Showing papers in "Planta Medica in 2003"

Antimicrobial and antioxidant activities of three Mentha species essential oils.

Abstract: The present study describes the antimicrobial activity and free radical scavenging capacity (RSC) of essential oils from Mentha aquatica L., Mentha longifolia L., and Mentha piperita L. The chemical profile of each essential oil was determined by GC-MS and TLC. All essential oils exhibited very strong antibacterial activity, in particularly against Esherichia coli strains. The most powerful was M. piperita essential oil, especially towards multiresistant strain of Shigella sonei and Micrococcus flavus ATTC 10,240. All tested oils showed significant fungistatic and fungicidal activity [expressed as minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values, respectively], that were considerably higher than those of the commercial fungicide bifonazole. The essential oils of M. piperita and M. longifolia were found to be more active than the essential oil of M. aquatica. Especially low MIC (4 microL/mL) and MFC (4 microL/mL) were found with M. piperita oil against Trichophyton tonsurans and Candida albicans (both 8 microL/mL). The RSC was evaluated by measuring the scavenging activity of the essential oils on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and OH radicals. All examined essential oils were able to reduce DPPH radicals into the neutral DPPH-H form, and this activity was dose-dependent. However, only the M. piperita oil reduced DPPH to 50 % (IC50 = 2.53 microg/mL). The M. piperita essential oil also exhibited the highest OH radical scavenging activity, reducing OH radical generation in the Fenton reaction by 24 % (pure oil). According to GC-MS and TLC (dot-blot techniques), the most powerful scavenging compounds were monoterpene ketones (menthone and isomenthone) in the essential oils of M. longifolia and M. piperita and 1,8-cineole in the oil of M. aquatica.

Phytoestrogens: recent developments.

Abstract: Phytoestrogens are polyphenolic non-steroidal plant compounds with estrogen-like biological activity. Based on their chemical structure, phytoestrogens can be classified into four main groups, i. e., isoflavonoids, flavonoids, stilbenes, and lignans. For each group, the chemistry, dietary sources and biotransformation of the most interesting compounds will be discussed. Since phytoestrogens are structurally very similar to the estrogen 17beta-estradiol, they may exhibit selective estrogen receptor modulating activities. Therefore, special attention will be given to the hormonal effects of various isoflavonoids, including genistein, daidzein, coumestrol and equol, several prenylated flavonoids, especially 8-prenylnaringenin, and the stilbene resveratrol. Furthermore, their non-hormonal effects will be discussed briefly. Finally, the latest developments on the potential protective properties of phytoestrogens and phytoestrogen-containing foods against hormone-dependent breast and prostate cancers and cardiovascular diseases, and as estrogen replacement therapy for postmenopausal women will be discussed.

Anti-inflammatory compounds of plant origin. Part I. Action on arachidonic acid pathway, nitric oxide and nuclear factor kappa B (NF-kappaB).

Abstract: Over the last 10 years, a significant body of evidence has emerged indicating that chemically diverse classes of naturally-occurring substances derived from higher plants are of potential interest for therapeutic interventions in several inflammatory diseases. Part I of this review article focuses on our current knowledge of the mechanisms by which a large range of plant-derived constituents interfere with three relevant targets involved in the inflammatory process, namely arachidonic acid metabolite pathways, nitric oxide and NF-kappaB, and discusses their potential therapeutic use in the management of relevant inflammatory diseases.

Artemisinin, a novel antimalarial drug: biochemical and molecular approaches for enhanced production.

Abstract: Artemisinin, a sesquiterpene lactone containing an endoperoxide bridge, has been isolated from the aerial parts of Artemisia annua L. plants. It is effective against both drug-resistant and cerebral malaria-causing strains of Plasmodium falciparum. The relatively low yield (0.01-0.8 %) of artemisinin in A. annua is a serious limitation to the commercialization of the drug. Therefore, the enhanced production of artemisinin either in cell/tissue culture or in the whole plant of A. annua is highly desirable. It can be achieved by a better understanding of the biochemical pathway leading to the synthesis of artemisinin and its regulation by both exogenous and endogenous factors. Furthermore, genetic engineering tools can be employed to overexpress gene(s) coding for enzyme(s) associated with the rate limiting step(s) of artemisinin biosynthesis or to inhibit the enzyme(s) of other pathway competing for its precursors. These aspects which may be employed to enhance the yield of artemisinin both in vitro and in vivo are discussed in this review.

