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Wudhikulprapan W, Chattipakorn SC, Chattipakorn N, Kumfu S. Iron overload and programmed bone marrow cell death: Potential mechanistic insights. Arch Biochem Biophys 2024; 754:109954. [PMID: 38432564 DOI: 10.1016/j.abb.2024.109954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/29/2024] [Accepted: 02/29/2024] [Indexed: 03/05/2024]
Abstract
Iron overload has detrimental effects on bone marrow mesenchymal stem cells (BMMSCs), cells crucial for bone marrow homeostasis and hematopoiesis support. Excessive iron accumulation leads to the production of reactive oxygen species (ROS), resulting in cell death, cell cycle arrest, and disruption of vital cellular pathways. Although apoptosis has been extensively studied, other programmed cell death mechanisms including autophagy, necroptosis, and ferroptosis also play significant roles in iron overload-induced bone marrow cell death. Studies have highlighted the involvement of ROS production, DNA damage, MAPK pathways, and mitochondrial dysfunction in apoptosis. In addition, autophagy and ferroptosis are activated, as shown by the degradation of cellular components and lipid peroxidation, respectively. However, several compounds and antioxidants show promise in mitigating iron overload-induced cell death by modulating ROS levels, MAPK pathways, and mitochondrial integrity. Despite early indications, more comprehensive research and clinical studies are needed to better understand the interplay between these programmed cell death mechanisms and enable development of effective therapeutic strategies. This review article emphasizes the importance of studying multiple cell death pathways simultaneously and investigating potential rescuers to combat iron overload-induced bone marrow cell death.
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Affiliation(s)
- Wanat Wudhikulprapan
- Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Siriporn C Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand; Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Nipon Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand; Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Sirinart Kumfu
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand; Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
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Beavers CJ, Ambrosy AP, Butler J, Davidson BT, Gale SE, Piña IL, Mastoris I, Reza N, Mentz RJ, Lewis GD. Iron Deficiency in Heart Failure: A Scientific Statement from the Heart Failure Society of America. J Card Fail 2023; 29:1059-1077. [PMID: 37137386 DOI: 10.1016/j.cardfail.2023.03.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/10/2023] [Accepted: 03/23/2023] [Indexed: 05/05/2023]
Abstract
Iron deficiency is present in approximately 50% of patients with symptomatic heart failure and is independently associated with worse functional capacity, lower quality of, life and increased mortality. The purpose of this document is to summarize current knowledge of how iron deficiency is defined in heart failure and its epidemiology and pathophysiology, as well as pharmacological considerations for repletion strategies. This document also summarizes the rapidly expanding array of clinical trial evidence informing when, how, and in whom to consider iron repletion.
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Affiliation(s)
- Craig J Beavers
- University of Kentucky College of Pharmacy, Lexington, Kentucky.
| | - Andrew P Ambrosy
- Kaiser Permanente Northern California - Division of Research (DOR), Oakland, CA
| | - Javed Butler
- Baylor Scott and White Research Institute, Dallas, Texas; University of Mississippi, Jackson, Mississippi
| | - Beth T Davidson
- Centennial Heart Cardiovascular Consultants, Nashville, Tennessee
| | - Stormi E Gale
- Novant Health Matthews Medical Center, Matthews, North Carolina
| | - Ileana L Piña
- Thomas Jefferson University, Philadelphia, Pennsylvania
| | | | - Nosheen Reza
- Division of Cardiovascular Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Robert J Mentz
- Duke University School of Medicine, Durham, North Carolina
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Yin X, Zhou M, Zhang L, Fu Y, Xu M, Wang X, Cui Z, Gao Z, Li M, Dong Y, Feng H, Ma S, Chen C. Histone chaperone ASF1A accelerates chronic myeloid leukemia blast crisis by activating Notch signaling. Cell Death Dis 2022; 13:842. [PMID: 36184659 PMCID: PMC9527247 DOI: 10.1038/s41419-022-05234-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 08/29/2022] [Accepted: 09/05/2022] [Indexed: 11/30/2022]
Abstract
The blast crisis (BC) is the final deadly phase of chronic myeloid leukemia (CML), which remains a major challenge in clinical management. However, the underlying molecular mechanism driving blastic transformation remains unclear. Here, we show that ASF1A, an essential activator, enhanced the transformation to CML-BC by mediating cell differentiation arrest. ASF1A expression was aberrantly increased in bone marrow samples from CML-BC patients compared with newly diagnosed CML-chronic phase (CP) patients. ASF1A inhibited cell differentiation and promoted CML development in vivo. Mechanistically, we identified ASF1A as a coactivator of the Notch transcriptional complex that induces H3K56ac modification in the promoter regions of Notch target genes, and subsequently enhanced RBPJ binding to these promoter regions, thereby enhancing Notch signaling activation to mediate differentiation arrest in CML cells. Thus, our work suggests that targeting ASF1A might represent a promising therapeutic approach and a biomarker to detect disease progression in CML patients.
