Serum concentration of ferroportin in women of reproductive age.

Introduction: Ferroportin (Fpn) is the only known iron exporter and plays an essential role in iron homeostasis. Serum concentrations of Fpn in health and/or diseased states are still mostly unknown. Therefore, the aim of this study was to determine the concentration of Fpn in the serum of women of reproductive age (WRA) for the first time, and to establish whether there is a difference in the concentration of Fpn according to ferritin status. Materials and methods: This research included 100 WRA (18-45 years, C-reactive protein (CRP) < 5 mg/L, hemoglobin > 120 g/L). Serum Fpn was measured using Enzyme Linked Immunosorbent Assay (ELISA) method on the analyzer EZ Read 800 Plus (Biochrom, Cambridge, UK). Reference interval was calculated using the robust method. Results: The median concentration of Fpn in the whole study group was 9.74 (5.84-15.69) µg/L. The subgroup with ferritin concentration > 15 µg/L had a median Fpn concentration 15.21 (10.34-21.93) µg/L, which significantly differed from Fpn concentration in the subgroup with ferritin concentration ≤ 15 µg/L (5.93 (4.84-8.36) µg/L, P < 0.001). The reference limits for the Fpn were 2.26-29.81 µg/L with 90% confidence intervals (CI) of 1.78 to 2.83 and 25.37 to 34.33, respectively. Conclusions: The proposed reference interval could help in the future research on iron homeostasis both in physiological conditions and in various disorders, because this is the first study that measured Fpn concentration in a certain gender and age group of a healthy population.

A simple clinical score to promote and enhance ferroportin disease screening.

BACKGROUND & AIMS: Ferroportin disease is a rare genetic iron overload disorder which may be underdiagnosed, with recent data suggesting it occurs at a higher prevalence than suspected. Costs and the lack of defined criteria to prompt genetic testing preclude large-scale molecular screening. Hence, we aimed to develop a readily available scoring system to promote and enhance ferroportin disease screening. METHODS: Our derivation cohort included probands tested for ferroportin disease from 2008 to 2016 in our rare disease network. Data were prospectively recorded. Univariate and multivariate logistic regression were used to determine significant criteria, and odds ratios were used to build a weighted score. A cut-off value was defined using a ROC curve with a predefined aim of 90% sensitivity. An independent cohort was used for cross validation. RESULTS: Our derivation cohort included 1,306 patients. Mean age was 55±14 years, ferritin 1,351±1,357 µg/L, and liver iron concentration (LIC) 166±77 µmol/g. Pathogenic variants (n = 32) were identified in 71 patients. In multivariate analysis: female sex, younger age, higher ferritin, higher LIC and the absence of hypertension or diabetes were significantly associated with the diagnosis of ferroportin disease (AUROC in whole derivation cohort 0.83 [0.78-0.88]). The weighted score was based on sex, age, the presence of hypertension or diabetes, ferritin level and LIC. An AUROC of 0.83 (0.77-0.88) was obtained in the derivation cohort without missing values. Using 9.5 as a cut-off, sensitivity was 93.6 (91.7-98.3) %, specificity 49.5 (45.5-53.6) %, positive likelihood ratio 1.8 (1.6-2.0) and negative likelihood ratio 0.17 (0.04-0.37). CONCLUSION: We describe a readily available score with simple criteria and good diagnostic performance that could be used to screen patients for ferroportin disease in routine clinical practice. LAY SUMMARY: Increased iron burden associated with metabolic syndrome is a very common condition. Ferroportin disease is a dominant genetic iron overload disorder whose prevalence is higher than initially thought. They can be difficult to distinguish from each other, but the limited availability of genetic testing and the lack of definitive guidelines prevent adequate screening. We herein describe a simple and definitive clinical score to help clinicians decide whether to perform genetic testing.

The effects of folate and iron deficiency followed by supplementation on blood morphology and inflammation biomarkers in rats.

