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Vitis thunbergii var. taiwaniana is a vitaceous native folk medicinal plant in Taiwan. The root of V. thunbergii var. taiwaniana is used to treat hepatitis and arthritis. Centrifugal partition chromatography (CPC) and Sephadex LH-20 gel filtration column chromatography were successively used to isolate and purify three oligostilbenes, (−)-vitisin B, (+)-vitisin A, and ampelopsin A, from the root of V. thunbergii var. taiwaniana. The two-phase solvent system of CPC composed of chloroform–methanol–water (6:7:4, v/v/v) was used for the preparative separation of the methanolic extract of V. thunbergii var. taiwaniana. Using CPC and Sephadex LH-20 column chromatography, about 1 g of the crude extract was separated, yielding 28.9 mg of (−)-vitisin B, 18.7 mg of (+)-vitisin A, and 18.2 mg of ampelopsin A at respective purities of 93%, 91%, and 90%.

Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 NAA, 0.2 mg l−1 kinetin and casein hydrolysate 250 mg l−1. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of 500 μM salicylic acid, 100 μM methyl jasmonate, 500 μM ethrel and 500 mg l−1 yeast extract, added on the 7th day, were enhanced by 3- to 6-fold (5–11 mg l−1) by the 15th day.

The cell cultures of Cayratia trifolia (Vitaceae) a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 naphthalene acetic acid, 0.2 mg l−1 kinetin and 250 mg l−1 casein hydrolysate. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin) which on addition of 0.1–0.5 mg l−1 morphactin in the medium containing naphthalene acetic acid and kinetin declined. Morphactin or 2 isopentenyl adenine alone at 0.1 mg l−1 concentration enhanced stilbenes which on combination markedly enhanced the yield to ~5 mg l−1 at 15th day.

It has been reported that resveratrol (trans-3,5,4'-trihydroxystilbene) from Vitis plants has various cardioprotective effects. Vitis plants also include various resveratrol tetramers. The aim of our study is to clarify the pharmacological properties of resveratrol tetramers. We isolated two resveratrol tetramers as major products of Vitis plants. One is vitisin A, a complex of two resveratrol dimers, (+)-epsilon-viniferin and ampelopsin B, and the other is hopeaphenol, composed of 2 mol ampelopsin B. Vitisin A (30-300 nM) unexpectedly dose-dependently facilitated swelling and depolarization of mitochondria and cytochrome c release from mitochondria, which are indices of cardiomyocyte apoptosis. Furthermore, vitisin A induced apoptosis in the primary culture of adult rat ventricular myocytes. On the other hand, hopeaphenol (1-10 microM) dose-dependently inhibited Ca(2+) (30 microM)-induced mitochondrial depolarization and cytochrome c release from mitochondria but had not affected mitochondrial swelling. Moreover, hopeaphenol inhibited vitisin A-induced apoptosis. In structural and functional studies, we further confirmed that vitisin B, one of the resveratrol tetramers having (+)-epsilon-viniferin unit, induces mitochondrial swelling and cytochrome c release from mitochondria like vitisin A and that vitisifuran A, one of the resveratrol tetramers having the ampelopsin B unit, inhibits Ca(2+)-induced cytochrome c release from mitochondria like hopeaphenol. These results show that resveratrol tetramers have at least two opposite effects on cardiomyocytes; the one having the (+)-epsilon-viniferin unit induces cardiomyocyte apoptosis, and the other having ampelopsin B but not (+)-epsilon-viniferin unit inhibits it.

The ecological biochemistry of flavonoids, in which I have been engaged for 25 years, is summarized in this review article. The review covers (1) a survey of rare bio-active flavonoids in higher plants; (2) the fungal metabolism of prenylated flavonoids; (3) flavonoids antidoting against benzimidazole fungicides; (4) dihydroflavonol ampelopsin in Salix sachalinensis as a feeding stimulant towards willow beetles; and (5) flavones as signaling substances in the life-cycle development of the phytopathogenic Peronosporomycete Aphanomyces cochlioides, a cause of spinach root rot and sugar beet damping-off diseases. Finally recent trends in the ecological biochemistry of flavonoids are briefly described.

Ampelopsin (AMP) is an active ingredient of flavonoid compounds that is extracted from Ampelopsis megalophylla Diels et Gilg. The present study aimed at investigating the antitumor activities of AMP and the possible underlying molecular mechanisms in HeLa cells. A total of three types of tumor cell were selected to screen antitumor activities for AMP using the MTT assay. Flow cytometry was used to analyze the cell apoptotic proportion and the cell cycle. Rhodamine 123 staining was used to determine changes in mitochondrial transmembrane potential. Western blot analysis was used to determine the expression of apoptosis-associated proteins. The results of the present study demonstrated that AMP may inhibit the viability of HeLa cells in a dose- and time-dependent manner. Changes in morphology were observed using fluorescence microscopy. In addition, Annexin V-fluorescein isothiocyanate/propidium iodide (PI) double staining revealed that AMP induced apoptosis in a concentration-dependent manner and PI staining indicated that HeLa cells were arrested in S phase. Furthermore, western blot analysis demonstrated that AMP treatment induced apoptosis through activation of caspases 9 and 3, which was validated by the increasing ratio of B-cell lymphoma 2 (Bcl-2)-associated X protein to Bcl-2. Additionally, the loss of mitochondrial transmembrane potential and the release of cytochrome c suggested that AMP-induced apoptosis was associated with the mitochondrial pathway. Taken together, these results indicate that AMP may induce apoptosis via the mitochondrial signaling pathway in HeLa cells.

