Transfusional iron overload and iron chelation therapy in thalassemia major and sickle cell disease

Microbiome in sickle cell disease: Pathophysiology and therapeutic insights

Sickle cell disease (SCD) is a complex genetic blood disorder characterized by abnormal haemoglobin, resulting in sickle-shaped red blood cells. While extensive research has concentrated on the genetic and physiological aspects of SCD, recent studies suggest a potential role of the human microbiome in SCD pathophysiology, adding new dimensions to its understanding. This review synthesizes current knowledge on the microbiome's involvement in SCD, focusing on alterations in the gut microbiome composition and diversity compared to healthy individuals, and their implications for disease pathogenesis. We explore how microbiome changes may contribute to vaso-occlusive crises and other complications, along with the possible associations of specific microbial taxa or markers with disease crises and clinical outcomes. Additionally, we discuss the potential of microbiome-targeted interventions, including probiotics, dietary modifications, and faecal microbiota transplantation, in managing SCD complications and improving patient outcomes. Understanding the intricate relationship between the microbiome and SCD could lead to innovative therapeutic strategies and personalized interventions for better managing the disease. This review underscores the importance of further microbiome research and its integration into holistic SCD care.

Guideline for the management of conception and pregnancy in thalassaemia syndromes: A British Society for Haematology Guideline

This comprehensive guideline, developed by a representative group of UK-based medical experts specialising in haemoglobinopathies, addresses the management of conception and pregnancy in patients with thalassaemia. A systematic search of PubMed and EMBASE using specific keywords, formed the basis of the literature review. Key terms included "thalassaemia," "pregnancy," "Cooley's anaemia," "Mediterranean anaemia," and others, covering aspects such as fertility, iron burden and ultrasonography. The guideline underwent rigorous review by prominent organisations, including the Endocrine Society, the Royal College of Obstetricians and Gynaecologists (RCOG), the United Kingdom Thalassaemia Society and the British Society of Haematology (BSH) guideline writing group. Additional feedback was solicited from a sounding board of UK haematologists, ensuring a thorough and collaborative approach. The objective of the guideline is to equip healthcare professionals with precise recommendations for managing conception and pregnancy in patients with thalassaemia.

Active Components of Pueraria lobata through the MAPK/ERK Signaling Pathway Alleviate Iron Overload in Alcoholic Liver Disease

OBJECTIVE

To delve into the primary active ingredients and mechanism of Pueraria lobata for alleviating iron overload in alcoholic liver disease.

METHODS

Pueraria lobata's potential targets and signaling pathways in treating alcohol-induced iron overloads were predicted using network pharmacology analysis. Then, animal experiments were used to validate the predictions of network pharmacology. The impact of puerarin or genistein on alcohol-induced iron accumulation, liver injury, oxidative stress, and apoptosis was assessed using morphological examination, biochemical index test, and immunofluorescence. Key proteins implicated in linked pathways were identified using RT-qPCR, western blot analysis, and immunohistochemistry.

RESULTS

Network pharmacological predictions combined with animal experiments suggest that the model group compared to the control group, exhibited activation of the MAPK/ERK signaling pathway, suppression of hepcidin expression, and aggravated iron overload, liver damage, oxidative stress, and hepatocyte death. Puerarin and genistein, the active compounds in Pueraria lobata, effectively mitigated the aforementioned alcohol-induced effects. No statistically significant disparities were seen in the effects above between the two groups receiving drug therapy.

CONCLUSION

This study preliminarily demonstrated that puerarin and genistein in Pueraria lobata may increase hepcidin production to alleviate alcohol-induced iron overload by inhibiting the MAPK/ERK signaling pathway.

Perspectives of current understanding and therapeutics of Diamond-Blackfan anemia

ABSTACT

Diamond-Blackfan anemia (DBA) is a rare congenital bone marrow failure disorder characterized by erythroid hypoplasia. It primarily affects infants and is often caused by heterozygous allelic variations in ribosomal protein (RP) genes. Recent studies also indicated that non-RP genes like GATA1, TSR2, are associated with DBA. P53 activation, translational dysfunction, inflammation, imbalanced globin/heme synthesis, and autophagy dysregulation were shown to contribute to disrupted erythropoiesis and impaired red blood cell production. The main therapeutic option for DBA patients is corticosteroids. However, half of these patients become non-responsive to corticosteroid therapy over prolonged treatment and have to be given blood transfusions. Hematopoietic stem cell transplantation is currently the sole curative option, however, the treatment is limited by the availability of suitable donors and the potential for serious immunological complications. Recent advances in gene therapy using lentiviral vectors have shown promise in treating RPS19-deficient DBA by promoting normal hematopoiesis. With deepening insights into the molecular framework of DBA, emerging therapies like gene therapy hold promise for providing curative solutions and advancing comprehension of the underlying disease mechanisms.

Salmonella Typhimurium and Pseudomonas aeruginosa Respond Differently to the Fe Chelator Deferiprone and to Some Novel Deferiprone Derivatives

The ability to obtain Fe is critical for pathogens to multiply in their host. For this reason, there is significant interest in the identification of compounds that might interfere with Fe management in bacteria. Here we have tested the response of two Gram-negative pathogens, Salmonella enterica serovar Typhimurium (STM) and Pseudomonas aeruginosa (PAO1), to deferiprone (DFP), a chelating agent already in use for the treatment of thalassemia, and to some DFP derivatives designed to increase its lipophilicity. Our results indicate that DFP effectively inhibits the growth of PAO1, but not STM. Similarly, Fe-dependent genes of the two microorganisms respond differently to this agent. DFP is, however, capable of inhibiting an STM strain unable to synthesize enterochelin, while its effect on PAO1 is not related to the capability to produce siderophores. Using a fluorescent derivative of DFP we have shown that this chelator can penetrate very quickly into PAO1, but not into STM, suggesting that a selective receptor exists in Pseudomonas. Some of the tested derivatives have shown a greater ability to interfere with Fe homeostasis in STM compared to DFP, whereas most, although not all, were less active than DFP against PAO1, possibly due to interference of the added chemical tails with the receptor-mediated recognition process. The results reported in this work indicate that DFP can have different effects on distinct microorganisms, but that it is possible to obtain derivatives with a broader antimicrobial action.

