The polysaccharides composed of glucose and arabinose extracted from A. membranaceus var. mongholicus were reported to increase the immune response when administered i.p. to mice. Moreover, they also caused an increase in the amount of RNA in the spleen and a decrease in the incorporation of (3H)uridine into RNA. Similar effects on other reticuloendothelial tissues but no effect on thymus, heart, or brain RNA or on DNA metabolism was noted.

The homogeneous fraction of polysaccharides obtained by water extraction, consisting mainly of astragalan I and II, exhibits a wide spectrum of immunological effects on mice. By i.p. administration it increased the weight and cell number of mouse spleen, elevated the response of mouse spleen against sheep red blood cells, and stimulated phagocytic activity of peritoneal macrophages. The number of activated macrophages in the spleen of the treated animals was also increased. If the polysaccharide fraction was given i.v. or intragastrically, even at higher doses, the phagocytic function of peritoneal macrophages did not change significantly. Astragalan II decreased the alkaline RNase activity in liver and spleen of mice and had a smaller effect on acid RNase but no effect on serum RNase. The polysaccharide fraction also increased hepatic RNase inhibitor activity.

The natural killer cytotoxicity of lymphocyte effector cells was markedly enhanced when treated with partially purified human interferon-os or with extract of A. membranaceus. They stimulated each other: the natural killer cytotoxicity increased five to sixfold after treatment of effector cells with both agents.

Saponin astramembrannin I, at a dose of 10 mg/kg applied i.v., induced accumulation of cAMP in rabbit plasma. The increase in cAMP started after 30 min and reached a maximum in 0.5 4 h after a single injection. Saponin affected DNA biosynthesis in partially hepatectomized mice and increased incorporation of (3H) thymidine into regenerating mouse liver

The A. membranaceus decoction given to mice orally at a dose of 0.5 ml daily or on alternate days for 1-2 weeks increased the phagocytic activity of the reticuloendothelial system The phagocytic index was significantly increased even if the rehabilitation of the mouse reticuloendothelial system was disrupted by the injection of carbon particles prior to the administration of A. membranaceus. Concomitant use of rifampicine and G. lucidum Mixture (Radix Astragali, Radix Codonopsis Pilosulae, Ganoderma Lucidum) improved and regulated the suppressed immunologic function of mice. When used with antituberculous drugs, the mixture significantly decreased the mortality rate and prolonged the median survival time of tuberculous mice. These results are significantly better than that achieved with antituberculous drugs alone. G. lucidum Mixture also greatly enhanced the bactericidal function of the spleen It was shown in antiviral studies that either the oral doses or nose drops of the A. membranaceus decoction protected mice from infection of parainfluenza virus type I. Results from 28 experiments using 1299 mice in total showed that the effect of A. membranaceus resembled, by and large, those of the interferon mediator, tilorone, and bronchitis vaccine. Oral administration or nasal spray of this herb offered protection against the common cold in an epidemiological study involving 1000 subjects Though the herb was not itself an interferon inducer, it could promote the production of interferon by the mouse lung against parainfluenza virus type I and Newcastle disease virus In patients susceptible to common cold, administration of this herb for two weeks or two months enhanced the induction of interferon by peripheral white blood cells as compared with the premedication stage. Similar results were demonstrated in studies with mice. The induction of leukocytes to produce interferon in patients could be one of the antiviral mechanisms of A. membranaceus Addition of A. membranaceus to the culture of mouse renal cells increased their production of interferon in that the interferon titer was much higher in the A. membranaceus group than in the control group Two months of oral treatment with this herb in subjects susceptible to common cold greatly increased the levels of SIgA and IgG in the nasal secretion. Moreover, quantitative changes in the SIgA were found correlated with the severity of the common cold Tablets of the dried fluidextract of the whole plant given to 80 normal subjects by mouth greatly increased the IgM and IgE These results indicate that A. membranaceus promotes humoral immunity.

In comparison with the control, addition of the herb decoction to rat renal cell culture, whether before or after a challenge by follicular stomatitis virus, lowered the viral titer in the treated cells, indicating that A. membranaceus could inhibit the pathogenicity of virus on cell cultures. Further studies revealed that the inhibitory effect of A. membranaceus on viral multiplication is mediated by cells In addition, A. membranaceus enhanced the specific rosette formation of mouse lymphocytes on sheep red blood cells Atrophy of the immune tissues such as the spleen, thymus, and intestinal lymph nodes, as well as Leukopenia, all caused by the immunosuppressant, prednisolone, were antagonised by the polysaccharides of the herb. Concomitant injection of the polysaccharides with the allergen via the same route produced a pronounced adjuvant effect wherein the number of plaque-forming cells was increased

In 53 cases treated intramuscularly with A. membranaceus injection (1:1) 2 ml daily for a course of 1-2 weeks, the symptoms were improved and the WBC count increased to 4000-5000/mm3 or higher; 31 cases were followed-up for 1-2 months and 80% were found to have WBC count maintained higher than 4000/mm3

Antiinflammatory effects of astramembrannin I were demonstrated in rats. It inhibited the increase in vascular permeability induced by serotonin or histamine when given i.v. at a dose of 5 mg/kg or orally at a dose of 50 mg/kg. Oral administration of astramembrannin I caused a dose dependent reduction in carrageenan-induced edema of the hind paw of rats.

