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In the present study, three complexes with nickel central metal and with general formula [Ni(L)2]; where L is 3-hydroxy flavone (HLf), deferiprone (HLd) and maltol (HLm); synthesized and characterized by Infrared spectroscopy, mass spectroscopy, and elemental analysis. Studies have shown three ligands that used in this study, after coordination to metals, prevent the proliferation of cancer cells, so the anti-cancer property of the synthesized compounds was investigated by MTT assay against HeLa, MCF-7, MDA-MB-231, NALM-6, Neuro-2a, and L929; cell lines and cisplatin was used as a control. Furthermore, we investigate the ability of 3-hydroxy flavone (HLf), deferiprone (HLd) and maltol (HLm) chelating with nickel (II) metal ion using density functional theory in both gas and solvent phases, Through the M062x/6-311++G(d, P) surface and Gaussian09 calculation package. Structural analysis shows that all three chelators are bonded to Ni2+ via oxygen atoms of hydroxyl, and carbonyl groups. The receptor-acceptor interactions represent the effective charge transfer from the oxygen atoms of the chelators to the metal ions. The quantum theory of atoms in molecular analysis reveals noncovalent interactions, and it should be noted that mainly, electrostatic interactions play an important role in the formation of Ni-metal complexes. The TD-DFT study was performed to investigate the main electron transfer. ELF and LOL analyzes were also performed to confirm the results obtained through QTAIM analysis. Interaction energies and metal ion affinity were calculated for [Ni(L)2] complexes, and the results showed that we observed a very exothermic reaction during the chelating process. Natural bond analysis (NBO) was performed to understand the charge transfer in the studied complexes. The results confirmed that the selected chelators are suitable chelating agents for the treatment of nickel.

Raffaele Nuzzi,1 Giada Geronazzo,1,2 Federico Tridico,1 Alessia Nuzzi,3 Paolo Caselgrandi,1 Antonio Giulio Piga4 1Eye Clinic Section, Department of Surgical Sciences, University of Turin, Turin, Italy; 2Regional Reference Centre for Diagnosis and Cure of Hemoglobinopathies, S. Luigi Gonzaga University Hospital, University of Turin, Orbassano (TO), Italy; 3Department of Clinical Sciences and Community Health, Eye Clinic San Giuseppe Hospital, IRCCS Multimedica, University of Milan, Milan, Italy; 4Head of Regional Reference Centre for Diagnosis and Cure of Hemoglobinopathies, S. Luigi Gonzaga University Hospital, University of Turin, Orbassano (TO), ItalyCorrespondence: Raffaele NuzziEye Clinic Section, Department of Surgical Sciences, University of Turin, Via Cherasco 23, Turin, 10126, ItalyEmail prof.nuzzi_raffaele@hotmail.itBackground: The aim of this study is to evaluate eye structures and function in patients receiving iron chelating therapy and to assess whether a correlation exists between the onset of ocular alterations and the intake of iron chelating drugs.Methods: A prospective cohort study was performed. Eighty-eight patients, composed of children and adults with thalassemia major (TM) who are taking or had taken iron chelating drugs (deferoxamine, deferiprone or deferasirox), have been initially enrolled in the study. The final sample featured 80 patients, including 18 children and 62 adults. These subjects received an eye examination to evaluate intraocular pressure (IOP), best corrected visual acuity (BCVA), the presence of refractive defects, cornea, anterior chamber, lens, fundus oculi, visual field and mean retinal nerve fiber layer (RNFL) thickness. Logistic regression model analysis was performed in order to assess any correlation. In addition, a literature search regarding the relation between iron chelating drugs and ocular adverse events was carried out to compare the results obtained with the evidence in the literature.Results: Logistic regression did not report a significant correlation between the intake of iron chelating drugs and the onset of anterior ocular segment alterations, lens opacities, retinal diseases, optical neuropathies, astigmatism, visual field and RNFL thickness defects. Logistic regression returned a statistically significant correlation between myopia and iron chelation therapy (p-value 0.04; OR 1.05) and also between presbyopia and total duration of therapy with deferoxamine (p-value 0.03; OR 1.21). Although intraocular pressure levels remained within the normal range, a significant correlation with the length of deferoxamine therapy has been found (p-value 0.002; association coefficient − 0.12). A negative correlation between deferiprone and presbyopia has also been observed.Conclusion: Iron chelation therapy is not associated with severe visual function alterations. Limitation of deferoxamine treatment can help prevent ocular complications. Deferiprone and/or deferasirox may be preferable, especially in patients over age 40 years.Keywords: iron chelation, ocular adverse effects, deferiprone, deferasirox, deferoxamine

We conducted a retrospective cohort study on 663 transfusion-dependent β-thalassemia patients receiving the same iron chelation monotherapy with deferoxamine, deferiprone, or deferasirox for up to 10 years (median age 31.8 years, 49.9 % females). Patients on all three iron chelators had a steady and significant decline in serum ferritin over the 10 years (median deferoxamine: −170.7 ng/mL, P = 0.049, deferiprone: −236.7 ng/mL, P = 0.001; deferasirox: −323.7 ng/mL, P < 0.001) yet had no significant change in liver iron concentration or cardiac T2*; while noting that patients generally had low hepatic and cardiac iron levels at study start. Median absolute, relative, and normalized changes were generally comparable between the three iron chelators. Patients receiving deferasirox had the highest morbidity and mortality-free survival probability among the three chelators, although the difference was only statistically significant when compared with deferoxamine (P = 0.037). On multivariate Cox regression analysis, there was no significant association between iron chelator type and the composite outcome of morbidity or mortality. In a real-world setting, there is comparable long-term iron chelation effectiveness between the three available iron chelators for patients with mild-to-moderate iron overload. [ABSTRACT FROM AUTHOR]

The historical insights and background of the discovery, development and clinical use of deferiprone (L1) and the maltol–iron complex, which were discovered over 40 years ago, highlight the difficulties, complexities and efforts in general orphan drug development programs originating from academic centers. Deferiprone is widely used for the removal of excess iron in the treatment of iron overload diseases, but also in many other diseases associated with iron toxicity, as well as the modulation of iron metabolism pathways. The maltol–iron complex is a recently approved drug used for increasing iron intake in the treatment of iron deficiency anemia, a condition affecting one-third to one-quarter of the world’s population. Detailed insights into different aspects of drug development associated with L1 and the maltol–iron complex are revealed, including theoretical concepts of invention; drug discovery; new chemical synthesis; in vitro, in vivo and clinical screening; toxicology; pharmacology; and the optimization of dose protocols. The prospects of the application of these two drugs in many other diseases are discussed under the light of competing drugs from other academic and commercial centers and also different regulatory authorities. The underlying scientific and other strategies, as well as the many limitations in the present global scene of pharmaceuticals, are also highlighted, with an emphasis on the priorities for orphan drug and emergency medicine development, including the roles of the academic scientific community, pharmaceutical companies and patient organizations.

