Steroid glycosides isolated from Paris polyphylla var. chinensis aerial parts and paris saponin II induces G1/S-phase MCF-7 cell cycle arrest.

In our previous research on Vietnamese medicinal plants, we found that the ethanolic extract of the aerial parts of Paris polyphylla var. chinensis exhibited cytotoxic effects in vitro in the MCF-7 human cancer cell line. Here, we used combined chromatographic separations to isolate six compounds including a new steroid glycoside, paripoloside A (3), and five known compounds, from the butanol extract of the aerial parts of P. polyphylla. We unambiguously elucidated their structures based on spectroscopic data (proton and carbon-13 nuclear magnetic resonance, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, correlation spectroscopy, and high-resolution electrospray ionization mass spectroscopy data), and chemical reactions. Among the isolated compounds, paris saponin II (PSII) had the strongest cytotoxic effects against MCF-7 breast cancer cells. Interestingly, PSII significantly increased the expression of p53, p21, p27, and Bax protein levels and significantly suppressed the expression of cyclin D1 and retinoblastoma protein. These data suggest that PSII may induce G1/S phase cell cycle arrest and apoptosis pathway development in MCF-7 cells. Furthermore, the MCF-7 breast cancer cells mechanism of PSII was also investigated using molecular docking. Together, our results demonstrate that isolated compounds from P. polyphylla are promising candidates as breast cancer inhibitors.

Four New Compounds Isolated from the Aerial Part of Belamcanda chinensis (L.) and Their Effect on Vascular Smooth Muscle Cell (VSMC) Proliferation.

Bio-guided fractionation of the 70% ethanol extract of Belamcanda chinensis (L.) DC. revealed four new compounds, including 6″-O-acetylembinin (5), 3″-O-acetylembinin (6), irigenin 3'-O-ß-glucopyranoside (8), and 2'-acetyl-1,3-O-diferuloylsucrose (9), along with five known compounds (1-4, 7). Their chemical structures were determined using extensive NMR data, mass spectroscopy, and comparison with published literature. Among the isolates, compounds 1 and 4-7 achieved good regulation of the growth and proliferation of vascular smooth muscle cells.

Anti-inflammatory effect of oligostilbenoids from Vitis heyneana in LPS-stimulated RAW 264.7 macrophages via suppressing the NF-κB activation.

BACKGROUND: Vitis heyneana is widely distributed in the north of Vietnam, it has been used in Vietnamese traditional medicine as an agent for treatment of arthritis, bronchitis, carbuncles and inflammatory conditions, and menstrual irregularities. However, this plant has not been investigated in phytochemical constituents and biological effects, especially in the anti-inflammatory property. RESULTS: Bioassay-guided fractionation of the EtOAc soluble fraction from the aerial part of Vitis heyneana resulted in the isolation of a series of oligostilbenoids as piceid (1), 2-r-viniferin (2), betulifol A (3), vitisinol C (4), (-)-trans-ε-viniferin (5), α-viniferin (6), shoreaketon (7), amurensin B (8), vitisinol B (9), and cis-vitisin B (10). Compound 5 showed the most potent inhibitory activities by suppressing LPS-induced COX-2 expression and PGE2 production. This compound exhibited significantly reduced LPS-induced nitric oxide (NO) release in a dose-dependent manner. These effects are accompanied with the inhibition of transcription factor NF-κB activation. CONCLUSION: The results suggested that trans-ε-viniferin exerts anti-inflammatory effects via suppression the NF-κB activation in RAW 264.7 cells.

Palbinone from Paeonia suffruticosa protects hepatic cells via up-regulation of heme oxygenase-1.

Paeonia suffruticosa has been traditionally employed for vitalizing blood circulation and alleviating liver and inflammatory diseases. The pathways by which palbinone (PB) isolated from P. suffruticosa mediates heme oxygenase-1 (HO-1) induction were investigated using the specific inhibitors for PI3K and mitogen activated protein kinases pathways. The effect of PB-treatment on Nrf2 translocalization and HO-1-antioxidant response element (ARE) regulation was examined employing Western blot and luciferase assays. PB induced HO-1 expression via the activation of Nrf2 in the hepatic cells, and ARE-dependent genes were stimulated via the PB-mediated Nrf2 activation. PB-mediated HO-1 expression could be involved with PI3K/Akt and ERK1/2 pathways. Our study suggests the mechanism by which PB induces HO-1 expression in the hepatic cells. This might substantiate the traditional applications of P. suffruticosa for the treatment of oxidative stress-related diseases including oxidant and inflammatory-mediated vascular and liver diseases.