To improve the solubility and antitumor activity of ampelopsin, ampelopsin-loaded nanomicelles from the mixture of pluronic F127 and D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS1000) were prepared by film-thin hydration method, in order to optimize the process conditions and physicochemical properties. The antitumor activities against MCF-7 cells between ampelopsin and nanomicelles were compared by MTT method, respectively. The results showed that the optimal nanomicelles were round with the nanometric size of (22.6±0.5) nm, encapsulation efficiency rate of (80.42±1.13)%, and drug-loading rate of (4.41±0.26)%. The solubility of ampelopsin in mixed nanomicelles significantly increased by 16 times. In different release media, the mixed nanomicelles could release more than 90% of drug in 8 h, and showed stronger cytotoxicity and inhibition against MCF-7 cells (P

Our results showed that ampelopsin significantly inhibited cell viability of hepatoma HepG2 cells using MTT assay. We further investigated the mechanism of anticancer activity by ampelopsin, it showed that ampelopsin induced apoptosis of HepG2 cells using DAPI assay and flow cytometry, which was confirmed by activation of PARP. Next, activation of the caspase cascades were demonstrated, including caspase-8, -9 and -3. We also found that ampelopsin increased the levels of death receptor 4 (DR4), death receptor 5 (DR5) and decreased the expression of Bcl-2 protein, which led to an increase of the Bax/Bcl-2 ratio. Meanwhile, the release of cytochrome c from mitochondria was observed. Ampelopsin decreased the levels of iNOS and COX-2 but had no impact on the level of reactive oxygen species (ROS). In addition, ampelopsin activated ERK1/2 and P38, but little JNK1/2 activation was detected. Further investigation showed that suppression of P38 activation by SB203580 increased the cell viability and also prevented cleavage of caspase-3 and PARP, inhibition of ERK1/2 with U0126 had the opposite action. In conclusion, our results indicated that ampelopsin mainly elicited apoptosis through extrinsic and intrinsic pathway and that ERK1/2 and P38 had opponent effects on the apoptosis.

A simple, accurate and reproducible reversed-phase liquid chromatographic method was developed for qualitative and quantitative determination of four bioactive flavonoids (ampelopsin, taxifolin, myricetin and quercetin) from the fruit-stalk extract of Hovenia dulcis Thunb. Chromatographic separation was performed on a C18 column (4.6 × 150 mm, 3.5 µm) with mobile phase consisting of 0.1% acetic acid and 100% acetonitrile at a flow rate of 1.0 mL/min. The analysis was performed using a diode array detector at 365 nm. The method was validated in terms of selectivity, linearity, accuracy, precision and recovery. Good linearity was observed over the investigated concentration range (10-500 μg/mL), with correlation coefficient values greater than 0.99. The intra- and inter-day precisions over the concentration range were

Investigating the constituents of the roots of Vitis thunbergii led to the isolation of four new resveratrol derivatives, vitisinols A-D (1-4), together with (+)-epsilon-viniferin, (-)-viniferal, ampelopsin C, miyabenol A, (+)-vitisin A, and (+)-vitisin C. The structures of these 10 compounds were established by spectroscopic (NMR and MS) analyses. All of the isolated compounds, except 1, were tested for their antiplatelet and antioxidative activities.

Salix sachalinensis has two chemotypes: one biosynthesises ampelopsin as a major component of low molecular weight phenolics in their leaves (A-type), and the other biosynthesises b-D-glucopyranose-1-trans-p-coumarate (PG1) and b-D-glucopyranose-1trans-cinnamate (PG2) in addition to ampelopsin (AP-type). We investigated phenotypic and genetic variations and clonal repeatabilities of the pubescence density, leaf mass per area (LMA), and concentrations of total phenolics, condensed tannin, ampelopsin, PG1 and PG2. Leaves of wild A-type trees contained significantly higher concentrations of total phenolics and ampelopsin, and lower concentration of condensed tannin than those of wild AP-type trees. In the greenhouse experiment that compared leaf traits between cloned trees obtained from wild chemotypes, there were significant between-type variations in the leaf phenolic concentrations, pubescence density, and LMA. Since chemotypes of cloned trees in the greenhouse were the same as those of wild parent trees, chemotype can be considered as a genetically controlled property. There were also significant within-chemotype variations in the pubescence density, LMA, total phenolics, ampelopsin, PG1, and PG2 concentrations, but not in concentration of condensed tannin for either chemotypes. Genetic variation of leaf traits except for LMA in AP-type was significant. PG1 and

Hepatoprotective effect of the leaves and stems of Ampelopsis grossedentata together with its main constituent, ampelopsin, were examined on D-galactosamine induced liver injury in rats. The diet containing 50% ethanolic extract (1%) and ampelopsin (0.1%) markedly suppressed the increase of LDH, ALT, AST, alpha-tocopherol levels and GSG/GSSH caused by GalN treatment. These results suggested that ampelopsin from Tocha acted to prevent the oxidative stress in vivo that may have been due to active oxygen species formed by a macrophage by the action of GalN.