Comparison of Inline R2* MRI versus FerriScan for liver iron quantification in patients on chelation therapy for iron overload: preliminary results

OBJECTIVES

MRI quantification of liver iron concentration (LIC) using R₂ or R₂* relaxometry requires offline post-processing causing reporting delays, administrative overhead, and added costs. A prototype 3D multi-gradient-echo pulse sequence, with inline post-processing, allows immediate calculation of LIC from an R₂* map (inline R₂*-LIC) without offline processing. We compared inline R₂*-LIC to FerriScan and offline R₂* calibration methods.

METHODS

Forty patients (25 women, 15 men; age 18-82 years), prospectively underwent FerriScan and the prototype sequence, which produces two R₂* maps, with and without fat modeling, as well as an inline R₂*-LIC map derived from the R₂* map with fat modeling, with informed consent. For each map, the following contours were drawn: ROIs, whole-axial-liver contour, and an exact copy of contour utilized by FerriScan. LIC values from the FerriScan report and those calculated using an alternative R₂ calibration were the reference standards. Results were compared using Pearson and interclass correlation coefficients (PCC, ICC), linear regression, Bland-Altman analysis, and estimation of area under the receiver operator curve (ROC-AUC).

RESULTS

Inline R₂*-LIC demonstrated good agreement with the reference standards. Compared to FerriScan, inline R₂*-LIC with whole-axial-liver contour, ROIs, and FerriScan contour demonstrated PCC of 94.8%, 94.8%, and 92%; ICC 93%, 92.7%, and 90.2%; regression slopes 1.004, 0.974, and 1.031; mean bias 5.54%, 10.91%, and 0.36%; and ROC-AUC estimates 0.903, 0.906, and 0.890 respectively. Agreement was maintained when adjusted for sex, age, diagnosis, liver fat content, and fat-water swap.

CONCLUSION

Inline R₂*-LIC provides robust and comparable quantification of LIC compared to FerriScan, without the need for offline post-processing.

KEY POINTS

• In patients being treated for iron overload with chelation therapy, liver iron concentration (LIC) is regularly assessed in order to monitor and adjust therapy. • Magnetic resonance imaging (MRI) is commonly used to quantify LIC. Several R₂ and R₂* methods are available, all of which require offline post-processing. • A novel R₂* MRI method allows for immediate calculation of LIC and provides comparable quantification of LIC to the FerriScan and recently published alternative R₂* methods.

Carvedilol improves left ventricular diastolic dysfunction in patients with transfusion-dependent thalassemia

Background:

Iron overload cardiomyopathy is the most common cause of death in patients with transfusion-dependent thalassemia.

Aim:

The aim of this study was to determine the efficacy of carvedilol treatment in patients with transfusion-dependent thalassemia who had left ventricular diastolic dysfunction.

Methods:

Eighteen patients with transfusion-dependent thalassemia who had left ventricular diastolic dysfunction were enrolled. All patients had normal left ventricular systolic function and were given carvedilol with the target dose of 0.8 mg/kg/day. Ventricular function and the level of cardiac iron were assessed by echocardiography and magnetic resonance imaging at 0, 3, and 6 months.

Results:

The median age of the patients was 19 years (range 13–25 years). Four patients had severe left ventricular Grade III diastolic dysfunction and fourteen patients had Grade II diastolic dysfunction. The grade of left ventricular diastolic dysfunction was improved at 3 months after the carvedilol treatment. The Doppler parameters, including pulmonary vein atrial reversal velocity, pulmonary vein atrial reversal duration, and the difference of pulmonary vein atrial reversal and the mitral valve atrial contraction wave duration at 3 months after the carvedilol treatment, were significantly lower than these parameters before the treatment.

Conclusions:

Among patients with transfusion-dependent thalassemia who had left ventricular diastolic dysfunction without systolic dysfunction, treatment with carvedilol for 3 months was associated with improvement in Doppler parameters of left ventricular diastolic function. However, this finding and its clinical significance need to be confirmed in further double-blind controlled studies.

Parkinson's disease: Alterations in iron and redox biology as a key to unlock therapeutic strategies

A plethora of studies indicate that iron metabolism is dysregulated in Parkinson's disease (PD). The literature reveals well-documented alterations consistent with established dogma, but also intriguing paradoxical observations requiring mechanistic dissection. An important fact is the iron loading in dopaminergic neurons of the substantia nigra pars compacta (SNpc), which are the cells primarily affected in PD. Assessment of these changes reveal increased expression of proteins critical for iron uptake, namely transferrin receptor 1 and the divalent metal transporter 1 (DMT1), and decreased expression of the iron exporter, ferroportin-1 (FPN1). Consistent with this is the activation of iron regulator protein (IRP) RNA-binding activity, which is an important regulator of iron homeostasis, with its activation indicating cytosolic iron deficiency. In fact, IRPs bind to iron-responsive elements (IREs) in the 3ꞌ untranslated region (UTR) of certain mRNAs to stabilize their half-life, while binding to the 5ꞌ UTR prevents translation. Iron loading of dopaminergic neurons in PD may occur through these mechanisms, leading to increased neuronal iron and iron-mediated reactive oxygen species (ROS) generation. The "gold standard" histological marker of PD, Lewy bodies, are mainly composed of α-synuclein, the expression of which is markedly increased in PD. Of note, an atypical IRE exists in the α-synuclein 5ꞌ UTR that may explain its up-regulation by increased iron. This dysregulation could be impacted by the unique autonomous pacemaking of dopaminergic neurons of the SNpc that engages L-type Ca+2 channels, which imparts a bioenergetic energy deficit and mitochondrial redox stress. This dysfunction could then drive alterations in iron trafficking that attempt to rescue energy deficits such as the increased iron uptake to provide iron for key electron transport proteins. Considering the increased iron-loading in PD brains, therapies utilizing limited iron chelation have shown success. Greater therapeutic advancements should be possible once the exact molecular pathways of iron processing are dissected.

