重组人乳铁蛋白对缺铁性贫血大鼠铁营养状况的改善作用

Effects of recombinant human lactoferrin on improving the iron status of IDA rats

目的研究从转基因牛乳中分离纯化的重组人乳铁蛋白（rhLf）对缺铁性贫血（IDA）大鼠铁营养状况是否具有改善作用。方法雌性断乳Wistar大鼠喂饲低铁饲料建立IDA模型,按造模结束时Hb和体重随机分为6组,即模型对照组（A组）,0.375、0.75和2.25g/kg BW rhLf组（B、C、D组）,0.011g/kg BW乳酸亚铁组（E组）,0.375g/kg BW rhLf与0.011g/kg BW乳酸亚铁联合补充组（F组）,每组12只,每天一次性灌胃给予受试物,连续8周。检测指标包括动物一般情况、体重变化、Hb和RBC、游离原卟啉（FEP）、血清铁（SI）、总铁结合力（TIBC）、运铁蛋白饱和度（TS）、血清铁蛋白（SF）、血清Cu和血清Zn。结果与A组相比,E、F组大鼠一般情况明显改善,体重、RBC、Hb、SI、TS和SF显著增加,FEP、TIBC和血清Zn降低,机体铁营养状态基本恢复正常;D组上述指标较A组同样有显著性差异,但改善程度低于E、F组,动物仍处于缺铁状态;C组RBC较A组显著增加,FEP和血清Zn显著降低,其他指标无差异;B组仅血清Zn显著低于A组,其他指标无差异。E、F两组比较时,F组SI、TS和SF均显著高于E组,TIBC低于E组。结论单纯补充rhLf对IDA大鼠铁营养状况具有一定程度的改善作用,但较乳酸亚铁弱;乳酸亚铁与rhLf联合应用时改善机体铁营养状况的作用强于单纯补充乳酸亚铁或rhLf,同时可减轻亚铁离子导致的不良反应。

Objective To investigate the effect of recombinant human lactoferrin（rhLf）separated and purified from milk of transgenic cows on improving the iron status of rats suffered from iron deficiency anemia（IDA）.Method The IDA model of female weaning Wistar rats was induced by iron deficient diet,and the rats were then randomly divided into 6 groups（12 rats in each group,based on their body weight and the concentration of hemoglobin）： group A（the model control）,group B,C and D（rhLf 0.375.0.75 or 2.25g/kg BW）,group E（ferrous lactate 0.011g/kg BW）,and group F（ferrous lactate 0.011g/kg BW＋ rhLf 0.375g/kg BW）.Test substances were administered by gavage daily for 8 weeks.Related indexes,including general health condition,body weight,hematological parameters,free erythrocyte protoporphyrin（FEP）,serum iron（SI）,total iron binding capacity（TIBC）,serum ferritin（SF）,serum Cu and serum Zn,were determined.Results After 8 weeks of supplementation,body weight,RBC,Hb,SI,TS and SF levels of rats in group E and F were improved and significantly higher than those in group A,while levels of FEP,TIBC and Zn were lower.Indexes of rats in group D were also significantly different from those in group A but with a less degree than those in group E or F.Compared with group A,there were no obvious difference in iron status for group B or C except for more RBC and lower levels of FEP and Zn in group C,as well as the lower level of Zn in group B.SI,TS and SF levels in group F were significantly higher but TIBC was lower than those in group E.Conclusion The iron status of IDA rats could be improved to some degree by the supplementation of rhLf alone,but the effect was weaker than that of ferrous lactate.The effect of combining rhLf with ferrous lactate was more intensive than ferrous lactate or rhLf administered individually.