Immunomodulatory activities of flavonoids, monoterpenoids, triterpenoids, iridoid glycosides and phenolic compounds of Plantago species.

Abstract: A number of Plantago spp especially P major has long been used in the treatment of diseases such as infection, inflammation and cancer In this study, we evaluated the immunomodulatory activities of five chemical classes of pure compounds obtained from the Plantago genus on human peripheral blood mononuclear cells (PBMC) Studies were conducted on lymphocyte transformation by BrdU immunoassay and secretion of interferon-gamma (IFN-gamma) using an ELISA assay Results showed that the water-soluble compounds, namely aucubin, chlorogenic acid, ferulic acid, p-coumaric acid and vanillic acid, enhanced the activity of human lymphocyte proliferation and secretion of IFN-gamma Among the water-insoluble compounds, with the exception of luteolin, both baicalein and baicalin showed an enhancement of the human PBMC Although oleanolic acid and ursolic acid of the triterpenoids did not significantly affect the proliferation of PBMC, they exhibited a strong stimulation of IFN-gamma secretion Linalool, a monoterpenoid, showed a similar immunomodulatory activity as the triterpenoids The present study concludes that the tested compounds, which possess immunostimulating activities, may contribute to the traditional claims of Plantago-based natural products used in treating cancers and infectious diseases

Antihyperglycemic effect of andrographolide in streptozotocin-induced diabetic rats.

Abstract: The antihyperglycemic action of andrographolide, an active principle in the leaves of Andrographis paniculata (Burm. f.) Nees, was investigated in streptozotocin-induced diabetic rats (STZ-diabetic rats). Oral treatment of andrographolide decreased the plasma glucose concentrations of STZ-diabetic rats in a dose-dependent manner. Similar treatment with andrographolide also decreased the plasma glucose in normal rats and the maximal effect was more marked than that in STZ-diabetic rats. Andrographolide at the effective dose (1.5 mg/kg) significantly attenuated the increase of plasma glucose induced by an intravenous glucose challenge test in normal rats. In the isolated soleus muscle of STZ-diabetic rats, andrographolide enhanced the uptake of radioactive glucose in a concentration-dependent manner. Moreover, the mRNA and protein levels of the subtype 4 form of the glucose transporter (GLUT4) in soleus muscle were increased after repeated intravenous administration of andrographolide in STZ-diabetic rats for 3 days. These results suggest that andrographolide can increase the glucose utilization to lower plasma glucose in diabetic rats lacking insulin.

Antitumor activity of balsam fir oil : production of reactive oxygen species induced by α-humulene as possible mechanism of action

Abstract: The antitumor activity of the essential oil of Abies balsamea (balsam fir oil) was evaluated against several solid tumor cell lines including MCF-7, PC-3, A-549, DLD-1, M4BEU and CT-26. Balsam fir oil was found to be active against all the solid tumor cell lines tested, with GI 50 values ranging between 0.76 and 1.7 mg/mL. The oil was analyzed by GC-MS and the cytotoxicity of each oil constituent was determined. Balsam fir oil is essentially constituted of monoterpenes tau; 96 %) and some sesquiterpenes. All the compounds tested were inactive (tau; 250 microM) except for alpha-humulene (GI50 = 55 to 73 microM) which thus seems responsible for the cytotoxicity of the oil. We also tested the cytotoxicity of caryophyllene oxide, which proved inactive, and gamma-caryophyllene which was found to be active against all solid tumor cell lines tested. We evaluated the effects of balsam fir oil and alpha-humulene on the cellular glutathione (GSH) content and on the production of reactive oxygen species (ROS). Balsam fir oil and alpha-humulene induced a dose- and time-dependent decrease in cellular GSH content and an increase in ROS production. These results suggest that GSH depletion and ROS production may be implicated in the cytotoxicity of alpha-humulene and balsam fir oil.

Tanshinone IIA from Salvia miltiorrhiza inhibits inducible nitric oxide synthase expression and production of TNF-alpha, IL-1beta and IL-6 in activated RAW 264.7 cells.

Abstract: The inhibitory effects of tanshinone IIA, a diterpene isolated from Salvia miltiorrhiza root, on the production of nitric oxide (NO), interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), and the expression of inducible nitric oxide synthase (iNOS) were investigated in activated RAW 264.7 cells. This compound markedly inhibited the production of NO, IL-1beta and TNF-alpha, and suppressed the expression of iNOS in a dose-dependent manner. These results suggest that the traditional use of S. miltiorrhiza as an anti-inflammatory herbal medicine may be explained, in part, by the inhibition of NO, IL-1beta, IL-6 and TNF-alpha production, and expression of iNOS.

