Sclerostin And WNT-5A Gingival Protein Levels In Chronic Periodontitis And Health

Abstract

Background: Wnt signaling is fundamental to a myriad of biological processes including embryogenesis, organogenesis and tumorigenesis. It drives the expression of important genes for the proliferation, differentiation, maturation and activity of osteoblast-lineage cells. Pathways associated with Wnt signaling are regulated by their physiological antagonists such as sclerostin (SOST) as well as Wnt-5a that play important roles in the pathophysiology of several inflammatory conditions. Objectives: To compare the levels of SOST, Wnt-5a and TNF-α􀄮 between chronic periodontitis and periodontally healthy sites as well as to determine the correlation between clinical periodontal parameters and protein levels. Material and methods: In a cross-sectional assessment, 25 chronic periodontitis cases and 25 periodontally healthy controls were measured for probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), plaque index (PI) and percentage of radiographic bone loss. Gingival crevicular fluid (GCF) was collected cross sectionally from one periodontitis (deepest pocket) and one healthy (shallowest pocket) site in each case, and from one randomly selected site in each control subject. The protein levels of SOST, Wnt-5a and TNF-α􀄮 in GCF were measured by ELISA. The Shapiro-Wilk test was utilized to assess the normality of the distribution and non-parametric comparisons were performed. Results: Protein levels of SOST and Wnt-5a were similar between healthy and chronic periodontitis sites as well as the SOST levels between periodontally affected and healthy sites in the chronic periodontitis group (p > 0.05). Periodontally involved sites exhibited statistically significantly higher total Wnt-5a levels than the healthy sites in the periodontitis cases (p = 0.017). When the data were expressed as concentration, significant differences were found among the study groups (p-values range from < 0.001 to 0.003). Significant positive correlations were found between SOST and 1) full-mouth PPD (p = 0.044), CAL (p = 0.010), BOP (p = 0.035); 2) PPD of the sampled sites (p = 0.037); and 3) sites with PPD 4-6 mm (p = 0.018). A trend of a negative correlation was found between SOST and sites with a CAL 0-2 mm (p = 0.052). Among all included subjects, males showed a statistically significantly higher Wnt-5a levels than females (p = 0.031). Conclusions: Within the limitations of this cross-sectional study, sites with chronic periodontitis exhibited significantly elevated levels of Wnt-5a when compared to periodontally healthy sites in chronic periodontitis patients. No statistically significant association was found with SOST and TNF-α􀄮 levels.