Academic literature on the topic 'Hepcidin, ERFE, sTfR, Iron metabolism'

Abstract Background The hemoglobin (Hb) response to the activin receptor type IIA ligand trap ACE-011 (Sotatercept) in non-transfusion-dependent thalassemia (NTDT), and the transfusion requirement response in TDT are described, but the mechanisms of action, clinical predictors and markers of response, are unclear. In principle, ACE-011 may act on early and/or late erythroblasts to decrease ineffective erythropoiesis (IE), both in healthy subjects and in thalassemia. As erythropoiesis intimately links to iron metabolism, changes in markers of iron metabolism relative to those of erythropoiesis may inform the mechanisms and developmental stage at which ACE-011 acts. Methods Markers of IE and iron metabolism in 46 thalassemia patients (30 NTDT, 16 TDT) were taken before and during a median follow up of 722.5 days, (IQR 830.5, range 152-1427) of escalating doses of ACE-011 (3-weekly 0.1 to 1.0 mg/kg s.c. injections), depending on the protocol, as part of the approved study (Cappellini, et al. 2018 under review). Markers of erythropoiesis included Hb, Reticulocytes (Ret), soluble transferrin receptor 1 (sTfR), growth differentiation factor 11 and 15 (GDF11, GDF15), erythroferrone (ERFE). Markers of iron metabolism included plasma hepcidin, serum ferritin (SF), transferrin saturation (TSAT), and non-transferrin-bound iron (NTBI). Data were analyzed using longitudinal multilevel model for change (LMMC) on STATA (Version 14) as generalized linear mixed model with random and fixed effects to account for repeated measures and highly complex temporal data structure. Final LMMCs were built to explain the change in Hb from baseline and the behavior of key biomarkers. Independent variables were entered into the models based on the study design (predictors from design) and theoretical background (predictors of interest and control variables). P value <0.05 was considered statistically significant. Results Predictors of response. In NTDT, Hb response associated positively with dose and duration of exposure (both at p<0.0001), and negatively with baseline EPO (p=0.002), GDF15 (p<0.0001) or TSAT. In TDT, accounting for transfusion effect, baseline GDF15 and EPO positively predicted Hb response while ERFE was a negative predictor (all at p<0.0001). Biomarker changes with time In NTDT, significant changes with time on study were increases in Hb, sTfR, ERFE and Ret and decreases in hepcidin, bilirubin, and NTBI. GDF15 showed no change. In TDT, GDF15, sTfR and ERFE increased, whereas hepcidin decreased. The Hb change was insignificant in TDT (as expected per protocol) and was dose-independent, however the mean 41% reduction in transfusion iron load rate (ILR) was dose dependent, implying an equivalent net production of Hb in TDT (Table 1). Other significant relationships Absolute hepcidin level in NTDT and TDT was negatively predicted by ERFE (p<0.0001): the first longitudinal demonstration of this association in thalassemia patients. GDF11, the target for ACE-011 that was shown previously to negatively regulate erythroid differentiation (Dussiot et al, Nat Med 2014), fell significantly on study (preliminary data). Significant reduction in indirect bilirubin in NTDT, implying reduced hemolysis, suggests improved quality of produced erythrocytes. Interpretation and conclusions NTDT patients allow a cleaner interpretation of biomarker changes as these are confounded in TDT by increased bone marrow stress from less transfusion. In NTDT, sTfR and ERFE (total erythropoiesis) increase on study while GDF15 (IE) and EPO do not. Thus Hb gain may result from increased effectiveness of late stage erythropoiesis (sTfR+ and ERFE+) possibly from decreased apoptosis and more rapid maturation (Carrancio et al, BJH 2014) in this compartment. We speculate that increased survival of those erythroid progenitor cells expressing TfR (and hence sTfR) and ERFE (hence increased ERFE) also explains the observed hepcidin reduction. Despite exposure to lower hepcidin, there is no iron loading: NTBI falls against stable SF in NTDT, consistent with shunting of iron into the sink of effective erythropoiesis. The reduction in GDF11 in vivo, not previously reported for ACE-011, is also consistent with increased apoptosis of the early progenitor pool and with improved erythroblast differentiation relative to proliferation as suggested in murine β-thalassemia treated with ACE-011 (Dussiot, et al. Nat Med 2014). Disclosures Garbowski: Vifor: Consultancy. Hermine:Erythec: Research Funding; AB Science: Consultancy, Equity Ownership, Honoraria, Research Funding; Celgene Corporation: Research Funding; Hybrigenics: Research Funding; Novartis: Research Funding. Cappellini:Sanofi/Genzyme: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Vifor: Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees. Origa:Bluebird Bio: Consultancy; Novartis: Honoraria; Cerus Corporation: Research Funding; Apopharma: Honoraria. Forni:Celgene: Research Funding; Novartis: Other: travel expenses, Research Funding; Shire: Research Funding; Roche: Consultancy; Apopharma: Other: DSM Board. Voskaridou:Acceleron: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene Corp: Membership on an entity's Board of Directors or advisory committees, Research Funding. Galactéros:Addmedica: Other: grant; Novartis: Other: grant. Taher:Novartis: Consultancy, Honoraria, Research Funding; La Jolla Pharmaceutical: Research Funding; Protagonist Therapeutics: Consultancy; Celgene Corp.: Research Funding; Ionis Pharmaceuticals: Consultancy. Ribeil:bluebird bio: Consultancy; Vitalaire: Other: grant; Addmedica: Other: grant; Cydan: Consultancy; Novartis: Consultancy. Laadem:Celgene: Employment, Equity Ownership. Miteva:Celgene Corporation: Employment, Other: grants. Zou:Celgene Corporation: Employment, Equity Ownership. Zinger:Celgene Corporation: Employment. Schwickart:Celgene Corporation: Employment, Equity Ownership. Sung:Celgene Corporation: Employment, Equity Ownership. Porter:Novartis: Consultancy; Cerus: Honoraria; Agios: Honoraria.

