Virology. 2004 Sep 1;326(2):203-19.

The human immunodeficiency virus (HIV) integrase (IN) must covalently join the viral cDNA into a host chromosome for productive HIV infection. l-Chicoric acid (l-CA) enters cells poorly but is a potent inhibitor of IN in vitro. Using quantitative real-time polymerase chain reaction (PCR), l-CA inhibits integration at concentrations from 500 nM to 10 microM but also inhibits entry at concentrations above 1 microM. Using recombinant HIV IN, steady-state kinetic analyses with l-CA were consistent with a noncompetitive or irreversible mechanism of inhibition. IN, in the presence or absence of l-CA, was successively washed. Inhibition of IN diminished, demonstrating that l-CA was reversibly bound to the protein. These data demonstrate that l-CA is a noncompetitive but reversible inhibitor of IN in vitro and of HIV integration in vivo. Thus, l-CA likely interacts with amino acids other than those which bind substrate.

Biol Pharm Bull. 2004 Jul;27(7):1004-9.

Antioxidant and immuno-enhancing effects of Echinacea purpurea.

Mishima S, Saito K, Maruyama H. Api Co., Ltd. NAGARAGAWA Research Center, Nagara, Gifu, Japan.

We studied the protective effects of Echinacea purpurea against radiation by evaluating changes in the peripheral blood cell count and peripheral blood antioxidant activity. E. purpurea administration had a suppressive effect on radiation-induced leukopenia, especially on lymphocytes and monocytes, and resulted in a faster recovery of blood cell counts. Mouse peripheral blood antioxidant activity was increased by E. purpurea, and a relationship between the suppressive effect on radiation-induced leukopenia and the antioxidant effect was suggested. Furthermore, we reviewed the evidence of augmentation of found in this study humoral immunity. The effects of immune activation by E. purpurea were investigated by measuring total immunoglobulin (IgG, IgM). The radioprotective effects of immune activation by E. purpurea were investigated by measuring T lymphocyte subsets in the peripheral blood of mice following whole-body irradiation. E. purpurea activates macrophages to stimulate IFN-gamma production in association with the secondary activation of T lymphocytes, resulting in a decrease in IgG and IgM production. Cytokines released from macrophages in mouse peripheral blood after E. purpurea administration activated helper T cells to proliferate. In addition, it is reported that activated macrophages in association with the secondary T lymphocyte activation increases IFN-gamma production and stimulates proliferation of cytotoxic T cells and suppressor T cells. We think that CD 4 and CD 8 subsets were more immunologically enhanced by E. purpurea than helper T cells and suppressor T cell these results reflect activation. In addition, we think that these results reflect cell-mediated immune responses.

Medicina (Kaunas). 2004;40(7):657-62.

Clin Infect Dis. 2004 May 15;38(10):1367-71. Epub 2004 Apr 26.

Echinacea purpurea for prevention of experimental rhinovirus colds.

Sperber SJ, Shah LP, Gilbert RD. Department of Internal Medicine, Hackensack University Medical Center, Hackensack, NJ, USA.

A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the ability of Echinacea purpurea to prevent infection with rhinovirus type 39 (RV-39). Forty-eight previously healthy adults received echinacea or placebo, 2.5 mL 3 times per day, for 7 days before and 7 days after intranasal inoculation with RV-39. Symptoms were assessed to evaluate clinical illness. Viral culture and serologic studies were performed to evaluate the presence of rhinovirus infection. A total of 92% of echinacea recipients and 95% of placebo recipients were infected. Colds developed in 58% of echinacea recipients and 82% of placebo recipients (P=.114, by Fisher's exact test). Administration of echinacea before and after exposure to rhinovirus did not decrease the rate of infection; however, because of the small sample size, statistical hypothesis testing had relatively poor power to detect statistically significant differences in the frequency and severity of illness.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Clin Chim Acta. 2004 May;343(1-2):161-6.

BACKGROUND: Echinacea is commonly used in oral dosage as an immune stimulant to increase resistance to viral, bacterial and fungal infections of the upper respiratory tract. It has been suggested that Echinacea is able to stimulate innate immune responses, including those regulated by macrophages and natural killer cells. Indeed, macrophages respond to purified polysaccharide and alkylamide preparations. However, the mechanisms for stimulation of cells responsible for adaptive immunity have not been fully elucidated for other molecules present in Echinacea purpurea preparations. METHODS: Adherent and non-adherent mouse splenocyte populations were incubated in vitro with Echinacea, or with water or alcohol soluble Echinacea extract preparations. Supernatants were collected at 48-h post-incubation, and tested by standard ELISA for presence of secreted cytokines and proinflammatory mediators. RESULTS: Whole splenocyte populations were capable of producing significant amounts IL-6 (1014 pg/ml) in response to Echinacea preparations. The response was primarily contained towards products isolated to the water extract preparation; no IL-6 was produced upon challenge with the alcohol extract. The IL-6 response was produced by the non-adherent cellular population, which made 4912 pg/ml IL-6 when treated with water soluble extract at 1 mg/ml. Likewise, the water soluble extract of Echinacea was able to stimulate non-adherent splenocyte populations to produce TNF-alpha (2082 pg/ml), IL-10 (892 pg/ml) and MIP-1alpha (6486 pg/ml) from non-adherent splenocytes, but only significant concentrations of TNF-alpha and MIP-1alpha mediators were produced from adherent populations at similar dose concentrations. Neither population of splenocytes was capable of stimulating significant production of IFN-gamma, IL-2 or IL-12 to any preparation of Echinacea examined. CONCLUSIONS: The immune stimulatory ability of components contained within E. purpurea extracts offer insight into possible therapeutic potential of this product to regulate non-adherent lymphocytes in immune responses and activation events.

J Pharm Biomed Anal. 2004 Apr 16;35(2):289-301.

