Pingya Li

Lathyrane-type diterpenoids from the seeds of Euphorbia lathyris

Ten lathyrane-type diterpenoids named Euphorbia Factor L12-L21 (1-10) and twelve known diterpenoids (11-22) were isolated from seeds of Euphorbia lathyris. The structures of these compounds were determined by extensive spectroscopic (UV, IR, HRESIMS, 1D and 2D NMR) analyses. In addition, the configuration of Euphorbia Factor L12 (1) was further confirmed by X-ray crystallographic and circular dichroism (CD) analyses. A putative biogenetic relationship to these compounds was proposed. Cytotoxicity of the isolated compounds against C6 and MCF-7 cell lines were evaluated. Compounds 1, 5, 7, 12 and 17 exhibited considerable cytotoxic activities (IC50 12.4-36.2 μM).

A new antioxidant xanthone from the pericarp of Garcinia mangostana Linn.

The air-dried fruit hulls of Garcinia mangostana Linn. were extracted with 85% ethanol. Furthermore, a new xanthone, 1,3,6-trihydroxy-2,5-bis(3-methylbut-2-enyl)-6′,6′-dimethyl-4′,5′-dihydropyrano[2′,3′ : 7,8]xanthone, along with five known xanthones related to their antioxidant activity was purified by silica gel column chromatography and then identified using spectroscopic methods (1D and 2D NMR, MS). The antioxidant activities were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capability. An activity-guided isolation and purification process were used to identify the components, showing the strong DPPH radical-scavenging activity of G. mangostana.

Dihydrophenanthrenes from the stems and leaves of Dioscorea nipponica Makino

From the CHCl3-soluble portion of the 70% EtOH extract of the stems and leaves of Dioscorea nipponica Makino, two new dihydrophenanthrenes were isolated, 2,7-dihydroxy-3,4,6-trimethoxy-9,10-dihydrophenanthrene (1), 4,4′,7,7′-tetrahydroxy-2,2′,6,6′-tetramethoxy-1,1′-bi-9,10-dihydrophenanthrenyl (2). The structures were determined by means of HRMS, 1H-NMR, 13C-NMR, and HMBC experiments.

Phenanthrene derivatives from the stems and leaves of Dioscorea nipponica Makino.

From the CHCl3-soluble portion of the 70% EtOH extract of the stems and leaves of Dioscorea nipponica Makino, two new phenanthrenes, 7-hydroxy-2,3,5-trimethoxy-9,10-dihydrophenanthrene (1) and 2,2′,7,7′-tetrahydroxy-4,4′,6,6′-tetramethoxy-1,1′-biphenanthrenes (2), as well as three known phenanthrenes, 6-methoxycoelonin (3), 4,7-dihydroxy-2,3,6-trimethoxyphenanthrene (4), and 3,7-dihydroxy-2,4,6-trimethoxyphenanthrene (5), were isolated. The structures were determined by means of HR-MS, 1H NMR, 13C NMR, and HMBC experiments.

A new ocotillol-type triterpenoid saponin from red American ginseng.

A new ocotillol-type triterpenoid saponin, named 20(R)-pseudoginsenoside F11 (1), was isolated along with pseudoginsenoside F11 (2) from red American ginseng. The structure of the new saponin was elucidated as 6-O-[α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranosyl]-dammar-20R, 24R-epoxy-3β, 6α, 12β, 25-tetraol by a combination analysis of NMR and mass spectrometry. The complete signal assignments of the two compounds were carried out by means of 2-D NMR spectral analysis.

Two new ceramides from the fruit pulp of Acanthopanax senticosus (Rupr. et Maxim) Harms

Two new ceramides, (3S,4S,5R)-3-octadecanoylamino-4-hydroxy-5-dodecane-2,3,4,5-tetrahydrofuran (1) and (3S,4S,5R)-3-[(2R)-2-hydroxyhexacosanoylamino]-4-hydroxy-5-[(4E)-dodecane-4-ene]-2,3,4,5-tetrahydrofuran (2), together with eight known compounds, eleutheroside A (3), eleutheroside B (4), eleutheroside E (5), 7-hydroxy-6-methoxy-coumarin (6), 6,7-dimethoxycoumarin (7), 5α,8α-epidioxyergosta-6,22-dien-3-ol (8), stigmasterol (9) and rutin (10), were isolated from the fruit pulp of Acanthopanax senticosus (Rupr. et Maxim) Harms. Their structures were elucidated by means of physicochemical properties and spectroscopic methods (1D, 2D NMR and MS).

