Iron toxicity and chelation therapy

Dual-channel fluorescent sensor for rapid Cu2+ and Fe3+ detection: Enhanced sensitivity and selectivity with triazole-substituted acridinedione derivative

The AR-2 sensor, derived from a triazole-substituted acridinedione, exhibits distinct responses to Cu2⁺ and Fe³⁺ ions. It shows fluorescence enhancement in the presence of Cu2⁺ ions and a reduction in fluorescence with Fe³⁺ ions. This sensor is distinguished by its high sensitivity, selectivity, rapid response time, reversibility, and broad operating pH range, with shallow detection limits for both ions. Structural and photophysical analyses of AR-2 were conducted using density functional theory (DFT) and various spectroscopic techniques. The binding modes and recognition mechanisms for Cu2⁺ and Fe³⁺ ions were elucidated through multiple experimental approaches. Additionally, AR-2 demonstrated efficacy in the rapid, visual detection of these ions via paper test strips and swab tests. It successfully identified Cu2⁺ and Fe³⁺ ions in real water and food samples, achieving notable recovery rates. The AR-2 sensor also excelled in fluorescence imaging, effectively visualizing iron and copper pools in seed sprouts.

Disproportionality analysis of data from VigiBase and other global product safety databases on toxicity of iron chelating agents

BACKGROUND

Iron chelators; deferasirox, deferiprone, and deferoxamine; used to treat iron toxicities due to excessive ingestions or blood transfusions, may cause serious adverse reactions.

RESEARCH DESIGN AND METHODS

This study investigates pharmacovigilance data to uncover unknown safety information. Disproportionality analysis was conducted using VigiBase, the WHO global database of individual case safety reports, to known safety profile of products and the FDA Adverse Event Reporting System, reviewing over 117.000 iron chelator cases between 2010 and 2020.

RESULTS

Commonly reported adverse events for iron chelators are general disorders and administration site conditions and GI-related disorders. Reporting Odds Ratio was calculated for iron chelator associations to headache (common), blurred vision (rare) and sepsis (serious). Strong association between deferoxamine and blurred vision (ROR: 2.47 in VigiBase and 3.04 in FAERS), deferiprone and sepsis (ROR; 5.95 in VigiBase and 1.24 in FAERS) were identified. However, results showed some inconsistent associations, such as headache and deferiprone, blurred vision and deferasirox association as per FAERS data; sepsis and deferasirox and deferoxamine association as per VigiBase data. Forty-five new potential signals with different associative values were suggested.

CONCLUSION

The study identified strong associations between specific iron chelators and adverse events, though some inconsistencies were observed in the data. These findings, including the 45 new potential signals, suggest areas for further review and validation with additional data.

Association of serum ferritin trends with liver enzyme patterns in β-thalassemia major: A longitudinal correlational study

Background

β-Thalassemia major patients require lifelong blood transfusions, leading to iron overload and liver injury. This study examines the longitudinal association between serum ferritin and liver function over 5 years in pediatric patients.

Methods

This retrospective study included 582 transfusion-dependent thalassemia patients aged 1-18 years. Serum ferritin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and albumin were measured annually. Correlation and linear regression analyses assessed associations between ferritin trajectories and liver enzymes.

Results

Mean ferritin rose from 1820 ± 960 ng/mL at baseline to 4500 ± 1900 ng/mL at year 5, indicating worsening iron overload. AST and ALT levels also steadily climbed over follow-up, whereas albumin declined slightly. Ferritin correlated positively with AST (r = 0.675, P < 0.01) and ALT (r = 0.607, P < 0.01), but not with albumin (r = -0.143, P = 0.153) annually. The regression interaction term showed within-patient ferritin increases over time were independently associated with escalating AST and ALT (P < 0.05), after adjusting for confounders.

Conclusion

Rising ferritin levels predict progressive liver injury in regularly transfused pediatric thalassemia patients. Tighter control of iron overload may help preserve hepatic function.

