Polygonum Multiflorum Thunb Research Articles

Protective effect of Polygonum multiflorum Thunb on amyloid β-peptide 25-35 induced cognitive deficits in mice

Amyloid β protein (Aβ) may be neurotoxic during the progression of Alzheimer's disease by eliciting oxidative stress. This study was designed to determine the effect of Polygonum multiflorum Thunb water extract (PWE) on Aβ25-35-induced cognitive deficits and oxidative stress in mice. Mice were fed experimental diets comprising either 0.5 or 1% PWE for 4 weeks, and then received a single intracerebroventricular (i.c.v.) injection of Aβ25-35 (10μg/mouse). Behavioral changes in the mice were evaluated using passive avoidance and water-maze tests. The consumption of PWE significantly ameliorated the cognitive deficits caused by i.c.v. injection of Aβ25-35. The Aβ25-35 treatment accelerated the lipid peroxidation, and PWE attenuated the Aβ-induced increase in brain levels of thiobarbituric acid reactive substances. There was an increase in glutathione peroxidase activity in PWE-treated groups. The acetylcholinesterase activity in the brain and serum was lower in PWE supplemented groups than in the only Aβ-injected group. These findings suggest that PWE exerts a preventive effect against cognitive deficits induced by Aβ25-35 accumulation in Alzheimer's disease, and that this effect is mediated by the antioxidant properties of PWE.

A systematic survey of antioxidant activity of 30 Chinese medicinal plants using the ferric reducing antioxidant power assay

The antioxidant activities and total phenolic contents of 30 Chinese medicinal plants were evaluated using the ferric reducing antioxidant power assay and the Folin–Ciocalteu method, respectively. The Chinese medicinal plants were extracted by the traditional method, boiling in water and also in 80% methanol. A significant and linear correlation coefficient between the antioxidant activity and the total phenolic content was found in both aqueous ( R 2 = 0.7917) and methanol ( R 2 = 0.7584) extracts. Phenolic compounds are thus a major contributor of antioxidant activity. Comparing the extraction efficiency of the two methods, the boiling water method extracted phenolic compounds more efficiently, and antioxidant activity of the extract was higher. It was found that the Chinese medicinal plants Rhodiola sacra Fu, the stem of Polygonum multiflorum Thunb. and the root of P. multiflorum Thunb. possessed the highest antioxidant activities and thus could be potential rich sources of natural antioxidants.

Study on the Adsorptive Catalytic Voltammetry of Emodin at a Carbon Paste Electrode

An extremely sensitive catalytic voltammetric peak of Emodin at −0.59 V (vs. SCE) was obtained in 0.40 M NH4Cl–NH3 · H2 O buffer (pH 8.2) in the presence of dissolved oxygen at a carbon paste electrode (CPE). The experimental results showed that Emodin was efficiently accumulated at a CPE by adsorption. In the following potential scan, Emodin was reduced to homologous anthrahydroquinone compound, then the compound was immediately oxidized to Emodin by the dissolved oxygen in the solution, and the Emodin was again reduced at the CPE. As a result, a cyclic catalytic reaction was established. At the optimal conditions, the peak current is linearly proportional to the Emodin concentration in the range of 3.0×10−10 M∼4.0×10−9 M (accumulation 70 s) and 4.0×10−9 M∼4.0×10−8 M (accumulation 30 s). The detection limit is 1.0×10−10 M for a 90 s accumulation. The proposed method was successfully applied to determine Emodin in Polygonum multiflorum Thunb. The results are consistent with results obtained by HPLC.

Micropropagation of Polygonum multiflorum THUNB and quantitative analysis of the anthraquinones emodin and physcion formed in in vitro propagated shoots and plants.

An efficient and rapid protocol for in vitro induction and complete plant regeneration of Polygonum multiflorum THUNB has been developed. Nodal explants were grown in vitro on Murashige and Skoog's (MS) basal medium containing different concentrations of alpha-naphthaleneacetic acid (NAA) and benzyladenine (BA). The nodal explants (97%) produced multiple shoots (4.7 shoots per explant) on MS basal medium supplemented with 0.2 mg/l NAA and 2.0 mg/l BA after 6 weeks of culture. Eighty-eight percent to 100% of the shoots (1.0 cm in length) elongated (about 3.02-4.28 cm) and rooted on MS basal medium supplemented with NAA or indole-3-butyric acid (IBA). All the rooted shoots were transferred to pots containing autoclaved soil, vermiculite, and peat moss (1 : 1 : 1). The plantlets were successfully acclimatized under greenhouse conditions with high humidity before transferring to the field. The anthraquinone contents were determined using HPLC. Analysis revealed that the contents of the major medicinal compounds-emodin and physcion in the 6 weeks old in vitro grown shoots and three month old in vitro propagated plants grown in greenhouse were higher than those of the marketed crude drug (processed underground or stem parts of P. multiflorum).