The aim of this study was to set up and validate an RP-LC method with DAD-detection to quantify caffeic acid derivatives in various Echinacea spp. Samples were extracted with 80% methanol. The analyses were carried out on a Lichrospher RP-18 column (125 mm x 4 mm i.d., 5 microm), with a mobile phase gradient, which increases the acetonitrile level in a phosphoric acid solution (0.1%). The flow rate was 1.5 ml/min. Detection was set at 330 nm. This method allowed the identification and quantification of caftaric acid, chlorogenic acid, caffeic acid, cynarin, echinacoside and cichoric acid in Echinacea roots and derivatives. The total phenolic content was 10.49 mg/g for E. angustifolia, 17.83 mg/g for E. pallida and 23.23 mg/g for E. purpurea. Among Echinacea commercial herbal medicines, a certain variability in the concentrations of phenolic compounds was observed. The radical scavenging activity of Echinacea methanolic extracts was evaluated in vitro with a spectrophotometric method based on the reduction of an alcoholic 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical solution at 517 nm in the presence of a hydrogen donating antioxidant. As for pure compounds, echinacoside had the highest capacity to quench DPPH* radicals (EC50 = 6.6 microM), while caftaric acid had the lowest (EC50 = 20.5 microM). The average EC50 values for E. purpurea, E. pallida and E. angustifolia were 134, 167 and 231 microg/ml, respectively. The radical scavenging activity of Echinacea root extracts reflected their phenolic composition. The results indicate that Echinacea roots and derivatives are a good source of natural antioxidants and could be used to prevent free-radical-induced deleterious effects.

Arzneimittelforschung. 2004;54(2):114-8.

Arch Pediatr Adolesc Med. 2004 Mar;158(3):217-21.

Effectiveness of an herbal preparation containing echinacea, propolis, and vitamin C in preventing respiratory tract infections in children: a randomized, double-blind, placebo-controlled, multicenter study.

Cohen HA, Varsano I, Kahan E. Pediatric and Adolescent Ambulatory Community Clinic, Petach Tikva, Israel.

OBJECTIVE: To evaluate the effectiveness and safety of a preparation containing echinacea, propolis, and vitamin C in the prevention of respiratory tract infections in children during a 12-week winter period. DESIGN: Randomized, double-blind, placebo-controlled study. SUBJECTS: Four hundred thirty children, aged 1 to 5 years, were randomized to an herbal extract preparation (n = 215) or a placebo elixir (n = 215). INTERVENTION: Administration of an herbal preparation (Chizukit) containing 50 mg/mL of echinacea, 50 mg/mL of propolis, and 10 mg/mL of vitamin C, or placebo (5.0 mL and 7.5 mL twice daily for ages 1 to 3 years and 4 to 5 years, respectively) for 12 weeks. RESULTS: Significant mean +/- SD reductions of illnesses were seen in the Chizukit group in the number of illness episodes, 138 vs 308 (55% reduction); number of episodes per child, 0.9 +/- 1.1 vs 1.8 +/- 1.3 (50% reduction, P<.001); and number of days with fever per child, 2.1 +/- 2.9 vs 5.4 +/- 4.4) (62% reduction, P<.001). The total number of illness days and duration of individual episodes were also significantly lower in the Chizukit group. Adverse drug reactions were rare, mild, and transient. CONCLUSION: A preventive effect of a product containing echinacea, propolis, and vitamin C on the incidence of respiratory tract infections was observed.

Publication Types:

•  Clinical Trial

•  Multicenter Study

•  Randomized Controlled Trial

J Clin Pharm Ther. 2004 Feb;29(1):75-83.

Efficacy of a standardized echinacea preparation (Echinilin) for the treatment of the common cold: a randomized, double-blind, placebo-controlled trial.

Goel V, Lovlin R, Barton R. Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.

BACKGROUND: Recently, echinacea has regained popularity as one of the treatments chosen most commonly by consumers with the expectation that it will reduce the severity and duration of the common cold. However, the results from a limited number of clinical trials for this application have thus far been inconclusive. This incongruity may be the result of investigators utilizing poorly standardized echinacea products, likely devoid of sufficient quantities of active constituents necessary to exert a definitive clinical effect. Therefore, a formulation containing alkamides, cichoric acid, and polysaccharides at concentrations of 0.25, 2.5, and 25 mg/mL, respectively, was prepared from freshly harvested Echinacea purpurea plants (commercially available as Echinilin, Natural Factors Nutritional Products, Inc., Vancouver, BC, Canada). The objective of this study was to test the efficacy of this highly standardized formulation in reducing the severity and duration of symptoms of a naturally acquired common cold. METHODS: In a randomized, double-blind, placebo-controlled trial, 282 subjects aged 18-65 years with a history of two or more colds in the previous year, but otherwise in good health, were recruited. The subjects were randomized to receive either echinacea or placebo. They were instructed to start the echinacea or placebo at the onset of the first symptom related to a cold, consuming 10 doses the first day and four doses per day on subsequent days for 7 days. Severity of symptoms (10-point scale: 0, minimum; 9, maximum) and dosing were recorded daily. A nurse examined the subjects on the mornings of days 3 and 8 of their cold. RESULTS: A total of 128 subjects contracted a common cold (59 echinacea, 69 placebo). The total daily symptom scores were found to be 23.1% lower in the echinacea group than in placebo in those who followed all elements of the study protocol (P<0.01). Throughout the treatment period, the response rate to treatments was greater in the echinacea group. A few adverse event profiles were observed in both groups. CONCLUSIONS: Early intervention with a standardized formulation of echinacea resulted in reduced symptom severity in subjects with naturally acquired upper respiratory tract infection. Further studies with larger patient populations appear to be warranted.

Immunopharmacol Immunotoxicol. 2003 Nov;25(4):551-60.

Enhancement of the humoral immune response by Echinacea purpurea in female Swiss mice.

Freier DO, Wright K, Klein K. Department of Biological Sciences, Mount Holyoke College , South Hadley , Massachusetts , USA .

