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1.
Sci Rep ; 14(1): 276, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168584

RESUMO

Sickle cell disease (SCD) affects millions worldwide, yet there are few therapeutic options. To develop effective treatments, preclinical models that recapitulate human physiology and SCD pathophysiology are needed. SCD arises from a single Glu-to-Val substitution at position 6 in the ß subunit of hemoglobin (Hb), promoting Hb polymerization and subsequent disease. Sheep share important physiological and developmental characteristics with humans, including the same developmental pattern of fetal to adult Hb switching. Herein, we investigated whether introducing the SCD mutation into the sheep ß-globin locus would recapitulate SCD's complex pathophysiology by generating high quality SWISS-MODEL sheep Hb structures and performing MD simulations of normal/sickle human (huHbA/huHbS) and sheep (shHbB/shHbS) Hb, establishing how accurately shHbS mimics huHbS behavior. shHbS, like huHbS, remained stable with low RMSD, while huHbA and shHbB had higher and fluctuating RMSD. shHbB and shHbS also behaved identically to huHbA and huHbS with respect to ß2-Glu6 and ß1-Asp73 (ß1-Asn72 in sheep) solvent interactions. These data demonstrate that introducing the single SCD-causing Glu-to-Val substitution into sheep ß-globin causes alterations consistent with the Hb polymerization that drives RBC sickling, supporting the development of a SCD sheep model to pave the way for alternative cures for this debilitating, globally impactful disease.


Assuntos
Anemia Falciforme , Hemoglobinas , Adulto , Humanos , Animais , Ovinos , Hemoglobinas/genética , Anemia Falciforme/terapia , Hemoglobina A , Globinas beta/genética , Modelos Animais , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/química
2.
Biomed Chromatogr ; 38(3): e5799, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041149

RESUMO

The management of life-threatening complications in patients with sickle cell disease (SCD) requires an accurate and reproducible quantification of haemoglobin A (HbA) and S (HbS) with a short turnaround time and 24-7 availability. We propose a novel method for quantifying HbA and HbS using the glycated haemoglobin (HbA1c) assay on a Tosoh HLC-723G8 (G8) analyser in variant mode. HbA and HbS results obtained using our method highly correlated with results obtained using a reference method (r > 0.99 for 124 samples of patients with SCD or sickle cell trait). Our method met laboratory requirements for linearity (coefficient of variation [CV] and bias <5%), between-run and within-run reproducibility (CV <10%) and carryover (<0.5%) over the range of HbS and HbA values expected in a therapeutic context. Using the G8 analyser in variant mode is viable for monitoring HbA and HbS concentrations in dire situations. This method is easy to use, quick (1.6 min per sample), and automatable and produces highly reproducible results without significant bias. Finally, it does not require modifications to the analytical pipeline recommended by the supplier, enabling a 24-7 availability without disrupting routine monitoring of HbA1c in the laboratory.


Assuntos
Anemia Falciforme , Hemoglobina A , Hemoglobina Falciforme , Humanos , Hemoglobinas Glicadas , Reprodutibilidade dos Testes
3.
Clin Chem Lab Med ; 62(4): 753-761, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37870921

RESUMO

OBJECTIVES: The escalating prevalence of diabetes worldwide has resulted in a dramatic increase in the number of people who need testing, which in turn necessitates faster HbA1c measurement. The Tosoh GR01 addresses the need for fast turnaround times of whilst offering pragmatic steps to maintain result accuracy in a single instrument by offering two distinct operating modes: Short Mode (SM) and Long Mode (LM). The aim of this study was to evaluate all relevant aspects of the performance of the Tosoh GR01 with a view to accepting the instrument as a future Secondary Reference Measurement Procedure (SRMP) for the IFCC. METHODS: Certified Clinical & Laboratory Standards Institute (CLSI) Evaluation Protocols (EP) were used to evaluate precision (EP-5), accuracy (EP-9), linearity (EP-6), carry-over (EP-10) and the effect of hemoglobin variants and other potential interferences. RESULTS: Both modes demonstrated CVs <0.6 % in SI units and <0.4 % in NGSP units at 46 mmol/mol (6.4 %) and 75 mmol/mol (9.0 %) and passed both National Glycohemoglobin Standardization Program (NGSP) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) certification procedures when compared with 7 IFCC Certified Secondary Reference Measurement Procedures (SRMP). Sigma for both modes was >6 when using the results of EP-5 and EP-9 at an HbA1c concentration of 50 mmol/mol (6.7 %). Neither mode showed any interference with common Hb-variants except for HbAE when HbA1c was >65 mmol/mol. In the SM HbAS, HbAD and HbAC were recognized but no result was reported. CONCLUSIONS: There is a good balance between speed and accuracy for determining HbA1c with the Tosoh GR01 in both analytical modes and the device is suitable for use as an IFCC SRMP.


