IL-6 signaling accelerates iron overload by upregulating DMT1 in endothelial cells to promote aortic dissection.

Aortic dissection (AD), caused by tearing of the intima and avulsion of the aortic media, is a severe threat to patient life and organ function. Iron is closely related to dissection formation and organ injury, but the mechanism of iron ion transport disorder in endothelial cells (ECs) remains unclear. We identified the characteristic EC of dissection with iron overload by single-cell RNA sequencing data. After intersecting iron homeostasis and differentially expressed genes, it was found that hypoxia-inducible factor-1α (HIF-1α) and divalent metal transporter 1 (DMT1) are key genes for iron ion disorder. Subsequently, IL-6R was identified as an essential reason for the JAK-STAT activation, a classical iron regulation pathway, through further intersection and validation. In in vivo and in vitro, both high IL-6 receptor expression and elevated IL-6 levels promote JAK1-STAT3 phosphorylation, leading to increased HIF-1α protein levels. Elevated HIF-1α binds explicitly to the 5'-UTR sequence of the DMT1 gene and transcriptionally promotes DMT1 expression, thereby increasing Fe2+ accumulation and endoplasmic reticulum stress (ERS). Blocking IL-6R and free iron with deferoxamine and tocilizumab significantly prolonged survival and reduced aortic and organ damage in dissection mice. A comparison of perioperative data between AD patients and others revealed that high free iron, IL-6, and ERS levels are characteristics of AD patients and are correlated with prognosis. In conclusion, activated IL-6/JAK1/STAT3 signaling axis up-regulates DMT1 expression by increasing HIF-1α, thereby increasing intracellular Fe2+ accumulation and tissue injury, which suggests a potential therapeutic target for AD.

The predicting formula and scoring system for cardiac iron overload for thalassaemia children: Study from a middle-income country.

Magnetic resonance imaging T2* screening is the gold standard for detecting cardiac iron overload in thalassemia, but its implementation in Indonesia is limited by the high costs. A predicting formula and scoring system based on low-cost investigations is needed. This cross-sectional study was conducted among thalassemia aged 6-18 years at Rumah Sakit Anak dan Bunda RSAB Harapan Kita Indonesia, during October 2017 to April 2019. All subjects were scheduled for clinical examination, laboratory tests, ECGs, echocardiography, tissue Doppler imaging, and MRIT2*. Multivariate logistic regression was used to identify the formula, simplifying to a scoring system, and risk classification for myocardial iron overload using odds ratio (OR) and 95% confidence interval (CI). Significance was set as p<0,05. We recruited 80 children, of those, 8 (10%) were classified as cardiac iron overload based on MRI T2* screening. Multivariate logistic regression showed determinant factors for cardiac iron overload were hemoglobin (95% CI:1.92-369.14), reticulocyte (95% CI:1.14-232.33), mitral deceleration time (DT) (95% CI:1.80-810.62,), and tricuspid regurgitation (TR Vmax) (95% CI:1.87-1942.56) with aOR of 26.65, 14.27, 38.22, and 60.27 respectively. The formula for cardiac iron overload was decided as 9.32 + 3.28 (Hb) + 2.9 (reticulocyte) + 3.64 (DT) + 4.1 (TR Vmax). A scoring system was defined by simplifying the formula of Hb ≤ 8.2 g/L, reticulocyte ≤0.33%, DT ≤ 114.5 cm/s, and TR Vmax ≥ 2.37 m/s were given a score of 1, while others were assigned 0. Total scores of 0 or 1, 2 and 3 or 4 were categorized as low, moderate, and high risk for iron cardiac overload. The cardiac iron overload formula was 9.32 + 3.28 (Hb) + 2.9 (reticulocyte) + 3.64 (DT) + 4.1 (TR Vmax). Variables of Hb ≤ 8.2 g/L, reticulocyte ≤0.33%, DT ≤ 114.5 cm/s, and TR Vmax ≥ 2.37 m/s were given a score of 1, while others were assigned 0. Total scores of 0 or 1, 2, and 3 or 4 were categorized as low, moderate, and high risk for iron cardiac overload.

