| The incidence of iron deficiency with or without anemia in the exercise population is higher than that in the general population.It is a common phenomenon for the exercise population to supplement excessive iron.In recent years,some progress concerning the influence of exercise on hippocampus iron metabolism has been made.However,there is few research on whether exercise affects iron metabolism in cerebral cortex and striatum when the diet is iron-deficient or iron-overloaded.The interaction between exercise and dietary iron contents on iron metabolism in the cerebral cortex and striatum has not been reported yet.In this study,iron-deficient diet,iron-adequate diet,iron-overloaded diet,and long-term aerobic exercise(swimming exercise)were used in rats,(1)to observe the effects of diet with different iron contents and exercise on the iron status,other metal ions(manganese,cooper,zinc,calcium)contents,and redox status of the cerebral cortex and striatum in the growth stage(from childhood to adulthood);(2)to analyze the interaction between dietary iron contents and exercise;and(3)to observe whether or how the molecular biology mechanism of iron metabolism is changed in cerebral cortex.The research results may be valuable for the scientific and reasonable diet,iron supplement and exercise for the adolescent population who are long-term dietary iron deficiency and iron overload.Ninety weaning female rats were randomly divided into three groups,respectively fed with iron-deficient diet(12 mg/kg),iron-adequate diet(45 mg/kg),and iron-overloaded diet(1000 mg/kg).O ne month later,each group was divided into an exercise group and a sedentary group,and thus there were six groups: three sedentary groups,respectively with iron-adequate diet(IADS,n=12),iron-deficient diet(IDDS,n=12),and iron-overloaded diet(IODS,n=12),and three groups,respectively with iron-adequate diet(IAD)plus exercise(IADE,n=18),iron-deficient diet(IDD)plus exercise(IDDE,n=18),iron-overloaded diet(IO D)plus exercise(IODE,n=18).Exercise rats were allowed to swim for five days per week,once a day.They were expected to experience an adaptation period for 2 weeks,swimming for 30 minutes in the first week,60 minutes in the second week,and then to maintain 120 minutes per day from the third week.The exercised rats swam for 3 months while the sedentary rats were kept sedentary in their cages.Animals were fasted for 24 hours after the last exercise regimen.The weight of body and organs including liver,spleen and heart of rats were measured.The cerebral cortex,striatum,medulla oblongata,and midbrain were isolated and their non-heme iron(NHI),manganese,copper,zinc,selenium and calcium contents were measured.The redox status of the cerebral cortex and striatum,and the iron metabolism related proteins of the cerebral cortex were determined.In addition,NHI contents in spleen were analyzed in order to observe the effects of dietary iron levels and exercise on the peripheral iron storage.The main results and conclusions are as follows:1.Compared to IADS,no differences were found in NHI contents of cerebral cortex in IDDS and IODS;manganese contents in cerebral cortex were significantly increased in IDDS,copper and calcium contents in cerebral cortex were significantly decreased in IODS.No significant difference s were found in NHI,manganese,copper,zinc,calcium,selenium contents in cerebral cortex of rats fed with IDD and IAD between exercise groups and sedentary groups.Compared to IO DS,exercise significantly increased selenium contents,and no differences were found in NHI,manganese,copper,zinc,calcium contents in cerebral cortex.There was a positive correlation of NHI with manganese,zinc,or calcium contents in IODE.The results show that in the case of iron-overloaded diet in adolescence,aerobic exercise can effectively regulate the metabolic relationship between NHI and manganese,zinc,and calcium,significantly increase selenium contents in cerebral cortex,and avoid the toxicity of iron overload.Compared to IADS,manganese contents in striatum were significantly increased in IDDS,no differences were found in NHI,copper,zinc,calcium contents;Striatum NHI contents were significantly inc reased in IODS,no differences were found in manganese,copper,zinc,calcium contents.Compared to IDDS,exercise significantly decreased manganese,copper,zinc,calcium contents in striatum,no differences were found in NHI contents.No significant differences were found in NHI,manganese,copper,zinc,calcium contents in striatum of rats fed with IO D and IAD between exercise groups and sedentary groups.Exercise significantly changed the relationship between NHI and manganese,copper,and zinc in striatum of rats fed with different iron diet.The results show that in the case of iron-overloaded diet or iron-deficient diet in adolescence,aerobic exercise can effectively regulate metal ions contents and the metabolic relationship of iron storage with metal ions contents.Compared to IADS,no differences were found in NHI,manganese,copper,zinc,calcium contents of midbrain in IDDS;NHI contents in midbrain were significantly increased in IODS,no differences were found in manganese,copper,zinc,calcium contents.No significant differences were found in NHI,manganese,copper,zinc,calcium contents in midbrain of rats fed with IDD and IAD between exercise and sedentary.Compared to IODS,exercise significantly decreased NHI and calcium contents in midbrain.The results show that in the case of iron-overloaded diet in adolescence,aerobic exercise can significantly decrease iron storage and calcium contents in midbrain,and avoid the toxicity.Compared to IADS,NHI,manganese,copper contents in medulla oblongata were significantly increased in IDDS,no difference s were found in zinc,calcium contents;NHI,manganese contents in medulla oblongata were significantly increased in IO DS,no differences were found in copper,zinc,calcium contents.Compared to IDDS,exercise significantly decreased medulla oblongata calcium contents,no differences were found in NHI,manganese,copper,zinc contents.No significant differences were found in NHI,manganese,copper,zinc,calcium contents in medulla oblongata of rats fed with IAD and IOD between exercise groups and sedentary groups.The results show that in the case of iron-deficient diet in adolescence,aerobic exercise can significantly decrease calcium contents in medulla oblongata,and avoid the toxicity.2.Compared to IADS,malonaldehyde(MDA)contents in cerebral cortex were significantly increased in IDDS.Exercise significantly decreased MDA contents,hydroxyl radical scavenging activity(RSC),and increased total antioxidant ability in cerebral cortex of rats fed with IDD compared to IDDS.The results show that in the case of iron-deficient diet in adolescence,aerobic exercise can effectively regulate redox status in cerebral cortex.Compared to IADS,RSC in striatum was significantly decreased in IDDS.Exercise significantly decreased MDA contents,increased RSC,total superoxide dismutase activity as well as total antioxidant ability in striatum of rats fed with IOD compared to IO DS.The results show that in the case of iron-overloaded diet in adolescence,aerobic exercise can significantly decrease MDA contents,increase RSC,total superoxide dismutase activity,total antioxidant ability,and avoid the toxicity of iron-overloaded in striatum.3.Compared to IADS,the expression of ferritin heavy chain in cerebral cortex was significantly decreased in IDDS.Exercise did not affect the iron metabolism related proteins in cerebral cortex of rats fed with different iron diet compared to the corresponding diets of sedentary group.The results show that in the case of iron-overloaded diet or iron-deficient diet in adolescence,aerobic exercise can not affect the iron metabolism related proteins in cerebral cortex,and maintain the iron homeostasis in cerebral cortex.4.Compared to IADS,NHI contents in spleen were significantly decreased in IDDS;no differences were found in NHI contents of spleen in IO DS.No significant differences were found in NHI contents in spleen of rats fed with IDD and IAD between exercise groups and sedentary groups.Exercise significantly increased NHI contents in spleen of rats fed with IOD compared to IO DS.The results show that in the case of iron-overloaded diet in adolescence,aerobic exercise can significantly increase spleen iron storage,and aggravate the iron toxicity of spleen. |
PDF Full Text Request