Altered gene expression in gingival tissues of the ligature-induced periodontitis rat model

Periodontitis is one of the most common bacterial and infectious diseases characterized by deepening of the periodontal pockets and loss of attachment, and tooth loss. Periodontitis is associated with high levels of various pro-inflammatory mediators, which result in extensive destruction of connective and bone tissues. The aim of this study was to investigate gene expression profiling related periodontitis in gingival tissues of the ligature induced periodontitis rat model. The periodontitis rat model was induced using ligation of the left and right maxillary second molars during 2 weeks. Micro-computed tomography (CT) was performed to identify bone loss of the teeth. To determine the gene expression profile related to periodontitis, up and down regulated gene expression was analyzed using a cDNA microarray (Affymetrix). Differentially expressed gene (DEG) analysis showed that 40 genes were expressed differentially in gingival tissues of the ligature-induced periodontitis rat model compared to those of normal rats (25 up-regulated genes and 15 down-regulated genes). The DAVID system was carried out to identify functional category and signal pathway. It was found that the regulation of these genes be associated with progress of periodontitis in gingival tissues. Microarray data may be helpful for an investigation of the mechanism in the development of periodontitis.