Ilexchinene, a new seco-ursane triterpenoid from the leaves of Ilex chinensis with therapeutic effect on neuroinflammation by attenuating the MAPK/NF-κB signaling pathway.

BACKGROUND: Neuroinflammation is a vital factor participating in the whole pathogenetic process of diverse neurodegenerative disorders, but accessible clinical drugs are still insufficient due to their inefficacy and side effects. Triterpenoids are reported to possess potential anti-neuroinflammatory activities, and the leaves of Ilex chinensis are a commonly used herbal medicine containing many ursane-type and oleanane-type triterpenoids. However, the novel triterpenoids from I. chinensis and their underlying mechanisms are still elusive. PURPOSE: To isolate novel seco-ursane triterpenoids with anti-neuroinflammatory effects from the leaves of I. chinensis and reveal their underlying mechanisms. STUDY DESIGN AND METHODS: The novel compound was purified by column chromatography and identified by comprehensive spectroscopic experiments. The LPS-induced BV-2 cell model and LPS-induced acute murine brain inflammation model were used to assess the anti-neuroinflammatory effect of the structure and further understand its underlying mechanisms by cell viability, ELISA, Western blot analysis, qRT‒PCR analysis, behavior analysis, H&E staining, and immunofluorescence staining experiments. RESULTS: Ilexchinene is a novel ursane-type triterpenoid with a rare 18,19-seco-ring skeleton that was first isolated and identified from I. chinensis. Ilexchinene evidently reduced the overexpression of inflammatory substances in vitro. A mechanistic study suggested that ilexchinene could decrease NF-κB activation to prevent the formation of the NLRP3 inflammasome in the early neuroinflammatory response; in addition, it could prevent the phosphorylation of ERK and JNK. In vivo, ilexchinene remarkably improved LPS-induced mouse behavioral deficits and diminished the number of overactivated microglial cells. Furthermore, ilexchinene evidently diminished the overexpression of inflammatory substances in mouse brains. A mechanistic study confirmed that ilexchinene markedly suppressed the MAPK/NF-κB pathway to relieve the neuroinflammatory response. CONCLUSION: We identified a novel 18,19-seco-ursane triterpenoid from the leaves of I. chinensis and revealed its underlying mechanism of neuroinflammation for the first time. These findings suggest that ilexchinene might possess promising therapeutic effects in neuroinflammation.

Structural characterization and immunological activity of polysaccharides from the tuber of Bletilla striata.

Two water-soluble polysaccharides, BSP-1 and BSP-2, were extracted and purified from the tuber of Bletilla striata. The molecular weights of BSP-1 and BSP-2 were 83.54 kDa and 12.60 kDa, respectively. The composition and proportion of BSP-1 and BSP-2 were mannose and glucose in molar ratios of 4.0:1.0 and 3.0:1.0 respectively. The two polysaccharides had a linear backbone, consisting mainly of repeating ß­1,4­linked d­mannosyl residues and ß­1,4­linked d­glucosyl residues. BSP-1 exhibited immunomodulatory effects by increasing the thymus and spleen indices of immunocompromised model mice.

New triterpenoid saponins from the leaves of Ilex chinensis.

Eight new triterpenoid saponins, including four ursane-type saponins, ilexchinenosides J-M (1-4), and four oleanane-type saponins, ilexchinenosides N-Q (5-8), along with three known triterpenoid saponins (9-11) were isolated from the leaves of Ilex chinensis Sims. Their structures were established by 1D, 2D NMR and MS spectroscopic analyses and through comparisons with known compounds. Moreover, compounds 1, 3, 5, 7-9 and 11 exhibited significant levels of hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays while compound 10 had moderately inhibitory effects on the NO production of lipopolysaccharide (LPS)-induced murine macrophages.

[Chemical constituents from tuber of Bletilla striata].

