In vitro analysis of the herbal compound Essiac.
BACKGROUND
Despite the recommendation of the Task Force on Alternative Therapies of the Canadian Breast Cancer Research Initiative, little research has been published on the widely used herbal compound Essiac. We aimed to address this deficiency by conducting a series of assays to determine some of the purported activities of Essiac in vitro.


METHODS
The activity of Essiac was measured using established assays to assess anti-oxidant, fibrinolytic, anti-microbial, anti-inflammatory, immune modulation, cell-specific cytotoxicity, and impact on cytochrome P450 (CYP450) enzyme pathways.


RESULTS
Essiac exhibited significant antioxidant activity in the ABTS assay. A 20-fold dilution of Essiac also exhibited significant immunomodulatory effects, specifically through stimulation of granulocyte phagocytosis, increases in CD8+ cell activation, and moderately inhibiting inflammatory pathways. Essiac exhibited significant cell-specific cytotoxicity towards ovarian epithelial carcinoma cells (A2780). Importantly, a 20-fold dilution of Essiac showed significant inhibition of several CYP450 enzymes, most notably CYP1A2 (37%) and CYP2C19 (24%). Essiac demonstrated dose-dependent inhibition of clot fibrinolysis.


CONCLUSIONS
In vitro analysis of Essiac indicates significant antioxidant and immunomodulatory properties, as well as neoplastic cell specific cytotoxicity consistent with the historical properties ascribed to this compound. Importantly, significant CYP450 and fibrinolysis inhibition were also observed. This is the first comprehensive investigation of the in vitro effects of Essiac.
Seely
Dugald
D
Department of Research and Clinical Epidemiology, The Canadian College of Naturopathic Medicine, Toronto, ON, Canada. dseely@ccnm.edu
Kennedy
Deborah A
DA
Myers
Stephen P
SP
Cheras
Phillip A
PA
Lin
David
D
Li
Rachel
R
Cattley
Trudy
T
Brent
Petta-Anne Paul
PA
Mills
Edward
E
Leonard
Blair J N
BJ
D000890:Anti-Infective Agents / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D045744:Cell Line, Tumor; D065607:Cytochrome P-450 Enzyme Inhibitors; D004354:Drug Screening Assays, Antitumor; D005343:Fibrinolytic Agents / Q000494:pharmacology; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects
D000890:Anti-Infective Agents; D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D065607:Cytochrome P-450 Enzyme Inhibitors; C111756:Essiac; D005343:Fibrinolytic Agents; D010936:Plant Extracts