Polygala tenuifolia!?
While doing some research on Pubmed I came across 3 studies which discussed the most frequently used nootropics in Traditional Chinese Medicine. The studies were fairly consistent with each other, in that they each mentioned the same 3-5 herbs.
“Of the 110 different natural products identified, those most frequently cited for forgetfulness were Polygala tenuifolia, Poria cocos, and Acorus spp., all of which have been cited repeatedly over the past 1800 years and appear among the 31 herbs indexed in a modern pharmacopoeia.” [1]
“We encountered Acoris gramineus rhizome, Panax ginseng, Polygala tenuifolia and Poria cocos as the four most frequently used herbs as single/herbal mixtures that were associated with positive cognitive enhancing outcomes” [2]
And May et al., 2012 listed the 5 most frequently used herbs for age related dementia and memory impairment to be, in descending order; Polygala tenuifolia, Rehmannia glutinosa, Poria cocos, Panax ginseng and Acorus ssp. [3]
Now lets quickly examine those 5 mentioned herbs.
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Panax ginseng is already well known and discussed and it’s nootropic effects aren’t very significant and I will therefore not delve into it in this article. {Read more at Examine}
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Acorus is a genus of grass species that’s roots contain the chemical β-asarone, which is both the chemical responsible for the nootropic effects and a known carcinogen (cancer-causing molecule), and is therefore not fit for consumption. {Read more at Examine}
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Poria cocos is a large woody “bulb” of an underground fungus, an energy and nutrient rich reserve. Almost all studies r.e. its nootropic potential are confounded with a variety of other herbs, since it’s usually tested in the context of its traditional use in TCM, where it is part of a variety of herbal blends. I was able to find only four studies where any aspect of P. cocos nootropic potential was tested by itself [5-8], and only one of those four had any significant results, where it was shown to promote LTP in vivo. [8] {no Examine article as of yet}
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Rehmannia glutinosa is a small flowering plant whose roots are used medicinally. The majority of nootropic research is on the metabolite Catalpol, which appears to be quite neuroprotective [9-23] and has minor evidence for cognitive boosting potential in unhealthy states [24, 25]. However traditional use suggests catalpol is not the primary active component of Rehmannia. Traditional preparation is quite time and labor intensive and significantly diminishes catalpol content [26-28], traditionally prepared Rehmannia also shows nootropic potential [29-33], and traditional preparation has been shown to greatly improve other aspects of Rehmannia’s medicinal properties (hemorheological) [28] {no Examine article as of yet}
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Leaving us with Polygala tenuifolia, the actual reason for this article. {no Examine article as of yet}
(Interesting side note is that in all 5 of these herbs, the roots are the active part of the plant, with the exception of Poria cocos, which has no roots, but is also underground)
Now I’m actually quite surprised that I hadn’t heard of Polygala yet. First off, it has randomized, double-blind, placebo-controlled trials on humans, both in young healthy adults [37] and the elderly (without cognitive decline) [38]. Both trials have shown it to be an effective nootropic, with a very reasonable daily dose of 300 mg (of patented extract, mind you), and in the trial with healthy young adults it was shown to be effective after four weeks, something even bacopa would have difficulty proving at that dose and duration.
Effects of BT-11 on memory in healthy humans
We previously reported that BT-11, the extract of dried roots of Polygala tenuifolia Willdenow, had neuroprotective effects and improved scopolamine- and stress-induced amnesia in rats. It also blocked the activity of acetylcholinesterase and enhanced glucose utilization in the rat brain. Therefore, we examined whether BT-11 could enhance memory in healthy humans. This study was a randomized, double-blind, placebo-controlled, parallel-group study of BT-11 in healthy adults. The participants were given capsules of BT-11 or placebo 3 times daily for 4 weeks. The Korean version of the California Verbal Learning Test (K-CVLT) and the Self-Ordered Pointing Test (SOPT) were used to assess verbal memory and working memory, respectively. The subjects in BT-11-treated group showed more significant increases in immediate recall on the K-CVLT than those in the placebo-treated group. In a comparison within each group, the subjects' scores on most subtests of the K-CVLT were significantly increased by both placebo and BT-11 treatment. Interestingly, the subjects' scores on the recognition subtest of the K-CVLT were significantly increased by BT-11 treatment but not by placebo treatment. Also, BT-11 treatment significantly reduced the number of errors on the SOPT, whereas placebo treatment did not. We are the first to show that BT-11 has memory-enhancing effects and may be a memory-enhancing drug in healthy adults
BT-11 is effective for enhancing cognitive functions in the elderly humans
Roots of Polygala tenuifolia Willdenow have been used in humans for centuries because of its sedative effects. We previously reported that BT-11, extracted from the roots of the plant, improved memory impairments in rats, enhanced memory in normal humans, and inhibited acetylcholinesterase activities in vitro. The present study was a randomized, double-blind, placebo-controlled comparison study to investigate whether BT-11 could enhance memory in the elderly humans. We used the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD) and the Mini-Mental State Examination (MMSE). In the elderly, the total CERAD scores were much more significantly increased in the BT-11-treated group (n=28) than in the placebo-treated group (n=25). Especially, the mean scores of word list recognition, constructional recall and praxis, and modified Boston naming test were markedly improved in BT-11-treated group than in placebo-treated group. In conclusion, BT-11 could enhance some cognitive functions including memory in the elderly humans and therefore may be used as nutraceuticals that provide health benefits, including disease prevention and/or treatment.
