机械压应力刺激对人牙髓干细胞体外增殖矿化的影响

摘要

目的：研究不同大小的周期性机械压应力刺激对人牙髓干细胞（hDPSCs）体外增殖和矿化的影响。方法：用体外离心力加压模式，对各组hDPSCs施加30 min／d、大小分别为170、210、250 g的周期性机械压应力刺激，以不加力组作为对照。分别利用CCK－8试剂盒及碱性磷酸酶（ALP）试剂盒检测各组hDPSCs的增殖情况及ALP活性；茜素红染色检测各组hDPSCs的矿化能力；透射电镜观察各组hDPSCs的超微结构。结果：3种大小的机械压应力刺激均可显著抑制hDPSCs增殖、ALP活性显著下降（P＜0．05）；各加力组形成的矿化结节明显减少，且以250 g的应力刺激对矿化能力的抑制最为显著（P＜0．05）。结论：一定大小、频率范围内的周期性机械压应力刺激可抑制人牙髓干细胞体外增殖和矿化，且对矿化的抑制作用与周期性机械压应力大小成正相关。%AIM:To explore the effects of mechanical stress on the proliferation and differentiation of human dental pulp stem cells(hDPSCs).METHODS:Human DPSCs were cultured and subjected to cyclic mechanical stress at 170 g,210 g and 250 g respectively for 30 min every day.Untreated DPSCs served as controls.After that,cell pro-liferation and ALP activity was examined by CCK-8 and ALP kit respectively.The formation of mineralized nodules was determined using half-quantitative Alizarin Red S assay.Cell ultrastructure was observed by the transmission electron microscope.RESULTS:CCK-8 results demonstrated that cell proliferation was reduced(P<0.05),ALP activity and mineralization capacity of stress-treated DPSCs were descended by the stress treatment.The 250 g group had the most significant inhibition(P<0.05).CONCLUSION:Cyclic mechanical stress can inhibit the proliferation and minerali-zation of hDPSCs in vitro in a stress value dependent manner.