Lead (Pb) is a highly toxic heavy metal that has deleterious effects on the central nervous system. This study aimed to investigate the effects of salinomycin (Sal) and deferiprone (DFP) on brain morphology and on the content of some essential elements in Pb-exposed mice. Adult male Institute of Cancer Research (ICR) mice were exposed to a daily dose of 80 mg/kg body weight ( b.w.) Pb(II) nitrate for 14 days and subsequently treated with Sal (16 mg/kg b.w.) or DFP (19 mg/kg b.w.) for another 14 days. At the end of the experimental protocol, the brains were processed for histological and inductively coupled plasma mass spectrometry (ICP-MS) analyses. Pb exposure resulted in a 50-fold increase in Pb concentration, compared with controls. Magnesium (Mg) and phosphorus (P) were also significantly increased by 22.22% and 17.92%, respectively. The histological analysis of Pb-exposed mice revealed brain pathological changes with features of neuronal necrosis. Brain Pb level remained significantly elevated in Sal- and DFP-administered groups (37-fold and 50-fold, respectively), compared with untreated controls. Treatment with Sal significantly reduced Mg and P concentrations by 22.56% and 18.38%, respectively, compared with the Pb-exposed group. Administration of Sal and DFP ameliorated brain injury in Pb-exposed mice and improved histological features. The results suggest the potential application of Sal and DFP for treatment of Pb-induced neurotoxicity.

Lead (Pb) exposure induces severe nephrotoxic effects in humans and animals. Herein, we compare the effects of two chelating agents, salinomycin and deferiprone, on Pb-induced renal alterations in mice and in the homeostasis of essential elements. Adult male mice (Institute of Cancer Research (ICR)) were randomized into four groups: control (Ctrl)—untreated mice administered distilled water for 28 days; Pb-exposed group (Pb)—mice administered orally an average daily dose of 80 mg/kg body weight (BW) lead (II) nitrate (Pb(NO3)2) during the first two weeks of the experimental protocol followed by the administration of distilled water for another two weeks; salinomycin-treated (Pb + Sal) group—Pb-exposed mice, administered an average daily dose of 16 mg/kg BW salinomycin for two weeks; deferiprone-treated (Pb + Def) group—Pb-exposed mice, administered an average daily dose of 20 mg/kg BW deferiprone for 14 days. The exposure of mice to Pb induced significant accumulation of the toxic metal in the kidneys and elicited inflammation with leukocyte infiltrations near the glomerulus. Biochemical analysis of the sera revealed that Pb significantly altered the renal function markers. Pb-induced renal toxicity was accompanied by a significant decrease in the endogenous renal concentrations of phosphorous (P), calcium (Ca), copper (Cu) and selenium (Se). In contrast to deferiprone, salinomycin significantly improved renal morphology in Pb-treated mice and decreased the Pb content by 13.62% compared to the Pb-exposed group. There was also a mild decrease in the renal endogenous concentration of magnesium (Mg) and elevation of the renal concentration of iron (Fe) in the salinomycin-treated group compared to controls. Overall, the results demonstrated that salinomycin is a more effective chelating agent for the treatment of Pb-induced alterations in renal morphology compared to deferiprone. [ABSTRACT FROM AUTHOR]

The aim of this study is the evaluation of the safety and the efficacy of long-term combination therapy deferasirox plus desferrioxamine and deferasirox plus deferiprone in a large group of transfusion-dependent thalassemia patients with high values of serum ferritin and/or magnetic resonance, indicative of severe liver and cardiac iron accumulation. Sixteen adults with transfusion-dependent thalassemia were treated simultaneously with deferasirox plus desferrioxamine, while another 42 patients (seven children) were treated with deferasirox plus deferiprone. The hepatic and cardiac iron overload was assessed prior to treatment and then annually with magnetic resonance imaging, and the serum ferritin was measured monthly. Adverse events were checked at each transfusion visit. The safety of both the combinations was consistent with established monotherapies. Both treatments were able to decrease the serum ferritin and liver iron concentration over time, depending on the level of compliance with therapy. Cardiac iron measured as R2* did not significantly change in patients treated with deferasirox plus desferrioxamine. Most patients with MRI indicative of myocardial siderosis at the beginning of treatment reached normal values of cardiac iron at the last determination if treated with deferasirox plus desferrioxamine. The greatest limitation of these therapies was low patient adherence to the two drugs, which is not surprising considering that the need for an intensive chelation is generally linked to previous issues of compliance. [ABSTRACT FROM AUTHOR]

Patients with sickle cell disease (SCD) who undergo repeated blood transfusions often develop iron overload. Deferiprone (Ferriprox®) is an oral iron chelator indicated for the treatment of transfusional iron overload due to thalassemia syndromes and has been recently approved as a treatment for iron overload in adult and pediatric patients with SCD and other anemias. The present study aims to characterize the pharmacokinetic (PK) profile of deferiprone (DFP) in adult subjects with SCD. In this phase I, open-label study, subjects with SCD were administered a single 1500 mg dose of DFP. Blood and urine samples were collected for PK assessments of DFP and its main metabolite, deferiprone 3-O-glucuronide (DFP-G). Eight subjects were enrolled and completed the study. Following drug administration, serum levels of DFP and DFP-G rose to maximum concentrations at 1.0 and 2.8 h post-dose, respectively. The half-lives of DFP and DFP-G were 1.5 and 1.6 h, respectively. The majority of administered drug was metabolized and excreted as DFP-G, with less than 4% excreted unchanged in urine up to 10 h post-dose. Subjects received a safety assessment 7 (± 3) days post-dose. Two subjects reported mild adverse events unrelated to the study drug, and no other safety concerns were reported. The PK profile of DFP in SCD subjects is consistent with previous reports in healthy adult volunteers, suggesting no special dosing adjustments are indicated for this population. These findings provide valuable insight for treating iron overload in patients with SCD, who have limited chelation therapy treatment options (trial registration number: NCT01835496, date of registration: April 19, 2013). [ABSTRACT FROM AUTHOR]

