Echinacea Species (Echinacea Angustifolia (DC.) Hell., Echinacea Pallida (Nutt.) Nutt., Echinacea Purpurea (L.) Moench): A Review Of Their Chemistry, Pharmacology And Clinical Properties
Barnes J, Anderson LA, Gibbons S, Phillipson JD
J Pharm Pharmacol 2005 Aug;57(8):929-54
University of London, Centre for Pharmacognosy and Phytotherapy, School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
This paper reviews the chemistry, pharmacology and clinical properties of Echinacea species used medicinally.
The Echinacea species Echinacea angustifolia, Echinacea pallida and Echinacea purpurea have a long history of medicinal use for a variety of conditions, particularly infections, and today Echinacea products are among the best-selling herbal preparations in several developed countries.
Modern interest in Echinacea is focused on its ImmunoModulatory effects, particularly in the prevention and treatment of upper respiratory tract infections.
The chemistry of Echinacea species is well documented, and several groups of constituents, including Alkamides and Caffeic Acid derivatives, are considered important for activity.
There are, however, differences in the constituent profile of the three species.
Commercial Echinacea samples and marketed Echinacea products may contain one or more of the three species, and analysis of samples of raw material and products has shown that some do not meet recognized standards for pharmaceutical quality.
Evidence from preclinical studies supports some of the traditional and modern uses for Echinacea, particularly the reputed ImmunoStimulant (or ImmunoModulatory) properties.
Several, but not all, clinical trials of Echinacea preparations have reported effects superior to those of placebo in the prevention and treatment of upper respiratory tract infections.
However, evidence of efficacy is not definitive as studies have included different patient groups and tested various different preparations and dosage regimens of Echinacea.
On the basis of the available limited safety data, Echinacea appears to be well tolerated. However, further investigation and surveillance are required to establish the safety profiles of different Echinacea preparations.
Safety issues include the possibility of allergic reactions, the use of Echinacea by patients with autoimmune diseases and the potential for Echinacea preparations to interact with conventional medicines.
Year-And-A-Half Old, Dried Echinacea Roots Retain Cytokine-Modulating Capabilities In An In Vitro Human Older Adult Model Of Influenza Vaccination
Senchina DS, Wu L, Flinn GN, Konopka del N, McCoy JA, Widrelechner MP, Wurtele ES, Kohut ML
Planta Med 2006 Oct;72(13):1207-15
Iowa State University, ImmunoBiology Program, Ames, IA 50011, USA
Alcohol tinctures prepared from aged Echinacea roots are typically taken for preventing or treating Upper Respiratory infections, as they are purported to stimulate immunity in this context.
The effects of long-term (> 1 year) dry storage on the capabilities of Echinacea spp. roots from mature individuals to modulate Cytokine production are unknown.
Using an older human adult model of influenza vaccination, we collected Peripheral Blood Mononuclear Cells from subjects 6 months post-vaccination.
And, stimulated them in vitro with the two Type A influenza Viruses contained in the trivalent 2004-2005 vaccine with a 50 % alcohol tincture prepared from the roots of one of seven Echinacea species: E. angustifolia, E. pallida, E. paradoxa, E. purpurea, E. sanguinea, E. simulata, and E. tennesseensis.
Before being processed into extracts, all roots had been stored under dry conditions for sixteen months.
Cells were cultured for 48 hours; following incubation, supernatants were collected and assayed for InterLeukin-2, InterLeukin-10, and Interferon-γ production, Cytokines important in the Immune response to Viral infection.
Four species ( E. angustifolia, E. purpurea, E. simulata, E. tennesseensis) augmented IL-10 production, diminished IL-2 production, and had no effect on IFN-γ production.
Echinacea pallida suppressed production of all Cytokines; E. paradoxa and E. sanguinea behaved similarly, although to a lesser extent.
The results from these in vitro bioactivity assays indicate that dried Echinacea roots stored for sixteen months maintain Cytokine-modulating capacities.
Our data support and extend previous research and indicate that tinctures from different Echinacea species have different patterns of Immune modulation.
