Haemochromatosis

SUGP2 p.(Arg639Gln) variant is involved in the pathogenesis of hemochromatosis via the CIRBP/BMPER signaling pathway

Pathogenic variants in HFE and non-HFE genes have been identified in hemochromatosis in different patient populations, but there are still a certain number of patients with unexplained primary iron overload. We recently identified in Chinese patients a recurrent p.(Arg639Gln) variant in SURP and G-patch domain containing 2 (SUGP2), a potential mRNA splicing-related factor. However, the target gene of SUGP2 and affected iron-regulating pathway remains unknown. We aimed to investigate the pathogenicity and underlying mechanism of this variant in hemochromatosis. RNA-seq analysis revealed that SUGP2 knockdown caused abnormal alternative splicing of CIRBP pre-mRNA, resulting in an increased normal splicing form of CIRBP V1, which in turn increased the expression of BMPER by enhancing its mRNA stability and translation. Furthermore, RNA-protein pull-down and RNA immunoprecipitation assays revealed that SUGP2 inhibited splicing of CIRBP pre-mRNA by a splice site variant at CIRBP c.492 and was more susceptible to CIRBP c.492 C/C genotype. Cells transfected with SUGP2 p.(Arg639Gln) vector showed up-regulation of CIRBP V1 and BMPER expression and down-regulation of pSMAD1/5 and HAMP expression. CRISPR-Cas9 mediated SUGP2 p.(Arg622Gln) knock-in mice showed increased iron accumulation in the liver, higher total serum iron, and decreased serum hepcidin level. A total of 10 of 54 patients with hemochromatosis (18.5%) harbored the SUGP2 p.(Arg639Gln) variant and carried CIRBP c.492 C/C genotype, and had increased BMPER expression in the liver. Altogether, the SUGP2 p.(Arg639Gln) variant down-regulates hepcidin expression through the SUGP2/CIRBP/BMPER axis, which may represent a novel pathogenic factor for hemochromatosis.

Social defeat stress impairs systemic iron metabolism by activating the hepcidin-ferroportin axis

Chronic psychological stress has been reported to decrease circulating iron concentrations and impair hematopoiesis. However, the underlying mechanisms remain unclear. This study aimed to investigate the effects of psychological stress on biological iron metabolism by using the social defeat stress (SDS) model, a widely used model of depression. Compared with control mice, mice subjected to SDS (SDS mice) had lower social interaction (SI) behavior. The SDS mice also showed impaired hematopoiesis, as evidenced by reduced circulating red blood cell counts, elevated reticulocyte counts, and decreased plasma iron levels. In the SDS mice, the iron contents in the bone marrow decreased, whereas those in the spleen increased, suggesting dysregulation in systemic iron metabolism. The concentrations of plasma hepcidin, an important regulator of systemic iron homeostasis, increased in the SDS mice. Meanwhile, the concentrations of ferroportin, an iron transport protein negatively regulated by hepcidin, were lower in the spleen and duodenum of the SDS mice than in those of the control mice. Treatment with dalteparin, a hepcidin inhibitor, prevented the decrease in plasma iron levels in the SDS mice. The gene expression and enzyme activity of furin, which converts the precursor hepcidin to active hepcidin, were high and positively correlated with plasma hepcidin concentration. Thus, furin activation might be responsible for the increased plasma hepcidin concentration. This study is the first to show that psychological stress disrupts systemic iron homeostasis by activating the hepcidin-ferroportin axis. Consideration of psychological stressors might be beneficial in the treatment of diseases with iron-refractory anemia.

High Glucose Increases Lactate and Induces the Transforming Growth Factor Beta-Smad 1/5 Atherogenic Pathway in Primary Human Macrophages

Hundreds of millions of people worldwide are expected to suffer from diabetes mellitus. Diabetes is characterized as a dynamic and heterogeneous disease that requires deeper understanding of the pathophysiology, genetics, and metabolic shaping of this disease and its macro/microvascular complications. Macrophages play an essential role in regulating local immune responses, tissue homeostasis, and disease pathogenesis. Here, we have analyzed transforming growth factor beta 1 (TGFβ1)/Smad signaling in primary human macrophages grown in normal (NG) and high-glucose (HG; +25 mM glucose) conditions. Cell culture lactate concentration and cellular phosphofructokinase (PFK) activity were increased in HG concentrations. High glucose levels in the growth media led to increased macrophage mRNA expression of TGFβ1, and TGFβ-regulated HAMP and PLAUR mRNA levels, while the expression of TGFβ receptor II remained unchanged. Stimulation of cells with TGFβ1 protein lead to Smad2 phosphorylation in both NG and HG conditions, while the phosphorylation of Smad1/5 was detected only in response to TGFβ1 stimulation in HG conditions. The use of the specific Alk1/2 inhibitor dorsomorphin and the Alk5 inhibitor SB431542, respectively, revealed that HG conditions led TGFβ1 to activation of Smad1/5 signaling and its downstream target genes. Thus, high-glucose activates TGFβ1 signaling to the Smad1/5 pathway in primary human macrophages, which may contribute to cellular homeostasis in a harmful manner, priming the tissues for diabetic complications.

SLC40A1 in iron metabolism, ferroptosis, and disease: A review

Solute carrier family 40 member 1 (SLC40A1) plays an essential role in transporting iron from intracellular to extracellular environments. When SLC40A1 expression is abnormal, cellular iron metabolism becomes dysregulated, resulting in an overload of intracellular iron, which induces cell ferroptosis. Numerous studies have confirmed that ferroptosis is closely associated with the development of many diseases. Here, we review recent findings on SLC40A1 in ferroptosis and its association with various diseases, intending to explore new directions for research on disease pathogenesis and new therapeutic targets for prevention and treatment. This article is categorized under: Cancer > Genetics/Genomics/Epigenetics Metabolic Diseases > Molecular and Cellular Physiology.

Effects of dietary iron deficiency or overload on bone: Dietary details matter

PURPOSE

Bone is susceptible to fluctuations in iron homeostasis, as both iron deficiency and overload are linked to poor bone strength in humans. In mice, however, inconsistent results have been reported, likely due to different diet setups or genetic backgrounds. Here, we assessed the effect of different high and low iron diets on bone in six inbred mouse strains (C57BL/6J, A/J, BALB/cJ, AKR/J, C3H/HeJ, and DBA/2J).

METHODS

Mice received a high (20,000 ppm) or low-iron diet (∼10 ppm) after weaning for 6-8 weeks. For C57BL/6J males, we used two dietary setups with similar amounts of iron, yet different nutritional compositions that were either richer ("TUD study") or poorer ("UCLA study") in minerals and vitamins. After sacrifice, liver, blood and bone parameters as well as bone turnover markers in the serum were analyzed.

RESULTS

Almost all mice on the UCLA study high iron diet had a significant decrease of cortical and trabecular bone mass accompanied by high bone resorption. Iron deficiency did not change bone microarchitecture or turnover in C57BL/6J, A/J, and DBA/2J mice, but increased trabecular bone mass in BALB/cJ, C3H/HeJ and AKR/J mice. In contrast to the UCLA study, male C57BL/6J mice in the TUD study did not display any changes in trabecular bone mass or turnover on high or low iron diet. However, cortical bone parameters were also decreased in TUD mice on the high iron diet.

CONCLUSION

Thus, these data show that cortical bone is more susceptible to iron overload than trabecular bone and highlight the importance of a nutrient-rich diet to potentially mitigate the negative effects of iron overload on bone.

Hemochromatosis-How Not to Overlook and Properly Manage "Iron People"-A Review

Hemochromatosis (HC) is the main genetic disorder of iron overload and is regarded as metal-related human toxicosis. HC may result from HFE and rare non-HFE gene mutations, causing hepcidin deficiency or, sporadically, hepcidin resistance. This review focuses on HFE-related HC. The illness presents a strong biochemical penetrance, but its prevalence is low. Unfortunately, the majority of patients with HC remain undiagnosed at their disease-curable stage. The main aim of HC management is to prevent iron overload in its early phase and remove excess iron from the body by phlebotomy in its late stage. Raising global awareness of HC among health staff, teaching them how not to overlook early HC manifestations, and paying attention to careful patient monitoring remain critical management strategies for preventing treatment delays, upgrading its efficacy, and improving patient prognosis.

SLC40A1-related hemochromatosis associated with a p.Y333H mutation in mainland China: a pedigree report and literature review

BACKGROUND

Haemochromatosis is a genetic disease characterized by the excessive deposition of iron in various tissues and organs, eventually results in organ damage including cirrhosis, diabetes, cardiomyopathy, etc. SLC40A1-related haemochromatosis is associated with gain-of-function mutations in the SLC40A1 gene, which encodes ferroportin. While sporadic reports of this condition exist in mainland China, the understanding of the phenotype and genetic pattern associated with the SLC40A1 p.Y333H mutation remains incomplete.

