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1.
Ann Hematol ; 103(6): 2173-2176, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38637332

RESUMO

A 58-year-old female was found to have hyperferritinemia (Serum ferritin:1683 ng/mL) during work-up for mild normocytic anemia. Transferrin saturation(TSAT) was low-normal. Magnetic resonance imaging (MRI) abdomen showed evidence of hepatic iron deposition. Liver biopsy showed 4 + hepatic iron deposition without any evidence of steatosis or fibrosis. Quantitative liver iron was elevated at 348.3 µmol/g dry liver weight [Reference range(RR): 3-33 µmol/g dry liver weight]. She was presumptively diagnosed with tissue iron overload, cause uncertain. A diagnosis of ferroportin disease (FD) was considered, but the pattern of iron distribution in the liver, mainly within the hepatic parenchyma (rather than in the hepatic Kupffer cells seen in FD), and the presence of anemia (uncommon in FD) made this less likely. She was treated with intermittent phlebotomy for over a decade with poor tolerance due to worsening normocytic to microcytic anemia. A trial of deferasirox was done but it was discontinued after a month due to significant side effects. During the course of treatment, her ferritin level decreased. Over the past 1.5 years, she developed progressively worsening neurocognitive decline. MRI brain showed areas of susceptibility involving basal ganglia, midbrain and cerebellum raising suspicion for metabolic deposition disease. Neuroimaging findings led to testing for serum copper and ceruloplasmin levels which were both found to be severely low. Low serum copper, ceruloplasmin levels and neuroimaging findings led us to consider Wilson disease however prior liver biopsy showing elevated hepatic iron rather than hepatic copper excluded the diagnosis of Wilson disease. After shared decision making, ceruloplasmin gene analysis was not pursued due to patient's preference and prohibitive cost of testing. The diagnosis of aceruloplasminemia was ultimately made. The biochemical triad of hyperferritinemia, low-normal TSAT and microcytic anemia should raise the possibility of aceruloplasminemia. Since neurological manifestations are rare in most inherited iron overload syndromes, neurological symptoms in a patient with tissue iron overload should prompt consideration of aceruloplasminemia as a differential diagnosis.


Assuntos
Ceruloplasmina , Distúrbios do Metabolismo do Ferro , Imageamento por Ressonância Magnética , Humanos , Feminino , Pessoa de Meia-Idade , Ceruloplasmina/deficiência , Ceruloplasmina/análise , Distúrbios do Metabolismo do Ferro/diagnóstico , Distúrbios do Metabolismo do Ferro/genética , Doenças Neurodegenerativas/diagnóstico , Fígado/patologia , Fígado/metabolismo , Fígado/diagnóstico por imagem , Ferritinas/sangue , Ferro/metabolismo , Ferro/sangue , Diagnóstico Diferencial , Sobrecarga de Ferro/diagnóstico , Deferasirox/uso terapêutico
2.
Neurochem Int ; 176: 105725, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38561151

RESUMO

Epilepsy constitutes a global health concern, affecting millions of individuals and approximately one-third of patients exhibit drug resistance. Recent investigations have revealed alterations in cerebral iron content in both epilepsy patients and animal models. However, the extant literature lacks a comprehensive exploration into the ramifications of modulating iron homeostasis as an intervention in epilepsy. This study investigated the impact of deferasirox, a iron ion chelator, on epilepsy. This study unequivocally substantiated the antiepileptic efficacy of deferasirox in a kainic acid-induced epilepsy model. Furthermore, deferasirox administration mitigated seizure susceptibility in a pentylenetetrazol-induced kindling model. Conversely, the augmentation of iron levels through supplementation has emerged as a potential exacerbating factor in the precipitating onset of epilepsy. Intriguingly, our investigation revealed a hitherto unreported discovery: ITPRIP was identified as a pivotal modulator of excitatory synaptic transmission, regulating seizures in response to deferasirox treatment. In summary, our findings indicate that deferasirox exerts its antiepileptic effects through the precise targeting of ITPRIP and amelioration of cerebral iron homeostasis, suggesting that deferasirox is a promising and novel therapeutic avenue for interventions in epilepsy.


