Plant Part Used
Root.
Active Constituents
Isoflavones, triterpenoids, saponins, including astragalosides I through VIII. (1) , (2)
[span class=alert]This section is a list of chemical entities identified in this dietary supplement to possess pharmacological activity. This list does not imply that other, yet unidentified, constituents do not influence the pharmacological activity of this dietary supplement nor does it imply that any one constituent possesses greater influence on the overall pharmacological effect of this dietary supplement.[/span]
Introduction
Astragalus has been valued by the Chinese for centuries for its immune-enhancing and adaptogenic properties. As an adaptogen, it may modify and improve the body’s response to stress through action on the adrenal cortex.(2),(3) Experiments have reported that Astragalus improves immunity and promotes regeneration of cells in the bronchi after viral infection.(4) Astragalus can be safely taken for months without the risk of suppressing immunologic function.
Interactions and Depletions
Interactions
Dosage Info
Dosage Range
250-500mg (standardized extract), 4 times a day.
Dried Root: 2-6 grams daily. (6)
Fluid Extract: 4 to 12 milliliters daily. (7)
Most Common Dosage
250mg (standardized extract), 4 times a day.
Dried Root: 2 grams daily.
Fluid Extract: 4 milliliters daily.
Standardization
[span class=doc]Standardization represents the complete body of information and controls that serve to enhance the batch to batch consistency of a botanical product, including but not limited to the presence of a marker compound at a defined level or within a defined range.[/span]
The most current available medical and scientific literature indicates that this dietary supplement should be standardized to a minimum of 0.4% 4’-hydroxy‑3′-methoxyisoflavone 7‑sug.
Uses
Frequently Reported Uses
- Adaptogen, Tonic
- Adjunctive Support In Chemotherapy And Radiation
- Immune enhancement
- Stamina
- Oxygen Deprivation Of Tissues
- Endurance
Other Reported Uses
- Anti-Cancer Agent
- Antiviral
- Peripheral Vascular Disease
Toxicities & Precautions
General
No known toxicity. (8)
Pregnancy/ Breast Feeding
If pregnant or nursing, consult a physician before use.
Age Limitations
Do not use in children under 2 years of age unless recommended by a physician.
Pharmacology
Immune modulation/Anticancer activity
The triterpenoids and saponins are structures similar to steroid hormones and precursors that act on the adrenal cortex, affecting the hypothalamus-adrenal-pituitary axis. Astragalus has been reported in laboratory and human studies to improve immunity.(25) Injections of Astragalus polysaccharides are reported in several clinical studies to improve immune function.(26),(27),(28) The polysaccharides contained in Astragalus relate to the improvement in natural killer (NK) cells and T-cell function, as well as interferon production by the immune system.(7) Studies have reported that administration of Astragalus for 1 month increased phagocytosis by spleen cells, decreased T-suppressor cell function and improved T-killer cell function.(7) Astragalus enhances the effects of interferon and may act not only to improve resistance to colds but decrease the duration of a cold.(8) A phase 0, double-blind, repeated within subject, randomized pilot study found that CD25 expression on T cells was significantly enhanced when an Astragalus preparation was administered orally.(29) A small clinical study in China found in asthmatic patients that Astragalus administration increased the expression of T-bet mRNA and Th1 cytokines such as IFN-Y, and might reverse the Th2 predominant status, helping to balance immunity in these compromised individuals.(30) Another small clinical study found that Astragalus administration improved cellular immunity after serious abdominal trauma.(31)
Astragalus is reported in laboratory studies to be effective against a variety of cancer cell lines, including gastric, urinary, lung.(32),(33)
