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1.
Nucl Med Commun ; 45(8): 658-665, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38832440

RESUMO

OBJECTIVES: In this study, we aim to evaluate the long-term impact of thalassaemia on bone mineral density (BMD) through sequential analysis, compare changes in BMD values between male and female patients and find any correlation between BMD and biochemical markers in the adult thalassaemia group. BMD is a bone mineral density test using dual-energy X-ray to measure calcium hydroxyapatite per unit of bone, reflecting bone strength. METHODS: We conducted a longitudinal retrospective observational cohort study to determine the changes in BMD values and biochemical parameters in adult thalassaemia patients. BMD was assessed at the lumbar spine (L1-L4) and proximal femora using Hologic's bone dual-energy X-ray absorptiometry. Five serial BMD values were retrieved from electronic records. Biochemical parameters, including serum calcium, phosphorus and 25-hydroxyvitamin D levels, were also assessed. RESULTS: A total of 108 patients (47 males and 61 females; median age: 44 years) with thalassaemia major 71 patients, intermedia 20 patients, haemoglobin E disease 14 patients and thalassaemia-alpha three patients were included. The incidence of low BMD in patients with thalassaemia increased from 64 to 74% over three decades of analysis. Females and thalassaemia major patients had lower hip BMD values and corresponding Z -scores. CONCLUSION: There is a progressive decline in BMD values in adult thalassaemia, which was apparent in female thalassaemia major patients. No changes in biochemical parameters, however, were observed over long-term assessments.


Assuntos
Densidade Óssea , Talassemia , Humanos , Masculino , Feminino , Adulto , Estudos Retrospectivos , Estudos Longitudinais , Talassemia/sangue , Talassemia/diagnóstico por imagem , Talassemia/fisiopatologia , Talassemia/complicações , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Absorciometria de Fóton
2.
Blood Adv ; 8(10): 2433-2441, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38330179

RESUMO

ABSTRACT: Pyruvate kinase (PK) deficiency is a rare, hereditary disease characterized by chronic hemolytic anemia. Iron overload is a common complication regardless of age, genotype, or transfusion history. Mitapivat, an oral, allosteric PK activator, improves anemia and hemolysis in adult patients with PK deficiency. Mitapivat's impact on iron overload and ineffective erythropoiesis was evaluated in adults with PK deficiency who were not regularly transfused in the phase 3 ACTIVATE trial and long-term extension (LTE) (#NCT03548220/#NCT03853798). Patients in the LTE received mitapivat throughout ACTIVATE/LTE (baseline to week 96; mitapivat-to-mitapivat [M/M] arm) or switched from placebo (baseline to week 24) to mitapivat (week 24 to week 96; placebo-to-mitapivat [P/M] arm). Changes from baseline in markers of iron overload and erythropoiesis were assessed to week 96. Improvements in hepcidin (mean, 4770.0 ng/L; 95% confidence interval [CI], -1532.3 to 11 072.3), erythroferrone (mean, -9834.9 ng/L; 95% CI, -14 328.4 to -5341.3), soluble transferrin receptor (mean, -56.0 nmol/L; 95% CI, -84.8 to -27.2), and erythropoietin (mean, -32.85 IU/L; 95% CI, -54.65 to -11.06) were observed in the M/M arm (n = 40) from baseline to week 24, sustained to week 96. No improvements were observed in the P/M arm (n = 40) to week 24; however, upon transitioning to mitapivat, improvements similar to those observed in the M/M arm were seen. Mean changes from baseline in liver iron concentration by magnetic resonance imaging at week 96 in the M/M arm and the P/M arm were -2.0 mg Fe/g dry weight (dw; 95% CI, -4.8 to -0.8) and -1.8 mg Fe/g dw (95% CI, -4.4 to 0.80), respectively. Mitapivat is the first disease-modifying pharmacotherapy shown to have beneficial effects on iron overload and ineffective erythropoiesis in patients with PK deficiency. This trial was registered at www.ClinicalTrials.gov as #NCT03548220 (ACTIVATE) and #NCT03853798 (LTE).