Various preparations of the plant Echinacea purpurea have been investigated for their potential to enhance immune function, primarily through activation of innate immune responses. Few studies have examined the potential for enhancement of humoral immunity. Using female Swiss mice we administered a volumetric dose of a glycerine extract of E. purpurea by oral gavage, to evaluate effects on the IgM specific antibody forming cell (AFC) response. Four days of treatment following immunization with sheep red blood cells (SRBC) produced a significant enhancement over naive controls at doses of 0.4 and 0.8 mL/kg/day. A few clinical trials and anecdotal reports have suggested that the greatest efficacy for E. purpurea occurs in acute use following onset of illness. A time course study, using the time of SRBC immunization to mimic the onset of illness, examined the effects of 8 and 4 days of E. purpurea treatment at 0.6 mL/kg/day. Only in the 4-day administration, with dosing beginning 1 hour after SRBC immunization, was there an observed enhancement of the antibody forming cell response. This supports the acute use of E. purpurea as suggested by anecdotal reports, and demonstrates the potential for enhancement of humoral immune responses as well as innate immune responses.

J Pharm Biomed Anal. 2003 Nov 24;33(4):845-50.

Trace elements analysis of Echinacea purpurea--herbal medicinal.

Razic S, Onjia A, Potkonjak B. Faculty of Pharmacy, University of Belgrade, Belgrade, Yugoslavia.

Elemental composition of Echinacea purpurea (Asteracae), grown in Serbia under strongly controlled conditions, has been studied. To distinguish elemental patterns of different parts of the plant, the content of Zn, Fe, Cu, Mn, Ca, Mg, Sr, Ni, and Li in root versus upper plant parts were determined, by flame atomic absorption and flame atomic emission spectrometry. Analyses of the mentioned elements in soil and in an ethanolic extract of E. purpurea were made, too. The trace element data were evaluated by multivariate methods, i.e. principal component analysis and hierarchical cluster analysis. This revealed two groups of elements (I: Fe, Cu, Mn, Li; II: Ca, Mg, Zn, Ni), while trace element profiles of root, stem, leaves, and flowers of this plant differed significantly. However, no significant difference in the trace element patterns between the summer and the autumn harvest samples was found.

J Agric Food Chem. 2003 Nov 19;51(24):6922-33.

A reversed-phase high-performance liquid chromatography (HPLC) method has been developed to determine caffeic acid derivatives, for example, cichoric acid, and alkamides in plant parts and herbal products of Echinacea purpurea. The method consists of an extraction procedure whereby the hydrophilic phenolics as well as the lipophilic alkamides are released from the samples, followed by the analytical HPLC procedure for quantitative determination of these compounds. The method is the first one validated for the determination of these two groups of compounds in the same procedure. Naringenin has been used as an internal standard, as no other flavanones are present in the extract and it does not interfere with any of the compounds under investigation. Analysis of Danish-grown plant material shows that it is possible to raise plants of a very high chemical quality in Denmark . A selection of international herbal products available on the Danish market show surprisingly variable quality, not necessarily reflecting the product information given on the labels.

Exp Biol Med ( Maywood ). 2003 Oct;228(9):1051-6.

Regulation of human immune gene expression as influenced by a commercial blended Echinacea product: preliminary studies.

Randolph RK, Gellenbeck K, Stonebrook K. Nutrilite Health Institute, Access Business Group, LLC, Buena Park , California , USA .

Consumption of Echinacea at the first sign of symptoms has been clinically shown to reduce both the severity and duration of cold and flu. Quantitative polymerase chain reaction optimized for precision and reproducibility was utilized to explore in vitro and in vivo changes in the expression of immunomodulatory genes in response to Echinacea. In vitro exposure of THP-1 cells to 250 microg/ml of Echinacea species extracts induced expression (up to 10-fold) of the interleukin-1alpha, interleukin-1beta, tumor necrosis factor-alpha, intracellular adhesion molecule, interleukin-8, and interleukin-10 genes. This preliminary result is consistent with a general immune response and activation of the nonspecific immune response cytokines. In vivo gene expression within peripheral leukocytes was evaluated in six healthy nonsmoking subjects (18-65 years of age). Blood samples were obtained at baseline and on Days 2, 3, 5, and 12 after consuming a commercial blended Echinacea product, three tablets three times daily (1518 mg/day) for two days plus one additional dose (506 mg) on day three. Serum chemistry and hematological values were not different from baseline, suggesting that liver or bone marrow responses were not involved in acute responses to Echinacea. The overall gene expression pattern at 48 hr to 12 days after taking Echinacea was consistent with an antiinflammatory response. The expression of interleukin-1beta, tumor necrosis factor-alpha, intracellular adhesion molecule, and interleukin-8 was modestly decreased up through Day 5, returning to baseline by day 12. The expression of interferon-alpha steadily rose through Day 12, consistent with an antiviral response. These preliminary data present a gene expression response pattern that is consistent with Echinacea's reported ability to reduce both the duration and intensity of cold and flu symptoms.

Publication Types:

•  Clinical Trial

Pol J Vet Sci. 2003;6(3 Suppl):3-5.

Echinacea purpurea stimulates cellular immunity and anti-bacterial defence independently of the strain of mice.

Bany J. Department of Pharmacology and Toxicology, Military Institute of Hygiene and Epidemiology, Warsaw , Poland .

One of the major functions of the immune system is anti-bacterial defence mediated among others by non-specific immunity (macrophages, granulocytes). Echinacea purpurea extracts are widely used in prophylaxis and therapy of various infections, mainly the respiratory tract, in animals and humans. The aim of this work was to evaluate the effect of prophylactic use of Echinacea purpurea extract on the development of Pseudomonas aeruginosa infection in various strains of mice and on some parameters of non-specific and also specific cellular immunity. Mice expressed various, depending on the strain used, susceptibility to infection. Echinacea feeding resulted in diminishing of bacteria number in livers of C57Bl/6 (susceptible strain) as well as B6C3F1 (relative resistant strain) mice. Echinacea feeding of the second relative resistant strain (BALB/c x C3H) F1 resulted in stimulation of granulocytes chemiluminescent and lymphocytes proliferative response.

