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1.
Bioorg Chem ; 140: 106768, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37586133

RESUMO

Pharmacological induction of fetal hemoglobin has proven to be a promising therapeutic intervention in ß-hemoglobinopathies by reducing the globin chain imbalance and inhibiting sickle cell polymerization. Fagonia indica has shown therapeutic relevance to ß-thalassemia. Therefore, we study the ethnopharmacological potential of Fagonia indica and its biomarker compounds for their HbF induction ability for the treatment of ß-thalassemia. Here, we identify, compound 8 (triterpenoid glycosides) of F. indica. as a prominent HbF inducer in-vitro and in-vivo. Compound 8 showed potent erythroid differentiation, enhanced cellular proliferation, ample accumulation of total hemoglobin, and a strong notion of γ-globin gene expression in K562 cultures. Compound 8 treatment also revealed strong induction of erythroid differentiation and fetal hemoglobin mRNA and protein in adult erythroid precursor cells. This induction was associated with simultaneous downregulation of BCL11A and SOX6, and overexpression of the GATA-1 gene, suggesting a compound 8-mediated partial mechanism involved in the reactivation of fetal-like globin genes. The in vivo study with compound 8 (10 mg/kg) in ß-YAC mice resulted in significant HbF synthesis demonstrated by the enhanced level of F-cells (84.14 %) and an 8.85-fold increase in the γ-globin gene. Overall, the study identifies compound 8 as a new HbF-inducing entity and provides an early "proof-of-concept" to enable the initiation of preclinical and clinical studies in the development of this HbF-inducing agent for ß-thalassemia.


Assuntos
Hemoglobinopatias , Triterpenos , Talassemia beta , Humanos , Animais , Camundongos , gama-Globinas/genética , gama-Globinas/metabolismo , Talassemia beta/tratamento farmacológico , Talassemia beta/genética , Talassemia beta/metabolismo , Glicosídeos/farmacologia , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Células K562 , Fatores de Transcrição , Expressão Gênica , Proteínas Repressoras
2.
Genes Cells ; 28(3): 211-225, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36565308

RESUMO

Macrophages play essential roles in erythrophagocytosis and iron recycling. ß-thalassemia is characterized by a genetic defect in hemoglobin synthesis, which increases the rate of iron recycling. We previously showed that reduced expression of the BTB and CNC homolog 1 (BACH1) gene leads to increased phagocytosis of abnormal RBCs by activated monocytes. However, the mechanisms underlying this abnormal RBC clearance remained unclear. Herein, the spleen and bone marrow cells of ß-thalassemic mice were examined for erythrophagocytosis CD markers and iron-recycling genes. Higher expression levels of CD47 and CD163 on RBCs and macrophages, respectively, were observed in ß-thalassemic mice than in wild-type cells. The decreased expression of BACH1 caused an increase in Nrf2, Spic, Slc40a1, and HMOX1 expression in splenic red pulp macrophages of thalassemic mice. To investigate BACH1 regulation, a macrophage cell line was transfected with BACH1-siRNA. Decreased BACH1 expression caused an increase in CD163 expression; however, the expression levels were lower when the cells were cultured in media supplemented with ß-thalassemia/HbE patient plasma. Additionally, the iron recycling-related genes SPIC, SLC40A1, and HMOX1 were significantly upregulated in BACH1-suppressed macrophages. Our findings provide insights into BACH1 regulation, which plays an important role in erythrophagocytosis and iron recycling in thalassemic macrophages.


Assuntos
Ferro , Talassemia beta , Camundongos , Animais , Ferro/metabolismo , Talassemia beta/genética , Talassemia beta/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Eritrócitos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética
3.
Clin Lab ; 68(3)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35254032

RESUMO

BACKGROUND: ß-thalassemia is an inherited disorder that stems from a defect in beta-globin chain synthesis. Iron overload toxicity is one of the major clinical complications in ß-thalassemia that may be due to a reduction in the hepcidin level. As a result, intestinal iron absorption increases and finally iron overload occurs. The current study aimed to investigate the effect of curcumin on serum iron status, ferritin, and transferrin in patients with ß-thalas-semia intermedia. METHODS: This study was a randomized, controlled, double-blind clinical trial. Before and after the intervention period with curcumin, 5 ml blood was taken for the measurement of the entire index related to iron status. RESULTS: Our results demonstrated the levels of serum iron (p-value < 0.001), ferritin (p-value = 0.002), and transferrin saturation (p-value < 0.001) significantly decreased in the curcumin group compared to placebo. CONCLUSIONS: The data presented in this article show that curcumin supplementation would be effective in alleviating iron overload in patients with ß-thalassemia intermedia.


