Iron-deficient Rats Research Articles

Maternal dietary supplementation with ferrous N-carbamylglycinate chelate affects sow reproductive performance and iron status of neonatal piglets

Iron-deficiency anemia is a public health concern that frequently occurs in pregnant mammals and neonatal offspring. Ferrous N-carbamylglycinate chelate (Fe-CGly) is a newly designed iron fortifier with proven effects in iron-deficient rats and weanling piglets. However, the effects of this new compound on pregnant mammals are unknown. Therefore, this experiment was conducted to evaluate the effects of Fe-CGly on sow reproductive performance and iron status of both sows and neonatal piglets. A total of 40 large-white sows after second parity were randomly assigned to two groups (n=20). They were receiving a diet including 80 mg Fe/kg as FeSO4 or Fe-CGly, respectively, from day 85 of gestation to parturition. The serum (day 110 of pregnancy) and placentas of sows were sampled. Litter size, mean weight of live born piglets, birth (live) litter weight, number of live born piglets, and the number of still-born piglets, mummies, and weak-born piglets were recorded. Once delivered, eight litters were randomly selected from the 20 litters per treatment, and one new-born male piglet (1.503±0.142 kg) from each selected litter was slaughtered within 3 h after birth from the selected litters, without colostrum ingestion. The serum, longissimus muscle, liver and kidneys of the piglets were collected. The iron status of the serum samples and the messenger RNA level of iron-related genes in the placenta, liver and kidney were analyzed. The results showed that litter weight of live born piglets was higher (P=0.030) in the Fe-CGly group (19.86 kg) than in the FeSO4 group (17.34 kg). Fe-CGly significantly increased placental iron concentration (P<0.05) of sows. It also significantly increased iron saturation and reduced the total iron-binding capacity of piglets (P<0.05) at birth. However, the results revealed that supplementation of Fe-CGly in sows reduced liver and kidney iron concentration of neonatal piglets (P<0.05), indicating decreased iron storage. In addition, the concentration of iron in the colostrum was not significantly changed. Therefore, the present results suggested that replacement of maternal FeSO4 supplement with Fe-CGly in the late-gestating period for sows could improve litter birth weight, probably via enhanced iron transportation in the placenta.

Preweaning iron deficiency increases non-contingent responding during cocaine self-administration in rats

Iron deficiency (ID) is the most prevalent single-nutrient deficiency worldwide. There is evidence that ID early in development (preweaning in rat) causes irreversible neurologic, behavioral, and motor development deficits. Many of these effects have been attributed to damage to dopamine systems, including ID-induced changes in transporter and receptor numbers in the striatum and nucleus accumbens. These mesolimbic dopaminergic neurons are, in part, responsible for mediating reward and thus play a key role in addiction. However, there has been relatively little investigation into the behavioral effects of ID on drug addiction. In 2002, we found that rats made ID from weaning (postnatal day 21) and throughout the experiment acquired cocaine self-administration significantly more slowly than controls and failed to increase responding when the dose of the drug was decreased. In the present study, we assessed addiction for self-administered cocaine in rats with a history of preweaning ID only during postnatal days 4 through 21, and iron replete thereafter. The results showed that while ID did not affect the number of cocaine infusions or the overall addiction-like behavior score, ID rats scored higher on a measure of continued responding for drug than did iron replete controls. This increase in responding, however, was less goal-directed as ID rats also responded more quickly to the non-rewarded manipulandum than did control rats. Thus, while ID early in infancy did not significantly increase addiction-like behaviors for cocaine in this small study, the pattern of data suggests a possible underlying learning or performance impairment. Future studies will be needed to elucidate the exact neuro-behavioral deficits that lead to the increase in indiscriminate responding for drug in rats with a history of perinatal ID.

Hematopoietic effect of fermented deer antler extract in iron deficient diet-induced anemic rats.

