Trial of Deferiprone in Parkinson's Disease

BACKGROUND

Iron content is increased in the substantia nigra of persons with Parkinson's disease and may contribute to the pathophysiology of the disorder. Early research suggests that the iron chelator deferiprone can reduce nigrostriatal iron content in persons with Parkinson's disease, but its effects on disease progression are unclear.

METHODS

We conducted a multicenter, phase 2, randomized, double-blind trial involving participants with newly diagnosed Parkinson's disease who had never received levodopa. Participants were assigned (in a 1:1 ratio) to receive oral deferiprone at a dose of 15 mg per kilogram of body weight twice daily or matched placebo for 36 weeks. Dopaminergic therapy was withheld unless deemed necessary for symptom control. The primary outcome was the change in the total score on the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 260, with higher scores indicating more severe impairment) at 36 weeks. Secondary and exploratory clinical outcomes at up to 40 weeks included measures of motor and nonmotor disability. Brain iron content measured with the use of magnetic resonance imaging was also an exploratory outcome.

RESULTS

A total of 372 participants were enrolled; 186 were assigned to receive deferiprone and 186 to receive placebo. Progression of symptoms led to the initiation of dopaminergic therapy in 22.0% of the participants in the deferiprone group and 2.7% of those in the placebo group. The mean MDS-UPDRS total score at baseline was 34.3 in the deferiprone group and 33.2 in the placebo group and increased (worsened) by 15.6 points and 6.3 points, respectively (difference, 9.3 points; 95% confidence interval, 6.3 to 12.2; P<0.001). Nigrostriatal iron content decreased more in the deferiprone group than in the placebo group. The main serious adverse events with deferiprone were agranulocytosis in 2 participants and neutropenia in 3 participants.

CONCLUSIONS

In participants with early Parkinson's disease who had never received levodopa and in whom treatment with dopaminergic medications was not planned, deferiprone was associated with worse scores in measures of parkinsonism than those with placebo over a period of 36 weeks. (Funded by the European Union Horizon 2020 program; FAIRPARK-II ClinicalTrials.gov number, NCT02655315.).

Effects of dietary chromium picolinate supplementation on broiler growth performance: A meta-analysis

Objective

A meta-analysis was conducted to assess the effects of dietary chromium picolinate (CrPic) supplementation on broiler growth performance and to determine whether such effects are regulated by broiler strains, sex, environmental stress, or contextual factors including study area and years.

Methods

Eligible studies were identified by searching the Web of Science, Springer, Elsevier, ScienceDirect, Taylor & Francis Online databases. Weighted average differences with corresponding 95% confidence intervals were computed with a random-effects model. We performed subgroup analysis stratified by study area, published years, broiler strains and sex, and environmental stress. Publication bias was assessed with Egger’s test method. A total of 15 studies eligible for inclusion.

Results

The results indicated that CrPic supplementation significantly improved broiler growth performance and subgroup analysis confirmed this conclusion. We also found that Ross 308 or male broilers might be more sensitive to CrPic supplementation and showed better growth performance. A model was used to obtain the amount of chromium addition under the optimal growth performance, which suggested that the maximum value of average daily gain (ADG) was reached when chromium addition was 1810 μg/kg. The results of the sensitivity analysis showed low sensitivity and high stability of the meta-analysis.

Conclusions

CrPic supplementation had a positive effect on the growth performance of broilers, and this meta-analysis provides a more accurate value of chromium addition, which may be beneficial for the practice of the broiler industry.

Efficacy And Tolerability Of Oral Iron Chelator, Deferasirox

BACKGROUND

Thalassemia major is the severe form of β thalassemia characterized by severe anaemia, hepatosplenomegaly and facioskeletal changes due to increased haemolysis of defective red blood cells. In iron overload states, high levels of iron exceed the iron-carrying capacity of transferrin within the plasma, leading to the formation of nontransferrin-bound iron form. These nontransferrin-bound iron forms can be taken up into cells, including liver, heart, and endocrine cells leading to organ damage. To prevent complications associated with hemosiderosis, iron chelation therapy remains one of the main objectives of clinical management of the patients affected by Thalassemia Major.

METHODS

Thirty-seven patients were enrolled using non randomized convenience sampling technique after the written consent from patients. Patients age 2-30 years were enrolled in this study. Serum Ferritin, ALT, Serum Creatinine were checked at the start of the study, 3 months, 6months and then at the end of the study, i.e., at 9 months of the commencement of the study. They were also assessed for other side effects pertaining to oral tolerability of the drug like vomiting, nausea, GI upset, diarrhoea, urinary complaints or any other subjective complaint.

RESULTS

Of the 37 patients, 20 were male (54.1%) and 17 were female (45.9%). Mean age of the patients was 10.2 years (Min. 3 years, Max 21 years). The average serum Ferritin at baseline was noted as 3440 which increased after a period of 3 months, 6 months and 9 months with average of 3359, 3677 and 4394 respectively. After the period of 9 months largest 95% confidence interval of serum Ferritin levels was observed in the range of 3420.17 to 5368.63. In our study, 17 patients required alternative chelation (46%). These patients needed IV Deferioxamine because of the rising trend of Serum Ferritin after the study.

CONCLUSIONS

From the results of our study, we infer that oral Deferasirox is not an effective iron chelator. If the patients are taking oral deferasirox, their Serum Ferritin should be checked 3 monthlies. The drug is effective only in maintaining Serum Ferritin levels with levels less than 1500ng/ml. Intravenous Deferioxamine still should be preferred over oral iron chelators for effective control of iron overload and its complications.

Iron Chelation in Local Infection

Iron is an essential element in multiple biochemical pathways in humans and pathogens. As part of the innate immune response in local infection, iron availability is restricted locally in order to reduce overproduction of reactive oxygen species by the host and to attenuate bacterial growth. This physiological regulation represents the rationale for the therapeutic use of iron chelators to support induced iron deprivation and to treat infections. In this review paper we discuss the importance of iron regulation through examples of local infection and the potential of iron chelation in treating infection.

Management of Iron Overload in Beta-Thalassemia Patients: Clinical Practice Update Based on Case Series

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.

Approaches to Disease Modification for Parkinson's Disease: Clinical Trials and Lessons Learned

Despite many clinical trials over the last three decades, the goal of demonstrating that a treatment slows the progression of Parkinson's disease (PD) remains elusive. Research advances have shed new insight into cellular pathways contributing to PD pathogenesis and offer increasingly compelling therapeutic targets. Here we review recent and ongoing clinical trials employing novel strategies toward disease modification, including those targeting alpha-synuclein and those repurposing drugs approved for other indications. Active and passive immunotherapy approaches are being studied with the goal to modify the spread of alpha-synuclein pathology in the brain. Classes of currently available drugs that have been proposed to have potential disease-modifying effects for PD include calcium channel blockers, antioxidants, anti-inflammatory agents, iron-chelating agents, glucagon-like peptide 1 agonists, and cAbl tyrosine kinase inhibitors. The mechanistic diversity of these treatments offers hope, but to date, results from these trials have been disappointing. Nevertheless, they provide useful lessons in guiding future therapeutic development.

Cost-utility of new film-coated tablet formulation of deferasirox vs deferoxamine among major beta-thalassemia patients in Iran

OBJECTIVES

Thalassemia is a hereditary disease, which caused economic burden in developing countries. This study evaluated the cost utility of new formulation of deferasirox (Jadenu) vs deferoxamine (Desferal) among B-Thalassemia-major patients from payer perspective in Iran.

METHODS

An economic-evaluation through Markov model was performed. A systematic review was conducted in order to evaluate the clinical effectiveness of comparators. Because of chelating therapy is weight-dependent, patients were assumed to be 2 years-old at initiation in first and 18 years-old in second scenario, and model was estimated lifetime costs and utilities. Costs were calculated to the Iran healthcare system through payer perspective and measured effectiveness using quality-adjusted life years (QALYs). One-way sensitivity analysis and budget impact analysis was also employed.

