Fig 2: (A) (a-h) Representative vascular immunohistochemistry. OPG expression was higher in group C than in any other group. RANKL expression was higher in the other three groups, while the CP+VDN group exhibited the highest expression (black arrows indicate positive cells; scale bar, 50 µm.). (B) (a) IOD/area value of OPG was calculated with Image-Pro Plus software. (b) IOD/area value of RANKL was calculated with Image-Pro Plus software. (c) Representative RANKL/OPG value. *P<0.05, compared with groups CP and VDN; ?P>0.05, compared with group C (non-significant difference). Groups: the sham group (group C), vascular calcification group (group VDN), periodontitis group (group CP), and test group (group CP+VDN). OPG, osteoprotegerin; RANKL, receptor activator of nuclear factor-?B ligand.

Fig 3: Expression of (A) OPG, (B) RANKL and (C) the ratio of RANKL/OPG by real-time qPCR. *P<0.05, compared with groups C and CP+VDN; ?P>0.05, compared with group C (non-significant difference); ?P<0.05, compared with group CP. Groups: the sham group (group C), vascular calcification group (group VDN), periodontitis group (group CP), and test group (group CP+VDN). OPG, osteoprotegerin; RANKL, receptor activator of nuclear factor-?B ligand.

Fig 4: Expression of (A) OPG, (B) RANKL and (C) the RANKL/OPG ratio by ELISA. *P<0.05, compared with groups C and CP+VDN; ?P>0.05, compared with group C (non-significant difference); ?P<0.05, compared with group CP. Groups: the sham group (group C), vascular calcification group (group VDN), periodontitis group (group CP), and test group (group CP+VDN). OPG, osteoprotegerin; RANKL, receptor activator of nuclear factor-?B ligand.