Objective: Iron overload (IO) is a common and life-threatening complication resulting from the therapy of AL and HCT patients. This study aimed to evaluate the prognostic value of 12 serum biomarkers of iron metabolism in pediatric patients treated for AL or undergoing HCT. Patients: Overall, 50 patients with AL after intensive treatment and 32 patients after HCT were prospectively included in the study. AL patients at diagnosis and healthy controls served as reference groups. Methods: The impact of the following 12 serum iron metabolism parameters on the outcome of AL/HCT patients was analyzed: iron, transferrin (Tf), total iron-binding capacity (TIBC), ferritin, ferritin heavy chains (FTH1), ferritin light chains (FTL), hepcidin, soluble hemojuvelin (sHJV), soluble ferroportin-1 (sFPN1), erythroferrone (ERFE), erythropoietin (EPO), and soluble transferrin receptor (sTfR). Results: With a median follow-up of 2.2 years, high levels of ferritin and low levels of sHJV had an adverse prognostic impact on OS and EFS in children after HCT. If these patients were combined with those with AL after intensive chemotherapy, the results were confirmed for OS and EFS both for ferritin and sHJV. Conclusions: Among the 12 analyzed serum parameters of iron metabolism, increased levels of ferritin and decreased levels of sHJV had an adverse prognostic impact on survival in children after HCT. More data are needed to clarify the relationship between ferritin, sHJV, and mortality of AL children after intensive chemotherapy, and more extensive prospective studies are required to prove sHJV predictivity.

Background. Extramedullary hematopoiesis (EMH) is common in non-transfusion-dependent thalassemia (NTDT) patients. Clinical presentations of EMH vary as MRI screening is not feasible. Hence, serum biomarkers are used to predict the risk of EMH. Materials and Methods. 52 NTDT patients, including 26 EMH (+) and 26 EMH (-), together with 26 healthy controls, were enrolled in this case-control study from 2013 to 2016. EMH was confirmed by computed tomography or MRI. Demographic, transfusion, genetic, laboratory, and liver iron concentration (LIC) data, as well as clinical complications, were analyzed. Results. EMH (+) patients had significantly higher serum ferritin (SF), growth differentiation factor 15 (GDF15), and erythropoietin (EPO) levels compared with EMH (-) patients and controls. The levels of erythroferrone (ERFE), hepcidin, and sTfR did not differ significantly between EMH (+) and EMH (-) patients (p>0.05). In NTDT patients, serum ERFE was not related to SF, LIC, hepcidin, sTfR, EPO, GDF15, and Hb levels. GDF15, EPO concentrations, and GDF15 to sTfR and GDF15 to EPO ratios are able to determine the presence of EMH with considerable sensitivity and specificity. Conclusions. GDF15, EPO, and GDF15 to EPO and GDF15 to sTfR ratios are potential biomarkers for the early prediction of NTDT in patients who are at risk for EMH.

