Quercetin Decreased Alveolar Bone Loss and Apoptosis in Experimentally Induced Periodontitis Model in Wistar Rats

Antiinflamm Antiallergy Agents Med Chem. 2020;19(4):436-448. doi: 10.2174/1871523019666200124114503.

Abstract

Background: Quercetin is a flavonoid which has potent anti-inflammatory, antibacterial, and antioxidant effect. Purpose of this study was to evaluate effects of quercetin on alveolar bone loss and histopathological changes in ligature-induced periodontitis in rats.

Methods: Wistar rats were divided into four experimental groups: non-ligated control (C, n=8) group; periodontitis (P, n=8) group; ligature and low dose quercetin group (75 mg/kg/day quercetin, Q75 group, n=8); ligature and high dose quercetin group (150 mg/kg/day quercetin, Q150 group, n=8). Silk ligatures were placed at gingival margin of lower first molars of mandibular right quadrant. Study duration was 15 days, and animals were sacrificed end of this period. Changes in alveolar bone levels were clinically measured and tissues were immunohistochemically examined, matrix metalloproteinase 8 (MMP 8), inducible nitric oxide synthase (iNOS), tissue inhibitor of metalloproteinase 1 (TIMP 1), Cysteine-aspartic proteases 3 (Caspase 3), and tartrate-resistant acid phosphatase (TRAP) positive osteoclast cells, osteoblast, and neutrophil counts were also determined.

Results and discussion: Alveolar bone loss was highest in P group, and differences among P, Q75, and Q150 groups were significant. Both doses of quercetin decreased TRAP+ osteoclast cells and increased osteoblast cells. Inflammation in P group was also higher than those of C, Q75, and Q150 groups indicating anti-inflammatory effect of quercetin. iNOS, MMP-8, and caspase-3 levels were highest, and TIMP-1 expression was lowest in P group; differences were statistically significant.

Conclusion: Within limits of this study, it can be suggested that quercetin administration may reduce alveolar bone loss by increasing osteoblastic activity, decreasing osteoclastic activity, apoptosis, and inflammation in an experimental model of periodontitis.

Keywords: Anti-inflammatory; MMP-8; antioxidants; experimental periodontitis; iNOS; quercetin.

MeSH terms

  • Alveolar Bone Loss / drug therapy*
  • Alveolar Bone Loss / metabolism
  • Alveolar Bone Loss / pathology
  • Animals
  • Anti-Inflammatory Agents / pharmacology
  • Anti-Inflammatory Agents / therapeutic use*
  • Apoptosis / drug effects
  • Disease Models, Animal
  • Facial Bones / drug effects
  • Facial Bones / metabolism
  • Facial Bones / pathology
  • Female
  • Matrix Metalloproteinase 8 / metabolism
  • Nitric Oxide Synthase Type II / metabolism
  • Osteoblasts / drug effects
  • Osteoclasts / drug effects
  • Periodontitis / drug therapy*
  • Periodontitis / metabolism
  • Periodontitis / pathology
  • Quercetin / pharmacology
  • Quercetin / therapeutic use*
  • Rats, Wistar
  • Tissue Inhibitor of Metalloproteinase-1 / metabolism

Substances

  • Anti-Inflammatory Agents
  • TIMP1 protein, rat
  • Tissue Inhibitor of Metalloproteinase-1
  • Quercetin
  • Nitric Oxide Synthase Type II
  • Nos2 protein, rat
  • Matrix Metalloproteinase 8
  • Mmp8 protein, rat