Essential roles of oncostatin M receptor β signaling in renal crystal formation in mice

Oncostatin M (OSM), a member of the IL-6 family of cytokines, has important roles in renal diseases. The relationship between OSM and kidney stone disease, however, remains unclear. To investigate the roles of OSM in the development of kidney stone disease, we generated a mouse model of renal crystal formation using OSM receptor β (OSMRβ)-deficient mice (OSMRβ−/− mice). There were fewer renal crystal deposits in OSMRβ−/− mice than in wild-type (WT) mice. Crystal-binding molecules (osteopontin, annexin A1, and annexin A2), inflammatory cytokines (TNF-α and IL-1β), and fibrosis markers (TGF-β, collagen 1a2, and α-smooth muscle actin) were also decreased in the kidneys of OSMRβ−/− mice compared with those in WT mice. Immunofluorescence staining showed that OSMRβ was expressed in renal tubular epithelial cells (RTECs) and renal fibroblasts in the model of renal crystal formation. In the cultured RTECs and renal fibroblasts, OSM directly induced the expression of crystal-binding molecules and fibrosis markers. Expressions of inflammatory cytokines were increased by stimulation with OSM in cultured renal fibroblasts. OSM may promote the formation of renal crystal deposits by directly acting on RTECs and renal fibroblasts to produce crystal-binding molecules and inflammatory cytokines.