Antiallergic activity of ginseng and its ginsenosides.

Abstract: In this study, we measured the antiallergic activities of ginsenosides isolated from the root of Panax ginseng ( Araliaceae), and of their metabolites, as produced by human intestinal bacteria. Compound K, which was identified as a main metabolite, had the most potent inhibitory activity on beta-hexosaminidase release from RBL-2H3 cells and on the PCA reaction. The inhibitory activity of compound K was more potent than that of disodium cromoglycate, one of the commercial anti-allergic drugs. This compound demonstrated a membrane stabilizing action on differential scanning calorimetry. However, compound K did not inhibit the activation of hyaluronidase and did not scavenge active oxygen. These results suggest that the antiallergic action of compound K originates from its cell membrane stabilizing activity and that the ginsenosides of ginseng are prodrugs with extensive antiallergic properties. Abbreviations. compound K:20- O-beta- D-glucopyranosyl-20( S)-protopanaxadiol DNP:dinitrophenol DSCG:disodium cromoglycate DPPC:dipalmitoylphosphatidylcholine DPPH:1,1-diphenyl-2-picrylhydrazyl HSA:human serum albumin IC 50 :50% inhibitory concentration EC 50 :50% effective concentration XOD:xanthine oxidase ICR:Institute of Cancer Research PBS:phosphate buffered saline PCA:passive cutaneous anaphylaxis RAW264.7:mouse monocyte leukemiaRBL-2H3: rat basophil leukemia SD:Sprague-Dawley

Antioxidant activity of maslinic acid, a triterpene derivative obtained from Olea europaea.

Abstract: We investigated the effect of maslinic acid (a triterpene derivative obtained from olive pomace), on the susceptibility of plasma or hepatocyte membranes to lipid peroxidation (LPO), induced respectively by the hydroxyl radical (OH*) generated by Fe2+/H2O2 ex vivo and by the system Fe3+/ascorbate in vitro; moreover, three groups of animals used in the plasma study were pretreated with CCl4 (to generate CCl3-*). Endogenous plasma lipoperoxide levels and susceptibility to LPO were decreased in rats treated with maslinic acid, after exposure to OH* by Fe2+/H2O2 (Fenton reaction). Co-incubation with maslinic acid prevented hepatocyte membrane LPO as shown by the reduction of TBARS. In conclusion, maslinic acid may offer some advantages in the resistance of oxidative stress in the animals.

Cytotoxicity and anti-hepatitis B virus activities of saikosaponins from Bupleurum species

Abstract: Saikosaponins, the main active constituents of Bupleurum spp., have been shown to possess immunomodulatory, hepatoprotective, anti-tumor and anti-viral activities. In this study, saikosaponins a, c and d were evaluated for cytotoxicity and anti-hepatitis B virus ( HBV) activities. Results showed that, with the exception of saikosaponins a and d, HBV-transfected human hepatoma cells (2.2.15 cells) cultured with saikosaponin c showed a significantly lower level of HBeAg in culture medium. Saikosaponin c also possessed activity in inhibiting HBV DNA replication; this inhibitory effect was not due to the cytotoxicity of saikosaponin c or its effect on 2.2.15 cell proliferation. Although saikosaponin d exhibited cytotoxicity on 2.2.15 cells, it failed to inhibit HBV multiplication. The cytotoxicity of saikosaponin d against HepG2 human hepatocellular carcinoma cells was due to the induction of apoptosis through the activation of caspases 3 and 7, which subsequently resulted in poly-ADP-ribose-polymerase (PARP) cleavage. DNA fragmentation was clearly noted at more than 6 h after HepG2 cells exposure to saikosaponin d. The present study concludes that saikosaponin c exhibits anti-HBV activity and saikosaponin d possesses potent cytotoxicity against human hepatocellular carcinoma cells.

Composition and antimicrobial activity of the essential oil of Artemisia absinthium from Croatia and France.