Heavy Metal Exposure: Molecular Pathways, Clinical Implications, and Protective Strategies

Heavy metals are often found in soil and can contaminate drinking water, posing a serious threat to human health. Molecular pathways and curation therapies for mitigating heavy metal toxicity have been studied for a long time. Recent studies on oxidative stress and aging have shown that the molecular foundation of cellular damage caused by heavy metals, namely, apoptosis, endoplasmic reticulum stress, and mitochondrial stress, share the same pathways as those involved in cellular senescence and aging. In recent aging studies, many types of heavy metal exposures have been used in both cellular and animal aging models. Chelation therapy is a traditional treatment for heavy metal toxicity. However, recently, various antioxidants have been found to be effective in treating heavy metal-induced damage, shifting the research focus to investigating the interplay between antioxidants and heavy metals. In this review, we introduce the molecular basis of heavy metal-induced cellular damage and its relationship with aging, summarize its clinical implications, and discuss antioxidants and other agents with protective effects against heavy metal damage.

Transition Metal Sensing with Nitrogenated Holey Graphene: A First-Principles Investigation

The toxicity of transition metals, including copper(II), manganese(II), iron(II), zinc(II), hexavalent chromium, and cobalt(II), at elevated concentrations presents a significant threat to living organisms. Thus, the development of efficient sensors capable of detecting these metals is of utmost importance. This study explores the utilization of two-dimensional nitrogenated holey graphene (C₂N) nanosheet as a sensor for toxic transition metals. The C₂N nanosheet's periodic shape and standard pore size render it well suited for adsorbing transition metals. The interaction energies between transition metals and C₂N nanosheets were calculated in both gas and solvent phases and were found to primarily result from physisorption, except for manganese and iron which exhibited chemisorption. To assess the interactions, we employed NCI, SAPT0, and QTAIM analyses, as well as FMO and NBO analysis, to examine the electronic properties of the TM@C₂N system. Our results indicated that the adsorption of copper and chromium significantly reduced the HOMO-LUMO energy gap of C₂N and significantly increased its electrical conductivity, confirming the high sensitivity of C₂N towards copper and chromium. The sensitivity test further confirmed the superior sensitivity and selectivity of C₂N towards copper. These findings offer valuable insight into the design and development of sensors for the detection of toxic transition metals.

Discovery-Based Proteomics Identify Skeletal Muscle Mitochondrial Alterations as an Early Metabolic Defect in a Mouse Model of β-Thalassemia

Although metabolic complications are common in thalassemia patients, there is still an unmet need to better understand underlying mechanisms. We used unbiased global proteomics to reveal molecular differences between the th^3/+ mouse model of thalassemia and wild-type control animals focusing on skeletal muscles at 8 weeks of age. Our data point toward a significantly impaired mitochondrial oxidative phosphorylation. Furthermore, we observed a shift from oxidative fibre types toward more glycolytic fibre types in these animals, which was further supported by larger fibre-type cross-sectional areas in the more oxidative type fibres (type I/type IIa/type IIax hybrid). We also observed an increase in capillary density in th^3/+ mice, indicative of a compensatory response. Western blotting for mitochondrial oxidative phosphorylation complex proteins and PCR analysis of mitochondrial genes indicated reduced mitochondrial content in the skeletal muscle but not the hearts of th^3/+ mice. The phenotypic manifestation of these alterations was a small but significant reduction in glucose handling capacity. Overall, this study identified many important alterations in the proteome of th^3/+ mice, amongst which mitochondrial defects leading to skeletal muscle remodelling and metabolic dysfunction were paramount.