The A. membranaceus decoction had no significant effect on the isolated frog heart, but the ethanol extract enhanced the contractility and increased the contraction amplitude of the isolated frog or toad heart. Large doses, however, produced cardiac depression. Intraperitoneal injection of the herb 0.5 g/kg to dogs had no significant effect on the heart rate but produced, 3-4 hours later, inverted and biphasic T waves and slightly prolonged ST intervals Hypotension was elicited in rabbits, dogs or cats by the intravenous doses. Consecutive dosings resulted in tachyphylaxis. A longer hypotensive effect was produced by the intragastric doses (0.5-1.0 g/kg) The hypotensive constituent was earlier thought to be an alkaline substance ; However, recent studies found that the strength of the hypotensive action closely correlated with the amounts of y-aminobutyric acid in the Astragalus root. This substance was therefore considered to be the active hypotensive principle It is preliminarily held that the hypotensive mechanism is related to direct vasodilation, and that it has no significant connection with the vasomotor center, nerve ganglions, uscarinic receptors, and epinephrine and histamine release Other authors also reported that A. membranaceus produced vasodilation including that of the coronary arteries. Significant vasodilation of hind limbs of anesthetized dogs and cats was elicited by the intravenous dose of the A. membranaceus injection; the same effect was achieved on the renal blood vessels. Large doses, however, caused reflex renal vasoconstriction due to hypotension As with A. membranaceus y-aminobutyric acid at 10 g/kg (equivalent to 30 times the y-aminobutyric acid content in A. membranaceus ) resulted in similar vascular effect. Intra-arterial injection of small doses of A. membranaceus however, markedly decreased the vascular resistance of the hind limb, whereas -aminobutyric acid was inactive. It is obvious from these facts that the vasoactivity of A. membranaceus could not be totally attributed to y-aminobutyric acid

Hypotensive activity of astramembrannin I was observed after i.v. administration of 15 or 10 mg/kg to anesthetized cats or rats

A clinical effect of A. membranaceus in the treatment of chronic hepatitis was also reported. Elevated levels of serum GPT returned to normal in 1-2 months, and symptoms were relieved. Patients had a good appetite and a sense of wellbeing after treatment, without showing significant side effects. Experiments on animals with toxic liver damage induced by CC14 indicated that the root of A. membranaceus might protect the liver, prevent decrease of hepatic glycogen contents, and raise the levels of total serum protein and albumin

Phagocytosis of the reticuloendothelial cells of patients with chronic hepatitis was also stimulated, and cellular immunity was enhanced

Histochemical examination of the liver of mice dosed with A. membranaceus revealed increase of glycogen, and activation of lysosomal and tissue dehydrogenases In an experiment where the hepatic glycogen level was used as the criterion of therapeutic effect, oral administration of the 100% decoction 0.4 ml daily was found to protect the liver and to prevent the loss of hepatic glycogen in mice with acute toxic hepatitis induced by carbon tetrachloride given on the 8th experimental day

In 49 cases of chronic persisting hepatitis treated with the A. membranaceus injection, a marked effective rate of 61.2% and an aggregate effective rate of 85.7% were attained. Normalization of the GPT level was achieved in 80% of the responsive cases in 1-2 months

The addition of the 0.5% A. membranaceus to monolayer cultures of renal cells of the human embryo, hamster and mouse increased the number of living cells, caused vigorous cellular growth and doubled the life-span of these cells. A. membranaceus also delayed the natural ageing process of cultured human embryonic pulmonary diploid cells and markedly increased the maintenance time of the culture Electron microscopic examination of the human embryonic renal cells cultured in the nutrient medium containing A. membranaceus (the final concentration being 0.3-0.5%), revealed an increase in the myelomembranous changes in the lysosomal membrane on the fourth and seventh days; histochemical studies showed a marked increase in glycogen granules, acid phosphatase and succinic dehydrogenase These results suggested that A. membranaceus enhanced the physiological metabolism of cells. Daily intragastric administration of 0.5 ml of the decoction ofA. membranaceus var. mongholicus (1:0.33 g) 0.5 ml to mice for 10 or 14 days markedly increased the plasma cAMP. A more prominent effect was achieved from daily intragastric administration of the A. membranaceus extract obtained by cation exchange resins 0.2 ml (equivalent to 6 g of crude drug) for 14 days (10g). cAMP was also markedly increased in 80 normal subjects given tablets of the dried fluidextract of the herb

In addition, the A. membranaceus injection (1:1) given subcutaneously at 0.3 ml/day for 5 days markedly increased the total WBC count and polynuclear leukocytes One paper reported that A. membranaceus increased the hemoglobin in mice bearing U14 tumor