Abstract: The essential oils obtained by steam distillation from the aerial parts of two populations of Artemisia absinthium, from France and from Croatia, were analyzed by GC and GC-MS. The oils of A. absinthium of French origin contain (Z)-epoxyocimene and chrysanthenyl acetate as major components while the oils of Croatian A. absinthium contain mainly (Z)-epoxyocimene and beta-thujone. Analysis of oils before and after anthesis showed some quantitative differences. Analysis of separated leaves and flowering heads showed only few differences among these organs. As they contain no thujone, antimicrobial screening was performed on samples of French origin and showed that A. absinthium oil inhibited the growth of both tested yeasts (Candida albicans and Saccharomyces cerevisiae var. chevalieri).

Coumarins and carbazoles from Clausena excavata exhibited antimycobacterial and antifungal activities.

Abstract: Four known coumarins, dentatin (1), nor-dentatin (2), clausenidin (3) and xanthoxyletin (5), and six known carbazole derivatives, 3-formylcarbazole (6), mukonal (7), 3-methoxycarbonylcarbazole (8), murrayanine (9), 2-hydroxy-3-formyl-7-methoxycarbazole (10) and clauszoline J (11) were isolated from Clausena excavata. Compounds 1 and 6 were first isolated from the crude chloroform extract of the rhizomes. Compounds 1, 2, 3, 6, 7, 8, 10 and 11 showed antimycobacterial activity at a minimum inhibitory concentration (MIC) of 50, 100, 200, 100, 200, 50, 100 and 100 microg/mL, respectively. O-Methylated clausenidin ( 4), prepared from 3, exhibited antimycobacterial activity at MIC 50 microg/mL. Compounds 6, 7, 8 and 10 showed antifungal activity with IC 50 values of 13.6, 29.3, 9.5 and 2.8 microg/mL, respectively. All compounds demonstrated no cytotoxicity against KB and BC-1 cell lines.

Antitussive activity of Stemona alkaloids from Stemona tuberosa.

Abstract: Bioactivity-directed fractionation of the crude extract of Stemona tuberosa led to the isolation and characterization of four new stenine-type Stemona alkaloids, namely tuberostemonine J ( 2), tuberostemonine H ( 3), epi-bisdehydrotuberostemonine J ( 4) and neostenine ( 5), together with the known neotuberostemonine ( 1). These five isolated alkaloids were examined for antitussive activity in guinea pig after cough induction by citric acid aerosol stimulation. In this report, we demonstrated, for the first time, that compounds 1 and 5 showed significant antitussive activities. Further study of the structure-activity relationship on these isolated alkaloids and two synthetic analogues revealed that the saturated tricyclic pyrrolo[3,2,1- jk] benzazepine nucleus is the primary key structure contributing to the antitussive activity and all cis configurations at the three ring junctions are the optimal structure for the antitussive activity of stenine-type Stemona alkaloids.

Purification of gastroprotective triterpenoids from the stem bark of Amphipterygium adstringens; role of prostaglandins, sulfhydryls, nitric oxide and capsaicin-sensitive neurons.

Abstract: In this investigation three bioactive compounds, responsible for the gastroprotective property of Amphipterygium adstringens, were purified from an active dichloromethane fraction. These compounds were 3alpha-hydroxymasticadienonic acid, beta-sitosterol and 3- epi-oleanolic acid. The latter was the most active compound (88.8 % of gastroprotection) followed by 3alpha-hydroxymasticadienoic acid and beta-sitosterol (69.8 and 42.5 % of gastroprotection, respectively). Carbenoxolone was used as positive control and it showed 88.4 % of gastroprotection. Masticadienonic acid was also isolated from the active fraction, but it was unable to inhibit the ethanol-induced gastric lesions. The gastroprotection of the methanol extract was completely inhibited by the pretreatment with l-NAME and attenuated by pretreatment with indomethacin and N-ethylmaleimide. These results suggest that endogenous nitric oxide plays an important role in the gastroprotection of A. adstringens methanol extract on ethanol-induced gastric mucosal lesions and that there is partial participation by prostaglandins and endogenous sulfhydryls. The effect of 3alpha-hydroxymasticadienonic acid was attenuated only by pretreatment with N-ethylmaleimide, indicating that endogenous sulfhydryls (thiols) participate in its gastroprotective mechanism. Capsaicin-sensitive afferent neurons do not participate in the gastroprotection of either the methanol extract or 3alpha-hydroxymasticadienoic acid.

