Effect of environmental tobacco smoke on COX‐2 and SHP‐2 expression in a periodontitis rat model

Abstract

Objectives To investigate the effects of environmental tobacco smoke (ETS) on the inflammatory process of periodontitis by evaluating bone loss and the expression of cyclooxygenase‐2 (COX‐2) and Src homology phosphotyrosine phosphatase 2 (SHP‐2). Materials and Methods Eighty 6‐month‐old male SD rats were randomized into four groups (10 rats/group/per time point): (a) normal group, (b) ETS group, (c) ligature‐induced periodontitis group, and (d) ligature‐induced periodontitis + ETS group. After treatment with ligature and/or ETS for 8 and 12 weeks, the levels of alveolar bone resorption and the expressions of COX‐2 and SHP‐2 in periodontal tissue were analyzed using histology and immunohistochemistry. Results The ligature‐induced periodontitis group displayed increased bone resorption and elevated expression of COX‐2 and SHP‐2 in periodontal tissues compared to the normal and ETS groups at 8 and 12 weeks. Furthermore, bone resorption and COX‐2 and SHP‐2 levels in the ligature‐induced periodontitis + ETS group were significantly increased compared to those in the normal and ligature‐induced periodontitis groups at both 8 and 12 weeks. Conclusion Environmental tobacco smoke increased alveolar bone loss in periodontitis with enhanced expression of COX‐2 and SHP‐2 in periodontal tissues. Further investigation is needed to explore the role of COX‐2 and SHP‐2 in ETS‐associated periodontitis.

Correlation of exposure to environmental tobacco smoke and periodontitis in passive smokers; a systematic review

“…Periodontitis is a common chronic inflammatory disease with a multifactorial etiology. It is caused by gram-negative anaerobic bacteria and is influenced by a number of factors such as an immunocompromised state and smoking (25).…”

“Medicine food homology” plants promote periodontal health: antimicrobial, anti-inflammatory, and inhibition of bone resorption

“…Matrix metalloproteinase (MMP) is a family of zinc-dependent endopeptidases whose main function is to cleave extracellular matrix proteins, reshape tissues and degrade extracellular matrix under physiological and pathological conditions, and is considered to be an important substance involved in periodontal tissue collapse and inflammatory response during the development of periodontitis ( 142 ). Cyclooxygenase-2 (COX-2) promotes the disease process of periodontitis by mediating the inflammatory process in periodontal tissues ( 143 ). Nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream anti-invertases, such as heme oxygenase-1 (HO-1), are essential in resisting cellular oxidative stress and down-regulating the inflammatory response ( 144 ).…”