Acylated flavonoid glycosides from Barringtonia pendula and their inhibition on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells.

Six new acylated flavonoid glycosides namely barringosides J - O (1-6) along with tephrokaempferoside and barringoside D were isolated from the branches and leaves of Barringtonia pendula. The structural elucidation was confirmed by extensive analysis of their spectroscopic data including HRQTOFMS, 1D and 2D NMR experiments. Moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells were observed for barringosides M (4) and N (5) with IC50 values of 48.40 ± 3.01 and 56.61 ± 3.87 µM, whereas weak inhibition was found for compounds 1-3, 6, and 7 with IC50 values ranging from 64.91 ± 3.68 to 79.80 ± 3.90 µM.

Phenolic Glycosides from the Leaves of Iodes cirrhosa Turcz. with Cytotoxic and Antimicrobial Effects.

In the present study, 14 phenolic glycosides, including one new neolignan glycoside, iodescirrhoside A (1), three new flavonol glycosides, iodescirrhosides B-D (2-4), and 10 known metabolites were obtained from the methanol extract of Iodes cirrhosa leaves. Structural elucidation was performed by interpretating the 1D- and 2D- NMR, HR-ESI-MS, and CD spectra in comparison with literature data. All compounds were noncytotoxic to LU-1, HepG2, MCF-7, SK-Mel-2, and LNCaP cancer cell lines. Compound 11 significantly inhibited the growth of E. faecalis. In contrast, weak inhibition was observed for 1-9 and 14 against E. faecalis, for 1, 6-8, and 11 against S. aureus, for 6 and 13 against B. cereus, and 2, 4, and 6-9 against C. albicans.

Phenolic glycosides from Oroxylum indicum.

Two new phenolic glycosides, oroxylumosides A (1) and B (2), along with four known compounds darendoside A (3), leucosceptoside A (4), acteoside (5) and decaffeoylacteoside (6) were isolated from the stem bark of Oroxylum indicum. Their structures were elucidated by extensive analysis of the 1 D and 2 D NMR as well as HR-ESI-QTOF-MS. In addition, compounds 1 - 4 exhibited inhibitory effects on NO production in LPS-stimulated BV2 microglial cell line with IC50 values of 58.2 ± 2.9, 70.6 ± 3.5, 56.8 ± 2.8 and 61.1 ± 3.1 µM, respectively.

Cembranoids from the Vietnamese soft coral Sarcophyton ehrenbergi.

Using various chromatographic separations, two new cembranoids, ehrenbergols F and G (1 and 2), along with three known analogs ehrenbergol D (3), (+)-isosarcophine (4) and sinulariol Z2 (5) were isolated from the soft coral Sarcophyton ehrenbergi. The structural elucidation was done by extensive analysis of the 1 D and 2 D NMR, HR-ESI-QTOF-MS as well as CD experiments. In addition, compounds 1 (IC50 of 38.38 ± 2.89 µM), 3 (IC50 of 37.14 ± 3.22 µM) and 4 (IC50 of 45.01 ± 2.49 µM) revealed moderate inhibitory activity on LPS-induced NO production in RAW264.7 cells, whereas 2 (IC50 of 73.32 ± 1.95 µM) and 5 (IC50 of 64.48 ± 4.93 µM) exhibited weak effect.

Four new pregnane glycosides from Gymnema latifolium and their α-glucosidase and α-amylase inhibitory activities.

Four new pregnane glycosides, gymlatifosides A - D (1 - 4) and one known pregnane glycoside, verticilloside J (5) were isolated from the leaves of Gymnema latifolium Wall. ex Wight. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR, HR-ESI-MS, and in comparison with the reported data. All these compounds were tested for α-glucosidase and α-amylase inhibitory activities. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 37.8 ± 1.5% at the concentration of 200 µM. Compounds 1-4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 7.0 to 30.1%. In addition, all compounds 1-5 showed moderate/weak anti α-amylase activity in the investigated test.

Prenylated flavonoids and other constituents from Macaranga indica.

