牙龈卟啉单胞菌上调钙结合蛋白1促进牙龈上皮细胞增殖

Porphyromonas gingivalis upregulates calbindin 1 and thus promotes the proliferation of gingival epithelial cells

目的探究钙结合蛋白1在牙龈卟啉单胞菌(P.gingivalis)影响牙龈上皮细胞增殖和凋亡中的作用。方法P.gingivalis感染CA9-22细胞,在感染24 h后,采用实时荧光定量聚合酶链反应、免疫印迹法和免疫荧光法检测钙结合蛋白1(CALB1)的表达。通过RNA干扰法抑制CALB1表达,BrdU分析检测细胞增殖,Caspase 3活性测定检测细胞凋亡,免疫印迹法检测MDM2和p53的表达。结果P.gingivalis感染促进CA9-22细胞中CALB1的表达,并且CALB1的表达具有感染复数依赖性。CALB1促进CA9-22细胞增殖,上调细胞内MDM2的表达,同时抑制p53的表达。下调CALB1表达不影响P.gingivalis感染对CA9-22凋亡的抑制作用。结论P.gingivalis感染可通过上调CALB1表达促进CA9-22细胞增殖,其机制可能与影响MDM2-p53有关。

Objective This study aims to investigate the effect of calbindin 1 on the proliferation and apoptosis of gingival epithelial cells affected by Porphyromonas gingivalis(P.gingivalis)in vitro.Methods A model of P.gingivalis infecting CA9-22 was established in vitro.At 24 h after infection,the expression of calbindin 1(CALB1)was detected by real-time fluorescent quantitative polymerase chain reaction,Western blot,and immunofluorescence analyses.The expression of CALB1 was further inhibited by RNA interference.Cell proliferation was detected by BrdU analysis,and cell apoptosis was detected by caspase 3 activity.The expression of MDM2 and p53 was detected by Western blot analysis.Results P.gingivalis infection upregulated the expression of CALB1 in CA9-22 cells with multiplicity-dependent manner.CALB1 promoted the proliferation of CA9-22 cells,increased the expression of MDM2,and inhibited the expression of p53.Inhibiting CALB1 expression did not affect the inhibitory effect of P.gingivalis infection on CA9-22 apoptosis.Conclusion P.gingivalis infection can promote the proliferation of CA9-22 cells by increasing CALB1 expression.The related mechanism may be associated with MDM2-p53.