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1.
Acta Cir Bras ; 35(3): e202000301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401830

RESUMO

PURPOSE: To analyze the serum levels of nitric oxide and correlate them with the levels of thiobarbituric acid reactive substances (TBARS) in liver, brain and spinal cord of animals using L-NAME and treated with hydroxyurea. METHODS: Eighteen male albino Wistar rats were divided into three groups. NG-nitro-L-arginine methyl ester (L-NAME) was intraperitoneally administered to induce oxidative stress. TBARS and plasma nitric oxide levels were analyzed in all groups. Histopathology of the liver and vascular tissue was performed. RESULTS: Statistically significant differences were seen in liver, brain and spinal cord TBARS levels. CONCLUSIONS: Following the use of L-NAME, hepatic tissue increased the number of Kupffer cells as oxidative stress and inflammatory response increased. The use of L-NAME caused an increase in lipid peroxidation products and, consequently, in oxidative stress in animals. Hydroxyurea doses of 35 mg / kg / day reduced TBARS values in liver, brain and spinal cord.


Assuntos
Anemia Falciforme/tratamento farmacológico , Encéfalo/metabolismo , Hidroxiureia/uso terapêutico , Fígado/metabolismo , Estresse Oxidativo/fisiologia , Medula Espinal/metabolismo , Anemia Falciforme/metabolismo , Anemia Falciforme/fisiopatologia , Animais , Modelos Animais de Doenças , Masculino , NG-Nitroarginina Metil Éster , Ratos , Ratos Wistar
2.
Subcell Biochem ; 94: 297-322, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189305

RESUMO

Sickle cell hemoglobin (HbS) is an example of a genetic variant of human hemoglobin where a point mutation in the ß globin gene results in substitution of glutamic acid to valine at sixth position of the ß globin chain. Association between tetrameric hemoglobin molecules through noncovalent interactions between side chain residue of ßVal6 and hydrophobic grooves formed by ßAla70, ßPhe85 and ßLeu88 amino acid residues of another tetramer followed by the precipitation of the elongated polymer leads to the formation of sickle-shaped RBCs in the deoxygenated state of HbS. There are multiple non-covalent interactions between residues across intra- and inter-strands that stabilize the polymer. The clinical phenotype of sickling of RBCs manifests as sickle cell anemia, which was first documented in the year 1910 in an African patient. Although the molecular reason of the disease has been understood well over the decades of research and several treatment procedures have been explored to date, an effective therapeutic strategy for sickle cell anemia has not been discovered yet. Surprisingly, it has been observed that the oxy form of HbS and glutathionylated form of deoxy HbS inhibits polymerization. In addition to describe the residue level interactions in the HbS polymer that provides its stability, here we explain the mechanism of inhibition in the polymerization of HbS in its oxy state. Additionally, we reported the molecular insights of inhibition in the polymerization for glutathionyl HbS, a posttranslational modification of hemoglobin, even in its deoxy state. In this chapter we briefly consider the available treatment procedures of sickle cell anemia and propose that the elevation of glutathionylation of HbS within RBCs, without inducing oxidative stress, might be an effective therapeutic strategy for sickle cell anemia.


Assuntos
Anemia Falciforme/metabolismo , Hemoglobinas/química , Hemoglobinas/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/patologia , Anemia Falciforme/terapia , Eritrócitos/química , Eritrócitos/metabolismo , Eritrócitos/patologia , Hemoglobinas/genética , Humanos , Polimerização
3.
Ann Hematol ; 99(5): 925-935, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32157419

RESUMO

Sickle cell disease (SCD) is an autosomal recessive blood disorder which occurs due to point mutation in the ß-globin chain of hemoglobin. Since the past decades, various therapies have been put forth, which are based on obstructing pathophysiological mechanisms of SCD including inhibition of Gardos channel and cation fluxes which in turn prevents sickle erythrocyte destruction and dehydration. The pharmacological approaches are based on the mechanism of reactivating γ-globin expression by utilizing fetal hemoglobin (HbF)-inducing drugs such as hydroxyurea. In SCD, gene therapy could be considered as a promising tool which involves modifying mutation at the gene-specific target by either promoting insertion or deletion of globins. Although there are various therapies emerged so far in the treatment of SCD, many of them have faced a major setback in most of developing countries in terms of cost, unavailability of expertise, and suitable donor. Therefore, in addition to pathophysiological aspects, this review will discuss new advancements and approaches made in the therapeutic domain of SCD including a viewpoint of modulating hemoglobin in SCD by the intervention of probiotics.