Transfusion and Cellular Therapy in Pediatric Sickle Cell Disease

Red blood cell (RBC) transfusion is critical in managing acute and chronic complications of sickle cell disease. Alloimmunization and iron overload remain significant complications of transfusion therapy and are minimized with prophylactic Rh and K antigen RBC matching and iron chelation. Matched sibling donor hematopoietic stem cell transplant (HSCT) is a curative therapeutic option. Autologous hematopoietic stem cell (HSC)-based gene therapy has recently shown great promise, for which obtaining sufficient HSCs is essential for success. This article discusses RBC transfusion indications and complications, transfusion support during HSCT, and HSC mobilization and collection for autologous HSCT with gene therapy.

Synthesis, characterization, biological activity and electrochemistry studies of iron(III) complex with curcumin-oxime ligand

Iron overload is a key target in drug development. This study aimed to investigate the coordination of Fe(III) ions with a curcumin-oxime ligand that may be used in the treatment of iron overload. The synthesis of the curcumin-oxime ligand and curcumin-oxime-Fe(III) complex was successfully made and characterized in its solid-state and solution-state using FT-IR, UV-Vis, elemental analysis, and 1 H-NMR. However, in this study, we investigated the apoptotic effects of the curcumin-oxime Fe (III) complex on SW480. SW480 cells were exposed to 99.2% medium for 48 hours. After 48 hours, the incubation period, cells were harvested by centrifugation and washed in phosphate-buffered saline (PBS) and lysed in radio-immunoprecipitation assay (RIPA) buffer for 20 minutes and supernatants were taken and pellets were discarded. ELISA test was used to examine the expression, and activity of cleaved caspase-3, Bax, and Bcl-2 proteins in SW480 cells. ELISA test results indicated that the activities of apoptotic proteins Bax, caspase 3 and Bcl-2 in human SW480 cell lines significantly increased in 48 hours treatment. Also, the activity of Bcl-2 was observed to decrease significantly. Catalase activities of the complex were investigated. The findings showed that the complex has a catalase activity. The findings suggest that this type of complex may constitute a new and interesting basis for the future search of new and more potent drugs. The SOD activity of the result showed that the complexes possessed a considerable SOD activity with an IC50 value of 7.685 µM. Also, when compared with the control, a complex increased the SOD levels (P < .05). Electrochemistry studies in the literature have shown that the Fe3+ /Fe2+ couple redox process occurs in low potential. This value is within the range of compounds that are expected to show superoxide dismutase activity. The Ipc /Ipa shows that one electron transport takes place in the complex. Our results suggest that curcumin-oxime may represent a new approach in the treatment of iron overload.

Recent Progress in Gene Therapy and Other Targeted Therapeutic Approaches for Beta Thalassemia

Beta-thalassemia is a genetic disorder characterized by the impaired synthesis of the betaglobin chain of adult hemoglobin. The disorder has a complex pathophysiology that affects multiple organ systems. The main complications of beta thalassemia are ineffective erythropoiesis, chronic hemolytic anemia and hemosiderosis-induced organ dysfunction. Regular blood transfusions are the main therapy for beta thalassemia major; however, this treatment can cause cardiac and hepatic hemosiderosis - the most common cause of death in these patients. This review focuses on unique future therapeutic interventions for thalassemia that reverse splenomegaly, reduce transfusion frequency, decrease iron toxicity in organs, and correct chronic anemia. The targeted effective protocols include hemoglobin fetal inducers, ineffective erythropoiesis correctors, antioxidants, vitamins, and natural products. Resveratrol is a new herbal therapeutic approach which serves as fetal Hb inducer in beta thalassemia. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy for beta thalassemia major and is preferred over iron chelation and blood transfusion for ensuring long life in these patients. Meanwhile, several molecular therapies, such as ActRIIB/IgG1 Fc recombinant protein, have emerged to address complications of beta thalassemia or the adverse effects of current drugs. Regarding gene correction strategies, a phase III trial called HGB-207 (Northstar-2; NCT02906202) is evaluating the efficacy and safety of autologous cell transplantation with LentiGlobin. Advanced gene-editing approaches aim to cut DNA at a targeted site and convert HbF to HbA during infancy, such as the suppression of BCL11A (B cell lymphoma 11A), HPFH (hereditary persistence of fetal hemoglobin) and zinc-finger nucleases. Gene therapy is progressing rapidly, with multiple clinical trials being conducted in many countries and the promise of commercial products to be available in the near future.

Reactivation of Epstein-Barr Virus by HIF-1α Requires p53

We previously reported that the cellular transcription factor hypoxia-inducible factor 1α (HIF-1α) binds a hypoxia response element (HRE) located within the promoter of Epstein-Barr virus's (EBV's) latent-lytic switch BZLF1 gene, Zp, inducing viral reactivation. In this study, EBV-infected cell lines derived from gastric cancers and Burkitt lymphomas were incubated with HIF-1α-stabilizing drugs: the iron chelator deferoxamine (Desferal [DFO]), a neddylation inhibitor (pevonedistat [MLN-4924]), and a prolyl hydroxylase inhibitor (roxadustat [FG-4592]). DFO and MLN-4924, but not FG-4592, induced accumulation of both lytic EBV proteins and phosphorylated p53 in cell lines that contain a wild-type p53 gene. FG-4592 also failed to activate transcription from Zp in a reporter assay despite inducing accumulation of HIF-1α and transcription from another HRE-containing promoter. Unexpectedly, DFO failed to induce EBV reactivation in cell lines that express mutant or no p53 or when p53 expression was knocked down with short hairpin RNAs (shRNAs). Likewise, HIF-1α failed to activate transcription from Zp when p53 was knocked out by CRISPR-Cas9. Importantly, DFO induced binding of p53 as well as HIF-1α to Zp in chromatin immunoprecipitation (ChIP) assays, but only when the HRE was present. Nutlin-3, a drug known to induce accumulation of phosphorylated p53, synergized with DFO and MLN-4924 in inducing EBV reactivation. Conversely, KU-55933, a drug that inhibits ataxia telangiectasia mutated, thereby preventing p53 phosphorylation, inhibited DFO-induced EBV reactivation. Lastly, activation of Zp transcription by DFO and MLN-4924 mapped to its HRE. Thus, we conclude that induction of BZLF1 gene expression by HIF-1α requires phosphorylated, wild-type p53 as a coactivator, with HIF-1α binding recruiting p53 to Zp.IMPORTANCE EBV, a human herpesvirus, is latently present in most nasopharyngeal carcinomas, Burkitt lymphomas, and some gastric cancers. To develop a lytic-induction therapy for treating patients with EBV-associated cancers, we need a way to efficiently reactivate EBV into lytic replication. EBV's BZLF1 gene product, Zta, usually controls this reactivation switch. We previously showed that HIF-1α binds the BZLF1 gene promoter, inducing Zta synthesis, and HIF-1α-stabilizing drugs can induce EBV reactivation. In this study, we determined which EBV-positive cell lines are reactivated by classes of HIF-1α-stabilizing drugs. We found, unexpectedly, that HIF-1α-stabilizing drugs only induce reactivation when they also induce accumulation of phosphorylated, wild-type p53. Fortunately, p53 phosphorylation can also be provided by drugs such as nutlin-3, leading to synergistic reactivation of EBV. These findings indicate that some HIF-1α-stabilizing drugs may be helpful as part of a lytic-induction therapy for treating patients with EBV-positive malignancies that contain wild-type p53.