Macrophage-derived extracellular vesicles represent a promising endogenous iron-chelating therapy for iron overload and cardiac injury in myocardial infarction.

BACKGROUND: Cardiac iron overload and ferroptosis greatly contribute to the poor prognosis of myocardial infarction (MI). Iron chelator is one of the most promising strategies for scavenging excessive iron and alleviating cardiac dysfunction post MI. However, various side effects of existing chemical iron chelators restrict their clinical application, which calls for a more viable and safer approach to protect against iron injury in ischemic hearts. RESULTS: In this study, we isolated macrophage-derived extracellular vesicles (EVs) and identified macrophage-derived EVs as a novel endogenous biological chelator for iron. The administration of macrophage-derived EVs effectively reduced iron overload in hypoxia-treated cardiomyocytes and hearts post MI. Moreover, the oxidative stress and ferroptosis induced by excessive iron were considerably suppressed by application of macrophage-derived EVs. Mechanistically, transferrin receptor (TfR), which was inherited from macrophage to the surface of EVs, endowed EVs with the ability to bind to transferrin and remove excess protein-bound iron. EVs with TfR deficiency exhibited a loss of function in preventing MI-induced iron overload and protecting the heart from MI injury. Furthermore, the iron-chelating EVs were ultimately captured and processed by macrophages in the liver. CONCLUSIONS: These results highlight the potential of macrophage-derived EVs as a powerful endogenous candidate for iron chelation therapy, offering a novel and promising therapeutic approach to protect against iron overload-induced injury in MI and other cardiovascular diseases.

Skin complications during iron chelation therapy for beta-thalassemia: overview and treatment approach.

Thalassemia is an inherited genetic disorder of hemoglobin that affects a large population worldwide, and it is estimated that between 50,000 and 60,000 infants with thalassemia are born each year. The most common treatment for thalassemia is blood transfusion, which leads to iron overload. This in itself is a serious clinical condition, and is commonly managed with iron chelation therapy. However, iron chelators can cause various skin complications, including hyperpigmentation, skin rash, itching, and photosensitivity. These skin side effects can impact patients' quality of life. Therefore, this article provides a comprehensive overview of skin complications caused by iron chelators, along with a proposed comprehensive approach to their management in patients with beta-thalassemia. Key strategies include patient education, regular skin assessment, sun protection measures, symptomatic relief with topical corticosteroids and antihistamines, and consideration of treatment modification if severe complications occur. Collaboration between hematologists and dermatologists, along with psychological support and regular follow-up, is an essential component of this multidisciplinary approach. By implementing these strategies, healthcare providers can optimize skin care for patients with beta-thalassemia treated with iron chelators and improve their quality of life.

Comorbidities and complications in adult and paediatric patients with pyruvate kinase deficiency: Analysis from the Peak Registry.

Pyruvate kinase (PK) deficiency, a rare, congenital haemolytic anaemia caused by mutations in the PKLR gene, is associated with many clinical manifestations, but the full disease burden has yet to be characterised. The Peak Registry (NCT03481738) is an observational, longitudinal registry of adult and paediatric patients with PK deficiency. Here, we described comorbidities and complications in these patients by age at most recent visit and PKLR genotype. As of 13 May 2022, 241 patients were included in the analysis. In total, 48.3% had undergone splenectomy and 50.5% had received chelation therapy. History of iron overload (before enrolment/during follow-up) was common (52.5%), even in never-transfused patients (20.7%). Neonatal complications and symptoms included jaundice, splenomegaly and hepatomegaly, with treatment interventions required in 41.5%. Among adults, osteopenia/osteoporosis occurred in 19.0% and pulmonary hypertension in 6.7%, with median onset ages of 37, 33 and 22 years, respectively. Biliary events and bone health problems were common across PKLR genotypes. Among 11 patients who had thromboembolic events, eight had undergone prior splenectomy. Patients with PK deficiency may have many complications, which can occur early in and throughout life. Awareness of their high disease burden may help clinicians better provide appropriate monitoring and management of these patients.