Assuntos
Anemia Hemolítica Congênita não Esferocítica , Eritropoese , Sobrecarga de Ferro , Piruvato Quinase , Erros Inatos do Metabolismo dos Piruvatos , Humanos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/tratamento farmacológico , Eritropoese/efeitos dos fármacos , Adulto , Piruvato Quinase/deficiência , Masculino , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Alanina/uso terapêutico , Alanina/análogos & derivados , Piperazinas , Quinolinas
3.
Am J Hematol ; 99(2): 182-192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37782758

RESUMO

Luspatercept, a ligand-trapping fusion protein, binds select TGF-ß superfamily ligands implicated in thalassemic erythropoiesis, promoting late-stage erythroid maturation. Luspatercept reduced transfusion burden in the BELIEVE trial (NCT02604433) of 336 adults with transfusion-dependent thalassemia (TDT). Analysis of biomarkers in BELIEVE offers novel physiological and clinical insights into benefits offered by luspatercept. Transfusion iron loading rates decreased 20% by 1.4 g (~7 blood units; median iron loading rate difference: -0.05 ± 0.07 mg Fe/kg/day, p< .0001) and serum ferritin (s-ferritin) decreased 19.2% by 269.3 ± 963.7 µg/L (p < .0001), indicating reduced macrophage iron. However, liver iron content (LIC) did not decrease but showed statistically nonsignificant increases from 5.3 to 6.7 mg/g dw. Erythropoietin, growth differentiation factor 15, soluble transferrin receptor 1 (sTfR1), and reticulocytes rose by 93%, 59%, 66%, and 112%, respectively; accordingly, erythroferrone increased by 51% and hepcidin decreased by 53% (all p < .0001). Decreased transfusion with luspatercept in patients with TDT was associated with increased erythropoietic markers and decreasing hepcidin. Furthermore, s-ferritin reduction associated with increased erythroid iron incorporation (marked by sTfR1) allowed increased erythrocyte marrow output, consequently reducing transfusion needs and enhancing rerouting of hemolysis (heme) iron and non-transferrin-bound iron to the liver. LIC increased in patients with intact spleens, consistent with iron redistribution given the hepcidin reduction. Thus, erythropoietic and hepcidin changes with luspatercept in TDT lower transfusion dependency and may redistribute iron from macrophages to hepatocytes, necessitating the use of concomitant chelator cover for effective iron management.


Assuntos
Receptores de Activinas Tipo II , Fragmentos Fc das Imunoglobulinas , Ferro , Proteínas Recombinantes de Fusão , Talassemia , Adulto , Humanos , Hepcidinas , Eritropoese/fisiologia , Talassemia/complicações , Receptores da Transferrina , Ferritinas
4.
Am J Hematol ; 98(9): 1425-1435, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37497888

RESUMO

SLN124, an N-acetylgalactosamine conjugated 19-mer short interfering RNA, is being developed to treat iron-loading anemias (including beta-thalassemia and myelodysplastic syndromes) and myeloproliferative neoplasms (polycythemia vera). Through hepatic targeting and silencing of the TMPRSS6 gene, SLN124 increases endogenous hepcidin synthesis. This is the first clinical report of an siRNA targeting a component of iron homeostasis. This first-in-human, phase 1 study assessed the safety, tolerability, pharmacokinetics, and pharmacodynamics of single ascending doses of SLN124 (1.0, 3.0, and 4.5 mg/kg) in healthy volunteers. Twenty-four participants were randomized in three sequential cohorts of eight subjects, each to receive a single dose of either SLN124 or placebo (6:2 randomization), administered subcutaneously. There were no serious or severe adverse events, or discontinuations due to adverse events, and most treatment-emergent adverse events were mild, including transient mild injection site reactions, resolving without intervention. SLN124 was rapidly absorbed, with a median tmax of 4-5 h across all treatment groups, and largely eliminated from plasma by 48 h. Plasma concentrations increased in a greater than dose proportional fashion between treatment groups. In all SLN124 groups, a dose-related effect was observed across iron metabolism markers, and across erythroid markers, SLN124 resulted in increased plasma hepcidin levels, peaking around Day 29, and consequent dose-related sustained reductions in plasma iron and transferrin saturation with decreased reticulocyte production, MCHC, and MCV. Results suggest duration of action lasting up to 56 days after a single SLN124 dose, on hepcidin and hematological parameters of iron metabolism (serum iron and TSAT).