CASE PRESENTATION

We report a pedigree with heterozygous p.Y333H mutation in Chinese Han population. The proband is a 64-year-old man complaining of persistent abnormality of liver enzyme levels for 1 year, with a history of knee joint pain, diabetes and skin pigmentation. He displayed markedly elevated serum ferritin level and transferrin saturation. Magnetic resonance imaging showed iron deposition in the liver, spleen, and pancreas, along with cirrhosis and splenomegaly. Whole exome sequencing identified a heterozygous allelic variant c.997T > C (p.Y333H). Genetic screening of family members identified four first-degree relatives and three second-degree relatives having the same mutation. Additional cases with this mutation from two published studies were included. Among the probands and screened relatives, all eight males aged over 30 y had ferritin level > 1000 µg/L, transferrin saturation > 90%. Four patients with organ damage in the present study received therapeutic phlebotomy, alleviating clinical symptoms and improving in transferrin saturation and serum ferritin.

CONCLUSIONS

This study reports the largest pedigree with heterozygous SLC40A1 p.Y333H mutation in the Chinese population to date. In Chinese families, males over 30 years old with hemochromatosis due to SLC40A1 p.Y333H mutation exhibit severe iron overload phenotypes.

Research advances on molecular mechanism and natural product therapy of iron metabolism in heart failure

The progression of heart failure (HF) is complex and involves multiple regulatory pathways. Iron ions play a crucial supportive role as a cofactor for important proteins such as hemoglobin, myoglobin, oxidative respiratory chain, and DNA synthetase, in the myocardial energy metabolism process. In recent years, numerous studies have shown that HF is associated with iron dysmetabolism, and deficiencies in iron and overload of iron can both lead to the development of various myocarditis diseases, which ultimately progress to HF. Iron toxicity and iron metabolism may be key targets for the diagnosis, treatment, and prevention of HF. Some iron chelators (such as desferrioxamine), antioxidants (such as ascorbate), Fer-1, and molecules that regulate iron levels (such as lactoferrin) have been shown to be effective in treating HF and protecting the myocardium in multiple studies. Additionally, certain natural compounds can play a significant role by mediating the imbalance of iron-related signaling pathways and expression levels. Therefore, this review not only summarizes the basic processes of iron metabolism in the body and the mechanisms by which they play a role in HF, with the aim of providing new clues and considerations for the treatment of HF, but also summarizes recent studies on natural chemical components that involve ferroptosis and its role in HF pathology, as well as the mechanisms by which naturally occurring products regulate ferroptosis in HF, with the aim of providing reference information for the development of new ferroptosis inhibitors and lead compounds for the treatment of HF in the future.

Iron Absorption: Molecular and Pathophysiological Aspects

Iron is an essential nutrient for growth among all branches of life, but while iron is among the most common elements, bioavailable iron is a relatively scarce nutrient. Since iron is fundamental for several biological processes, iron deficiency can be deleterious. On the other hand, excess iron may lead to cell and tissue damage. Consequently, iron balance is strictly regulated. As iron excretion is not physiologically controlled, systemic iron homeostasis is maintained at the level of absorption, which is mainly influenced by the amount of iron stores and the level of erythropoietic activity, the major iron consumer. Here, we outline recent advances that increased our understanding of the molecular aspects of iron absorption. Moreover, we examine the impact of these recent insights on dietary strategies for maintaining iron balance.

A genome-wide association study provides insights into the genetic etiology of 57 essential and non-essential trace elements in humans

Trace elements are important for human health but may exert toxic or adverse effects. Mechanisms of uptake, distribution, metabolism, and excretion are partly under genetic control but have not yet been extensively mapped. Here we report a comprehensive multi-element genome-wide association study of 57 essential and non-essential trace elements. We perform genome-wide association meta-analyses of 14 trace elements in up to 6564 Scandinavian whole blood samples, and genome-wide association studies of 43 trace elements in up to 2819 samples measured only in the Trøndelag Health Study (HUNT). We identify 11 novel genetic loci associated with blood concentrations of arsenic, cadmium, manganese, selenium, and zinc in genome-wide association meta-analyses. In HUNT, several genome-wide significant loci are also indicated for other trace elements. Using two-sample Mendelian randomization, we find several indications of weak to moderate effects on health outcomes, the most precise being a weak harmful effect of increased zinc on prostate cancer. However, independent validation is needed. Our current understanding of trace element-associated genetic variants may help establish consequences of trace elements on human health.

B-1 derived anti-Thy-1 B cells in old aged mice develop lymphoma/leukemia with high expression of CD11b and Hamp2 that different from TCL1 transgenic mice

Human old aged unmutated chronic lymphocytic leukemia U-CLL are the TCL1+ZAP70+CD5+ B cells. Since CD5 makes the BCR signaling tolerance, ZAP70 increased in U-CLL not only TCL1+ alone. In mice, TCL1 (TCL1A) is the negative from neonate to old aged, as TC-. VH8-12/Vk21-5 is the anti-thymocyte/Thy-1 autoreactive ATA B cell. When ATA μκTg generation in mice, ATA B cells are the neonate generated CD5+ B cells in B-1, and in the middle age, CD5+ can be down or continuously CD5+, then, old aged CLL/lymphoma generation with increased CD11b in TC-ZAP70-CD5- or TC-ZAP70+CD5+. In this old aged TC-ATA B microarray analysis showed most similar to human CLL and U-CLL, and TC-ZAP70+CD5+ showed certain higher present as U-CLL. Original neonate ATA B cells showed with several genes down or further increase in old aged tumor, and old aged T-bet+CD11c+, CTNNB1hi, HMGBhi, CXCR4hi, DPP4hi and decreased miR181b. These old aged increased genes and down miR181b are similar to human CLL. Also, in old age ATA B cell tumor, high CD38++CD44++, increased Ki67+ AID+, and decreased CD180- miR15Olow are similar to U-CLL. In this old aged ATA B, increased TLR7,9 and Wnt10b. TC+Tg generated with ATAμκTg mice occurred middle age tumor as TC+ZAP70-CD5+ or TC+ZAP70+CD5+, with high NF-kB1, TLR4,6 and Wnt5b,6 without increased CD11b. Since neonatal state to age with TC+Tg continuously, middle age CLL/lymphoma generation is not similar to old aged generated, however, some increased in TC+ZAP70+ are similar to the old age TC- ATA B tumor. Then, TC- ATA B old age tumor showed some difference to human CLL. ATA B cells showed CD11b+CD22++, CD24 down, and hepcidin Hamp2++ with iron down. This mouse V8-12 similar to human V2-5, and V2-5 showed several cancers with macrophages/neutrophils generated hepcidin+ ironlow or some showed hepcidin- iron+ with tumor, and mouse V8-12 with different Vk19-17 generate MZ B cells strongly increased macrophage++ in old aged and generated intestine/colon tumor. Conclusion, neonate generated TC-ATA B1 cells in old aged tumor generation are CD11b+ in the leukemia CLL together with lymphoma cancer with hepcidin-related Hamp2++ in B-1 cell generation to control iron.

Calcified Thoracic Disc - A descriptive classification with clinical and management implications

Introduction and Objective

Thoracic disc calcification is a radiological finding which may be incidental or diagnosed in patients presenting with myelopathy due to spinal cord compression. We performed a study to analyze the imaging patterns of calcified thoracic discs (CTDs).

Patients and Methods

A retrospective review of the spinal and radiology database of a tertiary referral orthopedic hospital was conducted for the incidence of CTDs between 2007 and 2020. Patients' demographics and radiological findings were recorded. The relationship between disc size, morphology, spinal cord compression, and management was assessed.

Results

Fifty-one cases of CTDs were identified. The mean size of CTD was 806.2 mm3 (range: 144-2340). The most common level of disc calcification was T9-T10 (24%) in 12 patients. Thoracic disc calcifications in our series commonly involved disc "protrusion" in 67% (34 patients), followed by "mushroom" type in 31% (16 patients) and "extrusion" in 2% (1 patient). 37% (19 patients) had spinal cord compression with 12% (6 patients) undergoing surgical interventions. There was no statistically significant difference in the mean sizes of CTD between the groups with and without spinal cord compression (P = 0.566, independent sample t-test). Patients with "mushroom" type calcification were more likely to have surgical intervention (P = 0.01, Fisher's exact test).

Conclusion

Thoracic disc calcifications, while common, can still be underdiagnosed till late myelopathic deterioration. Care of the elderly physicians, spinal surgeons, and radiologists need to be aware of them to guide diagnosis and management. Our study demonstrates that disc morphology plays a vital role in myelopathic presentation and therefore determines the need for surgical intervention instead of the absolute size of disc calcification.

