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From The January 2001 Issue of Nutrition Science News
Schisandra Berries More Than a Liver Aid
Berries from the plant (Schisandra chinensis) have been one of the primary medicinal agents of Chinese herbal medicine since antiquity. The first recorded use of schisandra is found in China's earliest text of herbal medicine, the Divine Husbandman's Classic of the Materia Medica, which is believed to have originated in the first century B.C.1 In it, schisandra is said to "prolong the years of life without aging," and it is also said to increase energy (called "qi," pronounced "chee"), suppress cough, treat fatigue and act as a sexual tonic in men.
In Traditional Chinese Medicine (TCM), schisandra berries have been used predominantly for the lungs and kidneys as an astringent tonic to arrest mucous discharges, alleviate spontaneous sweating and check urinary and reproductive secretions such as in urinary incontinence and spermatorrhea, an involuntary loss of semen.
More recently, the focus of schisandra research has been on its use in treating diabetes mellitus. Additionally, a protective effect on cardiovascular tissue insulted with chemical agents or ischemia has also been shown in vivo. As well, anti-inflammatory activity has been reported in in vitro, animal models, and clinical studies. The most important area, however, is in treating liver damage in conditions such as hepatitis. Schisandra is included in the pharmacopoeias of China, Japan, North and South Korea, and Russia, places where the plant grows naturally.
Pharmacological research on schisandra has been conducted since the 1950s, when it was reported to exhibit central nervous system stimulatory activity, enhance mental and physical capacities and improve cardiovascular function. These studies, mostly conducted in the former Soviet Union, characterize schisandra as an adaptogen and resulted in its popular use as a tonic.
Schisandra's constituents of interest in the majority of chemical and pharmacological research are the dibenzo[a,c]cyclooctadiene lignans that have been isolated from the unhydrolyzed fraction of the seed oil. These substances possess a unique structure and are among the lignans characterized by the presence of an aryl-aryl bond and an 8-member carbon ring. Approximately 40 lignans of S. chinensis have thus far been characterized.2
Protects The Liver
In China, crude schisandra berries, their preparations, and individual constituents are widely used for progressive hepatic degeneration due to viral hepatitis or chemical challenge—indications for which schisandra is well documented.3-6
In the 1970s, trials in China on patients with hepatitis resulting from either viral infection or chemical exposure reported schisandra preparations lowered elevated levels of serum glutamic-pyruvic transaminase (SGPT), an enzyme found primarily in the liver that is released into the bloodstream as the result of liver damage. This research focused on the antihepatotoxic effects of lignans isolated from the unhydrolyzed fraction of the seed oil. At least 13 of these lignans have been reported to enhance the hepatic glutathione antioxidant system and have been reported to be beneficial in treating viral- and chemical-induced hepatitis and liver cancer.
In 1986, Chinese researchers reported more than 5,000 cases of various types of hepatitis have been treated with schisandra preparations, resulting in the reduction of elevated liver enzymes.7 According to researchers, elevated SGPT values returned to normal in 75 percent of patients treated after 20 days of taking an unspecified schisandra preparation. In subjects with elevated SGPT attributed to drug toxicity, SGPT levels returned to normal in 83 out of 86 cases after one to four weeks of treatment.
A controlled study was conducted in China with 189 chronic viral hepatitis B patients with elevated SGPT levels.8 Tablets prepared from an ethanol berry extract containing 20 mg of lignans and corresponding to 1.5 g crude herb were administered to 107 of these patients. The control group of 82 patients was given liver extracts and vitamins. Normal SGPT levels were observed in 73 patients, or 68 percent, in the schisandra-treated group, with a four-week average time needed for normalization. In the control group, normal SGPT levels were observed in 36 patients, or 44 percent, with an average recovery time of eight weeks. Improvements in SGPT were reported to be temporary in the schisandra group because levels tended to rise again 6 to 12 weeks after treatment was discontinued. Relapse rates were highest (4669 percent) in this time among those with chronic persistent hepatitis, elderly patients, and in those receiving long courses of treatment with hepatotoxic drugs. Most patients responded to resumption of treatment with a return to their previously reduced SGPT levels.
These reports and other studies led to the development of the antihepatotoxic drug dimethyl-4,4'-dimethyoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarbonate (DDB) derived from schisandrin lignans. DDB promotes a marked improvement in liver functions, including lowering elevated SGPT levels, bilirubin, and an alpha-fetal protein that results in subjective improvement of patient symptoms. This drug is widely used for treating chronic viral- and drug-induced hepatitis in China.9
Adaptogenic Effects
Schisandra's traditional use as a tonifier in TCM led to research for this effect, predominantly in the former Soviet Union, where it was defined as an "adaptogen." Although generally not an accepted category of therapeutic substances in modern medicine, adaptogens are substances believed to reinforce the nonspecific resistance of the body against physical, chemical, or biological stressors. Primarily, they are considered to enhance the body's general physiological adaptive responses.10
Schisandra's use as an adaptogenic tonic has been the subject of numerous studies since the 1950s. There is a significant amount of evidence, in conjunction with its long-standing traditional use as a tonic, that it is effective in this role. The majority of this earlier adaptogenic research, however, is marred by poor study design and insufficient data.
