scholarly journals Changes in fibroblast growth factor 2 and its receptors in bovine follicles before and after GnRH application and after ovulation

Reproduction ◽  
2006 ◽  
Vol 131 (2) ◽  
pp. 319-329 ◽  
Author(s):  
Bajram Berisha ◽  
Martin Steffl ◽  
Werner Amselgruber ◽  
Dieter Schams
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Fibroblast Growth Factor 2 ◽  
Corpora Lutea ◽  
Fibroblast Growth ◽  
Lh Surge ◽  
Short Period ◽  
Before And After ◽  
Capillary Endothelial Cells

The aim of this study was to evaluate the expression pattern of fibroblast growth factor 2 (FGF2), its receptor variants (FGFR1IIIc, FGFR2IIIc) and nucleolin in time-defined follicle classes before and after GnRH application and after ovulation in the cow. Ovaries containing preovulatory follicles or new corpora lutea (CL) were collected at approximately 0, 4, 10, 20 and 25 h (follicles) and 60 h (new CL) relative to injection of GnRH to induce an LH surge (n= 5 animals per group). The expressions of FGF2 and FGFR1IIIc mRNA were significantly up-regulated only in the follicle group 4 h after GnRH (during the LH surge) with a significant down-regulation immediately afterwards. Western blot analyses showed two protein bands with at 22 and 18 kDa with apparent up-regulation beginning with the LH surge (4 h) and maximum levels 20 h after GnRH. FGF2 protein in follicles collected at 0 h (before LH surge) was localised in theca tissue (endothelial and pericytes of blood vessels) but not in granulosa cells (GCs). The FGF2 staining (by immunohistochemistry) pattern changed dramatically after the LH surge for a short period (about 2 days) and FGF2 protein was localised dominantly in the nucleus of many GCs, while most capillary endothelial cells were FGF2 immunonegative. In conclusion, the novel observation of FGF2 up-regulation and the distinct change in FGF2 localisation from theca (cytoplasm of endothelial cells) to the nucleus of GCs after the LH surge may be important for survival of GCs or for the transition of the GCs to luteal cells.

scholarly journals The opposing effects of basic fibroblast growth factor and transforming growth factor beta on the regulation of plasminogen activator activity in capillary endothelial cells.

1987 ◽  
Vol 105 (2) ◽  
pp. 957-963 ◽  
Author(s):  
O Saksela ◽  
D Moscatelli ◽  
D B Rifkin
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Plasminogen Activator ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Fibroblast Growth ◽  
Tgf Beta ◽  
Capillary Endothelial Cells ◽  
Growth Factor Beta

Basic fibroblast growth factor (bFGF), a potent inducer of angiogenesis in vivo, stimulates the production of both urokinase- and tissue-type plasminogen activators (PAs) in cultured bovine capillary endothelial cells. The observed increase in proteolytic activity induced by bFGF was effectively diminished by picogram amounts of transforming growth factor beta (TGF beta), but could not be abolished by increasing the amount of TGF beta. However, the inhibition by TGF beta was greatly enhanced if the cells were pretreated with TGF beta before addition of bFGF. After prolonged incubation of cultures treated simultaneously with bFGF and TGF beta, the inhibitory effect of TGF beta diminished and the stimulatory effect of the added bFGF dominated as assayed by PA levels. TGF beta did not alter the receptor binding of labeled bFGF, nor did a 6-h pretreatment with TGF beta reduce the amount of bFGF bound. The major difference between the effects of bFGF and TGF beta was that while bFGF effectively enhanced PA activity expressed by the cells, TGF beta decreased the amounts of both cell-associated and secreted PA activity by decreasing enzyme production. Both bFGF and TGF beta increased the secretion of the endothelial-type plasminogen activator inhibitor.

