内源性配体SLURP1经α7亚型烟碱型乙酰胆碱受体介导调控乳牙牙髓干细胞破骨能力的研究

SLURP1 regulates the osteoclastogenic differentiation of stem cells from human exfoliated deciduous teeth through α7 nAChR

目的:初步探讨α7亚型烟碱型乙酰胆碱受体(α7 nAChR)及其内源性配体SLURP1在乳牙生理性根吸收过程中调控破骨细胞分化成熟的可能作用。方法:分离培养并优选乳牙生理性根吸收不同时期乳牙牙髓干细胞(SHEDs)及恒牙牙髓干细胞(DPSCs),经检测鉴定后,分别采用实时定量PCR、免疫荧光染色及半定量光密度分析技术检测各组细胞中α7 nAChR基因及蛋白的表达差异;实时定量PCR检测各组细胞中SLURP1、经典成骨/破骨相关因子RANKL、OPG基因的表达差异,并进行统计学分析。结果:乳牙牙根吸收中期及晚期的SHEDs中α7 nAChR基因和蛋白的表达水平显著高于乳牙牙根稳定期SHEDs与恒牙DPSCs(P<0.05);SLURP1基因表达水平以乳牙牙根吸收中期最高,晚期次之,恒牙再次之,乳牙牙根稳定期最低,各组间P<0.05。RANKL/OPG比值与SLURP1基因表达趋势一致(P<0.05)。结论:SLURP1与乳牙牙髓干细胞膜上的α7 nAChR结合后,可通过调节RANKL/OPG的表达比例而影响乳牙牙髓干细胞的破骨能力。

AIM： To investigate the role of cO nAChR and SLURP1 in differentiation and maturation of osteoclasts in the process of deciduous teeth physiologiieal root resorption. METHODS： SHEDs from different stages of deciduous teeth physiological root resorption and DPSCs from permanant teeth were isolated, cultivated and purified by enzyme digestion method and limiting dilution assay. The cells were identified by cellular morphology, growth pattern, osteogenic induction, adipogenic differentiation and flow cytometry analysis. Gene and protein expression of α7 nAChR was detected by quantitative real-time PCR, immunofluorescence and semiquantitative optical density analysis. SLURP1 and RANKL/OPG gene expression was detected by quantitative real-time PCR. RESULTS ： Gene and protein expression of α7 nAChR in SHEDs from the middle and the final stage of physiological root resorption was higher than those from the stable stage and higher than DPSCs（P 〈 0.05）. SLURP1 expression was the highest in the middle stage, followed by the final stage, permanent teeth and the stable stage of deciduous teeth. （ P 〈 0.05 ）. RANKL/OPG ratio showed the similar expression tendency to SLURP1 expression. CONCLUSION： SLURP1 may regulate the osteoclastogenic differentiation of stem cells from human exfoliated deciduous teeth by binding to α7 nAChR.