The ability of an extract of the dried fruit to increase mental and physical activity in humans was reported in numerous studies conducted in the 1950s. In these studies, improvement was seen in activities that required concentration, coordination, and endurance. As an example, a study of telegraphists demonstrated that a dose of 5-10 mg/kg body weight schisandra was able to prevent tiredness and increase the correctness of telegrapahic transmission and reception by 22 percent.11
Other researchers reported the effect of schisandra on 59 airline flight attendants aged 2229. The effects of nonstop seven- to nine-hour flights, as measured by several stress parameters, were evaluated before and after the flights with and without treatment with 0.5 g schisandra extract. Control subjects displayed an increase in heart rate from 76 beats per minute (bpm) to 88 bpm and blood pressure from 112 to 119, while those administered the schisandra preparation exhibited no changes.12
Schisandra appears to be free of toxicity when administered orally within its recommended dosage range. Individuals with high gastric acidity or peptic ulcers may experience increased acidity.13 Those with abnormally high intracranial pressure or with epilepsy should avoid use.14 Based on the limited information available, schisandra should be avoided or used with caution by pregnant women.13,15
In one mouse study, the lignan schizandrol A was reported to significantly prolong sedative-induced sleeping times, enhance the sedative effects of drugs, and antagonize the stimulatory effects of amphetamines and caffeine on spontaneous motor activity.8
In the United States, schisandra is popularly used as a general tonic for decreasing fatigue, enhancing physical performance, and promoting endurance due to its effects and reputation as an adaptogen. In China it is widely used for various liver conditions. Among TCM practitioners, it is similarly used as a tonic and is also prescribed according to the principles of TCM.
Sidebars:
Schisandra: Structure/Function Claim
AHP Monographs Well Respected
Excerpt reprinted with permission from The American Herbal Pharmacopoeia and Therapeutic Compendium, a bimonthly series of peer-reviewed monographs. Complete monographs are available individually or by subscription and are published by the American Herbal Pharmacopoeia, Santa Cruz, Calif.
References
1. Bensky D, et al. Chinese herbal medicine: materia medica. Revised ed. Seattle: Eastland Press. 1993. 556 p.
2. Slanina J, et al. Isocratic high-performance liquid chromatography of dibenzocyclootadiene lignans from seeds of Schisandra chinensis Baill. Scrip Med 1995;68(8):335-42.
3. Yen K. The illustrated Chinese materia medica. Taipei: SMC, 1992. 383 p.
4. Bao TT, et al. A comparison of the pharmacologic actions of 7 constituents isolated from Fructus schizandrae. Chin Med J 1980;93(1):41-7.
5. Kubo S, et al. Effect of gomisin A (TJN-101) on liver regeneration. Planta Med 1992;58:489-92.
6. Yamada S, et al. Preventive effects of gomisin A: a lignan component of schisandra fruits on acetaminophen-induced hepatotoxicity in rats. Biochem Pharmacol 1993;46(6):1081-5.
7. Chang HM, But PH. Pharmacology and applications of Chinese materia medica. Vol. 1. Singapore: World Sci 1986. 773 p.
8. Liu GT. Pharmacological actions and clinical uses of Fructus schizandrae. In: Zhou J, Liu GT, Chen J, editors. Recent advances in Chinese herbal drugs-actions and uses. Beijing: Sci Press; 1991. p 100-11.
9. Wagner H. Immunostimulants and adaptogens from plants. In: Arnason JT, Mata R, Romeo JT, editors. Recent advances in phytochemistry: phytochemistry of medicinal plants. New York: Plenum; 1995. 364 p.
10. Brekhman H, Dardymov IV. New substances of plant origin which increase nonspecific resistance. Ann Rev Pharm 1969;9:419-30.
11. Lupandin AV, Lapaev II. Stimulative and tonic action of schizandra. Khabarovsk: Khabarovsk Book; 1981.
12. Sandberg F. Schisandrae fructus wuweizi. Gothenburg: 1993. 33 p.
13. Niu XY, et al. Metabolic fate of schizandrol A and its distribution in the rat brain determined by think layer chromatography. Acta Pharm Sin 1983;18(7):491-5.
14. Trifonova AT. Stimulation of labor activity using Schizandra chinensis. Obst Gyn 1954;4:19-22.
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