RESUMEN
Obstructive sleep apnea (OSA) patients exhibit different degrees of cognitive impairment, which is related to the activation of reactive oxygen species (ROS) production by chronic intermittent hypoxia (CIH) and the deposition of iron in the brain. As a central regulator of iron homeostasis, whether hepcidin is involved in OSA-induced cognitive impairment has not been clarified. In order to simulate OSA, we established the mouse model by reducing the percentage of inspired O2 (FiO2) from 21% to 5%, 20 times/h for 8 h/day. We found hepcidin was rising during CIH, along with increasing iron levels and neuron loss. Then, we constructed a mouse with astrocyte-specific knockdown hepcidin gene (shHamp). During CIH exposure, the shHamp mice showed a lower level of total iron and neuronal iron in the hippocampus, via stabilizing ferroportin 1 (FPN1) and decreasing L-ferritin (FTL) levels, when compared with wild-type (WT) mice. Furthermore, the shHamp mice showed a decrease of ROS by downregulating the elevated NADPH oxidase (NOX2) and 4-hydroxynonenal (4-HNE) levels mediated by CIH. In addition, the shHamp mice presented improved cognitive deficit by improving synaptic plasticity and BDNF expression in the hippocampus when subjected to CIH. Therefore, our data revealed that highly expressed hepcidin might promote the degradation of FPN1, resulting in neuronal iron deposition, oxidative stress damage, reduced synaptic plasticity, and impaired cognitive performance during CIH exposure.
Asunto(s)
Hepcidinas/metabolismo , Hipoxia , Aldehídos/metabolismo , Animales , Apoptosis , Modelos Animales de Enfermedad , Ferritinas/metabolismo , Hepcidinas/antagonistas & inhibidores , Hepcidinas/genética , Hipocampo/metabolismo , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/metabolismo , Plasticidad Neuronal , Estrés Oxidativo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Apnea Obstructiva del Sueño/metabolismo , Apnea Obstructiva del Sueño/patología , Proteína X Asociada a bcl-2/metabolismoRESUMEN
BACKGROUND: Patients with CKD frequently have anemia that results from iron-restricted erythropoiesis and inflammation. Anemia of CKD is currently managed with iron supplements and erythropoiesis-stimulating agents (ESAs) to promote erythropoiesis and with RBC transfusion in severe cases. Hyporesponse to ESAs, or the need for larger than usual doses to attain a given hemoglobin (Hb) level, is associated with increased morbidity and mortality and presents a pressing clinical challenge, particularly for patients on dialysis. This paper reviews ESA hyporesponse and potential new therapeutic options in the management of anemia of CKD. SUMMARY: The most common causes of ESA hyporesponse include iron deficiency and inflammation, and to a lesser degree, secondary hyperparathyroidism, inadequate dialysis, malnutrition, and concomitant medications. Management of ESA hyporesponse is multipronged and involves treating low level infections, ensuring adequate nutrition, and optimizing iron status and dialysis modality, although some patients can remain refractory. Inflammation directly increases production and secretion of hepcidin, contributes to an impaired response to hypoxia, and suppresses proliferation of erythroid progenitors. Coordination of renal and hepatic erythropoietin (EPO) production and iron metabolism is under the control of hypoxia-inducible factors (HIF), which are in turn regulated by HIF-prolyl hydroxylases (HIF-PHs). HIF-PHs and hepcidin are therefore attractive potential drug targets particularly in patients with ESA hyporesponse. Several oral HIF-PH inhibitors have been evaluated in patients with anemia of CKD and have been shown to increase Hb and reduce hepcidin regardless of inflammation, iron status, or dialysis modality. These sustained effects are achieved through more modest increases in endogenous EPO compared with ESAs. Key Messages: Treatments that address ESA hyporesponse remain a significant unmet clinical need in patients with anemia of CKD. New therapies such as HIF-PH inhibitors have the potential to address fundamental aspects of ESA hyporesponse and provide a new therapeutic option in these patients.