Assuntos
Curcumina , Sobrecarga de Ferro , Talassemia beta , Curcumina/uso terapêutico , Método Duplo-Cego , Ferritinas/metabolismo , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Talassemia beta/metabolismo
4.
Am J Hematol ; 96(11): 1518-1531, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34347889

RESUMO

The treatment landscape for patients with ß-thalassemia is witnessing a swift evolution, yet several unmet needs continue to persist. Patients with transfusion-dependent ß-thalassemia (TDT) primarily rely on regular transfusion and iron chelation therapy, which can be associated with considerable treatment burden and cost. Patients with non-transfusion-dependent ß-thalassemia (NTDT) are also at risk of significant morbidity due to the underlying anemia and iron overload, but treatment options in this patient subgroup are limited. In this review, we provide updates on clinical trials of novel therapies targeting the underlying pathology in ß-thalassemia, including the α/non-α-globin chain imbalance, ineffective erythropoiesis, and iron dysregulation.


Assuntos
Talassemia beta/terapia , Transfusão de Sangue , Ensaios Clínicos como Assunto , Descoberta de Drogas , Eritropoese/efeitos dos fármacos , Humanos , Ferro/metabolismo , Quelantes de Ferro/uso terapêutico , alfa-Globinas/genética , alfa-Globinas/metabolismo , Talassemia beta/genética , Talassemia beta/metabolismo , Talassemia beta/patologia
5.
Int J Mol Sci ; 21(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233561

RESUMO

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.


Assuntos
Desferroxamina/administração & dosagem , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Reação Transfusional/complicações , Talassemia beta/terapia , Adulto , Transfusão de Sangue , Cardiomiopatias/sangue , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/prevenção & controle , Terapia por Quelação/efeitos adversos , Terapia por Quelação/métodos , Desferroxamina/efeitos adversos , Monitoramento de Medicamentos/instrumentação , Monitoramento de Medicamentos/métodos , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Ferro/toxicidade , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Transferrina/metabolismo , Reação Transfusional/sangue , Reação Transfusional/fisiopatologia , Talassemia beta/metabolismo , Talassemia beta/patologia
6.
Diabetes Care ; 43(11): 2830-2839, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32887708

RESUMO

OBJECTIVE: We systematically explored the link of pancreatic iron with glucose metabolism and with cardiac complications in a cohort of 1,079 patients with thalassemia major (TM) enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. RESEARCH DESIGN AND METHODS: MRI was used to quantify iron overload (T2* technique) and cardiac function (cine images) and to detect macroscopic myocardial fibrosis (late gadolinium enhancement technique). Glucose metabolism was assessed by the oral glucose tolerance test (OGTT). RESULTS: Patients with normal glucose metabolism showed significantly higher global pancreas T2* values than patients with impaired fasting glucose, impaired glucose tolerance, and diabetes. A pancreas T2* <13.07 ms predicted an abnormal OGTT. A normal pancreas T2* value showed a 100% negative predictive value for disturbances of glucose metabolism and for cardiac iron. Patients with myocardial fibrosis showed significantly lower pancreas T2* values. Patients with cardiac complications had significantly lower pancreas T2* values. No patient with arrhythmias/heart failure had a normal global pancreas T2*. CONCLUSIONS: Pancreatic iron is a powerful predictor not only for glucose metabolism but also for cardiac iron and complications, supporting the close link between pancreatic iron and heart disease and the need to intensify iron chelation therapy to prevent both alterations of glucose metabolism and cardiac iron accumulation.


Assuntos
Glucose/metabolismo , Cardiopatias/complicações , Cardiopatias/metabolismo , Sobrecarga de Ferro/metabolismo , Ferro/metabolismo , Pâncreas/metabolismo , Talassemia beta/complicações , Talassemia beta/metabolismo , Adolescente , Adulto , Idoso , Criança , Meios de Contraste/metabolismo , Diabetes Mellitus/metabolismo , Feminino , Fibrose , Gadolínio/metabolismo , Intolerância à Glucose/complicações , Teste de Tolerância a Glucose , Cardiopatias/diagnóstico por imagem , Humanos , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Estudos Prospectivos , Adulto Jovem
7.
J Clin Invest ; 130(1): 491-506, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31638596

RESUMO

ß-Thalassemia is a genetic anemia caused by partial or complete loss of ß-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 ß-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 ß-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 ß-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 ß-thalassemia.


