Extracts of feverfew inhibit granule secretion in blood platelets and polymorphonuclear leucocytes

Non-Pharmacological Approaches to Headaches: Non-Invasive Neuromodulation, Nutraceuticals, and Behavioral Approaches

Significant side effects or drug interactions can make pharmacological management of headache disorders very difficult. Non-conventional and non-pharmacological treatments are becoming increasingly used to overcome these issues. In particular, non-invasive neuromodulation, nutraceuticals, and behavioral approaches are well tolerated and indicated for specific patient categories such as adolescents and pregnant women. This paper aims to present the main approaches reported in the literature in the management of headache disorders. We therefore reviewed the available literature published between 2010 and 2020 and performed a narrative presentation for each of the three categories (non-invasive neuromodulation, nutraceuticals, and behavioral therapies). Regarding non-invasive neuromodulation, we selected transcranial magnetic stimulation, supraorbital nerve stimulation, transcranial direct current stimulation, non-invasive vagal nerve stimulation, and caloric vestibular stimulation. For nutraceuticals, we selected Feverfew, Butterbur, Riboflavin, Magnesium, and Coenzyme Q10. Finally, for behavioral approaches, we selected biofeedback, cognitive behavioral therapy, relaxation techniques, mindfulness-based therapy, and acceptance and commitment therapy. These approaches are increasingly seen as a valid treatment option in headache management, especially for patients with medication overuse or contraindications to drug treatment. However, further investigations are needed to consider the effectiveness of these approaches also with respect to the long-term effects.

Phytomedicines in the Treatment of Migraine

Migraine is a disabling neurovascular disorder with few targeted, tolerable and effective treatments. Phytomedicines, or plant-based medicinal formulations, hold great promise in the identification of novel therapeutic targets in migraine. Many patients also turn toward herbal and plant-based therapies for the treatment of their migraines as clinical and preclinical evidence of efficacy increases. Patients seek effective and tolerable treatments instead of or in addition to current conventional pharmacologic therapies. We review some phytomedicines potentially useful for migraine treatment-feverfew (Tanacetum parthenium), butterbur (Petasites hybridus), marijuana (Cannabis spp.), Saint John's Wort (Hypericum perforatum) and the Damask rose (Rosa × damascena)-with respect to their mechanisms of action and evidence for treatment of migraine. The evidence for feverfew is mixed; butterbur is effective with potential risks of hepatotoxicity related to preparation; marijuana has not been shown to be effective in migraine treatment, and data are scant; Saint John's Wort shows relevant physiological activity but is a hepatic enzyme inducer and lacks clinical studies for this purpose; the Damask rose when used in topical preparations did not show efficacy in one clinical trial. Other plant preparations have been considered for migraine treatment but most without blinded randomized, placebo-controlled trial evidence.

Bicyclic eremophilane-type petasite sesquiterpenes potentiate peroxisome proliferator-activated receptor γ activator-mediated inhibition of dendritic cells

Dendritic cell (DC) activation induces expression of co-stimulatory surface molecules, as well as migration into secondary lymphoid organs, where they activate naïve T-cells. A family of plant derivatives, eremophilane-type petasite sesquiterpenes, can regulate the immune system through DC targeting due to their anti-inflammatory effects. Peroxisome proliferator–activated receptor gamma (PPARγ) is involved in inhibition of inflammatory responses and induction of DCs to acquire a mucosal phenotype. Since mucosal DCs are central in innate immune responses, we hypothesized that eremophilane-type petasite sesquiterpenes exerted their anti-inflammatory effects by inhibiting DC maturation and activation through PPARγ. This study assessed the bicyclic eremophilane-type petasite sesquiterpene compounds Fukinone and 10βH-8α,12-Epidioxyeremophil-7(11)-en-8β-ol (ZYFDC21 and ZYFDC22) in the maturation and activation of mouse DC. We measured surface expression of co-stimulatory molecules by flow cytometry and cell-free supernatant cytokine production upon lipopolysaccharide stimulation by enzyme-linked immunosorbent assays (ELISAs) in the presence or absence of PPARγ agonists. DCs were generated from C57BL/6 mice bone marrow cells and harvested. Cells were exposed to bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22 in the presence or absence of synthetic PPARγ agonists (GW1929 and TGZ) or the natural PPARγ ligand 15d-PGJ₂, followed by overnight activation with LPS. We observed differences in the upregulation of surface expression of CD86, along with TNF, IL-6, and IL-12p70 released by DCs stimulated with LPS, when using combinations of bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22, and PPARγ agonists, in particular the PPARγ ligand 15d-PGJ₂. Our results indicate that bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22 inhibit maturation and activation of DC, and this activity is augmented upon PPARγ activation.

Feverfew

It is widely recognized that alternative therapies have increased in use, and pharmacists are being asked more often to provide information on these products. Alternative therapy products are classified as “dietary supplements,” according to the Dietary Supplement Health and Education Act of 1994 (DSHEA). In section 3 of DSHEA, a dietary supplement is defined as a product intended to supplement the diet and contains one or more of the following: a vitamin, a mineral, or an herb or other botanical or amino acid. According to section 4, these products are excluded from the regulatory approval of the Food and Drug Administration. It is the goal of this feature to provide a critical and unbiased evaluation of alternative therapy products.