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Affiliation(s)
- Xiaolin Yin
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Minran Zhou
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Lu Zhang
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Yue Fu
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China ,grid.27255.370000 0004 1761 1174Department of Physiology & Pathophysiology, School of Basic Medical Science, Cheeloo College of Medicine, Shandong University, Jinan, Shandong China
| | - Man Xu
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Xiaoming Wang
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Zelong Cui
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Zhenxing Gao
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Miao Li
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Yuting Dong
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Huimin Feng
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Sai Ma
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
| | - Chunyan Chen
- grid.27255.370000 0004 1761 1174Department of Hematology, Qilu Hospital, Shandong University, Jinan, Shandong China
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Walters AS, Li Y, Karroum EG, Champion D, Weinstock LB, Bagai K, Afrin LB, Spruyt K. Exploring the role of the endogenous opiate system in the pathogenesis of anemia in an opiate receptor knock-out model of Restless Legs Syndrome. Med Hypotheses 2022; 167:110941. [PMID: 36505961 PMCID: PMC9731170 DOI: 10.1016/j.mehy.2022.110941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Restless Legs Syndrome (RLS) is characterized by bothersome leg discomfort accompanied by an urge to move to obtain relief and symptoms are worse at night and on lying down. There is at least partial and temporary relief with activity. It is also an opioid responsive disorder, often accompanied by iron deficiency with or without anemia, and inflammation may be a precipitating factor in some cases. We created two in-vivo opiate receptor knock out mouse models of RLS - a triple opiate receptor knock-out mouse and a mu opiate receptor knock-out mouse. Both sets of animals were restless during the sleep period as is also true of RLS. Both of our knockout models showed statistically significantly decreased Hemoglobin and Hematocrit indicating anemia and both models showed statistically significant decreases in serum iron suggestive of either iron deficiency anemia or inflammatory anemia. The rest of the hematologic studies were not consistent enough to determine which of these two types of anemia was present in either model. An additional experiment in normal wild type mice showed a statistically significant decrease in serum iron when an opiate receptor blocker was used. To our knowledge this is the first demonstration that deficiency of endogenous opioids might play a role in the production of anemia. Our hypothesis is that an intact endogenous opiate system is necessary for red cell homeostasis. The presence of opioid receptors both on red blood cells and on various immunologically based white blood cells suggest mechanisms by which deficiency in the endogenous opiate system could cause anemia of either the iron deficiency or inflammatory types. The administration of opioid agonists or antagonists to iron deficient cultures of red blood cell precursors is a next step in determining the role of the endogenous opiate system in the maintenance of red cell homeostasis and in the possible prevention of iron deficiency or inflammatory anemia where iron dysregulation is key.
