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1.
Neurochem Int ; 176: 105725, 2024 Mar 30.
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.

2.
Eur J Ophthalmol ; : 11206721241245740, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38562036

RESUMO

INTRODUCTION: Deferasirox is the only iron chelator available in oral formulation and a rare cause of pigmentary retinopathy. We report the first case of multimodal imaging in an adult with deferasirox retinopathy. METHODS: Case report and literature review, with search terms including deferasirox retinopathy and deferasirox toxicity. RESULTS: A 63-year-old man with end stage renal disease and transfusion-dependent anemia on deferasirox for one year presented with asymptomatic pigment epitheliopathy. Optical coherence tomography featured outer retinal and retinal pigment epithelial discontinuity corresponding to hypoautofluorescence on fundus autofluorescence and blocking on fluorescein angiography. Multifocal electroretinography revealed subtle reduction in all amplitudes. CONCLUSIONS: Retinal examinations should be considered for patients requiring chronic administration of deferasirox.

3.
BMC Pediatr ; 24(1): 244, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580952

RESUMO

BACKGROUND: ß-Thalassemia major (BTM) is one of the most common hereditary anemias worldwide. Patients suffer from iron overload that results from repeated blood transfusion This in turn leads to multiple organ damage and endocrinopathies. This study aims to assess the prevalence of growth retardation, hypothyroidism, and diabetes mellitus in children and adolescents with BTM treated at Dubai Thalassemia Centre. METHODS: A total of 105 children and adolescents were included in this retrospective observational study. RESULTS: 39 children and 66 adolescents' data were analyzed. Females composed 51.3% (n = 20) of children and 53.0% (n = 35) of adolescents. Pretransfusion hemoglobin below 9 gm/dl was observed in 10.8% (n = 4) and 10.6% (n = 7) in children and adolescents, respectively. The mean age of menarche was 13.5 years. Among all study participants, 22.6% (n = 14) had normal height velocity whereas 37.1% (n = 23) had reduced height velocity in one year and 40.3% (n = 25) had reduced height velocity in two consecutive years. The proportion of children and adolescents showing reduced height velocity was significantly higher in females compared to the males (90.6% versus 63.3%, respectively, Chi-square = 6.597, p-value = 0.010). Although none of the study participants had diabetes mellitus, 26.1% (n = 12/46) had pre-diabetes. Elevated TSH was observed in 14.7% (n = 5) children and 8.1% (n = 5) adolescents while low FT4 was reported in one child and one adolescent. CONCLUSION: Of all endocrinopathies seen among children and adolescents with BTM, growth delay remains the main concern for this group of patients. Effective treatment is key to further reducing endocrinopathies. Although the sample size is limited, we postulate that the low percentage of endocrinopathies among children with BTM treated at Dubai thalassemia center and the low level of pretransfusion anemia reflect the effective transfusion and chelation at the center.


Assuntos
Diabetes Mellitus , Hipotireoidismo , Sobrecarga de Ferro , Talassemia beta , Masculino , Criança , Feminino , Adolescente , Humanos , Talassemia beta/complicações , Talassemia beta/epidemiologia , Talassemia beta/terapia , Quelantes de Ferro/efeitos adversos , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia
4.
Cureus ; 16(2): e53644, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38455804

RESUMO

This network meta-analysis was conducted with the aim of comparing the efficacy and safety of deferiprone (DFP), deferasirox (DFX), and deferoxamine (DFO) in individuals with sickle cell disease (SCD) or transfusion-dependent anemia. This systematic review and meta-analysis adhered to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" guidelines. The search was conducted on electronic databases, including PubMed, CINAHIL, and EMBASE, from the inception of databases to January 10, 2024. Outcomes assessed in this study included a change in liver iron concentration (LIC) and a change in ferritin from baseline. For safety analysis, adverse events were compared among three treatment groups. A total of five studies were included in this meta-analysis. The pooled analysis showed that the change in LIC and serum ferritin from baseline was not significantly different in patients with SCD or other anemias. In terms of adverse events, deferiprone was the safest among all. In conclusion, deferiprone demonstrated noninferiority to deferoxamine and deferasirox in measures of iron load, presenting a viable treatment option. Safety outcomes revealed deferasirox carried a higher risk of adverse events compared to deferiprone, supporting its favorable safety profile.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38423705