To assess the hematopoietic effects of fermented deer antler extract using a dietinduced anemic animal model to facilitate the utilization of fermented deer antler extract and its derived products. Thirty 3-week-old female Sprague-Dawley rats were treated for 5 weeks. The rats were randomly divided into 6 groups and treated as follows: control, saline; NFA200, non-fermented deer antler extract 200 mg/kg; NFA500, non-fermented deer antler extract 500 mg/kg; FAB200, fermented deer antler extract 200 mg/kg; FAB500, fermented deer antler extract 500 mg/kg; and PC, heme iron 0.2 mg/kg. Blood parameters, iron content in the liver and spleen, hepatic δ-aminolevulinic acid dehydrogenase (ALAD) activity and divalent metal transporter 1 (DMT1) mRNA expression were analyzed. No detectable significant differences were observed in blood parameters among groups. The decrease in the hepatic ALAD activity in anemic rats was significantly improved by fermented deer antler extract supplementation (P<0.05); however, non-fermented deer antler extract supplementation did not result in a significant improvement (P>0.05). The hepatic DMT1 mRNA expression level was increased significantly by supplementation with both the fermented deer antler extract and the non-fermented deer antler extract in a dose-dependent manner compared with nontreatment in anemic rats (P<0.05). The hematopoietic activity induced by deer antler extract in dietinduced anemic rats might be increased through the fermentation process.

Common Bean Leaves as a Source of Dietary Iron: Functional Test in an Iron-Deficient Rat Model.

Recent findings made by our group indicate that the iron content in Phaseolus vulgaris leaves is at least four times greater than in grains therefore, we evaluated the effect of supplementation with bean leaf (iron content of 275mg/kg on a dry basis) in iron-deficient rats. Anemia was induced by feeding rats with an iron-deficient diet (IDD) for 11days and iron-recovery diets were subsequently tested for 14days using a normal diet, a 10% bean leaf-supplemented IDD (BLSD) or a ferrous sulfate-supplemented IDD. Decreased levels of leukocytes (64%), erythrocytes (30%), lymphocytes (62%), granulocytes (72%), hematocrit (34%), hemoglobin (35%), and ferritin (34%) were observed in the iron-deficient rats compared to the control rats. BLSD supplementation showed the highest recovery values relative to those recorded for control rats: leukocytes (40%), erythrocytes (24%), lymphocytes (33%), granulocytes (88%), hematocrit (17%), and hemoglobin (18%), suggesting that common bean leaves could be a good source of bioavailable iron with possible immunomodulatory effects.

Iron deficiency decreases renal 25-hydroxyvitamin D3-1α-hydroxylase activity and bone formation in rats

Dietary iron intake is associated with bone metabolism in human and animals. Previous studies have suggested that iron deficiency diminishes bone formation and causes bone loss in rats, however, the detailed mechanisms remain unclear. To clarify the mechanism of the diminishing bone formation in iron deficiency, we examined the renal 25-hydroxyvitamin D3-1α-hydroxylase (1α-hydroxylase) activity and femoral expression of bone formation-related genes in iron-deficient rats. Male Wistar rats (n = 18) at 3 weeks of age were divided into three groups of six rats each. Two groups of rats were given free access to a control diet or an iron-deficient diet for 4 weeks. Rats in the third group were pair-fed the control diet, calculated as the mean food intake of the iron-deficient group. Following the treatment, compared with the control and pair-fed groups, hemoglobin and liver iron concentrations were significantly lower and heart weight was significantly higher in the iron-deficient group. Serum 1,25-dihydroxyvitamin D3 concentration and renal 1α-hydroxylase activity were significantly lower in the iron-deficient group compared with the control and pair-fed groups. Serum osteocalcin concentration and bone mineral density of the femur were also significantly lower in the iron-deficient group compared with the control and pair-fed groups. Furthermore, iron-deficient diet decreased runt-related transcription factor 2, osteocalcin, and type I collagen mRNA expression in the femur. Our findings indicate that iron deficiency reduces renal 1α-hydroxylase activity, leading to a decreased bone formation in rats.