BACKGROUND: Little is known about the relation between iron and folic acid (FA) supplementation and inflammation. The aim of this study was to evaluate the effects of iron and folate deficiency and supplementation on blood morphology parameters, and to assess the role of iron and folate transporters in inflammation. METHODS: A four-week period of FA and iron deficiency in Wistar rats was followed by randomization into a group fed with a diet deficient in FA and supplemented with Fe (DFE), a group fed a diet deficient in Fe and supplemented with FA (DFOL), a group fed a diet supplemented with Fe and FA (FEFOL), a group fed a diet deficient in Fe and FA (D), and a group fed a control diet (C). The blood Crp concentration and blood count were determined. The expression of SLC11A2, SLC46A1, SLC19A1, and TFR2 proteins was assessed using the western blot method. RESULTS: After ten days on the experimental diets, the rats in the DFOL group had a 21% higher concentration of white blood cells (WBC) than the FEFOL group did (p < 0.05). We did not observe any differences between the groups in terms of C-reactive protein (Crp) concentration. We also did not find any other differences between the groups in other morphological parameters. Analysis of the correlation between blood count parameters and the expression of iron and folate transporters gave conflicting results. CONCLUSIONS: To conclude, iron and folate supplementation may affect WBC concentration in the blood.

Type 4B hereditary hemochromatosis due to heterozygous p.D157A mutation in SLC40A1 complicated with hypopituitarism.

Hemochromatosis is a clinical syndrome characterized by iron overload in various organs. We present here a case of type 4 hereditary hemochromatosis due to heterozygous mutation in SLC40A1 gene (p.D157A). SLC40A1 encodes ferroportin, a macromolecule only known as iron exporter from mammalian cells. He first presented symptoms correlated with hypopituitarism. Furthermore, marked hyperferritinemia and high transferrin saturation were revealed in combination with the findings of iron overload in the liver, spleen and pituitary gland by computed tomography and magnetic resonance imaging. Liver biopsy revealed iron deposition in both hepatocytes and Kupffer cells. SLC40A1 mutations are considered to cause wide heterogeneity by various ferroportin mutations. Thus, clinicopathological examinations seem to be very important for diagnosing phenotype of type 4 hemochromatosis in addition to the gene analysis. We diagnosed him as type 4B hereditary hemochromatosis (ferroportin-associated hemochromatosis) by the findings of high transferrin saturation and iron deposition in hepatocytes, and then started iron chelating treatment. We should suspect the possibility of hereditary hemochromatosis even in Japanese with severe iron overload. Although the same mutation in SLC40A1 gene (p.D157A) had been reported to cause "loss of function" phenotype, we considered that the mutation of our case caused "gain of function" phenotype.

Association between Consumption of Cow's Milk and Iron Deficiency Anemia in Children: Are There Roles for Hepcidin-25/Ferroportin? A Case-Control Study.

Systemic iron homeostasis is regulated by the interaction of the peptide hormone, hepcidin and the iron exporter, ferroportin. The objective was to investigate the relationship between the consumption of cow's milk and iron deficiency anemia in children 2-10 years old and its association with the hepcidin-25 and ferroportin concentrations. The study population consisted of 187 prepubescent children of similar ideal body weight (IBW:90-120%); 82 children with iron deficiency anemia (37girls and 45boys; 4.27 ± 0.28 years) and 105 (47girls and 58boys; 4.25 ± 0.34 years) healthy age-sex-matched controls. Serum fasting hepcidin-25/ferroportin concentrations were measured by enzyme immunoassay in all subjects. Mean cow's milk consumption in the anemic group (373 ± 248 mL/d) tended to be higher than that in the control group (320 ± 226 mL/d), but the result was not statistically significant (p = 0.063).The mean hepcidin-25 level was significantly higher in the anemic group (19.5 ± 18.4 ng/mL) than in the healthy controls (11.0 ± 10.7, p < 0.001). The mean ferroportin level was lower in the anemic group (21.04 ± 5.74 ng/mL) than in the healthy controls (22.68 ± 4.77 ng/ml, p = 0.037). Consuming cow's milk was not associated with IDA in prepubertal children, provided that it was adequately supplemented with iron-enriched foods. We observed a significant increase in hepcidin-25 levels and a decrease in ferroportin levels in children with iron deficiency anemia compared with healthy controls. Children who consumed more cow's milk had higher levels of hepcidin-25. Iron deficiency anemia is not a concern when cow's milk is given to children if the complementary foods are rich in iron.