Assuntos
Proteínas de Transporte de Cátions/antagonistas & inibidores , Compostos Férricos/administração & dosagem , Maltose/análogos & derivados , Talassemia beta/tratamento farmacológico , Administração Oral , Animais , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Cães , Avaliação Pré-Clínica de Medicamentos , Eritropoese/efeitos dos fármacos , Eritropoese/genética , Feminino , Hepcidinas/metabolismo , Humanos , Ferro/sangue , Ferro/metabolismo , Células Madin Darby de Rim Canino , Masculino , Maltose/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Proteólise/efeitos dos fármacos , Ratos Sprague-Dawley , Ubiquitinação/efeitos dos fármacos , Globinas beta/deficiência , Globinas beta/genética , Talassemia beta/genética , Talassemia beta/metabolismo
8.
Complement Ther Med ; 46: 24-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31519283

RESUMO

OBJECTIVES: The aim of this study was to determine whether quercetin can reduce iron overload and inflammation in thalassemic patients. METHODS: Eighty four patients were recruited to this study and randomly assigned to two groups: 42 patients received a 500 mg/day quercetin tablet and 42 others took a 500 mg/day starch placebo for 12 weeks. Demographic, anthropometric and biochemical evaluation were performed. RESULTS: ANCOVA analysis revealed that compared to the control group, quercetin could reduce high sensitivity C-reactive protein (hs-CRP) (P = 0.046), iron (p = 0.036), ferritin (p = 0.043), and transferrin saturation (TS) (p = 0.008) and increase transferrin (p = 0.045) significantly, but it had no significant effect on total iron binding capacity (TIBC) (p = 0.734) and tumor necrosis factor α (TNF-α) (p = 0.310). CONCLUSIONS: Quercetin could ameliorate the iron status in thalassemia major, but its effect on inflammation is indistinctive.


Assuntos
Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Sobrecarga de Ferro/tratamento farmacológico , Ferro/efeitos adversos , Ferro/uso terapêutico , Quercetina/uso terapêutico , Talassemia beta/tratamento farmacológico , Adulto , Proteína C-Reativa/metabolismo , Método Duplo-Cego , Feminino , Ferritinas/metabolismo , Humanos , Inflamação/metabolismo , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/metabolismo , Masculino , Transferrina/metabolismo , Talassemia beta/metabolismo
9.
Pancreas ; 48(5): 636-643, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31091209

RESUMO

OBJECTIVES: We have investigated the efficacy of mono- and combined therapy with green tea extract (GTE) in mobilizing redox iron, scavenging reactive oxygen species (ROS), and improving insulin production in iron-loaded pancreatic cells. METHODS: Rat insulinoma pancreatic ß-cells were iron-loaded using culture medium supplemented with either fetal bovine serum or ferric ammonium citrate and treated with various doses of GTE for epigallocatechin-3-gallate (EGCG) equivalence and in combination with iron chelators. Cellular iron, ROS, and secretory insulin were measured. RESULTS: The rat insulinoma pancreatic cells took up iron from fetal bovine serum more rapidly than ferric ammonium citrate. After treatment with GTE (0.23-2.29 µg EGCG equivalent), cellular levels of iron and ROS were dose dependently decreased. Importantly, secretory insulin levels were increased nearly 2.5-fold with 2.29 µg of EGCG equivalent GTE, indicating a recovery in insulin production. CONCLUSIONS: Green tea EGCG ameliorated oxidative damage of iron-loaded ß-cells by removing redox iron and free radicals and attenuating insulin production. The impact can result in the restoration of pancreatic functions and an increase in insulin production. Green tea extract exerts iron-chelating, free-radical scavenging, and pancreato-protective effects in the restoration of ß-cell functions, all of which we believe can increase insulin production in diabetic ß-thalassemia patients.


