Studies on Bignoniaceae: Newbouldiosides D - F, Minor Phenylethanoid Glycosides from Newbouldia laevis, and New Flavonoids from Markhamia zanzibarica and Spathodea campanulata.

Continued examination of the stem bark of Newbouldia laevis afforded three minor phenylethanoid glycosides, designated as newbouldiosides D - F. Their structures were elucidated by spectroscopic methods as ß-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-ß-D-apiofuranosyloxy-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 3)]-6-O-E-sinapoyl-ß-D-glucopyranoside, ß-(3,4-dihydroxyphenyl)ethyl ß-D-apiofuranosyloxy-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 3)]-6-O-E-sinapoyl-ß-D-glucopyranoside, and ß-(3,4-dihydroxyphenyl)ethyl ß-D-apiofuranosyloxy-(1 → 2)-O-α-L-rhamnopyranosyl-(1 → 2)-6-O-E-sinapoyl-ß-D-glucopyranoside, respectively. These metabolites are the first members possessing a sinapoyl structural element. In addition, the series of naturally occurring flavonoids is extended by the identification of 3',4',5,7-tetrahydroxy-5'-methoxyflavanone and apigenin-5-O-α-L-rhamnopyranosyl-7-O-ß-D-glucopyranoside obtained from leaf extracts of Markhamia zanzibarica and aromadendrin-7-O-(2″-O-formyl)-ß-D-glucopyranoside isolated from Spathodea campanulata. The latter compound is the first example of a flavonoid possessing a formylated glucosyl moiety.

Different Inhibitory Potencies of Oseltamivir Carboxylate, Zanamivir, and Several Tannins on Bacterial and Viral Neuraminidases as Assessed in a Cell-Free Fluorescence-Based Enzyme Inhibition Assay.

Neuraminidaseis a key enzyme in the life cycle of influenza viruses and is present in some bacterial pathogens. We here assess the inhibitory potency of plant tannins versus clinically used inhibitors on both a viral and a bacterial model neuraminidase by applying the 2'-(4-methylumbelliferyl)-α-d-N-acetylneuraminic acid (MUNANA)-based activity assay. A range of flavan-3-ols, ellagitannins and chemically defined proanthocyanidin fractions was evaluated in comparison to oseltamivir carboxylate and zanamivir for their inhibitory activities against viral influenza A (H1N1) and bacterial Vibrio cholerae neuraminidase (VCNA). Compared to the positive controls, all tested polyphenols displayed a weak inhibition of the viral enzyme but similar or even higher potency on the bacterial neuraminidase. Structure-activity relationship analyses revealed the presence of galloyl groups and the hydroxylation pattern of the flavan skeleton to be crucial for inhibitory activity. The combination of zanamivir and EPs® 7630 (root extract of Pelargonium sidoides) showed synergistic inhibitory effects on the bacterial neuraminidase. Co-crystal structures of VCNA with oseltamivir carboxylate and zanamivir provided insight into bacterial versus viral enzyme-inhibitor interactions. The current data clearly indicate that inhibitor potency strongly depends on the biological origin of the enzyme and that results are not readily transferable. The therapeutic relevance of our findings is briefly discussed.

Trans-Resveratrol Induces Apoptosis through ROS-Triggered Mitochondria-Dependent Pathways in A549 Human Lung Adenocarcinoma Epithelial Cells.

