Toxic inhibition of smooth muscle contractility by plant-derived sesquiterpenes caused by their chemically reactive alpha-methylenebutyrolactone functions

Terpenoids as Human Neutrophil Elastase (HNE) Inhibitors: A Comprehensive Review of Natural Anti-inflammatory Isoprenoids

Human neutrophil elastase (HNE) is an enzyme that plays a key role in the body's inflammatory response. It has been linked to several diseases such as chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. As potential treatments for these diseases, HNE inhibitors are of great interest. Metabolites derived from plants, particularly terpenoids such as β-caryophyllene found in black pepper and other plants, and geraniol present in several essential oils, are recognized as significant sources of inhibitors for HNE. Because of their ability to inhibit HNE, terpenoids are considered promising candidates for developing novel therapies to treat inflammatory conditions such as COPD and emphysema. Furthermore, nature can serve as an excellent designer, and it may offer a safer drug candidate for inhibiting HNE production and activity in the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were searched to get relevant and up-to-date literature on terpenoids as human neutrophil elastase inhibitors. This review focuses on the isolation, chemical diversity, and inhibition of human neutrophil elastase (HNE) of various terpenoids reported from natural sources up to 2022. A total of 251 compounds from various terpenoids classes have been reported. Further, it also provides a summary of HNE inhibitors and includes a thorough discussion on the structure-activity relationship.

The introduction of an invasive weed was not followed by the introduction of ethnobotanical knowledge: a review on the ethnobotany of Centaurea solstitialis L. (Asteraceae)

Invasive plants are known for their impacts to ecosystems and societies, but their potential cultural use tend to be unexplored. One important mechanism of plant invasion is the use of "allelochemicals" or "novel weapons": chemical defenses which are new to their invaded habitats and that confer them competitive advantages. However, these chemicals are precisely what confers them ethnobotanical and medicinal properties. We reviewed the literature assessing the biogeography of the cultural uses of the model invasive plant yellow-starthistle (Centaurea solstitialis L.; Asteraceae), and assessed the extent to which the introduction of a weed native to Eurasia into several non-native world regions was paralleled by the spread of cultural uses from its native range. We found that the species was rich in pharmaceutically active compounds and that the species had been traditionally used for medicinal purposes, as raw material, and as food. However, ethnobotanical uses were reported almost exclusively in its native range, with no uses described for the non-native range, apart from honey production in California, Argentina, and Australia. Our study exemplifies how, when plant introductions are not paralleled synchronously by significant human migrations, cultural adoption can be extremely slow, even within the native range of the species. Invasive species can provide real-time insights into the cultural processes by which humans learn to use plants. This case study highlights how biological invasions and cultural expansions can be subjected to different constraints.

Antiproliferative Effects of Cynaropicrin on Anaplastic Thyroid Cancer Cells

BACKGROUND

The sesquiterpene lactone cynaropicrin, a major constituent of the artichoke leaves extracts, has shown several biologic activities in many preclinical experimental models, including anti-proliferative effects.

OBJECTIVE

Herein we evaluated the effects of cynaropicrin on the growth of three human anaplastic thyroid carcinoma cell lines, investigating the molecular mechanism underlying its action.

METHOD

MTT assay was used to evaluate the viability of CAL-62, 8505C and SW1736 cells, and flow cytometry to analyse cell cycle distribution. Western blot was performed to detect the levels of STAT3 phosphorylation and NFkB activation. Antioxidant effects were analyzed by measuring the reactive oxygen species and malonyldialdehyde dosage was used to check the presence of lipid peroxidation.

RESULTS

Viability of CAL-62, 8505C and SW1736 cells was significantly reduced by cynaropicrin in a dose- and time-dependent way, with an EC50 of about 5 µM observed after 48 h of treatment with the compound. Cellular growth inhibition was accompanied both by an arrest of the cell cycle, mainly in the G2/M phase, and the presence of a significant percentage of necrotic cells. After 48 h of treatment with 10 µM of cynaropicrin, a reduced nuclear expression of NFkB and STAT3 phosphorylation were also revealed. Moreover, we observed an increase in lipid peroxidation, without any significant effect on the reactive oxygen species production.