Assuntos
Anticonvulsivantes , Encéfalo , Deferasirox , Epilepsia , Homeostase , Quelantes de Ferro , Ferro , Deferasirox/farmacologia , Ferro/metabolismo , Animais , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Masculino , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Camundongos , Excitação Neurológica/efeitos dos fármacos , Pentilenotetrazol/toxicidade , Ratos Sprague-Dawley
3.
Drug Dev Ind Pharm ; 50(3): 223-235, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38305197

RESUMO

BACKGROUND: Breast cancer (BC) stands as the second-leading cause of mortality among women worldwide. Many chemotherapeutic treatments for BC come with significant adverse effects. Additionally, BC is recognized as one of the most resistant forms of malignancy to treatment. Consequently, there exists a critical need for innovative therapeutic agents that are both highly effective and exhibit reduced toxicity and side effects for patients. Deferasirox (DFX), an iron-chelating drug approved by the FDA for oral use, emerges as a promising contender in the fight against BC proliferation. DFX, primarily administered orally, is utilized to address chronic iron excess resulting from blood transfusions, and it is the inaugural treatment for chronic iron overload syndrome. However, DFX encounters limitations due to its poor water solubility. AIM: This study aimed at incorporating DFX into lipid nanocapsules (DFX-LNCs) followed by investigating the anticancer effect of the DFX nanoform as compared to free DFX in-vitro and on an orthotopic BC mouse model in-vivo. METHODS: The DFX-LNCs was prepared and imaged using TEM and also characterized in terms of particle size (PS), zeta potential (ZP), and polydispersity index (PDI) using DLS. Moreover, drug release, cytotoxicity, and anticancer effect were assessed in-vitro, and in-vivo. RESULTS: The results revealed that DFX-LNCs are more cytotoxic than free DFX with IC50 of 4.417 µg/ml and 16.114 µg/ml, respectively, while the plain LNCs didn't show any cytotoxic effect on the 4T1 cell line (IC50 = 122.797 µg/ml). Besides, the apoptotic effect of DFX-LNCs was more pronounced than that of free DFX, as evidenced by Annexin V/PI staining, increased BAX expression, and decreased expression of BcL-2. Moreover, DFX-LNCs showed a superior antitumor effect in-vivo with potent antioxidant and anti-proliferative effects. CONCLUSION: The newly developed DFX nanoform demonstrated a high potential as a promising therapeutic agent for BC treatment.


Assuntos
Neoplasias da Mama , Sobrecarga de Ferro , Humanos , Feminino , Camundongos , Animais , Deferasirox/farmacologia , Deferasirox/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quelantes de Ferro/efeitos adversos , Ferro/uso terapêutico , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/tratamento farmacológico
4.
Hemoglobin ; 48(1): 47-55, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38369714

RESUMO

The study aimed to determine efficacy and safety of generic deferasirox monotherapy. Deferasirox was administered in transfusion-induced iron overloaded thalassemia. Efficacy was defined as responders and nonresponders by ≤ 15 reduced serum ferritin from baseline. Adverse events were also monitored. Fifty-two patients with mainly Hb E/ß-thalassemia at the mean (SD) age of 8.7 (4.1) years, were enrolled. The mean (SD) daily transfusion iron load was 0.47 (0.1) mg/kg and maximum daily deferasirox was 35.0 (6.2) mg/kg. Altogether, 52, 40 and 18 patients completed the first, second and third years of study, respectively. The median baseline serum ferritin 2,383 ng/mL decreased to 1,478, 1,038 and 1,268 ng/mL at the end of first, second and third years, respectively, with overall response rate at 73.1% (38/52). Patients with baseline serum ferritin >2,500 ng/mL showed a change in serum ferritin higher than those ≤2,500 ng/mL starting from the 9th month of chelation. Adverse events were found in 5 of 52 patients (9.6%) including transaminitis (n = 2), one each of proteinuria, rash and proximal tubular dysfunction which resolved after transient stopping or decreasing the chelation dose. Generic deferasirox was effective and safe among pediatric patients with transfusion-induced iron overloaded thalassemia.