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Affiliation(s)
- Arthur S. Walters
- Sleep Division, Dept of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yuqing Li
- Norman Fixel Institute for Neurological Diseases, Dept of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Elias G. Karroum
- Department of Neurology & Rehabilitation Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC., USA
| | - David Champion
- Sydney Children’s Hospital, Randwick, NSW 2031, Australia
| | - Leonard B. Weinstock
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Kanika Bagai
- Sleep Division, Dept of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lawrence B. Afrin
- Hematology/Oncology, AIM Center for Personalized Medicine, Purchase, New York
| | - Karen Spruyt
- Université de Paris, NeuroDiderot Inserm, France
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Morita T, Nakano D, Kitada K, Morimoto S, Ichihara A, Hitomi H, Kobori H, Shiojima I, Nishiyama A. Chelation of dietary iron prevents iron accumulation and macrophage infiltration in the type I diabetic kidney. Eur J Pharmacol 2015; 756:85-91. [PMID: 25820160 DOI: 10.1016/j.ejphar.2015.03.053] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 03/12/2015] [Accepted: 03/17/2015] [Indexed: 11/24/2022]
Abstract
We previously reported that the functional deletion of p21, a cyclin-dependent kinase inhibitor, in mice attenuated renal cell senescence in streptozotocin (STZ)-induced type 1 diabetic mice. In the present study, we investigated the effect of iron chelation on renal cell senescence and inflammation in the type 1 diabetic kidney. STZ-treated mice showed increase in iron accumulation, tubular cell senescence and macrophage infiltration at week 28 in the kidney. Administering deferasirox, which removes only dietary iron, significantly attenuated iron accumulation in proximal tubules and the number of infiltrating F4/80-positive cells without effecting blood glucose, hematocrit or hemoglobin levels. In contrast however, deferasirox did not influence renal cell senescence. The lack of p21 decreased the renal tubular iron accumulation and did not change tubular cell senescence. Interestingly, the STZ-treated animals showed an increase in p16, another cyclin-dependent kinase inhibitor. The results suggest that type 1 diabetes increases renal tubular iron accumulation and macrophage infiltration through a p21-dependent mechanism, and that the chelation of dietary iron attenuates these responses.
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Affiliation(s)
- Tatsuyori Morita
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan; The Second Department of Internal Medicine, Kansai Medical University, Japan
| | - Daisuke Nakano
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan.
| | - Kento Kitada
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan
| | - Satoshi Morimoto
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan
| | - Atsuhiro Ichihara
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan
| | - Hirofumi Hitomi
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan
| | - Hiroyuki Kobori
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan
| | - Ichiro Shiojima
- Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan
| | - Akira Nishiyama
- Department of Pharmacology, Kagawa University, 1750-1 Miki, Kita, Kagawa, Japan
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Jankowska EA, von Haehling S, Anker SD, Macdougall IC, Ponikowski P. Iron deficiency and heart failure: diagnostic dilemmas and therapeutic perspectives. Eur Heart J 2012; 34:816-29. [PMID: 23100285 PMCID: PMC3596759 DOI: 10.1093/eurheartj/ehs224] [Citation(s) in RCA: 270] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Iron is a micronutrient essential for cellular energy and metabolism, necessary for maintaining body homoeostasis. Iron deficiency is an important co-morbidity in patients with heart failure (HF). A major factor in the pathogenesis of anaemia, it is also a separate condition with serious clinical consequences (e.g. impaired exercise capacity) and poor prognosis in HF patients. Experimental evidence suggests that iron therapy in iron-deficient animals may activate molecular pathways that can be cardio-protective. Clinical studies have demonstrated favourable effects of i.v. iron on the functional status, quality of life, and exercise capacity in HF patients. It is hypothesized that i.v. iron supplementation may become a novel therapy in HF patients with iron deficiency.
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Affiliation(s)
- Ewa A Jankowska
- Department of Heart Diseases, Wroclaw Medical University, ul Weigla 5, 50-981 Wroclaw, Poland.
