Inhibitors of inducible nitric oxide synthase expression from<Emphasis Type="Italic">artemisia iwayomogi</Emphasis>

Nitric oxide (NO) is an important bioactive agent that mediates a wide variety of physiological and pathophysiological events. NO overproduction by inducible nitric oxide synthase (iNOS) results in severe hypotension and inflammation. This investigation is part of a study to discover new iNOS inhibitors from medicinal plants using a macrophage cell culture system. Two sesquiterpenes (1 and 2) were isolated from Artemisia iwayomogi (Compositae) and were found to inhibit NO synthesis (IC50 3.64 microg/mL and 2.81 microg/mL, respectively) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Their structures were identified as 3-O-methyl-isosecotanapartholide (1) and iso-secotanapartholide (2). Compounds 1 and 2 inhibited the LPS-induced expression of the iNOS enzyme in the RAW 264.7 cells. The inhibition of NO production via the down regulation of iNOS expression may substantially modulate the inflammatory responses.     

A new sesquiterpene lactone from<Emphasis Type="Italic">Artemisia rubripes</Emphasis> nakai

The chromatographic separation of a methylene chloride extract of Artemisia rubripes led to the isolation of a new sesquiterpene lactone (3), together with four known compounds, a coumarin (2) and three terpenes (1, 4, and 5). Their structures were characterized to be 1beta,6alpha-dihydroxy-4(15)-eudesmene (1), scopoletin (2), 1alpha,4beta-dihydroxy-8alpha-acetoxy-guaia-2,10(14), 11(13)-triene-6,12-olide (3), 1alpha,4beta-dihydroxy-8alpha-acetoxy-guaia-2,9,11(13)-triene-6,12-olide (4), and beta-sitosterol-3-O-beta-D-glycoside (5) by spectroscopic means.     

Sesquiterpenes from <Emphasis Type="Italic">Curcuma comosa</Emphasis>

From the dried rhizomes of Curcuma comosa cultivating in Thailand, 26 known sesquiterpenes were isolated: zederone, zederone epoxide, furanodienone, isofuranodienone, 1(10)Z,4Z-furanodiene-6-one, glechomanolide, dehydrocurdione, neocurdione, curdione, 7α-hydroxyneocurdione, 7β-hydroxycurdione, germacrone-1(10),4-diepoxide, germacrone, 13-hydroxygermacrone, curzerenone, curcolonol, alismol, alismoxide, zedoarondiol, isozedoarondiol, procurcumenol, isoprocurcumenol, aerugidiol, zedoalactone B, curcumenone, and curcumadione. Their structures were elucidated on the basis of physicochemical evidence. Among them, glechomanolide, curzerenone, curcolonol, alismol, alismoxide, and zedoarondiol showed no significant optical activities, so they may be artifact products during the isolation or drying process.     

Extract from <Emphasis Type="Italic">Calotropis procera</Emphasis> latex activates murine macrophages

Calotropis procera latex has long been used in traditional medicines. Extracts from C. procera latex have been reported to have various pharmacological actions, including protection from myocardial infarction, hepatoprotective action, antitumor activity, antinociceptive, and pro- and anti-inflammatory actions. To evaluate the immunomodulatory functions of the water-soluble C. procera extract (CPE), we investigated its ability to activate macrophages—effector cells in inflammatory and immune responses. Intraperitoneal injection of CPE in mice (2 mg/mouse) induced migration of macrophages to the intraperitoneal cavity, confirming the proinflammatory effects of water-soluble CPE. The direct effects of CPE on macrophages were then assessed by measuring the production of nitric oxide (NO) as an indicator for macrophage activation. Addition of CPE (1–10 μg/ml) to the culture medium of the murine monocyte/macrophage cell line RAW264.7 caused an increase in NO production in a time- and dose-dependent manner. CPE-elicited NO production was blocked by application of an inhibitor of inducible nitric oxide synthase (iNOS). Expression of iNOS mRNA was induced by treatment of cultured macrophages with CPE. Injection of CPE in mice also resulted in an increase in plasma NO level. The results suggest that CPE activates macrophages and facilitates NO production via up-regulation of iNOS gene expression. A. l. S. Seddek and M. Elsayed Mahmoud contributed equally to this work.     

