Cardioprotective effect of polydatin against ischemia/reperfusion injury: roles of protein kinase C and mito K(ATP) activation

Polydatin preconditioning (PPC) has been reported to be protective against brain and intestine ischemia/reperfusion injury (I/R injury), but whether polydatin exerts cardioprotective effect against myocardial ischemia/reperfusion and the underlying mechanisms remain unclear. Previous studies have demonstrated that oxidative stress plays an important role in the process of I/R. Elevation of oxidative agents and decline in anti-oxidant substance would promote I/R. Meanwhile, the activation of PKC signaling seems to mediate the cardioprotective effects of many drugs by alleviating Ca(2+) influx. In the present study, we reported for the first time that intravenous administration of polydatin before I/R significantly limited the infarct size, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) leakage from the damaged myocardium after I/R. The activity of SOD and the content of MDA remarkably changed in the presence of polydatin as well. However, the cardiac function-preserving and myocardial enzymes leakage-limiting effects of polydatin vanished in the presence of PKC inhibitors and mito K(ATP) channel blockers. But there was not a significant change in the activity of SOD and MDA content. We therefore conclude that PPC exerts cardioprotective effect by the activation of PKC-K(ATP)-dependent signaling and the direct anti-oxidative stress mechanisms.

Combined phytochemistry and chemotaxis assays for identification and mechanistic analysis of anti-inflammatory phytochemicals in Fallopia japonica

Plants provide a rich source of lead compounds for a variety of diseases. A novel approach combining phytochemistry and chemotaxis assays was developed and used to identify and study the mechanisms of action of the active compounds in F. japonica, a medicinal herb traditionally used to treat inflammation. Based on a bioactivity-guided purification strategy, two anthranoids, emodin and physcion, were identified from F. japonica. Spectroscopic techniques were used to characterize its crude extract, fractions and phytochemicals. The crude extract, chloroform fraction, and anthranoids of F. japonica significantly inhibited CXCR4-mediated chemotaxis. Mechanistic studies showed that emodin and physcion inhibited chemotaxis via inactivating the MEK/ERK pathway. Moreover, the crude extract and emodin could prevent or treat type 1 diabetes in non-obese diabetic (NOD) mice. This study illustrates the applicability of a combinational approach for the study of anti-inflammatory medicine and shows the potential of F. japonica and its anthranoids for anti-inflammatory therapy.

Comparison of the antioxidant and transmembrane permeative activities of the different Polygonum cuspidatum extracts in phospholipid-based microemulsions

The main purpose of this study was to investigate the transmembrane permeability of polyphenol-containing Polygonum cuspidatum extracts (PCE) encapsulated in phospholipid-based o/w microemulsion system. First, preparations of several PCEs using solid- or liquid-phase extraction or a combination of both, as well as evaluation of their antioxidant activities, were conducted and compared. In the antioxidant study, results indicated that PC-1 with the least extraction process exhibited the best antioxidant activity. By comparing the permeability coefficient (K(p)) among all tested PCEs in microemulsions (ME-PCs), ME-PC1 also possessed the largest permeability coefficients of both resveratrol and emodin. In addition, comparison of the transmembrane permeability of several polyphenol-encapsulated microemulsions showed that resveratrol had the most competitive advantage in the microemulsion formula for the control-release process. Taken together, it can be concluded that the matrix removed from the solid-phase extraction in PC-1 not only possesses antioxidant activity but also acts as an enhancer in transmembrane permeation. The structure specificity of the polyphenol plays important roles in the mechanism of the transmembrane permeation process. These findings might provide scientific evidence for the value of developing polyphenol-containing PCEs as nutraceuticals and cosmoceutical products.

A resveratrol and polyphenol preparation suppresses oxidative and inflammatory stress response to a high-fat, high-carbohydrate meal

BACKGROUND

High-fat, high-carbohydrate (HFHC) meals are known to induce oxidative and inflammatory stress, an increase in plasma endotoxin concentrations, and an increase in the expression of suppressor of cytokine signaling-3 (SOCS-3).

HYPOTHESIS

The intake of a nutritional supplement containing resveratrol and muscadine grape polyphenols reduces HFHC meal-induced oxidative and inflammatory stress and stimulates the activity of the antioxidant transcription factor, NF-E2-related factor-2 (Nrf-2), and its downstream targets.

METHODS

Ten normal, healthy subjects were given a 930-kcal HFHC meal either with placebo or with the supplement. Indices of oxidative stress, inflammation, Nrf-2 binding activity, the concentrations of endotoxin (lipopolysaccharide) and lipoprotein binding protein (LBP), and the expression of toll-like receptor 4 (TLR-4), CD14, IL-1β, TNFα, SOCS-3, Keap-1, NAD(P)H:quinone oxidoreductase-1 (NQO-1), and GST-P1 were measured.

RESULTS

The intake of the supplement suppressed the meal-induced elevations of plasma endotoxin and LBP concentrations, the expression of p47(phox), TLR-4, CD14, SOCS-3, IL-1β, and Keap-1, while enhancing Nrf-2 binding activity and the expression of NQO-1 and GST-P1 genes.

CONCLUSION

A supplement containing resveratrol and muscadine polyphenols suppresses the increase in oxidative stress, lipopolysaccharide and LBP concentrations, and expression of TLR-4, CD14, IL-1β and SOCS-3 in mononuclear cells after an HFHC meal. It also stimulates specific Nrf-2 activity and induces the expression of the related antioxidant genes, NQO-1 and GST-P1. These results demonstrate the acute antioxidant and antiinflammatory effects of resveratrol and polyphenolic compounds in humans in the postprandial state.

Protective, antioxidative and antiapoptotic effects of 2-methoxy-6-acetyl-7-methyljuglone from Polygonum cuspidatum in PC12 cells

Much correlative evidence indicates that the oxidative modification of protein by reactive oxygen species (ROS) is involved in normal aging as well as the pathogenesis of neurodegenerative diseases such as Alzheimer's disease. In this study, we explored the antioxidative and neuroprotective effects of a naphthoquinone, 2-methoxy-6-acetyl-7-methyljuglone (MAM), purified from the dried rhizome of POLYGONUM CUSPIDATUM (Chinese name Hu-Zhang). Pretreatments with MAM (24 h) were investigated for their protective effects against apoptosis induced by the oxidizing agent TERT-butyl hydroperoxide ( T-BHP) in PC12 cells. The results indicated that MAM pretreatments could effectively protect PC12 cells against cytotoxicity induced by T-BHP in a dose-dependent manner. Cell viability was determined by both MTT and LDH assays. Increasing concentrations of MAM enhanced cell viability significantly and completely prevented cell death induced by T-BHP at 2.5 µM. The corresponding extracellular lactate dehydrogenase (LDH) levels were also attenuated significantly by various concentrations of MAM. In addition, it was found that the antioxidative effect of MAM was stronger than those of resveratrol and lipoic acid. The antiapoptotic property of MAM was further investigated with Hoechst 33342 nuclear staining and TUNEL assay. Pretreatments of MAM were able to prevent the T-BHP-induced nucleus fragmentation and accumulation of apoptotic bodies (commonly accepted as markers of apoptosis) inside the cells in a dose-dependent manner. T-BHP induced the phosphorylation of ERK 1/2, JNK and p38 MAPK, which were all impeded by pretreatments with MAM, indicating that MAM may act as a potent antioxidant which significantly interferes with the MAPK apoptotic cascades, probably rescuing cells by inhibiting the death pathways.

