Astragalus
Astragalus tragacantha ssp. vicentinus
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Tribe:	Galegeae
Genus:	Astragalus L.
Species
See text.

Astragalus (As-trá-ga-lus) is a large genus of about 2,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere. Common names include milk-vetch (most species), locoweed (in western US, some species)^[1] and goat's-thorn (A. gummifer, A. tragacanthus). Some pale-flowered vetches are similar in appearance, but vetches are more vine-like.

[edit] Species

Astragalus glycyphyllos

Astragalus species are used as food plants by the larvae of some Lepidoptera species including the following case-bearers of the genus Coleophora: C. astragalella (feeds exclusively on A. glycyphyllos), C. cartilaginella (feeds exclusively on Astragalus), C. colutella, C. euryaula (feeds exclusively on Astragalus), C. gallipennella (feeds exclusively on A. glycyphyllos), C. hippodromica (feeds exclusively on A. gombo), C. onobrychiella (feeds exclusively on Astragalus), C. polonicella (feeds exclusively on A. arenarius) and C. vicinella.

[edit] Medicinal uses

Astragalus propinquus (also known as Astragalus membranaceus^{[clarification needed]}) has a history of use as an herbal medicine, and the biotechnology firms Geron Corporation and TA Therapeutics of Hong Kong have been working on deriving a telomerase activator from it.

In a recent news release Geron Corporation and Rita Effros from UCLA discussed the possibility of an herbal extract called TAT2 (Cycloastregenol) to be used to help combat HIV, as well as infections associated with chronic diseases or aging.^[2]

[edit] Supplement use

Despite lack of evidence and testing, extracts of Astragalus membranaceus are marketed as telomere enhancing and life prolonging extracts. However, no independent tests have confirmed that these supplements activate telomerase in humans. It has been suggested that telomerase activation might pose a theoretical increased risk of cancer because telomere shortening is a mechanism that limits cell proliferation. However, short telomeres result in chromosome instability, hence there is also a potential mechanism for telomere lengthening to protect against cancer. To date, studies of drug-induced activation of telomerase (as distinct from mutation-induced activation [1]) have shown no evidence of a cancer-promoting effect.

[edit] Ornamental use

Several species, including A. alpinus (bluish-purple flowers), A. hypoglottis (purple flowers) and A. lotoides, are grown as ornamental plants in gardens.

[edit] Toxicology

The family of Astragalus has been reviewed by Rios and Waterman, indicating that the toxicities vary from one species to another ^[3]

[edit] Selected species

This list is incomplete; you can help by expanding it.

(See external references)

[edit] Notes

[edit] External references

Wikimedia Commons has media related to: Astragalus

• Astragalus
• Large list of species
• Very large list of species (with synonyms).
• Astragalus at a Glance This fact sheet from the U.S. National Institutes of Health provides basic information about astragalus—common names, uses, potential side effects, and resources for more information.
• Astragalus alpinus This Rare Species Guide profile from the Minnesota Department of Natural Resources provides information about the basis for the species' listing, habitat, biology and life history, conservation and management, and conservation efforts.
• Chinese Milkvetch, Astragalus membranaceus, Kansas State University