The inhibitory principle of lipopolysaccharide-induced nitric oxide production from<Emphasis Type="Italic">inula britannica</Emphasis> var.<Emphasis Type="Italic">chinensis</Emphasis>

A sesquiterpene lactone, 1-O-acetyl-4R,6S-britannilactone (1) isolated from the flowers of Inula britannica L. var. chinensis (Rupr.) Reg. (Compositae), was found as an iNOS inhibitory constituent for the first time with an IC50 value of 22.1 microM which is more potent than the positive control, L-N6-(1-iminoethyl)lysine (IC50 = 33.7 microM). Structure of compound 1 was identified by 1D and 2D NMR experiments and by comparison with the reference standard.     

A new sesquiterpene from <Emphasis Type="Italic">Artemisia vulgaris</Emphasis>

The dichloromethane extract of the air-dried leaves of Artemisia vulgaris afforded a new sesquiterpene 1, caryophyllene oxide, phytyl fatty acid esters, squalene, stigmasterol and sitosterol. The structure of 1 was elucidated by extensive one- and two-dimensional nuclear magnetic resonance spectroscopy.     

Tissue factor inhibitory sesquiterpene glycoside from<Emphasis Type="Italic">Eriobotrya japonica</Emphasis>

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 (Vlla). The TF-factor Vlla complex (TF/Vlla) 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 ofEriobotrya 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. Another sesquiterpene glycoside (1) was also isolated but was inactive in the assay system. Compound3 was yielded by alkaline hydrolysis of compound2. The structures of compounds1, 2, and3 were identified by means of spectral analysis as 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranosyl nerolidol (1), 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyr-anosyl-(1→2)-[α-L-(4-trans-feruloyl)-rhamnopyranosyl-(1→6)]-β-D-glucopyranosyl nerolidol (2) and ferulic acid (3), respectively. Compounds2 and3 inhibited 50% of the TF activity at concentrations of 2 and 369 μM/TF units, respectively.     

Neuraminidase Inhibitors from<Emphasis Type="Italic">Reynoutria elliptica</Emphasis>

In the course of screening neuraminidase inhibitors from herbal medicines, Reynoutria elliptica exhibited high inhibitory activity. Four active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification using sillica gel, Sephadex LH-20 chromatography, and recrystallization. The chemical structures of these compounds were identified as 1,3,8-trihydroxy-6-methylanthraquinone (emodin) 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (emodin 3-methyl ether; physcion), 1,3,8-trihydroxy-6-hydoxymethylanthraquinone (omega-hydroxyemodin), and 3,5,4'-trihydroxystilbene (trans-resvertrol) by spectral data including MS, 1H-, and 13C-NMR. The IC50 values of emodin, emodin 3-methyl ether, omega-hydroxyemodin, and trans-resvertrol were 2.81, 74.07, 10.49, and 8.77 microM, respectively. They did not inhibit other glycosidase such as glucosidase, mannosidase, and galactosidase, indicating that they were relatively specific inhibitors of neuraminidase.     

Inhibition of inducible prostaglandin E<Subscript>2</Subscript> production and cyclooxy-genase-2 expression by curdione from<Emphasis Type="Italic">Curcuma zedoaria</Emphasis>

Overproduction of prostaglandins has been considered in mediation of inflammation and carcinogenic process. On this line, the inhibitors of prostaglandin biosynthetic enzyme cyclooxygenase (COX) have played a role of anti-inflammatory and cancer chemopreventive agents. In our continuous efforts to search anti-inflammatory and chemopreventive agents from natural products, bioassay-guided fractionation led to the isolation of curdione from the rhizome of Curcuma zedoaria with the inhibitory effect on the production of prostaglandin E2 in lipopolysaccharide (LPS)-stimulated mouse macrophage RAW 264.7 cells in a concentration-dependent manner (IC50 = 1.1 microM). Mechanistic studies suggest that the suppression of cyclooxygenase-2 (COX-2) mRNA expression is, at least in part, involved in this inhibitory activity of curdione.     