Quality assessment of Polygonum cuspidatum and Polygonum multiflorum by 1H NMR metabolite fingerprinting and profiling analysis

The quality assessment and control of traditional Chinese medicines (TCM) nowadays receives a great deal of attention worldwide and particularly in Europe with its increasing local use. Polygonum cuspidatum Siebold & Zucc. and Polygonum multiflorum Thunb. are two members of the Polygonaceae family, which are widely used as Chinese medicinal plants. The aim of this study was to achieve an overview of the quality of P. cuspidatum and P. multiflorum samples available on the Chinese market and to identify important metabolites for their discrimination, using (1)H NMR-based metabolomics. (1)H NMR and multivariate analysis techniques were applied to almost 60 plant samples collected in different places in China. Using (1)H NMR metabolomics, it was possible, without previous evaporation or separation steps, to obtain metabolic fingerprints to distinguish between the species. The important metabolites for discrimination were stilbene derivatives. Finally, a clear distinction between the two species was possible and the discriminant metabolites were identified.

[Optimization of ultrahigh pressure extraction for polydatin and resveratrol from Polygonum cuspidatum by using uniform design]

OBJECTIVE

To optimize the ultrahigh pressure extraction (UPE) process of polydatin and resveratrol from Polygonum cuspidatum by using uniform design.

METHOD

On the basis of single factor screening, the uniform design was adopted for getting the optimal technique parameters. The optimum result of UPE was compared with conventional extractions.

RESULT

The optimal conditions of UPE for polydatin and resveratrol were that the solvent was 55% ethanol, the ratio of solvent to material( mL: g) was 30, the extraction pressure was 170 MPa, and the extraction time was 120 second. With this extracting process, the extraction yield of polydatin and resveratrol were 14.29 and 2.53 mg x g(-1), respectively. The extraction yield of polydatin was 46.1% higher than the heat reflux extraction, 6.4% higher than the ultrasonic extraction and 28.5% higher than the microwave extraction, while the yield of resveratrol was 67.5% higher than the heat reflux extraction, 29.7% higher than the ultrasonic extraction and 24.6% higher than the microwave extraction, respectively.

CONCLUSION

As a novel extraction technology for Chinese herbal medicine, the UPE procedure has higher extraction yield, lower extracting temperature, shorter extacting time and less power consumption. The UPE has provided a brand-new method for extraction of polydatin and resveratrol from P. cuspidatum.

An antiinflammatory and reactive oxygen species suppressive effects of an extract of Polygonum cuspidatum containing resveratrol

BACKGROUND

Resveratrol have been shown to exert an antiinflammatory and antiaging effects in vitro and in animal models.

OBJECTIVE

The objective of the study was to investigate the effect of a Polygonum cuspidatum extract (PCE) containing resveratrol on oxidative and inflammatory stress in normal subjects.

RESEARCH DESIGN AND METHODS

Two groups (10 each) of normal-weight healthy subjects were randomized to placebo or PCE containing 40 mg resveratrol daily for 6 wk. Fasting blood samples were obtained prior to and after treatment at 1, 3, and 6 wk. Mononuclear cells were prepared for reactive oxygen species generation, RNA isolation, nuclear extract, and total cell homogenate preparation. Indices of oxidative and inflammatory stress, suppressor of cytokine signaling-3, phosphotyrosine phosphatase-1B, jun-N-terminal kinase-1, and inhibitor of kappaB-kinase-beta were measured by RT-PCR and Western blotting.

RESULTS

The extract induced a significant reduction in reactive oxygen species generation, the expression of p47(phox), intranuclear nuclear factor-kappaB binding, and the expression of jun-N-terminal kinase-1, inhibitor of kappaB-kinase-beta, phosphotyrosine phosphatase-1B, and suppressor of cytokine signaling-3 in mononuclear cells when compared with the baseline and the placebo. PCE intake also suppressed plasma concentrations of TNF-alpha, IL-6, and C-reactive protein. There was no change in these indices in the control group given placebo.

CONCLUSIONS

The PCE-containing resveratrol has a comprehensive suppressive effect on oxidative and inflammatory stress.

Anti-HIV activities of the compounds isolated from Polygonum cuspidatum and Polygonum multiflorum

The 70 % EtOH extract of Polygonum cuspidatum showed inhibitory action against HIV-1-induced syncytium formation at non-cytotoxic concentrations in vitro with a 50 % effective concentration (EC(50)) of 13.94 +/- 3.41 microg/mL. Through bioactivity-guided fractionation, 20 phenolic compounds, including eight stilbenoids, were isolated from the roots of Polygonum cuspidatum, and their anti-HIV-1 activities were evaluated. Results showed that compounds 1, 13, 14, and 16 demonstrated fairly strong antiviral activity against HIV-1-induced cytopathic effects in C8166 lymphocytes at non-cytotoxic concentrations, with EC (50) values of 4.37 +/- 1.96 microg/mL, 19.97 +/- 5.09, 14.4 +/- 1.34 microg/mL, and 11.29 +/- 6.26 microg/mL and therapeutic index (TI) values of 8.12, > 10.02, > 13.89, and > 17.71, respectively. Other compounds showed either weak or no effects. Compound 6 also showed weak inhibition (153.42 +/- 19.25 microg/mL); however, it possesses very good water solubility and showed almost no cytotoxicity (> 2000 microg/mL), therefore achieving a fairly good TI (13.04). The activities of the two compounds (3 and 18) from Polygonum multiflorum were also assayed. The relationship between molecular structures and their bioactivities was also discussed.

[Selective removal of tannins from Polygonum cuspidatum extracts using collagen fiber adsorbent]

OBJECTIVE

To investigate the selective removal of tannins from Polygonum cuspidatum extracts by using collagen fiber adsorbent, and to evaluate the adsorption and desorption performances of collagen fiber adsorbent to tannins.

METHOD

The adsorbent was prepared from bovine skin collagen fiber through crosslinking reaction of glutaraldehyde, and then used for the selective removal of tannins from P. cuspidatum extracts. Gelatin-turbidity method, gelatin-ultraviolet spectrometry method and HPLC were used for detection of tannins in the solutions. Ethanol-water solutions with varying concentration were used to test their desorption ability of tannins in order to choose proper desorption solution. On the basis of batch experimental results, the column adsorption and desorption tests were carried out, by using gelatin-turbidity method for detection of tannins.

RESULT

The collagen fiber adsorbent exhibited excellent adsorption selectivity to tannins. It was found that tannins of P. cuspidatum were completely removed, while nearly no adsorption of active components (resveratrol as representative) was found. Moreover, the collagen fiber adsorbent could be regenerated by using 30% ethanol-water solution and then reused.

CONCLUSION

The collagen fiber adsorbent can be considered as a promising material for selective removal of tannins from P. cuspidatum extracts.