Assuntos
Anemia Falciforme , Eritrócitos Anormais , Hemoglobina Fetal , Hidroxiureia/uso terapêutico , Canais de Potássio Ativados por Cálcio de Condutância Intermediária , Probióticos/uso terapêutico , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/genética , Anemia Falciforme/metabolismo , Anemia Falciforme/fisiopatologia , Eritrócitos Anormais/metabolismo , Eritrócitos Anormais/patologia , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo
4.
PLoS One ; 15(2): e0229105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084188

RESUMO

Brain artery velocities (Time-Averaged Maximum Mean Velocity, TAMMV) by Transcranial Doppler (TCD), hematocrit, hemoglobin, Red blood cell (RBC) Distribution Width (RDW) and RBC rigidity index (Ri), when reported together with their correlations, provide a accurate and useful diagnostic picture than blood viscosity measurements alone. Additionally, our study included a sixth parameter provided by TCD, the Gosling Pulsatility Index PI, which is an indicator of CBF (Cerebral Blood Flow) resistance. All these parameters are routine in Hematology except for values of Ri. The rigidity (Ri) of the RBC is the main rheological characteristic of the blood of Sickle Cell Anemia (SCA) patients and several pathologies. However, its quantification depends on many commercial and experimental techniques, none disseminated and predominant around the World. The difference in absorbance values of the blood, during the process of sedimentation in a microwell of a Microplate Reader, is a straightforward way of semi-quantifying the RBC rigidity Ri, since the fraction of irreversibly sickled red blood cells does not form rouleaux. Erythrocyte Rigidity Index (Ri) was calculated using initial absorbance Ainitial (6 s) and final Afinal (540 s), Ri = 1 / (Ai-Af). The Ri of 119 patients (2-17 y / o, M & F) SCA, SCC (Sickle Cell/hemoglobin C), SCD (Sickle Cell/hemoglobin D), Sß0thal (Sickle Cell/hemoglobin Beta Zero Thalassemia) and 71 blood donors (20-65 y / o, M & F) were measured in our laboratory while the five parameters (TAMMV and PI by TCD, Hct, Hb and RDW) were obtained from medical records. The in vitro addition of hydroxyurea (HU, 50mg /dl, n = 51 patients, and n = 8 healthy donors) in the samples decreased the rouleaux adhesion strength of both donor and patients' blood samples, leading to extraordinarily high Ri values. The correlation between the studied parameters was especially significant for the direct relationships between Ri, TAMMV, and PI.


Assuntos
Eritrócitos/citologia , Eritrócitos/metabolismo , Adolescente , Adulto , Idoso , Anemia Falciforme/metabolismo , Velocidade do Fluxo Sanguíneo/fisiologia , Criança , Pré-Escolar , Índices de Eritrócitos , Feminino , Hematócrito , Hemoglobinas/metabolismo , Humanos , Hidroxiureia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
PLoS One ; 15(1): e0228399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31995624

RESUMO

Sickle cell disease (SCD) consists of a group of hemoglobinopathies in which individuals present highly variable clinical manifestations. Sickle cell anemia (SCA) is the most severe form, while SC hemoglobinopathy (HbSC) is thought to be milder. Thus, we investigated the clinical manifestations and laboratory parameters by comparing each SCD genotype. We designed a cross-sectional study including 126 SCA individuals and 55 HbSC individuals in steady-state. Hematological, biochemical and inflammatory characterization was performed as well as investigation of previous history of clinical events. SCA patients exhibited most prominent anemia, hemolysis, leukocytosis and inflammation, whereas HbSC patients had increased lipid determinations. The main cause of hospitalization was pain crises on both genotypes. Vaso-occlusive events and pain crises were associated with hematological, inflammatory and anemia biomarkers on both groups. Cluster analysis reveals hematological, inflammatory, hemolytic, endothelial dysfunction and anemia biomarkers in HbSC disease as well as SCA. The results found herein corroborate with previous studies suggesting that SCA and HbSC, although may be similar from the genetic point of view, exhibit different clinical manifestations and laboratory alterations which are useful to monitor the clinical course of each genotype.


