GPR1, chemerin, and AR expression in osteogenic differentiated bMSCs isolated from WT mice. (A) Alizarin Red S staining of ECM of bMSCs, photomicrographs (×4). (B) Quantification of ECM mineralisation by measuring Alizarin Red S extracted in 10% CPC solution. Statistical significance was assessed by the two-tailed Student t test; ***p < 0.001 versus control in each day; N = 3. (C) RT-qPCR analysis of mRNA levels for GPR1, chemerin and AR during WT MSC osteogenesis. All values are expressed relative to the mRNA levels measured on Day 0 and represent the mean ± standard error of the mean. Statistical significance was assessed by one-way ANOVA followed by Bonferroni; *p < 0.05 versus Day 0, N = 3. ANOVA = analysis of variance; AR = androgen receptor; bMSCs = bone marrow-derived mesenchymal stem cells; ECM = extracellular matrix; GPR1 = G protein-coupled receptor 1; RT-qPCR = real-time quantitative polymerase chain reaction; WT = wild type.