RESUMO
BACKGROUND AND OBJECTIVE: Green tea extract exerts a variety of biological effects, including anti-inflammatory activities. However, there has been no report on the effect of green tea extract on loss of attachment, which is an important characteristic of periodontitis. Here, we examined the inhibitory effects of green tea extract on the onset of periodontitis in a rat model. MATERIAL AND METHODS: Rats were immunized intraperitoneally with Escherichia coli lipopolysaccharide (LPS). The LPS group (n = 12) received a topical application of LPS onto the palatal gingival sulcus every 24 h. The green tea extract group (n = 12) received a topical application of LPS mixed with green tea extract, sunphenon BG, every 24 h. The phosphate-buffered saline (PBS) group (n = 6) received a topical application of PBS every 24 h. The levels of anti-LPS immunoglobulin G (IgG) in serum were determined using ELISA. Rats in the LPS and green tea extract groups were killed after the 10th and 20th applications. Rats in the PBS group were killed after the 20th application. Loss of attachment, level of alveolar bone and inflammatory cell infiltration were investigated histopathologically and histometrically. RANKL-positive cells and the formation of immune complexes were evaluated immunohistologically. RESULTS: There was no significant difference in the serum levels of anti-LPS IgG between the LPS group and the green tea extract group. In contrast, loss of attachment, level of alveolar bone, inflammatory cell infiltration and RANKL expression in the green tea extract group were significantly decreased compared with those in the LPS group. CONCLUSION: These findings demonstrate that green tea extract suppresses the onset of loss of attachment and alveolar bone resorption in a rat model of experimental periodontitis.
Assuntos
Anti-Inflamatórios/uso terapêutico , Camellia sinensis , Periodontite/prevenção & controle , Fenóis/uso terapêutico , Extratos Vegetais/uso terapêutico , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Complexo Antígeno-Anticorpo/análise , Tecido Conjuntivo/patologia , Modelos Animais de Doenças , Inserção Epitelial/patologia , Escherichia coli/imunologia , Imunização , Imunoglobulina G/sangue , Lipopolissacarídeos/imunologia , Masculino , Osteoclastos/patologia , Perda da Inserção Periodontal/patologia , Perda da Inserção Periodontal/prevenção & controle , Periodontite/patologia , Fitoterapia , Ligante RANK/análise , Ratos , Ratos Endogâmicos LewRESUMO
The platelet survival time was shortened in stroke-prone spontaneously hypertensive rats (SHRSP) at 10 weeks of age on feeding the regular diet but it was normalized on administering the vitamin E-supplemented diet. Platelet survival time was normal in stroke-resistant spontaneously hypertensive rats (SHRSR) at 10 weeks of age on feeding the regular diet but it was shortened when supplying the vitamin E-free diet. The maximal uptake of 75Se-selenomethionine by platelets was increased in SHRSP at 10 weeks of age on feeding the regular diet. It was further increased in SHRSP on feeding the vitamin E-free diet. On the other hand, the increased maximal uptake of 75Se-selenomethionine by platelets was normalized in SHRSP on feeding both the vitamin E-supplemented diet and the vitamin E-supplemented diet after administering the vitamin E-free diet. Therefore, we concluded that the deficiency of vitamin E brought about the shortening of platelet survival time and enhanced platelet production.