The Effect of Periodontal Diseases and Cognitive Deficit on Behavioral State, Oxidative Stress Parameters and Alveolar Bone Loss in Rats

Aims: To evaluate the effect of periodontal disease (PD) and cognitive deficit (CD) on behavioral state, oxidative stress parameters, and alveolar bone loss (ABL).

Materials and methods: Fifty male Wistar rats were randomly divided into five groups: control; scopolamine; periodontal disease (PD); PD+scopolamine evaluated by the Morris water maze behavioral test; PD+scopolamine assessed by the inhibitory avoidance behavioral test. PD and CD were, respectively, induced by ligature and scopolamine. Both the maxilla and mandible were morphometrically analyzed for ABL. For all animal groups, the study duration was one month. For the ligated animals, the final evaluation was performed 14 days after the ligature placement. Reduced glutathione (GSH), total sulfhydryl (TS), thiobarbituric acid, catalase, and superoxide essays were assessed in the brain tissues (cortex and hippocampus).

Results: Both groups with induced PD+CD (0.46±0.04mm and 0.47±0.04mm for maze and inhibitory avoidance behavioral tests, respectively) presented a significantly higher ABL in comparison to the group that received only scopolamine (0.22±0.01mm). PD and PD+scopolamine groups presented significantly lower GSH and TS in comparison to the control group. Regarding the memory latency tests, there were no statistically significant differences among groups.

Conclusion: The induction of PD was capable to modulate the CD, decreasing the action of the antioxidant agents in the brain. However, PD was not capable of impairing the short and long-term spatial memory retention behavioral.

Keywords: Alzheimer’s disease; Cognitive dysfunction; Periodontitis; Wistar rats.