Two novel stilbenoids, laevifonol (an e-viniferin-ascorbic acid hybrid compound) and laevifoside (an O-glucoside of ampelopsin A) were isolated from the heartwood of Shorea laeviforia. Their structures were elucidated by nuclear magnetic resonance spectroscopic evidence including HMQC, HMBC, and NOESY. The novel compounds and other known stilbenoids from S. laeviforia were evaluated for inhibitory activity against rat liver 5α-reductase. Positive inhibitory activities were observed in resveratrol dimers and tetramers. No inhibitory activity was detected in laevifonol and ampelopsin A glucosides, laevifoside, or hemsleyanoside, whereas inhibitory activity was seen in their aglycon. These results suggest that the hydrophilic moiety in these compounds may inhibit action with the hydrophobic active site of the enzyme.

Four new stilbene oligomers, gnemonols G, H, I, and J (1–4), were isolated from acetone extract of the root of Gnetum gnemon along with five known stilbenoids, ampelopsin E, cis-ampelopsin E, gnetins C, D, and E. The structures were elucidated on the basis of spectroscopic evidence.

Objectives Erlotinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), has been shown to have a dramatic effect in non-small cell lung cancer (NSCLC) patients with EGFR mutation. However, the presence of primary resistance or acquired resistance to EGFR-TKI is the most common reason for switching to other anti-cancer agents. Even though there are newer agents that have activity in the presence of the T790 M mutation, identification of potential agents that could overcome resistance to EGFR-TKI is still needed for the treatment of NSCLC patients. Materials and methods In this study, we used erlotinib-resistant NSCLC cell lines to investigate the effects of combination treatment with erlotinib and ampelopsin. After treatment with either single or combination, cell viability and cell death were determined with WST-1 assay, trypan blue exclusion method, colony forming assay, annexin-V staining assay and western blot assay. The content of ROS was evaluated by FACS analysis using H2DCF-staining method. To determine the effect of Nox2 and Bim on the combined treatment with erlotinib and ampelopsin-induced cell death, we transfected with Nox2 or Bim specific siRNA and performed with western blot assay for evaluation of its expression. Results Combined treatment with erlotinib and ampelopsin at non-cytotoxic concentrations significantly induced caspase-dependent cell death in erlotinib-resistant NSCLC cells. Furthermore, cell death resulted in the accumulation of reactive oxygen species (ROS) through upregulation of nicotinamide adenine dinucleotide phosphate oxidase 2 (Nox2) expression, a direct source of ROS. The expression level of Bim increased with combination treatment, but not with either treatment alone. Conclusion Here in this study, we demonstrate that the combination of erlotinib and ampelopsin induces cell death via the Nox2-ROS-Bim pathway, and ampelopsin could be used as a novel anti-cancer agent combined with EGFR-TKI to overcome resistance to erlotinib in EGFR-mutant NSCLC.

The aim of this study was to investigate the antioxidant potential of ampelopsin (APS) by using various methods in vitro, as well as to determine effects of APS on LPS-induced oxidative stress in piglets. The results showed that APS exhibited excellent free radical scavenging by DPPH, ABTS, O2•-, H2O2 and ferric reducing antioxidant power. Ampelopsin also protected pig erythrocytes against AAPH-induced apoptosis and hemolysis, decreased total superoxide dismutase activity, and increased lipid peroxidation. Furthermore the results demonstrated that APS enhanced the total antioxidant capacity and decreased the malondialdehyde and protein carbonyl contents in LPS-treated piglets. The results of the present investigation suggest that APS possesses a strong antioxidant activity and alleviates LPS-induced oxidative stress, possibly due to its ability to prevent reactive oxygen species.

Stilbenes have received much attention during the last two decades following the discovery of resveratrol in wine. Since then, there have been a growing number of papers reporting various biological activities of naturally occurring stilbenes. The aim of this study was to determine new minor stilbenes from Vitis vinifera stalks. Purification of these compounds was achieved by means of centrifugal partition chromatography, a versatile separation technique that does not require a solid stationary phase. Viniphenol A (1), a new resveratrol hexamer, was isolated along with five oligostilbenoids identified in V. vinifera for the first time, ampelopsin C, davidiol A, leachianol F, leachianol G, and E-maackin, a dimer with an unusual dioxane moiety, and 14 known hydroxystilbenes. The structure and stereochemistry of viniphenol A were determined on the basis of spectroscopic data analysis and molecular modeling under NMR constraints. Viniphenol A showed protective effects against amyloid-β-induced toxicity in PC12 cell cultures.

A new alkenylphenol, bavinol A (1), together with six known compounds (2–7) were isolated from the aerial parts of Piper bavinum (Piperaceae). The chemical structures of these compounds were determined by spectroscopic analyses including 2D NMR spectroscopy. The anti-Alzheimer effects of compounds 1–7 were evaluated from acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays. Bavinol A (1), ampelopsin (3), and violanthin (4) exhibited AChE inhibitory activities with IC50 values of 29.80, 59.47 and 79.80 μM. Compound 1 also showed the most potent BChE inhibitory activity with an IC50 value of 19.25 μM.

