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Sumi MP, Tupta B, Roychowdhury S, Comhair S, Asosingh K, Stuehr DJ, Erzurum SC, Ghosh A. Hemoglobin resident in the lung epithelium is protective for smooth muscle soluble guanylate cyclase function. Redox Biol 2023; 63:102717. [PMID: 37120930 PMCID: PMC10172757 DOI: 10.1016/j.redox.2023.102717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/17/2023] [Accepted: 04/24/2023] [Indexed: 05/02/2023] Open
Abstract
Hemoglobin (Hb) present in the lung epithelium is of unknown significance. However Hb being an nitric oxide (NO) scavenger can bind to NO and reduce its deleterious effects. Hence we postulated an NO scavenging role for this lung Hb. Doing transwell co-culture with bronchial epithelial cells, A549/16-HBE (apical) and human airway smooth muscle cells (HASMCs as basal), we found that Hb can protect the smooth muscle soluble guanylyl cyclase (sGC) from excess NO. Inducing the apical A549/16-HBE cells with cytokines to trigger iNOS expression and NO generation caused a time dependent increase in SNO-sGC and this was accompanied with a concomitant drop in sGC-α1β1 heterodimerization. Silencing Hbαβ in the apical cells further increased the SNO on sGC with a faster drop in the sGC heterodimer and these effects were additive along with further silencing of thioredoxin 1 (Trx1). Since heme of Hb is critical for NO scavenging we determined the Hb heme in a mouse model of allergic asthma (OVA) and found that Hb in the inflammed OVA lungs was low in heme or heme-free relative to those of naïve lungs. Further we established a direct correlation between the status of the sGC heterodimer and the Hb heme from lung samples of human asthma, iPAH, COPD and cystic fibrosis. These findings present a new mechanism of protection of lung sGC by the epithelial Hb, and suggests that this protection maybe lost in asthma or COPD where lung Hb is unable to scavenge the NO due to it being heme-deprived.
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Affiliation(s)
- Mamta P Sumi
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Blair Tupta
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Sanjoy Roychowdhury
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Suzy Comhair
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Kewal Asosingh
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Dennis J Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Serpil C Erzurum
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Arnab Ghosh
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA.
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2
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Keller TCS, Lechauve C, Keller AS, Broseghini-Filho GB, Butcher JT, Askew Page HR, Islam A, Tan ZY, DeLalio LJ, Brooks S, Sharma P, Hong K, Xu W, Padilha AS, Ruddiman CA, Best AK, Macal E, Kim-Shapiro DB, Christ G, Yan Z, Cortese-Krott MM, Ricart K, Patel R, Bender TP, Sonkusare SK, Weiss MJ, Ackerman H, Columbus L, Isakson BE. Endothelial alpha globin is a nitrite reductase. Nat Commun 2022; 13:6405. [PMID: 36302779 PMCID: PMC9613979 DOI: 10.1038/s41467-022-34154-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 10/04/2022] [Indexed: 01/29/2023] Open
Abstract
Resistance artery vasodilation in response to hypoxia is essential for matching tissue oxygen and demand. In hypoxia, erythrocytic hemoglobin tetramers produce nitric oxide through nitrite reduction. We hypothesized that the alpha subunit of hemoglobin expressed in endothelium also facilitates nitrite reduction proximal to smooth muscle. Here, we create two mouse strains to test this: an endothelial-specific alpha globin knockout (EC Hba1Δ/Δ) and another with an alpha globin allele mutated to prevent alpha globin's inhibitory interaction with endothelial nitric oxide synthase (Hba1WT/Δ36-39). The EC Hba1Δ/Δ mice had significantly decreased exercise capacity and intracellular nitrite consumption in hypoxic conditions, an effect absent in Hba1WT/Δ36-39 mice. Hypoxia-induced vasodilation is significantly decreased in arteries from EC Hba1Δ/Δ, but not Hba1WT/Δ36-39 mice. Hypoxia also does not lower blood pressure in EC Hba1Δ/Δ mice. We conclude the presence of alpha globin in resistance artery endothelium acts as a nitrite reductase providing local nitric oxide in response to hypoxia.
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Affiliation(s)
- T C Stevenson Keller
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Christophe Lechauve
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Alexander S Keller
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Gilson Brás Broseghini-Filho
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitória, Brazil
| | - Joshua T Butcher
- Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, USA
| | - Henry R Askew Page
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Aditi Islam
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Zhe Yin Tan
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Leon J DeLalio
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Steven Brooks
- Physiology Unit, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Poonam Sharma
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Kwangseok Hong
- Department of Physical Education, College of Education, Chung-Ang University, Seoul, South Korea
| | - Wenhao Xu
- Transgenic Mouse Facility, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA
| | | | - Claire A Ruddiman
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Angela K Best
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Edgar Macal
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Daniel B Kim-Shapiro
- Department of Physics, Translational Science Center, Wake Forest University, Winston-Salem, NC, USA
| | - George Christ
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Zhen Yan
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Miriam M Cortese-Krott
- Cardiovascular Research Laboratory, Division of Cardiology, Pneumology and Angiology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Karina Ricart
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rakesh Patel
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Timothy P Bender
- Department of Microbiology, Immunology and Cancer, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Swapnil K Sonkusare
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Mitchell J Weiss
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Hans Ackerman
- Physiology Unit, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Linda Columbus
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Brant E Isakson
- Robert M Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, USA.
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3
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Krüppel-Like Factor 1: A Pivotal Gene Regulator in Erythropoiesis. Cells 2022; 11:cells11193069. [PMID: 36231031 PMCID: PMC9561966 DOI: 10.3390/cells11193069] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/21/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Krüppel-like factor 1 (KLF1) plays a crucial role in erythropoiesis. In-depth studies conducted on mice and humans have highlighted its importance in erythroid lineage commitment, terminal erythropoiesis progression and the switching of globin genes from γ to β. The role of KLF1 in haemoglobin switching is exerted by the direct activation of β-globin gene and by the silencing of γ-globin through activation of BCL11A, an important γ-globin gene repressor. The link between KLF1 and γ-globin silencing identifies this transcription factor as a possible therapeutic target for β-hemoglobinopathies. Moreover, several mutations have been identified in the human genes that are responsible for various benign phenotypes and erythroid disorders. The study of the phenotype associated with each mutation has greatly contributed to the current understanding of the complex role of KLF1 in erythropoiesis. This review will focus on some of the principal functions of KLF1 on erythroid cell commitment and differentiation, spanning from primitive to definitive erythropoiesis. The fundamental role of KLF1 in haemoglobin switching will be also highlighted. Finally, an overview of the principal human mutations and relative phenotypes and disorders will be described.
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4
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Han G, Cao C, Yang X, Zhao GW, Hu XJ, Yu DL, Yang RF, Yang K, Zhang YY, Wang WT, Liu XZ, Xu P, Liu XH, Chen P, Xue Z, Liu DP, Lv X. Nrf2 expands the intracellular pool of the chaperone AHSP in a cellular model of β-thalassemia. Redox Biol 2022; 50:102239. [PMID: 35092867 PMCID: PMC8801382 DOI: 10.1016/j.redox.2022.102239] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/21/2021] [Accepted: 01/14/2022] [Indexed: 12/30/2022] Open
Abstract
In β-thalassemia, free α-globin chains are unstable and tend to aggregate or degrade, releasing toxic heme, porphyrins and iron, which produce reactive oxygen species (ROS). α-Hemoglobin-stabilizing protein (AHSP) is a potential modifier of β-thalassemia due to its ability to escort free α-globin and inhibit the cellular production of ROS. The influence of AHSP on the redox equilibrium raises the question of whether AHSP expression is regulated by components of ROS signaling pathways and/or canonical redox proteins. Here, we report that AHSP expression in K562 cells could be stimulated by NFE2-related factor 2 (Nrf2) and its agonist tert-butylhydroquinone (tBHQ). This tBHQ-induced increase in AHSP expression was also observed in Ter119+ mouse erythroblasts at each individual stage during terminal erythroid differentiation. We further report that the AHSP level was elevated in α-globin-overexpressing K562 cells and staged erythroblasts from βIVS-2-654 thalassemic mice. tBHQ treatment partially alleviated, whereas Nrf2 or AHSP knockdown exacerbated, α-globin precipitation and ROS production in fetal liver-derived thalassemic erythroid cells. MafG and Nrf2 occupancy at the MARE-1 site downstream of the AHSP transcription start site was detected in K562 cells. Finally, we show that MafG facilitated the activation of the AHSP gene in K562 cells by Nrf2. Our results demonstrate Nrf2-mediated feedback regulation of AHSP in response to excess α-globin, as occurs in β-thalassemia.
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5
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Tupta B, Stuehr E, Sumi MP, Sweeny EA, Smith B, Stuehr DJ, Ghosh A. GAPDH is involved in the heme-maturation of myoglobin and hemoglobin. FASEB J 2022; 36:e22099. [PMID: 34972240 DOI: 10.1096/fj.202101237rr] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 10/27/2021] [Accepted: 11/29/2021] [Indexed: 12/26/2022]
Abstract
GAPDH, a heme chaperone, has been previously implicated in the incorporation of heme into iNOS and soluble guanylyl cyclase (sGC). Since sGC is critical for myoglobin (Mb) heme-maturation, we investigated the role of GAPDH in the maturation of this globin, as well as hemoglobins α, β, and γ. Utilizing cell culture systems, we found that overexpression of wild-type GAPDH increased, whereas GAPDH mutants H53A and K227A decreased, the heme content of Mb and Hbα and Hbβ. Overexpression of wild-type GAPDH fully recovered the heme-maturation inhibition observed with the GAPDH mutants. Partial rescue was observed by overexpression of sGCβ1 but not by overexpression of a sGCΔβ1 deletion mutant, which is unable to bind the sGCα1 subunit required to form the active sGCα1β1 complex. Wild type and mutant GAPDH was found to be associated in a complex with each of the globins and Hsp90. GAPDH at endogenous levels was found to be associated with Mb in differentiating C2C12 myoblasts, and with Hbγ or Hbα in differentiating HiDEP-1 erythroid progenitor cells. Knockdown of GAPDH in C2C12 cells suppressed Mb heme-maturation. GAPDH knockdown in K562 erythroleukemia cells suppressed Hbα and Hbγ heme-maturation as well as Hb dimerization. Globin heme incorporation was not only dependent on elevated sGCα1β1 heterodimer formation, but also influenced by iron provision and magnitude of expression of GAPDH, d-aminolevulinic acid, and FLVCR1b. Together, our data support an important role for GAPDH in the maturation of myoglobin and γ, β, and α hemoglobins.
