Hepcidin analysis in pneumonia: Comparison of immunoassay and LC-MS/MS.

BACKGROUND: The iron-regulatory hormone hepcidin is a promising biomarker to differentiate anaemia of inflammation from iron deficiency. Plasma hepcidin concentrations increase substantially during inflammation, and the amount of smaller, non-biologically active isoforms of hepcidin increase in inflammatory conditions. These smaller isoforms are measured in some, but not all analytical methods. Thus, we evaluated the comparability of two analytical methods with different isoform selectivity during and after acute-phase pneumonia as a highly inflammatory model disease. METHODS: Blood samples from a cohort of 267 hospitalized community-acquired pneumonia patients collected at admission and a 6-week follow-up were analysed. Hepcidin was measured in plasma by an immunoassay, which recognizes all hepcidin isoforms, and a liquid chromatography tandem mass spectrometry (LC-MS/MS), which selectively measures the bioactive hepcidin-25. Additionally, a subset of serum samples was analysed by LC-MS/MS. RESULTS: Hepcidin measurements by immunoassay were higher compared with LC-MS/MS. The relative mean difference of hepcidin plasma concentrations between the two analytical methods was larger in admission samples than in follow-up samples (admission samples <200 ng/mL: 37%, admission samples >200 ng/mL: 78%, follow-up samples >10 ng/mL: 22%). During acute-phase pneumonia, serum concentrations were on average 22% lower than plasma concentrations when measured by LC-MS/MS. CONCLUSIONS: Immunoassay measured higher hepcidin concentrations compared with LC-MS/MS, with more pronounced differences in high-concentration samples during acute-phase pneumonia. These findings should be considered in local method validations and in future harmonization and standardization optimization of hepcidin measurements.

Impact of treating iron deficiency, diagnosed according to hepcidin quantification, on outcomes after a prolonged ICU stay compared to standard care: a multicenter, randomized, single-blinded trial.

BACKGROUND: Anemia is a significant problem in patients on ICU. Its commonest cause, iron deficiency (ID), is difficult to diagnose in the context of inflammation. Hepcidin is a new marker of ID. We aimed to assess whether hepcidin levels would accurately guide treatment of ID in critically ill anemic patients after a prolonged ICU stay and affect the post-ICU outcomes. METHODS: In a controlled, single-blinded, multicenter study, anemic (WHO definition) critically ill patients with an ICU stay ≥ 5 days were randomized when discharge was expected to either intervention by hepcidin treatment protocol or control. In the intervention arm, patients were treated with intravenous iron (1 g of ferric carboxymaltose) when hepcidin was < 20 µg/l and with intravenous iron and erythropoietin for 20 ≤ hepcidin < 41 µg/l. Control patients were treated according to standard care (hepcidin quantification remained blinded). Primary endpoint was the number of days spent in hospital 90 days after ICU discharge (post-ICU LOS). Secondary endpoints were day 15 anemia, day 30 fatigue, day 90 mortality and 1-year survival. RESULTS: Of 405 randomized patients, 399 were analyzed (201 in intervention and 198 in control arm). A total of 220 patients (55%) had ID at discharge (i.e., a hepcidin < 41 µg/l). Primary endpoint was not different (medians (IQR) post-ICU LOS 33(13;90) vs. 33(11;90) days for intervention and control, respectively, median difference - 1(- 3;1) days, p = 0.78). D90 mortality was significantly lower in intervention arm (16(8%) vs 33(16.6%) deaths, absolute risk difference - 8.7 (- 15.1 to - 2.3)%, p = 0.008, OR 95% IC, 0.46, 0.22-0.94, p = 0.035), and one-year survival was improved (p = 0.04). CONCLUSION: Treatment of ID diagnosed according to hepcidin levels did not reduce the post-ICU LOS, but was associated with a significant reduction in D90 mortality and with improved 1-year survival in critically ill patients about to be discharged after a prolonged stay. TRIAL REGISTRATION: www.clinicaltrial.gov NCT02276690 (October 28, 2014; retrospectively registered).

Clinical Immunoassay for Human Hepcidin Predicts Iron Deficiency in First-Time Blood Donors.

