The Expression And Mechanism Of Cyclophilin A In Periodontitis

Periodontitis is one of the main diseases of human,the prevalence of periodontitis is high among adults in China.It is urgent to prevent the periodontitis.Periodontal disease is caused by bacteria and their metabolites.The pathogenic factors can destroy periodontal tissues and induce the immune regulatory response of the host.The host’s immune response also plays an important role in the process of periodontitis.Cyclophilin A(CyPA),also known as cyclosporin a binding protein,is the major cytoplasmic binding protein of cyclosporin A(CsA).CyPA is believed to have many roles in kinds of biological conditions including protein folding,trafficking,and T-cell activation.Recent studies have shown that extracellular CyPA has chemotactic effects on leukocytes,monocytes and lymphocytes.The research on CyPA chemotaxis has become a new research hotspot.CyPA in inflamed gingival tissues was significantly higher than that in healthy gingival tissue.It mainly located in inflammatory infiltrating cells and infiltrating gingival connective tissue.These data suggest that CyPA is associated with the inflammatory infiltration and alveolar bone destruction of periodontitis.CD68+ is a protein highly specifically expressed by cells in monocyte lineages and macrophages.The expression level of CD68+ inflammatory cells in periodontal tissues will largely determine the level of periodontal bone destruction and affect the prognosis of periodontitis.The relationship between CyPA and CD68+inflammatory cells and the role of this relationship in periodontitis still need further study.Part Ⅰ and Part Ⅱ Cyclophilin A increases CD68+ cell infiltration in rat experimental periodontitis[Objectives]to observe the expression and distribution of CyPA and CD68+ cells in the histopathogenesis of rat ligation-induced experimental periodontitis,and assess the role of CyPA in CD68+ cell infltration in rat experimental periodontitis.[Methods]CyPA expression in gingival tissues was detected by Western blotting.Immunohistochemistry was applied for CyPA and CD68+ cells distribution.For further certifying the role of CyPA in CD68+ cell infltration,the right mandibular frst molar received 0.1 μM CyPA locally by gingival injection every 2 days(L + C group),while the left mandibular first molar received saline as a control group(L group).The number of CD68+ cells in the experimental periodontitis was observed by immunohistochemistry.Alveolar bone destruction was assessed by Micro-computerized tomography(Micro-CT).Osteoclast was observed through TRAP staining.Nuclear factor NF-κB,phospho-p65(p-p65)and phosphor-IκBa(p-IκBα)expressions were detected to investigate NF-κB activation.[Results]CyPA showed an increasing trend at 1-6 weeks after ligation.CyPA and CD68+cells were present in the gingival inflammatory infltration,and participated in alveolar bone destruction.In the L+C group,the number of CD68+ cells was increased compared with the L group,and greater alveolar bone destruction was observed.NF-κB,p-p65 and p-IκBα expressions were upregulated in the L + C group compared with the L group indicating NF-κB activation.CyPA increases CD68+cell infltration in rat experimental periodontitis,suggesting CyPA might be an anti-inflammatory therapeutic target.Part Ⅲ Elevated expression of Cyclophilin A in human periodontitis[Objectives]To elucidate the correlation between cyclophilin A(CypA)and inflammatory infiltrating cells in human periodontitis.[Methods]Western blotting,immunohistochemistry,and immunofluorescence were performed to detect the expression level of CypA in gingival tissues of human periodontitis.Healthy gingival tissues were chosen as a control.[Results]Immunohistochemistry and immunofluorescence identified that the positive-expressed CypA was localized in the infiltrating cells.CD3+,CD^+,CD22+,and CD68+ cells all could be observed in the CypA-positive infiltrating cells.The NF-kB pathway was activated in human periodontitis.Immunofluorescence double labeling results further confirmed that CyPA is closely related to CD68+inflammatory cells.[Conclusions]CypA is involved in leukocyte attraction in the periodontal inflammatory response.These efforts not only highlight the pathogenesis of human periodontitis,but also signify CypA as a potential target for anti-inflammatory therapeutics.