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Beta-thalassemia (BT) is a hereditary disease caused by abnormal hemoglobin synthesis with consequent ineffective erythropoiesis. Patients with thalassemia major are dependent on long-term blood transfusions with associated long-term complications such as iron overload (IO). This excess iron can result in tissue damage, impaired organ function, and increased morbidity. Growing evidence has demonstrated that IO contributes to impairment of the bone marrow (BM) microenvironment that largely impacts the function of BM mesenchymal stem cells, hematopoietic stem cells, and endothelial cells. In this article, we review recent progress in the understanding of iron metabolism and the perniciousness induced by IO. We highlight the importance of understanding the cross-talk between BM stem cells and the BM microenvironment, particularly the pathological effect of IO on BM stem cells and BT-associated complications. We also provide an update on recent novel therapies to cure transfusion-dependent beta-thalassemia and iron overload-induced complications for their future clinical application., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Competing Interests: Conflict of interest The authors declare no conflicts of interest that pertain to this work. Please refer to the accompanying ICMJE disclosure forms for further details.

Introduction: Iron is a crucial element necessary for blood formation in the body and its normal growth. However, irregular metabolism of iron due to absence of an elimination mechanism may deposit excess iron in the organs (iron overload) leading to metabolic disorders. Interactions between the iron regulatory peptide hormone, hepcidin and the iron exporter ferroportin plays major role in regulating the iron metabolism. Mutations in the ferroportin encoding genes, and dysregulation of hepsidin production often results in iron overload resulting in conditions like hemochromatosis, β-thalassemia, and sickle cell anemia. Until today, there is no efficacious treatment available for managing iron overload targeting ferroportin inhibition via oral administration., Areas Covered: Novel salts of substituted benzoimidazole compounds useful for the prophylaxis and/or treatment of iron overload are claimed. These compounds act as hepcidin mimetic and inhibit the ferroportin thereby preventing iron overload. The claimed actives are useful in the treatment of disease conditions such as neurodegenerative and cardiac diseases triggered by iron overload. Preclinical studies of these salts on mouse model are also discussed., Expert Opinion: Prevention and/or treatment of iron overload is critical. The claimed compounds are the first oral drug candidate to treat iron overload and reach the pre-clinical development stage.

Iron (Fe) is used in various cellular functions, and a constant balance between its uptake, transport, storage, and use is necessary to maintain its homeostasis in the body. Changes in Fe metabolism with a consequent overload of this metal are related to neurological changes and cover a broad spectrum of diseases, mainly when these changes occur during the embryonic period. This work aimed to evaluate the effect of exposure to Fe overload during the embryonic period of Drosophila melanogaster. Progenitor flies (male and female) were exposed to ferrous sulfate (FeSO 4 ) for ten days in concentrations of 0.5, 1, and 5 ​mM. After mating and oviposition, the progenitors were removed and the treatment bottles preserved, and the number of daily hatches and cumulative hatching of the first filial generation (F1) were counted. Subsequently, F1 flies (separated by sex) were subjected to behavioral tests such as negative geotaxis test, open field test, grooming, and aggression test. They have evaluated the levels of dopamine (DA), serotonin (5-HT), octopamine (OA), tryptophan and tyrosine hydroxylase (TH), acetylcholinesterase, reactive species, and the levels of Fe in the progenitor flies and F1. The Fe levels of F1 flies are directly proportional to what is incorporated during the period of embryonic development; we also observed a delay in hatching and a reduction in the number of the hatch of F1 flies exposed during the embryonic period to the 5mM Fe diet, a fact that may be related to the reduction of the cell viability of the ovarian tissue of progenitor flies. The flies exposed to Fe (1 and 5 ​mM) showed an increase in locomotor activity (hyperactivity) and a significantly higher number of repetitive movements. In addition to a high number of aggressive encounters when compared to control flies. We can also observe an increase in the levels of biogenic amines DA and 5-HT and an increase in TH activity in flies exposed to Fe (1 and 5 ​mM) compared to the control group. We conclude that the hyperactive-like behavior demonstrated in both sexes by F1 flies exposed to Fe may be associated with a dysregulation in the levels of DA and 5-HT since Fe is a cofactor of TH, which had its activity increased in this study. Therefore, more attention is needed during the embryonic development period for exposure to Fe overload., Competing Interests: Declaration of competing interest The authors declare that they have no known competing for financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Oral iron supplementation causes gastrointestinal side effects. Short-term alterations in dietary iron exacerbate inflammation and alter the gut microbiota, in murine models of colitis. Patients typically take supplements for months. We investigated the impact of long-term changes in dietary iron on colitis and the microbiome in mice., Methods: We fed mice chow containing differing levels of iron, reflecting deficient (100 ppm), normal (200 ppm), and supplemented (400 ppm) intake for up to 9 weeks, both in absence and presence of dextran sodium sulphate (DSS)-induced chronic colitis. We also induced acute colitis in mice taking these diets for 8 weeks. Impact was assessed (i) clinically and histologically, and (ii) by sequencing the V4 region of 16S rRNA., Results: In mice with long-term changes, the iron-deficient diet was associated with greater weight loss and histological inflammation in the acute colitis model. Chronic colitis was not influenced by altering dietary iron however there was a change in the microbiome in DSS-treated mice consuming 100 ppm and 400 ppm iron diets, and control mice consuming the 400 ppm iron diet. Proteobacteria levels increased significantly, and Bacteroidetes levels decreased, in the 400 ppm iron DSS group at day-63 compared to baseline., Conclusions: Long-term dietary iron alterations affect gut microbiota signatures but do not exacerbate chronic colitis, however acute colitis is exacerbated by such dietary changes. More work is needed to understand the impact of iron supplementation on IBD. The change in the microbiome, in patients with colitis, may arise from the increased luminal iron and not simply from colitis.

Hepatocytes are essential for maintaining the homeostasis of iron and lipid metabolism in mammals. Dysregulation of either iron or lipids has been linked with serious health consequences, including non-alcoholic fatty liver disease (NAFLD). Considered the hepatic manifestation of metabolic syndrome, NAFLD is characterised by dysregulated lipid metabolism leading to a lipid storage phenotype. Mild to moderate increases in hepatic iron have been observed in ∼30% of individuals with NAFLD; however, direct observation of the mechanism behind this increase has remained elusive. To address this issue, we sought to determine the metabolic consequences of iron loading on cellular metabolism using live cell, time-lapse Fourier transform infrared (FTIR) microscopy utilising a synchrotron radiation source to track biochemical changes. The use of synchrotron FTIR is non-destructive and label-free, and allowed observation of spatially resolved, sub-cellular biochemical changes over a period of 8 h. Using this approach, we have demonstrated that iron loading in AML12 cells induced perturbation of lipid metabolism congruent with steatosis development. Iron-loaded cells had approximately three times higher relative ester carbonyl concentration compared with controls, indicating an accumulation of triglycerides. The methylene/methyl ratio qualitatively suggests the acyl chain length of fatty acids in iron-loaded cells increased over the 8 h period of monitoring compared with a reduction observed in the control cells. Our findings provide direct evidence that mild to moderate iron loading in hepatocytes drives de novo lipid synthesis, consistent with a role for iron in the initial hepatic lipid accumulation that leads to the development of hepatic steatosis., (© 2021 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Mitochondrial DNA depletion syndrome (MDS) is a group of severe inherited disorders caused by mutations in genes, such as deoxyribonucleoside kinase (DGUOK). A great majority of DGUOK mutant MDS patients develop iron overload progressing to severe liver failure. However, the pathological mechanisms connecting iron overload and hepatic damage remains uncovered. Here, two patients' skin fibroblasts are reprogrammed to induced pluripotent stem cells (iPSCs) and then corrected by CRISPR/Cas9. Patient-specific iPSCs and corrected iPSCs-derived high purity hepatocyte organoids (iHep-Orgs) and hepatocyte-like cells (iHep) are generated as cellular models for studying hepatic pathology. DGUOK mutant iHep and iHep-Orgs, but not control and corrected one, are more sensitive to iron overload-induced ferroptosis, which can be rescued by N-Acetylcysteine (NAC). Mechanically, this ferroptosis is a process mediated by nuclear receptor co-activator 4 (NCOA4)-dependent degradation of ferritin in lysosome and cellular labile iron release. This study reveals the underlying pathological mechanisms and the viable therapeutic strategies of this syndrome, and is the first pure iHep-Orgs model in hereditary liver diseases., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Intracerebral hemorrhage (ICH) will be accompanied by the overload of iron and reactive oxygen species (ROS) following hematoma clearance. Although deferoxamine (DFO) has been widely utilized as a clinical first-line siderophore to remove the iron overload, the ROS-inducing damage still greatly limits the therapeutic effect of DFO. To address this issue, we designed and fabricated a series of dual-functional macromolecular nanoscavengers featuring high-density DFO units and catechol moieties. Note that the former units could effectively remove the iron overload, while the latter ones could efficiently deplete the ROS. The resulting nanoscavengers efficiently down-regulate the iron and ROS levels as well as significantly reduce the cell death in both iron-overloaded RAW 264.7 cells and the ICH mice model. This work suggests a novel clue for the ICH-ameliorated iron-depleting interventional therapeutic regimen.

