Astragalus (Astragalus membranaceus)

Traditional Indications

Astragalus is an adaptogen, antibacterial, cardiotonic, diuretic, febrifuge, hypoglycaemic, hypotensive, pectoral, tonic, uterine tonic and vasodilator. Traditional herbal medicine provides several remedies for strengthening the body's resistance to illness through effects on immune system components. (1)

Huang Qi is commonly used in Chinese herbalism. The root is a sweet tonic herb that stimulates the immune system and many organs of the body, whilst lowering blood pressure and blood sugar levels. It is particularly suited to young, physically active people, increasing stamina and endurance and improving resistance to the cold. For younger people it is superior to ginseng in this respect. Huang Qi is used especially for treatment of the kidneys and also to avoid senility. It is used in the treatment of prolapse of the uterus or anus, abscesses and chronic ulcers, chronic nephritis with oedema and proteinuria.

In TCM, astragalus is known as 黄芪 Huáng Qí and is said to be warm and sweet and to enter the Spleen and lung channels. Huáng Qí tonifies the Spleen & Lung Qi, raises Spleen & Stomach Qi and is used to treat prolapsed. Huáng Qí tonifies the Wei Qi to boost the immune system and tonifies Qi & blood due to loss of blood to treat postpartum fever. Astragalus is specific for chronic cough. (2)

Pharmacognocy

Studies in mice have shown astragalus increases the production of blood cells via increasing the hematopoietic microenvironment cell types including fibroblasts, reticular adventitial cells, and marcophages. (3)

Research has shown the root can increase the production of interferon and macrophages and help restore normal immune function in cancer patients. When combined with chemotherapy and radiotherapy Astragalus displays a potential immunomodulatory role by promoting activity of lymphocytes, natural killer cells and macrophages. (4, 5)

Results of trials show extracts of astragalus enhances Interferon- beta (IFN-beta) production and lowers inflammatory cytokine production including the cytokines IL-12, IL-6, IL-1beta and TNF-alpha due to Escherichia coli. (6) IFNs are proteins known as cytokines, molecules responsible for triggering Immune defences to help eradicate pathogens. IFN are named for their ability to "interfere" with viral replication by protecting cells from virus infections. IFNs also activate immune cells, such as natural killer cells and macrophages; they increase host defences by up-regulating antigen presentation by virtue of increasing the expression of major histocompatibility complex (MHC) antigens to help immune cells differentiate self cells from foreign invading cells. Flu like symptoms" including fever and muscle pain are caused by the production of IFNs and other cytokines. (7)

Other studies in relation to H9N2 avian influenza virus (H9N2 AIV) infection in chickens, show astragalus polysaccharide (APS) reduces H9N2 AIV replication and promotes early humoral immune responses in young chickens. The humoral immune response is mediated by antibody molecules. (8)

Huang Qi Astragalus membranaceusis part of a Chinese herbal formula called Shi Quan Da Bu Tang, traditionally used to tonify the Blood and Qi to treat anaemia, anorexia, extreme exhaustion, fatigue, kidney and spleen insufficiency and general weakness, particularly after illness and after chemotherapy. It has been found to potentiate (make it work better) chemotherapy and radiotherapy and inhibit malignant recurrences, prolong survival and prevent and ameliorate adverse toxicities in cancer treatment. (9) In Japanese herbal medicine (Kampo) the formula is known Juzen Taiho To and has been shown to increase expression of heavy metal chelating metallothioneins (MTs). (10) Shi Quan Da Bu Tang also increases transcription factor Nrf2 to support phase II detoxification thus regulate the body's detoxification and antioxidant system. (11)

1. PFAF. Astragalus 2019
2. Qi Ma. Milkvetch roots 2019
3. Liu P, Zhao H, Luo Y. Anti-Aging Implications of Astragalus Membranaceus (Huangqi): A Well-Known Chinese Tonic. Aging and disease. 2017;8(6):868-86.
4. Astragalus membranaceus. Monograph. Alternative medicine review : a journal of clinical therapeutic. 2003;8(1):72-7.
5. Ye L, Jia Y, Ji KE, Sanders AJ, Xue K, Ji J, et al. Traditional Chinese medicine in the prevention and treatment of cancer and cancer metastasis. Oncology letters. 2015;10(3):1240-50.
6. Frokiaer H, Henningsen L, Metzdorff SB, Weiss G, Roller M, Flanagan J, et al. Astragalus root and elderberry fruit extracts enhance the IFN-beta stimulatory effects of Lactobacillus acidophilus in murine-derived dendritic cells. PLoS One. 2012;7(10):e47878.
7. Various. Interferon. Wikipedia2018.
8. Kallon S, Li X, Ji J, Chen C, Xi Q, Chang S, et al. Astragalus polysaccharide enhances immunity and inhibits H9N2 avian influenza virus in vitro and in vivo. Journal of animal science and biotechnology. 2013;4(1):22-.
9. Chang I-M. Juzen-taiho-to (Shi-Quan-Da-Bu-Tang): Scientific Evaluation and Clinical Application. Evidence-based Complementary and Alternative Medicine. 2006;3(3):393-4.
10. Anjiki N, Hoshino R, Ohnishi Y, Hioki K, Irie Y, Ishige A, et al. A kampo formula Juzen-taiho-to induces expression of metallothioneins in mice. 2005;19(10):915-7.
11. Wu Q, Zhang D, Tao N, Zhu QN, Jin T, Shi JS, et al. Induction of Nrf2 and metallothionein as a common mechanism of hepatoprotective medicinal herbs. Am J Chin Med. 2014;42(1):207-21.