Niu Xi - Achyranthis bidentatae

Professional Data
 Pin Yin
Niu Xi
Radix Achyranthis bidentatae
 Introduction Back to Top
Radix Achyranthis Bidentatae is officially listed in the Chinese Pharmacopoeia as the dried root of Achyrantes bidentatae Bl (Fam. Amarathaceae). The drug is collected in winter when the aerial part is withered, removed from rootlet and soil, tied up in small bundles, sun-dried until externally wrinkled, fumigated with sulphur twice, cut evenly at the summit, and dried in the sun.
A. Bidentatae is mainly noted for its blood-stimulant, emmenagogue and "liver"- and "kidney"-tonifying effects, and its fortifying action on the muscles, tendons and bones.

 Western medical Back to Top
Anti-inflammatory, detoxicant. The herb is mainly prescribed in amenorrhea due to hemostasis, dysmenorrhea, irregular menstruation, injuries due to impact fractures, contusions and strains, lumbar and knee atrophy, contracture of limbs, hematemesis, epistaxis, hematuria due to gonorrhea, gingivitis, laryngitis, and carbuncle. Dizziness, headaches, blurred vision.

 Eastern medical Back to Top
  • Pattern: Clears damp heat lower burner. Invigorates blood. Tonifies and nourishes liver and kidneys.
  • Properties: Bitter, sour, neutral.
  • Channels entered: Liver, kidney.
 Chemical constituents Back to Top
Besides oleanolic acid from A. bidentata, some insect molting substances were also isolated from the roots of Achyranthes species. Ecdysterone and inokosterone were found in the root of A. bidentata. Oleanolic acid is a triterpene compound derived from oleanane and is widely distributed in herbal medicine. The insect molting substances ecdysterone and inokosterone are of steroid nature with a cholestane skeleton.

 Pharmacological actions Back to Top
Hematological effect

Radix A. Bidentatae markedly increased blood flow in rat hind limbs and had a vasodilatory effect.

Anti-inflammatory and Analgesic effects

The decoction reduced inflammation in rat paws that was induced by egg white and when administered the decoction exhibited analgesic action. Significant therapeutic effects were obtained against formaldehyde-induced swelling of rat paws.

Blood-pressure lowering effect

The injection of the aqueous extract elicited a prompt reduction in blood pressure. The hypotensive effect was reversible.

Actions on the Cardiovascular System

A definite inhibitory action on the isolated frog heart and on the anesthetized cat heart was exhibited by the alcohol extract of A. Bidentatae in vivo. A marked inhibitory action on the myocardium of anesthetized dogs was also achieved with the A. Bidentatae decoction. The herb directly dilated frog blood vessels; the intravenous injection of its decoction or alcohol extract to anesthetized dogs, cats, or rabbits caused transient hypotension, and in dogs, reduced kidney volume. Respiratory stimulation accompanied the hypotensive effect. Rapid development of tolerance to the hypotensive action, which was mainly attributed to histamine liberation and partly to cardiac depression and peripheral vasodilation, was not observed.

Oral administration of the A. bidentatae decoction to rabbits did not change the specific gravity of the whole blood but decreased blood viscosity as well as accelerating blood clotting.

Action on Protein Metabolism

(Extract)The ecdysones contained in Radix A. bidentatae had a strong protein anabolic action. The oral dose increased the incorporation of amino acids into the hepatic nuclei, mitochondria and microsomes 2 hours after medication. Its potency was similar to that of 4-chlorotestosterone. Simultaneously an increase in the anabolism of the kidneys was observed. Ecdysterone given for 60 days increased body onload="highlight();" weight and enhanced protein metabolism in the liver and kidneys. Examination of the liver tissue revealed meganuclear, binuclear, polynuclear and mitotic cells.

