Figure 4

Impact of long-term treatments with glucose and insulin on DPP-4 expression. Cells were treated with glucose (5 mM), insulin (0.3 nM) and glucose + insulin (5 mM and 0.3 nM) for 24 hours. (a) DPP4 gene expression in osteoblasts of controls (n = 3) and AIS patients (n = 4–6) was measured by RT-qPCR with GAPDH as endogenous control. Relative expression was analyzed with the 2^−ΔΔCT method. (b) DPP-4 protein expression in osteoblasts of controls and AIS patients (n = 3/group) was measured by Western blot with β-actin as endogenous control. *P < 0.05 and **P < 0.01 vs. untreated controls; ^##P < 0.01 and ^###P < 0.001 vs. treated controls using one-way ANOVA followed by Tukey’s post-hoc tests. Data are presented as mean ± standard deviation.