Preformulation stability of trans-resveratrol and trans-resveratrol glucoside (Piceid)

Resveratrol and resveratrol glucoside (piceid) were evaluated in a preformulation stability study. An HPLC assay was used for the analysis of stressed/reference samples. Samples of solid, crystalline material were held under the following conditions: 40 degrees C/75% RH (both open and protected), ambient fluorescent light (open), 70 degrees C (open), and exposed using a light cabinet to achieve ICH conditions for UV/fluorescent light. Both compounds were found to be stable out to 3 months for both accelerated and ambient conditions with negligible degradation. Exposure to UV and fluorescent light under ICH conditions did not significantly degrade the solid materials for UV exposure at 3 times the ICH limit and for fluorescent light exposure at 1 times the ICH limit. The results presented demonstrate crystalline resveratrol and piceid are stable solids. No evidence of oxidation of either material by atmospheric oxidants was seen. The data reported may help to clarify widely held beliefs that resveratrol is unstable and extremely sensitive to oxidation/degradation.

[Identification and determination of major constituents in Polygonum cuspidatum Sieb. et Zucc. by high performance liquid chromatography/electrospray ionization-ion trap-time-of-flight mass spectrometry]

A facile method using high performance liquid chromatography/electrospray ionization-ion trap-time-of-flight mass spectrometry (HPLC/ESI-IT-TOF MS) has been established for the analysis of multiple constituents in Polygonum cuspidatum Sieb. et Zucc. Six chemical standards including emodin, chrysophanol, physcion, rhein, aloe-emodin and polydatin were studied systematically and their fragmentation pathways were concluded. The methanol extract of Polygonum cuspidatum Sieb. et Zucc. was separated and analyzed by HPLC/ESI-QIT-TOF MS system in negative ion mode. A total of 10 constituents were identified or tentatively characterized with supporting results on the fragmentation pathways of 6 chemical standards and relative references. These constituents are mainly anthraquinones, stilbenes, torachryson and their derivatives, including resveratroloside, polydatin, emodin-8-O-glucoside, resveratrol, torachryson-8-O-glucoside, emodin-1-O-glucoside, torachryson-8-O-(6'-acetyl)glucoside (newly discovered), physcion-8-O-glucoside, physcion-8-O-(6'-acetyl)glucoside (newly discovered) and emodin. It is an extremely simple way by using HPLC/ESI-IT-TOF MS to provide chemical information concerning the constituents in herbal medicines and making the identification results more convinced.

Lipid-lowering effects of polydatin from Polygonum cuspidatum in hyperlipidemic hamsters

Hyperlipidaemias are common in obese people, and they increase the risk of cardiovascular diseases such as coronary heart disease (CHD) and atherosclerosis (AS). Previous studies have shown that several drugs can depress serum cholesterol. However, they could cause serious side effects in various clinical settings. The objective of the present study was to evaluate the lipid-lowering effects of polydatin in high-fat/cholesterol (HFC)-fed hamsters. The levels of lipids in hamsters were measured enzymatically before and after the administration of polydatin. Significant differences between HFC and HFC+polydatin were detected for those concentrations. Decreased levels of serum TC, TG and LDL-C and the concentrations of hepatic TG were found. Experimental results also showed that polydatin elevated LDL-C/HDL-C and TC/HDL-C ratios. In concert with other effects, serum cholesterol-lowering effect in hamsters may contribute to the regulation properties attributed to polydatin.

Tissue distribution and excretion of resveratrol in rat after oral administration of Polygonum cuspidatum extract (PCE)

PURPOSE

Polygonum cuspidatum extract as a traditional Chinese medicine is extracted from the dried rhizome and root of Polygonum cuspidatum Sieb.et Zucc. Resveratrol is one of its active components. Studies were performed in rats to define the tissue distribution and excretion of resveratrol in urine and bile, and to characterize (if possible) any metabolites of resveratrol observed in tissues after ig 20mg/kg Polygonum cuspidatum extract.

METHOD

For tissue distribution studies, tissues (300 mg) were homogenized and centrifuged with methanol, and metabolites found in selected tissue extract were identified by LC/MS/MS. For urinary and biliary excretion experiments, urine and bile samples were cleaned up by using solid-phase extraction (SPE) with polyamide cartridges. All the concentrations of resveratrol in these biological samples were determined by HPLC with UV detection.

RESULT

After a single oral dose of 20mg/kg PCE in rats, resveratrol was mainly distributed in stomach, duodenum, liver and kidney with detectable metabolites resveratrol monoglucuronide and resveratrol monosulfate. The majority of the resveratrol was excreted as metabolites, only 0.59% and 0.027% of the dosage were excreted in urine and bile respectively as unchanged drug within 24h.

Polygoni cuspidati radix inhibits the activation of Syk kinase in mast cells for antiallergic activity

The antiallergic activity of Polygoni cuspidati radix (PR) and the mechanism of action by which it functions were investigated in this study. The extract of PR exhibited potent inhibitory activity in mast cells; its IC50 values were 62 +/- 2.1 microg/ml for RBL-2H3 mast cells and 46 +/- 3.2 microg/m for bone marrow-derived mast cells by antigen stimulation, and it also suppressed the expression of tumor necrosis factor-alpha and interleukin-4 in RBL-2H3 cells. According to the in vivo animal allergy model, it inhibited a local allergic reaction, passive cutaneous anaphylaxis, in a dose-dependent manner. With regard to its mechanism of action, PR inhibited the activating phosphorylation of Syk, a key signaling protein for the activation of mast cells. It also suppressed Akt and the mitogen-activated protein kinases ERK1/2, p38, and JNK, which are critical for the production of various inflammatory cytokines in mast cells. The results of the study indicate that the antiallergic activity of PR is mediated through the inhibition of histamine release and allergic cytokine production by the inhibition of Syk activating phosphorylation in mast cells.

Neuroprotective effects of emodin-8-O-β-d-glucoside in vivo and in vitro

Emodin-8-O-beta-D-glucoside extracted from the traditional Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc is widely used to treat acute hepatitis possibly by antioxidative mechanisms. The present study was designed to investigate whether emodin-8-O-beta-D-glucoside exerted neuroprotective effects on the focal cerebral injury induced by ischemia and reperfusion in vivo and on the neuronal damage induced by glutamate in vitro, and to study the possible mechanisms. Male Wistar rats were used to establish the model of ischemia and reperfusion. The behavioral test was performed and the cerebral infarction area was assessed in the brain slices stained with 2% 2,3,5-triphenyl tetrazolium chloride to evaluate the neuroprotective effects of emodin-8-O-beta-D-glucoside. Superoxide dismutase (SOD) activity, total antioxidative capability and malondialdehyde (MDA) level in the brain tissue were determined with spectrophotometrical methods to probe the primary mechanisms of emodin-8-O-beta-D-glucoside. In vitro, the neuroprotective effects of emodin-8-O-beta-D-glucoside were tested in the cultured cortical cells of fetal rats exposed to glutamate. Emodin-8-O-beta-D-glucoside concentration in plasma and brain tissue was also measured to examine distribution of emodin-8-O-beta-D-glucoside in the brain. The results showed that the treatment of rats with emodin-8-O-beta-D-glucoside reduced the neurological deficit score and the cerebral infarction area, increased SOD activity and total antioxidative capability, and decreased MDA level in the brain tissue in dose-dependent way. Emodin-8-O-beta-D-glucoside also inhibited the neuronal damage induced by glutamate. Besides, emodin-8-O-beta-D-glucoside was able to penetrate blood-brain barrier and distribute in the brain tissue. These findings demonstrate that emodin-8-O-beta-D-glucoside is able to provide neuroprotection against cerebral ischemia-reperfused injury and glutamate induced neuronal damage through exerting antioxidative effects and inhibiting glutamate neurotoxicity.

