Fig. 4

Expression of polarization signature molecules in periodontal tissues of mice. a Representative immunohistochemistry micrographs of periodontal tissues of maxillary second molars identifying the M1 macrophage marker iNOS. Arrows indicate areas of high expression of iNOS. R, root; AB, alveolar bone. Magnification: 200×. Scale bar, 100 μm. d The corresponding quantitative analysis of iNOS expression in periodontal tissues. b, c, e, f Real-time PCR analysis of the mRNA expression of the M1-related iNOS and TNF-α and the M2-related Arg1 and IL-10 in gingival tissues. g Correlations between bone resorption area and mRNA expression of iNOS and Arg1 and protein of iNOS (Pearson). h, i, j Expression of receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG) mRNA, and the ratio of RANKL/OPG in gingival tissues, as determined by RT-PCR. Data are presented as mean ± standard deviation. **P < 0.01 and ***P < 0.001 using one-way ANOVA with Tukey’s test