Penetrance, cancer incidence and survival in HFE haemochromatosis-A population-based cohort study

BACKGROUND AND AIMS

Haemochromatosis is characterized by progressive iron overload affecting the liver and can cause cirrhosis and hepatocellular carcinoma. Most haemochromatosis patients are homozygous for p.C282Y in HFE, but only a minority of individuals with this genotype will develop the disease. The aim was to assess the penetrance of iron overload, fibrosis, hepatocellular carcinoma and life expectancy.

METHODS

A total of 8839 individuals from the Austrian region of Tyrol were genotyped for the p.C282Y variant between 1997 and 2021. Demographic, laboratory parameters and causes of death were assessed from health records. Penetrance, survival, and cancer incidence were ascertained from diagnosed cases, insurance- and cancer registry data. Outcomes were compared with a propensity score-matched control population.

RESULTS

Median age at diagnosis in 542 p.C282Y homozygous individuals was 47.8 years (64% male). At genotyping, the prevalence of iron overload was 55%. The cumulative penetrance of haemochromatosis defined as the presence of provisional iron overload was 24.2% in males and 10.5% in females aged 60 years or younger. Among p.C282Y homozygotes of the same ages, the cumulative proportion of individuals without fibrosis (FIB-4 score < 1.3) was 92.8% in males and 96.7% in females. Median life expectancy was reduced by 6.8 years in individuals homozygous for p.C282Y when compared with population-matched controls (p = .001). Hepatocellular carcinoma incidence was not significantly higher in p.C282Y homozygotes than in controls matched for age and sex.

CONCLUSION

Reduced survival and the observed age-dependent increase in penetrance among p.C282Y homozygotes call for earlier diagnosis of haemochromatosis to prevent complications.

Hemochromatosis: Ferroptosis, ROS, Gut Microbiome, and Clinical Challenges with Alcohol as Confounding Variable

Hemochromatosis represents clinically one of the most important genetic storage diseases of the liver caused by iron overload, which is to be differentiated from hepatic iron overload due to excessive iron release from erythrocytes in patients with genetic hemolytic disorders. This disorder is under recent mechanistic discussion regarding ferroptosis, reactive oxygen species (ROS), the gut microbiome, and alcohol abuse as a risk factor, which are all topics of this review article. Triggered by released intracellular free iron from ferritin via the autophagic process of ferritinophagy, ferroptosis is involved in hemochromatosis as a specific form of iron-dependent regulated cell death. This develops in the course of mitochondrial injury associated with additional iron accumulation, followed by excessive production of ROS and lipid peroxidation. A low fecal iron content during therapeutic iron depletion reduces colonic inflammation and oxidative stress. In clinical terms, iron is an essential trace element required for human health. Humans cannot synthesize iron and must take it up from iron-containing foods and beverages. Under physiological conditions, healthy individuals allow for iron homeostasis by restricting the extent of intestinal iron depending on realistic demand, avoiding uptake of iron in excess. For this condition, the human body has no chance to adequately compensate through removal. In patients with hemochromatosis, the molecular finetuning of intestinal iron uptake is set off due to mutations in the high-FE2+ (HFE) genes that lead to a lack of hepcidin or resistance on the part of ferroportin to hepcidin binding. This is the major mechanism for the increased iron stores in the body. Hepcidin is a liver-derived peptide, which impairs the release of iron from enterocytes and macrophages by interacting with ferroportin. As a result, iron accumulates in various organs including the liver, which is severely injured and causes the clinically important hemochromatosis. This diagnosis is difficult to establish due to uncharacteristic features. Among these are asthenia, joint pain, arthritis, chondrocalcinosis, diabetes mellitus, hypopituitarism, hypogonadotropic hypogonadism, and cardiopathy. Diagnosis is initially suspected by increased serum levels of ferritin, a non-specific parameter also elevated in inflammatory diseases that must be excluded to be on the safer diagnostic side. Diagnosis is facilitated if ferritin is combined with elevated fasting transferrin saturation, genetic testing, and family screening. Various diagnostic attempts were published as algorithms. However, none of these were based on evidence or quantitative results derived from scored key features as opposed to other known complex diseases. Among these are autoimmune hepatitis (AIH) or drug-induced liver injury (DILI). For both diseases, the scored diagnostic algorithms are used in line with artificial intelligence (AI) principles to ascertain the diagnosis. The first-line therapy of hemochromatosis involves regular and life-long phlebotomy to remove iron from the blood, which improves the prognosis and may prevent the development of end-stage liver disease such as cirrhosis and hepatocellular carcinoma. Liver transplantation is rarely performed, confined to acute liver failure. In conclusion, ferroptosis, ROS, the gut microbiome, and concomitant alcohol abuse play a major contributing role in the development and clinical course of genetic hemochromatosis, which requires early diagnosis and therapy initiation through phlebotomy as a first-line treatment.

Identification of SLC40A1, LCN2, CREB5, and SLC7A11 as ferroptosis-related biomarkers in alopecia areata through machine learning

Alopecia areata (AA) is a common non-scarring hair loss condition driven by the collapse of immune privilege and oxidative stress. The role of ferroptosis, a type of cell death linked to oxidative stress, in AA is yet to be explored, even though it's implicated in various diseases. Using transcriptome data from AA patients and controls from datasets GSE68801 and GSE80342, we aimed to identify AA diagnostic marker genes linked to ferroptosis. We employed Single-sample gene set enrichment analysis (ssGSEA) for immune cell infiltration evaluation. Correlations between ferroptosis-related differentially expressed genes (FRDEGs) and immune cells/functions were identified using Spearman analysis. Feature selection was done through Support vector machine-recursive feature elimination (SVM-RFE) and LASSO regression models. Validation was performed using the GSE80342 dataset, followed by hierarchical internal validation. We also constructed a nomogram to assess the predictive ability of FRDEGs in AA. Furthermore, the expression and distribution of these molecules were confirmed through immunofluorescence. Four genes, namely SLC40A1, LCN2, CREB5, and SLC7A11, were identified as markers for AA. A prediction model based on these genes showed high accuracy (AUC = 0.9052). Immunofluorescence revealed reduced expression of these molecules in AA patients compared to normal controls (NC), with SLC40A1 and CREB5 showing significant differences. Notably, they were primarily localized to the outer root sheath and in proximity to the sebaceous glands. Our study identified several ferroptosis-related genes associated with AA. These findings, emerging from the integration of immune cell infiltration analysis and machine learning, contribute to the evolving understanding of diagnostic and therapeutic strategies in AA. Importantly, this research lays a solid foundation for subsequent studies exploring the intricate relationship between AA and ferroptosis.

Eicosanoids and Oxylipin Signature in Hereditary Hemochromatosis Patients Are Similar to Dysmetabolic Iron Overload Syndrome Patients but Are Impacted by Dietary Iron Absorption

INTRODUCTION

Oxylipins are mediators of oxidative stress. To characterize the underlying inflammatory processes and phenotype effect of iron metabolism disorders, we investigated the oxylipin profile in hereditary hemochromatosis (HH) and dysmetabolic iron overload syndrome (DIOS) patients.

METHODS

An LC-MS/MS-based method was performed to quantify plasma oxylipins in 20 HH and 20 DIOS patients in fasting conditions and 3 h after an iron-rich meal in HH patients.

RESULTS

Principal component analysis showed no separation between HH and DIOS, suggesting that the clinical phenotype has no direct impact on oxylipin metabolism. 20-HETE was higher in DIOS and correlated with hypertension (p = 0.03). Different oxylipin signatures were observed in HH before and after the iron-rich meal. Discriminant oxylipins include epoxy fatty acids derived from docosahexaenoic acid and arachidonic acid as well as 13-HODE and 9-HODE. Mediation analysis found no major contribution of dietary iron absorption for 16/22 oxylipins significantly affected by the meal.

DISCUSSION

The oxylipin profiles of HH and DIOS seemed similar except for 20-HETE, possibly reflecting different hypertension prevalence between the two groups. Oxylipins were significantly affected by the iron-rich meal, but the specific contribution of iron was not clear. Although iron may contribute to oxidative stress and inflammation in HH and DIOS, this does not seem to directly affect oxylipin metabolism.

Environmentally sustainable synthesis of whey-based carbon dots for ferric ion detection in human serum and water samples: evaluating the greenness of the method

Carbon dots (CDs) are valued for their biocompatibility, easy fabrication, and distinct optical characteristics. The current study examines using whey to fabricate CDs using the hydrothermal method. When stimulated at 350 nm, the synthetic CDs emitted blue light at 423 nm and revealed a selective response to ferric ion (Fe3+) in actual samples with great sensitivity, making them a suitable probe for assessing Fe3+ ions. The produced carbon dots demonstrated great photostability, high sensitivity, and outstanding biocompatibility. The findings showed that Fe3+ ions could be quickly, sensitively, and extremely selectively detected in an aqueous solution of carbon dots, with a revealing limit of 0.409 μM in the linear range of 0-180 μM. Interestingly, this recognition boundary is far inferior to the WHO-recommended threshold of 0.77 μM. Two metric tools which were AGREE and the ComplexGAPI were also used to evaluate the method's greenness. The evaluation confirmed its superior environmental friendliness.

