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Abstract: The effects of Dioscorea opposita (huai shan yao, HSY) on dexamethasone-induced insulin resistance were investigated in vitro and in vivo. D. opposita extract reduced significantly the blood insulin and glucose levels in dexamethasone-induced diabetic rats. In vitro, HSY significantly enhanced insulin-stimulated glucose uptake in 3T3-L1 adipocytes. Moreover, HSY increase the mRNA expression of GLUT4 glucose transporter in 3T3-L1 adipocytes. These data suggest that D. opposita has insulin sensitivity that is associated with the regulation of GLUT4 expression. [Copyright &y& Elsevier]

Abstract: Two new compounds, 28-epi-cyasterone and eriophytonoide, along with 11 known compounds, cyasterone, ajuforrestins A and B, 20-hydroxyecdysone, polypodin B, ajugalactone, 8-O-acetylharpagid, apigenin, N-[2hydroxy-(nonadecanoyl-tricosanoyl)]-4-hydroxy-trans-8-sphingenine, β-sitosterol, and daucosterol, were isolated from the aqueous ethanolic extract of the whole herb of Eriophyton wallchii Benth. The structures of 28-epi-cyasterone and eriophytonoide were elucidated as (22R,24S,25S,28S)-5β-stigmast-7-en-26-oic acid, 2β,3β,14,20,22,28-hexa hydroxy-6-oxo-γ-lactone, and 1-O-β-d-glucopyranosyl-(2S,3S,4R,8E)-2-[(2R)-2-hydroxyhexadecanoylamino]-1,3,4-octadecanetriol-8-ene, respectively, on the basis of spectral and chemical evidence. [Copyright &y& Elsevier]

Abstract: To find potent and selective inhibitors of dipeptidyl peptidase IV (DPP-IV), we synthesized a series of 2-cyanopyrrolidine derivatives with constrained imidazolidin ring and tested their activities against DPP-IV. Most of them exhibited submicromolar inhibitory activities against DPP-IV. The most potent compound among these is (S)-1-(2-(2-(3-(3,4-dimethoxyphenyl)-2-oxoimidazolidin-1-yl)ethyl-amino)acetyl)pyrrolidine-2-carbonitrile (6n), which is a 2nM DPP-IV inhibitor. [Copyright &y& Elsevier]

Abstract: A dose-dependent and significant (P<0.01) antiproliferative effect of Goldfussia psilostachys ethanolic extract was observed on K562 cells. The IC50 is ca. 0.5 μg/ml. The extract markedly increases the proportion of cell in G2/M phases and decreases the population of cells in G0/G1 phases. Moreover, the antimitotic effect is correlated with polymerization of microtubule assembly. These results indicate that G. psilostachys ethanolic extract inhibits the proliferation of K562 cells and disrupts the normal dynamic of microtubules during mitosis. [Copyright &y& Elsevier]

Three nortriterpenoids, notohamosin A (1), B (2) and C (3) with novel skeleton, and eight known compounds were isolated from the ethanol extract of the whole plants of Notochaete hamosa Benth. (Labiatae). On the basis of spectral evidence including 1D, 2D NMR, IR and MS data, their structures were elucidated. The relative configurations of compounds 1, 2 and 3 were determined according to NOESY experiments. [Copyright &y& Elsevier]