RESULTS

The 381 studies were retrieved from systematic searching through databases. After eliminating duplicate and irrelevant studies, 2 studies selected for evaluating the effectiveness. Jadenu was associated with an incremental cost-effectiveness ratio (ICER) of 1470.6 and 2544.7 US$ vs Desferal in first and second scenario respectively. The estimated ICER for Jadenu compared to generic deferoxamine was 2837.0 and 6924.1 US$ for first and second scenario respectively. For all scenarios Jadenu is presumed as cost-effective option based on calculated ICER which was lower than 1 gross domestic product per capita in Iran. Sensitivity analysis showed that different parameters except discount rate and indirect cost did not have impact on results. Based on budget impact analysis the estimated cost for patients using Desferal (based on the market share of brand) was 44,021,478 US$ in 3 years vs 42,452,606 US$ in replacing 33% of brand market share with Jadenu. This replacement corresponded to the cost saving of almost 1,568,872 US$ for the payers in 3 years. The calculated cost of using generic deferoxamine in all patients was 68,948,392 US$. The increase in the cost of using Jadenu for 10% of all patients in this scenario would be 934,427 US$ (1.36%) US$ at the first year.

CONCLUSIONS

Based on this analysis, film-coated deferasirox appeared to be cost-effective treatment in comparison with Desferal for managing child and adult chronic iron overload in B-thalassemia major patients of Iran.

Comparison of Oral and Parenteral Iron Administration on Iron Homeostasis, Oxidative and Immune Status in Anemic Neonatal Pigs

The present study was to evaluate the consequences of iron status across oral and parenteral iron administrations in prevention of iron deficiency anemia. A total of 24 one-day-old male neonatal piglets were allocated into three groups given non-iron supplementation (NON), intramuscular iron dextran injection (FeDex), and oral administration of ferrous glycine chelate (FeGly), respectively. At day 8, no significant differences in final body weight, average weight gain, and tissue coefficients were observed among three groups (P > 0.05). Both oral FeGly and FeDex injection significantly increased serum iron, ferritin, hemoglobin, and tissue iron deposition (P < 0.05). However, FeDex-injected supplementation resulted in rapidly rising hepcidin levels and hepatic iron deposition (P < 0.05). In addition, compared to parenteral iron supplementation, greater serum IgA level, SOD, and GSH-Px activities, lower expressions of IL-1β and TNF-α in the liver, and lower expressions of IL-6 and TNF-α in the spleen were found in oral iron piglets (P < 0.05). According to our results, oral administration of ferrous glycine chelate improved iron homeostasis, and oxidative and immune status in anemic neonatal pigs.

Fibroblast Growth Factor 23 (FGF23) and Klotho Protein in Beta-Thalassemia

Derangements in phosphate and calcium homeostasis are common in patients with beta-thalassemia. Fibroblast growth factor 23 (FGF23) is among the main hormones regulating phosphate levels, while several studies underline an interplay between iron (Fe) and FGF23. Herein, we investigated, for the first time, the serum intact molecule (iFGF23) and the carboxyl-terminal fragment (C-FGF23) and Klotho levels simultaneously in patients with beta-thalassemia major receiving iron chelation regimens in comparison to healthy control subjects. We also correlated them with the body iron burden. The observational case-control study included 81 subjects (40 thalassemic patients and 41 healthy controls). Serum iFGF23, C-FGF23 and Κlotho were measured by ELISA. Parathormone, 25-hydroxycholecalciferol, calcium, and phosphorus were measured in blood and/or urine. The degree of hemosiderosis was evaluated by assessing the serum ferritin levels and performing T2* MRI measurements. Serum C-FGF23 levels were significantly lower in patients compared to control subjects (p=0.04), while iFGF23 and Klotho levels did not differ. Serum C-FGF23 levels were negatively correlated with ferritin (r=-0,421, p=0.018), whereas there were no significant correlations of each of the three factors with the iron chelation therapy. Decreased serum C-FGF23 levels were found in βTh patients which may be attributed to inhibition of proteolytic cleavage of iFGF23. Further studies in a greater number of patients will shed more light on the disturbances of the iFGF23, Klotho and C-FGF23 in thalassemia and their possible role in bone disease of such patients.

Efficacy Of Interrupted And Modified Deferasirox Dose Among Paediatric Patients With Β- Thalassemia Major And High Alanine Aminotransferase Level

BACKGROUND

Abnormal liver function tests lead to interruptions of Deferasirox therapy. The aim of this study is to assess the efficacy of deferasirox dose 30 mg /kg /day in maintaining cardiac protective level of serum ferritin of <2500 ng/ml among patients who received interrupted and modified doses.

METHODS

A retrospective cohort study was conducted in Ibn Al Atheer paediatric hospital in Mosul city, Iraq, utilizing the monthly reading of serum ferritin level during the period started in February 2013 to march 2014 using documented patients' records. Group A, patients included thirty-five patients with β- thalassemia major whose Deferasirox dose of 30 mg/kg/day was interrupted and modified due to ≥ 5-fold raise in alanine aminotransferase during any month of the study period. Compared group B patients included 40 children who received constant median deferasirox dose 30 mg/kg/day throughout one year of study period. Serum ferritin and alanine aminotransferase levels were routinely analysed every month among those patients.

RESULTS

Interrupted and modified Deferasirox dose of 30 mg/kg/day significantly (p=0.000) increase the frequency of having mean serum ferritin >2500 ng/ml, and was associated with 55 times relative risk of having mean serum ferritin >2500 ng/ml compared to group B with steady median deferasirox dose.

CONCLUSIONS

Interrupted and modified deferasirox dose of 30 mg/kg/day has a significant adverse effect on cardiac protective level of serum ferritin.

Single-center retrospective study of the effectiveness and toxicity of the oral iron chelating drugs deferiprone and deferasirox

Background

Iron overload, resulting from blood transfusions in patients with chronic anemias, has historically been controlled with regular deferoxamine, but its parenteral requirement encouraged studies of orally-active agents, including deferasirox and deferiprone. Deferasirox, licensed by the US Food and Drug Administration in 2005 based upon the results of randomized controlled trials, is now first-line therapy worldwide. In contrast, early investigator-initiated trials of deferiprone were prematurely terminated after investigators raised safety concerns. The FDA declined market approval of deferiprone; years later, it licensed the drug as “last resort” therapy, to be prescribed only if first-line drugs had failed. We undertook to evaluate the long-term effectiveness and toxicities of deferiprone and deferasirox in one transfusion clinic.

Methods and findings

Under an IRB-approved study, we retrospectively inspected the electronic medical records of consented iron-loaded patients managed between 2009 and 2015 at The University Health Network (UHN), Toronto. We compared changes in liver and heart iron, adverse effects and other outcomes, in patients treated with deferiprone or deferasirox.

Results

Although deferiprone was unlicensed in Canada, one-third (n = 41) of locally-transfused patients had been switched from first-line, licensed therapies (deferoxamine or deferasirox) to regimens of unlicensed deferiprone. The primary endpoint of monitoring in iron overload, hepatic iron concentration (HIC), increased (worsened) during deferiprone monotherapy (mean 10±2–18±2 mg/g; p < 0.0003), exceeding the threshold for life-threatening complications (15 mg iron/g liver) in 50% patients. During deferasirox monotherapy, mean HIC decreased (improved) (11±1–6±1 mg/g; p < 0.0001). Follow-up HICs were significantly different following deferiprone and deferasirox monotherapies (p < 0.0000002). Addition of low-dose deferoxamine (<40 mg/kg/day) to deferiprone did not result in reductions of HIC to <15 mg/g (baseline 20±4 mg/g; follow-up, 18±4 mg/g; p < 0.2) or in reduction in the proportion of patients with HIC exceeding 15 mg/g (p < 0.2). During deferiprone exposure, new diabetes mellitus, a recognized consequence of inadequate iron control, was diagnosed in 17% patients, most of whom had sustained HICs exceeding 15 mg/g for years; one woman died after 13 months of a regimen of deferiprone and low-dose deferasirox. During deferiprone exposure, serum ALT increased over baseline in 65% patients. Mean serum ALT increased 6.6-fold (p < 0.001) often persisting for years. During deferasirox exposure, mean ALT was unchanged (p < 0.84). No significant differences between treatment groups were observed in the proportions of patients estimated to have elevated cardiac iron.

Conclusions

Deferiprone showed ineffectiveness and significant toxicity in most patients. Combination with low doses of first-line therapies did not improve the effectiveness of deferiprone. Exposure to deferiprone, over six years while the drug was unlicensed, in the face of ineffectiveness and serious toxicities, demands review of the standards of local medical practice. The limited scope of regulatory approval of deferiprone, worldwide, should restrict its exposure to the few patients genuinely unable to tolerate the two effective, first-line therapies.