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Yin L, Unger EL, Jellen LC, Earley CJ, Allen RP, Tomaszewicz A, Fleet JC, Jones BC. Systems genetic analysis of multivariate response to iron deficiency in mice. Am J Physiol Regul Integr Comp Physiol 2012; 302:R1282-96. [PMID: 22461179 DOI: 10.1152/ajpregu.00634.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of this study was to identify genes that influence iron regulation under varying dietary iron availability. Male and female mice from 20+ BXD recombinant inbred strains were fed iron-poor or iron-adequate diets from weaning until 4 mo of age. At death, the spleen, liver, and blood were harvested for the measurement of hemoglobin, hematocrit, total iron binding capacity, transferrin saturation, and liver, spleen and plasma iron concentration. For each measure and diet, we found large, strain-related variability. A principal-components analysis (PCA) was performed on the strain means for the seven parameters under each dietary condition for each sex, followed by quantitative trait loci (QTL) analysis on the factors. Compared with the iron-adequate diet, iron deficiency altered the factor structure of the principal components. QTL analysis, combined with PosMed (a candidate gene searching system) published gene expression data and literature citations, identified seven candidate genes, Ptprd, Mdm1, Picalm, lip1, Tcerg1, Skp2, and Frzb based on PCA factor, diet, and sex. Expression of each of these is cis-regulated, significantly correlated with the corresponding PCA factor, and previously reported to regulate iron, directly or indirectly. We propose that polymorphisms in multiple genes underlie individual differences in iron regulation, especially in response to dietary iron challenge. This research shows that iron management is a highly complex trait, influenced by multiple genes. Systems genetics analysis of iron homeostasis holds promise for developing new methods for prevention and treatment of iron deficiency anemia and related diseases.
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Affiliation(s)
- Lina Yin
- Graduate Program in Neuroscience,The Pennsylvania State University, PA 16802, USA
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Messer JG, Cooney PT, Kipp DE. Iron chelator deferoxamine alters iron-regulatory genes and proteins and suppresses osteoblast phenotype in fetal rat calvaria cells. Bone 2010; 46:1408-15. [PMID: 20102755 DOI: 10.1016/j.bone.2010.01.376] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 01/17/2010] [Accepted: 01/19/2010] [Indexed: 12/31/2022]
Abstract
There are few studies describing the extent to which low iron status affects osteoblastogenesis, despite evidence that iron deficiency produces adverse effects on bone density. The purpose of this study was to evaluate alterations in intracellular iron status by measuring iron-regulated gene and protein expression and to describe development of osteoblast phenotype in primary cells treated with iron chelator deferoxamine (DFOM) during differentiation. Using the well-described fetal rat calvaria model, cells were incubated with 0-8 microM DFOM throughout differentiation (confluence to day (D) 21), or only during early differentiation (confluence to D13-15) or late differentiation (D13-15 to D21). Changes in intracellular iron status were determined by measuring alterations in gene and protein expression of transferrin receptor and ferritin light chain and heavy chain. Development of osteoblast phenotype was monitored by measuring expression of genes that are known to be up-regulated during differentiation, analyzing the percentage of mineralized surface area, and counting the number of multi-layered bone nodules at the end of culture. Results indicate that treatment throughout differentiation with 8 microM DFOM alters iron-regulated genes and proteins by mid-differentiation (D13-15) in a pattern consistent with iron deficiency with concomitant down-regulation of osteoblast phenotype genes, especially osteocalcin. Additionally, alkaline phosphatase staining was lower and there was about 70% less mineralized surface area (p<0.05) by D21 in wells treated throughout differentiation with 8 microM DFOM compared to control. Down-regulation of osteocalcin and alkaline phosphatase mRNA (p<0.05) and suppressed mineralization (p<0.05) was also evident at D21 in cells treated only during early differentiation. In contrast, treatment during late differentiation did not alter osteoblastic outcomes by D21. In conclusion, it appears that iron is required for normal osteoblast phenotype development, and that early rather than late differentiation events may be more sensitive to iron availability.