In vitro and in vivo hepatoprotective effect of ganodermanontriol against t-BHP-induced oxidative stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Ganoderma lucidum (Fr.) Karst. (Ganodermataceae) is a mushroom which is used as a traditional remedy in the treatment of human diseases such as hepatitis, liver disorders, hypercholesterolemia, arthritis, bronchitis and tumorigenic diseases. This study targets the evaluation of hepatoprotective activity of ganodermanontriol, a sterol isolated from Ganoderma lucidum, and the investigation of its mechanism of action in Hepa1c1c7 and murine liver cells upon tert-butyl hydroperoxide (t-BHP)-induced inflammation. t-BHP was utilized to stimulate an anti-inflammatory reaction in the hepatic cell lines and murine hepatic tissue examined. Western blot and reverse transcription-quantitative polymerase chain reaction (RT-PCR) were used to estimate the expression of ganodermanontriol (GDT)-induced proteins, including heme oxidase-1 (HO-1) and mitogen-activated protein kinases (MAPKs) as well as the corresponding mRNA. Luciferase assays were conducted to evaluate the interaction between NF-E2-related factor-2 (Nrf-2), the antioxidant response element (ARE), and the promoter region of the HO-1 gene and subsequent gene expression. Biochemical markers for hepatotoxicity were monitored to assess whether GDT protected the cells from the t-BHP-mediated oxidative stimuli. RESULTS: GDT induced HO-1 expression via the activation of Nrf-2 nuclear translocation and the subsequent transcription of the HO-1 gene in vitro and in vivo, which seemed to be regulated by phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and p38 signaling pathways. GDT exhibited in vitro and in vivo hepatoprotective activity as determined by the lowered levels of hepatic enzymes and malondialdehydes and the elevated glutathione levels. CONCLUSIONS: This study validates the ethnopharmacological application of Ganoderma lucidum as a treatment for hepatic disorders. GDT induced in vitro and in vivo anti-inflammatory activity in t-BHP-damaged hepatic cells through the expression of HO-1, and in which PI3K/Akt and p38 kinases are involved. Our study motivates further research in the exploration of potent hepatoprotective agents from Ganoderma lucidum.

Constituents from the stem barks of Canarium bengalense with cytoprotective activity against hydrogen peroxide-induced hepatotoxicity.

Phytochemical investigation of the stem barks of Canarium bengalense (Burseraceace) resulted in the isolation of a new flavone glycoside (5) together with six known compounds (1-4, 6, and 7). The chemical structure of the new compound was elucidated as 3'-hydroxy-7,4'-dimethoxyflavone-5-O-α-L-arabinofuranosyl-(1→6)-ß-D-glucopyranoside by means of 1D and 2D NMR ((1)H-(1)H COSY, HMQC, and HMBC) and MS analyses. To evaluate the in vitro cytoprotective effect, the isolates (1-7) were tested against hydrogen peroxide (H(2)O(2))-induced damage in primary cultured hepatocytes. The viability of hepatocytes was increased by treatment with each compound, except compound 1. Compounds 3, 4, and 7 exerted cytoprotective effects comparable to curcumin, the positive control. Our results suggest that the cytoprotective constituents of C. bengalense may contribute to its traditional use in the treatment of tumor and liver damage.

Adlay seed extract (Coix lachryma-jobi L.) decreased adipocyte differentiation and increased glucose uptake in 3T3-L1 cells.

The aim of the present study was to investigate effects of the ethyl acetate fraction of an ethanol extract of Coix lachryma-jobi (ECLJ) on glucose uptake and adipocyte differentiation in 3T3-L1 cells. ECLJ phosphorylated AMP-activated protein kinase (AMPK) and its downstream substrate acetyl-coenzymeA carboxylase in 3T3-L1 cells in a time- and dose-dependent manner. Moreover, we discovered that compound C inhibits ECLJ-stimulated ACC phosphorylation. In addition, ECLJ exhibited a dose-dependent stimulation of glucose uptake in 3T3-L1 cells, and this increase was obviously attenuated by compound C. ECLJ also caused a decrease in the expression levels of adipogenesis factors such as fatty acid synthase, sterol-regulatory-element-binding protein-1c, peroxisome proliferator-activated receptor γ, and CAATT/enhancer binding protein α in a dose-dependent manner. Differentiation was examined by Oil red O staining activity after ECLJ treatment for 6 days. ECLJ decreased mean droplet size. These results suggest a possible role for AMPK in the process of adipose differentiation and that ECLJ targeted for adipocyte functions could be effective in improving the symptoms of metabolic syndrome.