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Anemia/terapia , Inhibidores Enzimáticos/uso terapéutico , Hematínicos/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Anemia/etiología , Hemoglobinas/metabolismo , Hepcidinas/antagonistas & inhibidores , Humanos , Hiperparatiroidismo Secundario/complicaciones , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Infecciones/complicaciones , Infecciones/tratamiento farmacológico , Inflamación/complicaciones , Hierro/uso terapéutico , Deficiencias de Hierro/complicaciones , Deficiencias de Hierro/tratamiento farmacológico , Estado Nutricional , Insuficiencia Renal Crónica/terapiaRESUMEN
Iron is an essential element for the mammalian body however, its homeostasis must be regulated accurately for appropriate physiological functioning. Alterations in physiological iron levels can lead to moderate to severe iron disorders like chronic and acute iron deficiency (anemia) or iron overload. Hepcidin plays an important role in regulating homeostasis between circulating iron and stored iron in the cells as well as the absorption of dietary iron in the intestine. Inflammatory disorders restrict iron absorption from food due to increased circulating levels of hepcidin. Increased production of hepcidin causes ubiquitination of ferroportin (FPN) leading to its degradation, thereby retaining iron in the spleen, duodenal enterocytes, macrophages, and hepatocytes. Hepcidin inhibitors and antagonists play a consequential role to ameliorate inflammation-associated anemia. Many natural and synthesized compounds, able to reduce hepcidin expression during inflammation have been identified in recent years. Few of which are currently at various phases of clinical trial. This article comprises a comprehensive review of therapeutic approaches for the efficient treatment of anemia associated with inflammation. Many strategies have been developed targeting the hepcidin-FPN axis to rectify iron disorders. Hepcidin modulation with siRNAs, antibodies, chemical compounds, and plant extracts provides new insights for developing advanced therapeutics for iron-related disorders. Hepcidin antagonist's treatment has a high potential to improve iron status in patients with iron disorders, but their clinical success needs further recognition along with the identification and application of new therapeutic approaches.
Asunto(s)
Anemia , Hepcidinas , Inflamación , Anemia/complicaciones , Anemia/tratamiento farmacológico , Ensayos Clínicos como Asunto , Hepcidinas/antagonistas & inhibidores , Humanos , Inflamación/etiología , Deficiencias de HierroRESUMEN
Hepcidin is the only known hormone negatively regulates systemic iron availability, its excess contributes to anemia of chronic disease (ACD).Heparin has been shown to be an efficient hepcidin inhibitor both in vitro and in vivo, but its powerful anticoagulant activity limits this therapeutic application. To this end, heparin-iron complex was prepared by electrostatic interaction and/or coordination between heparin and dihydroxy iron solution ([Fe(OH)2]+) under the condition of ultrasonic assisted. We assessed the anticoagulant activity of heparin-iron in vitro and vivo by sheep plasma, chromogenic substrate method and tail-bleeding in mice, respectively. Anti-hepcidin effect of heparin-iron was detected in HepG2 cell and LPS induced acute inflammation mice by qRT-PCR and ELISA. Turpentine-induced anemia mice were established to evaluate the effect of heparin-iron in ACD. Mice were treated with heparin-iron for 4 weeks. The results indicated that heparin-iron has significantly reduced anticoagulant activity in vitro and in vivo, strongly decreases hepcidin mRNA and IL-6 induced high level of secreted hepcidin in HepG2 cell. Heparin-iron was also found to cause a reduction on hepcidin expression through BMP/SMAD and JAK/STAT3 pathways in LPS induced acute inflammation model in mice. In ACD mice, heparin-iron could lower elevated serum hepcidin and improve anemia. These findings demonstrated low anticoagulant heparin-iron has potential applications for the treatment of ACD with high hepcidin levels.