Normal iron metabolism is an inherent feature of maintaining homeostasis. There is a wide range of iron disorders, which arise from iron deficiency or overload. In addition, disturbances in iron metabolism are observed in the course of numerous chronic diseases. Since iron is an essential constituent of hemoglobin, different types of anemia are clinical manifestations of both iron deficit or excess. This seemingly contradictory statement may be elucidated by the presence of hepcidin. Hepcidin is a primary regulator of iron metabolism in the human body. By promoting ferroportin degradation, hepcidin decreases the amount of iron in the circulation due to iron sequestration in the tissues and reduced intestinal absorption. Altered hepcidin concentration is a compensatory mechanism aimed at restoring iron homeostasis in various physiologic states, including pregnancy. However, hepcidin may also participate in the pathophysiologic background of hereditary hemochromatosis, anemia of chronic disease, myelodysplastic syndromes or β-thalassemia. Moreover, hepcidin is an acute-phase protein involved in innate immunity reactions. In our paper, we provide a comprehensive review of the physiologic and pathophysiologic functions of hepcidin. We present current knowledge on the structure, physiologic role and its expression control, as well as demonstrate the contribution of hepcidin in a state of illness. We also summarize the significance of hepcidin in normal and complicated pregnancy. Emphasizing the alterations in hepcidin upon treatment of specific diseases and their position in certain pathomechanisms, we support clinicians with practical aspects related to hepcidin.

Background: Arrhythmias and heart failure are common cardiac complications leading to substantial morbidity and mortality in patients with hemochromatosis, yet mechanistic insights remain incomplete. We investigated the effects of iron (Fe) on electrophysiological properties and intracellular Ca 2+ (Ca 2+ i ) handling in mouse left ventricular cardiomyocytes., Methods: Cardiomyocytes were isolated from the left ventricle of mouse hearts and were superfused with Fe 3+ /8-hydroxyquinoline complex (5-100 μM). Membrane potential and ionic currents including TRPC (transient receptor potential canonical) were recorded using the patch-clamp technique. Ca 2+ i was evaluated by using Fluo-4. Cell contraction was measured with a video-based edge detection system. The role of TRPCs in the genesis of arrhythmias was also investigated by using a mathematical model of a mouse ventricular myocyte with the incorporation of the TRPC component., Results: We observed prolongation of the action potential duration and induction of early and delayed afterdepolarizations in myocytes superfused with 15 µmol/L Fe 3+ /8-hydroxyquinoline complex. Iron treatment decreased the peak amplitude of the L-type Ca 2+ current and total K + current, altered Ca 2+ i dynamics, and decreased cell contractility. During the final phase of Fe treatment, sustained Ca 2+ i waves and repolarization failure occurred and ventricular cells became unexcitable. Gadolinium abolished Ca 2+ i waves and restored the resting membrane potential to the normal range. The involvement of TRPC activation was confirmed by TRPC channel current recordings in the absence or presence of functional TRPC channel antibodies. Computer modeling captured the same action potential and Ca 2+ i dynamics and provided additional mechanistic insights., Conclusions: We conclude that iron overload induces cardiac dysfunction that is associated with TRPC channel activation and alterations in membrane potential and Ca 2+ i dynamics.

Cardiac T2* MRI is used as a gold standard for cardiac iron quantification in patients with transfusion-dependent thalassemia (TDT). We hypothesized that left ventricular (LV) diastolic dysfunction would reflect the severity of iron overload and can serve as an early detection of cardiac iron deposits. A study was conducted on all patients with TDT. Hemoglobin, serum ferritin and non-transferrin bound iron, together with a complete echocardiography and cardiac T2* MRI, were performed on all patients. Seventy-seven patients with TDT were enrolled (median age 14 years). In the patient group with a mean serum ferritin of > 2500 ng/mL during the past 12 months, there were more patients with severe cardiac iron deposits than in the group with a mean serum ferritin of ≤ 2500 ng/mL. Diastolic dysfunction was absent in all patients with a serum ferritin of < 1000 ng/mL. All patients with cardiac T2* ≤ 20 ms had grade III LV diastolic dysfunction. However, twenty-one percent of patients with cardiac T2* > 20 ms had LV diastolic dysfunction. The differences observed in pulmonary vein atrial reversal duration and mitral A-wave (PVAR-MVA) duration ≥ - 1 ms and an E/E' ratio ≥ 11 were proven to be the associated factors with the cardiac T2* ≤ 20 ms. Increased PVAR-MVA duration and increased E/E' ratio reliably reflected a severe iron overload, according to a cardiac T2* in patients with TDT. LV diastolic dysfunction can occur prior to severe cardiac iron deposition. Tissue Doppler echocardiography has the potential for the early detection of cardiac involvement in patients with TDT .

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.

Iron overload has been recently shown to be associated with a hyperadrenergic state in genetic hemochromatosis. Whether this is also the case in essential hypertension, characterized by sympathetic activation and frequently by body iron overload, is unknown. In 17 healthy normotensive controls (age 52.3±3.2 years, mean±SE), in 21 age-matched patients with hypertension with iron overload (HT+), defined by serum ferritin levels, and in 28 hypertensives without this condition, we measured efferent postganglionic muscle sympathetic nerve traffic (microneurography), heart rate and blood pressure variability (power spectral analysis), serum ferritin, and metabolic variables. Muscle sympathetic nerve traffic was significantly ( P <0.02 at least) greater in HT+ than in patients with hypertension without iron overload and normotensive subjects both when expressed as bursts incidence over time (41.8±1.4 versus 31.5±1.4 and 23.6±0.9 bursts/min) and as bursts corrected for heart rate (55.3±1.8 versus 42.3±1.2 and 31.7±1.2 bursts/100 heartbeats). In HT+, low-frequency systolic blood pressure variability was significantly reduced. In HT+, but not in the other 2 groups, muscle sympathetic nerve traffic was significantly related to serum ferritin ( r =0.51, P <0.03), transferrin saturation ( r =0.47, P <0.03), and hepatic iron load ( r =0.76, P <0.0001, magnetic resonance imaging), as well as to homeostatic model assessment index values ( r =0.46, P <0.05). These data provide the first evidence that in HT+ elevated serum ferritin is associated with a hyperadrenergic state of greater magnitude than the one seen in patients with hypertension without iron overload. They also show that the potentiation of the sympathetic activation detected in HT+ is related to elevated serum ferritin and to the associated metabolic alterations, possibly participating in the increased cardiovascular risk characterizing iron overload.