Genetic Engineering of Talaromyces marneffei to Enhance Siderophore Production and Preliminary Testing for Medical Application Potential

Siderophores are compounds with low molecular weight with a high affinity and specificity for ferric iron, which is produced by bacteria and fungi. Fungal siderophores have been characterized and their feasibility for clinical applications has been investigated. Fungi may be limited in slow growth and low siderophore production; however, they have advantages of high diversity and affinity. Hence, the purpose of this study was to generate a genetically modified strain in Talaromyces marneffei that enhanced siderophore production and to identify the characteristics of siderophore to guide its medical application. SreA is a transcription factor that negatively controls iron acquisition mechanisms. Therefore, we deleted the sreA gene to enhance the siderophore production and found that the null mutant of sreA (ΔsreA) produced a high amount of extracellular siderophores. The produced siderophore was characterized using HPLC-MS, HPLC-DAD, FTIR, and 1H- and 13C-NMR techniques and identified as a coprogen B. The compound showed a powerful iron-binding activity and could reduce labile iron pool levels in iron-loaded hepatocellular carcinoma (Huh7) cells. In addition, the coprogen B showed no toxicity to the Huh7 cells, demonstrating its potential to serve as an ideal iron chelator. Moreover, it inhibits the growth of Candida albicans and Escherichia coli in a dose-dependent manner. Thus, we have generated the siderophore-enhancing strain of T. marneffei, and the coprogen B isolated from this strain could be useful in the development of a new iron-chelating agent or other medical applications.

Transferrin-mediated increase of labile iron Pool following simulated ischemia causes lipid peroxidation during the early phase of reperfusion

Heart ischemia/reperfusion (I/R) injury is related to iron content. However, the occurrence and mechanism of changes in labile iron pool (LIP) during I/R is debatable. Moreover, the identity of the iron form dominant in LIP during I/R is unclear. Herein, we measured changes of LIP during simulated ischemia (SI) and reperfusion (SR), in which ischemia was simulated in vitro with lactic acidosis and hypoxia. Total LIP did not change in lactic acidosis, whereas LIP, especially Fe³⁺, increased in hypoxia. Under SI, accompanied by hypoxia with acidosis, both Fe²⁺ and Fe³⁺ were significantly increased. Increased total LIP was maintained at 1 h post-SR. However, the Fe²⁺ and Fe³⁺ portion was changed. The increased Fe²⁺ was decreased, and conversely the Fe³⁺ was increased. BODIPY oxidized signal increased and through the time-course these changes correlated with blebbing of cell membrane and SR-induced LDH release. These data suggested lipid peroxidation occurred via Fenton's reaction. The experiments using bafilomycin A1 and zinc protoporphyrin suggested no role of ferritinophagy or heme oxidation in the increase of LIP during SI. The extracellular source, transferrin assessed using serum transferrin bound iron (TBI) saturation showed that the depletion of TBI reduced SR-induced cell damages and additive saturation of TBI accelerated SR-induced lipid peroxidation. Furthermore, Apo-Tf dramatically blocked the increase of LIP and SR-induced damages. In conclusion, Tf-mediated iron induces the increase of LIP during SI, and it causes Fenton reaction-mediated lipid peroxidation during the early phase of SR.

Design, synthesis and biological evaluation of novel dual-targeting fluorescent probes for detection of Fe3+ in the lysosomes of hepatocytes mediated by galactose-morpholine moieties

In this work, novel dual-targeting probes composed of galactose and morpholine were designed and synthesized for monitoring Fe³⁺ levels in the lysosome of hepatocyte. MP-Gal-1, MP-Gal-2 and MP-Gal-3 showed good selectivity and sensitivities toward Fe³⁺ with the detection limits of 9.40 × 10^-8 M, 7.68 × 10^-8 M and 7.10 × 10^-8 M, respectively. 1:2 stoichiometry is the most likely recognition mode between probe and Fe³⁺. Low toxic MP-Gal-1, MP-Gal-2 and MP-Gal-3 exhibited favorable hepatic targeting effect in both cell and tissue levels, which was because the galactose group of probe could be recognized by ASGPR overexpressed on the hepatocytes. The hepatocyte-targeting capacity followed MP-Gal-1 < MP-Gal-2 < MP-Gal-3 trend, which was attributed to the galactose cluster effect. MP-Gal-1, MP-Gal-2 and MP-Gal-3 also displayed good lysosomes-targeting capacities, because the basic morpholine moiety of probes could be easily attracted by the acidic lysosome. Therefore, MP-Gal-1, MP-Gal-2 and MP-Gal-3 have good dual targeting capacities (liver and lysosome) and could be used to detect lysosomal Fe³⁺ in the liver, which is great significant for precise diagnosis and treatment of liver lysosomal iron-related diseases.