A recent laboratory animal study reported that Astragalus root extract produced a significantly lower incidence of urinary bladder carcinoma in mice treated with a known carcinogen (N-butyl-N’-butanolnitrosoamine). These results suggest that the Astragalus extract exerts an anticarcinogenic effect in carcinogen-treated mice through activation of cytotoxic activity and the production of cytokines.(9) There is a predominance of Th2 cytokines in lung cancer patients which is associated with tumor progression. A study found that with the administration of Astragalus to lung cancer patients there was a reversal of the Th2 cytokine status.(10) Astragalus membranaceus has been used to decrease the side effects of antineoplastic drugs and radiation because of its immunomodulating effects.(34) Astragalus was also reported to decrease cyclophosphamide-induced immune suppression,(7),(22),(23) with one conflicting report.(24) Astragalus was also found to improve immune parameters in patients surgically treated for esophageal cancer.(35)
Antiviral/Antibacterial activity
Using an in vitro study, Astragalus root extract was reported to inhibit the RNA replication of the coxsackie B-3 virus (CVB3) in a viral myocarditis model.(14) Another in vitro study reported that Astragalus inhibited Ca2+ influx across the myocardial plasma membrane and coxsackie virus B3(CVB3)-RNA replication in cultured neonatal rat heart cells infected with the coxsackie B-3 virus.(15) The authors suggested that Astragalus may exert the effects of decreasing the secondary Ca2+ damages, improving abnormal myocardial electric activity, and inhibiting replication of coxsackie B3-RNA in myocardium, making it a potential therapeutic choice in patients affected with viral myocarditis. Use of Astragalus in patients with viral myocarditis may also be rational therapy due to the improvement of cellular immunity.(16)
A laboratory study found that Astragalus root extract has protective effects on polymicrobial sepsis in mice, with the mechanisms of action involving anti-inflammation and upregulation of the protein C (PC) pathway.(36)
Cardioprotective activity
Astragalus has long been used in Traditional Chinese Medicine as a cardiotonic agent. A study of left ventricular function and oxygen free radical (OFR) in 43 patients with acute myocardial infarction less than 36 hours old was reported.(17) The results showed that Astragalus strengthened the left ventricular function and had an effect of anti-OFR. After administration of Astragalus a significant difference between controls was seen. The ratio of pre-ejection period/left ventricular ejection time (PEP/LVET) was decreased, the superoxide dismutase (SOD) activity of red blood cell was increased, and the lipid peroxidation (LPO) content of plasma was reduced. The authors suggested that the anti-OFR effect of AM was one of the mechanisms of its cardiotonic action.
Another study reported the action on left ventricular function of Astragalus in 20 patients with angina pectoris.(18) Results showed that cardiac output increased from 5.09 +/- 0.21 to 5.95 +/- 0.18 L/min 2 weeks after AM was administered and no improvement of left ventricular diastolic function appeared. Adenosine triphosphatase activity was not inhibited by using Astragalus in the study, which seems to be different than the mechanism of digitalis.
Of interest is a recent Chinese study that reports on the use of Astragalus root having therapeutic effects on sodium and water retention in aortocaval fistula-induced heart failure in laboratory animals.(19) The authors concluded that the mechanisms of this effect might be the improvement of cardiac and renal functions, partly correction of abnormal mRNA expressions of AVP system and AQP2, and amelioration of blunted renal response to ANP.
Another recent animal study reported that a glucoside extracted from Astragalus root may be used after cholinergic crisis in the treatment of severe cardiac complications with severe organophosphate intoxication.(20) Prolongation of the Q-T interval and changing of the T wave configuration were significantly mitigated in the Astragalus treated animals along with a minimization and postponement of arrhythmias. Moreover, muscular fasciculation and fibrillation, seizures and secretion in the respiratory tract were also significantly reduced by Astragalus treatment.