BACKGROUND: Serum markers currently used as indicators of iron status have clinical limitations. Hepcidin, a key regulator of iron homeostasis, is reduced in iron deficiency (ID) and increased in iron overload. We describe the first CLIA-validated immunoassay with excellent accuracy and precision to quantify human serum hepcidin. Its diagnostic utility for detecting ID in first-time blood donors was demonstrated. METHODS: A monoclonal competitive ELISA (C-ELISA) was developed for the quantitation of human hepcidin and validated according to CLIA guidelines. Sera from nonanemic first-time blood donors (n = 292) were analyzed for hepcidin, ferritin, transferrin, and serum iron. Logistic regression served to determine the utility of hepcidin as a predictor of ID. RESULTS: The C-ELISA was specific for human hepcidin and had a low limit of quantitation (4.0 ng/mL). The hepcidin concentration measured with the monoclonal C-ELISA was strongly correlated with a previously established, extensively tested polyclonal C-ELISA (Blood 2008;112:4292-7) (r = 0.95, P < 0.001). The area under the receiver operating characteristic curve for hepcidin as a predictor of ID, defined by 3 ferritin concentration thresholds, was >0.9. For predicting ID defined by ferritin <15 ng/mL, hepcidin <10 ng/mL yielded sensitivity of 93.1% and specificity of 85.5%, whereas the same hepcidin cutoff for ferritin <30 ng/mL yielded sensitivity of 67.6% and specificity of 91.7%. CONCLUSION: The clinical measurement of serum hepcidin concentrations was shown to be a potentially useful tool for diagnosing ID.

Immunoreactivities for hepcidin, ferroportin, and hephaestin in astrocytes and choroid plexus epithelium of human brains.

Iron plays essential roles in the central nervous system. However, how the iron level is regulated in brain cells including glia and neurons remains to be fully clarified. In this study, the localizations of hepcidin, ferroportin, and hephaestin, which are known to be involved in iron efflux, were immunohistochemically examined in autopsied human brains. Immunoreactivities for hepcidin and ferroportin were observed in granular structures within the cytoplasm of reactive astrocytes and epithelial cells of the choroid plexus. Granular structures showing immunoreactivities for hepcidin and ferroportin were also stained with antibodies for early endosome antigen 1 (EEA1). In addition, immunoreactivity for hephaestin was observed in the cytoplasm of epithelial cells of the choroid plexus as well as reactive astrocytes. Immunoreactivity for hephaestin in the cytoplasm of reactive astrocytes was occasionally colocalized with immunoreactivity for EEA1, while that of hephaestin was frequently observed in the cytoplasm showing no immunoreactivity for EEA1. These findings suggest that immunoreactivities for hepcidin and ferroportin are localized in close proximity to granular structures showing immunoreactivity for EEA1 in the cytoplasm of human brain astrocytes. They also suggest that immunoreactivity of hephaestin is localized in the cytoplasm of the choroid plexus epithelium as well as reactive astrocytes of human brains.

A Targeted Mass Spectrometric Assay for Reliable Sensitive Hepcidin Quantification.

Hepcidin, a cysteine-rich peptide hormone, secreted mainly by the liver, plays a central role in iron metabolism regulation. Emerging evidence suggests that disordered iron metabolism is a risk factor for various types of diseases including cancers. However, it remains challenging to apply current mass spectrometry (MS)-based hepcidin assays for precise quantification due to the low fragmentation efficiency of intact hepcidin as well as synthesis difficulties for the intact hepcidin standard. To address these issues we recently developed a reliable sensitive targeted MS assay for hepcidin quantification from clinical samples that uses fully alkylated rather than intact hepcidin as the internal standard. Limits of detection and quantification were determined to be <0.5 ng/mL and 1 ng/mL, respectively. Application of the alkylated hepcidin assay to 70 clinical plasma samples (42 non-cancerous and 28 ovarian cancer patient samples) enabled reliable detection of endogenous hepcidin from the plasma samples, as well as conditioned culture media. The hepcidin concentrations ranged from 0.0 to 95.6 ng/mL across non-cancerous and cancer plasma specimens. Interestingly, cancer patients were found to have significantly higher hepcidin concentrations compared to non-cancerous patients (mean: 20.6 ng/ml for cancer; 5.94 ng/ml for non-cancerous) (p value < 0.001). Our results represent the first application of the alkylated hepcidin assay to clinical samples and demonstrate that the developed assay has better sensitivity and quantification accuracy than current MS-based hepcidin assays without the challenges in synthesis of intact hepcidin standard and accurately determining its absolute amount.