Correlation between Serum Fatty Acid Binding Protein 4 (FABP4) Levels and Cardiac Function in Patients with Thalassemia Major

Background

Patients with thalassemia major may suffer from complications due to iron overload. It has been suggested that several adipokines may play a potential role in the development of complications in thalassemia. Fatty acid-binding protein 4 (FABP4) is one of the adipokines, bridging several aspects of metabolic and inflammatory pathways. Little is known about the relationship between this adipokine and cardiac and liver function, especially in patients with thalassemia major.

Aims

This study is aimed at determining serum FABP4 levels in patients with thalassemia major and whether its concentration correlated with serum ferritin levels, as well as cardiac and liver function.

Methods

Thalassemia major outpatients (n = 48) completed laboratory examination, echocardiography, and electrocardiography.

Results

The mean age was 21.9 ± 8.0 years. A negative and weak correlation between serum ferritin and FABP4 was observed (r = −0.291, p < 0.05). In addition, there was moderate and positive correlation between left atrial volume index (LAVI) and FABP4 (r = 0.316, p < 0.05).

Conclusions

Serum FABP4 correlated with serum ferritin and cardiac function in patients with thalassemia major. FABP4 may be a potential clinical biomarker for cardiac dysfunction via metabolic and inflammatory pathways due to iron accumulation and toxicity in patients with thalassemia major.

Modifications on porous absorbable Fe-based scaffolds for bone applications: A review from corrosion and biocompatibility viewpoints

Iron (Fe) and Fe-based scaffolds have become a research frontier in absorbable materials which is inherent to their promising mechanical properties including fatigue strength and ductility. Nevertheless, their slow corrosion rate and low biocompatibility have been their major obstacles to be applied in clinical applications. Over the last decade, various modifications on porous Fe-based scaffolds have been performed to ameliorate both properties encompassing surface coating, microstructural alteration via alloying, and advanced topologically order structural design produced by additive manufacturing (AM) techniques. The recent advent of AM produces topologically ordered porous Fe-based structures with an optimized architecture having controllable pore size and strut thickness, intricate internal design, and larger exposed surface area. This undoubtedly opens up new options for controlling Fe corrosion and its structural strengths. However, the in vitro biocompatibility of the AM porous Fe still needs to be addressed considering its higher corrosion rate due to the larger exposed surface area. This review summarizes the latest progress of the modifications on porous Fe-based scaffolds with a specific focus on their responses on the corrosion behavior and biocompatibility.

Effects of Ejiao peptide-iron chelates on intestinal inflammation and gut microbiota in iron deficiency anemic mice