Prenatal Choline Supplementation Diminishes Early-Life Iron Deficiency–Induced Reprogramming of Molecular Networks Associated with Behavioral Abnormalities in the Adult Rat Hippocampus

Background: Early-life iron deficiency is a common nutrient deficiency worldwide. Maternal iron deficiency increases the risk of schizophrenia and autism in the offspring. Postnatal iron deficiency in young children results in cognitive and socioemotional abnormalities in adulthood despite iron treatment. The rat model of diet-induced fetal-neonatal iron deficiency recapitulates the observed neurobehavioral deficits.Objectives: We sought to establish molecular underpinnings for the persistent psychopathologic effects of early-life iron deficiency by determining whether it permanently reprograms the hippocampal transcriptome. We also assessed the effects of maternal dietary choline supplementation on the offspring’s hippocampal transcriptome to identify pathways through which choline mitigates the emergence of long-term cognitive deficits.Methods: Male rat pups were made iron deficient (ID) by providing pregnant and nursing dams an ID diet (4 g Fe/kg) from gestational day (G) 2 through postnatal day (PND) 7 and an iron-sufficient (IS) diet (200 g Fe/kg) thereafter. Control pups were provided IS diet throughout. Choline (5 g/kg) was given to half the pregnant dams in each group from G11 to G18. PND65 hippocampal transcriptomes were assayed by next generation sequencing (NGS) and analyzed with the use of knowledge-based Ingenuity Pathway Analysis. Real-time polymerase chain reaction was performed to validate a subset of altered genes.Results: Formerly ID rats had altered hippocampal expression of 619 from >10,000 gene loci sequenced by NGS, many of which map onto molecular networks implicated in psychological disorders, including anxiety, autism, and schizophrenia. There were significant interactions between iron status and prenatal choline treatment in influencing gene expression. Choline supplementation reduced the effects of iron deficiency, including those on gene networks associated with autism and schizophrenia.Conclusions: Fetal-neonatal iron deficiency reprograms molecular networks associated with the pathogenesis of neurologic and psychological disorders in adult rats. The positive response to prenatal choline represents a potential adjunctive therapeutic supplement to the high-risk group.

Dietary-induced gestational iron deficiency inhibits postnatal tissue iron delivery and postpones the cessation of active nephrogenesis in rats.

Gestational iron deficiency (ID) can alter developmental programming through impaired nephron endowment, leading to adult hypertension, but nephrogenesis is unstudied. Iron status and renal development during dietary-induced gestational ID (<6 mg Fe kg-1 diet from Gestational Day 2 to Postnatal Day (PND) 7) were compared with control rats (198 mg Fe kg-1 diet). On PND2-PND10, PND15, PND30 and PND45, blood and tissue iron status were assessed. Nephrogenic zone maturation (PND2-PND10), radial glomerular counts (RGCs), glomerular size density and total planar surface area (PND15 and PND30) were also assessed. Blood pressure (BP) was measured in offspring. ID rats were smaller, exhibiting lower erythrocyte and tissue iron than control rats (PND2-PND10), but these parameters returned to control values by PND30-PND45. Relative kidney iron (µg g-1 wet weight) at PND2-PND10 was directly related to transport iron measures. In ID rats, the maturation of the active nephrogenic zone was later than control. RGCs, glomerular size, glomerular density, and glomerular planar surface area were lower than control at PND15, but returned to control by PND30. After weaning, the kidney weight/rat weight ratio (mg g-1) was heavier in ID than control rats. BP readings at PND45 were lower in ID than control rats. Altered kidney maturation and renal adaptations may contribute to glomerular size, early hyperfiltration and long-term renal function.

