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Chemical Research in Toxicology Aug 2023Deferasirox (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...
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 and 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 -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.
Topics: Rats; Animals; Activation, Metabolic; Deferasirox; Liver; Hepatocytes; Microsomes, Liver; Acetylcysteine; Glutathione
PubMed: 37435843
DOI: 10.1021/acs.chemrestox.2c00416 -
Journal of Blood Medicine 2023Chronic kidney disease (CKD) is a major global health concern, affecting millions of people worldwide. The progressive decline in kidney function often necessitates... (Review)
Review
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.
PubMed: 38047247
DOI: 10.2147/JBM.S415604 -
International Journal of Biological... Dec 2023In July 2022, the World Health Organization announced monkeypox as a public health emergency of international concern (PHEIC), and over 85,000 global cases have been...
In July 2022, the World Health Organization announced monkeypox as a public health emergency of international concern (PHEIC), and over 85,000 global cases have been reported currently. However, preventive and therapeutic treatments for the monkeypox virus (MPXV) remain limited. MPXV mRNA cap N7 methyltransferase (MTase) is composed of two subunits (E1 C-terminal domain (E1) and E12) which are essential for the replication of MPXV. Here, we solved a 2.16 Å crystal structure of E12. We also docked the D1 of the vaccinia virus (VACV) corresponding to the E1 in MPXV with E12 and found critical residues at their interface. These residues were further used for drug screening. After virtual screening, the top 347 compounds were screened out and a list of top 20 potential MPXV E12 inhibitors were discovered, including Rutin, Quercitrin, Epigallocatechin, Rosuvastatin, 5-hydroxy-L-Tryptophan, and Deferasirox, etc., which were potential E12 inhibitors. Taking the advantage of the previously unrecognized special structure of MPXV MTase composing of E1 and E12 heterodimer, we screened for inhibitors targeting MTase for the first time based on the interface between the heterodimer of MPXV MTase. Our study may provide insights into the development of anti-MPXV drugs.
Topics: RNA, Messenger; Methyltransferases; Monkeypox virus; Guanine
PubMed: 37866584
DOI: 10.1016/j.ijbiomac.2023.127565 -
Phytomedicine : International Journal... Jul 2024Myoglobin (Mb) induced death of renal tubular epithelial cells (RTECs) is a major pathological factor in crush syndrome-related acute kidney injury (CS-AKI). It is...
BACKGROUND
Myoglobin (Mb) induced death of renal tubular epithelial cells (RTECs) is a major pathological factor in crush syndrome-related acute kidney injury (CS-AKI). It is unclear whether ferroptosis is involved and could be a target for treatment.
PURPOSE
This study aimed to evaluate the potential therapeutic effects of combining the natural small molecule rosemarinic acid (RA) and the iron chelator deferasirox (Dfe) on CS-AKI through inhibition of ferroptosis.
METHODS
Sequencing data were downloaded from the GEO database, and differential expression analysis was performed using the R software limma package. The CS-AKI mouse model was constructed by squeezing the bilateral thighs of mice for 16 h with 1.5 kg weight. TCMK1 and NRK-52E cells were induced with 200 μM Mb and then treated with RA combined with Dfe (Dfe + RA, both were 10 μM). Functional and pathological changes in mouse kidney were evaluated by glomerular filtration rate (GFR) and HE pathology. Immunofluorescence assay was used to detect Mb levels in kidney tissues. The expression levels of ACSL4, GPX4, Keap1, and Nrf2 were analyzed by WB.
RESULTS
We found that AKI mice in the GSE44925 cohort highly expressed the ferroptosis markers ACSL4 and PTGS2. CS-AKI mice showed a rapid decrease in GFR, up-regulation of ACSL4 expression in kidney tissue, and down-regulation of GPX4 expression, indicating activation of the ferroptosis pathway. Mb was found to deposit in renal tubules, and it has been proven to cause ferroptosis in TCMK1 and NRK-52E cells in vitro. We found that Dfe had a strong iron ion scavenging effect and inhibited ACSL4 expression. RA could disrupt the interaction between Keap1 andNrf2, stabilize Nrf2, and promote its nuclear translocation, thereby exerting antioxidant effects. The combination of Dfe and RA effectively reversed Mb induced ferroptosis in RTECs.