Beneficial Effects of Different Polygonum multiflorum Thunb. Extracts on Memory and Hippocampus Morphology

Four groups of 1-mo-old male senescence-accelerated mice (SAMP8) were fed Polygonum multiflorum Thunb. (PM) extract for 18 wk to determine the effect of PM on memory ability and histopathological changes in mice. The baseline diet consisted of a casein diet group, and the three test diets were supplemented with 50% ethanol, 95% ethanol, or water extracts of PM. It was found that the mice fed with PM extracts had better active shuttle avoidance response, fewer vacuole numbers, less lipofuscin in the hippocampus, and lower MDA concentrations in the brain. Our data showed that the ethanol PM extract groups (both 50% and 95% groups) had lower lipofuscin percentages and MDA concentrations, and higher total thiol concentrations than the water PM extract group. The 50% ethanol PM extract group showed significantly lower total cholesterol and triglyceride values than the other groups, but the HDL cholesterol level was the same. These results suggest that dietary supplementation with either ethanol or water extracts can reduce brain pathological changes and promote learning and memory ability. The performance of PM extracts depended on the extraction method, with ethanol extraction tending to obtain better results.

Flavonoid chemistry and chromosome numbers of Fallopia section Pleuropterus (Polygonaceae)

Flavonoid chemistry and chromosome numbers of Fallopia sect. Pleuropterus were examined to gain insights into the relationships among the taxa within the section. Twenty-seven flavonoid compounds were isolated and identified from taxa of section Pleuropterus; most of them were glycosylated derivatives of the flavonols kaempferol, quercetin, and myricetin, and of the flavones apigenin and luteolin. The flavonoid data appear to be useful for taxon delimitation, because all taxa examined are readily distinguished by their flavonoid profiles. In addition, the flavonoid data revealed the presence of two chemical entities in the section; the first group includes Fallopia multiflora (Thunb. ex Murray) Haraldson (with varieties) and Fallopia ciliinervis (Nakai) Hammer and the second group includes Fallopia baldschuanica (Regel) Holub and Fallopia koreana Oh & Kim. These groupings suggested by the flavonoid chemistry are well-corroborated by the chromosome number of these taxa. Taxa of the first group have chromosome numbers based on x = 11 (2n = 22, 44), whereas chromosome numbers of the second group are based on x = 10 (2n = 20). Our counts for F. multiflora var. hypoleuca (Nakai ex Ohwi) Yonekura & H. Ohashi (2n = 44), Polygonum multiflorum Thunb. ex Murray (= F. multiflora) var. angulatum S.Y. Liu (2n = 22), F. ciliinervis (2n = 22), and F. koreana (2n = 20) are the first reports for these taxa. Based on these results, and in conjunction with morphological evidence, it is strongly suggested that the two groups of section Pleuropterus revealed by this study are not closely allied and may represent separate lineages in the genus Fallopia.Key words: Polygonaceae, Fallopia sect. Pleuropterus, flavonoids, chromosome number, chemotaxonomy.

Flavonoid chemistry and chromosome numbers of <i>Fallopia</i> section <i>Pleuropterus</i> (Polygonaceae)

Flavonoid chemistry and chromosome numbers of Fallopia sect. Pleuropterus were examined to gain insights into the relationships among the taxa within the section. Twenty-seven flavonoid compounds were isolated and identi- fied from taxa of section Pleuropterus; most of them were glycosylated derivatives of the flavonols kaempferol, quercetin, and myricetin, and of the flavones apigenin and luteolin. The flavonoid data appear to be useful for taxon delimitation, because all taxa examined are readily distinguished by their flavonoid profiles. In addition, the flavonoid data revealed the presence of two chemical entities in the section; the first group includes Fallopia multiflora (Thunb. ex Murray) Haraldson (with varieties) and Fallopia ciliinervis (Nakai) Hammer and the second group includes Fallopia baldschuanica (Regel) Holub and Fallopia koreana Oh & Kim. These groupings suggested by the flavonoid chemistry are well-corroborated by the chromosome number of these taxa. Taxa of the first group have chromosome numbers based on x =1 1 (2n = 22, 44), whereas chromosome numbers of the second group are based on x =1 0 (2n = 20). Our counts for F. multiflora var. hypoleuca (Nakai ex Ohwi) Yonekura & H. Ohashi (2n = 44), Polygonum multiflorum Thunb. ex Murray (© F. multiflora )v ar.angulatum S.Y. Liu (2n = 22), F. ciliinervis (2n = 22), and F. koreana (2n = 20) are the first reports for these taxa. Based on these results, and in conjunction with morphological evidence, it is strongly suggested that the two groups of section Pleuropterus revealed by this study are not closely allied and may represent separate lineages in the genus Fallopia.

2,2-Diphenyl-1-picrylhydrazyl radical-scavenging active components from Polygonum multiflorum thunb.