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.

Nutraceuticals in Acute and Prophylactic Treatment of Migraine

OPINION STATEMENT

People who suffer from headaches often prefer nutraceutical treatment over traditional pharmacological approaches, due to fear of possible side effects, drug dependence, or addiction. Since treatment with nutraceuticals does not require a doctor's prescription, many patients rely on their own judgment as to when and which one to take, often without consultation or guidance from their physician. Some physicians could provide information about potential efficacy and side effects of various products, but many are not familiar with the nutraceuticals. Widespread skepticism persists among doctors about the effectiveness of these treatments. This is largely due to the lack of rigorous clinical studies. However, even when incontrovertible scientific evidence exists, many physicians remain distrustful of the evidence. The following review summarizes randomized controlled trials of some of the most commonly used non-pharmacological treatments, including magnesium, coenzyme Q10, riboflavin (vitamin B2), petasites, and feverfew (Table 1).

Feverfew for preventing migraine

BACKGROUND

This review is an update of a previously published review in the Cochrane Database of Systematic Reviews on 'Feverfew for preventing migraine' (2004, Issue 1). Feverfew (Tanacetum parthenium L.) extract is a herbal remedy, which has been used for preventing attacks of migraine.

OBJECTIVES

To systematically review the evidence from double-blind randomised controlled trials (RCTs) assessing the clinical efficacy and safety of feverfew monopreparations versus placebo for preventing migraine.

SEARCH METHODS

For this updated version of the review we searched CENTRAL, MEDLINE, EMBASE and AMED to January 2015. We contacted manufacturers of feverfew and checked the bibliographies of identified articles for further trials.

SELECTION CRITERIA

We included randomised, placebo-controlled, double-blind trials assessing the efficacy of feverfew monopreparations for preventing migraine in patients of any age. We included trials using clinical outcome measures, while we excluded trials focusing exclusively on physiological parameters. There were no restrictions regarding the language of publication.

DATA COLLECTION AND ANALYSIS

We systematically extracted data on patients, interventions, methods, outcome measures, results and adverse events. We assessed risk of bias using the Cochrane 'Risk of bias' tool and evaluated methodological quality using the Oxford Quality Scale developed by Jadad and colleagues. Two review authors (BW and MHP for this update, MHP and EE for the original version) independently selected studies, assessed methodological quality and extracted data. We resolved disagreements concerning evaluation of individual trials through discussion.

MAIN RESULTS

We identified one new study for this update, resulting in six trials (561 patients) meeting the inclusion criteria. Five of the six trials reported on the main outcome, migraine frequency. Although five of the trials were generally of good methodological quality, all studies were either of unclear or high risk of bias with regards to sample size. Pooled analysis of the results was not possible due to the lack of common outcome measures and heterogeneity between studies in terms of participants, interventions and designs.The most recent trial added to this version of the review is rigorous and larger (n = 218), using a stable feverfew extract at a dose determined by a previous dose-finding trial. It reports that feverfew reduced migraine frequency by 1.9 attacks from 4.8 to 2.9 and placebo by 1.3 from to 4.8 to 3.5 per month, resulting in a difference in effect between feverfew and placebo of 0.6 attacks per month. For the secondary outcome measures intensity and duration of migraine attacks, incidence and severity of nausea and vomiting, and global assessment no statistically significant differences were reported. Results of previous trials are not convincing: three trials reporting positive effects of feverfew are all of small sample size (17 to 60 participants), while two rigorous trials (n = 50, 147) did not find significant differences between feverfew and placebo. Only mild and transient adverse events, most commonly gastrointestinal complaints and mouth ulcers, were reported in the included trials.

AUTHORS' CONCLUSIONS

Since the last version of this review, one larger rigorous study has been included, reporting a difference in effect between feverfew and placebo of 0.6 attacks per month. This adds some positive evidence to the mixed and inconclusive findings of the previous review. However, this constitutes low quality evidence, which needs to be confirmed in larger rigorous trials with stable feverfew extracts and clearly defined migraine populations before firm conclusions can be drawn. It appears from the data reviewed that feverfew is not associated with any major safety concerns.

Parthenolide inhibits nociception and neurogenic vasodilatation in the trigeminovascular system by targeting the TRPA1 channel

