Effects of triterpene saponins from Astragalus species on in vitro cytokine release

• Published in: Journal of ethnopharmacology 2005-01, Vol.96 (1), p.71-77
• Main Authors: Yesilada, Erdem, Bedir, Erdal, Çalış, İhsan, Takaishi, Yoshihisa, Ohmoto, Yasukazu
• Format: Article
• Language: English
• Subjects: Adjuvants, Immunologic - chemistry; Adjuvants, Immunologic - isolation & purification; Adjuvants, Immunologic - pharmacology; anticarcinogenic activity; Antineoplastic Agents - chemistry; Antineoplastic Agents - isolation & purification; Antineoplastic Agents - pharmacology; Astragalus; Astragalus Plant; Astragalus spp; Biological and medical sciences; Cycloartane triterpene glycosides; cytokines; Cytokines - blood; Enzyme-Linked Immunosorbent Assay; Fabaceae; General pharmacology; Humans; immunostimulants; In Vitro Techniques; Interferon-gamma - blood; Interferone-γ; Interleukin-1 - blood; Interleukin-1β; Interleukin-2; Interleukin-2 - blood; Interleukin-4; Interleukin-4 - blood; Interleukin-8; Interleukin-8 - blood; Lipopolysaccharides - pharmacology; Medical sciences; medicinal plants; Oleanan triterpene glycosides; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; plant extracts; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plant Roots - chemistry; roots; Saponins - chemistry; Saponins - isolation & purification; Saponins - pharmacology; traditional medicine; Triterpene saponins; Triterpenes - chemistry; Triterpenes - isolation & purification; Triterpenes - pharmacology; triterpenoid saponins; Tumor Necrosis Factor-alpha - biosynthesis; Tumor necrosis factor-α
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2004.08.036

Roots of Astragalus species are used to treat leukemia and for wound healing in Turkish folk medicine. In order to evaluate this information, the effect of 13 cycloartane- and 1 oleanan-type triterpene saponins isolated from Turkish species ( Astragalus brachypterus, Astragalus cephalotes, Astragalus microcephalus, and Astragalus trojanus), as well as methanol extracts from the roots of three Astragalus species ( Astragalus cephalotes, Astragalus oleifolius and Astragalus trojanus) were studied. Cytokine concentrations of interleukins IL-1β, IL-8 and TNF-α after bacterial lipopolysaccharide (LPS) and IL-2, IL-4 and INF-γ after phorbolacetate (PHA) stimulation were determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. All triterpene saponins tested in the present study showed a prominent IL-2 inducing activity between 35.9% and 139.6%. Among the extracts the highest score was obtained for Astragalus oleifolius (141.2%). Glycosides of 20,24-epoxy and 20,25-epoxy cycloartanes showed higher IL-2 inducing activity than those of acyclic-cycloartane derivatives as well as aglycone of 20,24-epoxy cycloartanes, cycloastrogenol. Especially the activity of Astragaloside VII, a tridesmosidic glycoside of cycloastrogenol, was the most remarkable. The oleanan-type triterpene saponin also showed a prominent IL-2 inducing activity. IL-2 is a cytokine produced by activated T cells, which has shown powerful immunostimulatory and antineoplastic properties. Accordingly, the IL-2 inducing activity of the triterpene saponins might be the mechanism involved in order to explain the immunomodulatory and anticancer effects of Astragalus species.