Polygonum cuspidatum / Japanse duizendknoop

Fallopia japonica (Houtt.) Ronse Decr. Familie Polygonaceae. 
Onderste bladen meestal niet langer dan 15(-18) cm; bladvoet recht afgeknot of breed wigvormig. Bladen van onderen ook op de nerven kaal, zijnerven van de bladen 4-6 paar. Plant rechtopstaand, overblijvend, met stevige wortelstokken. Stempels fijn verdeeld. Bloemen functioneel tweehuizig. Bloeiwijzeas met zeer korte, 1- of 2-cellige haren. Tuitjes in de bloeiwijze vrijwel kaal, afgerond of kort toegespitst. 

Hoogte bloeiende plant
1,00-3,00 m.
Geofyt, Hemikryptofyt.

Op vochtige, voedselrijke grond in bermen, aan bosranden, op spoordijken, aan beekoevers.

Japanse Duizendknoop is, een belangrijke bron voor resveratrol. Resveratrol is een natuurlijke verbinding die in planten ontstaat als reactie op schimmelinfecties, beschadiging, en UV-straling. Het wordt beschouwd als een onderdeel van hun "afweermechanisme". Planten maken deze stof om hun gevoelige weefsels te beschermen tegen ziekten en aandoeningen.
Resveratrol heeft medicinaal gezien meerdere positieve werkingen. Eén daarvan is dat het een heel sterke antioxidant is. Een andere belangrijke werking is dat het de levensduur van gezonde cellen verlengt en het voorkomt dat woekercellen ontstaan. Om deze redenen wordt het in de natuurgeneeskunde ook toegepast bij kanker. 
Resveratrol wordt in de handel veel als een uit de plant afgescheiden, geïsoleerde stof aangeboden. Je koopt dan puur resveratrol. Bij Lyme is juist de werking van de gehele plant, dus van de Japanse Duizendknoop als geheel, belangrijk. De gehele plant bevat, behalve resveratrol nog talloze andere stoffen en deze blijken in hun onderlinge samenhang juist bij de ziekte van Lyme een rol te kunnen spelen die gunstiger is dan van geïsoleerd resveratrol alleen. Op zich is het goed om resveratrol te gebruiken, maar toepassing van de hele plant, in het geval van Lyme, is effectiever. Uitgebreide achtergrondinformatie hierover vindt je o.a. in het boek van S.H. Buhner, "Healing. Lyme".

The whole plant contains several other constituents and, when taken to treat Lyme disease and it's symptoms, has proven to be very effective in bringing  relief to many people suffering from the disease and its coinfections. Japanese Knotweed tastes bitter and sour with energetics being cold and dry. It is considered stimulating and astringent. Japanese Knotweed  has also, according to herbalist Stephen Buhner, been proliferating across bioregions immediately preceding the emergence of Lyme disease. I have witnessed this occurrence in the area of central New York State where I live. I  heard Stephen speak at a conference about this about 5 years ago and, at the time, I had minimal knowledge or experience with Lyme disease and its treatment. I had also never seen a Japanese knotweed plant. I began to notice them in my locality about 4 years ago and, even then, it was only sparsely on  the edges of roads and in vacant lots where houses or small industries used to exist. It has spread dramatically in the last three years simultaneously with the abundant increase in deer ticks . The ticks have been slowly increasing as the winters have been slowly getting warmer.

Japanese knotweed is in the Buckwheat family, and is generally not liked in western nations because it can grow up to one metre per month, its roots travel over three metres deep, and they spread up to 7 metres in every direction. It grows through concrete, asphalt, dams, and buildings. Japanese Knotweed is known as Polygonum cuspidatum in North America, in Europe it is known as Fallopia japonica. It is a very tolerant plant and survives in a wide range of soil types. Its rhizomes can survive temperatures of −35 °C (−31 °F).

Distinguishing Features: In the early spring, Japanese knotweed looks like nondescript fat, green, red-flecked stalks poking up from the ground. Although the young leaves are hard to identify, the big clue to the plant's identity are the dead stalks from the year before. They resemble bamboo, are hollow, lightweight and have wooden-like stems. By early summer the mature Japanese knotweed stems are hollow with purple speckles and are very tall. The leaf growth alternates on each side of the stem creating an obvious knotweed zigzag pattern.