Safety and efficacy of sucrosomial iron in inflammatory bowel disease patients with iron deficiency anemia.

Iron deficiency anemia (IDA) is one of the most common complications of inflammatory bowel disease (IBD). We planned a prospective study to address tolerability and efficacy of sucrosomial iron, a new oral formulation of ferric pyrophosphate, in IBD patients. Thirty patients with a confirmed diagnosis of Crohn's Disease (CD) or ulcerative colitis (UC) and mild IDA were enrolled. Patients with severe IBD were excluded. All patients underwent 12 weeks of oral treatment with 30 mg/day of sucrosomial iron. Treatment compliance and adverse events were investigated every 4 weeks. Iron status, hematological parameters and IBD activity scores were determined at baseline and at the end of treatment, as well as serum hepcidin and non-transferrin bound iron (NTBI) levels. Twenty-four (80%) patients took more than 90% of the prescribed regimen. Forty-four adverse events (AEs) were recorded, but none of them is considered certainly or probably related to the study treatment. Interestingly, only eleven gastrointestinal events were recorded in 9 (30%) patients. At the end of treatment, all iron parameters improved significantly and Hb increased in 86% of patients (from 11.67 to 12.37 g/dl, p = 0.001). Serum hepcidin showed a significant increase in 79% of patients and became positively correlated with C-reactive protein (CRP) at the end of the study, while NTBI remained below the detection threshold after iron supplementation. The IBD activity scores improved in both CD and UC. This pilot interventional study supports the therapeutic use of sucrosomial iron in IBD and paves the way for future studies in larger or more difficult IBD populations.

Iron deficiency diagnosed using hepcidin on critical care discharge is an independent risk factor for death and poor quality of life at one year: an observational prospective study on 1161 patients.

BACKGROUND: Iron deficiency is difficult to diagnose in critically ill patients, but may be frequent and may impair recovery. Measurement of hepcidin could help in the diagnosis of iron deficiency. We aim to assess if iron deficiency diagnosed using hepcidin is associated with poorer outcome one year after an intensive care unit stay. METHODS: We used the prospective FROG-ICU, multicentre (n = 28 ICUs), observational cohort study of critically ill survivors followed up one year after intensive care unit discharge. Iron deficiency was defined as hepcidin < 20 ng/l, ferritin < 100 ng/l or soluble transferrin receptor (sTfR)/log(ferritin) > 0.8, measured in blood drawn at intensive care unit discharge. Main outcomes were one-year all-cause mortality and poor quality of life (defined as a Short Form 36 (SF-36) score below the median). RESULTS: Among the 2087 patients in the FROG-ICU cohort, 1570 were discharged alive and 1161 had a blood sample available at intensive care unit discharge and were included in the analysis. Using hepcidin, 429 (37%) patients had iron deficiency, compared to 72 (6%) using ferritin alone and 151 (13%) using the sTfR/log(ferritin) ratio. Iron deficiency diagnosed according to low hepcidin was an independent predictor of one-year mortality (OR 1.51 (1.10-2.08)) as was high sTfR/log ferritin ratio (OR = 1.95 (1.27-3.00)), but low ferritin was not. Severe ID, defined as hepcidin < 10 ng/l, was also an independent predictor of poor one-year physical recovery (1.58 (1.01-2.49)). CONCLUSIONS: Iron deficiency, diagnosed using hepcidin, is very frequent at intensive care unit discharge and is associated with increased one-year mortality and poorer physical recovery. Whether iron treatment may improve these outcomes remains to be investigated.

Hepcidin: immunoanalytic characteristics.

Hepcidin has progressively become essential in clinical practice for the diagnosis and follow-up of a large spectrum of diseases. Anyway, its own biochemical and structural characteristics have complicated and delayed the acquisition of a standardized quantifying tool of the peptide.

Hepcidin as a potential predictor for preoperative anemia treatment with intravenous iron-A retrospective pilot study.