Paroxysmal atrial fibrillation and hemochromatosis: a narrative review

Paroxysmal atrial fibrillation (PAF) and hemochromatosis have a complex relationship. This review explores its mechanisms, prevalence, correlations, and clinical manifestations. Hereditary hemochromatosis (HH) involves iron overload due to HFE protein mutations, while atrial fibrillation (AF) is characterized by irregular heart rhythms. Iron overload in hemochromatosis can promote cardiac arrhythmias. AF is prevalent in developed countries and may be linked to cryptogenic strokes. Genetic variations and demographic factors influence the occurrence of both conditions. HH affects multiple organ systems, including the heart, while AF causes palpitations and reduced exercise tolerance. Diagnosis involves iron markers, genotypic testing, and electrocardiogram (ECG) findings. Treatment strategies focus on reducing iron levels in hemochromatosis and managing AF through antithrombotic therapy and rhythm control. Untreated hemochromatosis carries a higher risk of complications, and PAF is associated with increased cardiovascular-related mortality. For better understanding of the mechanisms and to improve management, additional studies are required. Tailored approaches and combined treatments may enhance patient outcomes.

An Iron-chelating Agent Improved the Cardiac Function in a Patient with Severe Heart Failure Due to Hereditary Hemochromatosis

A 24-year-old man was admitted to our hospital because of severe heart failure. Although he was treated with diuretics and positive inotropic agents, his heart failure progressed. An endomyocardial biopsy revealed iron deposition in his myocytes. Finally, he was diagnosed with hereditary hemochromatosis. After starting administration of an iron-chelating agent in addition to conventional treatment for heart failure, his condition improved. We should consider hemochromatosis in heart failure patients with severe right ventricular dysfunction in addition to left ventricular dysfunction.

Transmembrane serine protease 6, a novel target for inhibition of neuronal tumor growth

Transmembrane serine protease 6 (Tmprss6) has been correlated with the occurrence and progression of tumors, but any specific molecular mechanism linking the enzyme to oncogenesis has remained elusive thus far. In the present study, we found that Tmprss6 markedly inhibited mouse neuroblastoma N2a (neuro-2a) cell proliferation and tumor growth in nude mice. Tmprss6 inhibits Smad1/5/8 phosphorylation by cleaving the bone morphogenetic protein (BMP) co-receptor, hemojuvelin (HJV). Ordinarily, phosphorylated Smad1/5/8 binds to Smad4 for nuclear translocation, which stimulates the expression of hepcidin, ultimately decreasing the export of iron through ferroportin 1 (FPN1). The decrease in cellular iron levels in neuro-2a cells with elevated Tmprss6 expression limited the availability of the metal forribo nucleotide reductase activity, thereby arresting the cell cycle prior to S phase. Interestingly, Smad4 promoted nuclear translocation of activating transcription factor 3 (ATF3) to activate the p38 mitogen-activated protein kinases signaling pathway by binding to ATF3, inducing apoptosis of neuro-2a cells and inhibiting tumor growth. Disruption of ATF3 expression significantly decreased apoptosis in Tmprss6 overexpressed neuro-2a cells. Our study describes a mechanism whereby Tmprss6 regulates the cell cycle and apoptosis. Thus, we propose Tmprss6 as a candidate target for inhibiting neuronal tumor growth.

Blood donor biobank as a resource in personalised biomedical genetic research

Health questionnaires and donation criteria result in accumulation of highly selected individuals in a blood donor population. To understand better the usefulness of a blood donor-based biobank in personalised disease-associated genetic studies, and for possible personalised blood donation policies, we evaluated the occurrence and distributions of common and rare disease-associated genetic variants in Finnish Blood Service Biobank. We analysed among 31,880 blood donors the occurrence and geographical distribution of (i) 53 rare Finnish-enriched disease-associated variants, (ii) mutations assumed to influence blood donation: four Bernard-Soulier syndrome and two hemochromatosis mutations, (iii) type I diabetes risk genotype HLA-DQ2/DQ8. In addition, we analysed the level of consanguinity in Blood Service Biobank. 80.3% of blood donors carried at least one (range 0-9 per donor) of the rare variants, many in homozygous form, as well. Donors carrying multiple rare variants were enriched in Eastern Finland. Haemochromatosis mutation HFE C282Y homozygosity was 43.8% higher than expected, whereas mutations leading to Bernard-Soulier thrombocytopenia were rare. The frequency of HLA-DQ2/DQ8 genotype was slightly lower than expected. First-degree consanguinity was higher in Blood Service Biobank than in the general population. We demonstrate that despite donor selection, the Blood Service Biobank is a valuable resource for personalised medical research and for genotype-selected samples from unaffected individuals. The geographical genetic substructure of Finland enables efficient recruitment of donors carrying rare variants. Furthermore, we show that blood donor biobank material can be utilised for personalised blood donation policies.

Genetically determined circulating micronutrients and the risk of nonalcoholic fatty liver disease

Evidence from epidemiological literature on the association of circulating micronutrients with risk of nonalcoholic fatty liver disease (NAFLD) is inconsistent. We aimed to elucidate the causal relationships using Mendelian randomization (MR). Single-nucleotide polymorphisms associated with 14 circulating micronutrients (β-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B6, B12, C, D, K1 and zinc) were employed as instrumental variables. Summary level data for NAFLD were obtained from a genome-wide association study (GWAS) meta-analysis of 8434 cases and 770,180 controls (discovery stage) and another two datasets including 1483 NAFLD cases and 17,781 controls (replication stage 1) and 2134 NAFLD cases and 33,433 controls (replication stage 2). Inverse variance-weighted method (IVW) was used as primary analysis, supplemented with a series of sensitivity analysis. Genetically predicted higher β‑carotene levels were suggestively associated with reduced NAFLD risk [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.66-0.99; P = 0.047], whereas the association did not survive the false discovery rates (FDR) correction (PFDR = 0.164). Genetically predicted circulating iron (OR 1.16, 95% CI 1.05-1.29; P = 0.006, PFDR = 0.028), selenium (OR 1.11, 95% CI 1.03-1.20; P = 0.005, PFDR = 0.028) and vitamin B12 (OR 1.08, 95% CI 1.03-1.13; P = 0.002, PFDR = 0.028) were significantly associated with increased risk of NAFLD. Moreover, the findings were consistent in individual datasets (Pheterogeneity > 0.05) and confirmed in sensitivity analysis. Our study provided evidence that circulating iron, selenium and vitamin B12 might be causally linked to the risk of NAFLD, which deserves further exploration of the potential biological mechanism.

Haemochromatosis in children: A national retrospective cohort promoted by the A.I.E.O.P. (Associazione Italiana Emato-Oncologia Pediatrica) study group

Haemochromatosis (HC) encompasses a range of genetic disorders. HFE-HC is by far the most common in adults, while non-HFE types are rare due to mutations of HJV, HAMP, TFR2 and gain-of-function mutations of SLC40A1. HC is often unknown to paediatricians as it is usually asymptomatic in childhood. We report clinical and biochemical data from 24 paediatric cases of HC (10 cases of HFE-, 5 TFR2-, 9 HJV-HC), with a median follow-up of 9.6 years. Unlike in the adult population, non-HFE-HC constitutes 58% (14/24) of the population in our series. Transferrin saturation was significantly higher in TFR2- and HJV-HC compared to HFE-HC, and serum ferritin and LIC were higher in HJV-HC compared to TFR2- and HFE-HC. Most HFE-HC subjects had relatively low ferritin and LIC at the time of diagnosis, so therapy could be postponed for most of them after the age of 18. Our results confirm that HJV-HC is a severe form already in childhood, emphasizing the importance of early diagnosis and treatment to avoid the development of organ damage and reduce morbidity and mortality. Although phlebotomies were tolerated by most patients, oral iron chelators could be a valid option in early-onset HC.

Hyperferritinemia and liver iron content determined with MRI: Reintroduction of the liver iron index

BACKGROUND

Hyperferritinemia is found in around 12 % of the general population. Analyzing the cause can be difficult. In case of doubt about the presence of major iron overload most guidelines advice to perform a MRI as a reliable non-invasive marker to measure liver iron concentration (LIC). In general, a LIC of ≥ 36 µmol/g dw is considered the be elevated however in hyperferritinemia associated with, for example, obesity or alcohol (over)consumption the LIC can be ≥ 36 µmol/g dw in abscence of major iron overload. So, unfortunately a clear cut-off value to differentiate iron overload from normal iron content is lacking. Previously the liver iron index (LII) (LIC measured in liver biopsy (LIC-b)/age (years)), was introduced to differentiate between patients with major (LII ≥ 2) and minor or no iron overload (LII < 2). Based on the good correlation between the LIC-b and LIC determined with MRI (LIC-MRI), our goal was to investigate whether a LII_MRI ≥ 2 is a good indicator of major iron overload, reflected by a significantly higher amount of iron needed to be mobilized to reach iron depletion.