Although feverfew has been used for centuries to treat pain and headaches and is recommended for migraine treatment, the mechanism for its protective action remains unknown. Migraine is triggered by calcitonin gene-related peptide (CGRP) release from trigeminal neurons. Peptidergic sensory neurons express a series of transient receptor potential (TRP) channels, including the ankyrin 1 (TRPA1) channel. Recent findings have identified agents either inhaled from the environment or produced endogenously that are known to trigger migraine or cluster headache attacks, such as TRPA1 simulants. A major constituent of feverfew, parthenolide, may interact with TRPA1 nucleophilic sites, suggesting that feverfew's antimigraine effect derives from its ability to target TRPA1. We found that parthenolide stimulates recombinant (transfected cells) or natively expressed (rat/mouse trigeminal neurons) TRPA1, where it, however, behaves as a partial agonist. Furthermore, in rodents, after initial stimulation, parthenolide desensitizes the TRPA1 channel and renders peptidergic TRPA1-expressing nerve terminals unresponsive to any stimulus. This effect of parthenolide abrogates nociceptive responses evoked by stimulation of peripheral trigeminal endings. TRPA1 targeting and neuronal desensitization by parthenolide inhibits CGRP release from trigeminal neurons and CGRP-mediated meningeal vasodilatation, evoked by either TRPA1 agonists or other unspecific stimuli. TRPA1 partial agonism, together with desensitization and nociceptor defunctionalization, ultimately resulting in inhibition of CGRP release within the trigeminovascular system, may contribute to the antimigraine effect of parthenolide.

Feverfew (Tanacetum parthenium L.): A systematic review

Feverfew (Tanacetum parthenium L.) (Asteraceae) is a medicinal plant traditionally used for the treatment of fevers, migraine headaches, rheumatoid arthritis, stomach aches, toothaches, insect bites, infertility, and problems with menstruation and labor during childbirth. The feverfew herb has a long history of use in traditional and folk medicine, especially among Greek and early European herbalists. Feverfew has also been used for psoriasis, allergies, asthma, tinnitus, dizziness, nausea, and vomiting. The plant contains a large number of natural products, but the active principles probably include one or more of the sesquiterpene lactones known to be present, including parthenolide. Other potentially active constituents include flavonoid glycosides and pinenes. It has multiple pharmacologic properties, such as anticancer, anti-inflammatory, cardiotonic, antispasmodic, an emmenagogue, and as an enema for worms. In this review, we have explored the various dimensions of the feverfew plant and compiled its vast pharmacologic applications to comprehend and synthesize the subject of its potential image of multipurpose medicinal agent. The plant is widely cultivated to large regions of the world and its importance as a medicinal plant is growing substantially with increasing and stronger reports in support of its multifarious therapeutic uses.

Nutraceuticals and headache: the biological basis

Nutrition must affect the structure and functioning of the brain. Since the brain has very high metabolic activity, what we consume throughout the day is likely to dramatically influence both its structure and moment to moment function. It follows that nutritional approaches to all neurological disorders are being researched and entering medical practice, while nutraceutical use is a mainstay of public habits. This review discusses the biological basis for non-conventional or non-mainstream approaches to the treatment of migraine. This requires at least limited discussion of current migraine pathophysiologic theory. How nutrients and other chemicals and approaches are mechanistically involved within migraine pathways is the focus of this article. The nutraceuticals reviewed in detail are: magnesium, riboflavin, coenzyme Q10, petasites, and feverfew with additional comments on marijuana and oxygen/hyperbaric oxygen. This article reviews the science when known related to the potential genetic susceptibility and sensitivity to these treatments. As we know, the basic science in this field is very preliminary, so whether to combine approaches and presumably mechanisms or use them alone or with or without conventional therapies is far from clear. Nonetheless, as more patients and providers participate in patient-centered approaches to care, knowledge of the science underpinning nutritional, nutraceutical, and complementary approaches to treatment for migraine will certainly benefit this interaction.

Complementary and alternative medicine for pain: an evidence-based review

Pain is one of the most prevalent conditions for which patients seek medical attention. Additionally, the number of patients who utilize complementary and alternative medicine as a treatment of pain either in lieu of, or concurrent with, standard conventional treatments continues to grow. While research into the mechanisms, side effect profiles, and efficacies of these alternative therapies has increased in recent years, much more remains unknown and untested. Herein, we review the literature on complementary and alternative medicine for pain, with particular emphasis on evidence-based assessments pertinent to the most common alternative therapies, including acupuncture, herbal therapy, massage therapy, hypnosis, tai chi, and biofeedback.

Complementary and alternative treatments for childhood headaches

Parents frequently ask health care professionals to provide "natural" migraine care for their children and often use herbs, minerals, vitamins, and supplements to treat their children's migraines, thinking that these over-the-counter alternatives are less toxic than prescription medications. The only randomized controlled trial on any alternative treatment for pediatric migraine is for magnesium, and the results were equivocal. Results of two other uncontrolled trials of magnesium, one for migraine and one for episodic tension-type headache, were positive. There is one positive uncontrolled trial each for coenzyme Q10 and Petasites for prevention of pediatric migraine. There are no trials to indicate the safety or efficacy of riboflavin or feverfew for pediatric headache.

Gitadyl versus ibuprofen in patients with osteoarthritis: a double-blind, randomized, cross-over study of clinical efficacy and effects on platelets and PMNs

OBJECTIVES

The aim of the present study was (a) to examine the effects of Gitadyl (a natural product) on platelet aggregation, chemotaxis and oxidative burst response from polymorphonuclear leucocytes (PMNs) and (b) to compare Gitadyl with ibuprofen regarding pain in patients suffering from osteoarthritis.

