Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.2.2.7 (heparinase)
 1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the binding of cationic liposomes, including didodecyl N-(alpha-(trimethylammonio)acetyl)-D-glutamate chloride (TMAG), to a mouse macrophage-like cell line RAW264.7 to clarify which molecules contribute to the binding of TMAG liposomes to the cell surface. Several types of TMAG liposomes encapsulating [3H]inulin, intra-aqueous markers of liposomes, were prepared and their binding characteristics were compared with those of neutral and negatively charged liposomes. The binding of TMAG liposomes to cells was superior to those of neutral and negatively charged liposomes and increased with increasing TMAG content. Scatchard plots for the binding of TMAG liposomes to the cells were approximately linear, indicating a single class of binding sites. Pretreatment of the cell surface with heparinase, heparitiase, chondroitinase ABC, or neuraminidase did not reduce the binding of TMAG liposomes. These results suggested that neuraminic acid and glycosaminoglycan on the cell surface have little contribution to TMAG liposome binding. Pretreatment of the cells with trypsin reduced the binding of TMAG liposomes in a concentration-dependent manner but did not detach the cells from the culture plates. In addition, alpha-chymotrypsin pretreatment had no effect even up to 5 micrograms/mL. Post-treatment with trypsin enhanced the release of TMAG liposomes from the cell surface in a concentration-dependent manner. These results demonstrated that TMAG liposomes bind to trypsin-sensitive proteins on the cell surface.
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PMID:Contribution of trypsin-sensitive proteins to binding of cationic liposomes to the mouse macrophage-like cell line RAW264.7. 923 17

We hypothesize that in neurodegenerative disorders such as Alzheimer's disease and human immunodeficiency virus encephalitis the neuroprotective activity of fibroblast growth factor 1 (FGF1) against several neurotoxic agents might involve regulation of glycogen synthase kinase-3beta (GSK3beta), a pathway important in determining cell fate. In primary rat neuronal and HT22 cells, FGF1 promoted a time-dependent inactivation of GSK3beta by phosphorylation at serine 9. Blocking FGF1 receptors with heparinase reduced this effect. The effects of FGF1 on GSK3beta were dependent on phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) because inhibitors of this pathway or infection with dominant negative Akt adenovirus blocked inactivation. Furthermore, treatment of neuronal cells with FGF1 resulted in ERK-independent Akt phosphorylation and beta-catenin translocation into the nucleus. On the other hand, infection with wild-type GSK3beta recombinant adenovirus-associated virus increased activity of GSK3beta and cell death, both of which were reduced by FGF1 treatment. Moreover, FGF1 protection against glutamate toxicity was dependent on GSK3beta inactivation by the PI3K-Akt but was independent of ERK. Taken together these results suggest that neuroprotective effects of FGF1 might involve inactivation of GSK3beta by a pathway involving activation of the PI3K-Akt cascades.
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PMID:Fibroblast growth factor 1 regulates signaling via the glycogen synthase kinase-3beta pathway. Implications for neuroprotection. 1209 87