不同强度游泳运动对大鼠贮存铁及十二指肠铁吸收相关蛋白表达的影响

Effects of Swimming with Different Intensities on the Iron Storage and the Expression of Duodenal Iron Absorption Proteins in Rats

目的:观察不同强度游泳训练后大鼠机体贮存铁及十二指肠铁吸收相关蛋白的变化,探讨不同强度运动对机体内铁贮存及铁吸收的影响机制。方法:60只雌性SD大鼠随机分为对照组(controlgroup,CG),适度运动组(moderatelyexercisedgroup,MG)和过度运动组(strenuouslyexercisedgroup,SG),每组20只,分别于运动5周和10周后取材。采用酶联免疫吸附法(ELISA)检测血清铁蛋白(serumferritin,SF)含量;测定肝脏和骨髓非血红素铁含量;采用WesternBlot法检测十二指肠上皮细胞二价金属离子转运体1(divalentmetaltransporter1,DMT1)和膜铁转运蛋白1(ferroportin1,FP1)的变化。结果:(1)运动10周后,MG组大鼠SF和Hb显著高于SG组和CG组(P<0.05),而SG组大鼠SF显著低于CG组(P<0.05);MG组和SG组大鼠骨髓非血红素铁含量均显著低于CG组(P<0.01)。(2)MG组十二指肠上皮细胞DMT1(IRE)和FP1表达均显著高于CG组(P<0.05),而SG组DMT1和FP1表达与CG组和MG组相比均无显著差异。结论:适度运动可增加十二指肠铁转运蛋白表达,促进肠铁吸收,使血清铁增多、贮存铁重新分布,满足运动中机体对铁的需求;而过度运动使贮存铁大量消耗,从而易引发非贫血性铁缺乏。

Objective To investigate the effects of swimming with different intensities on the iron storage and the regulatory mechanism of iron absorption, the expression of divalent metal transporter 1 （ DMT1 ） and ferroportinl （FP1） in rats＇ duodenal epithelium was observed. Methods Sixty female SD rats （90- 100g） were randomly and equally divided into three groups： control group （CG）, moderate exercise group （MG） and strenuous exercise group （SG）. The rats were sampled after 5 - and 10 - week swimming. Serum ferritin（SF） was measured using ELISA. The non - heme iron in bone marrow and liver was determined. The expression of DMT1 and FP1 was measured by Western Blot. Results （ 1 ） SF and Hb of MG were significantly increased than that in CG and SG （ P 〈 0.05）, and SF of SG was decreased after 10 - week swimming. Non - heme iron in bone marrow in MG and SG was lower than that in CG. （2） The expression of DMT1 （IRE） and FP1 was significantly increased in MG as compared with that in CG （ P 〈 0.05）. There was no significant change of DMT1 and FP1 level in SG. Conclusion Moderate exercise could the epithelium and in turn iron absorption was enhanced to the stored iron was depleted after strenuous exercise which increase the expression of iron - related proteins on meet iron requirement during exercise. In contrast, led to exercise - induced iron deficiency.