CONCLUSION

These results demonstrate that cynaropicrin reduces the viability and promotes cytotoxic effects in anaplastic thyroid cancer cells associated with reduced NFkB expression, STAT3 phosphorylation and increased lipid peroxidation. Further characterization of the properties of this natural compound may open the way for using cynaropicrin as an adjuvant in the treatment of thyroid cancer.

Cynaropicrin: A Comprehensive Research Review and Therapeutic Potential As an Anti-Hepatitis C Virus Agent

The different pharmacologic properties of plants-containing cynaropicrin, especially artichokes, have been known for many centuries. More recently, cynaropicrin exhibited a potential activity against all genotypes of hepatitis C virus (HCV). Cynaropicrin has also shown a wide range of other pharmacologic properties such as anti-hyperlipidemic, anti-trypanosomal, anti-malarial, antifeedant, antispasmodic, anti-photoaging, and anti-tumor action, as well as activation of bitter sensory receptors, and anti-inflammatory properties (e.g., associated with the suppression of the key pro-inflammatory NF-κB pathway). These pharmacological effects are very supportive factors to its outstanding activity against HCV. Structurally, cynaropicrin might be considered as a potential drug candidate, since it has no violations for the rule of five and its water-solubility could allow formulation as therapeutic injections. Moreover, cynaropicrin is a small molecule that can be easily synthesized and as the major constituent of the edible plant artichoke, which has a history of safe dietary use. In summary, cynaropicrin is a promising bioactive natural product that, with minor hit-to-lead optimization, might be developed as a drug for HCV.

Protective effects of isohelenin, an inhibitor of nuclear factor κB, in endotoxic shock in rats

Recent in vitro studies have shown that isohelenin, a sesquiterpene lactone, inhibits the NF-κB pathway. This study examines the effect of isoheleninin endotoxic shock induced by administration of Escherichia coli endotoxini n male Wistar rats. A group of rats received isohelenin (2 mg/kg intraperitoneally)15 min before endotoxin. In vehicle-treated rats, administration of endotoxin caused severe hypotension, which was associated with a marked hyporeactivity to norepinephrine and acetylcholine in ex vivo aortas. Elevated levels of plasma nitrate/nitrite, metabolites of nitric oxide (NO), were also found. These inflammatory events were preceded by cytosolic degradation of inhibitor-κBα (IκBα) and activation of nuclear factor-κB (NF-κB) in the lung within 15 min of endotoxin administration. Treatment with isohelenin resulted in hemodynamicimprovement and reduced plasma levels of NO metabolites. Nuclear translocation of NF-κB was inhibited by isohelenin treatment in the lung, whereas degradation of IκBα was unchanged. In a separate set of experiments, treatment with isohelenin significantly improved survival in mice challenged with endotoxin. We conclude that isohelenin exerts beneficial therapeutic effects during endotoxic shock through inhibition of NF-κB.

Parthenolide is the Component of Tanacetum Parthenium that Inhibits Nitroglycerin-Induced Fos Activation: Studies in an Animal Model of Migraine

Tanacetum parthenium (TP) is a member of the Asteracee family long used empirically as a herbal remedy for migraine. So far, however, clinical trials have failed to prove consistently the effectiveness of TP extracts in preventing migraine attacks, probably as a consequence of the uncertainty as regards the active principle. In this study, the biological effects of different TP extracts and purified parthenolide were tested in an animal model of migraine based on the quantification of neuronal activation induced by nitroglycerin. The extract enriched in parthenolide significantly reduced nitroglycerin-induced Fos expression in the nucleus trigeminalis caudalis. Purified parthenolide inhibited nitroglycerin-induced neuronal activation in additional brain nuclei and, significantly, the activity of nuclear factor-κB. These findings strongly suggest that parthenolide is the component responsible for the biological activity of TP as regards its antimigraine effect and provide important information for future controlled clinical trials.

