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Neurotherapeutics : the Journal of the... Oct 2023
PubMed: 37817049
DOI: 10.1007/s13311-023-01448-3 -
Pediatric Blood & Cancer Jan 2024Children with sickle cell disease (SCD) who are chronically transfused often, require iron chelation therapy. There are limited data that allow for comparison of the...
Deferiprone versus deferoxamine for transfusional iron overload in sickle cell disease and other anemias: Pediatric subgroup analysis of the randomized, open-label FIRST study.
BACKGROUND
Children with sickle cell disease (SCD) who are chronically transfused often, require iron chelation therapy. There are limited data that allow for comparison of the efficacy and safety of the iron chelator deferiprone versus deferoxamine in children with SCD.
METHODS
This post hoc analysis of the phase 3b/4, randomized, open-label FIRST (Ferriprox in Patients with IRon Overload in Sickle Cell Disease Trial) study (NCT02041299) included patients 17 years and younger with SCD or other anemias receiving deferiprone or deferoxamine.
RESULTS
Overall, 142 patients were evaluated; mean ages were 10.5 and 11.7 years in the deferiprone and deferoxamine groups, respectively. At 12 months: mean change from baseline in liver iron concentration was -3.3 mg/g dry weight (dw) with deferiprone and -3.4 mg/g dw with deferoxamine (p = .8216); relative mean change (coefficient of variation %) in log cardiac T2* magnetic resonance imaging was 1.02 (21.8%) with deferiprone and 0.95 (19.5%) with deferoxamine (p = .0717); and the mean (standard error) change in serum ferritin levels was -133.0 (200.3) μg/L with deferiprone and -467.1 (244.1) μg/L with deferoxamine (p = .2924). The most common deferiprone-related adverse events (AEs) were upper abdominal pain (20.2%), vomiting (13.8%), pyrexia (9.6%), decreased neutrophil count (9.6%), increased alanine aminotransferase (ALT; 9.6%), and increased aspartate aminotransferase (AST; 9.6%). All cases of increased ALT, increased AST, and neutropenia resolved, most without intervention.
CONCLUSIONS
This post hoc analysis of pediatric patients from FIRST corroborated previous findings in adults that deferiprone is comparable to deferoxamine in reducing iron overload. No new safety concerns were observed. Deferiprone is an oral chelation option that could improve adherence and outcomes in children.
Topics: Adult; Child; Humans; Anemia, Sickle Cell; beta-Thalassemia; Deferiprone; Deferoxamine; Iron; Iron Chelating Agents; Iron Overload; Neutropenia; Pyridones
PubMed: 37807937
DOI: 10.1002/pbc.30711 -
Letters in Applied Microbiology Oct 2023This study evaluated the antibiofilm activity of promethazine, deferiprone, and Manuka honey against Staphylococcus aureus and Pseudomonas aeruginosa in vitro and ex...
This study evaluated the antibiofilm activity of promethazine, deferiprone, and Manuka honey against Staphylococcus aureus and Pseudomonas aeruginosa in vitro and ex vivo in a wound model on porcine skin. The minimum inhibitory concentrations (MICs) and the effects of the compounds on biofilms were evaluated. Then, counting colony-forming units (CFUs) and confocal microscopy were performed on biofilms cultivated on porcine skin for evaluation of the compounds. For promethazine, MICs ranging from 97.66 to 781.25 µg/ml and minimum biofilm eradication concentration (MBEC) values ranging from 195.31 to 1562.5 µg/ml were found. In addition to reducing the biomass of both species' biofilms. As for deferiprone, the MICs were 512 and >1024 µg/ml, the MBECs were ≥1024 µg/ml, and it reduced the biomass of biofilms. Manuka honey had MICs of 10%-40%, MBECs of 20 to >40% and reduced the biomass of S. aureus biofilms only. Concerning the analyses in the ex vivo model, the compounds reduced (P < .05) CFU counts for both bacterial species, altering the biofilm architecture. The action of the compounds on biofilms in in vitro and ex vivo tests raises the possibility of using them against biofilm-associated wounds. However, further studies are needed to characterize the mechanisms of action and their effectiveness on biofilms in vivo.