The Antihyperglycaemic Activity of Berberine Arises from a Decrease of Glucose Absorption

Abstract: The mechanism of action of berberine as an antihyperglycaemic agent was investigated in the Caco-2 cell line. Berberine was found to effectively inhibit the activity of disaccharidases in Caco-2 cells. It also decreased sucrase activity after preincubation with Caco-2 cells for 72 hours. However gluconeogenesis and glucose consumption of Caco-2 cells were not influenced. 2-Deoxyglucose transporting through Caco-2 cell monolayers was decreased by berberine but the effect was not statistically significant. These results suggest that the antihyperglycaemic activity of berberine is at least partly due to its ability to inhibit alpha-glucosidase and decrease glucose transport through the intestinal epithelium.

Cytotoxic triterpenoids from the fruits of Zizyphus jujuba.

Abstract: The following eleven triterpenoic acids were isolated from the fruits of Zizyphus jujuba (Rhamnaceae): colubrinic acid, alphitolic acid, 3-O-cis-p-coumaroylalphitolic acid (3), 3-O-trans-p-coumaroylalphitolic acid (4), 3-O-cis-p-coumaroylmaslinic acid, 3-O-trans-p-coumaroylmaslinic acid, betulinic acid (7), oleanolic acid, betulonic acid (9), oleanonic acid and zizyberenalic acid. The in vitro cytotoxicities of the triterpenoic acids against K562, B16(F-10), SK-MEL-2, PC-3, LOX-IMVI, and A549 tumor cell lines were investigated by the sulforhodamin B (SRB) method. Among these compounds, the lupane-type triterpenes, such as compounds 3, 4, 7, and 9, showed high cytotoxic activities. In particular, the cytotoxic activities of 3-O-p-coumaroylalphitolic acids (compounds 3 and 4) were better than those of non-coumaroic triterpenenoids (compounds 7 and 9). These results suggest that the coumaroyl moiety at the C-3 position of the lupane-type triterpene may play an important role in enhancing cytotoxic activity.

Crude extract of Salvia miltiorrhiza and salvianolic acid B enhance in vitro angiogenesis in murine SVR endothelial cell line.

Abstract: Salvia miltiorrhiza (SM) has been used clinically in Asian countries to improve the microcirculation in the human body. Although a pure compound extracted from SM, salvianolic acid B (Sal B), has been reported to be effective against fibrosis and ischemia-reperfusion injury, possibly through its anti-lipid peroxidation action, the effect of SM on angiogenesis remains unclear. It is our interest to investigate the role of SM on the regulation of the angiogenic process. By using the SVR endothelial cell line as an in vitro system, the effects of Sal B on the gene expression of vascular endothelial growth factor (VEGF) and its receptors VEGF-R1, VEGF-R2 were evaluated by morphology, differentiation assay, reverse-transcribed polymerase chain reaction (RT-PCR) and Western blot analysis. The results showed that both the crude extract of SM and the pure compound Sal B had enhancing effects on cell growth and differentiation. The gene expression of matrix metalloproteinase-2 (MMP-2) was up-regulated after Sal B treatment for 2 h, while VEGF and VEGF-R2 gene expression were up-regulated 40 min after Sal B treatment. We conclude that the crude extract of SM and Sal B enhance angiogenic processes on SVR cells through up-regulation of VEGF and VEGF receptors genes.

Reversal of P-glycoprotein-mediated multidrug resistance by protopanaxatriol ginsenosides from Korean red ginseng.

Abstract: The overexpression of P-glycoprotein (Pgp) or the multidrug resistance-associated protein (MRP) confers multidrug resistance (MDR) to cancer cells. MDR cells can be sensitized to anticancer drugs when treated concomitantly with an MDR modulator. In this study, we investigated whether or not ginseng saponins could reverse MDR mediated by Pgp or MRP. The chemosensitization and drug accumulation effects of ginseng saponins such as the total saponin, protopanaxadiol ginsenosides (PDG), protopanaxatriol ginsenosides (PTG), ginsenosides-Rb 1, -Rb 2, -Rc, -Rg 1 and -Re were tested on the daunorubicin- and doxorubicin-resistant acute myelogenous leukemia sublines (AML-2/D100 and AML-2/DX100), which overexpress Pgp and MRP, respectively. PTG showed cytotoxicity in both sublines and was able to reverse resistance in the AML-2/D100 subline in a concentration-dependent manner. Conversely, other ginseng saponins at concentrations less than 300 microg/mL showed neither cytotoxicity nor chemosensitizing activity in both resistant sublines. Flow cytometry analysis showed that the effect of PTG (100 microg/mL) on drug accumulation of daunorubicin in the AML-2/D100 subline was 2-fold higher than that observed in the presence of verapamil (5 microg/mL) and 1.5 times less than cyclosporin A (3 microg/mL). The maximum non-cytotoxic concentrations of PTG did not appear to increase the Pgp levels, which is in contrast to verapamil and cyclosporin A. PTG at 200 microg/mL or more completely inhibited the azidopine photolabeling of Pgp. The results suggest that PTG has a chemosensitizing effect on Pgp-mediated MDR cells by increasing the intracellular accumulation of drugs through direct interaction with Pgp at the azidopine site. In addition, PTG may have a beneficial effect on cancer chemotherapy with respect to the possibility of long-term use without the concern of Pgp activation.