Eighteen compounds were isolated from the EtOAc soluble fraction of Bletilla striata by various chromatographic techniques, such as silica gel, ODS, Sephadex LH-20, RP-HPLC. Their structures were identified by spectroscopic methods and physicochemical properties, as 5-hydroxy-2-(p-hydroxybenzyl)- 3- methoxybibenzyl(1), shancigusins B(2), shanciguol(3),arundinan(4), 3',5-dihydroxy-2,4-di(p-hydroxybenzyl)-3-methoxybibenzyl(5), arundin(6), 3,3'-dihydroxy-2-(p-hydroxybenzyl)-5-methoxybibenzyl(7), 3, 3'-dihydroxy-2', 6'-bis(p-hydroxybenzyl)-5-methoxybibenzyl(8), 7-hydroxy-2,4-dimethoxyphenanthrene(9), bleformin B(10),nudol(11), 3,7-dihydroxy-2, 4-dimethoxyphenanthrene(12), 2, 7-dihydroxy-4-methoxy-9,10-dihydrophenathrene(13), bleformin D(14), 4,4'-dimethoxy-9,10-dyhydro-[6,1'-biphenanthrene]-2,2',7,7'-tetraol(15),gymconopin C(16),(2,3-trans)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-10-methoxy-2,3,4,5-tetrahydro-phenanthro[2,1-b]furan-7-ol(17),shanciol(18). Among them, compound 1 was a new compound, Compounds 2-6,9,15-18 were isolated from this genus for the first time.

[Studies on glucosyloxybenzyl 2-isobutylmalates of Pleione bulbocodioides].

Ten glucosyloxybenzyl 2-isobutylmalates and one benzyl alcohol glycoside were isolated from the dry tuber of Pleione bulbocodioides, which is a specie of Orchidaceae family and its dry tuber is one of the main sources of traditional Chinese medicine "shanci-gu", by a combination of various column chromatographic methods, including ODS, macroporous adsorbent resin, Sepheadex LH-20, and preparative HPLC. Their structures were identified on the basis of chemical evidences and spectroscopic analysis asloroglossin (1), grammatophylloside A (2), cronupapine (3), (-)-(2R, 3S)-1-(4-ß-D-glucopyranosyloxybenzyl)-4-methyl-2-isobutyltartrate (4), vandateroside II (5), grammatophylloside B (6), bis [4-(ß-D-glucopyranosyloxy) -benzyl] (S) -2-isopropylmalate (7), gymnoside I (8), militarine (9), dactylorhin A (10), gastrodin (11). Compounds 1-7 were isolated from this genus for the firt time.

Anti-inflammatory Hydrolyzable Tannins from Myricaria bracteata.

Twelve hydrolyzable tannins were obtained from the twigs of Myricaria bracteata, including two new hellinoyl-type dimers, bracteatinins D1 (1) and D2 (2); a new hellinoyl-type trimer, bracteatinin T1 (3); two known monomers, nilotinin M4 (4) and 1,3-di-O-galloyl-4,6-O-(aS)-hexahydroxydiphenoyl-ß-d-glucose (5); six known dimers, tamarixinin A (6), nilotinin D8 (7), hirtellins A (10), B (9), and E (8), and isohirtellin C (11); and a known trimer, hirtellin T3 (12). The structures of the tannins were elucidated by spectroscopic data analysis and comparisons to known tannins. All compounds were evaluated as free radical scavengers using 1,1-diphenyl-2-picrylhydrazyl and hydroxy radicals and compared to the activity of BHT and Trolox. Compound 6 showed a significant anti-inflammatory effect on croton oil-induced ear edema in mice (200 mg/kg, inhibition rate 69.8%) and on collagen-induced arthritis in DBA/1 mice (20 mg/kg, inhibition rate 46.0% at day 57).

New triterpenoid saponins from the aerial parts of Comastomapedunculatum.

