雌激素减少对大鼠铁代谢的影响

Effect of estrogen deficiency on iron metabolism in rats

目的在机体,铁调素(Hepcidin)、膜转铁蛋白(FPN)、二价金属转运蛋白1(DMT1)、十二指肠色素b(DCYTB)是调节铁代谢的重要通道蛋白;本研究通过观察大鼠去势后铁代谢相关通道蛋白基因表达的变化,探讨雌激素与铁代谢的关系。方法雌性大鼠12只,随机分为2组:一组大鼠切除双侧卵巢(去势组),一组切除卵巢周脂肪(对照组),12 w后取标本检测观察;观察指标:①酶联免疫吸附法(Elisa)检测雌二醇浓度,②全自动生化分析仪检测大鼠血清铁,③电感耦合等离子体发射光谱仪原子吸收法检测鼠胫骨铁含量、肝组织铁含量,④半定量RT-PCR法检测肝脏Hepcidin、FPN的表达,以及十二指肠FPN、DMT1、DCYTB的mRNA的表达。结果去势组3项指标(雌二醇19.45±2.28 ng/L、血清铁36.36±9.34μmol/L、胫骨铁含量41.00±5.59μg/g)比对照组相应指标(雌二醇34.98±4.48 ng/L、血清铁54.73±11.08μmol/L、胫骨铁含量66.92±21.94μg/g)显著降低(P<0.05);去势组肝脏铁含量(750.20±94.08μg/g)比对照组(369.60±61.87μg/g)显著升高(P<0.05);RT-PCR结果显示:两组均有肝脏Hepcidin和FPN mRNA表达,表达水平两组比较存在显著差异;两组均有十二指肠FPN、DMT1和DCYTB mRNA表达,其中FPN、DCYTB mRNA表达水平两组比较有显著性差异,DMT1两组比较无明显变化。结论大鼠去势后可以使调控铁代谢的基因通道发生改变,影响铁的摄入和分布。

Objective Hepcidin, FPN, DMT1, and DCYTB are iron-regulating channel proteins in the body. This study was to explore the relationship between estrogen and iron metabolism by observing the changes of the gene expression of iron metabolism related channel protein in ovariectomized rats. Methods Twelve female SD rats were randomly divided into 2 groups： OVX group and Sham group. Rats in OVX group underwent bilateral ovariectomy, while rats in Sham group were excised some fat tissue around the ovaries. Twelve weeks later, the specimen were collected. The serum concentration of E2 was detected using ELISA method. The serum iron was detected using were automatic biochemical analyzer. The iron content in the liver and the tibia was detected using an ICP tester. The expression of hepcidin and ferropotin （FPN） mRNA in the liver and the expression of FPN, DMT-1, and DCYTB mRNA in the duodenum were detected using semi-quantitative reverse transcription-polymerase chain reaction （RT-PCR）. Results The serum levels of E2 and iron, as well as the iron content in the tibia in OVX group were 19.45 ± 2.28ng/L, 36.36 ± 9.34 μmol/L, and 41.00 ± 5.59 μg/g, respectively, which were significantly lower than those in Sham group （34. 98 ± 4.48 ng/ L, 54.73 ± 11.08 μmol/L, and 66.92 ±21.94 μg/g, respectively, P 〈 0. 05 ）. On the contrary, the iron content in the liver in OVX group was significantly higher than that in Sham group （750.20 ± 94.08 μg/g VS 369.60 ± 61.87 μg/g, P 〈 0.05 ）. The results of RT-PCR revealed that the expression of hepcidin and FPN mRNA in liver in both groups was observed, showingsignificant different between 2 groups. The expression of FPN, DMT-1, and DCYTB mRNA in the duodenum in both groups was observed, and the expression of FPN and DCYTB mRNA showed significant difference between 2 groups, while no significant change of the expression of DMT1 mRNA was observed. Conclusion The ovariectomy in rats may change the channel proteins modulating the iron metabolism, thus affecting the absorption and distribution of iron.