[FTIR spectra-principal component analysis of roots of Polygonum cuspidatum from different areas]

Polygonum cuspidatum Sieb. et Zucc. is an important Chinese traditional medicine, and has wide distribution in China. Based on their infrared fingerprint spectra, Polygonum cuspidatum root samples from 7 geographical origins could be divided into 6 classes with principal component analysis. The classification was well correlated to their geographical origins and weather. In the same class, the chemical components of P. cuspidatum are similar to each other, which can be considered as the criterion for evaluating the quality of P. cuspidatum. The results showed that their characteristic infrared spectra were similar in the range of 4000-1700 cm(-1), but varied significantly for different groups and kinds of P. cuspidatum samples in the range of 1700-900 cm(-1). The method is rapid and simple, and could be applied to evaluate the quality of this traditional Chinese medicine. It is one of the methods in the quality control of traditional Chinese medicines.

Analysis of Rhizoma Polygoni Cuspidati by HPLC and HPLC-ESI/MS

An HPLC method with photodiode array detection (PAD) and ESI/MS detection was developed for the qualitative and quantitative analysis of the major chemical constituents of the dried rhizome of Polygonum cuspidatum Sieb. et Zucc. (Rhizoma Polygoni Cuspidati; Chinese name Hu-Zhang). Based on the chromatographic separation on an Altima C(18) column using 0.5% aqueous acetic acid and acetonitrile as the mobile phase, nine compounds, including stilbenes, stilbene glucosides, anthraquinones and anthraquinone glucosides, were identified by online ESI/MS analysis and seven were quantified by HPLC-PAD. A full validation of the method including sensitivity, linearity, repeatability and recovery was conducted. Linear calibration was achieved over the concentration range 1-200 mg/L with R(2) > 0.999, whilst the limits of detection ranged from 0.51 to 1.57 ng. Repeatability was evaluated by intra- and inter-day assays and the RSD value was within 1.79%. Recoveries of the quantified compounds were within the range 96.0-100.1% with RSD values of less than 2.2%. Five samples of Rhizoma Polygoni Cuspidati from different regions were analysed using the developed method. The major constituents piceid, resveratrol, emodin-8-O-beta-D-glucoside and emodin were selected to provide an index for the quality assessment of the herbal drug.

Polygonum cuspidatum, compared with baicalin and berberine, inhibits inducible nitric oxide synthase and cyclooxygenase-2 gene expressions in RAW 264.7 macrophages

Polygonum cuspidatum water extract (PCWE) was shown to be a potent inhibitor of lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). PCWE was compared to baicalin isolated from Scutellaria baicalensis Georgi and berberine of Coptidis rhizoma and Phellodendri cortex, for their effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. Both PCWE and the compounds inhibited LPS-induced NO production in a concentration-dependent manner without a cytotoxicity. The decrease in NO production was in parallel with the inhibition of LPS-induced iNOS gene expression by PCWE and the compounds. In contrast, iNOS enzyme activity was not inhibited by PCWE and two agents. In addition, only PCWE inhibited LPS-induced prostaglandin E2 (PGE2) production and COX-2 gene expression without affecting COX-2 enzyme activity, while baicalin or berberine did not. Furthermore, N-nitro-L-arginine (NLA) and N-nitro-L-arginine methyl ester (L-NAME) pretreatment enhanced LPS-induced iNOS protein expression, which was inhibited by these PCWE and two agents, although LPS-induced COX-2 protein expression was not affected by NLA and L-NAME. PCWE inhibited PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS-co-treated RAW 264.7 cell, however, baicalin or berberine did not. From the results, it was concluded that co-treatment with NOS inhibitors and PCWE effectively blocks acute production of NO and inhibits expression of iNOS and COX-2 genes.

In vitro effects of a fraction separated from Polygonum cuspidatum root on the viability, in suspension and biofilms, and biofilm formation of mutans streptococci

Polygonum cuspidatum (Polygonaceae) has traditionally been used in folk medicine to control oral diseases. Nevertheless, there are no reports related to its possible effect on the diseases, particularly on biofilm-related diseases such as dental caries. In this study, we evaluated in vitro effects of a fraction separated from Polygonum cuspidatum root on the viability, in both suspension and biofilms, and the biofilm formation of mutans streptococci. The separated fraction (F1) showed bacteriostatic and bactericidal activity against mutans streptococci in suspension, with minimum inhibitory concentration (MIC) range of 31.3-250 microg/ml and minimum bactericidal concentration (MBC) range of 0.5-1 mg/ml. At a concentration of 1.5 mg/ml, F1 killed approximately 2 log(10)CFU/ml of Streptococcus mutans and Streptococcus sobrinus after 2h of exposure. In biofilms, F1 also inhibited the viability of Streptococcus mutans and Streptococcus sobrinus, dependent on the biofilm age, the concentration of F1, and the treatment time. Four hours of exposure to 1.5 mg/ml F1 reduced the viable counts of Streptococcus mutans and Streptococcus sobrinus by greater than 2 log(10)CFU/disc. Furthermore, at sub-MIC levels, F1 inhibited biofilm formation by Streptococcus mutans and Streptococcus sobrinus in a dose-dependent fashion. Based on the preliminary phytochemical analysis, the activity of F1 may be related to the presence of anthraquinones, cardiac glycosides, terpenoids, and phenolics. These results indicate that F1 is probably useful in the control of oral biofilms and subsequent dental caries development.

Antioxidant activity of extract from Polygonum cuspidatum

Numerous diseases are induced by free radicals via lipid peroxidation, protein peroxidation and DNA damage. It has been known that a variety of plant extracts have antioxidant activities to scavenge free radicals. Whether Polygonum cuspidatum Sieb. et Zuce has antioxidant activity is unknown. In this study, dried roots of Polygonum cuspidatum were extracted by ethanol and the extract was lyophilized. Free radical scavenging assays, superoxide radical scavenging assays, lipid peroxidation assays and hydroxyl radical-induced DNA strand scission assays were employed to study antioxidant activities. The results indicate that the IC50 value oí Polygonum cuspidatum extract is 110 microg/ml in free radical scavenging assays, 3.2 microg/ml in superoxide radical scavenging assays, and 8 microg/ml in lipid peroxidation assays, respectively. Furthermore, Polygonum cuspidatum extract has DNA protective effect in hydroxyl radical-induced DNA strand scission assays. The total phenolics and flavonoid content of extract is 641.1 +/- 42.6 mg/g and 62.3 +/- 6.0 mg/g. The results indicate that Polygonum cuspidatum extract clearly has antioxidant effects.

[Effect of different light intensity on Polygonum cuspidatum callus]

OBJECTIVE

To study the effect of light intensity (LI) on the callus induction and resveratrol content of Polygonum cuspidatum.

METHOD

Taking leaves and stem segment of P. cuspidatum as explants, the callus was inducted and cultured under different LI. The growth status of callus was observed and analyzed. The content of resveratrol was determined by HPLC.

