General Introduction
Schisandra, also known as Schizandra, and formally named Schisandra chinensis, is an indigenous plant in China, Korea and Russia. For its uses within the context of various culturally based systems of medicine, Schisandra is valued for its ability to help the body manage the effects of stress, to enhance performance, and withstand adverse conditions. In traditional Chinese medicine, it is used to increase the production of bodily fluids, and for inflammation, coughs, skin problems, and sleep problems. Recent uses in China include its use for immune system modulation and hepatic protection. In botanical medicine traditions from around the world, certain herbs are in a category of functional use called “adaptogenic”, meaning that the herb has the reputation of helping the body to resist damage from physical and mental stressors. In clinical and healing settings, Schisandra is used for both preventing harm from stress and for treating the consequences of stress, as part of an overall rejuvenation therapy to revitalize bodily functions. Russian medicine values the use of schisandra for its adaptogenic properties that affect physical and mental performance; these include increases in strength, endurance, and better coordination; and improved concentration and attention. This may be a direct example of benefit of its antioxidant properties, as validated by research. 

Chemical Composition
The fruit and seeds of Schisandra plants contain large amounts of lignan compounds, which are phenols, a large group of plant constituents that are aromatic alcohols (Pengelly, 2004:15). Ligans are dimeric, made up of two simple identical molecules, with phenylpropane (C6C3) components connected to their side chains at the carbon 8 positions to make three-dimensional networks (Pengelly, 2004:20). In the species S. chinensis the principal pharmacological active compounds are thought to be the dibenzo[a,c]cyclooctadiene lignans, these lignans can be isolated from the unhydrolyzed fraction of the seed oil (Upton, 1999:6). Forty lignans have been identified, the greatest number of lignans are Schisandrol A (up to 5.17%) and Schisandrin B or y-schisandrin (up to 5.00%). Other primary lignans are Schisandrin A or deoxyschisandrin, Schisandrol B also known as Gomisin A due to different nomenclature used by Japanese researchers, Gomisin N, Schisantherin A and B (Zhu, 1998:654; Upton, 1999:6). Schisandra also contains volatile oil constituents, glycosides and organic acids (Bensky et al, 2004:861).

Different chemical structures of Schisandrin A, B & C
Differences in chemical structure result in different actions of the constituents, the presence of the methylenedioxy group, seen Schisandrin B and C, significantly increases the hepatoprotective effect. Whereas the presence of the hydroxy group at C-7 seen in Schisandrin A results in a decreased hepatoprotective effect (Upton, 1999:6). A study randomly pretreated mice with Schisandrin A, B or C intragastrically at a daily dose of 1mmol/kg for three days before administering an oral dose of Carbon Tetrachloride (CCI4) at 0.1mL/kg. Hepatic tissue samples were analyzed and levels of plasma alanine aminotransferase (ALT) and hepatic mitochondrial reduced glutathione (GSH) recorded (Ip, Ma, Che & Ko, 1997:317). 

Researches found that pretreatment with schisandrin B and C completely prevented CCI4 hepatotoxicity evident by significant decreases in plasma ALT activity increases in the hepatic mitochondrial GSH levels and glutathione reductase activity. On the contrary pretreatment  with Schisandrin A offered no protection evident by no change in ALT or GSH levels. Intoxication by CCI4 leads to increased oxidative stress and for cell survival mitochondrial glutathione redox is essential. Researchers concluded that hepatoprotection given by Schisandrin B and C was shown by increases in mitochondrial GSH levels stimulated by the methylenedioxy group of the dibenzocyclooctadiene skeleton of Schisandrin (Ip et al, 1997:319).

Indications in TCM(Traditional Chinese Medicine)
1. Chronic cough and dyspnea of deficiency type
It is an important herb for chronic cough and dyspnea of deficiency type due to lung and kidney deficiency. Because it is sour and sweet, it can astringe lung to relieve cough and dyspnea, tonify lung qi and nourish kidney yin. For chronic cough due to lung deficiency, it could be decocted in plaster, or sliced singly, or combined with lung-astringing and cough-relieving herbs. For cough, shortness of breath, fatigue and mental fatigue, it is combined with qi tonics and cough-relieving herbs. For instance, it is used with Ren Shen, Huang Qi, and Zi Wan in the formula Bu Fei Tang from Yong Lei Qian Fang (Yongleiqian’s Prescription). For cough and dyspnea due to both lung and kidney deficiency, it is combined with lung and kidney-tonifying herbs. For instance, it is used with Shan Zhu Yu, Shu Di Huang, and Shan Yao in the formula Du Qi Wan from Yi Zong Ji Ren Bian (Self-tasked Book of Medicine). It is good at astringing lung to relieve cough, but it is also indicated for cough and dyspnea due to fluid retention when combined with lung-warming and fluid-retention-removing herbs. For instance, it is used with Xi Xin and Gan Jiang in the formula Ling Gan Wu Wei Jiang Xin Tang from Jin Kui Yao Lue.  

