Cimicifuga racemosa
Encyclopedia
Actaea racemosa is a plant of the buttercup family (Ranunculaceae
). It is native to eastern North America
from the extreme south of Ontario
to central Georgia
, and west to Missouri
and Arkansas
. Black cohosh grows in a variety of woodland habitat
s, and is often found in small woodland openings. The root
s and rhizome
s of black cohosh have long been used medicinally by Native Americans
. Extracts from these plant materials are thought to possess analgesic
, sedative
, and anti-inflammatory
properties. Today, black cohosh preparations (tinctures or tablets of dried materials) are used mainly to treat symptoms associated with menopause
.
perennial plant
that produces large, compound leaves from an underground rhizome, reaching a height of 25–60 cm (9.8–23.6 ). The basal leaves
are up to 1 metres (3.3 ft) long and broad, forming repeated sets of three leaflets (tripinnately compound) having a coarsely toothed (serrated) margin. The flower
s are produced in late spring and early summer on a tall stem, 75–250 cm (29.5–98.4 ) tall, forming raceme
s up to 50 centimetres (19.7 in) long. The flowers have no petal
s or sepal
s, and consist of tight clusters of 55-110 white, 5–10 mm long stamen
s surrounding a white stigma. The flowers have a distinctly sweet, fetid smell that attracts flies, gnat
s, and beetles. The fruit
is a dry follicle
5–10 mm long, with one carpel, containing several seed
s.
has a history of taxonomic uncertainty dating back to Carl Linnaeus, who—based on morphological characteristics of the inflorescence
and seeds—had placed the species into the genus, Actaea
. This designation was later revised by Thomas Nuttall
reclassifying the species to the genus, Cimicifuga
. Nuttall's classification was based solely on the dry follicles produced by black cohosh, which are typical of species in Cimicifuga. However, recent data from morphological and gene
phylogeny analyses demonstrate that black cohosh is more closely related to species of the genus Actaea than to other Cimicifuga species. This has prompted the revision to Actaea racemosa as originally proposed by Linnaeus. Blue cohosh (Caulophyllum thalictroides
), despite its similar common name belongs to another family
, the Berberidaceae
, and is therefore not closely related to black cohosh.
used black cohosh to treat gynecological and other disorders, including sore throat
s, kidney problems, and depression
. Following the arrival of European settlers in the U.S. who continued the medicinal usage of black cohosh, the plant appeared in the U.S. Pharmacopoeia in 1830 under the name “black snakeroot”. In 1844 A. racemosa gained popularity when Dr. John King, an eclectic physician
, used it to treat rheumatism and nervous disorders. Other eclectic physicians of the mid-nineteenth century used black cohosh for a variety of maladies, including endometritis, amenorrhea, dysmenorrhea, menorrhagia, sterility, severe after-birth pains, and for increased breast milk production.
marketed to women as remedies for the symptoms of premenstrual tension, menopause and other gynecological problems. However, its usage for treating these ailments is controversial, with some studies casting doubt on its efficacy. Study design and dosage of black cohosh preparations play a role in clinical outcome, and recent investigations with pure compounds found in black cohosh have identified some beneficial effects of these compounds on physiological pathways underlying age-related disorders like osteoporosis
. According to some placebo
-controlled studies that included a sufficiently high number of participants to determine statistical significance
of clinical outcomes, the use of black cohosh appears to be safe, but ineffective for treating menopausal hot flashes. Black cohosh extracts have been reported to have vasorelaxant activities.
with biological activity
.
Estrogen-like compounds
had originally been implicated in effects of black cohosh extracts on vasomotor symptoms in menopausal women. Several other studies, however, have indicated absence of estrogenic effects and compounds in black cohosh-containing materials. Recent findings suggest that some of the clinically relevant physiological effects of black cohosh may be due to compounds that bind and activate serotonin
receptors, and a derivative of serotonin with high affinity to serotonin receptors
, Nω-methylserotonin, has been identified in black cohosh. Complex biological molecules
, such as triterpene
glycoside
s (e.g. cycloartanes
), have been shown to reduce cytokine
-induced bone loss (osteoporosis
) by blocking osteoclast
ogenesis in in vitro and in vivo models.
ic effects on the breast.