Four new prenylated flavonoids, macarindicins I-IV (1-4) together with ten known compounds, broussoflavonol F (5), vedelianin (6), schweinfurthin E (7), vitexin (8), 2″-rhamnosyl vitexin (9), isovitexin (10), (6R,7E,9R)-9-hydroxy-megastigman-4,7-dien-3-one-9-O-ß-D-glucopyranoside (11), 6S,9R)-roseoside (12), (6S,9S)-roseoside (13), and bridelionoside B (14) were isolated from the leaves of Macaranga indica. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR, and MS data. All the isolated compounds were evaluated for their cytotoxic activities against four human cancer cell lines including KB, MCF-7, HepG-2, and LU. As a result, compound 6 significantly exhibited cytotoxic activity against all tested human cancer cell lines with IC50 values ranging from 4.7 to 11.0 µM. Compounds 2, 5, and 7 showed moderate cytotoxic activity with IC50 values ranging from 7.0 to 38.7 µM.

Cytotoxic and immunomodulatory phenol derivatives from a marine sponge-derived fungus Ascomycota sp. VK12.

Chemical investigation of the marine-derived endophytic fungus Ascomycota sp. VK12 resulted in isolation and identification of a new compound, (3R)-(3',5'-dihydroxyphenyl)butan-2-one (1) and five known ones: AGI-7 (2), sescandelin (3), sescandelin-B (4), 4-hydroxybenzaldehyde (5), and hydroxysydonic acid (6). The absolute configuration of 1 was determined by time-dependent density functional theory electronic circular dichroism, specific optical rotation, and NMR calculations. Compounds 1 and 2 showed cytotoxicity towards HepG2, MCF-7, and SK-Mel2 carcinoma cells, with IC50 values ranging from 48.6 to 96.5 µM. Compounds 1, 2, 4-6 displayed NO inhibitory effects in LPS-stimulated BV2 cells, with IC50 values in a range from 24.2 to 76.5 µM. Compound 2 further inhibited PGE2 overproduction, with an IC50 value of 25.3 µM. The inhibitory effects of 2 towards NO and PGE2 overproduction were found to have a close relationship with its suppression of iNOS and COX-2 protein expression, respectively.

Cytotoxic sesquiterpene glucosides from Fissistigma pallens.

Six undescribed sesquiterpene glucosides, fissispallins A-F, and one known sesquiterpene glucoside, fissispallin, were discovered in the leaves of Fissistigma pallens (Finet & Gagnep.) Merr. The structures were determined using spectroscopic methods, including 1D, 2D NMR, and MS. All compounds were evaluated for cytotoxic activity against three human cancer cell lines, HT-29, A-2058, and A-549. Fissispallin A showed potent activity with the IC50 values less than 1.5 µM against all tested human cancer cell lines. Fissispallin also showed potent activity with IC50 value of 0.4 ± 0.3 on the A-2058 cancer cell lines. Fissispallins B-D showed significant cytotoxic activity against all the tested cancer cell lines with IC50 values ranging from 3.8 to 7.2 µM.

Three new muurolane-type sesquiterpene glycosides from the whole plants of Balanophora fungosa subsp. indica.

Three new muurolane type sesquiterpene glycosides, named balanoindicosides A - C (1 - 3), were isolated from the whole plant of Balanophora fungosa subsp. indica using various chromatographic methods. Their structures were determined by extensive analysis of HR-ESI-MS and NMR spectroscopy. The stereochemistry of muurolane sesquiterpene backbone was demonstrated by NOESY analysis. Configuration of C-12 in compounds 2 and 3 could be distinguished by chemical shift value of C-14. Compounds 1-3 exhibited weak cytotoxic activity towards HepG-2, HL-60, LU-1, and MCF-7 cell lines.

Three new flavonol glycosides from Fissistigma pallens.