Iron deficiency is a global nutritional problem that adversely affects the functional regulation of the immune system. In the process of treatment through iron supplementation, the problem of excessive iron intake often occurs, which increases the level of inflammation in the body. Excessive iron can also lead to an increase in intestinal iron-requiring pathogenic bacteria and an imbalance of intestinal flora. In this study, we aim to explore the effect of Ejiao peptide-iron (EPI) chelates on the intestinal flora and inflammation of ICR mice having iron-deficiency anemia (IDA). The mice were given low, medium, and high doses of EPI and FeSO₄ (1.0, 2.0 and 3.0 mg Fe per kg weight, respectively) daily for 4 weeks by intragastric administration. IDA mice showed increased inflammation levels and decreased sIgA secretion, which were restored after intervention with EPI at different doses. Intestinal mucosal ulcers, inflammatory cell infiltration, and oxidative stress in the colon tissue were reduced, and intestinal permeability was improved. Furthermore, 16S rDNA gene sequencing revealed that EPI increased microbial diversity and richness, changing the community structure, therefore, alleviating microbiota dysbiosis caused by IDA (e.g. the proportion of Firmicutes/Bacteroides). Different from the traditional iron supplement FeSO₄, when the pathogenic bacteria (e.g. Helicobacter and Erysipelatoclostridium) increase and the beneficial bacteria (e.g. Bifidobacterium and Blautia) decrease at high doses, EPI shows higher safety at a high dose, thereby maintaining a healthier intestinal homeostasis.

Role of Iron in the Molecular Pathogenesis of Diseases and Therapeutic Opportunities

Iron is an essential mineral that serves as a prosthetic group for a variety of proteins involved in vital cellular processes. The iron economy within humans is highly conserved in that there is no proper iron excretion pathway. Therefore, iron homeostasis is highly evolved to coordinate iron acquisition, storage, transport, and recycling efficiently. A disturbance in this state can result in excess iron burden in which an ensuing iron-mediated generation of reactive oxygen species imparts widespread oxidative damage to proteins, lipids, and DNA. On the contrary, problems in iron deficiency either due to genetic or nutritional causes can lead to a number of iron deficiency disorders. Iron chelation strategies have been in the works since the early 1900s, and they still remain the most viable therapeutic approach to mitigate the toxic side effects of excess iron. Intense investigations on improving the efficacy of chelation strategies while being well tolerated and accepted by patients have been a particular focus for many researchers over the past 30 years. Moreover, recent advances in our understanding on the role of iron in the pathogenesis of different diseases (both in iron overload and iron deficiency conditions) motivate the need to develop new therapeutics. We summarized recent investigations into the role of iron in health and disease conditions, iron chelation, and iron delivery strategies. Information regarding small molecule as well as macromolecular approaches and how they are employed within different disease pathogenesis such as primary and secondary iron overload diseases, cancer, diabetes, neurodegenerative diseases, infections, and in iron deficiency is provided.

Correlation of Serum Ferritin and Liver Iron Concentration with Transient Liver Elastography in Adult Thalassemia Intermedia Patients with Blood Transfusion

INTRODUCTION

Iron overload is a common feature of thalassemia intermedia due to regular blood transfusion and increased gastrointestinal iron absorption. Early detection and adequate iron chelator can decrease morbidity and mortality from iron overload. Liver iron concentration (LIC) by MRI T2* is the best non-invasive way to measure body iron stores. However, this method is expensive and not available nationwide in Indonesia. The aim of this study was to identify liver iron overload and correlation of transferrin saturation, serum ferritin, liver MRI T2* and LIC with transient liver elastography in adult thalassemia intermedia patients.

METHODS

This is a cross-sectional study of 45 patients with thalassemia intermedia with blood transfusion and with and without iron chelator therapy. The study was conducted at Cipto Mangunkusumo Hospital from August through October 2016. We performed measurements of transferrin saturation, serum ferritin level, transient liver elastography and liver MRI T2*. Pearson and Spearman correlation tests were used to evaluate the correlation between transient liver elastography with transferrin saturation, serum ferritin, liver MRI T2*and LIC.

RESULTS AND DISCUSSION

This study showed that 64.4% of study subjects are β-Hb E thalassemia intermedia. Furthermore, 84.4% of study subjects have regular transfusion. Based on liver MRI T2*all subjects suffered from liver iron overload, 48.9% had severe degree. Median value of liver MRI T2* was 1.6 ms. Mean serum ferritin was 2831 ng/mL, with median transferrin saturation of 66%. Mean of LIC corresponding to liver MRI T2* and mean liver stiffness measurement was 15.36±7.37 mg Fe/gr dry weight and 7.7±3.8 kPa, respectively. Liver stiffness correlated with serum ferritin (r=0.651; p=0.000), liver MRI T2* (r=-0.357; p=0.016), and LIC (r=0.433; p=0.003). No correlation was found between liver elastography and transferrin saturation (r=0.204; p=0.178).

