Osteopontin Promotes Bone Destruction in Periapical Periodontitis by Activating the NF-κB Pathway

Abstract

Background/Aims: Periapical periodontitis is caused by bacterial infection and results in both one destruction and tooth loss. Osteopontin (OPN) is a secreted phosphorylated glycoprotein that participates in bone metabolism. Methods: Thirty-three patients with chronic periapical periodontitis and 10 patients who had undergone the orthodontic removal of healthy tooth tissue (control) at the periodontal ligament were investigated, and an animal model of mouse periapical periodontitis was established for an in vivo analysis. The relationship between OPN and bone destruction during periapical periodontitis was analyzed. Osteoblasts and osteoclasts were cultured in vitro and treated with lipopolysaccharide. An inhibitor of NF-κB was used to pretreat the transfected cells. Results: OPN increased osteoclast proliferation and differentiation, but reduced osteoblasts proliferation and differentiation. OPN activated the NF-κB pathway during periapical periodontitis and accelerated the transfer and phosphorylation of P65 from the cytoplasm to the nucleus. Conclusion: This study demonstrated that OPN played important roles in the progression of periapical periodontitis, and a dual role in bone metabolism during periapical periodontitis, linking osteoclasts and osteoblasts. The underlying mechanism may be related to the NF-κB pathway.

Radiographic and Immunohistochemical Evaluation of Root Canal Treatment Using Different Irrigation Systems

“…OPN and TNF-α production were more intense in the teeth with apical periodontitis without treatment, but it was not possible to find a statistically significant difference between the groups submitted to the different irrigation protocols. In bone tissue, the role of osteopontin is controversial, since the molecule can function as an osteoclast anchoring protein by increasing bone catabolism (10,12,34) or as a protective factor in the recruitment of phagocytes to polymicrobial infection (35). Significantly higher levels of TNF-α have also been observed in more active lesions, characterized by increased expression of the activator receptor ligand of the nuclear factor kappa B (8).…”

“…The recruitment of inflammatory cells to the apical and periapical regions is directed by the release of chemotactic factors, such as the cytokines interleukin-1α (IL-1α) and tumor necrosis factor-α (TNF-α) (6,7), which locally induce inflammation and bone tissue resorption (6)(7)(8)(9). Osteopontin (OPN) is a phosphoprotein secreted by T lymphocytes and macrophages, important for both the regulation of the immune response -recruitment of leukocytes and activation of dendritic cells -and mediation of bone resorption (10)(11)(12).…”

Evaluation of Systemic Inflammation Parameters in Dogs with Periodontitis

“…Dong et al [35] evaluated the role of osteopontin on bone metabolism in periodontal diseases. They determined a decrease in osteoblast activity by osteoclast differentiation and proliferation following periodontitis progress.…”

Bone Turnover Markers in Chronic Periodontitis: A Literature Review

“…Osteopontin is a glycoprotein found in non-mineralized tissues, primarily renal, endothelial cells, and epithelial cells. Osteopontin plays a dual function both in bone mineralization and bone resorption [45]. Osteopontin enhances dentine formation during the bone remodeling process and has been implicated in the recruitment of polymorphonuclear cells in response to infections [46].…”