METHODS

A total of 8 healthy volunteers were employed to determine the effects of Gitadyl on platelet aggregation. Leucocyte function was tested in vitro. Another group of 35 patients with mild to moderate osteoarthritis were employed in a double-blind crossover trial and treated with Gitadyl 3 tablets daily or ibuprofen 1200 mg daily (Ibumetin) in 2 courses of 3 weeks, respectively.

RESULTS

Gitadyl did not interfere with platelet aggregation, in contrast to that observed during aspirin or ibuprofen therapy. Gitadyl, however, inhibited leucocyte chemotaxis and oxidative burst response from PMNs. Gitadyl and ibuprofen resulted in the same reduction of subjective (pain) symptoms. Gastrointestinal symptoms occurred more frequently in those patients treated with ibuprofen.

CONCLUSION

It is suggested that Gitadyl can be a suitable alternative to NSAIDs for patients with pain from osteoarthritis who are prone to bleeding or who develop gastrointestinal (GI) symptoms from NSAIDs even at low dosage.

Perioperative considerations in the management of the patient taking herbal medicines

The use of herbal products has recently increased dramatically in the United States. Patients are flocking to use these and many other complementary or alternative therapies. Perhaps disillusionment with managed care, loss of the traditional doctor-patient relationship, or simply increased access on store shelves, in the media, and on the Internet have all led to this increased use. As physicians, we are facing a paucity of information regarding the true dangers of these products, and there is virtually no information on how they may affect the perioperative milieu. The following review will discuss the limitations of Food and Drug Administration protection, and will review as well as provide an outline of the potential adverse reactions and side-effects that might affect anesthesia administration. To date, no double-blind, placebo-controlled studies have been carried out that specifically address herbal-anesthetic interactions or outcomes.

Antileishmanial activity of parthenolide, a sesquiterpene lactone isolated from Tanacetum parthenium

The in vitro activity of parthenolide against Leishmania amazonensis was investigated. Parthenolide is a sesquiterpene lactone purified from the hydroalcoholic extract of aerial parts of Tanacetum parthenium. This isolated compound was identified through spectral analyses by UV, infrared, (1)H and (13)C nuclear magnetic resonance imaging, DEPT (distortionless enhancement by polarization transfer), COSY (correlated spectroscopy), HMQC (heteronuclear multiple-quantum coherence), and electron spray ionization-mass spectrometry. Parthenolide showed significant activity against the promastigote form of L. amazonensis, with 50% inhibition of cell growth at a concentration of 0.37 microg/ml. For the intracellular amastigote form, parthenolide reduced by 50% the survival index of parasites in macrophages when it was used at 0.81 microg/ml. The purified compound showed no cytotoxic effects against J774G8 macrophages in culture and did not cause lysis in sheep blood when it was used at higher concentrations that inhibited promastigote forms. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis with gelatin as the substrate showed that the enzymatic activity of the enzyme cysteine protease increased following treatment of the promastigotes with the isolated compound. This finding was correlated with marked morphological changes induced by parthenolide, such as the appearance of structures similar to large lysosomes and intense exocytic activity in the region of the flagellar pocket, as seen by electron microscopy. These results provide new perspectives on the development of novel drugs with leishmanicidal activities obtained from natural products.

Complementary and alternative medicine in cardiovascular disease: a review of biologically based approaches

BACKGROUND

The use of complementary and alternative medical (CAM) practices in the United States is growing rapidly. In this manuscript, we review some of the most commonly used biologically based approaches, including herbs, supplements, and other pharmacological therapies, that are encountered in caring for patients with cardiovascular disease, focusing on potential effects, adverse effects, and treatment interactions.

METHODS

Between November 2002 and April 2003, we searched Medline and the National Center for Complementary and Alternative Medicine (NCCAM) web site and its various references and several complementary medicine text books. The key words used were: "cardiovascular diseases," "coronary disease," "heart failure, congestive," "complementary and alternative medicine," "complementary therapies," "drug interactions," and "plants, medicinal." A keyword search of each individual supplement identified was also performed. Additionally, we relied on expert opinion in the field.

RESULTS

Potentially serious adverse effects and interactions with conventional cardiovascular therapies exist for many herbs and supplements. There are currently scarce mechanistic data and very limited data on the effect of CAM therapies on clinical outcomes.

CONCLUSIONS

Randomized clinical trials with adequate power to detect effects of CAM therapies on clinical outcomes and safety are needed. Until these data are available, clinicians must be aware of the increasing use of CAM approaches by their patients and the potential for interactions with conventional therapies and should focus on treatment with proven, evidence-based strategies.

Feverfew for preventing migraine

BACKGROUND

Feverfew (Tanacetum parthenium L.) extract is a herbal remedy used for preventing attacks of migraine.

OBJECTIVES

To systematically review the evidence from double-blind randomised controlled trials (RCTs) assessing the clinical efficacy and safety of feverfew versus placebo for preventing migraine.

SEARCH STRATEGY

Publications describing (or which might describe) double-blind RCTs of feverfew extract for migraine were sought through the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2003); PREMEDLINE/MEDLINE (1966 to July 2003); EMBASE (1974 to July 2003); the trials register of the Cochrane Pain, Palliative and Supportive care group (July 2003); and AMED (1985 to July 2003). Manufacturers of feverfew were contacted and the bibliographies of identified articles checked for further trials.