Resveratrol has been shown to be a potential chemopreventive and anticancer agent, inducing apoptosis in a variety of cancer cells. The present study was performed to evaluate the effect of resveratrol on A549 human lung adenocarcinoma epithelial cells. 3-(4,5-Dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide evaluation demonstrated that the exposure of cells to increasing concentrations of resveratrol (0-175 µM) for 24 h resulted in a decrease in cell viability (IC50 85.5 µM). Annexin V/propidium iodide double stain verified apoptosis in A549 cells, while negligible cell cytotoxity (≥ 0.5 %) was observed in all untreated incubations. Using colorimetric assay kits, induction of caspase-3, but not of caspase-8, activity was detected in response to resveratrol (> 130 µM). Confirmatory evidence of this finding was provided by Western blotting, indicating expression of cleaved caspase-3 levels in a concentration-dependent manner with a minimum resveratrol concentration of 65 µM required for activation of this protease, while that of caspase-8 remained unaffected. The apoptotic process was associated with reactive oxygen species production in a concentration-dependent manner, evidenced by microscopic examination and fluorescence-activated cell sorting analysis using the 2',7'-dichlorofluorescein diacetate assay. In the presence of the mitochondrial electron transport chain inhibitor rotenone, reactive oxygen species production and the concomitant apoptotic cell population were significantly reduced. This finding suggested that the resveratrol-induced apoptosis was mediated via a mitochondrial pathway alignment in human A549 cells. Although effective levels were observed at high concentrations, the outcome may well differ under in vivo conditions. Finally, experiments reaffirmed the chemical instability of trans-resveratrol, suggesting the need for protection of the solutions from extended exposure to light.

A chemically defined 2,3-trans procyanidin fraction from willow bark causes redox-sensitive endothelium-dependent relaxation in porcine coronary arteries.

Extracts of the bark of willow species (Salix spp.) are popular herbal remedies to relieve fever and inflammation. The effects are attributed to salicin and structurally related phenolic metabolites, while polyphenols including procyanidins are suggested to contribute to the overall effect of willow bark. This study aimed at investigating the relaxant response to a highly purified and chemically defined 2,3-trans procyanidin fraction in porcine coronary arteries. The procyanidin sample produced a concentration-dependent relaxation in U46619-precontracted tissues. Relaxation was predominantly mediated through the redox-sensitive activation of the endothelial phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway, leading to the subsequent activation of endothelial nitric oxide synthase (eNOS) by phosphorylation, as evidenced by Western blotting using human umbilical vein endothelial cells (HUVECs). That the relaxant response to Salix procyanidins was reactive oxygen species (ROS)-dependent with O2(-) as the key species followed from densitometric analysis using 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA assay) and employment of various ROS inhibitors, respectively. The data also suggested the modification of intracellular Ca(2+) levels and KCa channel functions. In addition, our organ bath studies showed that Salix procyanidins reversed the abrogation of the relaxant response to bradykinin by oxidized low-density lipoproteins (oxLDL) in coronary arteries, suggesting a vasoprotective effect of willow bark against detrimental oxLDL in pathological conditions. Taken together, our findings suggest for the first time that 2,3-trans procyanidins may contribute not only to the beneficial effects of willow bark but also to health-promoting benefits of diverse natural products of plant origin.

2,3-cis-procyanidins elicit endothelium-dependent relaxation in porcine coronary arteries via activation of the PI3/Akt kinase signaling pathway.

Polyphenols including procyanidins have been reported to reduce the risk of cardiovascular diseases. However, polyphenolic extracts represent complex mixtures, and detailed information on their chemical composition is commonly lacking. The aim of this study was to investigate the potential of a highly purified and chemically defined 2,3-cis-procyanidin sample (di- to hexameric [4ß,8]-linked oligomers) from Nelia meyeri to relax coronary arteries and to get insight into the underlying mechanisms. The procyanidins produced a concentration-dependent relaxation in endothelium-intact vascular rings by activation of the NO and endothelium-derived hyperpolarizing factor (EDHF)-signaling pathway via PI3/Akt kinase in a redox-sensitive manner, with O2(-) as key species predominantly produced by xanthine oxidase and NADPH oxidase. Our observations in tissue bath studies were confirmed by Western blotting; 2,3-cis-procyanidins induced phosphorylation of eNOS and Akt in a ROS-dependent manner. These findings provide a basis for comparing the relaxant response and mode of action with that of structurally related proanthocyanidins. Our results may contribute to a better understanding of the potential link between the beneficial effects of proanthocyanidins on vascular health and their broad distribution in many fruits, natural food sources, and foodstuffs.