Sesquiterpenoids in subtribe Centaureinae (Cass.) Dumort (tribe Cardueae, Asteraceae): distribution, (13)C NMR spectral data and biological properties

Asteraceae Bercht. & J. Presl is one of the biggest and most economically important plant families. The taxonomy and phylogeny of Asteraceae is rather complex and according to the latest and most reliable taxonomic classification of Panero & Funk, based on the analysis of nine chloroplast regions, the family is divided into 12 subfamilies and 35 tribes. One of the largest tribes of Asteraceae is Cardueae Cass. with four subtribes (Carlininae, Echinopinae, Carduinae and Centaureinae) and more than 2500 species. Susanna & Garcia-Jacas have organized the genera of Centaureinae (about 800 species) into seven informal groups, which recent molecular studies have confirmed: 1. Basal genera; 2. Volutaria group; 3. Rhaponticum group; 4. Serratula group; 5. Carthamus group; 6. Crocodylium group; 7. Centaurea group. This review summarizes reports on sesquiterpenoids from the Centaureinae subtribe of the Asteraceae family, as well as the (13)C NMR spectral data described in the literature. It further reviews studies concerning the biological activities of these metabolites. For this work, literature data on sesquiterpenes from the Centaureinae subtribe were retrieved with the help of the SciFinder database and other similar data banks. All entries from 1958 until the end of 2011 were considered. This review is addressed to scientists working in the metabolomics field such as chemists, botanists, etc., the spectroscopic data reported make this work a good tool for structural elucidation, the biological section gives useful information to those who wish to study the structure activity relationships.

Genetic mapping and characterization of the globe artichoke (+)-germacrene A synthase gene, encoding the first dedicated enzyme for biosynthesis of the bitter sesquiterpene lactone cynaropicrin

Globe artichoke (Cynara cardunculus var. scolymus L., Asteraceae) is a perennial crop traditionally consumed as a vegetable in the Mediterranean countries and rich in nutraceutically and pharmaceutically active compounds, including phenolic and terpenoid compounds. Its bitter taste is caused by its high content of sesquiterpene lactones (STLs), such as cynaropicrin. The biosynthetic pathway responsible for STL biosynthesis in globe artichoke is unknown, but likely proceeds through germacrene A, as has been shown for other Asteraceae species. Here, we investigated the accumulation of cynaropicrin in different tissues of globe artichoke, and compared it to accumulation of phenolic compounds. Cynaropicrin concentration was highest in old leaves. A putative germacrene A synthase (GAS) gene was identified in a set of ~19,000 globe artichoke unigenes. When heterologously expressed in Escherichia coli, the putative globe artichoke GAS converted farnesyl diphosphate (FPP) into (+)-germacrene A. Among various tissues assayed, the level of globe artichoke GAS expression was highest in mature (six week old) leaves. A sequence polymorphism within a mapping population parent allowed the corresponding GAS gene to be positioned on a genetic map. This study reports the isolation, expression and mapping of a key gene involved in STL biosynthesis in C. cardunculus. This is a good basis for further investigation of this pathway.

AN AB INITIO STUDY ON THE STRUCTURE–CYTOTOXICITY RELATIONSHIP OF TERPENOID LACTONES BASED ON THE MICHAEL REACTION BETWEEN THEIR PHARMACOPHORES AND L-CYSTEINE-METHYLESTER-1

The cytotoxic effects of terpenoid lactones are attributed to the alkylation of biological nucleophiles, especially sulfhydryl groups in proteins, by the α,β-unsaturated carbonyl moiety of lactones through Michael reaction. Therefore, the cytotoxicity could be reflected by the reactivity of the pharmacophores. In this work, the Michael reaction between 12 α,β-unsaturated-carbonyl-containing small species, i.e. 10 analogues of the alpha methylene gamma butyrolactone moiety of andrographolide, one cyclopentenone, and one methylene–pentanolide, and L-cysteine-methylester-1 were investigated by ab initio methods to mimic the alkylation of proteins by terpenoid lactones. The trend in the calculated reaction free energies of the small species is qualitatively in accordance with the reported cytotoxicity of corresponding terpenoid lactones.