Flowers: The white flowers are very small but numerous and they form showy, greenish-white branching panicles from the axils of upper leaves. These ‘spike’ of flowers are about 10cm in length. Japanese knotweed usually flowers from July to September.

Leaves: Japanese knotweed leaves are alternate, broadly ovate, square-cut or slightly angled at the base, abruptly pointed at the tip with the tip often stretched out, colourless and are hairless.

Height: The Japanese knotweed can grow up to one metre every month and can reach heights of up to four metres.

Habitat: Japanese knotweed can tolerate a variety of adverse conditions, including dense shady areas, high temperatures, high salinity soils and drought. Knotweed is commonly found near water sources, in low-lying areas, waste areas, and around old home sites. Japanese knotweed is native to Japan and grows in Canada, U.S., England, some parts of Europe, Australia, New Zealand, China, Korea, and eastern Asia.

Edible parts: The best edible part of this plant are the young shoots, preferably when they are about 15-20 centimetres tall (6-8”). Depending on your taste buds you may think they have a lemony taste, some say it is more like rhubarb. Young shoots can be consumed raw or cooked and the growing tips and the unfurled leaves on the stalk and branches are edible. Stems can be sliced and steamed, simmered in soups, used in sauces, jams and fruit compotes. Japanese Knotweed is a great source of vitamins A and C. It also provides many vital minerals including iodine and is loaded with resveratrol.

Similar plants: Polygonum sachalinense, Polygonum aubertii.

Recipe: Knotweedbread

>> 2 cups unbleached flour
>> 1/2 cup organic cane sugar
>> 1 1/2 tsp baking powder
>> 1/2 tsp salt
>> 1 egg
>> 1/8 cup honey
>> 2 tbsp sunflower or safflower oil
>> 3/4 cup orange juice
>> 3/4 cup chopped walnuts
>> 1 cup puréed Japanese knotweed

Sift all dry ingredients together into a large bowl. In another bowl, beat the egg, oil, honey and orange juice. Add walnuts and purée to dry ingredients. Then add the moist ingredients. Blend only until all ingredients are moist. Spoon into a greased loaf pan.

Bake about 1 hour at 350°F or until a knife inserted in the centre comes out dry. Cool on a rack.

Rhizoma Polygoni Cuspidati (Chinese fytotherapie TCM)

Rhizoma Polygoni Cuspidati is also named Hu Zhang , 虎杖, Giant Knotweed Rhizome
Hu Zhang
Hu Zhang
Hu Zhang (Rhizoma Polygoni Cuspidati)——Ming Yi Bie Lu (Miscellaneous Records of Famous physicians)

The root of perennial herbaceous plant Polygonum cuspidatum Sieb. et Zucc.

Most areas of China.

Collected in spring and autumn.

The true smell and taste
Slight smell, stightly bitter and astringent.

Best quality
Thick, without internal hollow.


Bitter and cold; liver, gallbladder and lung meridians entered.

Excrete dampness and remove jaundice, clear heat and remove toxicity, resolve blood stasis and stop pain, resolve phlegm and relieve cough.


A. Jaundice of damp-heat type, stranguria

It is good at clearing damp-heat from liver and gallbladder and inducing diuresis, so it is the essential herb for jaundice of damp-heat type. It can be decocted alone or combined with other herbs such as Yin Chen Hao, Huang Bai and Zhi Zi to strengthen the actions of clearing damp-heat and alleviating jaundice. For stranguria due to damp-heat accumulation in bladder manifested as difficult and painful urination, it can be used alone or combined with the diuresis-inducing and stranguria-treating herbs such as Mu Tong, Che Qian Zi and Qu Mai to mutually strengthen. It is also indicated for leukorrhagia of damp-heat type for its actions of clearing heat and excreting dampness. It is usually combined with the heat-clearing, damp-removing and leucorrhagia-stopping herbs such as Huang Bai, Bi Xie and Qian Shi.

B. Scald, carbuncle, swelling and sore

It has the actions of cooling blood, clearing heat and removing toxicity, activating blood and alleviating pain. For scald, it is usually used alone or combined with Di Yu and Bing Pian for external application. It or they can be ground into powder for local application or mixed with oil for external application. Its or their decoction can also be used for local application. For carbuncle, swelling and sore due to damp-heat accumulation, it can be decocted for washing or smashed for local application. To strengthen the action, it can also be decocted with the heat-clearing and toxicity-removing herbs such as Pu Gong Ying, Jin Yin Hua and Lian Qiao for oral taking.

