Dammarane-type saponins from Gynostemma pentaphyllum.

Seven dammarane glycosides, gypenosides GC1 to GC7, together with ten known compounds, gypenosides V, XIV, XLII-XLVI, gynosaponins TN-1, -2, and gymnemaside VI, were isolated from the methanol extract of the aerial parts of Gynostemma pentaphyllum. Their structures were elucidated by both analysis of 1D and 2D NMR spectra and chemical degradation.

Platelet-activating factor (PAF) receptor binding antagonists from Alpinia officinarum.

The bioassay-guided purification of ether extracts of Alpinia officinarum led to the isolation of two new compounds 6-hydroxy-1,7-diphenyl-4-en-3-heptanone (1) and 6-(2-hydroxy-phenyl)-4-methoxy-2-pyrone (4) as well as three known compounds 1,7-diphenyl-4-en-3-heptanone (2), 1,7-diphenyl-5-methoxy-3-heptanone (3), and apigenin (5). Their structures were established on the basis of spectral methods. All three diarylheptanoids 1, 2, and 3 exhibited potent PAF receptor binding inhibitory activities with an IC(50) of 1.

The inhibitory effect of triterpenoid glycosides originating from Sanguisorba officinalis on tissue factor activity and the production of TNF-alpha.

We examined the inhibitory effects of novel triterpene glycoside compounds [ziyu-glycoside II (ZY-II) and its methyl ester (ZYM-201)], which originated from the roots of sanguisorba officinalis L. (Rosaceae), on tissue factor (TF) activity and tumor necrosis factor (TNF)-alpha production. In in vitro TF activity tests, ZY-II but not ZYM-201 strongly blocked lung TF activity with an IC50 value of 0.

Preventive effect of Ginkgo biloba extract (GBB) on the lipopolysaccharide-induced expressions of inducible nitric oxide synthase and cyclooxygenase-2 via suppression of nuclear factor-kappaB in RAW 264.7 cells.

During our ongoing efforts to identify bioactive natural products with anti-inflammatory activity, we produced an extract from Ginkgo biloba (GBB) which contains higher levels of the active principles terpene and biflavonoid than EGb, the standard commercially available extract. In the present study, we examined and compared the effects of these two extracts on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by the RAW 264.7 macrophage cell line.

Control of cytokine gene expression by PG101, a water-soluble extract prepared from Lentinus lepideus.

A water-soluble extract from Lentinus lepideus mycelium, named PG101, has been shown to control the expression of various cytokines [M. Jin, H.J.

Neuroprotective effects of naturally occurring biflavonoids.

We examined neuroprotective effects of naturally occurring biflavonoids on oxidative stress-induced and amyloid beta peptide-induced cell death in neuronal cells. Among the nine biflavonoids tested, amentoflavone, ginkgetin, and isoginkgetin exhibited strong neuroprotection against cytotoxic insults induced by oxidative stress and amyloid beta, suggesting their therapeutic potential against neurodegenerative diseases, including ischemic stroke and Alzheimer's disease.

Inhibition of calmodulin-dependent protein kinase II by cyclic and linear peptide alkaloids from Zizyphus species.

The effects of sedative peptide alkaloids from Zizyphus species on calmodulin- dependent protein kinase II were investigated. Protein kinase II activity was assayed on the basis of its ability to activate tryptophan 5-monooxygenase as its substrate in the presence of calmodulin. All thirteen alkaloids tested were stronger inhibitors than chlorpromazine (IC50, 98 microM) on calmodulin-dependent protein kinase II.

A new antipsychotic effective neolignan from Firmiana simplex.

A new neolignan, named simplidin was isolated from the the n-butanol extract of stem of Firmiana simplex, together with six known compounds, scopoletin (1), syrigaresinol (2), aquillochin (3), nitidanin (4), tamarixetin 3-rhamnoside (6), and quercitrin (7). On the basis of spectral and chemical evidence, simplidin (5) was determined to be rel-(7R,8R)-4,5,9,9'-tetrahydroxy-3,3'-dimethoxy-7-O-5',8-O-4'-neolignan. All the six compounds were also isolated for the first time from this plant.

G2/M cell cycle arrest and induction of apoptosis by a stilbenoid, 3,4,5-trimethoxy-4'-bromo-cis-stilbene, in human lung cancer cells.

Stilbenoids, including resveratrol (3,5,4'-trihydroxy-trans-stilbene) which is a naturally occurring phytoalexin abundant in grapes and several plants, have been shown to be active in inhibiting proliferation and inducing apoptosis in human cancer cell lines. Using resveratrol as the prototype, we have synthesized various analogs and evaluated their growth inhibitory effects in cultured human cancer cells. In the present study, we show that one of the stilbenoids, 3,4,5-trimethoxy-4'-bromo-cis-stilbene (BCS), was more effective than its corresponding trans-isomer and resveratrol on the inhibition of cancer cell growth.

