scholarly journals Effect of transforming growth factor-β1 and basic fibroblast growth factor on the expression of cell surface proteoglycans in human lung fibroblasts. Enhanced glycanation and fibronectin-binding of CD44 proteoglycan, and down-regulation of glypican

1995 ◽  
Vol 310 (1) ◽  
pp. 73-81 ◽  
Author(s):  
M Romarís ◽  
A Bassols ◽  
G David

We have tested the effects of transforming growth factor-beta 1 (TGF-beta 1), basic fibroblast growth factor (bFGF) and TGF-beta 1 + bFGF on the expression of the cell surface proteoglycans (CD44, syndecans and glypican) in cultures of human lung fibroblasts (HLF). Cell surface proteoglycan expression was monitored by quantitative immunoprecipitation from metabolically labelled cells. Western and Northern blotting and evaluation of the glycanation of the proteoglycans. Stimulation of the cells with TGF-beta 1 increased the length of the chondroitin sulphate (CS) chains on CD44 (approximately 1.6-fold). bFGF, administered solely, also increased the length of the CS chains on CD44 (approximately 1.4-fold), whereas the combination of TGF-beta 1 + bFGF nearly doubled both the length and the number of the CS chains on CD44. None of these treatments lead to changes in CD44 message or core-protein expression. This enhanced glycanation of CD44 after the TGF-beta 1, bFGF and combined treatments correlated with a 2-fold increase in the affinity of the proteoglycan for fibronectin but had no influence on the binding to type I collagen. TGF-beta 1, alone or in combination with bFGF, also stimulated the CS content of syndecan-1, but none of the other syndecans was significantly affected by any of the factors or combinations tested. The expression of glypican however was significantly decreased (nearly halved) by the combination of TGF-beta 1 + bFGF, less so by TGF-beta 1 and not at all by bFGF. This decrease occurred both at the level of the message and of the core protein. These data demonstrate specific and differential effects of TGF-beta 1 and bFGF on the structure, expression and interactions of the cell surface proteoglycans of HLF.

1999 ◽  
Vol 20 (5) ◽  
pp. 1020-1027 ◽  
Author(s):  
Carina Becerril ◽  
Annie Pardo ◽  
Martha Montaño ◽  
Carlos Ramos ◽  
Remedios Ramı́rez ◽  
...  

1995 ◽  
Vol 311 (2) ◽  
pp. 393-399 ◽  
Author(s):  
E Berrou ◽  
R Quarck ◽  
M Fontenay-Roupie ◽  
S Lévy-Toledano ◽  
G Tobelem ◽  
...  

Basic fibroblast growth factor (bFGF) was internalized by smooth muscle cells (SMC) from pig aorta. Correlation between heparin inhibition of binding and late internalization (8 h) implicated low-affinity sites in bFGF internalization. Transforming growth factor-beta 1 (TGF-beta 1) induced a 38% increase in bFGF internalized between 4 and 8 h. While bFGF and/or TGF-beta 1 enhanced cell-surface proteoglycan synthesis, 35S-labelled proteoglycans of the extracellular matrix (ECM) were not affected. This might be explained by the different turnover rates displayed by the two populations of proteoglycans. Although bFGF and/or TGF-beta 1 induced a similar stimulation in cell-surface chondroitin sulphate/dermatan sulphate and heparan sulphate (HS) proteoglycan synthesis, only the turnover of HS proteoglycans was increased. Twice as much HS proteoglycan was internalized in the presence of TGF-beta 1 or bFGF. Furthermore, TGF-beta 1 induced a 43 +/- 12% increase in HS proteoglycan internalized in the presence of bFGF with a parallel 38% increase in bFGF internalization. Overall, the results indicated that bFGF bound to two HS proteoglycan populations. bFGF storage (70% of bFGF bound to SMC) was not affected by TGF-beta 1 under our conditions and involved ECM proteoglycans characterized by a low turnover. bFGF internalization up-regulated by TGF-beta 1 involved cell-surface HS proteoglycan characterized by a high turnover.


1987 ◽  
Vol 105 (2) ◽  
pp. 957-963 ◽  
Author(s):  
O Saksela ◽  
D Moscatelli ◽  
D B Rifkin

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.


Cytokine ◽  
2003 ◽  
Vol 24 (1-2) ◽  
pp. 25-35 ◽  
Author(s):  
Eleni Papakonstantinou ◽  
Alexios J Aletras ◽  
Michael Roth ◽  
Michael Tamm ◽  
George Karakiulakis

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