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Anemia/prevención & control , Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , Compuestos Férricos/farmacología , Heparina/farmacología , Hepcidinas/antagonistas & inhibidores , Compuestos de Hierro/farmacología , Hígado/efectos de los fármacos , Anemia/etiología , Anemia/metabolismo , Animales , Proteínas Morfogenéticas Óseas/metabolismo , Modelos Animales de Enfermedad , Femenino , Compuestos Férricos/uso terapéutico , Células Hep G2 , Heparina/análogos & derivados , Heparina/uso terapéutico , Hepcidinas/genética , Hepcidinas/metabolismo , Humanos , Inflamación/complicaciones , Compuestos de Hierro/análogos & derivados , Quinasas Janus/metabolismo , Hígado/metabolismo , Ratones Endogámicos BALB C , Factor de Transcripción STAT3/metabolismo , Oveja Doméstica , Transducción de Señal , Proteínas Smad/metabolismo , TrementinaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Silkworm faeces are the dry faeces of the insect Bombyx mori (Linnaeus) and have historically been used in traditional Chinese medicine to treat blood deficiency and rheumatic pain. Silkworm faeces extract (SFE) is derived from silkworm faeces. AIM OF THE STUDY: Clinical observations of patients in the Department of Nephrology have shown that SFE effectively improves renal anaemia. However, the molecular mechanism remains unclear. This article mainly explores the regulatory effects of SFE on erythropoietin (EPO) and hepcidin to identify the molecular mechanism of SFE. MATERIALS AND METHODS: A rat model of renal anaemia was established by feeding rats food containing 0.75% adenine. SFE was orally administered to the rats, while recombinant human erythropoietin (rhEPO) was used as a positive control drug. Haematological parameters and inflammation levels were compared between rats from each group, and pathological kidney sections from each rat were observed. The serum EPO and hepcidin levels were detected using enzyme-linked immunosorbent assay (ELISA) kits, while Western blot analyses were performed to detect the levels of proteins involved in the EPO-related hypoxia-inducible factor 2α (HIF-2α)/prolyl hydroxylase 2 (PHD2) signalling pathway and hepcidin-related BMP6/SMAD4 and interleukin-6 (IL-6)/STAT3 signalling pathways. RESULTS: SFE significantly ameliorated haematological parameters, renal function, and inflammation levels in the rats. A mechanistic study showed that SFE promoted EPO expression by upregulating HIF-2α expression and inhibiting the expression of NF-κB and GATA2 both in vivo and in vitro. In particular, SFE inhibited PHD2 expression, resulting in a decrease in the enzymatic reaction of HIF-2α to increase EPO expression. Furthermore, SFE inhibited hepcidin expression by blocking the BMP6/SMAD4 and IL-6/STAT3 pathways. CONCLUSIONS: SFE regulated iron metabolism by inhibiting hepcidin and simultaneously promoted EPO synthesis to improve renal anaemia in rats.
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Anemia/prevención & control , Bombyx/metabolismo , Heces/química , Enfermedades Renales/complicaciones , Adenina , Anemia/etiología , Animales , Modelos Animales de Enfermedad , Eritropoyetina/administración & dosificación , Eritropoyetina/metabolismo , Hepcidinas/antagonistas & inhibidores , Hepcidinas/metabolismo , Humanos , Hierro/metabolismo , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Salmonellosis and listeriosis together accounted for more than one third of foodborne illnesses in the United States and almost half the hospitalizations for gastrointestinal diseases in 2018 while tuberculosis afflicted over 10 million people worldwide causing almost 2 million deaths. Regardless of the intrinsic virulence differences among Listeria monocytogenes, Salmonella enterica and Mycobacterium tuberculosis, these intracellular pathogens share the ability to survive and persist inside the macrophage and other cells and thrive in iron rich environments. Interferon-gamma (IFN-γ) is a central cytokine in host defense against intracellular pathogens and has been shown to promote iron export in macrophages. We hypothesize that IFN-γ decreases iron availability to intracellular pathogens consequently limiting replication in these cells. In this study, we show that IFN-γ regulates the expression of iron-related proteins hepcidin, ferroportin, and ferritin to induce iron export from macrophages. Listeria monocytogenes, S. enterica, and M. tuberculosis infections significantly induce iron sequestration in human macrophages. In contrast, IFN-γ significantly reduces hepcidin secretion in S. enterica and M. tuberculosis infected macrophages. Similarly, IFN-γ-activated macrophages express higher ferroportin levels than untreated controls even after infection with L. monocytogenes bacilli; bacterial infection greatly down-regulates ferroportin expression. Collectively, IFN-γ significantly inhibits pathogen-associated intracellular iron sequestration in macrophages and consequently retards the growth of intracellular bacterial pathogens by decreasing iron availability.
