Periodontal changes and in alveolar bone turnover markers during orthodontic tooth movement in type 2 diabetic rats treated with metformin: histomorphometric and immunohistochemical analyses

Abstract

According to the Brazilian Society of Diabetes (2016) it is undergoing an epidemic diabetes mellitus (DM), with an approach of 471 million people in 2035. The DM type 2 (DM2) is related to insulin resistance and obesity and they represent about 90% of the total diabetics. Metabolic changes in DM2 besides leading to cardiovascular, neurological and kidney diseases also lead to osteoporosis and fractures. In a previous study we found that the high-fat diet in rats promotes obesity and it results in decreased alveolar bone density. During experimental orthodontic movement, by micro-ct we have observed that the DM2 animals had inadequate tooth movement associated with severe bone loss, whereas in rats treated with metformin the pattern of movement was similar to normoglycemic. Corroborating this findings in the current work we will evaluate by histomorphometry changes in the periodontal ligament and by immunohistochemistry we will quantify the number of labeled cells per mm2 of the key molecules involved in the alveolar bone remodeling process as formation, activation and survival of osteoclasts (TRAP +, TNF-± , RANKL, OPG) and differentiation and activity of osteoblasts (Runx-2, OC and ALP). Also we will quantify the advanced glycation end products receptors RAGE related to the diabetic state. The data will be submitted to two way analysis of variance (ANOVA).