SNPs rs11240569, rs708727, and rs823156 in SLC41A1 Do Not Discriminate Between Slovak Patients with Idiopathic Parkinson's Disease and Healthy Controls: Statistics and Machine-Learning Evidence.

Gene SLC41A1 (A1) is localized within Parkinson's disease-(PD)-susceptibility locus PARK16 and encodes for the Na+/Mg2+-exchanger. The association of several A1 SNPs with PD has been studied. Two, rs11240569 and rs823156, have been associated with reduced PD-susceptibility primarily in Asian populations. Here, we examined the association of rs11240569, rs708727, and rs823156 with PD in the Slovak population and their power to discriminate between PD patients and healthy controls. The study included 150 PD patients and 120 controls. Genotyping was performed with the TaqMan® approach. Data were analyzed by conventional statistics and Random Forest machine-learning (ML) algorithm. Individually, none of the three SNPs is associated with an altered risk for PD-onset in Slovaks. However, a combination of genotypes of SNP-triplet GG(rs11240569)/AG(rs708727)/AA(rs823156) is significantly (p < 0.05) more frequent in the PD (13.3%) than in the control (5%) cohort. ML identified the power of the tested SNPs in isolation or of their singlets (joined), duplets and triplets to discriminate between PD-patients and healthy controls as zero. Our data further substantiate differences between diverse populations regarding the association of A1 polymorphisms with PD-susceptibility. Lack of power of the tested SNPs to discriminate between PD and healthy cases render their clinical/diagnostic relevance in the Slovak population negligible.

Comparative study of alloimmunization against red cell antigens in sickle cell disease & thalassaemia major patients on regular red cell transfusion.

BACKGROUND & OBJECTIVES: : Sickle cell disease (SCD) patients require red cell transfusion during different clinical complications of the disease. Such patients are at a high risk for developing alloantibody against red cell antigens. From India, there are limited data available on alloantibody formation in multiply transfused SCD patients. The present study was thus undertaken to fill up this lacunae by looking at the development of red cell alloantibodies in SCD and ß-thalassaemia patients on regular transfusion. METHODS: : All sickle cell disease patients undergoing red cell transfusion between 2008 and 2016, were included. During this period, a large number of ß-thalassaemia major patients also underwent regular red cell transfusion. These thalassaemia patients were also included to compare the tendency of antibody formation between SCD and ß-thalassaemia major patients. All patients before regular transfusion were regularly assessed for the development of red cell antibody. Red cell antigen, antibody screen crossmatch and antibody identification were done using the standard technique. RESULTS: : A total of 138 patients with SCD aged between 4 and 53 yr (mean 17.6 yr) consisting of 83 males and 55 females (male:female, 1.5:1) along with 333 transfusion-dependent ß-thalassaemia patients were studied. Over the last eight years, 15 patients with SCD and four patients with thalassaemia developed alloantibody (P <0.001). Antibody specificity of their alloantibodies was against Rhc, RhE, Kell, Fya and Fyb only. Sickle cell disease patients with and without alloantibody required on the average 11.8 and 8.6 units of red cell concentrate, respectively (P <0.05). INTERPRETATION & CONCLUSIONS: : About 11 per cent of the transfused sickle cells patients developed alloantibodies. The antibody specificity was restricted to Rh, Kell and Duffy blood group systems. Extended antigen matching involving Rh, Kell and Duffy antigens may prevent alloantibody in such patients.

Extracellular vesicles reveal abnormalities in neuronal iron metabolism in restless legs syndrome.