Assuntos
Sobrecarga de Ferro , Talassemia , Humanos , Criança , Deferasirox/efeitos adversos , Quelantes de Ferro/efeitos adversos , Benzoatos/efeitos adversos , Triazóis/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Talassemia/tratamento farmacológico , Ferro , Ferritinas
5.
BMJ Open ; 14(2): e077342, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331857

RESUMO

INTRODUCTION: Despite the improvement in medical management, many patients with transfusion-dependent ß-thalassaemia die prematurely due to transfusion-related iron overload. As per the current guidelines, the optimal chelation of iron cannot be achieved in many patients, even with two iron chelators at their maximum therapeutic doses. Here, we evaluate the efficacy and safety of triple combination treatment with deferoxamine, deferasirox and deferiprone over dual combination of deferoxamine and deferasirox on iron chelation in patients with transfusion-dependent ß-thalassaemia with very high iron overload. METHODS AND ANALYSIS: This is a single-centre, open-label, randomised, controlled clinical trial conducted at the Adult and Adolescent Thalassaemia Centre of Colombo North Teaching Hospital, Ragama, Sri Lanka. Patients with haematologically and genetically confirmed transfusion-dependent ß-thalassaemia are enrolled and randomised into intervention or control groups. The intervention arm will receive a combination of oral deferasirox, oral deferiprone and subcutaneous deferoxamine for 6 months. The control arm will receive the combination of oral deferasirox and subcutaneous deferoxamine for 6 months. Reduction in iron overload, as measured by a reduction in the serum ferritin after completion of the treatment, will be the primary outcome measure. Reduction in liver and cardiac iron content as measured by T2* MRI and the side effect profile of trial medications are the secondary outcome measures. ETHICS AND DISSEMINATION: Ethical approval for the study has been obtained from the Ethics Committee of the Faculty of Medicine, University of Kelaniya (Ref. P/06/02/2023). The trial results will be disseminated in scientific publications in reputed journals. TRIAL REGISTRATION NUMBER: The trial is registered in the Sri Lanka Clinical Trials Registry (Ref: SLCTR/2023/010).


Assuntos
Sobrecarga de Ferro , Talassemia beta , Adulto , Adolescente , Humanos , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Benzoatos/uso terapêutico , Benzoatos/efeitos adversos , Triazóis/efeitos adversos , Piridonas , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Quelantes de Ferro/efeitos adversos , Ferro/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Br J Haematol ; 204(5): 2049-2056, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38343073

RESUMO

Iron overload from repeated transfusions has a negative impact on cardiac function, and iron chelation therapy may help prevent cardiac dysfunction in transfusion-dependent patients with myelodysplastic syndromes (MDS). TELESTO (NCT00940602) was a prospective, placebo-controlled, randomised study to evaluate the iron chelator deferasirox in patients with low- or intermediate-1-risk MDS and iron overload. Echocardiographic parameters were collected at screening and during treatment. Patients receiving deferasirox experienced a significant decrease in the composite risk of hospitalisation for congestive heart failure (CHF) or worsening of cardiac function (HR = 0.23; 95% CI: 0.05, 0.99; nominal p = 0.0322) versus placebo. No significant differences between the arms were found in left ventricular ejection fraction, ventricular diameter and mass or pulmonary artery pressure. The absolute number of events was low, but the enrolled patients were younger than average for patients with MDS, with no serious cardiac comorbidities and a modest cardiovascular risk profile. These results support the effectiveness of deferasirox in preventing cardiac damage caused by iron overload in this patient population. Identification of patients developing CHF is challenging due to the lack of distinctive echocardiographic features. The treatment of iron overload may be important to prevent cardiac dysfunction in these patients, even those with moderate CHF risk.


Assuntos
Deferasirox , Quelantes de Ferro , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Humanos , Deferasirox/uso terapêutico , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/complicações , Masculino , Feminino , Quelantes de Ferro/uso terapêutico , Pessoa de Meia-Idade , Idoso , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/tratamento farmacológico , Estudos Prospectivos , Benzoatos/uso terapêutico , Benzoatos/efeitos adversos , Insuficiência Cardíaca/etiologia , Reação Transfusional/etiologia , Ecocardiografia , Adulto , Idoso de 80 Anos ou mais , Triazóis/uso terapêutico , Triazóis/efeitos adversos , Transfusão de Sangue
7.
PLoS One ; 19(2): e0289248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38335199

RESUMO

BACKGROUND: Agomelatine (AGO) is an antidepressant with unique pharmacological effects; however, its underlying mechanisms remain unknown. In this study, we examined agomelatine's effects on catalase activity, oxidative stress, and inflammation. METHODS: Chronic restraint stress (CRS) model mice were established over 4 weeks, and AGO 50 mg/kg was administered to different groups alongside a deferasirox (DFX) 10 mg/kg gavage treatment. Behavioral tests were performed to assess the effect of AGO on the remission of depression-like behaviors. Meanwhile, the expression of CAT, the oxidative stress signaling pathway and inflammatory protein markers were assessed using ELISA, qRT-PCR, Western blot, and immunohistochemistry. RESULTS: Four weeks of AGO treatment significantly improved depression-like behavior in mice through the activation of catalase in the hippocampus and serum of the model mice, increased superoxide dismutase expression, reduced malondialdehyde expression, and reduced oxidative stress damage. Deferasirox was found to offset this therapeutic effect partially. In addition, the inflammatory pathway (including nuclear factor-κB and nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor, alpha) was not significantly altered. CONCLUSIONS: AGO can exert antidepressant effects by altering oxidative stress by modulating catalase activity.


