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Wacka E, Nicikowski J, Jarmuzek P, Zembron-Lacny A. Anemia and Its Connections to Inflammation in Older Adults: A Review. J Clin Med 2024; 13:2049. [PMID: 38610814 PMCID: PMC11012269 DOI: 10.3390/jcm13072049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 03/29/2024] [Accepted: 03/31/2024] [Indexed: 04/14/2024] Open
Abstract
Anemia is a common hematological disorder that affects 12% of the community-dwelling population, 40% of hospitalized patients, and 47% of nursing home residents. Our understanding of the impact of inflammation on iron metabolism and erythropoiesis is still lacking. In older adults, anemia can be divided into nutritional deficiency anemia, bleeding anemia, and unexplained anemia. The last type of anemia might be caused by reduced erythropoietin (EPO) activity, progressive EPO resistance of bone marrow erythroid progenitors, and the chronic subclinical pro-inflammatory state. Overall, one-third of older patients with anemia demonstrate a nutritional deficiency, one-third have a chronic subclinical pro-inflammatory state and chronic kidney disease, and one-third suffer from anemia of unknown etiology. Understanding anemia's pathophysiology in people aged 65 and over is crucial because it contributes to frailty, falls, cognitive decline, decreased functional ability, and higher mortality risk. Inflammation produces adverse effects on the cells of the hematological system. These effects include iron deficiency (hypoferremia), reduced EPO production, and the elevated phagocytosis of erythrocytes by hepatic and splenic macrophages. Additionally, inflammation causes enhanced eryptosis due to oxidative stress in the circulation. Identifying mechanisms behind age-related inflammation is essential for a better understanding and preventing anemia in older adults.
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Affiliation(s)
- Eryk Wacka
- Department of Applied and Clinical Physiology, Collegium Medicum University of Zielona Gora, 65-417 Zielona Gora, Poland; (J.N.); (A.Z.-L.)
| | - Jan Nicikowski
- Department of Applied and Clinical Physiology, Collegium Medicum University of Zielona Gora, 65-417 Zielona Gora, Poland; (J.N.); (A.Z.-L.)
| | - Pawel Jarmuzek
- Department of Neurosurgery and Neurology, Collegium Medicum University of Zielona Gora, 65-417 Zielona Gora, Poland;
| | - Agnieszka Zembron-Lacny
- Department of Applied and Clinical Physiology, Collegium Medicum University of Zielona Gora, 65-417 Zielona Gora, Poland; (J.N.); (A.Z.-L.)
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Oppen K, Brede C, Skadberg Ø, Steinsvik T, Holter JC, Michelsen AE, Heggelund L. Hepcidin analysis in pneumonia: Comparison of immunoassay and LC-MS/MS. Ann Clin Biochem 2023; 60:298-305. [PMID: 36759502 PMCID: PMC10552342 DOI: 10.1177/00045632231159529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2023] [Indexed: 02/11/2023]
Abstract
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.
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Affiliation(s)
- Kjersti Oppen
- Department of Laboratory Medicine, Drammen Hospital, Vestre Viken Hospital Trust, Norway
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway
- Institute of Clinical Medicine, University of Oslo, Norway
| | - Cato Brede
- Department of Medical Biochemistry, Stavanger University Hospital, Norway
- Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, Norway
| | - Øyvind Skadberg
- Department of Medical Biochemistry, Stavanger University Hospital, Norway
| | - Trude Steinsvik
- Department of Laboratory Medicine, Drammen Hospital, Vestre Viken Hospital Trust, Norway
| | - Jan Cato Holter
- Institute of Clinical Medicine, University of Oslo, Norway
- Department of Microbiology, Oslo University Hospital, Norway
| | - Annika E Michelsen
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Norway
- Institute of Clinical Medicine, University of Oslo, Norway
| | - Lars Heggelund
- Department of Internal Medicine, Drammen Hospital, Vestre Viken Hospital Trust, Norway
- Department of Clinical Science, Bergen Integrated Diagnostic Stewardship Cluster, Faculty of Medicine, University of Bergen, Norway
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Punt AM, Wieman JC, van der Elst KC, Huitema AD, Lentjes EG. An easy, fast, and efficient assay for the quantification of peptide Hepcidin-25 in serum and plasma with LC-MS/MS. Ann Clin Biochem 2022; 59:330-337. [PMID: 35392660 DOI: 10.1177/00045632221095490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The peptide hormone hepcidin-25 plays an important role in iron metabolism. Low or high levels of hepcidin-25 are associated with various iron disorders; therefore, hepcidin-25 is an important biomarker. This study describes an easy and fast analytical assay for the quantification of hepcidin-25 with liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS Sample preparation was performed by protein precipitation with trichloroacetic acid, and injection onto a LC-MS/MS was directly conducted from a LoBind 96-well plate. RESULTS The concentration range covered by the quality control samples, ranged from 0.25 nmol/L (12.3% CV) to 11.9 nmol/L (CV < 9%). Matrix effect was limited (mean recovery of 99.9% with a CV of 6.4%). The assay was validated for serum, EDTA and heparin plasma. An international secondary reference material was used for calibration. The reference interval (90% CL) was estimated for hepcidin-25 by analysing serum and plasma samples from 156 healthy subjects with a lower limit: 0.12 (0.07-0.19) and upper limit: 11.2 nmol/L (9.5-13.0). CONCLUSIONS We present a fast and easy assay for the quantification of hepcidin-25 in serum and plasma samples. The assay was successfully used for the detection of various forms of hereditary haemolytic anaemias, to characterize the interplay between erythropoiesis and iron levels.