Leaf and stem of Vitis amurensis and its active components protect against amyloid ß protein (25-35)-induced neurotoxicity.

This study investigated a methanol extract from the leaf and stem of Vitis amurensis (Vitaceae) for possible neuroprotective effects on neurotoxicity induced by amyloid ß protein (Aß) (25-35) in cultured rat cortical neurons and also for antidementia activity in mice. Exposure of cultured cortical neurons to 10 µM Aß (25-35) for 36 h induced neuronal apoptotic death. At concentrations of 1-10 µg/mL, V. amurensis inhibited neuronal death, the elevation of intracellular calcium ([Ca(2+)](i)) and the generation of reactive oxygen species (ROS), all of which were induced by Aß (25-35) in primary cultures of rat cortical neurons. Memory loss induced by intracerebroventricular injection of ICR mice with 16 nmol Aß (25-35) was inhibited by chronic treatment with V. amurensis extract (50 and 100 mg/kg, p.o. for 7 days), as measured by a passive avoidance test. Amurensin G, r-2-viniferin and trans-ɛ-viniferin isolated from V. amurensis also inhibited neuronal death, the elevation of [Ca(2+)](i) and the generation of ROS induced by Aß (25-35) in cultured rat cortical neurons. These results suggest that the neuroprotective effect of V. amurensis may be partially attributable to these compounds. These results suggest that the antidementia effect of V. amurensis is due to its neuroprotective effect against Aß (25-35)-induced neurotoxicity and that the leaf and stem of V. amurensis have possible therapeutic roles for preventing the progression of Alzheimer's disease.

Selected compounds derived from Moutan Cortex stimulated glucose uptake and glycogen synthesis via AMPK activation in human HepG2 cells.

AIM OF THE STUDY: To evaluate the effect of selected compounds derived from Moutan Cortex on glucose uptake and glycogen synthesis associated with AMPK activation in insulin-resistant human HepG2 cell. MATERIALS AND METHODS: The effect of isolated compounds (1-16) on glucose uptake and glycogen synthesis was performed using HepG2 cells. The western blot was used to determine the expression of AMPK and its downstream substrates, ACC, p-ACC, and p-GSK-3beta. RESULTS: The effects of the 16 compounds from Moutan Cortex on glucose metabolism in HepG2 cells under high glucose conditions were evaluated. Compounds 2, 3, and 6 displayed highly potent effects on the stimulation of glucose uptake and glycogen synthesis in human HepG2 cells under high glucose conditions. Compounds 2, 3, and 6 phosphorylate AMPK (AMP-activated protein kinase), and resulted in increased phosphorylation of GSK-3beta and suppression of lipogenic expression (ACC and FAS) in a dose-dependent manner. Compounds 2, 3, and 6 also demonstrated interesting, strong eNOS phosphorylation in human umbilical vein endothelial cells (HUVECs). Compounds 1, 4, 5-12, and 14 displayed considerable effects on hepatic glucose production, AMPK activation, and phosphorylation of GSK-3beta in HepG2 cells under high glucose conditions. CONCLUSIONS: These effects may indicate that the activation of AMPK by the active compounds from Moutan Cortex has considerable potential for reversing the metabolic abnormalities associated with type-2 diabetes.

The antimicrobial activity of compounds from the leaf and stem of Vitis amurensis against two oral pathogens.

Nine compounds isolated from the leaf and stem of Vitis amurensis Rupr. (Vitaceae) were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Streptococcus sanguis, which are associated with caries and periodontal disease, respectively. The results of several antimicrobial tests, including MIC, MBC, and TBAI, showed that three compounds inhibited the growth of the test bacteria at concentrations ranging from 12.5 to 50 microg/mL. Among these compounds, compound 5, trans-epsilon-viniferin, displayed the strongest activity against S. mutans and S. sanguis with MIC values of 25 and 12.5 microg/mL, respectively. This is the first report on the antimicrobial activity of stilbenes and oligostilbenes isolated from the leaf and stem of V. amurensis. Thus, this result suggests that natural antimicrobial compounds derived from V. amurensis may benefit oral health as plaque-control agents for the prevention of dental caries and periodontal disease.

Antioxidant activities of coumarins from Korean medicinal plants and their structure-activity relationships.