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Affiliation(s)
- Blair Tupta
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Eric Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Mamta P Sumi
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Elizabeth A Sweeny
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Brandon Smith
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Dennis J Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
| | - Arnab Ghosh
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, Ohio, USA
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6
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Roffel MP, Boudewijn IM, van Nijnatten JLL, Faiz A, Vermeulen CJ, van Oosterhout AJ, Affleck K, Timens W, Bracke KR, Maes T, Heijink IH, Brandsma CA, van den Berge M. Identification of asthma associated microRNAs in bronchial biopsies. Eur Respir J 2021; 59:13993003.01294-2021. [PMID: 34446467 DOI: 10.1183/13993003.01294-2021] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/30/2021] [Indexed: 11/05/2022]
Abstract
Changes in microRNA (miRNA) expression can contribute to the pathogenesis of many diseases, including asthma. We aimed to identify miRNAs that are differentially expressed between asthma patients and healthy controls and explored their association with clinical and inflammatory parameters of asthma.Differentially expressed miRNAs were determined by small RNA sequencing on bronchial biopsies of 79 asthma patients and 82 healthy controls using linear regression models. Differentially expressed miRNAs were associated with clinical and inflammatory asthma features. Potential miRNA-mRNA interactions were analysed using mRNA data available from the same bronchial biopsies and enrichment of pathways was identified with Enrichr and g:Profiler.In total 78 differentially expressed miRNAs were identified in bronchial biopsies of asthma patients compared to controls, of which 60 remained differentially expressed after controlling for smoke and inhaled corticosteroid treatment. We identified several asthma associated miRNAs, including miR-125b-5p and miR-223-3p, based on a significant association with multiple clinical and inflammatory asthma features and their negative correlation with genes associated with the presence of asthma. The most enriched biological pathway(s) affected by miR-125b-5p and miR-223-3p were inflammatory response and cilium assembly and organisation. Of interest, we identified that lower expression of miR-26a-5p was linked to more severe eosinophilic inflammation as measured in blood, sputum as well as bronchial biopsies. Collectively, we identified miR-125b-5p, miR-223-3p and miR-26a-5p, as potential regulators that could contribute to the pathogenesis of asthma.
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Affiliation(s)
- Mirjam P Roffel
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Department of Respiratory Medicine, Ghent University, University Hospital Ghent, Laboratory for Translational Research in Obstructive Pulmonary Diseases, Ghent, Belgium
| | - Ilse M Boudewijn
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jos L L van Nijnatten
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Faculty of Science, Respiratory Bioinformatics and Molecular Biology (RBMB), University of Technology Sydney, Sydney, Australia
| | - Alen Faiz
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Faculty of Science, Respiratory Bioinformatics and Molecular Biology (RBMB), University of Technology Sydney, Sydney, Australia
| | - Corneel J Vermeulen
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Antoon J van Oosterhout
- Allergic Inflammation Discovery Performance Unit, GlaxoSmithKline, Stevenage, United Kingdom
| | - Karen Affleck
- Adaptive Immunity Research Unit, GlaxoSmithKline, Stevenage, United Kingdom
| | - Wim Timens
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands
| | - Ken R Bracke
- Department of Respiratory Medicine, Ghent University, University Hospital Ghent, Laboratory for Translational Research in Obstructive Pulmonary Diseases, Ghent, Belgium
| | - Tania Maes
- Department of Respiratory Medicine, Ghent University, University Hospital Ghent, Laboratory for Translational Research in Obstructive Pulmonary Diseases, Ghent, Belgium
| | - Irene H Heijink
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Corry-Anke Brandsma
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands.,Both senior authors contributed equally
| | - Maarten van den Berge
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands .,Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Both senior authors contributed equally
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7
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Huang B, Seefelder M, Buck E, Engler T, Lindenberg KS, Klein F, Landwehrmeyer GB, Kochanek S. HAP40 protein levels are huntingtin-dependent and decrease in Huntington disease. Neurobiol Dis 2021; 158:105476. [PMID: 34390835 DOI: 10.1016/j.nbd.2021.105476] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 07/08/2021] [Accepted: 08/09/2021] [Indexed: 12/01/2022] Open
Abstract
The huntingtin-associated protein 40 (HAP40) is an abundant interactor of huntingtin (HTT). In complexes of these proteins, HAP40 tightly binds to HTT in a cleft formed by two larger domains rich in HEAT repeats, and a smaller bridge domain connecting the two. We show that HAP40 steady-state protein levels are directly dependent on HTT (both normal and mutant HTT) and that HAP40 is strongly stabilized by the interaction with HTT resulting in an at least 5-fold increase in HAP40's half-life when bound to HTT. Cellular HAP40 protein levels were reduced in primary fibroblasts and lymphoblasts of Huntington Disease (HD) patients and in brain tissue of a full-length HTT mouse model of HD, concomitant with decreased soluble HTT levels in these cell types. This data and our previous demonstration of coevolution between HTT and HAP40 and evolutionary conservation of their interaction suggest that HAP40 is an obligate interaction partner of HTT. Our observation of reduced HAP40 levels in HD invites further studies, whether HAP40 loss-of-function contributes to the pathophysiology of HD.
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Affiliation(s)
- Bin Huang
- Department of Gene Therapy, Ulm University, 89081 Ulm, Germany
| | | | - Eva Buck
- Department of Neurology, Ulm University, 89081 Ulm, Germany
| | - Tatjana Engler
- Department of Gene Therapy, Ulm University, 89081 Ulm, Germany
| | | | - Fabrice Klein
- Department of Neurology, Ulm University, 89081 Ulm, Germany
| | | | - Stefan Kochanek
- Department of Gene Therapy, Ulm University, 89081 Ulm, Germany.
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8
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Maturation, inactivation, and recovery mechanisms of soluble guanylyl cyclase. J Biol Chem 2021; 296:100336. [PMID: 33508317 PMCID: PMC7949132 DOI: 10.1016/j.jbc.2021.100336] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 11/22/2022] Open
Abstract
Soluble guanylate cyclase (sGC) is a heme-containing heterodimeric enzyme that generates many molecules of cGMP in response to its ligand nitric oxide (NO); sGC thereby acts as an amplifier in NO-driven biological signaling cascades. Because sGC helps regulate the cardiovascular, neuronal, and gastrointestinal systems through its cGMP production, boosting sGC activity and preventing or reversing sGC inactivation are important therapeutic and pharmacologic goals. Work over the last two decades is uncovering the processes by which sGC matures to become functional, how sGC is inactivated, and how sGC is rescued from damage. A diverse group of small molecules and proteins have been implicated in these processes, including NO itself, reactive oxygen species, cellular heme, cell chaperone Hsp90, and various redox enzymes as well as pharmacologic sGC agonists. This review highlights their participation and provides an update on the processes that enable sGC maturation, drive its inactivation, or assist in its recovery in various settings within the cell, in hopes of reaching a better understanding of how sGC function is regulated in health and disease.
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9
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Jalilian B, Zakerhamidi MS, Sahrai M. Linear and nonlinear optical properties of human hemoglobin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 244:118855. [PMID: 32882658 DOI: 10.1016/j.saa.2020.118855] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 08/11/2020] [Accepted: 08/15/2020] [Indexed: 06/11/2023]
Abstract
In this study, we investigated the possibility of interactions between the solvent molecules with the Heme group in the human hemoglobin. The results of this study answer a key question: whether the interactions of the Heme unit with its surroundings are interdependent or independent of the protein units of human hemoglobin. Contributions of the intermolecular interactions were determined by exploiting the solvatochromism spectroscopic data by Kamlet-Taft (KAT) polarity functions. Solvent polarity effects on the nonlinear properties of the Heme's groups in the human hemoglobin (Hb) were investigated via the Z-scan method. The experimental results obtained with spectroscopic and nonlinear optical parameters (absorption coefficient and refractive index) show that the mechanism of solvation and the interactions of Heme are controlled by suitable configuration of the protein units of hemoglobin. In other words, interactions of the Heme with α- and β-globins are an effective factor in controlling the optical behavior of Heme.
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Affiliation(s)
- B Jalilian
- Photonics Group, Aras International Campus, University of Tabriz, Tabriz 51665-163, Iran; Faculty of Physics, University of Tabriz, Tabriz, Iran; Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran
| | - M S Zakerhamidi
- Photonics Group, Aras International Campus, University of Tabriz, Tabriz 51665-163, Iran; Faculty of Physics, University of Tabriz, Tabriz, Iran; Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran.
| | - M Sahrai
- Photonics Group, Aras International Campus, University of Tabriz, Tabriz 51665-163, Iran; Faculty of Physics, University of Tabriz, Tabriz, Iran; Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran
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10
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Bose D, Chakrabarti A. Multiple Functions of Spectrin: Convergent Effects. J Membr Biol 2020; 253:499-508. [PMID: 32990795 DOI: 10.1007/s00232-020-00142-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/19/2020] [Indexed: 10/23/2022]
Abstract
Spectrin is a multifunctional, multi-domain protein most well known in the membrane skeleton of mature human erythrocytes. Here we review the literature on the crosstalk of the chaperone activity of spectrin with its other functionalities. We hypothesize that the chaperone activity is derived from the surface exposed hydrophobic patches present in individual "spectrin-repeat" domains and show a competition between the membrane phospholipid binding functionality and chaperone activity of spectrin. Moreover, we show that post-translational modifications such as glycation which shield these surface exposed hydrophobic patches, reduce the chaperone function. On the other hand, oligomerization which is linked to increase of hydrophobicity is seen to increase it. We note that spectrin seems to prefer haemoglobin as its chaperone client, binding with it preferentially over other denatured proteins. Spectrin is also known to interact with unstable haemoglobin variants with a higher affinity than in the case of normal haemoglobin. We propose that chaperone activity of spectrin could be important in the cellular biochemistry of haemoglobin, particularly in the context of diseases.