Hepatic iron overload is well known as an important risk factor for progression of liver diseases; however, it is unknown whether it can alter the susceptibility to drug-induced hepatotoxicity. Here we investigate the pathological roles of iron overload in two single-dose models of chemically-induced liver injury. Rats were fed a high-iron (Fe) or standard diet (Cont) for four weeks and were then administered with allyl alcohol (AA) or carbon tetrachloride (CCl 4 ). Twenty-four hours after administration mild mononuclear cell infiltration was seen in the periportal/portal area (Zone 1) in Cont-AA group, whereas extensive hepatocellular necrosis was seen in Fe-AA group. Centrilobular (Zone 3) hepatocellular necrosis was prominent in Cont-CCl 4 group, which was attenuated in Fe-CCl 4 group. Hepatic lipid peroxidation and hepatocellular DNA damage increased in Fe-AA group compared with Cont-AA group. Hepatic caspase-3 cleavage increased in Cont-CCl 4 group, which was suppressed in Fe-CCl 4 group. Our results showed that dietary iron overload exacerbates AA-induced Zone-1 liver injury via enhanced oxidative stress while it attenuates CCl 4 -induced Zone-3 liver injury, partly via the suppression of apoptosis pathway. This study suggested that susceptibility to drugs or chemical compounds can be differentially altered in iron-overloaded livers.

Objective: Iron is emerging as a key player in aging-associated diseases due to its propensity for driving free radical formation. Studies examining the role of iron in the pathogenesis of primary osteoarthritis (OA) are limited. Our objective was to establish a direct relationship between excess iron and OA by administering iron dextran to a guinea pig strain with decreased propensity for developing this disease., Design: Twenty, 12-week-old Strain 13 guinea pigs received either iron dextran or dextran control intraperitoneally once weekly for 4 weeks; termination occurred at 16 weeks of age. Iron levels were determined systemically (serum and liver) and within diarthrodial joints [femoral head articular cartilage and infrapatellar fat pads (IFPs) of knee joints]. One knee was collected to score structural changes associated with OA via microcomputed tomography (microCT) and histology using published grading schemes. Articular cartilage and IFPs were harvested from contralateral knees for gene expression analyses., Results: Iron overload was confirmed systemically via increased serum iron and liver iron concentration. Articular cartilage and IFPs in the iron dextran group also had higher levels of iron. Excess iron worsened knee OA using both microCT and histologic scoring systems. Gene analyses revealed that exogenous iron altered the expression of iron trafficking proteins, select cytokines, and structural components of cartilage., Conclusion: These results demonstrate that systemic iron overload caused cellular iron accumulation in the knee joint. This excess iron is associated with increased expression of local inflammatory mediators and early onset and progression of knee joint OA in Strain 13 animals., (Copyright © 2020 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Background and Purpose: Brainstem hemorrhage (BSH) is the most devastating subtype of intracerebral hemorrhage (ICH) with the highest mortality ranging from 56 % to 61.2 %. However, there is no effective medical or surgical therapy to improve its outcomes in clinic to date due to lack of understanding of its injury mechanisms. Herein, we explored the brainstem iron overload and injury in a rat model of BSH., Methods: Neurological scores were examined on day 1, 3, and 7 after modeling, and mortality of the rats was recorded to draft a survival curve. Rats were monitored by MRI using T2 and susceptibility weighted imaging (SWI) before sacrifice for examination of histology and immunofluorescence on day 1, 3, and 7., Results: BSH rats had a high mortality of 56 % and demonstrated the severe neurological deficits mimicking the clinical conditions. SWI showed that the same increasing tendency in change of hypointense area with that in iron deposition by Perls staining from day 1 to 7. Expression of heme oxygenase 1 (HO-1) and generation of reactive oxygen species (ROS) had similar tendency and both peaked on day 3. Neuronal degeneration occurred and stayed elevated from day 1 to 7, while myelin sheath injury was initially observed on day 1 but without significant difference within 7 days., Conclusions: The time courses of erythrocyte lysis, HO-1 expression, iron deposition and ROS generation are related to each other after BSH. Besides, brainstem injury including neuronal degeneration and myelin damage were observed and discussed., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The advent of techniques for the assessment of iron overload (liver T2*-MRI) has led to the awareness that focal nodular hyperplasia (FNH) represents a possible incidental finding after hematopoietic stem cell transplantation (HSCT), though its pathogenesis is still unclear., Methods: We performed a retrospective analysis of the liver T2*-MRI scans performed between 2013 and 2018 in a single pediatric HSCT Unit and recorded the number of patients with FNH (group A). Patients incidentally diagnosed with FNH at imaging performed for different clinical indications were included in group B., Results: Nine of 105 (8.6%) patients from group A were diagnosed with FNH. Group B included three patients. Overall, 12 patients were diagnosed 4.4 ± 3.1 years after HSCT. At univariate analysis, female gender (odds ratio [OR] 3.77, P = .03), moderate-to-severe iron overload (OR 6.97, P = .01), and hormone replacement therapy (HRT) administered for at least 6 months (OR 18.20, P = .0002) exposed patients to a higher risk of developing FNH. The detrimental effect of HRT was significant also at multivariate analysis (OR 7.93, P = .024). MRI-T2* values in affected patients were statistically lower than healthy controls (P < .001)., Conclusions: We confirm the high incidence of FNH among transplanted pediatric patients and demonstrate the potential pathogenic role of HRT and iron overload., (© 2019 Wiley Periodicals, Inc.)

Iron is an essential element for hemoglobin synthesis during erythropoiesis. Iron overload, in contrast, adversely affects erythropoiesis and causes organ dysfunction. Research using various animal models may help to elucidate pathophysiological mechanisms induced by excess iron. In the present study, we evaluated the relationship between iron metabolism and erythropoietic activity in the African clawed frog, Xenopus laevis . In X. laevis , both erythropoiesis and iron metabolism occur in the liver. First, we developed a method to quantify iron levels in the liver and plasma using 2-nitroso-5-[N-n-propyl-N-(3-sulfopropyl) amino] phenol (Nitroso-PSAP). We then measured iron levels and analyzed hematopoietic parameters in frogs that were orally administered sodium ferrous citrate (SFC). The hepatic iron level increased in the SFC group, but the number of erythrocytes, hematocrit, and hemoglobin concentration did not change, suggesting that the regulation of the production and release of mature erythrocytes in the liver was not directly affected by dietary iron. At four days after administration of 2 mg/kg SFC, the number of immature erythrocytes decreased in the liver. Interestingly, atypical blood cells with hyper-segmented nuclei were observed, identified by acridine orange cell staining; these atypical blood cells were hardly detectable under the steady state. Compared with previously reported results in mice, the increase in the hepatic iron levels was small, but our results indicate that SFC affects hematopoietic activity. These results establish a novel model for iron metabolism and provide new insights into the relationship between iron metabolism and erythropoiesis in vertebrates.

To investigate the biological processes affected by long-term iron supplementation, newly hatched silkworms were exposed to high iron mulberry diet (10 and 100 ppm) and its effect on silkworm transcriptom was determined. The results showed that the silkworm was responsive to iron by increasing iron concentration and ferritin levels in the hemolymph and by regulating the expression of many other genes. A total of 523 and 326 differentially expressed genes were identified in 10 and 100 ppm Fe group compared to the control, respectively. Of these genes, 249 were shared between in both the 10 ppm and 100 ppm Fe group, including 152 up-regulated and 97 down-regulated genes. These shared genes included 19 known Fe regulated, 24 immune-related, 12 serine proteases and serine proteases homologs, 41 cuticular and cuticle genes. Ten genes (carboxypeptidases A, serine protease homologs 85, fibrohexamerin/P25, transferrin, sex-specific storage-protein 2, fungal protease inhibitor F, insect intestinal mucin, peptidoglycan recognition protein B, cuticle protein CPH45, unknown gene) were involved in the regulation of iron overload responses., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The aim of the present study was to investigate the role of ferroptosis in acute lung injury (ALI) mouse model induced by oleic acid (OA). ALI was induced in the mice via the lateral tail vein injection of pure OA. The histopathological score of lung, lung wet-dry weight ratio and the protein content of bronchoalveolar lavage fluid (BALF) were used as the evaluation indexes of ALI. Iron concentration, glutathione (GSH) and malondialdehyde (MDA) contents in the lung tissues were measured using corresponding assay kits. The ultrastructure of pulmonary cells was observed by transmission electron microscope (TEM), and the expression level of prostaglandin-endoperoxide synthase 2 (PTGS2) mRNA was detected by quantitative polymerase chain reaction (q-PCR). Protein expression levels of glutathione peroxidase 4 (GPX4), ferritin and transferrin receptor 1 (TfR1) in lung tissues were determined by Western blot. The results showed that histopathological scores of lung tissues, lung wet-dry weight ratio and protein in BALF in the OA group were higher than those of the control group. In the OA group, the mitochondria of pulmonary cells were shrunken, and the mitochondrial membrane was ruptured. The expression level of PTGS2 mRNA in the OA group was seven folds over that in the control group. Iron overload, GSH depletion and accumulation of MDA were observed in the OA group. Compared with the control group, the protein expression levels of GPX4 and ferritin in lung tissue were down-regulated in the OA group. These results suggest that ferroptosis plays a potential role in the pathogenesis of ALI in our mouse model, which may provide new insights for development of new drugs for ALI.