Early detection of ventricular dysfunction by tissue Doppler echocardiography related to cardiac iron overload in patients with thalassemia

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 .

The History of Deferiprone (L1) and the Paradigm of the Complete Treatment of Iron Overload in Thalassaemia

Deferiprone (L1) was originally designed, synthesised and screened in vitro and in vivo in 1981 by Kontoghiorghes G. J. following his discovery of the novel alpha-ketohydroxypyridine class of iron chelators (1978–1981), which were intended for clinical use. The journey through the years for the treatment of thalassaemia with L1 has been a very difficult one with an intriguing turn of events, which continue until today. Despite many complications, such as the extensive use of L1 suboptimal dose protocols, the aim of chelation therapy-namely, the complete removal of excess iron in thalassaemia major patients, has been achieved in most cases following the introduction of specific L1 and L1/deferoxamine combinations. Many such patients continue to maintain normal iron stores. Thalassemia has changed from a fatal to chronic disease; also thanks to L1 therapy and thalassaemia patients are active professional members in all sectors of society, have their own families with children and grandchildren and their lifespan is approaching that of normal individuals. No changes in the low toxicity profile of L1 have been observed in more than 30 years of clinical use and prophylaxis against the low incidence of agranulocytosis is maintained using mandatory monitoring of weekly white blood cells’ count. Thousands of thalassaemia patients are still denied the cardioprotective and other beneficial effects of L1 therapy. The safety of L1 in thalassaemia and other non-iron loaded diseases resulted in its selection as one of the leading therapeutics for the treatment of Friedreich’s ataxia, pantothenate kinase-associated neurodegeneration and other similar cases. There are also increasing prospects for the application of L1 as a main, alternative or adjuvant therapy in many pathological conditions including cancer, infectious diseases and as a general antioxidant for diseases related to free radical pathology.

Protective Effect of Astragaloside IV on Hepatic Injury Induced by Iron Overload

Suitable content of iron is essential for human body, but iron overload is associated with many kinds of diseases including chronic liver damage. Recently, researchers find that iron overload promotes hepatocyte autophagy and apoptosis. However, the mechanism of iron overload in liver damage remains unclear. In this study, Lo2 cells were selected as the research object, iron dextran was a model drug, and astragaloside IV was a therapeutic drug to explore the role of iron overload. MTT assay and Annexin/PI double staining were used to measure cell viability and apoptosis. Ultrastructure was observed by transmission electron microscopy. The expression levels of apoptosis and autophagy-related proteins were determined by real-time PCR and Western Blot. The results showed that iron dextran could significantly inhibit Lo2 cell viability and increase the apoptosis rate, while astragaloside IV could reverse the inhibition of Lo2 cell viability and decrease the apoptosis rate. Transmission electron microscopy showed a significant increase in the number of autophagosomes after administration of iron dextran, and the application of astragaloside IV reduced the production of autophagosomes. LC3II/I was significantly upregulated in the model group but decreased in the astragaloside IV treatment group, and P62 showed the opposite trend. Iron dextran significantly upregulated the expression of Bax and downregulated Bcl2, while astragaloside IV reversed this trend. Finally, the inhibition of hepcidin caused by iron dextran was counteracted by astragaloside IV. In conclusion, the experimental results show that the iron overload model mainly induces excessive autophagy and apoptosis of hepatocytes, thus causing damage to hepatocytes, but astragaloside IV plays a certain therapeutic role in reversing this damage.

How I manage children with Diamond-Blackfan anaemia

Diamond-Blackfan anaemia (DBA) is a rare inherited marrow failure disorder, characterized by hypoplastic anaemia, congenital anomalies and a predisposition to cancer as a result of ribosomal dysfunction. Historically, treatment is based on glucocorticoids and/or blood transfusions, which is accompanied by significant toxicity and long-term sequelae. Currently, stem cell transplantation is the only curative option for the haematological DBA phenotype. Whereas this procedure has been quite successful in the last decade in selected patients, novel therapies and biological insights are still warranted to improve clinical care for all DBA patients. In addition to paediatric haematologists, other physicians (e.g. endocrinologist, gynaecologist) should ideally be involved in the care of this chronic condition from an early age, to improve lifelong management of haematological and non-haematological symptoms, and screen for DBA-associated malignancies. Here we provide an overview of current knowledge and recommendations for the day-to-day care of DBA patients.