Assuntos
Antioxidantes , Depressão , Camundongos , Animais , Depressão/tratamento farmacológico , Depressão/etiologia , Depressão/prevenção & controle , Catalase/metabolismo , Deferasirox/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico
8.
Blood Transfus ; 22(1): 75-85, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37146300

RESUMO

BACKGROUND: In transfusion-dependent thalassemia patients who started regular transfusions in early childhood, we prospectively and longitudinally evaluated the efficacy on pancreatic iron of a combined deferiprone (DFP) + desferrioxamine (DFO) regimen versus either oral iron chelator as monotherapy over a follow-up of 18 months. MATERIALS AND METHODS: We selected patients consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia network who received a combined regimen of DFO+DFP (No.=28) or DFP (No.=61) or deferasirox (DFX) (No.=159) monotherapy between the two magnetic resonance imaging scans. Pancreatic iron overload was quantified by the T2* technique. RESULTS: At baseline no patient in the combined treatment group had a normal global pancreas T2* (≥26 ms). At follow-up the percentage of patients who maintained a normal pancreas T2* was comparable between the DFP and DFX groups (57.1 vs 70%; p=0.517).Among the patients with pancreatic iron overload at baseline, global pancreatic T2* values were significantly lower in the combined DFO+DFP group than in the DFP or DFX groups. Since changes in global pancreas T2* values were negatively correlated with baseline pancreas T2* values, the percent changes in global pancreas T2* values, normalized for the baseline values, were considered. The percent changes in global pancreas T2* values were significantly higher in the combined DFO+DFP group than in either the DFP (p=0.036) or DFX (p=0.030) groups. DISCUSSION: In transfusion-dependent patients who started regular transfusions in early childhood, combined DFP+DFO was significantly more effective in reducing pancreatic iron than was either DFP or DFX.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Humanos , Pré-Escolar , Ferro/uso terapêutico , Deferasirox , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Piridonas/uso terapêutico , Talassemia beta/diagnóstico por imagem , Talassemia beta/tratamento farmacológico , Benzoatos/uso terapêutico , Triazóis/uso terapêutico , Quimioterapia Combinada , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Pâncreas/diagnóstico por imagem
10.
Auris Nasus Larynx ; 51(2): 271-275, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37903661

RESUMO

OBJECTIVE: The role of iron chelation in causing hearing loss (HL) is still unclear. The present study assessed the prevalence of HL among transfusion-dependent thalassemia (TDT) patients who underwent audiological follow-up over a 20-year period. METHODS: We retrospectively analyzed clinical records and audiological tests from January 1990 (T0) to December 2022 (T22) of a group of TDT patients who received iron chelation therapy with deferoxamine (DFO), deferiprone (DFP) or deferasirox (DFX), in monotherapy or as part of combination therapy. RESULTS: A total of 42 adult TDT patients (18 male, 24 female; age range: 41-55 years; mean age: 49.2 ± 3.7 years) were included in the study. At the T22 assessment, the overall prevalence of sensorineural HL was 23.8 % (10/42). When patients were stratified into two groups, with and without ototoxicity, no differences were observed for sex, age, BMI, creatinine level, pre-transfusional hemoglobin, start of transfusions, cardiac or hepatic T2 MRI; only ferritin serum values and duration of chelation were significantly higher (p = 0.02 and p = 0.01, respectively) in patients with hearing impairment in comparison to those with normal hearing. CONCLUSION: This study with long-term follow-up suggests that iron chelation therapy might induce ototoxicity; therefore, a long and accurate audiological follow-up should be performed in TDT patients.


