Li-Xia Chen

ent-Labdane Diterpenoid Lactone Stereoisomers from Andrographis paniculata

Two pairs of ent-labdane diterpenoid lactone stereoisomers (1- 4) including three new compounds (1- 3) were isolated from the 85% EtOH extract of the aerial parts of Andrographis paniculata. The structures of these compounds were identified as 7 R-hydroxy-14-deoxyandrographolide (1), 7 S-hydroxy-14-deoxyandrographolide (2), 12 S,13 S-hydroxyandrographolide (3), and 12 R,13 R-hydroxyandrographolide (4) by spectroscopic data analyses and calculated (13)C NMR data at the B3LYP/6-311++G(2d,p)//B3LYP/6-31G* level using the GIAO method. The 12 S-configuration of 4 was revised to 12 R based on the spectroscopic data. The antiproliferative activities of the two pairs of stereoisomers and 14 other ent-labdane diterpenoid derivatives were determined in human leukemia HL-60 cells. Andrographolide (7) and isoandrographolide (12) exhibited higher antiproliferative activities than other ent-labdane diterpenoids with GI 50s of 9.33 and 6.30 microM, respectively.

Diarylheptanoids from Curcuma kwangsiensis and their inhibitory activity on nitric oxide production in lipopolysaccharide-activated macrophages.

Eleven diarylheptanoids (1-11) were isolated from rhizomes of Curcuma kwangsiensis, together with seven known compounds. Their structures were elucidated by 1D and 2D NMR, circular dichroism (CD), and accurate mass measurements. Inhibitory effects of the isolated compounds on nitric oxide production in lipopolysaccaride-activated macrophages were evaluated. Compounds 1, 2, and 3 showed strong inhibitory activity on NO production with IC(50) values of 3.13, 2.81 and 2.41 μM, respectively.

Monoterpenes from Paeonia albiflora and their inhibitory activity on nitric oxide production by lipopolysaccharide-activated microglia.

Eleven new monoterpenes, paeonidangenin (1), paeonidanin A (2), paeonidanin B (3), paeonidanin C (4), paeonidanin D (5), paeonidanin E (6), paeoniflorone (7), 4-O-methylbenzoylpaeoniflorin (8), 4-O-methylgalloylpaeoniflorin (9), 4-O-methyldebenzoylpaeoniflorin (10), and 4-O-methylalbiflorin (11), were isolated from the 60% ethanol extract of the roots of Paeonia albiflora. Their structures were determined primarily on the basis of 1D and 2D NMR techniques and MS studies. Paeonidanins D (5) and E (6) are unprecedented examples of cage-like monoterpene dimers. The inhibitory effects of the isolated compounds on nitric oxide production by lipopolysaccharide (LPS)-activated N9 microglia were evaluated.

Two New Megastigmane Glycosides, Physanosides A and B, from Physalis alkekengi L. var. franchetii, and Their Effect on NO Release in Macrophages

Two new megastigmane glycosides, physanosides A and B (1 and 2, resp.), were isolated from Physalis alkekengi L. var. franchetii, together with four known compounds (6S,9R)‐roseoside (3), (6S,9S)‐roseoside (4), (6R,9S)‐3‐oxo‐α‐ionol β‐D‐glucopyranoside (5), and citroside A (6). Their structures were elucidated on the basis of physicochemical evidence, in‐depth NMR spectroscopic analysis, high‐resolution mass spectrometry, and CD spectroscopy, and their inhibitory effect on NO production was also examined. Compounds 2 and 3 exhibited strong inhibition on lipopolysaccharide‐induced NO release by macrophages with IC50 values of 9.93 and 7.31u2005μM, respectively.

Triterpenoids and Flavonoids from Celery (Apium graveolens)

Three new triterpenoids, 11,21-dioxo-2beta,3beta,15alpha-trihydroxyurs-12-ene-2-O-beta-D-glucopyranoside (1), 11,21-dioxo-3beta,15alpha,24-trihydroxyurs-12-ene-24-O-beta-D-glucopyranoside (2), and 11,21-dioxo-3beta,15alpha,24-trihydroxyolean-12-ene-24-O-beta-D-glucopyranoside (3), and two new flavonoids, apigenin-7-O-[2-O-(5-O-feruloyl)-beta-D-apiofuranosyl]-beta-D-glucopyranoside (4) and chrysoeriol-7-O-[2-O-(5-O-feruloyl)-beta-D-apiofuranosyl]-beta-d-glucopyranoside (5), were isolated from the whole plant of fresh celery (Apium graveolens), together with 10 known flavonoids. The structures of the new compounds were elucidated by analysis of spectroscopic data. The inhibitory effects of the compounds isolated on nitric oxide production in lipopolysaccaride-activated macrophages were evaluated.

