MedPath

The Effect of Grape Seed Extract on Estrogen Levels of Postmenopausal Women

Not Applicable
Completed
Conditions
Breast Cancer
Interventions
Dietary Supplement: Grape Seed Extract
Registration Number
NCT00566553
Lead Sponsor
Mayo Clinic
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.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
39
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

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Grape Seed Extract # 3Grape Seed Extract200 mg \[3 pills\]
Grape Seed Extract # 1Grape Seed Extract200 mg \[1 pill\]
Grape Seed Extract # 2Grape Seed Extract200 mg \[2 pills\]
Grape Seed Extract # 4Grape Seed Extract200 mg \[4 pills\]
Primary Outcome Measures
NameTimeMethod
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.12 weeks
Secondary Outcome Measures
NameTimeMethod
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).12 weeks

Trial Locations

Locations (1)

Mayo Clinic

🇺🇸

Rochester, Minnesota, United States

© Copyright 2025. All Rights Reserved by MedPath