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Affiliation(s)
- Arjen M Punt
- Department of Clinical Pharmacy, Division of Laboratory Medicine and Pharmacy, 8124University Medical Center Utrecht, Utrecht, The Netherlands.,Central Diagnostic Laboratory, 8124University Medical Center Utrecht, Utrecht, The Netherlands
| | - Joëlle C Wieman
- Central Diagnostic Laboratory, 8124University Medical Center Utrecht, Utrecht, The Netherlands
| | - Kim Cm van der Elst
- Department of Clinical Pharmacy, Division of Laboratory Medicine and Pharmacy, 8124University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alwin Dr Huitema
- Department of Clinical Pharmacy, University Medical Center Utrecht, Utrecht.,Department of Pharmacology, 541199Princess Máxima Center for Pediatric Oncology.,Department of Pharmacy & Pharmacology, 541199Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Eef Gwm Lentjes
- Central Diagnostic Laboratory, 8124University Medical Center Utrecht, Utrecht, The Netherlands
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Piesanen J, Valjakka J, Niemelä S, Borgenström M, Nikkari S, Hytönen V, Määttä J, Kunnas T. Hepcidin is potential regulator for renin activity. PLoS One 2022; 17:e0267343. [PMID: 35442992 PMCID: PMC9020709 DOI: 10.1371/journal.pone.0267343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/06/2022] [Indexed: 11/19/2022] Open
Abstract
An association between genetic variants in the genes HFE, HJV, BMP4 and arterial hypertension has been shown earlier. Proteins encoded by these genes participate in the signalling routes leading eventually to the production of the peptide hormone hepcidin. Mutations in these genes have been associated with the abnormal production of hepcidin in the body. This finding led to studies exploring the possible role of hepcidin in regulating the activity of blood pressure related renin-angiotensin system enzymes. We used molecular modelling to find out if it is possible for hepcidin to bind to the active site of the renin-angiotensin system enzymes, especially renin. Fluorometric assays were used to evaluate the inhibitory effect of hepcidin on renin as well as angiotensin converting enzymes 1 and 2. Finally, bio-layer interferometry technique was used to study hepcidin binding to renin. The molecular modelling showed that hepcidin seems to have similar binding properties to the renin active site as angiotensinogen does. Based on fluorometric enzyme activity assay, hepcidin has an inhibitory effect on renin in vitro, too. However, angiotensin converting enzymes 1 and 2 were not inhibited remarkably by hepcidin-25. In bio-layer interferometry analysis hepcidin-renin binding was concentration dependent. Our results suggest that hepcidin could act as an inhibitor to the renin. Nowadays, there is no known biological inhibitor for renin in vivo and our finding may thus have important clinical implications.
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Affiliation(s)
- Jaakko Piesanen
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Jarkko Valjakka
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Sanna Niemelä
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | | | - Seppo Nikkari
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Vesa Hytönen
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Juha Määttä
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Tarja Kunnas
- Facult of Medicine and Health Technology, Tampere University, Tampere, Finland
- * E-mail:
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Clinical interpretation of serum hepcidin-25 in inflammation and renal dysfunction. J Mass Spectrom Adv Clin Lab 2022; 24:43-49. [PMID: 35403094 PMCID: PMC8983384 DOI: 10.1016/j.jmsacl.2022.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/16/2022] [Accepted: 03/27/2022] [Indexed: 11/22/2022] Open
Abstract
log[hepcidin]:log[ferritin] ratio may serve as a biomarker for iron deficiency in complex cases. Hepcidin testing is not warranted in patients with CRP > 10 mg/l and/or eGFR < 30 ml/min/1.73 m2. Inflammation is not a determinant of serum hepcidin-25 in the setting of renal dysfunction. eGFR is not a major determinant of serum hepcidin-25 concentration in patient with eGFR ≥ 30 ml/min/1.73 m2.
Introduction Hepcidin is a hormone that regulates systemic iron homeostasis. Serum hepcidin levels are under the influence of various stimuli, particularly inflammation and renal dysfunction. The measurement of hepcidin in circulation is a potentially useful clinical tool in the diagnosis, monitoring and treatment of iron metabolism disorder, although clinical interpretation of hepcidin level remains difficult. We evaluated he diagnostic potential and limitations of hepcidin-25 by investigating its relationship with iron and hematological indices, inflammation, and renal dysfunction. Methods This retrospective study included 220 adult patients not requiring dialysis. Variations of biologically active hepcidin-25 were examined using a mass spectrometry-based assay in various inflammatory and renal states. The log[hepcidin]:log[ferritin] ratio was calculated as an hepcidin index. Results In 220 adult patients not requiring dialysis, variation in hepcidin-25 level was significantly larger once CRP exceeded 10 mg/l (p < 0.001). Inflammation was not a determinant of hepcidin-25 in the setting of renal dysfunction. Hepcidin-25 median (7.37 nM) and variance were significantly higher (p < 0.001), once estimated glomerular filtration rate (eGFR) dropped below 30 ml/min/1.73 m2. The log[hepcidin]:log[ferritin] index normalized hepcidin levels. Patients with iron deficiency have a notably lower index when compared to controls (-0.66 vs 0.3). Conclusion Severe renal dysfunction (eGFR < 30) affected hepcidin-25 expression and clearance to variable degree between individuals. Although, hepcidin-25 testing is not warranted in patients with infection, inflammatory autoimmune conditions (CRP > 10 mg/l) and/or severe renal dysfunction (eGFR < 30), the hepcidin index may serve as a potential biomarker for iron deficiency in complex cases.