Assuntos
Catequina/análogos & derivados , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Ferro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Chá/química , Animais , Catequina/farmacologia , Linhagem Celular Tumoral , Complicações do Diabetes/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Ratos , Talassemia beta/complicações , Talassemia beta/metabolismo
10.
Ann Hematol ; 98(8): 1813-1826, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31098739

RESUMO

Pregnant patients with ß-thalassemia are more likely to have progressive anemia which expose them to risk of adverse pregnancy outcomes, blood transfusion, and iron overload. Results from our previous study indicated that Colla corii asini (CCA, E'jiao), a natural ingredient of traditional Chinese medicine, could significantly increase hemoglobin level of pregnant women with ß- thalassemia, but the underlying molecular mechanism was unclear. Thus, we applied high-throughput transcriptome sequencing to study the transcriptomic change before and after the CCA treatment. Twenty eligible pregnant women were recruited and randomized to either the CCA treatment group or the blank control group in a 3:1 ratio. Patients in the treatment group orally received daily 15 g CCA powder for 4 weeks. We analyzed the therapeutic effect indexes and the transcriptomic change in subjects' peripheral blood before and after treatment. We found that ß CD 41-42(-TTCT)/ßA was the main genotype of the subjects. The regulatory impact of CCA treatment became more evident among the subjects of genotype ß CD 41-42(-TTCT)/ßA. Gene ontogenesis analysis revealed that the top five molecular functions of differentially expressed genes were involved in membrane functionality and cellular structure. We further identified two consistent upregulated genes ZNF471 and THOC5 in the effective treatment group, which were engaged in Kruppel-associated box (KRAB) domain-containing zinc-finger protein pathway and THOC5 pathway, respectively. Based on our current findings, we hypothesize that the anti-anemia effect of CCA on pregnant women with ß-thalassemia might be related to translation regulation of spectrin synthesis, membrane stability, and eventually prolonged the life span of erythrocytes.


Assuntos
Gelatina/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Fármacos Hematológicos/uso terapêutico , Medicina Tradicional Chinesa/métodos , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Talassemia beta/tratamento farmacológico , Administração Oral , Adulto , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas Nucleares/agonistas , Proteínas Nucleares/metabolismo , Gravidez , Proteômica/métodos , Proteínas Repressoras/agonistas , Proteínas Repressoras/metabolismo , Transdução de Sinais , Espectrina/genética , Espectrina/metabolismo , Transcriptoma/efeitos dos fármacos , Talassemia beta/genética , Talassemia beta/metabolismo , Talassemia beta/patologia
11.
Biomed Res Int ; 2019: 6573497, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31119181

RESUMO

BACKGROUND: Endocrinopathies are common in patients with ß-thalassemia major despite parenteral iron chelation therapy with deferoxamine. Prevalence of abnormal glucose metabolism in previous studies was controversial. The aim of this study was to discuss the prevalence of abnormal glucose metabolism in ß-thalassemia major based on a meta-analysis. METHODS: PubMed, ScienceDirect, Springerlink, Ovid, Web of Science, MEDLINE, Wanfang database, and Chinese National Knowledge Internet were searched for relevant articles. Two authors selected the articles according to the inclusion criteria and then extracted the data. The prevalence of diabetes mellitus (DM) in ß-thalassemia major was defined as the primary outcome. The prevalence with the 95% confidence interval (95%CI) was used to evaluate the proportion of abnormal glucose metabolism and other endocrine disorders in patients with ß-thalassemia major. Subgroup analyses were applied to explore the prevalence in different regions. Sensitivity analysis and publication bias assessment were also conducted. RESULTS: A total of 44 studies with 16605 cases were included in this analysis. Diabetes mellitus was present in 6.54% (95% CI: 5.30%-7.78%). The fixed subgroup study revealed that the region with the highest prevalence was the Middle East (prevalence= 7.90%, 95% CI: 5.75%-10.05%). The accumulated meta-analysis revealed that the prevalence of DM in ß-thalassemia major was relatively steady in each year. The prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and other endocrine disorders in ß-thalassemia major was 17.21% (95% CI: 8.43%-26.00%), 12.46% (95% CI: 5.98%-18.94%), and 43.92% (95% CI: 37.94%-49.89%), respectively. Sensitivity analysis showed that the pooled results were robust; publication bias assessment revealed that there was no significant evidence that the pooled results were influenced by publication bias. CONCLUSION: High prevalence of endocrine disorders involving abnormal glucose metabolism was detected in ß-thalassemia major. Treatment and prevention measurements may be necessary to prevent growth and endocrine problems.


