Effects Of Hypoxia On The Osteogenic Differentiation Of PDLSCs

Objective In the experiments,the method of tissue block was used to culture human periodontal ligament stem cells(HPDLSCs),HPDLSCs were cultured in the hypoxia condition and normal condition,and investigate the effects of the hypoxia on the osteogenic differentiation of HPDLSCs.Methods First, the method of tissue block was used to culture the HPDLSCs, and observed the morphology of the HPDLSCs.Second, the HPDLSCs were cultured under hypoxia and normal condition,the hypoxia condition contained 2% O2、5% CO2 and 93% N2, the normal condition contained 20% O2、5% CO2 and 75% N2.Cells in the hypoxia group and normal group were cultured for 6,12,24,48 h,then MTT and ALP activity analysis were used to analyze the proliferation and the relative ALP activity of the HPDLSCs.The expressions of OCN,Hif-1α,ALP,Runx2 m RNA were detected by QPCR,while Westernblot was used to analyze the expression of Runx2,Hif-1α protein.Results The HPDLSCs adhered to the wall on 7-15 d,the obtained putative stem cells exhibited a typical fibroblast-like spindle appearence.Compared with the nomoxia group,the proliferation of the HPDLSCs cultured under hypoxia were higher.The relative ALP activity of HPDLSCs under hypoxia condition were higher than that of HPDLSCs cultured under nomoxia condition, however,the relative ALP activity of HPDLSCs cultured under hypoxia condition for 48 h were inhibited.QPCR and Westernblot showed that the osteogenic differentiation of HPDLSCs under hypoxiaondition were higher than the that of HPDLSCs cultured under nomoxia condition, however,the osteogenic differentiation of HPDLSCs cultured under hypoxia condition for 48 h were inhibited.Conclusion Hypoxiacan enhance the osteogenic differentiation of HPDLSCs within 48 h,however inhibites the osteogenic differentiation of HPDLSCs after 48 h.