Preoperative anemia occurs in about one third of patients who undergo elective surgery and is associated with an impaired outcome. Therefore, screening of preoperative anemia was established in the context of a multidisciplinary Patient Blood Management (PBM) program at the University Hospital of Muenster, Germany. Anemic patients without contraindications were treated with intravenous (IV) iron (ferric carboxymaltose) to increase their hemoglobin (Hgb) levels and hence to treat anemia prior to surgery. Interestingly, we detected a large variability in the response of Hgb levels after IV iron administration. Systemic iron homeostasis is mainly regulated by the hepatic hormone hepcidin, which regulates the cell surface expression of the sole known iron exporter ferroportin. The objective of this retrospective pilot study was to analyze the potential of hepcidin to predict the response of anemic patients to preoperative IV iron treatment measured as increase in Hgb. Serum samples of non-anemic (n = 48), untreated anemic (n = 64) and anemic patients treated with IV iron (n = 79), in total 191 patients, were collected between October 2014 until June 2016. Serum hepcidin levels were determined and data were analyzed retrospectively. The analysis revealed at first a correlation between serum hepcidin levels and the parameters of the iron status. Second, patients treated with IV iron showed a noticeably higher increase in their delta Hgb level between PBM consultation and surgery (0.45g/dl [0.05, 1.05] compared to patients without IV iron (0.1g/dl [-0.48, 0.73], *p = 0.03). Patients were then grouped into 'non-responders', defined as delta Hgb <0.6g/dl and 'responders', with delta Hgb ≥0.6g/dl between the day of IV iron treatment and the day of surgery. Within normal ranges and clinically unapparent, a statistically noticeable difference between responders and non-responders was found for CRP and leukocytes. Serum hepcidin levels were higher in the group of non-responders (10.6ng/ml [3.93, 34.77]) compared to responders (2.1ng/ml [0.25, 7.97], *p = 0.04). To conclude, the data of this retrospective pilot study indicate that hepcidin might be a promising biomarker to predict a patient`s responsiveness to IV iron in preoperative anemia treatment. Prospective studies have to investigate serum hepcidin levels as a biomarker to guide physician`s decision on IV iron substitution.

Acute and Chronic Iron Overloading Differentially Modulates the Expression of Cellular Iron-homeostatic Molecules in Normal Rat Kidney.

Little is known about the renal responses to acute iron overloading. This study measured the renal tubular expression of transferrin receptor-1 (TfR1), cubilin/megalin receptors, hepcidin, ferroportin, and ferritin chains following subacute intoxication of 40 male Wistar rats with a single oral dose of ferrous iron (300 mg/kg). The animals were randomly subdivided into 4 equal subgroups at the time of necropsy (1, 2, 4, and 8 hr). The results were compared with the controls ( n=15) and with the chronic group ( n=15), which received iron for 4 weeks (75 mg/kg/day; 5 days/week). Although both toxicity models inhibited TfR1, they upregulated the cubilin/megalin receptors and hepcidin, and triggered iron deposition in tubular cells. The ferritin heavy-chain and ferroportin were downregulated in the 2-hr and 4-hr acute subgroups, whereas chronic toxicity promoted their expression, compared with controls. Moreover, the 4-hr and 8-hr subgroups had higher intracellular Fe+2 and marked cell apoptosis compared with the chronic group. In conclusion, the kidney appears to sustain iron reabsorption in both intoxication models. However, the cellular iron storage and exporter proteins were differentially expressed in both models, and their inhibition post-acute toxicity might contribute toward the intracellular accumulation of Fe+2, oxidative stress, and ferroptosis.

Bacteria-Carried Iron Oxide Nanoparticles for Treatment of Anemia.

The efficiency of maghemite nanoparticles for the treatment of anemia was sensibly higher when nanoparticles were incorporated onto the probiotic bacterium Lactobacillus fermentum (MNP-bacteria) than when administrated as uncoated nanoparticles (MNP). Plasma iron and hemoglobin, intestine expression of divalent metal transporter 1 (DMT1) and duodenal Cytochrome b (DcytB), as well as hepatic expression of the hormone hepcidin were fully restored to healthy levels after administration of MNP-bacteria but not of MNP. A magnetic study on biodistribution and biodegradation showed accumulation of maghemite nanoparticles in intestine lumen when MNP-bacteria were administrated. In contrast, MNP barely reached intestine. In vivo MRI studies suggested the internalization of MNP-bacteria into enterocytes, which did not occur with MNP. Transmission electronic microscopy confirmed this internalization. The collective analysis of results point out that L. fermentum is an excellent carrier to overcome the stomach medium and drive maghemite nanoparticles to intestine, where iron absorption occurs. Due the probiotic ability to adhere to the gut wall, MNP-bacteria internalize into the enterocyte, where maghemite nanoparticles are delivered, providing an adequate iron level into enterocyte. This paper advances a new route for effective iron absorption in the treatment of anemia.