RESULT

The formation and growth of the stem segment callus were optimal under low light treatment (1340-1560 lx). The resveratrol content was 18.350 microg x g(-1) in fresh stem segment and 140.074 microg x g(-1) in dry stem segment, which was two times higher than that of wild P. cuspidatum.

CONCLUSION

Introduction and status of P. cuspidatum callus were obvious diverse under different LI, the resveratrol content of P. cuspidatum was enhanced under appropriate LI.

[Study on the stability of resveratrol in rhizoma polygoni cuspidati]

OBJECTIVE

The stability of resveratrol in Rhizoma Polygoni Cuspidati is evaluated all-roundly.

METHODS

We not only increase influence intensity by physical, chemical and biological methods but also parallel analyzing the influence results to elicit the opinions.

RESULTS

The content of resveratrol is declied greatly by lighting, heating, wet-heating or oxidizing. The content is increased in Rhizoma Polygoni Cuspidati treated with acid or alkali only using sodium hydroxide until pH=11. The content is not increased when its own activated microbe is destroyed.

CONCLUSION

Resveratrol is unstable against light, heat, wet-heating and oxidizer. Its own activated microbe has not influenced to it. It has not benefit with acidification. Its solubility and stability increase formed sodium salt with basification.

[Application of macroporous resin in purification for effective part from Polygonum cuspidatum]

OBJECTIVE

To study the technological parameters of the purification process for effective part from Polygonum cuspidatum.

METHOD

Using adsorption capacities and desorption rates of polydatin, resveratrol,emodin,physcion and total anthraquinone as the primary screening indexes, six resins were surveyed,and the optimized conditions of adsorption and desorption of the effective ingredients were studied.

RESULT

Resin D101 gave good separation performance and was selected to purify the effective part in Polygonum cuspidatum. The optimum parameters were established as the following: 1 BV (bed volume) sample extract was passed through the column with a flow rate of 2.4 BV x h(-1), 30 min later,the column was washed with 2 BV water, 2 BV 20% ethanol, 5 BV 50% ethanol, 2 BV 70% ethanol and 5 BV 95% ethanol, respectively. The combined 50% and 95% ethanolic elutes were concentrated to yield the purified effctive part.

CONCLUSION

The purity of the total effective ingredients in the product was up to 36. 87%. Macroporous resin D101 could be well used in separating and purifying the effective part from Polygonum cuspidatum.

An effective sample preparation approach for screening the anticancer compound piceatannol using HPLC coupled with UV and fluorescence detection

Piceatannol, compared with the renowned resveratrol, is a better anticancer agent and a superior agent with other biological activities. However, as there are only few plants reported to contain minute quantity of piceatannol, the scarcity of sources greatly impedes the piceatannol-related researches. To explore new sources of piceatannol, we established a sample preparation approach for screening the piceatannol in plants using HPLC-UV-fluorescence detection. When the HPLC is coupled with UV and fluorescence detectors, the decrease of signals in interferences and increase of signal in piceatannol in the fluorescence chromatogram mark clearly the position of the piceatannol peak; ultimately, it allows identification without standards. In this study, we systematically evaluated the factors affecting the extraction efficiency of piceatannol in sample preparation. Of the sample preparation strategies studied, direct solvent extraction and liquid nitrogen treatment followed by solvent extraction gave satisfactory recoveries for both piceatannol and resveratrol. These approaches avoided time-consuming lyophilization procedure. In addition, all procedures must be done in the dark to avoid negative impact of irradiation from fluorescence light on the recoveries of piceatannol and resveratrol. With the present method, we re-examined the plants previously claimed to contain only resveratrol for their piceatannol contents. The species examined included Polygonum cuspidatum, Arachis hypogaea, Vitis thunbergii, and Ampelopsis brevipedunculaata. The results showed, for the first time, all these plants contain piceatannol. The finding implies that the resveratrol-containing plants may also contain piceatannol. The results demonstrate the feasibility of these sample preparation approaches and may further the understanding for the distribution of piceatannol in plants.

[Study on drug release in vitro and rat intestinal absorption of resveratrol nanoliposomes]

OBJECTIVE

To study the release feature of Res-nanoliposomes in vitro and clarify the difference in absorption of Res-nanoliposomes from varied intestinal segments and the absorptive mechanism in vivo.

METHOD

Dialytic method was used to determine resveratrol release rate of Res-nanoliposomes in vitro. An in situ rat perfusion method was used to investigate the intestinal absorption of Res-nanoliposomes.

RESULT

Resveratrol release from nanoliposomes in vitro fitted the log-normal distribution equation and had a property of sustained release. Compared with other intestinal segments, significantly high percentage of Res-nanoliposomes was absorbed in ileum (P < 0.001). The absorption rate constants (ka) of Res-nanoliposomes in intestine were not significantly different.

CONCLUSION

Res-nanoliposomes could sustain to release drug in vitro. The absorption was a first-order process with the passive diffusion mechanism. The Res-nanoliposomes could promote the absorption of Res in rat small intestine.

Biotransformation of piceid in Polygonum cuspidatum to resveratrol by Aspergillus oryzae

Biotransformation of piceid in Polygonum cuspidatum to resveratrol by Aspergillus oryzae was investigated in this study. Resveratrol is widely used in medicine, food, and cosmetic because of its pharmacological properties. However, it has a much lower content in plants compared with its glucoside piceid, which has a much lower bioavailability. Traditionally, the aglycone is acquired by acid or enzymatic hydrolysis of its glucoside, but the violent condition and the acid pollution in hydrolytic reaction and the high cost of the enzyme limit their industrial development. In this paper, fermentation of P. cuspidatum by A. oryzae was successfully performed, during which, piceid was converted to resveratrol with the highest yield of trans-resveratrol 1.35%, 3.6 times higher than that obtained from raw herb by microwave-assisted extraction. Scale-up production was also performed and the yield of trans-resveratrol was 3.1 times higher after 24 h incubation. Therefore, biotransformation is a better method to increase the yield of resveratrol because of its high yield and mild conditions.

In vitro inhibitory effects of Polygonum cuspidatum on bacterial viability and virulence factors of Streptococcus mutans and Streptococcus sobrinus

OBJECTIVES

Polygonum cuspidatum has been used in Korean folk medicine to improve oral hygiene. This study was performed to evaluate the effects of methanol extract from root of P. cuspidatum (MEP) on bacterial viability and the virulence factors of Streptococcus mutans and Streptococcus sobrinus.

METHODS

To test the effects of MEP on bacterial viability, we determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) against 20 bacterial strains, including S. mutans and S. sobrinus, using a micro-dilution assay. In case of S. mutans and S. sobrinus, the assays for time-kill and bacterial growth rate at sub-MIC concentrations were also performed. To determine effects of the extract on the virulence factors of S. mutans and S. sobrinus, the assays for sucrose-dependent adherence, water-insoluble glucan formation, glycolytic acid production, and acid tolerance were performed at sub-MIC levels. Phytochemical analysis for constituents of MEP was carried out.

RESULTS

MEP showed a broad antibacterial range (MIC 0.5-4 mg/ml). The MBC was two to four times higher than the MIC. The time-kill curves showed S. mutans and S. sobrinus were significantly killed after 1h of incubation. At sub-MIC levels, doubling times of S. mutans and S. sobrinus dose-dependently increased up to 211% and 123%, respectively. At sub-MIC levels, MEP also showed inhibitory effects on the virulence factors of S. mutans and S. sobrinus in a dose-dependent fashion. Phytochemical analysis revealed the presence of alkaloids, sterol/terpenes, tannins, flavonoids, and carbohydrates.

