A study published in the current issue of Breast Cancer Research and Treatment suggests that the black cohosh supplement RemiFemin Menopause can safely relieve menopausal symptoms in women with a history of breast cancer who cannot take oestrogen.
The study adds to the growing body of evidence showing that RemiFemin relieves symptoms without exerting an oestrogenic effect - welcome news for the many women who cannot, or who choose not to, take hormone replacement therapy (HRT).
"This is promising news for all women, especially those with a history of breast cancer, who are looking for estrogen-free alternatives to treat menopausal symptoms," said Dr Susan Love, a recognised authority on women's health, adjunct professor of surgery at UCLA, and the author of several books.
Hormone replacement therapy (HRT) is a commonly prescribed treatment for relief of menopausal symptoms, which affects a third of American women (more than 35 million) each year. However, the recent report from the Women's Health Initiative which raised concerns about long-term safety of HRT, will inevitably mean that many women choose to look for alternative treatments. Experts also recommend that women with oestrogen-sensitive cancers seek alternative methods for alleviating menopausal symptoms.
The research, conducted by Dr Johannes Freudenstein and colleagues, was designed to evaluate the safety of RemiFemin Menopause as an alternative for oestrogen-sensitive patients for whom HRT is contraindicated. The study examined and compared the effects of black cohosh extract, oestrogen, tamoxifen (an anti-oestrogen) and a placebo control on oestrogen-sensitive breast cancer cells.
To evaluate the safety and oestrogenic activity of RemiFemin, the researchers performed experiments using cultured oestrogen receptor-positive MCF-7 cells. The experiments tested for potential oestrogen-like activity of RemiFemin by examining the rate of growth of MCF-7 cells exposed to black cohosh extract as compared to both negative (placebo) and positive (oestrogen) controls, as well as tamoxifen.
When black cohosh was introduced to the cell model, in contrast to oestrogen, it did not stimulate growth. In fact, dilutions comparable to the commercially available dose of black cohosh extract (RemiFemin) resulted in significant inhibition of MCF-7 cell growth. Furthermore, black cohosh was found to enhance the inhibitory effect of tamoxifen, a commonly prescribed drug for treatment of breast cancer, which, as expected, significantly reduced cell proliferation.
"Unlike oestrogen, which stimulated cancerous cell growth in the human-breast cell system studied, RemiFemin did not have such a proliferative effect, confirming its safety in patients with a history of breast cancer. These data provide important evidence that black cohosh works differently than oestrogens and phytoestrogens to relieve the symptoms of menopause," noted pharmacologist and herbal expert Dr Steven Weisman.
However while herbal treatments are gaining popularity for relieving symptoms of menopause, data on the effectiveness of phytoestrogens, including soy and red clover, are uncertain. In addition, phytoestrogens, based on their mechanisms of action, may have effects that are similar to oestrogen in women at increased risk of female cancers.
GlaxoSmithkline, the marketers of RemiFemin in the US, claim that unlike oestrogens and phytoestrogens, its product has been shown to relieve menopause symptoms without oestrogen-like activity. This data is also supported by research reporting the non-oestrogenic effects of Remifemin in the breast, published in the June issue of Cancer Research.
Glaxo adds that the overall safety and efficacy of the supplement has been established through more than 20 clinical trials spanning more than 40 years with over 3,000 subjects. A study in the March 2002 issue of the Journal of Women's Health and Gender-Based Medicine presented the results of a controlled, randomised, double blind, clinical trial that showed RemiFemin decreased physical and emotional menopause symptoms in most women by 70 per cent after 12 weeks of twice-daily use, without altering hormone levels or affecting oestrogen receptor tissues.
RemiFemin has been evaluated and approved by the German Commission E, a regulatory body similar to the US FDA, as a treatment for menopausal symptoms, including hot flushes, mood swings, night sweats, irritability and related occasional sleeplessness.
The research was funded by Schaper & Brummer, a herbal company based in Salzgitter, Germany.