High ferritin is associated with liver and bone marrow iron accumulation: Effects of 1-year deferoxamine treatment in hemodialysis-associated iron overload.

BACKGROUND: Iron (Fe) supplementation is a critical component of anemia therapy for patients with chronic kidney disease (CKD). However, serum Fe, ferritin, and transferrin saturation, used to guide Fe replacement, are far from optimal, as they can be influenced by malnutrition and inflammation. Currently, there is a trend of increasing Fe supplementation to target high ferritin levels, although the long-term risk has been overlooked. METHODS: We prospectively enrolled 28 patients with CKD on hemodialysis with high serum ferritin (> 1000 ng/ml) and tested the effects of 1-year deferoxamine treatment, accompanied by withdrawal of Fe administration, on laboratory parameters (Fe status, inflammatory and CKD-MBD markers), heart, liver, and iliac crest Fe deposition (quantitative magnetic resonance imaging [MRI]), and bone biopsy (histomorphometry and counting of the number of Fe positive cells in the bone marrow). RESULTS: MRI parameters showed that none of the patients had heart iron overload, but they all presented iron overload in the liver and bone marrow, which was confirmed by bone histology. After therapy, ferritin levels decreased, although neither hemoglobin levels nor erythropoietin dose was changed. A significant decrease in hepcidin and FGF-23 levels was observed. Fe accumulation was improved in the liver and bone marrow, reaching normal values only in the bone marrow. No significant changes in turnover, mineralization or volume were observed. CONCLUSIONS: Our data suggest that treatment with deferoxamine was safe and could improve Fe accumulation, as measured by MRI and histomorphometry. Whether MRI is considered a standard tool for investigating bone marrow Fe accumulation requires further investigation. Registry and the registration number of clinical trial: ReBEC (Registro Brasileiro de Ensaios Clinicos) under the identification RBR-3rnskcj available at: https://ensaiosclinicos.gov.br/pesquisador.

Astragaloside IV attenuates ferroptosis and protects against iron overload-induced retinal injury.

Retinal injury may be exacerbated by iron overload. Astragaloside IV (AS-IV) has potential applications in the food and healthcare industry to promote eye health. We sought to determine the mechanisms responsible for the protective effects of AS-IV on photoreceptor and retinal pigment epithelium cell death induced by iron overload. We conducted in vitro and in vivo experiments involving AS-IV pretreatment. We tested AS-IV for its ability to protect iron-overload mice from retinal injury. In particular, we analyzed the effects of AS-IV on iron overload-induced ferroptosis in 661W and ARPE-19 cells. AS-IV not only attenuated iron deposition and retinal injury in iron-overload mice but also effectively reduced iron overload-induced ferroptotic cell death in 661W and ARPE-19 cells. AS-IV effectively prevented ferroptosis by inhibiting iron accumulation and lipid peroxidation. In addition, inhibiting nuclear factor erythroid 2-related factor 2 (Nrf2) eliminated the protective effect of AS-IV against ferroptosis. The results suggest that ferroptosis might be a significant cause of retinal cell death associated with iron overload. AS-IV provides protection from iron overload-induced ferroptosis, partly by activating the Nrf2 signaling pathway.

Transfusional hemosiderosis in childhood cancer patients and survivors.