Optimizing charge state distribution is a prerequisite for accurate protein biomarker quantification with LC-MS/MS, as illustrated by hepcidin measurement.

BACKGROUND: Targeted quantification of protein biomarkers with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has great potential, but is still in its infancy. Therefore, we elucidated the influence of charge state distribution and matrix effects on accurate quantification, illustrated by the peptide hormone hepcidin. METHODS: An LC-MS/MS assay for hepcidin, developed based on existing literature, was improved by using 5 mM ammonium formate buffer as mobile phase A and as an elution solution for solid phase extraction (SPE) to optimize the charge state distribution. After extensive analytical validation, focusing on interference and matrix effects, the clinical consequence of this method adjustment was studied by performing receiving operating characteristic (ROC)-curve analysis in patients with iron deficiency anemia (IDA, n=44), anemia of chronic disease (ACD, n=42) and non-anemic patients (n=93). RESULTS: By using a buffered solution during sample preparation and chromatography, the most abundant charge state was shifted from 4+ to 3+ and the charge state distribution was strongly stabilized. The matrix effects which occurred in the 4+ state were therefore avoided, eliminating bias in the low concentration range of hepcidin. Consequently, sensitivity, specificity and positive predictive value (PPV) for detection of IDA patients with the optimized assay (96%, 97%, 91%, respectively) were much better than for the original assay (73%, 70%, 44%, respectively). CONCLUSIONS: Fundamental improvements in LC-MS/MS assays greatly impact the accuracy of protein quantification. This is urgently required for improved diagnostic accuracy and clinical value, as illustrated by the validation of our hepcidin assay.

Serum and salivary ferritin and Hepcidin levels in patients with chronic periodontitis and type 2 diabetes mellitus.

BACKGROUND: Iron disorder and abnormal expression of hepcidin play important roles in many diseases, but it is still unclear in chronic periodontitis (CP) and type 2 diabetes mellitus (T2DM). We aimed to assess ferritin and hepcidin levels in serum and saliva of CP patients with or without T2DM. METHODS: Serum and unstimulated whole saliva samples were collected from 88 participants, who were categorized into 4 groups based on the presence or absence of CP or T2DM. Demographics and general health parameters were recorded. Full-mouth clinical periodontal parameters including probing pocket depth, clinical attachment loss, bleeding index, and plaque index were recorded. Chemiluminescence microparticle immunoassay and enzyme-linked immunosorbent assay were used to detect ferritin and hepcidin concentrations, respectively, in serum and saliva. RESULTS: Serum ferritin and hepcidin levels in the CP and CP with T2DM groups were higher than in the control group (P < 0.05). Serum hepcidin and serum ferritin are linear correlated (P < 0.001). Serum hepcidin/ferritin values in the CP with T2DM group were significantly lower than those in the T2DM and control groups. Moreover, salivary ferritin levels in the CP and T2DM groups were higher than those in the control group (P < 0.05). There was positively correlation between salivary ferritin and serum ferritin (P = 0.017). Hepcidin concentrations were relatively low in saliva. CONCLUSIONS: These results suggest that iron overload and hepcidin inadequacy existed in CP with T2DM patients. Salivary ferritin might provide a reference for body iron load. TRIAL REGISTRATION: ChiCTR-ROC-17012780.

Improved LC-MS/MS method for the quantification of hepcidin-25 in clinical samples.