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Affiliation(s)
- Dipayan Bose
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, 700064, India.,Homi Bhabha National Institute, Mumbai, 400094, India
| | - Abhijit Chakrabarti
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, 700064, India. .,Homi Bhabha National Institute, Mumbai, 400094, India.
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11
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Abstract
PURPOSE OF REVIEW Erythropoiesis is a complex multistep process going from committed erythroid progenitors to mature red cells. Although recent advances allow the characterization of some components of erythropoiesis, much still remains to be investigated particularly on stress erythropoiesis. This review summarizes recent progresses made to understand the impact of oxidative stress on normal and pathologic erythropoiesis. RECENT FINDINGS During erythroid maturation, reactive oxygen species might function as second messenger through either transient oxidation of cysteine residues on signaling targets or modulation of intracellular signaling pathways. Thus, in erythropoiesis, efficient cytoprotective systems are required to limit possible reactive oxygen species-related toxic effects especially in stress erythropoiesis characterized by severe oxidation such as β-thalassemia. In addition, prolonged or severe oxidative stress impairs autophagy, which might contribute to the block of erythroid maturation in stress erythropoiesis. Understanding the functional role of cytoprotective systems such as peroxiredoxin-2 or classical molecular chaperones such as the heat shock proteins will contribute to develop innovative therapeutic strategies for ineffective erythropoiesis. SUMMARY We provide an update on cytoprotective mechanisms against oxidation in normal and stress erythropoiesis. We discuss the role of oxidative sensors involved in modulation of intracellular signaling during erythroid maturation process in normal and stress erythropoiesis.
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Stage Specific Expression Pattern of Alpha-Hemoglobin-Stabilizing-Protein (AHSP) Portrayed in Erythroblast Chronology. Methods Protoc 2020; 3:mps3030046. [PMID: 32629835 PMCID: PMC7563766 DOI: 10.3390/mps3030046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 06/26/2020] [Accepted: 06/26/2020] [Indexed: 12/17/2022] Open
Abstract
During erythropoiesis, the molecular chaperone alpha-hemoglobin-stabilizing protein (AHSP) sequesters free alpha-hemoglobin (αHb) and prevents precipitation of excess αHb. While AHSP is linked to hereditary anemia, the pattern of expression during specific erythroblast stages is poorly understood. We investigated gene and protein expressions of AHSP throughout progressive maturation stages of erythroblasts in biphasic cultures of blood and bone marrow samples from healthy donors. Differentiating erythroblasts were periodically subjected to flow cytometry, Amnis imaging and RT-qPCR analyses. We made parallel in vivo validations from naive murine bone marrow cells. Percentages of AHSP+ erythroblasts, protein expressions and AHSP gene expressions are negligible on culture day 6 (CFU-Es) and progressively increases from culture days 8-12 (peaks on day 12) and declines on day 14. Notably, sub-cellular location of AHSP is both in the cytoplasm and nucleus in the early erythroblasts while in the late stages of maturation AHSP is found predominantly in the nucleus, being expelled with it during enucleation. As both human bone marrow and peripheral blood mononuclear cells (PBMC) derived erythroblasts demonstrated similar expression patterns, sampling of erythroblasts from day 11 cultures could portray erythroblast chronology and provide optimum representative stage specific expression patterns. PBMCs may be suitable for comparison studies of AHSP expression in pathologic erythropoiesi.
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Abdullah UYH, Ibrahim HM, Mahmud NB, Salleh MZ, Teh LK, Noorizhab MNFB, Zilfalil BA, Jassim HM, Wilairat P, Fucharoen S. Genotype-Phenotype Correlation of β-Thalassemia in Malaysian Population: Toward Effective Genetic Counseling. Hemoglobin 2020; 44:184-189. [PMID: 32586164 DOI: 10.1080/03630269.2020.1781652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Effective prevention of β-thalassemia (β-thal) requires strategies to detect at-risk couples. This is the first study attempting to assess the prevalence of silent β-thal carriers in the Malaysian population. Hematological and clinical parameters were evaluated in healthy blood donors and patients with β-thal trait, Hb E (HBB: c.79G>A)/β-thal and β-thal major (β-TM). β-Globin gene sequencing was carried out for 52 healthy blood donors, 48 patients with Hb E/β-thal, 34 patients with β-TM and 38 patients with β-thal trait. The prevalence of silent β-thal carrier phenotypes found in 25.0% of healthy Malaysian blood donors indicates the need for clinician's awareness of this type in evaluating β-thal in Malaysia. Patients with β-TM present at a significantly younger age at initial diagnosis and require more blood transfusions compared to those with Hb E/β-thal. The time at which genomic DNA was extracted after blood collection, particularly from patients with β-TM and Hb E/β-thal, was found to be an important determinant of the quality of the results of the β-globin sequencing. Public education and communication campaigns are recommended as apparently healthy individuals have few or no symptoms and normal or borderline hematological parameters. β-Globin gene mutation characterization and screening for silent β-thal carriers in regions prevalent with β-thal are recommended to develop more effective genetic counseling and management of β-thal.
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Affiliation(s)
- Uday Y H Abdullah
- Department of Pathology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Hishamshah M Ibrahim
- Paediatric Haematology, Oncology and Haemopoietic Stem Cell Transplant Unit, Hospital Kuala Lumpur (HKL) Jalan Pahang, Kuala Lumpur, Malaysia
| | - Noraesah Binti Mahmud
- Department of Pathology, Hospital Kuala Lumpur (HKL) Jalan Pahang, Kuala Lumpur, Malaysia
| | - Mohamad Zaki Salleh
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi Mara (UiTM), Bandar Puncak Alam, Malaysia
| | - Lay Kek Teh
- Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi Mara (UiTM), Bandar Puncak Alam, Malaysia
| | | | - Bin Alwi Zilfalil
- Department of Paediatric, School of Medical Science, Health Campus, Univesiti Sains Malaysia (USM), Kelantan, Malaysia
| | - Haitham Muhammed Jassim
- Department of Emergency, Rockingham Peel Group, South Metropolitan Health Service, Rockingham, Australia
| | - Prapin Wilairat
- National Doping Control Centre, Mahidol University, Bangkok, Thailand
| | - Suthat Fucharoen
- Thalassaemia Research Centre, Institute of Molecular Biosciences, Mahidol University, Nakornpathom, Thailand
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Che Yaacob NS, Islam MA, Alsaleh H, Ibrahim IK, Hassan R. Alpha-hemoglobin-stabilizing protein (AHSP): a modulatory factor in β-thalassemia. Int J Hematol 2020; 111:352-359. [PMID: 31894534 DOI: 10.1007/s12185-019-02806-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 11/30/2022]
Abstract
Hemoglobin (Hb) is an iron-containing metalloprotein that transports oxygen molecules from the lungs to the rest of the human body. Among the different variants of Hb, HbA1 is the most common and is composed of two alpha (αHb) and two beta globin chains (βHb) constructing a heterotetrameric protein complex (α2β2). Due to the higher number of AHSP genes, there is a tendency to produce approximately twice as much of α subunit as β subunit. Therefore, there is a chance of presenting excess α subunit leftover in human blood plasma; excess subunits subsequently bind with each other and aggregates β-thalassemia occurs due to lack of or reduced numbers of βHb subunit. Alpha-hemoglobin-stabilizing protein (AHSP) is a scavenger protein which acts as a molecular chaperon by reversibly binding with free αHb forming a complex (AHSP-αHb) that prevents aggregation and precipitation preventing deleterious effects towards developing serious human diseases including β-thalassemia. Clinical severity worsens if mutations in AHSP gene co-occur in patients with β-thalassemia. Considering the mechanism of action of AHSP and its contribution to ameliorating β-thalassemia severity, it could potentially be used as a modulatory agent in the treatment of β-thalassemia.
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Affiliation(s)
- Nur Suraya Che Yaacob
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Md Asiful Islam
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Heba Alsaleh
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia
| | - Ibrahim Khidir Ibrahim
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia.,Department of Haematology, Faculty of Medical Laboratory Sciences, Al-Neelain University, Khartoum, Sudan
| | - Rosline Hassan
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, 16150, Kubang Kerian, Kelantan, Malaysia.
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Manolova V, Nyffenegger N, Flace A, Altermatt P, Varol A, Doucerain C, Sundstrom H, Dürrenberger F. Oral ferroportin inhibitor ameliorates ineffective erythropoiesis in a model of β-thalassemia. J Clin Invest 2019; 130:491-506. [PMID: 31638596 PMCID: PMC6934209 DOI: 10.1172/jci129382] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 10/08/2019] [Indexed: 01/01/2023] Open
Abstract
β-Thalassemia is a genetic anemia caused by partial or complete loss of β-globin synthesis, leading to ineffective erythropoiesis and RBCs with a short life span. Currently, there is no efficacious oral medication modifying anemia for patients with β-thalassemia. The inappropriately low levels of the iron regulatory hormone hepcidin enable excessive iron absorption by ferroportin, the unique cellular iron exporter in mammals, leading to organ iron overload and associated morbidities. Correction of unbalanced iron absorption and recycling by induction of hepcidin synthesis or treatment with hepcidin mimetics ameliorates β-thalassemia. However, hepcidin modulation or replacement strategies currently in clinical development all require parenteral drug administration. We identified oral ferroportin inhibitors by screening a library of small molecular weight compounds for modulators of ferroportin internalization. Restricting iron availability by VIT-2763, the first clinical stage oral ferroportin inhibitor, ameliorated anemia and the dysregulated iron homeostasis in the Hbbth3/+ mouse model of β-thalassemia intermedia. VIT-2763 not only improved erythropoiesis but also corrected the proportions of myeloid precursors in spleens of Hbbth3/+ mice. VIT-2763 is currently being developed as an oral drug targeting ferroportin for the treatment of β-thalassemia.