Iron overload by transferrin receptor protein 1 regulation plays an important role in palmitate-induced insulin resistance in human skeletal muscle cells

Free fatty acid is considered to be one of the major pathogenic factors of inducing insulin resistance. The association between iron disturbances and insulin resistance has recently begun to receive a lot of attention. Although skeletal muscles are a major tissue for iron utilization and storage, the role of iron in palmitate (PA)-induced insulin resistance is unknown. We investigated the molecular mechanism underlying iron dysregulation in PA-induced insulin resistance. Interestingly, we found that PA simultaneously increased intracellular iron and induced insulin resistance. The iron chelator deferoxamine dramatically inhibited PA-induced insulin resistance, and iron donors impaired insulin sensitivity by activating JNK. PA up-regulated transferrin receptor 1 (tfR1), an iron uptake protein, which was modulated by iron-responsive element-binding proteins 2. Knockdown of tfR1 and iron-responsive element-binding proteins 2 prevented PA-induced iron uptake and insulin resistance. PA also translocated the tfR1 by stimulating calcium influx, but the calcium chelator, BAPTA-AM, dramatically reduced iron overload by inhibiting tfR1 translocation and ultimately increased insulin sensitivity. Iron overload may play a critical role in PA-induced insulin resistance. Blocking iron overload may thus be a useful strategy for preventing insulin resistance and diabetes.-Cui, R., Choi, S.-E., Kim, T. H., Lee, H. J., Lee, S. J., Kang, Y., Jeon, J. Y., Kim, H. J., Lee, K.-W. Iron overload by transferrin receptor protein 1 regulation plays an important role in palmitate-induced insulin resistance in human skeletal muscle cells.

Transient Elastography (TE) is a Useful Tool for Assessing the Response of Liver Iron Chelation in Sickle Cell Disease Patients

Sickle cell disease patients often need regular blood transfusions to improve both the quality of life and survival from the veno-occlusive complications of the disease. Deferasirox, a convenient long acting oral agent, has recently been introduced in clinical practice with promising efficacy.

This study aims to evaluate the association of liver stiffness and possible fibrosis with iron deposition and confirm the use of elastography as a validated test of responding to chelation with low cost and easy access.

15 patients with sickle cell disease and systemic or occasional transfusions were evaluated with MRI, transient elastography and biochemistry, for liver iron(LIC) and liver stiffness(LSM) before onset and one year after taking Deferasirox. All patients completed the study.

Our results showed improvement in hepatic iron and hepatic stiffness after chelation therapy; Furthermore ALT, AST, LDH and ferritin levels have improved after 12 months of therapy with deferasirox. During the study no serious adverse events were encountered indicating the safety of the drug.

Transient liver elastography findings correlate with serum ferritin and LIC in patients with sickle cell disease and it is a useful tool for assessing the response of liver iron chelation therapy.

Myeloperoxidase deficiency attenuates systemic and dietary iron-induced adverse effects

Iron deficiency is routinely treated with oral or systemic iron supplements, which are highly reactive and could induce oxidative stress via augmenting the activity of proinflammatory enzyme myeloperoxidase (MPO). To investigate the extent to which MPO is involved in iron-induced toxicity, acute (24 h) iron toxicity was induced by intraperitoneal administration of FeSO₄ (25 mg/kg body weight) to MPO-deficient (MpoKO) mice and their wild-type (WT) littermates. Acute iron toxicity was also assessed in WT mice pretreated with an MPO inhibitor, 4-aminobenzoic acid hydrazide. Systemic iron administration up-regulated circulating MPO and neutrophil elastase and elevated systemic inflammatory and organ damage markers in WT mice. However, genetic deletion of MPO or its inhibition significantly reduced iron-induced organ damage and systemic inflammatory responses. In contrast to the acute model, 8 weeks of 2% carbonyl iron diet feeding to WT mice did not change the levels of circulating MPO and neutrophil elastase but promoted their accumulation in the liver. Even though both MpoKO and WT mice displayed similar levels of diet-induced hyperferremia, MpoKO mice showed significantly reduced inflammatory response and oxidative stress than the WT mice. In addition, WT bone-marrow-derived neutrophils (BMDN) generated more reactive oxygen species than MPO-deficient BMDN upon iron stimulation. Altogether, genetic deficiency or pharmacologic inhibition of MPO substantially attenuated acute and chronic iron-induced toxicity. Our results suggest that targeting MPO during iron supplementation is a promising approach to reduce iron-induced toxicity/side effects in vulnerable population.

Assessment of liver and cardiac iron overload using MRI in patients with chronic anemias in Latin American countries: results from ASIMILA study

OBJECTIVES

A multicenter, noninterventional, observational study was conducted in the Latin American countries including Argentina, Brazil, Colombia, Mexico, and Venezuela to assess the prevalence of liver and cardiac iron overload using magnetic resonance imaging (MRI) in patients with chronic anemias except thalassemia.

METHODS

Patients aged >10 years with transfusion-dependent anemias, except thalassemia, either with <20 units of red blood cell (RBC) transfusions with serum ferritin (SF) levels >2000 ng/mL or with ≥20 units of RBC transfusions regardless of SF level in their lifetime, were enrolled. Iron overload was assessed using MRI.

RESULTS

Among 175 patients included, the majority had sickle cell disease (SCD; 52%), followed by aplastic anemia (AA; 17.7%), myelodysplastic syndrome (MDS; 8.6%), Diamond-Blackfan anemia (DBA; 4%), pure red cell aplasia (1.1%), and others (16.6%). Liver iron overload was observed in 76.4% of patients, while cardiac iron overload was seen in 19.2% when assessed by MRI. The prevalence of iron overload was 80.2% in patients with SCD, 73.3% in MDS, 77.4% in AA, 100% in pure red cell aplasia, 71.4% in DBA, and 68.9% in other transfusion-related disorders. A moderate correlation between liver iron concentration (LIC) and SF was observed in patients with SCD and MDS (r = 0.47 and r = 0.61, respectively). All adverse events reported were consistent with the published data for deferasirox or underlying disease.

CONCLUSION

A high prevalence of iron overload in this patient population in Latin American countries indicates that a better diagnosis and management of iron overload is required in these countries.

Transfusion-associated hazards: A revisit of their presentation

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.