Assuntos
Diabetes Mellitus , Hemoglobina A , Humanos , Hemoglobinas Glicadas , Diabetes Mellitus/diagnóstico , Padrões de Referência , Laboratórios
4.
Clin Chem Lab Med ; 62(3): 453-463, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-37845805

RESUMO

OBJECTIVES: Accurate quantification of hemoglobin (Hb) A2 is vital for diagnosing ß-thalassemia carriers. This study aimed to assess the precision and diagnostic utility of HbA2 measurements using the new high-performance liquid chromatography (HPLC) method, Premier Resolution, in comparison to capillary electrophoresis (CE). METHODS: We analyzed 418 samples, previously identified as A2A by CE, using Premier Resolution-HPLC. We compared the results, established correlations, and determined an optimal HbA2 cutoff value for ß-thalassemia screening. Additionally, we prospectively evaluated the chosen cutoff value in 632 samples. Mutations in the ß- and α-globin genes were identified using polymerase chain reaction (PCR) techniques and DNA sequencing. RESULTS: HbA2 levels were consistently higher with Premier Resolution, yet there was a significant correlation with CE in all samples (bias, -0.33; r, 0.991), ß-thalassemia (bias, -0.27; r, 0.927), and non-ß-thalassemia carriers (bias, -0.36; r, 0.928). An HbA2 cutoff value of ≥4.0 % for ß-thalassemia screening achieved 100 % sensitivity and 99.6 % specificity. Further validation yielded sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 97.3 , 99.8, 97.3, 99.8, and 99.7 %, respectively. We also identified a rare ß-Hb variant, Hb La Desirade [HBB:c.389C>T], associated with ß-thalassemia and co-inherited with a single α-globin gene. CONCLUSIONS: The Premier Resolution HPLC is a reliable and accurate method for routine ß-thalassemia carrier screening, aligning with existing CE methods.


Assuntos
Hemoglobina Falciforme , Talassemia beta , Humanos , Talassemia beta/diagnóstico , Talassemia beta/genética , Hemoglobina A/análise , Reprodutibilidade dos Testes , Hemoglobina A2/genética , Hemoglobina A2/análise , Mutação , alfa-Globinas/genética
7.
J Agric Food Chem ; 71(49): 19717-19726, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38029278

RESUMO

Meleagris gallopavo (turkey) coexpresses distinct hemoglobin (Hb) isoforms, Hb α2Aß2 (HbA) and α2Dß2 (HbD), at a ratio of ∼3:1 (HbA:HbD). Herein, the reactivities of HbA and HbD were investigated in their native and free fatty acid (FFA)-modified states. Results indicated that HbD displays elevated autoxidation (kox) and an increased propensity to oxidize lipids in its reduced (oxy) and oxidized (met) forms. Interestingly, metHbD displayed less heme-globin cross-linking compared to HbA. Regarding FFA-modified Hb, we found that an FFA mixture and linoleic acid (LA) produced a bis-histidyl ferric (Bis-His) Hb species, decreasing the ability of Hb to oxidize lipids. Using molecular docking, we found LA to hydrogen bond with ß Arg C6, found at the α1ß2 interface, but the extent of Bis-His formation differs between HbA and HbD. Our findings suggest HbA displays elevated oxidative stability compared to HbD and that FFA may act as allosteric effectors of metHb.