Compounds with more than one molecule in the crystallographic asymmetric unit (Z′ > 1) display a noticeably stronger propensity to form cocrystals. Deferiprone is an anti‐thalassemia drug known to exhibit polymorphic behaviour. Previously, three polymorphs were reported out of which one of them exhibited Z′ > 1. In the present manuscript, a fourth polymorph of deferiprone was identified and it also possessed Z′ > 1. All the four polymorphs showed similar hydrogen bonding features and differed in crystal packing. The ability of deferiprone to crystallize as Z′ > 1 prompted us to investigate the hydrogen bonding and synthon variation upon cocrystallization of deferiprone with hydroxyl‐group‐containing coformers such as catechol, hydroquinone, phloroglucinol, resorcinol and pyrogallol. Crystallization attempts along with PXRD analysis aided in obtaining 11 new cocrystal structures which involve different stoichiometric cocrystals and some polymorphs. Synthon analysis, crystal packing as well as thermal behaviour were assessed and compared. The presence of multiple phases in each cocrystal system in its respective bulk powders was identified and quantified using PXRD and Rietveld analysis. Homosynthons were observed in three co‐crystal systems, while a heterosynthon was observed in five systems. The combination of both homo‐ and heterosynthon was observed in three cocrystal systems. The phase transformation events were observed in most of the systems. In nine co‐crystal systems, the melting points were observed intermediate between those of the API and the coformers. [ABSTRACT FROM AUTHOR]

Deferiprone (DFP) is a metal chelating agent generally used to treat patients with thalassaemia, due to iron overload in clinical settings. Studies have revealed that long-term use of DFP can induce hepatotoxicity, however, mechanisms of its toxic action remain unclear. The present studies are aimed to characterize the reactive metabolite of DFP, to define the metabolic pathway, and to determine the P450 enzymes participating in the bioactivation. A demethylation metabolite (M1) was observed in rat liver microsomal incubations. Additionally, a glutathione (GSH) conjugate (M2) and an N-acetylcysteine (NAC) conjugate (M3) were detected in microsomal incubations fortified with DFP and GSH/NAC. Biliary M2 and urinary M3 were respectively found in animals administered DFP. CYP2A6 enzyme dominated the catalysis to bioactivate DFP. [ABSTRACT FROM AUTHOR]

Background & aim: Thalassemia syndromes are the most common inherited hemoglobinopathies in the world characterized by various degrees of defective production of the alpha or beta globin chains. Iran is one of the countries located on the thalassemia belt and therefore thalassemia syndromes have a significant importance in our country. The most important mainstay of treatment in beta thalassemia is packed red blood cell transfusion. Thalassemic patients need lifelong transfusions and the consequence of these repeated transfusions is iron accumulation in different organs, such as heart, liver and endocrine gland. Methods: In this review, an electronic search was performed in databases of PubMed, Google Scholar, Scopus and Science Direct within English literature (from January 2000 to January 2020). In this search 148 articles were found. The title, abstract and full text of all documents identified and those describing iron chelator drugs in thalassemic patients were finally selected. Overall, 124 of which were excluded because they did not correlate with the main topic or were duplicate. Results: The oldest iron chelator drug is deferoxamine which was administered via subcutaneous or intravenous injection. The first oral iron chelator is deferiprone and the second drug, deferasirox. In recent years, deferasirox coated tablets with the brand name Jadenu have been launched, which no longer need to be dissolved in water and has gained special popularity among thalassemia patients. Conclusion: Iron overload due to repeated transfusions results in organ dysfunction and finally heart failure, liver cirrhosis and multiple endocrinopathies develops. In order to prevent iron accumulation in vital organs, consumption of iron chelator drugs is necessary. Without the use of these drugs, the survival of thalassemia patients will be significantly reduced. Therefore, familiarity with iron chelator drugs has particular importance. Keywords: Thalassemia, Iron overload, Iron chelation, Deferoxamine, Deferiprone, Deferasirox

Thalassemia patients are susceptible to both iron overload and thromboembolism. Deferiprone is an iron chelator that shows an antiplatelet activity and thus may alleviate platelet hyperactivation in thalassemia. Therefore, this study aimed to characterize the inhibitory effects and mechanisms of deferiprone on normal human platelets. The results illustrated that deferiprone inhibited platelet aggregation at the iron chelating concentrations (0.08–0.25 mmol/l). Deferiprone inhibited human platelet aggregation stimulated by arachidonic acid and ADP more potently than epinephrine and collagen, with the IC50 of 0.24 mmol/l and 0.25 mmol/l vs. 3.36 mmol/l and 3.73 mmol/l, respectively. Interestingly, deferiprone significantly inhibited COX-1 activity, with the IC50 of 0.33 mmol/l, and slightly increased cAMP level at the high concentration of 4 mmol/l. Moreover, the results from molecular docking showed that deferiprone interacted closely with key residues in the peroxidase active site of COX-1. These results suggested that deferiprone possessed antiplatelet activity mainly through the inhibition of COX-1 activity.

Abstract Background Aceruloplasminemia is a rare genetic iron overload disorder, characterized by progressive neurological manifestations. The effects of iron chelation on neurological outcomes have only been described in case studies, and are inconsistent. Aggregated case reports were analyzed to help delineate the disease-modifying potential of treatment. Methods Data on clinical manifestations, treatment and neurological outcomes of treatment were collected from three neurologically symptomatic Dutch patients, who received deferiprone with phlebotomy as a new therapeutic approach, and combined with other published cases. Neurological outcomes of treatment were compared between patients starting treatment when neurologically symptomatic and patients without neurological manifestations. Results Therapeutic approaches for aceruloplasminemia have been described in 48 patients worldwide, including our three patients. Initiation of treatment in a presymptomatic stage of the disease delayed the estimated onset of neurological manifestations by 10 years (median age 61 years, SE 5.0 vs. median age 51 years, SE 0.6, p = 0.001). Although in 11/20 neurologically symptomatic patients neurological manifestations remained stable or improved during treatment, these patients were treated significantly shorter than patients who deteriorated neurologically (median 6 months vs. median 43 months, p = 0.016). Combined iron chelation therapy with deferiprone and phlebotomy for up to 34 months could be safely performed in our patients without symptomatic anemia (2/3), but did not prevent further neurological deterioration. Conclusions Early initiation of iron chelation therapy seems to postpone the onset of neurological manifestations in aceruloplasminemia. Publication bias and significant differences in duration of treatment should be considered when interpreting reported treatment outcomes in neurologically symptomatic patients. Based on theoretical grounds and the observed long-term safety and tolerability in our study, we recommend iron chelation therapy with deferiprone in combination with phlebotomy for aceruloplasminemia patients without symptomatic anemia.

