RESUMO
Phytochemical investigation of the roots and stems of Illigera luzonensis afforded two new aporphine alkaloids (1) and (2), one new bisdehydroaporphine alkaloid (3), and one new benzenoid (4), along with 28 known structures. The structures of new compounds were elucidated by spectral and MS analysis. Among the isolated compounds, (1) and (4-13) were subjected into the examination for their inhibitory effects on the aggregation of washed rabbit platelets.
Assuntos
Hernandiaceae/química , Extratos Vegetais/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Aporfinas/química , Hernandiaceae/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , CoelhosRESUMO
Fruiting bodies of Taiwanofungus camphoratus have been widely used as an antidote for food poisoning and considered to be a precious folk medicine for anti-inflammation and hepatoprotection. Zhankuic acid A (ZAA) is its major pharmacologically active compound. Janus kinase 2 (JAK2), whose activation is involved in cytokine signaling, plays critical roles in the development and biology of the hematopoietic system. JAK2 has been implicated as a therapeutic target in inflammatory diseases. The HotLig modeling approach was used to generate the binding model for ZAA with JAK2, showing that ZAA could bind to the ATP-binding pocket of JAK2 exclusively via the H-bond. The interaction between ZAA and JAK2 was verified by antibody competition assay. Binding of ZAA to JAK2 reduced antibody recognition of native JAK2. The expressions of phosphorylated JAK2 and STATs were analyzed by immuno-blotting. ZAA reduced the phosphorylation and downstream signaling of JAK2, and inhibited the interferon (IFN)-γ/signal transducer and activator of transcription (STAT) 1/interferon regulatory factor (IRF)-1 pathway. The protective effect of ZAA on liver injury was evaluated in mice by Con-A-induced acute hepatitis. Pre-treatment with ZAA also significantly ameliorated acute liver injury in mice. Therefore, ZAA can inhibit JAK2 phosphorylation and protect against liver injury during acute hepatitis in mice. In this study, we present data that ZAA exerts anti-inflammatory effects through the JAK2 signaling pathway. As such, ZAA may be a potential therapeutic agent for the treatment of inflammatory diseases.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Concanavalina A/toxicidade , Ergosterol/análogos & derivados , Janus Quinase 2/antagonistas & inibidores , Mitógenos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ergosterol/química , Ergosterol/farmacologia , Ergosterol/uso terapêutico , Expressão Gênica , Humanos , Janus Quinase 2/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Estrutura Molecular , Baço/citologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/fisiologiaRESUMO
Phytochemical investigation of the heartwood of Michelia compressa afforded forty-four compounds, which were identified by comparison of experimental and literature analytical and spectroscopic data. Some compounds were evaluated for their anti-inflammatory and anticancer bioactivities. The result showed that soemerine (1) and cyathisterol (2) exhibited significant nitric oxide (NO) inhibition, with IC50 values of 8.5±0.3 and 9.6±0.5 µg/mL, respectively. In addition, liriodenine (3) and oliveroline (4) exhibited cytotoxicity to human nasopharyngeal carcinoma (NPC-TW01), non-small cell lung carcinoma (NCI-H226), T cell leukemia (Jurkat), renal carcinoma (A498), lung carcinoma (A549) and fibrosarcoma (HT1080) cell lines with IC50 values in the range of 15.7-3.68 µM.
Assuntos
Anti-Inflamatórios/química , Antineoplásicos/química , Aporfinas/química , Magnoliaceae/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Aporfinas/isolamento & purificação , Aporfinas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células Jurkat , Magnoliaceae/metabolismo , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
TLR4, a membrane receptor that functions in complex with its accessory protein myeloid differentiation factor-2 (MD-2), is a therapeutic target for bacterial infections. Taiwanofungus camphoratus is highly valued as a medicinal mushroom for cancer, hypertension, and inflammation in traditional medicine. Zhankuic acid A (ZAA) is the major pharmacologically active compound of T. camphoratus. The mechanism of action of T. camphoratus or ZAA has not been fully elucidated. We analyzed the structure of human TLR4/MD-2 complex with ZAA by X-score and HotLig modeling approaches. Two Abs against MD-2 were used to verify the MD-2/ZAA interaction. The inflammation and survival of the mice pretreated with ZAA and injected with LPS were monitored. The modeling structure shows that ZAA binds the MD-2 hydrophobic pocket exclusively via specific molecular recognition; the contact interface is dominated by hydrophobic interactions. Binding of ZAA to MD-2 reduced Ab recognition to native MD-2, similar to the effect of LPS binding. Furthermore, ZAA significantly ameliorated LPS-induced endotoxemia and Salmonella-induced diarrhea in mice. Our results suggest that ZAA, which can compete with LPS for binding to MD-2 as a TLR4/MD-2 antagonist, may be a potential therapeutic agent for gram-negative bacterial infections.