STUDY OBJECTIVES: Determine abnormalities in levels of iron-management proteins in neuronal origin-enriched extracellular vesicles (nEVs) in restless legs syndrome (RLS). METHODS: We used immunoprecipitation for neuronal marker L1CAM to isolate nEVs from the serum of 20 participants with RLS from a study including magnetic resonance imaging (MRI) determinations of iron deposition in the substantia nigra and hematologic parameters and 28 age- and sex-matched Controls. RESULTS: RLS compared with Control participants showed higher levels of nEV total ferritin but similar levels of transferrin receptor and ferroportin. Western blot analysis showed that heavy- but not light-chain ferritin was increased in nEVs of RLS compared with Control participants. In RLS but not Control participants, nEV total ferritin was positively correlated with systemic iron parameters; the two groups also differed in the relation of nEV total ferritin to MRI measures of iron deposition in substantia nigra. CONCLUSIONS: Given the neuronal origin and diversity of EV cargo, nEVs provide an important platform for exploring the underlying pathophysiology and possible biomarkers of RLS.

The role of hepcidin, GDF15, and mitoferrin-1 in iron metabolism of polycythemia vera and essential thrombocytosis patients

Background/aim: GDF15, hepcidin and mitoferrin-1 (mfrn-1) are proteins involved in systemic iron regulation. There are no studies in the literature demonstrating the serum mfrn-1 levels in polycythemia vera (PV) and essential thrombocythemia (ET) patients. The aim of this study was to investigate GDF15, hepcidin and mfrn-1 levels in PV and ET patients. Materials and methods: Ten PV, 17 ET patients, and 27 healthy controls (HCs) were enrolled. GDF15, hepcidin and mfrn-1 values were measured with enzyme-linked immunosorbent assay (ELISA). Results: GDF15 levels were higher in the myeloproliferative neoplasm (MPN) group (P = 0.002). Hepcidin levels were not different between MPN patients and HCs. The mfrn-1 levels were lower in MPN patients (P = 0.039). Hepcidin, GDF15, and mfrn-1 levels were not different between PV and ET patients. mfrn-1 levels were lower in ET patients than HCs (P = 0.038). Conclusion: Increased erythropoiesis in MPNs may lead to high GDF15 levels in these patients. However, hepcidin was not suppressed despite the increased GDF15 levels and erythropoiesis in these patients. Decrease in mfrn-1 in MPNs can be the result of its increased turnover due to increased myelopoiesis. It can be hypothesized that similar hepcidin levels in patients and controls and low mfrn-1 levels in patients may be a defense mechanism against erythroid activity and thromboembolic complications.

Ferroportin-Hepcidin Axis in Prepubertal Obese Children with Sufficient Daily Iron Intake.

Iron metabolism may be disrupted in obesity, therefore, the present study assessed the iron status, especially ferroportin and hepcidin concentrations, as well as associations between the ferroportin-hepcidin axis and other iron markers in prepubertal obese children. The following were determined: serum ferroportin, hepcidin, ferritin, soluble transferrin receptor (sTfR), iron concentrations and values of hematological parameters as well as the daily dietary intake in 40 obese and 40 normal-weight children. The ferroportin/hepcidin and ferritin/hepcidin ratios were almost two-fold lower in obese children (p = 0.001; p = 0.026, respectively). Similar iron concentrations (13.2 vs. 15.2 µmol/L, p = 0.324), the sTfR/ferritin index (0.033 vs. 0.041, p = 0.384) and values of hematological parameters were found in obese and control groups, respectively. Iron daily intake in the obese children examined was consistent with recommendations. In this group, the ferroportin/hepcidin ratio positively correlated with energy intake (p = 0.012), dietary iron (p = 0.003) and vitamin B12 (p = 0.024). In the multivariate regression model an association between the ferroportin/hepcidin ratio and the sTfR/ferritin index in obese children (ß = 0.399, p = 0.017) was found. These associations did not exist in the controls. The results obtained suggest that in obese children with sufficient iron intake, the altered ferroportin-hepcidin axis may occur without signs of iron deficiency or iron deficiency anemia. The role of other micronutrients, besides dietary iron, may also be considered in the iron status of these children.