Assuntos
Anemia Falciforme/metabolismo , Biomarcadores/análise , Hemoglobina Falciforme/genética , Adolescente , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/genética , Criança , Estudos Transversais , Feminino , Ácido Fólico/uso terapêutico , Genótipo , Doença da Hemoglobina SC/tratamento farmacológico , Doença da Hemoglobina SC/genética , Doença da Hemoglobina SC/metabolismo , Humanos , Hidroxiureia/uso terapêutico , Masculino
6.
Am J Hematol ; 95(2): 205-211, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31763707

RESUMO

70 years ago, Linus Pauling, the legendary genius of 20th century chemistry, published his famous work on the molecular cause of sickle cell disease, a paper that gave birth to what is now called molecular medicine. In this paper, Pauling left important questions unanswered that have motivated an enormous amount of scientific and clinical research since then. This retrospective discusses the basic science studies that have answered those questions directly related to the kinetics and thermodynamics of hemoglobin S polymerization.


Assuntos
Anemia Falciforme , Hemoglobina Falciforme , Polimerização , Anemia Falciforme/história , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Hemoglobina Falciforme/história , Hemoglobina Falciforme/metabolismo , História do Século XX , Humanos , Publicações Periódicas como Assunto/história
7.
Lipids Health Dis ; 18(1): 225, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861992

RESUMO

BACKGROUND: Hypocholesterolemia is the most frequently encountered lipid abnormality in sickle cell disease (SCD). We enrolled pediatric patients to determine the relationships between lipid profile and parameters of hemolysis, oxidative stress and chronic inflammation in SCD. METHODS: The study involved 35 pediatric SCD patients and 19 healthy controls. Patients were crisis-free and had not received transfusions for the last 3 months. Total cholesterol, triglyceride, HDL-C, LDL-C, VLDL-C, apolipoprotein A1, apolipoprotein B, LCAT, LDH, bilirubin, haptoglobin, iron, ferritin, hemin, serum amyloid A (SAA), myeloperoxidase (MPO), uric acid, ALT and GGT levels were evaluated in patients' blood. RESULTS: Patients had hypocholesterolemia depicted by lower levels of total cholesterol, HDL-C, LDL-C, as well as Apolipoprotein A1 and Apolipoprotein B compared to controls. The chronic hemolysis of SCD was evident in patients by higher LDH and bilirubin and almost undetectable haptoglobin levels. Hemin levels (as a measure of oxidized heme) were significantly increased in patients with SCD. Inflammation markers, SAA and MPO, were significantly increased in the patients as well. There were negative correlations between HDL-C and LDH, and Apo A1 and SAA. Hemin was positively correlated to MPO. CONCLUSION: Hemolysis was associated with decreased HDL -C, and Inflammation was linked to decreased apolipoprotein A1 levels in our SCD patients. Therefore, we suggest that the HDL particle is altered during the course of the disease. The altered HDL in SCD may become dysfunctional and result with a slowing down of the reverse cholesterol transport.


Assuntos
Anemia Falciforme/sangue , Apolipoproteína A-I/sangue , Colesterol/sangue , Inflamação/sangue , Adolescente , Adulto , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Apolipoproteína A-I/genética , Apolipoproteínas B/sangue , Bilirrubina/sangue , Biomarcadores/sangue , Criança , Colesterol/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Feminino , Hemólise , Humanos , Inflamação/metabolismo , Inflamação/patologia , L-Lactato Desidrogenase/sangue , Lipídeos/sangue , Masculino , Peroxidase/sangue , Proteína Amiloide A Sérica/metabolismo , Triglicerídeos/sangue , Adulto Jovem
8.
Molecules ; 24(24)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842406