CONCLUSION
In conclusion, we found that RA combined with Dfe attenuated CS-AKI by inhibiting Mb-induced ferroptosis in RTECs via activating the Nrf2/Keap1 pathway.
Topics: Animals; Ferroptosis; Kelch-Like ECH-Associated Protein 1; NF-E2-Related Factor 2; Acute Kidney Injury; Depsides; Mice; Deferasirox; Rosmarinic Acid; Male; Cinnamates; Disease Models, Animal; Iron Chelating Agents; Signal Transduction; Cell Line; Mice, Inbred C57BL
PubMed: 38704914
DOI: 10.1016/j.phymed.2024.155700 -
British Journal of Haematology May 2024Iron overload from repeated transfusions has a negative impact on cardiac function, and iron chelation therapy may help prevent cardiac dysfunction in... (Randomized Controlled Trial)
Randomized Controlled Trial
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.
Topics: Humans; Deferasirox; Myelodysplastic Syndromes; Male; Female; Iron Chelating Agents; Middle Aged; Aged; Iron Overload; Prospective Studies; Benzoates; Heart Failure; Transfusion Reaction; Echocardiography; Adult; Aged, 80 and over; Triazoles; Blood Transfusion
PubMed: 38343073
DOI: 10.1111/bjh.19316 -
Clinical and Translational Science Mar 2024Administration of oral medicinal products as crushed tablets or open capsules is an important delivery option for patients suffering from dysphagia. To obtain full... (Review)
Review
Administration of oral medicinal products as crushed tablets or open capsules is an important delivery option for patients suffering from dysphagia. To obtain full interchangeability of generics with the original products, demonstration of bioequivalence (BE) between both products administered as crushed tablets/open capsules was required for poorly soluble product by European Medicines Agency (EMA) at the time of development of our rivaroxaban and deferasirox generic products. We present the results of two BE studies with modified administration of these products, which compared relative bioavailability between generic and reference products. In the rivaroxaban study, the test product was administered as a capsule sprinkled on and mixed with applesauce, whereas the reference tablet was crushed and administered with applesauce under fed conditions. In the deferasirox study, both treatments were administered as crushed tablets under fasting conditions. Both studies applied a two-way crossover design and were conducted after a single-dose in healthy volunteers. The 90% confidence interval of the geometric mean ratio area under the analyte concentration versus time curve, from time zero to the time of the last measurable analyte concentration and maximum measured analyte concentration over the sampling period of the test to reference ratio were 103.36-110.37% and 97.98-108.45% for rivaroxaban, respectively, and 96.69-107.29% and 94.19-109.45% for deferasirox, respectively. Thus, the BE criteria (80.00-125.00%) were met in both studies which demonstrated that bioavailability was not affected when the test and reference products were administered in the form of crushed tablet/open capsule. These results support the argument of redundancy of crushed product studies for poorly soluble drugs, which is in line with the currently revised position of the EMA on this topic.
Topics: Humans; Therapeutic Equivalency; Rivaroxaban; Deferasirox; Administration, Oral; Tablets; Drugs, Generic
PubMed: 38511529
DOI: 10.1111/cts.13752 -
Annals of the New York Academy of... Feb 2024Health-related quality of life (HRQOL) is a patient-reported outcome that assesses the impact of a disease or illness on different domains of a patient's life. Different... (Review)
Review
Health-related quality of life (HRQOL) is a patient-reported outcome that assesses the impact of a disease or illness on different domains of a patient's life. Different general and disease-specific measures can be used to evaluate HRQOL. This article aimed to summarize the evidence for HRQOL among patients with transfusion-dependent (TDT) and non-transfusion-dependent thalassemia (NTDT). We included HRQOL data related to standard therapy with blood transfusions, iron chelation, and/or luspatercept in TDT and NTDT, as well as curative therapies for TDT, including hematopoietic stem cell transplant (HSCT) and gene therapy. Patients with thalassemia had worse HRQOL scores compared to the general population, and chronic pain was seen to increase in frequency and severity over time with age. NTDT patients reported worse physical health and functioning, mental health, general health, and vitality than TDT patients. However, TDT patients reported worse pain, change in health, and social support than NTDT. Most therapies improved overall HRQOL among thalassemia patients. Deferasirox, an oral iron chelator, was associated with more HRQOL benefits compared to deferoxamine, an intravenous iron chelator. Luspatercept showed clinically meaningful improvement in physical functioning among TDT and NTDT. Furthermore, HSCT and gene therapy were associated with better physical, emotional, and mental domains scores.