No studies exist on long-term safety of black cohosh use in humans. In a transgenic mouse model of cancer
, black cohosh did not increase incidence of primary breast cancer, but increased metastasis of pre-existing breast cancer to the lungs.
Liver damage
has been reported in a few individuals using black cohosh, but many women have taken the herb without reporting adverse health effects, and a meta-analysis of several well-controlled clinical trials found no evidence that black cohosh preparations have any adverse effect on liver function.
Despite a lack of conclusive evidence for a link between black cohosh and liver damage, Australia has added a warning to the label of all black cohosh-containing products, stating that it may cause harm to the liver in some individuals and should not be used without medical supervision. Other studies conclude that liver damage from use of black cohosh is unlikely, and that the main concern over its safe use is lack of proper authentication of plant materials and adulteration of commercial preparations with other plant species.
Reported direct side-effects also include dizziness, headaches, and seizures; diarrhea
; nausea
and vomiting; sweating; constipation
; low blood pressure and slow heartbeats; and weight problems.
Because the vast majority of black cohosh materials are harvested from plants growing in the wild, a recurring concern regarding the safety of black cohosh-containing dietary supplements is mis-identification of plants causing unintentional mixing-in (adulteration) of potentially harmful materials from other plant sources.
Ranunculaceae
Ranunculaceae are a family of about 1700 species of flowering plants in about 60 genera, distributed worldwide....
). It is native to eastern North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
from the extreme south of Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
to central Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
, and west to Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
and Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
. Black cohosh grows in a variety of woodland habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s, and is often found in small woodland openings. The root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s and rhizome
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
s of black cohosh have long been used medicinally by Native Americans
Indigenous peoples of the Americas
The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...
. Extracts from these plant materials are thought to possess analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
, sedative
Sedative
A sedative or tranquilizer is a substance that induces sedation by reducing irritability or excitement....
, and anti-inflammatory
Anti-inflammatory
Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....
properties. Today, black cohosh preparations (tinctures or tablets of dried materials) are used mainly to treat symptoms associated with menopause
Menopause
Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries: the ripening and release of ova and the release of hormones that cause both the creation of the uterine lining and the subsequent shedding of the uterine lining...
.
Description
Black cohosh is a smooth (glabrous), herbaceousHerbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
perennial plant
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
that produces large, compound leaves from an underground rhizome, reaching a height of 25–60 cm (9.8–23.6 ). The basal leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are up to 1 metres (3.3 ft) long and broad, forming repeated sets of three leaflets (tripinnately compound) having a coarsely toothed (serrated) margin. The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are produced in late spring and early summer on a tall stem, 75–250 cm (29.5–98.4 ) tall, forming raceme
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
s up to 50 centimetres (19.7 in) long. The flowers have no petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s or sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s, and consist of tight clusters of 55-110 white, 5–10 mm long stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s surrounding a white stigma. The flowers have a distinctly sweet, fetid smell that attracts flies, gnat
Gnat
A gnat is any of many species of tiny flying insects in the Dipterid suborder Nematocera, especially those in the families Mycetophilidae, Anisopodidae and Sciaridae.In British English the term applies particularly to Nematocerans of the family Culicidae...
s, and beetles. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is a dry follicle
Follicle (fruit)
In botany, a follicle is a dry unilocular many-seeded fruit formed from one carpel and dehiscing by the ventral suture in order to release seeds, such as in larkspur, magnolia, banksia, peony and milkweed....
5–10 mm long, with one carpel, containing several seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s.
Taxonomy
The plant speciesSpecies
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
has a history of taxonomic uncertainty dating back to Carl Linnaeus, who—based on morphological characteristics of the inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
and seeds—had placed the species into the genus, Actaea
Actaea
Actaea, commonly called baneberry or bugbane, is a genus of flowering plants belonging to the family Ranunculaceae, native to temperate regions of the Northern Hemisphere....
