Astragalus

Synonym(s): Astragalus membranaceus, Astragalus propinquus, Mongolian milkvetch, Astragalus root extract, tragacanth

Nutrient group: plant extracts & active ingredients

Sources and physiological effects

Dietary sources
Astragalus membranaceus is a subspecies of the plant genus Astragalus and originally thrives in northern areas of China and Mongolia, which is why it is also called Astragalus mongholicus. It is one of the most important plants in traditional Chinese medicine (TCM). Among the valuable ingredients of the root are complex polysaccharides, isoflavonoids and triterpene saponins such as astragalosides. In China the root is also used for soups and teas.
Physiological effects
Immune system	Influence on the regulation of monocyte proliferation Activation of B cells and macrophages Increase in cytokine production

Detailed information

Astragalus membranaceus – an immunostimulator of traditional Chinese medicine

Astragalus membranaceus is one of the most important medicinal herbs in Traditional Chinese Medicine (TCM). Recent findings suggest that the Far Eastern papilionaceous plant not only contributes to our general well-being, but also supports our immune system in several ways (1). Specific polysaccharide fractions, which can activate both macrophages and B cells, seem to be responsible for the proven immunostimulatory effects (2). In 2013, a team of researchers discovered that astragaloside II, an important active ingredient of the Astragalus membranaceus, can increase the activity of an enzyme called CD45 phosphatase, thereby activating certain white blood cells that serve as immune defence (Th-1 cell activation) (3). Our immune system is also supported by other mechanisms, including the inhibition of certain inflammatory substances (cytokines) and the regulation of the balance between effector cells and regulatory T cells. Astragalus extract also regulates the proliferation of monocytes, improves the effect of T lymphocytes on tumor cells by specifically promoting phagocytosis activity and increases cytokine production (TNF-alpha and IL-6) (4). In addition to the positive effects on the immune system, Astragalus membranaceus also seems to be suitable for adjuvant use in chemotherapy. As an adjuvant it increases the effectiveness of chemotherapy and may reduce toxic side effects (5).

Indications

Effect	Indication	Dosage
Physiological effects at a low intake	Preventive at times of increased infection risk	100 – 200 mg/d
	Complementary therapy for weakened immune defense	400 – 500 mg/d
	Complementary therapy for tumor therapy	400 – 500 mg/d

Administration

General mode of administration
When	Astragalus extract should be taken between meals.
Side effects
No side effects are known to date.
Contraindications
No contraindications are known to date.

Interactions

Drug interactions
None	No relevant interactions are known to date.
Nutrient interactions
None	No relevant interactions are known to date.

References

1) Qi, Y. et al. 2017. Anti-Inflammatory and Immunostimulatory Activities of Astragalosides. Am J Chin Med. 45(6):1157–67.
2) Shao, B. M. et al. 2004. A study on the immune receptors for polysaccharides from the roots of Astragalus membranaceus, a Chinese medicinal herb. Biochemical and Biophysical Research Communications 320, Nr. 4: 1103–1111. doi:10.1016/j.bbrc.2004.06.065.
3) Wan, C. P. et al. 2013. Astragaloside II triggers T cell activation through regulation of CD45 protein tyrosine phosphatase activity. Acta Pharmacol Sin. 34(4):522–30.
4) Wang, R. T. et al. 2002. Extracorporeal experimental study on immuno-modulatory activity of Astragalus membranaceus extract. Zhongguo Zhong Xi Yi Jie He Za Zhi. 22(6):453-6.
5) Mcculloch, M. 2006. Astragalus-Based Chinese Herbs and Platinum-Based Chemotherapy for Advanced Non-Small-Cell Lung Cancer: Meta-Analysis of Randomized Trials. Journal of Clinical Oncology 24, Nr. 3: 419–430. doi:10.1200/jco.2005.03.6392.

References Interactions
Stargrove, M. B. et al. Herb, Nutrient and Drug Interactions: Clinical Implications and Therapeutic Strategies, 1. Auflage. St. Louis, Missouri: Elsevier Health Sciences, 2008.
Gröber, U. Mikronährstoffe: Metabolic Tuning – Prävention – Therapie, 3. Auflage. Stuttgart: WVG Wissenschaftliche Verlagsgesellschaft Stuttgart, 2011.
Gröber, U. Arzneimittel und Mikronährstoffe: Medikationsorientierte Supplementierung, 3. aktualisierte und erweiterte Auflage. Stuttgart: WVG Wissenschaftliche Verlagsgesellschaft Stuttgart, 2014.