Topics: Humans; Quality of Life; Thalassemia; Iron Chelating Agents; Blood Transfusion; Chronic Pain; Iron Overload
PubMed: 38270933
DOI: 10.1111/nyas.15100 -
Chemistry (Weinheim An Der Bergstrasse,... Sep 2023A 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...
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) (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). 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 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.
Topics: Siderophores; Pseudomonas aeruginosa; Iron; Anti-Bacterial Agents; Membrane Transport Proteins; Peptides; Carrier Proteins
PubMed: 37541431
DOI: 10.1002/chem.202300364 -
International Journal of Molecular... Apr 2024The supply and control of iron is essential for all cells and vital for many physiological processes. All functions and activities of iron are expressed in conjunction... (Review)
Review
The supply and control of iron is essential for all cells and vital for many physiological processes. All functions and activities of iron are expressed in conjunction with iron-binding molecules. For example, natural chelators such as transferrin and chelator-iron complexes such as haem play major roles in iron metabolism and human physiology. Similarly, the mainstay treatments of the most common diseases of iron metabolism, namely iron deficiency anaemia and iron overload, involve many iron-chelator complexes and the iron-chelating drugs deferiprone (L1), deferoxamine (DF) and deferasirox. Endogenous chelators such as citric acid and glutathione and exogenous chelators such as ascorbic acid also play important roles in iron metabolism and iron homeostasis. Recent advances in the treatment of iron deficiency anaemia with effective iron complexes such as the ferric iron tri-maltol complex (feraccru or accrufer) and the effective treatment of transfusional iron overload using L1 and L1/DF combinations have decreased associated mortality and morbidity and also improved the quality of life of millions of patients. Many other chelating drugs such as ciclopirox, dexrazoxane and EDTA are used daily by millions of patients in other diseases. Similarly, many other drugs or their metabolites with iron-chelation capacity such as hydroxyurea, tetracyclines, anthracyclines and aspirin, as well as dietary molecules such as gallic acid, caffeic acid, quercetin, ellagic acid, maltol and many other phytochelators, are known to interact with iron and affect iron metabolism and related diseases. Different interactions are also observed in the presence of essential, xenobiotic, diagnostic and theranostic metal ions competing with iron. Clinical trials using L1 in Parkinson's, Alzheimer's and other neurodegenerative diseases, as well as HIV and other infections, cancer, diabetic nephropathy and anaemia of inflammation, highlight the importance of chelation therapy in many other clinical conditions. The proposed use of iron chelators for modulating ferroptosis signifies a new era in the design of new therapeutic chelation strategies in many other diseases. The introduction of artificial intelligence guidance for optimal chelation therapeutic outcomes in personalised medicine is expected to increase further the impact of chelation in medicine, as well as the survival and quality of life of millions of patients with iron metabolic disorders and also other diseases.
Topics: Humans; Iron Overload; Iron Chelating Agents; Anemia, Iron-Deficiency; Iron; Animals; Deferiprone
PubMed: 38731873
DOI: 10.3390/ijms25094654 -
Annals of Hematology Jun 2024A 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...
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.
Topics: Humans; Female; Middle Aged; Ceruloplasmin; Iron Metabolism Disorders; Magnetic Resonance Imaging; Neurodegenerative Diseases; Liver; Ferritins; Iron; Diagnosis, Differential; Iron Overload; Deferasirox
PubMed: 38637332
DOI: 10.1007/s00277-024-05743-7