C. Amenorrhea dysmenorrhea, mass, trauma and arthralgia of wind-damp type

It has the actions of activating blood and resolving blood stasis to alleviate pain. It is indicated for all syndromes due to blood stasis. For amenorrhea and dysmenorrhea due to blood stasis, it is usually combined with the herbs of activating blood and inducing menstruation to alleviate pain such as Tao Ren, Yan Hu Suo and Hong Hua. For mass, it is usually combined with the blood-breaking and mass-eliminating herbs such as San Leng and E Zhu. For pain due to trauma, it is usually combined with Dang Gui, Ru Xiang and Mo Yao to strengthen the actions of activating blood, relieving swelling and alleviating pain.

It is also indicated for chronic arthralgia due to qi and blood stagnation and transforming into heat manifested as redness, swelling and pain of joints, because it has the actions of draining damp, activating blood and unblocking meridians to stop pain. It can be used alone for decocting or dunking into wine, or combined with the wind-damp-dispelling herbs such as Fang Feng, Qin Jiao and Fang Ji.

D. Cough due to lung heat

It has the actions of purging heat, resolving phlegm and stopping cough. It is especially good for cough due to lung heat. It can be decocted alone or combined with Bei Mu, Pi Pa Ye and Xing Ren to strengthen the actions of clearing lung heat and resolving phlegm to stop cough.

Additionally, it also has the actions of purging heat and promoting defecation, cooling blood and stopping bleeding. It is also indicated for constipation due to heat accumulation, hematemesis, hematochezia and hemorrhoids with bleeding.

Dosage and Administrations
Decoct 9~15g. Proper dosage is for external application. It can be externally used by washing with its decoction, or be ground into powder for local application, or be prepared as ointment for local application.

It is contraindicated for pregnant women.

Int J Prev Med. 2013 Apr;4(Suppl 1):S1-4. Effects of polygonum cuspidatum containing resveratrol on inflammation in male professional basketball players.Zahedi HS1, Jazayeri S, Ghiasvand R, Djalali M, Eshraghian MR.
Exercise can lead to acute oxidative stress, which can result in oxidative damage and induce inflammation. Resveratrol may reduce the levels of inflammatory cytokines. Thus, we investigated the effects of this compound on the plasma levels of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) in male professional basketball players.
Twenty healthy male professional basketball players were randomized into two groups (10 each). For 6 weeks, they received daily either 200 mg of polygonum cuspidatum extract (PCE) standardized to contain 20% trans-resveratrol equivalent to 40 mg trans-resveratrol or placebo. Indices of inflammation were measured before and after 6 weeks of supplementation.
There was a significant reduction in plasma levels of TNF-a and IL-6 after 6 weeks of supplementation; while no change was observed in these markers in the control group.
Present study shows that 6 weeks of PCE containing resveratrol supplementation reduces the inflammation in male professional basketball players.

J Ethnopharmacol. 2013 Jul 30;148(3):729-45. doi: 10.1016/j.jep.2013.05.007. Epub 2013 May 22.
Botany, phytochemistry, pharmacology, and potential application of Polygonum cuspidatum Sieb.et Zucc.: a review.
Peng W1, Qin R, Li X, Zhou H.
Polygonum cuspidatum Sieb. et Zucc. (Polygonum cuspidatum), also known as Reynoutria japonica Houtt and Huzhang in China, is a traditional and popular Chinese medicinal herb. Polygonum cuspidatum with a wide spectrum of pharmacological effects has been used for treatment of inflammation, favus, jaundice, scald, and hyperlipemia, etc.
The present paper reviews the traditional applications as well as advances in botany, phytochemistry, pharmacodynamics, pharmacokinetics and toxicology of this plant. Finally, the tendency and perspective for future investigation of this plant are discussed, too.
A systematic review of literature about Polygonum cuspidatum is carried out using resources including classic books about Chinese herbal medicine, and scientific databases including Pubmed, SciFinder, Scopus, the Web of Science and others.
Polygonum cuspidatum is widely distributed in the world and has been used as a traditional medicine for a long history in China. Over 67 compounds including quinones, stilbenes, flavonoids, counmarins and ligans have been isolated and identified from this plant. The root of this plant is used as the effective agent in pre-clinical and clinical practice for regulating lipids, anti-endotoxic shock, anti-infection and anti-inflammation, anti-cancer and other diseases in China and Japan.
As an important traditional Chinese medicine, Polygonum cuspidatum has been used for treatment of hyperlipemia, inflammation, infection and cancer, etc. Because there is no enough systemic data about the chemical constituents and their pharmacological effects or toxicities, it is important to investigate the pharmacological effects and molecular mechanisms of this plant based on modern realization of diseases' pathophysiology. Drug target-guided and bioactivity-guided isolation and purification of the chemical constituents from this plant and subsequent evaluation of their pharmacologic effects will promote the development of new drug and make sure which chemical constituent or multiple ingredients contributes its pharmacological effects. Additionally, chemicals and their pharmacological effects of the other parts such as the aerial part of this plant should be exploited in order to avoid resource waste and find new chemical constituents.

