Selenium Deficiency in a Mouse Model of Sickle Cell Disease Resulted in Increased Oxygen Consumption and Aberrant Mitochondrial Retention (OR11-05-19)

Abstract Objectives Sickle Cell Disease (SCD) is caused by a single point mutation in the β-globin gene, resulting in the polymerization of the altered hemoglobin βS in hypoxic conditions, affecting millions of people worldwide. Previous studies have shown that there are lower selenium levels and reduced activity of the antioxidant selenoprotein GPX1 in SCD patients. The objective of this study was to investigate the consequences of selenium deficiency in a SCD mouse model. Methods Humanized SCD (HbSS) mice (Townes model) and wild type (HbAA) mice were purchased from Jackson Laboratories (Bar Harbor, ME). Mice were fed either a selenium-deficient (<0.01 mg/kg) or a selenium adequate (0.1 mg/kg) diet for 4 weeks. Hematological testing was performed using the ADVIATM 120 analyzer (Bayer Corporation, NY). Mitochondrial retention and reactive oxygen species (ROS) were measured by flow cytometry with a BD LSRFortessaTM analyzer using Kaluza analysis software (Beckman Coulter, CA). The oxygen consumption rate (OCR) was measured from isolated red blood cells (RBCs) in real time using the Seahorse Extracellular Analyzer (Agilent, CA). Results RBCs normally eject their mitochondria before reaching maturity. However, a previous study demonstrated that there was increased RBC mitochondrial retention in SCD mice and patients when compared to controls. Feeding SCD mice a selenium deficient diet resulted in increased retention of mitochondria in RBCs (26% + 6.9%, 5% + 3.5%, n = 3, P < 0.01), decreased hemoglobin levels (5.7 + 0.17 g/dl, 7.0 + 0.83 g/dl, n = 3, P < 0.05), and an increased OCR of the RBCs (P < 0.01) in these animals when compared to SCD mice fed a selenium adequate diet. Conclusions Providing humanized SCD mice a selenium deficient diet resulted in increased mitochondrial retention in mature RBCs, decrease hemoglobin levels, and increased RBC oxygen consumption. RBC retention of mitochondria is associated with increased ROS and hemolysis, potentially contributing to the pain and vaso-occlusive crises that occur in the disease. These studies indicate that selenium deficiency may contribute to the severity of symptoms experienced by patients with SCD. Funding Sources This work is supported by a grant from the NIH.

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Beyond the Definitions of the Phenotypic Complications of Sickle Cell Disease: An Update on Management

The Scientific World JOURNAL ◽

10.1100/2012/949535 ◽

2012 ◽

Vol 2012 ◽

pp. 1-55 ◽

Cited By ~ 73

Author(s):

Samir K. Ballas ◽

Muge R. Kesen ◽

Morton F. Goldberg ◽

Gerard A. Lutty ◽

Carlton Dampier ◽

...

Keyword(s):

Sickle Cell Disease ◽

Point Mutation ◽

Sickle Cell ◽

Globin Gene ◽

Single Point ◽

Acute Chest Syndrome ◽

Single Point Mutation ◽

Cell Disease ◽

Exon 1 ◽

Abnormal Hemoglobin

The sickle hemoglobin is an abnormal hemoglobin due to point mutation (GAG → GTG) in exon 1 of theβglobin gene resulting in the substitution of glutamic acid by valine at position 6 of theβglobin polypeptide chain. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of sickle cell disease in general and sickle cell anemia in particular. The disease itself is chronic in nature but many of its complications are acute such as the recurrent acute painful crises (its hallmark), acute chest syndrome, and priapism. These complications vary considerably among patients, in the same patient with time, among countries and with age and sex. To date, there is no well-established consensus among providers on the management of the complications of sickle cell disease due in part to lack of evidence and in part to differences in the experience of providers. It is the aim of this paper to review available current approaches to manage the major complications of sickle cell disease. We hope that this will establish another preliminary forum among providers that may eventually lead the way to better outcomes.