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Bose D, Chakrabarti A. Chaperone potential of erythroid spectrin: Effects of hemoglobin interaction, macromolecular crowders, phosphorylation and glycation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:140267. [PMID: 31470132 DOI: 10.1016/j.bbapap.2019.140267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/09/2019] [Accepted: 08/24/2019] [Indexed: 10/26/2022]
Abstract
Spectrin, the major protein component of the erythrocyte membrane skeleton has chaperone like activity and is known to bind membrane phospholipids and hemoglobin. We have probed the chaperone activity of spectrin in presence of hemoglobin and phospholipid SUVs of different compositions to elucidate the effect of phospholipid/hemoglobin binding on chaperone function. It is seen that spectrin displays a preference for hemoglobin over other substrates leading to a decrease in chaperone activity in presence of hemoglobin. A competition is seen to exist between phospholipid binding and chaperone function of spectrin, in a dose dependent manner with the greatest extent of decrease being seen in case of phospholipid vesicles containing aminophospholipids e.g. PS and PE which may have implications in diseases like hereditary spherocytosis where mutation in spectrin is implicated in its detachment from cell membrane. To gain a clearer understanding of the chaperone like activity of spectrin under in-vivo like conditions we have investigated the effect of macromolecular crowders as well as phosphorylation and glycation states on chaperone activity. It is seen that the presence of non-specific, protein and non-protein macromolecular crowders do not appreciably affect chaperone function. Phosphorylation also does not affect the chaperone function unlike glycation which progressively diminishes chaperone activity. We propose a model where chaperone clients adsorb onto spectrin's surface and processes that bind to and occlude these surfaces decrease chaperone activity.
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Affiliation(s)
- Dipayan Bose
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India; Homi Bhabha National Institute, Mumbai 400094, India
| | - Abhijit Chakrabarti
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India; Homi Bhabha National Institute, Mumbai 400094, India.
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17
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Ghosh A, Stuehr DJ. Hsp90 and Its Role in Heme-Maturation of Client Proteins: Implications for Human Diseases. HEAT SHOCK PROTEINS 2019. [DOI: 10.1007/978-3-030-23158-3_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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18
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The effect of histone deacetylase inhibitors on AHSP expression. PLoS One 2018; 13:e0189267. [PMID: 29389946 PMCID: PMC5794076 DOI: 10.1371/journal.pone.0189267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 11/03/2017] [Indexed: 11/25/2022] Open
Abstract
Alpha-hemoglobin stabilizing protein (AHSP) is a molecular chaperone that can reduce the damage caused by excess free α-globin to erythroid cells in patients with impaired β-globin chain synthesis. We assessed the effect of sodium phenylbutyrate and sodium valproate, two histone deacetylase inhibitors (HDIs) that are being studied for the treatment of hemoglobinopathies, on the expression of AHSP, BCL11A (all isoforms), γ-globin genes (HBG1/2), and some related transcription factors including GATA1, NFE2, EKLF, KLF4, and STAT3. For this purpose, the K562 cell line was cultured for 2, 4, and 6 days in the presence and absence of sodium phenylbutyrate and sodium valproate. Relative real-time qRT-PCR analysis of mRNA levels was performed to determine the effects of the two compounds on gene expression. Expression of all target mRNAs increased significantly (p < 0.05), except for the expression of BCL11A, which was down-regulated (p < 0.05) in the cells treated with both compounds relative to the levels measured for untreated cells. The findings indicated that sodium valproate had a more considerable effect than sodium phenylbutyrate (p < 0.0005) on BCL11A repression and the up-regulation of other studied genes. γ-Globin and AHSP gene expression continuously increased during the culture period in the treated cells, with the highest gene expression observed for 1 mM sodium valproate after 6 days. Both compounds repressed the expression of BCL11A (-XL, -L, -S) and up-regulated GATA1, NFE2, EKLF, KLF4, STAT3, AHSP, and γ-globin genes expression. Moreover, sodium valproate showed a stronger effect on repressing BCL11A and escalating the expression of other target genes. The findings of this in vitro experiment could be considered in selecting drugs for clinical use in patients with β-hemoglobinopathies.
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19
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Hsp90 chaperones hemoglobin maturation in erythroid and nonerythroid cells. Proc Natl Acad Sci U S A 2018; 115:E1117-E1126. [PMID: 29358373 DOI: 10.1073/pnas.1717993115] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Maturation of adult (α2β2) and fetal hemoglobin (α2γ2) tetramers requires that heme be incorporated into each globin. While hemoglobin alpha (Hb-α) relies on a specific erythroid chaperone (alpha Hb-stabilizing protein, AHSP), the other chaperones that may help mature the partner globins (Hb-γ or Hb-β) in erythroid cells, or may enable nonerythroid cells to express mature Hb, are unknown. We investigated a role for heat-shock protein 90 (hsp90) in Hb maturation in erythroid precursor cells that naturally express Hb-α with either Hb-γ (K562 and HiDEP-1 cells) or Hb-β (HUDEP-2) and in nonerythroid cell lines that either endogenously express Hb-αβ (RAW and A549) or that we transfected to express the globins. We found the following: (i) AHSP and hsp90 associate with distinct globin partners in their immature heme-free states (AHSP with apo-Hbα, and hsp90 with apo-Hbβ or Hb-γ) and that hsp90 does not associate with mature Hb. (ii) Hsp90 stabilizes the apo-globins and helps to drive their heme insertion reactions, as judged by pharmacologic hsp90 inhibition or by coexpression of an ATP-ase defective hsp90. (iii) In nonerythroid cells, heme insertion into all globins became hsp90-dependent, which may explain how mixed Hb tetramers can mature in cells that do not express AHSP. Together, our findings uncover a process in which hsp90 first binds to immature, heme-free Hb-γ or Hb-β, drives their heme insertion process, and then dissociates to allow their heterotetramer formation with Hb-α. Thus, in driving heme insertion, hsp90 works in concert with AHSP to generate functional Hb tetramers during erythropoiesis.
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20
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Gell DA. Structure and function of haemoglobins. Blood Cells Mol Dis 2017; 70:13-42. [PMID: 29126700 DOI: 10.1016/j.bcmd.2017.10.006] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 12/18/2022]
Abstract
Haemoglobin (Hb) is widely known as the iron-containing protein in blood that is essential for O2 transport in mammals. Less widely recognised is that erythrocyte Hb belongs to a large family of Hb proteins with members distributed across all three domains of life-bacteria, archaea and eukaryotes. This review, aimed chiefly at researchers new to the field, attempts a broad overview of the diversity, and common features, in Hb structure and function. Topics include structural and functional classification of Hbs; principles of O2 binding affinity and selectivity between O2/NO/CO and other small ligands; hexacoordinate (containing bis-imidazole coordinated haem) Hbs; bacterial truncated Hbs; flavohaemoglobins; enzymatic reactions of Hbs with bioactive gases, particularly NO, and protection from nitrosative stress; and, sensor Hbs. A final section sketches the evolution of work on the structural basis for allosteric O2 binding by mammalian RBC Hb, including the development of newer kinetic models. Where possible, reference to historical works is included, in order to provide context for current advances in Hb research.
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Affiliation(s)
- David A Gell
- School of Medicine, University of Tasmania, TAS 7000, Australia.
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21
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Surapolchai P, Chuansumrit A, Sirachainan N, Kadegasem P, Leung KC, So CC. A molecular study on the role of alpha-hemoglobin-stabilizing protein in hemoglobin H disease. Ann Hematol 2017; 96:1005-1014. [DOI: 10.1007/s00277-017-2978-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 03/09/2017] [Indexed: 11/24/2022]
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22
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Arlet JB, Guillem F, Lamarque M, Dussiot M, Maciel T, Moura I, Hermine O, Courtois G. Protein-based therapeutic for anemia caused by dyserythropoiesis. Expert Rev Proteomics 2016; 13:983-992. [PMID: 27661264 DOI: 10.1080/14789450.2016.1240622] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Major advances have been recently made in understanding the molecular determinants of dyserythropoiesis, particularly due to recent works in β-thalassemia. The purpose of this review is devoted to underline the role of some proteins recently evidenced in the field, that may be new alternative therapeutic targets in the near future to alleviate different types of anemia. Areas covered: This review covers the contemporary aspects of some proteins involved in various types of dyserythropoiesis, including the transcriptional factor GATA-1 and its protective chaperone HSP70, but also cytokines of the transforming growth factor beta (TFG-β) family, TGF-β1 and GDF-11, and hormones as erythroferrone. It will be not exhaustive, but based on major recent published works from the literature in the past three years. Expert commentary: Sotatercept and lustatercept, two activin receptor II ligand traps that block GDF-11, are candidate drugs providing therapeutic hope in different types of ineffective erythropoiesis, including myelodysplastic syndromes (MDS) and β-thalassemia. Furthermore, a new concept emerges to consider erythroid lineage in the bone marrow as an endocrine gland.