Medicina ( Kaunas ). 2003;39(8):761-6.

Effect of Echinacea (Echinacea Purpurea L. Moench) preparations on experimental prostate gland.

Skaudickas D, Kondrotas AJ, Baltrusaitis K. Department of Physiology, Kaunas University of Medicine, 3000 Kaunas, Lithuania.

Planta Med. 2003 Jul;69(7):685-6.

Genetic characterization of the three medicinal Echinacea species using RAPD analysis.

Nieri P, Adinolfi B, Morelli I, Breschi MC, Simoni G, Martinotti E.

The three medicinal species of the Echinacea genus, E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench were distinguished using the RAPD (random amplified polymorphic DNA) technique. Species-specific markers were identified from amplicons obtained with four of the twenty 10-mer primers contained in the Operon RAPD kit A. In particular, one marker was identified for E. angustifolia (OPA 20, 1800 pb) and E. pallida (OPA 10, 600 pb) and three markers for E. purpurea (OPA 11 : 1250 pb; OPA 17 : 750, 1800 pb). Genetic distance analysis indicated a high degree of difference among the three species with a relative lower difference between E. angustifolia and E. pallida.

Publication Types:

•  Letter

Parasitol Res. 2003 Sep;91(1):74-8. Epub 2003 Jul 29.

Dietary supplementation with Echinacea and development of immunity to challenge infection with coccidia.

Allen PC. Animal and Natural Resources Institute, Parasite Biology Epidemiology and Systematics Laboratory, USDA-ARS, Beltsville , MD 20705 , USA .

An experiment was conducted to examine the effects of dietary supplementation with 0.1% and 0.5% ground root preparations of Echinacea purpurea (EP; common name: purple cone flower) on the development of immunity following live vaccination and subsequent challenge with multiple coccidia species in an experimental model using a commercial live vaccine preparation. Effects of immunization and EP supplementation on weight gains before challenge, and weight gains, lesion scores and plasma levels of carotenoids and NO2-+NO3- following challenge were determined. In this experiment, combined live vaccination and feed supplementation with 0.1% or 0.5% EP during the first 2 weeks of life provided significant weight gain advantage compared to live vaccination alone. This advantage persisted through 2 weeks of EP withdrawal and subsequent challenge infection. EP supplementation also significantly lowered total lesion scores but did not significantly modify the effects of vaccination and challenge on plasma carotenoids or NO2-+NO3-.

Pharmacol Res. 2003 Sep;48(3):273-7.

Apoptosis, or programmed cell death (PCD), is a physiological active cellular suicide process that occurs in non-contiguous cells, and is usually not associated with inflammation. The apoptotic process can be modulated by various stimuli, including hormones, cytokines, growth factors, and some chemotherapeutic agents. To determine whether Echinacea purpurea and Hypericum perforatum are able to regulate the process of apoptosis in vivo and to define the role of the Fas-Ag and Bcl-2 signal transduction cascade, we have orally treated groups of mice with these vegetable drugs for 14 days. The splenic lymphocytes from mice treated with E. purpurea and H. perforatum at the two dose levels used (30 and 100 mg kg(-1) per day) were shown to be significantly more resistant to apoptosis than those from mice treated only with the vehicle. In addition, mice treated with the natural substances showed a decrease in Fas-Ag expression and an increase in Bcl-2 expression. In conclusion, our results shown that in vivo the studied drugs modulate apoptosis in mice splenic lymphocytes and that this action could be mediated in part by a decrease in Fas-Ag expression and in part by an increase in Bcl-2 expression.

Int Immunopharmacol. 2003 Jul;3(7):1041-8.

Echinacea is one of the most widely used over-the-counter herbal preparations that purport to "improve immune system function", especially when taken as a short course of therapy (6-8 weeks). Since many purchasers are older individuals, a double-blind, placebo-controlled study was performed to investigate whether Echinacea could affect total and differential white cell counts, phagocytic activity and interleukin (IL-2) levels in 12-month-old, healthy, male Sprague-Dawley rats when administered over an 8-week period. Echinacea (50 mg/kg of aerial parts) mixed with peanut butter or peanut butter alone was fed to 16 rats, which were receiving regular food and water ad libitum. Cell counts and immune functions were determined on rat tail vein blood on a weekly basis. Echinacea significantly increased circulating total white cell counts during the first 2 weeks of administration, and IL-2 levels during the final 5 weeks of the study period (p<0.05). Differential counts were altered during the entire 8-week study, with mononuclear cells significantly increased to the detriment of granulocytes (p<0.05). No such changes were observed in animals given peanut butter alone. No difference was observed in phagocytic function between animals given Echinacea or peanut butter alone. These studies suggest that aerial components of Echinacea affect both mononuclear cell levels and circulating IL-2 levels in older animals.

Forsch Komplementarmed Klass Naturheilkd. 2003 Apr;10 Suppl 1:9

[History of a plant: the example of Echinacea]

Hostettmann K. Institut de Pharmacognosie et Phytochimie, Universit de Lausanne , Switzerland .

In comparison with other medicinal plants, the history of use of Echinacea is relatively short. The plant originates from North America and was employed by the indigenous Indians. The first archaeological evidence dates from the 18th century. Included in the name Echinacea or purple coneflower are several species of the Asteraceae family: Echinacea purpurea (L.) Moench, Echinacea angustifolia DC. and Echinacea pallida (Nutt.) Nutt. Information about the use of the plant from traditional healers ranges from external application for wounds, burns and insect bites to the chewing of roots for toothache and throat infections, and internal application for pain, coughs, stomach cramps and snake bites. The interest of white settlers was also drawn to this medicinal plant. The first Echinacea preparation, known as Meyers Blood Purifier, arrived on the market around 1880, with rheumatism, neuralgia and rattlesnake bites as indications. At the beginning of the 20th century, Echinacea was the most frequently used plant preparation in the USA . Commercial cultivation was started in Germany around 1939. The introduction and cultivation of Echinacea in Switzerland by A. Vogel was around 1950. Chemists and pharmacologists became interested in Echinacea and many constituents are now known, such as polysaccharides, echinacoside, cichoric acid, ketoalkenes and alkylamides. The extracts exhibit immunostimulant properties and are mainly used in the prophylaxis and therapy of colds, flu and septic complaints. Although there are over 400 publications concerning the plant and dozens of preparations of Echinacea n the market, the true identity of the active principles still remains open. Copyright 2003 S. Karger GmbH, Freiburg

Publication Types:

•  Historical Article

Schweiz Arch Tierheilkd. 2003 May;145(5):223-31.