Action on Protein Anabolism

The ecdysones contained in A. Bidentatae had a strong protein anabolic action. A single oral dose or intraperitoneal injection of ecdysterone in mice increased the incorporation of amino acids into the hepatic nuclei, mitochondria, and microsomes 2 hours after medication. The action became stronger after 4 hours, and its potency was similar to that of 4-chlorotestosterone. Simultaneously, an increase of protein anabolism in the kidneys was observed; this activity returned to its original level after 4 hours. Meanwhile, protein anabolism was not increased in the spleen. A 4-chlorotestosterone-like activity, which promoted protein anabolism, was also present in the acellular system of the liver of animals given ecdysterone. Ecdysterone also promoted RNA synthesis in the hepatic nuclei and cytoplasms. In gradient centrifuge analysis of sugar, casting activity of the RNA of the treatment group was enhanced twofold relative to the control, suggesting that the facilatory effect of ecdysterone on protein anabolism was accompanied by the promotion of m-RNA synthesis. Ecdysterone given to weaned male young mice for 60 days quickly increased the animals body onload="highlight();" weight, and enhanced protein anabolism in the liver and kidneys. Examination of the liver tissue revealed meganuclear, binuclear, polynuclear and mitotic cells. The other ecdysones also promoted protein anabolism to various degrees. For example, cyasterone at a dose as small as 5 mg daily to mice produced marked effects similar to those of ecdysterone and was without any toxicity.

Diuretic Action

A mild diuretic action was demonstrated after intraveous injection of the decoction or alcohol extract of A. bidentatae.

Actions on the Intestinal Tract

The gastric motility in anesthetized dogs and in normal or anesthetized rabbits was slightly inhibited by intravenous injection of A. Bidentatae and so was the isolated intestinal tract of mice. But the herb had an excitatory effect on the intestinal tract of guinea pigs.


In mice given the intraperitoneal injection of 3H-ecdysterone, maximum radioactivity in the various organs was reached in 10 minutes after the drug was given; thereafter, a rapid decline was observed. The process was slower if the dose was administered by the intragastric route which gave lower drug concentrations in the liver, blood, kidney and other organs. It can be seen that absorption was faster and more complete with the intraperitoneal injection than with the intragastric route. In either route, however, the highest drug concentration was in the liver. Rapid appearance of the radioactivity was detected in the feces and urine after the intraperitoneal injection; this was slower after the oral dose. The fact that larger quantities of the drug were found in the feces than in the urine suggests that ecdysterone is mainly excreted via the liver-bile-intestinal tract.

Hepatic actions

Oleanolic acid was effective in the prevention of experimental liver damage induced by carbon tetrachloride (CCI4) in rats. Treatment with oleanolic acid markedly reduced the elevation of serum glutamic-pyruvic transaminase (GPT) and liver triglyceride levels in rats intoxicated with CCI4. The degeneration and necrosis of liver cells induced by CCI4 were significantly diminished with oleanolic acid treatment. Moreover, the glycogen content in the liver cells of the treated rats was increased, and the damaged mitochondrial and endoplasmic structures of liver cells were restored.

A number of esters, amides, or mixed amides of oleanolic acid were synthesized and tested for antiulcer activity. 3-Hemisuccinato-oleanolic acid morpholinide, 3hemisuccinato-oleanolic acid isopropylamide, and the mixed amide from oleanolic acid and succinic acid were the most active compounds in this series and were more effective than the known antiulcer agent carbenoxolone.

In addition, oleanolic acid inhibited the activation of Epstein-Barr virus induced by the tumor promotor 12-O-tetradecanoylphorbol 1 3-acetate (TPA) and the tumor promoting activity of TPA in mice. The inhibitory activity of oleanolic acid on tumor promotion by TPA was comparable to that of the known tumor promotion inhibitor retinoic acid.

Miscellaneous Actions

Though ecdysterone and the others did not effect the normal blood glucose, they reduced hyperglycemia elicited by glucagon, anti-insulin serum and dextran; they could also improve liver function, lower plasma cholesterol level, and shorten the larval period of silkworm.

 Clinical Studies Back to Top
Angina pectoris due to coronary heart disease

Guan Xin Huo Xue Tang: dan shen, chuan niu xi, 20g each; tao ren, hong hua, chi shao, 12g each; quan gua lou 15g; san qi powder, 1.5g; xie bai 6g; yan hu 3g. 212 cases of angina pectoris wre treated, and the total effective rate was 96%.

Cerebral thrombosis

tian ma 10g, chuan niu xi 15g, gou teng 15g, huang qin 15g, luo shi teng 15g, chuan xiong 15g, hong hua 15g, water decoction, for 10~15 courses. The formula was used to treat cerebral thrombosis, and the effective rate was about 85%.

Vascular migraine

chuan xiong, niu xi, 20g each; man jing zi, bai jiang can, 10g each; sheng shi jue ming 20g; sheng di 15g; ju hua 12g; water decoction. The formula usually took effect after 7 doses.

 References Back to Top

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