摘要
背景：人胰岛索样生长因子I在成骨细胞中含量丰富，与骨密度有密切关系。目的：观察重组人胰岛素样生长因子I对体外培养大鼠成骨细胞的增殖、凋亡及碱性磷酸酶合成的影响。方法：不同质量浓度重组人胰岛素样生长因子I刺激体外培养的大鼠成骨细胞，噻唑蓝法测定活细胞数量；肿瘤坏死因子a单独或与重组人胰岛素样生长因子I共同刺激成骨细胞，流式细胞仪检测细胞周期和凋亡率，采用对硝基酚磷酸盐法测定细胞裂解液中碱性磷酸酶活性。结果与结论：与对照组相比，一定剂量的重组人胰岛素样生长因子I能明显增加大鼠成骨细胞数量（P〈0．05），在质量浓度为0．1-100pg／L时，成骨细胞数量的增加与质量浓度呈正相关；肿瘤坏死因子a在0．1-100pg／L范围内呈剂量依赖性地促进成骨细胞凋亡（户〈0．05），并使S期细胞减少（尸〈0．05），而重组人胰岛素样生长因子I能抑制肿瘤坏死因子a对成骨细胞的促凋亡作用（P〈0．05）：与对照组相比，重组人胰岛素样生长因子I刺激的成骨细胞碱性磷酸酶的活性明显增高（尸〈0．05）。重组人胰岛素样生长因子I对大鼠成骨细胞有明显的促增殖作用，且能明显抑制肿瘤坏死因子a诱导的大鼠成骨细胞凋亡，提示增加成骨细胞数量可能是重组人胰岛索样生长因子I促进骨形成的机制之一：重组人胰岛素样生长因子I能促进大鼠成骨细胞碱性磷酸酶的合成，提示重组人胰岛素样生长因子I有可能促进骨基质的合成和钙化。
BACKGROUND： Recombinant human insulin-like growth factor （rhlGF- I ） is rich in osteoblasts, which has close contact with bone mineral density. OBJECTIVE： To investigate the effects of rhlGF- I on proliferation, apoptosis and synthesis of alkaline phosphatase （ALP） of rat osteoblasts in vitro. METHODS： Rat calvaria cells were cultured in medium with or without rhlGF- I. The living cell number was assessed by MTT colorimetric assay. Tumor necrosis factor a （TNF-a） was added in the medium to induce apoptosis. The cell cycle and apoptosis were analyzed by flow cytometry after the cells were incubated with medium containing TNF-a or TNF-a plus rhlGF- I. The ALP content within osteoblasts was measured by PNPP method. RESULTS AND CONCLUSION： The cell number of osteoblasts exposed to rhlGF- I at 102-105 ng/mL significantly increased compared with control group （P 〈 0.05）. TNF~ （102 105 ng/L） caused a dose-dependent increase of apoptosis （P 〈 0.05） and decreased the cell number in S phase （P 〈 0.05）. rhlGF- I inhibited the inducement of TNF-a for apoptosis. The ALP activity in rhlGF- I -treated cells was higher than that in vehicle-treated cells （P 〈 0.05）. IGF- I can stimulate proliferation of osteoblasts and inhibit apoptosis induced by TNF-a in vitro, these results suggested that increasing the cell number of osteoblasts might be one of the mechanisms for IGF- I to promote bone formation. IGF- I can increase ALP synthesis in osteoblasts in vitro, this result suggested that IGF- I could probably promote the synthesis of organic matrix and mineralize action of bone.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2011年第11期1901-1904,共4页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
江苏省自然科学基金(BK2009208),C 反应蛋白调控脂联素表达的分子机制研究~~