Assuntos
Anemia Ferropriva , Ferro , Humanos , Hepcidinas/genética , RNA Interferente Pequeno/genética , Voluntários Saudáveis , Anemia Ferropriva/tratamento farmacológico , Método Duplo-Cego
5.
Eur J Haematol ; 111(1): 113-124, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37095595

RESUMO

BACKGROUND: Patients with transfusion-dependent (TD) ß-thalassemia require long-term red blood cell transfusions (RBCTs) that lead to iron overload, impacting health-related quality of life (HRQoL). METHODS: The impact of luspatercept, a first-in-class erythroid maturation agent, versus placebo on HRQoL of patients with TD ß-thalassemia was evaluated in the phase 3 BELIEVE trial. HRQoL was assessed at baseline and every 12 weeks using the 36-item Short Form Health Survey (SF-36) and Transfusion-dependent Quality of Life questionnaire (TranQol). Mean change in HRQoL was evaluated from baseline to week 48 for patients receiving luspatercept + best supportive care (BSC) and placebo + BSC and between luspatercept responders and non-responders. RESULTS: Through week 48, for both groups, mean scores on SF-36 and TranQol domains were stable over time and did not have a clinically meaningful change. At week 48, more patients who achieved clinical response (≥50% reduction in RBCT burden over 24 weeks) in the luspatercept + BSC group had improvement in SF-36 Physical Function compared with placebo + BSC (27.1% vs. 11.5%; p = .019). CONCLUSIONS: Luspatercept + BSC reduced transfusion burden while maintaining patients' HRQoL. HRQoL domain improvements from baseline through 48 weeks were also enhanced for luspatercept responders.


Assuntos
Talassemia beta , Humanos , Receptores de Activinas Tipo II/uso terapêutico , Talassemia beta/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Qualidade de Vida
7.
Am J Hematol ; 98(3): 533-540, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36565452

RESUMO

Many disorders of iron homeostasis (e.g., iron overload) are associated with the dynamic kinetic profiles of multiple non-transferrin bound iron (NTBI) species, chronic exposure to which is associated with deleterious end-organ effects. Here we discuss the chemical nature of NTBI species, challenges with measuring NTBI in plasma, and the clinical relevance of NTBI exposure based on source (iron overload disorder vs. intravenous iron-carbohydrate complex administration). NTBI is not a single entity but consists of multiple, often poorly characterized species, some of which are kinetically non-exchangeable while others are relatively exchangeable. Prolonged presence of plasma NTBI is associated with excessive tissue iron accumulation in susceptible tissues, with consequences, such as endocrinopathy and heart failure. In contrast, intravenous iron-carbohydrate nanomedicines administration leads only to transient NTBI appearance and lacks evidence for association with adverse clinical outcomes. Assays to measure plasma NTBI are typically technically complex and remain chiefly a research tool. There have been two general approaches to estimating NTBI: capture assays and redox-activity assays. Early assays could not avoid capturing some iron from transferrin, thus overestimating NTBI. By contrast, some later assays may have promoted the donation of NTBI species to transferrin during the assay procedure, potentially underestimating NTBI levels. The levels of transferrin saturation at which NTBI species have been detectable have varied between different methodologies and between patient populations studied.


Assuntos
Sobrecarga de Ferro , Ferro , Humanos , Administração Intravenosa , Relevância Clínica , Ferro/sangue , Ferro/química , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Transferrina/química , Transferrina/metabolismo
9.
Lancet Haematol ; 9(10): e733-e744, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36007538

