title: Down-regulation of c-jun N-terminal kinase-activator protein-1 signaling pathway by Ginkgo biloba extract in human peripheral blood T cells.
abstract: The activation of T lymphocytes contributes to inflammatory process of cardiovascular and cerebrovascular diseases. We investigated the effects of the extract of Ginkgo biloba (EGb), an ancient plant preserving antioxidant property, on phorbol 12-myristate 13-acetate+ionomycin or anti-CD3+anti-CD28 monoclonal antibodies-activated T cells. Human peripheral blood T cells were negatively selected from whole blood. Cytokines were measured by ELISA, cell surface markers by flow cytometry and the activities of transcription factors and kinases were determined by electrophoresis mobility shift assays, kinase assays and transfection assays. We showed that EGb inhibited several cytokines, including tumor necrosis factor-alpha, interleukin (IL)-2, IL-4 and interferon-gamma production from activated T cells. Electrophoresis mobility shift assay analysis indicated that EGb down-regulated activator protein-1 (AP-1) but not nuclear factor kappa B DNA-binding activity. In addition, EGb inhibited c-jun N-terminal kinase but not extracellular signal regulated protein kinase activity. The inhibitory specificity on AP-1 by EGb was also demonstrated in transfection assays. The inhibition of AP-1 signaling pathway in T cells by EGb provides a support for its efficacy in cardiovascular and cerebrovascular diseases and raises a therapeutic potential for this drug in activated T cell-mediated pathologies.
authors.affiliation: Graduate Institute of Medical Science, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Shu-Meng
authors.initials: SM
authors.lastname: Cheng
authors.forename: Shih-Ping
authors.initials: SP
authors.lastname: Yang
authors.forename: Ling-Jun
authors.initials: LJ
authors.lastname: Ho
authors.forename: Tien-Ping
authors.initials: TP
authors.lastname: Tsao
authors.forename: Ting-Yi
authors.initials: TY
authors.lastname: Juan
authors.forename: Deh-Ming
authors.initials: DM
authors.lastname: Chang
authors.forename: Sun-Yran
authors.initials: SY
authors.lastname: Chang
authors.forename: Jenn-Haung
authors.initials: JH
authors.lastname: Lai
mesh_terms: D016207:Cytokines / Q000096:biosynthesis; D004247:DNA / Q000378:metabolism; D015536:Down-Regulation; D020441:Ginkgo biloba; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D016328:NF-kappa B / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000502:physiology*
chemical_list: D016207:Cytokines; D016328:NF-kappa B; D010936:Plant Extracts; D018808:Transcription Factor AP-1; D004247:DNA; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases