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1.
Pol Arch Intern Med ; 133(2)2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36779522

RESUMO

Anemia of inflammation (AI) is a very frequent clinical condition affecting globally more than a billion people with chronic inflammatory disorders, such as chronic kidney disease, heart failure, and inflammatory bowel disease. It is usually associated with iron deficiency (ID), which imposes a severe additional burden on the recovery from the primary disease. The pathophysiology of iron dysregulation that may ultimately lead to absolute iron deficiency anemia (IDA) during inflammation is multifactorial and includes reduced iron absorption in the bowel, iron retention in macrophages of the reticuloendothelial system, reduction in circulatory half­life of erythrocytes, inadequate production and activity of erythropoietin, and impaired proliferation and differentiation of erythroid progenitor cells. These result in hypoferremia and iron-restricted erythropoiesis. AI is mostly mild to moderate, normochromic and normocytic with normal or even increased ferritin levels. The current treatment options for AI include iron replacement therapy, treatment with erythropoiesis­stimulating agents, and red blood cell transfusion. ID management is based on oral or intravenous iron preparations. Given the pathophysiology, treatment with oral iron, although widely used, presents several limitations that impact its effectiveness in patients with chronic inflammatory conditions. Instead, intravenous iron preparations are a valuable option for patients with chronic inflammatory diseases, as they overcome reduced bowel absorption. Novel therapeutic approaches include downregulation of hepcidin synthesis and function, and stabilization of the hypoxia­inducible factor via inhibition of prolyl hydroxylase domain. Several studies in vitro and in vivo are ongoing; however, the results in humans are still elusive.


Assuntos
Anemia , Ferro , Humanos , Anemia/tratamento farmacológico , Doença Crônica , Eritropoese , Inflamação
3.
Blood Transfus ; 19(3): 261-268, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33196416

RESUMO

BACKGROUND: Migration has impacted the spread of thalassaemia which is gradually becoming a global health problem. Italy, with an approximate estimation of 7,000 patients, does not have an accurate national record for haemoglobinopathies. This cross-sectional evaluation includes data for approximately 50% of beta-thalassaemia patients in Italy to provide an overview of the burden of thalassaemia syndromes. MATERIALS AND METHODS: The analysis included data on epidemiology, transfusions and clinical parameters from 3,986 thalassaemia patients treated at 36 centres in Italy who were alive on 31st December 2017. The study used WebThal, a computerised clinical record that is completely free-of-charge and that does not have any mandatory fields to be filled. RESULTS: For patients with thalassaemia major, 68% were aged ≥35 years and 11% were aged ≤18 years. Patients with thalassaemia intermedia were slightly older. Transfusion data, reported in a subgroup of 1,162 patients, showed 9% had pre-transfusion haemoglobin <9 g/dL, 63% had levels between ≥9 and <10 g/dL, and 28% had levels ≥10 g/dL. These 1,162 patients underwent 22,272 transfusion days during 2017, with a mean of 19 transfusion days/year/patient (range 1-54 days). Severity of iron overload was reported in 756 patients; many had moderate or mild liver iron load (74% had liver iron <7.5 mg/g dry weight). In the same cohort, 85% of patients had no signs of cardiac iron load (MRT2* >20 ms), and only 3% showed signs of high-risk heart condition (T2* <10 ms). Most patients had normal alanine amino transferase levels due to treatment with the new anti-hepatitis C virus (HCV) drugs. DISCUSSION: This study provides an overview of the current health status of patients with thalassaemia in Italy. Moreover, these data support the need for a national comprehensive thalassaemia registry.


Assuntos
Transfusão de Sangue , Talassemia/epidemiologia , Talassemia/terapia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Sobrecarga de Ferro/epidemiologia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Talassemia/sangue , Adulto Jovem
5.
Genet Med ; 21(11): 2605-2613, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31073229

RESUMO

With the advent of precision and genomic medicine, a critical issue is whether a disease gene variant is pathogenic or benign. Such is the case for the three autosomal dominant acute hepatic porphyrias (AHPs), including acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria, each resulting from the half-normal enzymatic activities of hydroxymethylbilane synthase, coproporphyrinogen oxidase, and protoporphyrinogen oxidase, respectively. To date, there is no public database that documents the likely pathogenicity of variants causing the porphyrias, and more specifically, the AHPs with biochemically and clinically verified information. Therefore, an international collaborative with the European Porphyria Network and the National Institutes of Health/National Center for Advancing Translational Sciences/National Institute of Diabetes and Digestive and Kidney Diseases (NIH/NCATS/NIDDK)-sponsored Porphyrias Consortium of porphyria diagnostic experts is establishing an online database that will collate biochemical and clinical evidence verifying the pathogenicity of the published and newly identified variants in the AHP-causing genes. The overall goal of the International Porphyria Molecular Diagnostic Collaborative is to determine the pathogenic and benign variants for all eight porphyrias. Here we describe the overall objectives and the initial efforts to validate pathogenic and benign variants in the respective heme biosynthetic genes causing the AHPs.


Assuntos
Porfirias/genética , Porfirias/fisiopatologia , Virulência/genética , Curadoria de Dados/métodos , Bases de Dados Factuais , Feminino , Humanos , Masculino , Patologia Molecular , Sintase do Porfobilinogênio/deficiência , Sintase do Porfobilinogênio/genética , Porfiria Aguda Intermitente/genética , Porfiria Aguda Intermitente/fisiopatologia , Porfirias Hepáticas/genética , Porfirias Hepáticas/fisiopatologia , Estados Unidos
6.
PLoS One ; 13(3): e0193582, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29494697

RESUMO

PURPOSE: To identify systemic risk factors for sickle cell maculopathy, and to analyze the microstructure of the macula of Sickle Cell Disease (SCD) patients by using automated segmentation of individual retinal layers. METHODS: Thirty consecutive patients with SCD and 30 matched controls underwent spectral-domain optical coherence tomography (SD-OCT) and automated thickness measurement for each retinal layer; thicknesses for SCD patients were then compared to normal controls. Demographic data, systemic data, and lab results were collected for each SCD patient; multivariate logistic regression analysis was used to identify potential risk factors for sickle cell maculopathy. RESULTS: Ongoing chelation treatment (p = 0.0187) was the most predictive factor for the presence of sickle cell maculopathy; the odds were 94.2% lower when chelation was present. HbF level tended to influence sickle cell maculopathy (p = 0.0775); the odds decreased by 12.9% when HbF increased by 1%. Sickle cell maculopathy was detected in 43% of SCD patients as patchy areas of retinal thinning on SD-OCT thickness map, mostly located temporally to the macula, especially in eyes with more advanced forms of sickle cell retinopathy (p = 0.003). In comparison to controls, SCD patients had a subtle thinning of the overall macula and temporal retina compared to controls (most p<0.0001), involving inner and outer retinal layers. Thickening of the retinal pigment epithelium was also detected in SCD eyes (p<0.0001). CONCLUSIONS: Chronic chelation therapy and, potentially, high levels of HbF are possible protective factors for the presence of sickle cell maculopathy, especially for patients with more advanced forms of sickle cell retinopathy. A subtle thinning of the overall macula occurs in SCD patients and involves multiple retinal layers, suggesting that ischemic vasculopathy may happen in both superficial and deep capillary plexi. Thinning of the outer retinal layers suggests that an ischemic insult of the choriocapillaris may also occur in SCD patients.


Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Terapia por Quelação/métodos , Macula Lutea/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Adulto , Idoso , Anemia Falciforme/metabolismo , Feminino , Hemoglobina Fetal/metabolismo , Angiofluoresceinografia/métodos , Humanos , Macula Lutea/metabolismo , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doenças Retinianas/metabolismo , Fatores de Risco , Tomografia de Coerência Óptica/métodos , Adulto Jovem
7.
PLoS One ; 13(2): e0192890, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466447

RESUMO

BACKGROUND: Iron overload-related heart failure is the principal cause of death in transfusion dependent patients, including those with Thalassemia Major. Linking cardiac siderosis measured by T2* to therapy improves outcomes. T1 mapping can also measure iron; preliminary data suggests it may have higher sensitivity for iron, particularly for early overload (the conventional cut-point for no iron by T2* is 20ms, but this is believed insensitive). We compared T1 mapping to T2* in cardiac iron overload. METHODS: In a prospectively large single centre study of 138 Thalassemia Major patients and 32 healthy controls, we compared T1 mapping to dark blood and bright blood T2* acquired at 1.5T. Linear regression analysis was used to assess the association of T2* and T1. A "moving window" approach was taken to understand the strength of the association at different levels of iron overload. RESULTS: The relationship between T2* (here dark blood) and T1 is described by a log-log linear regression, which can be split in three different slopes: 1) T2* low, <20ms, r2 = 0.92; 2) T2* = 20-30ms, r2 = 0.48; 3) T2*>30ms, weak relationship. All subjects with T2*<20ms had low T1; among those with T2*>20ms, 38% had low T1 with most of the subjects in the T2* range 20-30ms having a low T1. CONCLUSIONS: In established cardiac iron overload, T1 and T2* are concordant. However, in the 20-30ms T2* range, T1 mapping appears to detect iron. These data support previous suggestions that T1 detects missed iron in 1 out of 3 subjects with normal T2*, and that T1 mapping is complementary to T2*. The clinical significance of a low T1 with normal T2* should be further investigated.


Assuntos
Sangue/diagnóstico por imagem , Técnicas de Imagem Cardíaca/métodos , Sobrecarga de Ferro/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Talassemia beta/diagnóstico por imagem , Adulto , Feminino , Humanos , Sobrecarga de Ferro/fisiopatologia , Modelos Lineares , Masculino , Estudos Prospectivos , Talassemia beta/fisiopatologia
8.
Hemoglobin ; 41(2): 131-133, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28696845

RESUMO

Although its prevalence is unknown, liver involvement by sickle cell disease is not uncommon and encompasses different clinical spectra including non cholestatic and cholestatic disorders. Few data have been provided on chronic sickle cell intrahepatic cholestasis (SCIC) clinical course, although cirrhosis has been reported in sickle cell disease. However, no effective therapeutic approaches have been recognized either to prevent or treat this condition. Here we present two cases of adult sickle cell disease patients with decompensated cirrhosis. Their liver biopsies showed sickle cell thrombi within the hepatic sinusoids. Despite erythroexchange (EEX) transfusions, both patients suffered from major sickle cell disease-related events, suggesting that EEX transfusions may not be enough to impact on advanced liver involvement by sickle cell disease.


Assuntos
Anemia Falciforme , Transfusão de Eritrócitos , Cirrose Hepática , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/patologia , Anemia Falciforme/terapia , Feminino , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-Idade
11.
Eur J Haematol ; 96(1): 19-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25691036

RESUMO

OBJECTIVES: Plasma markers in addition to serum ferritin (SF) may be useful for the assessment of iron overload; however, predictive utility may differ depending on underlying, transfusion-dependent, anemias. METHODS: Data were collected before and after 1 year of deferasirox treatment (end of study; EOS) from the large, 1-year EPIC (Evaluation of Patients' Iron Chelation with Exjade(®) ) study. Trends were evaluated between liver iron concentration (LIC), transferrin saturation (TfSat), predose labile plasma iron (LPI) and their relationship to SF categories in 1530 patients: thalassemia major (TM; n = 1114), myelodysplastic syndromes (MDS, n = 336), and sickle-cell disease (SCD, n = 80). RESULTS: Baseline and EOS SF values showed a clear and similar relationship to LIC for all disease groups. TfSat also showed a relationship to SF, most clearly in patients with SCD, where TfSat was lowest in the lowest relative SF category. Unlike SF or LIC, TfSat did not decrease at EOS in any disease group. Baseline LPI was raised in TM and MDS, but not in patients with SCD, decreasing at EOS in both patient groups. After 1 year of chelation therapy, there was a significant trend for greater LPI reduction in patients with TM achieving LIC <7 mg Fe/g dw (P = 0.0137). CONCLUSIONS: Despite limitations, SF showed the clearest relationship, of the plasma markers evaluated, to LIC before and after 1 year of deferasirox in patients with TM, MDS, and SCD. In patients with TM, changes in LPI with chelation show a significant relationship to EOS LIC and may provide an additional indicator of chelation response (clinicaltrials.gov identifier: NCT00171821).


Assuntos
Anemia , Benzoatos/administração & dosagem , Ferritinas/sangue , Sobrecarga de Ferro , Ferro/sangue , Transferrina/metabolismo , Triazóis/administração & dosagem , Anemia/sangue , Anemia/tratamento farmacológico , Biomarcadores/sangue , Deferasirox , Feminino , Seguimentos , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/tratamento farmacológico , Masculino
12.
Hemoglobin ; 39(3): 178-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25902180

RESUMO

ß-Thalassemia intermedia (ß-TI) is a clinical term describing a range of clinical phenotypes that are intermediate in severity between the carrier state and ß-thalassemia major (ß-TM). To characterize the molecular basis of ß-TI in Erbil Province, Northern Iraq, 83 unrelated patients were investigated. Detection of ß-globin gene mutations was carried out by reverse hybridization assay and direct gene sequencing. All patients were screened for the XmnI polymorphism by direct sequencing of HBG2 ((G)γ promoter gene). Detection of α-globin gene deletions and triplication was carried out using the reverse hybridization assay. Four main molecular patterns were identified in association with the ß-TI phenotype, namely: ß(+)/ß(+) (38.5%), ß(+)/ß(0) (21.6%), ß(0)/ß(0) (31.3%), and ß(0)/wild type (8.4%). IVS-I-6 (T > C) was the most frequently encountered mutation (55 alleles, 34.6%), followed by IVS-II-1 (G > A) and codon 8 (-AA); furthermore, we report for the first time from Iraq two ß(+) mutations, -87 (C > G) and 5' untranslated region (5'UTR) +22 (G > A). The XmnI polymorphism was detected in 47.0% of patients, mainly in association with the ß(0)/ß(0) genotype. The α-globin gene deletions were encountered in four cases, including one case with (- -(FIL)) double gene deletion, a report that is the first from our country. The α-globin gene triplication was detected in five of the seven heterozygous ß-thalassemia (ß-thal) patients. Similar to other Mediterranean countries, inheritance of mild ß-globin mutations was the main molecular pattern underlying ß-TI in our patients followed by the ameliorating effect of the XmnI polymorphism.


Assuntos
Etnicidade/genética , Mutação , Globinas beta/genética , Talassemia beta/epidemiologia , Talassemia beta/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Códon , Índices de Eritrócitos , Feminino , Frequência do Gene , Genótipo , Humanos , Iraque/epidemiologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem , Talassemia beta/diagnóstico
13.
Hemoglobin ; 38(5): 351-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25271993

RESUMO

The increase in survival rate of ß-thalassemia (ß-thal) patients allowed for the appearance and manifestation of several complications in almost every organ system. Priapism in ß-thal patients is rarely reported in the literature. We herein report and investigate the occurrence of two cases of priapism in two young patients with ß-thal intermedia (ß-TI). The potential mechanisms are due to either a cellular mechanism involving a thrombus obstructing the efferent venules of the corpora cavernosa leading to priapism, or a recently elucidated functional mechanism that causes alteration of nitric oxide (NO) response of the penis, ultimately causing priapism. This should incite clinicians for a close follow-up and monitoring of high risk patients who are susceptible to developing priapism.


Assuntos
Priapismo/etiologia , Talassemia beta/fisiopatologia , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Terapia Combinada , Combinação de Medicamentos , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Masculino , Priapismo/prevenção & controle , Propranolol/uso terapêutico , Pseudoefedrina/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento , Triprolidina/uso terapêutico , Talassemia beta/tratamento farmacológico , Talassemia beta/terapia
15.
Ophthalmology ; 121(3): 709-18, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24314836

RESUMO

PURPOSE: To determine the prevalence and spectrum of ocular fundus abnormalities in patients with ß-thalassemia and to investigate risk factors for their development. DESIGN: Cross-sectional, observational study. PARTICIPANTS: A total of 255 patients with ß-thalassemia major (TM) and ß-thalassemia intermedia (TI) were consecutively recruited and investigated. METHODS: Patients underwent best correct visual acuity, indirect ophthalmoscopy, and fundus photography, including fundus autofluorescence (FAF) and near-infrared reflectance imaging using a confocal scanning laser ophthalmoscope (cSLO). Hematologic parameters were determined, including mean ferritin levels, aspartate amino transferase, alanine amino transferase, calcium, pre-transfusion hemoglobin, history of splenectomy, and liver iron concentration. Factors associated with the ocular phenotype were assessed using logistic regression. MAIN OUTCOME MEASURES: Ocular phenotype as determined by clinical examination and used multimodal imaging. RESULTS: A total of 153 patients (60.0%) affected by TM and 102 patients (40.0%) affected by TI participated, of whom 216 (84.7%) were receiving iron-chelating therapy. Ocular fundus abnormalities characteristic of pseudoxanthoma elasticum (PXE) were detected by cSLO in 70 of 255 patients (27.8%) and included peau d'orange (19.6%), angioid streaks (12.9%), pattern dystrophy-like changes (7.5%), and optic disc drusen (2.0%). Pseudoxanthoma elasticum-like changes were more frequent in patients with TI (P<0.001). Patients with PXE-like fundus changes were older than patients without these fundus changes (P<0.001). In both patients with TI and TM, age (P = 0.001) and splenectomy (P = 0.001) had the strongest association with presence of PXE-like fundus changes in multivariate analyses. A total of 43 of 255 patients (16.9%) showed increased retinal vascular tortuosity independently of the PXE-like fundus changes, which was associated with aspartate amino transferase (P = 0.036), hemoglobin (P = 0.008), and ferritin levels (P = 0.005). CONCLUSIONS: Pseudoxanthoma elasticum-like fundus changes are a frequent finding in patients with ß-thalassemia. In TI, these changes increase with duration or severity of the disease. This particular ocular phenotype suggests an ocular pathology similar to PXE. Retinal vascular tortuosity may be an additional disease manifestation independent of the PXE-like syndrome. Patients with long-standing disease requiring iron-chelating treatment and a history of splenectomy need regular ophthalmic checkups because they are at risk of developing PXE-like fundus changes and potentially of subsequent choroidal neovascularization.


Assuntos
Pseudoxantoma Elástico/diagnóstico , Talassemia beta/diagnóstico , Adolescente , Adulto , Idoso , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Cálcio/sangue , Criança , Corantes , Estudos Transversais , Feminino , Ferritinas/sangue , Angiofluoresceinografia , Hemoglobinas/metabolismo , Humanos , Verde de Indocianina , Quelantes de Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Fenótipo , Prevalência , Estudos Prospectivos , Pseudoxantoma Elástico/sangue , Pseudoxantoma Elástico/tratamento farmacológico , Fatores de Risco , Acuidade Visual , Adulto Jovem , Talassemia beta/sangue , Talassemia beta/tratamento farmacológico
16.
J Hypertens ; 31(11): 2259-69, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24029866

RESUMO

BACKGROUND AND AIM: Iron is the most abundant metal in mammalian cells, and plays a pivotal role in many metabolic processes. Dysregulated iron homeostasis is involved in the cause of a number of pathological processes including renal diseases. METHODS AND RESULTS: Longitudinal MRI scans of salt-loaded spontaneously hypertensive stroke-prone rats (SHRSP), an animal model that spontaneously develops hypertensive nephropathy, showed a decrease in renal and hepatic T2 SI (a sign of iron accumulation) of, respectively, 42.3 ±â€Š2.5% (P < 0.01) and 60.4 ±â€Š15.1% (P < 0.01) in comparison with SHRSP fed a standard diet. This was accompanied by the development of renal inflammation and oxidative stress (as evaluated by immunohistochemical and proteomic analyses), mitochondrial dysfunction, massive proteinuria and sustained intravascular hemolysis with the subsequent depletion of plasma haptoglobin, which was responsible for the renal uptake of hemoglobin and iron accumulation. In order to investigate the role of iron in these pathological processes, we subcutaneously treated the salt-loaded rats with the iron chelator deferoxamine (200 mg/kg per day). The pharmacological treatment prevented iron tissue accumulation, as indicated by the increase in renal and hepatic T2 SI of, respectively, 120.0 ±â€Š10.1% (P < 0.01) and 73.9 ±â€Š4.4% (P < 0.01) in comparison with salt-loaded rats treated with vehicle alone. Deferoxamine also preserved renal morphology and function, the renal infiltration of ED-1-positive macrophages/monocytes, and the expression of MCP-1 and TGF-ß mRNA, reduced the level of reactive oxygen species, and improved the activity of mitochondrial cytochrome c oxidase. CONCLUSION: These findings suggest that iron dysmetabolism is involved in the development of hypertensive nephropathy in SHRSP.


Assuntos
Hipertensão Renal/metabolismo , Ferro/metabolismo , Ferro/fisiologia , Nefrite/metabolismo , Animais , Pressão Sanguínea , Desferroxamina/farmacologia , Modelos Animais de Doenças , Hemólise/fisiologia , Homeostase , Hipertensão Renal/etiologia , Rim/fisiopatologia , Masculino , Modelos Animais , Nefrite/etiologia , Estresse Oxidativo , Proteinúria/etiologia , Proteinúria/metabolismo , Proteômica , Ratos , Ratos Endogâmicos SHR , Espécies Reativas de Oxigênio/metabolismo , Cloreto de Sódio na Dieta/administração & dosagem , Cloreto de Sódio na Dieta/metabolismo , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Fator de Crescimento Transformador beta/metabolismo
17.
Curr Opin Hematol ; 20(3): 187-92, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23426199

RESUMO

PURPOSE OF REVIEW: The aim is to overview recent evidence on consequences, assessment, and management of iron overload in transfusion-independent patients with ß-thalassemia intermedia. RECENT FINDINGS: Despite their transfusion-independence, ß-thalassemia intermedia patients can still accumulate iron due to increased intestinal absorption. Recent observational studies show that iron burden in this group of patients can ultimately reach considerably high thresholds, and leads to a variety of serious morbidities involving the liver, endocrine glands, and arguably the vascular system. The diagnosis of iron overload in this patient population can follow established guidelines from ß-thalassemia major patients, although with careful interpretation of spot serum ferritin levels. Data from a recent randomized clinical trial demonstrated the efficacy and safety of iron chelation therapy in decreasing liver iron concentration in this group of patients, which may ultimately help in reducing morbidity risk. SUMMARY: Iron overload in transfusion-independent patients with ß-thalassemia intermedia deserves careful attention, and prompt diagnosis and management are recommended.


Assuntos
Sobrecarga de Ferro/etiologia , Talassemia beta/complicações , Humanos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/terapia , Talassemia beta/terapia
18.
Nephrol Dial Transplant ; 28(7): 1733-43, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23345622

RESUMO

BACKGROUND: Anemia is a common complication of chronic kidney disease (CKD) that negatively impacts the quality of life and is associated with numerous adverse outcomes. Excess levels of the iron regulatory hormone hepcidin are thought to contribute to anemia in CKD patients by decreasing iron availability from the diet and from body stores. Adenine treatment in rats has been proposed as an animal model of anemia of CKD with high hepcidin levels that mirrors the condition in human patients. METHODS: We developed a modified adenine-induced kidney disease model with a higher survival rate than previously reported models, while maintaining persistent kidney disease and anemia. We then tested whether the small molecule bone morphogenetic protein (BMP) inhibitor LDN-193189, which was previously shown to lower hepcidin levels in rodents, mobilized iron into the plasma and improved iron-restricted erythropoiesis in this model. RESULTS: Adenine-treated rats exhibited increased hepatic hepcidin mRNA, decreased serum iron, increased spleen iron content, low hemoglobin (Hb) and inappropriately low erythropoietin (EPO) levels relative to the degree of anemia. LDN-193189 administration to adenine-treated rats lowered hepatic hepcidin mRNA, mobilized stored iron into plasma and increased Hb content of reticulocytes. CONCLUSIONS: Our data suggest that hepcidin lowering agents may provide a new therapeutic strategy to improve iron availability for erythropoiesis in CKD.


Assuntos
Adenina/toxicidade , Anemia Ferropriva/tratamento farmacológico , Modelos Animais de Doenças , Eritrócitos/efeitos dos fármacos , Hepcidinas/metabolismo , Ferro/metabolismo , Nefropatias/complicações , Pirazóis/farmacologia , Pirimidinas/farmacologia , Anemia Ferropriva/sangue , Anemia Ferropriva/etiologia , Animais , Anti-Infecciosos/antagonistas & inibidores , Anti-Infecciosos/metabolismo , Western Blotting , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Ensaio de Imunoadsorção Enzimática , Eritrócitos/citologia , Eritrócitos/metabolismo , Eritropoese/efeitos dos fármacos , Hepcidinas/antagonistas & inibidores , Humanos , Nefropatias/sangue , Nefropatias/induzido quimicamente , Masculino , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Haematologica ; 98(5): 691-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22983591

RESUMO

Genomic DNA of 3 patients, born as healthy carriers and developing a late-onset severe transfusion-dependent beta-thalassemia major was studied by high-density genome wide SNP array analysis. A mosaic loss of heterozygosity for almost the entire 11p was found, not attributable to deletions but involving mosaicism for segmental paternal isodisomy of 11p. Mitotic recombination leading to mosaic segmental uniparental isodisomy on chromosome 11p in multiple tissues has been described as a molecular disease mechanism for a subset of sporadic Beckwith-Wiedemann syndrome cases. A similar mechanism also seems to be involved in causing late-onset disease in carriers of recessive mutations in other genes located in 11p, such as late-onset beta-thalassemia major and sickle cell disease. We suggest that the loss of maternally imprinted IGF-2 and H19 genes may account for the selective advantage of hematopoietic cells containing this segmental paternal isodisomy of 11p carrying the ß-thalassemia mutation.


Assuntos
Mosaicismo , Dissomia Uniparental , Talassemia beta/genética , Talassemia beta/metabolismo , Adolescente , Adulto , Fatores Etários , Alelos , Criança , Cromossomos Humanos Par 11 , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Mutação , Linhagem , Polimorfismo de Nucleotídeo Único , Adulto Jovem , Globinas beta/genética , Talassemia beta/diagnóstico
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