Three new saikosaponin analogs, comastomasaponins I-K (1-3), were isolated from the aerial portions of Comastomapedunculatum. The structures of these compounds were elucidated on the basis of spectroscopic data analysis, and their nitric oxide production inhibitory activity was evaluated invitro.

[Chemical constituents from Pleione yunnanensis].

This study was to investigate the chemical constituents from pseudobulbs of Pleione yunnanensis, one of the source of traditional Chinese medicine "Shancigu". The chemical constituents were isolated by various chromatography methods, including silica gel, ODS, Sephadex LH-20, and semi-preparative HPLC. Fourteen compounds were isolated and identified from the EtOAc fraction of 90% ethanol extract, including five dihydrophenanthrenes, four bibenzyls, two triterpenoids, and three phenylacrylic acids. Their structures were identified on the basis of the spectral data as 4, 7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (1), 4, 7-dihydroxy-1-(p-hydroxybenzyl)-2-methoxy-9,10-dihydrophenanthrene (2), (2,3-trans)-2-(4-hydroxy-3-methoxyphenyl) -3-hydroxymethyl-10-methoxy-2,3,4,5-tetrahydro-phenanthro[2,1-b]furan-7-ol (3), pleionesin B (4), blestriarene A (5), batatasin III (6), 3, 3'-dihydroxy-2-(p-hydroxybenzyl) -5-methoxybibenzyl (7), 3', 5-dihydroxy-2-(p-hydroxybenzyl) -3-methoxybibenzyl (8), 3,3'-dihydroxy-2,6-bis(4-hydroxybenzyl) -5-methoxybibenzyl (9), triphyllol (10), pholidotin (11), (E) -p-hydroxycinnamic acid (12), (E)-ferulic acid (13), and (E)-ferulic acid hexacosyl ester (14). Compounds 5,10-14 were separated from this plant for the first time.

Hepatoprotective saikosaponin homologs from Comastoma pedunculatum.

Eight new triterpenoid saponins, the saikosaponin homologs comastomasaponins A-H (1-8), as well as a known triterpenoid (9) and eight known saponins (10-17) were isolated from the aerial portions of Comastoma pedunculatum. The structures of these compounds were elucidated spectroscopically, and their hepatoprotective activity and cytotoxic activity were evaluated against five human tumor cell lines in vitro. Compounds 1, 5-12, 14, 15, and 17 exhibited potent hepatoprotective activity, and compound 11 displayed cytotoxic activity against HCT-8, Bel-7402, BGC-825, A549, and A2780 human tumor cell lines.

[Chemical constituents from Pleione bulbocodioides].

Fourteen compoumds were isolated from the ethyl acetate portion of the 95% ethanolic extract of Pleione bulbocodioides by a combination of various chromatographic techniques including silica gel, ODS, macroporous adsorbent resin, Sephadex LH-20, and preparative HPLC, of which ten compoumds were phenanthrenes and dihydrophenanthrenes, two compoumds were bibenzyls, one was lignan and a sterol. Their structures were identified on the basis of spectroscopic data as monbarbatain A(1), 2, 7, 2'-trihy-droxy-4, 4', 7'-trimethoxy-1, 1'- biphenanthrene(2), blestriarene A(3), pleionesin B(4), shanciol H(5), 17-hydroxy-7'-(4'-hy-droxy-3 '-methoxyphenyl)- 4-methoxy-9, 10, 7', 8'-tetrahydrophenanthro[2, 3-b]furan-8'-yl methyl acetate(6), 1-p-hydroxybenzyl-4-methoxy phenanthrene-2, 7-diol(7), 1-p-hydroxybenzyl-4-met-hoxy-9, 10-dihydrophenanthrene-2, 7-diol(8), hircinol(9), coelonin( 10), gigantol(11), batatasin 11 (12), syringaresinol(13) and ergosta4, 6, 8 ( 14) , 22-tetraen-3-one (14). Compounds 1-3, 9, 13 and 14 were isolated from this genus for the first time.