An activity-directed fractionation and purification process was used to identify the antioxidative components of Polygonum multiflorum Thunb. (PM). Dried root of PM was extracted with 95% ethanol and then separated into water, ethyl acetate, and hexane fractions. Among these only the ethyl acetate phase showed strong antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test when compared with water and hexane phases. The ethyl acetate fraction was then subjected to separation and purification using silica gel column chromatography and Sephadex LH-20 chromatography. Three compounds showing strong antioxidant activity were identified by spectral methods ((1)H NMR, (13)C NMR, and MS) and by comparison with authentic samples to be gallic acid, catechin, and 2,3,5, 4'-tetrahydroxystilbene 2-O-beta-D-glucopyranoside.

Myocardial protective effect of an anthraquinone-containing extract of Polygonum multiflorum ex vivo.

An ethyl acetate extract of Polygonum multiflorum Thunb. (PME) was fractionated into an anthraquinone-containing (PME-I) and a non-anthraquinone-containing (PME-II) fraction. The effects of PME and its related extracts pretreatment on myocardial ischemia-reperfusion (IR) injury in isolated perfused rat hearts were examined. Pretreatment with PME extract or its anthraquinone-containing fraction produced a dose-dependent protection against myocardial IR injury, as evidenced by a significant decrease in the extent of LDH leakage as well as an improvement in contractile force recovery. The myocardial protection was found to be associated with an enhancement in myocardial glutathione antioxidant status, as indicated by significant reductions in both the extent of IR-induced reduced glutathione (GSH) depletion and inhibition of Se-glutathione peroxidase (GPX) and glutathione reductase (GRD) activities. Both alpha-tocopherol acetate (VE) and emodin (EMD) pretreatments protected against IR-induced myocardial injury as assessed by the decrease in the extent of LDH leakage. But the contractile force recovery of the ischemic-reperfused hearts prepared from VE or EMD pretreated animals was not improved. The more complete myocardial protection afforded by the anthraquinone-containing fraction of PME extract may be related to its ability to sustain the glutathione antioxidant status under the condition of IR-induced oxidative stress.

Antioxidant activities of Polygonum multiflorum Thunb., in vivo and in vitro

We have demonstrated the presence of both in vivo and in vitro antioxidant activities in the crude water-extract of the root of Polygonum multiflorum Thunb. (PMC), as indicated by its ability to protect against CCl4-induced hepatotoxicity in rats and to scavenge ferri-heme oxidants generated in an in vitro system. Activity-directed fractionation of the PMC indicated that the antioxidant components were contained in the ethylacetate fraction.

Partial nodular transformation of the liver with patent ductus venosus: J.S. Lentz, I.R. Wanless, E.A. Roberts, Dept. of Pathology, Toronto Western Hospital, and Division of Gastroenterology, Hospital for Sick Children, University of Toronto, Toronto, M5T 2S8

Polygonum multiflorum Thunb.(PM), (known as Heshouwu (何首乌) in China) is one of the most important and well mentioned Chinese medicinal herbs in the literature for its use in blackening hair, nourishing liver and kidney, anti-aging, anti-hyperlipidemia, antioxidant, anti-inflammatory, anticancer, hepatoprotection, cardio-protection and improving age-related cognitive dysfunction. The purpose of this review is to give a comprehensive and recent update on PM: new compounds or isolated for the first time, potential hepatotoxic compounds and their mechanisms. Moreover, future perspectives and challenges in the future study of this plant are conversed which will make a new base for further study on PM.A comprehensive review of relevant published literature on PM using the scientific databases SCOPUS, PubMed, and Science Direct was done.PM is broadly produced in many provinces of China and well known in other Eastern Asian Countries for its ethno-medical uses. Previous phytochemical investigation of PM had led to the isolation of more than 175 compounds including recently isolated 70 new compounds. Most of the new compounds isolated after 2015 are majorly dianthrone glycosides and stilbene glycosides. Processing has also a significant effect on chemical composition, pharmacological activities, and toxicity of PM. PM-induced liver injury is increasing after the first report in Hong Kong in 1996. Hepatotoxicity of PM was constantly reported in Japan, Korea, China, Australia, Britain, Italy, and other countries although its toxicity is related to idiosyncratic hepatotoxicity. More interestingly, although there is indispensable interest to predict idiosyncratic hepatotoxicity of PM and understand its mechanisms, the responsible hepatotoxic compounds and mechanisms of liver damage induced by PM are still not clear. There is a big controversy on the identification of the most responsible constituent. Anthraquinone and stilbene compounds in PM, mainly emodine and TSG are mentioned in the literature to be the main responsible hepatotoxic compounds. However, comparing the two compounds, which one is the more critical toxic agent for PM-induced hepatotoxicity is not well answered. Affecting different physiological and metabolic pathways such as oxidative phosphorylation and TCA cycle pathway, metabolic pathways, bile acid excretion pathway and genetic polymorphisms are among the mechanisms of hepatotoxicity of PM.Deeper and effective high throughput experimental studies are still research hotspots to know the most responsible constituent and the mechanism of PM-induced hepatotoxicity.

Mutagenic Activity of Ho Shao Wu (Polygonum Multiflorum Thunb.)

Forty samples of Polygonum multiflorum Thunb were tested by the Ames Salmonella/Microsome assay. The results revealed that the herb is not mutagenic.