SELECTION CRITERIA

Randomised, placebo-controlled, double-blind trials assessing the efficacy of feverfew for preventing migraine were included. Trials using clinical outcome measures were included. Trials focusing exclusively on physiological parameters were excluded. There were no restrictions regarding the language of publication.

DATA COLLECTION AND ANALYSIS

Data on patients, interventions, methods, outcome measures, results and adverse events were extracted systematically. Methodological quality was evaluated using the scoring system developed by Jadad and colleagues. Two reviewers independently selected studies, assessed methodological quality and extracted data. Disagreements concerning evaluation of individual trials were resolved through discussion.

MAIN RESULTS

Five trials (343 patients) met the inclusion criteria. Results from these trials were mixed and did not convincingly establish that feverfew is efficacious for preventing migraine. Only mild and transient adverse events were reported in the included trials.

REVIEWER'S CONCLUSIONS

There is insufficient evidence from randomised, double-blind trials to suggest an effect of feverfew over and above placebo for preventing migraine. It appears from the data reviewed that feverfew presents no major safety problems.

Migraine: preventive treatment

Migraine is a common episodic headache disorder. A comprehensive headache treatment plan includes acute attack treatment to relieve pain and impairment and long-term preventive therapy to reduce attack frequency, severity, and duration. Circumstances that might warrant preventive treatment include: (i) migraine that significantly interferes with the patient's daily routine despite acute treatment; (ii) failure, contraindication to, or troublesome side-effects from acute medications; (iii) overuse of acute medications; (iv) special circumstances, such as hemiplegic migraine; (v) very frequent headaches (more than two a week); or (vi) patient preference. Start the drug at a low dose. Give each treatment an adequate trial. Avoid interfering, overused, and contraindicated drugs. Re-evaluate therapy. Be sure that a woman of childbearing potential is aware of any potential risks. Involve patients in their care to maximize compliance. Consider co-morbidity. Choose a drug based on its proven efficacy, the patient's preferences and headache profile, the drug's side-effects, and the presence or absence of coexisting or co-morbid disease. Drugs that have documented high efficacy and mild to moderate adverse events (AEs) include beta-blockers, amitriptyline, and divalproex. Drugs that have lower documented efficacy and mild to moderate AEs include selective serotonin reuptake inhibitors (SSRIs), calcium channel antagonists, gabapentin, topiramate, riboflavin, and non-steroidal anti-inflammatory drugs.

The sesquiterpene lactone parthenolide inhibits LPS- but not TNF-alpha-induced maturation of human monocyte-derived dendritic cells by inhibition of the p38 mitogen-activated protein kinase pathway

BACKGROUND

Dendritic cells (DCs) are the most potent antigen-presenting cells, and the manipulation of DC maturation provides a strategy for the treatment of allergic and inflammatory diseases.

OBJECTIVE

In this study we examined the effect of the anti-inflammatory sesquiterpene lactone parthenolide (PTL) on DC maturation induced by LPS or TNF-alpha.

METHODS

Human monocyte-derived DCs generated by means of culture with GM-CSF and IL-4 were pretreated with PTL and subsequently stimulated with LPS or TNF-alpha.

RESULTS

PTL inhibited the upregulation of CD80, CD83, CD86, CD40, and MHC class II; the allostimulatory function; the production of TNF-alpha and IL-12; and the downregulation of FITC-labeled dextran uptake in human monocyte-derived DCs stimulated with LPS but not with TNF-alpha. The inhibitory effect of PTL on DC maturation was preceded by inhibition of the phosphorylation of p38 mitogen-activated protein kinase but not the nuclear translocation of NF-kappaB.

CONCLUSION

These results might offer PTL not only as a promising compound for the treatment of LPS-induced disorders, including sepsis or septic shock, by inhibition of excessive DC maturation but also as a tool to further dissect the signaling pathways involved in DC maturation.

Benefits, adverse effects and drug interactions of herbal therapies with cardiovascular effects

Because the use of herbal therapies in the U.S. is escalating, it is essential to be aware of clinical and adverse effects, doses and potential drug-herb interactions. A consumer poll in 1998 indicated that one-third of respondents use botanical remedies, and nearly one in five taking prescription medications also used herbs, high-dose dietary supplements or both. An estimated 15 million adults are at risk for potential adverse interactions involving prescription medications and herbs or vitamin supplements, yet most practicing physicians have little knowledge of herbal remedies or their effects. Herbal products are marketed without the proof of efficacy and safety that the Food and Drug Administration (FDA) requires of drugs. The Dietary Supplement and Health Education Act of 1994 allocates responsibility to manufacturers for ensuring safety and efficacy with no specific requirements to submit documentation. Manufacturers may state a product's physiologic effects but may not make claims for the treatment or cure of specific diseases. Consumers and practitioners have little information about product safety, contraindications, interactions or effectiveness and are reliant on manufacturers to provide accurate labeling. Recently, the growing number of foods with herbs has raised concerns at the FDA, which requires evidence that food additives are safe. Considering that the growing appeal of herbal remedies is likely to continue, physicians, particularly cardiologists, must become familiar with the available cardiovascular information on herbs. This review highlights the existing data on the efficacy, adverse effects and interactions for herbal therapies that impact on the cardiovascular system.