High sensitivity of Giardia duodenalis to tetrahydrolipstatin (orlistat) in vitro.

Giardiasis, a gastrointestinal disease caused by Giardia duodenalis, is currently treated mainly with nitroimidazoles, primarily metronidazole (MTZ). Treatment failure rates of up to 20 percent reflect the compelling need for alternative treatment options. Here, we investigated whether orlistat, a drug approved to treat obesity, represents a potential therapeutic agent against giardiasis. We compared the growth inhibitory effects of orlistat and MTZ on a long-term in vitro culture adapted G. duodenalis strain, WB-C6, and on a new isolate, 14-03/F7, from a patient refractory to MTZ treatment using a resazurin assay. The giardiacidal concentration of the drugs and their combined in vitro efficacy was determined by median-effect analysis. Morphological changes after treatment were analysed by light and electron microscopy. Orlistat inhibited the in vitro growth of G. duodenalis at low micromolar concentrations, with isolate 14-03/F7 (IC50(24h) = 2.8 µM) being more sensitive than WB-C6 (IC50(24h) = 6.2 µM). The effect was significantly more potent compared to MTZ (IC50(24h) = 4.3 µM and 11.0 µM, respectively) and led to specific undulated morphological alterations on the parasite surface. The giardiacidal concentration of orlistat was >14 µM for 14-03/F7 and >43 µM for WB-C6, respectively. Importantly, the combination of both drugs revealed no interaction on their inhibitory effects. We demonstrate that orlistat is a potent inhibitor of G. duodenalis growth in vitro and kills parasites at concentrations achievable in the gut by approved treatment regimens for obesity. We therefore propose to investigate orlistat in controlled clinical studies as a new drug in giardiasis.

In vitro antileishmanial activity of resveratrol originates from its cytotoxic potential against host cells.

In addition to a range of beneficial pharmacological activities, resveratrol is recently reported to have potential antileishmanial activities in vitro. The present study was conducted to evaluate the effect of resveratrol on promastigotes and amastigotes of transgenic Leishmania major expressing green fluorescent protein in comparison with its direct cytotoxic effects on host cells (bone marrow-derived and J774-G8 macrophages, respectively). As assessed by FACS analysis, resveratrol showed moderate antipromastigote activity at <35 µg/mL (153.2 µM) and promising effects at higher sample concentrations. In contrast, the green fluorescent protein signal as a measure of the intracellular parasites' viability was reduced in a concentration-dependent manner. Resveratrol strongly inhibited NO production, but did not display direct NO-scavenging activity in sodium nitroprusside solution. Western blotting indicated that resveratrol reduced recombinant interferon-γ/LPS-induced expression of iNOS protein. Microscopic studies, MTT evaluation, and FACS analysis showed significant cytotoxic effects on host cells in a concentration-dependent manner. This finding suggests that the in vitro antileishmanial activity of resveratrol is due to cytotoxic effects on host cells rather than attributable to a specific antiparasitic potential.

Structure/antileishmanial activity relationship study of naphthoquinones and dependency of the mode of action on the substitution patterns.

