Effects of Wnt3a on the CORM-3-induced osteogenic differentiation of rat BMSCs
A successful transfection with pcDNA3.1-Wnt3a or Wnt3a siRNA was confirmed by Western blotting (Fig. 5A) analysis. With overexpression of Wnt3a, the mRNA levels of Runx2 and OPN were increased by 1.34- and 1.82-fold respectively on the 3rd day (P < 0.05), and 1.40- and 1.29-fold respectively on the 7th day of osteogenic induction, compared with CORM-3 group (P < 0.05) (Fig. 5B). On the contrary, in Wnt3a-deficient cells, mRNA expressions of Runx2 and OPN were all reduced on the 3rd and the 7th day of osteogenic induction (P < 0.05) (Fig. 5C). The protein expressions of Runx2 and OPN after the osteogenic induction were similarly regulated by Wnt3a, in line with the regulation of Wnt3a on the mRNA expression (Fig. 5D-E). In Wnt3a-overexpression cells, the protein expressions of Runx2 and OPN were increased by 1.60- and 1.85-fold respectively on the 3rd day, 2.02- and 2.56-fold respectively on the 7th day of osteogenic induction, compared with CORM-3 group (P < 0.05). Moreover, mineralization in Wnt3a-overexpression cells on the 14th day of osteogenic induction was enhanced significantly, compared with CORM-3 group. The opposite effect was observed in Wnt3a-deficient cells (P < 0.05) (Fig. 5F).