Nuclear factor-kappaB as a molecular target for migraine therapy

Nitric oxide (NO) generated from inducible NO synthase (iNOS) participates in immune and inflammatory responses in many tissues. The NO donor glyceryl trinitrate (GTN) provokes delayed migraine attacks when infused into migraineurs and also causes iNOS expression and delayed inflammation within rodent dura mater. Sodium nitroprusside, an NO donor as well, also increases iNOS expression. Because inflammation and iNOS are potential therapeutic targets, we examined transcriptional regulation of iNOS following GTN infusion and the consequences of its inhibition within dura mater. We show that intravenous GTN increases NO production within macrophages. L-N(6)-(1-iminoethyl)lysine, a selective iNOS inhibitor, attenuates the NO signal, emphasizing the importance of enzymatic activity to delayed NO production. iNOS expression is preceded by significant nuclear factor kappa B (NF-kappaB) activity, as reflected by a reduction in the inhibitory protein-kappa-Balpha (IkappaBalpha) and activation of NF-kappaB after GTN infusion. IkappaBalpha degradation, NF-kappaB activation, and iNOS expression were attenuated by parthenolide (3mg/kg), the active constituent of feverfew, an anti-inflammatory drug used for migraine treatment. These findings suggest that GTN promotes NF-kappaB activity and inflammation with a time course consistent with migraine attacks in susceptible individuals. We conclude, based on results with this animal model, that blockade of NF-kappaB activity provides a novel transcriptional target for the development of anti-migraine drugs.

Feverfew extracts and the sesquiterpene lactone parthenolide inhibit intercellular adhesion molecule-1 expression in human synovial fibroblasts

Previous studies have shown that extracts of the aromatic herb feverfew (Tanacetum parthenium) and one of its bioactive components, parthenolide, have anti-inflammatory properties in vivo and in vitro. We examined both crude feverfew extracts and purified parthenolide for their ability to modulate adhesion molecule expression in human synovial fibroblasts. Pretreatment of synovial fibroblasts with either feverfew extracts or purified parthenolide could inhibit the expression of intercellular adhesion molecule-1 (ICAM-1) induced by the cytokines IL-1 (up to 95% suppression), TNF-alpha (up to 93% suppression), and, less strongly, interferon-gamma (up to 39% suppression). Inhibition of ICAM-1 was dose and time dependent; as little as a 30-min pretreatment with feverfew resulted in inhibition of ICAM-1. The decrease in ICAM-1 expression was accompanied by a decrease in T-cell adhesion to the treated fibroblasts. Other herbal extracts with reported anti-inflammatory effects were similarly tested and did not decrease ICAM-1 expression. The modulation of adhesion molecule expression may be an additional mechanism by which feverfew mediates anti-inflammatory effects.

Herbal Medicine: Is it an Alternative or an Unknown? A Brief Review of Popular Herbals Used by Patients in a Pain and Symptom Management Practice Setting

This article will briefly discuss herbals frequently used by patients in a pain and symptom management practice setting with regard to common indications, potential side effects, and drug interactions, as well as a review of available research on each substance. An overview of the regulatory morass that continues to surround the herbal products industry will be presented. The author will examine possible ethic implications of providing care to patients utilizing alternative therapies. Future developments and studies in the field of herbal therapies will be considered.

Inhibition of platelet aggregation and 5-HT release by extracts of Australian plants used traditionally as headache treatments

To identify potential migraine therapeutics, extracts of eighteen plants were screened to detect plant constituents affecting ADP induced platelet aggregation and [14C]5-hydroxytryptamine (5-HT) release. Extracts of the seven plants exhibiting significant inhibition of platelet function were reanalysed in the presence of polyvinyl pyrrolidone (PVP) to remove polyphenolic tannins that precipitate proteins. Two of these extracts no longer exhibited inhibition of platelet activity after removal of tannins. However, extracts of Crataegus monogyna, Ipomoea pes-caprae, Eremophila freelingii, Eremophila longifolia, and Asteromyrtus symphyocarpa still potently inhibited ADP induced human platelet [14C]5-HT release in vitro, with levels ranging from 62 to 95% inhibition. I. pes-caprae, and C. monogyna also caused significant inhibition of ADP induced platelet aggregation. All of these plants have been previously used as traditional headache treatments, except for C. monogyna which is used primarily for protective effects on the cardiovascular system. Further studies elucidating the compounds that are responsible for these anti-platelet effects are needed to determine their exact mechanism of action.

Feverfew for preventing migraine

BACKGROUND

Feverfew (Tanacetum parthenium L.) is a popular herbal remedy for migraine.

OBJECTIVES

To systematically review the evidence for or against the efficacy of feverfew versus placebo for the prevention of migraine.