Essential oil compounds from<Emphasis Type="Italic">Agastache rugosa</Emphasis> as antifungal agents against<Emphasis Type="Italic">Trichophyton</Emphasis> species

The antifungal activities of the essential oil from Agastache rugosa and its main component, estragole, combined with ketoconazole, one of the azole antibiotics commonly used to treat infections caused by Trichophyton species, were evaluated in this study. The combined effects were measured by the checkerboard microtiter and the disk diffusion tests, against T. erinacei, T. mentagrophytes, T. rubrum, T. schoenleinii and T. soudanense. Susceptibility of the five Trichophyton species to the oil alone, or ketoconazole alone, differed distinctly. The fractional inhibitory concentration indices (FICI) of ketoconazole combined with estragole or A. rugosa essential oil, against the tested Trichophyton species, were between 0.05 and 0.27, indicating synergistic effects. These drug combinations exhibited the most significant synergism against T. mentagrophytes, with FICIs of 0.05 and 0.09 for estragole and the essential oil fraction from A. rugosa, respectively. Isobolograms based on the data from checkerboard titer tests also indicated significant synergism between ketoconazole and the Agastache oil fraction or estragole, against the Trichophyton species evaluated. Trichophyton susceptibility to ketoconazole was significantly improved by combination with the Agastache rugosa oil fraction or its main component, estragole.     

Flavonoids from<Emphasis Type="Italic">Spatholobus suberectus</Emphasis>

Two pterocarpans [(6aR,11aR)-maackiain, (6aR,11aR)-medicarpin], one flavanone [(2S)-7-hydroxy-6-methoxy-flavanone], one isoflavan (sativan) and two isoflavones (pseudobaptigenin, genistein) were isolated from the Spatholobus suberectus (Leguminosae). Their chemical structures were determined by comparison of their spectroscopic parameters of CD, EIMS, 1D-NMR and 2D-NMR with those reported in the literatures. All of these compounds are reported for the first time from this plant through the present study.     

Identification of <Emphasis Type="Italic">Curcuma</Emphasis> plants and curcumin content level by DNA polymorphisms in the <Emphasis Type="Italic">trn</Emphasis>S-<Emphasis Type="Italic">trn</Emphasis>fM intergenic spacer in chloroplast DNA

With the goal of developing an accurate plant identification method, molecular analysis based on polymorphisms of the nucleotide sequence of chloroplast DNA (cpDNA) was performed in order to distinguish four Curcuma species: C. longa, C. aromatica, C. zedoaria, and C. xanthorrhiza. Nineteen regions of cpDNA were amplified successfully via polymerase chain reaction (PCR) using total DNA of all Curcuma plants. Using the intergenic spacer between trnS and trnfM (trnSfM), all four Curcuma plant species were correctly identified. In addition, the number of AT repeats in the trnSfM region was predictive of the curcumin content in the rhizome of C. longa.     

Involvement of nitric oxide during<Emphasis Type="Italic">in vitro</Emphasis> fertilization and early embryonic development in mice

Nitric oxide (NO) has emerged as an important intracellular and intercellular messenger, controlling many physiological processes and participating in the fertilization process via the autocrine and paracrine mechanisms. This study investigated whether nitric oxide synthase (NOS) inhibitior (L-NAME) and L-arginine could regulate in vitro fertilization and early embryonic development in mice. Mouse epididymal spermatozoa, oocytes, and embryos were incubated in mediums of variable conditions with and without L-NAME or L-arginine (0.5, 1, 5 and 10 mM). Fertilization rate and early embryonic development were significantly inhibited by treating sperms or oocytes with L-NAME (93. 8% vs 66.3%, 92.1% vs 60.3%), but not with L-arginine. In contrast, fertilization rate and early embryonic development were conspicuously reduced when L-NAME or L-arginine was added to the culture media for embryos. Early embryonic development was inhibited by microinjection of L-NAME into the fertilized embryos in a dose-dependent manner, but only by high concentrations of L-arginine. These results suggest that a moderate amount of NO production is essential for fertilization and early embryo development in mice.     

A polyacetylene and flavonoids from<Emphasis Type="Italic">cirsium rhinoceros</Emphasis>

Cirsium rhinoceros Nakai (Compositae) is a herbaceous perennial native to Korea, whole plant of which has been used in folklore medicine. C. rhinoceros was extracted by a standard extraction procedure. Its n-hexane, CHCl3 and n-BuOH extracts were fractionated by column chromatography to provide a polyacetylene, a coumarin and five flavonoids. Ciryneol C, scopoletin, acacetin, cirsimarin were isolated for the first time from this plant.     

