Mechanical Tensile Stress Effects on the Expression of Bone Sialoprotein in Bovine Cementoblasts
Mechanical Tensile Stress Effects on the Expression of Bone Sialoprotein in Bovine Cementoblasts
复制标题
机械拉应力对牛成牙骨质细胞骨唾液酸蛋白表达的影响
DOI：
10.2319/011508-20.1
复制
发表时间：
2009-03-01
影响因子：
3.4
通讯作者：
Bai, Ding
中科院分区：
文献类型：
--
作者：
Yu, Hongyou;Ren, Yijin;Bai, Ding
目的：为建立一种新的成牙骨质细胞培养方法，并检测成牙骨质细胞在高、低机械张应力作用下骨唾液蛋白（BSP）的表达。材料与方法：取新生牛牙根成牙骨质细胞，用牙骨质附着蛋白（CAP）抗体3G 9鉴定。通过MTT [3-（4，5-dimethylthazol-2-yl）-2，5-diphenyl tetrazolium bromide]测定评价细胞增殖，并通过von Kossa染色证实矿化。机械拉伸应力施加在体外的cementoblast与使用单轴四点弯曲系统与2000或4000微应变，在0.5 Hz的频率为3，6，12，24，或36小时。实时定量逆转录聚合酶链反应（qRT-PCR）检测BSP mRNA水平。结果：成牙骨质细胞大量表达CAP。成牙骨质细胞的增殖趋势与成骨细胞相似，但与牙周膜细胞不同。成牙骨质细胞具有介于成骨细胞和PDL细胞之间的矿化能力。2000和4000微应变组BSP mRNA表达均在24 h时达到峰值（P <0.01），分别为对照组的10倍和6倍。两组BSP表达均在36 h时下降至基线水平。结论：机械张应力上调BSP表达。低机械拉伸应力诱导BSP mRNA的早期和更强烈的上调，这可能是最佳的刺激成牙骨质细胞的活动。（角度正交2009;79：346-352）。
Objective: To develop a new cementoblast culture method and to detect bone sialoprotein (BSP) expression in response to high and low mechanical tensile stress in cementoblast in vitro.Materials and Methods: Cementoblasts were collected from the roots of newborn bovine teeth and were identified with cementum-derived attachment protein (CAP) antibody 3G9. Cell proliferation was evaluated by MTT [3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay, and mineralization was confirmed by von Kossa staining. Mechanical tensile stress was applied in vitro to the cementoblast with the use of a uniaxial four-point bending system with 2000 or 4000 microstrains, at a frequency of 0.5 Hz for 3, 6, 12, 24, or 36 hours. BSP mRNA level was quantified by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR).Results: A large amount of cementoblast was observed to be expressing CAP. Cementoblasts had a proliferation tendency similar to that of osteoblasts but different from that of periodontal ligament (PDL) cells. Cementoblasts had the ability to become mineralized between osteoblasts and PDL cells. The mechanical tensile stress significantly up-regulated BSP mRNA expression, which reached a peak at 24 hours in both 2000 and 4000 microstrain groups (P < .01) and was tenfold and sixfold higher than that of controls, respectively. BSP expression dropped toward baseline levels at 36 hours in both groups.Conclusions: Mechanical tensile stress up-regulated the expression of BSP. Low mechanical tensile stress induced earlier and more intensive up-regulation of BSP mRNA; this might represent the optimal stimuli for cementoblast activity. (Angle Orthod. 2009;79:346-352.)