A series of naphthoquinones was tested for activity against both extracellular promastigote and intracellular amastigote Leishmania major GFP in vitro. In parallel, the compounds were evaluated for cytotoxic effects against bone marrow-derived macrophages (BMM Φ) as a mammalian host cell control. Most of the compounds noticeably inhibited the growth of extracellular parasites (IC (50) 0.5 to 6 µM) and the intracellular survival of L. major GFP amastigotes (IC (50) 1 to 7 µM) when compared with the antileishmanial drug amphotericin B (IC (50) of 2.5 and 0.2 µM, respectively). In general, antiprotozoal activity and host cell cytotoxicity seemed to increase in parallel. Conspicuously, the cytotoxic effect was less pronounced on infected host cells when compared with that on noninfected cells. Concerning structure/activity relationships for the tested naphthoquinones, some interesting structural features emerged from this study. Introduction of a methyl or methoxyl group at C-2 of the parent 1,4-naphthoquinone slightly increased the antileishmanial activity against clinically relevant amastigotes, while the presence of a hydroxyl function in this position dramatically reduced the effectiveness. In contrast, hydroxylation at C-5 and dihydroxy substitution at C-5 and C-8 significantly enhanced the antiprotozoal activity. Similarly, the presence of a side chain hydroxyl group PERI to a carbonyl function as represented in the series of shikonin/alkannin derivatives increased the activity when compared with substituted analogs. Within the series of naphthoquinones tested, the dimeric mixture of vaforhizin and isovaforhizin showed the highest activity IN VITRO against the clinically relevant intracellular amastigote with an IC (50) of 1.1 µM. With IC (50) values mostly in the range of 1-3 µM, the shikonin/alkannin derivatives proved to be similarly considerably leishmanicidal. None of the compounds tested was capable to induce NO production known to play a crucial role in the host resistance against intracellular pathogens, excluding activation of microbicidal mechanisms in macrophages. The mode of action apparently depended on the substitution pattern, associated with the electrophilicity of the naphthoquinone or the efficiency of redox cycling. Conspicuously, members oxygenated in the quinone ring proved to be leishmanicidal when coincubated with glutathione, while the majority of the remaining compounds lost activity.

Evaluation of an aqueous-ethanolic extract from Pelargonium sidoides (EPs® 7630) for its activity against group A-streptococci adhesion to human HEp-2 epithelial cells.

AIM OF THE STUDY: The root extract of Pelargonium sidoides DC (Geraniaceae), EPs® 7630, is currently used to treat respiratory tract infections. The therapeutic benefits are largely related to the modulation of the non-specific immune system. The present study was designed to investigate the anti-adhesive activity of this herbal medicine with Streptococcus pyogenes as model microorganism and to identify the underlying biologically active principle. MATERIALS AND METHODS: Adherence of fluorescent-labelled group A-streptococci (GAS) to human epithelial (HEp-2) cells was assessed by flow cytometry. Anti-adhesive properties of the parent extract as well as a methanol-soluble (MSF) and a methanol-insoluble fraction (MIF) derived thereof were examined. Treatment with skin powder produced polyphenol-free samples which were included for comparison. Anti-adherence studies were extended to a series of highly purified proanthocyanidins including homogenous epicatechin- and catechin-based polyflavans, a 'mixed' procyanidin sample, an A-type proanthocyanidin mixture as well as a prodelphinidin test substance. RESULTS: After pre-treatment of GAS with EPs® 7630 or its subfractions MIF and MSF at concentrations of 30 µg/ml, adhesion of the pathogen to HEp-2 cells was inhibited by ca. 45%, ca. 35% and ca. 30%, respectively. However, following preincubation of cells with the extract and the fractions no effect was observed. This finding indicates that the anti-adhesive effects are due to interactions with binding factors on the bacterial surface. Since polyphenol-free samples proved to be inactive, proanthocyanidins appear to represent the anti-adhesive principle. Comparative studies with chemically defined proanthocyanidins revealed that the prodelphinidin nature, i.e. the pyrogallol B-ring elements of constituent flavanyl units, represented an important structural feature of the anti-adhesive potential of this herbal medicine. CONCLUSIONS: The current data provide strong evidence for a potent anti-adhesion principle of the Pelargonium sidoides root extract related to specific proanthocyanidins. This finding suggests an interaction with bacterial binding sites in a specific rather than non-specific manner. However, the blocked adhesion molecules remain to be identified. The anti-adhesive mechanism may well contribute to the anti-infective activity of EPs® 7630 at an early time point of a bacterial infection.

Antimicrobial, Antiviral and Immunomodulatory Activity Studies of Pelargonium sidoides (EPs® 7630) in the Context of Health Promotion.