RESUMO

Deferasirox is an iron-chelating drug developed by Novartis company for treatment of diseases accompanied by chronic iron overload; such as ß-thalassemia or sickle cell diseases. Owing to its advantages such as high affinity, specificity and wide therapeutic window, it is considered as first line treatment. The current chapter describes the physicochemical characteristics, mode of action, pharmacokinetics, therapeutic applications and synthetic methods for deferasirox. Moreover, it includes Fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance spectroscopy (NMR) analysis for its functional groups. In addition, the selected analytical methods are summarized to aid the analysts in their routine analysis of deferasirox.


Assuntos
Benzoatos , Sobrecarga de Ferro , Humanos , Deferasirox/farmacologia , Deferasirox/uso terapêutico , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Benzoatos/metabolismo , Triazóis/uso terapêutico , Triazóis/farmacocinética , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/metabolismo , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Ferro/uso terapêutico
6.
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
7.
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
8.
Br J Haematol ; 2024 Feb 11.
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.

9.
Int J Pediatr Otorhinolaryngol ; 177: 111868, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38252990

RESUMO

BACKGROUND: Hearing impairment has frequently been described in ß-thalassemia patients with a significant impact on the patients' quality of life. Most studies provided evidence of deferoxamine (DFO) dose-related ototoxicity, however, the data is scarce regarding deferasirox (DFX) as a sole iron chelator. AIM: We aimed to assess the prevalence and risk factors of sensorineural hearing loss (SNHL) and vestibular dysfunction in regularly transfused ß-thalassemia patients who had been treated with DFX film coated tablets. METHODS: We conducted a case control study on 57 transfusion dependent ß-thalassemia patients with a mean age of 15.3 years who received DFX FCT as monotherapy for at least one consecutive year, and 57 healthy age and sex-matching controls. Comprehensive audiological evaluations using pure tone audiometry (PTA) and transient evoked otoacoustic emission (TEOAE) as well as vestibular evaluation using Video-nystagmography (VNG) were done. RESULTS: SNHL was identified in 12 patients (21.1 %) using PTA and a statistically significant difference was detected between controls and patients at 6 KHz and 12 KHz frequencies. A higher incidence of SNHL was detected using TEOAE, 22 patients (43.1 %) failed to pass TEOAE, with a statistically significant decrease in the signal at frequencies 1, 4 KHz bilaterally and at frequencies 1.5, 2 KHz in the right ear compared to controls. Canal paresis was detected in 21 (36.8 %) of thalassemic children using bithermal caloric test with significantly more unilateral weakness than control children (P = 0.008). We found no significant correlation between audio-vestibular dysfunction and age, sex, serum ferritin, frequency of blood transfusion and dose of DFX FCT in thalassemic children. CONCLUSION: We conclude that the incidence of SNHL and vestibular dysfunction was high among transfusion dependent ß-thalassemia patients. Therefore, we recommend performing pre-treatment baseline audio-vestibular assessment and yearly audio-vestibular monitoring to early detect high risk patients and initiate timely management to prevent permanent damage.


Assuntos
Perda Auditiva Neurossensorial , Talassemia beta , Criança , Humanos , Adolescente , Talassemia beta/complicações , Talassemia beta/terapia , Deferasirox/efeitos adversos , Desferroxamina/efeitos adversos , Estudos de Casos e Controles , Qualidade de Vida , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/epidemiologia
10.
Eur J Med Chem ; 264: 116026, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38070429