Efficacy of Lactoferrin Oral Administration in the Treatment of Anemia and Anemia of Inflammation in Pregnant and Non-pregnant Women: An Interventional Study.

The discovery of the ferroportin-hepcidin complex has led to a critical review on the treatment of anemia and anemia of inflammation (AI). Ferroportin, the only known mammalian iron exporter from cells to blood, is negatively regulated by hepcidin, a hormone peptide able to bind to ferroportin, leading to its degradation. Therefore, new efficient therapeutic interventions acting on hepcidin and ferroportin are imperative to manage anemia and AI. Bovine milk derivative lactoferrin (bLf), a glycoprotein able to chelate two ferric ions per molecule, is emerging as a natural anti-inflammatory substance able to modulate hepcidin and ferroportin synthesis through the down-regulation of interleukin-6 (IL-6). Here, an interventional study (ClinicalTrials.gov Identifier: NCT01221844) was conducted by orally administering 100 mg of 20-30% iron-saturated bLf (corresponding to 70-84 µg of elemental iron) twice a day. This treatment was compared with the Italian standard therapy, consisting in the oral administration of 329.7 mg of ferrous sulfate once a day (corresponding to 105 mg of elemental iron). Treatments were carried out on 29 anemic women with minor ß-thalassemia (20 pregnant and 9 non-pregnant), 149 women with hereditary thrombophilia (HT) (70 pregnant and 79 non-pregnant) affected by AI and 20 anemic pregnant women suffering from various pathologies. In anemic pregnant and non-pregnant women with minor ß-thalassemia, presenting undetectable hepcidin levels, differently from ferrous sulfate management, bLf decreased IL-6 (from 25 ± 8 to 6 ± 3 pg/ml) and increased total serum iron (TSI) (from 54 ± 17 to 80 ± 9 µg/dl). BLf was also more efficient than ferrous sulfate in AI treatment in HT pregnant and non-pregnant women by decreasing both serum IL-6 (from 89 ± 8 to 58 ± 6 pg/ml) and hepcidin (from 115 ± 23 to 65 ± 10 ng/ml), thus increasing hematological parameters, such as the number of red blood cells (RBCs), the concentration of hemoglobin, TSI and serum ferritin. BLf was also efficient in treating anemia in other pathological pregnancies. Taken together all the results, bLf, showing a greater benefit and efficacy than the standard ferrous sulfate management, can be considered as a promising compound in treating anemia and AI through its ability to down-regulate IL-6, thus restoring ferroportin-mediated iron export from cells to blood in a hepcidin-dependent or independent way.

Exosomal zinc transporter ZIP4 promotes cancer growth and is a novel diagnostic biomarker for pancreatic cancer.

Pancreatic cancer is one of the deadliest cancers with rapid disease progression. Further elucidation of its underlying molecular mechanisms and novel biomarkers for early detection is necessary. Exosomes are small extracellular vesicles that are released by multiple cell types acting as message carriers during intercellular communication and are promising biomarker candidates. However, the role of pancreatic cancer cell-derived exosomes in cancer progression and the application of these vesicles as novel diagnostic biomarkers have not been fully studied. In this study, we found that PC-1.0 (a highly malignant pancreatic cell line) cell-derived exosomes could be taken up by and enhance PC-1 (a moderately malignant pancreatic cell line) cell proliferation, migration and invasion abilities. We identified ZIP4 as the most upregulated exosomal protein in PC-1.0 cells from our proteomic analysis. In vitro and in vivo (a subcutaneous BALB/c nude mouse model) studies showed that exosomal ZIP4 can significantly promote pancreatic cancer growth. Using clinical blood samples, we compared the diagnostic values of serum exosomal ZIP4 levels between malignant pancreatic cancer patients (n = 24) and benign pancreatic disease patients (n = 32, AUC = .89), and between biliary disease patients (n = 32, AUC = .8112) and healthy controls (n = 46, AUC = .8931). In conclusion, exosomal ZIP4 promotes cancer growth and is a novel diagnostic biomarker for pancreatic cancer.