In-Vivo Nutritional and Toxicological Evaluation of Nano Iron Fortified Biscuits as Food Supplement for Iron Deficient Anemia

Iron deficiency anemia (IDA) is a global nutritional metabolic disorder affecting majority of healthy people rather than those suffering from chronic diseases. The main reason for IDA is not the existence quantity of iron in food but its bioavailability form. The present work represents new modality to increase the intestinal absorptivity of iron through biosynthesis of biocompatible iron nanoparticles (Fe3O4) capped with vitamin C. Intestinal villi will absorb the nano particles as Vitamin C not as iron because Iron particles are coated with Vitamin C in order to overcome the limited absorptivity of iron in gut. Biocompatible magnetite nanoparticles (Fe3O4) of size range 20 ± 5 nm were synthesized and characterized by Transmission Electron Microscope (TEM) and X-Ray Diffraction (XRD). Iron Deficient anemic rats were treated with an iron free basal diet for long period and hematological indices were tested for establishing the anemic state. Three levels Nano Iron Fortified Biscuits (10 ppm, 30 ppm and 60 ppm iron) were prepared and one level of Ferric Chloride (FeCl3) fortified biscuits, 10 ppm, in addition to untreated control group nourished iron free basal diet. Results reveals that, the nano iron form promoted the growth rate and increased the nutritional quality of protein and enhance the erythropoiesis process where Hemoglobin concentration increased from 9.9 ± 1.2 g/dl to be 14.6 ± 1.1 g/dl, 16.7 ± 1.6 g/dl and 18.2 ± 2.1 g/dl For the tree levels of 10 ppm, 30 ppm and 60 ppm, respectively. While for RBCs count increased to be 6.7 ± 1.4 x 106/mm3, 7.3 ± 1.6 x 106/mm3 and 7.8 ± 1.8 x 106/mm3, respectively. Toxicological evaluation show no apparent toxicological sings with no mortality. Based on the Histopathological and biochemical examinations The present work recommend the use of 10 ppm Nano iron fortified biscuits for mild iron deficiency anemia and the 30 ppm level for more sever one to manage and control Iron deficient anemia and extra toxicological testing are still required.

Magnetic study on biodistribution and biodegradation of oral magnetic nanostructures in the rat gastrointestinal tract.

We have undertaken a magnetic study on the oral biodistribution and biodegradation of nude maghemite nanoparticles of 10 nm average size (MNP) and probiotic bacteria, Lactobacillus fermentum, containing thousands of these same nanoparticles (MNP-bacteria). Using AC magnetic susceptibility measurements of the stomach, small intestine, cecum and large intestine obtained after rat sacrifice, and iron content determination by ICP-OES, we have monitored the biodistribution and biodegradation of the maghemite nanoparticles along the gastrointestinal tract, after oral administration of both MNP and MNP-bacteria. The results revealed that the amount of magnetic nanoparticles accumulated in intestines is sensibly higher when MNP-bacteria were administered, in comparison with MNP. This confirms our initial hypothesis that the use of probiotic bacteria is a suitable strategy to assist the magnetic nanoparticles to overcome the stomach medium, and to achieve their accumulation in intestines. This finding opens doors to different applications. Since iron absorption in humans takes place precisely in the intestines, the use of MNP-bacteria as an iron supplement is a definite possibility. We have actually illustrated how the administration of MNP-bacteria to iron-deficient rats corrects the iron levels after two weeks of treatment.

Optimizing dose of aqueous extract of Mangifera indica L stem bark for treating anaemia and its effect on some disaccharidases activity in iron deficient weanling rats

Iron deficiency, the main cause of anaemia, has been linked with decreased disaccharidases activity. The highest prevalence of iron deficiency is recorded in Africa where plants, including Mangifera indica, with ethnobotanical claims of being used for the treatment of iron deficiency anaemia are ‘housed’. Although some scientific findings have been reported on the anti-anaemic potential of M. indica, none is yet to give a clearer picture of this ethnobotanical claim. This work investigates the effects of aqueous extract of M. indica stem bark on iron deficiency anaemia and disaccharidases' activities in iron deficient rat. The aqueous extract formulated into three doses, 25, 50 and 75 mg/kg body weight were administered to weanling albino rats induced with iron deficiency through diet. After four weeks of feeding the rats, the Packed Cell Volume, Haemoglobin concentration and Red Blood Cell count of the iron deficient rats were significantly reduced (P < 0.05) compared to those of healthy rats fed with iron sufficient feed. These iron status indicators were significantly increased (P < 0.05) in rats treated with the extract when compared with untreated rats. The extract also revert decreased sucrase and lactase activity in treated iron deficient rats when compared with untreated rats. The efficacy of the extract may be due to its components including iron, saponin and cardiac glycosides. This work proposed 25 mg/kg body weight as the likely non-lethal effective dose of the extract for the treatment of anaemia, though, further toxicological studies are still required to ascertain this claim.