The effect of dehydroleucodine in adipocyte differentiation

Dehydroleucodine (DhL) is a sesquiterpene lactone of the guaianolide group with gastric cytoprotective activity. Recent studies have also demonstrated that DhL inhibits the proliferation of vascular smooth muscle cells. In this study we examined the effect of DhL in the differentiation of 3T3-L1 preadipocytes. The addition of DhL significantly inhibited the differentiation of 3T3-L1 preadipocytes along with a significant decrease in the accumulation of lipid content by a dramatic downregulation of the expression of adipogenic-specific transcriptional factors PPARγ and C-EBPα. However, phosphorylation of AMPKα, Erk1/2 and Akt1 was not inhibited by DhL treatment. Interestingly, we also found that 11,13-dihydrodehydroleucodine, a derivative of DhL with inactivated α-methylene-γ-lactone function, also inhibited the differentiation of 3T3-L1 preadipocytes. Taken together, these data suggest that DhL has an important inhibitory effect in cellular pathways regulating adipocyte differentiation by modulating the PPARγ expression, which is known to play a pivotal role during adipogenesis.

Evaluation of the anti-ulcerogenic effect of sesquiterpene lactones from Centaurea solstitialis L. ssp. solstitialis by using various in vivo and biochemical techniques

The guaianolide type sesquiterpene lactones chlorojanerin, 13-acetyl solstitialin A and solstitialin A were identified as the anti-ulcerogenic components of the chloroform extract of the aerial parts of Centaurea solstitialis ssp. solstitialis (Asteraceae). In this study, these compounds were investigated by using various in vivo ulcer models in rats and mice. Chlorojanerin was shown to be significantly effective in preventing the induction of lesions by ethanol- (EtOH-) (both oral and subcutaneous administration), indomethacin-, indomethacin plus HCl/EtOH-, N(G)-nitro-l-arginine methyl ester plus EtOH-, N-ethylmaleimide plus EtOH-, water immersion and restraint stress, and serotonin, as well as inhibiting titratable gastric acidity and acid output, and increasing gastric pH, but was ineffective in the prevention of ulcers induced by pyloric ligation, diethyldithiocarbamate, and cysteamine, and had no effect on gastric secretion volume or peptic activity. A mixture of 13-acetyl solstitialin A (95%) and solstitialin A (5%) was found to be significantly effective against EtOH-induced lesions on oral administration but was ineffective when administered subcutaneously. This mixture was also found to be effective in preventing lesions induced by EtOH, indomethacin, indomethacin plus HCl/EtOH, N(G)-nitro-l-arginine methyl ester plus EtOH, N-ethylmaleimide plus EtOH, water immersion and restraint stress, serotonin and cysteamine, as well as inhibiting titratable gastric acidity and titratable acid output, and gastric pH, but was found ineffective against the pyloric ligation-induced and diethyldithiocarbamate-induced ulcerogenesis models, as well as gastric secretion volume and peptic activity. On the other hand, active compounds did not show any toxic effect on acute toxicity (3 days administration) evaluation tests in mice.

11,13-dihydro-dehydroleucodine, a derivative of dehydroleucodine with an inactivated alkylating function conserves the anti-proliferative activity in G2 but does not cause cytotoxicity

Modulation of vascular smooth muscle cell (VSMC) proliferation has critical therapeutic implications for vascular disease. Recently, we demonstrated that the sesquiterpene lactone dehydroleucodine (DhL) inhibited the proliferation of VSMCs in G2 phase. It is known that the alpha,beta-unsaturated carbonyl group of the sesquiterpene lactone has a nonspecific alkylating activity that inhibits a large number of enzymes or factors involved in key biological processes. We analyzed whether the DhL alpha-methylene-gamma-lactone function is directly involved in cell proliferation arrest in G2 and in cell toxicity. To this end, the effects of both DhL and 11,13-dihydro-dehydroleucodine (2H-DhL), a derivative of DhL with inactivated alpha-methylenelactone function, on cultured VSMC viability and proliferation were assessed. We found that both DhL and 2H-DhL inhibited the proliferation of VSMCs in a dose-dependent manner, inducing a transient arrest in G2 phase. DhL, but not 2H-DhL, had a cytotoxic effect at concentrations up to 12 microM, indicating that cell proliferation arrest and cytotoxicity are mediated by different cellular targets. From these results we infer that only 2H-DhL is able to arrest cell proliferation in G2 without affecting cell viability at any concentration.