Abstract Objectives Iron (Fe) homeostasis must be tightly regulated during pregnancy to meet both maternal and fetal Fe demands. Several hormones are known to impact Fe homeostasis including hepcidin, erythropoietin and erythroferrone (ERFE). Few data are available on determinants of ERFE in pregnant women or in their newborns at birth. The objective of this study was to characterize concentrations of ERFE across gestation and evaluate this hormone in relation to other Fe status biomarkers and regulatory hormones in mothers across pregnancy. Methods ERFE was measured in serum from pregnant adolescents (n = 166, age 14–19) or women carrying multiple fetuses (n = 61, age 20–46). ERFE concentrations across gestation (wks 8 – 42.1) were compared to Fe status and nutritional indicators (hemoglobin (Hb), serum ferritin (SF), soluble transferrin receptor (sTfR), total body Fe (TBI), TR-F index (sTfR/log(SF)), folate and vitamin B-12), as well as regulatory hormones (erythropoietin (EPO), hepcidin) and inflammatory markers (IL-6, C-reactive protein (CRP)). Results ERFE concentrations increased significantly across pregnancy in women carrying multiple fetuses (P &lt; 0.01), but did not change across pregnancy in the adolescents (P = 0.3). In both populations, 16% (n = 30) of women were anemic at midgestation (MG) and 24% (n = 75) at delivery. ERFE concentrations were significantly increased in anemic women at both MG (P = 0.02) and at delivery (P = 0.02). At MG (median 26 wks), ERFE was significantly positively associated with TfR (P &lt; 0.001) and EPO (P = 0.002). Maternal TfR, IL-6 and serum Fe were the strongest determinants of maternal MG ERFE, and explained 29% of variance in ERFE. At delivery (median 38 wks), ERFE was significantly positively associated with TfR (P &lt; 0.001) and EPO (P &lt; 0.001), which together explained 18% of variance in ERFE at delivery. ERFE was not significantly associated with hepcidin at either MG (P = 0.87) or delivery (P = 0.52). Conclusions ERFE was significantly higher in anemic women across pregnancy and, as expected, was positively associated with indicators of erythropoietic drive. ERFE however, was not significantly associated with hepcidin, possibly because hepcidin is regulated by multiple competing signals. More research is needed to understand the relationship between maternal ERFE and neonatal Fe status at birth. Funding Sources Funded by the NIH (NIDDK/NICHD).

For successful expansion of erythropoiesis, the activity of the hormone erythropoietin (EPO) must be coordinated with the supply of iron to erythroid precursors. Increased iron supply for erythropoiesis is ensured by the suppression of hepcidin, the iron-regulatory hormone produced by the liver. Low hepcidin levels allow greater absorption of dietary iron and greater mobilization of iron from the stores in the spleen and the liver. The mechanisms coordinating erythropoietic activity with iron delivery are not well understood. We recently identified erythroferrone as a new mediator of hepcidin suppression during stress erythropoiesis1. Erythroferrone (ERFE) is a member of the C1q/TNF-related protein (CTRP) family of metabolic mediators. ERFE is produced in response to EPO by erythroblasts of the bone marrow and spleen of mice. The induction of ERFE by EPO was dependent on Jak2/Stat5 signaling. Ex vivo treatment of human erythroblasts with EPO also resulted in a dramatic induction of ERFE expression. The essential role of ERFE in acute hepcidin suppression by erythropoiesis was demonstrated in ERFE-deficient mice. In contrast to wild-type mice which suppressed hepcidin ~10-fold within hours after hemorrhage or erythropoietin injection, no hepcidin suppression was observed in ERFE knockout mice within 24 h. As a consequence, ERFE-deficient mice exhibited delayed recovery of hemoglobin after hemorrhage or severe inflammation. Treatment of mice or hepatocytes with recombinant ERFE protein confirmed the hepcidin-suppressive activity of the protein. It remains to be seen whether administration of ERFE protein would be useful for the treatment of anemia of inflammation mediated by elevated hepcidin. In iron-loading anemias including β-thalassemia, hepcidin is chronically suppressed by the exuberant but ineffective erythropoietic activity. This is the cause of iron overload in untransfused thalassemia patients and may contribute to iron loading even in transfused patients. We found that ERFE expression is greatly increased in the bone marrow and spleen of mice with β-thalassemia intermedia (th3 model). Transgenic ablation of ERFE in th3 mice normalized hepcidin and partially corrected their iron overload. Although human studies of the role of ERFE in health and disease are clearly needed, ERFE is a promising candidate for the pathological suppressor of hepcidin in anemias with ineffective erythropoiesis. References: 1. Kautz L, Jung G, Valore EV, et al. Identification of erythroferrone as an erythroid regulator of iron metabolism. Nat Genet. 2014; 46: 678-684. Disclosures Nemeth: Intrinsic LifeSciences: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Merganser Biotech: Equity Ownership. Ganz:Intrinsic LifeSciences: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Keryx Pharma: Consultancy; Merganser Biotech: Consultancy, Equity Ownership.