Targeted Co-delivery of the Iron Chelator Deferoxamine and a HIF1α Inhibitor Impairs Pancreatic Tumor Growth

Rapidly growing cancer cells exhibit a strong dependence on iron for their survival. Thus, iron-removing drugs, iron chelators, have potential applications in cancer treatment. Deferoxamine (DFO) is an efficient iron chelator, but its short circulation half-life and ability to induce hypoxia-inducible factor 1α (HIF1α) overexpression restricts its use as an antitumor agent. In the present study, we first found that a pattern of iron-related protein expression favoring higher intracellular iron closely correlates with shorter overall and relapse-free survival in pancreatic cancer patients. We subsequently found that a combination of DFO and the HIF1α inhibitor, lificiguat (also named YC1), significantly enhanced the antitumor efficacy of DFO in vitro. We then employed transferrin receptor 1 (TFR1) targeting liposomes to codeliver DFO and YC1 to pancreatic tumors in a mouse model. The encapsulation of DFO prolonged its circulation time, improved its accumulation in tumor tissues via the enhanced permeability and retention (EPR) effect, and facilitated efficient uptake by cancer cells, which express high level of TFR1. After entering the tumor cells, the encapsulated DFO and YC1 were released to elicit a synergistic antitumor effect in subcutaneous and orthotopic pancreatic cancer xenografts. In summary, our work overcame two major obstacles in DFO-based cancer treatment through a simple liposome-based drug delivery system. This nanoencapsulation and targeting paradigm lays the foundation for future application of iron chelation in cancer therapy.

α-Lipoic Acid Reduces Iron-induced Toxicity and Oxidative Stress in a Model of Iron Overload

Iron toxicity is associated with organ injury and has been reported in various clinical conditions, such as hemochromatosis, thalassemia major, and myelodysplastic syndromes. Therefore, iron chelation therapy represents a pivotal therapy for these patients during their lifetime. The aim of the present study was to assess the iron chelating properties of α-lipoic acid (ALA) and how such an effect impacts on iron overload mediated toxicity. Human mesenchymal stem cells (HS-5) and animals (zebrafish, n = 10 for each group) were treated for 24 h with ferric ammonium citrate (FAC, 120 µg/mL) in the presence or absence of ALA (20 µg/mL). Oxidative stress was evaluated by reduced glutathione content, reactive oxygen species formation, mitochondrial dysfunction, and gene expression of heme oxygenase-1b and mitochondrial superoxide dismutase; organ injury, iron accumulation, and autophagy were measured by microscopical, cytofluorimetric analyses, and inductively coupled plasma‒optical mission Spectrometer (ICP-OES). Our results showed that FAC results in a significant increase of tissue iron accumulation, oxidative stress, and autophagy and such detrimental effects were reversed by ALA treatment. In conclusion, ALA possesses excellent iron chelating properties that may be exploited in a clinical setting for organ preservation, as well as exhibiting a good safety profile and low cost for the national health system.

To chelate or not to chelate in MDS: That is the question!

Myelodysplastic syndromes (MDS) are a heterogeneous group of hemopathies that exhibit physical manifestations with clinical consequences of bone marrow failure and inherent risk of progression to acute myeloid leukemia. Iron overload (IO) is common in MDS due to chronic transfusion support and disease-related alterations in iron metabolism. IO has been conclusively associated with inferior outcomes among MDS patients. Despite lack of randomized trials showing a survival impact of iron chelation therapy (ICT), ICT is recommended by experts and guidelines for select MDS patients with IO and is often used. The availability of effective oral ICT agents has reignited the controversy regarding ICT use in patients with MDS and IO. Here we summarize the studies evaluating the value of ICT in MDS and suggest a practical approach for use of these therapies. We also highlight controversies regarding use of ICT in MDS and discuss some ongoing efforts to answer these questions.

Deferasirox for managing iron overload in people with thalassaemia

BACKGROUND

Thalassaemia is a hereditary anaemia due to ineffective erythropoiesis. In particular, people with thalassaemia major develop secondary iron overload resulting from regular red blood cell transfusions. Iron chelation therapy is needed to prevent long-term complications.Both deferoxamine and deferiprone are effective; however, a review of the effectiveness and safety of the newer oral chelator deferasirox in people with thalassaemia is needed.

OBJECTIVES

To assess the effectiveness and safety of oral deferasirox in people with thalassaemia and iron overload.

SEARCH METHODS

We searched the Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 12 August 2016.We also searched MEDLINE, Embase, the Cochrane Library, Biosis Previews, Web of Science Core Collection and three trial registries: ClinicalTrials.gov; the WHO International Clinical Trials Registry Platform; and the Internet Portal of the German Clinical Trials Register: 06 and 07 August 2015.

SELECTION CRITERIA

Randomised controlled studies comparing deferasirox with no therapy or placebo or with another iron-chelating treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data. We contacted study authors for additional information.

MAIN RESULTS

Sixteen studies involving 1807 randomised participants (range 23 to 586 participants) were included. Twelve two-arm studies compared deferasirox to placebo (two studies) or deferoxamine (seven studies) or deferiprone (one study) or the combination of deferasirox and deferoxamine to deferoxamine alone (one study). One study compared the combination of deferasirox and deferiprone to deferiprone in combination with deferoxamine. Three three-arm studies compared deferasirox to deferoxamine and deferiprone (two studies) or the combination of deferasirox and deferiprone to deferiprone and deferasirox monotherapy respectively (one study). One four-arm study compared two different doses of deferasirox to matching placebo groups.The two studies (a pharmacokinetic and a dose-escalation study) comparing deferasirox to placebo (n = 47) in people with transfusion-dependent thalassaemia showed that deferasirox leads to net iron excretion. In these studies, safety was acceptable and further investigation in phase II and phase III studies was warranted.Nine studies (1251 participants) provided data for deferasirox versus standard treatment with deferoxamine. Data suggest that a similar efficacy can be achieved depending on the ratio of doses of deferoxamine and deferasirox being compared. In the phase III study, similar or superior efficacy for the intermediate markers ferritin and liver iron concentration (LIC) could only be achieved in the highly iron-overloaded subgroup at a mean ratio of 1 mg of deferasirox to 1.8 mg of deferoxamine corresponding to a mean dose of 28.2 mg per day and 51.6 mg per day respectively. The pooled effects across the different dosing ratios are: serum ferritin, mean difference (MD) 454.42 ng/mL (95% confidence interval (CI) 337.13 to 571.71) (moderate quality evidence); LIC evaluated by biopsy or SQUID, MD 2.37 mg Fe/g dry weight (95% CI 1.68 to 3.07) (moderate quality evidence) and responder analysis, LIC 1 to < 7 mg Fe/g dry weight, risk ratio (RR) 0.80 (95% CI 0.69 to 0.92) (moderate quality evidence). The substantial heterogeneity observed could be explained by the different dosing ratios. Data on mortality (low quality evidence) and on safety at the presumably required doses for effective chelation therapy are limited. Patient satisfaction was better with deferasirox among those who had previously received deferoxamine treatment, RR 2.20 (95% CI 1.89 to 2.57) (moderate quality evidence). The rate of discontinuations was similar for both drugs (low quality evidence).For the remaining comparisons in people with transfusion-dependent thalassaemia, the quality of the evidence for outcomes assessed was low to very low, mainly due to the very small number of participants included. Four studies (205 participants) compared deferasirox to deferiprone; one of which (41 participants) revealed a higher number of participants experiencing arthralgia in the deferiprone group, but due to the large number of different types of adverse events reported and compared this result is uncertain. One study (96 participants) compared deferasirox combined with deferiprone to deferiprone with deferoxamine. Participants treated with the combination of the oral iron chelators had a higher adherence compared to those treated with deferiprone and deferoxamine, but no participants discontinued the study. In the comparisons of deferasirox versus combined deferasirox and deferiprone and that of deferiprone versus combined deferasirox and deferiprone (one study, 40 participants), and deferasirox and deferoxamine versus deferoxamine alone (one study, 94 participants), only a few patient-relevant outcomes were reported and no significant differences were observed.One study (166 participants) included people with non-transfusion dependent thalassaemia and compared two different doses of deferasirox to placebo. Deferasirox treatment reduced serum ferritin, MD -306.74 ng/mL (95% CI -398.23 to -215.24) (moderate quality evidence) and LIC, MD -3.27 mg Fe/g dry weight (95% CI -4.44 to -2.09) (moderate quality evidence), while the number of participants experiencing adverse events and rate of discontinuations (low quality evidence) was similar in both groups. No participant died, but data on mortality were limited due to a follow-up period of only one year (moderate quality evidence).