Ampelopsin (AMP), a major bioactive constituent of Ampelopsis grossedentata, exerts a number of biological effects. In this study, we investigated its anti-cancer activity in human breast cancer cell lines, and explored the underlying mechanism of this action. Our results showed that treatment with AMP dose-dependently inhibited cell viability and induced apoptosis in MCF-7 and MDA-MB-231 breast cancer cells without cytotoxicity in human normal breast epithelial cells MCF-10A. Meanwhile, AMP dose- dependently triggered reactive oxygen species (ROS) generation in both breast cancer cells. The ROS scavenger N-acetyl-L-cysteine (NAC) strongly attenuated AMP-induced ROS production, along with cell growth inhibition and apoptosis. Furthermore, AMP was observed to activate endoplasmic reticulum (ER) stress, as evidenced by the up-regulation of ER stress-related proteins, including GRP78, p-PERK, p-elF2α, cleaved ATF6α and CHOP, while knockdown of ATF6α or PERK markedly down-regulated AMP-induced CHOP expression. Blocking ER stress using 4-phenylbutyric acid not only down-regulated AMP-induced GRP78 and CHOP expression, but also significantly decreased AMP-induced cell growth inhibition and apoptosis, whereas ER stress inducer thapsigargin played opposing effects. Additionally, NAC inhibited AMP-induced ER stress by down-regulating GRP78 and CHOP expression. Conversely, blocking ER stress using CHOP siRNA decreased AMP-induced ROS production and cell apoptosis. Taken together, these results demonstrate that AMP has anti-tumor effects against breast cancer cells through ROS generation and ER stress pathway, which therefore provide experimental evidences for developing AMP as a new therapeutic drug for breast cancer.

Five resveratrol tetramers, amurensins I–M, were isolated from the roots of Vitis amurensis (Rupr.), together with five known resveratrol tetramers, (+)-hopeaphenol, isohopeaphenol, vitisin A, (+)-vitisifuran A, and heyneanol A. Their structures and stereochemistry were determined by chemical and spectroscopic methods, especially by use of 2D NMR analysis. Some of them had an ampelopsin A or a balanocarpol unit, in which the conformations of the seven-membered carbon ring were described for the first time. The anti-inflammatory activities of the tetramers were also tested. Among them, (+)-hopeaphenol, isohopeaphenol, vitisin A, (+)-vitisifuran A and heyneanol A showed potent inhibition on the biosynthesis of leukotriene B 4 (LTB 4 ), and amurensins I and L showed strong antagonism of the histamine acceptor.

5α-Reductase inhibitory activity of methanol extracts of the heartwood of 13 tropical wood species were examined. Strong 5α-reductase inhibitory activity was observed withShorea species. From melapi (Shorea sp.), two known resveratrol trimers, vaticanol A and ampelopsin C, and two novel trimers were isolated as active compounds. The structures of the two novel resveratrol trimers were elucidated by one- and two-dimensional nuclear magnetic resonance spectroscopic analyses, including1H-1HCOSY, HMQC, and HMBC. The compounds were named melapinol A and melapinol B. There were no significant differences among the 5α-reductase inhibitory activities of the four resveratrol trimers, which were significantly stronger than those ofα-linolenic acid and epigallocatechin gallate, known 5α-reductase inhibitors.

To measure the antifungal potency of plant secondary metabolites, we did an antifungal test using Cladosporium herbarum as a test fungus and minute extracts of some plants. This test showed that the methanol extract of Salix sachalinensis leaves had strong antifungal activity. An antifugal principle in the leaves has been identified as (2R, 3R)-(+)-5,7,3',4',5'-pentahydroxy-dihydroflavonol (ampelopsin). The antifungal potency of S.sachalinensis leaves was not due to an antifungal constituent with high specific activity, but due to the high content of ampelopsin. To improve the antifungal activity, ampelopsin was made into variously methylated derivatives,and these products were bioassayed. 7,3',4'-Tri-omicron-methylampelopsin,out of 8 derivatives, had the strongest antifungal activity, which was about 4 times that of ampelopsin. The structure-activity relationship is briefly discussed.

A dimer resveratrol compound named (-)-ampelopsin A was isolated from acetone extract of the stem bark of Dryobalanops oblongifolia (Dipterocarpaceae). The structure of this compound was determined on the basis of NMR spectroscopic data. Keywords: (-)-ampelopsin A, Dryobalanops oblongifolia, Dipterocarpaceae