Objective: Although spontaneous fertility and successful pregnancies have been reported in well-chelated and transfused women with beta thalassaemia major (BTM), majority of women are subfertile due to hypogonadotropic hypogonadism (HH). Little is known about the effect of iron overload on ovarian follicles and whether ovarian reserve is affected by the disease or treatment status. This study compares the markers of ovarian reserve in women with transfusion-dependent BTM over a period of ten years with healthy women from a control population., Study Design: We performed a 10-year mixed (retrospective and prospective) longitudinal study in 17 women with transfusion-dependent BTM from our thalassaemia clinic between July 2007 to June 2017. The results were compared with 52 age-matched healthy women without any medical conditions (control population) attending our fertility clinic. Patient demographics, medical history, menstrual history, hormonal parameters (serum levels of FSH, estradiol, TSH and AMH) and antral follicle count were recorded in all women from both groups. Serum levels of ferritin, cardiac T2*, liver iron concentration, thyroid function (TSH) and liver function test results were also recorded at three different time points., Results: Serum AMH levels, estradiol levels and antral follicle count were significantly lower in women with BTM compared with the control group (p < 0.05 for all). Low AMH levels were noted in both groups of women (with and without HH) with a background of BTM. Serum AMH levels positively correlated with AFC in women with BTM., Conclusion: Serum AMH level and AFC were significantly lower in women with transfusion dependent BTM as compared to age-matched healthy controls suggesting a direct impact of the disease activity or iron overload on the ovary., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Despite the advances in the management of thalassemia major, heart disease remains the leading cause of mortality in patients afflicted with this disorder. Cardiac involvement in thalassemia encompasses a spectrum of disorders including myocardial dysfunction, arrhythmias, pulmonary hypertension, and peripheral vascular disease. Although cardiac siderosis (accumulation of iron in cardiac myocytes) as a consequence of repeated blood transfusions is deemed to be the main etiologic factor for myocardial dysfunction in transfusion-dependent patients, the significance of other pathophysiologic mechanisms is being increasingly recognized especially in non-transfusion dependent patients. Management of cardiac complications in thalassemia major hinges on the treatment of the underlying pathophysiology, which often is unmitigated iron overload. The prevalence and predictors of cardiac complications in 'ex-thalassaemics' [thalassaemic patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) is unknown at present. In this review, we look at the pathogenesis of cardiac involvement in patients with beta-thalassemia major, the advances in the management of these patients and the future prospects.

Background: Cardiac iron overload following liver transplantation in patients without hemochromatosis but with severe hepatic iron deposition has been reported to result in heart failure and/or death in case reports and small case series. However, the frequency and causes of cardiac iron overload following liver transplantation and its relationship to cardiac dysfunction in patients without severe hepatic iron deposition are unclear., Methods: The primary inclusion criteria for this study were liver transplantation followed by autopsy or cardiac transplantation within 1 year. Cases of known hemochromatosis were excluded. Iron stains were performed on left ventricular myocardium from either the autopsy or surgically resected heart, as well as the surgically resected liver., Results: Nineteen cases met the study criteria: 18 autopsies and 1 case of cardiac transplantation. None of the resected livers evaluated showed severe iron deposition. Myocardial iron deposition was identified in 7 (37%) of the cases. The presence of myocardial iron deposition was not significantly associated with the grade of hepatic iron deposition, or the pre-liver transplantation serum iron or ferritin levels. However, in the patients with myocardial iron deposition, there were trends toward higher pretransplant transferrin saturation (TSAT) and more units of red blood cells transfused (uRBC). The product of the TSAT multiplied by the uRBC was significantly greater in the patients with myocardial iron deposition [4700 (3100-9800) vs. 680 (400-2300), median (interquartile range), P=.003]. New reduced left ventricular ejection fraction (<50%) following liver transplantation occurred in four of five patients with myocardial iron deposition, compared with zero of eight patients without myocardial iron deposition (P=.007)., Conclusions: In this series of patients without severe hepatic iron deposition, cardiac iron overload was associated with cardiac dysfunction following liver transplantation and was related to the product of the pre-liver transplant TSAT multiplied by the number of uRBC transfused during and following the surgery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Hereditary hemochromatosis (HH) is an autosomal recessive disorder of iron metabolism characterized by increased iron absorption and tissue deposition. Three loss-of-function mutations in the hemochromatosis gene (HFE), namely, C282Y (c.845G>A), H63D (c.187C>G), and S65C (c.193A>T), account for the vast majority of HH cases. These mutations cause alterations in HFE membrane expression, structure, and/or activity, leading to dysregulation of iron absorption. It is well established that the phenotypic expression of HFE mutations varies markedly. Herein, we describe a 64-year-old Caucasian woman with a reported history of hemochromatosis. The father of the patient had died of complications due to iron overload. Testing of HFE codon C282Y, H63D, and S65C mutations showed heterozygous C282Y. The patient had significantly elevated transferrin saturation (TS) and serum ferritin (SF) levels. Her liver function test results showed elevated alanine transaminase (ALT) and aspartate aminotransferase (AST) levels. The patient has been treated with regular phlebotomy to prevent the clinical manifestations of hemochromatosis., (© American Society for Clinical Pathology 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Disease-related complications and management are different among patients with thalassemia. This study was aimed to review the prevalence, clinical risk factors for the complications and the management in patients with thalassemia in Thailand. A multicenter cross-sectional study was conducted in patients with thalassemia aged ≥ 18 years old. Thalassemia-related complications and management were reviewed. The clinical parameters significantly associated with the complications were analyzed by logistic regression methods. The prevalence of thalassemia-related complications was 100% in patients with transfusion-dependent thalassemia (TDT) and 58.8% in patients with non-transfusion-dependent thalassemia (NTDT). Advanced age was statistically associated with extramedullary hematopoiesis in both TDT and NTDT patients. Splenectomy was a significant risk factor for pulmonary hypertension in both groups of patients. Severe iron overload started earlier in patients with TDT than NTDT and was associated with diabetes mellitus (adjusted odds ratio (AOR) = 6.2, p-value = 0.02). Disease-related complications are more prevalent in patients with TDT than patients with NTDT. Splenectomy and advanced age were important risk factors for developing major complications in both groups. Early screening and management for specific disease-related complications should be considered in patients with thalassemia according to their clinical risk factors., Competing Interests: No Novartis or any pharmaceutical company products nor honoraria were used to conduct any of the research as part of this publication. Chuncharunee S has received research funding and honoraria from Novartis Pharmaceuticals, Janssen-Cilag, Roche, and Celgene. Teawtrakul N received honoraria from Novartis and Janssen-Cilag. Siritanaratkul N. received research funding and honoraria from Novartis, Janssen-Cilag, Roche, and Pfizer. The remaining author declares no competing financial interests. There are no patents, products in development or marketed products to declare. This does not alter our adherence to the PLOS ONE policies on sharing data and materials.