RESUMO

Sickle cell disease (SCD) is a group of inherited disorders affecting red blood cells, which is caused by a single mutation that results in substitution of the amino acid valine for glutamic acid in the sixth position of the ß-globin chain of hemoglobin. These mutant hemoglobin molecules, called hemoglobin S, can polymerize upon deoxygenation, causing erythrocytes to adopt a sickled form and to suffer hemolysis and vaso-occlusion. Until recently, only two drug therapies for SCD, which do not even fully address the manifestations of SCD, were approved by the United States (US) Food and Drug Administration. A third treatment was newly approved, while a monoclonal antibody preventing vaso-occlusive crises is also now available. The complex nature of SCD manifestations provides multiple critical points where drug discovery efforts can be and have been directed. These notwithstanding, the need for new therapeutic approaches remains high and one of the recent efforts includes developments aimed at inhibiting the polymerization of hemoglobin S. This review focuses on anti-sickling approaches using peptide-based inhibitors, ranging from individual amino acid dipeptides investigated 30-40 years ago up to more promising 12- and 15-mers under consideration in recent years.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos , Desenho de Fármacos , Peptídeos , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Antidrepanocíticos/química , Antidrepanocíticos/uso terapêutico , Hemoglobina Falciforme/metabolismo , Humanos , Peptídeos/química , Peptídeos/uso terapêutico
10.
Blood ; 134(25): 2249-2260, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31697818

RESUMO

Sickle cell disease (SCD) leads to significant morbidity and early mortality, and hematopoietic cell transplantation (HCT) is the only widely available cure, with impacts seen on SCD-related organ dysfunction. Outcomes are excellent following matched-related donor (MRD) HCT, leading to significantly expanded application of this treatment over the past decade. The majority of SCD patients lack an MRD, but outcomes following alternative donor HCT continue to improve on clinical trials. Within this framework, we aim to provide our perspective on how to apply research findings to clinical practice, for an individual patient. We also emphasize that the preparation of SCD recipients for HCT and supporting them through HCT have special nuances that require awareness and close attention. Through the use of clinical vignettes, we provide our perpsective on the complex decision-making process in HCT for SCD as well as recommendations for the evaluation and support of these patients through HCT.


Assuntos
Anemia Falciforme/terapia , Transplante de Células-Tronco Hematopoéticas , Aloenxertos , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Criança , Feminino , Humanos , Masculino
11.
Pflugers Arch ; 471(11-12): 1539-1549, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31729557

RESUMO

Abnormal activity of red cell KCl cotransport (KCC) is involved in pathogenesis of sickle cell anaemia (SCA). KCC-mediated solute loss causes shrinkage, concentrates HbS, and promotes HbS polymerisation. Red cell KCC also responds to various stimuli including pH, volume, urea, and oxygen tension, and regulation involves protein phosphorylation. The main aim of this study was to investigate the role of the WNK/SPAK/OSR1 pathway in sickle cells. The pan WNK inhibitor WNK463 stimulated KCC with an EC50 of 10.9 ± 1.1 nM and 7.9 ± 1.2 nM in sickle and normal red cells, respectively. SPAK/OSR1 inhibitors had little effect. The action of WNK463 was not additive with other kinase inhibitors (staurosporine and N-ethylmaleimide). Its effects were largely abrogated by pre-treatment with the phosphatase inhibitor calyculin A. WNK463 also reduced the effects of physiological KCC stimuli (pH, volume, urea) and abolished any response of KCC to changes in oxygen tension. Finally, although protein kinases have been implicated in regulation of phosphatidylserine exposure, WNK463 had no effect. Findings indicate a predominant role for WNKs in control of KCC in sickle cells but an apparent absence of downstream involvement of SPAK/OSR1. A more complete understanding of the mechanisms will inform pathogenesis whilst manipulation of WNK activity represents a potential therapeutic approach.