CONCLUSION

Serum ferritin, liver MRI T2*and LIC correlated with liver elastography. No correlation was found between transferrin saturation and liver elastography.

Metal cation responsive anionic microgels: behaviour towards biologically relevant divalent and trivalent ions

Anionic poly(vinylcaprolactam-co-itaconicacid-co-dimethylitaconate) microgels were synthesized via dispersion polymerization and their responsiveness towards cations, namely Mg²⁺, Sr²⁺, Cu²⁺ and Fe³⁺, was investigated. The itaconic moieties chelate the metal ions which act as a crosslinker and decrease the electrostatic repulsion within the network, leading to a decrease in the gel size. The responsiveness towards the metal ion concentration has been studied via dynamic light scattering (DLS) and the number of ions bonded within the network has been quantified with ion chromatography. Through the protonation of the carboxylate groups in the gel network, their interaction with the cations is significantly lowered, and the metals are consequently released back in solution. The number of ions released was assessed also via ion chromatography for all four ions, whilst Mg²⁺ was also used as a model ion to display the reversibility of the system. The microgels can bond and release divalent cations over multiple cycles without undergoing any loss of functionality. Moreover, these gels also selectively entrap Fe³⁺ with respect to the remaining divalent cations, opening the possibility of using the proposed gels in the digestive tract as biocompatible chelating agents to fight iron overaccumulation.

Leaves of White Beetroot As a New Source of Antioxidant and Anti-Inflammatory Compounds

The white beetroot cv. Śnieżna Kula is the first betanin-free beetroot registered in the European Union. The aim of this study was to compare the phenolic acids profile and antioxidant capacity of leaves of white (SK) and red (CC) beetroots and red (LC) and white (BL) Swiss chard growing in Poland. LC leaves were the richest source of total phenolics (16.55 mg GAE/g FW) and phenolic acids (1.81 mg/g FW), while the highest content of flavonoids was determined in CC leaves (1.6 mg QE/g FW). The highest antiradical activity was observed for LC, whereas CC extract exhibited the highest chelating power. BL and CC leaf extracts demonstrated high LOX inhibitory potential (EC50 = 53.23 and 56.97 mg FW/mL, respectively). An uncompetitive type of LOX inhibition was obtained for all extracts. SK extracts demonstrated the highest XO inhibitory activity (EC50 = 81.04 mg FW/mL). A noncompetitive type of XO inhibition was obtained in both extracts from red leaves (CC and LC), whereas an uncompetitive mode of inhibition was observed in the case of white leaf (SK and LC) extracts. Thus, it can be assumed that the presence of betanin influences the XO inhibition mechanism.

Highly fluorescent carbon dots derived from Mangifera indica leaves for selective detection of metal ions

In this study, we report an inexpensive, green, and one-pot synthesis method for highly fluorescent carbon quantum dots (CQDs) using mango (Mangifera indica: M. indica) leaves to develop an efficient sensing platform for metal ions. The CQDs synthesized from M. indica leaves via pyrolysis treatment at 300 °C for 3 h were characterized by various spectroscopic and electron microscopy techniques for their structural, morphological, and optical properties. Accordingly, the synthesized CQDs showed an absorption peak at 213 nm to confirm the p-p* transition of the carbon core state, while the CQD particles were spherical with a size less than 10 nm. The prepared CQDs showed excellent fluorescent properties with blue emission spectra (around 525 nm) upon excitation at 435 nm. The synthesized CQDs had the prodigious sensing potential to detect Fe²⁺ ions in water with a limit of detection of 0.62 ppm. Additionally, their sensing capability was tested using a real sample (e.g., Livogen tablet). Moreover, the synthesized CQDs showed substantial stability over a long period (three months). Thus, this study provides an inexpensive and facile method for CQD-based sensing of Fe²⁺ ions with a photoluminescence quenching mechanism.