Three new flavonol glycosides, fissflavosides A-C (1-3), together with six known flavonol glycosides, kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-galactopyranoside (4), kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-ß-D-galactopyranoside (5), kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranoside (6), rhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranoside (7), rutin (8), and isorhamnetin 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-galactopyranoside (9) were isolated from the methanol extract of the Fissistigma pallens leaves. Their chemical structures were determined by 1D-, 2D-NMR, and MS data as well as in comparison with reported data in the literature. Compounds 1-9 showed weak cytotoxic activity on three human cancer cell lines, HT-29, A-2058, A-549 with IC50 ranging from 134.6 to 162.6 µM. In addition, the antioxidant capacities of compounds were also tested by ORAC assay. All compounds showed significant antioxidant with trolox equivalents ranging from 4.4 to 8.6 µM at the concentration of 1.0 µM. The results indicated 7 and 8 having meaningful reducing capacity of copper (I) ions of 2.7 to 6.9 µM at the concentrations of 1 and 2 µM.

Achievements in the Study of Marine Low-Molecular Weight Biologically Active Metabolites from the Vietnamese Territorial Waters as a Result of Expeditions aboard the Research Vessel 'Akademik Oparin' (2004-2017).

Until 2004, the secondary metabolites of marine organisms of the Vietnamese territorial waters had been studied very poorly. Only four new compounds were isolated from 1977 to 2003. Joint Russian-Vietnamese expeditions aboard the research vessel 'Akademik Oparin' made it possible to study in detail the chemical diversity of marine micro- and macroorganisms. As a result of five expeditions, more than 250 low-molecular weight natural compounds, including 117 new metabolites, were isolated from marine invertebrates and microfilamentous fungi. Their biological activities, such as cytotoxic, cytoprotective, and antioxidant activities, were investigated. Information about the structure and biological activity of the compounds, the source for their isolation and the geographical location of the objects is summarized in this review.

Ethanol extract of Polyscias fruticosa leaves suppresses RANKL-mediated osteoclastogenesis in vitro and LPS-induced bone loss in vivo.

BACKGROUND: Many bone-related diseases such as osteoporosis and rheumatoid arthritis are commonly associated with the excessive activity of osteoclasts. Polyscias fruticosa has been used as traditional medicine for the treatment of ischemia and inflammation and also eaten as a salad. However, its effect on the bone related diseases has not been investigated yet. PURPOSE: This study aimed to investigate the effect of ethanol extract of P. fruticosa on RANKL-induced osteoclastogenesis in vitro and LPS-induced bone loss in mouse, and evaluate anti-osteoclastogenic activities of its major constituents. METHODS: BMMs or RAW264.7 cells were treated with ethanol extract from P. fruticose leaves (EEPL), followed by an evaluation of cell viability, RANKL-induced osteoclast differentiation, actin-ring formation, and resorption pits activity. Effects of EEPL on RANKL-induced phosphorylation of MAPKs were evaluated by Western blotting. The expression levels of NFATc1 and c-Fos were evaluated by Western blotting or immunofluorescence assay. The expression levels of osteoclast-specific marker genes were evaluated by Western blotting and reverse transcription-qPCR analysis. A LPS-induced murine bone loss model was used to evaluate the protective effect of EEPL on inflammation-induced bone loss. HPLC analysis was performed to identify the major constituents of EEPL. RESULTS: EEPL significantly inhibited RANKL-induced osteoclast differentiation by decreasing the number of osteoclasts, osteoclast actin-ring formation, and bone resorption. EEPL suppressed RANKL-induced phosphorylation of p38 and JNK MAPKs, as well as the expression of c-Fos and NFATc1. EEPL decreased the expression levels of osteoclast marker genes, including MMP-9, TRAP and CtsK. Mice treated with EEPL significantly protected the mice from LPS-induced osteoclast formation and bone destruction as indicated by micro-CT and histological analysis of femurs. We also identified 3-O-[ß-d-glucopyranosyl-(1→4)-ß-d-glucuronopyranosyl] oleanolic acid 28-O-ß-d-glucopyranosyl ester (1) and quercitrin (3) as the active constituents in EEPL for inhibiting RANKL-induced osteoclast differentiation. CONCLUSION: The results showed that EEPL exerted anti-osteoclastogenic activity in vitro and in vivo by inhibiting RANKL-induced osteoclast differentiation and function, and suggested that EEPL could have beneficial applications for preventing or inhibiting osteoclast-mediated bone diseases.

