Systemic rosiglitazone administration leads to cementocytes apoptosis in wild type mice

It has been shown that a class of drugs for diabetes control, the thiazolidinediones, leads to increased apoptosis in osteocytes. Considering the correlations between osteocytes and cementocytes, the aim of this study was to demonstrate the apoptosis on cementocytes of wild type mice that had received rosiglitazone. Twenty-four male C57BL/6 mice were divided into 3 groups: 1 control, which received only the vehicle administration via oral for 1 week (PBS+DMSO 10%) and other two groups, which received 10 mg/kg of RGZ+PBS+DMSO 10% for 1 or 2 weeks, respectively. Upon completion of the time courses, mice were killed by CO2 and the mandibles were dissected and subjected to routine histotechnical processing. The sections were analyzed through transferase-mediated dUTP nick-end labeling (TUNEL) and 4’,6- diamidino-2-phenylindole (DAPI) staining of nuclear morphology (α=0.05). Control group showed significantly lower apoptotic cells/total cells ratio when compared to the experimental groups with TUNEL and DAPI methods (p=0.010 and 0.004, respectively). TUNEL method showed approximately 20% TUNEL-positive cementocytes in control and 26% in both experimental groups, while the DAPI technique showed approximately 32% of DAPI-positive cementocytes in control and 38% to 40% in experimental groups. The rosiglitazone systemic administration can lead to cementocytes apoptosis in mice. Despite the differences between the experimental and control groups, the death of cementocytes occurred as a physiological phenomenon, important in understanding the role of these cells in periodontal tissue.