Identification and Cytotoxic Evaluation of Pregnane Saponins from the Twigs and Leaves of Dregea volubilis.

Four new polyhydroxy pregnane glycosides, named volubilosides G-K (3, 5-7), along with three known secondary metabolites, dregeoside Da1 (1), dregeoside Ka1 (2), and volubiloside E (4) were isolated from the twigs and leaves of Dregea volubilis (DV). The chemical structures of these compounds (1-7) were elucidated using spectroscopic techniques (1D and 2D NMR and HR-ESI-MS analyses) and compared with those in the published literature. Compounds (1-7) were evaluated for cytotoxicity against eight cancer cell lines (MB49, K562, MKN-7, HT29, A549, MCF-7, MDA-MB-231, and HepG2), revealing varying levels of cytotoxic effects with IC50 values ranging from 4.29 to 21.05 µM. The results indicated that compounds 1-7 may serve as potential lead compounds for the discovery and development of novel anti-cancer drugs.

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.

Traphanoside GO1, a new triterpenoid saponin from the aerial parts of Glinus oppositifolius with the inhibitory effect on PGE2 production in LPS-induced HepG2 cells.

A new saponin, 3-O-[α-ʟ-rhamnosyl-(1→3)-ß-D-glucopyranosyl]-28-O-ß-D-glucopyranosyl serjanic acid (Traphanoside GO1, 11) along with eleven compounds (1-10 and 12) were isolated from the aerial parts of Glinus oppositifolius. The structures of all isolates were elucidated by analyzing extensive 1 D- and 2 D-NMR and HR-ESI-MS, comparing with reported literature data. Compounds 7-8, 10-11, and 90% ethanol extract (GOE90) were evaluated for the inhibitory effect on PGE2 production from activated HepG2 cells. Among these, new compound 11 showed the most potent inhibitory activity by suppressing LPS-induced PGE2 production on the HepG2 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.

A new flavan-3-ol and the anti-inflammatory effect of flavonoids from the fruit peels of Wisteria floribunda.

A new flavan-3-ol, (+)-afzelechin 5-O-ß-d-glucopyranoside (2), together with 13 known flavonoids (1, 3-14), was isolated from the fruit peels of Wisteria floribunda. Their structures were assigned by detailed interpretation of NMR, MS, and CD spectroscopic data, as well as by comparing with published reports. The in vitro anti-inflammatory activity of the isolated compounds (1-14) was examined. Among them, compounds 3, 6, and 9 produced highest inhibitory effects on tumor necrosis factor alpha (TNF-α)-induced nuclear factor kappa-B activation in HepG2 cells with IC(50) values of 14.1, 16.5, and 11.9 µM, respectively. With the exception of compound 6, the compounds significantly inhibited the accumulation of pro-inflammatory inducible nitric oxide synthase and cyclooxygenase-2 proteins in TNF-α-stimulated HepG2 cells at a concentration as low as 0.1 µM.

Inhibitory effect on NO production of phenolic compounds from Myristica fragrans.

Three new phenolics: ((7S)-8'-(benzo[3',4']dioxol-1'-yl)-7-hydroxypropyl)benzene-2,4-diol (1), ((7S)-8'-(4'-hydroxy-3'-methoxyphenyl)-7-hydroxypropyl)benzene-2,4-diol (2) and ((8R,8'S)-7-(4-hydroxy-3-methoxyphenyl)-8'-methylbutan-8-yl)-3'-methoxybenzene-4',5'-diol (3), along with four known compounds (4-7) were isolated from the seeds of Myristica fragrans. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells.

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.

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.

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.

Stilbenes and oligostilbenes from leaf and stem of Vitis amurensis and their cytotoxic activity.

Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-epsilon-viniferin (3), gnetin H (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)-ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC(50) values ranging from 15.7 +/- 2.1 to 30.9 +/- 1.8 microM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC(50) values of 30.6 +/- 4.1 and 28.7 +/- 2.81 microM, respectively) and K562 (IC(50) values of 38.6 +/- 0.82 and 24.6 +/- 0.76 microM, respectively). Gnetin H (4) showed only weak cytotoxic activity against L1210 with an IC(50) value of 40.1 +/- 4.23 microM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-epsilon-viniferin (3), (+)-ampelopsin F (7), and piceatannol (9) exhibited no activity on three cancer cell lines.