The management of iron overload in thalassemia has changed dramatically since the implementation of magnetic resonance imaging, which allows detection of preclinical iron overload and prevention of clinical complications. This study evaluated the effect of deferasirox (DFX), the newest once-daily oral chelator, on cardiac function, iron overload and cardiovascular events over a longer follow up in a "real world" setting. Longitudinal changes in cardiac magnetic resonance T2*, cardiac function parameters and cardiovascular clinical events were assessed in a cohort of 98 TM patients exposed to DFX for a mean of 6.9 years (range 1.8-11.6 years). No cardiac death or incident heart failure occurred. Cardiac T2* significantly increased (+2.6 ± 11.9 msec; P = 0.035) in the whole population, with a significantly greater increase (+11.6 ± 15.5 msec, P = 0.019) in patients with cardiac iron overload (T2* <20 ms). A significant improvement in left-ventricular ejection fraction (LVEF) (from 50.6 ± 6 to 60.2 ± 5; P = 0.001) was observed in 11 (84.6%) out of 13 patients who normalized cardiac function (LVEF >56%). Arrhythmias were the most frequent cardiac adverse event noted but none led to DFX discontinuation. Our data indicate that DFX is effective in maintaining cardiac iron level in the normal range and in improving cardiac iron overload. No heart failure or cardiac death was reported over this longer observation up to 12 years. For the first time, a DFX-induced improvement in LVEF was observed in a subgroup of patients with abnormal cardiac function at baseline, a preliminary observation which deserves further evaluation., (© 2018 Wiley Periodicals, Inc.)

Intrauterine transfusion is one of the mainstays of treatment in isoimmunised pregnancies guided by the changes in middle cerebral artery Doppler of the fetus. The common postnatal complications associated with Rh isoimmunisation are high unconjugated bilirubin requiring blood exchange transfusions, cholestasis due to bile inspissation, thrombocytopenia and anaemia. Hyperferritinaemia is an uncommon adverse effect observed in Rh isoimmunised pregnancies. In this case report, we describe the clinical course of a Rh isoimmunised neonate with hyperferritinaemia and transfusion acquired cytomegalovirus disease which resolved. Iron chelation therapy was not necessary., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Iron overload pathophysiology has benefited from significant advances in the knowledge of iron metabolism and in molecular genetics. As a consequence, iron overload nosology has been revisited. The hematologist may be confronted to a number of iron overload syndromes, from genetic or acquired origin. Hemochromatoses, mostly but not exclusively related to the HFE gene, correspond to systemic iron overload of genetic origin in which iron excess is the consequence of hepcidin deficiency, hepcidin being the hormone regulating negatively plasma iron. Iron excess develops following hypersideremia and the formation of non-transferrin-bound iron, which targets preferentially parenchymal cells (hepatocytes). The ferroportin disease has a totally different iron overload mechanism consisting of defective egress of cellular iron into the plasma, iron deposition taking place mostly within the macrophages (spleen). Hereditary aceruloplasminemia is peculiar since systemic iron overload involves the brain. Two main types of acquired iron overload can be seen by the hematologist, one related to dyserythropoiesis (involving hypohepcidinemia ), the other related to multiple transfusions (thalassemias, myelodysplasia, hematopoietic stem cell transplantation). Congenital sideroblastic anemias, either monosyndromic (anemia) or polysyndromic (anemia plus extra-hematological syndromes), develop both compartimental iron excess within the erythroblast mitochondria, and systemic iron overload (through dyserythropoiesis and/or transfusions)., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Intracellular ferritin is known to store iron, an essential element in an array of physiological processes. But what purpose does serum ferritin serve, what controls ultra-high hyperferritinaemia (ferritin levels above 4000 ng/ml), and finally why is it raised in inflammatory diseases, the most impressive being haemophagocytic lymphohistiocytosis? This paper proposes a hypothesis and model to explain the above questions. Serum ferritin has some unfamiliar physiological properties. It dampens severe inflammation by inhibiting lymphocyte activity, hinders bacterial growth by acting as an iron chelator and slows malignant growth by having an antiangiogenic effect. Therefore, serum ferritin is effective at modulating many conditions and could be a desired physiological process in malignancy or infection. The proposed theory is that phagocytic cells fuse with pathological native cells in much the same way as macrophages do when forming multinucleated giant cells. The pathological cells can be "infected" by intracellular pathogens or the malignant phenotype. These fusion cells result in a massive upregulation of exclusive features of macrophage activity such as phagocytosis, iron metabolism and ferritin release. Dysfunctional mitochondria are critical to this process, Pathological cells that contain dysfunctional mitochondria "infect" phagocytic mitochondrial following cellular fusion, resulting in ferritin release. The key evidence suporting this idea: macrophages are the source of ferritin secretion; they have intimate contact with known triggers of HLH, allowing for fusion hybrids, and they commonly fuse with cells. It is also argued that exclusively intracellular pathologies trigger HLH, which is a requirement for this model. HLH has features of a mitochondriopathy and finally it is debated that all the defective genes known to trigger familial-HLH can increase the likelihood of macrophage fusion. If this hypothesis is correct, the implications might discover novel diagnostic tools to detect HLH and point to avenues of targeted therapy. This is a bold theory with interesting perspectives on cell biology and clinical medicine. The paper discusses the evidence and challenges of this proposed mechanism in describing hyperferritinaemia and its relation to HLH., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Sickle Cell Disease (SCD) is characterized by defective hemoglobin synthesis, hemolytic anemia, frequent thrombosis and chronic organ damage including endocrine organs., Aim: To assess thyroid function in children with SCD in correlation and iron load., Patients and Method: This study was conducted on 40 children with SCD with iron overload (serum ferritin more than 1000 ng/ml) including 22 males and 18 females with their ages ranging from 11-14 years and mean age value of 11.63±1.36 years and 40 healthy children of matched age and sex as a control group. For all patients; complete blood count, hemoglobin electrophoresis, serum ferritin, serum iron, iron binding capacity and thyroid function including Free Thyroxine (FT4), Free Triiodothyronine (FT3), Thyroid Stimulating Hormone (TSH), Thyroid Peroxidase Antibody (TPOAb) and Thyroglobulin Antibody (TgAb) were done., Results: Significantly higher serum ferritin and iron and significantly lower Total Iron Binding Capacity (TIBC) were found in patients compared with controls (mean serum ferritin was 1665.2±1387.65ng/ml in patients versus 192.55±107.2ng/ml in controls with p-value of 0. 007, mean serum iron was 164±83.9 ug/dl in patients versus 89.5±4.5ug/dl in controls with p-value of 0.039, mean TIBC was 238±44.5ug/dl in patients versus 308±11ug/dl in controls with p-value of 0.001). Significantly higher serum TSH and significantly lower Free T3 and Free T4 were found in patients compared with controls with no significant correlation between thyroid hormones and serum ferritin (mean serum TSH was 4.61±1.2 µIU/mL in patients versus 2.11 ± 0.54 µIU /mL in controls with p-value of 0. 045, mean serum FT3 was 2.61 ±1.3 pg/mL versus 3.93±0.47pg/mL in controls with p-value of 0.027, mean serum FT4 was 0.91±0.174 ng/dL versus 1.44± 0.164 ng/dLin controls with p-value of 0.047, r = - 0. 008 and p-value was 0. 973 for correlation between free T4 and serum ferritin, r = -0. 028 and p-value was 0. 9 for correlation between TSH and serum ferritin and r= - 0.259 and p-value was 0.27 for correlation betweenT3 and serum ferritin). There were no significant differences between patients and controls regarding thyroid peroxidase antibody and thyroglobulin antibody (mean serum thyroid peroxidase antibody was 22.45± 4.32 in patients versus 22.45 ± 3.21 in controls with p-value of 0.98 while mean serum thyroglobulin antibody was 12.32 ± 2.65 in patients versus 12.99 ± 2.34 in controls with p-value of 0.76., Conclusion: Thyroid hormones deficiency may occur in some patients with SCD., Recommendations: Regular assessment of thyroid function in children with SCD may be recommended as they are more vulnerable to develop hypothyroidism and may require replacement therapy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Iron is a 'one-way' element and the primary point of regulation of body iron stores is at the level of intestinal iron absorption. Repeated blood transfusions for congenital anaemias bypass this regulatory checkpoint and inevitably lead to iron overload in the long-term. Iron overload causes multi-organ dysfunction of the heart, liver, pancreas and joints. It also causes reproductive toxicity primarily through its damaging effect on the anterior pituitary leading to hypogonadotrophic hypogonadism. Another less understood mechanism of reproductive toxicity is direct gonadal damage of excess free iron. In this article, we present the case of a 24-year-old woman with Diamond-Blackfan anaemia who presented to our unit seeking fertility assistance. The evaluation revealed a combination of hypogonadotrophic hypogonadism and reduced ovarian reserve along with evidence of severe iron overload. A literature search along with input from clinical experts has allowed us to counsel the patient to help her make an informed choice. A multi-disciplinary approach which would include initial optimization of pre-conceptional health with aggressive iron chelation therapy and subsequent ovulation induction with gonadotrophins has been planned, failing which, egg donation may be the only viable alternative.

