Periodontitis can lead to an Initial Process of Neuroinflammation in Experimental Models
Jossinelma Camargo Gomes
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
Bianca Caroline Custodio dos Santos
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
Iohana Fiorese Choptian
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
Maria Luiza Serradourada Wutzke
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
Leonardo Maso Nassar
School of Economics, Business Administration and Accounting at Ribeirão Preto of the University of São Paulo (FEA-RP/USP), Ribeirão Preto, São Paulo, Brazil.
Sara Cristina Sagae Schneider
Department of Biological Sciences, Western Parana State University, Cascavel, Paraná, Brazil.
Ivo Ilvan Kerppers
Department of Physiotherapy, Midwestern Parana State University, Guarapuava, Paraná, Brazil.
Guilherme Ribas Taques
Department of Medicine, Midwestern Parana State University, Guarapuava, Paraná, Brazil.
Patricia Oehlmeyer Nassar
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
Carlos Augusto Nassar *
State University of Western Parana (UNIOESTE), Cascavel, Parana, Brazil.
*Author to whom correspondence should be addressed.
Abstract
Introduction: Recent evidence shows a possible causal relationship between periodontitis and neurodegenerative diseases. Changes in the hippocampus can result in reduced cognitive functions such as behaviors associated with memory and emotions.
Objectives: Evaluate the influence of ligature-induced experimental periodontitis on the inflammation of the hippocampus of rats.
Materials and Methods: Twenty male Wistar rats, divided into Control Group (GC) and Periodontal Disease Group (GDP). GDP was induced to experimental periodontitis by placing a ligature on the lower molars for 30 days. The study performed three behavioral tests during the experiment in two stages: before and after the induction of periodontitis; at the end, the rats underwent euthanasia and the collection of the hippocampus (histological and immunological analysis) and hemimandibles (histological and radiographic analysis), with subsequent performance of Student's T-tests and Two-Way ANOVA to analyze the results.
Results: GDP showed a higher level of anxiety, less habituation and reduced time to explore the new object compared to GC (p<0.05). Besides, GDP had a lower number of osteocytes and osteoblasts, and higher osteoclastic activity, as well as more significant alveolar bone loss compared to GC (p<0.05). Senile plaques were noted in the hippocampus in addition to positive beta-amyloid, tau, and CD68 markings on GDP.
Conclusions: Therefore, it can be concluded that periodontitis triggered the presence of senile plaques, beta-amyloid, tau, and CD68 markings, which, together, manifested an initial neuroinflammation process in these animals. Clinical Relevance: Periodontitis can be a risk factor in neuroinflammation process
Keywords: Periodontitis, alveolar bone, inflammation, neuroinflammation, hippocampus