Assuntos
Diabetes Mellitus/epidemiologia , Doenças do Sistema Endócrino/epidemiologia , Glucose/metabolismo , Talassemia beta/epidemiologia , Terapia por Quelação , Desferroxamina/uso terapêutico , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Doenças do Sistema Endócrino/complicações , Doenças do Sistema Endócrino/metabolismo , Doenças do Sistema Endócrino/patologia , Intolerância à Glucose , Humanos , Quelantes de Ferro/uso terapêutico , Oriente Médio/epidemiologia , Talassemia beta/complicações , Talassemia beta/metabolismo , Talassemia beta/patologia
12.
Blood Transfus ; 17(3): 165-170, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30036179

RESUMO

BACKGROUND: Transfusion dependency determines iron overload in thalassaemia major, with devastating complications. Significant liver iron overload has been observed from early childhood and we aimed to evaluate factors that could predict liver iron overload at the first magnetic resonance imaging (MRI). MATERIALS AND METHODS: All transfusion-dependent children who underwent MRI to assess iron overload were retrospectively studied. Age, weight, height, blood requirement, chelation drug and dosage, serum ferritin and liver enzymes were evaluated at three specific steps: start of transfusion regimen, start of chelation therapy, and first MRI. RESULTS: Among 198 patients, 25 children met inclusion criteria. No differences were detected in all the assessed parameters at start of transfusion regimen and chelation therapy (p>0.05) between patients with good iron balance (liver iron concentration [LIC] <7 mg Fe/g dry weight [dw]) and liver iron overload (LIC >7). At the first MRI, patients with iron overload had significantly higher serum ferritin (3,080.3±1,078.5 vs 1,672.0±705.3 ng/mL; p<0.01) while patients with good iron control maintained a stable ferritin value from the start of chelation therapy but showed significantly lower height Z-score (-1.48±1.02 vs -0.36±1.55; p=0.04). Serum ferritin >1,770 ng/mL was detected as the best threshold for predicting liver iron overload at the first MRI (p=0.0003). CONCLUSION: In order to prevent liver iron overload at the first MRI, children should maintain a stable level of serum ferritin below 1,770 from the start of chelation therapy. However, strict monitoring of growth is mandatory.


Assuntos
Sobrecarga de Ferro , Ferro/metabolismo , Fígado , Imageamento por Ressonância Magnética , Talassemia beta , Terapia por Quelação , Pré-Escolar , Feminino , Humanos , Lactente , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Fígado/diagnóstico por imagem , Fígado/metabolismo , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Talassemia beta/diagnóstico por imagem , Talassemia beta/tratamento farmacológico , Talassemia beta/metabolismo
13.
Eur J Radiol ; 103: 65-70, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29803388

RESUMO

BACKGROUND: The reciprocal of multiecho gradient-echo (ME-GRE) T2* magnetic resonance imaging (MRI) R2*, rises linearly with tissue iron concentration in both heart and liver. Little is known about renal iron deposition in ß-thalassemia major (ß-TM). AIM: To assess renal iron overload by MRI and its relation to total body iron and renal function among 50 pediatric patients with ß-TM. METHODS: Serum ferritin, serum cystatin C, urinary albumin creatinine ratio (UACR), and urinary ß2-microglobulin (ß2 M) were measured with calculation of ß2 M/albumin ratio. Quantification of liver, heart and kidney iron overload was done by MRI. RESULTS: Serum cystatin C, UACR and urinary ß2 microglobulin as well as urinary ß2m/albumin were significantly higher in ß-TM patients than the control group. No significant difference was found as regards renal R2* between Patients with mean serum ferritin above 2500 µg/L and those with lower serum cutoff. Renal R2* was higher in patients with poor compliance to chelation therapy and positively correlated to indirect bilirubin, LDH, cystatin C and LIC but inversely correlated to cardiac T2*. CONCLUSION: kidney iron deposition impairs renal glomerular and tubular functions in pediatric patients with ß-TM and is related to hemolysis, total body iron overload and poor compliance to chelation.


Assuntos
Terapia por Quelação/métodos , Sobrecarga de Ferro/terapia , Fígado/diagnóstico por imagem , Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Talassemia beta/metabolismo , Biomarcadores/metabolismo , Criança , Estudos Transversais , Feminino , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/metabolismo , Masculino , Talassemia beta/diagnóstico por imagem
14.
Acta Biomed ; 89(2-S): 33-40, 2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29451227