RESUMO

Here we designed and synthesized 58 deferasirox derivatives with the aim of discovering novel antifungal agents. Most compounds exhibited moderate to excellent in vitro antifungal activities against Cryptococcus neoformans H99 with MIC values ranging from 0.25 µg/mL to 16 µg/mL, including ten compounds with MIC values less than 1 µg/mL that were further screened against an additional six pathogenic fungi. This class of compounds showed high potency against Candida glabrata with MIC values ranging from <0.125 µg/mL to 1 µg/mL. We identified that compound 54 has high potency against 14 strains of Candida glabrata spp. and Cryptococcus spp. with MIC values ranging from <0.125 µg/mL to 1 µg/mL. In addition, compound 54 significantly reduced the CFU in a mouse model of disseminated infection with Cryptococcus neoformans H99 at a dose of 10 mg/kg, which is comparable to FLC. Further investigations on compound 54 are currently in progress.


Assuntos
Criptococose , Cryptococcus neoformans , Camundongos , Animais , Antifúngicos/farmacologia , Deferasirox/farmacologia , Testes de Sensibilidade Microbiana , Criptococose/tratamento farmacológico
11.
J Am Heart Assoc ; 13(1): e031219, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38158218

RESUMO

BACKGROUND: Ferroptosis, an iron-dependent form of regulated cell death, is a major cell death mode in myocardial ischemia reperfusion (I/R) injury, along with mitochondrial permeability transition-driven necrosis, which is inhibited by cyclosporine A (CsA). However, therapeutics targeting ferroptosis during myocardial I/R injury have not yet been developed. Hence, we aimed to investigate the therapeutic efficacy of deferasirox, an iron chelator, against hypoxia/reoxygenation-induced ferroptosis in cultured cardiomyocytes and myocardial I/R injury. METHODS AND RESULTS: The effects of deferasirox on hypoxia/reoxygenation-induced iron overload in the endoplasmic reticulum, lipid peroxidation, and ferroptosis were examined in cultured cardiomyocytes. In a mouse model of I/R injury, the infarct size and adverse cardiac remodeling were examined after treatment with deferasirox, CsA, or both in combination. Deferasirox suppressed hypoxia- or hypoxia/reoxygenation-induced iron overload in the endoplasmic reticulum, lipid peroxidation, and ferroptosis in cultured cardiomyocytes. Deferasirox treatment reduced iron levels in the endoplasmic reticulum and prevented increases in lipid peroxidation and ferroptosis in the I/R-injured myocardium 24 hours after I/R. Deferasirox and CsA independently reduced the infarct size after I/R injury to a similar degree, and combination therapy with deferasirox and CsA synergistically reduced the infarct size (infarct area/area at risk; control treatment: 64±2%; deferasirox treatment: 48±3%; CsA treatment: 48±4%; deferasirox+CsA treatment: 37±3%), thereby ameliorating adverse cardiac remodeling on day 14 after I/R. CONCLUSIONS: Combination therapy with deferasirox and CsA may be a clinically feasible and effective therapeutic approach for limiting I/R injury and ameliorating adverse cardiac remodeling after myocardial infarction.


Assuntos
Ferroptose , Sobrecarga de Ferro , Infarto do Miocárdio , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Camundongos , Animais , Ciclosporina/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Deferasirox/farmacologia , Deferasirox/metabolismo , Deferasirox/uso terapêutico , Remodelação Ventricular , Miócitos Cardíacos/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão/metabolismo , Ferro/metabolismo , Hipóxia/metabolismo , Sobrecarga de Ferro/metabolismo , Isquemia Miocárdica/metabolismo
12.
Cureus ; 15(11): e48276, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38058350