Additively manufactured functionally graded biodegradable porous iron

Additively manufactured (AM) functionally graded porous metallic biomaterials offer unique opportunities to satisfy the contradictory design requirements of an ideal bone substitute. However, no functionally graded porous structures have ever been 3D-printed from biodegradable metals, even though biodegradability is crucial both for full tissue regeneration and for the prevention of implant-associated infections in the long term. Here, we present the first ever report on AM functionally graded biodegradable porous metallic biomaterials. We made use of a diamond unit cell for the topological design of four different types of porous structures including two functionally graded structures and two reference uniform structures. Specimens were then fabricated from pure iron powder using selective laser melting (SLM), followed by experimental and computational analyses of their permeability, dynamic biodegradation behavior, mechanical properties, and cytocompatibility. It was found that the topological design with functional gradients controlled the fluid flow, mass transport properties and biodegradation behavior of the AM porous iron specimens, as up to 4-fold variations in permeability and up to 3-fold variations in biodegradation rate were observed for the different experimental groups. After 4 weeks of in vitro biodegradation, the AM porous scaffolds lost 5-16% of their weight. This falls into the desired range of biodegradation rates for bone substitution and confirms our hypothesis that topological design could indeed accelerate the biodegradation of otherwise slowly degrading metals, like iron. Even after 4 weeks of biodegradation, the mechanical properties of the specimens (i.e., E = 0.5-2.1 GPa, σ_y = 8-48 MPa) remained within the range of the values reported for trabecular bone. Design-dependent cell viability did not differ from gold standard controls for up to 48 h. This study clearly shows the great potential of AM functionally graded porous iron as a bone substituting material. Moreover, we demonstrate that complex topological design permits the control of mechanical properties, degradation behavior of AM porous metallic biomaterials. STATEMENT OF SIGNIFICANCE: No functionally graded porous structures have ever been 3D-printed from biodegradable metals, even though biodegradability is crucial both for full tissue regeneration and for the prevention of implant-associated infections in the long term. Here, we present the first report on 3D-printed functionally graded biodegradable porous metallic biomaterials. Our results suggest that topological design in general, and functional gradients in particular can be used as an important tool for adjusting the biodegradation behavior of AM porous metallic biomaterials. The biodegradation rate and mass transport properties of AM porous iron can be increased while maintaining the bone-mimicking mechanical properties of these biomaterials. The observations reported here underline the importance of proper topological design in the development of AM porous biodegradable metals.

Heavy metal toxicity: An update of chelating therapeutic strategies

AIM

This review illustrates heavy metals toxicity, currently available therapies and the role and efficacy of chelation therapy for its management.

SUMMARY

Heavy metals are necessary for various biological processes, but they become harmful in excess. Specifically, they induce oxidative stress by generating free radicals and reducing antioxidant levels. Heavy metals also alter the confirmation of protein and DNA and inhibit their function. Chelation therapy is commonly used to treat metals toxicity. Chelation is a chemical process that occurs when interaction between a central metal atom/ion and ligand leads to formation of a complex ring-like structure. The ligand has a donor ion/molecule, which has a lone pair of electrons and may be monodentate to polydentate. Each metal has a different reactivity with a ligand, so a specific chelation agent is required for each metal. Combination therapy with a chelating agent and an antioxidant led to improved outcome.

CONCLUSION

Heavy metal poisoning is a common health problem because of mining, smelting, industrial, agricultural and sewage waste. Heavy metals can be efficiently excreted from the body following treatment with proper chelation agents.