Assuntos
Anemia Falciforme/metabolismo , Eritrócitos/metabolismo , Simportadores de Cloreto de Sódio-Potássio/metabolismo , Eritrócitos/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Pirrolidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
12.
Proc Natl Acad Sci U S A ; 116(50): 25236-25242, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31767751

RESUMO

Sickle cell disease (SCD) is caused by a variant hemoglobin molecule that polymerizes inside red blood cells (RBCs) in reduced oxygen tension. Treatment development has been slow for this typically severe disease, but there is current optimism for curative gene transfer strategies to induce expression of fetal hemoglobin or other nonsickling hemoglobin isoforms. All SCD morbidity and mortality arise directly or indirectly from polymer formation in individual RBCs. Identifying patients at highest risk of complications and treatment candidates with the greatest curative potential therefore requires determining the amount of polymer in individual RBCs under controlled oxygen. Here, we report a semiquantitative measurement of hemoglobin polymer in single RBCs as a function of oxygen. The method takes advantage of the reduced oxygen affinity of hemoglobin polymer to infer polymer content for thousands of RBCs from their overall oxygen saturation. The method enables approaches for SCD treatment development and precision medicine.


Assuntos
Anemia Falciforme/metabolismo , Eritrócitos/metabolismo , Hemoglobina Falciforme/metabolismo , Hemoglobinas/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Oxigênio/metabolismo , Eritrócitos/química , Eritrócitos/citologia , Hemoglobina Falciforme/química , Hemoglobinas/química , Humanos , Cinética , Oxigênio/química , Análise de Célula Única
13.
Ann Hematol ; 98(12): 2673-2681, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31478061

RESUMO

Sickle cell anemia (SCA) is an autosomal recessive monogenic disease with significant clinical variability. Cerebrovascular disease, particularly ischemic stroke, is one of the most severe complications of SCA in children. This study aimed to investigate the influence of genetic variants on the levels of fetal hemoglobin (Hb F) and biochemical parameters related with chronic hemolysis, as well as on ischemic stroke risk, in ninety-one unrelated SCA patients, children of sub-Saharan progenitors. Our results show that a higher Hb F level has an inverse relationship with the occurrence of stroke, since the group of patients who suffered stroke presents a significantly lower mean Hb F level (5.34 ± 4.57% versus 9.36 ± 6.48%; p = 0.024). Furthermore, the co-inheritance of alpha-thalassemia improves the chronic hemolytic pattern, evidenced by a decreased reticulocyte count (8.61 ± 3.58% versus 12.85 ± 4.71%; p < 0.001). In addition, our findings have confirmed the importance of HBG2 and BCL11A loci in the regulation of Hb F expression in sub-Saharan African SCA patients, as rs7482144_A, rs11886868_C, and rs4671393_A alleles are significantly associated with a considerable increase in Hb F levels (p = 0.019, p = 0.026, and p = 0.028, respectively). Concerning KLF1, twelve different variants were identified, two of them novel. Seventy-three patients (80.2%) presented at least one variant in this gene. However, no correlation was observed between the presence of these variants and Hb F level, severity of hemolysis, or stroke occurrence, which is consistent with their in silico-predicted minor functional consequences. Thus, we conclude that the prevalence of functional KLF1 variants in a sub-Saharan African background does not seem to be relevant to SCA clinical modulation.


Assuntos
Grupo com Ancestrais do Continente Africano , Anemia Falciforme , Isquemia Encefálica , Hemoglobina Fetal , Regulação da Expressão Gênica , Acidente Vascular Cerebral , Adolescente , Anemia Falciforme/complicações , Anemia Falciforme/etnologia , Anemia Falciforme/genética , Anemia Falciforme/metabolismo , Isquemia Encefálica/etnologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Criança , Pré-Escolar , Feminino , Hemoglobina Fetal/biossíntese , Hemoglobina Fetal/genética , Loci Gênicos , Humanos , Masculino , Acidente Vascular Cerebral/etnologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo
14.
Am J Physiol Cell Physiol ; 317(5): C993-C1000, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509446