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Sickle Cell Anemia: A review on the most severe form of Sickle Cell Disease

Bionatura ◽

10.21931/rb/cs/2019.02.01.19 ◽

2019 ◽

Vol 02 (Bionatura Conference Serie) ◽

Author(s):

María Belén Paredes ◽

María Eugenia Sulen

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Globin Gene ◽

Single Point ◽

Clinical Manifestations ◽

Severe Form ◽

Single Point Mutation ◽

Cell Disease ◽

Hemoglobin S

Sickle cell disease (SCD) is a group of hereditary disorders caused by a single point mutation in the β-globin gene. This mutation results in the formation of a mutated hemoglobin S (HbS) and the consequent sickle phenotype of erythrocytes. SCD is common in regions of malaria endemicity. However, changes in population dynamics enabled the movement of the mutated gene to other areas such as North America and Europe. Sickle cell anemia (SCA) is the most severe form of SCD and affects millions of people around the globe. The clinical manifestations of SCA arise primarily from the polymerization of deoxygenated hemoglobin S (deoxyHbS) leading to vascular occlusion and hemolytic anemia. Clinical complications of the disease are derived from deoxyHbS polymerization, but there are several therapeutic strategies to reduce the severity of the symptoms. Gene therapy has arisen as a new therapeutic approach aimed to cure rather than to treat the symptomatology of SCA by targeting the altered β-globin gene for gene correction.

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Development of β-globin gene correction in human hematopoietic stem cells as a potential durable treatment for sickle cell disease

Science Translational Medicine ◽

10.1126/scitranslmed.abf2444 ◽

2021 ◽

Vol 13 (598) ◽

pp. eabf2444

Author(s):

Annalisa Lattanzi ◽

Joab Camarena ◽

Premanjali Lahiri ◽

Helen Segal ◽

Waracharee Srifa ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Drug Product ◽

Globin Gene ◽

Monogenic Disease ◽

Single Point Mutation ◽

Cell Disease ◽

Gene Correction ◽

Hematopoietic Stem ◽

Virus Serotype

Sickle cell disease (SCD) is the most common serious monogenic disease with 300,000 births annually worldwide. SCD is an autosomal recessive disease resulting from a single point mutation in codon six of the β-globin gene (HBB). Ex vivo β-globin gene correction in autologous patient-derived hematopoietic stem and progenitor cells (HSPCs) may potentially provide a curative treatment for SCD. We previously developed a CRISPR-Cas9 gene targeting strategy that uses high-fidelity Cas9 precomplexed with chemically modified guide RNAs to induce recombinant adeno-associated virus serotype 6 (rAAV6)–mediated HBB gene correction of the SCD-causing mutation in HSPCs. Here, we demonstrate the preclinical feasibility, efficacy, and toxicology of HBB gene correction in plerixafor-mobilized CD34+ cells from healthy and SCD patient donors (gcHBB-SCD). We achieved up to 60% HBB allelic correction in clinical-scale gcHBB-SCD manufacturing. After transplant into immunodeficient NSG mice, 20% gene correction was achieved with multilineage engraftment. The long-term safety, tumorigenicity, and toxicology study demonstrated no evidence of abnormal hematopoiesis, genotoxicity, or tumorigenicity from the engrafted gcHBB-SCD drug product. Together, these preclinical data support the safety, efficacy, and reproducibility of this gene correction strategy for initiation of a phase 1/2 clinical trial in patients with SCD.

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Cardiovascular complications in patients with sickle cell disease

Hematology ◽

10.1182/asheducation-2017.1.423 ◽

2017 ◽

Vol 2017 (1) ◽

pp. 423-430 ◽

Cited By ~ 10

Author(s):

Mark T. Gladwin

Keyword(s):