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Jayakumar D, S Narasimhan KK, Periandavan K. Triad role of hepcidin, ferroportin, and Nrf2 in cardiac iron metabolism: From health to disease. J Trace Elem Med Biol 2022; 69:126882. [PMID: 34710708 DOI: 10.1016/j.jtemb.2021.126882] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 09/29/2021] [Accepted: 10/19/2021] [Indexed: 11/28/2022]
Abstract
Iron is an essential trace element required for several vital physiological and developmental processes, including erythropoiesis, bone, and neuronal development. Iron metabolism and oxygen homeostasis are interlinked to perform a vital role in the functionality of the heart. The metabolic machinery of the heart utilizes almost 90 % of oxygen through the electron transport chain. To handle this tremendous level of oxygen, the iron metabolism in the heart is utmost crucial. Iron availability to the heart is therefore tightly regulated by (i) the hepcidin/ferroportin axis, which controls dietary iron absorption, storage, and recycling, and (ii) iron regulatory proteins 1 and 2 (IRP1/2) via hypoxia inducible factor 1 (HIF1) pathway. Despite iron being vital to the heart, recent investigations have demonstrated that iron imbalance is a common manifestation in conditions of heart failure (HF), since free iron readily transforms between Fe2+ and Fe3+via the Fenton reaction, leading to reactive oxygen species (ROS) production and oxidative damage. Therefore, to combat iron-mediated oxidative stress, targeting Nrf2/ARE antioxidant signaling is rational. The involvement of Nrf2 in regulating several genes engaged in heme synthesis, iron storage, and iron export is beginning to be uncovered. Consequently, it is possible that Nrf2/hepcidin/ferroportin might act as an epicenter connecting iron metabolism to redox alterations. However, the mechanism bridging the two remains obscure. In this review, we tried to summarize the contemporary insight of how cardiomyocytes regulate intracellular iron levels and discussed the mechanisms linking cardiac dysfunction with iron imbalance. Further, we emphasized the impact of Nrf2 on the interplay between systemic/cardiac iron control in the context of heart disease, particularly in myocardial ischemia and HF.
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Affiliation(s)
- Deepthy Jayakumar
- Department of Medical Biochemistry, Dr. ALM Post Graduate Institute for Basic Medical Sciences, University of Madras, Chennai, 600113, Tamil Nadu, India
| | - Kishore Kumar S Narasimhan
- Department of Pharmacology and Neurosciences, Creighton University, 2500 California Plaza, Omaha, NE, USA
| | - Kalaiselvi Periandavan
- Department of Medical Biochemistry, Dr. ALM Post Graduate Institute for Basic Medical Sciences, University of Madras, Chennai, 600113, Tamil Nadu, India.
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Wakakuri H, Hyodo H, Ohara T, Yasutake M. Serum Hepcidin-25 Levels Reflect the Presence of Bacteremia in Patients with Systemic Inflammatory Response Syndrome. J NIPPON MED SCH 2019; 86:91-97. [PMID: 31130570 DOI: 10.1272/jnms.jnms.2019_86-204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Hepcidin-25 is a key regulatory hormone of iron homeostasis in humans, and its production is greatly upregulated by inflammation as well as iron overload. The aim of this study was to investigate the pathophysiological role of hepcidin-25 in patients with systemic inflammatory response syndrome (SIRS). METHODS We enrolled 113 consecutive patients (aged 63.4±21, 50 men, 63 women), with 2 or more SIRS criteria, who were admitted to our department of general medicine between August 1, 2015 and August 31, 2017. We measured complete blood cell count and serum levels of hepcidin-25, iron, iron-binding capacity, ferritin, blood urea nitrogen, creatinine, albumin, and C-reactive protein (CRP) on admission. The patients were divided into 3 group: a bacteremia group (27 patients), a culture-negative bacterial infection group (60 patients), and a non-bacterial infection group (26 patients). RESULTS Hepcidin-25 levels were found to be comparable in terms of SIRS criteria: 162 [2.8-579], 193 [2.24-409], and 180 [89.2-421] ng/mL in patients with 2, 3, and 4 criteria, respectively (P=0.533). However, hepcidin-25 levels were significantly higher in the bacteremia group (209 [56.7-579] ng/mL) than in either the culture-negative bacterial infection group (168 [2.24-418] ng/mL) or the non-bacterial infection group (142 [2.8-409] ng/mL). A significant positive correlation between hepcidin-25 and CRP levels was noted in the bacteremia group (r=0.528, P=0.005) and non-bacterial infection group (r=0.648, P<0.001). Moreover, iron and ferritin levels were significantly lower in the bacteremia group than in the non-bacterial infection group. CONCLUSIONS Our findings suggest that hepcidin-25 level may reflect the presence of bacteremia as well as the severity of inflammation in patients with SIRS.
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Affiliation(s)
- Hiroaki Wakakuri
- Department of General Medicine and Health Science, Nippon Medical School
| | - Hideya Hyodo
- Department of General Medicine and Health Science, Nippon Medical School
| | - Toshihiko Ohara
- Department of General Medicine and Health Science, Nippon Medical School
| | - Masahiro Yasutake
- Department of General Medicine and Health Science, Nippon Medical School
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Moghieb A, Tesfay L, Nie S, Gritsenko M, Fillmore TL, Jacobs JM, Smith RD, Torti FM, Torti SV, Shi T, Ansong C. A Targeted Mass Spectrometric Assay for Reliable Sensitive Hepcidin Quantification. Sci Rep 2019; 9:7264. [PMID: 31086210 PMCID: PMC6513854 DOI: 10.1038/s41598-019-43756-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 03/28/2019] [Indexed: 12/31/2022] Open
Abstract
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.