The haemoglobin regeneration potential of fermented and unfermented &lt;i&gt;Telfaira occidentalis&lt;/i&gt; and &lt;i&gt;Gnetum africanum&lt;/i&gt; leaves in iron deficient albino rats

The effect of 10% supplementation of fermented and unfermented Telfaira occidentalis and Gnetum africanum leaves for 21 days on haemoglobin-iron, haematological parameters and serum ferritin was investigated to determined if the leaves could replenish haemoglobin in iron deficient rats. Iron deficiency significantly (p 0.05) different from the iron sufficient and leaves supplemented groups. However, haemoglobin concentration of rats on iron sufficient diet, fermented and unfermented T. occidentalis leaves and those treated with FeSO4 were significantly (p 0.05) enhance the haemoglobin regeneration potential of both leaves. © 2015 International Formulae Group. All rights reserved. Keywords: Haematological parameters, nutritional anaemia, serum ferritin, vegetables

Histological Evaluation of Megakaryocytes and Angiogenic Signaling Molecules of Bone Marrow in Experimentally Induced Iron Deficiency Anemia

Iron deficiency Anemia (IDA) induced reactive thrombocytosis occurs in children. The mechanisms involved in this phenomenon are indeterminate. Traditional cytokines involved in megakaryopoiesis such as Thrombopoietin (TPO), IL-6, and IL-11 have not been shown to be associated with this IDA induced thrombocytosis. Recent studies suggest that growth factors and signaling molecules involved in angiogenesis influence the proliferation and/or differentiation of megakaryocytes. A recent study observed that VEGFR1-mediated pathway up-regulates CXCR4 on megakaryocytes, leading to enhanced platelet production via distribution of megakaryocytes. We previously reported a statistically increased serum/plasma levels of FLT-3 and PDGF, but did not find an increase in plasma levels of TPO, VEGF and CXCR4 in an experimentally induced IDA in rats, when compared to control rats. We now present the histological evaluation of megakaryocytes and the expression of angiogenic signaling molecules, VEGF and CXCR4, in bone marrows of control and IDA rats.Six week old male Sprague-Dawley rats with jugular vein cannulas were obtained. Diet for control rats (N=9) and iron deficient diet rats (N=18) had 50 ppm and 7-8 ppm iron in Purina chow respectively. CBC, Iron Panel, and cytokines were drawn at baseline and five weeks later. On day 0, 1.5 mL of blood was drawn from iron deficient diet rats to further induce anemia. Rats were euthanized by CO2 asphyxiation and cardiac puncture. Femurs were collected, decalcified, and embedded in paraffin. Thin sliced sections were obtained to make slides. The slides were stained with hematoxylin and eosin (H&E), and with peroxidase linked anti factor VIII, VEGF, and CXCR4 according to manufacturer's instructions. The slides were evaluated under 40x microscopy. An area of 0.1 mm2 was selected and the numbers of megakaryocytes in the selected area were visually quantitated. Immunoperoxidase stained slides were analyzed using Image J software.When reviewing H&E stained bone marrow slides per 0.1 mm2, control rats contained 4 megakaryocytes, while those from IDA rats contained 11 megakaryocytes (P=0.0001). In Factor VIII stained slides, quantitative analysis of peroxidase stained megakaryocytes in control group contained 49,271 pixels, while staining in the IDA rats was 185,076 pixels (P=0.00002). When the analysis was carried out looking at vessel staining, there was a significant difference between controls (3.6) and IDA (8.5) per 0.1 mm2 (P=0.00001). In the VEGF stained slides, visual analysis of peroxidase stain showed increased intensity of staining per cell in the IDA rats. In the CXCR4 stained slides, visual inspection of the control bone marrows showed a rare small round cell weakly stained while these cells were more frequent and strongly stained in IDA rats.We successfully induced IDA in an animal model with coexisting thrombocytosis. Bone marrow slides in IDA rats documented the expected increase in number of megakaryocytes. In addition, we documented a marked increase in vascular structures of IDA rats. Contrary to our previously reported plasma levels, VEGF intensity of stain was greater within IDA rat megakaryocytes when compared to control rat megakaryocytes. We also documented an increase of CXCR4 in the bone marrows of IDA rats. However, this increase was limited to early stage megakaryocyte development cells suggesting a role during the differentiation process of megakaryocytes. Both our previous report on circulating angiogenic signaling molecules and the current histological data suggest an important role for angiogenesis in the development of IDA induced thrombocytosis. DisclosuresNo relevant conflicts of interest to declare.