Sickle Cell Disease ◽

Hemolytic Anemia ◽

Sickle Cell ◽

Single Point ◽

Systolic Pressure ◽

Cardiovascular Complications ◽

Left Ventricular ◽

Pulmonary Artery Systolic Pressure ◽

Single Point Mutation ◽

Cell Disease

Abstract Sickle cell disease (SCD) is an autosomal recessive disease in which homozygosity for a single point mutation in the gene encoding the β-globin chain produces hemoglobin S molecules that polymerize within the erythrocyte during deoxygenation; the result is sustained hemolytic anemia and vaso-occlusive events. As patients live to adulthood, the chronic impact of sustained hemolytic anemia and episodic vaso-occlusive episodes leads to progressive end-organ complications. This scenario culminates in the development of 1 or more major cardiovascular complications of SCD for which there are no approved or consensus therapies. These complications include elevated pulmonary artery systolic pressure, pulmonary hypertension, left ventricular diastolic heart disease, dysrhythmia, sudden death, and chronic kidney disease with associated proteinuria, microalbuminuria, and hemoglobinuria. In patients with advancing age, cardiopulmonary organ dysfunction and chronic kidney injury have significant effects on morbidity and premature mortality. Over the last 15 years, a number of tests have been validated in multiple replicate cohort studies that identify patients with SCD at the highest risk of experiencing pulmonary and systemic vasculopathy and death, providing for screening strategies tied to targeted, more aggressive diagnostic and therapeutic interventions.

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Delta‐globin gene expression improves sickle cell disease in a humanised mouse model

British Journal of Haematology ◽

10.1111/bjh.17561 ◽

2021 ◽

Author(s):

Susanna Porcu ◽

Michela Simbula ◽

Maria F. Marongiu ◽

Andrea Perra ◽

Daniela Poddie ◽

...

Keyword(s):

Gene Expression ◽

Sickle Cell Disease ◽

Mouse Model ◽

Sickle Cell ◽

Globin Gene ◽

Cell Disease ◽

Globin Gene Expression

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NRF2 mediates γ-globin gene regulation through epigenetic modifications in a β-YAC transgenic mouse model

Experimental Biology and Medicine ◽

10.1177/1535370220945305 ◽

2020 ◽

Vol 245 (15) ◽

pp. 1308-1318

Author(s):

Xingguo Zhu ◽

Caixia Xi ◽

Alexander Ward ◽

Mayuko Takezaki ◽

Huidong Shi ◽

...

Keyword(s):

Sickle Cell Disease ◽

Mouse Model ◽

Sickle Cell ◽

Globin Gene ◽

Fetal Hemoglobin ◽

Dimethyl Fumarate ◽

Cell Disease ◽

Nrf2 Activator ◽

Globin Gene Regulation ◽

Globin Gene Expression

NRF2 is the master regulator for the cellular oxidative stress response and regulates γ-globin gene expression in human erythroid progenitors and sickle cell disease mice. To explore NRF2 function, we established a human β-globin locus yeast artificial chromosome transgenic/NRF2 knockout (β-YAC/NRF2−/−) mouse model. NRF2 loss reduced γ-globin gene expression during erythropoiesis and abolished the ability of dimethyl fumarate, an NRF2 activator, to enhance γ-globin transcription. We observed decreased H3K4Me1 and H3K4Me3 chromatin marks and association of TATA-binding protein and RNA polymerase II at the β-locus control region (LCR) and γ-globin gene promoters in β-YAC/NRF2−/− mice. As a result, long-range chromatin interaction between the LCR DNase I hypersensitive sites and γ-globin gene was decreased, while interaction with the β-globin was not affected. Further, NRF2 loss silenced the expression of DNA methylcytosine dioxygenases TET1, TET2, and TET3 and inhibited γ-globin gene DNA hydroxymethylation. Subsequently, protein-protein interaction between NRF2 and TET3 was demonstrated. These data support the ability of NRF2 to mediate γ-globin gene regulation through epigenetic DNA and histone modifications. Impact statement Sickle cell disease is an inherited hemoglobin disorder that affects over 100,000 people in the United States causing high morbidity and early mortality. Although new treatments were recently approved by the FDA, only one drug Hydroxyurea induces fetal hemoglobin expression to inhibit sickle hemoglobin polymerization in red blood cells. Our laboratory previously demonstrated the ability of the NRF2 activator, dimethyl fumarate to induce fetal hemoglobin in the sickle cell mouse model. In this study, we investigated molecular mechanisms of γ-globin gene activation by NRF2. We observed the ability of NRF2 to modulate chromatin structure in the human β-like globin gene locus of β-YAC transgenic mice during development. Furthermore, an NRF2/TET3 interaction regulates γ-globin gene DNA methylation. These findings provide potential new molecular targets for small molecule drug developed for treating sickle cell disease.

