Green tea and EGCG effects on periodontal disease in diabetic rats: microtomographic and histologic analyses

• Ano de defesa: 2019
• Autor(a) principal: Catanzaro, Daniela Pereira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Antioxidantes; Antioxidants; Catechin; Catequinas; Diabetes Mellitus; Doença Periodontal; Histological Techniques; Microtomografia; Periodontal Disease; Polifenol Oxidase; Polyphenol Oxidase; Técnicas Histológicas; X-Ray Microtomography
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/25/25149/tde-05102021-144942/

Aim: Currently, there is a growing concern among the general population regarding the use of natural products. Many of the ways by which green tea and its polyphenols work have yet to be elucidated. Thus, the objective of this study was to verify the known effects of green tea as an antioxidant, modulator of vascularization during the progression of spontaneous periodontitis in type 1 diabetic rats (T1D). Also, to verify if daily administration of EGCG attenuates bone loss. Alveolar in diabetic rats with periodontal disease induced by silk thread ligation. Material and methods: In article 1, normoglycemic (NG) and T1D Wistar rats were divided into two control groups, which received water (NG-W; n=25 and T1D-W; n=25) and two experimental groups which received green tea (NG-GT; n=25 and T1D-GT; n = 25). Periodontal structures were evaluated by microtomographic and histological analysis. The number of cells imunolabeled for VEGF (NcVEGF +/mm2) and CD31 (NcCD31 + / mm2) as well as the microvessel density (MVD) in the periodontal ligament (PDL) were evaluated. In article 2, 120 Wistar rats were divided into: water treatment (NG-WT, n =20 and T1DWT n =20), daily treatment with EGCG (NG-EGCG, n =20 and T1D-EGCG, n =20) daily saline treatment (NG-Sham, n =20 and T1D-Sham, n =20). Periodontitis was induced by a ligature placed around the right lower first molar 7 days after initiation of treatment. After 0, 7, 14 and 21 days, the scores of degrees of periodontal disease, PBL and BV / TV were analyzed. Results: In article 1, there was a severe degree of periodontitis with greater reduction in bone volume and periodontal bone level. In T1D-GT, green tea maintained MVD, NcCD31 + / mm2 and NcVEGF + / mm2 in LDP, being similar to normoglycemic groups. Clinically, in T1D-GT rats, green tea reduced dental plaque accumulation and the degree of periodontitis when compared to T1DW. In article 2, gradual increase of total PBL was observed in all experimental groups up to 14 days. At 21 days, total PBL of T1D-WT and T1D-Sham increased by an average of 132%, while in NG-WT, NG-Sham, NG-EGCG and T1D-EGCG remained similar. Between 14 and 21 days, a significant increase (p> 0.01) of interradicular BV / VT was observed in the normoglycemic and T1D-EGCG groups. T1D-EGCG PD scores did not show statistical differences when compared to NG groups. Conclusion: Daily consumption of green tea has a therapeutic effect on diabetic vascular disorder in the PDL and the progression of periodontitis in the long-term of hyperglycaemia in T1D rats, whereas daily consumption of EGCG has therapeutic effect on periodontal disease in hyperglycemic condition, reducing then the degree and severity of the disease.