The aim of this work was to study the structure-activity relationships of the antioxidant activity of natural coumarins isolated from four Korean medicinal plants (1-17) and four purchased coumarins (18-21). The free radical scavenging and lipid peroxidation assays revealed that five phenolic coumarins, scopoletin (1), aesculetin (2), fraxetin (3), umbelliferone (18) and daphnetin (19), possessed considerable antioxidant activities. The coumarins having a catechol group, 2, 3 and 19, showed significant free radical scavenging activity and inhibitory effects on lipid peroxidation, indicating that the catechol group significantly contributed to the antioxidant activities of coumarins. In contrast, the sugar moiety markedly reduced the activities of coumarin glycosides. The results also demonstrate that the alpha-pyrone ring of coumarins significantly enhanced the capacity of inhibiting oxidative reactions of coumarins.

Protein tyrosine phosphatase 1B inhibitors isolated from Morus bombycis.

Bioassay-guided fractionation of the chloroform-soluble fraction of Morus bombycis, using an in vitro PTP1B inhibitory assay led to the identification of three 2-arylbenzofurans, albafuran A (1), mulberrofuran W (2) and mulberrofuran D (6), along with three chalcone-derived Diels-Alder products, kuwanon J (3), kuwanon R (4), and kuwanon V (5). Compounds 1-6 showed remarkable inhibitory activity against PTP1B with IC(50) values ranging from 2.7 to 13.8 microM. Inhibition kinetics were analyzed by Lineweaver-Burk plots, which suggested that compounds 1-6 inhibited PTP1B in a mixed-type manner. The present results indicate that the respective lipophilic and hydroxyl groups of 2-arylbenzofurans and chalcone-derived Diels-Alder products play an important role in inhibition of PTP1B.

Palbinone and triterpenes from Moutan Cortex (Paeonia suffruticosa, Paeoniaceae) stimulate glucose uptake and glycogen synthesis via activation of AMPK in insulin-resistant human HepG2 Cells.

Moutan Cortex is a well-known herb in traditional Korean, Chinese, and Japanese anti-diabetic formulae. In the current study, we investigated the metabolic effects of isolated triterpenes (1-7) in HepG2 cells under high glucose conditions. These compounds remakably stimulated AMP-activated protein kinase (AMPK), GSK-3beta, and ACC phosphorylation. The compounds also increased glucose uptake and enhanced glycogen synthesis. Among these, compound 1 displayed the greatest potential anti-diabetic activity though the AMPK activation pathway. Compound 1 significantly increased the levels of phospho-AMPK, phospho-ACC, and phospho-GSK-3beta and stimulated glucose uptake and glycogen synthesis in a dose-dependent manner. In conclusion, our results suggest that these compounds, especially compound 1, may have beneficial roles in glucose metabolism via the AMPK pathway.

Inhibitors of aldose reductase and formation of advanced glycation end-products in moutan cortex (Paeonia suffruticosa).

The methanol extract of Moutan cortex (Paeonia suffruticosa) afforded two new compounds, 8-O-benzoylpaeonidanin (1) and 5-hydroxy-3S-hydroxymethyl-6-methyl-2,3-dihydrobenzofuran (2), in addition to 4-O-butylpaeoniflorin (3) as an artifact of the separation, seven monoterpene glycosides (4-10), two monoterpenes (11, 12), four acetophenones (13-16), and two triterpenes (17, 18). The structures of the compounds were determined by spectroscopic methods, and the compounds were evaluated for inhibitory effects against rat lens aldose reductase (RLAR) and advanced glycation end-product (AGEs) formation. Compounds 17 and 18 showed the most potent inhibitory activity against RLAR, with IC(50) values of 11.4 and 28.8 microM, respectively. Compounds 3 and 6 also inhibited RLAR with IC(50) values of 36.2 and 44.6 microM, respectively. The positive control, 3,3-tetramethyleneglutamic acid, had an IC(50) value of 31.8 microM. Compounds 3 and 6 inhibited AGE formation with IC(50) values of 10.8 and 11.3 microM, respectively. Compound 2 had an IC(50) value of 177.0 microM, whereas the positive control, aminoguanidine, had an IC(50) value of 1026.8 microM.

Tyrosinase-inhibitory constituents from the twigs of Cinnamomum cassia.

A methanol extract of the twigs of Cinnamomum cassia was found to possess inhibitory activity against tyrosinase. Purification of the MeOH extract afforded four new phenolics, cassiferaldehyde (6), icariside DC (9), cinnacassinol (10), and dihydrocinnacasside (13), together with 10 known compounds (1-5, 7-12, and 14). The structures of the new compounds were determined by spectroscopic data interpretation. Compounds 1-6 and 8-13 showed strong inhibitory activity against tyrosinase, with IC(50) values ranging from 0.24 to 0.94 mM.

Antioxidant and lipoxygenase inhibitory activity of oligostilbenes from the leaf and stem of Vitis amurensis.