Assuntos
Ácidos Graxos , Hemoglobina A , Hemoglobina A/química , Simulação de Acoplamento Molecular , Hemoglobinas/química , Isoformas de Proteínas
8.
Lancet Healthy Longev ; 4(7): e337-e344, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37421961

RESUMO

BACKGROUND: Metformin, a first-line medication for type 2 diabetes, might also have a protective effect against ageing-related diseases, but so far little experimental evidence is available. We sought to assess the target-specific effect of metformin on biomarkers of ageing in the UK Biobank. METHODS: In this drug target mendelian randomisation study, we assessed the target-specific effect of four putative targets of metformin (AMPK, ETFDH, GPD1, and PEN2), involving ten genes. Genetic variants with evidence of causation of gene expression, glycated haemoglobin A1c (HbA1c), and colocalisation were used as instruments mimicking the target-specific effect of metformin via HbA1c lowering. The biomarkers of ageing considered were phenotypic age (PhenoAge) and leukocyte telomere length. To triangulate the evidence, we also assessed the effect of HbA1c on the outcomes using a polygenic mendelian randomisation design and assessed the effect of metformin use on these outcomes using a cross-sectional observational design. FINDINGS: GPD1-induced HbA1c lowering was associated with younger PhenoAge (ß -5·26, 95% CI -6·69 to -3·83) and longer leukocyte telomere length (ß 0·28, 0·03 to 0·53), and AMPKγ2 (PRKAG2)-induced HbA1c lowering was associated with younger PhenoAge (ß -4·88, -7·14 to -2·62) but not with longer leukocyte telomere length. Genetically predicted HbA1c lowering was associated with younger PhenoAge (ß -0·96 per SD lowering of HbA1c, 95% CI -1·19 to -0·74) but not associated with leukocyte telomere length. In the propensity score matched analysis, metformin use was associated with younger PhenoAge (ß -0·36, 95% CI -0·59 to -0·13) but not with leukocyte telomere length. INTERPRETATION: This study provides genetic validation evidence that metformin might promote healthy ageing via targets GPD1 and AMPKγ2 (PRKAG2), and the effect could be in part due to its glycaemic property. Our findings support further clinical research into metformin and longevity. FUNDING: Healthy Longevity Catalyst Award, National Academy of Medicine, and Seed Fund for Basic Research, The University of Hong Kong.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Bancos de Espécimes Biológicos , Estudos Transversais , Biomarcadores , Hemoglobina A/genética , Fatores de Transcrição/genética , Fatores de Transcrição/uso terapêutico , Telômero/genética , Telômero/metabolismo , Reino Unido
9.
Hematology ; 28(1): 2213043, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37183964

RESUMO

BACKGROUND: Neonatal screening is the first action necessary to identify children with sickle cell disease (SCD) and thus ensure their care. Using rapid tests to give an immediate result to families is a new resilient approach of great interest. These two aspects are essential for establishing an adequate health policy for this disease. This study was undertaken in Kisangani to update the current incidence of neonatal SCD. METHODS: Heel prick blood samples of 1432 babies born from different racial groups of parents living in Kisangani were collected at birth and screened using a point of care test, i.e. the HemoTypeSCTM. RESULTS: The incidence at birth was 2.2% (n = 31; 95% CI: [1.5%-3.1%]) for HbSS homozygosity and 21% (n = 303; 95% CI: [19%-23%]) for HbAS heterozygosity. Compared to a previous study in 2010; the incidence at the birth of the HbSS form has doubled, while that of the heterozygous form HbAS remained almost unchanged. The inter-ethnic incidence of HbSS among the five top-represented ethnic groups was significant (<0.001). CONCLUSION: The prevalence of homozygote form has doubled compared to the 0.96% reported in 2010. Setting up a neonatal screening program and an awareness unit is necessary to assess the need for care services correctly.


Assuntos
Anemia Falciforme , Triagem Neonatal , Lactente , Recém-Nascido , Criança , Humanos , República Democrática do Congo/epidemiologia , Anemia Falciforme/diagnóstico , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Hemoglobina Falciforme/genética , Testes Imediatos , Hemoglobina A
10.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108709