RESUMO

Kidney disease, including proximal tubule (PT) dysfunction, and vitamin D deficiency are among the most prevalent complications in sickle cell disease (SCD) patients. Although these two comorbidities have never been linked in SCD, the PT is the primary site for activation of vitamin D. Precursor 25-hydroxyvitamin D [25(OH)D] bound to vitamin D-binding protein (DBP) is taken up by PT cells via megalin/cubilin receptors, hydroxylated to the active 1,25-dihydroxyvitamin D [1,25(OH)2D] form, and released into the bloodstream. We tested the hypothesis that cell-free hemoglobin (Hb) filtered into the PT lumen impairs vitamin D uptake and metabolism. Hb at concentrations expected to be chronically present in the ultrafiltrate of SCD patients competed directly with DBP for apical uptake by PT cells. By contrast, uptake of retinol binding protein was impaired only at considerably higher Hb concentrations. Prolonged exposure to Hb led to increased oxidative stress in PT cells and to a selective increase in mRNA levels of the CYP27B1 hydroxylase, although protein levels were unchanged. Hb exposure also impaired vitamin D metabolism in PT cells, resulting in reduced ratio of 1,25(OH)2D:25(OH)D. Moreover, plasma levels of 1,25(OH)2D were reduced in a mouse model of SCD. Together, our data suggest that Hb released by chronic hemolysis has multiple effects on PT function that contribute to vitamin D deficiency in SCD patients.


Assuntos
Anemia Falciforme/metabolismo , Hemoglobinas/metabolismo , Túbulos Renais Proximais/metabolismo , Proteína de Ligação a Vitamina D/metabolismo , Vitamina D/análogos & derivados , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/patologia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas/farmacologia , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Camundongos Transgênicos , Gambás , Vitamina D/metabolismo
15.
J Immunol ; 203(6): 1571-1578, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31413105

RESUMO

Heme is a critical danger molecule liberated from hemeproteins in various conditions, including from hemoglobin in hemolytic diseases. Heme may cause thromboinflammatory damage by activating inflammatory and hemostatic pathways, such as complement, the TLRs, coagulation, and platelets. In this study, we explored the effect of single and dual inhibition of complement component C5 and TLR coreceptor CD14 on heme-induced thromboinflammation in an ex vivo human whole blood model. Heme induced a dose-dependent activation of complement via the alternative pathway. Single inhibition of C5 by eculizumab attenuated the release of IL-6, IL-8, TNF, MCP-1, MIP-1α, IFN-γ, LTB-4, MMP-8 and -9, and IL-1Ra with more than 60% (p < 0.05 for all) reduced the upregulation of CD11b on granulocytes and monocytes by 59 and 40%, respectively (p < 0.05), and attenuated monocytic tissue factor expression by 33% (p < 0.001). Blocking CD14 attenuated IL-6 and TNF by more than 50% (p < 0.05). In contrast to single inhibition, combined C5 and CD14 was required for a significantly attenuated prothrombin cleavage (72%, p < 0.05). Markers of thromboinflammation were also quantified in two patients admitted to the hospital with sickle cell disease (SCD) crisis. Both SCD patients had pronounced hemolysis and depleted plasma hemopexin and haptoglobin. Plasma heme and complement activation was markedly increased in one patient, a coinciding observation as demonstrated ex vivo. In conclusion, heme-induced thromboinflammation was largely attenuated by C5 inhibition alone, with a beneficial effect of adding a CD14 inhibitor to attenuate prothrombin activation. Targeting C5 has the potential to reduce thromboinflammation in SCD crisis patients.


Assuntos
Complemento C5/metabolismo , Heme/metabolismo , Inflamação/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Adulto , Anemia Falciforme/metabolismo , Animais , Coagulação Sanguínea/fisiologia , Ativação do Complemento/fisiologia , Citocinas/metabolismo , Granulócitos/metabolismo , Hemólise/fisiologia , Humanos , Masculino , Monócitos/metabolismo , Suínos , Tromboplastina/metabolismo
16.
Exp Hematol ; 77: 51-60.e1, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31404577