J Tradit Complement Med. 2013 Jul;3(3):182-7. doi: 10.4103/2225-4110.114905.
Anti-inflammatory Activity of the Invasive Neophyte Polygonum Cuspidatum Sieb. and Zucc. (Polygonaceae) and the Chemical Comparison of the Invasive and Native Varieties with regard to Resveratrol.
Polygonum cuspidatum Sieb. and Zucc. has been traditionally used as a member of many anti-inflammatory polyherbal formulations, but is now a widespread invasive neophyte in Europe and America. To discuss if the invasive variety is chemically identical to the native one in traditional medicine, the different constituents of the invasive variety compared to the native variety were isolated and their anti-inflammatory activity was tested. Resveratroloside and catechin-(4α→8)-catechin, the newly found constituents in the invasive variety, have similar nitric oxide (NO) inhibition potency as that of piceid (the major constituent of P. cuspidatum), but the newly found major constituent, i.e., piceatannol glucoside, showed no apparent effect. On the other hand, as a marker, the total content of resveratrol in the methanol root extract after glucosidase hydrolysis was measured and compared between the invasive and native varieties. The total content of resveratrol measured in the root extracts of the Swiss sample was about 2.5 times less than that of the Chinese one. This study brings attention to the point that when the invasive variety of P. cuspidatum is used in traditional medicine, the chemical difference should be kept in mind.

Bioorg Med Chem Lett. 2001 Jul 23;11(14):1839-42. Phytoestrogens from the roots of Polygonum cuspidatum (Polygonaceae): structure-requirement of hydroxyanthraquinones for estrogenic activity. Matsuda H1, Shimoda H, Morikawa T, Yoshikawa M.
The methanolic extract from the roots of Polygonum (P.) cuspidatum was found to enhance cell proliferation at 30 or 100 microg/mL in MCF-7, an estrogen-sensitive cell line. By bioassay-guided separation from P. cuspidatum with the most potent activity, emodin and emodin 8-O-beta-D-glucopyranoside were isolated as active principles. The methanolic extracts from Polygonum, Cassia, Aloe, and Rheum species, which were known to contain anthraquinones, also showed the MCF-7 proliferation. As a result of the evaluation of various anthraquinones from plant sources and synthetic anthraquinones, aloe-emodin, chrysophanol, chrysophanol 8-O-beta-D-glucopyranoside, and 1,8-dihydroxyanthraquinone showed weak activity. On the other hand, alizalin and 2,6-dihydroxyanthraquinone as well as emodin having the 2- and/or 6-hydroxyl groups showed potent activity. These results show that the unchelated hydroxyl group is essential for strong activity. Emodin and 2,6-dihydroxyanthraquinone also inhibited 17beta-estradiol binding to human estrogen receptors (ERs) with K(i) values of 0.77 and 0.31microM for ERalpha and 1.5 and 0.69 microM for ERbeta. These findings indicate that hydroxyanthraquinones such as emodin are phytoestrogens with an affinity to human estrogen receptors.