. This designation was later revised by Thomas Nuttall
Thomas Nuttall
Thomas Nuttall was an English botanist and zoologist, who lived and worked in America from 1808 until 1841....
reclassifying the species to the genus, Cimicifuga
Cimicifuga
Cimicifuga is a genus of between 12-18 species of flowering plants belonging to the family Ranunculaceae, native to temperate regions of the Northern Hemisphere....
. Nuttall's classification was based solely on the dry follicles produced by black cohosh, which are typical of species in Cimicifuga. However, recent data from morphological and gene
Multilocus sequence typing
Multilocus sequence typing is a technique in molecular biology for the typing of multiple loci. The procedure characterizes isolates of bacterial species using the DNA sequences of internal fragments of multiple housekeeping genes...
phylogeny analyses demonstrate that black cohosh is more closely related to species of the genus Actaea than to other Cimicifuga species. This has prompted the revision to Actaea racemosa as originally proposed by Linnaeus. Blue cohosh (Caulophyllum thalictroides
Blue Cohosh
Blue cohosh a species of Caulophyllum and family Berberidaceae, also called squaw root or papoose root, is a flowering plant in the Berberidaceae family...
), despite its similar common name belongs to another family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
, the Berberidaceae
Berberidaceae
Berberidaceae are a family of 15 genera flowering plants commonly called the barberry family. This family is in the order Ranunculales. The family contains about 570 species, of which the majority are in Berberis...
, and is therefore not closely related to black cohosh.
Historical use
Native AmericansIndigenous peoples of the Americas
The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...
used black cohosh to treat gynecological and other disorders, including sore throat
Sore throat
A sore throat or throat pain is a common physical symptom usually caused by acute pharyngitis, or throat inflammation, though it also occurs in a number of other situations, such as post trauma and in diphtheria. It can cause mild to extreme pain....
s, kidney problems, and depression
Depression (mood)
Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behaviour, feelings and physical well-being. Depressed people may feel sad, anxious, empty, hopeless, helpless, worthless, guilty, irritable, or restless...
. Following the arrival of European settlers in the U.S. who continued the medicinal usage of black cohosh, the plant appeared in the U.S. Pharmacopoeia in 1830 under the name “black snakeroot”. In 1844 A. racemosa gained popularity when Dr. John King, an eclectic physician
Eclectic medicine
Eclectic medicine was a branch of American medicine which made use of botanical remedies along with other substances and physical therapy practices, popular in the latter half of the 19th and first half of the 20th centuries....
, used it to treat rheumatism and nervous disorders. Other eclectic physicians of the mid-nineteenth century used black cohosh for a variety of maladies, including endometritis, amenorrhea, dysmenorrhea, menorrhagia, sterility, severe after-birth pains, and for increased breast milk production.
Contemporary use
Black cohosh is used today mainly as dietary supplementDietary supplement
A dietary supplement, also known as food supplement or nutritional supplement, is a preparation intended to supplement the diet and provide nutrients, such as vitamins, minerals, fiber, fatty acids, or amino acids, that may be missing or may not be consumed in sufficient quantities in a person's diet...
marketed to women as remedies for the symptoms of premenstrual tension, menopause and other gynecological problems. However, its usage for treating these ailments is controversial, with some studies casting doubt on its efficacy. Study design and dosage of black cohosh preparations play a role in clinical outcome, and recent investigations with pure compounds found in black cohosh have identified some beneficial effects of these compounds on physiological pathways underlying age-related disorders like osteoporosis
Osteoporosis
Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...
. According to some placebo
Placebo
A placebo is a simulated or otherwise medically ineffectual treatment for a disease or other medical condition intended to deceive the recipient...
-controlled studies that included a sufficiently high number of participants to determine statistical significance
Statistical significance
In statistics, a result is called statistically significant if it is unlikely to have occurred by chance. The phrase test of significance was coined by Ronald Fisher....
of clinical outcomes, the use of black cohosh appears to be safe, but ineffective for treating menopausal hot flashes. Black cohosh extracts have been reported to have vasorelaxant activities.