BACKGROUND: Children treated for cancer are at risk for adverse effects of iron due to transfusions administered during prolonged marrow suppression, which may increase exposure to toxic forms of iron, extrahepatic iron accumulation, and long-term organ damage. OBJECTIVE: This study aimed to characterize the severity and organ distribution of clinically significant, multisystem iron overload (IO) in an at-risk cohort of pediatric cancer patients. METHODS: This was a retrospective, cross-sectional study of childhood cancer patients who underwent a magnetic resonance imaging (MRI) due to clinical concern for IO. Data regarding cancer type and treatment, transfusion history, MRI and laboratory results, and treatment for IO were collected. Severity of IO was analyzed by non-parametric tests with respect to clinical characteristics. RESULTS: Of the 103 patients, 98% of whom had a Cancer Intensity Treatment Rating (ITR-3) of 3 or higher, 53% (54/102) had moderate or greater hepatic siderosis, 80% (77/96) had pancreatic siderosis, 4% (3/80) had cardiac siderosis, and 45% (13/29) had pituitary siderosis and/or volume loss. Pancreatic iron was associated with both cardiac (p = .0043) and pituitary iron (p = .0101). In the 73 off-therapy patients, ferritin levels were lower (p = .0008) with higher correlation with liver iron concentration (LIC) (p = .0016) than on-therapy patients. Fifty-eight subjects were treated for IO. CONCLUSION: In this heavily treated cohort of pediatric cancer patients, more than 80% had extrahepatic iron loading, which occurs with significant exposure to toxic forms of iron related to decreased marrow activity in setting of transfusions. Further studies should examine the effects of exposure to reactive iron on long-term outcomes and potential strategies for management.

Protocatechualdehyde inhibits iron overload-induced bone loss by inhibiting inflammation and oxidative stress in senile rats.

The accumulating evidence has made it clear that iron overload is a crucial mechanism in bone loss. Protocatechualdehyde (PCA) has also been used to prevent osteoporosis in recent years. Whether PCA can reverse the harmful effects of iron overload on bone mass in aged rats is still unknown. Therefore, this study aimed to assess the role of PCA in iron overload-induced bone loss in senile rats. In the aged rat model, we observed that iron overload affects bone metabolism and bone remodeling, manifested by bone loss and decreased bone mineral density. The administration of PCA effectively mitigated the detrimental effects caused by iron overload, and concomitant reduction in MDA serum levels and elevation of SOD were noted. In addition, PCA-treated rats were observed to have significantly increased bone mass and elevated expression of SIRT3，BMP2，SOD2 and reduced expression of TNF-α in bone tissue. We also observed that PCA was able to reduce oxidative stress and inflammation and restore the imbalance in bone metabolism. When MC3T3-E1 and RAW264.7 cells induced osteoblast and osteoclasts differentiation, PCA intervention could significantly recover the restriction of osteogenic differentiation and up-regulation of osteoclast differentiation treated by iron overload. Further, by detecting changes in ROS, SOD, MDA, expression of SIRT3 and mitochondrial membrane potentials, we confirm that the damage caused to cells by iron overload is associated with decreased SIRT3 activity, and that 3-TYP have similar effects on oxidative stress caused by FAC. In conclusion, PCA can resist iron overload-induced bone damage by improving SIRT3 activity, anti-inflammatory and anti-oxidative stress.

Association of serum iron metabolism with muscle mass and frailty in older adults: A cross-sectional study of community-dwelling older adults.

This study aimed to explore the correlation between serum ferritin and additional biomarkers associated with iron metabolism, as well as their connection to muscle atrophy and frailty in the community-dwelling middle-aged and elderly population. The study included 110 middle-aged and elderly participants. Participants were categorized into an iron accumulation group (31 cases) and a normal iron group (79 cases) based on the standard ferritin values for men and women. Based on the criteria of the Asian Working Group on Muscular Dystrophy, participants were classified into a sarcopenia group (31 cases) and a non-sarcopenia group (79 cases). Using the Fried frailty syndrome criteria, participants were categorized into non-frailty (7 cases), pre-frailty (50 cases), and frailty (53 cases) groups. We employed multiple linear regression, binary logistic regression, partial correlation analysis, and ordinal logistic regression to assess the associations between iron metabolism indices and the presence of muscle atrophy and frailty. Compared with the normal iron group, the iron overload group had significantly higher ferritin, weight loss, fatigue, slow gait, and frailty scores (P < .05). Among the 3 models we set, ferritin was not significantly correlated with muscle mass in models 1 and 3 (P > .05), ferritin was positively correlated with muscle mass in model 2 (Pmodel2 = .048), but Transferrin saturation was positively correlated with muscle mass in all 3 models (Pmodel1 = .047, Pmodel2 = .026, Pmodel3 = .024). Ferritin, body mass index and iron overload were the influencing factors of sarcopenia (Pferritin = .027, PBMI < .001, Piron overload = .028). Ferritin was positively correlated with weight loss, fatigue, slow gait, frailty score, and frailty grade (P < .05). Age, gender and ferritin were the influencing factors of frailty classification (P < .05). Disrupted iron metabolism can lead to decreased muscle mass and function among the middle-aged and elderly, increasing frailty risk. It's crucial to prioritize community-based frailty screening and prevention, focusing on iron utilization as well as storage, since accelerating the body's iron metabolism cycle might influence muscle health more significantly than iron reserves.