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Affiliation(s)
- Jean-Benoît Arlet
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,b Service de Médecine Interne, Faculté de Médecine Paris Descartes, Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris , Hôpital européen Georges Pompidou , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Flavia Guillem
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Mathilde Lamarque
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France.,e Service d'Hématologie, Faculté de Médecine Paris Descartes , Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris Hôpital Necker , Paris , France
| | - Michael Dussiot
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Thiago Maciel
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Ivan Moura
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Olivier Hermine
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France.,e Service d'Hématologie, Faculté de Médecine Paris Descartes , Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris Hôpital Necker , Paris , France
| | - Geneviève Courtois
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
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Tanimura N, Miller E, Igarashi K, Yang D, Burstyn JN, Dewey CN, Bresnick EH. Mechanism governing heme synthesis reveals a GATA factor/heme circuit that controls differentiation. EMBO Rep 2015; 17:249-65. [PMID: 26698166 DOI: 10.15252/embr.201541465] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 11/24/2015] [Indexed: 12/18/2022] Open
Abstract
Metal ion-containing macromolecules have fundamental roles in essentially all biological processes throughout the evolutionary tree. For example, iron-containing heme is a cofactor in enzyme catalysis and electron transfer and an essential hemoglobin constituent. To meet the intense demand for hemoglobin assembly in red blood cells, the cell type-specific factor GATA-1 activates transcription of Alas2, encoding the rate-limiting enzyme in heme biosynthesis, 5-aminolevulinic acid synthase-2 (ALAS-2). Using genetic editing to unravel mechanisms governing heme biosynthesis, we discovered a GATA factor- and heme-dependent circuit that establishes the erythroid cell transcriptome. CRISPR/Cas9-mediated ablation of two Alas2 intronic cis elements strongly reduces GATA-1-induced Alas2 transcription, heme biosynthesis, and surprisingly, GATA-1 regulation of other vital constituents of the erythroid cell transcriptome. Bypassing ALAS-2 function in Alas2 cis element-mutant cells by providing its catalytic product 5-aminolevulinic acid rescues heme biosynthesis and the GATA-1-dependent genetic network. Heme amplifies GATA-1 function by downregulating the heme-sensing transcriptional repressor Bach1 and via a Bach1-insensitive mechanism. Through this dual mechanism, heme and a master regulator collaborate to orchestrate a cell type-specific transcriptional program that promotes cellular differentiation.
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Affiliation(s)
- Nobuyuki Tanimura
- Department of Cell and Regenerative Biology, UW-Madison Blood Research Program, Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Eli Miller
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Kazuhiko Igarashi
- Department of Biochemistry, Tohoku University School of Medicine, Sendai, Japan
| | - David Yang
- Department of Pathology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Judith N Burstyn
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Colin N Dewey
- Department of Biostatistics and Medical Informatics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Emery H Bresnick
- Department of Cell and Regenerative Biology, UW-Madison Blood Research Program, Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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Mettananda S, Gibbons RJ, Higgs DR. Understanding α-globin gene regulation and implications for the treatment of β-thalassemia. Ann N Y Acad Sci 2015; 1368:16-24. [PMID: 26695885 DOI: 10.1111/nyas.12988] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Over the past three decades, a vast amount of new information has been uncovered describing how the globin genes are regulated. This knowledge has provided significant insights into the general understanding of the regulation of human genes. It is now known that molecular defects within and around the α- and β-globin genes, as well as in the distant regulatory elements, can cause thalassemia. Unbalanced production of globin chains owing to defective synthesis of one, and the continued unopposed synthesis of another, is the central causative factor in the cellular pathology and pathophysiology of thalassemia. A large body of clinical, genetic, and experimental evidence suggests that altering globin chain imbalance by reducing the production of α-globin synthesis ameliorates the disease severity in patients with β-thalassemia. With the development of new genetic-based therapeutic tools that have a potential to decrease the expression of a selected gene in a tissue-specific manner, the possibility of decreasing expression of the α-globin gene to improve the clinical severity of β-thalassemia could become a reality.
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Affiliation(s)
- Sachith Mettananda
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.,Department of Pediatrics, Faculty of Medicine, University of Kelaniya, Sri Lanka
| | - Richard J Gibbons
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Douglas R Higgs
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.,Oxford National Institute for Health Research Biomedical Research Centre, Blood Theme, Oxford University Hospital, Oxford, United Kingdom
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Mahmoud HM, Shoeib AASH, Abd El Ghany SM, Reda MM, Ragab IA. Study of alpha hemoglobin stabilizing protein expression in patients with β thalassemia and sickle cell anemia and its impact on clinical severity. Blood Cells Mol Dis 2015; 55:358-62. [DOI: 10.1016/j.bcmd.2015.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 07/28/2015] [Accepted: 07/29/2015] [Indexed: 11/29/2022]
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Voskou S, Aslan M, Fanis P, Phylactides M, Kleanthous M. Oxidative stress in β-thalassaemia and sickle cell disease. Redox Biol 2015; 6:226-239. [PMID: 26285072 PMCID: PMC4543215 DOI: 10.1016/j.redox.2015.07.018] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 12/21/2022] Open
Abstract
Sickle cell disease and β-thalassaemia are inherited haemoglobinopathies resulting in structural and quantitative changes in the β-globin chain. These changes lead to instability of the generated haemoglobin or to globin chain imbalance, which in turn impact the oxidative environment both intracellularly and extracellularly. The ensuing oxidative stress and the inability of the body to adequately overcome it are, to a large extent, responsible for the pathophysiology of these diseases. This article provides an overview of the main players and control mechanisms involved in the establishment of oxidative stress in these haemoglobinopathies.
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Affiliation(s)
- S Voskou
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - M Aslan
- Akdeniz University, Faculty of Medicine, Department of Medical Biochemistry, Antalya, Turkey
| | - P Fanis
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - M Phylactides
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.
| | - M Kleanthous
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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α-Globin as a molecular target in the treatment of β-thalassemia. Blood 2015; 125:3694-701. [PMID: 25869286 DOI: 10.1182/blood-2015-03-633594] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 03/31/2015] [Indexed: 12/31/2022] Open
Abstract
The thalassemias, together with sickle cell anemia and its variants, are the world's most common form of inherited anemia, and in economically undeveloped countries, they still account for tens of thousands of premature deaths every year. In developed countries, treatment of thalassemia is also still far from ideal, requiring lifelong transfusion or allogeneic bone marrow transplantation. Clinical and molecular genetic studies over the course of the last 50 years have demonstrated how coinheritance of modifier genes, which alter the balance of α-like and β-like globin gene expression, may transform severe, transfusion-dependent thalassemia into relatively mild forms of anemia. Most attention has been paid to pathways that increase γ-globin expression, and hence the production of fetal hemoglobin. Here we review the evidence that reduction of α-globin expression may provide an equally plausible approach to ameliorating clinically severe forms of β-thalassemia, and in particular, the very common subgroup of patients with hemoglobin E β-thalassemia that makes up approximately half of all patients born each year with severe β-thalassemia.
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Vasseur C, Baudin-Creuza V. [Role of alpha-hemoglobin molecular chaperone in the hemoglobin formation and clinical expression of some hemoglobinopathies]. Transfus Clin Biol 2015; 22:49-57. [PMID: 25724329 DOI: 10.1016/j.tracli.2015.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 01/21/2015] [Indexed: 10/24/2022]
Abstract
Alpha-hemoglobin stabilizing protein (AHSP), described as a chaperone of alpha-hemoglobin (α-Hb), is synthesized at a high concentration in the erythroid precursors. AHSP specifically recognizes the G and H helices of α-Hb and forms a stable complex with free α-Hb until its association with the partner β-subunits. Unlike the free β-Hb which are soluble and form homologous tetramers, freshly synthesized α-Hb chains are highly unstable molecular species which precipitate and generate reactive oxygen species within the erythrocyte precursors of the bone marrow leading to apoptosis and ineffective erythropoiesis. AHSP protects the free α-Hb chains in maintaining it in the soluble state. In this review, we report data from the literature and our laboratory concerning the key role of AHSP in the biosynthesis of Hb and its possible involvement in some disorders of the red blood cell as well as the hemoglobinopathies and we discuss its use as a prognostic tool in thalassemia syndromes.
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Affiliation(s)
- C Vasseur
- Institut national de la santé et de la recherche médicale (INSERM) U955, équipe 2, université Paris Est Créteil, 5, avenue Gustave-Eiffel, 94000 Créteil, France; Laboratoire d'excellence des globules rouges (GR-EX), 75015 Paris, France
| | - V Baudin-Creuza
- Institut national de la santé et de la recherche médicale (INSERM) U955, équipe 2, université Paris Est Créteil, 5, avenue Gustave-Eiffel, 94000 Créteil, France; Laboratoire d'excellence des globules rouges (GR-EX), 75015 Paris, France.
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Gelderman MP, Baek JH, Yalamanoglu A, Puglia M, Vallelian F, Burla B, Vostal J, Schaer DJ, Buehler PW. Reversal of hemochromatosis by apotransferrin in non-transfused and transfused Hbbth3/+ (heterozygous B1/B2 globin gene deletion) mice. Haematologica 2015; 100:611-22. [PMID: 25616571 DOI: 10.3324/haematol.2014.117325] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 01/20/2015] [Indexed: 01/17/2023] Open
Abstract
Intermediate beta-thalassemia has a broad spectrum of sequelae and affected subjects may require occasional blood transfusions over their lifetime to correct anemia. Iron overload in intermediate beta-thalassemia results from a paradoxical intestinal absorption, iron release from macrophages and hepatocytes, and sporadic transfusions. Pathological iron accumulation in parenchyma is caused by chronic exposure to non-transferrin bound iron in plasma. The iron scavenger and transport protein transferrin is a potential treatment being studied for correction of anemia. However, transferrin may also function to prevent or reduce iron loading of tissues when exposure to non-transferrin bound iron increases. Here we evaluate the effects of apotransferrin administration on tissue iron loading and early tissue pathology in non-transfused and transfused Hbb(th3/+) mice. Mice with the Hbb(th3/+) phenotype have mild to moderate anemia and consistent tissue iron accumulation in the spleen, liver, kidneys and myocardium. Chronic apotransferrin administration resulted in normalization of the anemia. Furthermore, it normalized tissue iron content in the liver, kidney and heart and attenuated early tissue changes in non-transfused Hbb(th3/+) mice. Apotransferrin treatment was also found to attenuate transfusion-mediated increases in plasma non-transferrin bound iron and associated excess tissue iron loading. These therapeutic effects were associated with normalization of transferrin saturation and suppressed plasma non-transferrin bound iron. Apotransferrin treatment modulated a fundamental iron regulatory pathway, as evidenced by decreased erythroid Fam132b gene (erythroferrone) expression, increased liver hepcidin gene expression and plasma hepcidin-25 levels and consequently reduced intestinal ferroportin-1 in apotransferrin-treated thalassemic mice.