Ampelopsin (AMP), a plant flavonoid, has been reported to inhibit cell growth and/or induce apoptosis in various types of tumor. The aim of the present study was to assess the apoptosis-inducing activity of AMP in A549 human lung adenocarcinoma epithelial cells and the associated underlying mechanism. A549 cells were incubated with different concentrations of AMP in culture medium. Cell growth and apoptosis were evaluated by MTT assay and Annexin V/propidium iodide double staining and flow cytometry, respectively. In addition, western blotting and reverse transcription quantitative polymerase chain reaction analysis were used to examine the time-dependent changes in protein expression. Certain changes in apoptotic protein expression were detected following exposure to AMP, including X-linked inhibitor of apoptosis protein release, reduced B-cell lymphoma 2, myeloid cell leukemia 1 and survivin expression levels, increased Bcl-2-associated X protein expression levels and cleaved-poly ADP ribose polymerase expression. The results revealed that AMP was a potent inhibitor of A549 cell proliferation. The c-Myc/S-phase kinase-associated protein 2 (Skp2) and histone deacetylase (HDAC)1/2 pathways were found to exert an important role in AMP-induced A549 cell apoptosis, as increased levels of c-Myc mRNA and reduced levels of c-Myc/Skp2 and HDAC1 and 2 proteins following AMP treatment were observed. The levels of F-box and WD repeat-containing protein 7α (Fbw7α), Fbw7β, Fbw7γ, phosphorylated-(p−)c-Myc (Thr58) and glycogen synthase kinase 3β (GSK3β) proteins involved in c-Myc ubiquitin-dependent degradation were also analyzed. Following exposure to AMP, the expression levels of Fbw7α, Fbw7γ and GSK3β were reduced and p-c-Myc (Thr58) expression levels were increased. The results suggest that AMP exerts an anticancer effect, which is associated with the degradation of c-Myc, Skp2 and HDAC1 and 2. The ability of AMP to induce apoptosis independently of Fbwα and Fbw7γ suggests a possible use in drug-resistant cancer associated with Fbw7 deficiency. Understanding the exact underlying mechanism requires further investigation of the association between c-Myc and Fbw7α/γ reversal, and analysis of whether Thr58 phosphorylation of c-Myc is dependent on GSK3β.

Three sulfated phenolic compounds, juglanin B (11 R )- O -sulfate ( 1 ), myricetin 3´- O -sulfate ( 2 ), and ampelopsin 3´- O -sulfate ( 3 ), were isolated from the leaves of Myrica rubra. Compound 1 was a new sulfated lignan, 2 was a new sulfated flavone, and 3 was a known sulfated flavone. The structures of the new compounds ( 1 and 2 ) were determined by acid hydrolysis and spectroscopic methods, including IR, FAB-MS, 1D and 2D NMR. The inhibitory activities of compounds 1 – 3 and their hydrolysates ( 1a – 3a ) against LPS-induced cytokine (TNF-α, IL-1β, and IL-6) production in macrophage RAW 264.7 cells were evaluated. The 2 new compounds ( 1 and 2 ) and their aglycones ( 1a and 2a ) significantly reduced LPS-induced expression of iNOS and COX-2 proteins.

Methanolic and ethanolic crude extracts of Vitis vinifera canes exhibited significant antifungal activity against the three major fungal pathogens affecting grapevines, Plasmopara viticola, Erysiphe necator and Botrytis cinerea. The active extracts were analyzed by LC-PDA–ESI-MS, and selected compounds were identified. Efficient targeted isolation using medium-pressure liquid chromatography afforded six pure constituents in one step. The structures of the isolated compounds were elucidated by NMR and HRMS. Six identified compounds (ampelopsin A, hopeaphenol, trans-resveratrol, ampelopsin H, e-viniferin, and E-vitisin B) presented antifungal activities against P. viticola. e-Viniferin also exhibited a low antifungal activity against B. cinerea. None of the identified compounds inhibited the germination of E. necator. The potential to develop a novel natural fungicide against the three major fungal pathogens affecting V. vinifera from viticulture waste material is discussed.

Vitis thunbergiiis used in Taiwan as a botanical supplement for inflammatory bone diseases. This study aims to examine its direct effect on bone metabolism. Three-month-old female mice were randomly divided into ovariectomized control (OVX), sham operated (SHAM), and ovariectomy treated with either 17β-estradiol or a special ingredient (VtR) fractionated from an ethanol extract ofV. thunbergiistarted two weeks after ovariectomy. VtR treatment for 8 weeks significantly ameliorated the deterioration of bone mineral density and reversed all the ovariectomy-induced changes in μ-CT parameters. The antiosteoporotic effect of VtR accompanied decrease in serum levels of C-terminal telopeptides of type I collagen (CTx), interleukin-7, and ration of RANKL/osteoprotegerin (OPG) but rise in osteocalcin concentration. Sparse calcified microarchitecture and less alkaline-phosphatase- (ALP-) positive cells were observed at the femur and vertebral sites in OVX mice while VtR remarkably restored such variation. HPLC analysis showed (+)-vitisin-A, (−)-vitisin-B, and ampelopsin C predominated in VtR. Both (−)-vitisin B and ampelopsin C increased ALP activity and bone nodule formation in cultured osteoblasts. Instead of stimulating osteoblastogenesis, (+)-vitisin A dramatically repressed osteoclasts differentiation and bone resorption. The results suggested VtR composed of diverse components to reciprocally drive osteoblastogenesis and interdict osteoclastogenesis may serve as a potential botanic drug for osteoporosis therapy.