Objective: Despite the high frequency of HFE gene mutations in Western Europe, widespread screening for HFE hemochromatosis is not recommended due to its variable phenotype. Joint pain and a premature osteoarthritis-like disease including the hip joints are the most frequent manifestation in patients with HFE hemochromatosis and iron overload. Therefore, screening of patients with severe osteoarthritis of the hip could identify patients with HFE hemochromatosis., Methods: In this prospective cross-sectional study, 940 patients aged <70 years with end-stage osteoarthritis of the hip undergoing elective joint replacement surgery were screened for HFE hemochromatosis and compared to age- and sex-matched controls., Results: No greater prevalence of C282Y homozygosity mutation or elevated serum ferritin or transferrin saturation levels was found in the study cohort with severe osteoarthritis of the hip than in controls from the general population., Conclusion: Our screening approach could not identify an increased prevalence of HFE gene mutations and iron overload in younger patients with severe osteoarthritis of the hip., Competing Interests: The authors have declared that no competing interests exist.

Background: Patients with acute myeloid leukemia (AML) undergoing consolidation with autologous stem cell transplantation (ASCT) depend on the successful mobilization of peripheral blood stem cells. However, the factors affecting the mobilization potential in AML patients and, in particular, the effect of transfusion-related iron overload on peripheral blood stem cell mobilization are largely unknown., Study Design and Methods: We investigated the association of varying levels of iron overload and stem cell mobilization efficacy in consecutive AML patients after two induction cycles., Results: A total of 113 AML patients in early first complete remission underwent the mobilization procedure. While 84 (74.3%) patients had serum ferritin levels exceeding 1000 μg/L, 26 (23.0%) patients had levels even higher than 2000 μg/L. Iron overload correlated with the number of preceding red blood cell transfusions and inversely correlated with circulating CD34+ cell levels (p = 0.04) at apheresis. Finally, the median progression-free and overall survival rates of patients with ferritin levels of higher than 2000 μg/L were shorter with 332 days versus 2156 days (p = 0.04) and 852 days versus 2235 days (p = 0.04), respectively., Conclusion: Our data suggest that transfusion-related iron overload is suppressing the mobilization potential and is associated with inferior outcome in AML., (© 2018 AABB.)

Although iron excess is toxic to the vasculature and even that pulmonary hypertension has been reported in this scenario, the role of iron overload per se remains to be clarified. This study aimed to test the effects of chronic iron-overload in rats on the morphophysiology of resistance pulmonary arteries (RPA) and right ventricle (RV) remodeling. Rats were injected with saline or iron-dextran (10, 100 and 200 mg/kg/day i.p.) for 28 days. Our results indicated increased circulating iron with significant lung deposits. Moreover, rats treated with the highest dose exhibited RV dysfunction and hypertrophy; inward remodeling and increased vasoconstriction of the RPA. Vascular hyperreactivity was accompanied by reduced nitric oxide (NO), and was reversed by incubation with Dimethylsulfoxide, Catalase and Tempol. The NADPH oxidase subunit gp91phox was increased due to iron-overload, and incubation with angiotensin II type-1 receptor (AT1) antagonist losartan not only reduced oxidative stress but also restored vascular function. Thus, we concluded that AT1 pathway plays a role in pulmonary vascular dysfunction by increasing oxidative stress and reducing NO bioavailability, thereby contributing to vascular remodeling and pulmonary hypertension of iron-overload. This finding should instigate future studies on the beneficial impacts of in vivo blockade of AT1 receptor under iron overload., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Beta-propeller protein-associated neurodegeneration is a subtype of monogenic neurodegeneration with brain iron accumulation caused by de novo mutations in WDR45. The WDR45 protein functions as a beta-propeller scaffold and plays a putative role in autophagy through its interaction with phospholipids and autophagy-related proteins. Loss of WDR45 function due to disease-causing mutations has been linked to defects in autophagic flux in patient and animal cells. However, the role of WDR45 in iron homeostasis remains elusive. Here we studied patient-specific WDR45 mutant fibroblasts and induced pluripotent stem cell-derived midbrain neurons. Our data demonstrated that loss of WDR45 increased cellular iron levels and oxidative stress, accompanied by mitochondrial abnormalities, autophagic defects, and diminished lysosomal function. Restoring WDR45 levels partially rescued oxidative stress and the susceptibility to iron treatment, and activation of autophagy reduced the observed iron overload in WDR45 mutant cells. Our data suggest that iron-containing macromolecules and organelles cannot effectively be degraded through the lysosomal pathway due to loss of WDR45 function.

Iron accumulation in the brain has been recognized as a common feature of both normal aging and neurodegenerative diseases. Cognitive dysfunction has been associated to iron excess in brain regions in humans. We have previously described that iron overload leads to severe memory deficits, including spatial, recognition, and emotional memory impairments in adult rats. In the present study we investigated the effects of neonatal iron overload on proteins involved in apoptotic pathways, such as Caspase 8, Caspase 9, Caspase 3, Cytochrome c, APAF1, and PARP in the hippocampus of adult rats, in an attempt to establish a causative role of iron excess on cell death in the nervous system, leading to memory dysfunction. Cannabidiol (CBD), the main non-psychotropic component of Cannabis sativa, was examined as a potential drug to reverse iron-induced effects on the parameters analyzed. Male rats received vehicle or iron carbonyl (30 mg/kg) from the 12th to the 14th postnatal days and were treated with vehicle or CBD (10 mg/kg) for 14 days in adulthood. Iron increased Caspase 9, Cytochrome c, APAF1, Caspase 3 and cleaved PARP, without affecting cleaved Caspase 8 levels. CBD reversed iron-induced effects, recovering apoptotic proteins Caspase 9, APAF1, Caspase 3 and cleaved PARP to the levels found in controls. These results suggest that iron can trigger cell death pathways by inducing intrinsic apoptotic proteins. The reversal of iron-induced effects by CBD indicates that it has neuroprotective potential through its anti-apoptotic action.

The space environment chiefly includes microgravity and radiation, which seriously threatens the health of astronauts. Bone loss and muscle atrophy are the two most significant changes in mammals after long-term residency in space. In this review, we summarized current understanding of the effects of microgravity and radiation on the musculoskeletal system and discussed the corresponding mechanisms that are related to iron overload and oxidative damage. Furthermore, we enumerated some countermeasures that have a therapeutic potential for bone loss and muscle atrophy through using iron chelators and antioxidants. Future studies for better understanding the mechanism of iron and redox homeostasis imbalance induced by the space environment and developing the countermeasures against iron overload and oxidative damage consequently may facilitate human to travel more safely in space.

Resident adipose tissue macrophages (ATMs) play multiple roles to maintain tissue homeostasis, such as removing excess free fatty acids and regulation of the extracellular matrix. The phagocytic nature and oxidative resiliency of macrophages not only allows them to function as innate immune cells but also to respond to specific tissue needs, such as iron homeostasis. MFe hi ATMs are a subtype of resident ATMs that we recently identified to have twice the intracellular iron content as other ATMs and elevated expression of iron-handling genes. Although studies have demonstrated that iron homeostasis is important for adipocyte health, little is known about how MFe hi ATMs may respond to and influence adipose tissue iron availability. Two methodologies were used to address this question: dietary iron supplementation and intraperitoneal iron injection. Upon exposure to high dietary iron, MFe hi ATMs accumulated excess iron, whereas the iron content of MFe lo ATMs and adipocytes remained unchanged. In this model of chronic iron excess, MFe hi ATMs exhibited increased expression of genes involved in iron storage. In the injection model, MFe hi ATMs incorporated high levels of iron, and adipocytes were spared iron overload. This acute model of iron overload was associated with increased numbers of MFe hi ATMs; 17% could be attributed to monocyte recruitment and 83% to MFe lo ATM incorporation into the MFe hi pool. The MFe hi ATM population maintained its low inflammatory profile and iron-cycling expression profile. These studies expand the field's understanding of ATMs and confirm that they can respond as a tissue iron sink in models of iron overload.