Chronic toxicity of ginsenoside Re on Sprague-Dawley rats.

ETHNOPHARMACOLOGICAL RELEVANCE Ginseng has been widely used for hundreds of years in both China and other countries. It is well accepted that the pharmacological effects of ginseng are attributed to ginsenosides. Ginsenoside Re is one of the active ingredients in ginseng. The present study was carried out to characterize the toxicity of ginsenoside Re after repeated oral administration in Sprague-Dawley rats. MATERIALS AND METHODS Rats (60 males, 60 females) were administrated ginsenoside Re orally in 0, 38, 113, or 375 mg/kg/day doses for 26 weeks (n=15/group each sex). Clinical signs, mortality, body weights, feed consumption, urinalysis, hematology, serum biochemistry, gross findings, organ weights and histopathology were examined at the end of the test period, as well as after the 4-week recovery period. RESULTS Ginsenoside Re did not induce death, adverse effects or dose-dependent changes in feed consumption, or body weight gain. Some statistically significant differences were observed in hematological and biochemical parameters, as well as in body weights of rats treated with ginsenoside Re. However, there was no abnormality of any organs noted in both gross and histopathological examinations. CONCLUSIONS Ginsenoside Re is well tolerated up to a 375 mg/kg/day oral dosage level and non-toxic in both male and female rats.

The Activation of Nrf2 and Its Downstream Regulated Genes Mediates the Antioxidative Activities of Xueshuan Xinmaining Tablet in Human Umbilical Vein Endothelial Cells.

Epidemiological studies have verified the critical role that antioxidative stress plays in protecting vascular endothelial cells. The aims of the present study were to investigate the antioxidative activities and differential regulation of nuclear erythroid-related factor 2- (Nrf2-) mediated gene expression by Xueshuan Xinmaining Tablet (XXT), a traditional Chinese medicine with the effect of treating cardiovascular diseases. The antioxidative activities of XXT were investigated using quantitative real-time PCR (qPCR), a PCR array, and western blotting. Our results indicated that XXT exhibited potent antioxidative activities by suppressing the levels of hydrogen peroxide- (H2O2-) induced reactive oxygen species (ROS) in human umbilical vein endothelial cells (HUVECs). We were also conscious of strong Nrf2-mediated antioxidant induction. XXT enhanced the expressions of Keap1, Nrf2, and Nrf2-mediated genes, such as glutamate-cysteine ligase modifier subunit (GCLM), NAD(P)H: quinine oxidoreductase 1 (NQO1), heme oxygenase 1 (HMOX1), and glutathione peroxidase (GPX) in HUVECs. In summary, XXT strongly activated Nrf2 and its downstream regulated genes, which may contribute to the antioxidative and vascular endothelial cell protective activities of XXT.

Two new terpenoid benzoates with antitumor activity from the roots of Ferula dissecta

Two new sesquiterpene benzoates, syreiteate A (1) and syreiteate B (2), were isolated from the roots of Ferula dissecta (Ledeb.) Ledeb. Their structures were elucidated by extensive spectroscopic methods including 1D (1H and 13C) NMR, 2D (HSQC, HMBC, DQF-COSY, and NOESY) NMR, and ESI-TOF-MS. Their configurations were determined on the basis of the analysis of the coupling constants, NOESY correlations, and circular dichroism spectrum. Compounds 1 and 2 showed potent growth inhibitory activity against cervical cancer HeLa cell line with the IC50 values of 13.2 and 19.3 μM, respectively.

A new 3,4-seco-lupane-type triterpenoid from the pulp of Acanthopanax senticosus (Rupr. et Maxim) Harms.

A new triterpenoid, 3,4-seco-lupane-20(29)-ene-3,28-dioic acid (1), together with three known lignans, (−)-schisandrin B (2), (−)-sesamin (3) and (−)-syringaresinol (4), was isolated from the pulp of Acanthopanax senticosus (Rupr. et Maxim) Harms. Their structures were elucidated by means of physicochemical properties and spectroscopic methods (1D, 2D-NMR and MS).