Ampelopsin (APL), a major bioactive constituent of Ampelopsis grossedentata, exerts a number of biological effects. Here, we explored the anti-diabetic activity of APL and elucidate the underlying mechanism of this action. In palmitate-induced insulin resistance of L6 myotubes, APL treatment markedly up- regulated phosphorylated insulin receptor substrate-1 and protein kinase B, along with a corresponding increase of glucose uptake capacity. APL treatment also increased expressions of fibroblast growth factor (FGF21) and phosphorylated adenosine 5'-monophosphate -activated protein kinase (p-AMPK), however inhibiting AMPK by Compound C or AMPK siRNA, or blockage of FGF21 by FGF21 siRNA, obviously weakened APL -induced increases of FGF21 and p-AMPK as well as glucose uptake capacity in palmitate -pretreated L6 myotubes. Furthermore, APL could activate PPAR γ resulting in increases of glucose uptake capacity and expressions of FGF21 and p-AMPK in palmitate -pretreated L6 myotubes, whereas all those effects were obviously abolished by addition of GW9662, a specific inhibitor of peroxisome proliferator- activated receptor -γ (PPARγ), and PPARγsiRNA. Using molecular modeling and the luciferase reporter assays, we observed that APL could dock with the catalytic domain of PPARγ and dose-dependently up-regulate PPARγ activity. In summary, APL maybe a potential agonist of PPARγ and promotes insulin sensitization by activating PPARγ and subsequently regulating FGF21- AMPK signaling pathway. These results provide new insights into the protective health effects of APL, especially for the treatment of Type 2 diabetes mellitus.

The aim of this study is to determine the combined effects of stilbenoids from Shorea gibbosa and vancomycin against methicillin-resistant Staphylococcus aureus (MRSA). A total of nine pure compounds, five stilbenoid dimers ε-viniferin, ampelopsin A, balanocarpol, laevifonol and diptoindonesin G and four stilbenoid trimers a-viniferin, johorenol A, ampelopsin E and vaticanol G were evaluated for their antibacterial activities against ATCC 33591 and a HUKM clinical isolate. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for each active compound were determined using the serial microdilution and plate-streak techniques. The combined effect of stilbenoids with vancomycin against MRSA was evaluated using the checkerboard assay to determine their fractional inhibitory concentration (FIC) index values. The MIC value of a-viniferin on both MRSA strains was 100 μg/mL, whereas those of johorenol A on ATCC 33591 and HUKM strain were 100 μg/mL and 200 μg/mL, respectively. The MIC values of ampelopsin E and vaticanol G were higher than 400 μg/mL. Out of the five stilbenoid dimers, only ε-viniferin was capable of inhibiting the growth of both MRSA strains at MIC 400 μg/mL. The MBC value of ε-viniferin, a-viniferin and johorenol A showed bacteriostatic action against MRSA. The FIC index value of ε-viniferin and a-viniferin in combination with vancomycin showed an additive effect (0.5 < FIC ≤ 2.0) against both MRSA strains. Johorenol A-vancomycin combination was also additive against HUKM strain, but it showed synergistic interaction with vancomycin against ATCC 33591 (FIC < 0.5). Stilbenoid compounds from Shorea gibbosa have anti-MRSA activity and huge potential as an alternative phytotherapy in combating MRSA infections.

Here, proof-of-concept of a new analytical platform used for the comprehensive analysis of a small set of commercial willow bark products is presented, and compared with a traditional standardization solely based on analysis of salicin and salicin derivatives. The platform combines principal component analysis (PCA) of two chemical fingerprints, i.e., HPLC and (1)H NMR data, and a pharmacological fingerprint, i.e., high-resolution 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS(+)) reduction profile, with targeted identification of constituents of interest by hyphenated HPLC-solid-phase extraction-tube transfer NMR, i.e., HPLC-SPE-ttNMR. Score plots from PCA of HPLC and (1)H NMR fingerprints showed the same distinct grouping of preparations formulated as capsules of Salix alba bark and separation of S. alba cortex. Loading plots revealed this to be due to high amount of salicin in capsules and ampelopsin, taxifolin, 7-O-methyltaxifolin-3'-O-glucoside, and 7-O-methyltaxifolin in S. alba cortex, respectively. PCA of high-resolution radical scavenging profiles revealed clear separation of preparations along principal component 1 due to the major radical scavengers (+)-catechin and ampelopsin. The new analytical platform allowed identification of 16 compounds in commercial willow bark extracts, and identification of ampelopsin, taxifolin, 7-O-methyltaxifolin-3'-O-glucoside, and 7-O-methyltaxifolin in S. alba bark extract is reported for the first time. The detection of the novel compound, ethyl 1-hydroxy-6-oxocyclohex-2-enecarboxylate, is also described.

Novel ampelopsin glucosides (AMPLS-Gs) were enzymatically synthesized and purified using a Sephadex LH-20 column. Each structure of the purified AMPLS-Gs was determined by nuclear magnetic resonance, and the ionic product of AMPLS-G1 was observed at m/z 505 (C₂₁H₂₂O₁₃·Na)⁺ using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. AMPLS-G1 was identified as ampelopsin-4'-O-α-D-glucopyranoside. The optimum condition for AMPLS-G1, determined using response surface methodology, was 70 mM ampelopsin, 150 mM sucrose, and 1 U/mL dextransucrase, which resulted in an AMPLS-G1 yield of 34 g/L. The purified AMPLS-G1 displayed 89-fold increased water solubility and 14.5-fold browning resistance compared to those of AMPLS and competitive inhibition against tyrosinase with a K(i) value of 40.16 μM. This value was smaller than that of AMPLS (K(i)=62.56 μM) and much smaller than that of β-arbutin (K(i)=514.84 μM), a commercial active ingredient of whitening cosmetics. These results indicate the potential of AMPLS and AMPLS-G1 as superior ingredients for functional cosmetics.