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Affiliation(s)
- Monique P Gelderman
- Laboratory of Biochemistry and Vascular Biology, Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD, USA
| | - Jin Hyen Baek
- Laboratory of Cellular Hematology, Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD, USA
| | - Ayla Yalamanoglu
- Laboratory of Cellular Hematology, Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD, USA Division of Internal Medicine, University of Zurich, Switzerland
| | - Michele Puglia
- Functional Genomics Center Zurich, Swiss Federal Institute of Technology Zurich / University of Zurich, Switzerland Division of Internal Medicine, University of Zurich, Switzerland
| | | | - Bo Burla
- Division of Internal Medicine, University of Zurich, Switzerland
| | - Jaroslav Vostal
- Laboratory of Biochemistry and Vascular Biology, Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD, USA
| | - Dominik J Schaer
- Division of Internal Medicine, University of Zurich, Switzerland Center of Evolutionary Medicine, University of Zurich, Switzerland
| | - Paul W Buehler
- Laboratory of Cellular Hematology, Center of Biologics Evaluation and Research (CBER), FDA, Silver Spring, MD, USA
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Sumera A, Radhakrishnan A, Baba AA, George E. Review: Beta-thalassemia and molecular chaperones. Blood Cells Mol Dis 2015; 54:348-52. [PMID: 25648458 DOI: 10.1016/j.bcmd.2015.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 01/11/2015] [Indexed: 12/31/2022]
Abstract
Thalassemia is known as a diverse single gene disorder, which is prevalent worldwide. The molecular chaperones are set of proteins that help in two important processes while protein synthesis and degradation include folding or unfolding and assembly or disassembly, thereby helping in cell homeostasis. This review recaps current knowledge regarding the role of molecular chaperones in thalassemia, with a focus on beta thalassemia.
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Affiliation(s)
- Afshan Sumera
- Department of Pathology, School of Medicine, International Medical University, Kuala Lumpur, Malaysia.
| | - Ammu Radhakrishnan
- Department of Pathology, School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| | - Abdul Aziz Baba
- Department of Pathology, School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| | - Elizabeth George
- Department of Pathology, University Putra Malaysia, Kuala Lumpur, Malaysia
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Kattamis A, Delaporta P, Fylaktou I, Vrettou C, Kyriakopoulou D, Stamoulakatou A, Papassotiriou I, Kanavakis E, Traeger-Synodinos J. Hb Souli, a 6 bp in-frame deletion on the HBA2 gene (HBA2: c.[41-46delCCTGGG]) leads to α-thalassemia intermedia, when in trans to a single α-globin gene deletion. Hemoglobin 2014; 39:55-7. [PMID: 25476779 DOI: 10.3109/03630269.2014.981827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We report the case of a 5-year-old child with clinical and hematological findings consistent with the diagnosis of α-thalassemia intermedia (α-TI). Molecular analysis disclosed the common 3.7 kb deletion in the α-globin gene cluster in trans to a novel in-frame 6 bp deletion in the HBA2 gene. It removes the sequence CCTGGG (or GCCTGG) that normally encodes for alanine (codon 13) and tryptophan (codon 14). Even though several hemoglobin (Hb) variants with mutations affecting codons 13 or 14 have been described, Hb Souli (HBA2: c.[41-46delCCTGGG]) is, to the best of our knowledge, the first variant to be reported where both amino acid residues, α13Ala and α14Trp, are deleted, leading to unstable and rapidly degraded α-globin chains.
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Affiliation(s)
- Antonis Kattamis
- First Department of Pediatrics, Athens University Medical School , Athens , Greece
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Role of α-globin H helix in the building of tetrameric human hemoglobin: interaction with α-hemoglobin stabilizing protein (AHSP) and heme molecule. PLoS One 2014; 9:e111395. [PMID: 25369055 PMCID: PMC4219717 DOI: 10.1371/journal.pone.0111395] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/23/2014] [Indexed: 11/25/2022] Open
Abstract
Alpha-Hemoglobin Stabilizing Protein (AHSP) binds to α-hemoglobin (α-Hb) or α-globin and maintains it in a soluble state until its association with the β-Hb chain partner to form Hb tetramers. AHSP specifically recognizes the G and H helices of α-Hb. To investigate the degree of interaction of the various regions of the α-globin H helix with AHSP, this interface was studied by stepwise elimination of regions of the α-globin H helix: five truncated α-Hbs α-Hb1-138, α-Hb1-134, α-Hb1-126, α-Hb1-123, α-Hb1-117 were co-expressed with AHSP as two glutathione-S-transferase (GST) fusion proteins. SDS-PAGE and Western Blot analysis revealed that the level of expression of each truncated α-Hb was similar to that of the wild type α-Hb except the shortest protein α-Hb1-117 which displayed a decreased expression. While truncated GST-α-Hb1-138 and GST-α-Hb1-134 were normally soluble; the shorter globins GST-α-Hb1-126 and GST-α-Hb1-117 were obtained in very low quantities, and the truncated GST-α-Hb1-123 provided the least material. Absorbance and fluorescence studies of complexes showed that the truncated α-Hb1-134 and shorter forms led to modified absorption spectra together with an increased fluorescence emission. This attests that shortening the H helix leads to a lower affinity of the α-globin for the heme. Upon addition of β-Hb, the increase in fluorescence indicates the replacement of AHSP by β-Hb. The CO binding kinetics of different truncated AHSPWT/α-Hb complexes showed that these Hbs were not functionally normal in terms of the allosteric transition. The N-terminal part of the H helix is primordial for interaction with AHSP and C-terminal part for interaction with heme, both features being required for stability of α-globin chain.
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Cao C, Zhao G, Yu W, Xie X, Wang W, Yang R, Lv X, Liu D. Activation of STAT3 stimulates AHSP expression in K562 cells. SCIENCE CHINA-LIFE SCIENCES 2014; 57:488-94. [DOI: 10.1007/s11427-014-4652-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 01/05/2014] [Indexed: 02/04/2023]
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Dussiot M, Maciel TT, Fricot A, Chartier C, Negre O, Veiga J, Grapton D, Paubelle E, Payen E, Beuzard Y, Leboulch P, Ribeil JA, Arlet JB, Coté F, Courtois G, Ginzburg YZ, Daniel TO, Chopra R, Sung V, Hermine O, Moura IC. An activin receptor IIA ligand trap corrects ineffective erythropoiesis in β-thalassemia. Nat Med 2014; 20:398-407. [PMID: 24658077 PMCID: PMC7730561 DOI: 10.1038/nm.3468] [Citation(s) in RCA: 220] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 01/10/2014] [Indexed: 02/06/2023]
Abstract
The pathophysiology of ineffective erythropoiesis in β-thalassemia is poorly understood. We report that RAP-011, an activin receptor IIA (ActRIIA) ligand trap, improved ineffective erythropoiesis, corrected anemia and limited iron overload in a mouse model of β-thalassemia intermedia. Expression of growth differentiation factor 11 (GDF11), an ActRIIA ligand, was increased in splenic erythroblasts from thalassemic mice and in erythroblasts and sera from subjects with β-thalassemia. Inactivation of GDF11 decreased oxidative stress and the amount of α-globin membrane precipitates, resulting in increased terminal erythroid differentiation. Abnormal GDF11 expression was dependent on reactive oxygen species, suggesting the existence of an autocrine amplification loop in β-thalassemia. GDF11 inactivation also corrected the abnormal ratio of immature/mature erythroblasts by inducing apoptosis of immature erythroblasts through the Fas-Fas ligand pathway. Taken together, these observations suggest that ActRIIA ligand traps may have therapeutic relevance in β-thalassemia by suppressing the deleterious effects of GDF11, a cytokine which blocks terminal erythroid maturation through an autocrine amplification loop involving oxidative stress and α-globin precipitation.
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Affiliation(s)
- Michael Dussiot
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France. [6]
| | - Thiago T Maciel
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France. [6]
| | - Aurélie Fricot
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France
| | - Céline Chartier
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France
| | - Olivier Negre
- 1] Commissariat à l'Energie Atomique (CEA)-Institut des Maladies Emergentes et des Thérapies Innovantes (iMETI), Fontenay-aux-Roses, France. [2] UMR 962 (Inserm-CEA-University of Paris-Sud), Fontenay-aux-Roses, France
| | - Joel Veiga
- Laboratory of Excellence GR-Ex, Paris, France
| | - Damien Grapton
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France
| | - Etienne Paubelle
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France
| | - Emmanuel Payen
- 1] Commissariat à l'Energie Atomique (CEA)-Institut des Maladies Emergentes et des Thérapies Innovantes (iMETI), Fontenay-aux-Roses, France. [2] UMR 962 (Inserm-CEA-University of Paris-Sud), Fontenay-aux-Roses, France
| | - Yves Beuzard
- 1] Commissariat à l'Energie Atomique (CEA)-Institut des Maladies Emergentes et des Thérapies Innovantes (iMETI), Fontenay-aux-Roses, France. [2] UMR 962 (Inserm-CEA-University of Paris-Sud), Fontenay-aux-Roses, France
| | - Philippe Leboulch
- 1] Commissariat à l'Energie Atomique (CEA)-Institut des Maladies Emergentes et des Thérapies Innovantes (iMETI), Fontenay-aux-Roses, France. [2] UMR 962 (Inserm-CEA-University of Paris-Sud), Fontenay-aux-Roses, France
| | - Jean-Antoine Ribeil
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] Département de Biothérapie, Hôpital Necker-Enfants Malades, Paris, France
| | - Jean-Benoit Arlet
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France
| | - Francine Coté
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France
| | - Geneviève Courtois
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France
| | - Yelena Z Ginzburg
- Erythropoiesis Laboratory, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, USA
| | | | | | | | - Olivier Hermine
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] Service d'Hématologie Clinique, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, Paris, France
| | - Ivan C Moura
- 1] INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France. [2] Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France. [3] CNRS ERL 8254, Paris, France. [4] Laboratory of Excellence GR-Ex, Paris, France. [5] INSERM U1149, Center for Research on Inflammation, Paris, France
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Modulation of hepcidin as therapy for primary and secondary iron overload disorders: preclinical models and approaches. Hematol Oncol Clin North Am 2014; 28:387-401. [PMID: 24589273 DOI: 10.1016/j.hoc.2013.11.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this article, the authors discuss new approaches to treating iron overload diseases using hepcidin mimetics or by modulating endogenous hepcidin expression. In particular, the authors discuss lipid nanoparticle encapsulated siRNA and antisense oligonucleotide-mediated inhibition of TMPRSS6, an upstream regulator of hepcidin, and treatment with transferrin or hepcidin mimetics, including the recently described minihepcidins. In each case, in animal models of β-thalassemia, not only do the interventions affect iron absorption but they also act as disease-modifying agents that ameliorate the ineffective erythropoiesis.