RESUMO

Despite the established efficacy of iron chelation therapy in transfusion-induced iron-overloaded patients, there is no universal agreement regarding the choice of an optimal chelating regimen. Deferasirox (DFX) and deferiprone (DFP) are two oral iron chelators, and combination usage demonstrated effectiveness as an alternative to monotherapies in patients with a limited response to monotherapy. The present systematic review aimed to assess the evidence regarding the outcomes of combined DFP and DFX in iron-overloaded patients. An online search was conducted in PubMed, Scopus, Web of Science, and CENTRAL databases. Interventional and observational studies that assessed the outcomes of combined DFP and DFX in iron-overloaded patients were included. Eleven studies (12 reports) were considered in this meta-analysis. The studies included dual iron chelation strategies for a number of diagnoses. Single-arm studies (n =7) showed a reduction of serum ferritin, which reached the level of statistical significance in three studies. Likewise, most studies reported a numerical reduction in liver iron concentration (LIC) and increased cardiac MRI-T2* values after chelating therapy. Alternatively, comparative studies showed no significant difference in post-treatment serum ferritin between DFX plus DFP and DFX/DFP plus deferoxamine (DFO). The adherence to combination therapy was good to average in nearly 66.7-100% of the patients across four studies. One study reported a poor adherence rate. The combined regimen was generally tolerable, with no reported incidence of serious adverse events among the included studies. In conclusion, the DFP and DFX combination is a safe and feasible option for iron overload patients with a limited response to monotherapy.

13.
J Blood Med ; 14: 589-594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047247

RESUMO

Chronic kidney disease (CKD) is a major global health concern, affecting millions of people worldwide. The progressive decline in kidney function often necessitates renal replacement therapy, such as hemodialysis (HD) or peritoneal dialysis (PD), to maintain a patient's health. Iron overload, which is common in CKD patients on dialysis, can lead to severe complications, including cardiovascular disease and infections where most of the existing iron chelators are deemed unsuitable due to their suboptimal clearance in patients with compromised renal function, it becomes a significant challenge to effectively manage iron overload. Deferasirox (DFX), an oral iron chelator, has emerged as a promising treatment option for managing iron overload in these patients. However, the use of DFX comes with its unique set of challenges, such as its cost, potential side effects, and the need for close monitoring of patients, as well as the noticeable scarcity of comprehensive and rigorous clinical studies confirming its efficacy and safety of DFX. In this review, we delve into both the promising prospects and the emerging challenges associated with DFX use in managing CKD patients on HD or PD, striving for a comprehensive understanding that informs better clinical practice and patient care.

14.
Rev Alerg Mex ; 70(4): 159-162, 2023 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-37933925

RESUMO

Background: Deferasirox is an active iron chelator, used in the treatment of iron overload such as hemochromatosis. Up to 28% may present adverse reactions to said drug. A desensitization protocol for this drug may be useful when there are no other therapeutic options. Case report: A 52-year-old female with a diagnosis of hemochromatosis who began treatment with phlebotomy, poor response and tolerance, so it was decided to treat with deferasirox 500 mg daily, presenting symptoms of urticaria and angioedema on the third dose. Hospitalization was decided for a desensitization protocol with an initial dose of 0.6mg with a gradual increase in the dose, reaching a maintenance dose of 500 mg per day on the third day. Conclusions: The rapid desensitization protocol for Deferasirox is useful when there is no response or therapeutic alternative.


Antecedentes: Deferasirox es un quelante de hierro activo, indicado en el tratamiento de pacientes con hemocromatosis; sin embargo, se ha informado que el 28% de los casos puede tener reacciones adversas al fármaco. El protocolo de desensibilización para deferasirox puede ser útil cuando no se dispone de opciones terapéuticas adicionales. Reporte de caso: Paciente femenina de 52 años, con diagnóstico de hemocromatosis, quien luego de practicarle una flebotomía se observó poca respuesta y tolerancia al tratamiento, por lo que se decidió indicar deferasirox (500 mg/día), manifestando un cuadro de urticaria y angioedema en la tercera toma. Se decidió hospitalizarla para implementar el protocolo de desensibilización con una dosis inicial de 0.6 mg, con incremento gradual hasta llegar, al tercer día, a una dosis de mantenimiento de 500 mg/día. Conclusiones: El protocolo de desensibilización rápida con deferasirox es útil cuando no se obtiene respuesta satisfactoria con la flebotomía o no se dispone opciones de tratamiento alternativas.


