恒牙与乳牙牙髓干细胞增殖及唾液腺分泌相关分子基因表达比较

The dental pulp stem cell proliferation and gene expression of salivary gland secretion related molecules in permanent teeth and milk teeth

目的比较恒牙与乳牙牙髓干细胞增殖及唾液腺分泌相关分子基因表达。方法选择6~11岁脱落乳牙10颗与18~25岁因正畸拔除的完整磨牙10颗,提取牙髓干细胞,纯化扩增,选择第6代与第8代细胞分析牙髓干细胞增殖情况,测定牙髓干细胞标记物,测定唾液腺分泌相关分子MR1、MR3、APQ5、β1-AR、β2-AR、α-淀粉酶、黏蛋白5B基因表达水平。结果第6代乳牙、第8代乳牙、第6代恒牙、第8代恒牙牙髓干细胞增殖差异无统计学意义(P>0.05),均在第9天达到平台期。第6代乳牙、第8代乳牙、第6代恒牙、第8代恒牙牙髓干细胞标志物CD44、CD29、CD90、CD73、CD146、CD105表达水平差异无统计学意义(P>0.05)。MR1在第6代恒牙牙髓干细胞中表达水平最高,其次为第6代乳牙,第8代乳牙与第8代恒牙表达水平相当。MR3在4组中的表达水平差异无统计学意义(P>0.05)。AQP5在第6代乳牙、第8代乳牙、第6带恒牙中的表达水平相似,显著高于第8代恒牙(P<0.05)。β1-AR在第6代恒牙中的表达水平最高,显著高于其他3组(P<0.05)。β2-AR在第6代乳牙中的表达水平最高,其次为第6代恒牙,第8代乳牙表达水平最低,显著低于其他3组(P<0.05)。α-淀粉酶在第6代恒牙中表达水平最高,其次为第8代恒牙,显著高于第6代乳牙与第8代恒牙,差异有统计学意义(P<0.05)。黏蛋白5B在第6代恒牙中表达水平最高,其次为第6代乳牙,第8代乳牙,第8代恒牙的表达水平最低,差异有统计学意义(P<0.05)。结论恒牙与乳牙牙髓干细胞生长情况与干细胞标记物没有显著差异;第6代与第8代乳牙及恒牙表达不同水平的唾液腺分泌相关分子基因。

Objective To compare the stem cell proliferation and salivary gland secretion-related molecular gene expression in dental pulp stem cells(DPSCs)between permanent teeth and deciduous teeth.Methods Ten deciduous milk teeth of 6-to 11-year-old children and 10 complete molars of 18-to 25-year-old people due to orthodontic extraction were selected.The DPSCs were extracted for purification and amplification.The cells of 6th and 8th generation teeth were selected to analyze the proliferation of DPSCs,and the markers of DPSCs were determined.Moreover the expression levels of salivary gland secretion related molecules,including MR1,MR3,APQ5,β1-AR,β2-AR,α-amylase,and mucin 5B gene were detected.Results There was no significant difference in the proliferation of DPSCs in the 6th and 8th generation deciduous teeth,and in the 6th and 8th generation permanent teeth(P>0.05),all reaching a plateau on the 9th day.There was no significant difference in the expression levels of DPSCs markers,including CD44,CD29,CD90,CD73,CD146,and CD105 of the 6th and 8th generation deciduous teeth,and the 6th and 8th generation permanent teeth(P>0.05).The expression level of MR1 was the highest in DPSCs of the 6th generation permanent tooth,followed by the 6th generation deciduous teeth,and the expression level of the 8th generation deciduous teeth was similar to that of the 8th generation permanent teeth.There was no significant difference in the expression level of MR3 in each group(P>0.05).The expression level of AQP5 in the 6th and the 8th generation deciduous teeth and in 6th generation permanent teeth was similar,which was significantly higher than that of 8th generation permanent teeth(P<0.05).The expression level ofβ1 AR was the highest in the 6th generation permanent teeth,which was significantly higher than that of other groups(P<0.05).The expression level ofβ2 AR was the highest in the 6th generation deciduous teeth,followed by the 6th generation permanent teeth,and the expression level of the 8th generation of deciduous teeth was the lowest,which was significantly lower than other groups(P<0.05).The expression level ofαamylase was the highest in the 6th generation permanent teeth,followed by the 8th generation permanent teeth.This level was significantly higher than that of the 6th generation deciduous teeth and the 8th generation permanent teeth,and the difference was statistically significant(P<0.05).Mucin 5B had the highest expression level in the 6th generation permanent teeth,followed by the 6th generation deciduous teeth,the 8th generation deciduous teeth,which had the lowest expressionlevels.The differences between groups were statisticallysignificant(P<0.05).Conclusion There are nosignificant differences in the growth of DPSCs andstem cell markers between permanent teeth anddeciduous teeth.The 6th and 8th generation deciduous teeth and permanent teeth express different levels of salivary gland secretion-related molecular genes.