CONCLUSION

These data indicate that MEP has inhibitory effects on bacterial viability at higher concentrations (> or =MIC) and the virulence factors of S. mutans and S. sobrinus at sub-MIC concentrations, suggesting that it might be useful for the control of dental plaque formation and subsequent dental caries formation.

Application of ionic liquids in the microwave-assisted extraction of trans-resveratrol from Rhizma Polygoni Cuspidati

In this paper, the application of 1-n-butyl -3-methylimidazolium-based ionic liquids aqueous solutions as solvents in the microwave-assisted extraction (MAE) technique was first developed for the extraction of trans-resveratrol from Rhizma Polygoni Cuspidati. 1-butyl-3-methylimidazolium bromide ([bmim]Br) solution was selected as solvent; the conditions of MAE including the size of sample, liquid/solid ratio, extraction temperature and time were optimized by means of an orthogonal design L(9)(3(4)). Under optimized conditions, the extraction yield value of trans-resveratrol was 92.8% in a one-step extraction. The recovery was in the range 93.7-103.2% with relative standard deviation lower than 3.0% by the proposed procedure. The method was applied to extract trans-resveratrol from several different region samples. On the basis of extraction solvent and time, the proposed extraction technique was a green, rapid and alternative technique to extract and analyze trans-resveratrol in Rhizma Polygoni Cuspidati samples.

Supercritical CO2 extraction of emodin and physcion from Polygonum cuspidatum and subsequent isolation by semipreparative chromatography

Emodin and physcion are abundant anthraquinone compounds found in the traditional Chinese medicinal herb Polygonum cuspidatum Sied. et Zucc. In this paper, emodin and physcion were successfully extracted with supercritical CO2 plus ethanol modifier after the extraction conditions were optimized with uniform design-sequential optimization. Results showed that the ethanol modifier concentration was the main factor for the effective extraction of the emodin. The optimal extraction condition was obtained: 20 MPa, 30 degrees C, and 95% ethanol, at which the yields of emodin and physcion were 0.616 and 0.178 g/100 g, respectively. The yield obtained by supercritical fluid extraction (SFE) was a little lower than that obtained by sonication extraction (SE). The crude extract obtained by SFE was further isolated and purified by semipreparative chromatography with the mobile phase composed of methanol-water (90:1, v/v). Emodin and physcion were obtained with purity 98.6 and 99.1%, respectively, when determined by HPLC, and identification was performed by retention time and UV spectra of the standards. The result suggested that SFE is an alternative and promising method for extraction of the two compounds from P. cuspidatum owing to its environment-friendly properties and fewer coextracts.

[Studies on active substance of anticancer effect in Polygonum cuspidatum]

OBJECTIVE

To supply the scientific basis of research and development of the medicinal value of Polygonum cuspidatum.

METHODS

One composition was isolated from the roots of Polygonum cuspidatum by cytotoxicity based fractionation and identified by HPLC-MS, UV scanning and IR. The inhibition and morphology of L-02, Hep G2, SHZ-888, MCF-7, MCF-7/ADM cells growth caused by this composition was determined by MTT assay and HE dyeing.

RESULTS

This composition was identified as trans-and cis-resveratrol. It could specifically inhibit proliferation of many cancer cells but not human normal liver cell. We investigated the cytotoxicity of resveratrol to adriamycin-resistant MCF-7 cell in virtro.

CONCLUSION

Resveratrol is a new anticancer composition which is less toxicity and higher efficiency in Polygonum cuspidatum.

[Quantitative determination of the (E) - and (Z) -diastereomers of resveratrol and resveratrol glucoside in the roots of Polygonum cuspidatum by HPLC and elementary study on their fluorescence]

AIM

To establish an optimal HPLC method for the determination of the (E)- and (Z)-diastereomers of resveratrol and resveratrol glucoside from the roots of Polygonum cuspidatum.

METHODS

The determination was conducted by using reversed-phase high liquid chromatography. Nucleodur 100-5 C18 column (250 mm x 4.6 mm ID, 5 microm), and a mobile phase program of gradient elution with isopropyl alcohol and water at a flow rate of 0.6 mL x min(-1) was employed. The fluorescence detection wavelengths were: lambda(ex) 334 nm, lambda(em) 404 nm.

RESULTS

A good linear relationship was obtained under the optimum condition. The average recoveries were 96.7%, 99.1% for the (E)-diastereomers of resveratrol and resveratrol glucoside, 91.1%, 93.7% for the (Z)-diastereomers of resveratrol and resveratrol glucoside, respectively. The RSD of E-resveratrol and its glucoside were 1.34% and 0.72%, respectively. The RSD of Z-resveratrol and its glucoside were 1.27% and 2.08%, respectively.

CONCLUSION

This method is accurate and reliable for the quantity analysis of the (E)- and (Z)-diastereomers of resveratrol and resveratrol glucoside in the roots of Polygonum cuspidatum.

[HPLC fingerprint of Rhizoma Polygoni Cuspidati]

OBJECTIVE

To establish the HPLC fingerprint of Rhizoma Polygoni Cuspidati (Polygonum cuspidatum).

METHOD

The HPLC separation was carried with Diamonsil C18 column and eluted with a gradient from methanol and 0.1% phosphoric acid, the detection wavelength was at 230 nm and recording 70 min. The similarity of chromatograms was compared by mean of the software from Zhongnan University.

RESULT

The constituents of P. cuspidatum were well separated by HPLC, and the similarity was above 0.80.

CONCLUSION

The method can be used for the study of fingerprints of Rhizoma Polygoni Cuspidati.

Analysis of estrogenic compounds in Polygonum cuspidatum by bioassay and high performance liquid chromatography

The estrogenic activity of traditional Chinese herb-Polygonum cuspidatum Sieb. et Zucc. was investigated by a recombinant yeast screening (YES) assay. Anthraquinones are the main components in the plant, of which emodin is the most abundant one. The ethyl acetate fraction of the ethanol extract of Polygonum cuspidatum was separated on a silica gel TLC plate and seven sub-fractions were collected. The results of bioassay demonstrated that Hzs1 and Hzs6 showed higher estrogenic activities than that of others and the potency of these two compounds were approximately 10(-4) g/L and 10(-3) g/L, respectively. HPLC analysis was performed to determine the activities and the active components. Combining the results of HPLC analysis and estrogenic activity test by YES led to the conclusion that an unknown bioactive compound might exist in the extraction of Polygonum cuspidatum.

Leaf epicuticular wax chemicals of the Japanese knotweed Fallopia japonica as oviposition stimulants for Ostrinia latipennis

Extraction, fractionation, and gas chromatography-mass spectrometry analyses guided by bioassays have shown that n-alkanes and free fatty acids in leaf epicuticular wax of the Japanese knotweed Fallopia (Reynoutria) japonica stimulate oviposition in the Far-Eastern knotweed borer, Ostrinia latipennis (Lepidoptera: Crambidae). n-Alkanes made up 48.1% of the total amount of epicuticular wax, and their carbon chain length was in the C(16)-C(33) range, with n-nonacosane (n-C(29)) most abundant, followed by n-C(27), n-C(25), and n-C(31). Free fatty acids with C(9)-C(22) accounted for 22.3%, and hexadecanoic acid was predominant. A mixture of authentic n-alkanes and fatty acids of the composition found in the epicuticular wax, a mixture of n-alkanes, and a mixture of fatty acids significantly enhanced oviposition. Thus, it was demonstrated that both n-alkanes and free fatty acids in leaf epicuticular wax of F. japonica are naturally occurring oviposition stimulants for O. latipennis.