Guaiane-type sesquiterpenes from Curcuma wenyujin and their inhibitory effects on nitric oxide production

Four new guaiane-type sesquiterpenes (1S,4S,5S,10R)-zedoarondiol, zedoalactones D, E, and F (1–4), along with 10 known ones (5–14), were isolated from Curcuma wenyujin Y.H. Chen et C. Ling. The structures of these new compounds were elucidated by spectroscopic methods. The inhibitory effects of compounds 1–14 on nitric oxide production in lipopolysaccharide-activated macrophages were evaluated. Four new guaiane-type sesquiterpenes (1S,4S,5S,10R)-zedoarondiol, zedoalactone D, E, and F (1–4) were isolated from Curcuma wenyujin Y.H. Chen et C. Ling. Their inhibitory effects on nitric oxide production in lipopolysaccharide-activated macrophages were evaluated. Yan Lou, Feng Zhao, Hao He, Kai-Feng Peng, Xiao-Hua Zhou, Li-Xia Chen and Feng Qiu Guaiane-type sesquiterpenes from Curcuma wenyujin and their inhibitory effects on nitric oxide production

Inactivation of PI3K/Akt signaling mediates proliferation inhibition and G2/M phase arrest induced by andrographolide in human glioblastoma cells.

AIMSnAndrographolide, a principal diterpenoid lactone isolated from the traditional herbal medicine Andrographis paniculata, has been reported to show anti-tumor activity. Since the high lipid solubility of andrographolide permits it to penetrate the blood-brain barrier and concentrate in the brain, we hypothesized that andrographolide may be a potential chemotherapeutic agent for the treatment of glioblastomas. To clarify this point, we investigated the growth inhibitory effect and mechanisms of actions of andrographolide on human glioblastoma U251 and U87 cells.nnnMAIN METHODSnMTT assay and trypan blue exclusion assay were used to investigate the proliferation inhibitory and cytotoxic effects of andrographolide, respectively. Cell cycle distribution was analyzed using flow cytometry. Apoptosis analysis proceeded by detecting the cleavage of caspase-3. The levels of proteins were probed by Western blotting.nnnKEY FINDINGSnThe results showed that non-toxic concentrations of andrographolide inhibited the proliferation of human glioblastoma cells through induction of G2/M arrest, which was accompanied by down-regulating Cdk1 and Cdc25C proteins. Additionally, andrographolide decreased the activity of PI3K/Akt signaling, as demonstrated by down-regulation of the expression of phos-PI3K, phos-Akt, phos-mTOR and phos-p70s6k in U251 and U87 cells. Furthermore, additive effects on the proliferation inhibition, G2/M arrest and down-regulation of G2/M phase-related proteins were observed, when a combined treatment of andrographolide with PI3K inhibitor LY294002 was used in U251 and U87 cells.nnnSIGNIFICANCEnWe prove that andrographolide inhibits the proliferation of human glioblastoma cells via inducing G2/M arrest, which is mediated by inhibiting the activity of PI3K/Akt signaling.

Four new sesquiterpenes from Curcuma wenyujin and their inhibitory effects on nitric-oxide production.

Four new sesquiterpenes including the novel sesquiterpene lactone (6R)‐dehydroxysipanolinolide (1), two new eudesmane‐type sesquiterpenes, curcolide (2) and curcodione (3), and a new xanthane‐type sesquiterpene, curcumadionol (4), were isolated from Curcuma wenyujin Y.u2005H. Chen et C. Ling, together with five known ones, 5–9. The structures of the new compounds were elucidated by spectroscopic methods. The inhibitory effects of compounds 1–9 on nitric‐oxide production in lipopolysaccaride‐activated macrophages were evaluated.

Two new ent-labdane diterpenoid glycosides from the aerial parts of Andrographis paniculata

Two new ent-labdane diterpenoid glycosides were isolated from the aerial parts of Andrographis paniculata. Their structures were elucidated as 3-O-β-d-glucosyl-14-deoxyandrographiside (1) and 3-O-β-d-glucosyl-14-deoxy-11,12-didehydroandrographiside (2) by means of 1D and 2D NMR spectral and chemical methods.

Monoterpenoid inhibitors of NO production from Paeonia suffruticosa

Three pairs of monoterpene glycosides (1-6), of which compounds 1, 3, and 4 as new compounds, together with one new monoterpene (7) were obtained from the ethanol extract of Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectral data. On this basis, the spectral characteristics of three pairs of monoterpene glycosides were also discussed. The inhibitory effects of isolated compounds on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated, and NO production was suppressed significantly by compounds 4-7.