Animal data backs up the human trials, with improvements in memory in both young [39] and old healthy mice [40], with multiple active components, each showing promising nootropic potential by themselves, many with very very low active doses (THIS is a particular favorite of mine). Its also shown to have potent anti-depressant effects [4, 41-45], as well as anxiolytic and adaptogenic properties [46-50].
Its cognitive boosting mechanisms seem to primarily involve the NR2B> CaMKII (& ERK1/2) > CREB > BDNF pathway [51-55], which leads to enhanced synaptic plasticity and LTP [51-55]. Some of its other nootropic effects are probably mediated through increasing neural stem cells [56, 57], enhancing autophagy [58] while turning on cell survival genes (possibly through AMPK) [59], increasing brain antioxidant activity [60-62], and augmenting NMDAR control [51, 63]. Together these mechanisms, and potentially other mechanisms, provide Polygala with it's incredibly neuroprotective abilities. [64-82]
I mentioned Polygala tenuifolia to Kurtis Frank of Examine.com and even though he admitted that he was not as familiar with Polygala as he was with the other supplements he’s extensively researched, he agreed with my projection that Polygala is probably the 2nd most promising herbal nootropic currently, behind only Bacopa monnieri.
Since the patented BT-11 doesn’t seem to be available, I’m currently taking 50 drops daily of an alcohol-free extract of polygala. Ive been talking Polygala with several other herbal nootropics as well as my simplistic version of the Mr Happy Stack (citicoline & fish oil) and have noticed dramatic increases in procedural memory and tangible but less significant improvements and declarative memory.
References
1 http://www.ncbi.nlm.nih.gov/pubmed/23433049
2 http://www.ncbi.nlm.nih.gov/pubmed/22303969
3 http://www.ncbi.nlm.nih.gov/pubmed/22311547
4 http://www.ncbi.nlm.nih.gov/pubmed/24520403
Poria cocos
5 http://www.ncbi.nlm.nih.gov/pubmed/20099523
6 http://www.ncbi.nlm.nih.gov/pubmed/15351791
7 http://www.ncbi.nlm.nih.gov/pubmed/15500267
8 http://www.ncbi.nlm.nih.gov/pubmed/7655419
Rehmannia
9 http://www.ncbi.nlm.nih.gov/pubmed/17049947
10 http://www.ncbi.nlm.nih.gov/pubmed/16269165
11 http://www.ncbi.nlm.nih.gov/pubmed/20123001
12 http://www.ncbi.nlm.nih.gov/pubmed/19635525
13 http://www.ncbi.nlm.nih.gov/pubmed/19631247
14 http://www.ncbi.nlm.nih.gov/pubmed/23550774
15 http://www.ncbi.nlm.nih.gov/pubmed/18840519
16 http://www.ncbi.nlm.nih.gov/pubmed/18573305
17 http://www.ncbi.nlm.nih.gov/pubmed/18423111
18 http://www.ncbi.nlm.nih.gov/pubmed/18281203
19 http://www.ncbi.nlm.nih.gov/pubmed/18022141
20 http://www.ncbi.nlm.nih.gov/pubmed/17698178
21 http://www.ncbi.nlm.nih.gov/pubmed/17512520
22 http://www.ncbi.nlm.nih.gov/pubmed/22305339