AUTHORS' CONCLUSIONS

Deferasirox offers an important treatment option for people with thalassaemia and secondary iron overload. Based on the available data, deferasirox does not seem to be superior to deferoxamine at the usually recommended ratio of 1 mg of deferasirox to 2 mg of deferoxamine. However, similar efficacy seems to be achievable depending on the dose and ratio of deferasirox compared to deferoxamine. Whether this will result in similar efficacy and will translate to similar benefits in the long term, as has been shown for deferoxamine, needs to be confirmed. Data from randomised controlled trials on rare toxicities and long-term safety are still limited. However, after a detailed discussion of the potential benefits and risks, deferasirox could be offered as the first-line option to individuals who show a strong preference for deferasirox, and may be a reasonable treatment option for people showing an intolerance or poor adherence to deferoxamine.

Development of hydroxybenzoic-based platforms as a solution to deliver dietary antioxidants to mitochondria

Oxidative stress and mitochondrial dysfunction have been associated with metabolic and age-related diseases. Thus, the prevention of mitochondrial oxidative damage is nowadays a recognized pharmacological strategy to delay disease progression. Epidemiological studies suggested an association between the consumption of polyphenol-rich diet and the prevention of different pathologies, including diseases with a mitochondrial etiology. The development of mitochondrial-targeted antioxidants based on dietary antioxidants may decrease mitochondrial oxidative damage. Herein, we report the design and synthesis of two new mitochondriotropic antioxidants based on hydroxybenzoic acids (AntiOxBENs). The results obtained showed that the novel antioxidants are accumulated inside rat liver mitochondria driven by the organelle transmembrane electric potential and prevented lipid peroxidation, exhibiting low toxicity. Some of the observed effects on mitochondrial bioenergetics resulted from an increase of proton leakage through the mitochondrial inner membrane. The new derivatives present a higher lipophilicity than the parent compounds (protocatechuic and gallic acids) and similar antioxidant and iron chelating properties. AntiOxBENs are valid mitochondriotropic antioxidant prototypes, which can be optimized and used in a next future as drug candidates to prevent or slow mitochondrial oxidative stress associated to several pathologies.

Effect of the oral iron chelator deferiprone in diabetic nephropathy rats

BACKGROUND

The aim of the present study was to investigate the effects of the iron chelator deferiprone in diabetic nephropathy (DN) rats and the mechanisms involved.

METHODS

Thirty-two male Wistar rats (180-220 g, 6 weeks old) were randomly divided into a control group, a DN group and two DN groups treated with either 50 or 100 mg/kg per day deferiprone. The DN group was established by feeding of a high-carbohydrate-fat diet and injection of 35 mg/kg streptozotocin into the vena caudalis. The duration of deferiprone treatment was 20 weeks. Histopathological changes were detected by hematoxylin-eosin and Masson staining, as well as transmission electron microscopy. Levels of nuclear factor (NF)-κB, monocyte chemotactic protein (MCP)-1, matrix metalloproteinase (MMP)-9, tissue-specific inhibitor of metalloproteinase (TIMP)-1, cyclo-oxygenase (COX)-2, and nitrotyrosine were determined in kidney tissues using reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and immunohistochemistry.

RESULTS

Histopathological observations showed that deferiprone treatment alleviated inflammation infiltrates and collagenous fibrosis in DN rats. Results from RT-PCR and western blotting indicated that deferiprone inhibited the expression of NF-κB, MCP-1, COX-2, and nitrotyrosine, which were overexpressed in DN rats. Immunohistochemistry showed that the mechanism of deferiprone action may involve regulation of MMP-9 and TIMP-1. Decreased MMP-9 expression and increased TIMP-1 expression in DN rats were significantly promoted and inhibited by deferiprone, respectively.

CONCLUSION

Iron chelation by oral deferiprone has a renoprotective effect in DN rats by relieving oxidative stress, inflammation, and fibrosis, which is related to the cytokines NF-κB, MCP-1, MMP-9, TIMP-1, COX-2, and nitrotyrosine.

Chemical features of in use and in progress chelators for iron overload

An excessive amount of iron may become extremely toxic both for its ability to generate reactive oxygen species, and for the lack of regulatory mechanisms for iron excretion in humans. Chelation therapy has been introduced in clinical practice in the 1970's to defend thalassemia patients from the effects of iron overload and it has dramatically changed both life expectancy and quality of life. The disadvantages of the drugs in clinical use make the research for new, more suitable iron chelating agents, urgent. This review defines the requirements of an iron chelator, then points out the principal chemical features of the iron chelators in use. Finally, a survey on the last ten years of the literature relative to iron chelators is done, and the most interesting ligands are presented, with particular emphasis to those that reached clinical trials.

Local delivery of iron chelators reduces in vivo remodeling of a calcium phosphate bone graft substitute

Iron chelators are known activators of the Hypoxia Includible Factor-1α (HIF-1α) pathway, a critical cellular pathway involved in angiogenic responses to hypoxia. Local delivery of these chelators has shown promise in bone tissue engineering strategies by inducing angiogenesis and osteogenesis. Hypoxic microenvironments are also a stimulus for osteoclast differentiation and resorptive activity, a process likely mediated by HIF-1α. In vitro, low doses of the iron chelator Deferoxamine (DFO) has shown to induce HIF-1α mediated osteoclast formation and function. However other studies have proposed an opposite in vitro effect likely through HIF independent mechanisms. To investigate use of these medications in bioceramic based bone tissue engineering strategies this study aimed to determine the in vivo effect of local delivery of iron chelators on bioceramic remodeling. A non-weight bearing cranial onlay model was used to assess monetite resorption and new bone formation in the presence or absence of a repeated delivery of two iron chelators, DFO and 1,10 Phenanthroline (PHT) at doses known to induce HIF. We found a marked reduction graft resorption and remodeling associated with iron chelation. This was correlated to a 3-fold reduction in osteoclast number at the bone graft interface. Iron is needed for mitochondrial biogenesis during osteoclastic differentiation and reducing extracellular iron levels may inhibit this process and possibly overpower any HIF induced osteoclast formation. Our findings suggest that these inexpensive and widely available molecules may be used to locally reduce bioceramic scaffold resorption and encourages future investigations of iron chelators as bone anti-resorptive agents in other clinical contexts.

STATEMENT OF SIGNIFICANCE

Low doses of iron chelators can induce angiogenesis and osteogenesis in repairing bone by stimulating the oxygen sensitive gene; hypoxia inducible factor. These medications have potential to augment bioceramic based bone tissue engineering strategies without the downsides of protein-based growth factors. HIF activation is also known to stimulate osteoclast-mediated resorption and could potentially accelerate remodeling of biocermaics, however we have shown that the local delivery of iron chelation at doses known to induce HIF resulted in a reduction of monetite resorption and a significant decrease in osteoclast number at the bone graft interface. This maybe due to HIF independent mechanism. This is the first study to show a local effect of iron chelators in vivo on osteoclast-mediated resorption. This opens the potential of further study of these bifunctional medications to modulate resorption of biocermaics in environments where a prolonged presence of material is desired for graft site stability. Moreover these safe widely used medications can be explored to locally reduce osteoclasts in pathological bone resorption.

[IRON OVERLOAD: BETTER UNDERSTANDING, BETTER CARE]

Chronic iron overload, either of genetic (hemochromatoses) or acquired (transfusions) origin, leads to frequent disorders, affecting both the quality of life and life expectancy. Major recent advances in the knowledge of iron metabolism, together with advances in biology, imaging and drug design have already significantly improved the diagnostic and therapeutic approaches. These conceptual and technological ameliorations should, in the near future, continue to benefit the clinical management of iron overloaded patients.

Iron Chelation in Thalassemia Major

PURPOSE

Iron chelation has improved survival and quality of life of patients with thalassemia major. there are currently 3 commercially available iron-chelating drugs with different pharmacokinetic and pharmacodynamic activity. The choice of adequate chelation treatment should be tailored to patient needs and based on up-to-date scientific evidence.

METHODS

A review of the most recent literature was performed.

FINDINGS

The ability of the chelators to bind the redox active component of iron, labile plasma iron, is crucial for protecting the cells. Chelation therapy should be guided by magnetic resonance imaging that permits the tailoring of therapy according to the needs of the patient because different chelators preferentially clear iron from different sites. Normal levels of body iron seem to decrease the need for hormonal and cardiac therapy.

IMPLICATIONS

The 3 chelators currently available have different benefits, different safety profiles, and different acceptance on the part of the patients. Good-quality, well-designed, randomized, long-term clinical trials continue to be needed.