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Affiliation(s)
- Ahmed Moghieb
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Lia Tesfay
- Departments of Molecular Biology and Biophysics, University of Connecticut, Farmington, CT, USA
| | - Song Nie
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Marina Gritsenko
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Thomas L Fillmore
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Jon M Jacobs
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Richard D Smith
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Frank M Torti
- Department of Medicine, UConn Health Center, Farmington, CT, USA
| | - Suzy V Torti
- Departments of Molecular Biology and Biophysics, University of Connecticut, Farmington, CT, USA
| | - Tujin Shi
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA.
| | - Charles Ansong
- Biological Science Division, Pacific Northwest National Laboratory, Richland, WA, USA.
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Stevenson MJ, Uyeda KS, Harder NHO, Heffern MC. Metal-dependent hormone function: the emerging interdisciplinary field of metalloendocrinology. Metallomics 2019; 11:85-110. [PMID: 30270362 PMCID: PMC10249669 DOI: 10.1039/c8mt00221e] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
For over 100 years, there has been an incredible amount of knowledge amassed concerning hormones in the endocrine system and their central role in human health. Hormones represent a diverse group of biomolecules that are released by glands, communicate signals to their target tissue, and are regulated by feedback loops to maintain organism health. Many disease states, such as diabetes and reproductive disorders, stem from misregulation or dysfunction of hormones. Increasing research is illuminating the intricate roles of metal ions in the endocrine system where they may act advantageously in concert with hormones or deleteriously catalyze hormone-associated disease states. As the critical role of metal ions in the endocrine system becomes more apparent, it is increasingly important to untangle the complex mechanisms underlying the connections between inorganic biochemistry and hormone function to understand and control endocrinological phenomena. This tutorial review harmonizes the interdisciplinary fields of endocrinology and inorganic chemistry in the newly-termed field of "metalloendocrinology". We describe examples linking metals to both normal and aberrant hormone function with a focus on highlighting insight to molecular mechanisms. Hormone activities related to both essential metal micronutrients, such as copper, iron, zinc, and calcium, and disruptive nonessential metals, such as lead and cadmium are discussed.
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Affiliation(s)
- Michael J Stevenson
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
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Serum Concentration of Hepcidin as an Indicator of Iron Reserves in Children. J Med Biochem 2018; 37:456-464. [PMID: 30584405 PMCID: PMC6298481 DOI: 10.2478/jomb-2018-0003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 02/06/2018] [Indexed: 12/27/2022] Open
Abstract
Background Anemia represents a significant cause of maternal and perinatal mortality, as well as child mortality. The aim of the research was to determine the serum concentration of hepcidin in children aged 6 months to 2 years and adolescents aged 11 to 19 years which suffer from iron deficiency anemia and compare it with the serum concentration of hepcidin in the control groups, as well as to determine its connection with the parameters of the iron metabolism. Methods The research included 173 examinees, 89 of them suffered from iron deficiency anemia and 84 did not suffer from iron deficiency anemia (the latter represented the control group). Blood samples were collected from all study participants. The samples were analyzed for complete blood count and parameters of iron metabolism. ELISA method was used for establishing serum hepcidin levels. Results The research showed that the concentration of hepcidin is statistically lower in children (4.4 ng/mL) and adolescents (4.1 ng/mL) who suffer from iron deficiency anemia in comparison with the control group (14 ng/mL, 10 ng/mL, respectively). The positive correlation between serum hepcidin level and iron in the serum, ferritin, the mean corpuscular volume and transferrin saturation was confirmed, but the negative one occurred in serum hepcidin level, transferrin and reticulocytes. Conclusions The age of the examinees does not influence the level of serum hepcidin which makes it a more sensitive indicator of the level of iron in the body. Besides this, serum hepcidin is a reliable biological marker for the assessment of iron deficiency anemia.
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Serum hepcidin may be a novel uremic toxin, which might be related to erythropoietin resistance. Sci Rep 2017; 7:4260. [PMID: 28652624 PMCID: PMC5484693 DOI: 10.1038/s41598-017-04664-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/18/2017] [Indexed: 12/11/2022] Open
Abstract
The clinical importance of serum hepcidin in non-dialysis chronic kidney disease (CKD) patients is unclear. The database of a large-scale multicentre prospective study in Korea of 2238 patients enrolled from 2011–2016 was analysed. After excluding patients with missing serum hepcidin (n = 125) and haemoglobin (n = 23) levels, the study included 2090 non-dialysis CKD patients. Markers of inflammation and iron status were positively associated with serum hepcidin level, regardless of CKD stage. However, estimated glomerular filtration rate was inversely associated with serum hepcidin level, particularly in patients with CKD stages 3b–5 but not in those with CKD stages 1–3a. Use of erythropoiesis-stimulating agents was associated with increased serum hepcidin levels, particularly in patients with CKD stages 3b–5 but not in those with CKD stages 1–3a, and serum hepcidin levels positively correlated with the dose of erythropoiesis-stimulating agent. These findings suggest that serum hepcidin may be a uremic toxin and play an important role in erythropoietin resistance. However, future prospective studies are needed to confirm our results.
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12
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Measurement of hepcidin isoforms in human serum by liquid chromatography with high resolution mass spectrometry. Bioanalysis 2017; 9:541-553. [DOI: 10.4155/bio-2016-0286] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Aim: Hepcidin-25 is the master regulator of iron homeostasis. N-truncated isoforms of hepcidin-25 have been identified (hepcidin-20, -22, -24), although data on the concentrations of these isoforms are sparse. Materials & methods: Serum was mixed with aqueous formic acid, and the supernatant loaded onto a 96-well-SPE-plate. Eluted analytes were analyzed using LC–HR-MS. Forty-seven paired dipotassium-EDTA human plasma and serum samples were analyzed. Results: The LLOQ was 1 μg/l (all analytes). Accuracy and precision were acceptable. There was a good correlation (R2 >0.90, all analytes) between matrices. The median (range) serum hepcidin-20, -22, -24 and -25 concentrations measured were 4 (1–40), 8 (2–20), 8 (1–50) and 39 (1–334) μg/l, respectively. Conclusion: LC–HR-MS is widely applicable to the measurement of hepcidin-25, and truncated isoforms.
