IL-1 beta-induced expression of PDGF-AA isoform in rabbit articular chondrocytes is modulated by TGF-beta 1.
Interleukin 1 beta (IL-1 beta) and platelet-derived growth factor (PDGF) induced proliferation in many cell types. Both peptides are released by activated macrophages and other cells in response to injury and are thought to play a crucial role in a number of pathological processes. We found that IL-1 beta stimulates proliferation of rabbit articular chondrocytes and induces synthesis and release of PDGF into their culture medium. This effect, which is time- and dose-dependent (0.05-5 ng/ml), is restricted to PDGF-AA, one of the three PDGF isoforms; IL-1 beta effect on PDGF is inhibited by actinomycin D and alpha-amanitin, suggesting a transcriptional regulation of PDGF-A chain. IL-1 beta stimulates PDGF-AA synthesis also in the presence of indomethacin, a prostaglandin synthesis inhibitor. Transforming growth factor beta 1 (TGF-beta 1), a dimeric polypeptide which displays multiple biological activities, inhibits in a dose-dependent manner (1-10 ng/ml) PDGF-AA production induced by IL-1 beta. In a binding assay, TGF-beta 1 induces 45% decrease in specific binding sites for 125I-IL-1 beta, with no change in affinity.
Peracchia
F
F
Instituto di Richerche Farmacologische Mario Negri, Consorzio Mario Negri Sud, Santa Maria Imbarao Chieti, Italy.
Ferrari
G
G
Poggi
A
A
Rotilio
D
D
D000818:Animals; D002358:Cartilage, Articular / Q000166:cytology / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D015536:Down-Regulation; D007375:Interleukin-1 / Q000502:physiology*; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis*; D011817:Rabbits; D016212:Transforming Growth Factor beta / Q000502:physiology*
D007375:Interleukin-1; D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta