Up-regulation of sFRP4 in chronic periodontitis tissues

Wnt/Fz signaling genes modulate tissue patterning and play important roles in inflammatory processes such as rheumatoid arthritis. However, the expression of these genes in periodontal disease has not been investigated. Objectives: This study aimed to compare the levels of Wnt5a, Fz5, sFRP1, sFRP4 and DKK1 mRNA in chronic periodontitis tissues to those in healthy control tissues. Methods: Gingival tissue samples were collected from 15 chronic periodontitis and 17 periodontally healthy sites. RNA was extracted from the tissue samples and subjected to RT-PCR using primers specific for Wnt5a, Fz5, sFRP1, sFRP4 and DKK1. Beta-actin was amplified as a control to ensure equal loading. The intensity of RT-PCR products was analyzed by a densitometer and normalized to the intensity of beta-actin. Differences in mRNA expression were tested using T-test or Mann-Whitney test. Results: Our results demonstrated that the mRNA expression level of sFRP4 was significantly higher in chronic periodontitis tissues compared to the healthy controls (P=0.02). In contrast, the mRNA expression levels of Wnt5a, Fz5, sFRP1 and DKK1 were not significantly different between the two groups (P=0.90, P=0.50, P=0.90 and P=0.45, respectively). Conclusion: These data suggest that sFRP4 may play an important role in the periodontal inflammatory process. (This study was supported by grants from the Graduate School and the Faculty of Dentistry, Khon Kaen University, Thailand.)