Neuroprotective effects of hydroxysafflor yellow A: in vivo and in vitro studies.

Abstract: Previous work has shown that hydroxysafflor yellow A (HSYA), extracted from Carthamus tinctorius L. markedly extended the coagulation time in mice and exhibited a significant antithrombotic effect in rats. The present study was conducted to demonstrate further its neuroprotective effects on cerebral ischemic injury in both in vivo and in vitro studies. In vivo, male Wistar-Kyoto (WKY) rats with middle cerebral artery occlusion (MCAO) were evaluated for neurological deficit scores followed by the treatment with a single dose of HSYA. Furthermore, the infarction area of the brain was assessed in the brain slices. In vitro, the effect of HSYA was tested in cultured fetal cortical cells exposed to glutamate and sodium cyanide (NaCN) to identify its neuroprotection against neurons damage. The results in vivo showed that sublingular vein injection of HSYA at doses of 3.0 mg/kg and 6.0 mg/kg exerted significant neuroprotective effects on rats with focal cerebral ischemic injury by significantly decreasing neurological deficit scores and reducing the infarct area compared with the saline group, HSYA at a dose of 6.0 mg/kg showed a similar potency as nimodipine at a dose of 0.2 mg/kg. Sublingular vein injection of HSYA at the dose of 1.5 mg/kg showed a neuroprotective effect, however, with no significant difference when compared with the saline group. Results in vitro showed that HSYA significantly inhibited neuron damage induced by exposure to glutamate and sodium cyanide (NaCN) in cultured fetal cortical cells. Noticeably, the neuroprotective action of HSYA on glutamate-mediated neuron injury was much better than that of HSYA on NaCN-induced neuron damage. All these findings suggest that HSYA might act as a potential neuroprotective agent useful in the treatment in focal cerebral ischemia. Abbreviations. HSYA:hydroxysafflor yellow A TTC:2,3,5-triphenyltetrazolium chloride MTT:3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide DMEM:Dulbecco's modified Eagle medium FCS:Fetal calf serum MCAO:middle cerebral artery occlusion ECA:external carotid artery ICA:internal carotid artery LDH:lactate dehydrogenase NMDA: N-methyl- D-aspartate

A new anti-HIV flavonoid glucuronide from Chrysanthemum morifolium.

Abstract: A new flavonoid glucuronide, apigenin 7-O-beta-D-(4'-caffeoyl)glucuronide (1), and the known compound, apigenin 7-O-beta-D-glucurnoide, were isolated from the flowers of Chrysanthemum morifolium, along with five known flavonoids. The structure of 1 was elucidated by the aid of spectroscopic analyses. Among isolated compounds, apigenin 7-O-beta-D-(4"-caffeoyl)glucuronide showed strong HIV-1 integrase inhibitory activity (IC (50) = 7.2 +/- 3.4 microg/ml) and anti-HIV activity in a cell culture assay (EC (50) = 41.86 +/- 1.43 microg/ml) using HIV-I (IIIB) infected MT-4 cells.

Effect of limonin and nomilin on HIV-1 replication on infected human mononuclear cells.

