Schisandra

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Schisandra

Description

Schisandra (Schisandra chinensis ) is an aromatic woody vine that is native to northern and northeastern China. It is predominately cultivated in the Chinese provinces of Jilin, Hebei, Heilongjiang, and Lianoning. Schisandra is also found in Russia and Korea.

The schisandra plant reaches a height of up to 25 ft (7.5 m) and has pink flowers. Schisandra fruit is fully ripened in the fall and appears as numerous spikes of tiny, bright red berries. The berries have sweet, sour, hot, salty and bitter tastes—hence the Chinese name for schisandra, "Wu Wei Zi" (five-flavored herb). Other names for schisandra include schizandra, five-taste fruit, and herb of five tastes.

Constituents and bioactivities

Schisandra fruit contains a wide variety of compounds with biological activities. Constituents of schisandra include:

acids
lignans (deoxyschizandrin, gomisins, pregomisin, schizandrin, and others)
phytosterols (beta-sitosterol and stigmasterol)
vitamins C and E
volatile oils

Schisandra fruit contains at least 30 different lignans. Lignans, which are sometimes described as phytoestrogens (plant-derived compounds with estrogen-like activity), are known to have liver-protective (anti-hepatotoxic) action and to regenerate damaged liver tissue. In addition, lignans interfere with a compound called platelet activating factor, which promotes inflammation. The results of a study in rats showed that a lignan-enriched extract of Schisandra chinensis protected against liver damage from either aflatoxin (a toxin produced by a mold) or cadmium chloride (a toxic chemical). The liver-protective function is partly due to schisandra's antioxidant activity. However, treating the rats with vitamin E , an antioxidant, did not protect them from liver damage. This finding indicates that schisandra's liverprotective activity is not due to its vitamin E content. Schisandra increases liver function, which helps the body's metabolism become more efficient.

Research has shown that schisandra has adaptogenic properties, which means that it helps the body to fight disease and adapt to stresses from physical, mental, chemical, and environmental sources. Schisandra also has tonic (restoring tone to tissues), expectorant (promoting the clearing of lung mucus), and cough-suppressant (reducing coughing) activities. It stimulates the nervous system by increasing the speed of nervous responses, leading to quicker and stronger reflexes. Schisandra has been shown to stimulate breathing, lower blood pressure, act as a vasodilator (causing blood vessels to dilate), improve blood circulation, improve heart function, strengthen uterine contractions, improve vision, normalize blood sugar levels, and assist in food digestion and absorption of nutrients. It can activate all major body systems.

General use

Schisandra is a Chinese tonic herb used in traditional Chinese medicine as a lung astringent and kidney tonic. Historically, it was used to treat mental illness, night sweats, coughs, thirst, insomnia , chronic dysentery (diarrhea containing blood and mucus), premature ejaculation, and physical exhaustion. The Chinese consider it an energy tonic that can be used to restore lost vitality. Schisandra can improve overall health and increase energy levels.

Schisandra is an overall tonic that is used to treat the following conditions:

Fluid imbalance. Because of its kidney tonic effect, schisandra is useful in treating thirst, night sweats, excessive sweating, urinary incontinence , and the frequent urge to urinate.
Circulatory disorders. Schisandra may be used to treat poor circulation and poor heart function.
Intestinal disease. Schisandra has been used to treat diarrhea and dysentery.
Fatigue . Schisandra may help to reduce fatigue, improve endurance, improve work performance, and build strength. It is recommended for persons who need high levels of energy, such as athletes.
Liver disease. Schisandra is used to treat hepatitis and poor liver function. In one clinical study, schisandra successfully treated 76% of the patients with hepatitis. It has been shown to improve both virally and chemically induced hepatitis. More recently, schisandra has been found to protect the liver against the side effects of anti-Alzheimer's medications.
Mental and emotional illness. Schisandra has been shown to improve mental clarity, concentration, and coordination. It reduces forgetfulness, irritability, and nervous exhaustion. Schisandra is used to treat stress and may be part of a useful treatment for depression.
Respiratory disease and disorder. Schisandra is used to treat allergies . It treats respiratory symptoms such as shortness of breath, chronic cough , and wheezing.
Sensory organ failure. Schisandra has been used to help improve failing sight and hearing. It enhances the sensation of touch.
Sexual disorder. Schisandra tones the sexual organs of both men and women. It increases the production of sexual fluids, improves male sexual stamina, and treats premature ejaculation and low sex drive.
Skin rash. Schisandra has been used to treat skin conditions, including hives and eczema.
Sleep disorder. Because of its adaptogenic properties, schisandra can relieve insomnia and dream-disrupted sleep.
Other. Schisandra counteracts respiratory paralysis caused by morphine overdose, and strengthens uterine contractions to promote healthy labor and childbirth.