The objective of this study was to evaluate the chemopreventive effect of a novel flavonoid, ampelopsin (AMP) on the growth and metastasis of prostate cancer cells. AMP showed the more potent activity in inhibiting the proliferation of androgen-sensitive LNCaP and, to less extent, androgen-independent PC-3 human prostate cancer cell lines in vitro, primarily by induction of apoptosis associated with down-regulation of bcl-2. On the other hand, AMP showed much less activity in inhibiting the proliferation of normal prostate epithelial cells than that of prostate cancer cell lines. AMP also inhibited the migration and invasion of PC-3 cells in vitro associated with down-regulation of CXCR4 expression. In the animal study using an orthotopic prostate tumor model, AMP (150 and 300 mg/kg body weight) inhibited the growth of PC-3 tumors and lymph node and lung metastases in a dose-dependent manner. Compared to the control mice, mice treated with AMP at 300 mg/kg BW had reduced final tumor weight by 49.2% (P

Ampelopsin, one of the most common flavonoids, reported to possess numerous pharmacological activities and shows poor aqueous solubility. The purpose of this study was to enhance the dissolution rate and bioavailability of this drug by developing a novel delivery system that is microemulsion (ME) and to study the effect of microemulsion (ME) on the oral bioavailability of ampelopsin. Capmul MCM-based ME formulation with Cremophor EL as surfactant and Transcutol as cosurfactant was developed for oral delivery of ampelopsin. Optimised ME was evaluated for its transparency, viscosity, percentage assay and so forth. Solubilisation capacity of the ME system was also determined. The prepared ME was compared with the pure drug solution and commercially available tablet for in vitro drug release. The optimised ME formulation containing ampelopsin, Capmul MCM (5.5%), Cremophor EL (25%), Transcutol P (8.5%), and distilled water showed higher in vitro drug release, as compared to plain drug suspension and the suspension of commercially available tablet. These results demonstrate the potential use of ME for improving the bioavailability of poor water soluble compounds, such as ampelopsin.

The interaction between bovine serum albumin (BSA) and the anticancer drug molecule ampelopsin (AMP) was investigated using fluorescence spectroscopy, circular dichroism (CD) spectra, and time-resolved spectra under simulated physiological conditions. Fluorescence data showed that the intrinsic fluorescence of BSA was strongly quenched by AMP in terms of a dynamic quenching process. Binding constants and binding sites were calculated. The thermodynamic parameters indicated that the hydrogen bonding and weak van der Waals force played a major role in the interaction. The site marker competitive experiments suggested that the binding site of AMP and BSA was probably located on site III. Based on the Forster's theory, the average binding distance between AMP and BSA was obtained (r = 5.47 nm). The binding of AMP and BSA leaded to conformational changes of BSA according to synchronous fluorescence spectra, CD data and mean fluorescence lifetime values.

Ampelopsin (AMP), a plant flavonoid, has potent anti-inflammatory properties in vitro and in vivo. The molecular mechanisms of ampelopsin on pharmacological and biochemical actions of RAW264.7 macrophages in inflammation have not been clearly elucidated yet. In the present study, non-cytotoxic level of ampelopsin significantly inhibited the release of nitric oxide (NO) and pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α in a dose-dependent manner. Consistent with NO inhibition, ampelopsin suppressed lipopolysaccharide (LPS)-induced expression of inducible NO synthase (iNOS) by inhibiting nuclear factor κB (NF-κB) activation, which highly correlated with its inhibitory effect on IκB kinase (IKK) phosphorylation, IκB phosphorylation and NF-κB nuclear translocation. Further study demonstrated that ampelopsin suppressed LPS-induced activation of Akt without effecting mitogen-activated protein kinases (MAPKs) phosphorylation. A pharmacological inhibitor of the phosphoinositide 3-kinase (PI3K)-Akt pathway, LY294002, abrogated IKK/IκB/NF-κB-mediated iNOS gene expression. Finally, we certificated that ampelopsin reduced reactive oxygen species (ROS) accumulation and an anti-oxidant N-acetyl-L-cysteine (NAC) significantly repressed LPS-induced PI3K/Akt phosphorylation and the downstream IKK/IκB activation. NAC thereby inhibited LPS-induced iNOS expression and NO production. The present results suggest that the anti-inflammatory effect of ampelopsin is due to inhibiting the interconnected ROS/Akt/IKK/NF-κB signaling pathways.

