Document Type
Thesis - University Access Only
Award Date
2005
Degree Name
Doctor of Philosophy (PhD)
Department / School
Chemistry and Biochemistry
Abstract
Echinacea phytopharmaceuticals have been touted for their numerous beneficial effects. One such effect is their anti-hyaluronidase activity, known for reducing the side effects of inflammatory responses. However, Echinacea products may have an undesirable effect specifically on chemotherapy. Hyaluronidase has been reported as an effective supplement to many common anti-cancer drugs, which suffer from the disadvantage of poor penetration into the mass of a tumor. A recent study revealed that a growing number of cancer patients are self-administering Echinacea products while undergoing chemotherapy. Since hyaluronidase inhibition may reduce the efficiency of chemotherapy including hyaluronidase, it is possible that Echinacea products may do more harm than good. The purpose of this study is to establish a possible link between Echinacea and the proliferation of cancer cells. Roots of E. angustifolia were ground to a powder, extracted with aqueous methanol, filtered, and concentrated in vacuo. The resulting extracts were screened for anti-hyaluronidase and antioxidant activity using spectrophotometric methods, as antihyaluronidase compounds have shown antioxidant activity according to previous literature. Active fractions were fractionated using solvent extractions and tested for antihyaluronidase activity and total phenolics. No correlation could be drawn between the total phenolics and the anti-hyaluronidase activity of the fractions. Two syntheses were conducted for chicoric acid and 1, 5-dicaffeoylquinic acid. The first was optimized from a literature method, while the second was a novel synthesis developed using caffeic acid and quinic acid as starting materials. The fractions, three compounds, and two commercial extracts were tested for proliferative activity on cervical and breast cancer cells. This was done on a combination of doxorubicin and hyaluronidase as well as doxorubicin alone. Doxorubicin was chosen because this is one such drug that can be enhanced with supplemental hyaluronidase. All fractions were tested on HeLa and breast cancer cell lines to determine proliferative activity on the cells treated with a combination of doxorubicin and hyaluronidase and doxorubicin alone. Cervical and breast cancer cell lines have been used in previous experiments as well, so they made an appropriate starting point. Proliferative activity was observed in the fractions, commercial extracts and individual compounds. Several Echinacea samples responded differently to different cell types. Each cell type indicated that the proliferative activity of Echinacea root extracts can be isolated in a few constituents rather than any arbitrary phenolic acid. In terms of interference, chicoric acid was the most interfering on MCF-7 cells, while cynarine was the most interfering on HeLa cells. Differences in activities between the two compounds could be attributed to differential cytotoxicity. Commercial extracts showed less response than the fractions, which could be due to the diversity in compounds in the extract and different origins from the fractionated Echinacea root extracts. The structure-activity relationship of the caffeoyl esters was conducted through GAMESS and GAUSSIAN molecular modeling software. The total valence of each atom was calculated using second-order Moller Plesset calculations. The total valence of each atom on a caffeoyl substituent was plotted against log (cell growth) values of HeLa cells treated with 10·2 mg/mL of the Echinacea compound and 5 x 104 mM doxorubicin. The Echinacea and doxorubicin concentrations used in the computations were part of a range of tested concentrations. Energy minimization and subsequent Moller-Plesset perturbation revealed a strong correlation between C6 and 09. This indicates that the movement of electrons through the caffeoyl substituent affects the proliferative or antiproliferative activity of caffeic acid and its esters.
Library of Congress Subject Headings
Echinacea (Plants)
Herbs -- Therapeutic use
Phytochemicals -- Physiological effect
Cancer cells -- Proliferation
Format
application/pdf
Number of Pages
160
Publisher
South Dakota State University
Recommended Citation
Huntimer, Eric, "Effect of Echinacea Angustifolia Root Extracts and Caffeic Acid Derivatives on Cancer Cell Proliferation" (2005). Electronic Theses and Dissertations. 1189.
https://openprairie.sdstate.edu/etd2/1189