[Contents comparison of resveratrol and polydatin in the wild Polygonum cuspidatum plant and its tissue cultures]

OBJECTIVE

To compare the contents of resveratrol and polydatin in some materials of Polygonum cuspidatum from various sources, so to screen and obtain the suitable cultures for the following metabolism regulation study.

METHOD

RP-HPLC method was applied to simultaneously assay resveratrol and polydatin in different samples.

RESULT

By the modified methods of extraction and determination, large amount of materials were screened. The results indicated that the contents of resveratrol and polydatin in root and rhizome were evidently higher than those in the leave and stems. The content of polydatin in the seedlings cultured indoor for three months was 1.27% and showed a 1.25-time increse than that in the wild plants, while the content of resveratrol (0.401%) approached that in the wild plants. Both of resveratrol and polydatin could be examined from different tissue cultures of P. cuspidatum, such as the sterile seedlings, callus, suspended cells and hairy roots, and the levels of them were closely related to the growth speed, physiological status and developmental phase. Hairy roots had the highest potentiality in several tested cultures and the increase rate of dry weight was 8.29 when cultured in vitro for 30 days, and showed a 8.4-fold and a 192.8-fold increase compared with those of natural roots and suspended cells, respectively. The content of polydatin in the hairy roots was up to 0.037% and that of resveratrol was 0.007%.

CONCLUSION

The established analysis method is rapid, simple and accurate, especially adapted to the simultaneous determination of resveratrol and polydatin in massive biological samples. Hairy-root cultures have the superiority among the tested materials of P. cuspidatum and are suitable for the large-scale biomass and consistent production of efficient constituents.

[Experiment study of tongfu huoxue decoction in the treatment of intracelebral hemorrhage]

OBJECTIVE

To investigate the effects of Tongfu Huoxue decoction on experimental intracelebral hemorrhage and the associated machenisms.

METHOD

The cerebral hemorrhage model in rats was induced by local injection of type VII collagenase and they were randomly divided into four groups. The treated groups were treated with Naoxuekang and Tongfu Huoxue decoction. The control groups were only treated with water. The changes of neurological defect were observed. The content of brain water, MDA, NO and the activity of SOD were measured.

RESULT

The cerebral hemorrhage rats showed hemiplegia, and the hemorrhage brains showed celebral edema, higher quotient of brain and content of brain water, suggesting the hemorrhage model was established successfully. After the treatment of Tongfu Huoxue decoction, the hemorrhage rats showed smaller hemorrhage volume, the brain tissue from the hemorrhage rats had lower MDA content and the quotient of brain, and also had higher activity of SOD and content of NO.

CONCLUSION

Tongfu Huoxue decoction has treatment effects on cerebral hemorrhage.

[Simultaneous determination of resveratrol, emodin, chrysophanol, physcion, in root of Polygonam cuspidatum and its extract by HPLC]

OBJECTIVE

To establish a HPLC method for simultaneous determination of resveratrol, emodin, chrysophanol, physcion in root of Polygonum cuspidatum and its extract.

METHOD

The separation was performed in a Hypersil ODS C18 column with a mobile phase of Acetonitrile-1%HAc. The flow rate was 1.0 mL x min(-1) and detection wavelength was at 287 nm.

RESULT

The mean recovery and RSD of resveratrol, emodin, chrysophanol, physcion was 101.8%, RSD 1.7%; 96.2%, RSD 1.4%; 99.7%, RSD 1.0%; 98.60%, RSD 0.97% respectively.

CONCLUSION

The method is accurate, simple and reliable. It can be used for quality control of P. cuspidatum and its extract.

Differentiation of Rhizoma Et Radix Polygoni Cuspidati from Closely Related Herbs by HPLC Fingerprinting

An HPLC-DAD fingerprinting profile of Rhizoma Et Radix Polygoni Cuspidati was established basing on the consistent chromatographic features of 24 authentic herb samples. The major types of chemical constituents, stilbenes and anthraquinones, were analyzed and included in the fingerprint. Eight common peaks of Polygonum Cuspidatum were identified by using HPLC-MS. The developed fingerprint was applied to differentiate Rhizoma Et Radix Polygoni Cuspidati from Radix Polygoni Multiflori and Radix Et Rhizoma Rhei. Although the three herbs belong to the family of Polygonaceae, the results indicated that these could be differentiated by using the established method.

Preparative isolation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc by high-speed counter-current chromatography

High-speed counter-current chromatography (HSCCC) was applied to the separation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc. The crude extracts from P. cuspidatum Sieb. et Zucc were treated with light petroleum-ethyl acetate-methanol-water (2:5:4:6, v/v). Sample 1 was obtained from the lower phase and sample 2 from the upper phase. The sample 1 was separated with light petroleum-ethyl acetate-water (1:5:5, v/v) and yielded 19.3mg of piceid, 17.6 mg of anthraglycoside B from 200mg of sample 1. The sample 2 was separated with light petroleum-ethyl acetate-methanol-water (3:5:4:6, v/v) and light petroleum-ethyl acetate-methanol-water (3:5:7:3, v/v) in a gradient elution and yielded 18.5mg of resveratrol, 35.3mg of emodin and 8.2mg of physcion from 220 mg of sample 2. The purity of each compound is over 95% as determined by HPLC. The chemical structures of these components were identified by (1)H NMR and (13)C NMR.

[TNF-alpha gene expression of NAFLD rat intervened by the extracts of Rizoma Polygoni Cuspidati]

The real-time qPCR method had been used to detect and analyze the non-alcohol fatty liver disease (NEFLD) model in medical intervention in this research. The relative level of TNF-alpha mRNA in adipose tissue of intervention group was lower than that of control group. Their difference was significant (t = 2.452, P = 0.22). Compared with the control group, it decreased that the contents of liver trilyceride, total cholesterol, and glucose in intervention group. The difference of total cholesterol between two groups was significant (t = 2.555, P = 0.019). The extracts of Rizoma Polygoni Cuspidati could significantly decrease TNF-alpha mRNA level in adipose tissue, and it could decrease the contents of triglyceride, total cholesterol, and glucose in liver tissue. This Chinese traditional medicine can adjust the metabolism of liver adipose and glucose,and improve steatosis in liver cell.