Assuntos
Sobrecarga de Ferro , Ototoxicidade , Talassemia beta , Adulto , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Talassemia beta/epidemiologia , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/etiologia , Seguimentos , Estudos Retrospectivos , Ototoxicidade/complicações , Ototoxicidade/tratamento farmacológico , Benzoatos/uso terapêutico , Triazóis/uso terapêutico , Piridonas/uso terapêutico , Quelantes de Ferro/uso terapêutico , Ferro/uso terapêutico , Audição
11.
Complement Ther Clin Pract ; 53: 101804, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832335

RESUMO

BACKGROUND AND PURPOSE: Iron overload in the body is associated with serious and irreversible tissue damage. This study aimed to investigate the iron-chelating, antioxidant, anti-inflammatory, and hepatoprotective activities of grape seed extract (GSE) supplement as well as its safety in ß-thalassemia major (ß-TM) pediatric patients receiving deferasirox as a standard iron-chelation therapy. MATERIALS AND METHODS: The children were randomly allocated to either GSE group (n = 30) or control group (n = 30) to receive GSE (100 mg/day) or placebo capsules, respectively, for 4 weeks. The serum levels of iron, ferritin, total iron-binding capacity (TIBC), alanine transaminase (ALT), aspartate aminotransferase (AST), tumor necrosis factor alpha (TNF-α), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), and glutathione (GSH) as well as superoxide dismutase (SOD) activity and hemoglobin (Hb) concentration were measured pre-and post-intervention. RESULTS: GSE supplement significantly attenuated the serum levels of iron (p = 0.030), ferritin (p = 0.017), ALT (p = 0.000), AST (p = 0.000), TNF-α (p = 0.000), and hs-CRP (p = 0.001). The TIBC level (p = 0.020) significantly enhanced in the GSE group compared with the placebo group. Moreover, GSE supplement remarkably improved the oxidative stress markers, MDA (p = 0.000) and GSH (p = 0.001). The changes in the SOD activity (p = 0.590) and Hb concentration (p = 0.670) were not statistically different between the groups. CONCLUSION: GSE supplement possesses several health beneficial influences on children with ß-TM by alleviating iron burden, oxidative stress, inflammation, and liver dysfunction.


Assuntos
Extrato de Sementes de Uva , Sobrecarga de Ferro , Hepatopatias , Talassemia beta , Criança , Humanos , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Proteína C-Reativa , Deferasirox/uso terapêutico , Ferritinas/metabolismo , Extrato de Sementes de Uva/farmacologia , Extrato de Sementes de Uva/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/complicações , Ferro/metabolismo , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Hepatopatias/complicações , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa
12.
Hum Exp Toxicol ; 42: 9603271231192361, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37526177

RESUMO

Iron is a necessary biological element and one of the richest in the human body, but it can cause changes in cell function and activity control. Iron is involved in a wide range of oxidation - reduction activities. Whenever iron exceeds the cellular metabolic needs, its excess causes changes in the products of cellular respiration, such as superoxide, hydrogen peroxide and hydroxyl. The formation of these compounds causes cellular toxicity. Lack of control over reactive oxygen species causes damages to DNA, proteins, and lipids. Conversely, superoxide, hydrogen peroxide and hydroxyl are reactive oxygen species, using antioxidants, restoring DNA function, and controlling iron stores lead to natural conditions. Iron poisoning causes clinical manifestations in the gastrointestinal tract, liver, heart, kidneys, and hematopoietic system. When serum iron is elevated, serum iron concentrations, total iron-binding capacity (TIBC) and ferritin will also increase. Supportive care is provided by whole bowel irrigation (WBI), esophagogastroduodenoscopy is required to evaluate mucosal injury and remove undissolved iron tablets. The use of chelator agents such as deferoxamine mesylate, deferasirox, deferiprone, deferitrin are very effective in removing excess iron. Of course, the combined treatment of these chelators plays an important role in increasing iron excretion, and reducing side effects.


Assuntos
Quelantes de Ferro , Ferro , Humanos , Ferro/metabolismo , Deferasirox , Deferiprona , Desferroxamina , Espécies Reativas de Oxigênio , Superóxidos , Peróxido de Hidrogênio , Piridonas , Benzoatos/uso terapêutico , Triazóis , DNA
13.
Korean J Intern Med ; 38(6): 893-902, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37599392