METHODS

We compared the amount of mobilized iron to reach depletion and inflammation-related characteristics in two groups: LII-MRI ≥ 2 versus LII-MRI <2 in 92 hyperferritinemia patients who underwent HFE genotyping and MRI-LIC determination.

RESULTS

Significantly more iron needed to be mobilized to reach iron depletion in the LII ≥ 2 group (mean 4741, SD ± 4135 mg) versus the LII-MRI <2 group (mean 1340, SD ± 533 mg), P < 0.001. Furthermore, hyperferritinemia in LII-MRI < 2 patients was more often related to components of the metabolic syndrome while hyperferritinemia in LII-MRI ≥ 2 patients was more often related to HFE mutations. ROC curve analysis showed good performance of LII =2 as cut-off value. However the calculations showed that the optimal cut-off for the LII = 3.4.

CONCLUSION

The LII-MRI with a cut-off value of 2 is an effective method to differentiate major from minor iron overload in patients with hyperferritinemia. But the LII-MRI = 3.4 seems a more promising diagnostic test for major iron overload.

Rusfertide for the treatment of iron overload in HFE-related haemochromatosis: an open-label, multicentre, proof-of-concept phase 2 trial

BACKGROUND

Hereditary haemochromatosis protein (HFE)-related haemochromatosis, an inherited iron overload disorder caused by insufficient hepcidin production, results in excessive iron absorption and tissue and organ injury, and is treated with first-line therapeutic phlebotomy. We aimed to investigate the efficacy and safety of rusfertide, a peptidic mimetic of hepcidin, in patients with HFE-related haemochromatosis.

METHODS

This open-label, multicentre, proof-of-concept phase 2 trial was done across nine academic and community centres in the USA and Canada. Adults (aged ≥18 years) with HFE-related haemochromatosis on a stable therapeutic phlebotomy regimen (maintenance phase) for at least 6 months before screening and who had a phlebotomy frequency of at least 0·25 per month (eg, at least three phlebotomies in 12 months or at least four phlebotomies in 15 months) and less than one phlebotomy per month, with serum ferritin of less than 300 ng/mL and haemoglobin of more than 11·5 g/dL, were eligible. Patients initiated 24 weeks of subcutaneous rusfertide treatment within 7 days of a scheduled phlebotomy at 10 mg once weekly. Rusfertide doses and dosing schedules could be adjusted to maintain serum transferrin iron saturation (TSAT) at less than 40%. During rusfertide treatment, investigators were to consider the need for phlebotomy when the serum ferritin and TSAT values exceeded the patient's individual pre-phlebotomy serum ferritin and TSAT values. No primary endpoint or testing hierarchy was prespecified. Prespecified efficacy endpoints included the change in the frequency of phlebotomies; the proportion of patients achieving phlebotomy independence; change in serum iron, TSAT, serum transferrin, serum ferritin, and liver iron concentration (LIC) as measured by MRI; and treatment-emergent adverse events (TEAEs). The key efficacy analyses for phlebotomy rate and LIC were conducted by use of paired t tests in the intention-to-treat population, defined as all patients who received any study drug and who had pretreatment and at least one post-dose measurement. We included all participants who received at least one dose of rusfertide in the safety analyses. This trial is closed and completed and is registered with ClinicalTrials.gov, NCT04202965.

FINDINGS

Between March 11, 2020, and April 23, 2021, 28 patients were screened and 16 (ten [63%] men and six [38%] women) were enrolled. 16 were included in analyses of phlebotomy endpoints and 14 for the LIC endpoint. 12 (75%) patients completed 24 weeks of treatment. The mean number of phlebotomies was significantly reduced during the 24-week rusfertide treatment (0·06 phlebotomies [95% CI -0·07 to 0·20]) compared with 24 weeks pre-study (2·31 phlebotomies [95% CI 1·77 to 2·85]; p<0·0001). 15 (94%) of 16 patients were phlebotomy-free during the treatment period. Mean LIC in the 14 patients in the intention-to-treat population was 1·4 mg iron per g dry liver weight (95% CI 1·0 to 1·8) at screening and 1·1 mg iron per g dry liver weight (95% CI 0·9 to 1·3) at the end of treatment (p=0·068). Mean TSAT was 45·3% (95% CI 33·2 to 57·3) at screening, 36·7% (24·2 to 49·2) after the pretreatment phlebotomy, 21·8% (15·8 to 27·9) 24 h after the first dose of rusfertide, 40·4% (27·1 to 53·8) at the end of treatment, and 32·6% (25·0 to 40·1) over the treatment duration. Mean serum iron was 24·6 μmol/L (95% CI 18·6 to 30·6), 20·1 μmol/L (14·8 to 25·3), 11·9 μmol/L (9·2 to 14·7), 22·5 μmol/L (15·9 to 29·1), and 19·0 μmol/L (15·3 to 22·6) at these same timepoints, respectively. Mean serum ferritin was 83·3 μg/L (52·2 to 114.4), 65·5 μg/L (32·1 to 98·9), 62·8 μg/L (33·8 to 91·9), 150·0 μg/L (86·6 to 213.3), and 94·3 μg/L (54·9 to 133.6) at these same timepoints, respectively. There were only minor changes in serum transferrin concentration. 12 (75%) patients had at least one TEAE, the most common of which was injection site pain (five [31%] patients). All TEAEs were mild or moderate in severity, except for a serious adverse event of pancreatic adenocarcinoma, which was considered severe and unrelated to treatment and was pre-existing and diagnosed 21 days after starting rusfertide treatment.

INTERPRETATION

Rusfertide prevents iron re-accumulation in the absence of phlebotomies and could be a viable therapeutic option for selected patients with haemochromatosis.

FUNDING

Protagonist Therapeutics.

T2* map at cardiac MRI reveals incidental hepatic and cardiac iron overload

PURPOSE

The purpose of this study was to assess the diagnostic capabilities of cardiac magnetic resonance (CMR) T2* mapping in detecting incidental hepatic and cardiac iron overload.

MATERIALS AND METHODS

Patients with various clinical indications for CMR examination were consecutively included at a single center from January 2019 to April 2023. All patients underwent T2* mapping at 1.5 T in a single mid-ventricular short-axis as part of a comprehensive routine CMR protocol. T2* measurements were performed of the heart (using a region-of-interest in the interventricular septum) and the liver, categorized according to the severity of iron overload. The degree of cardiac iron overload was categorized as mild (15 ms < T2* < 20 ms), moderate (10 ms < T2* < 15 ms) and severe (T2* < 10 ms). The degree of hepatic iron overload was categorized as mild (4 ms < T2* < 8 ms), moderate (2 ms < T2* < 4 ms), severe (T2* < 2 ms). Image quality and inter-reader agreement were assessed using intraclass correlation coefficient (ICC).

RESULTS

CMR examinations from 614 patients (374 men, 240 women) with a mean age of 50 ± 18 (standard deviation) years were fully evaluable. A total of 24/614 patients (3.9%) demonstrated incidental hepatic iron overload; of these, 22/614 patients (3.6%) had mild hepatic iron overload, and 2/614 patients (0.3%) had moderate hepatic iron overload. Seven out of 614 patients (1.1%) had incidental cardiac iron overload; of these, 5/614 patients (0.8%) had mild iron overload, 1/614 patients (0.2%) had moderate iron overload, and 1/614 patients (0.2%) had severe iron overload. Good to excellent inter-reader agreement was observed for the assessment of T2* values (ICC, 0.90 for heart [95% confidence interval: 0.88-0.91]; ICC, 0.91 for liver [95% confidence interval: 0.89-0.92]).

CONCLUSION

Analysis of standard CMR T2* maps detects incidental cardiac and hepatic iron overload in 1.1% and 3.9% of patients, respectively, which may have implications for further patient management. Therefore, despite an overall low number of incidental abnormal findings, T2* imaging may be included in a standardized comprehensive CMR protocol.