Impact of Serum Ferritin and Iron Overload on Acute Myeloid Leukemia Outcomes: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the iron overload among individuals with acute myeloid leukemia (AML) who have not received red blood cell transfusions. METHODS: A comprehensive search was conducted in Embase, PubMed, PubMed Central, Web of Science, NIH, and Blood Library databases up to September 2023. The search strategy included keywords related to AML, iron overload, serum ferritin, survival, outcomes, and inflammation. Manual searches through included articles and relevant references were also performed. From 1650 initial articles, 16 studies involving 8752 patients met the inclusion criteria for systematic review. Statistical analysis used hazard ratios (HR) and confidence intervals (CI).  Results: The systematic review and meta-analysis revealed a statistically significant association between high serum ferritin (SF) levels and poor outcomes in AML patients before starting chemotherapy. Elevated SF levels (>1000 mg/L) were associated with lower overall survival (OS) and event-free survival (EFS) (HR for OS: 1.99, 95% CI: 1.48-2.66; HR for EFS: 2.29, 95% CI: 1.73-3.05). Elevated SF levels were inversely correlated with the gradual onset of infections, indicating an increased risk of early mortality (p<0.05). CONCLUSION: Elevated serum ferritin levels are significantly associated with poor outcomes in AML patients before treatment initiation. These findings highlight the importance of monitoring iron levels in these patients to improve prognostic assessments and treatment strategies.

[Clinical analysis on the impact of pretransplant iron overload on allogeneic hematopoietic stem cell transplantation for patients with acquired severe aplastic anemia in pediatric].

This study aimed to investigate the effect of iron overload on the transplant outcomes of pediatric patients with severe aplastic anemia (SAA) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). A retrospective analysis was conducted on the clinical data of 74 children with SAA who received allo-HSCT at the Hematology Department of Wuhan Children's Hospital between January 2018 and August 2022. Children with iron overload (serum ferritin >1 000 µg/L) before transplantation had a longer disease course, received more red blood cell transfusions, and had a higher number of CD34(+) cells infused. Moreover, iron overload significantly delayed the reconstitution of regulatory T cells after transplantation, increasing the incidence of hemorrhagic cystitis and grade Ⅲ-Ⅳ acute graft-versus-host disease after transplantation. However, iron overload did not significantly affect the overall survival and failure-free survival rates of the children.

Myelin endocytosis by brain endothelial cells causes endothelial iron overload and oligodendroglial iron hunger in hypoperfusion-induced white matter injury.