BACKGROUND: Ineffective erythropoiesis in thalassemia alters iron homeostasis, predisposing to systemic iron overload. Successful allogeneic hematopoietic stem cell transplantation (HSCT) in thalassemia major corrects anemia, should eliminate ineffective erythropoiesis (IE) and normalize iron homeostasis (IH). Whether gene therapy (GT) will fully correct IE and IH is not known. This cross-sectional observational study evaluated the iron status of patients with beta thalassemia following HSCT or GT, and compared them with cohorts of patients with thalassemia intermedia (TI) or transfusion-dependent thalassemia (TDT) using recently introduced biomarkers along with imaging studies and other clinical assessments to better understand and characterize IE and IH across groups. METHODS: We evaluated a convenience sample of 29 participants with beta thalassemia (median age 25 years, IQR 21-35; females 55%; Asian 52%). Participants in the HSCT (n=6) and GT (n=10) groups were evaluated on average 116.5 and 46.9 months following cell infusion, respectively. TDT patients (n= 9) were evaluated pre-transfusion and off iron chelation for at least 7 days, and TI (n=4) were un-transfused or not transfused in &gt;3 years. Clinical lab assessments and MRI R2*/ T2* to assess heart and liver iron burden including post-processing, were performed using local clinical protocols. ELISAs for hepcidin, erythroferrone (Erfe) and GDF-15 were performed in a blinded manner. RESULTS: Median values for all IE and IH parameters tested were normal in the HSCT group, and were significantly lower than in all other groups. There were significant differences among all groups for hemoglobin (p=0.003), erythropoietin (Epo) (p=0.03), serum ferritin (SF) (p=0.01), transferrin (p=0.006), soluble transferrin receptor (sTfR) (p=0.02), serum hepcidin: serum ferritin (H:F) ratio (p=0.006), Erfe (p=0.001), GDF15 (p=0.003), and liver iron content (LIC) by MRI R2* (p=0.02). H:F ratio, a surrogate for predisposition to systemic iron loading, inversely correlated with Erfe (rs= -0.85, p&lt;0.0001), GDF15 (rs= -0.69, p=0.0001) and liver R2* (rs= -0.66, p=0.0004). In a multivariate analysis, adjusted for gender and race, H:F ratio and Epo levels predicted Erfe and GDF15 (p=0.05 and p=0.06; p=0.01 and p=0.05), respectively. Even after excluding GT patients that are not transfusion independent (N=2), SF, Epo, sTfR and hepcidin remain abnormal in the GT group, and there were no significant differences in these parameters between GT and TDT. However, novel biomarkers of IH and IE suggested lower ineffective erythropoiesis in GT compared to TDT (median (IQR) Erfe, 12 (11.6-25.2) vs. 39.6 (24.5-54.7), p=0.03; GDF15, 1909.9 (1389-4431) vs. 8906 (4421-12331), p=0.02), respectively. Erfe and GDF15 were also lower in GT compared to TI, however these differences did not reach statistical significance. There were no differences in hepcidin, ferritin, or H:F by race, however Erfe and GDF15 were significantly lower in Asians compared to non-Asians (p=0.006 and p=0.02, respectively). CONCLUSION: Nearly 4 years post infusion, most subjects with TDT treated with GT are transfusion independent with near normal hemoglobin, however, studies in this limited cohort using conventional measures suggest IE and IH improve, particularly when transfusion support is no longer needed, however they remain abnormal compared to HSCT recipients, who using these parameters appear to be cured. STfR did not detect differences, however GDF15 and Erfe were more sensitive assays that could demonstrate significant improvement in IE and IH with GT compared to TDT. Contribution to IE by uncorrected stem cell populations post GT cannot be determined. Transduction enhancement and other recent improvements to GT may yield different results. Longitudinal studies are needed to determine if thalassemia patients treated with GT will have ongoing IE predisposing to systemic iron overload. Disclosures Thompson: bluebird bio, Inc.: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Baxalta: Research Funding. Ganz:Intrinsic LifeSciences: Consultancy, Equity Ownership. Nemeth:Intrinsic LifeSciences: Consultancy, Equity Ownership; Silarus Therapeutics: Consultancy, Equity Ownership; Keryx: Consultancy; Ionis Pharmaceuticals: Consultancy; La Jolla Pharma: Consultancy; Protagonist: Consultancy.