RESUMO

BACKGROUND/AIMS: Although rituximab, an antiCD20 monoclonal antibody, has dramatically improved the clinical outcomes of diffuse large B-cell lymphoma, rituximab resistance remains a challenge. METHODS: We developed a rituximab-resistant cell line (RRCL) by sequential exposure to gradually increasing concentrations of rituximab in a rituximab-sensitive cell line (RSCL). When the same dose of rituximab was administered, RRCL showed a smaller decrease in cell viability and apoptosis than RSCL. To determine the differences in gene expression between RSCL and RRCL, we performed next-generation sequencing. RESULTS: In total, 1,879 differentially expressed genes were identified, and in the over-representation analysis of Consensus-PathDB, mitogen-activated protein kinase (MAPK) signaling pathway showed statistical significance. MAPK13, which encodes the p38δ protein, was expressed more than four-fold in RRCL. Western blot analysis revealed that phosphop38 expression mainwas increased in RRCL, and when p38 inhibitor was administered, phosphop38 expression was significantly decreased. Therefore, we hypothesized that p38 MAPK activation was associated with rituximab resistance. Previous studies have suggested that p38 is associated with NF-κB activation. Deferasirox has been reported to inhibit NF-κB activity and suppress phosphorylation of the MAPK pathway. Furthermore, it also has cytotoxic effects on various cancers and synergistic effects in overcoming drug resistance. In this study, we confirmed that deferasirox induced dose-dependent cytotoxicity in both RSCL and RRCL, and the combination of deferasirox and rituximab showed a synergistic effect in RRCL at all combination concentrations. CONCLUSION: We suggest that p38 MAPK, especially p38δ, activation is associated with rituximab resistance, and deferasirox may be a candidate to overcome rituximab resistance.


Assuntos
Linfoma Difuso de Grandes Células B , Proteína Quinase 13 Ativada por Mitógeno , Humanos , Rituximab/farmacologia , Rituximab/uso terapêutico , Deferasirox/farmacologia , Proteína Quinase 13 Ativada por Mitógeno/genética , NF-kappa B , Anticorpos Monoclonais Murinos/genética , Anticorpos Monoclonais Murinos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Apoptose , Sequenciamento de Nucleotídeos em Larga Escala , Linhagem Celular Tumoral , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologia
14.
Chem Res Toxicol ; 36(8): 1255-1266, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37435843

RESUMO

Deferasirox (DFS) is used for the treatment of iron accumulation caused by the need for long-term blood transfusions, such as thalassemia or other rare anemia. Liver injury due to exposure to DFS has been documented, and the toxic mechanisms of DFS are unknown. The present study aimed to investigate the reactive metabolites of DFS in vitro and in vivo to help us understand the mechanisms of DFS hepatotoxicity. Two hydroxylated metabolites (5-OH and 5'-OH) were identified during incubation of DFS-supplemented rat liver microsomes. Such microsomal incubations fortified with glutathione (GSH) or N-acetylcysteine (NAC) as capture agents offered two GSH conjugates and two NAC conjugates. These GSH conjugates and NAC conjugates were also detected in bile and urine of rats given DFS. CYP1A2 and CYP3A4 were found to dominate the metabolic activation of DFS. Administration of DFS induced decreased cell survival in cultured primary hepatocytes. Pretreatment with ketoconazole and 1-aminobenzotrizole made hepatocytes less susceptible to the cytotoxicity of DFS.


Assuntos
Hepatócitos , Fígado , Ratos , Animais , Ativação Metabólica , Deferasirox/farmacologia , Deferasirox/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Microssomos Hepáticos/metabolismo , Acetilcisteína/metabolismo , Glutationa/metabolismo
15.
Transplant Cell Ther ; 29(8): 507.e1-507.e8, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37116582

