Anti-inflammatory and bone antiresorptive effects of Punica granatum L. combined or not to low level laser irradiation on ligature-induced bone loss in rats

Periodontitis is a chronic infectious inflammatory disease. P. granatum (PNG) and low level laser irradiation (LLLI) have demonstrated anti-inflammatory properties and antioxidants. The aim of this study was to evaluate the anti-inflammatory and bone antiresorptive activities of PNG combined or not with LLLI in ligature-induced periodontitis in rats. Periodontitis was induced in 72 rats by inserting a nylon-3.0 around the left upper second molar. The contralateral hemimaxila was used as control. Groups of 6 animals received saline 0.9% (SAL), SAL+LLLI 4 J/cm2, PNG [60, 180, 540 (mg/kg)] or PNG 540 mg/kg+LLLI 4 J/cm2. The low intensity laser GaAlAs was applied immediately after surgery, while PNG was administered by gavage daily until day 11, when the animals were killed. The jaws were removed and processed for macroscopic, histometric, histological and immunohistochemical staining for TRAP. Gingival tissue samples were obtained to evaluate the activity of myeloperoxidase (MPO). Blood samples were collected for measurement of serum bone alkaline phosphatase (BALP), leukograms and analysis of liver and kidney function. Additionally, indexes of liver and kidney were performed. Rats were weighted daily. Periodontitis induction caused intense alveolar bone loss (ABL), reduction of BALP, cementum and periodontal ligament destructions, and intense leukocyte infiltration. Systemically, periodontitis induced leukocytosis and and did not alter hepatic transaminases, urea or creatinine serum levels, or liver and kidney indexes. The ABL was prevented by PNG (60= 34%, 180= 34%, 540= 42%), SAL+LLLI= 31% e PNG 540+LLLI= 48% (p0.05), the combined treatment with PNG 540+LLLI caused an increase on BALP serum levels (74.2 ± 5.4 U/l), when compared to SAL (44.9 ± 3.0 U/l) (p0.05) and all groups prevented (p0,05), PNG 540+ILBI causou um aumento significante nos níveis séricos de FAO (74,2 ± 5,4 U/l), quando comparado ao SAL (44,9 ± 3,0 U/l) (p0,05), e todos os grupos preveniram (p