Reduction of Oxidative Damage and Inflammatory Response in the Diaphragm Muscle of mdx Mice Using Iron Chelator Deferoxamine

Oxidative stress and inflammatory processes strongly contribute to pathogenesis in Duchenne muscular dystrophy (DMD). Based on evidence that excess iron may increase oxidative stress and contribute to the inflammatory response, we investigated whether deferoxamine (DFX), a potent iron chelating agent, reduces oxidative stress and inflammation in the diaphragm (DIA) muscle of mdx mice (an experimental model of DMD). Fourteen-day-old mdx mice received daily intraperitoneal injections of DFX at a dose of 150 mg/kg body weight, diluted in saline, for 14 days. C57BL/10 and control mdx mice received daily intraperitoneal injections of saline only, for 14 days. Grip strength was evaluated as a functional measure, and blood samples were collected for biochemical assessment of muscle fiber degeneration. In addition, the DIA muscle was removed and processed for histopathology and Western blotting analysis. In mdx mice, DFX reduced muscle damage and loss of muscle strength. DFX treatment also resulted in a significant reduction of dystrophic inflammatory processes, as indicated by decreases in the inflammatory area and in NF-κB levels. DFX significantly decreased oxidative damage, as shown by lower levels of 4-hydroxynonenal and a reduction in dihydroethidium staining in the DIA muscle of mdx mice. The results of the present study suggest that DFX may be useful in therapeutic strategies to ameliorate dystrophic muscle pathology, possibly via mechanisms involving oxidative and inflammatory pathways.

Deferasirox-TAT(47-57) peptide conjugate as a water soluble, bifunctional iron chelator with potential use in neuromedicine

Deferasirox (DFX), an orally active and clinically approved iron chelator, is being used extensively for the treatment of iron overload. However, its water insolubility makes it cumbersome for practical use. In addition to this, the low efficacy of DFX to remove brain iron prompted us to synthesize and evaluate a DFX-TAT(47-57) peptide conjugate for its iron chelation properties and permeability across RBE4 cell line, an in vitro model of the blood-brain barrier. The water-soluble conjugate was able to remove labile iron from buffered solution as well as from iron overloaded sera, and the permeability of DFX-TAT(47-57) conjugate into RBE4 cells was not affected compared to parent deferasirox. The iron bound conjugate was also able to translocate through the cell membrane.

Long-term effects of an oral iron chelator, deferasirox, in hemodialysis patients with iron overload

Background/Purpose Retention of excess iron from transfused blood in organs in patients with renal anemia may lead to various systemic complications. Iron chelating agents such as deferasirox (DFX) decrease such iron overload. This study assessed the efficacy, safety, and tolerability of DFX in hemodialysis (HD) patients with iron overload. Methods We retrospectively (February 2008 to June 2012) reviewed data for eight HD patients with end-stage renal disease who were prescribed DFX (15 mg/kg/day) for transfusion-induced iron overload. Baseline and post-treatment levels of hematocrit, ferritin, erythropoietin (EPO), transferrin saturation (TSAT), total and unsaturated iron-binding capacity (TIBC and UIBC, respectively), and blood transfusion volumes were measured. Treatment efficacy was evaluated by observing changes in ferritin and TSAT during the study period; monthly EPO doses and blood transfusions were also recorded. Safety was evaluated in the form of adverse events. Results DFX administration caused statistically significant reductions in TSAT (68.2-49.2%; P = 0.036) and ferritin (3133.1-1215.6 ng/ml; P = 0.017). Significant post-treatment increases in UIBC (63.3-196.6 µg/dl; P = 0.018) and TIBC (210.0-422.4 µg/dl; P = 0.012) were also observed. While there were no significant differences in hematocrit values or EPO requirements after treatment, significant reductions in average monthly transfusion volumes (P = 0.026) were recorded. DFX was generally well tolerated; common adverse effects included nausea, vomiting, diarrhea, and abdominal pain. Conclusion DFX significantly improved iron metabolism in HD patients with iron overload and had an acceptable frequency of adverse effects.

Spin density projection-assisted R2 magnetic resonance imaging of the liver in the management of body iron stores in patients receiving multiple red blood cell transfusions: an audit and retrospective study in South Australia

AIM

To assess the impact of non-invasive monitoring of liver iron concentration (LIC) on management of body iron stores in patients receiving multiple blood transfusions.

METHOD

A retrospective audit was conducted on clinical data from 40 consecutive subjects with haemolytic anaemias or ineffective haematopoiesis who had been monitored non-invasively for LIC over a period of at least 1 year. LIC was measured with spin density projection-assisted proton transverse relaxation rate-magnetic resonance imaging.

RESULTS

Nineteen clinical decisions were explicitly documented in the case notes as being based on LIC results. Decisions comprised initiation of chelation therapy, increasing chelator dose, decreasing chelator dose and change of mode of delivery of deferioxamine from subcutaneous to intravenous. The geometrical mean LIC for the cohort dropped significantly (P= 0.008) from 6.8 mg Fe/g dry tissue at initial measurement to 4.8 mg Fe/g dry tissue at final measurement. The proportion of subjects with LIC in the range associated with greatly increased risk of cardiac disease and death (>15 mg Fe/g dry tissue) dropped significantly (P= 0.01) from 14 of 40 subjects at initial measurement to 5 of 40 subjects at final measurement. No significant changes in the geometrical mean of serum ferritin or the proportion of subjects with serum ferritin above 2500 or 1500 µg/L were observed.

CONCLUSIONS

The data are consistent with previous observations that introduction of non-invasive monitoring of LIC can contribute to a decreased body iron burden through improved clinical decision making and improved feedback to patients and hence improved adherence to chelation therapy.

[Development of acute pure red cell aplasia after deferasirox administration in two cases of myelodysplastic syndrome]

Cases 1 and 2 were 55- and 68-year-old males, respectively. Both were administered deferasirox (DFX) because they received red blood cell transfusions regularly as treatment for myelodysplastic syndrome refractory anemia. DFX administrations were stopped on the 22nd day in case 1 and on the 78th day in case 2 because significantly reduced hemoglobin values and reticulocyte counts were observed. Bone marrow examinations showed pure red cell aplasia in both cases. In case 1, the reticulocyte ratio recovered to the value before drug administration 21 days after drug withdrawal. In case 2, it started increasing on the 14th day, and had recovered to the value before drug administration by the 42nd day after drug withdrawal. Human parvovirus B19 infections were negative in both cases. Both cases were thought to have drug-induced pure red cell aplasia, probably due to DFX. This drug should be used carefully with regular follow-ups of the reticulocyte count.

A 1-year randomized controlled trial of deferasirox vs deferoxamine for myocardial iron removal in β-thalassemia major (CORDELIA)

Randomized comparison data on the efficacy and safety of deferasirox for myocardial iron removal in transfusion dependent patients are lacking. CORDELIA was a prospective, randomized comparison of deferasirox (target dose 40 mg/kg per day) vs subcutaneous deferoxamine (50-60 mg/kg per day for 5-7 days/week) for myocardial iron removal in 197 β-thalassemia major patients with myocardial siderosis (T2* 6-20 milliseconds) and no signs of cardiac dysfunction (mean age, 19.8 years). Primary objective was to demonstrate noninferiority of deferasirox for myocardial iron removal, assessed by changes in myocardial T2* after 1 year using a per-protocol analysis. Geometric mean (Gmean) myocardial T2* improved with deferasirox from 11.2 milliseconds at baseline to 12.6 milliseconds at 1 year (Gmeans ratio, 1.12) and with deferoxamine (11.6 milliseconds to 12.3 milliseconds; Gmeans ratio, 1.07). The between-arm Gmeans ratio was 1.056 (95% confidence interval [CI], 0.998, 1.133). The lower 95% CI boundary was greater than the prespecified margin of 0.9, establishing noninferiority of deferasirox vs deferoxamine (P = .057 for superiority of deferasirox). Left ventricular ejection fraction remained stable in both arms. Frequency of drug-related adverse events was comparable between deferasirox (35.4%) and deferoxamine (30.8%). CORDELIA demonstrated the noninferiority of deferasirox compared with deferoxamine for myocardial iron removal. This trial is registered at www.clinicaltrials.gov as #NCT00600938.

Combined therapy of iron chelator and antioxidant completely restores brain dysfunction induced by iron toxicity

Background

Excessive iron accumulation leads to iron toxicity in the brain; however the underlying mechanism is unclear. We investigated the effects of iron overload induced by high iron-diet consumption on brain mitochondrial function, brain synaptic plasticity and learning and memory. Iron chelator (deferiprone) and antioxidant (n-acetyl cysteine) effects on iron-overload brains were also studied.