Asunto(s)
Interferón gamma/farmacología , Hierro/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Transporte Biológico Activo/efectos de los fármacos , Proteínas de Transporte de Catión/metabolismo , Ferritinas/metabolismo , Hepcidinas/antagonistas & inhibidores , Hepcidinas/metabolismo , Interacciones Microbiota-Huesped/efectos de los fármacos , Interacciones Microbiota-Huesped/inmunología , Interacciones Microbiota-Huesped/fisiología , Humanos , Inmunidad Innata , Interferón gamma/inmunología , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/patogenicidad , Macrófagos/efectos de los fármacos , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/patogenicidad , Proteínas Recombinantes/farmacología , Salmonella enterica/crecimiento & desarrollo , Salmonella enterica/patogenicidad , Células THP-1RESUMEN
Hepcidin peptide is crucial in the regulation of systemic iron availability controlling its uptake from the diet and its release from the body storage tissues. Hepcidin dysregulation causes different human disorders ranging from iron overload (e.g. hemochromatosis) to iron deficiency (e.g. anemia). Hepcidin excess is common in the Anemia of Chronic Diseases or Anemia of Inflammation and in the genetic form of anemia named IRIDA; the pharmacological downregulation of hepcidin in these disorders could improve the anemia. Commercial heparins were shown to be strong inhibitors of hepcidin expression, by interfering with BMP6/SMAD pathway. The non-anti-coagulant heparins, modified to abolish the anti-thrombin binding site, were equally potent and could be used to improve iron status. To perform its anti-hepcidin activity heparin needs 2O- and 6O-sulfation and an average molecular weight (MW) up to 4000-8000 Dalton, depending on the sulfation level. The pentosane polysulfate (PPS), which shares with heparin a high degree of sulfation, is a compound with low anti-coagulant activity that is already in use for pharmaceutical treatment. In the present work we analyzed the anti-hepcidin activity of PPS in vitro and in vivo. We found that it acts as a strong inhibitor of hepcidin expression in HepG2 cells with an effect already visible after 2-3 h of treatment. It also suppressed hepcidin in mice in a dose dependent manner after 3 h and with a significant redistribution of systemic iron without evident side effects. PPS is also able to abolish the LPS dependent hepcidin upregulation similarly to that showed for heparin derivatives. These results suggest PPS as an interesting compound to control hepcidin in vivo.
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Expresión Génica/efectos de los fármacos , Hepcidinas/antagonistas & inhibidores , Poliéster Pentosan Sulfúrico/farmacología , Administración Oral , Animales , Expresión Génica/inmunología , Células Hep G2 , Hepcidinas/sangre , Hepcidinas/genética , Humanos , Inyecciones Subcutáneas , Hígado/efectos de los fármacos , Hígado/inmunología , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Poliéster Pentosan Sulfúrico/administración & dosificaciónRESUMEN
CONTEXT: Dapagliflozin and other SGLT2 inhibitors are known to increase hematocrit, possibly due to its diuretic effects and hemoconcentration. OBJECTIVE: Since type 2 diabetes is a proinflammatory state and since hepcidin, a known suppressor of erythropoiesis, is increased in proinflammatory states, we investigated the possibility that dapagliflozin suppresses hepcidin concentrations and thus increases erythropoiesis. DESIGN: Prospective, randomized, and placebo-controlled study. SETTING: Single endocrinology center. PATIENTS: Fifty-two obese type 2 diabetes patients. INTERVENTION: Patients were randomized (1:1) to either dapagliflozin (10 mg daily) or placebo for 12 weeks. Blood samples were collected before and after treatments and serum, plasma, and mononuclear cells (MNC) were prepared. MAIN OUTCOME MEASURE: Hepcidin and other hematopoietic factors. RESULTS: Following dapagliflozin treatment, there was a significant fall in HbA1c and a significant increase in hemoglobin concentration and hematocrit. Dapagliflozin treatment significantly reduced circulating hepcidin and ferritin concentrations while causing a significant increase in levels of the hepcidin inhibitor, erythroferrone, and a transient increase in erythropoietin. Additionally, dapagliflozin increased plasma transferrin levels and expression of transferrin receptors 1 and 2 in MNC, while there was no change in the expression of the iron cellular transporter, ferroportin. Dapagliflozin treatment also caused a decrease in hypoxia-induced factor-1α expression in MNC while it increased the expression of its inhibitor, prolyl hydroxylase-2. There were no significant changes in any of these indices in the placebo group. CONCLUSIONS: We conclude that dapagliflozin increases erythropoiesis and hematocrit through mechanisms that involve the suppression of hepcidin and the modulation of other iron regulatory proteins.