Other activity
Other uses of Astragalus include possible improvement of impaired memory acquisition as well as the alcohol-elicited deficit of memory retrieval.(21) A laboratory study found that Astragalus protected endothelium-dependent relaxation against the acute injury from homocysteine through nitric oxide regulatory pathways, supporting the use of Astragalus as an antioxidant.(37)
Astragalus is also claimed to protect against cellular damage in the liver,(8),(11) help with oxygenation of the heart and cerebrovascular tissue and improve stamina and endurance.(12),(13)
A combination of Astragalus root and Salvia root was reported in a clinical study to be effective against fatigue associated with chronic fatigue.(38)
A small human study found that Astragalus root induces naturesis in healthy men, attributed to enhanced renal responses to endogenous atrial naturetic peptide (ANP).(39) A clinical report found that Astragalus use in a patient with idiopathic membranous nephropathy had improved clinical course, which degraded again when Astragalus was discontinued.(40)
Laboratory studies have reported that Astragalus root polysaccharides have insulin-sensitizing and hypoglycemic activities in type 2 diabetic (T2DM) rats.(41) Astragalus polysaccharides enhanced adaptive capacity of the endoplasmic reticulum and promoted insulin signaling by the inhibition of the expression and activity of protein tyrosine phosphatase 1B (PTP1B). The anti-obesity effect and hypolipidemia effects of Astragalus were due partly to decreasing the leptin resistance, which would positively couple with the normalization of plasma insulin levels.
References
- Hou YD, et al. Study on the Biologically Active Constituents of Astragalus Membranaceus. Chung Hsi I Chieh Ho Tsa Chih. Jul1984;4(7):420-24.
- He K, et al. Recent Development of Chemical Studies on Some Medicinal Plants of Astragalus spp. Yaoxue Xuebao. 1988;23:873.
- View Abstract: Zhao TH. Positive Modulating Action of Shengmaisan with Astragalus membranaceus on Anti-tumor Activity of LAK Cells. Zhongguo Zhong Xi Yi Jie He Za Zhi. Aug1993;13(8):471.
- Chang H, et al. Pharmacology and Application of Chinese Materia Medica. Singapore: Chinese University of Hong Kong, World Scientific. 1987:4.
- PDR for Herbal Medicines, 2nd edition. Montvale, NJ: Medical Economics Company; 2000:56.
- Leung A, et al. Encyclopedia of Common Natural Ingredients Used in Foods, Drugs, and Cosmetics. New York: Wiley-Interscience Publication; 1996:50-53.
- View Abstract: Chu DT, et al. Immune Restoration of Local Xenogeneic Graft-versus-host Reaction in Cancer Patients in In-vitro and Reversal of Cyclophosphamide-induced Immune Suppression in the Rat in Vivo by Fractionated Astragalus membranaceus. Chung Hsi I Chieh Ho Tsa Chih. Jun1989;9:351-54.
- Geng CS, et al. Advances in Immuno-pharmacological Studies on Astragalus membranaceus. Chung Hsi I Chieh Ho Tsa Chih. 1986;6(1):62-64.
- View Abstract: Kurashige S, Akuzawa Y, Endo F. Effects of astragali radix extract on carcinogenesis, cytokine production, and cytotoxicity in mice treated with a carcinogen, N-butyl-N’-butanolnitrosoamine. Cancer Invest. 1999;17(1):30-5.
- View Abstract: Wei H, Sun R, Xiao W, et al. Traditional Chinese medicine Astragalus reverses predominance of Th2 cytokines and their up-stream transcript factors in lung cancer patients. Oncol Rep. Sep2003;10(5):1507-12.
- View Abstract: Zhang YD, et al. Effects of Astragalus (ASI, SK) on Experimental Liver Injury. Yao Hsueh Hsueh Pao. 1992;27(6):401-06.
- View Abstract: Shi HM, et al. Intervention of Lidocaine and Astragalus membranaceus on Ventricular Late Potentials. Zhongguo Zhong Xi Yi Jie He Za Zhi. Oct1994;14(10):598-600.
- Griga IV. Effect of a Summary Preparation of Astragalus cicer on the Blood Pressure of Rats with Renal Hypertension and on the Oxygen Consumption by the Tissues. Farm Zh. 1977;6:64-66.