SEARCH STRATEGY

Electronic literature searches were performed using the databases CISCOM (Research Council for Complementary Medicine, London, UK), MEDLINE, EMBASE, Biosis and the Cochrane Library (each from its inception to April 1998). Manufacturers were contacted and the bibliographies of identified articles checked for further trials.

SELECTION CRITERIA

Randomised, placebo-controlled, double-blind trials assessing the efficacy of feverfew for preventing migraine were included. No restrictions regarding the language of publication were imposed.

DATA COLLECTION AND ANALYSIS

Data on patients, interventions, methods, outcomes and results were extracted in a pre-defined, standardised manner. Methodological quality was evaluated using the scoring system developed by Jadad and colleagues. Both data extraction and the assessment of methodological quality were performed independently by two reviewers.

MAIN RESULTS

Four trials met the inclusion criteria. The majority of these trials suggested beneficial effects of feverfew compared with placebo. However, the trial with the highest methodological quality, which was also among the largest, found no significant difference between feverfew and placebo.

REVIEWER'S CONCLUSIONS

The efficacy of feverfew for the prevention of migraine has not been established beyond reasonable doubt.

Antimycobacterial evaluation of germacranolides

The minimum inhibitory concentrations (MIC) against Mycobacterium tuberculosis and M. avium of parthenolide, costunolide, 1 (10)-epoxycostunolide and other germacranolide-type sesquiterpene lactones and derivatives were determined by use of a radiorespirometric bioassay. Structure-activity relationship studies with natural and semisynthetic sesquiterpene lactones suggested that the alpha-methylene-gamma-lactone moiety is an essential, but not sufficient, structural requirement for significant in vitro activity against M. tuberculosis and M. avium.

Ethnopharmacology of Mexican asteraceae (Compositae)

Traditional herbal remedies have increased in popularity in Europe and the United States in recent years but have always been important to people living in rural Mexico and to their Mexican American/Chicano descendants in the United States. Mexican American patients will often be ingesting herbal teas at the same time that they are being treated for their ailments with antibiotics or antiinflammatory agents. The plant family Asteraceae (Compositae) has contributed the largest number of plants to this pharmacopoeia; the reasons for the importance of this family include its large number of species in Mexico and its wide array of natural products that are useful in the treatment of the maladies that have afflicted the inhabitants of rural Mexico. These natural products include sesquiterpene lactones, polyacetylenes, alkaloids, monoterpenes, and various phenolics such as flavonoids. In this review, we emphasize the sesquiterpene lactones, a large group of compounds with antiinflammatory properties and the ability to relax smooth muscles and thereby relieve gastrointestinal distress. These compounds also readily form adducts with glutathione or free thiols and can thereby affect the metabolism, activity, and toxicology of a wide array of pharmacological agents.

A survey of traditional medicinal plants from the Callejón de Huaylas, Department of Ancash, Perú

The medicinal uses of local flora from the Callejón de Huaylas, Department of Ancash, northeastern Perú, are reported. This geographical area has an old tradition of herbal healing. A total of 33 species have been documented through interactions with village elders, traditional doctors and herbalists. Of the 33 medicinal plant species surveyed in the Callejón de Huaylas, six have not been previously reported, seven have received only minor phytochemical coverage in the literature, and the medicinal uses of seven other plants have not been corroborated with traditional medicinal reports from around the world. The traditional medicinal uses of six medicinal plants have been corroborated with previously published reports but their biological activities have yet to be confirmed in the laboratory. The medicinal uses of four other plants have been corroborated with previously published reports and their biological activities have been confirmed in the laboratory. The purported medicinal use of three plant species could not be confirmed in the laboratory.

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.

Inhibition of 5-lipoxygenase and cyclo-oxygenase in leukocytes by feverfew. Involvement of sesquiterpene lactones and other components

Leaves or infusions of feverfew, Tanacetum parthenium, have long been used as a folk remedy for fever, arthritis and migraine, and derived products are widely available in U.K. health food shops. Previous reports have suggested interactions with arachidonate metabolism. Crude chloroform extracts of fresh feverfew leaves (rich in sesquiterpene lactones) and of commercially available powdered leaves (lactone-free) produced dose-dependent inhibition of the generation of thromboxane B2 (TXB2) and leukotriene B4 (LTB4) by ionophore- and chemoattractant-stimulated rat peritoneal leukocytes and human polymorphonuclear leukocytes. Approximate IC50 values were in the range 5-50 micrograms/mL, and inhibition of TXB2 and LTB4 occurred in parallel. Isolated lactones (parthenolide, epoxyartemorin) treated with cysteine (to neutralize reactive alpha-methylene butyrolactone functions of the sesquiterpenes). Inhibition of eicosanoid generation appeared to be irreversible but not time-dependent. We conclude that feverfew contains a complex mixture of sesquiterpene lactone and non-sesquiterpene lactone inhibitors of eicosanoid synthesis of high potency, and that these biochemical actions may be relevant to the claimed therapeutic actions of the herb.