Liver Iron Loading in Alcohol-Associated Liver Disease

Alcohol-associated liver disease (ALD) is a common chronic liver disease with increasing incidence worldwide. Alcoholic liver steatosis/steatohepatitis can progress to liver fibrosis/cirrhosis, which can cause predisposition to hepatocellular carcinoma. ALD diagnosis and management are confounded by several challenges. Iron loading is a feature of ALD which can exacerbate alcohol-induced liver injury and promote ALD pathologic progression. Knowledge of the mechanisms that mediate liver iron loading can help identify cellular/molecular targets and thereby aid in designing adjunct diagnostic, prognostic, and therapeutic approaches for ALD. Herein, the cellular mechanisms underlying alcohol-induced liver iron loading are reviewed and how excess iron in patients with ALD can promote liver fibrosis and aggravate disease pathology is discussed. Alcohol-induced increase in hepatic transferrin receptor-1 expression and up-regulation of high iron protein in Kupffer cells (proposed) facilitate iron deposition and retention in the liver. Iron is loaded in both parenchymal and nonparenchymal liver cells. Iron-loaded liver can promote ferroptosis and thereby contribute to ALD pathology. Iron and alcohol can independently elevate oxidative stress. Therefore, a combination of excess iron and alcohol amplifies oxidative stress and accelerates liver injury. Excess iron-stimulated hepatocytes directly or indirectly (through Kupffer cell activation) activate the hepatic stellate cells via secretion of proinflammatory and profibrotic factors. Persistently activated hepatic stellate cells promote liver fibrosis, and thereby facilitate ALD progression.

Fatty infiltration of the pancreas: a systematic concept analysis

Fatty infiltration of the pancreas (FIP) has been recognized for nearly a century, yet many aspects of this condition remain unclear. Regular literature reviews on the diagnosis, consequences, and management of FIP are crucial. This review article highlights the various disorders for which FIP has been established as a risk factor, including type 2 diabetes mellitus (T2DM), pancreatitis, pancreatic fistula (PF), metabolic syndrome (MS), polycystic ovary syndrome (PCOS), and pancreatic duct adenocarcinoma (PDAC), as well as the new investigation tools. Given the interdisciplinary nature of FIP research, a broad range of healthcare specialists are involved. This review article covers key aspects of FIP, including nomenclature and definition of pancreatic fat infiltration, history and epidemiology, etiology and pathophysiology, clinical presentation and diagnosis, clinical consequences, and treatment. This review is presented in a detailed narrative format for accessibility to clinicians and medical students.

Hematinic Potential of Olive Leaf Extract: Evidence from an In Vivo Study in Mice and a Pilot Study in Healthy Human Volunteers

Natural resources have recently received considerable attention as complementary or alternative hematinic agents. In this regard, olive leaf extract, which is rich in bioactive phenolic compounds, has been reported to induce erythroid differentiation in human hematopoietic stem cells. Therefore, in the present study, we aimed to explore the potential hematinic properties of aqueous olive leaf extract (WOL) in vivo. After 24 days of administering WOL to healthy mice orally, red blood cell (RBC), hematocrit, reticulocyte, and reticulocyte hemoglobin content (CHr) showed a significant increase. Additionally, WOL promoted plasma iron levels and the expression of splenic ferroportin (Fpn), an iron transporter. Additionally, a single-arm pilot study involving a limited number of healthy volunteers was conducted to assess WOL's feasibility, compliance, and potential benefits. Following an 8-week intervention with WOL, RBC count and hemoglobin level were significantly increased. Notably, there were no significant changes in the safety measures related to liver and kidney functions. Furthermore, we identified oleuropein and oleuroside as the active components in WOL to induce erythroid differentiation in the K562 cell line. Altogether, our study presents evidence of the hematinic potential of WOL in the in vivo studies, opening up exciting possibilities for future applications in preventing or treating anemia.

Porphyria cutanea tarda: an under-recognised manifestation of haemochromatosis

We present a case of a woman who presented with a photosensitive skin rash and blisters on her extremities which did not improve with steroids. These were associated with polyarthralgia and a deranged liver function test on her admission. Further workup revealed that the patient has an undiagnosed porphyria cutanea tarda (PCT) and hereditary haemochromatosis. The patient later underwent regular venesections which improved her condition. This case report not only illustrates the challenge in diagnosing PCT but also aims to highlight the association between PCT and hereditary haemochromatosis.

Myeloid Hif2α is not essential to maintain systemic iron homeostasis

Dietary consumption serves as the primary source of iron uptake, and erythropoiesis acts as a major regulator of systemic iron demand. In addition to intestinal iron absorption, macrophages play a crucial role in recycling iron from senescent red blood cells. The kidneys are responsible for the production of erythropoietin (Epo), which stimulates erythropoiesis, whereas the liver plays a central role in producing the iron-regulatory hormone hepcidin. The transcriptional regulator hypoxia-inducible factor (HIF)2α has a central role in the regulation of Epo, hepcidin, and intestinal iron absorption and therefore plays a crucial role in coordinating the tissue crosstalk to maintain systemic iron demands. However, the precise involvement of Hif2α in macrophages in terms of iron homeostasis remains uncertain. Our study demonstrates that deleting Hif2α in macrophages does not disrupt the expression of iron transporters or basal erythropoiesis. Mice lacking Hif2α in myeloid cells exhibited no discernible differences in hemodynamic parameters, including hemoglobin concentrations and erythrocyte count, when compared with littermate controls. This similarity was observed under conditions of both dietary iron deficiency and acute erythropoietic demand. Notably, we observed a significant increase in the expression of iron transporters in the duodenum during iron deficiency, indicating heightened iron absorption. Therefore, our findings suggest that the disruption of Hif2α in myeloid cells does not significantly impact systemic iron homeostasis under normal physiologic conditions. However, its disruption induces adaptive physiologic changes in response to elevated iron demand, potentially serving as a mechanism to sustain increased erythropoietic demand.

Overview of Ankle Arthropathy in Hereditary Hemochromatosis

Hereditary hemochromatosis (HH) is an autosomal recessive bleeding disorder characterized by tissue overload of iron. Clinical systemic manifestations in HH include liver disease, cardiomyopathy, skin pigmentation, diabetes mellitus, erectile dysfunction, hypothyroidism, and arthropathy. Arthropathy with joint pain is frequently reported at diagnosis and mainly involves the metacarpophalangeal and ankle joints, and more rarely, the hip and knee. Symptoms in ankle joints are in most cases non-specific, and they can range from pain and swelling of the ankle to deformities and joint destruction. Furthermore, the main radiological signs do not differ from those of primary osteoarthritis (OA). Limited data are available in the literature regarding treatment; surgery seems to be the gold standard for ankle arthropathy in HH. Pharmacological treatments used to maintain iron homeostasis can also be undertaken to prevent the arthropathy, but conclusive data are not yet available. This review aimed to assess the ankle arthropathy in the context of HH, including all its aspects: epidemiology, physiopathology, clinical and imaging presentation, and all the treatments available to the current state of knowledge.

Joint manifestations revealing inborn metabolic diseases in adults: a narrative review

Inborn metabolic diseases (IMD) are rare conditions that can be diagnosed during adulthood. Patients with IMD may have joint symptoms and the challenge is to establish an early diagnosis in order to institute appropriate treatment and prevent irreversible damage. This review describes the joint manifestations of IMD that may be encountered in adults. The clinical settings considered were arthralgia and joint stiffness as well as arthritis. Unspecific arthralgias are often the first symptoms of hereditary hemochromatosis, chronic low back pain may reveal an intervertebral disc calcification in relation with alkaptonuria, and progressive joint stiffness may correspond to a mucopolysaccharidosis or mucolipidosis. Gaucher disease is initially revealed by painful acute attacks mimicking joint pain described as "bone crises". Some IMD may induce microcrystalline arthropathy. Beyond classical gout, there are also gouts in connection with purine metabolism disorders known as "enzymopathic gouts". Pyrophosphate arthropathy can also be part of the clinical spectrum of Gitelman syndrome or hypophosphatasia. Oxalate crystals arthritis can reveal a primary hyperoxaluria. Destructive arthritis may be indicative of Wilson's disease. Non-destructive arthritis may be seen in mevalonate kinase deficiency and familial hypercholesterolemia.

Increasing serum iron levels and their role in the risk of infectious diseases: a Mendelian randomization approach

OBJECTIVES

Increased iron stores have been associated with elevated risks of different infectious diseases, suggesting that iron supplementation may increase the risk of infections. However, these associations may be biased by confounding or reverse causation. This is important, since up to 19% of the population takes iron supplementation. We used Mendelian randomization (MR) to bypass these biases and estimate the causal effect of iron on infections.

METHODS

As instrumental variables, we used genetic variants associated with iron biomarkers in two genome-wide association studies (GWASs) of European ancestry participants. For outcomes, we used GWAS results from the UK Biobank, FinnGen, the COVID-19 Host Genetics Initiative or 23andMe, for seven infection phenotypes: 'any infections', combined, COVID-19 hospitalization, candidiasis, pneumonia, sepsis, skin and soft tissue infection (SSTI) and urinary tract infection (UTI).

RESULTS

Most of our analyses showed increasing iron (measured by its biomarkers) was associated with only modest changes in the odds of infectious outcomes, with all 95% odds ratios confidence intervals within the 0.88 to 1.26 range. However, for the three predominantly bacterial infections (sepsis, SSTI, UTI), at least one analysis showed a nominally elevated risk with increased iron stores (P <0.05).