Assuntos
Deferasirox , Hemocromatose , Quelantes de Ferro , Feminino , Humanos , Pessoa de Meia-Idade , Deferasirox/uso terapêutico , Hemocromatose/tratamento farmacológico , Quelantes de Ferro/uso terapêutico
15.
Indian J Pharmacol ; 55(5): 335-337, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929413

RESUMO

Iron chelators have significantly reduced the morbidity associated with iron overload and improved the quality of life in children with beta-thalassemia major. A 5-year-old female child with beta-thalassemia major on recurrent transfusions and oral chelation with deferasirox was brought with repeated episodes of frank hematemesis and progressive lethargy. Her evaluation revealed anemia, leukocytosis, and deranged liver function with coagulopathy. She was given red blood cell and plasma transfusions with liver supportive medication and proton-pump inhibitor (PPI) infusion. Her upper gastrointestinal endoscopy revealed multiple ulcers in all three parts of the duodenum, which in the absence of any other likely etiology were attributed to prolonged use of oral deferasirox. The child improved with the above-mentioned measures. Chelation therapy was withheld for 2 weeks and restarted at a lower dose using enteric-coated preparation while PPIs were given for 8 weeks. She showed sustained improvement and remained well on follow-up.


Assuntos
Úlcera Duodenal , Choque Hemorrágico , Talassemia beta , Pré-Escolar , Feminino , Humanos , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Deferasirox/efeitos adversos , Úlcera Duodenal/induzido quimicamente , Úlcera Duodenal/tratamento farmacológico , Quelantes de Ferro/efeitos adversos , Qualidade de Vida , Choque Hemorrágico/tratamento farmacológico
16.
Chemistry ; 29(50): e202300364, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37541431

RESUMO

A series of new conjugates comprised from a small synthetic antimicrobial peptide (AMP) and a siderophore-type vector component was designed and tested for activity on P. aeruginosa PAO1 and several genetically modified strains. As AMP, the well-established arginine-tryptophane combination K(RW)3 (P1) was chosen with an added lysine for siderophore attachment. This peptide is easy to prepare, modify, and possesses good anti-bacterial activity. On the vector part, we examined several moieties: (i) the natural siderophore deferoxamine (DFO); (ii) bidentate iron chelators based on the hydroxamate building block (4 a-c) ; (iii) the non-siderophore chelators deferasirox (DFX) and deferiprone-carboxylate (DFP-COOH). All conjugates were prepared by solid phase synthesis techniques and fully characterized by HPLC and mass spectrometry (including HR-MS). 55 Fe uptake assays indicate a receptor-mediated uptake for 4 a-c, DFP-COOH and DFO, which is dependent on the outer membrane transporter FoxA in the case of DFO. All conjugates showed increased antibacterial activity against P. aeruginosa compared to the parent peptide P1 alone when investigated in iron-depleted medium. MIC values were as low as 2 µM (for P1-DFP) on wild type P. aeruginosa. The activity of P1-DFO and P1-DFP was even better on genetically mutated strains unable to produce siderophores (down to 0.5 µM). Although the DFX vector on its own was not able to transport iron inside the bacterial cell as shown by 55 Fe uptake studies, the P1-DFX conjugate had excellent antibacterial activity compared to P1 (2 µM, and as low as 0.25 µM on a receptor-deficient strain unable to produce siderophores), suggesting that the conjugates were indeed recognized and internalized by an (unknown) transporter. Control experiments with an equimolar mixture of P1 and DFX confirm that the observed activity is intrinsic to vectorization. This work thus demonstrates the power of linking small AMPs covalently to siderophores for a new class of Trojan Horse antibiotics, with P1-DFP and P1-DFX being the most potent conjugates.


