Abstract
We have examined the expression and role of autocrine fibroblast growth factors (FGFs) in human preadipocytes through their differentiation in vitro. A high-molecular weight form of FGF-2 was initially strongly expressed, but 6-9 d after induction of differentiation, its expression decreased markedly. This coincided with the first appearance of visible lipid droplets within the cells. FGF-2 (18 kDa) was not found. FGF receptor (FGFR) 1 was detected as a single band of 125 kDa that also decreased with differentiation. Its decrease preceded that of FGF-2. Despite the decrease in cell-associated FGF-2 with differentiation, secreted FGF-2 was 2.5-fold higher in the differentiated preadipocytes. To determine whether FGF-2 had an autocrine role, FGFR signaling was inhibited using recombinant adenovirus expressing dominant negative FGFR1 (RAdDN-FGFR1) and a specific inhibitor of FGFR1 signaling, PD166866. Preadipocytes transduced with RAdDN-FGFR1 expressed a truncated, 79-kDa FGFR1. Differentiation, assessed by lipid droplet formation, was completely prevented by RAdDN-FGFR1 and by PD166866. The protein content in the cell layer and glucose uptake were significantly reduced by both agents. The insulin-sensitizing drug, rosiglitazone, did not prevent the actions of RAdDN-FGFR1 or PD166866. Controlling adipose tissue growth by limiting FGF actions may provide a means to combat obesity.
| Original language | English |
|---|---|
| Pages (from-to) | 1226-1232 |
| Number of pages | 7 |
| Journal | Journal of Clinical Endocrinology and Metabolism |
| Volume | 90(2) |
| Publication status | Published - 23 Nov 2004 |
