Interleukin-1 regulates FGF-2 mRNA and localization of FGF-2 protein in human osteoblasts.
Interleukin-1 (IL-1) and basic fibroblast growth factor (FGF-2) are potent stimulators of osteoclast formation. However, the role of FGF-2 in the responses to IL-1 in bone has not been reported. We examined the effect of IL-1 on FGF-2 mRNA and protein expression in human osteosarcoma MG-63 osteoblasts, normal human osteoblasts (NHOB), and osteoblasts from osteoarthritic patients (F2 and F13). IL-1 increased FGF-2 mRNA expression in osteoblasts within 1.5 to 3 h. Multiple FGF-2 protein isoforms were expressed in human osteoblasts. Twenty-four hours of treatment of MG-63 and NHOB cells with IL-1 increased the high-molecular-weight(HMW, 22/24 kDa) and low-molecular-weight (LMW, 18 kDa) FGF-2 proteins intracellularly. In contrast, IL-1 preferentially increased the LMW protein signal intracellularly as well as on the cell surface of F2 and F13 osteoblasts. We conclude that IL-1 is a major stimulator of FGF-2 expression in human osteoblasts. Furthermore, selective increases in the exportable LMW protein in osteoblasts from osteoarthritic patients may be of clinical relevance.
Sobue
T
T
Division of Endocrinology and Metabolism, Division of Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA.
Zhang
X
X
Florkiewicz
R Z
RZ
Hurley
M M
MM
D016222:Fibroblast Growth Factor 2 / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D010003:Osteoarthritis / Q000235:genetics; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics*; D014407:Tumor Cells, Cultured
D007375:Interleukin-1; D020033:Protein Isoforms; D012333:RNA, Messenger; D016222:Fibroblast Growth Factor 2