RESUMO

Malaria affects a significant portion of the global population, with 247 million cases in 2021, primarily in Africa. However, certain hemoglobinopathies, such as sickle cell trait (SCT), have been linked to lower mortality rates in malaria patients. Hemoglobin (Hb) mutations, including HbS and HbC, can cause sickle cell disease (SCD) when both alleles are inherited (HbSS and HbSC). In SCT, one allele is inherited and paired with a normal allele (HbAS, HbAC). The high prevalence of these alleles in Africa may be attributed to their protective effect against malaria. Biomarkers are crucial for SCD and malaria diagnosis and prognosis. Studies indicate that miRNAs, specifically miR-451a and let-7i-5p, are differentially expressed in HbSS and HbAS compared to controls. Our research examined the levels of exosomal miR-451a and let-7i-5p in red blood cells (RBCs) and infected red blood cells (iRBCs) from multiple sickle Hb genotypes and their impact on parasite growth. We assessed exosomal miR-451a and let-7i-5p levels in vitro in RBC and iRBC supernatants. Exosomal miRNAs exhibited distinct expression patterns in iRBCs from individuals with different sickle Hb genotypes. Additionally, we discovered a correlation between let-7i-5p levels and trophozoite count. Exosomal miR-451a and let-7i-5p could modulate SCD and malaria severity and serve as potential biomarkers for malaria vaccines and therapies.


Assuntos
Anemia Falciforme , Malária , MicroRNAs , Parasitos , Traço Falciforme , Animais , Humanos , Parasitos/metabolismo , Hemoglobinas/metabolismo , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , MicroRNAs/genética , Genótipo , Anemia Falciforme/genética , Traço Falciforme/genética , Biomarcadores , Hemoglobina A/genética , Malária/genética
11.
J Diabetes Investig ; 14(3): 494-497, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36625083

RESUMO

The presence of hemoglobin (Hb) variants might interfere with some glycated hemoglobin (HbA1c ) measurements. There have been a few reports of compound Hb variants affecting HbA1c testing. Here, we report a case of the coinheritance of two Hb variants in the ß-globin gene. High-performance liquid chromatography with the Hb program showed a high HbA2 level. Similarly, an E-window peak was separated on the high-performance liquid chromatography with a glycated Hb program. However, capillary electrophoresis showed two abnormal peaks and no HbA peak. Sanger sequencing confirmed the presence of Hb New York and HbE. This is the first report of a compound heterozygote for HbE and Hb New York. The double heterozygote caused erroneous results for HbA1c on high-performance liquid chromatography and enzyme assay.


Assuntos
Hemoglobina E , Hemoglobinas Anormais , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Hemoglobinas Glicadas/genética , Hemoglobina E/análise , Hemoglobina E/genética , Hemoglobinas Anormais/genética , Hemoglobinas Anormais/análise , Hemoglobinas Anormais/química , Heterozigoto , Hemoglobina A
12.
J Pediatr Hematol Oncol ; 45(5): 241-246, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35972997

RESUMO

BACKGROUND: Current guidelines recommend a preoperative hemoglobin of 10.0 g/dL in patients with sickle cell disease [SCD], however, this threshold continues to be an area of controversy. Previous studies demonstrating the benefits of preoperative transfusions have largely not captured patients with elevated baseline hemoglobin, in part due to low hydroxyurea uptake and exclusion of nonhemoglobin SS SCD. MATERIALS AND METHODS: We conducted a retrospective chart review of patients with SCD <18 years of age undergoing low and medium-risk procedures at 2 academic medical centers in Canada between 2007 and 2017. The primary objective was to study the association of preoperative transfusion on postoperative complications in patients with SCD with baseline hemoglobin between 9.0 and 10.0 g/dL. Multivariable logistic regression was used to estimate the adjusted effect of preoperative transfusion on the risk of developing postoperative complications. RESULTS: In all, 159 procedures in patients with hemoglobin <9.0 g/dL [Hb <9.0 ] and 173 procedures in patients with hemoglobin between 9.0 and 10.0 g/dL [Hb 9.0-10.0 ] were analyzed. In the absence of preoperative transfusion, Hb 9.0-10.0 patients had lower overall complications [23% vs. 34%] compared with Hb <9.0 patients [OR 0.29, 95% CI 0.12-0.72, P =0.008]. In total, 75% of Hb <9.0 and 21% of Hb 9.0-10.0 patients received a preoperative simple transfusion. Transfusion was associated with increased risk of postoperative complications in Hb 9.0-10.0 [OR 3.02, 95% CI 1.26-7.23, P =0.013], but not Hb <9.0 patients [OR 0.64, 95% CI 0.28-1.45, P =0.30]. CONCLUSIONS: Simple transfusion may not be warranted in Hb 9.0-10.0 patients undergoing low-risk procedures. Prospective studies validating these findings are needed.