Further, they indicate that certain species may be efficacious in the Immune Response to Viral infection.
Echinacea Species And Alkamides Inhibit ProstaGlandin E(2) Production In RAW264.7 Mouse Macrophage Cells
LaLone CA, Hammer KD, Wu L, Bae J, Leyva N, Liu Y, Solco AK, Kraus GA, Murphy PA, Wurtele ES, Kim OK, Seo KI, Widrlechner MP, Birt DF
J Agric Food Chem 2007 Sep 5;55(18):7314-22
Iowa State University, The Center for Research on Dietary Botanical Supplements, Ames, Iowa 50011, USA
Inhibition of Prostaglandin E(2) (PGE(2)) production in LipoPoLySaccharide-stimulated RAW264.7 mouse Macrophage Cells was assessed with an enzyme immunoassay following treatments with Echinacea extracts or synthesized Alkamides.
Results indicated that ethanol extracts diluted in media to a concentration of 15 microg/mL from E. angustifolia, E. pallida, E. simulata, and E. sanguinea significantly inhibited PGE2 production.
In further studies, PGE2 production was significantly reduced by all synthesized Alkamides assayed at 50 microM, by Bauer Alkamides 8, 12A analogue, and 14, Chen Alkamide 2, and Chen Alkamide 2 analogue at 25 microM and by Bauer Alkamide 14 at 10 microM.
CytoToxicity did not play a role in the noted reduction of PGE2 production in either the Echinacea extracts or synthesized Alkamides.
High-performance liquid chromatography analysis identified individual Alkamides present at concentrations below 2.8 microM in the extracts from the six Echinacea species (15 microg/mL crude extract).
Because active extracts contained < 2.8 microM of specific Alkamide and the results showed that synthetic Alkamides must have a minimum concentration of 10 microM to inhibit PGE2.
It is likely that Alkamides may contribute toward the Anti-Inflammatory activity of Echinacea in a synergistic or additive manner.
Enhancement Of Innate And Adaptive Immune Functions By Multiple Echinacea Species
Zhai Z, Liu Y, Wu L, Senchina DS, Wurtele ES, Murphy PA, Kohut ML, Cunnick JE
J Med Food 2007 Sep;10(3):423-34
Iowa State University, Department of Animal Science, Ames, IA 50011, USA
Echinacea preparations are commonly used as nonspecific ImmunoModulatory agents.
Alcohol extracts from three widely used Echinacea species, Echinacea angustifolia, Echinacea pallida, and Echinacea purpurea, were investigated for immunomodulating properties.
The three Echinacea species demonstrated a broad difference in concentrations of individual Lipophilic Amides and Hydrophilic Caffeic Acid derivatives.
Mice were gavaged once a day (for 7 days) with one of the Echinacea extracts (130 mg/kg) or vehicle and immunized with sheep red blood cells (sRBC) 4 days prior to collection of Immune Cells for multiple immunological assays.
The three herb extracts induced similar, but differential, changes in the percentage of Immune Cell populations and their biological functions, including increased percentages of CD49+ and CD19+ Lymphocytes in Spleen and Natural Killer Cell cytotoxicity.
AntiBody response to sRBC was significantly increased equally by extracts of all three Echinacea species.
Concanavalin A-stimulated Splenocytes from E. angustifolia- and E. pallida-treated mice demonstrated significantly higher T-Cell proliferation.
In addition, the Echinacea treatment significantly altered the Cytokine production by mitogen-stimulated Splenic Cells.
The three herbal extracts significantly increased Interferon-alpha production, but inhibited the release of Tumor Necrosis Factor-gamma and InterLeukin-1beta (IL-1beta).
Only E. angustifolia- and E. pallida-treated mice demonstrated significantly higher production of IL-4 and increased IL-10 production.
Taken together, these findings demonstrated that Echinacea is a wide-spectrum ImmunoModulator that modulates both Innate and Adaptive Immune Responses.
In particular, E. angustifolia or E. pallida may have more Anti-Inflammatory potential.