CONCLUSION

Using MR, we did not observe an increase in risk of most infectious diseases with increases in iron stores. However for bacterial infections, higher iron stores may increase odds of infections. Hence, using genetic variation in iron pathways as a proxy for iron supplementation, iron supplements are likely safe on a population level, but we should continue the current practice of conservative iron supplementation during bacterial infections or in those at high risk of developing them.

Iron homeostasis governs erythroid phenotype in polycythemia vera

Polycythemia vera (PV) is a myeloproliferative neoplasm driven by activating mutations in JAK2 that result in unrestrained erythrocyte production, increasing patients' hematocrit and hemoglobin concentrations, placing them at risk of life-threatening thrombotic events. Our genome-wide association study of 440 PV cases and 403 351 controls using UK Biobank data showed that single nucleotide polymorphisms in HFE known to cause hemochromatosis are highly associated with PV diagnosis, linking iron regulation to PV. Analysis of the FinnGen dataset independently confirmed overrepresentation of homozygous HFE variants in patients with PV. HFE influences the expression of hepcidin, the master regulator of systemic iron homeostasis. Through genetic dissection of mouse models of PV, we show that the PV erythroid phenotype is directly linked to hepcidin expression: endogenous hepcidin upregulation alleviates erythroid disease whereas hepcidin ablation worsens it. Furthermore, we demonstrate that in PV, hepcidin is not regulated by expanded erythropoiesis but is likely governed by inflammatory cytokines signaling via GP130-coupled receptors. These findings have important implications for understanding the pathophysiology of PV and offer new therapeutic strategies for this disease.

The ancestral haplotype markers HLA -A3 and B7 do not influence the likelihood of advanced hepatic fibrosis or cirrhosis in HFE hemochromatosis

Advanced hepatic fibrosis occurs in up to 25% of individuals with C282Y homozygous hemochromatosis. Our aim was to determine whether human leukocyte antigen (HLA)-A3 and B7 alleles act as genetic modifiers of the likelihood of advanced hepatic fibrosis. Between 1972 and 2013, 133 HFE C282Y homozygous individuals underwent clinical and biochemical evaluation, HLA typing, liver biopsy for fibrosis staging and phlebotomy treatment. Hepatic fibrosis was graded according to Scheuer as F0-2 (low grade hepatic fibrosis), F3-4 (advanced hepatic fibrosis), and F4 cirrhosis. We analysed associations between the severity of fibrosis and HLA-A3 homozygosity, heterozygosity or absence, with or without the presence of HLA-B7 using categorical analysis. The mean age of HLA-A3 homozygotes (n = 24), heterozygotes (n = 65) and HLA-A3 null individuals (n = 44) was 40 years. There were no significant differences between the groups for mean(± SEM) serum ferritin levels (1320 ± 296, 1217 ± 124, 1348 ± 188 [Formula: see text]g/L), hepatic iron concentration (178 ± 26, 213 ± 22, 199 ± 29 [Formula: see text]mol/g), mobilizable iron stores (9.9 ± 1.5, 9.5 ± 1.5, 11.5 ± 1.7 g iron removed via phlebotomy), frequency of advanced hepatic fibrosis (5/24[12%], 13/63[19%], 10/42[19%]) or cirrhosis (3/24[21%], 12/63[21%], 4/42[24%]), respectively. The presence or absence of HLA-B7 did not influence the outcome. Thus, HLA-A3 and HLA-B7 alleles are not associated with the risk of advanced hepatic fibrosis or cirrhosis in C282Y hemochromatosis.

Biomimetic Molybdenum Sulfide-Catalyzed Tumor Ferroptosis and Bioimaging

The chemical generation of singlet oxygen (¹ O₂ ) by the MoO₄ ^2- -catalyzed disproportionation of hydrogen peroxide (H₂ O₂ ) has been widely applied in numerous catalytic processes; however, such molybdate ions cannot be administered for redox-based cancer therapeutics. This work reports the albumin-mediated biomimetic synthesis of highly active molybdenum sulfide (denoted MoB) nanocatalysts that mediate the simultaneous generation of ¹ O₂ and superoxide anion (O₂ ^•- ) from H₂ O₂ , which is relatively abundant in malignant tumors. The MoB-catalyzed reactive oxygen species (ROS) are able to activate the ferroptosis pathway and cause lipid peroxidation for efficient cancer therapy. Furthermore, for the first time, the catalytic activity of MoB is visualized in situ. Moreover, a catalytic imaging modality based on MoB is developed for specific imaging of inflammation diseases without background interference. Therefore, this study presents a biomimetic strategy toward Mo-based nanocatalysts for ROS-facilitated tumor ferroptosis and catalytic imaging.

Analysis of Hand Joint Space Morphology in Women and Men with Hereditary Hemochromatosis

Hereditary hemochromatosis (HH) causes unbalanced iron deposition in many organs including the joints leading to severe cartilage loss and bone damage in the metacarpophalangeal joints (MCPJ). High-resolution peripheral quantitative computed tomography (HR-pQCT) and its joint space width (JSW) quantification algorithm quantifies in vivo 3D joint morphology. We therefore aimed to (i) determine feasibility and performance of the JSW algorithm in HH, (ii) quantify joint space morphology, and (iii) investigate the relationship between morphological and clinical parameters in HH. Here, we performed an exploratory study on 24 HH patients and sex- and age-matched controls using HR-pQCT imaging of MCPJ. Mineralized bone structure was automatically segmented from the grayscale image data and periosteal surface bone masks and joint space masks were generated. Mean, minimal, and maximal joint space width (JSW; JSW.MIN; JSW.MAX), JSW heterogeneity (JSW.SD), JSW asymmetry (JSW.AS), and joint space volume (JSV) were computed. Demographics and, for HH patients, disease-specific parameters were recorded. Segmentation of JS was very good with 79.7% of MCPJs successfully segmented at first attempt and 20.3% requiring semi-manual correction. HH men showed larger JSV at all MCPs (+ 25.4% < JSV <  + 41.8%, p < 0.05), larger JSW.MAX at MCP 3-4 (+ 14%, 0.006 < p < 0.062), and wider JSW (+ 13%, p = 0.043) at MCP 4 relative to HH women. Compared to controls, both HH men and HH women showed larger JSW.AS and smaller JSW.MIN at all MCP levels, reaching significance for HH men at MCP 2 and 3 (JSW.AS: + 323% < JSW.AS <  + 359%, 0.020 < p < 0.043; JSW.MIN: - 216% < JSW.MIN < - 225%, p < 0.043), and for women at MCP 3 (JSW.AS: + 180%, p = 0.025; JSW.MIN: - 41.8%, p = 0.022). Time since HH diagnosis was correlated positively with MCP 4 JSW.AS and JSW.SD (0.463 < ρ < 0.499, p < 0.040), and the number of phlebotomies since diagnosis was correlated with JSW.SD at all MCPs (0.432 < ρ < 0.535, p < 0.050). HR-pQCT-based JSW quantification in MCPJ of HH patients is feasible, performs well even in narrow JS, and allows to define the microstructural joint burden of HH.

Magnetic Resonance Liver Iron Concentration Can Guide Venesection Decision-Making in Hyperferritinemia

BACKGROUND

The clinical benefit of venesection in suspected iron overload can be unclear and serum ferritin may overestimate the degree of iron overload.

AIMS

To help inform practice, we examined magnetic resonance liver iron concentration (MRLIC) in a cohort investigated for haemochromatosis.

METHODS

One hundred and six subjects with suspected haemochromatosis underwent HFE genotyping and MRLIC with time-matched serum ferritin and transferrin saturation values. For those treated with venesection, volume of blood removed was calculated as a measure of iron overload.

RESULTS

Forty-seven C282Y homozygotes had median ferritin 937 µg/l and MRLIC 4.83 mg/g; MRLIC was significantly higher vs non-homozygotes for any given ferritin concentration. No significant difference in MRLIC was observed between homozygotes with and without additional risk factors for hyperferritinemia. Thirty-three compound heterozygotes (C282Y/H63D) had median ferritin 767 µg/l and MRLIC 2.58 mg/g; ferritin < 750 µg/l showed 100% specificity for lack of significant iron overload (< 3.2 mg/g). 79% of C282Y/H63D had additional risk factors-mean MRLIC was significantly lower in this sub-group (2.4 mg/g vs 3.23 mg/g). 26 C282Y heterozygous or wild-type had median ferritin 1226 µg/l and MRLIC 2.13 mg/g; 69% with additional risk factors had significantly higher ferritin concentrations (with comparable MRLIC) and ferritin < 1000 µg/l showed 100% specificity for lack of significant iron overload. In 31 patients (26 homozygotes, 5 C282Y/H63D) venesected to ferritin < 100 µg/l, MRLIC and total venesection volume correlated strongly (r = 0.749), unlike MRLIC and serum ferritin.

CONCLUSION

MRLIC is an accurate marker of iron overload in haemochromatosis. We propose serum ferritin thresholds in non-homozygotes which, if validated, could tailor cost-effective use of MRLIC in venesection decision-making.