Assuntos
Anemia Falciforme , Hemoglobinas Anormais , Humanos , Estudos Retrospectivos , Hemoglobina A , Estudos Prospectivos , Transfusão de Eritrócitos/efeitos adversos , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Complicações Pós-Operatórias/etiologia
13.
Ann Clin Biochem ; 60(2): 81-85, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36214153

RESUMO

BACKGROUND: Deletions in the ß-globin cluster are uncommon and cause thalassemia (thal) with hereditary persistence of fetal hemoglobin. They constitute a heterogenous group of disorders characterized by absent or reduced synthesis of adult hemoglobin (Hb A) and increased synthesis of fetal hemoglobin (Hb F). Although the clinical severity of these disorders are asymptomatic owing to the increased Hb F levels, the molecular basis is very heterogenous due to the large deletions in the ß-globin cluster spanning both HBD and HBB genes. Here, we describe a Tunisian family carrying a novel deletion mutation causing (δß)°-thalassemia. METHODS: The amounts of hemoglobin fractions were measured by capillary electrophoresis of hemoglobin. Amplification and sequencing of different regions on the ß-gene cluster were performed by Sanger method. RESULTS: Family study and genetic analysis revealed a large deletion mutation in the ß-globin cluster of 14.5 kb (NG_000,007.3:g. 58,253 to g.72837del14584) at the homozygous state in the patient and at heterozygous state at the other members of the family. This deletion removes the HBD and HBB genes. CONCLUSIONS: In our knowledge, this new large deletion is described for the first time in the Tunisian population and in the world, designed Tunisian(δß)0 in Ithanet database (IthaID: 3971). Therefore, it is important to identify the deletion leading to δß-thalassemia carriers at the molecular level, to highlight the importance of recognizing the clinical features and implementing appropriate testing to clarify the diagnosis and manage the condition.


Assuntos
Hemoglobinas , Talassemia , Globinas beta , Adulto , Humanos , Globinas beta/genética , Globinas beta/análise , Talassemia beta/genética , Proteínas de Transporte , Talassemia delta/sangue , Talassemia delta/genética , Hemoglobina Fetal/genética , Hemoglobina Fetal/análise , Hemoglobina A/análise , Hemoglobina A/genética , Hemoglobinas/análise , Hemoglobinas/genética , Homozigoto , Deleção de Sequência , Talassemia/sangue , Talassemia/genética , Tunísia
14.
J Pharm Biomed Anal ; 223: 115152, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36399908

RESUMO

Aromatic aldehydes act as allosteric effectors of hemoglobin (AEH), forming Schiff-base adducts with the protein to increase its oxygen (O2) affinity; a desirable property in sickle cell disease (SCD) treatment, as the high-O2 affinity hemoglobin (Hb) does not polymerize and subsequently prevents erythrocytes sickling. This study reports the development, validation, and application of a weak cation-exchange HPLC assay - quantifying the appearance of Hb-AEH adduct - as a "universal" method, allowing for the prioritization of AEH candidates through an understanding of their Hb binding affinity and kinetics. Concentration- and time-dependent Hb binding profiles of ten AEHs were determined with HPLC, followed by the appropriate non-linear modeling to characterize their steady-state binding affinity (KDss), and binding kinetics second-order association (kon) and first-order dissociation (koff) rate constants. Vanillin-derived AEHs exhibited enhanced binding affinity to Hb, primarily due to their faster kon. Across AEH, kon and koff values are strongly correlated (r = 0.993, n = 7), suggesting that modifications of the AEH scaffold enhanced their interactions with Hb as intended, but inadvertently increased their Hb-AEH adduct dissociation. To our knowledge, the present study is the first to provide valuable insight into Hb binding kinetics of antisickling aromatic aldehydes, and the assay will be a useful platform in screening/prioritizing drug candidates for SCD treatment.