Echinacea powder: treatment for canine chronic and seasonal upper respiratory tract infections.

Reichling J. Institut fur Pharmazie und Molekulare Biotechnologie, Ruprecht-Karls-University, Heidelberg , Germany .

An open multi-centered veterinary clinical trial, comparing conditions before and after treatment with a herbal preparation, containing the powdered root of Echinacea purpurea, was conducted by 6 practicing veterinarians in Switzerland . The plant-based immune stimulant was administered to 41 dogs with manifestations of chronic and seasonal upper respiratory tract infections, including pharyngitis/tonsillitis, bronchitis and kennel cough. Each animal was at an individual stage of the disease, with various symptoms and different severity scores, at start of treatment. There was no control group. Echinacea powder (1:3) was administered with the food at a dose of 1.0 g/10 kg body weight once daily for 8 weeks. Overall efficacy showed significant improvement for 92% of 39 dogs after 4 weeks of treatment and this was confirmed after 8 weeks. Significant reductions of severity and resolution of typical clinical symptoms, of clear nasal secretions, enlargement of lymph nodes, dry cough, dyspnea and dry lung sounds, were evident after 4 weeks. Only two adverse effects, not suspected to be attributable to the study drug, were recorded. Because quality and stability of the Echinacea powder were defined, using an analytical standard and purity tests, these data suggest, that the Echinacea preparation can be recommended as a well tolerated alternative treatment of canine upper respiratory tract infections.

Publication Types: Clinical Trial, Multicenter Study

Int Immunopharmacol. 2003 Jun;3(6):811-24.

Echinacea purpurea, a plant originally used by native Americans to treat respiratory infections, has also been shown to exert immunomodulatory activities both in vivo and in vitro. However, the mechanism underlying Echinacea-induced immunomodulation remains largely unknown. This study examined in vitro the effects of soluble extracts of E. purpurea on natural killer (NK) cells present in human peripheral blood mononuclear cells (PBMC). Flow cytometric methods were used to examine activation, cytotoxicity, NK-target binding, and killer cell frequency. Treatment of PBMC with Echinacea overnight resulted in the activation of CD69 expression and increase in mean fluorescence intensity in both the CD16+ and CD16+CD56+ NK subsets. However, the frequency of CD16+ cells was decreased as well as the mean fluorescence intensity was down-regulated. NK cytotoxicity was augmented 100% at the concentration of 0.1 microg/ml of Echinacea in a short time (4-h) assay. Examination at the single cell level revealed augmentation of the frequency of CD56+ NK-target conjugates and a plateau was reached after 30-60 min of incubation. Likewise, the frequency of CD56+ killer cells in the conjugates was also significantly increased by Echinacea. There was recruitment of non-conjugated CD56+ cells into CD16+ NK-target conjugates and activation of the NK-target non-killer conjugates into killer cells. These findings demonstrate that Echinacea extracts are potent activators of NK cytotoxicity. Echinacea augments the frequency of NK target conjugates and activates the programming for lysis of NK cells.

Zhongguo Zhong Yao Za Zhi. 2002 Jun;27(6):418-20.

[Determination of cichoric acid in Echinacea purpuea]

Wang H. School of Pharmaceutical Sciences, Peking University , Beijing 100083, China .

OBJECTIVE: To analyze the natural change rule of active components of E. purpuea by measuring content of cichoric acid. METHOD: Reverse HPLC method was used. RESULT: The maximum cichoric acid content of the roots occured in seedling age of May, and that of the flowers occured in blooming stage of mid July, but cichoric acid in stems was generally low anyway. The maximum content of cichoric acid in the plant above ground occured in the blooming stage of mid July. CONCLUSION: The measuring method of content of cichoric acid is successful and reliable. The optimum stage of harvest in Echinacea purpuea should be guided by natural change rule of cichoric acid content.

Zhongguo Zhong Yao Za Zhi. 2002 Jan;27(1):40-2.

J AOAC Int. 2003 Mar-Apr;86(2):202-8.

Analytical methodologies with ultrasonic extraction and liquid chromatography (LC) were developed for the determination of phenolic compounds in dietary supplements containing Echinacea. The phenolic compounds determined by these methods included caftaric acid, chlorogenic acid, cynarin, echinacoside, and cichoric acid. Samples from tablets, capsules, and bags of tea blends were extracted by sonication for < or = 30 min with methanol-water (60 + 40). The extracts were centrifuged and filtered, and the filtrates were diluted and analyzed by LC using a reversed-phase column and coulometric electrochemical (EC) detection. The mobile phase was acetonitrile-ammonium formate buffer, pH 3.5 (15.3 + 84.7) containing tetrabutyl ammonium hydrogen sulfate as an ion-pairing reagent. Extraction conditions (e.g., composition of the extraction solvent and sonication time) were optimized for different types of samples. Intra- and interday analytical variations were determined, and intraday analyses were performed by 2 independent analysts using 2 different LC systems. Results were generally comparable. The LC method with EC detection showed better sensitivity and selectivity when compared with LC with ultraviolet detection, although results were similar for the 2 methods for major compounds, i.e., caftaric acid, echinacoside, and cichoric acid. The identities of these major compounds found in samples were confirmed by LC/electrospray ionization mass spectrometry.

J Agric Food Chem. 2003 Mar 12;51(6):1608-10.