Tissue factor inhibitory sesquiterpene glycoside from Eriobotrya japonica.

Tissue factor (TF, tissue thromboplastin) is a membrane bound glycoprotein, which accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor for activated factor VII (VIIa). The TF-factor VIIa complex (TF/VIIa) proteolytically activates factors IX and X, which leads to the generation of thrombin and fibrin clots. In order to isolate TF inhibitors, by means of a bioassay-directed chromatographic separation technique, from the leaves of Eriobotrya japonica Lindley (Rosaceae), a known sesquiterpene glycoside (2) and ferulic acid (3) were isolated as inhibitors that were evaluated using a single-clotting assay method for determining TF activity.

Antirheumatoid arthritis effect of Rhus verniciflua and of the active component, sulfuretin.

Oral administration of the MeOH extract of Rhus verniciflua or of an EtOAc fraction containing an EtOAc-soluble portion of the MeOH extract slightly decreased rheumatoid arthritis (RA) and C-reactive protein (CRP) factors in Freund's complete adjuvant reagent FCA-treated rats, indicating that they are active extracts for rheumatoid arthritis, the EtOAc extract being more active. Treatment with these two extracts prevented histological changes such as synovial cell proliferation, inflammatory cell infiltration and fat necrosis compared with an FCA-treated group. Oral administration (30 mg/kg) of sulfuretin and fustin, which were isolated from the EtOAc extract by activity-guided separation, significantly decreased RA and CRP factors, the former being more active than the latter.

Peroxynitrite scavenging activity of lithospermate B from Salvia miltiorrhiza.

Peroxynitrite (ONOO-) is produced by the reaction of superoxide (O2-) with nitric oxide. ONOO- damages proteins through nitration or oxidation. For protection from ONOO- induced protein modifications, ONOO- scavengers should be supplemented.

Eugenol suppresses cyclooxygenase-2 expression in lipopolysaccharide-stimulated mouse macrophage RAW264.7 cells.

Inducible cyclooxygenase (COX-2) has been implicated in the processes of inflammation and carcinogenesis. Thus, the potential COX-2 inhibitors have been considered as anti-inflammatory or cancer chemopreventive agents. In this study, the methanolic extract of the cortex of Eugenia caryophyllata Thunberg (Myrtaceae) was found to potently inhibit the prostaglandin E(2) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.

A new in vitro tissue factor inhibitory triterpene from the fruits of Chaenomeles sinensis.

Tissue factor (TF, tissue thromboplastin) accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor. In order to isolate TF inhibitors from the fruits of Chaenomeles sinensis, an activity-guided purification was carried out to yield four triterpenoid compounds. One compound was new and its structure was elucidated as 28-O-beta- D-glucopyranosyl-2alpha,3beta-dihydroxyolean-12-ene-24,28-dioic acid (2), named chaenomeloside A by means of spectral analysis and chemical conversion.

Tissue factor inhibitory flavonoids from the fruits of Chaenomeles sinensis.

Tissue factor (TF, tissue thromboplastin or coagulation factor III) accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor. In order to isolate TF inhibitors from the fruits of Chaenomeles sinensis, an activity-guided purification utilizing a bio-assay method of prothrombin time prolongation, was carried out to yield five active flavoniods such as hovetrichoside C (1) (IC50 = 14.0 microg), luteolin-7-O-beta-D-glucuronide (3) (IC50 = 31.

Peroxynitrite scavenging activity of herb extracts.

Peroxynitrite (ONOO(-)) is a cytotoxicant with strong oxidizing properties toward various cellular constituents, including sulphydryls, lipids, amino acids and nucleotides and can cause cell death, lipid peroxidation, carcinogenesis and aging. The aim of this study was to characterize ONOO(-) scavenging constituents from herbs. Twenty-eight herbs were screened for their ONOO(-) scavenging activities with the use of a fluorometric method.

Antinociceptive and anti-rheumatoidal effects of Kalopanax pictus extract and its saponin components in experimental animals.

In the present study, we have attempted to elucidate the active components for rheumatoidal arthritis using chloroform (CHCl(3)), ethylacetate (EtOAc) and n-butanol (BuOH) fractions of the methanol extract (MeOH) of Kalopanax pictus. Kalopanaxsaponin-A and -I (KPS-A and -I, hederagenin monodesmoside) were isolated from EtOAc fraction and kalopanaxsaponin-B, -H and -K (KPS-B, -H and -K, hederagenin bisdesmosides) obtained from BuOH fraction, respectively. MeOH extract, EtOAc fraction (250, 500 mg/kg, p.