Assuntos
Aldeídos , Hemoglobina A , Cromatografia Líquida de Alta Pressão , Bases de Schiff , Oxigênio
15.
PLoS One ; 17(12): e0278417, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36454779

RESUMO

The mechanism underlying allostery in hemoglobin (Hb) is still not completely understood. Various models describing the action of allosteric effectors on Hb function have been published in the literature. It has also been reported that some allosteric effectors-such as chloride ions, inositol hexaphosphate, 2,3-diphospho-glycerate and bezafibrate-considerably lower the oxygen affinity of Hb. In this context, an important question is the extent to which these changes influence the conformational dynamics of the protein. Earlier, we elaborated a challenging method based on phosphorescence quenching, which makes characterizing protein-internal dynamics possible in the ms time range. The experimental technique involves phosphorescence lifetime measurements in thermal equilibrium at varied temperatures from 10 K up to 273 K, based on the signal of Zn-protoporphyrin substituted for the heme in the ß-subunits of Hb. The thermal activation of protein dynamics was observed by the enhancement of phosphorescence quenching attributed to O2 diffusion. It was shown that the thermal activation of protein matrix dynamics was clearly distinguishable from the dynamic activation of the aqueous solvent, and was therefore highly specific for the protein. In the present work, the same method was used to study the changes in the parameters of the dynamic activation of human HbA induced by binding allosteric effectors. We interpreted the phenomenon as phase transition between two states. The fitting of this model to lifetime data yielded the change of energy and entropy in the activation process and the quenching rate in the dynamically activated state. The fitted parameters were particularly sensitive to the presence of allosteric effectors and could be interpreted in line with results from earlier experimental studies. The results suggest that allosteric effectors are tightly coupled to the dynamics of the whole protein, and thus underline the importance of global dynamics in the regulation of Hb function.


Assuntos
Hemoglobina A , Radiação , Humanos , Bezafibrato , Entropia , Heme
16.
Hematology ; 27(1): 1003-1009, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36117408

RESUMO

BACKGROUND: Besides the traditional roles of HBA1 and HBB, recent findings suggest that hemoglobin genes may have roles in other contexts. OBJECTIVE: In the present study, we aim to investigate a possible tumor-suppressor role of HBA1 and HBB in acute myeloid leukemia. METHODS: Quantitative real-time PCR (RT-qPCR) was performed to detect the expression levels of HBA1 and HBB in acute myeloid leukemia patients and AML cell lines. The transfected cells were analyzed for Cell Counting Kit-8 (CCK-8), apoptosis, and cell cycle assay. RESULTS: HBA1 and HBB genes were significantly decreased in acute myeloid leukemia patients and AML cell lines. Furthermore, in vitro approaches showed that overexpression of HBA1 and HBB inhibited proliferation, induced cell apoptosis, and blocked cell cycle process at the G2/M phase in K562 cells. CONCLUSION: Our data indicated that HBA1 and HBB genes may be potential tumor-suppressor genes in acute myeloid leukemia.


Assuntos
Hemoglobina A/genética , Hemoglobinas/genética , Leucemia Mieloide Aguda , Proliferação de Células , Hemoglobinas Glicadas , Humanos , Células K562 , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo
17.
Int J Mol Sci ; 23(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35806451

RESUMO

Sickle cell disease (SCD) is a genetic disorder that affects millions of individuals worldwide. Chronic anemia, hemolysis, and vasculopathy are associated with SCD, and their role has been well characterized. These symptoms stem from hemoglobin (Hb) polymerization, which is the primary event in the molecular pathogenesis of SCD and contributes to erythrocyte or red blood cell (RBC) sickling, stiffness, and vaso-occlusion. The disease is caused by a mutation at the sixth position of the ß-globin gene, coding for sickle Hb (HbS) instead of normal adult Hb (HbA), which under hypoxic conditions polymerizes into rigid fibers to distort the shapes of the RBCs. Only a few therapies are available, with the universal effectiveness of recently approved therapies still being monitored. In this review, we first focus on how sickle RBCs have altered metabolism and then highlight how this understanding reveals potential targets involved in the pathogenesis of the disease, which can be leveraged to create novel therapeutics for SCD.


