INTRODUCTION
Echinacea purpurea is extremely popular in the United States. Echinacea ranked second in sales in mainstream market retail stores in 2004. [5] Echinacea purpurea (the purple coneflower) has been used for hundreds of years as an immune stimulant and general anti viral and bacterial aid. And, it may also have benefits on indigestion. Echinacea extract is popularly formulated by itself into cough drops, or blended with honey lemon balm into a special cough drop formula. This formula gives a rich pleasant taste. One of the popular brand is Ricola.
According to NCCAM, there are nine known species of echinacea, all of which are native to the United States and southern Canada. The most commonly used, Echinacea purpurea may offer the most health benefits. The common names of Echinacea include echinacea, purple coneflower, coneflower, American coneflower. Echinacea purpurea has traditionally been used to treat or prevent colds, flu and other infections. Echinacea may stimulate the immune system to help fight infections. Echinacea purpurea is also thought to benefit people suffered from skin issues, such as acene or boils, and wounds.
RESEARCH FINDINGS ABOUT ECHINACEA'S POTENTIAL HEALTH BENEFITS
Echinacea's health benefits may be highly related to its immunomodulatory effects. Goel and colleagues studied the immunomodulatory effects of preparations of Echinacea containing cichoric acid, polysaccharides and alkylamides at different concentrations on male Sprague-Dawley rats. The Echinacea preparations are effective in stimulating an in vivo, non-specific immune response, such as increased release of cytokines, only when cichoric acid, polysaccharides and alkylamides at certain concentrations. [1A] While, another group reports that Echinacea effectively stimulates immunocompetence, and the Echinacea extract improves the quality of blood by increasing haemoglobin levels and the number of erthrocytes in a study of eight horses. [D1] And recently, a group of researchers from India and Turkey published a review article on their findings on the immunomodulatory properties of various phytochemicals and investigate them in Echinacea species extracts. They concluded that: biological processes (such as positive regulation of cytokine production, response to tumor necrosis factor) and molecular functions (such as cytokine receptor binding, receptor-ligand activity, and cytokine activity) among Echinacea species extracts contributing to immune responses. an association of various metabolic pathways, i.e., pathways in cancer, cytokine-cytokine receptor interaction, NF-kappa B, PI3K-Akt, TNF, MAPK, and NOD-like receptor signaling pathways, with immune responses is indicated. [D2]
Inflammation A study aimed to investigate the effects and mechanisms of echinacea purpurea polysaccharide on ulcerative colitis using a mouse model induced by dextran sulfate sodium (DSS). Dietary supplementation with echinacea purpurea polysaccharide (200 mg/kg) significantly improved colon length, weight loss, and histological damage in DSS-induced colitis mice. Mechanistically, echinacea purpurea polysaccharide appeared to inhibit the TLR4/NF-κB inflammatory pathway and maintain intestinal barrier integrity by enhancing claudin-1, ZO-1, and occludin expression while reducing goblet cell loss. Additionally, 16S rRNA sequencing revealed that echinacea purpurea polysaccharide treatment decreased the abundance of potentially harmful bacteria like Bacteroides, Escherichia-Shigella, and Klebsiella, while increasing beneficial Lactobacillus. Furthermore, non-targeted metabonomic analysis indicated that EPP alters gut metabolism. [D3] In an older study, an extract was obtained from Echinacea purpurea by steam distillation shows anti-inflammatory activities in mice and rats. But, only the high dosage group shows statistically significant inhibition of paw edema formation. [C1]
Common cold, rhinovirus infections Common colds are one of the most frequent acute illnesses and Echinaceae purpureae has shown promising results in the relief of common cold symptoms and shortening the duration for improvement. A clinical trial of 80 adult patients with first signs of a cold has shown that echinacea supplement was effective in alleviating symptoms more rapidly than placebo. The echinacea supplements were well-tolerated in the study. [8] In some other studies, Echinacea also effectively reduced the symptoms and duration of the common cold. [9] Echinacea appeared to be safe without serious side effects were shown up in these studies. [9, 10] However, Yale et al. failed to replicate such beneficial effets using 100 mg of freeze-dried pressed juice from the aerial portion of the echinacea purpurea. [7] Turner RB et al also failed to replicate the findings in experimental rhinovirus infections. [1] In the study, Turner utilized three doses of about 300 milligrams of the dried powdered echinacea root. [2]
The American Botanical Council (ABC), has pointed out that: {1} the extracts used were made in a university laboratory are different to commercial echinacea products. (2), the dosages used in this trial were also too low. According to ABC, various international monographs have acknowledged the generally higher dose used for echinacea root products. The World Health Organization (WHO) monograph for Echinacea root (“Radix Echniaceae”) has a dosage for Echinacea angustifolia root at the equivalence of 3 gm per day of the dried root. [3] This same dosage is also acknowledged in the more recently developed draft monographs on Echinacea from the Canadian Natural Health Products Directorate. [4] This dosage level is about 330% higher than the dosage of the echinacea preparations given in the Turner's trial.