- View Abstract: Peng T, Yang Y, Riesemann H, et al. The Inhibitory Effect of Astragalus membranaceus on Coxsackie B-3 Virus RNA Replication. Chin Med Sci J. Sep1995;10(3):146-50.
- View Abstract: Guo Q, Peng TQ, Yang YZ. Effect of Astragalus membranaceus on Ca2+ Influx and Coxsackie Virus B3 RNA Replication in Cultured Neonatal Rat Heart Cells. Chung Kuo Chung Hsi I Chieh Ho Tsa Chih. Aug1995;15(8):483-5.
- View Abstract: Huang ZQ, Qin NP, Ye W. Effect of Astragalus membranaceus on T-lymphocyte Subsets in Patients with Viral Myocarditis. Chung Kuo Chung Hsi I Chieh Ho Tsa Chih. Jun1995;15(6):328-30.
- View Abstract: Chen LX, Liao JX, Guo WQ. Effects of Astragalus membranaceus on Left Ventricular Function and Oxygen Free Radical in Acute Myocardial Infarction Patients and Mechanism of Its Cardiotonic Action. Chung Kuo Chung Hsi I Chieh Ho Tsa Chih. Mar1995;15(3):141-3.
- View Abstract: Lei ZY, Qin H, Liao JZ. Action of Astragalus membranaceus on Left Ventricular Function of Angina Pectoris. Chung Kuo Chung Hsi I Chieh Ho Tsa Chih. Apr1994;14(4):199-202,195.
- View Abstract: Ma J, Peng A, Lin S. Mechanisms of the Therapeutic Effect of Astragalus membranaceus on Sodium and Water Retention in Experimental Heart Failure. Chin Med J. England. Jan1998;111(1):17-23.
- View Abstract: Li Y, Liu X, Xue SZ. Antidotal Effect of Glucoside Extracted from Astragalus membranaceus on Dimethoate Intoxication in Guinea Pigs. Med Lav. 1998;89(Suppl 2):S136-41.
- View Abstract: Hong GX, Qin WC, Huang LS. Memory-improving Effect of Aqueous Extract of Astragalus membranaceus (Fisch.) Bge. Chung Kuo Chung Yao Tsa Chih. Nov1994;19(11):687-8,704.
- View Abstract: Chu DT, et al. Immunotherapy with Chinese Medicinal Herbs. II. Reversal of Cyclophosphamide-induced Immune Suppression by Administration of Fractionated Astragalus membranaceus in Vivo. J Clin Lab Immunol. 1988;25(3):125-29.
- View Abstract: Zhao KS, et al. Enhancement of the Immune Response in Mice by Astragalus membranaceus Extracts. Immunopharmacology. 1990;20(3):225-33.
- View Abstract: Khoo KS, et al. Extract of Astragalus membranaceus and Ligustrum lucidum Does Not Prevent Cyclophosphamide-induced Myelosuppression. Singapore Med J. Aug1995;36(4):387-90.
- Cho WC, Leung KN. In vitro and in vivo immunomodulating and immunorestorative effects of Astragalus membranaceus. J Ethnopharmacol. 15 Aug 2007 ;113(1):132-141. Epub 2007 May 31.
- Yang Y, Wang LD, Chen ZB. [Effects of Astragalus membranaceus on TH cell subset function in children with recurrent tonsillitis] Zhongguo Dang Dai Er Ke Za Zhi. Oct 2006;8(5):376-378. Chinese.
- Li SM, Yan JX, Yang L. [Effects of Astragalus injection on renal tubular function in patients with IgA nephropathy] Zhongguo Zhong Xi Yi Jie He Za Zhi. 2006 Jun;26(6):504-507. Chinese.