AIMS: Hypoperfusion induces significant white matter injury in cerebral vascular disorders, including arteriosclerotic cerebral small vessel disease (aCSVD), which is prevalent among the elderly. Iron transport by blood vessel endothelial cells (BVECs) from the periphery supports oligodendrocyte maturation and white matter repair. This study aims to elucidate the association between iron homeostasis changes and white matter injury severity, and explore the crosstalk between BVECs and oligodendroglial lineage cells. METHODS: In vivo: C57BL/6 mice were subjected to unilateral common carotid artery occlusion (UCCAO). In vitro: BVECs with myelin pretreatment were co-cultured with oligodendrocyte progenitor cells (OPCs) or organotypic cerebellar slices subjected to oxygen and glucose deprivation. RESULTS: Circulatory iron tends to be stored in aCSVD patients with white matter injury. Myelin debris endocytosis by BVECs impairs iron transport, trapping iron in the blood and away from the brain, worsening oligodendrocyte iron deficiency in hypoperfusion-induced white matter injury. Iron accumulation in BVECs triggers ferroptosis, suppressing iron transport and hindering white matter regeneration. Intranasal holo-transferrin (hTF) administration bypassing the BBB alleviates oligodendrocyte iron deficiency and promotes myelin regeneration in hypoperfusion-induced white matter injury. CONCLUSION: The iron imbalance between BVECs and oligodendroglial lineage cells is a potential therapeutic target in hypoperfusion-induced white matter injury.

The relationship between liver stiffness by two-dimensional shear wave elastography and iron overload status in transfusion-dependent patients.

Increased liver stiffness (LS) can be result of increased liver iron concentration (LIC) which may not yet be reflected in the liver fibrotic status. The objective of our study was to examine relationship between hemochromatosis, LS, and serum ferritin level in transfusion-dependent patients. We recruited all 70 transfusion-dependent patients, whose median age was 15, referred for evaluating LIC status by magnetic resonance imaging (MRI) followed by two-dimensional ultrasonography shear wave elastography (2D-SWE). Thalassemia beta affected the majority of the patients. The optimal cut point for prediction of severe hemochromatosis using median SWE (kPa) and SWV (m/s) was ≥ 7.0 kPa and ≥ 1.54 m/s, respectively, with sensitivity of 0.76 (95% confidence interval [CI] 0.55, 0.91) and, specificity of 0.69 (95%CI 0.53, 0.82). When combing the optimal cut point of SWE (kPa) at ≥ 7.0 and serum ferritin ≥ 4123 ng/mL, the sensitivity increased to 0.84 (95%CI 0.64, 0.95) with specificity of 0.67 (95%CI 0.50, 0.80), positive predictive value (PPV) of 0.60 (95%CI 0.42, 0.76), and negative predictive value (NPV) of 0.88 (95%CI 0.71, 0.96). Simultaneous tests of 2D-SWE and serum ferritin for prediction of severe hemochromatosis showed the highest sensitivity of 84% (95%CI 0.64-0.95), as compared to 2D-SWE alone at 76% (95%CI 0.55, 0.91) or serum ferritin alone at 44% (95%CI 0.24-0.65). We recommend measuring both 2D-SWE and serum ferritin in short interval follow up patients. Adding 2D-SWE to management guideline will help in deciding for aggressive adjustment of iron chelating medication and increased awareness of patients having severe hemochromatosis.

Correlation between plasma biochemical parameters and cardio-hepatic iron deposition in thalassemia major patients.

INTRODUCTION: Major Thalassemia patients suffer from iron overload and organ damage, especially heart and liver damage. Early diagnosis and treatment with a chelator can reduce the complications and mortality of iron overload. Therefore, we aimed to investigate the biochemical and hematological predictors as an alternative and indirect indicator of iron deposition in heart and liver cells in comparison with the MRI T2* method as the gold standard. MATERIAL AND METHOD: MRI T2* was evaluated in the heart and liver tissues of 62 major beta-thalassemia patients undergoing regular transfusion and chelator therapy. Biochemical and hematological factors were also measured, including serum ferritin, serum electrolytes, liver enzymes, hemoglobin, blood glucose, and serum magnesium. The correlation between these factors was assessed using statistical evaluations. RESULT: Serum ferritin had a positive and significant correlation with liver siderosis based on MRI T2* (p-value = .015), and no significant association was observed with cardiac siderosis (p-value = .79). However, there was a significant positive correlation between cardiac iron deposition and fasting blood sugar level (p-value = -.049), and plasma level of liver enzymes (alanine aminotransferase (ALT) (p-value = .001), aspartate aminotransferase (AST ((p-value = .01)). Moreover, there was a significant negative correlation between cardiac iron overload and plasma magnesium level (p-value = .014). According to MRI T2*, there was no significant correlation between cardiac and hepatic iron overload (p value = .36). CONCLUSION: An increase in blood sugar or liver enzymes and a decrease in serum magnesium was associated with an increase in cardiac iron overload based on MRI T2*. Liver iron overload based on MRI T2* had a significant correlation with serum ferritin.