RESUMO

Patients suffering from severe aplastic anemia (SAA) need frequent blood transfusions during allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, these transfusions can result in an excess of iron in the body tissues, which can negatively impact the success of transplantation. This study aimed to examine the impact of pretransplantation iron overload (IO) on the outcomes of allo-HSCT in patients with SAA. It also investigated whether iron chelation (IC) therapy is necessary to enhance transplantation outcomes in SAA patients by providing guidelines for determining when excess iron should be chelated. The study consisted of 2 parts. In cohort 1, which was retrospective and conducted from April 2012 to December 2018, SAA patients receiving their first allo-HSCT were divided into 2 groups based on their pretransplantation serum ferritin (SF) level: the IO group (SF >1000 ng/mL; n = 17) and the non-IO group (SF ≤1000 ng/mL; n = 48). Cohort 2, a prospective clinical trial conducted from January 2019 to July 2020, included SAA patients diagnosed with IO who were treated with IC therapy using deferasirox at a dose of 10 to 30 mg/kg. Patients were separated into 2 groups based on their pretransplantation SF level: the IC success (ICsuccess) group (SF ≤1000 ng/mL; n = 18) and the IC failure (ICfailure) group (SF >1000 ng/mL; n = 28). All participants were evaluated for the correlation between pretransplantation SF level and transplantation outcomes. A P value <.05 was considered statistically significant. There was no significant difference in the speed of engraftment among the 3 cell lineages or in the incidence of 100-day grade II-IV acute graft-versus-host disease (aGVHD), grade III-IV aGVHD, or 3-year chronic GVHD between the 2 groups in both cohorts. Of note, however, in cohort 1, both 1-year overall survival (OS) (41.2% versus 83.3%; P < .001) and 3-year OS (35.3% versus 83.3%; P < .001) were significantly worse in the IO group. Furthermore, 180-day transplantation related mortality (TRM) (47.1% versus 14.6%; P = .005) and 1-year TRM (52.9% versus 16.7%; P = .002) were significantly higher in the IO group. The IO group was significantly associated with inferior 3-year OS in both univariate and multivariate analyses. In cohort 2, 1-year OS (88.9% versus 42.9%; P = .003) and 3-year OS (83.3% versus 42.9%; P = .007) were significantly better in the ICsuccess group, whereas 180-day TRM (11.1% versus 39.3%; P = .040) and 1-year TRM (11.1% versus 57.1%; P = .003) were significantly lower in the ICsuccess group. These differences were confirmed in both univariate and multivariate analyses. This study involving 2 cohorts shows that pre-HSCT IO has a negative impact on transplantation outcomes in SAA patients. Chelating excess iron with an SF level <1000 ng/mL was found to be necessary and could potentially improve the outcomes.


Assuntos
Anemia Aplástica , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Sobrecarga de Ferro , Humanos , Anemia Aplástica/terapia , Deferasirox , Estudos Retrospectivos , Estudos Prospectivos , Resultado do Tratamento , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Ferro , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Quelantes de Ferro/uso terapêutico
16.
Transfus Apher Sci ; 62(3): 103702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37055329

RESUMO

Drug-induced nephrolithiasis can arise from insoluble components within medications or crystallization of metabolites due to changes in metabolism and urinary pH. The connection between drugs utilized for iron chelation therapy (ICT) and nephrolithiasis is not well understood. In this report, we describe two pediatric patients diagnosed with nephrolithiasis while undergoing treatment with the chelating agents deferasirox, deferiprone, and deferoxamine for iron overload secondary to repeat blood transfusion.


Assuntos
Sobrecarga de Ferro , Nefrolitíase , Talassemia beta , Humanos , Criança , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Deferasirox/efeitos adversos , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Benzoatos/efeitos adversos , Triazóis , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Nefrolitíase/induzido quimicamente , Nefrolitíase/complicações , Nefrolitíase/tratamento farmacológico , Ferro/uso terapêutico , Talassemia beta/terapia
17.
Int J Biol Macromol ; 238: 124126, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36944379

RESUMO

Deferasirox (DFX) is an iron-chelating agent effective in treating various kinds of cancers, which inhibits iron metabolism in cancer cells. The recent study aimed to prepare an injectable thermosensitive hydrogel based on lignocellulose and agarose containing deferasirox-loaded polypyrrole nanoparticles for local drug delivery in a combined chemo-photothermal therapy by laser light irradiation. Polypyrrole nanoparticles containing DFX were made by the emulsification method and optimized. Thermosensitive hydrogels were prepared by quaternary ammonium substituted agarose and TMPO-oxidized lignocellulose at different ratios, and the optimal hydrogel was selected based on gelation time, gelation temperature, and injectability. DFX- loaded polypyrrole nanoparticles were then added to the hydrogel, and the drug release, rheology test, injectability, degradation, and swelling percent, as well as cytotoxicity, and photothermal properties, were studied on B16F10, human melanoma cells. The hydrogel with 2 % anionic lignocellulose and 0.5 % cationic agarose showed the shortest gelation time and the highest mechanical strength. It transferred from a liquid state at 4 °C into a semisolid form at 37 °C with a gelation time of 10.3 min. The nanoparticles loaded in hydrogel showed dose-dependent cytotoxicity. The cytotoxic dose of the drug was reduced by laser light irradiation.