Genetic Variants Determine Treatment Response in Autoimmune Hepatitis

Background: Autoimmune hepatitis (AIH) is a rare entity; in addition, single-nucleotide polymorphisms (SNPs) may impact its course and outcome. We investigated liver-related SNPs regarding its activity, as well as in relation to its stage and treatment response in a Central European AIH cohort. Methods: A total of 113 AIH patients (i.e., 30 male/83 female, median 57.9 years) were identified. In 81, genotyping of PNPLA3-rs738409, MBOAT7-rs626238, TM6SF2-rs58542926, and HSD17B13-rs72613567:TA, as well as both biochemical and clinical data at baseline and follow-up, were available. Results: The median time of follow-up was 2.8 years; five patients died and one underwent liver transplantation. The PNPLA3-G/G homozygosity was linked to a worse treatment response when compared to wildtype [wt] (ALT 1.7 vs. 0.6 × ULN, p < 0.001). The MBOAT7-C/C homozygosity was linked to non-response vs. wt and heterozygosity (p = 0.022). Male gender was associated with non-response (OR 14.5, p = 0.012) and a higher prevalence of PNPLA3 (G/G vs. C/G vs. wt 41.9/40.0/15.0% males, p = 0.03). The MBOAT7 wt was linked to less histological fibrosis (p = 0.008), while no effects for other SNPs were noted. A polygenic risk score was utilized comprising all the SNPs and correlated with the treatment response (p = 0.04). Conclusions: Our data suggest that genetic risk variants impact the treatment response of AIH in a gene-dosage-dependent manner. Furthermore, MBOAT7 and PNPLA3 mediated most of the observed effects, the latter explaining, in part, the predisposition of male subjects to worse treatment responses.

European Association for Study of the Liver (EASL) clinical practice guidelines on haemochromatosis

The European Association for the Study of the Liver has recently updated guidance on haemochromatosis with a more extensive discussion on investigation and management.[ The new guidance focuses on non-invasive methods for fibrosis assessment and early diagnosis to include more extensive genetic testing if needed. Early diagnosis and treatment is vital as it reduces morbidity and mortality. We review this guideline and offer key updated messages with a focus on new developments since the last guidance and key aspects of current practice.

Low-temperature Mössbauer spectroscopy of organs from 57Fe-enriched HFE(-/-) hemochromatosis mice: an iron-dependent threshold for generating hemosiderin

Hereditary hemochromatosis is an iron-overload disease most often arising from a mutation in the Homeostatic Fe regulator (HFE) gene. HFE organs become overloaded with iron which causes damage. Iron-overload is commonly detected by NMR imaging, but the spectroscopic technique is insensitive to diamagnetic iron. Here, we used Mössbauer spectroscopy to examine the iron content of liver, spleen, kidney, heart, and brain of 57Fe-enriched HFE(-/-) mice of ages 3-52 wk. Overall, the iron contents of all investigated HFE organs were similar to the same healthy organ but from an older mouse. Livers and spleens were majorly overloaded, followed by kidneys. Excess iron was generally present as ferritin. Iron-sulfur clusters and low-spin FeII hemes (combined into the central quadrupole doublet) and nonheme high-spin FeII species were also observed. Spectra of young and middle-aged HFE kidneys were dominated by the central quadrupole doublet and were largely devoid of ferritin. Collecting and comparing spectra at 5 and 60 K allowed the presence of hemosiderin, a decomposition product of ferritin, to be quantified, and it also allowed the diamagnetic central doublet to be distinguished from ferritin. Hemosiderin was observed in spleens and livers from HFE mice, and in spleens from controls, but only when iron concentrations exceeded 2-3 mM. Even in those cases, hemosiderin represented only 10-20% of the iron in the sample. NMR imaging can identify iron-overload under non-invasive room-temperature conditions, but Mössbauer spectroscopy of 57Fe-enriched mice can detect all forms of iron and perhaps allow the process of iron-overloading to be probed in greater detail.

Peripheral and Central Iron Measures in Alcohol Use Disorder and Aging: A Quantitative Susceptibility Mapping Pilot Study

Chronic excessive alcohol use has neurotoxic effects, which may contribute to cognitive decline and the risk of early-onset dementia. Elevated peripheral iron levels have been reported in individuals with alcohol use disorder (AUD), but its association with brain iron loading has not been explored. We evaluated whether (1) serum and brain iron loading are higher in individuals with AUD than non-dependent healthy controls and (2) serum and brain iron loading increase with age. A fasting serum iron panel was obtained and a magnetic resonance imaging scan with quantitative susceptibility mapping (QSM) was used to quantify brain iron concentrations. Although serum ferritin levels were higher in the AUD group than in controls, whole-brain iron susceptibility did not differ between groups. Voxel-wise QSM analyses revealed higher susceptibility in a cluster in the left globus pallidus in individuals with AUD than controls. Whole-brain iron increased with age and voxel-wise QSM indicated higher susceptibility with age in various brain areas including the basal ganglia. This is the first study to analyze both serum and brain iron loading in individuals with AUD. Larger studies are needed to examine the effects of alcohol use on iron loading and its associations with alcohol use severity, structural and functional brain changes, and alcohol-induced cognitive impairments.

Interpreting Iron Homeostasis in Congenital and Acquired Disorders

Mammalian cells require iron to satisfy their metabolic needs and to accomplish specialized functions, such as hematopoiesis, mitochondrial biogenesis, energy metabolism, or oxygen transport. Iron homeostasis is balanced by the interplay of proteins responsible for iron import, storage, and export. A misbalance of iron homeostasis may cause either iron deficiencies or iron overload diseases. The clinical work-up of iron dysregulation is highly important, as severe symptoms and pathologies may arise. Treating iron overload or iron deficiency is important to avoid cellular damage and severe symptoms and improve patient outcomes. The impressive progress made in the past years in understanding mechanisms that maintain iron homeostasis has already changed clinical practice for treating iron-related diseases and is expected to improve patient management even further in the future.

Managing the Dual Nature of Iron to Preserve Health

Because of its peculiar redox properties, iron is an essential element in living organisms, being involved in crucial biochemical processes such as oxygen transport, energy production, DNA metabolism, and many others. However, its propensity to accept or donate electrons makes it potentially highly toxic when present in excess and inadequately buffered, as it can generate reactive oxygen species. For this reason, several mechanisms evolved to prevent both iron overload and iron deficiency. At the cellular level, iron regulatory proteins, sensors of intracellular iron levels, and post-transcriptional modifications regulate the expression and translation of genes encoding proteins that modulate the uptake, storage, utilization, and export of iron. At the systemic level, the liver controls body iron levels by producing hepcidin, a peptide hormone that reduces the amount of iron entering the bloodstream by blocking the function of ferroportin, the sole iron exporter in mammals. The regulation of hepcidin occurs through the integration of multiple signals, primarily iron, inflammation and infection, and erythropoiesis. These signals modulate hepcidin levels by accessory proteins such as the hemochromatosis proteins hemojuvelin, HFE, and transferrin receptor 2, the serine protease TMPRSS6, the proinflammatory cytokine IL6, and the erythroid regulator Erythroferrone. The deregulation of the hepcidin/ferroportin axis is the central pathogenic mechanism of diseases characterized by iron overload, such as hemochromatosis and iron-loading anemias, or by iron deficiency, such as IRIDA and anemia of inflammation. Understanding the basic mechanisms involved in the regulation of hepcidin will help in identifying new therapeutic targets to treat these disorders.

HAMP as a Potential Diagnostic, PD-(L)1 Immunotherapy Sensitivity and Prognostic Biomarker in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) remains a global medical problem. Programmed cell death protein 1 (PD-1) is a powerful weapon against many cancers, but it is not sensitive to some patients with HCC. We obtained datasets from the Gene Expression Omnibus (GEO) database on HCC patients and PD-1 immunotherapy to select seven intersecting DEGs. Through Lasso regression, two intersecting genes were acquired as predictors of HCC and PD-1 treatment prognosis, including HAMP and FOS. Logistic regression was performed to build a prediction model. HAMP had a better ability to diagnose HCC and predict PD1 treatment sensitivity. Further, we adapted the support vector machine (SVM) technique using HAMP to predict triple-classified outcomes after PD1 treatment in HCC patients, which had an excellent classification ability. We also performed external validation using TCGA data, which showed that HAMP was elevated in the early stage of HCC. HAMP was positively correlated with the infiltration of 18 major immune cells and the expression of 2 important immune checkpoints, PDCD1 and CTLA4. We discovered a biomarker that can be used for the early diagnosis, prognosis and PD1 immunotherapy efficacy prediction of HCC for the first time and developed a diagnostic model, prognostic model and prediction model of PD1 treatment sensitivity and treatment outcome for HCC patients accordingly.