Bioactive compounds
Like most plants, black cohosh tissues and organs contain many organic compoundsNatural product
A natural product is a chemical compound or substance produced by a living organism - found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design...
with biological activity
Biological activity
In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore but can be modified by the other...
.
Estrogen-like compounds
Phytoestrogens
Phytoestrogens are plant-derived xenoestrogens functioning as the primary female sex hormone not generated within the endocrine system but consumed by eating phytoestrogonic plants...
had originally been implicated in effects of black cohosh extracts on vasomotor symptoms in menopausal women. Several other studies, however, have indicated absence of estrogenic effects and compounds in black cohosh-containing materials. Recent findings suggest that some of the clinically relevant physiological effects of black cohosh may be due to compounds that bind and activate serotonin
Serotonin
Serotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...
receptors, and a derivative of serotonin with high affinity to serotonin receptors
5-HT7 receptor
The 5-HT7 receptor is a member of the GPCR superfamily of cell surface receptors and is activated by the neurotransmitter serotonin The 5-HT7 receptor is coupled to Gs and is expressed in a variety of human tissues, particularly in the brain, the gastrointestinal tract, and in various...
, Nω-methylserotonin, has been identified in black cohosh. Complex biological molecules
Small molecule
In the fields of pharmacology and biochemistry, a small molecule is a low molecular weight organic compound which is by definition not a polymer...
, such as triterpene
Triterpene
Triterpenes are terpenes consisting of six isoprene units and have the molecular formula C30H48.The pentacyclic triterpenes can be classified into lupane, oleanane or ursane groups.Animal- and plant-derived triterpenes exist, such as:*squalene...
glycoside
Glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to a non-carbohydrate moiety, usually a small organic molecule. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme...
s (e.g. cycloartanes
Cycloartenol
Cycloartenol is an important type of stanol found in plants. The biosynthesis of cycloartenol starts from the triterpenoid squalene. It is the first precursor in the biosynthesis of other stanols and sterols, referred to as phytostanols and phytosterols in photosynthetic organisms and plants...
), have been shown to reduce cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
-induced bone loss (osteoporosis
Osteoporosis
Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...
) by blocking osteoclast
Osteoclast
An osteoclast is a type of bone cell that removes bone tissue by removing its mineralized matrix and breaking up the organic bone . This process is known as bone resorption. Osteoclasts were discovered by Kolliker in 1873...
ogenesis in in vitro and in vivo models.
Side effects
Studies on human subjects who were administered two commercially available black cohosh preparations did not detect estrogenEstrogen
Estrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...
ic effects on the breast.
No studies exist on long-term safety of black cohosh use in humans. In a transgenic mouse model of cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
, black cohosh did not increase incidence of primary breast cancer, but increased metastasis of pre-existing breast cancer to the lungs.
Liver damage
Hepatotoxicity
Hepatotoxicity implies chemical-driven liver damage.The liver plays a central role in transforming and clearing chemicals and is susceptible to the toxicity from these agents. Certain medicinal agents, when taken in overdoses and sometimes even when introduced within therapeutic ranges, may injure...
has been reported in a few individuals using black cohosh, but many women have taken the herb without reporting adverse health effects, and a meta-analysis of several well-controlled clinical trials found no evidence that black cohosh preparations have any adverse effect on liver function.
Despite a lack of conclusive evidence for a link between black cohosh and liver damage, Australia has added a warning to the label of all black cohosh-containing products, stating that it may cause harm to the liver in some individuals and should not be used without medical supervision. Other studies conclude that liver damage from use of black cohosh is unlikely, and that the main concern over its safe use is lack of proper authentication of plant materials and adulteration of commercial preparations with other plant species.
Reported direct side-effects also include dizziness, headaches, and seizures; diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
; nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
and vomiting; sweating; constipation
Constipation
Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation...
; low blood pressure and slow heartbeats; and weight problems.
Because the vast majority of black cohosh materials are harvested from plants growing in the wild, a recurring concern regarding the safety of black cohosh-containing dietary supplements is mis-identification of plants causing unintentional mixing-in (adulteration) of potentially harmful materials from other plant sources.