2. Chronic diarrhea
It can astringe intestines to stop diarrhea. For chronic diarrhea due to spleen deficiency, it is combined with herbs of tonifying spleen, draining dampness, warming the middle, and astringing intestines, such as Bai Zhu, Sha Ren and Rou Dou Kou. It is combined with Rou Dou Kou and Chi Shi Zhi in the formula Dou Kou Yin from Shi Yi De Xiao Fang. For chronic diarrhea due to deficiency cold of kidney and spleen, it is combined with yang-warming and cold-dispersing herbs. For instance, it is used with Bu Gu Zhi, Rou Dou Kou and Wu Zhu Yu in the formula Si Shen Wan from Nei Ke Zhai Yao.

3. Seminal emission and spermatorrhea
It can tonify kidney, astringe essence and relieve emission, so it is a usual herb for seminal emission and spermatorrhea caused by insecurity of essence gate due to kidney deficiency. It could be decocted into plaster singly, or combined with kidney-warming and essence-astringing herbs. For instance, it is used with Sang Piao Xiao, Fu Zi and Long Gu in the formula Sang Piao Xiao Wan from Shi Yi De Xiao Fang. 

4. Spontaneous sweating, night sweat
It is a common herb for sweating of deficieney, because it can tonify lung and heart qi, strengthen superficial to check sweating. For spontaneous sweating due to qi deficiency, it is combined with qi tonics, such as Ren Shen. For night sweat due to yin deficiency, it is combined with yin tonics. For instance, it is used with Shu Di Huang, Shan Zhu Yu and Mai Dong in the formula Mai Wei Di Huang Wan from Yi Ji.

5. Thirst due to fluid injury, diabetes
It can nourish yin to relieve thirst, and tonify qi to improve the producing of yin fluid. For thirst and sweating due to qi and yin injured by heat, it is combined with qi and yin tonics. For instance, it is used with Ren Shen and Mai Dong in the formula Sheng Mai San from Nei Wai Shang Bian Huo Lun. For diabetes, which manifests as thirst and desire for drinking and is caused by internal heat due to yin deficiency, it is combined with heat-clearing, yin-nourishing and fluid-producing herbs. For instance, it is used with Shan Yao, Zhi Mu, Tian Hua Fen and Huang Qi in the formula Yu Ye Tang from Yi Xue Zhong Zhong Can Xi Lu.

Modern Researches
1. Anti-stress and adaptogenic properties
One study showed benefit in the use of schisandra for a human subject who was exhausted by mental work . Its use has also been studied in noticing its effects on EEG readings from rabbits experiencing acute fatigue. A review article stated there is good scientific evidence of Schisandra’s ability to increase endurance and mental performance in patients with fatigue and weakness . Race horses and polo horses given standardized extracts of schisandra fruit (48g) demonstrated increased overall performance and reduced fatigue. This was measured by a lowered increase in heart rate and a faster recovery of normal breathing after the race ended. This next study was designed to test the effect of Schisandra taken over a period of time. By the tenth day of oral administration of Schisandra tincture, male albino mice showed a statistically significant increase in time running on a treadbane. Schisandra tincture increased the swimming time of these male albino mice by 135 % – 159% in a test of swimming “to the limit”. 

2. Exercise performance
In a study using mice, a combination botanical product containing Schisandra increased swimming duration and improved tolerance to oxygen deficiency. A study using male rats showed that high-intensity training, strenuous exercise and experimental navigation can suppress the pituitary-testis axis and increase blood glucose levels. After intragastric administration of Schisandra fruits, the male rats had lower blood glucose levels and experienced protection of the pituitary-testis axis via normal levels of serum t-estosterone. Another study using male rats investigated the effects of schisandra on the function of the pituitary-adrenal cortex axis, the gonadal axis and carbohydrate metabolism as the rats were subjected to experimental chronic psychological stress, navigation and strenuous exercise. The male rats in the group that received Schisandra had lower levels of blood sugar and corticosterone. The Schisandra group also showed that the structure of the adrenal cortex was protected, as revealed by examination after excision. 