The interrelationship between hepcidin, vitamin D, and anemia in children with acute infectious disease.

BACKGROUND: Hepcidin is a master regulator of iron metabolism. Recently, it has been shown that vitamin D suppresses hepcidin expression. Our hypothesis was that hepcidin levels inversely correlate with vitamin D levels in anemic children during acute infection. METHODS: A prospective study was performed on 90 patients (45 females, 45 males, mean age 7.3 ± 5 years) who were admitted to the pediatric ward. Sixty-two patients had infectious disease (32 with coexisting anemia, 30 without anemia), and 28 patients were hospitalized for noninfectious causes. Blood samples for IL-6, hepcidin, iron status parameters, and 25-hydroxyvitamin D (25-OHD) were obtained within 72 h after admission. RESULTS: Serum concentrations of IL-6 and hepcidin were significantly higher and 25-OHD, iron, and transferrin were significantly lower in anemic children with infectious disease compared with controls. Children with a serum 25-OHD level < 20 ng/ml had significantly increased odds of having anemia than those with a level > 20 ng/ml (OR: 6.1, CI: 1.15-32.76). Correlation analyses found positive associations between hepcidin levels and ferritin (R2 = 0.47, P < 0.001) and negative associations between hepcidin and transferrin (R2 = 0.57, P < 0.001). CONCLUSION: Higher IL-6 and lower 25-OHD levels may lead to higher hepcidin levels and subsequently to hypoferremia and anemia in children with acute infection.

The dynamics of hepcidin-ferroportin internalization and consequences of a novel ferroportin disease mutation.

The hepcidin-ferroportin axis underlies the pathophysiology of many iron-associated disorders and is a key target for the development of therapeutics for treating iron-associated disorders. The aims of this study were to investigate the dynamics of hepcidin-mediated ferroportin internalization and the consequences of a novel disease-causing mutation on ferroportin function. Specific reagents for ferroportin are limited; we developed and characterized antibodies against the largest extracellular loop of ferroportin and developed a novel cell-based assay for studying hepcidin-ferroportin function. We show that hepcidin-mediated ferroportin internalization is a rapid process and could be induced using low concentrations of hepcidin. Targeted next-generation sequencing utilizing an iron metabolism gene panel developed in our group identified a novel ferroportin p.D84E variant in a patient with iron overload. Wild-type and mutant ferroportin constructs were generated, transfected into HEK293 cells and analysed using an all-in-one flow-cytometry-based assay to study the effects on hepcidin-mediated internalization and iron transport. Consistent with the classical phenotype of ferroportin disease, the p.D84E mutation results in an inability to transport iron and hepcidin insensitivity. These results validate a recently proposed 3D-structural model of ferroportin and highlight the significance of this variant in the structure and function of ferroportin. Our novel ferroportin antibody and assay will be valuable tools for investigating the regulation of hepcidin/ferroportin function and the development of novel approaches for the therapeutic modulation of iron homeostasis.

Whole blood Fe isotopic signature in a sub-Saharan African population.

