Long-term evaluation of oral gavage with periodontopathogens or ligature induction of experimental periodontal disease in mice

Author(s)

de Molon, Rafael Scaf ^{[1, 2]} ; Mascarenhas, Vinicius Ibiapina ^[1] ; de Avila, Erica Dorigatti ^[3] ; Finoti, Livia Sertori ^[1] ; Toffoli, Gustavo Boze ^[1] ; Palomari Spolidorio, Denise Madalena ^[4] ; Scarel-Caminaga, Raquel Mantuaneli ^[5] ; Tetradis, Sotirios ^{[6, 2]} ; Cirelli, Joni Augusto ^{[1, 7]}

Affiliation

^[1] Sao Paulo State Univ, Sch Dent Araraquara, Dept Diag & Surg, Rua Humaita 1680, BR-14801903 Araraquara, SP - Brazil

^[2] UCLA Sch Dent, Div Diagnost & Surg Sci, 10833 Le Conte Ave, Los Angeles, CA 90095 - USA

^[3] Sao Paulo State Univ, Dept Dent Mat & Prosthodont, Sch Dent Araraquara, Rua Humaita 1680, BR-14801903 Araraquara, SP - Brazil

^[4] Sao Paulo State Univ, Sch Dent Araraquara, Dept Physiol & Pathol, Rua Humaita 1680, BR-14801903 Araraquara, SP - Brazil

^[5] Sao Paulo State Univ, Sch Dent Araraquara, Dept Morphol, Rua Humaita 1680, BR-14801903 Araraquara, SP - Brazil

^[6] Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90095 - USA

^[7] Univ Estadual Paulista UNESP, Sch Dent Araraquara, Rua Humaita1680, BR-14801903 Araraquara, SP - Brazil

• Document type: Journal article
• Source: CLINICAL ORAL INVESTIGATIONS; v. 20, n. 6, p. 1203-1216, JUL 2016.
• Web of Science Citations: 14

Abstract

To evaluate in long-term periods the destruction of periodontal tissues and bacterial colonization induced by oral gavage with periodontopathogens or ligature experimental periodontal disease models. Forty-eight C57BL/6 J mice were divided into four groups: group C: negative control; group L: ligature; group G-Pg: oral gavage with Porphyromonas gingivalis; and group G-PgFn: oral gavage with Porphyromonas gingivalis associated with Fusobacterium nucleatum. Mice were infected by oral gavage five times in 2-day intervals. After 45 and 60 days, animals were sacrificed and the immune-inflammatory response in the periodontal tissue was assessed by stereometric analysis. The alveolar bone loss was evaluated by live microcomputed tomography and histometric analysis. qPCR was used to confirm the bacterial colonization in all the groups. Data were analyzed using the Kruskal-Wallis, Wilcoxon, and ANOVA tests, at 5 % of significance level. Ligature model induced inflammation and bone resorption characterized by increased number of inflammatory cells and decreased number of fibroblasts, followed by advanced alveolar bone loss at 45 and 60 days (p < 0.05). Bacterial colonization in groups G-Pg and G-PgFn was confirmed by qPCR but inflammation and bone resorption were not observed (p < 0.05). The ligature model but not the oral gavage models were effective to induce inflammation and bone loss in long-term periods. Pg colonization was observed in all models of experimental periodontal disease induction, independent of tissue alterations. These mice models of periodontitis validates, compliments, and enhances published PD models that utilize ligature or oral gavage and supports the importance of a successful colonization of a susceptible host, a bacterial invasion into vulnerable tissue, and host-bacterial interactions that lead to tissue destruction. The ligature model was an effective approach to induce inflammation and bone loss similar to human periodontitis, but the oral gavage models were not efficient in inducing periodontal inflammation and tissue destruction in the conditions studied. Ligature models can provide a basis for future interventional studies that contribute to the understanding of the disease pathogenesis and the complex host response to microbial challenge. (AU)

• FAPESP's process: 12/11860-8 - Periodontal tissues alterations in two models of periodontal disease induction in mice: histological and computed microtomography analysis
• Grantee: Gustavo Boze Toffoli
• Support Opportunities: Scholarships in Brazil - Scientific Initiation