Assuntos
Lipopolissacarídeos/toxicidade , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Vitronectina/metabolismo , Animais , Sequência de Bases , Primers do DNA , Camundongos , Camundongos Knockout , Inibidor 1 de Ativador de Plasminogênio/química , Inibidor 1 de Ativador de Plasminogênio/genéticaRESUMO
Staplabin and SMTPs, a family of triprenyl phenol metabolites of Stachybotrys microspora, enhance fibrinolysis by modulating plasminogen conformation to increase its susceptibility to activation by plasminogen activators. We found that the production of these metabolites were markedly elevated by feeding the microbial culture with an amino acid or an amino alcohol that is a partial molecular constituent of the compound. Thus, the addition of 5-aminovaleric acid, 2-aminoethanol, Ser, Phe, Leu, Trp, Orn and Lys at 100 mg/ml resulted in 7- to 45-fold increases in the production of staplabin, SMTP-1, -3, -4, -5, -6, -7 and -8, respectively. Although the feeding at day 0 to 3 of culture supported the selective production, the supplementation after 5 days had little or no effect. When non-constituent amino acids were supplemented to cultures, production of hitherto uncharacterized congeners was observed.
Assuntos
Aminoácidos/metabolismo , Amino Álcoois/metabolismo , Benzopiranos/metabolismo , Ativadores de Plasminogênio/metabolismo , Pirrolidinonas/metabolismo , Stachybotrys/metabolismo , Aminoácidos/química , Amino Álcoois/química , Cromatografia Líquida de Alta Pressão , Stachybotrys/químicaRESUMO
Rat T9 glioma cells transfected with the gene for the membrane isoform of macrophage-CSF (mM-CSF) but not for the secreted isoform of M-CSF were directly killed by bone marrow-derived macrophages. Macrophage-mediated cytolysis of the mM-CSF-transfected clone was blocked by using chemical inhibitors of phagocytosis such as iodoacetate, 2-deoxyglucose, gadolinium chloride, and cytochalasin B. In contrast, macrophage-mediated killing of mM-CSF-expressing tumor cells was augmented by the microtubule inhibitor, colchicine. Use of nitric oxide and reactive oxygen intermediate inhibitors failed to alter the macrophage-mediated killing of the mM-CSF-transfected tumor cells. Photomicroscopy, using immunohistochemical staining with the anti-Hck Ab to distinguish macrophages from tumor cells, revealed that phagocytosis began within 2 h after addition of the mM-CSF-bearing tumor cells. Photocinematography confirmed that macrophages first phagocytosized and then lysed the internalized mM-CSF transfectant cells. Using annexin V and acridine orange staining techniques, macrophages phagocytosized living mM-CSF-transfected tumor cells.