Effects of ferrous carbamoyl glycine on iron state and absorption in an iron-deficient rat model.

An iron-deficient rat model was established and used to determine the effects of different iron sources on iron metabolism and absorption. Iron-deficient rats were assigned to one of three treatment groups, and their diet was supplemented with deionized water (control), Fe-CGly, or FeSO4 for 8days via intragastric administration. Blood samples were obtained for analysis of iron-related properties, and the small intestine and liver were removed for quantitative reverse transcription PCR of genes related to iron metabolism. The serum total iron-binding capacity (TIBC) levels of rats in Fe-CGly and FeSO4 supplementation groups was lower (P<0.05) than that of the rats in the control group. The rats in Fe-CGly group exhibited higher (P<0.05) plasma Fe and ferritin levels and lower (P<0.05) TIBC levels compared with the rats in FeSO4 groups. The relative expression of liver hepcidin increased (P<0.05) by tenfold and 80-fold in the Fe-CGly and FeSO4 groups, respectively, whereas divalent metal transporter 1, duodenal cytochrome b, and ferroportin 1 expression decreased (P<0.05) in the duodenum in both Fe-CGly and FeSO4 group. A comparison between Fe-CGly and FeSO4 group showed that iron regulatory protein 1 (IRP1) and iron regulatory protein (IRP2) expressions were reduced (P<0.05) in rats administered FeSO4 than in rats administered with Fe-Cgly. These results indicate that Fe-CGly rapidly improves the blood iron status and that IRP1 and IRP2 may play an important role in the intestinal absorption of Fe-CGly.

Antioxidant and anti-anemia activity of heme iron obtained from bovine hemoglobin

The industrial by-product bovine blood was used to prepare heme iron. Obtained heme iron exhibited strong in vitro antioxidant activities. Heme iron exhibited a significantly (p<0.05) higher DPPH radical scavenging activity than ascorbic acid at low concentrations. The effects of heme iron in iron deficient anemic rats were evaluated. Heme iron exhibited an effective restorative action by returning hemoglobin, red blood cell, hematocrit, mean corpuscular hemoglobin concentrations, and serum iron levels in iron-deficient animals to normal or better values. Rats in the medium dosage group (2 mg of Fe/kg of body weight) experienced better iron bioavailability than rats in other treatment groups. The activities of antioxidant enzymes were enhanced while malondialdehyde levels were reduced in iron deficient anemic rats. Heme iron obtained from bovine blood can be used as a safe and efficient new iron supplement.

Evaluation of effects of Maṇḍurabhasma on structural and functional integrity of small intestine in comparison with ferrous sulfate using an experimental model of iron deficiency anemia.