RESUMO

BACKGROUND: In patients with non-transfusion-dependent ß-thalassaemia, haemoglobin concentrations lower than 10 g/dL are associated with a higher risk of morbidity, mortality, and impaired quality of life. No drugs are specifically approved for anaemia management in patients with non-transfusion-dependent ß-thalassaemia, other than transfusion therapy administered infrequently in accordance with patients' needs. We assessed the efficacy and safety of luspatercept versus placebo in patients with non-transfusion-dependent ß-thalassaemia. METHODS: We did a phase 2, randomised, double-blind, multicentre, placebo-controlled trial in 12 centres in six countries (Thailand [n=1], Lebanon [n=1], Greece [n=2], Italy [n=5], the UK [n=1], and the USA [n=2]). Eligible patients were aged 18 years or older, had confirmed diagnosis of ß-thalassaemia or haemoglobin E/ß-thalassaemia (concomitant α-globin deletion, mutation, or duplication were allowed), and a baseline haemoglobin concentration of 10·0 g/dL or lower. All patients were non-transfusion-dependent. Patients were randomly assigned (2:1) to luspatercept or placebo using an interactive response technology system and stratified by baseline haemoglobin concentration (≥8·5 g/dL vs <8·5 g/dL) and baseline Non-Transfusion-Dependent ß-thalassaemia-Patient-Reported Outcome Tiredness/Weakness domain score (≥3 vs <3). All patients, study site staff, and sponsor representatives (who reviewed the data), except for designated individuals, were masked to drug assignment until the time the study was unblinded. Luspatercept or placebo was given once subcutaneously every 3 weeks for 48 weeks in the double-blind treatment period. Luspatercept was started at 1·0 mg/kg with titration up to 1·25 mg/kg, or reduction in the event of toxicity or excessive haemoglobin concentration increase. The primary endpoint was achievement of an increase from baseline of 1·0 g/dL or higher in mean haemoglobin concentration over a continuous 12-week interval during weeks 13-24, in the absence of transfusions. The primary efficacy and safety analyses were done in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT03342404, and is ongoing. FINDINGS: Between Feb 5, 2018, and Oct 14, 2019, 160 patients were screened for eligiblity, of whom 145 were randomly assigned to luspatercept (n=96) or placebo (n=49). 82 (57%) patients were female and 63 (43%) were male. 44 (30%) patients were Asian, 87 (60%) were White, and 14 (10%) identified as another race. The study met its primary endpoint: 74 (77%) of 96 patients in the luspatercept group and none in the placebo group had an increase of at least 1·0 g/dL in haemoglobin concentration (common risk difference 77·1 [95% CI 68·7-85·5]; p<0·0001). The proportion of patients with serious adverse events was lower in the luspatercept group than in the placebo group (11 [12%] vs 12 [25%]). Treatment-emergent adverse events most commonly reported with luspatercept were bone pain (35 [37%]), headache (29 [30%]), and arthralgia (28 [29%]). No thromboembolic events or deaths were reported during the study. INTERPRETATION: Luspatercept represents a potential treatment for adult patients with non-transfusion-dependent ß-thalassaemia, for whom effective approved treatment options are scarce. FUNDING: Celgene and Acceleron Pharma.


Assuntos
Hemoglobina E , Talassemia beta , Receptores de Activinas Tipo II , Adulto , Método Duplo-Cego , Feminino , Hemoglobina E/uso terapêutico , Humanos , Fragmentos Fc das Imunoglobulinas , Masculino , Qualidade de Vida , Proteínas Recombinantes de Fusão , Resultado do Tratamento , alfa-Globinas , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico
11.
N Engl J Med ; 386(5): 415-427, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34891223

RESUMO

BACKGROUND: Betibeglogene autotemcel (beti-cel) gene therapy for transfusion-dependent ß-thalassemia contains autologous CD34+ hematopoietic stem cells and progenitor cells transduced with the BB305 lentiviral vector encoding the ß-globin (ßA-T87Q) gene. METHODS: In this open-label, phase 3 study, we evaluated the efficacy and safety of beti-cel in adult and pediatric patients with transfusion-dependent ß-thalassemia and a non-ß0/ß0 genotype. Patients underwent myeloablation with busulfan (with doses adjusted on the basis of pharmacokinetic analysis) and received beti-cel intravenously. The primary end point was transfusion independence (i.e., a weighted average hemoglobin level of ≥9 g per deciliter without red-cell transfusions for ≥12 months). RESULTS: A total of 23 patients were enrolled and received treatment, with a median follow-up of 29.5 months (range, 13.0 to 48.2). Transfusion independence occurred in 20 of 22 patients who could be evaluated (91%), including 6 of 7 patients (86%) who were younger than 12 years of age. The average hemoglobin level during transfusion independence was 11.7 g per deciliter (range, 9.5 to 12.8). Twelve months after beti-cel infusion, the median level of gene therapy-derived adult hemoglobin (HbA) with a T87Q amino acid substitution (HbAT87Q) was 8.7 g per deciliter (range, 5.2 to 10.6) in patients who had transfusion independence. The safety profile of beti-cel was consistent with that of busulfan-based myeloablation. Four patients had at least one adverse event that was considered by the investigators to be related or possibly related to beti-cel; all events were nonserious except for thrombocytopenia (in 1 patient). No cases of cancer were observed. CONCLUSIONS: Treatment with beti-cel resulted in a sustained HbAT87Q level and a total hemoglobin level that was high enough to enable transfusion independence in most patients with a non-ß0/ß0 genotype, including those younger than 12 years of age. (Funded by Bluebird Bio; HGB-207 ClinicalTrials.gov number, NCT02906202.).