RESUMO

Sickle cell disease (SCD) is a recessively inherited blood disorder caused by abnormal ß-globin production. The ß-globin mutation changes erythrocyte morphology into a sickle shape and increases erythrocyte vulnerability to hemolysis. Oxidative stress and concomitant inflammation eventually result in damage to multiple organs. Nrf2 is a master regulator of the oxidative stress response, homeostasis, and metabolism. Keap1 modulates Nrf2 protein levels; Nrf2 inducers alter nuclear Nrf2 levels by interacting with Keap1. Genetic modification of Keap1 helps to reduce inflammation and tissue damage in SCD model mice through Nrf2 induction. Here, we investigated the benefits of a mild and safe Nrf2 agonist, sulforaphane (SFN), in ameliorating SCD pathology in a murine model. SFN is a phytochemical and is found in cruciferous vegetables as its inert precursor, glucoraphanin. We found that dietary SFN administration for 14 days or 2 months increased the expression of Nrf2-dependent cytoprotective genes, but SFN uptake did not have deleterious effects on the food consumption and growth of SCD model mice. SFN ameliorated the liver damage of SCD mice, which could be validated by the rescue of liver function and the significantly reduced liver necrotic area. SFN administration also helped to eliminate heme released from lysed sickle cells. These results indicate that dietary supplementation with SFN relieves SCD symptoms by inducing Nrf2 and support our contention that SFN is a potential drug for the long-term treatment of children with SCD.


Assuntos
Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/metabolismo , Suplementos Nutricionais , Isotiocianatos/farmacologia , Hepatopatias/tratamento farmacológico , Hepatopatias/metabolismo , Fígado/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/patologia , Animais , Modelos Animais de Doenças , Feminino , Heme/genética , Heme/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado/patologia , Hepatopatias/genética , Hepatopatias/patologia , Masculino , Camundongos , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
17.
Clin Sci (Lond) ; 133(13): 1475-1486, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31273050

RESUMO

Hyperfiltration, highly prevalent early in sickle cell disease (SCD), is in part driven by an increase in ultrafiltration coefficient (Kf). The increase in Kf may be due to enlarged filtration surface area and/or increased glomerular permeability (Palb). Previous studies have demonstrated that endothelin-1 (ET-1) contributes to Palb changes in models of diabetes and SCD. Thus, we performed longitudinal studies of renal function to determine the relationship between ET-1 and glomerular size and Palb that may contribute to hyperfiltration in humanized sickle cell (HbSS) and control (HbAA) mice at 8-32 weeks of age. HbSS mice were characterized by significant increases in plasma and glomerular ET-1 expression in both sexes although this increase was significantly greater in males. HbSS glomeruli of both males and females presented with a progressive and significant increase in glomerular size, volume, and Kf During the onset of hyperfiltration, plasma and glomerular ET-1 expression were associated with a greater increase in glomerular size and Kf in HbSS mice, regardless of sex. The pattern of Palb augmentation during the hyperfiltration was also associated with an increase in glomerular ET-1 expression, in both male and female HbSS mice. However, the increase in Palb was significantly greater in males and delayed in time in females. Additionally, selective endothelin A receptor (ETA) antagonist prevented hyperfiltration in HbSS, regardless of sex. These results suggest that marked sex disparity in glomerular hyperfiltration may be driven, in part, by ET-1-dependent ultra-structural changes in filtration barrier components contributing to glomerular hyperfiltration in HbSS mice.


Assuntos
Anemia Falciforme/metabolismo , Endotelina-1/metabolismo , Taxa de Filtração Glomerular , Nefropatias/metabolismo , Glomérulos Renais/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/patologia , Anemia Falciforme/fisiopatologia , Animais , Modelos Animais de Doenças , Antagonistas do Receptor de Endotelina A/farmacologia , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Hemoglobina A/genética , Hemoglobinas/genética , Humanos , Nefropatias/etiologia , Nefropatias/patologia , Nefropatias/fisiopatologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Glomérulos Renais/fisiopatologia , Masculino , Camundongos Transgênicos , Mutação , Fenilpropionatos/farmacologia , Piridazinas/farmacologia , Fatores de Risco , Fatores Sexuais , Transdução de Sinais
18.
PLoS One ; 14(6): e0219047, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31251783