Root and aerial sections (flower, stem, and leaf) of Echinacea purpurea were dried with hot air at temperatures in the range of 40-70 degrees C, and the concentrations of alkylamides and cichoric acid were determined after drying. Increasing drying temperature decreased from 48 h at 40 degrees C to 9 h at 70 degrees C but resulted in a decreased concentration of cichoric acid in all plant sections with a greater loss from aerial plant parts than from the root. There was, however, no significant difference in the concentration of the alkylamides at any drying temperature. Establishment of operational parameters for the drying of echinacea must therefore be structured around the more labile cichoric acid.

J Chromatogr A. 2003 Jan 31;986(1):73-81.

High-performance liquid chromatography (HPLC) coupled with UV photodiode-array detection and electrospray ionization mass spectrometry was developed for the simultaneous analysis of caffeic acid derivatives and alkamides in the roots and extracts of Echinacea purpurea. Caffeic acid derivatives and alkamides produced very abundant peaks in the total ion current chromatogram during negative and positive cone voltage switching. Cichoric acid and the isomer pair, dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide, were used as a standard for quantification of caffeic acid derivatives and alkamides in E. purpurea. This novel method surpasses previously published ones in product quality control and providing the HPLC chromatographic fingerprints of biological active components in E. purpurea.

Theor Appl Genet. 2002 Aug;105(2-3):369-376. Epub 2002 Jun 19.

The genus Echinacea is comprised of nine species, which are perennial herbs indigenous to North America and which have been traditionally used as medicinal plants for centuries. Three Echinacea species, E. angustifolia, E. purpurea, and E. pallida, are currently being traded internationally in the natural products market. Echinacea products constitute a significant portion of this growing, multi-billion dollar industry. The increasing popularity of Echinacea products has led to the expansion of wildcrafting and commercial cultivation to meet the growing demand for plant material. Echinacea is considered of value as a nonspecific immune stimulant, and claims of its efficacy have been tentatively supported by both laboratory and clinical studies. This study used random amplified polymorphic DNA (RAPD) markers to determine the genetic relationships of the three Echinacea species of commercial interest, to evaluate the level of diversity present within germplasm of each of the three species, and to compare accessions of each species available from different sources. A total of 101 RAPD markers were generated for the 76 individuals of four species included in the analysis. NTSYS-pc was used to evaluate the genetic relationships of the three species and to determine the general level of overall diversity. Analysis of molecular variance (AMOVA) was performed using pruned marker sets corrected for the dominant nature of RAPD markers. AMOVA revealed that most of the variation occurred within accessions of the same species, though some accessions of both E. pallida and E. angustifolia were found to be significantly different from other accessions of the same species.

Yao Xue Xue Bao. 2002 Feb;37(2):121-3.

Am Fam Physician. 2003 Jan 1;67(1):77-80.

Echinacea.

Kligler B. Department of Family Medicine, Albert Einstein College of Medicine, New York , New York , USA .

Echinacea is the name of a genus of native North American plants, commonly known as the purple coneflower. The most widely used herbal product in the United States is a liquid extract made from the root of Echinacea purpurea. Because the active component of the plant has not been identified, commercial echinacea products are not typically standardized to any particular component. The research literature on echinacea is difficult to evaluate because of the heterogeneity of the products used in various studies. The herb has been recommended as a prophylactic treatment for upper respiratory infection and is widely used for this indication. However, based on the current literature, it appears that prophylactic echinacea does not have a significant impact on the frequency, severity, or duration of upper respiratory infection. The data regarding treatment of upper respiratory infection appear to support a modest positive effect. No significant herb-drug interactions with echinacea have been reported; adverse effects reported generally have been uncommon and minor, including abdominal upset, nausea, and dizziness.

Planta Med. 2002 Dec;68(12):1118-24.

Differentiation between the complement modulating effects of an arabinogalactan-protein from Echinacea purpurea and heparin.

Alban S. Institute of Pharmacy, University of Regensburg , Regensburg , Germany .

Due to the important physiological role of the complement system, complement modulation, either inhibition or stimulation, is an interesting target for drug development. Several plant polysaccharides are known to exhibit complement modulating activities. Sometimes these effects are described as complement inhibition, although the basic mechanism is a stimulation of the complement activation. This misinterpretation is due to the observed reduced haemolysis in the widely used haemolytic complement assay, which does not allow to differentiate between complement activators and inhibitors, when it is performed in the classical manner. The aim of the presented study was to demonstrate that by simple modifications of the classical procedure this assay becomes an efficient tool to distinguish between real complement inhibitors and complement activating compounds without performing expensive, molecular mechanistic investigations. As practical examples heparin with proven complement inhibiting activity and AGP, a new arabinogalacatan-protein type II isolated from pressed juice of the aerial parts of Echinacea purpurea, as a potential complement activating compound were included in the study. By means of varying the preincubation time of the test compound with complement, AGP was clearly identified as a stimulator of both the classical and alternative pathway of complement activation. These findings correspond to the results of molecular mechanistic investigations. Selective removal of the arabinose side chains of AGP resulted in considerably reduced activity. Therefore, the three-dimensional structure of the polysaccharide, i. e., a backbone branched by side chains, is supposed to be important for the interactions with the complement system. The complement activating effects of AGP may contribute to the well-established immunostimulating effects of the pressed juice from Echinacea purpurea. Abbreviations. AGP:arabinogalactan-protein AGP-hydr.:hydrolysed arabinogalactan-protein AP-CA:haemolytic complement assay for the alternative pathway CP-CA:haemolytic complement assay for the classical pathway EGTA-VB:veronal buffered saline containing EGTA and Mg 2+HPS:human pooled serum RT:room temperature LPS:lipopolysaccharide RaE:rabbit erythrocytes RT:room temperature ShE(A):(sensitised) sheep erythrocytes VB:veronal buffered saline containing Ca 2+ and Mg 2+

J Pharm Pharmacol. 2002 Oct;54(10):1379-83.