Effects of trans-resveratrol from Polygonum cuspidatum on bone loss using the ovariectomized rat model

trans-Resveratrol (resveratrol) has been shown in several studies to significantly modulate biomarkers of bone metabolism. But, there is no direct evidence supporting its inhibitory effect towards bone loss. In the present study, effects of resveratrol on bone mineral density (BMD) and bone calcium content (BCC) were examined in the ovariectomized (OVX) rat model. Female Wistar rats were divided into four groups: SHAM group (sham-operated), OVX group (OVX control), OVX + ALD group (OVX and treated with 1.0 mg/kg of body weight of alendronate sodium), and OVX + RES group (OVX and treated with 0.7 mg/kg of body weight of resveratrol). Tested materials were given by gavage for 12 weeks after ovariectomy. Results showed that rats in the OVX, OVX + ALD, and OVX + RES groups had significantly higher body weights and feed efficiency than those in the SHAM group (P < .01). The OVX group had significantly lower femoral epiphysis BMD than the SHAM group, and epiphysis BMD in the OVX + ALD and OVX + RES groups was significantly greater than that in the OVX group (P < .05). However, the femoral midpoint BMD was not significantly different among the four groups. Additionally, animals in the OVX group had significantly lower BCC compared with the SHAM group, while the BCC of the OVX + ALD and OVX + RES groups was significantly higher than that of the OVX group (P < .05). These results indicated that resveratrol could increase epiphysis BMD and inhibit the decrease of femur BCC in OVX rats, suggesting that it could play a role in protecting against bone loss induced by estrogen deficiency.

Ethanol extract of Polygonum cuspidatum inhibits hepatitis B virus in a stable HBV-producing cell line

Chronic hepatitis B virus (HBV) infection is endemic in Asia and its consequences are among the major public health problems in the world. Unfortunately, the therapeutic efficacies of present strategies are still unsatisfactory with a major concern about viral mutation. In search of effective antiviral agent, we examined the efficacy of extracts of Polygonum cuspidatum Sieb. et Zucc. (P. cuspidatum) against HBV in HepG2 2.2.15 cells by quantitative real time polymerase chain reaction. The expressions of viral antigens, HBeAg and HBsAg, were also determined by enzyme linked immunosorbent assay. The ethanol extract of P. cuspidatum could inhibit dose-dependently the production of HBV (p<0.0001) with an effective minimal dosage of 10 microg/ml. The water extract of P. cuspidatum might also inhibit the production of HBV at a higher dosage. The expression of HBsAg was significantly increased by both ethanol extract and water extract of P. cuspidatum dose-dependently (p<0.0001) and time-dependently (p<0.0001). Higher dose of water extract of P. cuspidatum (30 microg/ml) could inhibit the expression of HBeAg (p<0.05). The extract of P. cuspidatum might contain compounds that would contribute to the control of HBV infection in the future. However, its promoting effect on the expression of HBsAg and its cytotoxicity should be monitored. Further purification of the active compounds, identification and modification of their structures to improve the efficacy and decrease the cytotoxicity are required.

[Spectral determination of the contents of mineral elements in polygonum cuspidatum]

The present paper reports the determination of mineral elements by FAAS, including K, Ca, Na, Mg, Fe, Zn, Mn and Cu. The best condition for the determination was investigated. The best ionization inhibitor and acidity media were confirmed. The experiment used CsCl to prevent ionization interference, and the concentration of HCl was controlled below 2%. At the same time SrCl prevented interference of P to Ca. So the value of absorbance was stable. The results were obtained by calibration curve method. The analysis method is simple, rapid, accurate and fitting to the determination of mineral elements in plants. The recoveries of the method are 90.5%-108.2%. The relative standard deviations are 0.3%-0.7%. The result show that large amounts of mineral elements are embodied in polygonum cuspidatum. The contents of K and Ca are in conformation with the medical effects of polygonum cuspidatum, and each element is related closely to its growing.

[Effects of meteorological factors and mineral elements on the content of resveratrol in Polygonum cuspidatum rootstalk]

By determining monthly the content of resveratrol and eight mineral elements (Ca, Cu, Fe, K, Mg, Na, Zn, Mn) in the rootstalk of Polygonum cuspidatum, by considering the dynamic meteorological factors and by analyzing the principal components, we are investigating the dynamic relationship laws among mineral elements, meteorological factors and the content of resveratrol in Polygonum cuspidatum rootstalk in varied seasons. The results indicated that the correlation coefficient between Cu and Fe; between Mg and K; between Mg and Zn; between K and Zn; between Ca and average sunlight hours per month are 0.812, 0.871, 0.793, 0.729, 0.602. Their correlation is markedly in the positive 0.01 levels. The correlation coefficient between Cu and average air temperature in a month; between Mn and average air temperature in a month; between Fe and K are -0.738, -0.712, -0.766. Their correlation is markedly in negative 0.01 levels. The correlation between Cu and the content of resveratrol is markedly in negative 0.05 levels. Of the five principal factors affecting the content of resveratrol, two were found to be principal: "mineral element factors of promoting enzyme reacts" and "the meteorological factors of high temperature and strong shines". The percentage results of these two principal are 33.539% and 33.358%, making a total of 68.897%. The two factors above are also the main reasons for the variation of Polygonum cuspidatum resveratrol. A regression equation was set up through correlation and regression analysis between the changing content of resveratrol and the principal component.

Two new bacterial DNA primase inhibitors from the plant Polygonum cuspidatum

The 70% aqueous methanolic extract of the Peruvian plant Polygonum cuspidatum sp. was found to contain two novel phenolic saccharides 1 and 2, which were identified as inhibitors of the bacterial DNA primase enzyme. Structures of these two compounds were established based on high resolution NMR studies. Compound 1 and 2 inhibited the primase enzyme with an IC(50) of 4 and 5 microM, respectively.

[Effect of qianlie huichun capsular on Fas expression and cell apoptosis of prostate gland tissue in rat]

OBJECTIVE

To investigate the effect of Qianlie Huichun capsular on Fas expression and cell apoptosis of prostate gland tissue in the model rat.

METHOD

Hypertrophy of prostate model rat was established by injecting testosterone to gelding male rats. After being treated with Qianlie Huichun ig 30 days, the rats were killed and prostate glands were resected for examination. The Fas expression was examined by immunobistochemical SABC. The cell apoptosis and the peak of cell apoptosis in the prostate gland of the rats were examined by flow cytometry. Compared with model group, the weight of prostage gland tissue in groups treated with Qianlie Huichun capsular was light (P < 0.01).

RESULT

Compared with model group, the Fas expression in all treatment groups increase(P < 0.05, P < 0.01). Compared with normal and model groups, cell apoptosis in all treatment groups increase at different level(P < 0.01).

CONCLUSION

The Qianlie Huchun capsular increases the Fas expression and cell apoptosis of model rats, and shows a definite treatment effect on the hypertrophy of prostate by promoting the apoptosis of prostate cell.

The mechanism of Polydatin in shock treatment

Polydatin is extracted from a traditional Chinese herbal medicine, Polygonum cuspidatum, and has a special effect in shock treatment. The aim of this study is to explain the cellular and molecular basis of Polydatin in shock treatment. The fluorescent probe techniques, patch clamp method, and cellular flow chamber were used to test intracellular variables of vascular smooth muscle cells (VSMC), myocardial cells (MC), endothelial cells (EC), and white blood cell (WBC). It was shown that Polydatin could inhibit ICAM-1 expression in EC stimulated by lipopolysaccharide (LPS), attenuate WBC-EC adhesion, increase [Ca2+]i in MC with enhancement of MC contraction extent, activate KATP channels of VSMC, and decrease pHi value and [Ca2+]i of VSMC in shock. The study suggests that Polydatin has multiple effects on VSMC, MC, WBC and EC, which are related to the enhancement of heart function and improvement of microcirculatory perfusion in shock.