中文摘要：

目的探讨低氧对人牙周膜干细胞（PDLSCs）骨向分化的影响。方法采用组织块法体外分离培养PDLSCs,分别在常氧和低氧条件下培养PDLSCs,低氧组在2%O2浓度下培养6、12、24、48 h后检测其碱性磷酸酶（ALP）活性,并通过荧光定量PCR检测低氧培养的PDLSCs中骨钙素（OCN）、低氧诱导因子1α（Hif-1α）、碱性磷酸酶（ALP）以及成骨相关基因核心结合因子（Runx-2）等基因的表达变化;通过Western blot法检测低氧培养的PDLSCs中Runx-2、Hif-1α等蛋白的表达变化。结果低氧组的PDLSCs的ALP水平高于常氧组,但低氧48h开始抑制ALP水平,荧光定量PCR和Western blot结果显示低氧培养48h内的PDLSCs的成骨能力高于常氧组,但低氧培养48h则抑制其成骨能力。结论48h内低氧可显著增强PDLSCs骨向分化作用,48h则开始抑制其成骨能力。

英文摘要：

Objective To investigate the effects of the hypoxia on the osteogenic differentiation of the human periodontal ligament stem cells（ PDLSCs）. Methods The PDLSCs were cultured under hypoxia and normal condition.Cells in the hypoxia group were incubated in 2% O2 for 6,12,24,48 h,and then ALP activity analysis was used to analyze the relative ALP activity. The expressions of OCN,Hif-1α,ALP,Runx-2 mRNA were detected by QPCR,while Western blot was used to analyze the expressions of Runx-2,Hif-1α protein. Results The osteogenic differentiation of PDLSCs under hypoxia condition was higher than the osteogenic differentiation of PDLSCs cultured under nomoxia condition,however,the osteogenic differentiation of PDLSCs cultured under hypoxia condition for 48 h was inhibited. Conclusion Hypoxia can enhance the osteogenic differentiation of PDLSCs within 48 h,however,inhibit the osteogenic differentiation of PDLSCs after 48 h.