Identification of a novel Na+-coupled Fe3+-citrate transport system, distinct from mammalian INDY, for uptake of citrate in mammalian cells

NaCT is a Na⁺-coupled transporter for citrate expressed in hepatocytes and neurons. It is the mammalian ortholog of INDY (I’m Not Dead Yet), a transporter which modifies lifespan in Drosophila. Here we describe a hitherto unknown transport system for citrate in mammalian cells. When liver and mammary epithelial cells were pretreated with the iron supplement ferric ammonium citrate (FAC), uptake of citrate increased >10-fold. Iron chelators abrogated the stimulation of citrate uptake in FAC-treated cells. The iron exporter ferroportin had no role in this process. The stimulation of citrate uptake also occurred when Fe³⁺ was added during uptake without pretreatment. Similarly, uptake of Fe³⁺ was enhanced by citrate. The Fe³⁺-citrate uptake was coupled to Na⁺. This transport system was detectable in primary hepatocytes and neuronal cell lines. The functional features of this citrate transport system distinguish it from NaCT. Loss-of-function mutations in NaCT cause early-onset epilepsy and encephalopathy; the newly discovered Na⁺-coupled Fe³⁺-citrate transport system might offer a novel treatment strategy for these patients to deliver citrate into affected neurons independent of NaCT. It also has implications to iron-overload conditions where circulating free iron increases, which would stimulate cellular uptake of citrate and consequently affect multiple metabolic pathways.

Improvement of chronic hepatitis B by iron chelation therapy in a patient with iron overload: A case report

RATIONALE

This report describes seroconversion of hepatitis B surface antigen (HBsAg) in a patient with marked iron overload caused by chronic hepatitis B (CHB) after receiving iron chelation therapy and discusses the role of iron chelation therapy in CHB.

PATIENT CONCERNS

Increased serum ferritin level for 2 months.

DIAGNOSIS

Secondary iron overload and CHB.

INTERVENTION

To relieve iron load of the body, the patient underwent regular phlebotomy therapy and deferoxamine (DFO) therapy. During the therapy, serum ferritin and hepatitis B virus (HBV) were monitored and the iron concentration of the liver and heart were followed by T2* of magnetic resonance imaging (MRI) scan.

OUTCOMES

Serum ferritin gradually decreased. Approximately 1 year after the therapy, HBsAg turned persistently negative.

LESSONS

Iron chelation therapy may attenuate HBV infection.

Survival and complication rates in patients with thalassemia major in Taiwan

BACKGROUND

While transfusion and iron chelation therapy for thalassemia major (TM) has improved dramatically in recent years, the consequences of this improvement (current rates of survival and TM-related complications) remain unknown.

METHODS

This nationwide population-based cohort study analyzed 2007-2011 data obtained from the Taiwanese National Health Insurance Research Database.

RESULTS

After excluding those patients receiving hematopoietic stem cell transplantation, we enrolled 454 patients with TM who received transfusion and chelation therapy (median age, 17.2 years). Among these patients, the mortality rate was 2.9% in 2007, 2.3% in 2008, 2.9% in 2009, 2.6% in 2010, and 0.7% in 2011. Heart was the most common target organ of TM-related complications. There were 80 patients (17.6%) with arrhythmia and 86 patients (18.9%) with congestive heart failure. Dysfunction of endocrine organs was common, and the most common endocrinopathy was hypogonadism (23.1%), followed by diabetes (21.2%). There were 75 patients (16.5%) with liver cirrhosis and 79 patients (17.4%) with osteoporosis.

CONCLUSIONS

Adequate red blood cell transfusion and iron chelation is available to all patients with TM in Taiwan under the universal health insurance system, and has resulted in reduction of TM-related mortality to very low levels. As these patients get older, early detection of complications and adequate intervention are important to quality-of-life improvement.

Emerging cellular and gene therapies for congenital anemias

Congenital anemias comprise a group of blood disorders characterized by a reduction in the number of peripherally circulating erythrocytes. Various genetic etiologies have been identified that affect diverse aspects of erythroid physiology and broadly fall into two main categories: impaired production or increased destruction of mature erythrocytes. Current therapies are largely focused on symptomatic treatment and are often based on transfusion of donor-derived erythrocytes and management of complications. Hematopoietic stem cell transplantation represents the only curative option currently available for the majority of congenital anemias. Recent advances in gene therapy and genome editing hold promise for the development of additional curative strategies for these blood disorders. The relative ease of access to the hematopoietic stem cell compartment, as well as the possibility of genetic manipulation ex vivo and subsequent transplantation in an autologous manner, make blood disorders among the most amenable to cellular therapies. Here we review cell-based and gene therapy approaches, and discuss the limitations and prospects of emerging avenues, including genome editing tools and the use of pluripotent stem cells, for the treatment of congenital forms of anemia. © 2016 Wiley Periodicals, Inc.

Iron Overload and Platelet Function Defects: Possible Correlation

Acquired platelet function defect might be a consequence of iron overload. Even though there are various complications of iron overload, only few reports have indicated some correlations with platelets dysfunction. We report a child with Diamond-Blackfan anemia who has significant complications from iron overload due to chronic blood transfusion, and one of these complications is acquired platelet function defect that manifests with frequent episodes of epistaxis. Therefore, we emphasize the necessity for further studies to confirm direct correlation between iron overload as a causative agent and platelets dysfunction. And we recommend screening for platelets function in patients receiving chronic blood transfusion aiming at possible prevention of any life-threatening bleeding.

Transfusion Medicine

Transfusion of various blood components can provide relief from symptomatic anemia and reduce the bleeding risks associated with low platelet counts or presence of coagulopathy. Blood components are collected from volunteer donors and processed into separate components to maximize efficient utilization of a scarce resource while also providing maximum clinical benefit. Tests including blood type and screening for clinically significant alloantibodies increase the likelihood of successful transfusion. Risks of transfusion include hypersensitivity and hemolytic transfusion reactions, transfusion-related acute lung injury, transfusion-associated circulatory overload, and transmission of infection. Indications for transfusion are reviewed along with various products available for transfusion.

Heart Rate Variability for Early Detection of Cardiac Iron Deposition in Patients with Transfusion-Dependent Thalassemia

Background

Iron overload cardiomyopathy remains the major cause of death in patients with transfusion-dependent thalassemia. Cardiac T2* magnetic resonance imaging is costly yet effective in detecting cardiac iron accumulation in the heart. Heart rate variability (HRV) has been used to evaluate cardiac autonomic function and is depressed in cases of thalassemia. We evaluated whether HRV could be used as an indicator for early identification of cardiac iron deposition.