Topics: Animals; Swine; Staphylococcus aureus; Promethazine; Deferiprone; Honey; Biofilms; Pseudomonas aeruginosa; Anti-Bacterial Agents; Microbial Sensitivity Tests
PubMed: 37791895
DOI: 10.1093/lambio/ovad119 -
International Wound Journal Feb 2024There is an increasing use of non-medicated wound dressing with claims of irreversible bacterial binding. Most of the data are from in vitro models which lack clinical...
There is an increasing use of non-medicated wound dressing with claims of irreversible bacterial binding. Most of the data are from in vitro models which lack clinical relevance. This study employed a range of in vitro experiments to address this gap and we complemented our experimental designs with in vivo observations using dressings obtained from patients with diabetes-related foot ulcers. A hydrophobic wound dressing was compared with a control silicone dressing in vitro. Test dressings were placed on top of a Pseudomonas aeruginosa challenge suspension with increasing concentrations of suspension inoculum in addition to supplementation with phosphate buffered saline (PBS) or increased protein content (IPC). Next, we used the challenge suspensions obtained at the end of the first experiment, where bacterial loads from the suspensions were enumerated following test dressing exposure. Further, the time-dependent bacterial attachment was investigated over 1 and 24 h. Lastly, test dressings were exposed to a challenge suspension with IPC, with or without the addition of the bacteriostatic agent Deferiprone to assess the impacts of limiting bacterial growth in the experimental design. Lastly, two different wound dressings with claims of bacterial binding were obtained from patients with chronic diabetes-related foot ulcers after 72 h of application and observed using scanning electron microscope (SEM). Bacteria were enumerated from each dressing after a 1-h exposure time. There was no statistical difference in bacterial attachment between both test dressings when using different suspension inoculum concentrations or test mediums. Bacterial attachment to the two test dressings was significantly lower (p < 0.0001) when IPC was used instead of PBS. In the challenge suspension with PBS, only the hydrophobic dressing achieved a statistically significant reduction in bacterial loads (0.5 ± 0.05 log colony forming units; p = 0.001). In the presence of IPC, there was no significant reduction in bacterial loads for either test dressing. When bacterial growth was arrested, attachment to the test dressings did not increase over time, suggesting that the number of bacteria on the test dressings increases over time due to bacterial growth. SEM identified widespread adsorption of host fouling across the test dressings which occurred prior to microbial binding. Therein, microbial attachment occurred predominantly to host fouling and not directly to the dressings. Bacterial binding is not unique to dialkylcarbamoyl chloride (DACC) dressings and under clinically relevant in vitro conditions and in vivo observations, we demonstrate (in addition to previously published work) that the bacterial binding capabilities are not effective at reducing the number of bacteria in laboratory models or human wounds.
Topics: Humans; Diabetic Foot; Anti-Infective Agents; Bandages; Foot Ulcer; Bacteria
PubMed: 37770025
DOI: 10.1111/iwj.14416 -
BioMed Research International 2023The primary aim of this study was to evaluate the prevalence of iron overload and the real-world clinical effectiveness of the iron chelation therapies (ICTs) in Syrian... (Observational Study)
Observational Study
OBJECTIVES
The primary aim of this study was to evaluate the prevalence of iron overload and the real-world clinical effectiveness of the iron chelation therapies (ICTs) in Syrian patients with transfusion-dependent beta thalassemia major (BTM) prior to and during the ongoing Syrian conflict.