RESUMO

BACKGROUND: The implication of lymphocytes in sickle cell disease pathogenesis is supported by a number of recent reports. These studies provided evidence for the activation of invariant natural killer T (iNKT) cells in adult patients, but did not investigate the involvement of other innate-like T cell subsets so far. METHODS: Here we present a monocentric prospective observational study evaluating the number and functional properties of both circulating conventional and innate-like T cells, namely iNKT, Mucosal-Associated Invariant T (MAIT) and gammadelta (γδ) T cells in a cohort of 39 children with sickle cell disease. RESULTS: Relative to age-matched healthy controls, we found that patients had a higher frequency of IL-13- and IL-17-producing CD4+ T cells, as well as higher MAIT cell counts with an increased frequency of IL-17-producing MAIT cells. Patients also presented increased Vδ2 γδ T cell counts, especially during vaso-occlusive crisis, and a lower frequency of IFNγ-producing Vδ2 γδ T cells, except during crisis. iNKT cell counts and the frequency of IFNγ-producing iNKT cells were unchanged compared to controls. Our study revealed positive correlations between 1) the frequency of IFNγ-producing CD4+, CD8+ and Vδ2 γδ T cells and the number of hospitalizations for vaso-occlusive crisis in the previous year; 2) the frequency of IFNγ-producing iNKT cells and patients' age and 3) the frequency of IL-17-producing Vδ2 γδ T cells and hemoglobin S level. CONCLUSION: These results strongly suggest a role of innate-like T cells in sickle cell disease pathophysiology, especially that of IL-17-producing MAIT and γδ T cells.


Assuntos
Anemia Falciforme/imunologia , Imunidade Inata/imunologia , Células T Invariáveis Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Subpopulações de Linfócitos T/imunologia , Adolescente , Anemia Falciforme/metabolismo , Criança , Feminino , Humanos , Masculino , Células T Invariáveis Associadas à Mucosa/metabolismo , Células T Matadoras Naturais/metabolismo , Estudos Prospectivos , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/metabolismo
19.
Orphanet J Rare Dis ; 14(1): 120, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146777

RESUMO

Sickle cell disease (SCD) is an inherited red blood cell disorder caused by a structural abnormality of hemoglobin called sickle hemoglobin (HbS). Clinical manifestations of SCD are mainly characterized by chronic hemolysis and acute vaso-occlusive crisis, which are responsible for severe acute and chronic organ damage. SCD is widespread in sub-Saharan Africa, in the Middle East, Indian subcontinent, and some Mediterranean regions. With voluntary population migrations, people harboring the HbS gene have spread globally. In 2006, the World Health Organization recognized hemoglobinopathies, including SCD, as a global public health problem and urged national health systems worldwide to design and establish programs for the prevention and management of SCD. Herein we describe the historical experience of the network of hemoglobinopathy centers and their approach to SCD in Italy, a country where hemoglobinopathies have a high prevalence and where SCD, associated with different genotypes including ß-thalassemia, is present in the native population.


Assuntos
Anemia Falciforme/prevenção & controle , Gerenciamento Clínico , Anemia Falciforme/diagnóstico , Anemia Falciforme/metabolismo , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/metabolismo , Doenças Hematológicas/prevenção & controle , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/metabolismo , Hemoglobinopatias/prevenção & controle , Humanos , Hidroxiureia/metabolismo , Itália , Saúde Pública
20.
Neurosci Lett ; 706: 56-60, 2019 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31051220

RESUMO

Pain is the most characteristic feature of sickle cell disease (SCD). Patients with SCD live with unpredictable, recurrent episodes of acute painful crisis, as well as chronic unremitting pain throughout their lifetime. While most of the research and medical efforts have focused on treating vaso-occlusion crisis and acute pain, chronic pain remains a significant challenge faced by patients and physicians. Emerging evidence from human and animal studies has suggested the presence of a neuropathic component in SCD pain. New knowledge on the neurobiology of chronic pain in SCD has significant implications in unraveling the underlying mechanisms. This review focuses on the recent advances on the role of protein kinase C or PKC in promoting and maintaining chronic pain conditions. With a highlight of a specific PKC isoform, PKCδ, we aim to propose PKC as an essential regulator of chronic pain in SCD, which may ultimately lead to innovative therapeutic strategies for treating this devastating life-long problem in patients with SCD.


Assuntos
Anemia Falciforme/metabolismo , Dor Crônica/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Fosforilação
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