Methodology

Male Wistar rats were fed either normal diet or high iron-diet consumption for 12 weeks, after which rats in each diet group were treated with vehicle or deferiprone (50 mg/kg) or n-acetyl cysteine (100 mg/kg) or both for another 4 weeks. High iron-diet consumption caused brain iron accumulation, brain mitochondrial dysfunction, impaired brain synaptic plasticity and cognition, blood-brain-barrier breakdown, and brain apoptosis. Although both iron chelator and antioxidant attenuated these deleterious effects, combined therapy provided more robust results.

Conclusion

In conclusion, this is the first study demonstrating that combined iron chelator and anti-oxidant therapy completely restored brain function impaired by iron overload.

[Iron metabolism and its role in traumatic disease]

The article reviews recent studies of iron exchange and its role in a traumatic disease and traumatic shock. The review stresses a relationship of iron metabolism disturbance with free radical oxidation, lipid peroxidation and multiple organ dysfunctions. The article deals with data of unbound iron collect mechanisms, ways of endotoxemia activation, haemostasis and haemodynamics disturbance proving the role of iron in a multiple organ dysfunctions during traumatic disease.

Role of iron in lung injury-induced by hyperoxia

Iron is essential to life due to its unusual flexibility in serving as both an electron donor and acceptor. However, free iron can damage tissues by catalyzing the conversion of hydrogen peroxide to free-radical ions that attack lipids, proteins and DNA. Hyperoxia-induced lung injury (HILI) occurs when breathing elevated partial pressure of oxygen (usually > 0.5 atmospheres absolute) for extended periods. A few studies have shown that iron and proteins related to iron metabolism are closely related to HILI, and iron chelation may exert protective effects on HILI. As a rate-limiting enzyme in the degradation of heme, heme oxygenases (HOs) play a crucial role in the iron metabolism. Although some studies have been conducted to investigate the role of HOs in the pathogenesis of HILI, findings still conflict, and HOs of different isoforms may function differently in the pathogenesis of HILI. On the available findings, there might be a beneficial threshold of HO-1 expression in HILI. More studies are required to confirm the above findings and to provide evidence for the clinical treatment of HILI by iron chelation.

Compliance and satisfaction with deferasirox (Exjade®) compared with deferoxamine in patients with transfusion-dependent beta-thalassemia

OBJECTIVE

The current standard option for iron chelation therapy (ICT) in transfusion-dependent patients with beta-thalassemia is deferoxamine (DFO). We aimed to compare the compliance with DFO vs. deferasirox (Exjade®), a novel oral iron chelator, in patients with transfusion-dependent beta-thalassemia.

METHODS

In this cross-sectional study, 220 patients from Southern Iran who were receiving DFO or Exjade® for the last 2 years were investigated in 2012. Satisfaction, compliance, convenience, and life disturbances of the patients with ICT were evaluated. Assessments were performed at four different occasions during 1 year.

RESULTS

According to the results, 114 patients received treatment with DFO and 106 patients were treated with Exjade®. In comparison with the patients who were treated with DFO, those receiving Exjade® reported a significantly higher rate of compliance and convenience (P < 0.05). However, no significant difference was observed between the two groups regarding their satisfaction (P > 0.05). In the DFO group, 44.9% of the patients reported irritation and pain at the injection site.

CONCLUSIONS

Considering higher rate of compliance and convenience with Exjade® and the comparable efficacy of these two modalities of ICT documented in previous studies, Exjade® can be used as a preferable choice of ICT in iron-overload patients with beta-thalassemia.

The oral iron chelator deferasirox might improve survival in allogeneic hematopoietic cell transplant (alloHSCT) recipients with transfusional iron overload

INTRODUCTION

Iron overload (IO) has been shown to be an important cause of mortality and morbidity in patients who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT). This study aimed to evaluate the possible effect of oral iron-chelation treatment (deferasirox) on survival in alloHSCT recipients in the posttransplant period.

MATERIALS AND METHODS

A total of 80 alloHSCT recipients with IO were analyzed, retrospectively. Pretransplant and posttransplant data were obtained from the patients' files. Patients were divided into two groups. Group 1; patients who did not receive any chelator treatment due to side effects or compliance problems. These patients were treated by phlebotomy. Group 2 consisted of patients who received deferasirox treatment.

RESULTS

The median treatment duration with deferasirox was 122 days (min-max:91-225). The iron chelating treatment significantly reduced serum ferritin levels administered at a dosage of 20-30 mg/kg/day (p<0.001). The median OS in Group 1 was found 16.0 (min-max:1.0-63.0) months and 25.0 (min-max:3.0-72.0) months in Group 2. In univariate and multivariate analysis, patients in Group 1 showed poorer OS compared to those in Group 2 with an increase in risk of death (HR:3.22, min-max:1.67-6.23, p=0.001 and HR:3.51,, min-max:1.75-6.99, p<0.001; respectively). The median DFS in Group 1 was found 11.0 (min-max:3.0-24.0) months and 22.0 (min-max:8.0-43.0) months in Group 2. The difference was found statistically significant (p=0.023). The other factors that we found significant difference in multivariate analysis between groups were; presence of acute GVHD (patients with aGVHD had increased risk of death compared to patients without aGVHD (HR:2.49, min-max: 1.32-4.69, p=0.005), chronic GVHD (HR:2.57, min-max:1.23-5.41, p=0.013), median interval to tx (HR: 2.23, min-max:1.17-4.26, p=0.015) and HLA match (HR:3.01, min-max:1.35-6.73, p=0.007) CONCLUSION: Oral deferasirox (Exjade) treatment may improve survival in patients with iron overload who underwent alloHSCT.

Targeting dysregulation of brain iron homeostasis in Parkinson's disease by iron chelators

Brain iron accumulation has been implicated in a host of chronic neurological diseases, including Parkinson's disease (PD). The elevated iron levels observed in the substantia nigra of PD subjects have been suggested to incite the generation of reactive oxygen species and intracellular α-synuclein aggregation, terminating in the oxidative neuronal destruction of this brain area. Thus, elucidation of the molecular mechanisms involved in iron dysregulation and oxidative stress-induced neurodegeneration is a crucial step in deciphering PD pathology and in developing novel iron-complexing compounds aimed at restoring brain iron homeostasis and attenuating neurodegeneration. This review discusses the involvement of dysregulation of brain iron homeostasis in PD pathology, with an emphasis on the potential effectiveness of naturally occurring compounds and novel iron-chelating/antioxidant therapeutic hybrid molecules, exerting a spectrum of neuroprotective interrelated activities: antioxidant/monoamine oxidase inhibition, activation of the hypoxia-inducible factor (HIF)-1 signaling pathway, induction of HIF-1 target iron-regulatory and antioxidative genes, and inhibition of α-synuclein accumulation and aggregation.

Desferrioxamine mesylate for managing transfusional iron overload in people with transfusion-dependent thalassaemia

BACKGROUND

Thalassaemia major is a genetic disease characterised by a reduced ability to produce haemoglobin. Management of the resulting anaemia is through red blood cell transfusions.Repeated transfusions result in an excessive accumulation of iron in the body (iron overload), removal of which is achieved through iron chelation therapy. Desferrioxamine mesylate (desferrioxamine) is one of the most widely used iron chelators. Substantial data have shown the beneficial effects of desferrioxamine, although adherence to desferrioxamine therapy is a challenge. Alternative oral iron chelators, deferiprone and deferasirox, are now commonly used. Important questions exist about whether desferrioxamine, as monotherapy or in combination with an oral iron chelator, is the best treatment for iron chelation therapy.

OBJECTIVES

To determine the effectiveness (dose and method of administration) of desferrioxamine in people with transfusion-dependent thalassaemia.To summarise data from trials on the clinical efficacy and safety of desferrioxamine for thalassaemia and to compare these with deferiprone and deferasirox.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register. We also searched MEDLINE, EMBASE, CENTRAL (The Cochrane Library), LILACS and other international medical databases, plus ongoing trials registers and the Transfusion Evidence Library (www.transfusionevidencelibrary.com). All searches were updated to 5 March 2013.

SELECTION CRITERIA

Randomised controlled trials comparing desferrioxamine with placebo, with another iron chelator, or comparing two schedules or doses of desferrioxamine, in people with transfusion-dependent thalassaemia.

