Study On The Correlation Between IL-33 Expression In Bone Resorption Of Human Chronic Apical Periodontitis

Objective To observe the expression of IL-33 in human chronic apical periodontitis,and to analyze its relationship with the expression of OPG and RANKL,and to prove that IL-33 is associated with chronic apical periodontitis,and further to explore the role of IL-33 in the bone resorption mechanism of chronic apical periodontitis.MethodsThe samples were admitted from the Department of Stomatology,Affiliated Hospital of Inner Mongolia Medical University from May to December 2017.The effected teeth that had been diagnosed with chronic apical periodontitis and had been removed without treatment value,Taking 30 cases of periapical lesions of the affected teeth as experimental group.At the same time,30 cases ofhealthy periapical tissue of patients with orthodontic reduction were extracted as control group.The expression of IL-33,OPGandRANKLproteins was observed by histologyand immuno-histochemistry.Real-time PCR(RT-PCR)was used to detect the expression of IL-33,OPG and RANKL mRNA,and the correlation between IL-33 and OPG,RANKL was analyzed.Results At the histological level,a large number of inflammatory cell infiltration was observed in the periapical lesions,mainly lymphocytes ? plasma cells ?macrophages and small amounts of neutrophils.And fibroblasts and new capillaries were also observed.Immunohistochemistry showed that the positive expression of IL-33 in human periapical lesions was significantly higher than that in healthy control group(P<0.05).And IL-33-positive expression was mainly in endothelial cells,epithelial cells and inflammatory cells;OPG-positive expression was significantly higher in healthy control group than in chronic apical periodontitis(P<0.05),which was mainly in endothelial cells and epithelial cells of healthy periapical tissues and inflammatory cells of periapical lesions.The expression of RANKL in human chronic apical periodontitis was significantly higher than that in healthy control group(P<0.05),which was mainly in inflammatory cells.RT-PCR results showed that the mRNA expression of IL-33 in the periapical lesions was significantly higher than that in the healthy periapical tissues;the mRNA expression of OPG in healthy periapical tissues was significantly higher than in the periapical lesions;the mRNA expression of RANKL in the periapical lesions was significantly higher than that in healthy periapical tissues;Correlation analysis showed that the expression level of IL-33 mRNA was positively correlated with OPG mRNA and negatively correlated with RANKL.(P<0.05)ConclusionIL-33 was involved in bone resorption of human chronic apical periodontitis.At the same time,we believe that IL-33 may play a protective role in the bone resorption of chronic apical periodontitis by promoting the expression of OPG and inhibiting the expression of RANKL,but its role in the pathogenesis of disease,development,and outcome still needs further to study.