In Vivo. 2015 Mar-Apr;29(2):255-61.
Crude extract of Polygonum cuspidatum promotes immune responses in leukemic mice through enhancing phagocytosis of macrophage and natural killer cell activities in vivo. Chueh FS1, Lin JJ2, Lin JP3, Yu FS4, Lin JH5, Ma YS6, Huang YP7, Lien JC8, Chung JG9.
Polygonum cuspidatum is a traditional Chinese herbal medicine used in the treatment of various diseases. In the present study, we investigated whether the crude extract of Polygonum cuspidatum (CEPC) could affect immune responses of murine leukemia cells in vivo. Normal BALB/c mice were i.p. injected with WEHI-3 cells to generate leukemic mice and then were treated orally with CEPC at 0, 50, 100 and 200 mg/kg for three weeks. Animals were weighed and blood, liver, spleen samples were collected for further analyses. Results indicated that CEPC did not significantly affect the body and liver weight of animals, but reduced the weight of spleen when compared to control groups. Flow cytometric assay demonstrated that CEPC increased the percentage of CD3- (T-cell marker) and CD19- (B-cell marker) positive cells, but reduced that of CD11b-positive ones (monocytes). However, it did not significantly affect the proportion of Mac-3-positive cells (macrophages), compared to control groups. Results indicated that CEPC promoted phagocytosis by macrophages from blood samples at all examined doses but did not affect that of macrophages from the peritoneal cavity. CEPC also promoted natural killer cell activity of splenocytes at 200 mg/kg of CEPC. CEPC promoted B-cell proliferation at 200 mg/kg treatment when cells were stimulated with lipopolysaccharides but did not promote T-cell proliferation at three doses of CEPC treatment on concanavalin A stimulation.

Polygonum cuspidatum, known by the common name Japanese knotweed, is a tall, stout herbaceous perennial (Seiger, 2005) and is a member of the Polygonaceae (Seiger, 2005).  In China it is referred to as Hu Zhanz.  Japanese knotweed is also known under the scientific names Fallopia japonica and Reynoutria japonica.  The leaves are alternately arranged and are oval with pointed tips and a truncate base.  They measure approximately 15 cm long by 7.5-10 cm wide (Remaley, 2005).  Clusters of tiny white flowers are produced in the late summer, though reproduction is generally through rhizome rather than seed production (Weston et al, 2005). Knotweed is native of China, North and South Korea as well as Japan (Seiger, 2005). Outside of its point of origin, Japanese knotweed was introduced as an ornamental plant Remaley, 2005).  It is widely distributed across the United States and Canada and is found especially along rivers.  It has become established as an invasive species across Eastern Europe, Great Britain and parts of the United States (Seiger, in 1997) including Massachusetts, Connecticut, and California (USDA, 2009).

Because of its presence in China, it has been mainly used primarily in Traditional Chinese Medicine as well as in Asian cultures. The rhizome has been used as an anti-inflammatory, anti-tussitive, diuretic, emmenagogue, emollient, febrifuge, stomachic (Duke & Ayensu, 1985; Usher, 1974). Extracts of the plant have shown antitumor activity within Traditional Chinese Medicine (Duke & Ayensu, 1985).
Japanese knotweed contains compounds that are part of a group of organic chemicals called stilbenes, which are polyphenolic compounds attached by an ethylene (Vastano et al., 2000). The specific composition is dependent on the side chains.  One common stilbene found in Japanese knotweed is resveratrol, which is 3,5,4'-Trihydroxystilbene. Resveratrol has two isomers: cis and trans, with the latter being the most abundant.  Piceid, also known polydatin, is a glucoside form of resveratrol found in Japanese knotweed.  Emodin is an anthraquinone derivative that occurs in extracts of knotweed (Vastano et al., 2000) and other plant species. 

Resveratrol has been shown to have numerous effects, as assessed both in vitro and in vivo.  It decreases the viscosity of the blood and act as anticoagulant to thin blood.  Human blood was used for in vitro analysis, while rabbits were used for in vivo analysis.  This study showed that this property of resveratrol allows it to be effective in treating cardiovascular disease by reducing thrombosis and embolisms that can block arteries and lead to myocardial and cerebral infarctions (Wang et. al, 2002).  Resveratrol was successfully able to decrease platelet aggregation in patients that were resistant to aspirin.  This in vitro study showed that resveratrol could be used to help treat these high risk vascular patients (Gyorgyi, 2006).     