Schisandra is one of nine herbs combined in a Chinese dietary supplement called Equiguard, which is given to support the functioning of the kidneys and prostate gland in men. A recent study indicates that Equiguard may be helpful in treating prostate cancer because it appears to prevent the cancer cells from forming new colonies.

Preparations

Only the fruit of schisandra is used for medicinal purposes. Schisandra berries are harvested when fully ripe and allowed to dry in the sun. Schisandra's dried fruit is used, and the herb is prepared in the form of powder, tincture (an alcoholic extract), and wine. It is also found, usually in combination with other herbs, in capsules, tea, and decoctions (a water extract). Schisandra may be found in Chinese herb shops or health food stores. Recommended doses of schisandra are 1.5–15 g of dried fruit daily, 2–4 ml of tincture three times daily, 1.5–6 g of powder daily, one to three cups of tea once daily, or 1.5 g in capsule form daily.

The decoction is prepared by boiling 5 g of crushed berries in 100 ml of water. This decoction is divided into three doses, which are taken over a 24-hour period. The tea is prepared by steeping 1–6 g of dried schisandra berries in one to three cups of boiling water.

For use as a general tonic in China, patients are advised to chew dried schisandra berries daily for 100 days. Skin conditions are usually treated with a medicinal wine formulation.

It may take several weeks for the energy-increasing effects of schisandra to be felt.

Precautions

Schisandra should not be used during pregnancy or in patients who are having trouble urinating.

Side effects

Schisandra is safe for long-term use; it has relatively few side effects. It has, however, been reported to cause upset stomach, heartburn , decreased appetite, and skin rash.

Interactions

Schisandra interacts with acetaminophen in a positive way. In a laboratory study, gomisin A, a lignan found in schisandra, offered some degree of liver protection to rats given doses of acetaminophen high enough to cause liver damage.

Schisandra has been reported to increase the effects of antidiabetic medications and anesthetics; it should therefore be discontinued before major surgery. Schisandra should not be taken together with terfenadine (seldane) because it appears to increase the risk of cardiac arrhythmia as a side effect of this medication.

Schisandra is often used in Chinese herbal formulas as a harmonizing agent because it complements and coordinates well with other herbs. Schisandra is often found in combination with Korean ginseng (Panax ginseng ).

Resources

BOOK

Chevallier, Andrew. "Schisandra." In The Encyclopedia of Medicinal Plants. New York: DK Publishing, 1996.

PERIODICALS

Hsieh, T. C., X. Lu, J. Guo et al. "Effects of Herbal Preparation Equiguard on Hormone-Responsive and Hormone-Refractory Prostate Carcinoma Cells: Mechanistic Studies." International Journal of Oncology 20 (April 2002): 681-689.

Ip, Siu Po, et al. "Effect of a Lignan-Enriched Extract of Schisandra Chinensis on Aflatoxin B1 and Cadmium Chloride-Induced Hepatotoxicity in Rats." Pharmacology & Toxicology 78 (1996): 413–416.

Pan, S. Y., Y. F. Han, P. R. Carlier, et al. "Schisandrin B Protects Against Tacrine- and Bis(7)-Tacrine-Induced Hepatotoxicity and Enhances Cognitive Function in Mice." Planta Medica 68 (March 2002): 217-220.

Schar, Douglas. "5 Cutting-Edge Superherbs." Prevention 51 (December 1999): 110+.