material of interest: dried root
known as ginsenosides, not less than 1.5% calculated as ginsenoside Rg1
(D-glucopytanosyl-6B-glucopyranosyl-20S-rpotopanaxatiol, relative molecular
Intrapenritoneal administration to rats of ginseng saponin fractions or the ginsenosides Rb1, Rb2, Rc, Rd, and Re elevated serum levels of adrenocorticotropic hormone (ACTH) and corticosterone. Pretreatment with dexamethasone, which blocks hypothalamus and pituitary functions, prevented ginseng saponin-mediated release of a CTH an dcorticosterone, and thereby demonstrated that the increase in serum corticosterone by ginseng occurs indirectly thrugh release of ACTH from the pituitary.
The immunomodulatory activity of ginseng appears to be at least partly responsible for its adaptogenic effect. Alcohol extracts of Radix Ginseng Stimulated phagocytosis in vitro, were mitogenic in cultured human lymphocytes, stimulated the production of interferon, and enhanced the activity of natural killer cells. Intraperitoneal administration of an extract of the drug to mice stimulate cell-meidated immunity against Semliki Foirest virus, elevated antibody levels against sheep red blood cells and natural killer cells, and stimulated the production of interferon.
Improvement in physical and mental performance has been observed in mice and rats after oral or intraperitoneal administration of the drug. Oral administration of ginseng saponin fractions to mice increased endurance and prolonged swimming time in swimming tests. However, two studies concluded that ginseng had no positive effects on the physical performance in mice and rats. The adaptogenic effects of Radix Ginseng are generally attributed to the ginsenosides. The ginsenosides have been shown to alter mechanisms of fueld homeostasis during prolonged exercise, by increasing the capacity of skeletal muscle to oxidize free fatty acids in preferenc to glucose for cellular energy production. Other constituents of Radix Ginseng, such as vanillic an dsalicylic acid, have also been reported to have "anti-fatigue" activity in rats. Furthermore, the antioxidant activity of ginseng was associated with both the ginsenosides and th eflavonoid constituents. The ginsenosides protected pulmonary vascular endothelium against free-radical-induced injury.
Mice given ginseng extract or ginsenosides Rb1 and Rg2 orally during passiveavoidance response tests showed an improvement in learning ability which was negtively influenced by stress, and rats showed improved retention of learned behaviour. Ginsenosides Rg1 and Rb1 are the active nootropic constituents of the drug, an dimprove memory and learning in normal as well as cognition-impaired animals. The mode of action involves an increase in the synthesis and release of acetylcholine, and a decreasse of brain serotonin levels. In cerebral and coronary blood vessels, extracts of Radix Ginseng produced vasodilatation, which improved brain and coronary blood flow. The vasodilatory activity of the ginsenosides appears to be primarily due to relaxation of vascular smooth muscles. The ginsenosides block the contricting effects of norepinephrine in isolated aorta strips, and inhibit the uptake of 45 Ca2+ in the membrane and sarcolemma of rabbit heart tissue. Inhibition of Ca2+ uptake in the muscle membrane contributes to the mechanism of vasodilatation.
A number of polypeptide and glycans isolated from Radix Ginseng, named GP and panaxans A-E, respectively, have demonstrated hypoglycaemic panaxans A and B, have been shown to stimulate hepatic glucose utilization by increasing the activity of glucose-6-phosphate 1-dehydrogenase, phosphorylase a, and phosphofructokinase. Panaxan A did not affect plasma insulin levels or insulin sensitivity, but panaxan B elevated the plasma insulin level by stimulating insulin secretion from pancreatic islets, and further enhanced inslulin sensitivity by increasing insulin binding to receptors. The panaxans are not activce after oral administration. Administration of GP (intravenously or subcutaneously) to mice or rats decreased blood glucose and liver glycogen levels. Radix Ginseng also contains a number of other constituents with hypoglycaemic activity. denosine, isolated from a water extract of Radix ginseng, enhanced lipogensesis and cyclic AMP accumulation of adipocytes, and some of the ginsenoosides inhibited ACTH-induced lipolysis, suppressed insulin-stimulated lipogenesis, and stimulated the release of insulin from cultured islets.
