17β-雌二醇对骨外膜来源成骨样细胞增殖及基因表达的影响

Effect of 17β-estradiol on the proliferation and genes expression of periosteum-derived osteogenic cells

目的探讨17β-雌二醇（17β-E2）对骨外膜来源成骨样细胞增殖及基因表达的影响。方法6周龄雌性Wistar大鼠颅骨骨外膜来源的成骨样细胞分别在含有0．01、0．05、0．1、0．25、0．5、0．75、1、5、10nmol／L9种浓度17β-E2的成骨诱导培养液中培养，用MTF法测定3、6、9、12d时细胞的增殖情况。用RT—PCR法测定7d时细胞Ⅰ型胶原蛋白仅。链（COLLI）、骨桥接素（OPN）、骨保护素（OPG）及RANKL基因的表达。结果17β-E2作用6、9d时，雌激素组的增殖水平显著高于对照组（P〈0．05）；12d时，0．05nmol／L及以上组的增殖水平显著高于对照组（P〈0．05），各雌激素组的增殖水平的差异无统计学意义（P〉0．05）。（1）COLLI：对照组的表达水平显著高于雌激素组（氏0．05）；在雌激素组中0．5nmo／／L组的表达水平最高，0．75nmol／L组次之，二者皆显著高于其他各组（P〈0．05）。（2）OPN：0．1nmol／L及以上组的表达水平显著高于对照组（P〈0．05）。（3）OPG和RANKL：OPG表达阴性，RANKL在对照组及雌激素组中均有较高水平的表达。结论雌激素对骨外膜成骨样细胞的调节可能以促进增殖，抑制分化为主。骨外膜来源成骨样细胞对破骨细胞的调节可能以促进其祖细胞分化为主。

Objective To explore the effects of 17β-estradiol on the proliferation and the mRNA expression level of different genes of periosteum-derived osteogenic cells, an experimental study was conducted. Methods MTT assay was used to determine the proliferation state of 6-week-old female rat calvaria periosteum-derived osteogenic cells at the 3th, 6th, 9th and 12th day under the treatment of 0.01, 0.05, 0.1, 0.25, 0.5, 0.75, 1, 5, 10 nmol/L 17β-estradiol. RT-PCR assay was used to determine the mRNA expression level of different genes of the cells at the 7th day. Results 1. Cell proliferation state： after treated for 6, 9 days, all 17β-estradiol treatment groups have significantly higher level than the control group. For 12 days, 0.05 nmol/L and above 17β-estradiol treatment groups have significantly higher level than the control group （P〈 0.05）. 2. Gene expression level： （1） Type Ⅰ collagen α1 chain（COLLI） expression level of control is significantly higher than estrogen treatment groups. 0.5 nmol/L group has the highest expression level, followed by 0.75 nmol/L group. Both of them have significantly higher expression than other estrogen treatment groups. （2） The osteopontin （OPN） expression level of 0.1 nmol/L and above groups is significantly higher than the control group. （3） Both estrogen treatment and control group have high expression of RANKL, while osteoprotegerin （OPG） expression is negative. Conclusion The effects of estrogen on periosteum-derived osteogenic cells are mainly to stimulate proliferation and inhibit differentiation. The regulation of periosteum-derived osteogenic cells on osteoclasts is to stimulate the differentiation of their progenitors.