Clinical trial NCT00566553: The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women
Official title: The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women: A Pilot Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Breast Cancer
Keywords: Grape Seed Extract
Breast Cancer
Estrogen Levels
Aromatase Inhibitor
Lead sponsor: Mayo Clinic
Sponsor class: OTHER
First posted: 2007-12-03
Enrollment: 39
Sex: FEMALE
Minimum age (years): 55
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The role of estrogens in the pathogenesis of breast cancer has been well documented. This has led to the development of "Anti-Estrogens" (selective estrogens receptor modulators and Aromatase Inhibitors), used for treatment and prevention of breast cancer. These agents, however, have significant side effects, which are not acceptable to many healthy high-risk women. There is preliminary evidence that grape seed extract acts as "natural" aromatase inhibitor (1). This study has the potential to quantify the effectiveness of a natural substance that mimics the action of pharmaceutical aromatase inhibitors.

Detailed description: Early detection of breast cancer with screening mammography and the use of more effective medical therapies have led to a decrease in breast cancer mortality. However, breast cancer is still the second leading cause of cancer death in women (2). Therefore, the future lies in not only early detection but prevention of breast cancer. Currently available chemopreventive agents are associated with potentially serious side effects and can be quite costly, especially when taken for extended periods of time. Therefore, they are usually targeted only to women at high risk of disease. Identification of an inexpensive, efficacious preventive therapy with few or no side effects would represent a major advance in reducing the morbidity and mortality due to breast cancer. One exciting possibility is grape seed extract. Grapes and grape seeds contain procyanidins, a highly active subclass of flavonoids with actions similar to pharmaceutical aromatase inhibitors (AIs). These procyanidin dimers have been found to suppress estrogen biosynthesis both in vitro and in animal models (1). Based upon this knowledge we proposed this dose finding pilot study.

Eligibility criteria: Inclusion Criteria:

* Age 55 - 75 years
* Able to understand and sign a consent form
* Postmenopausal (no menstrual period for 1 year or more)
* No personal cancer history (except for non-melanoma skin cancer)
* No hormone replacement therapy or anti-estrogens within 6 months of baseline

Exclusion Criteria:

* Known allergy to grapes or grape products
* Currently on ACE inhibitors, methotrexate, allopurinol, coumadin (Warfarin, Jantoven), heparin, clopidogrel (Plavix), or cholesterol lowering medication

Primary outcomes:
measure: To document that grape seed extract taken orally will decrease plasma estrogen levels (estrone (E1), estradiol (E2), and E1-conjugates) and increase precursor androgen levels (testosterone and androstenedione) in healthy postmenopausal women.
timeFrame: 12 weeks
Secondary outcomes:
measure: To determine the most effective, well tolerated dose of grape seed extract resulting in a decrease in plasma estrogen levels (E1, E2, E1-conjugates) and increase in precursor androgens (testosterone and androstenedione).
timeFrame: 12 weeks
Other outcomes:
Locations:
city: Rochester
country: United States
facility: Mayo Clinic
state: Minnesota
Study officials:
affiliation: Mayo Clinic
name: Dietlind L. Wahner-Roedler, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Eng ET, Ye J, Williams D, Phung S, Moore RE, Young MK, Gruntmanis U, Braunstein G, Chen S. Suppression of estrogen biosynthesis by procyanidin dimers in red wine and grape seeds. Cancer Res. 2003 Dec 1;63(23):8516-22.
citation: American Cancer Society. Cancer Facts and Figures 2005. Atlanta, GA: American Cancer Society; 2005.