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Affiliation(s)
- Jonathan G Messer
- Department of Nutrition, University of North Carolina at Greensboro, Greensboro, NC 27412, USA
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A retroviral mutagenesis screen reveals strong cooperation between Bcl11a overexpression and loss of the Nf1 tumor suppressor gene. Blood 2008; 113:1075-85. [PMID: 18948576 DOI: 10.1182/blood-2008-03-144436] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
NF1 inactivation occurs in specific human cancers, including juvenile myelomonocytic leukemia, an aggressive myeloproliferative disorder of childhood. However, evidence suggests that Nf1 loss alone does not cause leukemia. We therefore hypothesized that inactivation of the Nf1 tumor suppressor gene requires cooperating mutations to cause acute leukemia. To search for candidate genes that cooperate with Nf1 deficiency in leukemogenesis, we performed a forward genetic screen using retroviral insertion mutagenesis in Nf1 mutant mice. We identified 43 common proviral insertion sites that contain candidate genes involved in leukemogenesis. One of these genes, Bcl11a, confers a growth advantage in cultured Nf1 mutant hematopoietic cells and causes early onset of leukemia of either myeloid or lymphoid lineage in mice when expressed in Nf1-deficient bone marrow. Bcl11a-expressing cells display compromised p21(Cip1) induction, suggesting that Bcl11a's oncogenic effects are mediated, in part, through suppression of p21(Cip1). Importantly, Bcl11a is expressed in human chronic myelomonocytic leukemia and juvenile myelomonocytic leukemia samples. A subset of AML patients, who had poor outcomes, of 16 clusters, displayed high levels of BCL11A in leukemic cells. These findings suggest that deregulated Bcl11a cooperates with Nf1 in leukemogenesis, and a therapeutic strategy targeting the BCL11A pathway may prove beneficial in the treatment of leukemia.
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Valis K, Neubauerova J, Man P, Pompach P, Vohradsky J, Kovar J. VDAC2 and aldolase A identified as membrane proteins of K562 cells with increased expression under iron deprivation. Mol Cell Biochem 2008; 311:225-31. [DOI: 10.1007/s11010-008-9712-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Accepted: 01/29/2008] [Indexed: 10/22/2022]
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Redistribution of accumulated cell iron: a modality of chelation with therapeutic implications. Blood 2008; 111:1690-9. [DOI: 10.1182/blood-2007-07-102335] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
AbstractVarious pathologies are characterized by the accumulation of toxic iron in cell compartments. In anemia of chronic disease, iron is withheld by macrophages, leaving extracellular fluids iron-depleted. In Friedreich ataxia, iron levels rise in the mitochondria of excitable cells but decrease in the cytosol. We explored the possibility of using deferiprone, a membrane-permeant iron chelator in clinical use, to capture labile iron accumulated in specific organelles of cardiomyocytes and macrophages and convey it to other locations for physiologic reuse. Deferiprone's capacity for shuttling iron between cellular organelles was assessed with organelle-targeted fluorescent iron sensors in conjunction with time-lapse fluorescence microscopy imaging. Deferiprone facilitated transfer of iron from extracellular media into nuclei and mitochondria, from nuclei to mitochondria, from endosomes to nuclei, and from intracellular compartments to extracellular apotransferrin. Furthermore, it mobilized iron from iron-loaded cells and donated it to preerythroid cells for hemoglobin synthesis, both in the presence and in the absence of transferrin. These unique properties of deferiprone underlie mechanistically its capacity to alleviate iron accumulation in dentate nuclei of Friedreich ataxia patients and to donate tissue-chelated iron to plasma transferrin in thalassemia intermedia patients. Deferiprone's shuttling properties could be exploited clinically for treating diseases involving regional iron accumulation.
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