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Compuestos de Bencidrilo/uso terapéutico , Biomarcadores/análisis , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Eritropoyesis/efectos de los fármacos , Glucósidos/uso terapéutico , Hepcidinas/uso terapéutico , Obesidad/fisiopatología , Antiinfecciosos/química , Antiinfecciosos/uso terapéutico , Glucemia/análisis , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Hepcidinas/antagonistas & inhibidores , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéuticoRESUMEN
Hepcidin (HAMP) synthesis is suppressed by erythropoiesis to increase iron availability for red blood cell production. This effect is thought to result from factors secreted by erythroid precursors. Growth differentiation factor 11 (GDF11) expression was recently shown to increase in erythroid cells of ß-thalassaemia, and decrease with improvement in anaemia. Whether GDF11 regulates hepatic HAMP production has never been experimentally studied. Here, we explore GDF11 function during erythropoiesis-triggered HAMP suppression. Our results confirm that exogenous erythropoietin significantly increases Gdf11 as well as Erfe (erythroferrone) expression, and Gdf11 is also increased, albeit at a lower degree than Erfe, in phlebotomized wild type and ß-thalassaemic mice. GDF11 is expressed predominantly in erythroid burst forming unit- and erythroid colony-forming unit- cells during erythropoiesis. Exogeneous GDF11 administration results in HAMP suppression in vivo and in vitro. Furthermore, exogenous GDF11 decreases BMP-SMAD signalling, enhances SMAD ubiquitin regulatory factor 1 (SMURF1) expression and induces ERK1/2 (MAPK3/1) signalling. ERK1/2 signalling activation is required for GDF11 or SMURF1-mediated suppression in BMP-SMAD signalling and HAMP expression. This research newly characterizes GDF11 in erythropoiesis-mediated HAMP suppression, in addition to ERFE.
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Proteínas Morfogenéticas Óseas/metabolismo , Factores de Diferenciación de Crecimiento/metabolismo , Hepcidinas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Proteínas Morfogenéticas Óseas/biosíntesis , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/farmacología , Eritropoyesis/fisiología , Eritropoyetina/farmacología , Factores de Diferenciación de Crecimiento/biosíntesis , Factores de Diferenciación de Crecimiento/genética , Factores de Diferenciación de Crecimiento/farmacología , Células Hep G2 , Hepatocitos/metabolismo , Hepcidinas/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos C57BL , Hormonas Peptídicas/biosíntesis , Hormonas Peptídicas/genética , Proteínas Recombinantes/farmacología , Proteínas Smad/metabolismoRESUMEN
Dysregulation of metabolism and utilization of iron can lead to the development and maintenance of anemia of CKD. Anemia is prevalent among patients with CKD. The markers of iron sufficiency or availability of iron are far from perfect which results in inaccurate diagnosis and treatment of anemia with poor outcomes. Hepcidin, a 25 amino acid peptide produced by the hepatocytes, has emerged as the key regulator of uptake and release of iron in the tissues to maintain a steady supply of iron to erythron and other tissues while avoiding higher levels of iron that could be detrimental to the organs. Hepcidin itself is regulated by the supply of iron, the need for erythropoiesis, and the state of inflammation. Alterations in hepcidin levels are associated with restricted erythropoiesis, anemia, and iron overload. Discovery of hepcidin and elucidation of its mechanism of action and consequences of its upregulation and suppression have unraveled important insight into many hematologic disorders including anemia of CKD. This knowledge has also unlocked unique opportunities to modulate hepcidin via agonists and antagonists of hepcidin and its feedback pathways to treat clinical conditions. Many such agents are being developed and have potential therapeutic utility in future.
