Leukemia inhibitory factor and oncostatin M stimulate collagenase-3 expression in osteoblasts

Leukemia inhibitory factor (LIF) and oncostatin M (OSM) have multiple effects on skeletal remodeling. Although these cytokines modestly regulate collagen synthesis in osteoblasts, their effects on collagenase expression and collagen degradation are not known. We tested whether LIF and OSM regulate the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in osteoblast-enriched cells isolated from fetal rat calvariae. LIF and OSM increased collagenase-3 (MMP-13) mRNA and immunoreactive protein levels in a time- and dose-dependent manner. LIF and OSM enhanced the rate of transcription of the collagenase gene and stabilized collagenase mRNA in transcriptionally arrested cells. LIF and OSM failed to regulate the expression of gelatinase A (MMP-2) and B (MMP-9). LIF and OSM modestly stimulated the expression of TIMP-1 but did not alter the expression of TIMP-2 and -3. In conclusion, LIF and OSM stimulate collagenase-3 and TIMP-1 expression in osteoblasts, and these effects may be involved in mediating the bone remodeling actions of these cytokines.