Swine flu A research group in Germany studied the anti-viral activity of a commercial Echinacea purpurea extract. They found that this extract inactivated Human H1N1-type IV, highly pathogenic avian IV (HPAIV) of the H5- and H7-types, as well as swine origin IV (S-OIV, H1N1) at concentrations ranging from the recommended dose for oral consumption to several orders of magnitude lower. They reported a direct contact between Echinacea purpurea extract and virus was required, prior to infection, in order to obtain maximum inhibition in virus replication. The extract interfered with the viral entry into cells. In addition, Tamiflu-resistant virus was just as susceptible to Echinacea purpurea extract as the wild type virus. [11]
ECHINACEA SIDE EFFECTS
When taken by mouth with low doses, echinacea usually does not cause any side effects for most people. However, some people experience allergic reactions, including rashes, increased asthma, and anaphylaxis.Gastrointestinal side effects were most common in clinical studies. Further, echinacea may offer more side effects to certain types of users. People are more likely to experience allergic reactions from echinacea if they are allergic to plants in daisy family, such as ragweed, chrysanthemums, marigolds, and daisies. Echinacea may offer more side effects to users suffered from asthma or atopy. [NCCAM] Anyway, there is a report that intake of echinacea supplements is linked to increased amounts of certain bacteria. such as Bacteroides fragilis in the gastrointestinal tract. The increase in amount of Bacteroides fragilis may contribute to inflammatory bowel disease and diarrhea. [X1]
REFERENCE
1. Turner RB, Bauer R, Woelkart K, Hulsey TC, Gangemi DJ. An evaluation of Echinacea angustifolia preparations in experimental rhinovirus infections. N Engl J Med 2005;353:341-348. 2. Blumenthal M, Busse WR, Goldberg A, Hall T, Riggins CW, Rister RS, eds. Klein S, Rister RS, trans. The Complete German Commission E Monographs – Therapeutic Guide to Herbal Medicines. Boston: Integrative Medicine Communications; Austin, TX: American Botanical Council, 1998. 3. Echinacea Radix. In: WHO monographs on selected medicinal plants. Geneva: World Health Organization, 1999. 4. Ehinacea. Natural Health Products Directorate. Health Canada. Draft Jan 2004. 5. Blumenthal M. Herb sales down 7.4 percent in mainstream market. HerbalGram 2005;66:63. 6. Echinacea. In: Blumenthal M, Hall T, Goldberg A, Kunz T, Dinda K, Brinckmann J, et al, eds. The ABC Clinical Guide to Herbs. Austin, TX: American Botanical Council, 2003. [7] Echinacea purpurea therapy for the treatment of the common cold: a randomized, double-blind, placebo-controlled clinical trial. Yale et al, Marshfield Clinic, USA. Arch Intern Med. 2004 Jun 14; 164(11):1237-41. [8] Schulten B et al, Efficacy of Euchinacea purpurea in patients with a common cold. A placebo-controlled, randomised, double-blind clinical trial. Arzneimittelforschung. 2001;51(7):563-8. [9] Lindenmuth GF et al, The efficacy of echinacea compound herbal tea preparation on the severity and duration of upper respiratory and flu symptoms: a randomized, double-blind placebo-controlled study. J Altern Complement Med. 2000 Aug;6(4):327-34. [10] Giles JT et al, Evaluation of echinacea for tratment of the common cold, Pharmacotherapy; 2000 Jun;20(6):690-7. Herbal Science Group Says Dosage Too Low in New Echinacea Trial, citizens. org Aug 9, 2005 [NCCAM] NCCAM Publication No D271 July 2005. [x1] Study connects echinacea, tract bacteria AP December 20, 2006. [11] Drs Pleschka S, Stein M, Schoop R. and Hudson JB Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian influenza virus (H5N1, H7N7) and swine-origin H1N1 (S-OIV). Virol J. 2009 Nov 13;6:197 [1A] Goel et al, J Nutr Biochem. 2002 Aug;13(8):487. [C1] Yu D et al, Anti-inflammatory effects of essential oil in Echinacea purpurea L. Pak J Pharm Sci. 2013 Mar;26(2):403-8. D1. O'Neill et al, Equine Vet J. 2002 May;34(3):222-7. D2. Saumya Choudhary et al, Immunomodulatory Effect of Phytoactive Compounds on Human Health: A Narrative Review Integrated with Bioinformatics Approach, Curr Top Med Chem. 2024 Mar 27. D3. Fan-Hao Wei et al, Echinacea purpurea Polysaccharide Ameliorates Dextran Sulfate Sodium-Induced Colitis by Restoring the Intestinal Microbiota and Inhibiting the TLR4-NF-κB Axis,Nutrients. 2024 Apr 26;16(9):1305.