Assuntos
Anemia Falciforme , Doenças Vasculares , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/genética , Descoberta de Drogas , Eritrócitos Anormais/metabolismo , Eritrócitos Anormais/patologia , Hemoglobina A/metabolismo , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Humanos , Doenças Vasculares/etiologia
18.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806029

RESUMO

The hemoglobin switch from fetal (HbF) to adult (HbA) has been studied intensively as an essential model for gene expression regulation, but also as a beneficial therapeutic approach for ß-hemoglobinopathies, towards the objective of reactivating HbF. The transcription factor LRF (Leukemia/lymphoma-related), encoded from the ZBTB7A gene has been implicated in fetal hemoglobin silencing, though has a wide range of functions that have not been fully clarified. We thus established the LRF/ZBTB7A-overexpressing and ZBTB7A-knockdown K562 (human erythroleukemia cell line) clones to assess fetal vs. adult hemoglobin production pre- and post-induction. Transgenic K562 clones were further developed and studied under the influence of epigenetic chromatin regulators, such as DNA methyl transferase 3 (DNMT3) and Histone Deacetylase 1 (HDAC1), to evaluate LRF's potential disturbance upon the aberrant epigenetic background and provide valuable information of the preferable epigenetic frame, in which LRF unfolds its action on the ß-type globin's expression. The ChIP-seq analysis demonstrated that LRF binds to γ-globin genes (HBG2/1) and apparently associates BCL11A for their silencing, but also during erythropoiesis induction, LRF binds the BGLT3 gene, promoting BGLT3-lncRNA production through the γ-δ intergenic region of ß-type globin's locus, triggering the transcriptional events from γ- to ß-globin switch. Our findings are supported by an up-to-date looping model, which highlights chromatin alterations during erythropoiesis at late stages of gestation, to establish an "open" chromatin conformation across the γ-δ intergenic region and accomplish ß-globin expression and hemoglobin switch.


Assuntos
RNA Longo não Codificante , Fatores de Transcrição , Adulto , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , DNA Intergênico/genética , DNA Intergênico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Hemoglobina A/genética , Hemoglobina A/metabolismo , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Globinas beta/genética , Globinas beta/metabolismo , gama-Globinas/genética , gama-Globinas/metabolismo
20.
Cancer Res Commun ; 2(7): 653-662, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36712480

RESUMO

Self-reported type 2 diabetes mellitus (T2DM) is a risk factor for many cancers, suggesting its pathology relates to carcinogenesis. We conducted a case-cohort study to examine associations of hemoglobin A1c (HbA1c) and c-peptide with cancers associated with self-reported T2DM. This study was drawn from a prospective cohort of 32,383 women and men who provided blood specimens at baseline: c-peptide and HbA1c were assessed in 3,000 randomly selected participants who were cancer-free-at-baseline and an additional 2,281 participants who were cancer-free-at-baseline and subsequently diagnosed with incident colorectal, liver, pancreatic, female breast, endometrial, ovarian, bladder, or kidney cancers. Weighted-Cox regression models estimated hazards ratios (HRs) and 95% confidence intervals (CI), adjusted for covariates. C-peptide was associated with higher risk of liver cancer (per standard deviation (SD) HR: 1.80; 95%CI: 1.32-2.46). HbA1c was associated with higher risk of pancreatic cancer (per SD HR: 1.21 95%CI 1.05-1.40) and with some suggestion of higher risks for all-cancers-of-interest (per SD HR: 1.05; 95%CI: 0.99-1.11) and colorectal (per SD HR: 1.09; 95%CI: 0.98-1.20), ovarian (per SD HR: 1.18; 95%CI 0.96-1.45) and bladder (per SD HR: 1.08; 95%CI 0.96-1.21) cancers. Compared to no self-reported T2DM and HbA1c <6.5% (reference group), self-reported T2DM and HbA1c <6.5% (i.e., T2DM in good glycemic control) was not associated with risk of colorectal cancer, whereas it was associated with higher risks of all-cancers-of-interest combined (HR: 1.28; 95%CI: 1.01-1.62), especially for breast and endometrial cancers. Additional large, prospective studies are needed to further explore the roles of hyperglycemia, hyperinsulinemia, and related metabolic traits with T2DM-associated cancers to better understand the mechanisms underlying the self-reported T2DM-cancer association and to identify persons at higher cancer risk.


Assuntos
Neoplasias Colorretais , Diabetes Mellitus Tipo 2 , Neoplasias Hepáticas , Feminino , Humanos , Masculino , Peptídeo C , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas , Neoplasias Hepáticas/complicações , Hemoglobina A
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