Clin Res Cardiol 101, Suppl 1, April 2012

P993 - Modulation of the cell migration and the pro-angiogenic properties of murine cardiomyocytes
 
A. Eisenreich1, H.-P. Schultheiss1, U. Rauch-Kröhnert1
 
1Med. Klinik II, Klinik für Kardiologie und Pulmologie, Charité - Universitätsmedizin Berlin, Campus Benj. Franklin, Berlin;
 
Introduction: Tissue factor (TF) is the primary initiator of the blood coagulation cascade. Two TF isoforms are expressed in murine as well as human cells, soluble alternatively spliced (as)TF and “full length” (fl)TF. Recently, asTF was indicated to be involved in adhesion and angiogenesis in human endothelial cells. How asTF modulates pro-angiogenic processes is still unknown. A likely hypothesis is that asTF acts via interactions with receptors, such as integrins or PARs or other pro-angiogenic factors, such as the chemokines VEGF or FGF2. In this study, we analysed the effects of asTF in murine cardiomyocytes on cell expression and the pro-angiogenic potential as well as on the chemotaxis of monocytic cells.
Methods: Murine cardiomyocytic cell line HL-1 was either transfected with an asTF-overexpressing plasmid or an flTF-overexpressing plasmid, or treated with recombinant murine asTF or flTF, respectively. The expression asTF, flTF, FGF2 and VEGF was assed by quantitative Real-Time PCR and Western blotting. The cell proliferation, migration and endothelial tube formation was characterized via appropriate in vitro assays.
Results: Overexpression of both TF isoforms resulted in a higher proliferation rate compared to controls (flTF-overexpression: +24.5 ± 4.76% increased proliferation, asTF-overexpression: +15.0 ± 4.02% increased proliferation vs. control cells, p<0.01). Down regulation of TF by specific siRNA caused a decrease in the proliferation rate (-18.4 ± 3.24% vs. control cells, p<0.001). Treatment of cells with recombinant (r)asTF also significantly induced cell proliferation in a concentration dependent manner. In contrast to flTF-transfected HL-1 cells, asTF-overexpression in cardiomyocytes increased expression of VEGF and FGF2 compared to controls. Moreover, the supernatant of asTF-overexpressing cardiomyocytic cells induced the chemotaxis of monocytic cells and the pro-angiogenic tube formation by endothelial cells. Murine (r)asTF also induced the monocytic cell migration and endothelial tube formation, whereas, recombinant murine flTF had no influence on these processes. Finally, asTF overexpression as well as treatment of cells with (r)asTF altered cell signaling via ERL1/2 and p38 in HL-1 associated with differential modulation of the cardiomyocytic expression of VEGF and FGF2.
Conclusions: Both TF isoforms induce the cell proliferation of murine cardiomyocytes. But in contrast to flTF, asTF overexpression in cardiomyocytic cells additionally increased the pro-angiogenic properties of these cells ‑possibly- mediated by the induction of the pro-migratory and pro-angiogenic factors FGF2 and VEGF. Therefore, we conclude asTF to be a potential migration- and angiogenesis-promoting factor.
 
Clin Res Cardiol 101, Suppl 1, April 2012
Zitierung mit Vortrags- oder Posternummer s.o.
DOI 10.1007/s00392-012-1100-6

http://www.abstractserver.de/dgk2012/ft/abstracts/P993.htm