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ABSTRACT: Osteoporosis is a major age-related source of morbidity and mortality. Increased bone resorption mediated by osteoclasts is central to its pathogenesis. Cytokines, particularly RANKL and TNFalpha, are often increased under pathologic conditions, leading to enhanced osteoclastogenesis. Black cohosh (Actaea/Cimicifuga racemosa L), a popular herbal supplement for the treatment of menopausal symptoms, was recently shown to have the beneficial effect of preventing bone loss. Here, we demonstrate that 25-acetylcimigenol xylopyranoside (ACCX), a triterpenoid glycoside isolated from black cohosh, potently blocks in vitro osteoclastogenesis induced by either RANKL or TNFalpha. This blockage of osteoclastogenesis elicited by ACCX results from abrogation of the NF-kappaB and ERK pathways induced by either RANKL or TNFalpha, respectively. Importantly, this compound attenuates TNFalpha-induced bone loss in vivo. Therefore, ACCX represents a potential lead for the development of a new class of antiosteoporosis agents.
Chemistry & Biology 08/2007; 14(7):860-9. · 5.83 Impact Factor
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ABSTRACT: [structure: see text] An unprecedented triterpene alkaloid glycoside, designated cimicifugadine (1), with a pyridine ring incorporated to a cycloartane triterpenoid nucleus, was isolated from the roots of Cimicifuga foetida. Its structure was established on the basis of extensive spectroscopic measurements and chemical transformation with the absolute configuration at C-24 determined to be S by a modified Mosher method. It demonstrated a novel reactivity in mild acidic media whereby the cyclopropane ring is opened followed by the formation of two isomeric conjugated trienes.
Organic Letters 04/2007; 9(9):1813-6. · 5.86 Impact Factor
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ABSTRACT: Two new cycloartane-type triterpene glycosides, namely cimicifoetisides A (1) and B (2), along with seven known compounds cimigenol, 25-O-acetylcimigenol, cimigenol 3-O-beta-D-xylopyranoside, 12beta-hydroxycimigenol 3-O-beta-D-xylopyranoside, cimigenol 3-O-alpha-L-arabinopyranoside, 25-deoxyshengmanol 3-O-beta-D-xylopyranoside and cimilactone A, were isolated from the rhizomes of Cimicifuga foetida. Their structures were elucidated as cimigenol 3-O-(2'-O-acetyl)-alpha-L-arabinopyranoside (1) and 25-O-acetylcimigenol 3-O-(2'-O-acetyl)-alpha-L-arabinopyranoside (2). Both compounds 1 and 2 exhibited potent cytotoxicity against rat EAC (Ehrlich ascites carcinoma) and MDA-MB-A231 (human breast cancer) cells with IC50 values of 0.52 and 6.74 microM for 1, and 0.19 and 10.21 microM for 2, suggesting their potential for further investigation as anti-cancer agents.
Beilstein Journal of Organic Chemistry 02/2007; 3:3. · 2.52 Impact Factor