RESUMO

Despite regular blood transfusion and iron chelation therapy, growth impairment and pubertal delay are commonly seen in children and adolescents with transfusion-dependent Beta thalassaemia major (BTM) and sickle cell disease (SCD). We evaluated growth parameters and endocrine disorders in relation to the liver iron concentration (LIC) assessed by the Ferriscan® method in a cohort of adults with SCD (n =40) and BTM (n = 52) receiving blood transfusions and iron chelation therapy since early childhood. Before transfusion, hemoglobin concentration had not been less than 9 g/dl in the past 12 years; subcutaneous daily desferrioxamine was administered for all of them since early childhood (2- 5 years of age). All patients were shifted to oral therapy with deferasirox iron chelation, 20 mg/daily for the past 5 years. BTM patients with higher LIC (> 15 mg Fe/g dry weight)  had significantly shorter stature, lower insulin-like growth factor-I SDS (IGF-I SDS), higher alanine transferase (ALT) and  serum ferritin concentrations compared to thalassemic patients with lower LIC.  Patients with SCD with LIC > 8 mg Fe/g dry weight had significantly shorter stature, lower IGF-I SDS and higher ALT compared to SCD patients with lower LIC.  Patients with BTM had significantly shorted final height (Ht-SDS) , IGF-I SDS and FT4 level compared to patients with SCD.  LIC and mean fasting blood glucose (FBG) were significantly higher in patients with BTM compared to those with SCD. The linear regression  analysis showed  a significant correlation between LIC and  serum ferritin level in SCD and BTM. LIC and serum ferritin level were also correlated significantly with IGF-I level in patients with BTM. LIC was correlated significantly with ALT in patients with BTM. In conclusion, the prevalence of endocrinopathies especially hypothyroidism, DM, and hypogonadism were significantly higher in BTM patients versus SCD patients and higher in patients with higher LIC versus those with lower LIC. These complications occurred less frequently, but still considerable, in chronically transfused patients with SCD.


Assuntos
Anemia Falciforme/complicações , Estatura , Doenças do Sistema Endócrino/epidemiologia , Ferro/metabolismo , Fígado/metabolismo , Talassemia beta/complicações , Adulto , Idoso , Anemia Falciforme/metabolismo , Estudos Transversais , Feminino , Humanos , Quelantes de Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prevalência , Talassemia beta/metabolismo
15.
Stem Cell Res Ther ; 9(1): 46, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29482624

RESUMO

BACKGROUND: Thalassemia is the most common genetic disease worldwide; those with severe disease require lifelong blood transfusion and iron chelation therapy. The definitive cure for thalassemia is allogeneic hematopoietic stem cell transplantation, which is limited due to lack of HLA-matched donors and the risk of post-transplant complications. Induced pluripotent stem cell (iPSC) technology offers prospects for autologous cell-based therapy which could avoid the immunological problems. We now report genetic correction of the beta hemoglobin (HBB) gene in iPSCs derived from a patient with a double heterozygote for hemoglobin E and ß-thalassemia (HbE/ß-thalassemia), the most common thalassemia syndrome in Thailand and Southeast Asia. METHODS: We used the CRISPR/Cas9 system to target the hemoglobin E mutation from one allele of the HBB gene by homology-directed repair with a single-stranded DNA oligonucleotide template. DNA sequences of the corrected iPSCs were validated by Sanger sequencing. The corrected clones were differentiated into hematopoietic progenitor and erythroid cells to confirm their multilineage differentiation potential and hemoglobin expression. RESULTS: The hemoglobin E mutation of HbE/ß-thalassemia iPSCs was seamlessly corrected by the CRISPR/Cas9 system. The corrected clones were differentiated into hematopoietic progenitor cells under feeder-free and OP9 coculture systems. These progenitor cells were further expanded in erythroid liquid culture system and developed into erythroid cells that expressed mature HBB gene and HBB protein. CONCLUSIONS: Our study provides a strategy to correct hemoglobin E mutation in one step and these corrected iPSCs can be differentiated into hematopoietic stem cells to be used for autologous transplantation in patients with HbE/ß-thalassemia in the future.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Hemoglobina E , Células-Tronco Pluripotentes Induzidas/metabolismo , Talassemia beta , Autoenxertos , Feminino , Hemoglobina E/genética , Hemoglobina E/metabolismo , Humanos , Masculino , Mutação , Transplante de Células-Tronco , Talassemia beta/genética , Talassemia beta/metabolismo , Talassemia beta/terapia
16.
Biomed Chromatogr ; 32(6): e4200, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29388244