Antiproliferative Activities of Parthenolide and Golden Feverfew Extract Against Three Human Cancer Cell Lines

The medicinal herb feverfew [Tanacetum parthenium (L.) Schultz-Bip.] has long been used as a folk remedy for the treatment of migraine and arthritis. Parthenolide, a sesquiterpene lactone, is considered to be the primary bioactive compound in feverfew having anti-migraine, anti-tumor, and anti-inflammatory properties. In this study we determined, through in vitro bioassays, the inhibitory activity of parthenolide and golden feverfew extract against two human breast cancer cell lines (Hs605T and MCF-7) and one human cervical cancer cell line (SiHa). Feverfew ethanolic extract inhibited the growth of all three types of cancer cells with a half-effective concentration (EC50) of 1.5 mg/mL against Hs605T, 2.1 mg/mL against MCF-7, and 0.6 mg/mL against SiHa. Among the tested constituents of feverfew (i.e., parthenolide, camphor, luteolin, and apigenin), parthenolide showed the highest inhibitory effect with an EC50 against Hs605T, MCF-7, and SiHa of 2.6 microg/mL, 2.8 microg/mL, and 2.7 microg/mL, respectively. Interactions between parthenolide and flavonoids (apigenin and luteolin) in feverfew extract also were investigated to elucidate possible synergistic or antagonistic effects. The results revealed that apigenin and luteolin might have moderate to weak synergistic effects with parthenolide on the inhibition of cancer cell growth of Hs605T, MCF-7, and SiHa.

Antispasmodic activity of fractions and cynaropicrin from Cynara scolymus on guinea-pig ileum

This study describes the antispasmodic activity of some fractions and cynaropicrin, a sesquiterpene lactone from Cynara scolymus, cultivated in Brazil, against guinea-pig ileum contracted by acetylcholine. The dichloromethane fraction showed the most promising biological effects, with an IC(50) of 0.93 (0.49-1.77) mg/ml. Its main active component, the sesquiterpene lactone cynaropicrin, exhibited potent activity, with IC(50) of 0.065 (0.049-0.086) mg/ml, being about 14-fold more active than dichloromethane fraction and having similar potency to that of papaverine, a well-known antispasmodic agent. The results confirm the popular use of artichoke for the treatment of gastrointestinal disturbances, and encourage new studies on this compound, in order to obtain new antispasmodic agents.

Anti-inflammatory profile of dehydrocostic acid, a novel sesquiterpene acid with a pharmacophoric conjugated diene

Sesquiterpene acids are natural products that, in contrast with the thoroughly studied sesquiterpene lactones, have received little pharmacological attention. A good source of this class of compounds is Inula viscosa (Asteraceae), a plant with documented anti-inflammatory effects. The present paper gives the results of our investigations on the biochemical mechanisms involved in the anti-inflammatory activity of one such compound, dehydrocostic acid. The most salient findings were that in vitro dehydrocostic acid inhibits leukotriene B(4) production (IC(50)=22 microM), elastase activity (IC(50)=43 microM) and bee venom phospholipase A(2) activity (IC(50)=17 microM). Furthermore, this sesquiterpenoid was effective on some models of acute edema induced by PLA(2) and 12-O-tetradecanoylphorbol 13-acetate (TPA) Comparison of these data with that known for ilicic acid firmly suggests that the presence of a semiplanar ring A is essential for an improved inhibitory activity on inflammatory mediators.

Relaxation of uterine and aortic smooth muscle by glaucolides D and E from Vernonia liatroides

Vernonia spp. (Asteraceae) are used in herbolaria in Latin America in menstrual and stomach disorders, suggesting smooth muscle relaxing properties of some of their chemical constituents. For pharmacological support for this belief, sesquiterpene lactones glaucolides D and E were assayed on isolated rat smooth muscle. Glaucolide E proved more potent than glaucolide D to relax high KCl- or noradrenaline-induced contractions in aorta and to relax the high KCl-contraction in uterus. Hirsutinolide-type sesquiterpene lactone also was tested but displayed no effect. Relaxation of smooth muscle by structurally related sesquiterpene lactone parthenolide has been attributed mainly to the alpha-methylene gamma-lactone moiety; because glaucolides D and E lack this functional group, their relaxant properties may rely on other alkylating sites such as C10 of the germacra-1(10),4-diene-4-epoxide skeleton.