Objectives: Prooxidant properties of iron-binding hydroxypyridone compounds including deferiprone and mimosine were analyzed. Methods: Hydroxypyridone/iron-dependent production of reactive oxygen species was evidenced by the inactivation of aconitase, the most sensitive enzyme to oxidative stress in permeabilized yeast cells. Results and Discussion: Deferiprone and mimosine produced reactive oxygen species in the presence of ferrous sulfate. The inactivation required sodium azide the inhibitor of catalase, and addition of TEMPOL, a scavenger of superoxide radical, protected aconitase from the inactivation, suggesting that the superoxide radical produced from the hydroxypyridone/iron complex is responsible for the inactivation of aconitase. A principal role of superoxide radical was further supported by the finding that the hydroxypyridone/iron complex can inactivate aconitase in the presence of cyanide the inhibitor of superoxide dismutase. Deferiprone and mimosine stimulated the Fe2+ oxidation, resulting in the one-electron reduction of oxygen to form superoxide anion, which can inactivate aconitase by oxidizing the prosthetic iron-sulfur cluster. Mimosine further stimulated the ascorbate/iron-dependent formation of 8-hydroxy-2′-deoxyguanosine in DNA. Conclusion: Biological toxicity of mimosine and deferiprone reported previously can be accounted for by the prooxidant properties of hydroxypyridone compounds: coordination complex with iron generates reactive oxygen species resulting in the disturbance of mitochondrial energy metabolism and DNA damage.

The oxidative status of twenty-three β-thalassemia/hemoglobin E patients was evaluated after administration of 75 mg/kg deferiprone (GPO-L-ONE®) divided into 3 doses daily for 12 months. Serum ferritin was significantly decreased; the median value at the initial and final assessments was 2842 and 1719 ng/mL, respectively. Progressive improvement with significant changes in antioxidant enzyme activity, including plasma paraoxonase (PON) and platelet-activating factor acetylhydrolase (PAF-AH), and in antioxidant enzymes in red blood cells (glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD)) were observed at 3–6 months of treatment. The levels of total GSH in red blood cells were significantly increased at the end of the study. Improved red blood cell membrane integrity was also demonstrated using the EPR spin labeling technique. Membrane fluidity at the surface and hydrophobic regions of the red blood cell membrane was significantly changed after 12 months of treatment. In addition, a significant increase in hemoglobin content was observed (6.6 ± 0.7 and 7.5 ± 1.3 g/dL at the initial assessment and at 6 months, respectively). Correlations were observed between hemoglobin content, membrane fluidity and antioxidant enzymes in red blood cells. The antioxidant activity of deferiprone may partly be explained by progressive reduction of redox active iron that catalyzes free radical reactions, as demonstrated by the EPR spin trapping technique. In conclusion, iron chelation therapy with deferiprone notably improved the oxidative status in thalassemia, consequently reducing the risk of oxidative-related complications. Furthermore, the improvement in red blood cell quality may improve the anemia situation in patients.

Multiple System Atrophy (MSA) is a rare neurodegenerative synucleinopathy which leads to severe disability followed by death within 6–9 years of symptom onset. There is compelling evidence suggesting that biological trace metals like iron and copper play an important role in synucleinopathies like Parkinson's disease and removing excess brain iron using chelators could slow down the disease progression. In human MSA, there is evidence of increased iron in affected brain regions, but role of iron and therapeutic efficacy of iron-lowering drugs in pre-clinical models of MSA have not been studied.We studied age-related changes in iron metabolism in different brain regions of the PLP-αsyn mice and tested whether iron-lowering drugs could alleviate disease phenotype in aged PLP-αsyn mice. Iron content, iron-ferritin association, ferritin protein levels and copper-ceruloplasmin association were measured in prefrontal cortex, putamen, substantia nigra and cerebellum of 3, 8, and 20-month-old PLP-αsyn and age-matched non-transgenic mice. Moreover, 12-month-old PLP-αsyn mice were administered deferiprone or ceruloplasmin or vehicle for 2 months. At the end of treatment period, motor testing and stereological analyses were performed.We found iron accumulation and perturbed iron-ferritin interaction in substantia nigra, putamen and cerebellum of aged PLP-αsyn mice. Furthermore, we found significant reduction in ceruloplasmin-bound copper in substantia nigra and cerebellum of the PLP-αsyn mice. Both deferiprone and ceruloplasmin prevented decline in motor performance in aged PLP-αsyn mice and were associated with higher neuronal survival and reduced density of α-synuclein aggregates in substantia nigra.This is the first study to report brain iron accumulation in a mouse model of MSA. Our results indicate that elevated iron in MSA mice may result from ceruloplasmin dysfunction and provide evidence that targeting iron in MSA could be a viable therapeutic option.

Nancy Olivieri is a senior haematologist and professor at the University of Toronto, Canada. In the early 1990s, she was conducting investigator-initiated research of an experimental drug, deferiprone, in children with thalassaemia, for which a pharmaceutical company, Apotex, started giving some supplemental support. In the course of her work, Dr Olivieri found that deferiprone might not be very effective and was also possibly toxic. When she signalled her intent to disclose the risks to participants, the trials were immediately shut down and she was threatened with "all legal remedies" should she disclose her concerns. This led to 18 years of attacks from the CEO of Apotex as well as fabricated charges and harassment from the University and the Hospital for Sick Children where she worked.