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Anemia/etiología , Hepcidinas/metabolismo , Insuficiencia Renal Crónica/complicaciones , Anemia/diagnóstico , Anemia/tratamiento farmacológico , Anemia/metabolismo , Biomarcadores/metabolismo , Eritropoyesis/fisiología , Hematínicos/uso terapéutico , Hepcidinas/agonistas , Hepcidinas/antagonistas & inhibidores , Humanos , Hierro/metabolismoRESUMEN
BACKGROUND AND AIMS: The role of hepcidin in inflammatory bowel disease [IBD] in children with anaemia is poorly understood. However, it has been shown that vitamin D suppresses hepcidin expression. We aimed to assess serum hepcidin levels and the effect of vitamin D treatment on those levels in newly diagnosed IBD paediatric patients. METHODS: Eighty-five children were prospectively recruited in the Dana-Dwek Children's Hospital [40 newly diagnosed IBD, 45 healthy controls, 47% female, mean age 13.5 ± 3.4 years]. Blood samples for measurement of interleukin 6 [IL-6], C-reactive protein [CRP], hepcidin, iron parameters and 25-hydroxyvitamin D [25-(OH)-D] levels were obtained at baseline. Patients with mild-to-moderate signs and symptoms of IBD were treated with 4000 units of vitamin D daily for 2 weeks, after which the blood tests were repeated. RESULTS: Basal hepcidin, IL-6, CRP and platelet counts were significantly higher, and haemoglobin, serum iron and transferrin levels were significantly lower in the IBD children compared to controls [p < 0.001]. Eighteen patients completed 2 weeks of treatment with vitamin D. Following treatment, serum 25-(OH)-D concentrations increased by 40% [from 22.5 to 32.5 ng/mL], and serum hepcidin, CRP and ferritin levels decreased by 81%, 81% and 40% [from 33.9 to 6.7 ng/mL, from 23.9 to 4.7 mg/L, and from 27 to 16 ng/mL, respectively] [p ≤ 0.001]. CONCLUSION: Serum hepcidin levels were significantly higher in IBD paediatric patients compared to controls. Following vitamin D treatment, serum hepcidin concentration decreased significantly. These findings suggest a potential role for vitamin D in treating anaemia in IBD children. CLINICALTRIALS.GOV NUMBER: NCT03145896.
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Hepcidinas/sangre , Enfermedades Inflamatorias del Intestino/sangre , Vitamina D/uso terapéutico , Adolescente , Anemia/sangre , Anemia/tratamiento farmacológico , Anemia/etiología , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Niño , Femenino , Ferritinas/sangre , Hepcidinas/antagonistas & inhibidores , Humanos , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Interleucina-6/sangre , Masculino , Recuento de Plaquetas , Estudios Prospectivos , Vitamina D/efectos adversos , Vitamina D/sangreRESUMEN
In chronic kidney disease both renal insufficiency and chronic inflammation trigger elevated hepcidin levels, which impairs iron uptake, availability. and erythropoiesis. Here we report the two first-in-human phase 1 trials of PRS-080#22, a novel, rationally engineered Anticalin protein that targets and antagonizes hepcidin. A single intravenous infusion of placebo or PRS-080#22 was administered to 48 healthy volunteers (phase 1a) and 24 patients with end stage chronic kidney disease (CKD) on hemodialysis (phase 1b) at different doses (0.08-16mg/kg for the phase 1a study and 2-8mg/kg for the phase 1b study) in successive dosing cohorts. The primary endpoint for both randomized, double-blind, phase 1 trials was safety and tolerability. Following treatment, all subjects were evaluable, with none experiencing dose limiting toxicities. Most adverse events were mild. One serious adverse event occurred in the phase 1b (CKD patient) study. There were no clinically significant changes in safety laboratory values or vital signs. PRS-080#22 showed dose-proportional pharmacokinetics (PK), with a terminal half-life of approximately three days in healthy volunteers and 10 to 12 days in CKD patients. Serum hepcidin levels were suppressed in a dose dependent manner and remained low for up to 48 hours after dosing. PRS-080#22 dose-dependently mobilized serum iron with increases in both serum iron concentration and transferrin saturation. No consistent changes were observed with regard to ferritin, reticulocytes, hemoglobin, and reticulocyte hemoglobin. Low titer anti-drug-antibodies were detected in five healthy volunteers but in none of the CKD patients. PRS-080#22, a novel Anticalin protein with picomolar affinity for hepcidin, was safe and well-tolerated when administered to healthy volunteers and CKD patients at all doses tested. The drug exhibited linear pharmacokinetics, longer half-life in CKD patients in comparison to healthy volunteers as well as expected pharmacodynamic effects which hold promise for further clinical studies.