Pelargonium species contribute significantly to the health care of a large population in the Southern African region, as part of a long-standing medical system intimately linked to traditional healing practices. Most notably, extracts of the roots of P. sidoides have commonly been applied for the treatment of dysentery and diarrhoea but only occasionally for respiratory complaints. Clinical trials have shown that a modern aqueous-ethanolic formulation of P. sidoides extracts (EPs® 7630) is an efficacious treatment for disorders of the respiratory tract, for example bronchitis and sinusitis. It should be noted that EPs® 7630 is the most widely investigated extract and therefore is the focus of this review. In order to provide a rationale for its therapeutic activity extracts have been evaluated for antibacterial activity and for their effects on non-specific immune functions. Only moderate direct antibacterial capabilities against a spectrum of bacteria, including Mycobacteria strains, have been noted. In contrast, a large body of in vitro studies has provided convincing evidence for an anti-infective principle associated with activation of the non-specific immune system. Interestingly, significant inhibition of interaction between bacteria and host cells, a key to the pathogenesis of respiratory tract infections, has emerged from recent studies. In addition, antiviral effects have been demonstrated, including inhibition of the replication of respiratory viruses and the enzymes haemagglutinin and neuraminidase. Besides, an increase of cilliary beat frequency of respiratory cells may contribute to the beneficial effects of P. sidoides extracts. This example provides a compelling argument for continuing the exploration of Nature and traditional medical systems as a source of therapeutically useful herbal medicines.

Anti-infective activities of Pelargonium sidoides (EPS® 7630): effects of induced NO production on Leishmania major in infected macrophages and antiviral effects as assessed in a fibroblast-virus protection assay.

EPs® 7630 is an aqueous-ethanolic extract of the roots of Pelargonium sidoides, employed in the treatment of upper respiratory tract infections. Its anti-infective activity is supposed to be associated with the activation of the nonspecific immune system. Using Leishmania major GFP-infected murine BMMΦ, the NO production of EPs® 7630-activated macrophages was correlated with the reduction of the GFP signal measured at single cell levels using flow cytometry. The anti-infectious effect of EPs® 7630 (3-10 µg/mL) on its own (NO production: 4-13 µM; signal reduction: 25-73 %) was less prominent than that in combination with IFN- γ (100 U/mL) (NO production: 20-27 µM; signal reduction: 35-78 %). Furthermore, supernatants of EPs® 7630-stimulated BMMΦ (10 µg/mL) significantly reduced the cytopathic effect of EMCV on L929 fibroblasts (antiviral activity 80 U/mL) when compared with an IFN- γ standard (100 U/mL). Direct addition of EPs® 7630 to L929 did not mediate cytoprotective effects. The antiviral components induced in BMMΦ by EPs® 7630 remain to be identified. Detection of any IFNs by ELISA was unsuccessful, which may be due to their very low concentrations in cell supernatants. The current data provide convincing support for the induction of anti-infectious responses by EPs® 7630.

Anti-adhesive activities of flavan-3-ols and proanthocyanidins in the interaction of group A-streptococci and human epithelial cells.

Bacterial adhesion to epithelial cells is a key step in infections, allowing subsequent colonization, invasion and internalization of pathogens into tissues. Anti-adhesive agents are therefore potential prophylactic tools against bacterial infections. The range of anti-adhesive compounds is largely confined to carbohydrate analogues. Tannins are generously recognized as potent antimicrobials, but little data exist on their anti-adherence potency. Using a model for mucosal pathogenesis with labeled group A-streptococci (GAS) and human laryngeal HEp-2 cells, a series of flavan-3-ols (epicatechin, epigallocatechin, epigallocatechin-3-O-gallate) and highly purified and chemically characterized proanthocyanidin samples including procyanidins based on epicatechin, catechin or 'mixed' constituent flavanyl units, prodelphinidins made up of (epi)gallocatechin monomeric unts as well as oligomers possessing A-type units in their molecules was evaluated for anti-adhesive effects. Reduced microbial adherence was observed exclusively for prodelphinidins, suggesting that pyrogallol-type elements, i.e., (epi)gallocatechin units are important structural features. This is the first report on structure-activity relationships regarding the anti-adhesive potency of proanthocyanidins. In addition, the structures of the first chemically defined proanthocyanidins from Pelargonium sidoides are disclosed.