Objectives: Iron-burden-induced arrhythmia and heart failure are among the leading causes of morbidity and mortality in β-thalassaemia major patients. T2* cardiac magnetic resonance remains the only reliable noninvasive method for the heart iron excess assessment. We explored the role of single nucleotide polymorphisms involved in vitamin D metabolism, transport and activity and in deferasirox (DFX) metabolism on cardiac iron burden., Patients and Methods: One hundred and five β-thalassaemia patients, treated with DFX, were enrolled in the present study. Drug plasma Ctrough was measured by a high-performance liquid chromatography-ultraviolet method. Allelic discrimination was carried out using the real-time PCR., Results: CYP1A1*1189 CC, ABCG2 421 GA, CYP24A1 8620 GG and VDR TaqI CC single nucleotide polymorphisms influenced T2* values. Age, serum ferritin, ABCG2 421 GA, ABCG2 1194 +928 TC/CC, CYP24A1 22776 TT and VDR TaqI TC/CC were retained in linear regression model., Conclusion: Our results suggested, for the first time, the role of DFX and vitamin D pharmacogenetics on cardiac iron overload.

Background: An iron-overloaded state has been reported to be associated with insulin resistance. On the other hand, conditions such as classical hemochromatosis (where iron overload occurs primarily in the liver) have been reported to be associated with increased insulin sensitivity. The reasons for these contradictory findings are unclear. In this context, the effects of increased intracellular iron per se on insulin signaling in hepatocytes are not known., Methods: Mouse primary hepatocytes were loaded with iron in vitro by incubation with ferric ammonium citrate (FAC). Intracellular events related to insulin signaling, as well as changes in gene expression and hepatocyte glucose production (HGP), were studied in the presence and absence of insulin and/or forskolin (a glucagon mimetic)., Results: In vitro iron-loading of hepatocytes resulted in phosphorylation-mediated activation of Akt and AMP-activated protein kinase. This was associated with decreased basal and forskolin-stimulated HGP. Iron attenuated forskolin-mediated induction of the key gluconeogenic enzyme, glucose-6-phosphatase. It also attenuated activation of the Akt pathway in response to insulin, which was associated with decreased protein levels of insulin receptor substrates 1 and 2, constituting insulin resistance., Conclusions: Increased intracellular iron has dual effects on insulin sensitivity in hepatocytes. It increased basal activation of the Akt pathway, but decreased activation of this pathway in response to insulin., General Significance: These findings may help explain why both insulin resistance and increased sensitivity have been observed in iron-overloaded states. They are of relevance to a variety of disease conditions characterized by hepatic iron overload and increased risk of diabetes., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Hepatic iron accumulation is generally increased in the chronic hepatitis C (CHC) liver; however, the precise mechanism of such accumulation remains unclear. We evaluated iron absorption from the gastrointestinal tract of patients with CHC and control participants. We measured the expression of a panel of molecules associated with duodenal iron absorption and serum hepcidin levels to determine the mechanism of iron accumulation in the CHC liver. We enrolled 24 patients with CHC and 9 patients with chronic gastritis without Helicobacter pylori infection or an iron metabolism disorder as control participants. An oral iron absorption test (OIAT) was administered which involved a dosage of 100 mg of sodium ferrous citrate. Serum level of hepcidin-25 was measured by liquid chromatography-tandem mass spectrometry. Ferroportin 1 (FPN) mRNA was measured by RT-PCR and FPN protein was analyzed by western blot. Samples were obtained from duodenum biopsy tissue from each CHC patient and control participant. Caco-2/TC7 cells were incubated in Costar transwells (0.4  μ m pores). The OIAT showed significantly greater iron absorption in CHC patients than control participants. Serum hepcidin-25 in the CHC group was significantly lower than in the control group. Compared with control participants, duodenal FPN mRNA expression in CHC patients was significantly upregulated. The FPN mRNA levels and protein levels increased significantly in Caco-2/TC7 cell monolayers cultured in transwells with hepcidin. Lower serum hepcidin-25 levels might upregulate not only FPN protein expression but also mRNA expression in the duodenum and cause iron accumulation in patients with CHC.

Although disturbance of cardiac Ca 2+ regulation is involved in the pathophysiology of iron-overload cardiomyopathy, the obvious mechanisms involved in the dysregulation of iron-induced cardiac Ca 2+ are unclear. Moreover, the roles of the iron chelator deferiprone and the T-type calcium channel blocker efonidipine on cardiac intracellular Ca 2+ transients and Ca 2+ regulatory proteins in thalassemic mice are still unknown. We tested the hypothesis that treatment with either deferiprone or efonidipine attenuated cardiac Ca 2+ dysregulation and led to improved left ventricular (LV) function in iron-overloaded thalassemic mice. Wild-type (WT) mice and β-thalassemic (HT) mice were fed with either a normal diet (ND) or a high iron-diet (FE) for 90 days. Then, the FE-fed mice were treated with either deferiprone (75 mg/kg/day) or efonidipine (4 mg/kg/day) for 30 days. ND-fed HT mice had an increase in T-type calcium channels (TTCC) and an increased level of sarcoplasmic reticulum Ca 2+ -ATPase (SERCA), compared with ND-fed WT mice. Chronic iron feeding led to an increase in TTCC and expression of SERCA proteins in FE-fed WT mice. Moreover, chronic iron overload led to increased plasma non-transferrin bound iron (NTBI) and cardiac iron deposition, impaired cardiac intracellular Ca 2+ transients including decreased intracellular Ca 2+ transient amplitude, rising rate and decay rate, as well as impaired LV function as indicated by a decreased %LV ejection fraction (%LVEF) in both WT and HT mice. Our findings showed that treatment with either deferiprone (DFP) or efonidipine (EFO) showed similar benefits in reducing plasma NTBI and cardiac iron deposition, and improving %LVEF from 84.3 (WT) to 89.3 (DFP) and 89.2 (EFO) treatment; and from 84.2 (HT) to 88.8 (DFP) and 89.5 (EFO) treatment, however there was no improvement in the regulation of cardiac Ca 2+ in iron-overloaded thalassemic mice. These findings provide the understanding of the effects of these drugs on the iron-overloaded heart in thalassemic mice and suggest that an alternative intervention that could improve calcium regulation under this condition is needed to improve the therapeutic outcome. Moreover, whether the benefits of the TTCC blocker is via its inhibition of the TTCC alone or together with its ability to chelate iron are still unclear and need further investigation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The aim of this study was to determine the toxicological effects of excess iron in a liquid iron preparation (especially on intestinal barrier function) and the possible etiology of side effects or diseases caused by the excess iron. In study 1, forty male Sprague-Dawley rats (4-5 wk old) were subjected to oral gavage with 1 ml vehicle (0.01 mol/L HCl) or 1 ml liquid iron preparation containing 8 mg, 16 mg or 24 mg of iron for 30 d. Iron status, oxidative stress, histology (H&E staining), ultrastructure (electron microscopy) and apoptosis (TUNEL assay) in the intestines and liver were assessed. The cecal microbiota was evaluated by 16S rRNA sequencing. In study 2, twenty rats with the same profile as above were subjected to oral gavage with 1 ml vehicle or 24 mg Fe for 30 d. The intestinal barrier function was determined by in vivo studies and an Ussing chamber assay; tight junction proteins and serum pro-inflammatory cytokines were observed by enzyme-linked immunosorbent assay. In study 1, the intestinal mucosa and liver showed apparent oxidative stress. In addition, iron concentration-dependent ultrastructural alterations to duodenal enterocytes and hepatocytes and histological damage to the colonic mucosa were detected. Notably, apoptosis was increased in duodenal enterocytes and hepatocytes. Impaired intestinal barrier function and lower expression of intestinal tight junction proteins were observed, and the phenotype was more severe in the colon than in the duodenum. A trend toward higher expression of serum pro-inflammatory cytokines might indicate systemic inflammation. Furthermore, the caecal microbiota showed a significant change, with increased Defluviitaleaceae, Ruminococcaceae, and Coprococcus and reduced Lachnospiraceae and Allobaculum, which could mediate the detrimental effects of excess iron on gut health. We concluded that excessive iron exposure from liquid iron preparation induces oxidative stress and histopathological alterations in the intestine and liver. Impaired intestinal barrier function could increase iron transportation, and inflammation along with oxidative stress-enhanced liver iron deposition may cause further liver injury in a vicious circle. These effects were accompanied by lower intestinal segment damage and altered gut microbial composition of rats toward a profile with an increased risk of gut disease., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