METHODS
This single-center, two-stage observational study was conducted at Homs National Thalassemia Center (HNTC) prior to (2009) and during (2019) the armed conflict. The prevalence and the severity of iron overload, as well as the effectiveness of four iron chelation regimens, were assessed using serum ferritin (SF) concentrations as a means of monitoring in two cohorts of BTM patients receiving deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX), or a combination of DFO and DFP therapy in both years. Statistical analyses encompassed one-way ANOVA, Kruskal-Wallis, Mann-Whitney , and chi-square (2) tests for the comparisons of the variables and the frequencies between the two cohorts and subgroups.
RESULTS
We included all eligible BTM patients at HNTC in 2009 ( = 205) and 2019 ( = 172). Only 84 patients from the 2009 cohort were accessible in 2019. Our findings revealed that 98% and 89% of the patients had iron overload ( ≥ 1500 ng/mL) and comparable elevated median SF concentrations (3868 and 3757 ng/mL) in 2009 and 2019, respectively ( = 0.275). Furthermore, patients on DFO demonstrated the poorest control of iron overload and the highest SF concentrations (4319 and 5586 ng/mL), whereas those on DFX achieved superior outcomes and the lowest SF concentrations (3355 and 2152 ng/mL) in both years. Twenty-six patients from the 2019 cohort received no ICT for six years (from 2012 to 2018) and experienced extremely severe iron overload with SF levels ranging between 4481 and 16,000 ng/mL.
CONCLUSIONS
Our findings prove a high prevalence of iron overload and suboptimal chelation outcomes in Syrian BTM patients, both prior to and during the ongoing armed conflict, despite the provision of free ICTs at HNTC. Poor adherence and older age of patients may explain the unfavorable outcomes of DFO and (DFO+DFP) regimens, whereas younger age and higher socioeconomic status may have contributed to the lowest SF and superior outcomes in patients on DFX. This study also demonstrates the crucial role of the National Thalassemia Centers, namely HNTC, in providing health services to BTM patients in times of peace and conflict.
Topics: Humans; Animals; Cricetinae; beta-Thalassemia; Prevalence; Syria; Analysis of Variance; Iron Overload; Mesocricetus
PubMed: 37743972
DOI: 10.1155/2023/8911518 -
Redox Biology Nov 2023Toxoplasmosis is a major infectious disease, affecting approximately one-third of the world's population; its main clinical manifestation, ocular toxoplasmosis (OT), is...
Toxoplasmosis is a major infectious disease, affecting approximately one-third of the world's population; its main clinical manifestation, ocular toxoplasmosis (OT), is a severe sight-threatening disease. Nevertheless, the diagnosis of OT is based on clinical findings, which needs improvement, even with biochemical tests, such as polymerase chain reaction and antibody detections. Furthermore, the efficacy of OT-targeted treatment is limited; thus, additional measures for diagnosis and treatments are needed. Here, we for the first time report a significantly reduced iron concentration in the vitreous humor (VH) of human patients infected with OT. To obtain further insights into molecular mechanisms, we established a mouse model of T. gondii infection, in which intravitreally injected tracer Fe, was accumulated in the neurosensory retina. T. gondii-infected eyes showed increased lipid peroxidation, reduction of glutathione peroxidase-4 expression and mitochondrial deformity in the photoreceptor as cristae loss. These findings strongly suggest the involvement of ferroptotic process in the photoreceptor of OT. In addition, deferiprone, an FDA-approved iron chelator, reduced the iron uptake but also ameliorated toxoplasma-induced retinochoroiditis by reducing retinal inflammation. In conclusion, the iron levels in the VH could serve as diagnostic markers and iron chelators as potential treatments for OT.