Chemical constituents from Vietnamese mangrove Calophyllum inophyllum and their anti-inflammatory effects.

In a search for anti-inflammatory activity in resources from Vietnamese mangroves, we found that a methanolic extract from the leaves of Calophyllum inophyllum (CIL) showed significant anti-inflammatory effects in vitro. Using various chromatographic techniques, we subsequently isolated 12 compounds (1-12) from a methanolic extract of CIL, including two novel compounds (1-2). The inhibitory effects of these compounds on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells were also evaluated. Compound 1 significantly suppressed NO production (IC50 = 2.44 ±â€¯0.88 µM), the secretion of pro-inflammatory cytokines (including interleukin-1 beta and tumor necrosis factor alpha), and the expression of inducible nitric oxide synthase through downregulation of nuclear factor-kappa-B signaling cascades. These results suggest that C. inophyllum leaves might be a useful resource for the development of drugs for the treatment of inflammation.

Ganomycin I from Ganoderma lucidum attenuates RANKL-mediated osteoclastogenesis by inhibiting MAPKs and NFATc1.

BACKGROUND: Many bone-related diseases such as osteoporosis and rheumatoid arthritis are commonly associated with excessive activity of the osteoclast. Ganomycin I (GMI), a meroterpenoid isolated from Vietnamese mushroom Ganoderma lucidum, possesses a variety of beneficial effects on human health. However, its impact and underlying mechanism on osteoclastogenesis remain unclear. In the present study, we investigated the effect of GMI on RANKL-induced osteoclast formation in mouse BMMs and RAW264.7 cells. METHODS: BMMs or RAW264.7 cells were treated with GMI followed by an evaluation of cell viability, RANKL-induced osteoclast differentiation, actin-ring formation, and resorption pits activity. Effects of GMI on RANKL-induced phosphorylation of MAPKs as well as the expression levels of NFATc1 and c-Fos were evaluated by Western blot analysis. Expression levels of osteoclast marker genes were evaluated by Western blot analysis and reverse transcription-qPCR. RESULTS: GMI significantly inhibited RANKL-induced osteoclast differentiation by decreasing the number of osteoclasts, osteoclast actin-ring formation, and bone resorption in a dose-dependent manner without affecting cell viability. At molecular level, GMI inhibited the RANKL-induced phosphorylation of ERK, JNK, and p38 MAPKs, as well as the expression levels of c-Fos and NFATc1, which are known to be crucial transcription factors for osteoclast formation. In addition, GMI decreased expression levels of osteoclastogenesis specific marker genes including c-Src, CtsK, TRAP, MMP-9, OSCAR, and DC-STAMP in RANKL-stimulated BMMs. CONCLUSION: Our findings suggest that GMI can attenuate osteoclast formation by suppressing RANKL-mediated MAPKs and NFATc1 signaling pathways and the anti-osteoclastogenic activity of GMI may extend our understanding of molecular mechanisms underlying biological activities and pharmacological use of G. lucidum as a traditional anti-osteoporotic medicine.

Granulatosides D, E and other polar steroid compounds from the starfish Choriaster granulatus. Their immunomodulatory activity and cytotoxicity.

Two new steroid glycosides, granulatosides D (1) and E (2), belonging to the group of bi- and monoglycosides of polyhydroxysteroids, respectively, were isolated from the ethanolic extract of the starfish Choriaster granulatus along with thirteen previously known glycosides of polyhydroxysteroids (3-15) and one steroid heptaol (16). The structures of the new compounds were elucidated by extensive NMR and ESIMS techniques. Cytotoxic and immunomodulatory activities of compounds 1, 3-8, and 10-16 using murine splenocytes and peritoneal macrophages were studied. At a dose of 0.1 µM new glycoside 1 showed immunomodulatory properties, increasing the intracellular ROS (reactive oxygen species) level in peritoneal murine macrophages by 20% and decreasing intracellular ROS level by 21% in pre-treated with endotoxic lipopolysaccharide from E. coli (LPS) peritoneal macrophages.