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36
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Kiger L, Vasseur C, Domingues-Hamdi E, Truan G, Marden MC, Baudin-Creuza V. Dynamics of α-Hb chain binding to its chaperone AHSP depends on heme coordination and redox state. Biochim Biophys Acta Gen Subj 2014; 1840:277-87. [DOI: 10.1016/j.bbagen.2013.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 09/06/2013] [Accepted: 09/09/2013] [Indexed: 11/27/2022]
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Mitchell A, Guan W, Staggs R, Hamel A, Hozayen S, Adhikari N, Grindle S, Desir S, John R, Hall JL, Eckman P. Identification of differentially expressed transcripts and pathways in blood one week and six months following implant of left ventricular assist devices. PLoS One 2013; 8:e77951. [PMID: 24205042 PMCID: PMC3804545 DOI: 10.1371/journal.pone.0077951] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 09/06/2013] [Indexed: 11/19/2022] Open
Abstract
Introduction Continuous-flow left ventricular assist devices (LVADs) are an established therapy for patients with end-stage heart failure. The short- and long-term impact of these devices on peripheral blood gene expression has not been characterized, and may provide insight into the molecular pathways mediated in response to left ventricular remodeling and an improvement in overall systemic circulation. We performed RNA sequencing to identify genes and pathways influenced by these devices. Methods RNA was extracted from blood of 9 heart failure patients (8 male) prior to LVAD implantation, and at 7 and 180 days postoperatively. Libraries were sequenced on an Illumina HiSeq2000 and sequences mapped to the human Ensembl GRCh37.67 genome assembly. Results A specific set of genes involved in regulating cellular immune response, antigen presentation, and T cell activation and survival were down-regulated 7 days after LVAD placement. 6 months following LVAD placement, the expression levels of these genes were significantly increased; yet importantly, remained significantly lower than age and sex-matched samples from healthy controls. Conclusions In summary, this genomic analysis identified a significant decrease in the expression of genes that promote a healthy immune response in patients with heart failure that was partially restored 6 months following LVAD implant.
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Affiliation(s)
- Adam Mitchell
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- Division of Cardiology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Weihua Guan
- Division of Biostatistics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Rodney Staggs
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- Division of Cardiology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Aimee Hamel
- Lillehei Clinical Research Unit, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Sameh Hozayen
- Division of Cardiology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Neeta Adhikari
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Suzanne Grindle
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Snider Desir
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Ranjit John
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jennifer L. Hall
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- Division of Cardiology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail: (JH); (PE)
| | - Peter Eckman
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- Division of Cardiology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail: (JH); (PE)
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Oxidative stress and β-thalassemic erythroid cells behind the molecular defect. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:985210. [PMID: 24205432 PMCID: PMC3800594 DOI: 10.1155/2013/985210] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 06/04/2013] [Indexed: 11/18/2022]
Abstract
β-thalassemia is a worldwide distributed monogenic red cell disorder, characterized by the absence or reduced β-globin chain synthesis. Despite the extensive knowledge of the molecular defects causing β-thalassemia, less is known about the mechanisms responsible for the associated ineffective erythropoiesis and reduced red cell survival, which sustain anemia of β-thalassemia. The unbalance of alpha-gamma chain and the presence of pathological free iron promote a severe red cell membrane oxidative stress, which results in abnormal β-thalassemic red cell features. These cells are precociously removed by the macrophage system through two mechanisms: the removal of phosphatidylserine positive cells and through the natural occurring antibody produced against the abnormally clustered membrane protein band 3. In the present review we will discuss the changes in β-thalassemic red cell homeostasis related to the oxidative stress and its connection with production of microparticles and with malaria infection. The reactive oxygen species (ROS) are also involved in ineffective erythropoiesis of β-thalassemia through still partially known pathways. Novel cytoprotective systems such as ASHP, eIF2α, and peroxiredoxin-2 have been suggested to be important against ROS in β-thalassemic erythropoiesis. Finally, we will discuss the results of the major in vitro and in vivo studies with antioxidants in β-thalassemia.
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Nikolov IG, Joki N, Galmiche A, Nguyen-Khoa T, Guerrera IC, Guillonneau F, Ivanovski O, Phan O, Maizel J, Marçon F, Benchitrit J, Lucas A, Edelman A, Lacour B, Drüeke TB, Massy ZA. Farnesyltransferase inhibitor R115777 protects against vascular disease in uremic mice. Atherosclerosis 2013; 229:42-51. [DOI: 10.1016/j.atherosclerosis.2013.02.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 02/08/2013] [Accepted: 02/25/2013] [Indexed: 11/26/2022]
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Varnado CL, Mollan TL, Birukou I, Smith BJ, Henderson DP, Olson JS. Development of recombinant hemoglobin-based oxygen carriers. Antioxid Redox Signal 2013; 18:2314-28. [PMID: 23025383 PMCID: PMC3638513 DOI: 10.1089/ars.2012.4917] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 09/23/2012] [Accepted: 10/01/2012] [Indexed: 12/27/2022]
Abstract
SIGNIFICANCE The worldwide blood shortage has generated a significant demand for alternatives to whole blood and packed red blood cells for use in transfusion therapy. One such alternative involves the use of acellular recombinant hemoglobin (Hb) as an oxygen carrier. RECENT ADVANCES Large amounts of recombinant human Hb can be expressed and purified from transgenic Escherichia coli. The physiological suitability of this material can be enhanced using protein-engineering strategies to address specific efficacy and toxicity issues. Mutagenesis of Hb can (i) adjust dioxygen affinity over a 100-fold range, (ii) reduce nitric oxide (NO) scavenging over 30-fold without compromising dioxygen binding, (iii) slow the rate of autooxidation, (iv) slow the rate of hemin loss, (v) impede subunit dissociation, and (vi) diminish irreversible subunit denaturation. Recombinant Hb production is potentially unlimited and readily subjected to current good manufacturing practices, but may be restricted by cost. Acellular Hb-based O(2) carriers have superior shelf-life compared to red blood cells, are universally compatible, and provide an alternative for patients for whom no other alternative blood products are available or acceptable. CRITICAL ISSUES Remaining objectives include increasing Hb stability, mitigating iron-catalyzed and iron-centered oxidative reactivity, lowering the rate of hemin loss, and lowering the costs of expression and purification. Although many mutations and chemical modifications have been proposed to address these issues, the precise ensemble of mutations has not yet been identified. FUTURE DIRECTIONS Future studies are aimed at selecting various combinations of mutations that can reduce NO scavenging, autooxidation, oxidative degradation, and denaturation without compromising O(2) delivery, and then investigating their suitability and safety in vivo.
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Affiliation(s)
| | - Todd L. Mollan
- Center for Biologics Evaluation and Research, Division of Hematology, United States Food and Drug Administration, Bethesda, Maryland
| | - Ivan Birukou
- Department of Biochemistry, Duke University, Durham, North Carolina
| | - Bryan J.Z. Smith
- Department of Biology, The University of Texas of the Permian Basin, Odessa, Texas
| | - Douglas P. Henderson
- Department of Biology, The University of Texas of the Permian Basin, Odessa, Texas
| | - John S. Olson
- Department of Biochemistry & Cell Biology, Rice University, Houston, Texas
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Dickson CF, Rich AM, D'Avigdor WMH, Collins DAT, Lowry JA, Mollan TL, Khandros E, Olson JS, Weiss MJ, Mackay JP, Lay PA, Gell DA. α-Hemoglobin-stabilizing protein (AHSP) perturbs the proximal heme pocket of oxy-α-hemoglobin and weakens the iron-oxygen bond. J Biol Chem 2013; 288:19986-20001. [PMID: 23696640 DOI: 10.1074/jbc.m112.437509] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
α-Hemoglobin (αHb)-stabilizing protein (AHSP) is a molecular chaperone that assists hemoglobin assembly. AHSP induces changes in αHb heme coordination, but how these changes are facilitated by interactions at the αHb·AHSP interface is not well understood. To address this question we have used NMR, x-ray absorption spectroscopy, and ligand binding measurements to probe αHb conformational changes induced by AHSP binding. NMR chemical shift analyses of free CO-αHb and CO-αHb·AHSP indicated that the seven helical elements of the native αHb structure are retained and that the heme Fe(II) remains coordinated to the proximal His-87 side chain. However, chemical shift differences revealed alterations of the F, G, and H helices and the heme pocket of CO-αHb bound to AHSP. Comparisons of iron-ligand geometry using extended x-ray absorption fine structure spectroscopy showed that AHSP binding induces a small 0.03 Å lengthening of the Fe-O2 bond, explaining previous reports that AHSP decreases αHb O2 affinity roughly 4-fold and promotes autooxidation due primarily to a 3-4-fold increase in the rate of O2 dissociation. Pro-30 mutations diminished NMR chemical shift changes in the proximal heme pocket, restored normal O2 dissociation rate and equilibrium constants, and reduced O2-αHb autooxidation rates. Thus, the contacts mediated by Pro-30 in wild-type AHSP promote αHb autooxidation by introducing strain into the proximal heme pocket. As a chaperone, AHSP facilitates rapid assembly of αHb into Hb when βHb is abundant but diverts αHb to a redox resistant holding state when βHb is limiting.