Assuntos
Produtos Biológicos/uso terapêutico , Terapia Genética/métodos , Globinas beta/genética , Talassemia beta/terapia , Adolescente , Adulto , Produtos Biológicos/efeitos adversos , Bussulfano/uso terapêutico , Criança , Transfusão de Eritrócitos/efeitos adversos , Eritropoese , Feminino , Vetores Genéticos , Genótipo , Hemoglobinas/análise , Humanos , Sobrecarga de Ferro/prevenção & controle , Lentivirus/genética , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Talassemia beta/sangue , Talassemia beta/genética
13.
Front Physiol ; 13: 1053060, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620219

RESUMO

ß-Thalassemia is characterized by ineffective erythropoiesis leading to chronic anemia. Thus, increased iron absorption from the duodenum and via blood transfusions is required to maintain normal blood hemoglobin (Hb) levels and iron chelators in the removal of excessive iron. Certain agents are also needed for the improvement of stress erythropoiesis and iron dysregulation. Green tea extract (GTE), which is rich in epigallocatechin-3-gallate (EGCG), is known to possess radical scavenging and iron-chelating activities. We aimed to assess the effects of green tea extract on erythroid regulators, iron mobilization and anti-lipid peroxidation in the liver, spleen, and kidneys of iron-loaded ß-globin gene knockout thalassemic (BKO) mice. Our results indicate that treatments of green tea extract and/or deferiprone (DFP) diminished levels of plasma erythropoietin (EPO) and erythroferrone (ERFE), and consistently suppressed kidney Epo and spleen Erfe mRNA expressions (p < .05) in iron- loaded BKO mice when compared with untreated mice. Coincidently, the treatments decreased plasma ferritin (Ft) levels, iron content levels in the liver (p < .05), spleen (p < .05), and kidney tissues of iron-loaded BKO mice. Furthermore, lipid-peroxidation products in the tissues and plasma were also decreased when compared with untreated mice. This is the first evidence of the orchestral role of green tea extract abundant with epigallocatechin-3-gallate in improving ineffective erythropoiesis, iron dysregulation and oxidative stress in iron-overloaded ß-thalassemic mice.

14.
Haematologica ; 106(11): 2885-2896, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33054113

RESUMO

Intravenous iron-carbohydrate complex preparations (IVIPs) are non-interchangeable pro-drugs: their pharmacokinetics (PK) varies determined by semi-crystalline iron core and carbohydrate shell structures, influences pharmacodynamics (PD) and thus efficacy and safety. Examining PK/PD relationships of 3 IVIPs we identify a two-pathway model of transient NTBI generation following single dose administration. 28 hypoferremic non-anemic patients randomized to 200mg iron as ferric carboxymaltose (Fe-carboxymaltose), iron sucrose (Fe-sucrose), iron isomaltoside 1000 (Fe-isomaltoside-1000), n=8/arm, or placebo, n=4, on a 2-week PK/PD study, had samples analysed for total serum iron, IVIP-iron, transferrin-bound iron (TBI) by HPLC-ICP-MS, transferrin saturation (TSAT), serum ferritin (s-Ferritin) by standard methods, non-TBI (NTBI) and hepcidin as published before. IVIP-dependent increases in these parameters returned to baseline in 48-150h, except for s-Ferritin and TSAT. NTBI was low with Fe-isomaltoside-1000 (0.13µM at 8h), rapidly increased with Fe-sucrose (0.8µM at 2h, 1.25µM at 4h), and delayed for Fe-carboxymaltose (0.57µM at 24h). NTBI AUCs were 7-fold greater for Fe-carboxymaltose and Fe-sucrose than for Fe-isomaltoside-1000. Hepcidin peak time varied, but not AUC or mean levels. s-Ferritin levels and AUC were highest for Fe-carboxymaltose and greater than placebo for all IVIPs. We propose 2 mechanisms for the observed NTBI kinetics: rapid and delayed NTBI appearance consistent with direct (circulating IVIP-to-plasma) and indirect (IVIP-to-macrophage-to-plasma) iron release based on IVIP plasma half-life and s-Ferritin dynamics. IVIPs generate different, broadly stability- and PK-dependent, NTBI and s-Ferritin signatures, which may influence iron bioavailability, efficacy and safety. Longer-term studies should link NTBI exposure to subsequent safety and efficacy parameters and potential clinical consequences.