Abstract Erythroferrone (ERFE) is an erythroblast-derived regulator of iron metabolism, and its production increases during stress erythropoiesis. ERFE decreases expression of the iron-regulatory hormone hepcidin to enhance iron availability for erythropoiesis 1. Pregnancy requires a substantial increase in iron availability to sustain a dramatic increase in maternal RBC volume and support fetal development. Whether maternal or fetal ERFE plays a role in regulating iron homeostasis during pregnancy is unknown. In humans, maternal ERFE concentrations were elevated in anemic pregnancies at mid gestation and delivery 2. To define the role of ERFE during iron-replete or iron-deficient pregnancy, we utilized Erfe transgenic (ETg) 3 and Erfe knockout (EKO) 1 mice. Maternal iron status of ETg, WT and EKO mice was altered by placing animals on adequate iron (100ppm) or low iron (4ppm) diet 2 weeks prior to and throughout pregnancy. ETg and WT dams were mated with WT sires to generate ETg and WT embryos while EKO dams were mated with EKO sires to generate EKO embryos. Analysis was performed at embryonic day 18.5. To examine the effect of pregnancy on ERFE expression, we compared non-pregnant females to WT dams at E18.5. Serum ERFE was mildly elevated from 0.01 to 0.2 ng/mL in iron-replete dams, but substantially elevated from 0.01 to 3.1 ng/mL in iron-deficient dams, similarly to human pregnancy 2. We next assessed iron and hematological parameters in pregnant dams with different Erfe genotypes. Under iron-replete conditions, all three groups had similar serum hepcidin, serum iron and hemoglobin concentrations, but ETg dams had 3-fold higher liver iron than WT and EKO dams, presumably because they are mildly iron-overloaded before pregnancy. On iron-deficient diet, maternal hepcidin was decreased in all three genotypes but more so in ETg dams; however, all three Erfe genotypes had similarly depleted liver iron stores, hypoferremia and anemia. MCV was the only parameter that was decreased in EKO compared to WT dams under both iron conditions. Overall, maternal ERFE played a minor role in regulation of maternal erythropoiesis and iron homeostasis, with the lack of ERFE resulting in smaller RBCs but not anemia. Among embryos, we observed a significant effect of Erfe genotype on embryo hepcidin. ETg embryos had significantly lower liver hepcidin compared to WT embryos under both iron-replete and iron-deficient conditions. Conversely, Erfe KO embryos had higher hepcidin compared to WTs under iron-deficient conditions, indicating that embryo ERFE regulates embryo hepcidin during pregnancy. Under iron-replete conditions however, all three embryo genotypes had similar hematologic parameters, and embryo liver iron was dependent on maternal iron levels, with both ETg and WT embryos from ETg dams having increased liver iron concentrations, indicating that embryo ERFE does not regulate placental iron transfer. Under iron-deficient conditions, there was no difference between ETg and WT embryos in hematological or iron parameters, and both genotypes developed iron deficiency and anemia. However, Erfe KO embryos, which had elevated hepcidin, had maldistribution of iron and worse anemia. EKO embryo liver iron concentrations were 6-fold higher compared to WT iron-deficient embryos, whereas hemoglobin was significantly decreased compared to WT iron-deficient embryos. These findings indicate that under iron-limiting conditions, embryo ERFE is important for the suppression of embryo hepcidin to ensure iron redistribution for embryo erythropoiesis. In summary, during iron replete pregnancy, ERFE plays a minor role in maternal and fetal iron homeostasis and erythropoiesis. However, in response to iron-deficiency anemia during pregnancy, ERFE is important for the redistribution of iron within the embryo to support embryo erythropoiesis. 