Subcutaneous administration of a ginseng extract enhanced the mating behaviour of male rats. The drug further stimulated spermatogenesis in rat, and rabbit testes, and increased the motility and survival of rabbit sperm outside the body.
Intragastric or intradermal administration of an ethanol extract of the drug to rats decreased histamine-, pentagastrin-, carbachol- and vagal stimulation- induced gastric secretion, and inhibited gastric ulcers induced by stress or by pyloric ligation.
Liver-protectant activity of ginseng has been demonstrated in in vitro and in vivo. Intraperitoneal administration of Radix Ginseng extracts to normal and dexamethasone-treated rats did not influence the blood chemistry of normal rats, but it decreased aspartate aminotransferase and alanine aminotransferase levels in dexamethasone-treated animals, thereby demonstrating a liver-protectant effects. However, another study demonstrated that an intraperitoneal injection of a methanol extract of Radix Ginseng had no protective activity against carbon tetrachloride-induced hepatotoxicity in rats.
Aqueous and standardized ginseng extracts were tested in a placebo-controlled, double-blind study for immunomodulatory actions. Sixty healthy volunteers were divided into three groups of 20 each and were given either a placebo or 100mg of aqueous ginseng extract or 100mg of standardized ginseng extract, every 12 hours for 8 weeks. Blood samples drawn from the volunteers revealed an increase in chemotaxis of polymorphonuclear leukocytes, the phagocytic index, and the total number of T3 and T4 lymphocytes after 4 and 8 weeks of ginseng therapy, as compared with the placebo group0. The group receiving the standardized extract also increased their T4:T8 ratio and the activity of natural killer cells. The conclusion of this study was that ginseng extract stimulated the immune system in humans, and that the standardized extract was more effective than the aqueous extract.
and laboratory test interactions
mutagenesis, impairment of fertility
On the basis of Radix Ginseng's long use, and the relative unfrequency of significant demonstrable side-effects, it has been concluded that the use of Radix Ginseng is not associated with serious adverse effects if taken at the recommended dose. However, in Siegel's open study of 133 patients ingesting large quantities, ginseng was reported to result in hypertension, nervousness, irritability, diarrhoea, skin eruptions, and insomnia, which were collectively called ginseng abuse syndrome (GAS). Critical analysis of this report has shown that there were no controls or analyses to determine the type of giseng being ingested or the constituents of the preparation taken, and that some of the amounts ingested were clearly excessive (as much as 15g per day, where the recommended daily dose is 0.5-2g). When the dose was decreased to 1.7g/day the symptoms of the "syndrome" were rare. Thus the only conclusion that can be validly extracted from the Siegel study is that the excessive and uncontrolled intake of ginseng products hsould be avoided. One case of gisneng-associated cerebral arteritis has been reported in a patient consuming a high dose of an ethanol extract of ginseng root (approximately 6g in one dose). HOwever, again the type an dquantity of ginseng extract were not reported. Two cases of mydriasis and distrubance in accommodation, as well as dizziness have been reported after ingestion of large doses (3-9g) of an unspecified type of ginseng preparation.
Estrogenic-like side-effects have been reported in both premenopausal and postmenopausal women following th euse of ginseng. Seven cases of mastalgia and one caseof vaginal bleeding in a postmenopausal woman were reported after ingestion of unspecified ginseng products. An increased libido in premenopausal women has also been reported. Specific studies on the possible hormonal side-effects of gisneng have been carried out with a standardized ginseng extract. Under physiological conditions, there is no interaction of the gineng extract with either cytosolic estrogen receptors isolated from mature rat uterus or progesterone receptors from human myometrium. Furthermore, clinical studies have demonstrated that a standardized ginseng extract does not cause a change in male and female hormonal status.