Background:The present study was planned to assess effects of Maṇḍurabhasma (MB) on structural and functional integrity of small intestine using an animal model of iron deficiency anemia (IDA) in rat.Methods:IDA was induced by giving iron deficient diet and retro-orbital bloodletting for 21 days in Wistar female rats. Rats (n = 72) were divided into six groups: (i) Control group, (ii) IDA rats, (iii) IDA rats receiving vehicle, (iv) rats receiving ferrous sulfate (40 mg/kg), (vi) rats receiving a low dose (22.5 mg/kg) of MB, (vi) rats receiving a high dose (45 mg/kg) of MB. Treatment was conducted for a period of 21 days followed by an assessment of change in hemoglobin (Hb) levels, lactase levels, lipid peroxidation activity by measuring malondialdehyde (MDA) levels and jejunal morphometry.Results:In the present study, the lactase activity was markedly reduced in iron-deficient rats. Our study has demonstrated that intestinal morphology and MDA levels were not altered in the animals with IDA as compared to normal animals. In phase II, improvement in Hb response to ferrous sulfate was accompanied by an improvement in lactase activity. However, it significantly increased MDA levels with derangement of the normal villous structure. Rats receiving a low dose of MB did not have increased MDA levels. It did not alter the jejunal villous structure and improved lactase activity, but hematinic activity was found to be less than that of ferrous sulfate. Rats receiving a high dose of MB showed significantly improved Hb as well as lactase levels. They exhibited damage to the villous structure and increased MDA levels, but the effects were significantly less as compared to ferrous sulfate group.Conclusion:Rats receiving a high dose of MB have shown improvement in hematinic and lactase levels comparable to those receiving ferrous sulfate. However, it causes lesser oxidative damage as compared to ferrous sulfate. This is an encouraging finding because it indicates the potential of MB to cause lesser gastrointestinal side effects compared to ferrous sulfate.

Beneficiary effect of nanosizing ferric pyrophosphate as food fortificant in iron deficiency anemia: evaluation of bioavailability, toxicity and plasma biomarker

NP-Fe4(P2O7)3significantly improved hemoglobin level in iron-deficient rats and Fetuin-B showed differential biological response across NP doses through plasma proteomics.

Fetal iron deficiency induces chromatin remodeling at the Bdnf locus in adult rat hippocampus.

Fetal and subsequent early postnatal iron deficiency causes persistent impairments in cognitive and affective behaviors despite prompt postnatal iron repletion. The long-term cognitive impacts are accompanied by persistent downregulation of brain-derived neurotrophic factor (BDNF), a factor critical for hippocampal plasticity across the life span. This study determined whether early-life iron deficiency epigenetically modifies the Bdnf locus and whether dietary choline supplementation during late gestation reverses these modifications. DNA methylation and histone modifications were assessed at the Bdnf-IV promoter in the hippocampus of rats [at postnatal day (PND) 65] that were iron-deficient (ID) during the fetal-neonatal period. Iron deficiency was induced in rat pups by providing pregnant and nursing dams an ID diet (4 mg/kg Fe) from gestational day (G) 2 through PND7, after which iron deficiency was treated with an iron-sufficient (IS) diet (200 mg/kg Fe). This paradigm resulted in about 60% hippocampal iron loss on PND15 with complete recovery by PND65. For choline supplementation, pregnant rat dams were given dietary choline (5 g/kg) from G11 through G18. DNA methylation was determined by quantitative sequencing of bisulfite-treated DNA, revealing a small alteration at the Bdnf-IV promoter. Chromatin immunoprecipitation analysis showed increased HDAC1 binding accompanied by reduced binding of RNA polymerase II and USF1 at the Bdnf-IV promoter in formerly ID rats. These changes were correlated with altered histone methylations. Prenatal choline supplementation reverses these epigenetic modifications. Collectively, the findings identify epigenetic modifications as a potential mechanism to explicate the long-term repression of Bdnf following fetal and early postnatal iron deficiency.