Macrolide and phenolic metabolites from the marine-derived fungus Paraconiothyrium sp. VK-13 with anti-inflammatory activity.

Five new secondary metabolites, modiolides D-G (1-4) and 1-(2,5-dihydroxyphenyl)-3-methoxy-butan-1-one (8), one new natural product, 1-(2,5-dihydroxyphenyl)-3-hydroxybutan-1-one (7), along with three known compounds, modiolides A (5) and B (6), and 1-(2,5-dihydroxyphenyl)-2-buten-1-one (9) were isolated from a fermentation culture of the marine endophytic fungus Paraconiothyrium sp. VK-13. Their chemical structures were elucidated by the NMR and MS spectroscopic analysis as well as the modified Mosher's method. Compounds 7 and 9 inhibited the overproduction of proinflammatory mediators NO and PGE2 in LPS-stimulated RAW264.7 cells, with IC50 values ranging from 3.9 to 12.5 µM. The inhibitory effects of 7 and 9 on the release of NO and PGE2 were correlated with their significant suppression of iNOS and COX-2 protein expression, respectively. Furthermore, both compounds 7 and 9 inhibited the mRNA expression of proinflammatory cytokines, including TNF-α, IL-1ß, IL-6, and IL-12, with IC50 values in a range of 2.4-12.5 µM.

Labdane-type diterpenoids from Vitex limonifolia and their antivirus activities.

Phytochemical investigation of the methanol extract of Vitex limonifolia leaves led to the isolation of three new labdane-type diterpenoids, vitexlimolides A-C (1-3) and eight known compounds, 5,4'-dihydroxy-3,7-dimethoxyflavone (4), vitecetin (5), 5,4'-dihydroxy-7,3'-dimethoxyflavone (6), verrucosin (7), 2α, 3α-dihydroxy-urs-12-en-28-oic acid (8), euscaphlic acid (9), 18,19-seco, 2α, 3α-dihydroxy-19-oxo-urs-11,13(18)-dien-28-oic acid (10), and maslinic acid (11). Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for antiviral activities against CVB3, HRV1B, and EV71 viruses. As a result, compounds 4 and 6 showed potent antiviral activity against CVB3 infection with IC50 values of 0.12 ± 0.06 and 1.86 ± 0.18 (µM), respectively.

A new rearranged abietane diterpene from Clerodendrum inerme with antioxidant and cytotoxic activities.

Eight compounds were isolated from the leaves of Clerodendrum inerme, including one new rearranged abietane diterpene, crolerodendrum B (1). Their structures were determined by means of spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance (1-D and 2-DNMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). The DPPH radical scavenging and cytotoxic activities of isolated compounds against MCF7 (breast), HCT116 (colon) and B16F10 (melanoma) cancer cell lines were evaluated. Compounds 1, 3 and 4 exhibited strong DPPH radical-scavenging effects (ED50 values of 17.6 ± 2.1, 10.1 ± 0.8 and 11.3 ± 0.3 µM, respectively) and 4 showed strong cytotoxicity against the HCT116 cell line (IC50 = 3.46 ± 0.01 µM).

Sesquiterpene Quinones and Diterpenes from Smenospongia cerebriformis and Their Cytotoxic Activity.

Using various chromatographic methods, one new sesquiterpene quinone named smenohaimien F (1) and five known, neodactyloquinone (2), dactyloquinone C (3), dactyloquinone D (4), isoamijiol (5), and amijiol (6), were isolated from the marine sponge Smenospongia cerebriformis Duchassaing & Michelotti, 1864. Their structures were elucidated by ID-, 2D-NMR spectroscopic analysis, HR-ESI-MS, and by comparing with the NMR data reported in the literature. The cytotoxic activities of the all compounds were evaluated on five human cancer cell lines, LU-1, HL-60, SK-Mel-2, HepG-2, and MCF-7. Compound 4 was found to exhibit significant cytotoxic activities on all tested human cancer cell lines with IC50 values ranging from 0.7 to 1.6 µg/mL.