3. Schisandra Strengthens the Liver
Schisandra potentiates glutathione-Recent studies on laboratory animals show that schisandra increases glutathione levels, and provides:
-protection against brain damage, 
-enhanced immunity, 
-protection against the formation of cellular peroxides, 
-protection against cardiovascular disorders, 
– protection against toxins in the liver.

What is glutathione?
Glutathione is the major antioxidant found in almost every cell that protects it from free radicals. Antioxidants give up an electron to stop oxidation. They play a key role in neutralizing the estimated 10,000 “oxidative hits” each cell suffers a day. In other words, antioxidants are able to destroy free radicals in body cells before they can attack DNA or cause lipids to oxidize, resulting in cellular death and/or mutation. If glutathione is in short supply, free radicals can overwhelm the cell, and consequently disease and illness sets in. 

Free radicals are generated in the mitochondria—the powerhouse of each cell. They are unstable molecules that are missing an electron, and frantically bump into and damage other molecules in an effort to replace their lost electron. It is impossible to be alive and not have some oxidative damage, because free radicals are produced by normal processes in the body (like the release of adrenaline), and from environmental sources such as ultraviolet radiation, tobacco smoke, food additives, foods that have been fried in oil that’s been used over and over again (typical in many fast-food restaurants), and other pollutants. Once free radicals are released, they multiply geometrically in chain reactions, unless they are stopped by antioxidants. Antioxidants not only protect living tissue, but they repair the damage of oxidation. Glutathione also has the ability to recycle other antioxidants such as vitamin C and vitamin E, keeping them in their active state.

Glutathione helps the body get rid of toxins and pollutants
It forms a soluble compound with a toxin that can then be excreted through bodily waste. Many d-rug metabolites and heavy metals are disposed of in this way. Since the liver and kidneys have the greatest exposure to toxins, they contain high levels of glutathione.

Glutathione helps regulate the cell’s vital functions
Glutathione plays a crucial role in maintaining a normal balance between oxidation and antioxidation, (or free radicals and antioxidants). This, in turn, regulates many of the cell’s vital functions, such as the synthesis and repair of DNA, the synthesis of proteins, and the activation and regulation of enzymes. Supports strong immune response Glutathione is required in many of the intricate steps needed to carry out an immune response. For instance, it is used by lymphocytes to multiply in order to develop a strong immune response, and for killer T-cells to fight harmful cells such as cance-r cells or cells infected with viruses. The importance of glutathione cannot be emphasized enough. It performs multiple tasks, as indicated, and when you start looking at each system or organ closely, the necessity for glutathione becomes increasingly evident. 

4. Schisandra enhances cognitive function
Schisandra is one of the major herbs almost always used in Chinese mind tonic formulations. It has traditionally been used to treat mental and emotional illness and improve mental clarity, concentration, and coordination, reduce forgetfulness, irritability, nervous exhaustion, stress, depression, and anxiety. 

According to new research, schisandra shows potential as a protectant against brain damage. An in vitro study at the College of Pharmacy and Research Institute of Pharmaceutical Science, Seoul National University, Korea examined the results of schisandra extract on rodent brain cells and found 1) an improvement in the glutathione defense system, 2) an increase in the level of glutathione, and 3) an inhibition in the formation of cellular peroxide (a free radical). The researchers concluded that schisandra is a potential therapeutic aid against oxidative neuronal damage. A study at the Department of Biochemistry, Hong Kong University of Science & Technology, China, found that schisandra enhances cognitive function in mice, and protects the liver against toxicity from tacrine (an acetylcholinesterase inhibitor used for Alzheimer’s disease), leading the investigators to believe that schisandra may protect Alzheimer’s patients from the liver toxicity associated with taking tacrine. 

Safety of schisandra
Schisandra is very safe when used as directed. However, it should not be used during pregnancy or nursing, or in conjunction with d-rugs that cause drowsiness. Consult with your health practitioner before using schisandra if you have seizure disorders or high blood pressure. Schisandra is a safe, potent antioxidant with a number of significant therapeutic effects. Numerous scientific studies have validated the historical use of the herb, in particular as an adaptogen, liver protector, cardiovascular protector, brain protector and cognitive enhancer. Schisandra contains a complex mixture of constituents that not only complement each other, but potentiate each other and glutathione. It is definitely a nutritional supplement worth adding to your arsenal of antioxidants.