DATA COLLECTION AND ANALYSIS

Six authors working independently were involved in trial quality assessment and data extraction. For one trial, investigators supplied additional data upon request.

MAIN RESULTS

A total of 22 trials involving 2187 participants (range 11 to 586 people) were included. These trials included eight comparisons between desferrioxamine alone and deferiprone alone; five comparisons between desferrioxamine combined with deferiprone and deferiprone alone; eight comparisons between desferrioxamine alone and desferrioxamine combined with deferiprone; two comparisons of desferrioxamine with deferasirox; and two comparisons of different routes of desferrioxamine administration (bolus versus continuous infusion). Overall, few trials measured the same or long-term outcomes. Seven trials reported cardiac function or liver fibrosis as measures of end organ damage; none of these included a comparison with deferasirox.Five trials reported a total of seven deaths; three in patients who received desferrioxamine alone, two in patients who received desferrioxamine and deferiprone. A further death occurred in a patient who received deferiprone in another who received deferasirox alone. One trial reported five further deaths in patients who withdrew from randomised treatment (deferiprone with or without desferrioxamine) and switched to desferrioxamine alone.One trial planned five years of follow up but was stopped early due to the beneficial effects of a reduction in serum ferritin levels in those receiving combined desferrioxamine and deferiprone treatment compared with deferiprone alone. The results of this and three other trials suggest an advantage of combined therapy with desferrioxamine and deferiprone over monotherapy to reduce iron stores as measured by serum ferritin. There is, however, no evidence for the improved efficacy of combined desferrioxamine and deferiprone therapy against monotherapy from direct or indirect measures of liver iron.Earlier trials measuring the cardiac iron load indirectly by measurement of the magnetic resonance imaging T2* signal had suggested deferiprone may reduce cardiac iron more quickly than desferrioxamine. However, meta-analysis of two trials showed a significantly lower left ventricular ejection fraction in patients who received desferrioxamine alone compared with those who received combination therapy using desferrioxamine with deferiprone.Adverse events were recorded by 18 trials. These occurred with all treatments, but were significantly less likely with desferrioxamine than deferiprone in one trial, relative risk 0.45 (95% confidence interval 0.24 to 0.84) and significantly less likely with desferrioxamine alone than desferrioxamine combined with deferiprone in two other trials, relative risk 0.33 (95% confidence interval 0.13 to 0.84). In particular, four studies reported permanent treatment withdrawal due to adverse events from deferiprone; only one of these reported permanent withdrawals associated with desferrioxamine. Adverse events also occurred at a higher frequency in patients who received deferasirox than desferrioxamine in one trial. Eight trials reported local adverse reactions at the site of desferrioxamine infusion including pain and swelling. Adverse events associated with deferiprone included joint pain, gastrointestinal disturbance, increases in liver enzymes and neutropenia; adverse events associated with deferasirox comprised increases in liver enzymes and renal impairment. Regular monitoring of white cell counts has been recommended for deferiprone and monitoring of liver and renal function for deferasirox.In summary, desferrioxamine and the oral iron chelators deferiprone and deferasirox produce significant reductions in iron stores in transfusion-dependent, iron-overloaded people. There is no evidence from randomised clinical trials to suggest that any one of these has a greater reduction of clinically significant end organ damage, although in two trials, combination therapy with desferrioxamine and deferiprone showed a greater improvement in left ventricular ejection fraction than desferrioxamine used alone.

AUTHORS' CONCLUSIONS

Desferrioxamine is the recommended first-line therapy for iron overload in people with thalassaemia major and deferiprone or deferasirox are indicated for treating iron overload when desferrioxamine is contraindicated or inadequate. Oral deferasirox has been licensed for use in children aged over six years who receive frequent blood transfusions and in children aged two to five years who receive infrequent blood transfusions. In the absence of randomised controlled trials with long-term follow up, there is no compelling evidence to change this conclusion.Worsening iron deposition in the myocardium in patients receiving desferrioxamine alone would suggest a change of therapy by intensification of desferrioxamine treatment or the use of desferrioxamine and deferiprone combination therapy.Adverse events are increased in patients treated with deferiprone compared with desferrioxamine and in patients treated with combined deferiprone and desferrioxamine compared with desferrioxamine alone. People treated with all chelators must be kept under close medical supervision and treatment with deferiprone or deferasirox requires regular monitoring of neutrophil counts or renal function respectively. There is an urgent need for adequately-powered, high-quality trials comparing the overall clinical efficacy and long-term outcomes of deferiprone, deferasirox and desferrioxamine.

Antioxidant activity of different parts of Tetrataenium lasiopetalum

CONTEXT

In Iranian traditional medicine, different species of the genus Tetrataenium are used as antiseptic, spice and food additives.

OBJECTIVE

The present study examined the possible antioxidant effects of hydro-alcoholic extracts of different parts of Tetrataenium lasiopetalum (Boiss.) Manden (Apiaceae).

MATERIALS AND METHODS

Laminas, stems, petioles, fruits, peduncles and flowers of T. lasiopetalum were collected, dried and then extracted by ethanol and water (70:30). Antioxidant activities of extracts were examined by employing different in vitro assays, i.e., 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating, reducing power activities and hemoglobin-induced linoleic acid system. Also, total phenolic and flavonoid contents of the extracts were evaluated.

RESULTS

Hydro-alcoholic extract of T. lasiopetalum flower showed the highest activity in scavenging of DPPH (IC50 = 170 ± 7 μg/mL). In metal chelating assay, lamina extract possesses a better iron ion chelating activity than other extracts (230 ± 10 μg/mL). Lamina hydro-alcoholic extract demonstrated better activity in reducing the power and hemoglobin-induced linoleic acid system than other parts of T. lasiopetalum.

DISCUSSION AND CONCLUSION

These results showed the antioxidant activity of different parts of T. lasiopetalum based on its usage in traditional medicine.

A double-blind, randomized pilot trial of chromium picolinate for binge eating disorder: results of the Binge Eating and Chromium (BEACh) study

OBJECTIVE

Chromium treatment has been shown to improve mood, appetite, and glucose regulation in various psychiatric and medical patient populations. The authors propose that chromium may be useful in the treatment of binge eating disorder (BED).

METHOD

Twenty-four overweight adults with BED were enrolled in a 6-month double-blind placebo-controlled trial and randomly assigned to receive either 1000mcg chromium/day ("high dose"; n=8) or 600mcg chromium/day ("moderate dose"; n=9) as chromium picolinate or placebo (n=7). Mixed linear regression models were used to estimate mean change in binge frequency and related psychopathology, weight, symptoms of depression, and fasting glucose.

RESULTS

Fasting glucose was significantly reduced in both chromium groups compared to the placebo group; similarly, numerically, but not significantly, greater reductions in binge frequency, weight, and symptoms of depression were observed in those treated with chromium versus placebo, although statistical power was limited in this pilot trial. For fasting glucose, the findings suggest a dose response with larger effects in the high dose compared to moderate dose group.

CONCLUSION

These initial findings support further larger trials to determine chromium's efficacy in maintaining normal glucose regulation, reducing binge eating and related psychopathology, promoting modest weight loss, and reducing symptoms of depression in individuals with BED. Studies designed to link the clinical effects of chromium with changes in underlying insulin, serotonin, and dopamine pathways may be especially informative. If efficacious, chromium supplementation may provide a useful, low-cost alternative to or augmentation strategy for selective serotonin reuptake inhibitors, which have partial efficacy in BED. ClinicalTrials.gov NCT00904306.

Lipophilic adamantyl- or deferasirox-based conjugates of desferrioxamine B have enhanced neuroprotective capacity: implications for Parkinson disease

Parkinson disease (PD) is a neurodegenerative disease characterized by death of dopaminergic neurons in the substantia nigra region of the brain. Iron content is also elevated in this region in PD and is implicated in the pathobiology of the disease. Desferrioxamine B (DFOB) is a high-affinity iron chelator and has shown efficacy in animal models of Parkinson disease. The high water solubility of DFOB, however, attenuates its ability to enter the brain. In this study, we have conjugated DFOB to derivatives of adamantane or the clinical iron chelator deferasirox to produce lipophilic compounds designed to increase the bioavailability of DFOB to brain cells. We found that the novel compounds are highly effective in preventing iron-mediated paraquat and hydrogen peroxide toxicity in neuronal-like BE2-M17 dopaminergic cells, primary neurons, and iron-loaded or glutathione-depleted primary astrocytes. The compounds also alleviated paraquat toxicity in BE2-M17 cells that express the PD-causing A30P mutation of α-synuclein. This protection was ∼66-fold more potent than DFOB alone and also more effective than other cell-permeative metal chelators, clioquinol and phenanthroline. These results demonstrate that increasing the bioavailability of DFOB through the conjugation of lipophilic fragments greatly enhances its protective capacity. These novel compounds have potential as therapeutics for the treatment of PD and other conditions of Fe dyshomeostasis.