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The three isoforms of hepcidin in human serum and their processing determined by liquid chromatography-tandem mass spectrometry (LC-tandem MS). Int J Hematol 2016; 103:34-43. [PMID: 26462810 DOI: 10.1007/s12185-015-1885-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/01/2015] [Accepted: 10/01/2015] [Indexed: 10/23/2022]
Abstract
Hepcidin, the iron regulatory hormone, has three isoforms; -20, -22 and -25. While hepcidin-25 has been studied extensively, the physiological significance of other isoforms remains poorly understood. Using a quantitative method based on liquid chromatography-tandem mass spectrometry (LC-tandem MS) developed by our group, we quantified hepcidin isoforms in human serum to elucidate their characteristics, and investigated the role of hepatocytes in isoform processing. Hepcidin isoforms in serum obtained from 40 healthy volunteers were quantified. Synthetic hepcidin peptides were added to healthy serum, and to HepG2 culture media, and hepcidin isoform concentrations determined. All three hepcidin isoforms were detected in human serum; however, hepcidin-25 concentrations were highest. The three hepcidin isoforms showed a strong positive correlation with each other and with serum ferritin. Additionally, while hepcidin-20 was strongly correlated with serum creatinine, the other isoforms were not. Hepcidin-20 and -25 levels were also increased in chronic kidney disease (CKD) serum. Hepcidin-22 rapidly degraded into hepcidin-20, whereas hepcidin-25 remained relatively stable. Finally, hepcidin-22 degradation into hepcidin-20 was accelerated in the presence of HepG2. This method has enabled us to reveal fundamental characteristics of the three hepcidin isoforms in serum and may be a powerful tool for quantifying hepcidin isoform expression and processing.
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Abstract
The discovery of the iron-regulatory hormone hepcidin in 2001 has revolutionized our understanding of iron disorders, and its measurement should advance diagnosis/treatment of these conditions. Although several assays have been developed, a gold standard is still lacking, and efforts toward harmonization are ongoing. Nevertheless, promising applications can already be glimpsed, ranging from the use of hepcidin levels for diagnosing iron-refractory iron deficiency anemia to global health applications such as guiding safe iron supplementation in developing countries with high infection burden.
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van Swelm RPL, Wetzels JFM, Verweij VGM, Laarakkers CMM, Pertijs JCLM, van der Wijst J, Thévenod F, Masereeuw R, Swinkels DW. Renal Handling of Circulating and Renal-Synthesized Hepcidin and Its Protective Effects against Hemoglobin-Mediated Kidney Injury. J Am Soc Nephrol 2016; 27:2720-32. [PMID: 26825531 DOI: 10.1681/asn.2015040461] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 12/12/2015] [Indexed: 11/03/2022] Open
Abstract
Urinary hepcidin may have protective effects against AKI. However, renal handling and the potential protective mechanisms of hepcidin are not fully understood. By measuring hepcidin levels in plasma and urine using mass spectrometry and the kidney using immunohistochemistry after intraperitoneal administration of human hepcidin-25 (hhep25) in C57Bl/6N mice, we showed that circulating hepcidin is filtered by the glomerulus and degraded to smaller isoforms detected in urine but not plasma. Moreover, hepcidin colocalized with the endocytic receptor megalin in proximal tubules, and compared with wild-type mice, megalin-deficient mice showed higher urinary excretion of injected hhep25 and no hepcidin staining in proximal tubules that lack megalin. This indicates that hepcidin is reaborbed in the proximal tubules by megalin dependent endocytosis. Administration of hhep25 concomitant with or 4 hours after a single intravenous dose of hemoglobin abolished hemoglobin-induced upregulation of urinary kidney injury markers (NGAL and KIM-1) and renal Interleukin-6 and Ngal mRNA observed 24 hours after administration but did not affect renal ferroportin expression at this point. Notably, coadministration of hhep25 and hemoglobin but not administration of either alone greatly increased renal mRNA expression of hepcidin-encoding Hamp1 and hepcidin staining in distal tubules. These findings suggest a role for locally synthesized hepcidin in renal protection. Our observations did not support a role for ferroportin in hhep25-mediated protection against hemoglobin-induced early injury, but other mechanisms of cellular iron handling may be involved. In conclusion, our data suggest that both systemically delivered and locally produced hepcidin protect against hemoglobin-induced AKI.
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Affiliation(s)
| | | | | | | | | | | | - Frank Thévenod
- Institute of Physiology, Pathophysiology and Toxicology, Center for Biomedical Training and Research, University of Witten/Herdecke, Witten, Germany; and
| | - Rosalinde Masereeuw
- Pharmacology and Toxicology, Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht, The Netherlands
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16
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Suárez-Ortegón MF, Moreno M, Arbeláez A, Xifra G, Mosquera M, Moreno-Navarrete JM, Aguilar-de Plata C, Esteve E, Ricart W, Fernández-Real JM. Circulating hepcidin in type 2 diabetes: A multivariate analysis and double blind evaluation of metformin effects. Mol Nutr Food Res 2015; 59:2460-70. [PMID: 26394887 DOI: 10.1002/mnfr.201500310] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 09/02/2015] [Accepted: 09/04/2015] [Indexed: 12/13/2022]
Abstract
SCOPE Very few studies have evaluated serum hepcidin in patients with type 2 diabetes and they have reported conflicting results. In addition, the effect of antidiabetic drugs on circulating hepcidin has not been explored so far. The aims of the study were to evaluate hepcidin concentrations and hepcidin/ferritin ratio in type 2 diabetes subjects and healthy non-diabetic controls and to evaluate the effect of metformin on hepcidin concentrations. METHODS AND RESULTS Study 1: Cross-sectional multivariate study of 239 non-diabetic individuals and 65 people with type 2 diabetes. The multivariate analysis included covariates of chronic inflammation, BMI, pharmacological treatment, menopausal status and insulin resistance. Study 2: Randomized, double-blinded, placebo-controlled 4-month trial metformin compared to placebo among 36 type 2 diabetic patients. In both groups diet was controlled by maintaining a hypocaloric intake across the trial. Hepcidin levels were significantly lower in patients with type 2 diabetes than in non-diabetic individuals either in crude or adjusted regression models (P<0.05). Hepcidin decreased in both arms of the trial (Placebo, p = 0.004; metformin, p = 0.022). CONCLUSION Circulating hepcidin was significantly and independently lower in type 2 diabetes. Metformin treatment is not associated with reductions in hepcidin but hypocaloric diet could be involved.