Studies on human subjects showed that A. membranaceus has a moderate diuretic action; it can increase the urine output and chloride excretion. The clinical dose of 0.2 g/kg increased urine output by 64% and sodium excretion by 14.5%. In rabbits, the orally administered decoction increased the urine output by 17.5%, while a 36% increase was obtained with the intraperitoneally administered ethanol extract Diuresis was produced by injection of A. membranaceus at 0.5 g(crude drug)/mg SC but not at 0.25 g/kg. In contrast, 1.0 g/kg of A. membranaceus decreased the urine output. The diuretic effect produced by a dose of 0.5 g/kg was equivalent to that obtained with 0.05 g/kg of aminophylline or 0.2 mg/kg of hydrochlorothiazide. No drug tolerance developed after 7 days of medication

Approximately 15 minutes after injection of A. membranaceus 0.5 g/kg IV to anesthetized dogs, micturation was briefly inhibited but 1-1.5 hours later urine output was markedly increased.

Administration of the A. membranaceus powder 4-5 g daily to rats for 3 days, prior to the production of nephrotoxic nephritis by injection of the rabbit anti-rat-kidney serum, markedly decreased proteinuria on the third day of the serum injection. Histological examination showed abatement of nephrosis. The antinephritis effect of the herb is thought to be related to the enhancement of metabolism and improvement of the systemic nutritional state Prescriptions containing large amounts of A. membranaceus used for the treatment of chronic nephritis in traditional Chinese medicine can also eliminate proteinuria

The 5% and 10% decoction of A. membranaceus markedly increased the tonicity, reduced the peristalsis, and increased the contraction amplitude of the rabbit intestinal tract in vivo, but they inhibited the isolated rabbit intestine and uterus It was, however, also reported that the A. membranaceus decoction inhibited the motility of both the in situ and isolated rabbit intestines. The extract of A. membranaceus var. mongholicus was shown to increase the contraction amplitude of the isolated small intestine of guinea pigs The A. membranaceus injection exerted a contracting action on the isolated rat uterus, with an efficacy equivalent to that of 0.0045 unit/ml of standard pituitrin

A paper reported that A. membranaceus produced estrogenic effects in mice by prolonging the estrous period (normally 1 day) to up to 10 days The herb had no effect on the blood glucose level The intravenous dose of the 1:1 A. membranaceus injection (1 g/kg) did not significantly affect the blood glucose level within 5 hours. Likewise, no significant hypoglycemic effect was achieved with the subcutaneous or intragastric dose (0.5 g/kg) of the injection in normal rats, or in rats with experimental hyperglycemia. However, the herb exhibited a tendency to increase the blood glucose level of animals with hypoglycemia induced by insulin

In vitro, A. membranaceus was shown to be active against Shigella shigae, Bacillus anthracis, Streptococcus hemolyticus, Streptococcus hemolyticus, Corynebacterium diphtheriae, Corynebacterium pseudodiphtheriae, Diplococcus pneumoniae, Staphylococcus aureus, Staphylococcus citreus, Staphylococcus albus, and Bacillus subtilis

A satisfactory prophylactic effect against common cold was achieved in 1000 subjects given A. membranaceus orally or as a nasal spray, or Decoction of Radix Astragali Crudae, Rhizoma Dioscoriae, Rhizoma Atractylodis Macrocephalae, Radix Rehmanniae Crudae, Pericarpium Citri Reticulatae, Poria, as evidenced by a decrease in the incidence of the disease and in the shortening of its course.

An injection prepared from the alcohol-precipitated decoction of A. membranaceus (1.0 g/ml) administered intramuscularly at 2 ml twice daily for a course of one month was employed to treat 73 cases. Marked improvement in the subjective symptoms, particularly the vigor and appetite, was obtained. The barium test performed in 36 cases revealed healing of duodenal ulcer in 22.2%, improvement in 48.1%, and ineffective in 29.7%; the corresponding percentages for gastric ulcer were 64, 18, and 18%.

Out of 43 cases of peptic ulcer treated with the Radix Astragali Decoction for Stomach Reinforcement for a course of 25 days, 22 cases (51.2%) were cured, 17 (39.5%) had improvement and 4 cases (9.3%) were unchanged.

Eighty-nine children with impaired absorption of the small intestine (with "splenic deficiency", rickets, or susceptibility to respiratory tract diseases) were given the Spleen-Invigorative Powder: Radix Codonopsis Pilosulae, Rhizoma Atractylodis Macrocephalae, Radix Glycyrrhizae 3 g daily for one month. The following therapeutic effects were documented: increase of xylose clearance in 70 cases (78.8%), and reduction in 19 cases (21.2%), marked improvement of the clinical symptoms, and marked decrease in the incidence rate, particularly that of the respiratory tract

Except those noted, all references come from Weng Weiliang, et al., Clinical Chinese materia medica, Henan Science & Technology Press, 1998