Resveratrol can also provide inflammation relief when used in therapeutically effective amounts and combined with Devil's claw, grapeskin, and syzygium (Charters et al, 2003).  Research shows that extracts from P. cuspidatum inhibits inflammation in mouse ears in response to a topical application of 12-O- tetradecanoylphorbol-13-acetate (TPA) by inhibiting the development of edema and neutrophil infiltration, which is an essential part of the immune response.  The extract at the doses of 2.5, 1.25, and 0.3 milligrams was found to be as effective as indomethacin, a non-steroidal anti-inflammatory drug, at reducing edema (Bralley et. al, 2008).  Edema can lead to more serious complications such as congestive heart failure, so any alleviation is beneficial.
Resveratrol has been found to reduce the tumor volume, tumor weight, and lung metastasis at doses of 2.5 and 10 mg/kg in mice with highly metastatic lung carcinoma (LLC) tumors (Kimura, 2001). The inhibitory effects could not be explained by a natural killer or cytotoxic T-lymphocyte activation. Research suggests that the anti-tumor activities of resveratrol could be caused by the inhibition of DNA synthesis in LLC cells (Kimura, 2001).  High doses of resveratrol have also been shown to inhibit cyclooxygenase expression in human uterine cancer cells in vitro.  Cyclooxygenase is over expressed in endometrial cancer cells and makes these cells resistance to apoptosis (Sexton, 2006).  Resveratrol caused apoptosis in five out of the six cell lines used by inhibiting the cyclooxygenase protein.  Breast cancer metastasis was slowed down using human cell cultures with high doses of resveratrol by inhibiting lamellipodia extension (Azios, 2009).  This property of resveratrol makes it a potential preventative agent of breast cancer.  Low doses, however, have shown to increase metastasis and migration (Azios, 2009).           

Resveratrol is a phytoestrogen and acts as an agonist to estrogen receptors in the body.  Resveratrol has been shown to inhibit estradiol by binding to the estrogen receptors in vitro and activate the transcription reporter cells that are characteristic of the estrogen response (Gehm, 1997).  An in vivo study conducted on rats show that there is no agonism to estrogen receptors on various target tissues, and has been shown to be an estrogen antagonist by not allowing estrogen to lower cholesterol (Turner 1999).      

Many different doses of trans-resveratrol are available commercially, ranging from 20mg to 500mg.  Cis-resveratrol is not commercially available because of little research on the effectiveness of the compound (Orallo, 2006).  Japanese knotweed is included in several herbal preparations that contain other plants that have shown therapeutic success.  One of these compositions is an herbal for alleviating menstrual discomfort, comprising therapeutically effective amounts of Japanese knotweed, chaste tree berry, Mexican wild yam, dandelion, Devil's claw, grapeskin, and syzygium (Charters et al, 2003).  Another herbal composition is used for soothing muscles and joints, comprising of therapeutically effective amounts of Japanese knotweed, N-acetyl D-glucosamine, chondroitin sulfate, D-glucosamine hydrochloride, methylsulfonylmethane, grapeskin, syzygium, and Devil's claw (Charters et al, 2003).  No severe adverse reactions have been identified even when taken in large doses (Udenigwe, 2008).

Other compounds found in Japanese knotweed, including polydatin (piceid) and emodin have been examined for their therapeutic value.  Standard preparations of polydatin include 5, 10, and 25 mg tablets.  Studies have shown that polydatin has lipid-lowering effect in hamsters (Du, et. al, 2009) and in rabbits (Xing, et. al, 2008).  The results from the clinical trials suggest that polydatin has the potential to develop a hypolipemic agent to reduce lipid composition in the blood and/or to serve as a hepatoprotective drug.

Emodin has been shown to selectively inhibit casein kinase II by working as a competitive inhibitor against ATP.  Casein kinase II, a ser/thr protein kinase, is an important enzyme in signal transduction pathways in cell proliferation and differentiation (Yim, 1999).  Inhibiting this kinase would stop the transduction of the signal and the pathway would stop.        
Polygonum cuspidatum has many different positive medicinal uses, mainly from the stilbene compound, resveratrol, and its derivatives. Severe side effects directly from the derivatives of the plant, which are unknown, make it a useful herbal remedy.  The various research investigations on Japanese knotweed had a common thread of helping treat common ailments, such as decreasing cardiovascular disease and as an anticancer agent. These treatments can ultimately lead to an extended lifespan, which other research suggests (Valenzano et al, 2006).