Assuntos
Anemia Ferropriva , Hematínicos , Compostos Férricos , Ferritinas , Humanos , Ferro/metabolismo , Transferrina
15.
Molecules ; 26(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375091

RESUMO

Coffee is rich in caffeine (CF), chlorogenic acid (CGA) and phenolics. Differing types of coffee beverages and brewing procedures may result in differences in total phenolic contents (TPC) and biological activities. Inflammation and increases of platelet activation and aggregation can lead to thrombosis. We focused on determining the chemical composition, antioxidant activity and inhibitory effects on agonist-induced platelet aggregation and cyclooxygenase (COX) of coffee beverages in relation to their preparation method. We prepared instant coffee and brewed coffee beverages using drip, espresso, and boiling techniques. Coffee extracts were assayed for their CF and CGA contents using HPLC, TPC using colorimetry, platelet aggregation with an aggregometer, and COX activity using ELISA. The findings have shown all coffee extracts, except the decaffeinated types, contained nearly equal amounts of CF, CGA, and TPC. Inhibitory effects of coffee extracts on platelet aggregation differed depending on the activation pathways induced by different agonists. All espresso, drip and boiled coffee extracts caused dose dependent inhibition of platelet aggregation induced by ADP, collagen, epinephrine, and arachidonic acid (ARA). The most marked inhibition was seen at low doses of collagen or ARA. Espresso and drip extracts inhibited collagen-induced platelet aggregation more than purified caffeine or CGA. Espresso, boiled and drip coffee extracts were also a more potent inhibitors of COX-1 and COX-2 than purified caffeine or CGA. We conclude that inhibition of platelet aggregation and COX-1 and COX-2 may contribute to anti-platelet and anti-inflammatory effects of espresso and drip coffee extracts.


Assuntos
Coffea/química , Café/química , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Ácido Clorogênico/química , Ácido Clorogênico/farmacologia , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Agregação Plaquetária/efeitos dos fármacos
16.
Br J Haematol ; 191(4): 587-592, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33190267

RESUMO

Since the inception of the British Society for Haematology (BSH) 60 years ago, our increased scientific understanding of iron metabolism, together with clinical developments, have changed the way we diagnose and treat its disorders. In the UK, perhaps the most notable contributions relate to iron overload, some of which I will outline from personal experience. Diagnostically, this began with the identification of serum ferritin as a marker of iron overload and continued later with the application of MRI-based imaging techniques for iron and its distribution. Therapeutically, the first trials of both parenteral and oral chelation, which have radically changed the outcomes of transfusional iron-overloaded patients, took place in the UK and are now part of standard clinical practice. During this time, our scientific understanding of iron metabolism at a cellular and systemic level have advanced the diagnosis and treatment of inherited disorders of iron metabolism. There are potential novel applications related to our recent understanding of hepcidin metabolism and manipulation.


Assuntos
Doenças Hematológicas/complicações , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/metabolismo , Ferro/metabolismo , Biomarcadores , Gerenciamento Clínico , Suscetibilidade a Doenças , Doenças Hematológicas/etiologia , Doenças Hematológicas/terapia , Hemocromatose/diagnóstico , Hemocromatose/etiologia , Hemocromatose/metabolismo , Hemocromatose/terapia , Humanos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/terapia
18.
Biosci Rep ; 40(5)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32426811

RESUMO

Elevation of endothelial microparticles (EMPs) play an important role in the progression of inflammation-related vascular diseases such as cardiovascular diseases (CVDs). Thai perilla (Perilla frutescens) nutlets are rich in phenolic compounds and flavonoids that exert potent antioxidant and anti-inflammatory effects. We found that the ethyl acetate (EA) and ethanol (Eth) extracts of Thai perilla nutlets contain phenolic compounds such as luteolin, apigenin, chryseoriol and their glycosides, which exhibit antioxidant activity. The goal of the present study was to investigate the effects of the extracts on endothelial activation and EMPs generation in tumour necrosis factor-α (TNF-α)-induced EA.hy926 cells. We found that TNF-α (10 ng/ml) activated EA.hy926 cells and subsequently generated EMPs. Pre-treatment with the extracts significantly attenuated endothelial activation by decreasing the expression of the intracellular adhesion molecule-1 (ICAM-1) in a dose-dependent manner. Only the Eth extract showed protective effects against overproduction of interleukin-6 (IL-6) in the activated cells. Furthermore, the extracts significantly reduced TNF-α-enhanced EMPs generation in a dose-dependent manner. In conclusion, Thai perilla nutlet extracts, especially the Eth extract, may have potential to protect endothelium against vascular inflammation through the inhibition of endothelial activation and the generation of endothelial microparticles (EMPs).