Abstract: In the last years several plant-derived natural compounds have been screened for their anti-HIV activity in order to find lead compounds with novel structures or mechanisms of action. Among these, several triterpenoids have been found to exhibit an antiretroviral activity with different mechanisms of action. In this study the effect of two limonoids, limonin and nomilin, on the growth of human immunodeficiency virus-1 (HIV-1) in culture of human peripheral blood mononuclear cells (PBMC) and on monocytes/macrophages (M/M) is described. Limonin and nomilin were found to inhibit the HIV-1 replication in all cellular systems used. A dose-dependent inhibition of viral replication was observed in PBMC isolated from healthy donors and infected with HIV-1 strain after incubation with limonin and nomilin (EC (50) values: 60.0 microM and 52.2 microM, respectively). The two terpenoids inhibited at all concentrations studied the production of HIV-p24 antigen even when the PBMC employed were chronically infected (EC (50) values of 61.0 microM for limonin and 76.2 microM for nomilin). Moreover, these compounds inhibited the HIV-1 replication even in infected M/M. In this cellular system the inhibitory effect was significant at the concentrations of 20 microM, 40 microM and 80 microM starting from day 14 and reached the maximum effect after 18 days of incubation. As regards the mechanism of action, limonin and nomilin inhibit in vitro HIV-1 protease activity. In general, the results obtained point out a similar anti-HIV activity of limonin and nomilin indicating that this activity is not drastically influenced by the structural difference between the two compounds.

Simultaneous analysis of seventeen chemical ingredients of Ligusticum chuanxiong by on-line high performance liquid chromatography-diode array detector-mass spectrometry.

Abstract: An on-line high performance liquid chromatography (HPLC)-diode array detector (DAD)-mass spectrometry (MS) analytical method has been developed to simultaneously separate and identify seventeen main constituents of Chuanxiong ( Ligusticum chuanxiong Hort.), a traditional Chinese medicinal herb. In three Chuanxiong samples, nine compounds were unequivocally determined as vanillin (1), ferulic acid (2), senkyunolide I (4), senkyunolide H (5), senkyunolide A (6), coniferyl ferulate (7), Z-ligustilide (8), neocnidilide (9) and 3-butylidenephthalide (10) by comparing their t R, UV, and MS data with those obtained for the authentic compounds. Furthermore, additional eight compounds were tentatively identified as senkyunolide J (11), senkyunolide F (12), 3-butylphthalide (13), cnidilide (14), riligustilide (15) or Z,Z'-6,8',7,3'-diligustilide (16), tokinolide B (17), levistolide A (18) and senkyunolide P (19), based on their MS data and the comparison of their UV spectra with the published references. This is the first report to describe the development of an on-line HPLC-DAD-MS method to simultaneously analyse seventeen main constituents present in Chuanxiong and to construct the chemical profiles of various Chuanxiong samples.

Growth and ginsenoside production in hairy root cultures of Panax ginseng using a novel bioreactor.

Abstract: We tested the effect of three variables: the bioreactor system (Wave or Spray reactor), medium exchange and culture period, on the capacity of a selected hairy root line of Panax ginseng to produce ginsenosides. Among the reactors, the Wave bioreactor appeared to be the most efficient in promoting hairy root line growth. Periodic exchanges of the medium and a longer culture period increased the growth rate of cultured hairy root line and, consequently, its capacity to produce ginsenosides. Under established optimum conditions (medium exchange every 14 days over a culture period of 56 days using the Wave bioreactor), the initial root fresh weight was enhanced more than 28-fold, giving a root biomass of 284.9 g L(-1) and a ginsenoside content of 145.6 mg L(-1). It is noteworthy that this ginsenoside production exceeded by almost 3-fold that obtained during the shake flask culture of our hairy root line, although it often happens that the scale-up from shake flask to a bioreactor culture results in reduced productivities. To our knowledge this is the first time that a Wave bioreactor has been used for hairy root culture.

In vivo anti-inflammatory and antinociceptive effects of liriodendrin isolated from the stem bark of Acanthopanax senticosus.

Abstract: In the present study, liriodendrin isolated by activity-guided fractionation from the ethyl acetate (EtOAc) extracts of the stem bark of Acanthopanax senticosus, was evaluated for anti-inflammatory and antinociceptive activities. Liriodendrin (5, 10 mg/kg/day, p. o.) significantly inhibited the increase of vascular permeability induced by acetic acid in mice and reduced an acute paw edema induced by carrageenan in rats. When the analgesic activity was measured by the acetic acid-induced writhing test and hot plate test, liriodendrin showed a dose-dependent inhibition in animal models. In addition, syringaresinol, the hydrolysate of liriodendrin, more potently inhibited the LPS-induced production of NO, PGE 2 and TNF-alpha production of macrophages than liriodendrin. Consistent with these observations, the expression level of iNOS and COX-2 enzyme was decreased by syringaresinol in a concentration-dependent manner. These results suggest that the anti-inflammatory and antinociceptive effects of liriodendrin after oral administration were attributable to the in vivo transformation to syringaresinol, which may function as the active constituent.