Azios, N., L. Krishnamoorthy, M. Harris, L. Cubano, M. Cammerz, & S. Dharmawardhane. 2009. Estrogen and resveratrol regulate Rac and Cdc42 signaling to the actin cytoskeleton of metastatic breast cancer cells. Neoplasia. 9, 147–158.
Bralley, E., P. Greenspan, J. Hargrove, L. Wicker, & D. Hartle. 2008. Topical anti-inflammatory activity of Polygonum cuspidatum extract in the TPA model of mouse ear inflammation. J Inflamm (Lond). 5: 1
Charters, A., J. Selander, S. Morris, R. Thompson, & L. Blackner. 2003  US Patent 6541945.  Herbal composition and method for combating inflammation. 
Courtney, J.  2002.  Japanese Knotweed (Mexican Bamboo).  Invasive Exotics.  Bowman’s Hill Wildflower Preserve.  
Du, J. L.X. Sun, W. Huang, B. Jia, M. Wu, J. Zhang, & L. Qin. 2008. Lipid lowering effects of polydatin from Polygonum cuspidatum in hyperlipidemic hamsters. Phytomedicine 16: 652-658. 
Duke. J.A. & E.S. Ayensu. 1985. Medicinal Plants of China. Reference Publications, Inc. 
Gehm, B., J. McAndrews, P. Chien, & J. Jameson.1997. Resveratrol, a polyphenolic compound found in grapes and wine, is an agonist for the estrogen receptor. Proc. Natl . Acad. Science. USA 94: 14138 –14143.
Gyorgyi, S., A. Csiszar, K. Lerea, Z. Ungvari, & G. Veress. 2006. Resveratrol inhibits aggregation of platelets from high-risk cardiac patients with aspirin resistance. Journal of Cardiovascular Pharmacology.  48: 1-5.

Jackson, D.  2008.  Japanese and Giant Knotweed.  Fact Sheet: Invasive Weeds.  Penn State College of Agricultural Sciences, Cooperative Extension-Centre County.
Kimura, Y, & H. Okuda. 2001. Resveratrol isolated from Polygonum cuspidatum root prevents tumor growth and metastasis to lung and tumor-induced neovascularization in Lewis lung carcinoma-bearing mice. Journal of Nutrition. 131:1844-1849.
Orallo, F. 2006. Comparative studies of the antioxidant effects of cis- and trans-resveratrol. Curr Med Chem.  13(1): 87-98.
Remaley, T.  2005. Fact Sheet: Japanese Knotweed.  Plant Conservation Alliance’s Alien Plant Working Group.  http://www.nps.gov/plants/ALIEN/fact/pocu1.htm.
Seiger L. 1997.  Mechanical control of Japanese knotweed (Fallopia japonica [Houtt.] Ronse Decraene): Effects of cutting regime on rhizomatous reserves. Natural Areas Journal. 17; 341-345.
Turner, R., G. Evans, M. Zhang, A. Maran, & J. Sibonga. 1999. Is resveratrol an estrogen agonist in growing rats? Endocrinology. 140: 50-54.
Udenigwe, C., V. Ramprasath, R. Aluko, & P. Jones. 2008. Potential of resveratrol in anticancer and anti-inflammatory therapy.  Nutrition Reviews. 66: 445–454.
United States Department of Agriculture. Plants profile: Polygonum cuspidatum. http://plants.usda.gov/java/nameSearch?keywordquery=polygonum+cuspidatum&mode=sciname&submit.x=0&submit.y=0.
Usher. G. 1974. A Dictionary of Plants Used by Man. Constable, London. 1974. 619 p.
Vastano B., Y. Chen, N. Zhu, C. Ho, Z. Zhou, & R. Rosen. 2000.  Isolation and identification of stilbenes in two varieties of Polygonum cuspidatum.  J. Agric. Food Chem. 48;253-256.
Wang, Z., Y. Huang, J. Zou, K. Cao, Y. Xu, & J.M. Wu.  2002.  Effects of red wine and wine polyphenol resveratrol on platelet aggregation in vivo and in vitro. International Journal of Molecular Medicine  9:  77-79.
Weston L, J. Barney, & A. DiTommaso. 2005. A review of the biology and ecology of three invasive perennials in New York State: Japanese knotweed (Polygonum cuspidatum), mugwort (Artemisia vulgaris), and pale swallow-wort (Vincetoxicum rossicum).  Plant and Soil. 277: 53-69. 
Yim, H., Y.H. Lee, C.H. Lee, & S.K. Lee. 1999. Emodin, an anthraquinone derivative isolated from the rhizomes of Rheum palmatum, selectively inhibits the activity of casein kinase II as a competitive inhibitor. Planta medica. 65: 9-13. 
Xing, W., J. Wu, M. Jia, H. Zhang, & L. Qin. 2008. Effects of polydatin from Polygonum cuspidatum on lipid profile in hyperlipidemic rabbits.  Biomedicine & Pharmacotherapy. Jul 9. 

