Fig. 3

a Serum P1NP (ng/ml) determined by ELISA. b, c Gene expression (AU) of Alp and Bglap, determined by RT qPCR in tibia homogenates, in WT and TNF-tg animals receiving either vehicle or corticosterone (100 μg/mL) in drinking water over 3 weeks. d Representative image of primary human pre-osteoblasts and mature nodule forming osteoblasts in vitro stained with alizarin red. e Pro-collagen 1 α1 formation determined by ELISA and f quantification of gene expression (arbitrary units) of Bglap, determined by RT qPCR in primary cultures of mature osteoblasts treated with either vehicle, TNFα (10 ng/ml), corticosterone (1 μmol/l) or a combination of TNF and corticosterone for 48 h. g Serum CTX-1 (ng/ml) determined by ELISA in WT and TNF-tg animals receiving either vehicle or corticosterone. h TRAP +ve cells per well and i % calcified matrix resorption in primary human osteoclasts cultures treated with either vehicle, TNFα (10 ng/ml), corticosterone (1 μmol/l) or a combination of TNFα and corticosterone over differentiation from mononuclear cells. Values are expressed as mean ± standard error of six animals or primary cultures derived from six separate individuals. Statistical significance was determined using either two-way or one-way ANOVA with Tukey post hoc analysis. *P < 0.05, **P < 0.005, ***P < 0.001