Mass spectrometry-based methods play a crucial role in the quantification of the main iron metabolism regulator hepcidin by singling out the bioactive 25-residue peptide from the other naturally occurring N-truncated isoforms (hepcidin-20, -22, -24), which seem to be inactive in iron homeostasis. However, several difficulties arise in the MS analysis of hepcidin due to the "sticky" character of the peptide and the lack of suitable standards. Here, we propose the use of amino- and fluoro-silanized autosampler vials to reduce hepcidin interaction to laboratory glassware surfaces after testing several types of vials for the preparation of stock solutions and serum samples for isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS). Furthermore, we have investigated two sample preparation strategies and two chromatographic separation conditions with the aim of developing a LC-MS/MS method for the sensitive and reliable quantification of hepcidin-25 in serum samples. A chromatographic separation based on usual acidic mobile phases was compared with a novel approach involving the separation of hepcidin-25 with solvents at high pH containing 0.1% of ammonia. Both methods were applied to clinical samples in an intra-laboratory comparison of two LC-MS/MS methods using the same hepcidin-25 calibrators with good correlation of the results. Finally, we recommend a LC-MS/MS-based quantification method with a dynamic range of 0.5-40 µg/L for the assessment of hepcidin-25 in human serum that uses TFA-based mobile phases and silanized glass vials. Graphical abstract Structure of hepcidin-25 (Protein Data Bank, PDB ID 2KEF).

Hepatic iron is the major determinant of serum ferritin in NAFLD patients.

BACKGROUND AND AIMS: Elevated serum ferritin is common in NAFLD, and is associated with more advanced disease and increased mortality. Hyperferritinaemia in NAFLD is often attributed to inflammation, while in other conditions ferritin closely reflects body iron stores. The aim of this study was to clarify the underlying cause of hyperferritinaemia in NAFLD. METHODS: Ferritin levels were examined with markers of iron status, inflammation and liver injury across the clinical spectrum of NAFLD using blood, tissue and magnetic resonance (MR) imaging. A separate larger group of NAFLD patients with hepatic iron staining and quantification were used for validation. RESULTS: Serum ferritin correlated closely with the iron regulatory hormone hepcidin, and liver iron levels determined by MR. Furthermore, ferritin levels reflected lower serum adiponectin, a marker of insulin resistance, and liver fat, but not cytokine or CRP levels. Ferritin levels differed according to fibrosis stage, increasing from early to moderate disease, and declining in cirrhosis. A similar pattern was found in the validation cohort of NAFLD patients, where ferritin levels were highest in those with macrophage iron deposition. Multivariate analysis revealed liver iron and hepcidin levels as the major determinants of serum ferritin. CONCLUSIONS: While hyperferritinaemia is associated with markers of liver injury and insulin resistance, serum hepcidin and hepatic iron are the strongest predictors of ferritin levels. These findings highlight the role of disordered iron homeostasis in the pathogenesis of NAFLD, suggesting that therapies aimed at correcting iron metabolism may be beneficial.

[Siwu decoction improves iron deficiency anemia in infant rats and regulates iron metabolism].

To investigate the effect of Siwu decoction on improving iron deficiency anemia in infant rats and observe its regulatory effects on iron metabolism. SD rats were fed with low iron fodder for 2 weeks, and then the rats with hemoglobin level less than 75 g•L ⁻¹ were screened out and randomly divided into model group, Ferrous succinate 50 mg•kg ⁻¹ group, Siwu decoction 4 g•kg ⁻¹, 8 g•kg ⁻¹ and 16 g•kg ⁻¹ groups. After 4 weeks' gavage administration, Wright-Giemsa's staining of blood smear and HE staining of the livers were conducted, and all rats were tested for blood routine, serum iron, total iron binding capacity, serum ferritin, serum hepcidin and liver hepcidin. The expression levels of liver ferritin, transferrin and transferrin receptor 1 were also detected. The results showed that as compared with normal group, the activity level of model group was decreased, and the color and lustre of auricles and toes were pale white; the number of red blood cells was decreased; the volume was smaller, with an increased zone of central pallor; the body weight and blood routine parameters were decreased significantly; the livers were pale red, and the hepatic cords around thecentral veins were unclear and misaligned; the serum iron, serum ferritin, liver iron levels and the expression of liver ferritin were decreased significantly; the total iron binding capacity, serum hepcidin, liver hepcidin, the expression levels of liver transferrin and transferrin receptor 1 were significantly increased, indicating successful establishment of models. As compared with the model group, activity was increased in Siwu decoction group; the color and lustre of auricles and toes were ruddy; the number of red blood cells was increased; the volume was larger, with a decreased zone of central pallor; the body weight and blood routine parameters were increased significantly; the livers were red, hepatic cords around the central veins were clear and aligned;the serum iron, serum ferritin, liver iron levels and the expression of liver ferritin were significantly increased, the total iron binding capacity, serum hepcidin, liver hepcidin, the expression of liver transferrin and transferrin receptor 1 were decreased significantly. The results demonstrated that Siwu decoction had a certain effect on improving iron deficiency anemia in infant rats, and the mechanism may be associated with the regulatory effect of hepcidin iron metabolism.