The knotweed plant was prized for its decorative qualities upon its early trade from Asian to European countries in the 1800s. It's now highly valued for its medicinal qualities. The herb has the ability to outgrow and suffocate the growth of other plants. Notwithstanding its invasive nature, the supplement form of the herb has gained increasing popularity as a potent antioxidant and cardiovascular system tonic and Lyme's disease treatment.

The knotweed plant has many varieties. Japanese knotweed, also known a polygonum cuspidatum, is the most commonly encountered and the variety most studied for its healing potential, but other knotweeds such as the Chinese knotweed offer some medicinal benefit as well. The knotweed plant, according to the Invasive Plant Atlas of New England, also goes by the common names Mexican bamboo and fleece flower. It's described as a perennial plant that appears woody in texture and can grow to be 3 to 10 feet in height. The plant produces a flower that appears from August to September, as well as a fruit. The plant, native to Japan and other Asian countries, was brought to the U.S. through Britain. It was distributed for its ornamental properties but was soon despised due to its rampant reproduction and ability to starve the growth of other nearby plants.

Resveratrol is an isolated substance known as a polyphenol that can be extracted from the knotweed plant. Resveratrol can be isolated from red grapes and peanuts, but the Oregon State Linus Pauling Institute notes that the knotweed plant is the greatest source of resveratrol. Most resveratrol supplements sold in the U.S. are extracted from this herb. Resveratrol has great potential as a cardioprotective, cancer-preventive and anti-aging supplement.

Japanese Knotweed and Lyme's Disease
Although knotweed populates many areas of the world, its most concentrated growth is in areas with a high Borrelia infestation, according to the Invasive Plant Atlas of New England. This herbal supplement is considered a mainstay remedy in Stephen Harrod Buhner's Lyme's disease protocol, notes Scott Forsgren, interviewer for the Public Health Report website. Borrelia is the microorganism that causes Lyme's disease. 

Lyme's disease is often effectively treated with conventional antibiotics in its early and acute forms. But as the disease becomes chronic, it's commonly held that the microorganism hides in many areas of the body, such as the nervous system. The Borellia spirochete's metabolites are toxic to the neurological system, and supplements of Japanese knotweed herb appear to cross the blood brain barrier to act as an effective antibacterial and toxin-binding substance. The Public Health Report adds that Japanese knotweed can help with Lyme's-related arthritis symptoms.

Chinese Knotweed Supplements
The Chinese knotweed plant supplement also goes by the name of Fo-Ti or He Shou Wu. This supplement is sold individually and often accompanies many hair-growing products; one of its suggested properties is its ability to potentially reverse prematurely graying hair. The Herbal Resource notes that its other anti-aging properties include its use in Traditional Chinese Medicine patent remedies for diseases such as Alzheimer's disease. Its rejuvenating abilities are coupled with laxative, immune-boosting and fertility-enhancing properties.

Suggested Dosing
Chinese knotweed supplements are recommended in doses between 8g and 25g per day, or as a tea, according to the Herbal Resource Guide. The Public Health Report notes that Japanese knotweed is the premier herb for Lyme's disease. It's suggested as a full-spectrum herb, meaning in its whole root form, in doses of 500mg to 2000mg three to four times per day for eight to 12 months. There may be benefits within two weeks to two months, according to the Public Health Report.

Side Effects
The Herbal Resource Guide notes that Chinese knotweed supplement can be sold in crude or unprocessed forms, as well as those forms that have undergone processing. The unprocessed forms exhibit more of the laxative qualities than the processed forms, and side effects of the supplement may be abdominal upset or loose stools. The Public Health Report says Japanese knotweed should not be used by pregnant women and may lead to a metallic taste in the mouth. The Oregon State University monograph on the concentrated knotweed supplement, resveratrol, notes that a single dose of up to 5g per day has not been found to cause any side effects. It is also not suggested for use in pregnant or lactating women, or in people with estrogen-sensitive cancers because of lack of evidence to prove safety. The herb may interact with several medications, such as blood thinners and drugs metabolized by the P-450 enzyme system in the liver.