ETHNOPHARMACOLOGICAL RELEVANCE: The root and stem of Vitis amurensis (Vitaceae) have popularly used as traditional medicine for treatment of cancer and various pains in Korea and Japan. Recent studies, its root and stem possess anti-inflammatory, anti-tumor activities, and protective effects against beta-amyloid-induced oxidative stress. AIM OF THE STUDY: This study deals with the isolation, structural identification of the potent bioactive compounds from the leaf and stem, and their antioxidant capacity, as well as anti-inflammatory effect via lipoxygenase inhibitory assay. MATERIALS AND METHODS: All isolated compounds yielded after using column chromatography were identified base on the physico-chemical properties and 1D, 2D NMR spectra. The scavenge ability against DPPH and ABTS(+) radicals, and to inhibit lipid peroxidation, as well as lipoxygenase type I inhibitory activity of all isolates were performed using in vitro assays. RESULTS: Eleven resveratrol derivatives (1-11), including a new oligostilbene cis-amurensin B (9), whose structures were determined on the basis of extensively spectral analyses, were isolated from the leaf and stem of Vitis amurensis. The isolates (1-11) were examined for their antioxidant activities by evaluating scavenge ability against DPPH and ABTS(+) radicals, and to inhibit lipid peroxidation. Stilbenes 1 and 4, and oligostilbenes 5-10 displayed moderate anti-lipid peroxidation activities, but all the isolates exhibited strong ABTS(+) radical scavenging activity in the dose-dependent manner. In addition, the isolates showed stronger inhibitory capacity against soybean lipoxygenase type I than that of baicalein, a positive control. Of the isolates, r-2-viniferin (8) exhibited the strongest scavenging activity against ABTS(+) radical with TEAC value of 5.57, and the most potential inhibitory effect on soybean lipoxygenase with the IC(50) value of 6.39 microM. CONCLUSION: This is the first report on the potential antioxidant and LOX-1 inhibitory effects of oligostilbenes isolated from the leaf and stem of Vitis amurensis. In addition, chemical compositions isolated from the leaf and stem are almost similar to those isolated from the root of Vitis amurensis. Therefore, the results may explain, in part, the uses of the leaf and stem, as well as the root of Vitis amurensis in the Korean traditional medicine.

Inhibition of human low density lipoprotein and high density lipoprotein oxidation by oligostilbenes from rhubarb.

The objective of the present study was to elucidate the beneficial properties of ampelopsine B (1) and epsilon-Viniferin (2), two oligostilbenes isolated from rhubarb, toward cardiovascular disease by protecting human lipoproteins against lipid peroxidation. In low density lipoprotein (LDL) oxidation, both 1 and 2 exert an inhibitory activity against Cu(2+)-, 2,2'-azobis-(2-amidinopropane) hydrochloride (AAPH)-induced, as exhibited by prolongation of lag time from 52 to 118 and 136 min, respectively, and also increasing the lag time 38 to 105 and 128 min in high density lipoprotein (HDL) oxidation for 1 and 2, respectively, at the concentration of 3.0 microM. In generation of thiobarbituric acid reactive substances (TBARS), compounds 1 and 2 inhibited LDL oxidation mediated by either catalytic Cu(2+) or thermo-labile radical initiator (AAPH) in a dose-dependent manner with IC(50) values of 3.6 and 6.0 microM for 1, and 1.7 and 3.2 microM for 2, respectively. In addition, compounds 1-2 also showed strong ability to protect HDL oxidation induced by both Cu(2+) and AAPH with low IC(50) values. The results suggest that oligostilbenes 1-2 may have a role in preventing lipoprotein oxidation.

A phenylpropanoid glycoside with antioxidant activity from Picria tel-ferae.

A phytochemical study on Picria tel-ferae resulted in the isolation of a phenylpropanoid glycoside (1), which was reported for the first time from this plant. The structure of compound 1 was identified as 1-O-3,4-(dihydroxyphenyl)- ethyl-beta-D- apiofuranosyl- (1-->4)-alpha-L-rharmnopyranosyl- (1-->3)-4-O-caffeoyl- beta-D-glucopyranoside on the basis of spectroscopic analyses. In addition, it was found that 1 exhibited a remarkable inhibitory effect on lipid peroxidation initiated by either a free radical [AAPH; 2,2'-azobis-(2-amidinopropane)dihydrochloride] or generated hydroxyl radical (Fe2+/ascorbate). These findings, together with those of previous studies, suggest that P. tel-ferae possesses abundant phenylpropanoid glycosides, and the plant might be used beneficially in the treatment of oxidative stress-related human diseases.