Pré-condicionamento e tratamento com misturas de óleos de ômega-3, 6 e 9 sobre a inflamação e a reabsorção óssea na doença periodontal experimental

Abstract

CAMILA PINHO PESSOA DE VASCONCELOS. Strictu Sensu Post-graduation in Surgery, Department of Surgery, School of Medicine, Federal University of Ceara (Degree of Master of Surgery). Abril, 2013. Advisor: Prof. Paulo Roberto Leitão de Vasconcelos.

Periodontitis, a chronic inflammatory disease that results from extension of the inflammatory process initiated in the gingiva to the supporting tissues of the teeth, is characterized by bleeding gums, periodontal pocket formation, destruction of connective tissue and alveolar bone resorption and may lead to loss tooth. Omega-3 (ω-3) and omega-9 (ω-9) unsaturated fatty acids are anti-inflammatory and antioxidant, while omega-6 (ω-6) fatty acids have proinflammatory properties. The aim of this study was to investigate the anti-inflammatory and the bone protective effect of preconditioning with fatty acids mixes (ω-3, ω-6 and ω-9) containing high ratio of ω-9/ω-6 and low ratio of ω-6/ω-3 on the experimental periodontal disease (EPD). EPD was induced by passing a 3.0 nylon thread around the upper left second molar in Wistar male rats. The animals were distributed into two groups: control and treated. Control group was subdivided in 3 subgroups: NORMAL, whose animals were not submitted to DPE and received no treatment, SALINE and Isolipidic (ISO), whose animals received saline or a isolipid solution mixture containing ω-6/ω-3 oils (8:1 ratio) and ω-9/ω-6 (0.4:1 ratio). Treated group included 3 subgroups: Mix 1, Mix 2 and Mix 3. The animals received anti-inflammatory and antioxidant mixtures of ω-6/ω-3 (1.4:1 ratio) and ω-9/ω-6 (3.4:1 ratio), differing only in source of ω-3: Mix 1 containing α-linolenic acid; Mix 2, composed of α-linolenic, docosahexaenoic and eicosapentaenoic acids and Mix 3 containing α-linolenic, docosahexaenoic. In both groups (control and treated) the administration of oil/saline solution was performed daily by gavage, starting 7 days before the periodontitis induction until euthanasia on 11th day after surgery. Some animals was sacrificed in the sixth hour after surgery for gingival myeloperoxidase (MPO). The parameters assessed were alveolar bone loss (ABL), histological analysis, myeloperoxidase (MPO) and immunohistochemistry for inducible nitric oxide syntase (iNOS) and nuclear factor-κB (NF-κB). Experimental periodontitis caused significant increases in BLI and in inflammatory cell infiltrate in the gingival tissue and periodontal collagen disarrangement. Furthermore, was identified the presence of the epithelial cell rests of Malassez (ERM) in the proximity of the cementum and alveolar bone. Mix1, which ω-3 is derived from ALA (flaxseed oil) was able to reduce the BLI and the inflammatory infiltrate in comparison with the SALINE e ISO. Mix 1 also decreased the demarcation to iNOS and NF-κB. These results show that flaxseed oil intake has anti-inflammatory and bone protective effect on the experimental periodontal disease in Wistar rats.