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Affiliation(s)
- Claire F Dickson
- Menzies Research Institute Tasmania, University of Tasmania, Hobart, TAS 7000, Australia
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Ineffective erythropoiesis in β -thalassemia. ScientificWorldJournal 2013; 2013:394295. [PMID: 23606813 PMCID: PMC3628659 DOI: 10.1155/2013/394295] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 02/03/2013] [Indexed: 01/06/2023] Open
Abstract
In humans, β-thalassemia dyserythropoiesis is characterized by expansion of early erythroid precursors and erythroid progenitors and then ineffective erythropoiesis. This ineffective erythropoiesis is defined as a suboptimal production of mature erythrocytes originating from a proliferating pool of immature erythroblasts. It is characterized by (1) accelerated erythroid differentiation, (2) maturation blockade at the polychromatophilic stage, and (3) death of erythroid precursors. Despite extensive knowledge of molecular defects causing β-thalassemia, less is known about the mechanisms responsible for ineffective erythropoiesis. In this paper, we will focus on the underlying mechanisms leading to premature death of thalassemic erythroid precursors in the bone marrow.
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Nienhuis AW, Nathan DG. Pathophysiology and Clinical Manifestations of the β-Thalassemias. Cold Spring Harb Perspect Med 2012; 2:a011726. [PMID: 23209183 DOI: 10.1101/cshperspect.a011726] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The β-thalassemia syndromes reflect deficient or absent β-globin synthesis usually owing to a mutation in the β-globin locus. The relative excess of α-globin results in the formation of insoluble aggregates leading to ineffective erythropoiesis and shortened red cell survival. A relatively high capacity for fetal hemoglobin synthesis is a major genetic modifier of disease severity, with polymorphisms in other genes also having a significant role. Iron overload secondary to enhanced absorption and red cell transfusions causes an increase in liver iron and in various other tissues, leading to endocrine and cardiac dysfunction. Modern chelation regimens are effective in removing iron and preserving or restoring organ function.
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Affiliation(s)
- Arthur W Nienhuis
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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Integrated protein quality-control pathways regulate free α-globin in murine β-thalassemia. Blood 2012; 119:5265-75. [PMID: 22427201 DOI: 10.1182/blood-2011-12-397729] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cells remove unstable polypeptides through protein quality-control (PQC) pathways such as ubiquitin-mediated proteolysis and autophagy. In the present study, we investigated how these pathways are used in β-thalassemia, a common hemoglobinopathy in which β-globin gene mutations cause the accumulation and precipitation of cytotoxic α-globin subunits. In β-thalassemic erythrocyte precursors, free α-globin was polyubiquitinated and degraded by the proteasome. These cells exhibited enhanced proteasome activity, and transcriptional profiling revealed coordinated induction of most proteasome subunits that was mediated by the stress-response transcription factor Nrf1. In isolated thalassemic cells, short-term proteasome inhibition blocked the degradation of free α-globin. In contrast, prolonged in vivo treatment of β-thalassemic mice with the proteasome inhibitor bortezomib did not enhance the accumulation of free α-globin. Rather, systemic proteasome inhibition activated compensatory proteotoxic stress-response mechanisms, including autophagy, which cooperated with ubiquitin-mediated proteolysis to degrade free α-globin in erythroid cells. Our findings show that multiple interregulated PQC responses degrade excess α-globin. Therefore, β-thalassemia fits into the broader framework of protein-aggregation disorders that use PQC pathways as cell-protective mechanisms.
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Mollan TL, Khandros E, Weiss MJ, Olson JS. Kinetics of α-globin binding to α-hemoglobin stabilizing protein (AHSP) indicate preferential stabilization of hemichrome folding intermediate. J Biol Chem 2012; 287:11338-50. [PMID: 22298770 DOI: 10.1074/jbc.m111.313247] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human α-hemoglobin stabilizing protein (AHSP) is a conserved mammalian erythroid protein that facilitates the production of Hemoglobin A by stabilizing free α-globin. AHSP rapidly binds to ferrous α with association (k'(AHSP)) and dissociation (k(AHSP)) rate constants of ≈10 μm(-1) s(-1) and 0.2 s(-1), respectively, at pH 7.4 at 22 °C. A small slow phase was observed when AHSP binds to excess ferrous αCO. This slow phase appears to be due to cis to trans prolyl isomerization of the Asp(29)-Pro(30) peptide bond in wild-type AHSP because it was absent when αCO was mixed with P30A and P30W AHSP, which are fixed in the trans conformation. This slow phase was also absent when met(Fe(3+))-α reacted with wild-type AHSP, suggesting that met-α is capable of rapidly binding to either Pro(30) conformer. Both wild-type and Pro(30)-substituted AHSPs drive the formation of a met-α hemichrome conformation following binding to either met- or oxy(Fe(2+))-α. The dissociation rate of the met-α·AHSP complex (k(AHSP) ≈ 0.002 s(-1)) is ∼100-fold slower than that for ferrous α·AHSP complexes, resulting in a much higher affinity of AHSP for met-α. Thus, in vivo, AHSP acts as a molecular chaperone by rapidly binding and stabilizing met-α hemichrome folding intermediates. The low rate of met-α dissociation also allows AHSP to have a quality control function by kinetically trapping ferric α and preventing its incorporation into less stable mixed valence Hemoglobin A tetramers. Reduction of AHSP-bound met-α allows more rapid release to β subunits to form stable fully, reduced hemoglobin dimers and tetramers.
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Affiliation(s)
- Todd L Mollan
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251, USA
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Khandros E, Mollan TL, Yu X, Wang X, Yao Y, D'Souza J, Gell DA, Olson JS, Weiss MJ. Insights into hemoglobin assembly through in vivo mutagenesis of α-hemoglobin stabilizing protein. J Biol Chem 2012; 287:11325-37. [PMID: 22287545 DOI: 10.1074/jbc.m111.313205] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
α-Hemoglobin stabilizing protein (AHSP) is believed to facilitate adult Hemoglobin A assembly and protect against toxic free α-globin subunits. Recombinant AHSP binds multiple forms of free α-globin to stabilize their structures and inhibit precipitation. However, AHSP also stimulates autooxidation of αO(2) subunit and its rapid conversion to a partially unfolded bishistidyl hemichrome structure. To investigate these biochemical properties, we altered the evolutionarily conserved AHSP proline 30 in recombinantly expressed proteins and introduced identical mutations into the endogenous murine Ahsp gene. In vitro, the P30W AHSP variant bound oxygenated α chains with 30-fold increased affinity. Both P30W and P30A mutant proteins also caused decreased rates of αO(2) autooxidation as compared with wild-type AHSP. Despite these abnormalities, mice harboring P30A or P30W Ahsp mutations exhibited no detectable defects in erythropoiesis at steady state or during induced stresses. Further biochemical studies revealed that the AHSP P30A and P30W substitutions had minimal effects on AHSP interactions with ferric α subunits. Together, our findings indicate that the ability of AHSP to stabilize nascent α chain folding intermediates prior to hemin reduction and incorporation into adult Hemoglobin A is physiologically more important than AHSP interactions with ferrous αO(2) subunits.
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Affiliation(s)
- Eugene Khandros
- Cell and Molecular Biology Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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α-Haemoglobin stabilising protein expression is influenced by mean cell haemoglobin and HbF levels in HbE/β-thalassaemia individuals. Blood Cells Mol Dis 2012; 48:17-21. [DOI: 10.1016/j.bcmd.2011.10.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 09/27/2011] [Accepted: 09/29/2011] [Indexed: 11/21/2022]
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Abstract
The specific self-association of proteins to form homodimers and higher order oligomers is an extremely common event in biological systems. In this chapter we review the prevalence of protein oligomerization and discuss the likely origins of this phenomenon. We also outline many of the functional advantages conferred by the dimerization or oligomerization of a wide range of different proteins and in a variety of biological roles, that are likely to have placed a selective pressure on biological systems to evolve and maintain homodimerization/oligomerization interfaces.
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Transcriptomic profiles of peripheral white blood cells in type II diabetes and racial differences in expression profiles. BMC Genomics 2011; 12 Suppl 5:S12. [PMID: 22369568 PMCID: PMC3287494 DOI: 10.1186/1471-2164-12-s5-s12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Background Along with obesity, physical inactivity, and family history of metabolic disorders, African American ethnicity is a risk factor for type 2 diabetes (T2D) in the United States. However, little is known about the differences in gene expression and transcriptomic profiles of blood in T2D between African Americans (AA) and Caucasians (CAU), and microarray analysis of peripheral white blood cells (WBCs) from these two ethnic groups will facilitate our understanding of the underlying molecular mechanism in T2D and identify genetic biomarkers responsible for the disparities. Results A whole human genome oligomicroarray of peripheral WBCs was performed on 144 samples obtained from 84 patients with T2D (44 AA and 40 CAU) and 60 healthy controls (28 AA and 32 CAU). The results showed that 30 genes had significant difference in expression between patients and controls (a fold change of <-1.4 or >1.4 with a P value <0.05). These known genes were mainly clustered in three functional categories: immune responses, lipid metabolism, and organismal injury/abnormaly. Transcriptomic analysis also showed that 574 genes were differentially expressed in AA diseased versus AA control, compared to 200 genes in CAU subjects. Pathway study revealed that "Communication between innate and adaptive immune cells"/"Primary immunodeficiency signaling" are significantly down-regulated in AA patients and "Interferon signaling"/"Complement System" are significantly down-regulated in CAU patients. Conclusions These newly identified genetic markers in WBCs provide valuable information about the pathophysiology of T2D and can be used for diagnosis and pharmaceutical drug design. Our results also found that AA and CAU patients with T2D express genes and pathways differently.
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Wajcman H, Vasseur C, Pissard S, Baudin-Creuza V. α-Hemoglobin Stabilizing Protein: A Modulating Factor in Thalassemias? Hemoglobin 2011; 35:463-8. [DOI: 10.3109/03630269.2011.576354] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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