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Affiliation(s)
- Milton Fabián Suárez-Ortegón
- Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK.,Nutrition Group, Universidad del Valle, Cali, Colombia
| | - María Moreno
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
| | - Alejandra Arbeláez
- Nutrition Group, Universidad del Valle, Cali, Colombia.,Physiological Sciences Department, Universidad del Valle, Cali, Colombia
| | - Gemma Xifra
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
| | - Mildrey Mosquera
- Nutrition Group, Universidad del Valle, Cali, Colombia.,Physiological Sciences Department, Universidad del Valle, Cali, Colombia
| | - José María Moreno-Navarrete
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
| | - Cecilia Aguilar-de Plata
- Nutrition Group, Universidad del Valle, Cali, Colombia.,Physiological Sciences Department, Universidad del Valle, Cali, Colombia
| | - Eduardo Esteve
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
| | - Wifredo Ricart
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
| | - José Manuel Fernández-Real
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), CIBEROBN (CB06/03/010) and Instituto de Salud Carlos III (ISCIII), Girona, Spain
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17
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Valenti L, Messa P, Pelusi S, Campostrini N, Girelli D. Hepcidin levels in chronic hemodialysis patients: a critical evaluation. Clin Chem Lab Med 2014; 52:613-9. [PMID: 24231125 DOI: 10.1515/cclm-2013-0769] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/17/2013] [Indexed: 11/15/2022]
Abstract
Altered systemic iron metabolism is a key element of uremia, and functional iron deficiency mainly related to subclinical inflammation makes it difficult to maintain proper control of anemia in chronic hemodialysis patients (CHD). In the last decade, the hepatic hormone hepcidin has been progressively recognized as the master regulator of circulating iron levels through the modulation of cellular iron fluxes in response to iron stores, as well as to erythroid and inflammatory stimuli. Hepcidin is cleared by the kidney and progression of renal disease has been associated to increased serum hepcidin levels. This, in turn, reduces iron availability for erythropoiesis, suggesting anti-hepcidin strategies for improving anemia control. Moreover, hepcidin has been recently implicated in the pathogenesis of long-term complications of dialysis, like accelerated atherosclerosis. Initial studies almost invariably reported a sustained increase of serum hepcidin in chronic hemodialysis patients. Noteworthy, such studies included relatively few patients and controls that were poorly matched for major determinants of serum hepcidin at population level, i.e., age and gender. More recent data based on accurately matched larger series challenge the view that hepcidin is intrinsically increased in hemodialysis patients, showing a marked inter- and intra-individual variability of hormone levels. Here we take a critical look to the data published so far on hepcidin levels in CHD, analyze the reasons underlying the discrepancies in available studies and the hepcidin variability in CHD, and point out the need for further studies in large series of well-characterized CHD patients and controls.
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18
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Validation of hepcidin quantification in plasma using LC-HRMS and discovery of a new hepcidin isoform. Bioanalysis 2014; 5:2509-20. [PMID: 24138624 DOI: 10.4155/bio.13.225] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Hepcidin, a 25 amino acid peptide, plays an important role in iron homeostasis. Some hepcidin truncated peptides have antibiotic effects. RESULTS A new analytical method for hepcidin determination in human plasma using LC-HRMS operating in full-scan acquisition mode has been validated. The extraction consists of protein precipitation and a drying reconstitution step; a 2.1 x 50 mm (idxL) C18 analytical column was used. Detection specificity, stability, accuracy, precision and recoveries were determined. The LOQ/LOD were 0.25/0.1 nM, respectively. More than 600 injections of plasma extracts were performed, allowing evaluation of the assay robustness. Hepcidin-20, hepcidin-22 and a new isoform, hepcidin-24, were detected in patients. CONCLUSION The data underscore the usefulness of LC-HRMS for in-depth investigations related to hepcidin levels and pathways.
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Busti F, Campostrini N, Martinelli N, Girelli D. Iron deficiency in the elderly population, revisited in the hepcidin era. Front Pharmacol 2014; 5:83. [PMID: 24795637 PMCID: PMC4006029 DOI: 10.3389/fphar.2014.00083] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 04/04/2014] [Indexed: 12/13/2022] Open
Abstract
Iron deficiency (ID) is relatively common among the elderly population, contributing substantially to the high prevalence of anemia observed in the last decades of life, which in turn has important implications both on quality of life and on survival. In elderly subjects, ID is often multifactorial, i.e., due to multiple concurring causes, including inadequate dietary intake or absorption, occult bleeding, medications. Moreover, because of the typical multimorbidity of aged people, other conditions leading to anemia frequently coexist and make diagnosis of ID particularly challenging. Treatment of ID is also problematic in elderly, since response to oral iron is often slow, with a substantial fraction of patients showing refractoriness and requiring cumbersome intravenous administration. In the last decade, the discovery of the iron regulatory hormone hepcidin has revolutionized our understanding of iron pathophysiology. In this review, we revisit ID among elderly people in the light of the impressive recent advances on knowledge of iron regulation, and discuss how hepcidin may help in diagnosis and treatment of this common clinical condition.