Antimicrobial constituents from goldenseal (the Rhizomes of Hydrastis canadensis) against selected oral pathogens.

Abstract: Two new C-methyl flavonoids, 6,8-di- C-methylluteolin 7-methyl ether (1) and 6- C-methylluteolin 7-methyl ether (2), were isolated from a commercially available sample of the roots of Hydrastis canadensis, along with seven known compounds, berberine (3), beta-hydrastine (4), canadine (5), canadaline (6), isocorypalmine (7), canadinic acid (8), and beta-sitosterol 3- O-beta- D-glucoside (9). The structures of the new compounds 1 and 2 were elucidated on the basis of their spectral data including 1D and 2D NMR techniques. Of these isolates, berberine (3) and, to a lesser extent, 1 and 2, showed antimicrobial activity when evaluated against the oral pathogens Streptococcus mutans and Fusobacterium nucleatum. Berberine (3) exhibited an additive antimicrobial effect when tested against S. mutans in combination with 1.

Gene expression changes in the human fibroblast induced by Centella asiatica triterpenoids.

Abstract: The molecular pathways underlying the diverse biological activity of the triterpeniod compounds isolated from the tropical medicinal plant Centella asiatica were studied with gene microarrays and real-time reverse transcription polymerase chain reaction (real-time RT-PCR) to quantify the expression of 1053 human genes in human fibroblasts. Fibroblast cells grown in culture were used as a model system to evaluate the stimulation of wound healing by titrated extract from Centella asiatica (TECA) as well as by the four principal triterpenoid components of Centella. TECA treatment effects the expression of genes involved in angiogenesis and the remodeling of extracellular matrix, as well as diverse growth factor genes. The extent of expression change of TNFAIP6, an extracellular hyaluronan binding protein, was found to be largely dose-dependent, to respond most strongly to the free acids asiatic acid and madecassic acid, and to increase in expression over 48 hours of treatment. These results show that Centella triterpenes evoke a gene-expression response consistent with their prevailing medical uses in the treatment of connective tissue disorders such as wound healing and microangiopathy. The identification of genes modulated by these compounds provides the basis for a molecular understanding of Centella's bioactivity, and opportunities for the quantitative correlation of this activity with clinical effectiveness at a molecular level.

The vasorelaxant activity of marrubenol and marrubiin from Marrubium vulgare.

Abstract: Crude extracts of the aerial parts of Marrubium vulgare show a potent in vitro inhibition of KCl-induced contraction of rat aorta. Bio-guided fractionations, spectroscopic analysis and chemical derivatization revealed the furanic labdane diterpenes marrubenol and marrubiin as the most active compounds.

Cytotoxic activity and G2/M cell cycle arrest mediated by antofine, a phenanthroindolizidine alkaloid isolated from Cynanchum paniculatum.

Abstract: Starting with an extract derived from the root of Cynanchum paniculatum Kitagawa (Asclepiadaceae) that was active in the process of inhibiting the growth of human cancer cells in culture, a phenanthroindolizidine alkaloid antofine was isolated and identified as an active principle (IC 50 = 7.0 ± 0.2 ng/ml for A549, human lung cancer cells; IC 50 = 8.6 ± 0.3 ng/ml for Col2, human colon cancer cells). Prompted by the high potency of cancer cell growth inhibition, additional action mechanism studies were performed with antofine. Utilizing cultured Col2 cells as a model, antofine induced arrest in the G2/M phase of the cell cycle after 48 h of incubation. With wash-out experiment, colony formation was also inhibited in a dose-dependent manner. These data suggest the potential of antofine to serve as a cancer chemotherapeutic agent by virtue of arresting the cell cycle.

New antimicrobial alkaloids from the roots of Polyalthia longifolia var. pendula.

Abstract: Bioassay-guided isolation studies on the root extract of Polyalthia longifolia var. pendula possessing significant antibacterial activity led to the isolation of three new alkaloids pendulamine A (1), pendulamine B (2) and penduline (3) along with stigmasterol 3-O-beta-D-glucoside, allantoin, the known diterpenoid kolavenic acid, and the azafluorene alkaloid isoursuline. The structures of these compounds have been elucidated with the help of spectroscopic studies including 2D NMR experiments. Compounds 1 and 2, which are the only protoberberine alkaloids having a monosubstituted A ring with a hydroxy group at C-3, were found to be the active antibacterial principles of the roots. Their MIC values ranged between 0.02-20 microg against the tested bacteria.