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Neutrophil-Platelet Micro-Emboli Enable Vaso-Occlusion in Sickle Cell Disease

Blood ◽

10.1182/blood.v124.21.2695.2695 ◽

2014 ◽

Vol 124 (21) ◽

pp. 2695-2695

Author(s):

Prithu Sundd ◽

Maritza Jimenez ◽

Enrico M Novelli ◽

Mark T Gladwin

Keyword(s):

Endothelial Cells ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Globin Gene ◽

Cellular Adhesion ◽

Epifluorescence Microscopy ◽

Single Point Mutation ◽

Cellular Interactions ◽

Cell Disease ◽

Cellular Adhesion Molecule

Abstract Introduction: Sickle Cell Disease (SCD) is an autosomal-recessive-hemolytic disorder caused by a single point mutation in the β-globin gene that leads to sickling of RBCs under deoxygenated condition. Sickle RBCs (sRBCs) are not only rigid but also express adhesion molecules, which are not normally expressed on RBCs. The sticky and rigid sRBCs are believed to get trapped in blood vessels along with leukocytes to cause vaso-occlusion, which is the predominant pathophysiology underlying acute pain crisis in SCD patients. The process of sickling and vaso-occlusion leads to sRBC hemolysis, which releases hemoglobin, ADP and other RBC contents into the blood giving rise to a pro-inflammatory and pro-coagulant state, characterized by activated leukocytes, platelets, endothelial cells (ECs), tissue factor (TF) and enhanced adhesion of these cells to each other. Leukocyte–endothelium adhesion starts with leukocyte rolling mediated by P-selectin-glycoprotein-ligand (PSGL)-1 on leukocytes binding to P-selectin on endothelium. Rolling is followed by firm arrest, which is mediated by activated β2-integrins (LFA-1 and Mac-1) on the leukocytes binding to inter-cellular-adhesion-molecule (ICAM)-1 on endothelium. Although neutrophils have been shown to play a role in the onset of vaso-occlusion by interacting with sRBCs and platelets in cremaster venules of SCD mice; the cellular, molecular and biophysical mechanisms that enable vaso-occlusion in SCD patients are not known. Materials and Methods: Freshly collected heparinized blood from SCD patients and race matched control subjects was perfused through a polydimethylsiloxane (PDMS) based microfluidic flow chamber with a glass bottom coated with either human micro-vascular endothelial cells or a cocktail of recombinant human P-selection, ICAM-1 and IL-8 at a venular/arteriolar wall shear stress. Fluorochrome conjugated Abs against CD16, CD235a and CD49b were added to the blood to stain neutrophils, sRBCs and platelets, respectively, and cellular interactions were recorded using multi-color Quantitative Dynamic Footprinting (qDF; Sundd et al Nature Methods 2010) or epifluorescence microscopy. Specificity of cellular interactions was tested using function blocking Abs against human Mac-1, LFA-1, P-selectin and PSGL-1. Results: SCD patients had much higher number of circulating neutrophils than control patients. Neutrophils rolled, arrested and then captured free flowing platelets in both SCD and control blood. However, significantly larger number of neutrophils rolled and arrested in SCD blood than control blood. As a result, much higher number of platelets was captured by arrested neutrophils in SCD blood than control blood, which led to the formation of neutrophil-platelet micro-emboli. The micro-emboli formation was mediated by a unique biophysical mechanism, which involved PSGL-1 and Mac-1 on neutrophils binding to P-selectin and GPIbα on platelets, respectively. Conclusion: Vaso-occlusion involves a cascade of adhesive events. First, neutrophils roll and arrest at the site of vaso-occlusion. Second, arrested neutrophils capture free flowing platelets and RBCs to form micro-emboli. Third, eventually these micro-emboli give rise to micro-thrombi, which cause stasis of blood flow. Acknowledgments: This study is supported by 11SDG7340005 from the American Heart Association (P.S.), VMI start-up funds (P.S.) and CBTP-T32 fellowship HL076124 (M.J). Disclosures No relevant conflicts of interest to declare.