Echinacea purpurea (L.) Moench and Hypericum perforatum (L.) were evaluated for their anti-inflammatory activity against carrageenan-induced paw oedema in mice. Each drug was administered orally to mice at 30 and 100 mg kg(-1), twice daily. Only the higher dose significantly inhibited, time dependently, the formation of oedema, evaluated as area under the curve (echinacea P < 0.01; hypericum P < 0.05). Western blot analysis showed that in-vivo treatment with these extracts could modulate lipopolysaccharide (LPS) and interferon-gamma induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression in peritoneal macrophages. In particular, treatment with 100 mg kg(-1) hypericum inhibited both iNOS and COX-2 expression, whereas treatment with 100 mg kg(-1) echinacea down-regulated only COX-2 expression. The present study suggests that the anti-inflammatory effect of these extracts could be in part related to their modulation of COX-2 expression.

Planta Med. 2002 Oct;68(10):926-9.

Rapid and non-destructive determination of the echinacoside content in Echinacea roots by ATR-IR and NIR spectroscopy.

Schulz H. Federal Centre for Breeding Research on Cultivated Plants, Institute for Plant Analysis, Quedlinburg , Germany .

NIR reflection and ATR-IR spectroscopy methods are developed to determine the echinacoside content in roots of Echinacea angustifolia and Echinacea pallida. Based on the recorded spectra and the HPLC reference data, chemometrical analyses are performed using a partial least squares (PLS) algorithm. Generally, good calibration statistics are obtained for the prediction of the echinacoside content presenting comparatively high coefficients of determination (R(2)) and low root mean standard errors of cross validation (RMSECV). It is demonstrated that optimal predictions are possible when using a dispersive spectrometer covering the spectral range from 1,100 to 2,500 nm. In contrast to the time-consuming HPLC method, the described non-destructive measurements allow us to predict the echinacoside content already after an analysis time of approx. one minute. Both spectroscopic techniques presented in this paper are shown to be useful in agricultural practice as well as in the phytopharmaceutical industry.

Publication Types:

•  Evaluation Studies

Planta Med. 2002 Sep;68(9):780-3.

Extracts of 8 taxa of the genus Echinacea were found to have antiviral activity against Herpes simplex (HSV) virus Type I in vitro when exposed to visible and UV-A light. n-Hexane extracts of roots containing alkenes and amides were more active in general than ethyl acetate extracts containing caffeic acids. The most potent inhibitors of HSV were E. pallida var. sanguinea crude (70 % ethanol) inflorescence extract (MIC = 0.026 mg/mL), cichoric acid (MIC = 0.045 mg/mL) and Echinacea purpurea n-hexane root extract (MIC = 0.12 mg/mL).

Wien Med Wochenschr. 2002;152(15-16):407-11.

[New knowledge regarding the effect and effectiveness of Echinacea purpurea extracts]

Bauer R. Institut fur Pharmakognosie, Karl-Franzens-Universitat, Universitatsplatz 4, Graz .

Preparations made from the pressed juice of the flowering aerial parts of the Purple Coneflower, Echinacea purpurea (L.) Moench represent the most commonly used herbal immunnomodulatory agents. They are frequently administered for the supportive treatment of common viral infections of the upper respiratory tract. New clinical studies are reviewed, which demonstrated that corresponding preparations can diminish the severity and the length of common colds significantly, and that they can also be used efficiently for the treatment of children. New investigations have also shown, that stimulation of makrophages and induction of cytokins are major parts of the mode of action, and that glycoproteins/polysaccharides and alkamides are part of the activity relevant constituents.

Publication Types:

•  Review

•  Review, Tutorial

Chem Res Toxicol. 2002 Sep;15(9):1174-8.

In response to concerns that commercial dietary supplements containing Ginkgo biloba (ginkgo) and Echinacea purpurea, Echinacea angustifolia, or Echinacea pallida (echinacea) might be contaminated with colchicine, a highly selective and sensitive assay was developed for colchicine that is based on high-performance liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method utilizes reversed-phase HPLC separation of compounds in a methanolic extract of the dietary supplement or botanical sample followed by positive ion electrospray ionization with collision-induced dissociation and multiple reaction monitoring of three characteristic fragmentation pathways of the protonated molecule of colchicine, m/z 400 --> 358, 400 --> 326, and 400 --> 310. The minimal detectable concentration of colchicine using this assay was 10 pg on-column, which is equivalent to 20 ppb colchicine in a 0.5 g ginkgo leaf sample. The method was validated by analyzing 0.5 g samples spiked with colchicine and determining the recovery. A total of 26 commercial ginkgo and echinacea dietary supplements were purchased from pharmacies in Chicago , IL , and analyzed for colchicine. In contrast to a recent report, no colchicine was detected in any of the samples. In addition, authenticated ginkgo leaves were collected, assayed, and found to contain no colchicine, which is consistent with the botanical literature. On the basis of the results obtained using this new LC-MS-MS assay, which is more sensitive and more selective than previously published methods for colchicine, we find no cause for concern regarding colchicine contamination of ginkgo or echinacea dietary supplements.

Phytomedicine. 2002 Jul;9(5):390-7.

A phytopharmaceutical containing an extract of Echinacea purpurea and Glycyrrhiza glabra root (Revitonil tablets) was investigated for its suggested immunostimulating potential, using several in vitro tests and the in vivo carbon-clearance model in mice. In the in vitro phagocytosis test with human granulocytes, Revitonil showed a 44-53% stimulating effect at a concentration of 100 microg/ml. Whereas in the chemoluminescence test at a concentration of 1.25 microg/ml, Revitonil tablets exhibited a moderate enhancing effect only, a remarkable stimulating activity (30-50%) was observed in the T-lymphocyte CD69 bioassay at a concentration of 100 microg-1 microg/ml. The highest immunological efficacy could be assigned to Revitonil as revealed by the in vivo carbon-clearance model in mice. With RCt/RCc-values of 2.0, Revitonil exhibited a very high carbon elimination rate at oral administration. Because the Echinacea and Glycyrrhiza monoextracts alone showed lower RCt/RCc-values (1.3-1.7) than Revitonil, a potentiating synergistic effect of the extract mixture in Revitonil can be postulated.