Topics: Animals; Mice; Humans; Toxoplasmosis, Ocular; Ferroptosis; Toxoplasma; Chorioretinitis; Retina; Iron
PubMed: 37738924
DOI: 10.1016/j.redox.2023.102890 -
Neural Regeneration Research Mar 2024The positive effect of levodopa in the treatment of Parkinson's disease, although it is limited in time and has severe side effects, has encouraged the scientific... (Review)
Review
The positive effect of levodopa in the treatment of Parkinson's disease, although it is limited in time and has severe side effects, has encouraged the scientific community to look for new drugs that can stop the neurodegenerative process or even regenerate the neuromelanin-containing dopaminergic nigrostriatal neurons. Successful preclinical studies with coenzyme Q10, mitoquinone, isradipine, nilotinib, TCH346, neurturin, zonisamide, deferiprone, prasinezumab, and cinpanemab prompted clinical trials. However, these failed and after more than 50 years levodopa continues to be the key drug in the treatment of the disease, despite its severe side effects after 4-6 years of chronic treatment. The lack of translated successful results obtained in preclinical investigations based on the use of neurotoxins that do not exist in the human body as new drugs for Parkinson's disease treatment is a big problem. In our opinion, the cause of these failures lies in the experimental animal models involving neurotoxins that do not exist in the human body, such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 6-hydroxydopamine, that induce a very fast, massive and expansive neurodegenerative process, which contrasts with the extremely slow one of neuromelanin-containing dopaminergic neurons. The exceedingly slow progress of the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson's patients is due to (i) a degenerative model in which the neurotoxic effect of an endogenous neurotoxin affects a single neuron, (ii) a neurotoxic event that is not expansive and (iii) the fact that the neurotoxin that triggers the neurodegenerative process is produced inside the neuromelanin-containing dopaminergic neurons. The endogenous neurotoxin that fits this degenerative model involving one single neuron at a time is aminochrome, since it (i) is generated within neuromelanin-containing dopaminergic neurons, (ii) does not cause an expansive neurotoxic effect and (iii) triggers all the mechanisms involved in the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson's disease. In conclusion, based on the hypothesis that the neurodegenerative process of idiopathic Parkinson's disease corresponds to a single-neuron neurodegeneration model, we must search for molecules that increase the expression of the neuroprotective enzymes DT-diaphorase and glutathione transferase M2-2. It has been observed that the activation of the Kelch-like ECH-associated protein 1/nuclear factor (erythroid-derived 2)-like 2 pathway is associated with the transcriptional activation of the DT-diaphorase and glutathione transferase genes.
PubMed: 37721280
DOI: 10.4103/1673-5374.380878 -
Neurotoxicology Dec 2023Methamphetamine (METH) has been established to selectively target and impair dopaminergic neurons through multiple pathways. Ferroptosis is a unique form of...
Methamphetamine (METH) has been established to selectively target and impair dopaminergic neurons through multiple pathways. Ferroptosis is a unique form of non-apoptotic cell death driven by cellular iron accumulation-induced lipid peroxidation. Nonetheless, it remains unclear whether METH can induce ferroptosis. In the present study, we sought to assess alterations in iron levels after chronic METH exposure and reveal the modulatory role of iron on METH-induced pathologies. Importantly, we demonstrated that METH increased iron deposition in the nigrostriatal system, including the substantia nigra (SN) and caudate putamen (CPu). Moreover, decreases in GPx4 levels, increases in lipid peroxidation products, and pathological alterations were observed in the nigrostriatal system as a consequence of chronic METH exposure. The iron chelator deferiprone not only alleviated nigrostriatal iron deposition, dopaminergic cell death, and lipid peroxidation, but alsoattenuated the decreases in GPx4 induced by METH. These findings suggest an alleviation of ferroptosis in dopaminergic neurons. In addition, we found that the ferroptosis inhibitor liproxstatin-1 attenuated METH-induced dopaminergic degeneration in the nigrostriatal system. Our findings corroborated that METH might induce dopaminergic neurodegeneration through iron-dependent ferroptosis. Interestingly, reducing iron levels or inhibiting ferroptosis may alleviate METH-induced dopaminergic neurodegeneration.