Assuntos
Aterosclerose/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Perilla frutescens/química , Extratos Vegetais/farmacologia , Aterosclerose/imunologia , Aterosclerose/patologia , Linhagem Celular , Micropartículas Derivadas de Células/metabolismo , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/imunologia , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Nozes/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
19.
Molecules ; 25(11)2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32471050

RESUMO

Plant seeds have been found to contain bioactive compounds that have potential nutraceutical benefits. Guava seeds (Psidium guajava) are by-products in the beverage and juice industry; however, they can be utilized for a variety of commercial purposes. This study was designed to analyze the phytochemicals of the n-hexane extract of guava seed oil (GSO), to study its free-radical scavenging activity, and to monitor the changes in serum lipids and fatty acid profiles in rats that were fed GSO. The GSO was analyzed for phytochemicals using chromatographic methods. It was also tested for free-radical scavenging activity in hepatoma and neuroblastoma cells, and analyzed in terms of serum lipids and fatty acids. GSO was found to contain phenolic compounds (e.g., chlorogenic acid and its derivatives) and phytosterols (e.g., stimasterol, ß-sitosterol and campesterol), and exerted radical-scavenging activity in cell cultures in a concentration-dependent manner. Long-term consumption of GSO did not increase cholesterol and triglyceride levels in rat serum, but it tended to decrease serum fatty acid levels in a concentration-dependent manner. This is the first study to report on the lipid, phytosterol and phenolic compositions, antioxidant activity, and the hepato- and neuro-protection of hydrogen peroxide-induced oxidative stress levels in the GSO extract.


Assuntos
Fenóis/sangue , Fitosteróis/sangue , Óleos de Plantas/química , Psidium/química , Sementes/química , Animais , Antioxidantes/metabolismo , Carcinoma Hepatocelular/sangue , Colesterol/análogos & derivados , Colesterol/sangue , Feminino , Hexanos/química , Neoplasias Hepáticas/sangue , Masculino , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Sitosteroides/sangue , Triglicerídeos/sangue
20.
Int J Mol Sci ; 21(7)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235485

RESUMO

Aceruloplasminemia is a rare autosomal recessive genetic disease characterized by mild microcytic anemia, diabetes, retinopathy, liver disease, and progressive neurological symptoms due to iron accumulation in pancreas, retina, liver, and brain. The disease is caused by mutations in the Ceruloplasmin (CP) gene that produce a strong reduction or absence of ceruloplasmin ferroxidase activity, leading to an impairment of iron metabolism. Most patients described so far are from Japan. Prompt diagnosis and therapy are crucial to prevent neurological complications since, once established, they are usually irreversible. Here, we describe the largest series of non-Japanese patients with aceruloplasminemia published so far, including 13 individuals from 11 families carrying 13 mutations in the CP gene (7 missense, 3 frameshifts, and 3 splicing mutations), 10 of which are novel. All missense mutations were studied by computational modeling. Clinical manifestations were heterogeneous, but anemia, often but not necessarily microcytic, was frequently the earliest one. This study confirms the clinical and genetic heterogeneity of aceruloplasminemia, a disease expected to be increasingly diagnosed in the Next-Generation Sequencing (NGS) era. Unexplained anemia with low transferrin saturation and high ferritin levels without inflammation should prompt the suspicion of aceruloplasminemia, which can be easily confirmed by low serum ceruloplasmin levels. Collaborative joint efforts are needed to better understand the pathophysiology of this potentially disabling disease.


Assuntos
Ceruloplasmina/deficiência , Ceruloplasmina/genética , Distúrbios do Metabolismo do Ferro/genética , Doenças Neurodegenerativas/genética , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Distúrbios do Metabolismo do Ferro/diagnóstico , Distúrbios do Metabolismo do Ferro/patologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/patologia
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