1Kautz L et al, Nat Genet, 2014 2Delaney K et al, Curr Dev Nutr, 2020 3Coffey R et al, Blood, 2020 Disclosures Ganz: Ambys: Consultancy; Sierra Oncology: Consultancy, Research Funding; Rockwell: Consultancy; Pharmacosmos: Consultancy; Ionis: Consultancy; Protagonist: Consultancy; Intrinsic LifeSciences: Consultancy; RallyBio: Consultancy; Silence Therapeutics: Consultancy; Silarus Pharma: Consultancy; Alnylam: Consultancy; American Regent: Consultancy; Disc Medicine: Consultancy, Membership on an entity's Board of Directors or advisory committees; AstraZenecaFibrogen: Consultancy; Global Blood Therapeutics: Consultancy; Gossamer Bio: Consultancy; Akebia: Consultancy, Honoraria. Nemeth: Silarus Pharma: Consultancy; Intrinsic LifeSciences: Consultancy; Protagonist: Consultancy; Vifor: Consultancy; Ionis: Consultancy.

Abstract BACKGROUND: Anemia is the most common manifestation of low-risk myelodysplastic syndromes (MDS). Iron-overload in MDS can occur before transfusion dependence in the context of ineffective erythropoiesis. Significantly lower hepcidin levels have been described in patients with sideroblastic refractory anemia compared to higher risk MDS, promoting inadequate iron absorption that leads to higher iron overload. Erythroferrone (ERFE) is a hormone that stimulates erythropoiesis and regulates iron homeostasis; in physiological conditions, is stimulated by erythropoietin and increases iron absorption inhibiting hepcidin. There are no studies describing the activity of ERFE in MDS. The objective of this study was to describe the relationship among hepcidin, ERFE and iron overload in 31 patients with low-risk MDS. METHODS: 50 samples were analized, 31 from patients (16 males, 17 females) with low-risk MDS: 10 low IPSS-R and 21 very-low IPSS-R; and 19 from healthy controls. 13 patients showed severe anemia with transfusion dependence, 4 patients received only erythropoiesis stimulating agents (ESA) and 14 patients did not receive any treatment for the anemia. Patient characteristics are summarized in table 1. Hepcidin levels were measured using the DRG Hepcidin 25 (bioactive) HS ELISA Kit (DRG Diagnostics GmbH), and ERFE was measured with the FAM132B (Human) OKEH02395 ELISA kit (Aviva Systems). For the analysis, two groups of patients were considered: 13 with severe and transfusion dependent anemia and 18 with mild/moderate anemia. RESULTS: Patients with severe anemia showed higher serum ferritin levels (median 2143ng/mL vs 204ng/mL, p<0.001) compared to patients without transfusion dependence. Hepcidin levels were significantly higher in patients with transfusion dependent anemia (mean 59.85 vs 16.11ng/mL, p=0.001) compared to patients with transfusion independence, and were also higher in these last patients compared to healthy controls (mean 16.11 vs 10.6ng/mL, p<0.001). Regarding ERFE, patients with transfusion dependent anemia showed significantly higher ERFE levels (mean 281.92 vs. 62.83pg/mL, p=0.016) than patients with mild/moderate anemia. However, there were no significant differences between patients with mild/moderate anemia and healthy controls. There was no correlation between hepcidin and ERFE levels (p=0.46). CONCLUSIONS: To the best of our knowledge, this is the first simultaneous analysis of hepcidine and ERFE in MDS. Patients with severe anemia showed significantly higher ERFE levels compared to those with moderate anemia, suggesting a higher erythropoietic stimulus. Patients with severe anemia showed significantly superior hepcidin levels, hindering iron absorption in situations of massive iron overload. Accordingly, ERFE did not show negative correlation with hepcidin in either cohort, supporting the abnormal iron metabolism in MDS. Larger studies are required to define the relationship between hepcidin and ERFE in low-risk MDS. Disclosures No relevant conflicts of interest to declare.

