Gender Differences in Apoptosis Biomarkers Within Normal and Diseased Gingiva

Objectives: Previous studies report that males have a greater incidence of periodontal disease than females. Thus, we compared biomarkers of gingival apoptosis from normal sites and sites of clinical attachment loss (CAL), which might indicate a possible cause for this gender disparancy. Methods: This study was approved by the IRB of the University of Mississippi Medical Center. The 76 gingival samples were obtained from Hispanic subjects (43 females, 33 males). Gingivae were obtained prior to the extraction of the adjacent teeth. They were grouped based on CAL: 0-2 (“normal-slight”, NS), 3-4 (“moderate”, M), and >5 mm (“severe”, Sev). Tissues were solubilized in PBS containing a protease inhibitor and total protein concentrations were assessed using a bicinchoinic acid assay. Survivin (SV), FAS, p38, ERK, TRAIL, and IL-2 were assessed by ELISA and data recorded as pg or ng/mg protein. These data were compared by factorial ANOVA and post-hoc Tukey tests. p<0.05 was used to reject the null hypothesis. Results: At Sev sites,FAS, p38, ERK, TRAIL, and IL-2 were significantly greater in females than males (p<0.05). At M sites, p38, TRAIL and IL-2 concentrations were significantly greater in females, than in males. At NS sites, concentrations of all of the biomarkers in both genders were significantly lower than at SEV and M sites. Concentrations of SV, p38 and TRAIL were significantly greater in females than males; concentrations of FAS and ERK were significantly greater in males than in females. Conclusions: Our data report gender-based differences in the gingival apoptotic environment at both NS and diseased sites, with males having higher concentrations of apoptotic biomarkers at severely diseased sites. Thus males may have a greater incidence of periodontal disease due to reduced tissue apoptosis, indicating a reduced response to a chronic bacterial challenge.