Anti-infective mode of action of EPs 7630 at the molecular level.

Clinical trials have shown that EPs 7630, an aqueous ethanolic extract from the roots of Pelargonium sidoides, is an efficacious treatment for respiratory tract infections. A large body of in vitro studies has provided evidence for an anti-infective principle associated with activation of the non-specific immune system. However, the mode of action at the cellular and molecular level is still insufficiently defined. This study, therefore, aimed to provide further insight into the underlying principles of the therapeutic benefits of EPs 7630 under these conditions. Using BMM phi experimentally infected with intracellular bacteria, Listeria monocytogenes, incubation with EPs 7630 (1 - 30 micro increased release of NO, production of membrane bound/intra- and extracellular IL-1, IL-12 and TNF-alpha and changed the expressions of the surface markers CD40 and CD119 at an early time point post infection (6 h) in a concentration-dependent manner in most experiments. Compared with non-infected cells, the effects were more pronounced. LPS + IFN-gamma served as positive and untreated cells as negative controls. Analyses were carried out at single cell levels using flow cytometry, while ELISA was additionally utilized for monitoring secreted cytokines. Although the current data provide additional valuable information for understanding the anti-infective effects of EPs 7630, the triggered signalling pathways associated with host immune responses appear even more complex than anticipated and are evidently not shared by 'classical' immunomodulators to this extent.

Intracellular parasite kill: flow cytometry and NO detection for rapid discrimination between anti-leishmanial activity and macrophage activation.

Transgenic Leishmania expressing fluorescent reporter proteins such as green fluorescent protein (GFP) have opened the way for a flow cytometry (FACS)-based method to assess the killing of Leishmania parasites inside their macrophage host. Compared with counting parasites in microscopic preparations, the assessment of anti-leishmanial effects by FACS analysis promises both strict objectivity and significant reduction of labour-per-sample while scanning thousands of cells within seconds. Compared with other semi-automated methods based on host cell lysis and biochemical quantification of released parasites, the procedure is more direct and simple, reducing handling artefacts. An assay system is described using highly pure murine bone marrow-derived macrophages infected in vitro as a suspension culture with GFP-transfected Leishmania major promastigotes. The cells were rested for 24 h, allowing intracellular promastigotes to transform into amastigotes, and then exposed to macrophage-activating agents (IFN-gamma, LPS) or standard anti-leishmanial therapeutics. Within 48 h, the GFP signal from parasitized macrophages became indiscernible by FACS analysis, both in activated host cells and in cultures treated with the anti-leishmanials. In cultures activated with rIFN-gamma+LPS this coincided with the release of nitric oxides, but this was not the case in cultures treated with anti-leishmanials. Furthermore, by adding propidium iodide immediately before FACS analysis, the effect of treatment on the viability of the host cell was assessed at the same time. The combination of FACS analysis, and PI and NO detection offers a rapid and objective means of testing for intracellular anti-leishmanial effects and general cytotoxicity and gives a first indication of whether the former is due to direct leishmanicidal activity or indirect functions via macrophage activation.

Aqueous ethanolic extract of the roots of Pelargonium sidoides--new scientific evidence for an old anti-infective phytopharmaceutical.