- Cai XY, Xu YL, Lin XJ. [Effects of radix Astragali injection on apoptosis of lymphocytes and immune function in patients with systemic lupus erythematosus] Zhongguo Zhong Xi Yi Jie He Za Zhi. May 2006;26(5):443-445. Chinese.
- Zwickey H, Brush J, Iacullo CM, et al. The effect of Echinacea purpurea, Astragalus membranaceus and Glycyrrhiza glabra on CD25 expression in humans: a pilot study. Phytother Res. Nov 2007;21(11):1109-1112.
- Wang G, Liu CT, Wang ZL, Yan CL, Luo FM, Wang L, Li TQ. Effects of Astragalus membranaceus in promoting T-helper cell type 1 polarization and interferon-gamma production by up-regulating T-bet expression in patients with asthma. Chin J Integr Med. Dec 2006;12(4):262-267.
- Wu J, Wang YX, Su WL, Zhu WX, Lu JW, Li ZK. Effect of Astragalus injection on serious abdominal traumatic patients’ cellular immunity. Chin J Integr Med. Mar 2006;12(1):29-31.
- Na D, Liu FN, Miao ZF, Du ZM, Xu HM. Astragalus extract inhibits destruction of gastric cancer cells to mesothelial cells by anti-apoptosis. World J Gastroenterol. 7 Feb 2009 ;15(5):570-577.
- Cho WC, Leung KN. In vitro and in vivo anti-tumor effects of Astragalus membranaceus. Cancer Lett. 8 Jul 2007;252(1):43-54. Epub 2007 Jan 16.
- Auyeung KK, Cho CH, Ko JK. A novel anticancer effect of Astragalus saponins: Transcriptional activation of NSAID-activated gene. Int J Cancer. 1 Sep 2009;125(5):1082-1091.
- Wang JY, Ma GW, Dai SQ, et al. [Effect of cellular immune supportive treatment on immunity of esophageal carcinoma patients after modern two-field lymph node dissection] Ai Zheng. Jul 2007;26(7):778-781. Chinese.
- Gao XH, Xu XX, Pan R, Li Y, Luo YB, Xia YF, Murata K, Matsuda H, Dai Y. Saponin fraction from Astragalus membranaceus roots protects mice against polymicrobial sepsis induced by cecal ligation and puncture by inhibiting inflammation and upregulating protein C pathway. J Nat Med. Oct 2009;63(4):421-429. Epub 2009 Jun 24.
- Zhang BQ, Hu SJ, Qiu LH, et al. Effects of Astragalus membranaceus and its main components on the acute phase endothelial dysfunction induced by homocysteine. Vascul Pharmacol. Apr 2007;46(4):278-285. Epub 2006 Nov 10.
- Cho JH, Cho CK, Shin JW, Son JY, Kang W, Son CG. Myelophil, an extract mix of Astragali Radix and Salviae Radix, ameliorates chronic fatigue: a randomised, double-blind, controlled pilot study. Complement Ther Med. Jun 2009;17(3):141-146. Epub 2009 Jan 23.
- Ai P, Yong G, Dingkun G, Qiuyu Z, Kaiyuan Z, Shanyan L. Aqueous extract of Astragali Radix induces human natriuresis through enhancement of renal response to atrial natriuretic peptide. J Ethnopharmacol. 28 Mar 2008;116(3):413-421. Epub 2007 Dec 23.
- Ahmed MS, Hou SH, Battaglia MC, Picken MM, Leehey DJ. Treatment of idiopathic membranous nephropathy with the herb Astragalus membranaceus. Am J Kidney Dis. Dec 2007;50(6):1028-1032.
- Mao XQ, Yu F, Wang N, Wu Y, Zou F, Wu K, Liu M, Ouyang JP. Hypoglycemic effect of polysaccharide enriched extract of Astragalus membranaceus in diet induced insulin resistant C57BL/6J mice and its potential mechanism. Phytomedicine. May 2009;16(5):416-425. Epub 2009 Feb 6.