Parthenolide, an inhibitor of the nuclear factor-kappaB pathway, ameliorates cardiovascular derangement and outcome in endotoxic shock in rodents

Parthenolide is a sesquiterpene lactone used in folk medicine for its anti-inflammatory activity. Recent in vitro studies have shown that this compound inhibits the nuclear factor (NF)-kappaB pathway. This study examines the effect of parthenolide in endotoxic shock in rodents. Endotoxic shock was induced by administration of Escherichia coli endotoxin in rats. Three groups of rats received parthenolide (0.25, 0.5, or 1 mg/kg) 15 min before endotoxin; another group received parthenolide (1 mg/kg) 3 h after endotoxin. In vehicle-treated rats, administration of endotoxin caused severe hypotension, which was associated with a marked hyporeactivity to norepinephrine in ex vivo thoracic aortas. Immunohistochemistry showed positive staining for nitrotyrosine, poly(ADP-ribose) synthetase (PARS) and apoptosis, whereas Northern blot analysis showed increased mRNA expression of inducible nitric-oxide synthase (iNOS) in thoracic aortas. Elevated levels of plasma nitrate/nitrite were also found. Elevated lung levels of myeloperoxidase activity were indicative of infiltration of neutrophils. These inflammatory events were preceded by cytosolic degradation of inhibitor kappaBalpha (IkappaBalpha) and activation of nuclear NF-kappaB in the lung. In vivo pretreatment and post-treatment with parthenolide improved the hemodynamic profile and reduced plasma nitrate/nitrite and lung neutrophil infiltration in a dose-dependent fashion. Vascular hyporeactivity of ex vivo aortas was ameliorated. Treatment with parthenolide also abolished nitrotyrosine formation, PARS expression, and apoptosis and reduced iNOS mRNA content in thoracic aortas. DNA binding of NF-kappaB was inhibited by parthenolide in the lung, whereas degradation of IkappaBalpha was unchanged. In a separate set of experiments, pretreatment or post-treatment with parthenolide significantly improved survival in mice challenged with endotoxin. We conclude that parthenolide exerts beneficial effects during endotoxic shock through inhibition of NF-kappaB.

Phytochemical inhibition of interleukin-4-activated Stat6 and expression of VCAM-1

Cellular functions induced by cytokine interleukin (IL)-4 and IL-4 signaling through signal transducer and activator of transcription (Stat)6 typify a Th2-type immune response. We investigated the inhibitor effect of the NFkappaB blocker parthenolide in the late-phase, Th2-type immune response. Parthenolide blocked by 90.6 +/- 7.4% the IL-4-induced expression of the endothelial vascular cell adhesion molecule (VCAM)-1, a hallmark of extravasation of very late antigen-4-positive leukocytes. The noncytotoxic concentrations of 10 microM parthenolide left a section of the IL-4 receptor signal transduction intact. Parthenolide did not interfere with the immediate IL-4-induced phosphorylation of endothelial Stat6 on its tyrosine residue Y641 and with tyrosine phosphorylation of the adapter molecule, Jak2-both processes are obligatory for dimerization and nuclear translocation of Stat6. But parthenolide inhibited the Stat6 DNA-binding activity in IL-4-stimulated endothelial cells and inhibited the IL-4-driven activation of a luciferase reporter gene under the control of Stat6-responsive elements (IC(50) 5.11 +/- 0.67 microM). Together, these data suggest an anti-chronic disease profile for the sesquiterpene lactone parthenolide.

Sesquiterpene lactone parthenolide, an inhibitor of IkappaB kinase complex and nuclear factor-kappaB, exerts beneficial effects in myocardial reperfusion injury