[Determination of dactylorhin A and militarine in three varieties of Cremastrae Pseudobulbus/Pleiones Pseudobulbus by HPLC].

To establish an HPLC method for determination of dactylorhin A and militarine in Cremastrae Pseudobulbus/Pleiones Pseudobulbus. The analysis was achieved on an Alltech Prevail C18 column (4. 6 mm x 250 mm, 5 microm) using a mobile phase of acetonitrile (A), water (B) gradient elution in a total run time of 35 min (0 min, 20:80; 30 min, 55:45; 35 min, 55:45) and a diode array detector was set at 224 nm. The flow rate was 0.8 mL x min(-1). The assay displayed good linearity over the concentration range of 0.257-9.95 microg (r = 0.999 8), and 0.128-10.27 microg (r = 0.999 9), respectively. The average recoveries (n = 9) were 94.70% and 102.8% for dactylorhin A and militarine, respectively. The method is accurate, quick, simple and reproducibility. It can be used for the quality control of Pleione bulbocodioides and Pleione yunnanensis.

[Chemical constituents of n-BuOH extract of Comastoma pedunculatum].

Thirteen compoumds were isolated from the n-BuOH portion of the 70% ethanolic extract of Comastoma pedunculatum by a combination of various chromatographic techniques including silica gel, macroporous adsorbent resin, Sephadex LH-20, and preparative HPLC, of which nine were triterpenoid saponins and four were flavone C-glycosides. Their structures were elucidated by spectroscopic data as saikogenin F (1), 3-O-beta-D-fucopyranosylsaikogenin F (2), clinoposaponin XV (3), saikosaponin A (4), 6"-acetylsaikosaponin A (5), clinoposaponin I (6), bupleuroside I (7) , clinoposaponin XII (8) , saikoponin b3 (9), isovitexin (10) , swertisin (11) , isoorientin (12), 3',4',5-trihydroxy-7-methoxy-6-C-beta-D-glucopyranosyl-flavone (13). Compounds 1-10, 12-13 were all isolated from Comastoma genus for the first time.

New xanthone glycosides from Comastoma pedunculatum.

Five new xanthone glycosides, comastomasides A-E (1-5), were isolated from aqueous ethanol extracts of the aerial portions of Comastoma pedunculatum. The structures of these compounds were elucidated by spectroscopic analysis methods. Compounds 1-5 were evaluated for their hepatoprotective activity and cytotoxicity against four human cancer cell lines by in vitro assays. Among them, compounds 3 and 5 exhibited potent hepatoprotective activity. However, none of the compounds displayed cytotoxic activity.

New triterpenoids from the leaves of Cyclocarya paliurus.

Six new triterpenoids including four new secodammarane triterpenoid glycosides (1-4), an epoxydammarane triterpenoid glycoside (5), and a new secodammarane triterpenoid (6) were isolated from the ethanolic extract of the leaves of Cyclocarya paliurus. The structures of these compounds were elucidated by spectroscopic analysis methods. Compounds 1-6 were evaluated for their inhibitory activities against α-glucosidase, lipase, DPP-IV, and aldose reductase.

[Study on chemical constituents from ethyl acetate extract of Myricaria bracteata].

OBJECTIVE: To study the chemical constituents from the ethyl acetate extract of Myricaria bracteata. METHOD: The chemical constituents were isolated and purified by chromatographic techniques, and their structures were identified by physical characters and spectroscopic analysis. RESULT: Sixteen compounds were isolated from the ethyl acetate portion of the 95% ethanolic extract of Myricaria bracteata, and identified as myricarin (1), myricarin B (2), 3alpha-hydroxytaraxer-14-en-28-oic acid (3), myricadiol (4), trans-ferulic acid 22-hydroxydocosanoic acid ester (5), docosyl-3, 4-dihydroxy-trans-cinnamate (6), dillenetin (7), 3, 5, 4'-trihydroxy-7-methoxyflavone (8), 3, 5, 4'-trihydroxy-7, 3'-dimethoxyflavone (9), methyl 3, 5-dihydroxy-4-methoxybenzoate (10), 3-hydroxy-4-methoxy cinnamic acid (11), sinapaldehyde (12), vanillin (13), syringaldehyde (14), 3, 3', 4'-trimethoxyellagic acid (15), methyl p-hyroxybenzoate (16). CONCLUSION: Compounds 5, 6, 12-16 were isolated from the genus Myricaria for the fist time, all of the compounds were isolated from this plant for the fist time, except for 8 and 9.

