Disease relevance of Echinacea

• 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 [1].
• Commonly used supplements included ginseng, zinc, echinacea, ginkgo, weight loss supplements, and creatine [2].
• A woman with atopy experienced anaphylaxis after taking, among other dietary supplements, a commercial extract of echinacea [3].
• Adding an herb such as echinacea or Andrographis shortens the duration of the common cold [4].
• Fifteen patients with advanced gastric cancer undergoing palliative chemotherapy with etoposide, leucovorin and 5-fluorouracil (ELF) received for 10 days (beginning 3 days before chemotherapy) daily i.v. injections of 2 mg of a polysaccharide fraction isolated from Echinacea purpurea herb cell cultures (EPS-EPO VIIa) [5].

High impact information on Echinacea

• In this study, acidic arabinogalactan, a highly purified polysaccharide from plant cell cultures of Echinacea purpurea, with a molecular weight of 75,000, was effective in activating macrophages to cytotoxicity against tumor cells and micro-organisms (Leishmania enriettii) [6].
• However, Echinacea lacks the 1,2 saturated necrine ring associated with hepatoxicity of pyrrolizidine alkaloids [7].
• Immunostimulants (eg, Echinacea and zinc) should not be given with immunosuppressants (eg, corticosteroids and cyclosporine) [7].
• If used beyond 8 weeks, Echinacea could cause hepatotoxicity and therefore should not be used with other known hepatoxic drugs, such as anabolic steroids, amiodarone, methotrexate, and ketoconazole [7].
• The type of drug interaction observed between echinacea and other CYP3A substrates will be dependent on the relative extraction of drugs at hepatic and intestinal sites [8].

Biological context of Echinacea

• Macrophage activation by the polysaccharide arabinogalactan isolated from plant cell cultures of Echinacea purpurea [6].

Anatomical context of Echinacea

• Deleterious effects of Echinacea purpurea and melatonin on myeloid cells in mouse spleen and bone marrow [9].
• Cytochrome P450 enzyme-mediated degradation of Echinacea alkylamides in human liver microsomes [10].
• OBJECTIVE: To study the effect of Echinacea tablets on the expression of leucocyte heat shock protein 70 (hsp70), erythrocyte haemolysis, plasma antioxidant status, serum chemistry, haematological values and plasma alkylamide concentrations [11].

Associations of Echinacea with chemical compounds

• Echinacea dosing significantly reduced the oral clearance of caffeine, from 6.6 +/- 3.8 L/h to 4.9 +/- 2.3 L/h (P =.049; 90% CI, 58%-96%) [8].
• Caffeine, tolbutamide, dextromethorphan, and oral and intravenous midazolam were administered before and after a short course of echinacea (400 mg 4 times a day for 8 days) to determine in vivo CYP activities [8].
• In contrast, Echinacea extracts chemically standardized to phenolic acid or echinacoside content and fresh pressed juice preparations were found to be inactive as immunostimulatory agents but did display, to varying degrees, anti-inflammatory and antioxidant properties [12].
• Preparative separation of cichoric acid from Echinacea purpurea by pH-zone-refining counter-current chromatography [13].
• Analysis of alkamides and caffeic acid derivatives from Echinacea simulata and E. paradoxa roots [14].

Gene context of Echinacea

• Echinacea selectively modulates the catalytic activity of CYP3A at hepatic and intestinal sites [8].
• The oral clearance of dextromethorphan in 11 CYP2D6 extensive metabolizers was not affected by echinacea dosing (1289 +/- 414 L/h compared with 1281 +/- 483 L/h; P =.732; 90% CI, 89%-108%) [8].
• Caution should be used when echinacea is coadministered with drugs dependent on CYP3A or CYP1A2 for their elimination [8].
• CONCLUSIONS: Echinacea (E purpurea root) reduced the oral clearance of substrates of CYP1A2 but not the oral clearance of substrates of CYP2C9 and CYP2D6 [8].
• Echinacea induced lower levels of IL-6 in comparison to the other cytokines measured [15].

Analytical, diagnostic and therapeutic context of Echinacea

• HPLC method validated for the simultaneous analysis of cichoric acid and alkamides in Echinacea purpurea plants and products [16].

References