THE OPPOSING OF BASIC FIBROBLAST GROWTH FACTOR AND TRANSFORMING GROWTH FACTOR BETA ON THE REGULATION OF PLASMINOGEN ACTIVATOR ACTIVITY IN CAPILLARY ENDOTHELIAL CELLS

1987 ◽  
Author(s):  
O Saksela ◽  
D Moscatelli ◽  
D B Rifkin
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Basic Fibroblast Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Fibroblast Growth ◽  
Capillary Endothelial Cells ◽  
Growth Factor Beta ◽  
Pai 1

Basic fibroblast growth factor (bFGF), a potent inducer of angio-genesis in vivo, stimulates the production of both the cell-associated and the secreted forms of urokinase-and tissue-type plasminogen activators (PA) in cultured bovine capillary endothelial cells. This stimulation was counteracted by picogram amounts of transforming growth factor beta The stimulatory effect of bFGF was not completely abolished by increasing the amount of TGFb However, the inhibition by TGFb was greatly enhanced if the cells were pretreated for 1-3 hours with TGFb before addition of bFGF, and the inhibition was almost total, if the' preincubationtime with TGFb was 6 hours.Sequential chanqes of serum-containing medium prior to addition ofbFGF also blocked the PA stimulatory effect of bFGF. This inhibitory activity of serum was reduced by incubation of the serum with anti-TGFb-IgG. After pro-longed incubation of cultures treated simultaneously with bFGF' and TGFb, the inhibitory effect of the added bFGF dominated as assayed by PAlevels. TGFbdid not alter the receptor binding of labeled bFGF, nor did a 6 hour pretreatment with TGFb reducethe amount of bound bFGF. The major difference between effects by bFGF and TGFb was thatwhile bFGF effectively enhanced PA-activi-ty expressed by the cells, TGF decreased the amounts of both cell-associated and secreted PA activity by decreasing enzyme production and proenzyme activation. Both bFGF and TGFb increased the secretion of the endothelial type 1 plasminogen activatorinhibitor (PAI 1). The highest concentration of TGFb is found in platelets, and it is known to be released during clot formation. The suppression of PA production by theendothelium by the release of TGFb shouldresult in a decrease in the fibrinolytic activity and promote clot maintenance. In addition, the rapid stimulation of high levels of PAI 1 secretion from the surrounding capillarycells by platelet released TGFb may further suppress fibrinolysis'. The reversabil it.y of theTGFb effect and domination of bFGF stimulation may be important in relation to the subsequentonset of clot lysis or angiogenesis leadino to thrombus reorganization and wound healing.

scholarly journals Cell Density-Dependent Fibroblast Growth Factor-2 Signaling Regulates Syndecan-4 Expression in Cultured Vascular Endothelial Cells

2020 ◽  
Vol 21 (10) ◽  
pp. 3698 ◽  
Author(s):  
Takato Hara ◽  
Shiori Yabushita ◽  
Chika Yamamoto ◽  
Toshiyuki Kaji
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Heparan Sulfate ◽  
Fibroblast Growth Factor ◽  
Cell Density ◽  
Vascular Endothelial Cells ◽  
Fibroblast Growth Factor 2 ◽  
Vascular Endothelial ◽  
Fibroblast Growth ◽  
Density Dependent

Syndecan-4 is a member of the syndecan family of transmembrane heparan sulfate proteoglycans, and is involved in cell protection, proliferation, and the blood coagulation-fibrinolytic system in vascular endothelial cells. Heparan sulfate chains enable fibroblast growth factor-2 (FGF-2) to form a complex with its receptor and to transduce the cell growth signal. In the present study, bovine aortic endothelial cells were cultured, and the intracellular signal pathways that mediate the regulation of syndecan-4 expression in dense and sparse cultures by FGF-2 were analyzed. We demonstrated the cell density-dependent differential regulation of syndecan-4 expression. Specifically, we found that FGF-2 upregulated the synthesis of syndecan-4 in vascular endothelial cells via the MEK1/2-ERK1/2 pathway in dense cell cultures, with only a transcriptional induction of syndecan-4 at a low cell density via the Akt pathway. This study highlights a critical mechanism underlying the regulation of endothelial cell functions by proteoglycans.

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