[Xanthones of Comastoma pedunlulatum].

The xanthones in the ethyl acetate extract of Comastoma pedunlulatum were investigated. The chromatographic and spectroscopic techniques were used to isolate and identify the constituents. Nine xanthones were isolated from the active parts of the ethyl acetate portion of the 70% ethanolic extract of C. Pedunlulatum, which possess the protective activity against hepatocyte damage caused by DL-GalN, and identified as 1,8-dihydroxy-2,6-dimethoxyxanthone (1), 8-hydroxy-1,2,6-trimethoxyxanthone (2), 1,6,8-trihydroxy-2-methoxyxanthone (3), 1,8-dihydroxy-3,5-dimethoxyxanthone (4), 1-hydroxy-3,5,8-trimethoxyxanthone (5), 1 -hydroxy-3,7-dimethoxyxanthone (6), 1,2,6,8-tetrahydroxyxanthone (7), 1,3,7-trihydroxy4- methoxyxanthone (8), 6,8-dihydroxy-1, 2-dimethoxyxanthone (9). Among them, compounds 6-9 were isolated from the genus Comastoma for the fist time.

Triterpenoids from the roots of Pterospermum heterophyllum Hance.

Two new triterpenoids taraxer-14-ene-1alpha,3beta-diol (1) and 3beta-hydroxytaraxer-14-ene-1-one (2), together with the known triterpenes taraxerol (3), betulin (4), betulinic acid (5), sumaresinolic acid (6), and 5-hydroxy-2-methoxy-1,4-naphthoquinone (7), 5,7-dihydroxy-6,8-dimethylchromone (8), alpha-monpalmitin (9), palmitic acid (10), 6beta-hydroxystigmast-4-en-3-one (11), beta-sitostero1 (12), have been isolated from the petroleum ether fraction of the ethanolic extract of Pterospermum heterophyllum. Their structures were established by spectroscopic methods including IR, MS, 1D, and 2D NMR experiments. Compounds 1-8 were evaluated against several human cancer cell lines. Compound 1 showed in vitro selective cytotoxicity against human lung cancer cell lines (A549) with an IC(50) value of 1.22 microM. Compound 7 showed significant cytotoxicity against the A549, HCT-8, Bel7402, BGC-823, and A2780 cancer cell lines with IC(50) values of 0.21, 0.55, 0.40, 0.59, and 0.34 microM, respectively. However, the other compounds were inactive (IC(50)>10 microM).

[Studies on chemical constituents from roots of Pterospermum heterophyllum].

OBJECTIVE: To study the chemical constituents from the roots of Pterospermum heterophyllum. METHOD: The chemical constituents of P. heterophyllum were isolated and purified by silica gel and sephadex LH-20 column chromatography. Their structures were identified on the basis of spectroscopic data and physicochemical properties. RESULT: Nine compounds were isolated and identified as taraxerol (1), betulin (2), betulinic acid (3), sumaresinolic acid (4), 2-methoxy-5-hydroxy-1, 4-naphthoquinone (5), 5, 7-dihydroxy-6, 8-dimethylchromone (6), alpha-monpalmitin (7), palmitic acid (8), beta-sitosterol (9). CONCLUSION: Compounds 2-7 were isolated from this genus for the first time.