Níveis de β -glucanas no controle da doença periodontal induzida em ratos

Abstract

β-glucans (BGs) are polysaccharides linked by β- (1,3) and β- (1,6) or β- (1,3) and β- (1,4) bonds depending on their origin, such as the cell wall of fungi, algae, bacteria and plants. Plants BGs are known to have metabolic effects such as lowering blood glucose and plasma cholesterol levels, while those derived from fungi and bacteria modulate the immune system and even are used as adjuvants in some vaccines. A previous study of our group showed that the ingestion of BGs isolated from Saccharomices cerevisiae at a dose of 30mg/kg of body weight promoted benefits in the control of alveolar bone resorption (ROA) and metabolic parameters simultaneously in diabetic rats with periodontal disease (DP) induced by ligature. This project aimed to evaluate the effects of treatment with different levels of BGs isolated from Saccharomyces cerevisiae on alveolar bone resorption and biochemical parameters in rats with DP. A total of 30 animals (N = 6 per group) were randomly distributed in five groups that received different doses of BGs (0mg/kg, 10mg/kg, 20mg/kg, 40mg/kg or 80mg/kg) by gavage for 28 days. DP was induced by ligature on the right and left first mandibulars molars with cotton thread on the 14 th day, remaining until the 28 th , when the animals were euthanized. The evaluation of the progression of DP (alveolar bone resorption -ROA) was performed through morphometric analysis (direct using a magnifying glass), histometric (hematoxylin /eosin staining), loss of epithelial junction (PJE) through histometry. Serum levels of total cholesterol (CT), triacylglycerols (TAG) and high density lipoprotein cholesterol (HDL-c) were also evaluated using colorimetric enzyme kits. Low and very lowdensity lipoprotein cholesterol values (LDL-c + VLDL-c) were calculated using the specific formula. The means obtained with each additional dose of BG were submitted to regression analysis and, later, compared to the control (0mg/kg) by Dunnett test at 5%. BG was efficient in reducing ROA in animals treated with 20mg/kg, 40mg/kg and 80mg/kg when compared to the control group (p<0.05). The dose of 54mg/kg was identified as optimal. No significant changes were observed in PJE, levels of CT, TAG, HDL-c, and LDL-c + VLDL-c. It was concluded that doses above 20 mg/kg BG were effective in preventing the progression of PD without significant effects on metabolic parameters.