Assuntos
Melanoma , Nanopartículas , Timopoietinas , Humanos , Hidrogéis , Deferasirox/farmacologia , Polímeros , Sefarose , Terapia Fototérmica , Pirróis , Ferro , Proteínas Nucleares
18.
Expert Rev Hematol ; 16(2): 81-94, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36755516

RESUMO

INTRODUCTION: Regular blood transfusions in patients with thalassemia syndromes can cause iron overload resulting in complications including cirrhosis, heart problems, or endocrine abnormalities. To prevent iron overload toxicity in these patients, three iron chelators are currently FDA-approved for use: deferoxamine, deferasirox, and deferiprone. In the United States, deferiprone has been approved for three times daily dosing since 2011 and has recently gained approval for twice-daily administration. AREAS COVERED: A PubMed literature search was performed with the keywords 'deferiprone' and 'thalassemia.' Relevant original research studying deferiprone's effects on transfusional iron overload in patients with thalassemia syndromes was included. Exclusion criteria included case reports and review papers. Deferiprone is effective at reducing serum ferritin levels in patients with iron overload. Twice-daily administration provides a similar level of iron chelation as three times daily dosing with a comparable side effect profile and increased patient acceptability. EXPERT OPINION: New studies are highlighting deferiprone's potential for combination therapy with either deferoxamine or deferasirox to improve iron chelation. Deferiprone's ability to significantly decrease cardiac and liver iron content can be utilized in other transfusion-dependent hematologic conditions, as evidenced by its recent approval for use in the United States for sickle cell disease or other anemias.


Assuntos
Sobrecarga de Ferro , Talassemia , Humanos , Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Síndrome , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Quelantes de Ferro/uso terapêutico , Talassemia/complicações , Talassemia/terapia , Transfusão de Sangue , Piridonas/efeitos adversos , Benzoatos
19.
Eur J Haematol ; 110(5): 490-497, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36708354

RESUMO

Iron overload is a pathological condition resulting from a congenital impairment of its regulation, increased intestinal iron absorption secondary to bone marrow erythroid hyperplasia, or a chronic transfusional regimen. In normal conditions, intracellular and systemic mechanisms contribute to maintaining iron balance. When this complex homeostatic mechanism fails, an iron overload could be present. Detecting an iron overload is not easy. The gold standard remains the liver biopsy, even if it is invasive and dangerous. Identifying iron using noninvasive techniques allowed a better understanding of the rate of iron overload in different organs, with a low risk for the patient. Estimating serum ferritin (mg/L) is the easiest and, consequently, the most employed diagnostic tool for assessing body iron stores, even if it could be a not specific method. The most common hematological causes of iron overload are myelodysplastic syndromes, sickle cell disease, and thalassemia. In all of these conditions, three drugs have been approved for the treatment of iron overload: deferiprone, deferoxamine, and deferasirox. These chelators have been demonstrated to help lower tissue iron levels and prevent iron overload complications, improving event-free survival (EFS). Nowadays, the decision to start chelation and which chelator to choose remains the joint decision of the clinician and patient.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Humanos , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/uso terapêutico , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/uso terapêutico , Benzoatos/uso terapêutico , Triazóis , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Ferro
20.
J Inorg Biochem ; 241: 112131, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36706491

RESUMO

Capillary electrophoresis was used to estimate the solvolytic dissociation rate (kd) of metal complexes of deferasirox (DFX, H3L), a drug used to treat iron overload. Inert CoIIIL23- did not dissociate. The estimated kd value for FeIIIL23- was (2.7 ± 0.3) × 10-4 s-1 (298 K, pH 7.4). The kd values of other complexes (AlIIIL23-, NiIIL24-, and MnIIL-) were in the range 10-3-10-4 s-1. In contrast, ZnIIL- and CuIIL- were too labile to allow kd estimation. The fact that the half-life of FeIIIL23- (43.3 min) is shorter than the blood half-life of DFX (8-16 h) implies that the blood concentration of DFX should be high enough to prevent dissociation of FeIIIL23-. The possibility of a safer iron-chelation therapy that avoids excretion of other essential metal ions such as ZnII is discussed, highlighting the importance of selectivity in terms of kinetic stability.


Assuntos
Sobrecarga de Ferro , Ferro , Humanos , Deferasirox/uso terapêutico , Terapia por Quelação , Quelantes de Ferro , Eletroforese Capilar , Benzoatos
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