Цель. Оценить взаимосвязь между гепцидином, растворимым рецептором трансферрина (sTfR) и показателями обмена железа, концентрацией гемоглобина и числом эритроцитов у ревматических пациентов.Материалы и методы. Обследованы 63 пациента ревматологического профиля: 26 мужчин (45 (36–54,9) лет), 37 женщин (49 (38–60) лет). Пациенты разделены на две группы: 1-я группа – 41 пациент с анемией, 2-я группа (контрольная) – 22 пациента без анемии. Выполнен сравнительный анализ показателей гемограммы, обмена железа (железо, ферритин, трансферрин, общая железосвязывающая способность сыворотки крови – ОЖСС, коэффициент насыщения трансферрина железом – КНТ), гепцидина, растворимого рецептора трансферрина (sTfR), С-реактивного белка (СРБ). Выполнен корреляционный анализ между гепцидином, sTfR и показателями гемограммы и обмена железом.Результаты. У пациентов с анемией в сравнении с контрольной группой выше концентрации гепцидина (504,9 (23,5–916,5) и 232(0,0–858) нг/мл), sTfR (8,6 (3,9–7,1) и 2,2 (1,5–3,1) нмоль/л),а также ферритина (292,7 (146,1–335,1) и 78,5 (36–90,7) мкг/л), СРБ (59,4 (10,9–100,2)и 4,6 (1,2–5,8) мг/л). Для железа, ОЖСС, КНТ, трансферрина не выявлено межгрупповых различий (p>0,05). Выявлена корреляция между числом эритроцитов и гепцидином (r=–0,5), sTfR (r=–0,5). Выявлена корреляция между концентрацией гемоглобина и гепцидином (r=–0,7), sTfR (r=–0,7). Для концентрации гепцидина установлена прямая взаимосвязь с ферритином (r=0,6) и СРБ (r=0,3) и обратная взаимосвязь с ОЖСС (r=–0,6) и трансферрином (r=–0,6). Не выявлено взаимосвязи между гепцидином и железом, КНТ. В отношении концентрации sTfR установлена прямая корреляционная связь с ферритином (r=0,4) и СРБ (r=0,3) и обратная корреляционная связь с железом (r=–0,6) и КНТ (r=–0,5). Не выявлено взаимосвязи между sTfR и ОЖСС, трансферрином.Влияние гепцидина и растворимого рецептора трансферринана развитие анемии хронических заболеваний у ревматических пациентов. Заключение. Показан многокомпонентный генез анемии у ревматических пациентов. Установлено значение увеличения секреции гепцидина, sTfR, нарушений в обмене железа на развитие анемии. Установлено супрессорное влияние гепцидина на выработку клеток эритрона. Доказано слабое влияние воспаления на концентрацию sTfR. Purpose. To assess the relationship between hepcidin, soluble transferrin receptor (sTfR), and indicators of iron metabolism, hemoglobin concentration, and erythrocyte number in rheumatic patients.Materials and Methods. The study involved 63 rheumatic patients: 26 men (45 (36–54.9) years old), 37 women (49 (38–60) years old). The patients were divided into two groups: group 1 – 41 patients with anemia, group 2 (control) – 22 patients without anemia. Comparative analysis of hemogram parameters, iron metabolism (iron, ferritin, transferrin, total iron-binding capacity of blood serum – TIBC, iron transferrin saturation index (TSI), hepcidin, soluble transferrin receptor (sTfR), C-reactive protein (CRP) was performed. Correlation analysis was performed between hepcidin, sTfR, and hemogram and iron metabolism parameters.Results. In patients with anemia, the concentration of hepcidin (504.9 (23.5–916.5) and 232 (0.0–858) ng/ml), sTfR (8.6 (3.9–7.1) and 2.2 (1.5–3.1) nmol/L), ferritin (292.7(146.1–335.1) and78.5(36–90.7) μg/L), CRP (59.4 (10.9–100.2) and 4.6 (1.2–5.8) mg/L) is higher in comparison with the control group. There were no intergroup differences for iron, TIBS, CST, transferrin (p>0.05). The correlation was found between the number of erythrocytes and hepcidin (r=–0.5), sTfR (r=–0.5). The correlation was found between the concentration of hemoglobin and hepcidin (r=–0.7), sTfR (r=–0.7). For the concentration of hepcidin, a direct relationship with ferritin (r=0.6) and CRP (r=0.3) and the inverse relationship with TIBC (r=–0.6) and transferrin (r=–0.6) were revealed. No relationship was found between hepcidin and iron, TSI. In relation to the concentration of sTfR, a direct correlation was revealed with ferritin (r=0.4) and CRP (r=0.3) and the inverse correlation with iron (r=–0.6) and CST (r=–0.5). No relationship was found between sTfR and TIBC, transferrin Conclusion. There was showed the multicomponent genesis of anemia in rheumatic patients. The significance of the increase of the secretion of hepcidin, sTfR, disorders of iron metabolism for the development of anemia was revealed. The suppressive effect of hepcidin on the production of erythron cells was also revealed. A weak effect of inflammation on the concentration of sTfR was proved.

Aim. To study the eff ect of hepcidin, soluble transferrin receptor (sTfR ), and cytokines on iron metabolism and the development of anemia in rheumatologic patients, to propose a working version of the classifi cation of anemia of chronic diseases (ACD) according to the major nosotropic factor.Material and methods. 126 patients with rheumatic disease, 34 men (45.8 (36–54.9) years old), 92 women (49.5 (38–60) years old) were examined. Group 1 included 41 patients with ACD. Group 2 included 29 patients with the combination of ACD and IDA and 34 patients with iron defi ciency anemia (IDA). Group 3 included 34 patients with IDA and 29 — with the combination of ACD and IDA. Control group included 22 patients without anemia. Comparative analysis between groups with and without anemia and correlation analysis of hemogram parameters, iron metabolism, C-reactive protein (CRP), hepcidin, sTfR , interleukin-6 (IL-6), IL-1β, IL-10, interferon gamma (INF-γ) and tumor necrosis factor alpha (TNF-α) were performed.Results. In the ACD group, the concentrations of hepcidin, ferritin, CRP, IL-6 were increased in comparison with other groups. The correlation was revealed between erythrocytes, hemoglobin and IL-6 (r = −0.3 and −0.6), IL-10 (r = −0.4 and −0.4), INF-γ (r = −0.4 and −0.3), TNF-α (r = −0.3 and −0.3), hepcidin (r = −0.5 and −0.7), sTfR (r = −0.5 and −0.7). Dependence was shown between IL-6 and iron (r = –0.6), transferrin saturation index (TSI) (r = −0.5), ferritin (r = −0.5), CRP (r = 0.5), between TNF-α and TIBС (r = −0.6), transferrin (r = −0.6), ferritin (r = −0.7), between IL-1β and TIBC, ferritin, transferrin (r = −0.4). The correlation was noted between hepcidin and IL-6 (r = 0.5), IL-10 (r = 0.4), between sTfR and IL-6 (r = 0.4), IL-10 (r = 0.6), INF-γ (r = 0.4).Conclusion. The multicomponent genesis of anemia in patients with rheumatologic disease was detected. The signifi cance of disorders in iron metabolism, the eff ect of hepcidin, sTfR and cytokines on the development of anemia was found. A working version of ACD classifi cation (with a predominant iron defi ciency, with violations of the regulatory mechanisms of erythropoiesis, with insuffi cient production of erythropoietin) has been put forward.