Effect of Olfactory Manganese Dose on Motor Coordination in Iron-Deficient Rats

While exposures to excessive amount of metals increase brain damage, our recent study demonstrated that manganese (Mn) exposure corrected neurobehavioral problems resulting from iron deficiency in young rats. To further characterize the dose-dependent effect of intranasal manganese on motor coordination under iron deficiency, weanling rats were fed iron-deficient (5 mg iron/kg diet) or iron-adequate control diet (50 mg/kg) for 5 weeks and manganese chloride (MnCl2) solution was intranasal instilled through the right nostril twice a week for 3 weeks. Iron-deficient rats displayed lower blood hematocrit than controls, reflecting an iron-deficient anemic condition. Mn instillation did not alter hematocrit but modestly decreased body weight. In the rotarod test, Mn-instilled rats decreased motor coordination compared with water-instilled control rats (17% decrease in the time of the first drop; P=0.042). Iron-deficiency also decreases rotarod performance. However, upon Mn instillation, iron-deficient rats stayed longer on the bar by 30% than controls (P=0.006). Interestingly, the improvement in motor coordination was associated with manganese dose. Since both iron and Mn support tyrosine hydroxylase (TH), a critical enzyme in dopamine production, we tested if TH expression was modified by Mn instillation under iron deficiency. TH levels in the striatum were increased in iron deficiency and decreased upon Mn instillation, indicating that TH is unrelated with improved motor coordination in response to olfactory Mn under iron deficiency. Taken together, these results demonstrate that either olfactory Mn exposure or iron deficiency decreases motor function but a combination of the two restores poor motor performance by Mn dose-dependent manner.

Transcriptional regulation of copper metabolism genes in the liver of fetal and neonatal control and iron-deficient rats.

Copper and iron metabolism have been known to interact for many years. We have previously shown, during pregnancy, that copper levels in the maternal liver rise as a consequence of iron deficiency, but that levels in the fetal liver decrease. In this paper, we measure expression of genes involved in copper metabolism in fetal and postnatal liver, to test whether alterations can explain this observation. Additionally, we study the extent to which gene expression changes in the latter stages of pregnancy and in the perinatal period. Ctr1 expression levels dropped to term, rising again thereafter. There was no difference in gene expression between control and iron deficient animals. Atox1 expression remained approximately stable until term, and then there was a rise to a maximum at about Day 8. Atp7a expression levels remained constant, except for a brief drop at term. Atp7b levels, in contrast, decreased from a maximum early in gestation to low levels in the term and post-natal livers. Ceruloplasmin expression appeared to be diametrically opposite to Atp7b. The other two metallochaperones showed the same pattern of expression as Atox1, with a decrease to term, a rise at Day 1, or a rise after birth followed by a brief decrease at about Day 3. None of the genes were significantly affected by iron deficiency, suggesting that changes in expression cannot explain the altered copper levels in the fetal and neonatal liver.

Effects of resistance exercise on iron absorption and balance in iron-deficient rats.

We have previously reported that resistance exercise improved the iron status in iron-deficient rats. The current study investigated the mechanisms underlying this exercise-related effect. Male 4-week-old rats were divided into a group sacrificed at the start (week 0) (n = 7), a group maintained sedentary for 6 weeks (S) or a group that performed exercise for 6 weeks (E), and all rats in the latter groups were fed an iron-deficient diet (12 mg iron/kg) for 6 weeks. The rats in the E group performed climbing exercise (5 min × 6 sets/day, 3 days/week). Compared to the week 0 rats, the rats in the S and E groups showed lower tissue iron content, and the hematocrit, hemoglobin, plasma iron, and transferrin saturation values were all low. However, the tissue iron content and blood iron status parameters, and the whole body iron content measured using the whole body homogenates of the rats, did not differ between the S group and the E group. The messenger RNA (mRNA) expression levels of hepcidin, duodenal cytochrome b, divalent metal transporter 1, and ferroportin 1 did not differ between the S group and the E group. The apparent absorption of iron was significantly lower in the E group than in the S group. Therefore, it was concluded that resistance exercise decreases iron absorption, whereas the whole body iron content is not affected, and an increase in iron recycling in the body seems to be responsible for this effect.