RESUMO

ß-Thalassemia is one of the most common inherited disorders and is widely distributed throughout the world. Owing to severe deficiencies in red blood cell production, blood transfusion is required to correct anemia for normal growth and development but causes additional complications owing to iron overload. The aim of this study is to quantify the biometal dysregulations in ß-thalassemia patients as compared with healthy controls. A total of 17 elements were analyzed in serum samples of ß-thalassemia patients and healthy controls using ICP-MS followed by chemometric analyses. Out of these analyzed elements, 14 showed a significant difference between healthy and disease groups at p < 0.05 and fold change >3. A PLS-DA model revealed an excellent separation with 89.8% sensitivity and 97.2% specificity and the overall accuracy of the model was 92.2%. This metallomic study revealed that there is major difference in metallomic profiling of ß-thalassemia patients specifically in Co, Mn, Ni, V and Ba, whereas the fold changes in Co, Mn, V and Ba were found to be greater than that in Fe, providing evidence that, in addition to Fe, other metals are also altered significantly and therefore chelation therapy for other metals may also needed in ß-thalassemia patients.


Assuntos
Espectrometria de Massas/métodos , Metais/sangue , Metais/metabolismo , Talassemia beta/metabolismo , Talassemia beta/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
17.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28801997

RESUMO

BACKGROUND: Low bone mass is common among adolescents with transfusion-dependent ß-thalassemia despite adequate transfusion and iron chelation. However, there are few reports regarding bone mineral density (BMD) among adolescents with nontransfusion-dependent thalassemia (NTDT). Indeed, only BMD data in patients with nontransfusion-dependent (NTD) ß-thalassemia intermedia have been reported. No previous study has investigated BMD among adolescents with NTD hemoglobin (Hb) E/ß-thalassemia. OBJECTIVE: To determine the prevalence of low bone mass among adolescents with NTD Hb E/ß-thalassemia and factors relating to low bone mass. METHODS: We investigated BMD of lumbar spine (L2-L4; BMDLS) and total body (BMDTB), as measured by dual-energy X-ray absorptiometry, in 22 adolescents (aged 13.2-20 years) with NTD Hb E/ß-thalassemia. RESULTS: Low bone mass was found to be 18.2% and 22.7% at the lumbar spine (BMDLS Z-score adjusted for bone age and height age) and 13.6% and 9.1% at the total body (BMDTB Z-score adjusted for bone age and height age). Patients with mean Hb level <8 g/dl were more likely to have low bone mass (BMDLS and BMDTB Z-scores adjusted for bone age) compared to those with Hb level ≥ 8 g/dl. Mean Hb level correlated with BMDLS and BMDTB Z-scores adjusted for bone age. CONCLUSION: We demonstrated that a low Hb level was associated with low bone mass among adolescents with NTD Hb E/ß-thalassemia. A significant proportion of low bone mass among these patients highlights the importance of appropriate management, including red cell transfusion, vitamin D and calcium supplementation for improved long-term bone health.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Vértebras Lombares , Talassemia beta , Adolescente , Adulto , Feminino , Hemoglobina E , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/metabolismo , Vértebras Lombares/fisiopatologia , Masculino , Índice de Gravidade de Doença , Talassemia beta/diagnóstico por imagem , Talassemia beta/metabolismo , Talassemia beta/fisiopatologia
18.
J Pediatr Hematol Oncol ; 40(1): 56-59, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29200160

RESUMO

OBJECTIVE: To assess the prevalence of impaired glucose tolerance in ß-thalassemia major and correlate it with chelation therapy. MATERIALS AND METHODS: Sixty-seven subjects with ß-thalassemia major, aged 1 to 20 years, were enrolled in our prospective cohort. Clinical details were recorded. Baseline oral glucose tolerance test, serum insulin, C peptide, and insulin resistance were measured. The biochemical profile was repeated after 6 months. RESULTS: The mean age of subjects was 7.43±4.48 years. Eight (11.9%) subjects had impaired fasting glucose, 7 (10.4%) had impaired glucose tolerance, and 1 (1.4%) subject had diabetes at baseline. Subjects with abnormal glucose profile had longer disease duration (95% confidence interval [CI] of difference=-6.64 to -0.68; P=0.019) and higher fasting blood glucose (95% CI of difference=-32.1 to -10.5; P=0.001) and serum ferritin (95% CI of difference=-219.8 to -3.4; P=0.001) than normoglycemic subjects. Insulin resistance and serum ferritin showed significant increase at 6 months (P<0.001 and P=0.001, respectively). Patients on deferiprone alone significantly improved glucose homeostasis on follow-up than those on desferrioxamine or combination therapy of desferrioxamine and deferiprone (P<0.05). CONCLUSIONS: Prolonged disease duration and higher serum ferritin adversely affects glucose homeostasis in thalassemic children. Deferiprone was the most effective chelator to improve glucose homeostasis in chronically transfused thalassemics.