Helenalin and 11 alpha,13-dihydrohelenalin, two constituents from Arnica montana L., inhibit human platelet function via thiol-dependent pathways

This study investigates the effect on human platelet function of two sesquiterpene lactones from Arnica montana L., helenalin (H) and 11 alpha,13-dihydrohelenalin (DH). Both compounds inhibited collagen-induced platelet aggregation, thromboxane formation and 5-hydroxytryptamine secretion in a concentration-dependent manner at 3-300 microM. When arachidonic acid was used as stimulus, thromboxane formation remained unaffected despite of inhibition of platelet aggregation. Both H and DH reduced the number of acid-soluble sulfhydryl groups in platelets, by up to 78% at anti-aggregatory concentrations. Moreover, H- and DH-induced platelet inhibition could be prevented by the thiol containing amino acid cysteine. It is concluded that H and DH inhibit platelet function via interaction with platelet sulfhydryl groups, probably associated with reduced phospholipase A2 activity.

Feverfew in rheumatoid arthritis: a double blind, placebo controlled study

Feverfew, reputed by folklore to be effective in arthritis, has in vitro properties that could be beneficial in the control of inflammatory disease. Forty one female patients with symptomatic rheumatoid arthritis received either dried chopped feverfew (70-86 mg) or placebo capsules once daily for six weeks. Allocation was random and not known by patient or observer. Variables assessed included stiffness, pain (visual analogue scale), grip strength, articular index, full blood count, erythrocyte sedimentation rate, urea, creatinine, C reactive protein, complement breakdown products (C3dg), rheumatoid factor titre, immunoglobulins (IgG, IgA, IgM), functional capacity, and patient and observer global opinions. One patient (placebo) withdrew after three days and was not included in the analysis. Treatment and placebo groups (20 patients each) were well matched at entry. No important differences between the clinical or laboratory variables of the groups were observed during the six week period. This study therefore shows no apparent benefit from oral feverfew in rheumatoid arthritis.

Prostaglandin synthetase inhibitors in feverfew

The IC50 values for the in-vitro inhibition of the prostaglandin synthetase (bovine seminal vesicle mitochondrial fraction) mediated PGE2 production from arachidonic acid by parthenolide, michefuscalide and chrysanthenyl acetate were 11.0 +/- 0.44, 12.1 +/- 0.51 and 14.2 +/- 0.58 microM (mean +/- 95% confidence limits), respectively.

Pseudo grey platelet syndrome--grey platelets due to degranulation in blood collected into EDTA

We have studied a woman with a history of mild bruising and bleeding, with a normal platelet count and normal clotting factors, who had platelets that appeared grey when stained and viewed under the microscope. Unlike the grey platelet syndrome, the abnormality was only evident when blood had been collected into EDTA and not when citrate or heparin was used as anticoagulant. This 'pseudo grey platelet syndrome' was associated with platelet dense body and alpha granule secretion with no aggregation and occurred on removal of extracellular Ca2+. We discovered that a plasma factor was responsible which could be an immunoglobulin but which is clearly different from the EDTA-sensitive antibodies which cause platelet aggregation and agglutination. We were not able to demonstrate a relationship between the mild bleeding tendency and the in vitro abnormality.

Effects of an extract of feverfew on endothelial cell integrity and on cAMP in rabbit perfused aorta

Extracts of feverfew inhibit platelet aggregation and secretion of granular contents from platelets and other cells. They also modify the interaction of platelets with collagen substrates: feverfew extracts inhibit both platelet spreading and formation of thrombus-like platelet aggregates on the collagen surface. We have now investigated the effect of an extract of feverfew on the vessel wall using rabbit aortas that were perfused with a physiological salt solution in-situ. Addition of feverfew extract to the perfusion medium protected the endothelial cell monolayer from perfusion-induced injury and led to a reversible increase in the cAMP content of aorta segments. The results indicate that feverfew may have a vasoprotective effect in addition to its effects on platelets.

Effect of feverfew on phagocytosis and killing of Candida guilliermondii by neutrophils

The in vitro effect of the herbal remedy feverfew on neutrophil function was examined. It was shown that addition of feverfew extract inhibited phagocytosis of Candida guilliermondii and its overall killing. However, intracellular killing was not affected, suggesting that the apparent defect in total killing merely reflected the failure of uptake. The implications for the in vivo effects of feverfew are discussed.

An extract of feverfew inhibits interactions of human platelets with collagen substrates

The interaction of platelets with surfaces coated with collagens of type III (C III) or IV (C IV) has been studied by measuring the deposition of 51-Cr-labeled platelets and by scanning electron microscopy (SEM). Experiments were performed using platelet-rich plasma (PRP) and suspensions of gel-filtered platelets (GFP). Platelets were deposited on C III mainly as surface-bound aggregates. In contrast they were deposited on C IV mainly as spread forms of individual cells. Formation of aggregates on C III was more extensive for PRP than for GFP; in contrast platelet spreading on C IV was more extensive for GFP than for PRP. The effects of an extract of the plant feverfew on platelet-collagen interactions were determined. Feverfew extract inhibited the deposition of 51-Cr-labeled platelets on both C III and C IV in a dose-dependent way. Similar concentrations of extract were needed to inhibit the formation of surface-bound aggregates and to inhibit platelet spreading in both PRP and GFP.