低氧对人牙周膜细胞骨向分化能力的影响

目的 研究低氧对人牙周膜细胞（PDLC）的碱性磷酸酶（ALP）活性及成骨相关基因表达的影响.方法 采用组织块法体外分离培养人PDLC;取第3 ～ 5 代细胞分别在常氧和低氧条件下培养后检测其ALP 活性;并通过荧光定量聚合酶链反应（PCR）观察低氧处理后人PDLC 中成骨相关基因的表达变化.结果 低氧12、24、36、48 h 组ALP 活性均比常氧组高;其中低氧48 h 组与常氧组相比明显升高,差异有统计学意义（P ＜ 0.05）;低氧48 h 组ALP mRNA 表达比常氧组高,差异具有统计学意义（P ＜ 0.05）;4 个时间点低氧组骨钙蛋白（OCN）mRNA 表达均比常氧组高,且差异有统计学意义（12、36 h：P ＜ 0.05;24、48 h：P ＜ 0.01）.结论 低氧增强人PDLC 的ALP 活性,上调ALP mRNA 和OCN mRNA 的表达,促进人PDLC 向成骨细胞分化,同时促进成骨细胞的矿化,提示低氧环境对人PDLC 的骨向分化功能产生一定的影响.

Effects of hypoxia on the osteogenic differentiation of human periodontal ligament cells in vitro

Objective To investigate the biological effect of hypoxia on the alkaline phosphatase activity and expression of alkaline phosphatase （ALP） ＆ osteocalcin （OCN） mRNA of human periodontal ligament cells （PDLCs）. Methods Human periodontal ligament ceils were cultured in hypoxia and normal condition. In the hypoxia group, ceils were incubated in 1.5%-2% 02 for 12,24,36,48 h. ALP activity was analyzed,and expression of ALP and OCN mRNA was detected by quantitative PCR. Results In the 48 h group, ALP activity in the hypoxia group was significantly higher than that in the control group （P 〈 0.05）. ALP mRNA expression level was significantly higher in the hypoxia group than control group in 48 h （P 〈 0.05）, whereas the expression levels of OCN mRNA were significantly higher in the hypoxia groups than in control groups in all 4 time groups （12 h, 36 h：P 〈 0.05;24 h, 48 h： P 〈 0.01）. Conclusions Hypoxia can enhance the ALP activity of human PDLCs, and promotes the expression of ALP mRNA and OCN mRNA, which suggests that hypoxia may be able to improve the osteogenic activity of human PDLCs at early stage.