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Hepcidinas/antagonistas & inhibidores , Lipocalinas/farmacología , Insuficiencia Renal Crónica/tratamiento farmacológico , Adulto , Método Doble Ciego , Femenino , Semivida , Voluntarios Sanos , Humanos , Infusiones Intravenosas , Lipocalinas/farmacocinética , Masculino , Persona de Mediana Edad , Diálisis Renal/métodosAsunto(s)
Citocinas/metabolismo , Células Precursoras Eritroides/efectos de los fármacos , Células Precursoras Eritroides/metabolismo , Eritropoyetina/farmacología , Hepcidinas/antagonistas & inhibidores , Hepcidinas/sangre , Hierro/sangre , Proteínas Musculares/metabolismo , Animales , Eritropoyetina/uso terapéutico , Ratones , Ratones NoqueadosRESUMEN
Hepcidin has emerged as the central regulatory molecule in systemic iron homeostasis. The inhibition of hepcidin may be a favorable strategy for the treatment of anemia of chronic disease. Here, we have reported the design, synthesis, and structure-activity relationships (SAR) of a series of 4-aminopyrimidine compounds as inhibitors of hepcidin production. The optimization study of 1 led to the design of a potent and bioavailable inhibitor of hepcidin production, 34 (DS42450411), which showed serum hepcidin-lowering effects in a mouse model of interleukin-6-induced acute inflammation.
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Aminopiridinas/farmacología , Anemia/tratamiento farmacológico , Hepcidinas/antagonistas & inhibidores , Quinazolinas/farmacología , Administración Oral , Aminopiridinas/administración & dosificación , Aminopiridinas/síntesis química , Aminopiridinas/farmacocinética , Anemia/etiología , Animales , Sitios de Unión , Línea Celular Tumoral , Diseño de Fármacos , Hepcidinas/sangre , Hepcidinas/química , Humanos , Inflamación/inducido químicamente , Inflamación/complicaciones , Interleucina-6/metabolismo , Hierro/metabolismo , Masculino , Ratones Endogámicos C57BL , Estructura Molecular , Quinazolinas/administración & dosificación , Quinazolinas/síntesis química , Quinazolinas/farmacocinética , Relación Estructura-ActividadRESUMEN
Hepcidin is a peptide hormone and has emerged as the central molecule regulating systemic iron homeostasis. Hepcidin inhibition could be a strategy for treating anemia of chronic disease. We previously reported the discovery of DS79182026, a new inhibitor of hepcidin production, from phenotypic screening using the human hepatocyte HepG2 cell line. In this study, we utilized a combination of affinity purification-based chemical proteomics and radioactive compound binding assay, and identified several candidate proteins. Purified recombinant proteins were subjected to radioactive compound binding assays for validation, and ALK2 and ALK3 demonstrated specific binding to the compound. Since ALK2 is known to be related to hepcidin production, we focused on ALK2 and found that its knockdown decreased hepcidin expression; we also found a strong correlation (Râ¯=â¯0.920) between pharmacological activity and compound affinity to ALK2. These results indicate that ALK2 is the primary target protein of our new hepcidin production inhibitors.
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Hepcidinas/antagonistas & inhibidores , Proteómica/métodos , Ensayo de Unión Radioligante/métodos , Receptores de Activinas Tipo I/metabolismo , Anemia/tratamiento farmacológico , Células Hep G2 , Humanos , Unión Proteica , Proteínas/aislamiento & purificaciónRESUMEN
PURPOSE OF REVIEW: Iron deficiency is a major contributory cause to the development of anaemia in chronic kidney disease (CKD), and thus, iron replacement therapy plays a critical role in the management of this condition. The two main routes for administering iron are oral and intravenous, and there have been a number of new publications relevant to both routes of administration. RECENT FINDINGS: Recent developments on the topic of iron management in CKD include the introduction of new oral iron preparations, as well as two recent meta-analyses on iron therapy in CKD (one on oral versus intravenous iron, and one on high- versus low-dose intravenous iron in haemodialysis patients). There is also increasing interest in other strategies to improve iron availability, such as intradialytic iron, hypoxia-inducible factor stabilization and antihepcidin strategies. SUMMARY: Even despite the latest publications in this field, we are still left with serious gaps in our evidence base on how best to provide supplemental iron to CKD patients. Most of the evidence suggests that intravenous iron is superior to oral iron in increasing haemoglobin and minimizing the use of erythropoiesis-stimulating agents, but the safety of intravenous iron remains a controversy. The PIVOTAL study will hopefully provide informative data to fill some of the gap in the evidence-base and inform best clinical practice.