Electrophoresis. 2002 Sep;23(17):3084-92.

Separation of alkamides from Echinacea purpurea extracts by cyclodextrin-modified micellar electrokinetic chromatography.

Gotti R, Fiori J, Hudaib M. Dipartimento di Scienze Farmaceutiche, Universita di Bologna, Bologna, Italy.

Separation of nine important alkyl methylbutyl- and isobutylamides (known as alkamides) obtained from Echinacea purpurea extracts was investigated by using cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). Hydrophobic alkamides interact strongly with the micelles from the most common surfactants used in MEKC and this lead to predominant partition of the analytes into the micellar phase, resulting in poor resolution. The addition of neutral CDs to the alkaline ( 10 mM phosphate buffer pH 8.0) micellar system of sodium dodecyl sulfate (SDS), sodium cholate (SC) and sodium deoxycholate (SDC) was found to improve the separation of the studied alkamides. Among the several combinations surfactant/CD, three different systems showed to be particularly effective: SDS/hydroxypropyl-beta-CD (110 mM/100 mM) and SC/heptakis (2, 3, 6-tri-O-methyl)-beta-CD (200 mM/40 mM) which provided a complete separation of the studied compounds, and SDC/heptakis (2, 6-di-O-methyl)-beta-CD. The importance of appropriate surfactant vs. CD concentration ratio as well as that of total concentration of both surfactant and CD was considered. The optimization of the separation was performed by focussing the need for a rapid separation of nine alkamides diagnostically useful to define the fingerprint of Echinacea species.

J Nutr Biochem. 2002 Aug;13(8):487.

Echinacea plant extract has been used for immunostimulation for many years but the evidence supporting its therapeutic potential is still controversial. Using male Sprague-Dawley rats (425- 475 g ), an in vivo study was conducted to examine the immunomodulatory effects of preparations of Echinacea containing its components cichoric acid, polysaccharides and alkylamides in different concentrations. The rats were gavaged orally with these preparations, two times/day for 4 days. Phagocytic activity of alveolar macrophage was increased with increasing concentrations of the Echinacea components. A trend of increase in TNF-alpha and nitric oxide release by the alveolar macrophages following an in vitro stimulation with LPS was also evident. An enhanced release of cytokines (such as TNF-alpha and IFN-gamma) in response to Echinacea components, was also apparent in rat's spleen macrophage, but at higher concentrations. These results suggest that the Echinacea preparations containing optimal concentrations of cichoric acid, polysaccharides and alkylamides are potentially effective in stimulating an in vivo, non-specific immune response in normal rats.

Equine Vet J. 2002 May;34(3):222-7.

Immunological and haematinic consequences of feeding a standardised Echinacea (Echinacea angustifolia) extract to healthy horses.

O'Neill W. Equine Research Centre, Guelph , Ontario , Canada .

This study was undertaken to compile new data on the efficacy of Echinacea in stimulating the immune system of the horse. Use of Echinacea is becoming widespread in horses, despite an absence of controlled laboratory research into its effectiveness or safety. This paper documents results of a double-blind, placebo-controlled, cross-over trial investigating the effect of standardised Echinacea extract on 8 horses. Animals were supplemented with Echinacea or placebo for 42 days, and their response to supplements recorded. Treatment with Echinacea increased phagocytic ability of isolated neutrophils, boosted peripheral lymphocyte counts and appeared to stimulate neutrophil migration from peripheral circulation into the tissues. Echinacea supplement also increased the size and concentration of peripheral red blood cells, and the concentration of haemoglobin and packed cell volume. It was concluded that Echinacea effectively stimulates equine immunocompetence, and the plant extract behaves, in equine subjects, as a haematinic agent, i.e. one which improves the quality of blood by increasing haemoglobin levels and the number of erythrocytes and which, by virtue of their effects on oxygen transport cells, are considered to improve parameters of exercise physiology and performance.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Planta Med. 2002 Jun;68(6):572-4.

Simultaneous analysis of alkamides and caffeic acid derivatives for the identification of Echinacea purpurea, Echinacea angustifolia, Echinacea pallida and Parthenium integrifolium roots.

Laasonen M, Wennberg T, Harmia-Pulkkinen T, Vuorela H.

A reversed-phase HPLC method was developed using a computer simulation program for the identification of dried roots of Echinacea purpurea, E. angustifolia, E. pallida and Parthenium integrifolium. Hydrophilic and lipophilic compounds were analysed simultaneously leading to a two-fold decrease in analysis time compared to traditional HPLC methods.

Publication Types:

•  Letter

J Agric Food Chem. 2002 Jul 3;50(14):3967-70.

Stabilization of caffeic acid derivatives in Echinacea purpurea L. glycerin extract.

Bergeron C, Gafner S, Batcha LL. Tom's of Maine, Lafayette Center, Kennebunk, Maine, USA.

Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid). Chlorogenic acid, which normally occurs in an ethanol extract of E. purpurea, was not present in the glycerin extract. The caffeic acid derivatives, with the exception of 2-O-feruloyl-tartaric acid, were subject to degradation in the control sample. 2-O-Feruloyl-tartaric acid was stable during the whole testing period. All antioxidant treatments greatly improved the stability of caffeic acid derivatives. Stability was dependent upon the concentration of antioxidant added.

J Agric Food Chem. 2002 Jul 3;50(14):3947-53.

Echinacea has been known for its immunostimulatory activity, and its alkylamide components have been linked to such biological activity. Consequently, alkylamides in Echinacea angustifolia were extracted using supercritical carbon dioxide from fresh and dried roots at 45-60 degrees C and 34-55 MPa, and the alkylamide yield in the extracts was determined. The yield of alkylamides from fresh roots increased with temperature yet decreased with pressure, whereas the yield from air-dried roots (moisture content 8.4%) increased with both temperature and pressure. Freeze-drying of the roots to a moisture content of 4.9% did not result in any further increase in the yield compared to that of air-