Methods

One hundred and one patients with transfusion-dependent thalassemia were enrolled in this study. The correlation between recorded HRV and hemoglobin, non-transferrin bound iron (NTBI), serum ferritin and cardiac T2* were evaluated.

Results

The median age was 18 years (range 8–59 years). The patient group with a 5-year mean serum ferritin >5,000 ng/mL included significantly more homozygous β-thalassemia and splenectomized patients, had lower hemoglobin levels, and had more cardiac iron deposit than all other groups. Anemia strongly influenced all domains of HRV. After adjusting for anemia, neither serum ferritin nor NTBI impacted the HRV. However cardiac T2* was an independent predictor of HRV, even after adjusting for anemia. For receiver operative characteristic (ROC) curve analysis of cardiac T2* ≤20 ms, only mean ferritin in the last 12 months and the average of the standard deviation of all R-R intervals for all five-minute segments in the 24-hour recording were predictors for cardiac T2* ≤20 ms, with area under the ROC curve of 0.961 (p<0.0001) and 0.701 (p = 0.05), respectively.

Conclusions

Hemoglobin and cardiac T2* as significant predictors for HRV indicate that anemia and cardiac iron deposition result in cardiac autonomic imbalance. The mean ferritin in the last 12 months could be useful as the best indicator for further evaluation of cardiac risk. The ability of serum ferritin to predict cardiac risk is stronger than observed in other thalassemia cohorts. HRV might be a stronger predictor of cardiac iron in study populations with lower somatic iron burdens and greater prevalence of cardiac iron deposition.

Quality of life, clinical effectiveness, and satisfaction in patients with beta thalassemia major and sickle cell anemia receiving deferasirox chelation therapy

Objectives:

There is a need to remove excess iron with iron chelation therapy (ICT) to avoid the serious clinical sequelae associated with iron overload in patients with beta thalassemia major (BTM) and sickle cell anemia (SCA). Due to the effects of the diseases and their treatments, ICT is still a major reason for unsatisfactory compliance. The aim of this single-center observational study was to evaluate the quality of life, clinical effectiveness, and satisfaction in pediatric and adult patients with BTM and SCA receiving deferasirox (DFX) chelation therapy.

Methods:

In this study, 37 pediatric and 35 adult patients with BTM or SCA receiving DFX for at least 6 months participated. Upon receipt of Informed Consent Form, Case Report Form, Demographic Data Collection Form, Child Health Questionnaire-Parent Form, Life Quality Survey Short Form-36, and ICT Satisfaction Survey were used to obtain data for the effectiveness of ICT and parameters that may affect compliance to treatment and life quality of the participants.

Results:

As a main index for the effectiveness of DFX chelation therapy, serum ferritin levels were higher than the normal values in the patients receiving DFX. The increased ferritin levels were also associated with hematological and biochemical abnormalities. Our findings regarding quality of life and satisfaction with DFX chelation therapy indicated that the patients with BTM or SCA had lower scores. Overall, problems with treatment regimen and side effects appeared to be common causes of poor compliance to DFX chelation therapy.

Conclusions:

Our findings suggest that health care providers should be aware of the importance of monitoring iron load with timely initiation of DFX chelation therapy and ongoing adjustments to chelation regimens and/or transfusion methods to decrease hospitalizations and improve compliance to ICT of the patients with BTM and SCA.

New developments and controversies in iron metabolism and iron chelation therapy

Iron is essential for all organisms including microbial, cancer and human cells. More than a quarter of the human population is affected by abnormalities of iron metabolism, mainly from iron deficiency and iron overload. Iron also plays an important role in free radical pathology and oxidative damage which is observed in almost all major diseases, cancer and ageing. New developments include the complete treatment of iron overload and reduction of morbidity and mortality in thalassaemia using deferiprone and selected deferiprone/deferoxamine combinations and also the use of the maltol iron complex in the treatment of iron deficiency anaemia. There is also a prospect of using deferiprone as a universal antioxidant in non iron overloaded diseases such as neurodegenerative, cardiovascular, renal, infectious diseases and cancer. New regulatory molecules of iron metabolism such as endogenous and dietary chelating molecules, hepcidin, mitochondrial ferritin and their role in health and disease is under evaluation. Similarly, new mechanisms of iron deposition, removal, distribution and toxicity have been identified using new techniques such as magnetic resonance imaging increasing our understanding of iron metabolic processes and the targeted treatment of related diseases. The uniform distribution of iron in iron overload between organs and within each organ is no longer valid. Several other controversies such as the toxicity impact of non transferrin bound iron vs injected iron, the excess levels of iron in tissues causing toxicity and the role of chelation on iron absorption need further investigation. Commercial interests of pharmaceutical companies and connections to leading journals are playing a crucial role in shaping worldwide medical opinion on drug sales and use but also patients' therapeutic outcome and safety. Major controversies include the selection criteria and risk/benefit assessment in the use of deferasirox in thalassaemia and more so in idiopathic haemochromatosis, thalassaemia intermedia and ex-thalassaemia transplanted patients who are safely treated with venesection. Iron chelating drugs can override normal regulatory pathways, correct iron imbalance and minimise iron toxicity. The use of iron chelating drugs as main, alternative or adjuvant therapy is in progress in many conditions, especially those with non established or effective therapies.

Consequences of Delayed Prenatal Diagnosis of β-Thalassemia in Mainland China

β-Thalassemia (β-thal) is one of the most common inherited single gene disorders in the world. The aim of this study was to describe the gestational age at prenatal diagnosis (PND) for β-thal in at-risk women in mainland China. All pregnant women at-risk for β-thal and undergoing PND at a Mainland Chinese tertiary obstetric center between January 2005 and December 2014 were included. Information required for the survey was obtained from prenatal records and delivery charts. In total, 1307 women underwent PND for β-thal. The mean gestational age for the procedure was 18.5 weeks. There were 384 (29.0%) women with fetal diagnosis in early trimester (<14 weeks), 715 (55.0%) in early second trimester (14-24 weeks), and 208 (16.0%) in late second trimester or beyond (>24 weeks). Although the proportion of patients undergoing early PND increased along with the time span, the mean n gestational age was not decreased significantly during the study period. The delay in PND deprived couples of the opportunity to make informed decisions early in pregnancy.