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Anemia Ferropénica/tratamiento farmacológico , Compuestos de Hierro/administración & dosificación , Insuficiencia Renal Crónica/complicaciones , Administración Intravenosa , Administración Oral , Anemia Ferropénica/etiología , Hematínicos/farmacología , Hematínicos/uso terapéutico , Hepcidinas/antagonistas & inhibidores , Humanos , Inhibidores de Prolil-Hidroxilasa/farmacología , Inhibidores de Prolil-Hidroxilasa/uso terapéutico , Diálisis Renal , Insuficiencia Renal Crónica/terapiaRESUMEN
Hepcidin is a crucial peptide for regulating cellular iron efflux. Because iron is essential for cell survival, especially for highly active cells, such as tumor cells, it is imperative to understand how tumor cells manipulate hepcidin expression for their own metabolic needs. Studies suggest that hepcidin expression and regulation in tumor cells show important differences in comparison with those in non-tumorous cells. These differences should be investigated to develop new strategies to fight cancer cells. Manipulating hepcidin expression to starve cancer cells for iron may prove to be a new therapy in the anticancer arsenal.
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Susceptibilidad a Enfermedades , Regulación de la Expresión Génica , Hepcidinas/genética , Neoplasias/genética , Animales , Biomarcadores , Descubrimiento de Drogas , Hepcidinas/antagonistas & inhibidores , Hepcidinas/metabolismo , Humanos , Inflamación/genética , Inflamación/metabolismo , Hierro/metabolismo , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Unión Proteica , Isoformas de Proteínas , Transporte de Proteínas , Transducción de SeñalRESUMEN
BACKGROUND AND PURPOSE: Anaemia of chronic disease (ACD) has been linked to iron-restricted erythropoiesis imposed by high circulating levels of hepcidin, a 25 amino acid hepatocyte-derived peptide that controls systemic iron homeostasis. Here, we report the engineering of the human lipocalin-derived, small protein-based anticalin PRS-080 hepcidin antagonist with high affinity and selectivity. EXPERIMENTAL APPROACH: Anticalin- and hepcidin-specific pharmacokinetic (PK)/pharmacodynamic modelling (PD) was used to design and select the suitable drug candidate based on t1/2 extension and duration of hepcidin suppression. The development of a novel free hepcidin assay enabled accurate analysis of bioactive hepcidin suppression and elucidation of the observed plasma iron levels after PRS-080-PEG30 administration in vivo. KEY RESULTS: PRS-080 had a hepcidin-binding affinity of 0.07 nM and, after coupling to 30 kD PEG (PRS-080-PEG30), a t1/2 of 43 h in cynomolgus monkeys. Dose-dependent iron mobilization and hepcidin suppression were observed after a single i.v. dose of PRS-080-PEG30 in cynomolgus monkeys. Importantly, in these animals, suppression of free hepcidin and subsequent plasma iron elevation were sustained during repeated s.c. dosing. After repeated dosing and followed by a treatment-free interval, all iron parameters returned to pre-dose values. CONCLUSIONS AND IMPLICATIONS: In conclusion, we developed a dose-dependent and safe approach for the direct suppression of hepcidin, resulting in prolonged iron mobilization to alleviate iron-restricted erythropoiesis that can address the root cause of ACD. PRS-080-PEG30 is currently in early clinical development.
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Hepcidinas/antagonistas & inhibidores , Hepcidinas/sangre , Hierro/sangre , Animales , Femenino , Macaca fascicularis , Masculino , Modelos BiológicosRESUMEN
To understand the potential mechanisms involved in the beneficial effects of aspirin (ASA) in mood disorders, Alzheimer's (AD) and Parkinson's disease (PD), we investigated the effects of ASA on the expression of iron transport proteins transferrin receptor 1 (TfR1), ferroportin 1 (Fpn1), and iron storage protein ferritin light chain (Ft-L) in interleukin-6 (IL-6)-treated PC-12 cells. We demonstrated that IL-6 alone could induce a severe decline in Fpn1 expression and cell viability, and an increase in Ft-L protein, while ASA could markedly diminish the effects of IL-6 on these parameters. We also found that IL-6 significantly increased hepcidin expression and janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) phosphorylation, while ASA also observably suppressed these IL-6-induced effects. The data imply that ASA increases Fpn1 expression by inhibiting hepcidin expression via the IL-6/JAK/STAT3 pathway and show that the reduced content of Ft-L is due to the increased Fpn1 and subsequent iron release in the cells. The reduction of iron in neuronal cells by the increased expression of Fpn1 might be partly associated with the beneficial effects of ASA on mood disorders, AD and PD.