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20
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Latour C, Kautz L, Besson-Fournier C, Island ML, Canonne-Hergaux F, Loréal O, Ganz T, Coppin H, Roth MP. Testosterone perturbs systemic iron balance through activation of epidermal growth factor receptor signaling in the liver and repression of hepcidin. Hepatology 2014; 59:683-94. [PMID: 23907767 DOI: 10.1002/hep.26648] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 07/18/2013] [Indexed: 12/14/2022]
Abstract
UNLABELLED Gender-related disparities in the regulation of iron metabolism may contribute to the differences exhibited by men and women in the progression of chronic liver diseases associated with reduced hepcidin expression, e.g., chronic hepatitis C, alcoholic liver disease, or hereditary hemochromatosis. However, their mechanisms remain poorly understood. In this study we took advantage of the major differences in hepcidin expression and tissue iron loading observed between Bmp6-deficient male and female mice to investigate the mechanisms underlying this sexual dimorphism. We found that testosterone robustly represses hepcidin transcription by enhancing Egfr signaling in the liver and that selective epidermal growth factor receptor (Egfr) inhibition by gefitinib (Iressa) in males markedly increases hepcidin expression. In males, where the suppressive effects of testosterone and Bmp6-deficiency on hepcidin expression are combined, hepcidin is more strongly repressed than in females and iron accumulates massively not only in the liver but also in the pancreas, heart, and kidneys. CONCLUSION Testosterone-induced repression of hepcidin expression becomes functionally important during homeostatic stress from disorders that result in iron loading and/or reduced capacity for hepcidin synthesis. These findings suggest that novel therapeutic strategies targeting the testosterone/EGF/EGFR axis may be useful for inducing hepcidin expression in patients with iron overload and/or chronic liver diseases.
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Affiliation(s)
- Chloé Latour
- Inserm, U1043, Toulouse, France; CNRS, U5282, Toulouse, France; Université de Toulouse, UPS, Centre de Physiopathologie de Toulouse Purpan (CPTP), Toulouse, France
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21
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Abstract
The iron hormone hepcidin and its receptor and cellular iron exporter ferroportin control the major fluxes of iron into blood plasma: intestinal iron absorption, the delivery of recycled iron from macrophages, and the release of stored iron from hepatocytes. Because iron losses are comparatively very small, iron absorption and its regulation by hepcidin and ferroportin determine total body iron content. Hepcidin is in turn feedback-regulated by plasma iron concentration and iron stores, and negatively regulated by the activity of erythrocyte precursors, the dominant consumers of iron. Hepcidin and ferroportin also play a role in host defense and inflammation, and hepcidin synthesis is induced by inflammatory signals including interleukin-6 and activin B. This review summarizes and discusses recent progress in molecular characterization of systemic iron homeostasis and its disorders, and identifies areas for further investigation.
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Laarakkers CMM, Wiegerinck ET, Klaver S, Kolodziejczyk M, Gille H, Hohlbaum AM, Tjalsma H, Swinkels DW. Improved mass spectrometry assay for plasma hepcidin: detection and characterization of a novel hepcidin isoform. PLoS One 2013; 8:e75518. [PMID: 24124495 PMCID: PMC3790851 DOI: 10.1371/journal.pone.0075518] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 08/14/2013] [Indexed: 12/15/2022] Open
Abstract
Mass spectrometry (MS)-based assays for the quantification of the iron regulatory hormone hepcidin are pivotal to discriminate between the bioactive 25-amino acid form that can effectively block the sole iron transporter ferroportin and other naturally occurring smaller isoforms without a known role in iron metabolism. Here we describe the design, validation and use of a novel stable hepcidin-25+40 isotope as internal standard for quantification. Importantly, the relative large mass shift of 40 Da makes this isotope also suitable for easy-to-use medium resolution linear time-of-flight (TOF) platforms. As expected, implementation of hepcidin-25+40 as internal standard in our weak cation exchange (WCX) TOF MS method yielded very low inter/intra run coefficients of variation. Surprisingly, however, in samples from kidney disease patients, we detected a novel peak (m/z 2673.9) with low intensity that could be identified as hepcidin-24 and had previously remained unnoticed due to peak interference with the formerly used internal standard. Using a cell-based bioassay it was shown that synthetic hepcidin-24 was, like the -22 and -20 isoforms, a significantly less potent inducer of ferroportin degradation than hepcidin-25. During prolonged storage of plasma at room temperature, we observed that a decrease in plasma hepcidin-25 was paralleled by an increase in the levels of the hepcidin-24, -22 and -20 isoforms. This provides first evidence that all determinants for the conversion of hepcidin-25 to smaller inactive isoforms are present in the circulation, which may contribute to the functional suppression of hepcidin-25, that is significantly elevated in patients with renal impairment. The present update of our hepcidin TOF MS assay together with improved insights in the source and preparation of the internal standard, and sample stability will further improve our understanding of circulating hepcidin and pave the way towards further optimization and standardization of plasma hepcidin assays.
