Astragaloside A

Uses

Astragalosides are bioactive saponins isolated from dried roots of plants of the genus Astragalus, which is used in traditional Chinese medicine. Astragaloside A, also known as astragaloside IV, is known to have diverse protective effects for the cardiovascular, immune, digestive, and nervous systems. More specifically, it protects cardiomyocytes from apoptosis resulting from ischemia/reperfusion and inhibits inflammation signaled through TNF-α. Furthermore, astragaloside A stimulates angiogenesis, promotes the differentiation of neural stem cells, and increases neuroregeneration.

Definition

ChEBI: A pentacyclic triterpenoid that is cycloastragenol having beta-D-xylopyranosyl and beta-D-glucopyranosyl residues attached at positions O-3 and O-6 respectively. It is isolated from <ital Astragalus membranaceus var mongholicus.

benefits

Astragaloside A (Astragaloside IV) is the primary pure saponin isolated from Astragalus membranaceus, which has been widely used for the treatment of cardiovascular diseases. It is the primary pure saponin isolated from Astragalus membranaceus, which has been widely used for the treatment of cardiovascular diseases. Astragaloside IV improves post-ischemic heart function and ameliorated reperfusion arrhythmias accompanied by a significant increase in myocardial antioxidative enzyme superoxide dismutase activity in rat hearts in vitro. While, Astragaloside IV's protective effect on heart function can be partially abrogated by the nitric oxide synthase inhibitor, Nomega-nitro-L-arginine methyl ester.

Health effects

As the main active ingredient of the Chinese medicine Astragalus membranaceus, Astragaloside A has a good regulatory effect on the heart. It can protect against ischemic and hypoxic cardiomyocytes, protect the heart structure, and enhance heart function.

Pharmaceutical Applications

Astrageloside A has multiple pharmacologic effects, including anti-inflammatory, antifibrotic, antioxidative stress, anti-asthma, antidiabetes, immunoregulation, and cardioprotective effect via numerous signaling pathways. According to the existing studies and clinical practices, Astragaloside A possesses potential for broad application in many diseases.

Synthesis

Enzymatic hydrolysis of astragaloside glycosyl groups for the preparation of astragaloside methylglycosides:

a. Aspergillus niger (Aspegillusniger) in the medium containing 5% malt aqueous leachate, 1% enzyme-producing inducer - astragalus aqueous leachate, stirring and ventilated culture at a temperature of 28 ~ 30 under the condition of 50 ~ 100 hours, centrifugation and removal of bacteria to get the supernatant (containing the enzyme mixture), in the supernatant with 60 ~ 75% saturation of ammonium sulphate precipitation of the enzyme proteins, collection of protein In the supernatant, ammonium sulfate was used to precipitate the enzyme protein with 6075% saturation, and the protein was collected, which was dissolved in 1/10 volume of commonly used acetate buffer (0.02M, pH5.0), or phosphate buffer or Tris buffer, and the ammonium sulfate was removed by dialysis, and the enzyme liquid was removed by centrifugation;

b. Use 50 ml of the above enzyme solution, 3 g of astragalus saponin and 100 ml of acetate buffer (0.02 M, pH 5.0) mixed well, at a temperature of 20 ~ 55 under the condition of the reaction for 6 ~ 24 hours, and then add 1/3 volume of n-butanol to extract the saponin for three times, evaporate under reduced pressure, to get the astragalus saponin crude product. With silica gel column separation method (literature 3) to get 0.5 ~ 0.8 g of astragalus methyl glycosides, astragalus methyl glycosides conversion rate of 60 ~ 90%, compared with the original 3 grams of astragalus saponins directly extracted astragalus methyl glycosides increased by 6 times. The above enzyme solution DEAE-Cellulose ion exchange resin column method and BioRed protein preparation chromatography were used to separate and purify astragaloside methyloside enzyme protein, and the molecular weight of the enzyme was determined by SDS electrophoresis method.

Mode of action

Astragaloside IV is a well-known AM compound known for its neuroprotective effects. It acts as an antioxidant and reduces cell inflammation and oxidative stress. Astragaloside IV helps protect dopaminergic neurons and promotes neural process outgrowth, potentially therapeutic in PD. All the benefits of this compound for neurodegenerative diseases such as AD, PD, cerebral ischemia, and autoimmune encephalomyelitis. AS-IV maintains dopamine synthesis by increasing enzymes tyrosine hydroxylase (TH) and nitric oxide synthase (NOS), which are involved in neuron production pathways, neural signalling, and cell immune responses. The other mechanism of AS-IV in PD disease is the prevention of neuron pathology by a neurotoxicant called 1-methyl-4-phenylpyridium ion (MPP+) throughout the increasing cell survival, inhibiting pro-apoptosis Bax-mediated pathway and caspase protein (Caspase-3) activity which can destroy cellular structures while increasing anti-apoptosis B-cell lymphoma 2 (Bcl-2). It also protects neuron mitochondria from apoptosis and DNA damage by inducing Akt to promote binding of hexokinase-II (HK-II) and mitochondria for the protection of neural mitochondria[1].

References

[1] Veit Ny . “Potential benefits of incorporating Astragalus membranaceus into the diet of people undergoing disease treatment: An overview.” Journal of Functional Foods 77 (2021): Article 104339.