Black Cohosh Root

SCIENTIFIC NAME : Cimicifuga Racemosa

COMMON NAME : Black cohosh, baneberry, black snakeroot, bugbane, squawroot, rattle root

BOTANY

Black cohosh grows in open woods at the edges of dense forests from Ontario to Tennessee and west to Missouri. This perennial grows to 8 feet and is topped by a long plume of white flowers that bloom from June to September. Its leaflets are shaped irregularly with toothed edges. The term "black" refers to the dark color of the rhizome. The name "cohosh" comes from an Algon­quian word meaning "rough," referring to the feel of the rhizome.

HISTORY

The roots and rhizomes of this herb are used medicinally. Traditional uses include the treatment of dysmenorrhea, dyspepsia and rheumatisms. A tea from the root has been recommended for sore throat. The Latin name cimicifuga means "bug-repellent" and the plant has been used for this purpose. American Indians used the plant to treat snakebites.

Old time remedy "Lydia Pinkham's Vegetable Compound" (early 1900s) contained many natural ingredients, one of which was black cohosh.

Remifemin, the brand-name of the standardized extract of the plant, has been used in Germany for menopausal management since the mid-1950s.

CHEMISTRY

German reports from the late 1960s dis­cussing the contents of black cohosh (eg, acetin) are available.

Black cohosh contains alkaloids including N-methyl­cytisine and others, tannins and terpenoids. The terpe­noid mixture consists of actein, 12-acetylactein and cimi­goside. Other constituents found in the plant include acetic, butyric, formic, isoferulic, oleic, palmitic and sali­cylic acids, racemosin, formononetin (an isoflavone), phy­tosterols, acteina (resinous mixture) and volatile oil.

An amorphous resinous substance called cimicifugin (macrotin) accounts for approximately 15% to 20% of the root. Cimigoside (cimifugoside) and 27-deoxyactein have also been isolated.

PHARMACOLOGY

The purported estrogenic effects of the plant could not be reproduced in extensive tests in In one study, there was no evidence of a direct or indirect influence on gonadal function. However, other studies indicate that methanol extracts of C. Racemosa contain substances that bind to estrogen receptors. Intraperitoneal injection of the extract in ovariectomized rats caused a selective reduction in luteinizing hormone (LH) level with almost no effect on follicle-stimulating hormone (FSH) or prolactin levels.

In women treated for 8 weeks with the commercial product Remifemin and luteinizing hormone but not fol­licle-stimulating hormone, levels were reduced significantly. This product is used for the management of menopausal hot flashes. Analysis of the commercial product identified at least three fractions that contribute synergistically to the suppression of LH and bind to estrogen receptors. These data suggest that black co­hosh has a measurable effect on certain reproductive hormones. The product may offer an alternative to conventional hormone replacement therapy (HRT). In patient populations with a history of estrogen~dependent cancer (although it possesses some estrogenic activity), Remifemin shows no stimulatory effects on established breast tumor cell lines dependent on estrogen's pres­ence. Instead, inhibitory actions were seen. In addition, the product exerts no effect on endometrium, so there is no need to "oppose" therapy with progesterone as with conventional HRT. The plant extract's action proves to be more like estriol than estradiol, which is associated with higher risk for breast, ovarian and endometrial cancers. Estriol exerts its effects mainly on the vaginal lining rather than the uterine lining, as estradiol does. More studies are needed, however, to address osteoporosis and bone health with use of the product.

One report finds no signs of uterine growth and vaginal cornification in ovariectomized rats given black cohosh extract. This helps to confirm that the plant's beneficial effects on menopausal discomfort cannot be explained as the traditional estrogenic type.

A clinical and endocrinologic study has been performed in 60 patients under 40 years old who had hysterectomies. Four randomized treatment groups included estriol, con­jugated estrogens, estrogen-gestagen sequential therapy or black cohosh extract. Results of this report showed no significant differences between groups in success of therapy.