雌激素对成骨细胞增殖及IGF-2表达的调控作用

目的 探讨雌激素对大鼠成骨细胞功能的影响及胰岛素样生长因子2（insulin-like growth factor 2，IGF-2）表达的调控机理。方法应用1×10^-10mol／L、1×10^-8mol／L、1×10^-6mol／L浓度的雌二醇（estradiol，172）分别作用原代培养的新生大鼠颅盖骨成骨细胞24h；采用MTT法和对硝基酚磷酸盐法检测成骨细胞增殖能力和细胞中碱性磷酸酶（ALP）活性；应用实时定量PCR和Western印迹杂交分析成骨细胞中IGF-2的mRNA和蛋白质的表达规律。结果1×10^-6mol／L浓度的磁使大鼠成骨细胞增殖能力和ALP活性分别增加了67％和55％，使IGF-2的mRNA与蛋白质的表达水平分别增加了90％和140％，差异有统计学意义（P〈0．05）。结论雌激素对成骨细胞中IGF-2基因的表达具有正性调控作用。成骨细胞中IGF-2的高表达可能与雌激素调节成骨细胞增殖和分泌功能相关。

EFFECTS OF ESTROGEN ON PROLIFERATION AND IGF-2 EXPRESSION OF RAT OSTEOBLASTS

Objective To investigate the effects of estrogen on the gene expression of insulin-like growth factor 2 （IGF-2） and the cell function in rat osteoblasts. Methods The osteoblasts from newborn rat cranium were cultured in the presence of estradiol （1 × 10^-10 mol/L, 1× 10^-8 mol/L, 1×10^-6mol/L） for 24 hours. Nitrophenol phosphate salt method and MTT assay were used to measure the alkaline phosphatase （ALP） and the cell proliferation of osteoblasts. IGF-2 mRNA and protein levels in rat osteoblasts were detected by real time polymerase chain reaction and Western blotting. Results The cell proliferation and the ALP activity in estradiol-treated （1×10^-6 mol/L） osteoblasts were increased 67% and 55%, respectively, compared with those of the control group （P〈0.05） ; IGF-2 mRNA and protein were increased 90% and 140% respectively （P〈0. 05）, when treated with estradiol （1 × 10^-6 mol/L） . Conclusion The IGF-2 gene expression in rat osteoblasts was up-regulated with estrogen. This regulation may be related with the hormonal modulation of cell proliferation and secretion in osteoblasts.