23 http://www.ncbi.nlm.nih.gov/pubmed/23612000
24 http://www.ncbi.nlm.nih.gov/pubmed/17992998
25 http://www.ncbi.nlm.nih.gov/pubmed/17078935
26 http://www.ncbi.nlm.nih.gov/pubmed/24914291
27 http://www.ncbi.nlm.nih.gov/pubmed/21532190
28 http://www.ncbi.nlm.nih.gov/pubmed/8717282
29 http://www.ncbi.nlm.nih.gov/pubmed/15658822
30 http://www.ncbi.nlm.nih.gov/pubmed/21983027
31 http://www.ncbi.nlm.nih.gov/pubmed/21876380
32 http://www.ncbi.nlm.nih.gov/pubmed/24187876
33 http://www.ncbi.nlm.nih.gov/pubmed/12817566
34 http://www.ncbi.nlm.nih.gov/pubmed/24584758
35 http://www.ncbi.nlm.nih.gov/pubmed/16600621
36 http://www.ncbi.nlm.nih.gov/pubmed/24570113
Polygala
37 http://www.ncbi.nlm.nih.gov/pubmed/19429065
38 http://www.ncbi.nlm.nih.gov/pubmed/19699261
39 http://www.ncbi.nlm.nih.gov/pubmed/23499702
40 http://www.ncbi.nlm.nih.gov/pubmed/24744810
41 http://www.ncbi.nlm.nih.gov/pubmed/20018220
42 http://www.ncbi.nlm.nih.gov/pubmed/20645779
43 http://www.ncbi.nlm.nih.gov/pubmed/19726361
44 http://www.ncbi.nlm.nih.gov/pubmed/20541923
45 http://www.ncbi.nlm.nih.gov/pubmed/24614095
46 http://www.ncbi.nlm.nih.gov/pubmed/20645780
47 http://www.ncbi.nlm.nih.gov/pubmed/11812522
48 http://www.ncbi.nlm.nih.gov/pubmed/15305046
49 http://www.ncbi.nlm.nih.gov/pubmed/19827305
50 http://www.ncbi.nlm.nih.gov/pubmed/21585386
51 http://www.ncbi.nlm.nih.gov/pubmed/23029109
52 http://www.ncbi.nlm.nih.gov/pubmed/19684611
53 http://www.ncbi.nlm.nih.gov/pubmed/24877714
54 http://www.ncbi.nlm.nih.gov/pubmed/24488601
55 http://www.ncbi.nlm.nih.gov/pubmed/22286914
56 http://www.ncbi.nlm.nih.gov/pubmed/18693285
57 http://www.ncbi.nlm.nih.gov/pubmed/22179853
58 http://www.ncbi.nlm.nih.gov/pubmed/24248062
59 http://www.ncbi.nlm.nih.gov/pubmed/21195155
60 http://www.ncbi.nlm.nih.gov/pubmed/20645784
61 http://www.ncbi.nlm.nih.gov/pubmed/21423642
62 http://www.ncbi.nlm.nih.gov/pubmed/20609361
63 http://www.ncbi.nlm.nih.gov/pubmed/15481649
64 http://www.ncbi.nlm.nih.gov/pubmed/18712849
65 http://www.ncbi.nlm.nih.gov/pubmed/12725562
66 http://www.ncbi.nlm.nih.gov/pubmed/21536104
67 http://www.ncbi.nlm.nih.gov/pubmed/22759267
68 http://www.ncbi.nlm.nih.gov/pubmed/16946504
69 http://www.ncbi.nlm.nih.gov/pubmed/19208093
70 http://www.ncbi.nlm.nih.gov/pubmed/15308312
71 http://www.ncbi.nlm.nih.gov/pubmed/15374606
72 http://www.ncbi.nlm.nih.gov/pubmed/15464827
73 http://www.ncbi.nlm.nih.gov/pubmed/17827729
74 http://www.ncbi.nlm.nih.gov/pubmed/16437744
75 http://www.ncbi.nlm.nih.gov/pubmed/15256744
76 http://www.ncbi.nlm.nih.gov/pubmed/21740104
77 http://www.ncbi.nlm.nih.gov/pubmed/16989524
78 http://www.ncbi.nlm.nih.gov/pubmed/12391609
80 http://www.ncbi.nlm.nih.gov/pubmed/17329848
81 http://www.ncbi.nlm.nih.gov/pubmed/23688946
82 http://www.ncbi.nlm.nih.gov/pubmed/7655419
Edited by Bateau, 30 July 2014 - 09:57 PM.