The Fe isotopic composition of an individual's whole blood has recently been shown to be an interesting clinical indicator of Fe status. The present study aimed to evaluate the influence of several endemic characteristics of a representative population of the South Kivu province, an Fe-rich volcanic African region, on the whole blood Fe isotopic composition. Both diabetes mellitus and the ferroportin Q248H mutation are very common in Africa and are strongly associated with impairments in Fe metabolism. Fe isotopic analysis of whole blood samples was carried out using multi-collector inductively coupled plasma-mass spectrometry (after chromatographic isolation of the target element). Forty-two male subjects (between 48 and 59 years old) living in Bukavu (South Kivu) were enrolled in this study. Among the selected population, wild-type subjects and subjects presenting the ferroportin Q248H mutation (heterozygotes and homozygotes) were included. Within each group, diabetic and non-diabetic patients were considered. The whole blood δ56Fe value ranged from -3.09‰ to -2.41‰. The δ56Fe value shows a significant negative correlation with the ferritin concentration. No correlation could be established between the whole blood δ56Fe value and the transferrin concentration, transferrin saturation or serum Fe concentration. The ferroportin Q248H mutation did not seem to have affected the whole blood Fe isotopic signature. The whole blood δ56Fe values were significantly higher in diabetic subjects than in non-diabetic subjects and showed a significant negative correlation with body mass index (BMI) values.

Regulation of the Iron Homeostatic Hormone Hepcidin.

Iron is required for many biological processes but is also toxic in excess; thus, body iron balance is maintained through sophisticated regulatory mechanisms. The lack of a regulated iron excretory mechanism means that body iron balance is controlled at the level of absorption from the diet. Iron absorption is regulated by the hepatic peptide hormone hepcidin. Hepcidin also controls iron release from cells that recycle or store iron, thus regulating plasma iron concentrations. Hepcidin exerts its effects through its receptor, the cellular iron exporter ferroportin. Important regulators of hepcidin, and therefore of systemic iron homeostasis, include plasma iron concentrations, body iron stores, infection and inflammation, and erythropoiesis. Disturbances in the regulation of hepcidin contribute to the pathogenesis of many iron disorders: hepcidin deficiency causes iron overload in hereditary hemochromatosis and nontransfused ß-thalassemia, whereas overproduction of hepcidin is associated with iron-restricted anemias seen in patients with chronic kidney disease, chronic inflammatory diseases, some cancers, and inherited iron-refractory iron deficiency anemia. This review summarizes our current understanding of the molecular mechanisms and signaling pathways involved in the control of hepcidin synthesis in the liver, a principal determinant of plasma hepcidin concentrations.

Intestinal expression of genes implicated in iron absorption and their regulation by hepcidin.

BACKGROUND & AIMS: Through inhibition of iron absorption and iron mobilization from tissue stores, hepcidin exerts a negative control on iron homeostasis. Hepcidin, in fact, promotes the degradation of ferroportin (Fpn1), the iron exporter molecule expressed on the membrane of hepatocytes and macrophages, thus preventing iron release from cells to plasma. Hepcidin effects on enterocytes, however, are less clear. Aim of the present study was to further investigate the regulation of iron absorption by hepcidin. METHODS: The transcriptional response of human duodenal mucosa to hepcidin was investigated using organ cultures of duodenal biopsies perendoscopically collected from healthy controls. Biopsies were cultured for 4 h with or without hepcidin-25 and were then assayed for the expression of iron-related genes. RESULTS: In samples that had not been exposed to hepcidin, correlations were found between the expression of genes involved in iron absorption: DMT1, Fpn1, Dcytb and HCP1. In ex vivo experiments hepcidin down-regulated mRNA levels of the iron transporters Fpn1, and DMT1, of the ferric reductase Dcytb, of the ferroxidase hephaestin, and of the putative heme carrier protein HCP1. CONCLUSIONS: Through the reported transcriptional changes hepcidin can modulate several steps of the iron absorption process, including the reduction of dietary iron by Dcytb, its uptake by enterocytes through DMT1, the mucosal uptake of heme iron by HCP1, and enterocyte iron release to plasma by Fpn1 in conjunction with hephaestin.

Quantification of ATP7B Protein in Dried Blood Spots by Peptide Immuno-SRM as a Potential Screen for Wilson's Disease.