A key aspect for the applicability of 89 Zr-radioimmunoconjugates is inert modification and radiolabeling. The two commercially available bifunctional variants of the siderophore desferrioxamine (DFO), Fe-DFO-N-suc-TFP-ester and p-NCS-Bz-DFO, are most often used for clinical 89 Zr-immuno-PET. The use of Fe-DFO-N-suc-TFP-ester is advantageous with regard to higher radiolysis stability and more facile assessment of radiochemical purity as well as chelator-to-mAb ratio. However, not all mAbs withstand the Fe-removal step at relatively low pH (4-4.5) using EDTA, which is needed after conjugation to allow 89 Zr labeling. In this study, it was investigated whether hydroxybenzyl ethylenediamine (HBED) or the clinically approved deferiprone (DFP) can serve as an alternative for EDTA to establish a pH-independent mild method for Fe-removal and thereby broaden the applicability of Fe-DFO-N-suc-TFP-ester. Carrier-added [ 59 Fe]Fe-DFO-N-suc-TFP-ester was used for mAb modification to enable direct tracking of the Fe-removal efficiency under various conditions. Whereas incomplete Fe-removal with HBED was observed at pH 5 or higher, Fe-removal with DFP was possible at a broad pH range (4-9). This provides a mild, pH-independent method for Fe-removal, improving the applicability and attractiveness of Fe-DFO-N-suc-TFP-ester for 89 Zr-mAb preparation., (© 2024 The Authors. Journal of Labelled Compounds and Radiopharmaceuticals published by John Wiley & Sons Ltd.)

The chelating thiol dimercaptosuccinate (DMSA) and the traditional agent D-penicillamine (PSH) are effective in enhancing the urinary excretion of copper (Cu) and lead (Pb) in poisoned individuals. However, DMSA, PSH, EDTA (ethylenediamine tetraacetate), and deferoxamine (DFOA) are water-soluble agents with limited access to the central nervous system (CNS). Strategies for mobilization of metals such as manganese (Mn), iron (Fe), and Cu from brain deposits may require the combined use of two agents: one water-soluble agent to remove circulating metal into urine, in addition to an adjuvant shuttler to facilitate the brain-to-blood mobilization. The present review discusses the chemical basis of metal chelation and the ligand exchange of metal ions. To obtain increased excretion of Mn, Cu, and Fe, early experiences showed promising results for CaEDTA, PSH, and DFOA, respectively. Recent experiments have indicated that p-amino salicylate (PAS) plus CaEDTA may be a useful combination to remove Mn from binding sites in CNS, while the deferasirox–DFOA and the tetrathiomolybdate–DMSA combinations may be preferable to promote mobilization of Fe and Cu, respectively, from the CNS. Further research is requested to explore benefits of chelator combinations.

There is new and increasing evidence from in vitro, in vivo and clinical studies implicating the pivotal role of iron and associated metabolic pathways in the initiation, progression and development of cancer and in cancer metastasis. New metabolic and toxicity mechanisms and pathways, as well as genomic, transcription and other factors, have been linked to cancer and many are related to iron. Accordingly, a number of new targets for iron chelators have been identified and characterized in new anticancer strategies, in addition to the classical restriction of/reduction in iron supply, the inhibition of transferrin iron delivery, the inhibition of ribonucleotide reductase in DNA synthesis and high antioxidant potential. The new targets include the removal of excess iron from iron-laden macrophages, which affects anticancer activity; the modulation of ferroptosis; ferritin iron removal and the control of hyperferritinemia; the inhibition of hypoxia related to the role of hypoxia-inducible factor (HIF); modulation of the function of new molecular species such as STEAP4 metalloreductase and the metastasis suppressor N-MYC downstream-regulated gene-1 (NDRG1); modulation of the metabolic pathways of oxidative stress damage affecting mitochondrial function, etc. Many of these new, but also previously known associated iron metabolic pathways appear to affect all stages of cancer, as well as metastasis and drug resistance. Iron-chelating drugs and especially deferiprone (L1), has been shown in many recent studies to fulfill the role of multi-target anticancer drug linked to the above and also other iron targets, and has been proposed for phase II trials in cancer patients. In contrast, lipophilic chelators and their iron complexes are proposed for the induction of ferroptosis in some refractory or recurring tumors in drug resistance and metastasis where effective treatments are absent. There is a need to readdress cancer therapy and include therapeutic strategies targeting multifactorial processes, including the application of multi-targeting drugs involving iron chelators and iron–chelator complexes. New therapeutic protocols including drug combinations with L1 and other chelating drugs could increase anticancer activity, decrease drug resistance and metastasis, improve treatments, reduce toxicity and increase overall survival in cancer patients.

To compare the therapeutic effects of iron chelators used alone or in combination with phlebotomy on iron storage disease (ISD), 66 healthy common mynahs (Acridotheres tristis) were fed an iron-loading diet (3000 ppm) for 30 days. After confirmation of ISD, the birds were randomly divided into four treatment groups; DFO: deferoxamine (100 mg/kg SC q24 h), DFP: deferiprone (oral, 75 mg/kg), DFO + F: deferoxamine (100 mg/kg SC q24 h) with phlebotomy, and DFP + F: deferiprone (oral, 75 mg/kg) with phlebotomy. In phlebotomy-treated groups, blood sampling (1% BW) was performed weekly. At 1 and 2 months after treatments, seven birds from each group were euthanized and liver iron, copper, and zinc were analysed by ICP-OES assay. After 1 month, in all treatments, the liver amount of iron, copper, and zinc was reduced (P < 0.05) and there was no significant difference between groups. In the second month, the amount of liver iron, copper, and zinc decreased more in all groups, but this change was insignificant except in the DFP + F group (P < 0.05). These results suggest that all therapeutic protocols after 1 month effectively reduce the liver iron and there is no need to continue treatment. Otherwise, it may lead to iron deficiency, especially in birds treated with DFP + P. Since deferiprone, as an inexpensive oral chelator, effectively reduces liver iron levels without causing stress in the birds, it can be recommended as a more appropriate method for the treatment of mynahs with ISD. However, further clinical studies are needed to define the most effective treatment. RESEARCH HIGHLIGHTS Deferiprone is an optimized method for treating iron storage disease. The essential metals homeostasis is impaired in iron storage disease. [ABSTRACT FROM AUTHOR]