Effectiveness of oral iron chelator treatment with deferasirox in an aceruloplasminemia patient with a novel ceruloplasmin gene mutation

A 59-year-old man presented with refractory anemia, choreoathetosis in the left upper extremity, an unsteady gait and cognitive dysfunction. The laboratory findings showed a marked decrease in ceruloplasmin. Magnetic resonance images revealed iron deposition in the brain and visceral organs. Iron accumulation was also observed in hepatocytes. Genetic analyses of the ceruloplasmin gene revealed a novel homozygous mutation of c.2185 delC in exon 12. The oral chelator deferasirox was effective in treating the left-side choreoathetosis and unsteady gait. Providing early treatment using deferasirox may be useful for preventing the progression of symptomatic neurological dysfunction.

Long-term use of deferiprone significantly enhances left-ventricular ejection function in thalassemia major patients

A multicenter randomized open-label long-term sequential deferiprone–deferoxamine (DFP-DFO) versus DFP alone trial (sequential DFP-DFO) performed in patients with thalassemia major (TM) was retrospectively reanalyzed to assess the variation in the left ventricular ejection fraction (LVEF) [1].

Deferasirox treatment of iron-overloaded chelation-naïve and prechelated patients with myelodysplastic syndromes in medical practice: results from the observational studies eXtend and eXjange

EXtend and eXjange were prospective, 1-yr, non-interventional, observational, multicentre studies that investigated deferasirox, a once-daily oral iron chelator, in iron-overloaded chelation-naïve and prechelated patients with myelodysplastic syndromes (MDS), respectively, treated in the daily-routine setting of office-based physicians. No inclusion or exclusion criteria or additional monitoring procedures were applied. Deferasirox was administered as recommended in the European Summary of Product Characteristics. Haematological parameters and adverse events (AEs) were collected at two-monthly intervals. Data from 123 chelation-naïve patients with MDS (mean age 70.4 yrs) with median baseline serum ferritin level of 2679 (range 184-16,500) ng/mL, and 44 prechelated patients with MDS (mean age 69.6 yrs) with median baseline serum ferritin level of 2442 (range 521-8565) ng/mL, were assessed. The mean prescribed daily dose of deferasirox at the first visit was 15.7 and 18.7 mg/kg/d, respectively. Treatment with deferasirox produced a significant reduction in median serum ferritin levels in chelation-naïve patients with MDS from 2679 to 2000 ng/mL (P = 0.0002) and a pronounced decrease in prechelated patients with MDS from 2442 to 2077 ng/mL (P = 0.06). The most common drug-related AEs were gastrointestinal, increased serum creatinine levels and rash. These studies demonstrate that deferasirox used in physicians' medical practices is effective in managing iron burden in transfusion-dependent patients with MDS.

Chelation therapy for iron overload: nursing practice implications

Many diseases of the blood are treated with blood transfusion therapy. Chronic transfusions can cause iron overload, and, if untreated, can cause end-organ damage. Chelation therapy provides a way of treating iron overload and minimizing its adverse effects. Nurses need to understand that iron overload is a consequence of chronic blood transfusion, and they need to know what effects it has on end organs and what treatment options are available.

Induction of hypoxia inducible factor (HIF-1α) in rat kidneys by iron chelation with the hydroxypyridinone, CP94

Hypoxia inducible factor (HIF-1α) is a master regulator of tissue adaptive responses to hypoxia whose stability is controlled by an iron containing prolyl hydroxylase domain (PHD) protein. A catalytic redox cycle in the PHD's iron center that results in the formation of a ferryl (Fe(+4)) intermediate has been reported to be responsible for the hydroxylation and subsequent degradation of HIF-1α under normoxia. We show that induction of HIF-1α in rat kidneys can be achieved by iron reduction by the hydroxypyridin-4 one (CP94), an iron chelator administered intraperitoneally in rats. The extent of HIF protein stabilization as well as the expression of HIF target genes, including erythropoietin (EPO), in kidney tissues was comparable to those induced by known inhibitors of the PHD enzyme, such as desferrioxamine (DFO) and cobalt chloride (CoCl(2)). In human kidney cells and in vitro PHD activity assay, we were able to show that the HIF-1α protein can be stabilized by addition of CP94. This appears to inactivate PHD; and thus prevents the hydroxylation of HIF-1α. In conclusion, we have identified the inhibition of iron-binding pocket of PHD as an underlying mechanism of HIF induction in vivo and in vitro by a bidentate hydroxypyridinone.

Regulation of organic nucleic acids and serum biochemistry parameters by dietary chromium picolinate supplementation in swine model

The relationships between chromium and metabolism are sophisticated. Organic nucleic acids and serum biochemistry parameters are affected by dietary chromium levels. The objective of this work was to study the effect of chromium picolinate (CrPic) supplementation on total DNA and RNA contents, the ratio of RNA/DNA in muscle and in pancreatic tissue, the level of insulin receptor (IR) mRNA and some serum biochemistry parameters in a porcine model. Young animals (48) were assigned randomly into three groups of 16 piglets, fed with three different dietary levels of Cr (common basal feedstuff alone or supplemented with CrPic at a dose of 1.61 μg/g or 3.22 μg/g, which corresponds to 0.2 μg/g and 0.4 μg/g Cr). After 80 days, the animals were sacrificed and skeletal muscle and pancreatic tissues were analyzed to detect differences caused by different levels of dietary Cr. The total content of RNA in muscle was increased significantly (P<0.05) in the CrPic supplemented groups. There was no significant difference between groups in the concentrations of total RNA in the pancreas or DNA in the muscle and pancreatic tissues. The RNA/DNA ratio in pancreas showed no significant change but the ratio was increased significantly (P<0.05) in muscle. There was a slight increase of the mRNA level of IR but there was no significant difference between groups. The content of serum cholesterol and insulin were reduced significantly (P<0.05) in the CrPic-supplemented groups and the content of high-density lipoprotein cholesterol (HDLC) was increased significantly (P<0.05) as the CrPic dose increased. There was a slight (non-significant) reduction of the concentrations of serum triglyceride and low-density lipoprotein cholesterol (LDLC) in the CrPic supplementation groups. Supplementary CrPic caused no significant change of muscular mRNA level of IR in healthy animals. An increased content of RNA in muscle, improved cholesterol metabolism and improved insulin sensitivity were found in these CrPic-treated groups in the porcine model.

Absence of teratogenicity of deferasirox treatment during pregnancy in a thalassaemic patient

A 34 year-old female thalassaemia major patient regularly followed in our Thalassaemia Centre was diagnosed at 16 years of age with primary amenorrhea. The endocrine investigations were compatible with hypogonadotropic hypogonadism. Puberty was induced with oral oestrogens and progesterone, followed by transdermal hormone replacement therapy. She had initiated regular blood transfusions at 8 months of age and iron chelation therapy with desferioxamine at the age of 2 years, and in 2006 she was switched to treatment with the oral iron chelator deferasirox (DFX). In November 2009, the patient reported a temporary interruption of transdermal hormone replacement therapy during the previous July and August, and complained of the absence of menstrual flow since then. We suspected a pregnancy that was confirmed by pelvic ultrasound (presence of a fetus of 20 weeks' gestational age) and positive plasma b-hCG levels (14000 mIU/ ml). DFX was immediately discontinued and the patient was managed jointly with an obstetrician expert in haemoglobin disorders. In March 2010 she delivered via caesarean section, at 38 weeks of gestation, a male neonate with a weight of 3.300 Kg with no complications or malformations. The main messages from this patient are that: (i) the hypogonadotropic hypogonadism, secondary to iron overload, may be reversible, (ii) transdermal hormone replacement therapy and regular iron chelation therapy may have had a synergistic action on the activation of hypothalamic-pituitary-gonadal axis, (iii) the deferasirox treatment during pregnancy may be harmless for the fetus at the usually recommended therapeutic doses, (iv) periodic patient education is needed in order to fully explain the aim and the effects of sex steroid hormone replacement therapy given transdermally. The Authors discuss the current knowledge on iron chelation therapy during pregnancy.