Among the PELARGONIUM-based herbal remedies that are widely used in traditional medical systems in the Southern African region is a highly valued root medicine (commonly termed UMCKALOABO) of initially unknown botanical origin for the treatment of infectious conditions of the respiratory tract including tuberculosis. Nowadays, a modern aqueous-ethanolic formulation of the roots of Pelargonium sidoides (EPs 7630), developed from this traditional medicine, is successfully employed for the treatment of bronchitis. The article summarizes the fascinating story of this herbal medicine including its way to Europe, identification of the botanical origin, and provides background information of the many profound anti-infectious actions and clinical studies. In spite of considerable effort, the underlying chemical principle is still not clear.

Stimulus (polyphenol, IFN-gamma, LPS)-dependent nitric oxide production and antileishmanial effects in RAW 264.7 macrophages.

The effects of interferon (IFN-gamma), lipopolysaccharide (LPS), and some polyphenols as individual stimuli, as well as in various combinations on NO production in non-infected and infected macrophage-like RAW 264.7 cells were investigated, with emphasis on the NO/parasite kill relationship. In non-infected and in Leishmania parasitized cells, gallic acid significantly inhibited the IFN-gamma and LPS-induced NO detected in the supernatant. This effect was less prominent in IFN-gamma- than in LPS-stimulated cells. Interestingly, and in contrast to non-infected cells, gallic acid inhibited NO production only when added within 3h after IFN-gamma+LPS. Addition of gallic acid following prolonged incubation with IFN-gamma+LPS periods (24 h) no longer inhibited, sometimes even enhanced NO release. Notably, an excellent NO/parasite kill relationship was evident from all the experiments. This study was extended to a series of polyphenols (3-O-shikimic acid, its 3,5-digalloylated analogue, catechin, EGCG, and a procyanidin hexamer) with proven immunostimulatory activities. Although these compounds themselves were found to be weak NO-inducers, the viability of intracellular Leishmania parasites was considerably reduced. Furthermore, their dose-dependent effects on macrophage NO release was determined in the presence of IFN-gamma and/or LPS. Again, non-infected and infected cells differed significantly in the NO response, while inhibition of IFN-gamma and/or LPS-induced NO production by the tested polyphenols strongly depended on the given time of exposure and the sequence of immunological stimuli. A strong inverse correlation between NO levels and intracellular survival rates of Leishmania parasites supported the assumption that the observed inhibition of NO was not simply due to interference with the Griess assay used for detection.

An ellagitannin, n-butyl gallate, two aryltetralin lignans, and an unprecedented diterpene ester from Pelargonium reniforme.

The structural diversity of the metabolic pool of Pelargonium reniforme was extended by the characterization of the 1C4-glucose based ellagitannin pelargoniin E, gallic acid n-butyl ester, (-)-4,4',9'-trihydroxy-3',5'-dimethoxy-2,7'-cyclolignan 9-O-beta-glucopyranoside and reniformin, a diterpene ester comprised of a diterpene acid with an uncommon -(CH2)(2)- bridging element linked to 2-(4-hydroxyphenyl)ethansulfonic acid. These metabolites were associated with the known (alpha,beta)-3,4-di-O-galloyl-glucopyranoside, 4,6-dihydroxy-2beta-glucopyranosyloxyacetophenone, 1-O-galloylglycerol, 6'-O-galloylsalidroside and (+)-isolariciresinol-9'-O-beta-glucopyranoside. All structures were established on the basis of spectroscopic methods.

[Pelargonium sidoides-extract (EPs 7630): registration confirms efficacy and safety]. / Pelargonium sidoides-Extrakt (EPs 7630): Zulassung bestätigt Wirksamkeit und Verträglichkeit.

For centuries the roots of Pelargonium sidoides DC have been used in South African ethno-medicine for the treatment of respiratory diseases. In Germany, a medicinal product containing a special extract of this substance is among the group of self-medication products most widely bought at chemist's shops. In December 2005, the Federal Institute for Drugs and Medical Devices (BfArM, Bonn) approved a new license for its use as a drug. The following review focuses on the current pharmacological, toxicological and clinical data covering the efficacy and innocuousness of this drug when administered for the treatment of acute bronchitis.