The blood–brain barrier (BBB) permeability of molecules needs to meet stringent requirements of Lipinski's rule, which pose a difficulty for the rational design of efficient chelating agents for Parkinson's disease chelation therapy. Therefore, the iron chelators employed N-aliphatic alcohols modification of deferiprone were reasonably designed in this work. The chelators not only meet Lipinski's rule for BBB permeability, but also ensure the iron affinity. The results of solution thermodynamics demonstrated that the pFe3+ value of N-hydroxyalkyl substituted deferiprone is between 19.20 and 19.36, which is comparable to that of clinical deferiprone. The results of 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays indicated that the N-hydroxyalkyl substituted deferiprone also possesses similar radical scavenging ability in comparison to deferiprone. Meanwhile, the Cell Counting Kit-8 assays of neuron-like rat pheochromocytoma cell-line demonstrated that the N-hydroxyalkyl substituted deferiprone exhibits extremely low cytotoxicity and excellent H2O2-induced oxidative stress protection effect. These results indicated that N-hydroxyalkyl substituted deferiprone has potential application prospects as chelating agents for Parkinson's disease chelation therapy strategy. [ABSTRACT FROM AUTHOR]

Superficial siderosis describes haemosiderin deposition on the surface of the brain. When present on infratentorial structures, it can cause ataxia, sensorineural hearing loss and pyramidal signs. There is no proven treatment and patients experience slow progression of symptoms. Iron-chelating agents have been suggested as a therapeutic option and deferiprone is suited as it crosses the blood-brain barrier. However, deferiprone is reported to have a 1–2% risk of agranulocytosis. We performed a systematic review on treatment of infratentorial superficial siderosis with deferiprone based on PRISMA guidelines. Studies were included if in English or an English language translation was available, were about human subjects and referred to patients with ataxia. Studies were excluded if they did not possess an English translation, included animal studies or did not have ataxia. Studies were excluded if they discussed cerebral amyloid angiopathy or siderosis of other regions. Eleven papers were included. We identified 69 patients. Seventeen patients (25%) discontinued the drug. The most encountered adverse effect was anaemia (21.7%). Neutropaenia was observed in 8.7% and agranulocytosis in 5.8% of patients. Clinically, response varied, and stability or improvement was seen across neurological domains in 6 studies while 5 showed a mixed response. On imaging, 13 (28.9%) patients improved, 24 (53.3%) stabilised and 8 (17.8%) deteriorated. A prospective international centralised register of patients should be developed to inform the design and conduct of a multicentre, placebo-controlled, randomised clinical trial to evaluate the efficacy of deferiprone. The evidence from this systematic review is that deferiprone is a promising intervention. [ABSTRACT FROM AUTHOR]

The present study evaluated the antifungal activity of the chelators deferiprone (DFP) and ethylenediaminetetraacetic acid (EDTA) and their effect on biofilm formation of the S. schenckii complex. Eighteen strains of Sporothrix spp. (seven S. brasiliensis , three S. globosa , three S. mexicana and five Sporothrix schenckii sensu stricto) were used. Minimum inhibitory concentration (MIC) values for EDTA and DFP against filamentous forms of Sporothrix spp. ranged from 32 to 128 μg/ml. For antifungal drugs, MIC values ranged from 0.25 to 4 μg/ml for amphotericin B, from 0.25 to 4 μg/ml for itraconazole, and from 0.03 to 0.25 μg/ml for terbinafine. The chelators caused inhibition of Sporothrix spp. in yeast form at concentrations ranging from 16 to 64 μg/ml (for EDTA) and 8 to 32 μg/ml (for DFP). For antifungal drugs, MIC values observed against the yeast varied from 0.03 to 0.5 μg/ml for AMB, 0.03 to 1 μg/ml for ITC, and 0.03 to 0.13 μg/ml for TRB. Both DFP and EDTA presented synergistic interaction with antifungals against Sporothrix spp. in both filamentous and yeast form. Biofilms formed in the presence of the chelators (512 μg/ml) showed a reduction of 47% in biomass and 45% in metabolic activity. Our data reveal that DFP and EDTA reduced the growth of planktonic cells of Sporothrix spp. had synergistic interaction with antifungal drugs against this pathogen, and reduced biofilm formation of Sporothrix spp. [ABSTRACT FROM AUTHOR]

Deferiprone, generally, is considered an important chelating agent for Fe3+ overload. From a literature data analysis, a lack of information on the interaction of this molecule toward a series of metal cations emerged, inducing to fill out the topic. The complexing ability of deferiprone toward Ca2+, Mg2+, Cd2+ and Pb2+ was studied by potentiometry and 1H NMR spectroscopy, in KCl aqueous solutions at different ionic strength values (0.1 ≤ I /mol dm−3 ≤ 1.0) and T = 298.15 K. The same speciation model featured by the ML, ML 2 , ML 3 and ML(OH) (M = metal and L = deferiprone or DFP) species was obtained for Cd2+ and Pb2+; the formation constants calculated at infinite dilution are: logT β = 7.23±0.02, 12.47±0.03, 16.70±0.04, and −2.53±0.04, respectively for Cd2+ and 9.91±0.01, 15.99±0.02, 19.93±0.05 and 0.99±0.02 for Pb2+. Only two species, namely ML and ML 2 , were determined for Ca2+ and Mg2+, whose formation constants at infinite dilution are respectively: 3.72±0.01 and 6.50±0.02, for the first one, 5.31±0.01 and 9.58±0.01, for the second. The ligand sequestering ability and affinity toward M2+ were evaluated by determining the pL 0.5 and pM parameters at different pHs and ionic strengths. The results suggest that deferiprone has the best complexing and sequestering ability toward Pb2+, followed by Cd2+, Mg2+ and Ca2+, respectively. 1H NMR studies confirmed the DFP affinity for Cd2+ and Pb2+, and in combination with DFT calculations showed that metal cations are bound to the hydroxo-oxo moiety of the pyridinone ring. The data reported in this study provide information on the possible employment of a small molecule like deferiprone, as a chelating and sequestering agent for Pb2+ accumulation or overload from environmental and biological matrices. [Display omitted] • Speciation study on the deferiprone interactions toward Ca2+, Mg2+, Cd2+, Pb2+. • Potential use of deferiprone ligand to remove Pb2+ contamination. • Future applications on real environmental matrixes. [ABSTRACT FROM AUTHOR]