TLc-A, the leading nanochelating-based nanochelator, reduces iron overload in vitro and in vivo

Iron chelation therapy is an effective approach to the treatment of iron overload conditions, in which iron builds up to toxic levels in the body and may cause organ damage. Treatments using deferoxamine, deferasirox and deferiprone have been introduced and despite their disadvantages, they remain the first-line therapeutics in iron chelation therapy. Our study aimed to compare the effectiveness of the iron chelation agent TLc-A, a nano chelator synthetized based on the novel nanochelating technology, with deferoxamine. We found that TLc-A reduced iron overload in Caco2 cell line more efficiently than deferoxamine. In rats with iron overload, very low concentrations of TLc-A lowered serum iron level after only three injections of the nanochelator, while deferoxamine was unable to reduce iron level after the same number of injections. Compared with deferoxamine, TLc-A significantly increased urinary iron excretion and reduced hepatic iron content. The toxicity study showed that the intraperitoneal median lethal dose for TLc-A was at least two times higher than that for deferoxamine. In conclusion, our in vitro and in vivo studies indicate that the novel nano chelator compound, TLc-A, offers superior performance in iron reduction than the commercially available and widely used deferoxamine.

Iron Chelation in Thalassemia Major

PURPOSE

Iron chelation has improved survival and quality of life of patients with thalassemia major. there are currently 3 commercially available iron-chelating drugs with different pharmacokinetic and pharmacodynamic activity. The choice of adequate chelation treatment should be tailored to patient needs and based on up-to-date scientific evidence.

METHODS

A review of the most recent literature was performed.

FINDINGS

The ability of the chelators to bind the redox active component of iron, labile plasma iron, is crucial for protecting the cells. Chelation therapy should be guided by magnetic resonance imaging that permits the tailoring of therapy according to the needs of the patient because different chelators preferentially clear iron from different sites. Normal levels of body iron seem to decrease the need for hormonal and cardiac therapy.

IMPLICATIONS

The 3 chelators currently available have different benefits, different safety profiles, and different acceptance on the part of the patients. Good-quality, well-designed, randomized, long-term clinical trials continue to be needed.

A complicated disease: what can be done to manage thalassemia major more effectively?

Patients with thalassemia major suffer from many complications, but in the last two decades their lives have improved both in length and quality. We report herein the most common complications and the recent advances that have changed the course of this disease. Also, we report in detail some of the new therapeutic strategies already introduced in practice and briefly some that are still being developed.

Iron chelation with deferasirox in a patient with de-novo ferroportin mutation

Ferroportin disease is a rare type of autosomal dominantly inherited hemochromatosis caused with mutations in the ferroportin gene (SLC40A1). The patients characteristically have hyperferritinemia but normal transferin saturations. Herein, we present a 15-year-old female whose chief complaint was persistent nausea for the last one year. Extensive work-up including brain imaging revealed nothing to explain the etiology of nausea. The serum ferritin level of 1474ng/mL was suggestive for hemochromatosis syndromes and the molecular testing revealed de-novo c.485_487delTTG (P.Val162del) ferroportin gene mutation. Mild hepatic iron loading, in addition to the cumbersome nausea were accepted as indications for chelation treatment in this particular patient and deferasirox was initiated (10mg/kg/day) since family did not consent for phlebotomy. Deferasirox was stopped by the 9th month of initiation, since nausea subsided and hepatic iron content was normalized, in order to prevent over chelation. There are no well-established guidelines for the chelation of patients with hereditary hemochromatosis syndromes. However, lifelong monitorization for iron loading and re-initiation of chelation when necessary was planned in our patient.

Deferasirox in a refractory anemia after other treatment options: case report and literature review

Deferasirox, represents an effective iron chelator drug in lower risk myelodysplastic syndromes. Reduction in oxidative stress is responsible of the hematologic improvement but further explanation may impact on its benefit. Biological and clinical studies are necessary to better define mechanisms of action, assess toxicities, and predicting factors of response.

Pleiotropic actions of iron balance in diabetes mellitus

As an essential element, iron plays a central role in many physiological processes, including redox balance, inflammation, energy metabolism, and environment sensing. Perturbations in iron homeostasis are associated with several conditions, including hyperglycemia and diabetes, both of which have been studied in patients and animal models. To clarify the pleiotropic role of iron homeostasis in diabetes development, the early studies on diseases with iron-overload, studies on clinical iron depletion therapies, associations between iron-related genetic polymorphisms and diabetes, and etiological mechanisms underlying iron perturbations-impaired insulin secretion and insulin sensitivity were carefully reviewed and discussed. Hereditary hemochromatosis, transfusion-dependent thalassemia, and excess heme iron intake can increase the risk of developing diabetes. Genetically modified mice and mice fed a high-iron diet present with discrepant phenotypes due to differences in tissue iron distribution. Moreover, several genetic polymorphisms related to iron homeostasis have been associated with the risk of developing diabetes. Tightly controlled iron metabolism is essential for insulin secretion and insulin sensitivity, and iron overload in pancreatic islets alters reactive oxygen species (ROS) generation, as well as hypoxia-inducible factor-1α (HIF-1α) stability and adenosine triphosphate (ATP) synthesis, thereby impairing the function and viability of β-cells. Decreased levels of adiponectin, macrophage-mediated inflammation, and ROS-mediated liver kinase B1 (LKB1)/adenosine monophosphate-activated protein kinase (AMPK) activation can contribute to iron overload-induced insulin resistance, whereas iron deficiency could also participate in obesity-related inflammation, hypoxia, and insulin resistance. Because iron homeostasis is closely correlated with many metabolic processes, future studies are needed in order to elucidate the finely tuned network among iron homeostasis, carbohydrate and lipid metabolism, inflammation, and hypoxia.