Vitis thunbergii Sieb. and Zucc. var. taiwaniana Lu is an endemic plant in Taiwan used as a dietary supplement for bone health. In this study, human chondrocytes were induced to produce COX-2, MMP-3, -13, and PGE(2) by LPS. An (18)F-FDG microPET imaging system was used to evaluate the anti-inflammatory arthritic effects in vivo. Six stilbenes, resveratrol (1), (+)-epsilon-viniferin (2), ampelopsin C (3), ampelopsin A (4), (-)-vitisin B (5), and ()-vitisin A (6), were isolated from the stem part of V. thunbergii, which displayed the strongest PGE2 inhibition. Among these compounds, 1 significantly decreased COX-2 activity, PGE(2), MMP-3, and -13 production in vitro, and (18)F-FDG uptake and serum PGE(2) in rabbits in vivo. Anti-inflammatory effects were enhanced through the combined usage of 1 and other oligostilbenes. Taken together, the synergistic effects of 1 and oligostilbenes resulted in stem part extracts with lower 1 content displaying the better anti-inflammatory arthritis effects.

The methanol extract of the roots of Ampelopsis brevipedunculata var. hancei exhibited marked protective activity against carbon tetrachloride and d -galactosamine-induced liver damage in primary cultured rat hepatocytes. The extract was fractionated by monitoring the activity to give active fractions from which four novel oxidative oligostilbenes, ampelopsins D, E, H and cis-ampelopsin E, were isolated in addition to the known compounds, (-)-epicatechin, pallidol, miyabenol C, piceid, cis-piceid and resveratroloside. The structures of the new stilbene derivatives have been established on the basis of spectroscopic evidence and chemical reactions. Among them, ampelopsin E and cis-ampelopsin E showed antihepatotoxic activity.

A new resveratrol trimer, malaysianol A (1), five known resveratrol oligomers: laevifonol (2), ampelopsin E (3), α-viniferin (4), e-viniferin (5), diptoindonesin A (6), and bergenin (7) have been isolated from the acetone extract of the stem bark of Dryobalanops aromatica by combination of vacuum and radial chromatography techniques. Their structures were established on the basis of their spectroscopic evidence and comparison with the published data. The cytotoxic activity of the compounds was tested against several cell lines in which compound 4 was found to inhibit strongly the growth of HL-60 cell line.

In Pinus sylvestris there are two chemotypes—those with (2R, 3R)‐trans‐taxifolin 3´‐O‐s‐D‐glucopyranoside ( = T) and those without this substance. Trees containing T also contained the biochemically related 3´‐O‐s‐D‐glucopyranoside of eriodictyol and ampelopsin (E and A, respectively). Analyses of E, T and A were performed with HPLC and/or TLC. A rapid extraction with aqueous ethanol followed by TLC was used for identification of T. The segregation in T‐rich and T‐free trees was determined in twenty‐nine progenies from crosses or selfings in Pinus sylvestris. Except for six selfed trees which were assumed to be due to illegitimate fertilization, all data supported a monohybrid inheritance of the presence of T in P. sylvestris needles, with T‐free trees being recessive homozygotes. The concentration of E, T and A in trees containing these flavonoids is modified by other genes. The analyses of 240 trees for A and E are consistent with a monohybrid inheritance.

Human immunodeficiency virus (HIV) infection can result in oxidative stress through production of reactive oxygen species (ROS). Simultaneously, oxidative stress is able to activate the replication of virus and lead to the apoptosis of T lymphocytes which is the defense of the immune function. Ampelopsin, belonging to the flavonoids, is a purified component from the root of a Chinese medicinal herb. Our previous studies revealed that ampelopsin could protect sensitive cells against HIV-1 infection and reduce HIV-1 antigen P24 expression. In this study, we determined whether ampelopsin, as an antioxidant, has protective effects on oxidant stress-induced apoptosis in MT-4 cells, a CD 4 T lymphocyte cell line. The results indicate that ampelopsin scavenged hydroxyl radicals ( ·OH) and superoxide radicals (O 2 .-) in a concentration-dependent manner. It significantly increased MT-4 cells viability after treatment with H 2 O 2 and inhibited H 2 O 2 -induced DNA laddering. The data from flow cytometry analysis showed that ampelopsin remarkably decreased the percentage of apoptotic cells induced by H 2 O 2 . In addition, activation of caspase-3 was detected during the course of apoptosis induction. Western blot analysis showed that ampelopsin inhibited the cleavage of caspase-3 induced by H 2 O 2 . All these findings might shed new light on the understanding of the anti-AIDS functions of ampelopsin by protecting T cells of persons infected with HIV.

A new oligostilbenoid derivative, diptoindonesin F (1), along with five known oligostilbenoids, (-)-ampelopsin A (2), (-)-alpha-viniferin (3), ampelopsin E (4), (-)-vaticanol B (5), and (-)-hemsleyanol D (6), were isolated from the methanol extract of the tree bark of Shorea gibbosa. The structure of the new compound was determined based on the analysis of spectroscopic data, including UV, IR, NMR 1-D and 2-D, and mass spectra. Cytotoxic properties of the isolated oligostilbenoids were evaluated against murine leukemia P-388 cells with the result that compounds 2 and 4 showed the highest cytotoxicity.

From the stem wood of Parthenocissus tricuspidata, four stilbene derivatives were isolated. Three known structures were characterized as resveratrol, e-viniferin and pallidol, and a new resveratrol dimer was confirmed to be a stereochemical isomer of ampelopsin F, isoampelopsin F, by spectroscopic analysis including 2D NMR.