The Impact Of Dietary Iron Contents And Aerobic Exercise On Hematological And Hippocampal Iron Status In Female Rats

ObjectivesThis study aimed to observe the effects of dietary iron contents on thehematological iron status and the hippocampal non-heme iron (NHI) contents underthe long-term exercise condition in the female rats.MethodsThe animals were used for two experiments. In the first experiment, the sixtyweaning female rats were divided into three groups, a dietary iron deficiency group(12mg/kg, SS2), a dietary iron sufficiency group (45mg/kg, SS2) and a high dietaryiron content group (1000mg/kg, SH2); and the animals were fed with theircorresponding iron diet for one month. In the second experiment, one hundred andeight weaning female rats were assigned into three groups, a dietary iron deficiencygroup (12mg/kg), a dietary iron sufficiency group (45mg/kg) and a high dietary ironcontent group (1000mg/kg). Those animals were fed with their corresponding irondiet for one month. After one month, the second experiment was further divided intoan exercise group and a sedentary group: exercise group with dietary iron deficiency(EL), sedentary group with dietary iron deficiency (SL), exercise group with dietaryiron sufficiency (ES), sedentary group with dietary iron sufficiency (SS), exercisegroup with high dietary iron content (EH) and sedentary group with high dietary iron content (SH). The rats in the three exercise groups were exposed to swimming forthree months(5d/week, one exercise session/d). All the corresponding sedentarygroups were treated approximately the same way as the exercised rats, except forswimming. At the end of the experiments, animals were fasted for24hours and thenblood collection was taken from their vein under pentobarbital anesthesia foranalyzing blood hemoglobin (Hb), hematocrit (HCT), mean corpuscular volume(MCV), mean corpuscular hemoglobin (MCH), red cell distribution (RDW), serumiron (SI) and total iron binding capacity (TIBC). The hippocampi were removed andquick-freezing in liquid nitrogen, and then stored at-80°C refrigerator for thedetermination of the NHI in the hippocampus.Results1. The impact of dietary iron contents and long-term exercise on peripheral ironstatus in female ratsDietary iron contents affected Hb, HCT, MCV, MCH, RDW, TIBC, TS (P<0.01)and SI (P<0.05), and that exercise affected Hb, HCT, MCH, SI and TS (P<0.05).Compared to SS group, TS (P<0.05), MCV and MCH (P<0.01) weresignificantly decreased, TIBC and RDW were significantly increased (P<0.01) in SLgroup. In SH group, Hb was decreased (P<0.05), and HCT was increased (P<0.05),but MCH, RDW, SI, TIBC and TS had no significant difference (P>0.05).Compared to ES group, MCV, MCH, SI and TS were significantly decreased(P<0.01), TIBC and RDW were significantly increased (P<0.01) in EL group. In EHgroup, Hb was increased (P<0.05), but HCT, MCV, MCH, RDW, SI, TIBC and TShad no significant difference (P>0.05).Compared to SL group, SI and TS were significantly decreased (P<0.01), Hb,HCT, MCH, MCV were increased (P<0.05), but RDW and SI had no significantdifference (P>0.05) in EL group.Compared to SS group, Hb, HCT, MCV, MCH were increased (P<0.05), SI,TIBC, TS and RDW had no significant difference (P>0.05) in ES group.Compared to SH group, Hb, HCT, MCV, MCH, RDW, SI, TIBC and TS had nosignificant difference (P>0.05) in EH group. 2. The impact of dietary iron contents and long-term exercise on hippocampal ironstatus in female ratsDietary iron contents affected NHI in the hippocampus (P<0.01), and exercisedid not affect NHI in the hippocampus (P<0.05).Compared to ES group, NHI was significantly decreased (P<0.01) in EL groupand had not significant difference (P>0.05) in EH group. Compared to SS group, NHIwas significantly decreased (P<0.01) in EL group and had not significant difference(P>0.05) in EH group. Compared to the sedentary group, it had not significantdifference (P>0.05) in EL, ES and EH group.Compared to the sedentary group in the first experiment, NHI was increased(P<0.05) in EH group and had no difference (P>0.05) in EL and ES group. NHI wassignificantly was increased (P<0.01) in SH group and had not significant difference(P>0.05) in SL and SS group.Conclusion1. Long-term dietary iron deficiency could lead nutritional iron deficiency in rats.2. In the case of low dietary iron content, long-term exercise could further decreaseserum iron status. In the case of sufficient dietary iron content, long-term exercisemay increase Hb and HCT, but SI has no difference. In the case of high dietaryiron content, long-term exercise do not significantly change hematological ironstatus.3. The impact of exercise and diet iron content of the interaction between the femalerats, Dietary iron contents affected NHI, hippocampal NHI was decreased in lowiron content diet group. In the case of low dietary iron content, long-term exercisecould further decrease NHI; In the case of sufficient and high dietary iron,long-term exercise not significantly change NHI.4. In the case of low and high dietary iron, hippocampus NHI were significantlydecreased before exercise. The low iron content diet group were decreased andthe case of high dietary iron returned to normal levels after exercise, it suggestingthat hippocampus NHI of female rats was not affected by exercise, thehippocampus has a mechanism to maintain iron metabolism.