Assuntos
Pseudomonas aeruginosa , Sideróforos , Sideróforos/química , Ferro/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Membrana Transportadoras , Peptídeos , Proteínas de Transporte
17.
Ann N Y Acad Sci ; 1529(1): 33-41, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37594980

RESUMO

Combination chelation therapies are considered in transfusion-dependent thalassemia patients for whom monotherapy regimens have failed to achieve iron balance or intensification of iron chelation therapy is required for the rapid reduction of excess iron to avoid permanent organ damage. Combination chelation may provide a more flexible approach for individualizing chelation therapy, thereby improving tolerability, adherence, and quality of life. In principle, iron chelators can be combined with an infinite number of dosing regimens; these involve simultaneous or sequential exposure to the chelators on the same day or alternating the drugs on different days. Clinical studies have established the safety and efficacy of chelation combinations. However, real-life data with combination therapies indicate the significance of compliance for a meaningful reduction in iron overload compared to monotherapies.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Humanos , Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Deferiprona/uso terapêutico , Qualidade de Vida , Benzoatos/efeitos adversos , Triazóis , Piridonas , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/induzido quimicamente , Ferro , Quimioterapia Combinada
18.
Anal Chim Acta ; 1277: 341681, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37604616

RESUMO

Deferasirox (DEF) is essential for patients with thalassemia requiring long-term transfusion therapy. Tigecycline (TIGE) is a first-line drug for the clinical treatment of complex, severe bacterial infections. The two drugs can be coordinated to treat Pseudomonas aeruginosa infections. Easy and efficient techniques for monitoring these two drugs in biological samples are few. Metal-organic framework (Zn-MOF) prepared from zinc nitrate hexahydrate and dithioglycolic acid has a flower structure. Interestingly, Zn-MOF can cause DEF to aggregate on it and induce DEF luminescence. The principle may be that Zn-MOF limits the vibration and rotation of DEF to avoid its nonradiative jump, which triggers aggregation-induced emission (AIE) and exhibits intense fluorescence. Further investigation revealed that TIGE could decompose Zn-MOF, thus alleviating the inhibitory effect of Zn-MOF on DEF and reducing the fluorescence intensity of DEF@Zn-MOF. A DEF/TIGE detection biosensor was created based on the fluorescence "turn-on" effect of Zn-MOF on DEF and the fluorescence "turn-off" effect of TIGE on DEF@Zn-MOF. The proposed technique was subsequently used to identify DEF/TIGE levels in pharmaceuticals and human plasma. The mean values for the percentage of the labeled amount of DEF/TIGE in DEF dispersible tablets/TIGE injection were 104.5 and 104.9%, respectively. The detection limits for the fluorescence detection of DEF and TIGE were 3.6 and 1.2 nM, respectively. This fluorescence assay is the first application of MOF to the simultaneous detection of DEF and TIGE and has the advantages of rapid sensitivity and high selectivity, providing a new strategy for drug detection.


Assuntos
Estruturas Metalorgânicas , Humanos , Tigeciclina , Deferasirox , Zinco , Corantes , Preparações Farmacêuticas
19.
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
20.
Bull Cancer ; 110(11): 1176-1182, 2023 Nov.
Artigo em Francês | MEDLINE | ID: mdl-37543453

RESUMO

Iron overload (IO) is probably as toxic in elderly patients with low-risk myelodysplastic syndromes (MDS) as in young thalassemic patients. This impact is more difficult to demonstrate because of associated comorbidities. Cardiovascular disease increases vulnerability to the toxic effects of IO. In recent years, registry studies have shown a survival benefit of Iron Chelation Therapy (ICT) in these patients. These findings are now corroborated by an improvement in event-free survival in a single randomized study: the Telesto study. The EFS curves separate after two years of follow-up. This indicates inertia in the occurrence of complications. The benefits of ICT are also very slowly being revealed. It is possible to offer ICT to patients with transfusion-dependent MDS with a life expectancy of at least two years. In Telesto, patients had a serum ferritin (F) level of at least 1000ng/mL, recommendations using this F threshold as a trigger for chelation seem to be reinforced. It remains an open question whether chelation should be started earlier for effective suppression of IO-related oxidative stress. ICTs could be used in transfusion-dependent MDS patients with life expectancy greater than two years. including possibly higher risk patients responding to hypomethylating agents.


Assuntos
Sobrecarga de Ferro , Síndromes Mielodisplásicas , Humanos , Idoso , Quelantes de Ferro/uso terapêutico , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico , Transfusão de Sangue , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Intervalo Livre de Progressão
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