Impact of iron deficiency diagnosis using hepcidin mass spectrometry dosage methods on hospital stay and costs after a prolonged ICU stay: Study protocol for a multicentre, randomised, single-blinded medico-economic trial.

BACKGROUND: Iron deficiency (ID) is frequent but difficult to diagnose in critically ill patients. ID may be responsible for prolonged post-ICU hospital stays, since it results in fatigue, muscle weakness and anaemia. Hepcidin, the key iron metabolism hormone, may be a good marker of ID in these patients. The aim of this study is to determine whether using mass spectrometry hepcidin determination to diagnose (and treat) ID after prolonged ICU stays may reduce patients' subsequent hospital stays and costs in comparison with conventional (ferritin) methods. METHODS: This is a randomised, controlled, single-blinded, multicentre medico-economic study. Hepcidin quantification will be performed in anaemic (WHO criteria) critically ill adults about to be discharged, after a stay ≥5days. In the intervention arm (hepcidin) results will be given to the ICU-physicians, and not in the control arm. ID Treatment will be recommended in intervention arm: IV iron when hepcidin is <20µg/L; IV iron+erythropoietin when hepcidin is between 20-41µg/L; in the control arm: IV iron when ferritin <300µg/L and Transferrin saturation <20%. The primary endpoint will be the number of days spent in hospital 90 days after ICU discharge and the direct hospital costs. Secondary endpoints will be anaemia and iron deficiency on D15, fatigue and the proportion of patients alive and at home on D30 and D90. DISCUSSION: The results of this study will show whether diagnosing iron deficiency using MS hepcidin determination methods is liable to reduce patients' post-ICU hospital stay and costs, as well as their anaemia and fatigue.

Prohepcidina y estado del hierro e inflamación en escolares sanos o H. pylori positivos asintomáticos / Prohepcidine iron status and inflammation in healthy and asymptomatic H. pylori school children / Pró-hepcidina estado de ferro e inflamação em estudantes saudáveis ou H. pylori positivos assintomáticos

El eje hepcidina-ferroportina es determinante en la homeostasis del hierro. Niveles elevados de hepcidina reducen la capacidad de absorción intestinal del hierro, así como su movilización entre tejidos. Una condición que produce valores séricos elevados de hepcidina es la infección. Como la infección con Helicobacter pylori (Hp) predispone a una deficiencia de hierro, en este estudio se evaluaron los niveles séricos de Pro-Hepcidina (PH), un precursor de la hepcidina, en un grupo de escolares asintomáticos, infectados con Hp (80 niños) y se los comparó con un grupo similar de niños sanos (59 niños). Los resultados mostraron que los niños infectados en los que se detectó la presencia de Hp (test de aire espirado) tenían valores de proteína C reactiva (PCR) significativamente más altos que los niños sanos. Ambos grupos presentaron valores similares de: adecuación de la ingesta de hierro, ferritina sérica (Fs), hemoglobina, hematocrito, receptores solubles de transferrina. La prevalencia de anemia y deficiencia subclínica de hierro en el grupo total (infectados + no infectados) fue de 10 y 60%, respectivamente sin diferencias entre los grupos. Sin embargo, en el grupo de niños sanos la PH sérica correlacionó significativamente (r=0,730/p<0,001) con los niveles de Fs, mientras que en los niños infectados, los niveles de PH no correlacionaron con la Fs, pero correlacionaron con la severidad de la infección (r=0,52/p<0,001). Esta tendencia de la PH a aumentar con la severidad de la infección podría explicar la mayor prevalencia de deficiencia de hierro en pacientes infectados con Hp.

