Figure 5: DJ-1 promotes bone regeneration in a rat cranial critical-size defect model.

(a) Representative μCT images of cranial defects at 4 weeks after surgery. Cranial defect was induced and the defective site was covered with collagen membranes soaked with DJ-1 (1 μg), FGF-2 (0.1 μg) or vehicle control. The scale bar represents 2 mm. (b) Quantification of μCT images of cranial defects at 4 weeks after surgery. Total new bone formation at the defective site is expressed as a percentage of bone coverage relative to the total defective site. *P<0.05 versus the vehicle. (c) At 4 weeks after surgery, defective site sections were stained with H&E and photographed (X40, X100). The scale bar represents 500 μm. (d) Quantification of H&E stained images. Increased bone formation at the defective site in response to application of DJ-1 is shown. Bone volume in the defective site is represented as a percentage of mineralized bone tissue relative to total tissue volume. *P<0.05 and **P<0.01 versus the vehicle. (e) To detect blood vessel formation, defective site sections were immunostained with antibody against α-SMA and photographed (X100). The scale bar represents 200 μm. (f) Quantification of blood vessel in α-SMA-stained images. *P<0.05 and **P<0.01 versus the vehicle. n=8 for all groups (group 1: Vehicle, DJ-1; group 2: DJ-1, FGF-2). All data are presented as means±s.e.m.