Assuntos
Glicemia/fisiologia , Terapia por Quelação , Desferroxamina/uso terapêutico , Intolerância à Glucose/tratamento farmacológico , Homeostase/efeitos dos fármacos , Piridonas/uso terapêutico , Talassemia beta/complicações , Adolescente , Glicemia/efeitos dos fármacos , Criança , Pré-Escolar , Deferiprona , Desferroxamina/farmacologia , Feminino , Ferritinas/sangue , Intolerância à Glucose/etiologia , Intolerância à Glucose/fisiopatologia , Humanos , Lactente , Resistência à Insulina , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Masculino , Estudos Prospectivos , Piridonas/farmacologia , Adulto Jovem , Talassemia beta/sangue , Talassemia beta/metabolismo , Talassemia beta/terapia
19.
Blood Rev ; 31(6): 400-405, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28755795

RESUMO

As the main iron transporter, transferrin delivers iron to target tissues like the bone marrow for erythropoiesis. Also, by binding free iron, transferrin prevents formation of reactive oxygen species. Transferrin deficiency due to congenital hypotransferrinemia is characterized by anemia as well as oxidative stress related to toxic free iron. Transferrin supplementation may be beneficial in two ways. First, transferrin can correct anemia by modulating the amount of iron that is available for erythropoiesis. This is obvious for patients that suffer from hypotransferrinemia, but may also have beneficial effects for ß-thalassemia patients. Second, under conditions of iron overload, transferrin reduces oxidative stress by binding free iron in the circulation and in tissues. Hereby, transferrin protects the host against the reactive oxygen species that can be formed as a consequence of free iron. This beneficial effect is shown in hematological patients undergoing chemotherapy and stem cell transplantation. Transferrin may also be beneficial in lung injury, ischemia-reperfusion injury and hypomyelination. This review summarizes the preclinical and clinical data on the efficacy of exogenous transferrin administration to modulate certain forms of anemia and to prevent the toxic effects of free iron. Thereby, we show that transferrin has promising therapeutic potential in a wide variety of conditions.


Assuntos
Anemia/tratamento farmacológico , Transferrina/uso terapêutico , Anemia/metabolismo , Animais , Doenças Desmielinizantes/tratamento farmacológico , Doenças Desmielinizantes/metabolismo , Humanos , Hiperóxia/tratamento farmacológico , Hiperóxia/metabolismo , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/metabolismo , Degeneração Macular/tratamento farmacológico , Degeneração Macular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Transplante de Células-Tronco/métodos , Talassemia beta/tratamento farmacológico , Talassemia beta/metabolismo
20.
Redox Rep ; 22(6): 430-438, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28288539

RESUMO

BACKGROUND: Ischemia-modified albumin (IMA) is an altered type of serum albumin that forms under conditions of oxidative stress and an independent predictor of major adverse cardiovascular events. OBJECTIVES: To measure the levels of IMA in 45 children and adolescents with ß-thalassemia major (ß-TM) compared with 30 healthy controls and assess its relation to lipid peroxidation, vascular complications and subclinical atherosclerosis. METHODS: ß-TM patients without symptoms of heart disease were studied focusing on transfusion history, chelation therapy, serum ferritin, malondialdehyde (MDA) and IMA levels. Echocardiography was performed and carotid intima media thickness (CIMT) was assessed. RESULTS: IMA and MDA levels were significantly higher in ß-TM patients compared with controls (p < 0.001). IMA was higher among patients with heart disease, pulmonary hypertension risk and serum ferritin ≥2500 µg/l than those without. TM patients compliant to chelation had significantly lower IMA levels. IMA levels were positively correlated to MDA and CIMT while negatively correlated to ejection fraction and fractional shortening. CONCLUSION: Our results highlight the role of oxidative stress in the pathophysiology of vascular complications in thalassemia. IMA could be useful for screening of ß-TM patients at risk of cardiopulmonary complications and atherosclerosis because its alteration occurs in early subclinical disease.


Assuntos
Aterosclerose/metabolismo , Aterosclerose/patologia , Biomarcadores/metabolismo , Albumina Sérica Humana/metabolismo , Doenças Vasculares/metabolismo , Doenças Vasculares/patologia , Talassemia beta/metabolismo , Talassemia beta/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Adulto Jovem
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