Wilson's Disease (WD), a copper transport disorder caused by a genetic defect in the ATP7B gene, has been a long time strong candidate for newborn screening (NBS), since early interventions can give better results by preventing irreversible neurological disability or liver cirrhosis. Several previous pilot studies measuring ceruloplasmin (CP) in infants or children showed that this marker alone was insufficient to meet the universal screening for WD. WD results from mutations that cause absent or markedly diminished levels of ATP7B. Therefore, ATP7B could serve as a marker for the screening of WD, if the protein can be detected from dried blood spots (DBS). This study demonstrates that the immuno-SRM platform can quantify ATP7B in DBS in the picomolar range, and that the assay readily distinguishes affected cases from normal controls (p < 0.0001). The assay precision was <10% CV, and the protein was stable for a week in DBS at room temperature. These promising proof-of-concept data open up the possibility of screening WD in newborns and the potential for a multiplexed assay for screening a variety of congenital disorders using proteins as biomarkers in DBS.

A moderate increase in dietary zinc reduces DNA strand breaks in leukocytes and alters plasma proteins without changing plasma zinc concentrations.

BACKGROUND: Food fortification has been recommended to improve a population's micronutrient status. Biofortification techniques modestly elevate the zinc content of cereals, but few studies have reported a positive impact on functional indicators of zinc status. OBJECTIVE: We determined the impact of a modest increase in dietary zinc that was similar to that provided by biofortification programs on whole-body and cellular indicators of zinc status. DESIGN: Eighteen men participated in a 6-wk controlled consumption study of a low-zinc, rice-based diet. The diet contained 6 mg Zn/d for 2 wk and was followed by 10 mg Zn/d for 4 wk. To reduce zinc absorption, phytate was added to the diet during the initial period. Indicators of zinc homeostasis, including total absorbed zinc (TAZ), the exchangeable zinc pool (EZP), plasma and cellular zinc concentrations, zinc transporter gene expression, and other metabolic indicators (i.e., DNA damage, inflammation, and oxidative stress), were measured before and after each dietary-zinc period. RESULTS: TAZ increased with increased dietary zinc, but plasma zinc concentrations and EZP size were unchanged. Erythrocyte and leukocyte zinc concentrations and zinc transporter expressions were not altered. However, leukocyte DNA strand breaks decreased with increased dietary zinc, and the level of proteins involved in DNA repair and antioxidant and immune functions were restored after the dietary-zinc increase. CONCLUSIONS: A moderate 4-mg/d increase in dietary zinc, similar to that which would be expected from zinc-biofortified crops, improves zinc absorption but does not alter plasma zinc. The repair of DNA strand breaks improves, as do serum protein concentrations that are associated with the DNA repair process. This trial was registered at clinicaltrials.gov as NCT02861352.

Clinical presentations of Wilson disease among Polish children.

INTRODUCTION: Wilson disease (WD) may present from early childhood up to the eighth decade, presenting with variable hepatic and neuropsychiatric symptoms. Establishing the diagnosis is straightforward if the major clinical and laboratory features are present. However, clinical phenotypes are highly varied and early, proper diagnosis can be challenging. AIM: The aim of our study was to analyze clinical presentations and diagnostic tests of Polish pediatric patients with WD. METHODS: We retrospectively analyzed medical history of 156 patients with confirmed diagnosis of WD treated at our Institute from 1996 till March 2016. RESULTS: The mean age at onset of symptoms was 10.15±4.23 years of age. Hepatic presentation was the most common one (94.23%) with either liver failure (16.03%) or more frequently increased transaminases (78.2%). In 90.26% cases ceruloplasmin serum concentration was ≤0,2 g/l, in 51.93% patients basal urinary copper excretion was >100 µg/24 h. Mutation analysis was performed in 155 (99.36%) cases. The most common mutation was p.H1069Q. CONCLUSIONS: Wilson disease can present with only significantly increased transaminases activity and hepatomegaly or liver failure, but neurological symptoms are very rare in children. Diagnostic approach is challenging due to wide spectrum of clinical presentations in a high variable degree of severity. Genetic screening is supportive, ceruloplasmin and urinary copper excretion are valuable tests in the majority of patients but do not allow to exclude WD.