The hepcidin-ferroportin axis is crucial in iron homeostasis. High serum hepcidine reduces iron intestinal absorption and tissue iron mobilization. Infection and inflammation increase serum hepcidin, predisposing to iron deficiency. Since Helicobacter pylori (Hp) infection has been associated to iron deficiency, the serum levels of prohepcidin PH (a precursor of hepcidin) were evaluated in 80 school children infected with Hp but without gastric symptoms. This was compared with PH levels in a group of 59 non Hp infected children. The results showed that infected children (exhaled air method) had higher levels of protein C reactive protein (CRP) than the non-infected group. Both groups had similar levels of iron consumption, serum ferritin (Fs), hemoglobin, hematocrit, soluble transferrin receptors and PH. The prevalence of anemia and of subclinical iron deficiency in the whole group (infected + non-infected) reached 10 and 60% respectively with no differences between groups. However, in the group of non-infected children, serum PH correlated (r=0.730/ p<0.001) with Fs levels whereas in the infected children, PH did not correlate with Fs but it correlated with the severity of the infection (r = 0.52/p<0.001). The tendency of PH to increase with the severity of infection could explain the higher prevalence of iron deficiency seen in Hp infection.

O eixo hepcidina-ferroportina é determinante na homeostase do ferro. Níveis elevados de hepcidina reduzem a capacidade de absorção intestinal do ferro, bem como sua mobilização entre tecidos. Uma condição que produz valores séricos elevados de hepcidina é a infecção. Como a infecção pelo Helicobacter pylori (Hp) predispõe a uma deficiência de ferro, neste estudo foram avaliados os níveis séricos de Pro-hepcidina (PH), um precursor da hepcidina em um grupo de estudantes assintomáticos infectados com Hp (80 crianças) e foram comparados com um grupo similar de crianças saudáveis (59 crianças). Os resultados mostraram que as crianças infectadas em que se detectou a presença de Hp (método de ar exalado) tinham valores de proteína C-reativa (PCR) significativamente mais elevada do que as crianças saudáveis. Ambos os grupos tiveram valores semelhantes de adequação da ingestão de ferro, ferritina sérica (Fs), hemoglobina, hematócrito, receptores solúveis de transferrina. A prevalência de anemia e deficiência subclínica de ferro no grupo total (infectados + não infectados) foi de 10 e 60%, respectivamente, sem diferenças entre os grupos. No entanto, no grupo de crianças saudáveis a PH sérica correlacionou significativamente (r=0,730/p<0,001) com os níveis de Fs, ao passo que em crianças infectadas, os níveis de PH não correlacionaram com a Fs, mas correlacionaram com a gravidade da infecção (r=0,52/p<0,001). Esta tendência da PH a aumentar com a gravidade da infecção poderia explicar a elevada prevalência de deficiência de ferro em pacientes infectados com Hp.

Impurity determination for hepcidin by liquid chromatography-high resolution and ion mobility mass spectrometry for the value assignment of candidate primary calibrators.

In metrology institutes, the state-of-the-art for purity analysis of peptides/proteins mainly addresses short and unfolded peptides. Important developments are anticipated for the characterization of nonlinear peptides or proteins. Hepcidin 1-25 is an interesting model system because this small protein contains four disulfide bridges with a particular connectivity that is difficult to reproduce and could induce a bias in quantification. Hepcidin 1-25 is involved in iron-related disorders and anemia, in an inflammatory context, and its clinical relevance in neurodegenerative disorders is under investigation. It is also an emerging biomarker. Recent inter-laboratory studies showed a need for standardization of hepcidin assay and the need to produce certified reference materials. This paper discusses two hepcidin standards from different synthesis pathways that have been characterized by high-resolution mass spectrometry and ion mobility mass spectrometry.

Added value of hepcidin quantification for the diagnosis and follow-up of anemia-related diseases.

Iron homeostasis is based on a strict control of both intestinal iron absorption and iron recycling through reticulo-endothelial system. Hepcidin controls the iron fluxes in order to maintain sufficient iron levels for erythropoietic activities, hemoproteins synthesis or enzymes function, but also to limit its toxic accumulation throughout the body. Hepcidin expression is regulated by various stimuli: inflammation and iron stimulate the production of the peptide, while anemia, erythropoiesis and hypoxia repress its production. Regulation of hepcidin expression is not so simple in complex pathological situations such as hemolytic anemia, cancer or chronic inflammation. Serum hepcidin quantification in association with the diagnostic tests currently available is quite promising for the diagnosis or the follow-up of anemia in those conditions. This study is part of the working group « Clinical interests of hepcidin quantification ¼ of the Société française de biologie clinique.