Role of the Btk-PLC2 Signaling Pathway in the Bone Destruction of Apical Periodontitis.

Chronic apical periodontitis is characterized by alveolar bone absorption in the apical region and is the result of the participation of various inflammatory mediators. Studies have shown that the Bruton tyrosine kinase- (Btk-) phospholipase C2 (PLC2) signaling pathway plays an important role in bone absorption, but it is unknown whether it plays a role in apical periodontitis bone destruction. Therefore, this study verified the role of Btk and PLC2 in bone resorption of apical periodontitis by and experiments. In the experiment, a mice model of apical periodontitis was established; apical bone resorption was confirmed by the numbers of osteoclasts and HE staining. Btk, PLC2, and nuclear factor of activated T-cells 1 (NFATc-1) were detected by immunohistochemical staining. In the experiment, lipopolysaccharides (LPS) were used to stimulate osteoclast precursor cell RAW264.7 to establish an inflammatory microenvironment and detect osteoclast differentiation. By silencing Btk, the expression of Btk, PLC2, and NFATc-1 was detected by real-time qPCR and Western blot, and osteoclastogenesis was detected by enzyme histochemical staining to further confirm the role of Btk in bone resorption. It was found that the expression of Btk, PLC2, and NFATc-1 changed significantly with the progression of inflammation and bone destruction, indicating that Btk and PLC2 may be involved in the progression of inflammation in apical periodontitis and bone absorption. experiments confirmed that the differentiation of osteoclasts and the expression of PLC2 and NFATc-1 were significantly inhibited after silencing Btk expression, but osteoclast precursor cells could be differentiated due to the proinflammatory factor lipopolysaccharide. This study demonstrates that Btk and PLC2 are key factors involved in the apical inflammatory response and bone destruction.