New ceramide from<Emphasis Type="Italic">Alocasia macrorrhiza</Emphasis>

A new ceramide alomacrorrhiza A was isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Its chemical structure was elucidated as (2S,3S,4R)-2N-[(2'R)-2'-hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol based on extensive 1D, 2D NMR, EI-MS, FAB-MS, HR-FAB-MS spectroscopic data and chemical degradation studies.     

<Emphasis Type="Italic">Pulsatilla</Emphasis> saponin D: The antitumor principle from<Emphasis Type="Italic">Pulsatilla koreana</Emphasis>

By bioassay-guided separation, an already known saponin, Pulsatilla saponin D was isolated from the root of Pulsatilla koreana Nakai as a antitumor component when evaluated by in vivo antitumor activity as well as in vitro cytotoxic activity test. It showed potent inhibition rate of tumor growth (IR, 82%) at the dose of 6.4 mg/kg on the BDF1 mice bearing LLC cells.     

A new iridoid and other chemical constituents from<Emphasis Type="Italic">pedicularis kansuensis</Emphasis> forma<Emphasis Type="Italic">albiflora</Emphasis> Li.

A new iridoid (1) and thirteen known compounds 2-14 were isolated from Pedicularis kansuensis forma albiflora Li., and their structures were elucidated by spectroscopic methods including 2D-NMR techniques.     

Antioxidative constituents from<Emphasis Type="Italic">Buddleia officinalis</Emphasis>

Four flavonoids (1-4), a phenylethyl glycoside (5), and a phenylpropanoid glycoside (6) were isolated from the flowers of Buddleia officinalis (Loganiaceae). Their structures were determined by chemical and spectral analysis. Among the isolated compounds, luteolin (1) and acteoside (6) exhibited the most potent antioxidative activity on the NBT superoxide scavenging assay. In addition, compounds 1-6 revealed weak antifungal activity, and no hemolytic activity.     

Di- and sesqui-terpenoids isolated from the pods of<Emphasis Type="Italic">Sindora sumatrana</Emphasis> and their potential to inhibit lipopolysaccharide-induced nitric oxide production

Activity-guided fractionation of the n-hexane and CHCl3-soluble fractions of Sindora sumatrana using a bioassay based on the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production by inducible nitric oxide synthase (iNOS) in murine macrophage RAW 264.7 cells led to the isolation of the known compound, (+)-7beta-acetoxy-15,16-epoxy-3,13(16),14-clerodatriene-18-oic acid (2) as an active constituent. In addition, a new trans-clerodane diterpenoid, (+)-2-oxokolavenic acid (1), together with six known compounds, (+)-3,13-clerodadiene-16,15-olide-18-oic acid (3), (+)-7beta-acetoxy-3,13-clerodadiene-16,15-olide-18-oic acid (4), (+)-7beta-acetoxy-16-hydroxy-3,13-clerodadiene-16,15-olide-18-oic acid (5), beta-caryophyllene oxide (6), clovane-2beta,9beta-diol (7), and caryolane-1,9beta-diol (8) were isolated and found to be inactive. The structure of compound 1 was determined using physical and spectroscopic methods such as 1D and 2D-NMR experiments. The known compounds 2-8 were identified by the spectroscopic data and by comparison with the published values. Of eight isolates (1-8), only compound 2 exhibited an iNOS inhibitory activity with IC50 value of 51.6 microM.     

Antibacterial coumarins from<Emphasis Type="Italic">Angelica gigas</Emphasis> roots

Systematic fractionation of Angelica gigas roots led to the isolation of linear furano(pyrano)coumarins such as bergapten (1), decursinol angelate (2), decursin (3), nodakenetin (4) and nodakenin (5). The antibacterial activities of those compounds against pathogenic bacteria were investigated. Among the compounds tested, decursinol angelate (2) and decursin (3) exhibited significant antibacterial activity against Bacillus subtilis with the minimum inhibitory concentrations (MICs) of 50 and 12.5 microg/mL, respectively.