Il ferro è un elemento essenziale per tutti gli organismi viventi ed è coinvolto in una varietà di funzioni vitali, tra cui il metabolismo energetico cellulare, la respirazione anaerobica, la sintesi di emoglobina e nucleotidi. Tuttavia, il ferro libero è altamente reattivo e tossico grazie alla sua capacità di accettare e donare elettroni e generare radicali liberi derivati dall'ossigeno (Reactive Oxygen Species-ROS). Pertanto, il contenuto di ferro nel corpo deve essere strettamente regolato. L'epcidina è il principale regolatore dell'omeostasi del ferro, controlla i livelli plasmatici di ferro e il ferro corporeo totale e la sua alterazione può portare sia a carenza di ferro (alti livelli di epcidina) sia a sovraccarico di ferro (bassi livelli di epcidina). L'eritroferrone (ERFE) è il principale regolatore eritroide dell'epcidina. L'aumento dei livelli di ERFE sopprime la sintesi di epcidina, mobilitando così le riserve di ferro cellulare per l'uso nella sintesi di eme ed emoglobina. Nell'eritropoiesi inefficace, la sovrapproduzione di ERFE da parte di una popolazione espansa di eritroblasti, sopprime l'epcidina e causa il sovraccarico di ferro. Il recettore solubile della transferrina (sTfR) è una forma scissa del recettore 1 della transferrina tissutale (TfR1). sTfR fornisce informazioni sullo stato funzionale del ferro e i suoi livelli sono aumentati in caso di carenza di ferro (ID) e quando viene stimolata l'eritropoiesi. Lo scopo principale di questo studio era indagare i determinanti del metabolismo del ferro a livello di popolazione, mediante l'analisi delle concentrazioni sieriche di epcidina, ERFE e sTfR in 4644 soggetti della popolazione della Val Venosta, una popolazione omogenea in Alto Adige-Italia, come parte di un progetto più ampio istituito nel 2011 per lo studio delle basi genetiche delle comuni condizioni croniche associate all'invecchiamento umano e della loro interazione con lo stile di vita e fattori ambientali nella popolazione generale dell'Alto Adige (studio CHRIS). La misurazione dell'epcidina sierica (isoforme 20, 24 e 25), ERFE e sTfR è stata eseguita nel Laboratorio dei Disturbi del Ferro presso il LURM (Laboratorio Universitario di Ricerca Medica), mediante un approccio LC-MS / MS per l'epcidina e tecniche ELISA per ERFE e sTfR.6 L'epcidina-25 ha confermato una variazione dipendente dall'età e dal sesso, mentre l'ERFE ha mostrato una variazione meno significativa. Le analisi di correlazione dell'epcidina-25 hanno mostrato che essa si correla di più con la ferritina che con la saturazione sierica di ferro e transferrina, mentre ERFE ha mostrato una relazione negativa con l'emoglobina e i globuli rossi. I risultati qui presentati, come la definizione di un range di riferimento aggiornato per i livelli di epcidina-25 ed ERFE e lo studio della variazione di epcidina ed ERFE in diverse condizioni, potrebbero avere applicazioni cliniche, oltre a sottolineare l'utilità di questi biomarcatori emergenti per la valutazione dello stato del ferro negli approcci diagnostici.
Iron is an essential element for all living organisms, and it is involved in a variety of vital functions including cellular energy metabolism, anaerobic respiration, synthesis of hemoglobin and nucleotides. On the other hand, free iron is highly reactive and toxic due to its capability to accept and donates electrons and generate oxygen-derived free radicals (Reactive Oxygen Species-ROS). Thus, iron content in the body needs to be tightly regulated. Hepcidin is the principal iron homeostasis regulator by controlling plasma iron levels and total body iron, and its alteration can lead either functional iron deficiency (high hepcidin levels) or iron overload (low hepcidin levels). Erythroferrone (ERFE) is the main erythroid regulator of hepcidin. Increased ERFE levels suppress hepcidin synthesis, thereby mobilizing cellular iron stores for use in heme and hemoglobin synthesis. In ineffective erythropoiesis, pathological overproduction of ERFE by an expanded population of erythroblasts suppresses hepcidin and causes iron overload. Soluble transferrin receptor (sTfR) is a cleaved form of the tissue transferrin receptor 1 (TfR1). sTfR gives information on the functional iron status and its levels are increased in iron deficiency (ID) and when erythropoiesis is stimulated. The main aim of this study was to investigate iron metabolism determinants at population level by the analysis of serum hepcidin, ERFE and sTfR concentrations in 4644 subjects of the Val Venosta population, a homogeneous population in South Tyrol-Italy, as part of a larger project established in 2011 for the investigation of the genetic basis of common chronic conditions associated with human ageing and their interaction with life-style and environmental factors in the general population of South Tyrol (The CHRIS study). Serum hepcidin (20, 24 and 25 isoforms), ERFE and sTfR measurement was performed in the Laboratory of Iron Disorders at the LURM (University Laboratory for Medical Research), by means of an LC-MS/MS approach for hepcidin, and ELISA techniques for ERFE and sTfR. Hepcidin-25 confirmed an age and sex dependent variation, while ERFE showed a less significant age- and gender-dependent variation. Hepcidin-25 correlation 4 analyses showed that it correlates more with ferritin than with serum iron and transferrin saturation, whereas ERFE showed a negative relationship with hemoglobin and red blood cells. The results here presented, such as the establishment of an updated reference range for hepcidin-25 and ERFE levels and the investigation of hepcidin and ERFE variation in different conditions, could have clinical applications, as well as underling the usefulness of these emergent biomarkers for the assessment of human iron status in diagnostic approaches.