Nosocomial infections caused by Acinetobacter baumannii (A. baumannii) are exceedingly difficult to treat, particularly in immune-compromised patients. Nanoemulsions (NEs) are a distinctive category of disinfectants that have wide range of bactericidal, fungicidal and antiviral properties by damaging their outer membranes. The inhibiting potential of iron chelators such as deferiprone (DF) used as remedial agent for different microbial groups. Combining new generation disinfectant NEs and the iron chelator DF is a logical approach to control of A. baumannii planktonic and biofilm infections. Present studies investigated the bactericidal efficacy of NE with DF by testing their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against four strains of A. baumannii. We analyzed adherence of the planktonic form both with and without deferiprone to determine possible enhancement effects. The mechanism of nanoemulsion with deferiprone (NE/DF) was quantified by LIVE/DEAD staining biofilm assay and scanning electron microscopy. DF does not affect the stability of the nanoemulsion and the combined forms show high stability. From MBC, NE/DF showed enhanced activity up to 2- to 3.3-fold compared to nanoemulsion and deferiprone alone. Combined nanoemulsion with deferiprone showed higher adherence inhibition compared to the individual forms. From confocal imaging, the level of dead cell intensity was 84.9% to 96.6% in NE/DF treated groups. Bacteria treated with NE, DF and NE/DF confirms morphological variations when compared to pili-bonded integrated control cells. We propose that biofilm destruction starts from pili removal followed by membrane destruction. These results leave a concrete evidence for the employment of nanoemulsion with deferiprone for the treatment of against drug resistant A. baumannii.

Iron is a crucial element for mammalian cells, considering its intervention in several physiologic processes. Its homeostasis is finely regulated, and its alteration could be responsible for the onset of several disorders. Iron is closely related to inflammation; indeed, during inflammation high levels of interleukin-6 cause an increased production of hepcidin which induces a degradation of ferroportin. Ferroportin degradation leads to decreased iron efflux that culminates in elevated intracellular iron concentration and consequently iron toxicity in cells and tissues. Therefore, iron chelation could be considered a novel and useful therapeutic strategy in order to counteract the inflammation in several autoimmune and inflammatory diseases. Several iron chelators are already known to have anti-inflammatory effects, among them deferiprone, deferoxamine, deferasirox, and Dp44mT are noteworthy. Recently, eltrombopag has been reported to have an important role in reducing inflammation, acting both directly by chelating iron, and indirectly by modulating iron efflux. This review offers an overview of the possible novel biological effects of the iron chelators in inflammation, suggesting them as novel anti-inflammatory molecules.

The microscale thermophoresis (MST) technique was utilized to investigate lactoferrin–drug interaction with the iron chelator, deferiprone, using label-free system. MST depends on the intrinsic fluorescence of one interacting partner. The results indicated a significant interaction between lactoferrin and deferiprone. The estimated binding constant for the lactoferrin–deferiprone interaction was 8.9 × 10−6 ± 1.6, SD, which is to be reported for the first time. Such significant binding between lactoferrin and deferiprone may indicate the potentiation of the drug secretion into a lactating mother’s milk. The technique showed a fast and simple approach to study protein–drug interaction while avoiding complicated labeling procedures. Moreover, the binding behavior of deferiprone within the binding sites of lactoferrin was investigated through molecular docking which reflected that deferiprone mediates strong hydrogen bonding with ARG121 and ASP297 in pocket 1 and forms H-bond and ionic interaction with ASN640 and ASP395, respectively, in pocket 2 of lactoferrin. Meanwhile, iron ions provide ionic interaction with deferiprone in both of the pockets. The molecular dynamic simulation further confirmed that the binding of deferiprone with lactoferrin brings conformational changes in lactoferrin that is more energetically stable. It also confirmed that deferiprone causes positive correlation motion in the interacting residues of both pockets, with strong negative correlation motion in the loop regions, and thus changes the dynamics of lactoferrin. The MM-GBSA based binding free energy calculation revealed that deferiprone exhibits ∆G TOTAL of −63,163 kcal/mol in pocket 1 and −63,073 kcal/mol in pocket 2 with complex receptor–ligand difference in pocket 1 and pocket 2 of −117.38 kcal/mol and −111.54 kcal/mol, respectively, which in turn suggests that deferiprone binds more strongly in the pocket 1. The free energy landscape of the lactoferrin–deferiprone complex also showed that this complex remains in a high energy state that confirms the strong binding of deferiprone with the lactoferrin. The current research concluded that iron-chelating drugs (deferiprone) can be transported from the mother to the infant in the milk because of the strong attachment with the lactoferrin active pockets.

NaCT mediates citrate uptake in the liver cell line HepG2. When these cells were exposed to iron (Fe3+), citrate uptake/binding as monitored by the association of [14C]-citrate with cells increased. However, there was no change in NaCT expression and function, indicating that NaCT was not responsible for this Fe3+-induced citrate uptake/binding. Interestingly however, the process exhibited substrate selectivity and saturability as if the process was mediated by a transporter. Notwithstanding these features, subsequent studies demonstrated that the iron-induced citrate uptake/binding did not involve citrate entry into cells; instead, the increase was due to the formation of citrate-Fe3+ chelate that adsorbed to the cell surface. Surprisingly, the same phenomenon was observed in culture wells without HepG2 cells, indicating the adsorption of the citrate-Fe3+ chelate to the plastic surface of culture wells. We used this interesting phenomenon as a simple screening technique for new iron chelators with the logic that if another iron chelator is present in the assay system, it would compete with citrate for binding to Fe3+ and prevent the formation and adsorption of citrate-Fe3+ to the culture well. This technique was validated with the known iron chelators deferiprone and deferoxamine, and with the bacterial siderophore 2,3-dihydroxybenzoic acid and the catechol carbidopa.

The need for preparing new strategies for the design of emergency drug therapies against COVID-19 and similar diseases in the future is rather urgent, considering the high rate of morbidity and especially mortality associated with COVID-19, which so far has exceeded 18 million lives. Such strategies could be conceived by targeting the causes and also the serious toxic side effects of the diseases, as well as associated biochemical and physiological pathways. Deferiprone (L1) is an EMA- and FDA-approved drug used worldwide for the treatment of iron overload and also other conditions where there are no effective treatments. The multi-potent effects and high safety record of L1 in iron loaded and non-iron loaded categories of patients suggests that L1 could be developed as a “magic bullet” drug against COVID-19 and diseases of similar symptomatology. The mode of action of L1 includes antiviral, antimicrobial, antioxidant, anti-hypoxic and anti-ferroptotic effects, iron buffering interactions with transferrin, iron mobilizing effects from ferritin, macrophages and other cells involved in the immune response and hyperinflammation, as well as many other therapeutic interventions. Similarly, several pharmacological and other characteristics of L1, including extensive tissue distribution and low cost of production, increase the prospect of worldwide availability, as well as many other therapeutic approach strategies involving drug combinations, adjuvant therapies and disease prevention.

