RESUMO
Dibenzocyclooctadiene lignans isolated from Schisandra chinensis showed antiproliferative effects in various human cancer cells. The methoxy groups at C-3, C-4, C-3', and C-4', the hydroxyl group at C-8', and the stereo-configuration of the biphenyl ring and the angeloyl group might have influence on these activities. Additional studies indicate that one of mechanism of action of an active compound schizantherin C in A549 human lung cancer cells was related to the inhibition of cell cycle progression in G0/G1 phase.
Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclo-Octanos/farmacologia , Lignanas/farmacologia , Schisandra/química , Linhagem Celular Tumoral , Ciclo-Octanos/isolamento & purificação , Humanos , Lignanas/isolamento & purificação , Estrutura MolecularRESUMO
The antiallergic effects of magnolol and honokiol, isolated from the bark of Magnolia obovata (family Magnoliaceae), were investigated both in vitro and in vivo. Magnolol and honokiol potently inhibited passive cutaneous anaphylaxis reactions in mice induced by IgE-antigen complex as well as compound 48/80-induced scratching behaviors. These constituents exhibited not only potent inhibitory activity on the degranulation of RBL-2H3 cells induced by IgE-antigen complex, with IC(50) values of 45 and 55 muM, respectively, but also inhibited the protein expressions of IL-4 and TNF-alpha. Based on these findings, magnolol and honokiol may improve IgE-induced allergic diseases.
Assuntos
Antialérgicos/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Prurido/tratamento farmacológico , Animais , Antialérgicos/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Imunoglobulina E/imunologia , Concentração Inibidora 50 , Lignanas/química , Masculino , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Estrutura Molecular , Prurido/induzido quimicamente , Ratos , beta-N-Acetil-Hexosaminidases/metabolismo , p-Metoxi-N-metilfenetilamina/imunologiaRESUMO
As part of an ongoing search for antioxidants from medicinal plants, 14 phenolic constitutents were isolated from the Korean endemic species Sedum takesimense Nakai. Their structures were determined as 1-(4-hydroxyphenyl)-2-(3,5-dihydroxyphenyl)-2-hydroxyethanone (5), gossypetin-8-O-beta-d-xylopyranoside (10), and 2,6-di-O-galloylarbutin (13) on the basis of spectroscopic analyses (IR, UV, 1D and 2D NMR, HR-MS) and chemical degradation, together with 11 previously known phenolics. Two of those (10 and 13) exhibited strong scavenging activities against DPPH and superoxide radicals as well as significant inhibitory effects on lipid peroxidation (IC(50) 14.0 and 10.8 microM, respectively) and LDL oxidation induced by a metal ion Cu(2+) (IC(50) 5.7 and 3.3 microM, respectively).
