低氧训练对大鼠骨骼肌HIF-1 mRNA及铁转运蛋白表达的影响

Effects of Hypoxic Training on the Expression of HIF-1 mRNA and Iron Metabolism Proteins of Skeletal Muscle in Rats

目的：探讨低氧、低氧训练对大鼠骨骼肌铁代谢的影响。方法：32只雄性SD大鼠随机均分为常氧安静组（NC）、常氧运动组（NE）、低氧安静组（HC）和低氧运动组（HE）。跑台训练（21～25m／min，每周增1m／min，1h／天，6天／周），HC组进行低氧暴露（13．6％氧，8h／天，6天／周）。原子吸收法、RT—PCR、Westernblot检测结果。结果：与NC组比，各组大鼠腓肠肌总铁含量升高（P〈0．05，P〈0．01）；HE组高于NE、HC组（P〈0．05）。HC和HE组骨骼肌HIF-1 mRNA表达高于NC、NE组（P〈0．01）。与NC组相比，NE、HC、HE组骨骼肌铁吸收蛋白升高（P〈0．05，P〈0．01）；NE、HC组铁释放蛋白下降（P〈0．05，P〈0．01），HE组升高（P〈0．01）；HE组各蛋白表达均高于NE和HC组（P〈0．01）。结论：大鼠适度运动和单纯低氧均能增加骨骼肌铁贮存，而低氧训练能促进骨骼肌铁吸收和铁释放。

Objective：To investigate the effect of hypoxic training on iron metabolism in muscle of rats. Methods：Thirty-two male SD rats were randomly divided into four groups：the normal control group （NC）, the normal exercise group （NE）, the hypoxia control group （ HC）, and the hypoxia exercise group （HE）. The rats were respectively run （21-25m/min, 1h/d） or exposure to hypoxia （13.6%,8h/d） and then were sampled after 5 weeks. Western blot, RT- PCR, atomic absorption spectro-photometer were used . Results： 1） Compared with NC, the iron content of skeletal muscle of NE, HC and HE groups were significantly increased, and HE group was much higher than NE and HC groups（P〈0. 01）. 2） The HIF-1 mRNA of HC and HE groups were much higher than the NC and NE groups （P〈0.01）. 3） Compared with NC, the expression of DMT1, TfR1 in NE, HC, HE were significantly increased （P〈0.05, P〈0.01） . The expression of FPN1 in NE and HC were significantly lower than that of NC （P〈0.05, P〈0.01）, while the expression of FPN1 in HE group was significantly increased （P〈0.01） than the other three groups. The expression of DMT1,TfR1 and FPN1 in HE were higher than the NE and HC groups （P〈0.01）. Conclusions：The iron storage of skeletal muscle was increased after the moderate exercise and exposure to hypoxia, while the hypoxia training was much more useful to improve the iron content of skeletal muscle.