inhibitory at the 5-HT2A, 5-HT2C, and 5-HT7 receptors at the same concentration range, with the possibility of being a partial agonist at higher doses.
- anxiolytic and enhanced social behaviour




This is contrary to U tormentosa cat's claw, which contains similar alkaloids and is found in nature in two different chemotypes producing different alkaloidal constituents. Pentacyclic oxindoles are found in the roots of one type, while the tetracyclic oxindoles are present in the second type. Mitraphylline and isomitraphylline, seen as the main bioactives and usually present in older leaves or the stem bark but rhynchophylline and isorhynchophylline are also present. Anyone tried this one?


The reason I'm after this plant:

-Effective constituent for dementia [1] and schizophrenia [2]


"Geissoschizine methyl ether (GM) is one of the indole alkaloids in Uncaria hook, and an active ingredient of yokukansan (YKS) that improves behavioral and psychological symptoms of dementia (BPSD) in patients with several types of dementia. The pharmacological action of GM has been related to various serotonin (5-HT) receptor subtypes. Here we describe previous findings and our own data to review the binding characteristics of GM to the 5-HT receptor subtypes. Competitive receptor-binding assays showed that GM bound the following 5-HT receptor subtypes: 5-HT1A, 5-HT1B, 5-HT2A, 5-HT2B, 5-HT2C, 5-HT4, 5-HT5A, 5-HT6, and 5-HT7. Subsequent agonist/antagonist activity assays showed that GM had partial agonistic activity for 5-HT1A receptors and antagonistic activity for 5-HT2A, 5-HT2B, 5-HT2C, and 5-HT7 receptors. Pharmacokinetic studies showed that GM was metabolized by various CYP isoforms, mainly CYP3A4. Parent/unchanged GM was detected in both the blood and brain of rats after oral administration of YKS. In autoradiography analyses using rat brain slices, GM that entered the brain was presumed to bind to 5-HT1A, 5-HT2A, 5-HT2B, 5-HT2C, and 5-HT7 receptors in neuron-like large cells mainly in the frontal cortex. In conclusion, these results suggest that GM is a pharmacologically important alkaloid that regulates various serotonergic activities or functions by binding to multiple 5-HT receptor subtypes."

Anyone have experience with the plant?

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tormentosa has been an absolute miracle plant for me. Unfortunately, I can't say that I found it had any obvious psychoactive properties. Rather I've used an extract of Pentacyclic oxindoles (PCO) chemotype - quite expensive - for rather crippling chronic rhinitis/dust allergy/hay fever, which really interfered with life, dripping pools of snot constantly, making it hard to concentrate, making me grumpy as and leaving my nose red raw.  All of this, coupled with a fear of going outside because of pollen, really affected my mood and general QOL. It sounds like such an innocuous disease, but it wasn't.  Non-sedating antihistamines made no difference (rapid tachyphylaxis), only partial response to nasal steroid sprays, sedating antihistamines made a difference, but left me like a zombie for work. 


It took a week to work, but to be honest, it was only when I ran out of the extract that I realised how well it had worked - took 3 days and the symptoms began to return which is when you realise just how much better life was. After about 6 months of taking, I'm really able to have quite long periods without it without any significant resurgence of symptoms - a bad afternoon here and there is perfectly acceptable.  Definitely due to a TH2 dominant immunity.


With regards to it's healing properties, I feel like it has an anti inflammatory action at a genetic transcription level, and this may have a beneficial effect on cognitive function.  It is interesting to note that cats claw is often used as an admixture to ayahuasca for its healing properties. There are several reports that it potentiated the mitragynine group alkaloids of kratom. 


Have you looked into sarcosine for schizophrenic cognitive symptoms? Huperzine is another interesting Ndma antagonist but lacks the interesting seratonergic component of the above uncaria. Bacopa is worth looking into for normalising seratonergic transmission - increasing SERT and tryptophan hydroxalase expression. 

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