Topics: Mice; Animals; Methamphetamine; Dopamine; Brain; Iron; Iron Chelating Agents
PubMed: 37717738
DOI: 10.1016/j.neuro.2023.09.006 -
The Journal of International Medical... Sep 2023Superficial siderosis of the central nervous system (SSCNS) is a rare disease characterized by iron deposition on the tissue surface of the middle axis system. We report... (Review)
Review
Superficial siderosis of the central nervous system (SSCNS) is a rare disease characterized by iron deposition on the tissue surface of the middle axis system. We report the case of a man in his late 40 s who was admitted to the hospital with ataxia. A physical examination revealed cerebellar ataxia, sensorineural deafness, and bilateral pyramidal tract injury. Susceptibility-weighted magnetic resonance imaging showed linear hypointense signals on the surface of the cerebral hemispheres, sulcus gyrus, lateral ventricles, and cerebellum. The patient underwent treatment with deferiprone, mecobalamin, and vitamin B1, and the symptoms were not aggravated. The patient's daily living ability was near normal after 1 year of follow-up. A literature review indicated that most SSCNS patients present diverse clinical manifestations. Clinicians may consider SSCNS in patients with hearing impairment and gait ataxia, especially for those receiving anticoagulant therapy and with a history of brain injury or accident.
Topics: Male; Humans; Siderosis; Central Nervous System; Brain Injuries; Hearing Loss, Sensorineural; Cell Membrane
PubMed: 37702555
DOI: 10.1177/03000605231198389 -
American Journal of Physiology. Heart... Nov 2023Children with beta-thalassemia (BT) present with an increase in carotid intima-medial thickness, an early sign suggestive of premature atherosclerosis. However, it is...
Children with beta-thalassemia (BT) present with an increase in carotid intima-medial thickness, an early sign suggestive of premature atherosclerosis. However, it is unknown if there is a direct relationship between BT and atherosclerotic disease. To evaluate this, wild-type (WT, littermates) and BT (Hbb) mice, both male and female, were placed on a 3-mo high-fat diet with low-density lipoprotein receptor suppression via overexpression of proprotein convertase subtilisin/kexin type 9 (PCSK9) gain-of-function mutation (D377Y). Mechanistically, we hypothesize that heme-mediated oxidative stress creates a proatherogenic environment in BT because BT is a hemolytic anemia that has increased free heme and exhausted hemopexin, heme's endogenous scavenger, in the vasculature. We evaluated the effect of hemopexin (HPX) therapy, mediated via an adeno-associated virus, to the progression of atherosclerosis in BT and a phenylhydrazine-induced model of intravascular hemolysis. In addition, we evaluated the effect of deferiprone (DFP)-mediated iron chelation in the progression of atherosclerosis in BT mice. Aortic en face and aortic root lesion area analysis revealed elevated plaque accumulation in both male and female BT mice compared with WT mice. Hemopexin therapy was able to decrease plaque accumulation in both BT mice and mice on our phenylhydrazine (PHZ)-induced model of hemolysis. DFP decreased atherosclerosis in BT mice but did not provide an additive benefit to HPX therapy. Our data demonstrate for the first time that the underlying pathophysiology of BT leads to accelerated atherosclerosis and shows that heme contributes to atherosclerotic plaque development in BT. This work definitively shows for the first time that beta-thalassemia leads to accelerated atherosclerosis. We demonstrated that intravascular hemolysis is a prominent feature in beta-thalassemia and the resulting increases in free heme are mechanistically relevant. Adeno-associated virus (AAV)-hemopexin therapy led to decreased free heme and atherosclerotic plaque area in both beta-thalassemia and phenylhydrazine-treated mice. Deferiprone-mediated iron chelation led to deceased plaque accumulation in beta-thalassemia mice but provided no additive benefit to hemopexin therapy.
Topics: Humans; Child; Male; Female; Mice; Animals; Plaque, Atherosclerotic; Proprotein Convertase 9; beta-Thalassemia; Hemopexin; Deferiprone; Hemolysis; Aortic Diseases; Mice, Knockout; Atherosclerosis; Heme; Phenylhydrazines; Iron Chelating Agents; Mice, Inbred C57BL
PubMed: 37682237
DOI: 10.1152/ajpheart.00306.2023