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BIBLIOMETRIC ANALYSIS OF GLOBAL SICKLE CELL DISEASE RESEARCH FROM 1997 – 2017

10.21203/rs.2.10361/v1 ◽

2019 ◽

Author(s):

Henshaw Okoroiwu ◽

Francisco López-Muñoz ◽

F. Javier Povedano-Montero

Keyword(s):

United States ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Scientific Literature ◽

Single Point ◽

World Health ◽

Single Point Mutation ◽

Cell Disease ◽

Growth Trend ◽

Disease Research

Abstract Background: Sickle cell disease (SCD) is an autosomal recessive genetic disease caused by single point mutation in the β-globin chain of the hemoglobin. It has been recognized by World Health Organization as a public health priority since 2006. Methods: Scopus database was used in this study with the search descriptors: “sickle cell” and “sickle cell disease”. We applied common bibliometric indicators to evaluate the trend in scientific literature in sickle cell disease research. Results: We retrieved a total of 19,921 scientific literatures in the repertoire from 1997 to 2017. Price law was fulfilled in the trend of production of scientific literature in SCD as the growth of scientific literature was more exponential (r = 0.959) than linear (r = 0.9449). We observed a duplication time of 4.55 years. The Bradford core was made up of 69 journals with Blood at the top, publishing the most number of articles. The most productive institutions were mostly United States agencies and hospitals. United States was the most productive country. National Institute of Health was the most productive institution and also had the highest number of citation. Vichinsky E was the most productive author while the most cited article was published by Circulation. Conclusion: The growth of scientific literature in SCD was found to be high. However, the exponential growth trend shows a “yet-to-be-explored” area of research. This study will be useful for physicians, researchers, research funders, policy cum decision makers.

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Effects of vaccines in patients with sickle cell disease: a systematic review protocol

BMJ Open ◽

10.1136/bmjopen-2017-021140 ◽

2018 ◽

Vol 8 (3) ◽

pp. e021140

Author(s):

Alison Beriliy Wiyeh ◽

Leila Hussein Abdullahi ◽

Ambroise Wonkam ◽

Charles Shey Wiysonge ◽

Mamadou Kaba

Keyword(s):

Systematic Review ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Single Point ◽

Ethical Review ◽

Advisory Group ◽

Single Point Mutation ◽

Common Disease ◽

Cell Disease ◽

Increased Risk

IntroductionSickle cell disease (SCD) is an inherited haematological disorder caused by a single point mutation (Glub6Val) that promotes polymerisation of haemoglobin S and sickling of erythrocytes. Inflammation, haemolysis, microvascular obstruction and organ damage characterise the highly variable clinical expression of SCD. People with SCD are at increased risk of severe infections, hence the need for vaccination against common disease-causing organisms in this population. We aim to review the evidence on the efficacy and safety of vaccines in people with SCD.Methods and analysisThe present systematic review will examine the current data as indexed in PubMed, CENTRAL, EMBASE and EBSCOHost. We will consult Strategic Advisory Group of Experts practice statements, conference abstracts, reference lists of relevant articles, WHO ICTRP trial registry and experts in the field. Two authors will independently screen search outputs, select studies, extract data and assess risk of bias; resolving discrepancies by discussion and consensus between the two authors or arbitration by a third author when necessary. We will perform a meta-analysis for clinically homogenous studies. Evidence from clinically diverse studies will be aggregated using narrative synthesis of the findings. In either case, we will use the GRADE approach to assess the strength of the available evidence.Ethics and disseminationThe study draws on data that are readily available in the public domain, hence no formal ethical review and approval is required. The findings of this review will be disseminated through conference presentations and a publication in a peer-reviewed journal.PROSPERO registration numberCRD42018084051.

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