The thalassemias are the most common single gene disorder in the world. Nowadays, the average life expectancy of patients in developed countries has increased significantly, while, there was an increase of complications. We aimed to investigate peripheral neuropathy and myopathy in this patient group using a neurophysiological study. We performed nerve conduction studies and electromyography of upper and lower extremities on 36 beta-thalassemia major (β-thal) patients. The electrophysiological findings were correlated with demographic data and laboratory parameters of the disease. Patients with β-thal present polyneuropathy or myopathy at (50%). Polyneuropathy was detected in (38.9%) and myopathy in (27.8%), while polyneuropathy and myopathy were present at (16.7%) with an overlap of the diseases in 1/3 of the patients. There was not a statistically significant correlation of polyneuropathy and myopathy with age, sex, splenectomy, nor with respect to laboratory parameters, hemoglobin, and ferritin. However, there was a statistically significant correlation of polyneuropathy and myopathy with iron overload, as recorded by the magnetic resonance imaging (MRI) of the heart and the liver. Our findings suggest that iron overload plays a key role in the pathogenesis of polyneuropathy and myopathy in β-thal patients, and performing heart and liver MRI for the prediction of such lesions in an annual basis is warranted.

Patients with hematologic malignancies undergoing chemotherapy and requiring blood transfusion usually have an elevated serum ferritin. These findings have led to the suggestion that iron overload is common and may have deleterious effects in these patients. However, the relationship between serum ferritin and parenchymal iron overload in such patients is unknown. Therefore, we measured the liver iron content (LIC) by the FerriScan® method and investigated the liver function and some endocrine tests in 27 patients with acute leukemia (AL) or myelodysplastic syndromes (MDS). Using FerriScan® method, the normal mean LIC levels are: 4.3 ± 2.9 mg Fe/g dry weight (d.w.). In our patients, the mean serum ferritin level was 1965 ± 2428 ng/mL. In our patients, the mean total iron in the blood received by them was 7177 ± 5009 mg. In 6 out of 27 patients LIC was > 7 mg Fe/g d.w. and in 11/27 serum ferritin was > 1000 ng/ml. Measuring fasting blood glucose revealed 3/27 with diabetes mellitus and 4/27 with impaired fasting glucose (IFG). All patients had normal serum concentrations of calcium, parathormone (PTH), free thyroxine (FT4) and thyrotropin (TSH). Four patients had elevated serum alanine transferase (ALT). LIC was correlated significantly with ferritin level (r = 0.5666; P < 0.001) and the cumulative amount of iron in the transfused blood (r = 0.523; P <0.001). LIC was correlated significantly with ALT (r = 0.277; P = 0.04) and fasting blood glucose (FBG) was correlated significantly with the amount of iron transfused (r = 0.52, p < 0.01) and ALT level (r = 0.44; P< 0.01). The age of patients did not correlate with LIC, FBG or ALT. In conclusions, these results contribute to our understanding of the prevalence of dysglycemia and hepatic dysfunction in relation to parenchymal iron overload in patients with hematologic malignancies undergoing chemotherapy and requiring blood transfusions.

Background: Heart failure is the biggest cause of mortality and morbidity in people with thalassemia, and iron deposition in cardiac tissue impairs cardiovascular function. Therefore, early detection of cardiac involvement is important to improve the prognosis in these individuals., Method: Two- and three-dimensional echocardiography was performed to evaluate left ventricular ejection fraction (LVEF), left ventricular volumes and diameters, and global longitudinal strain (GLS) in 130 individuals with β-thalassemia using the speckle tracking method. Magnetic resonance imaging (MRI) was carried out on both the heart and liver. The participants were divided into 2 groups based on cardiac T2* values (normal and abnormal cardiac iron load), and the correlation between cardiac T2* MRI and GLS was evaluated., Results: The statistical analysis showed a significant correlation between cardiac T2* MRI and left ventricular global longitudinal strain. There was a significant difference in global longitudinal strain (P < .0001), liver MRI T2*( P < .0001), and left ventricular ejection fraction (P < .001) between the 2 groups. The optimal cutoff value for GLS was -18.5% with sensitivity and specificity 73.0% and 63.0%, respectively (postitive predictive value = 50%, negative predictive value = 82.3%, AUC = 0.742, std. error = 0.046) which predicts T2* value of <20 ms, according to cardiac MRI., Conclusions: The participants with cardiac iron overload had a lower GLS than those without one. This suggests that GLS may be a useful method to predict myocardial iron overload particularly in β-thalassemia patients with subclinical cardiac involvement., (© 2018, Wiley Periodicals, Inc.)

Heart failure (HF) is the end stage of cardiovascular disease and is characterized by the loss of myocytes caused by cell death. Puerarin has been found to improve HF clinically, and animal study findings have confirmed its anti-cell-death properties. However, the underlying mechanisms remain unclear, especially with respect to the impact on ferroptosis, a newly defined mechanism of iron-dependent non-apoptotic cell death in HF. Here, ferroptosis-like cell death was observed in erastin- or isoprenaline (ISO)-treated H9c2 myocytes in vitro and in rats with aortic banding inducing HF, characterized by reduced cell viability with increased lipid peroxidation and labile iron pool. Interestingly, the increased iron overload and lipid peroxidation observed in either rats with HF or H9c2 cells incubated with ISO were significantly blocked by puerarin administration. These results provide compelling evidence that puerarin plays a role in inhibiting myocyte loss during HF, partly through ferroptosis mitigation, suggesting a new mechanism of puerarin as a potential therapy for HF., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Iron overload-related heart failure is the principal cause of death in transfusion dependent patients, including those with Thalassemia Major. Linking cardiac siderosis measured by T2* to therapy improves outcomes. T1 mapping can also measure iron; preliminary data suggests it may have higher sensitivity for iron, particularly for early overload (the conventional cut-point for no iron by T2* is 20ms, but this is believed insensitive). We compared T1 mapping to T2* in cardiac iron overload., Methods: In a prospectively large single centre study of 138 Thalassemia Major patients and 32 healthy controls, we compared T1 mapping to dark blood and bright blood T2* acquired at 1.5T. Linear regression analysis was used to assess the association of T2* and T1. A "moving window" approach was taken to understand the strength of the association at different levels of iron overload., Results: The relationship between T2* (here dark blood) and T1 is described by a log-log linear regression, which can be split in three different slopes: 1) T2* low, <20ms, r2 = 0.92; 2) T2* = 20-30ms, r2 = 0.48; 3) T2*>30ms, weak relationship. All subjects with T2*<20ms had low T1; among those with T2*>20ms, 38% had low T1 with most of the subjects in the T2* range 20-30ms having a low T1., Conclusions: In established cardiac iron overload, T1 and T2* are concordant. However, in the 20-30ms T2* range, T1 mapping appears to detect iron. These data support previous suggestions that T1 detects missed iron in 1 out of 3 subjects with normal T2*, and that T1 mapping is complementary to T2*. The clinical significance of a low T1 with normal T2* should be further investigated.