Anemia and iron overload as prognostic markers of outcomes in ß-thalassemia.

INTRODUCTION: Ineffective erythropoiesis and subsequent anemia as well as primary and secondary (transfusional) iron overload are key drivers for morbidity and mortality outcomes in patients with ß-thalassemia. AREAS COVERED: In this review, we highlight evidence from observational studies evaluating the association between measures of anemia and iron overload versus outcomes in both non-transfusion-dependent and transfusion-dependent forms of ß-thalassemia. EXPERT OPINION: Several prognostic thresholds have been identified with implications for patient management. These have also formed the basis for the design of novel therapy clinical trials by informing eligibility and target endpoints. Still, several data gaps persist in view of the challenge of assessing prospective long-term outcomes in a chronic disease. Pooling insights on the prognostic value of different measures of disease mechanism will be key to design future scoring systems that can help optimize patient management.

Iron Chelators and Alzheimer's Disease Clinical Trials.

Alzheimer's disease (AD) is a major neurodegenerative disorder impacting millions of people with cognitive impairment and affecting activities of daily living. The deposition of neurofibrillary tangles of hyperphosphorylated tau proteins and accumulation of amyloid-ß (Aß) are the main pathological characteristics of AD. However, the actual causal process of AD is not yet identified. Oxidative stress occurs prior to amyloid Aß plaque formation and tau phosphorylation in AD. The role of master antioxidant, glutathione, and metal ions (e.g., iron) in AD are the frontline area of AD research. Iron overload in specific brain regions in AD is associated with the rate of cognitive decline. We have presented the outcome from various interventional trials involving iron chelators intended to minimize the iron overload in AD. To date, however, no significant positive outcomes have been reported using iron chelators in AD and warrant further research.

Comparison of R2* and FerriScan liver iron concentration (LIC) quantification in the clinical classification of Iron overload states.

PURPOSE: This study assessed the clinical classification performance of an R2*-based MRI technique for LIC quantification relative to FerriScan, with intra-patient FerriScan LIC uncertainty taken into account. The variabilities of R2* and FerriScan LIC were also assessed. MATERIALS AND METHODS: This was an ethics approved retrospective study, performed on patients undergoing chelation treatment for iron overload. 126 patients (69 women, 57 men), with an age of 42 +/- 16 years (range 19-86 years) were included. FerriScan and R2* MRI at 1.5 T were performed as part of a routine liver iron assessment protocol. For R2* MRI, a commercially available pulse sequence and reconstruction implementation was used, together with a previously derived calibration curve to convert R2* to LIC. Clinical classifications arising from R2*-derived LIC estimates were compared to those based on FerriScan. The accuracy and precision of the R2* technique was calculated. The variabilities of FerriScan- and R2*-derived estimates of LIC were compared with a Wilcoxon Signed Rank test. Significance was set at the 95% confidence level. RESULTS: The precision of R2* ranged from 0.59 to 0.92, with an overall accuracy of 72%. When intra-patient FerriScan LIC uncertainty was considered, precision and accuracy increased to >94% and 97% respectively. The R2*-LIC variability (=17%) was significantly lower than the FerriScan-LIC variability (34%) at the 95% confidence level (p < 10-3). CONCLUSION: MRI R2*-based LIC estimates provided a similar clinical classification as FerriScan. The intra-patient uncertainty of R2*-based LIC estimates was significantly lower than FerriScan.