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Affiliation(s)
- Coby M. M. Laarakkers
- Laboratory of Genetic, Endocrine and Metabolic Diseases, Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands
- Hepcidinanalysis.com, Nijmegen, The Netherlands
| | - Erwin T. Wiegerinck
- Laboratory of Genetic, Endocrine and Metabolic Diseases, Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands
- Hepcidinanalysis.com, Nijmegen, The Netherlands
| | - Siem Klaver
- Laboratory of Genetic, Endocrine and Metabolic Diseases, Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands
- Hepcidinanalysis.com, Nijmegen, The Netherlands
| | | | | | | | - Harold Tjalsma
- Laboratory of Genetic, Endocrine and Metabolic Diseases, Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands
- Hepcidinanalysis.com, Nijmegen, The Netherlands
| | - Dorine W. Swinkels
- Laboratory of Genetic, Endocrine and Metabolic Diseases, Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands
- Hepcidinanalysis.com, Nijmegen, The Netherlands
- * E-mail:
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Abstract
BACKGROUND Hepcidin, a peptide produced by hepatocytes, regulates body iron homeostasis. Inflammation increases serum hepcidin, and its determination can be useful in the differential diagnosis of anemias during inflammatory diseases. METHODS We measured serum hepcidin-25 and hepcidin-20 isoforms in 54 patients with inflammatory bowel diseases (IBD) and 54 reference subjects (36 healthy controls and 18 anemic patients without inflammation or renal failure). Disease activity, blood counts, iron status, and erythropoiesis-related parameters were obtained for all study subjects. RESULTS In IBD hepcidin-25, the peptide bioactive isoform correlated positively with C-reactive protein and serum ferritin; an inverse correlation was observed with transferrin, the soluble transferrin receptor, and the soluble transferrin receptor to Log(ferritin) ratio. Similar correlations were found in reference subjects. Patients with anemia of inflammation had higher hepcidin-25 levels than those with iron deficiency anemia or a combination of iron deficiency anemia and inflammation (P = 0.0061). In patients with inflammation and serum ferritin concentration 100 to 200 ng/mL, hepcidin-25 was low, suggesting that these patients had iron deficiency. A serum hepcidin-25 concentration below 2.0 nM differentiated 85% of patients with iron deficiency anemia (with or without inflammation) from patients with anemia of inflammation. In IBD, hepcidin-20 correlated with both hepcidin-25 and C-reactive protein. CONCLUSIONS In IBD, iron stores, inflammation, and iron requirement for erythropoiesis influence serum hepcidin-25. Hepcidin-25 determination can be useful in the differential diagnosis of IBD-associated anemias. Serum hepcidin-20 is linked to hepcidin-25, but inflammation has an independent regulatory role on its concentration, indicating that hepcidin-20 may have a biological function.
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24
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25
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Pelusi S, Girelli D, Rametta R, Campostrini N, Alfieri C, Traglia M, Dongiovanni P, Como G, Toniolo D, Camaschella C, Messa P, Fargion S, Valenti L. The A736V TMPRSS6 polymorphism influences hepcidin and iron metabolism in chronic hemodialysis patients: TMPRSS6 and hepcidin in hemodialysis. BMC Nephrol 2013; 14:48. [PMID: 23433094 PMCID: PMC3585892 DOI: 10.1186/1471-2369-14-48] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 02/14/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aim of this study was to evaluate whether the A736V TMPRSS6 polymorphism, a major genetic determinant of iron metabolism in healthy subjects, influences serum levels of hepcidin, the hormone regulating iron metabolism, and erythropoiesis in chronic hemodialysis (CHD). METHODS To this end, we considered 199 CHD patients from Northern Italy (157 with hepcidin evaluation), and 188 healthy controls without iron deficiency, matched for age and gender. Genetic polymorphisms were evaluated by allele specific polymerase chain reaction assays, and hepcidin quantified by mass spectrometry. RESULTS Serum hepcidin levels were not different between the whole CHD population and controls (median 7.1, interquartile range (IQR) 0.55-17.1 vs. 7.4, 4.5-17.9 nM, respectively), but were higher in the CHD subgroup after exclusion of subjects with relative iron deficiency (p = 0.04). In CHD patients, the A736V TMPRSS6 polymorphism influenced serum hepcidin levels in individuals positive for mutations in the HFE gene of hereditary hemochromatosis (p < 0.0001). In particular, the TMPRSS6 736 V variant was associated with higher hepcidin levels (p = 0.017). At multivariate analysis, HFE and A736V TMPRSS6 genotypes predicted serum hepcidin independently of ferritin and C reactive protein (p = 0.048). In patients without acute inflammation and overt iron deficiency (C reactive protein <1 mg/dl and ferritin >30 ng/ml; n = 86), hepcidin was associated with lower mean corpuscular volume (p = 0.002), suggesting that it contributed to iron-restricted erythropoiesis. In line with previous results, in patients without acute inflammation and severe iron deficiency the "high hepcidin" 736 V TMPRSS6 variant was associated with higher erythropoietin maintenance dose (p = 0.016), independently of subclinical inflammation (p = 0.02). CONCLUSIONS The A736V TMPRSS6 genotype influences hepcidin levels, erythropoiesis, and anemia management in CHD patients. Evaluation of the effect of TMPRSS6 genotype on clinical outcomes in prospective studies in CHD may be useful to predict the outcomes of hepcidin manipulation, and to guide treatment personalization by optimizing anemia management.
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Affiliation(s)
- Serena Pelusi
- Department of Pathophysiology and Transplantation, Internal Medicine, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milano, Italy
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Zolla L, D'Alessandro A. Preface to the Special Issue: Integrated omics. J Proteomics 2012; 76 Spec No.:3-9. [PMID: 23079073 DOI: 10.1016/j.jprot.2012.10.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 10/08/2012] [Indexed: 11/30/2022]
Affiliation(s)
- Lello Zolla
- Tuscia University, Largo dell'Università, snc, 01100 Viterbo, Italy.
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