| Autor: |
Schenning, Martijn, van Tiel, Claudia M., van Manen, Daniëlle, Stam, Jord C., Gadella, Barend M., Wirtz, Karel W. A., Snoek, Gerry T. |
| Přispěvatelé: |
Amsterdam Cardiovascular Sciences, Medical Biochemistry, Other departments |
| Jazyk: |
angličtina |
| Rok vydání: |
2004 |
| Zdroj: |
Journal of lipid research, 45(8), 1555-1564. American Society for Biochemistry and Molecular Biology Inc. |
| ISSN: |
0022-2275 |
| Popis: |
Mouse fibroblast cells overexpressing phosphatidylinositol transfer protein alpha [PI-TPalpha; sense PI-TPalpha (SPIalpha) cells] show a significantly increased rate of proliferation and an extreme resistance toward ultraviolet- or tumor necrosis factor-alpha-induced apoptosis. The conditioned medium (CM) from SPIalpha cells or the neutral lipid extract from CM stimulated the proliferation of quiescent wild-type NIH3T3 cells. CM was also highly effective in increasing resistance toward induced apoptosis in both wild-type cells and the highly apoptosis-sensitive SPIbeta cells (i.e., wild-type cells overexpressing PI-TPbeta). CM from SPIalpha cells grown in the presence of NS398, a specific cyclooxygenase-2 (COX-2) inhibitor, expressed a diminished mitogenic and antiapoptotic activity. This strongly suggests that at least one of the bioactive factor(s) is an eicosanoid. In accordance, SPIalpha cells express enhanced levels of COX-1 and COX-2. The antiapoptotic activity of CM from SPIalpha cells tested on SPIbeta cells was inhibited by approximately 50% by pertussis toxin and suramin as well as by SR141716A, a specific antagonist of the cannabinoid 1 receptor. These inhibitors had virtually no effect on the COX-2-independent antiapoptotic activity of CM from SPIalpha cells. The latter results imply that PI-TPalpha mediates the production of a COX-2-dependent eicosanoid that activates a G-protein-coupled receptor, most probably a cannabinoid 1-like receptor |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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