Objectives: To assess the efficacy and safety of dual oral iron chelation therapy (deferiprone and deferasirox) in decreasing iron overload status, using serum ferritin and liver and cardiac MRI as indicators, in transfusion dependent thalassemic children. Methods: This was a prospective observational study conducted in a tertiary care hospital for a period of one year. Children with thalassemia between 2 and 18 y of age with serum ferritin above 1500 ng/ml were started on oral deferiprone and deferasirox. They were followed up for one year. Serum ferritin and MRI quantification of liver and cardiac iron concentration was done at enrolment and end of 12 mo. They were also monitored monthly for any adverse effects. Results: Twenty one thalassemic children with mean age of 7.8 y (range 4–12 y) and a mean ferritin value of 3129 + 1231.5 ng/ml were enrolled. Mean serum ferritin decreased by 1226.3 ng/ml (p = 0.047, 95% CI =10.2, 1504.3) with 16.8% fall from baseline. The reduction in ferritin correlated significantly with the initial ferritin level (spearman's rho = 0.742, p = 0.001). Mean liver iron concentration and myocardial iron concentration did not change significantly. Red color urine, transient rise in creatinine and liver enzymes were noted during the study period. Conclusions: Combined oral chelation with deferiprone and deferasirox significantly decreases the serum ferritin level in children with severe iron overload. The drugs were tolerated well without any serious adverse effects. [ABSTRACT FROM AUTHOR]

The accumulation of neurofibrillary tangles (NFTs), which is composed of abnormally hyperphosphorylated tau aggregates, is the classic neuropathology associated with cognitive dysfunction in tauopathies such as Alzheimer's disease (AD). However, there is an emerging theory suggesting that dysregulation in cerebral iron may contribute to NFT formation. Iron is speculated to bind to tau and induce conformational changes of the protein, potentially leading to subsequent aggregation and cognitive decline. Deferiprone (DFP) is a clinically available iron chelator, which has demonstrated potential therapeutic advantages of chelating iron in neurodegenerative disorders, and is currently in clinical trials for AD. However, its effect on tau pathology remains unclear. Here, we report the effects of short-term DFP treatment (4 weeks, 100 mg/kg/daily, via oral gavage) in a mixed-gender cohort of the rTg(tauP301L)4510 mouse model of tauopathy. Our results revealed that DFP improved Y-maze and open field performance, accompanied by a 28% decrease in brain iron levels, measured by inductively coupled plasma mass spectrometry (ICP-MS) and reduced AT8-labeled p-tau within the hippocampus in transgenic tau mice. This data supports the notion that iron may play a neurotoxic role in tauopathies and may be a potential therapeutic target for this class of disorders that can be modulated by the clinically available metal chelator DFP. [ABSTRACT FROM AUTHOR]

In this study, we compare the effects of deferiprone (Def) and tetraethylammonium salt of salinomycinic acid (Sal) on lead (Pb)-induced toxicity in testes of Pb-exposed mice. Mature male ICR mice were allocated into four groups as follows: untreated control mice (ctrl)—received distilled water for 4 weeks; Pb-exposed mice (Pb)—subjected to 14-day Pb (II) nitrate administration at dose 80 mg/kg body weight (b.w.); Pb + Def group—Pb-exposed mice, treated with 20 mg/kg b.w. Def for 2 weeks; and Pb + Sal group—Pb-intoxicated mice, treated with 16 mg/kg b.w. Sal for 14 days. The results demonstrated that Pb exposure significantly increased blood and testicular Pb concentrations, decreased testicular calcium (Ca) content, significantly elevated testicular levels of magnesium (Mg), zinc (Zn), and selenium (Se) but did not significantly affect the endogenous contents of phosphorous (P) and iron (Fe) compared with untreated controls. Pb intoxication induced disorganization of the seminiferous epithelium. Def or Sal administration reduced blood Pb and testicular Pb concentrations in Pb-exposed mice compared with the Pb-intoxicated group. Mg, Zn, and Se concentrations in testes of Pb-exposed mice, treated with Def or Sal, remained higher compared with the untreated controls. Sal significantly increased testicular P concentration compared with untreated controls and significantly elevated the testicular Ca and Fe concentrations compared with the toxic control group. Both chelating agents improved testicular morphology to a great extent. The results demonstrate the potential of both compounds as antidotes for treatment of Pb-induced impairment of male reproductive function. [ABSTRACT FROM AUTHOR]

Background: Thalassemia is a chronic disease requiring lifelong treatment. The adherence to regular iron chelation therapy is important to ensure complication-free survival and good quality of life. The study aim to assess the adherence to iron chelation therapy (ICT) in patients with transfusion-dependent thalassemia (TDT), evaluate various causes of non-adherence and study the impact of non-adherence on the prevalence of complications secondary to iron overload. Materials and Methods: Patients with TDT on ICT for > 6 months were enrolled in the study. Hospital records were reviewed for demographic details, iron overload status, treatment details, and the prevalence of complications. A study questionnaire was used to collect information on adherence to ICT, knowledge of patients, and the possible reasons for non-adherence. Results: A total of 215 patients with a mean age of 15.07+7.68 years and an M: F ratio of 2.2:1 were included in the study. Non-adherence to ICT was found in 10.7% of patients. Serum ferritin levels were significantly higher in the non-adherent group (3129.8+1573.2 µg/l) than the adherent population (2013.1+1277.1 µg/l). Cardiac as well as severe liver iron overload was higher in the non-adherent patients. No correlation was found between disease knowledge and adherence to ICT. Difficulties in drug administration and many medicines to be taken daily were statistically significant reasons for non-adherence. There was no difference in the co-morbidities arising due to the iron overload in the two groups. Conclusion: Nearly 11% of patients with TDT were non-adherent to ICT. Non-adherence results in higher iron overload.