Sesquiterpene lactones are extracts of common medicinal Asteracae plants used in folk medicine for their anti-inflammatory activity. Recently, in vitro studies have shown that these compounds may interfere with pro-inflammatory gene regulation. This study examines the effects of parthenolide, a sesquiterpene lactone, in experimental myocardial ischemia and reperfusion. Myocardial injury was induced in rats by 30 min occlusion and 120 min reperfusion of the left coronary artery. Parthenolide (250 or 500 microg/kg) or vehicle (0.05% Tween 80, 1 mL/kg) was administered intraperitoneally 10 min before reperfusion. In vehicle-treated rats, ischemia and reperfusion caused myocardial injury, as evaluated by infarct size, serum levels of creatine phosphokinase and by histological examination. Elevated tissue levels of myeloperoxidase activity were indicative of a significant infiltration of neutrophils. This event paralleled the occurrence of oxidative damage, as evaluated by a marked increase in tissue malondialdehyde levels. These inflammatory events were preceded by activation of the IkappaB kinase complex (IKK) and partial disappearance of inhibitor-kappaBalpha (IkappaBalpha) in the cytosol and translocation of the nuclear factor-kappaB (NF-kappaB) to the nucleus, as early as 15 min after reperfusion. Administration of parthenolide ameliorated myocardial injury, lowered serum creatine phosphokinase activity, and reduced neutrophil infiltration and the subsequent oxidative damage. These beneficial effects were associated with inhibition of IKK activity, enhanced stability of IkappaBalpha, and inhibition of nuclear translocation of NF-kappaB. The results of this study suggest that parthenolide may be beneficial for the treatment of reperfusion-induced myocardial damage by inhibition of the IKK/NF-kappaB pathway.

Effect of the chloroform extract of Tanacetum vulgare and one of its active principles, parthenolide, on experimental gastric ulcer in rats

This study examines the anti-ulcerogenic activity of a chloroform extract of Tanacetum vulgare and purified parthenolide, the major sesquiterpene lactone found in the extract. Gastric ulcers induced by oral administration of absolute ethanol to rats were reduced dose-dependently by oral pretreatment of animals with the chloroform extract (2.5-80 mg kg(-1)) or parthenolide (5-40 mg kg(-1)). When administered 30 min before challenge with the alcohol the protection ranged between 34 and 100% for the extract and 27 and 100% for parthenolide. When the products were administered orally 24 h before treatment with ethanol, 40 mg kg(-1) of the extract and of the lactone reduced the mean ulcer index from 4.8+/-0.3 for control animals to 1.4+/-0.2 and 0.5+/-0.1, respectively. The products also prevented alcohol-induced reduction of the number of sulphydryl groups within the gastric mucosa (50.6+/-2.3 microg (mgprotein)(-1) for normal animals compared with 17.7+/-3.0 microg (mg protein)(-1) for alcohol-treated animals). Administration of the extract (80 mg kg(-1)) or parthenolide (40 mg kg(-1)) 24 h before ethanol treatment restored the numbers of mucosal -SH groups to values near those found for normal animals. These results suggest that the products assayed, in particular parthenolide, might find therapeutic application, although further work is required to establish their profit/risk ratio.

Pharmacological activity of feverfew (Tanacetum parthenium (L.) Schultz-Bip.): assessment by inhibition of human polymorphonuclear leukocyte chemiluminescence in-vitro

The bioactivity of feverfew (Tanacetum parthenium) leaf extracts has been analysed, by use of a human polymorphonuclear leukocyte (PMNL) bioassay, to assess the relative contributions of solvent extraction and parthenolide content to the biological potency of the extract. Extracts prepared in acetone-ethanol (system 1) contained significantly more parthenolide (mean +/- s.d. 1.3 +/- 0.2% dry leaf weight) than extracts in chloroform-PBS (phosphate-buffered saline; system 2; 0.1 +/- 0.04% dry leaf weight) or PBS alone (system 3; 0.5 +/- 0.1% dry leaf weight). Extract bioactivity, measured as inhibition of phorbol 12-myristate 13-acetate-induced, 5-amino-2,3-dihydro-1,4-phthalazinedione (luminol)-enhanced PMNL, chemiluminescence, followed a similar trend. Extracts inhibited phorbol 12-myristate 13-acetate-induced oxidative burst by amounts which, if solely attributable to parthenolide, indicated parthenolide concentrations for the respective solvent systems of 2.2 +/- 0.6%, 0.2 +/- 0.1% and 0.9 +/- 0.1% dry leaf weight. The mean ratio of parthenolide concentration to the parthenolide equivalent/PMNL-bioactivity value, for acetone-ethanol and PBS extracts were both 1:1.7. Parthenolide, although a key determinant of biological activity for T. parthenium leaf extracts based on the PMNL-bioassay, seems not to be the sole pharmacologically-active constituent. The identical and elevated bioactivity-parthenolide ratios for both organic and aqueons-phase leaf extracts suggest that a proportion of the other bioactive compounds have solubilities similar to that of parthenolide.