Effect of diacerein in the treatment of induced periodontal disease in rat molars

• Grant number: 18/11757-9
• Support type: Scholarships in Brazil - Master
• Effective date (Start): October 01, 2018
• Effective date (End): March 31, 2020
• Field of knowledge: Health Sciences - Dentistry
• Cooperation agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Paulo Sergio Cerri
• Grantee: Renata Cristina Lima Silva
• Home Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Periodontal disease (PD), triggered by subgingival bacterial accumulation, leads to degradation of soft and mineralized tissues of the periodontium. The immunoinflammatory response promotes recruitment of specific mediator-releasing cells, among these mediators interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-±) and matrix metalloproteinases (MMPs) have a participation in the PD. Therefore, modulating the immunoinflammatory response may be a complementary approach in the treatment of PD. There is evidence that diacerein, an anti-IL-1 medication, reduces the production of MMPs and TNF-alfa. Thus, it is likely that diacerein plays a beneficial role in the treatment of PD. The aim of this study is to evaluate whether diacerein promotes the regression of inflammation and reduces bone loss of the alveolar process. Sixty-six male rats will be distributed in 11 groups. PD will be induced by cotton ligature around the upper left first molars. After 7 days, the ligature will be removed; 12 animals will be killed: 6 control animals (CG) and 6 PG animals (periodontitis induced for 7 days). Animals with PD will receive 100 mg/kg bw of diacerein (PDiG) by gavage or physiological solution (PSG) for 7, 15 and 30 days. In each period, 6 animals with no treatment (healthy periodontium) will be killed (control group, CG). After euthanasia, fragments of maxilla containing the molars will be removed and fixed in 4% formaldehyde buffered at pH 7.2 with 0.1 M sodium phosphate. Then, the specimens will be decalcified in 7% EDTA for 60 days and then dehydrated and embedded in paraffin. From each specimen (maxilla), 5 semi-serial sagittal sections (with minimum distance of 100 µm) will be stained with hematoxylin and eosin (HE) for morphological and quantitative analyses of the following parameters: volume density of inflammatory cells and fibroblasts in the mucosa of the interdental gingiva (between the 1st and 2nd molars), and measurement of distances from the junctional epithelium to cementoenamel junction (JE-CEJ) and from CEJ to the crest of the alveolar process (CEJ-AP). The histochemical reaction for tartrate-resistant acid phosphatase (TRAP), used as a marker of osteoclasts, will be performed in 2 non-serial sections of each specimen; the surface of the alveolar process around the 1st molar roots will be measured, and the number of TRAP-positive osteoclasts will be computed. Semi-serial sections will also be submitted to immunohistochemical reactions for detection of IL-1 and MMP-1. In the interdental gingival mucosa, between the 1st and 2nd molars, the numerical density of IL-1- and MMP-1-immunolabeled cells will be obtained from all animals. The quantitative data will be submitted to two-way ANOVA and Tukey post-test (p less than or equal to 0.05).