Scaffold Based Search on the Desferithiocin Archetype

Iron overload disorder and diseases where iron mismanagement plays a crucial role require orally available iron chelators with favourable pharmacokinetic and toxicity profile. Desferrithiocin (DFT), a tridentate and orally available iron chelator has a favourable pharmacokinetic profile but its use has been clinically restricted due to its nephrotoxic potential. The chemical architecture of the DFT has been naturally well optimized for better iron chelation and iron clearance from human biological system. Equally they are also responsible for its toxicity. Hence, subsequent research has been devoted to develop a non-nephrotoxic analogue of DFT without losing its iron clearance ability. The review has been designed to classify the compounds reported till date and to discuss the structure activity relationship with reference to modifications attempted at different positions over pyridine and thiazoline ring of DFT. Compounds are clustered under two major classes: (i) Pyridine analogues and (ii) phenyl analogue and further each class has been further subdivided based on the presence or absence and the number of hydroxy functional groups present over pyridine or phenyl ring of the DFT analogues. Finally a summary and few insights into the development of newer analogues are provided.

Iron catalysis of lipid peroxidation in ferroptosis: Regulated enzymatic or random free radical reaction?

Duality of iron as an essential cofactor of many enzymatic metabolic processes and as a catalyst of poorly controlled redox-cycling reactions defines its possible biological beneficial and hazardous role in the body. In this review, we discuss these two "faces" of iron in a newly conceptualized program of regulated cell death, ferroptosis. Ferroptosis is a genetically programmed iron-dependent form of regulated cell death driven by enhanced lipid peroxidation and insufficient capacity of thiol-dependent mechanisms (glutathione peroxidase 4, GPX4) to eliminate hydroperoxy-lipids. We present arguments favoring the enzymatic mechanisms of ferroptotically engaged non-heme iron of 15-lipoxygenases (15-LOX) in complexes with phosphatidylethanolamine binding protein 1 (PEBP1) as a catalyst of highly selective and specific oxidation reactions of arachidonoyl- (AA) and adrenoyl-phosphatidylethanolamines (PE). We discuss possible role of iron chaperons as control mechanisms for guided iron delivery directly to their "protein clients" thus limiting non-enzymatic redox-cycling reactions. We also consider opportunities of loosely-bound iron to contribute to the production of pro-ferroptotic lipid oxidation products. Finally, we propose a two-stage iron-dependent mechanism for iron in ferroptosis by combining its catalytic role in the 15-LOX-driven production of 15-hydroperoxy-AA-PE (HOO-AA-PE) as well as possible involvement of loosely-bound iron in oxidative cleavage of HOO-AA-PE to oxidatively truncated electrophiles capable of attacking nucleophilic targets in yet to be identified proteins leading to cell demise.

Activation of Autophagy, Observed in Liver Tissues From Patients With Wilson Disease and From ATP7B-Deficient Animals, Protects Hepatocytes From Copper-Induced Apoptosis

BACKGROUND & AIMS

Wilson disease (WD) is an inherited disorder of copper metabolism that leads to copper accumulation and toxicity in the liver and brain. It is caused by mutations in the adenosine triphosphatase copper transporting β gene (ATP7B), which encodes a protein that transports copper from hepatocytes into the bile. We studied ATP7B-deficient cells and animals to identify strategies to decrease copper toxicity in patients with WD.

METHODS

We used RNA-seq to compare gene expression patterns between wild-type and ATP7B-knockout HepG2 cells exposed to copper. We collected blood and liver tissues from Atp7b^-/- and Atp7b^+/- (control) rats (LPP) and mice; some mice were given 5 daily injections of an autophagy inhibitor (spautin-1) or vehicle. We obtained liver biopsies from 2 patients with WD in Italy and liver tissues from patients without WD (control). Liver tissues were analyzed by immunohistochemistry, immunofluorescence, cell viability, apoptosis assays, and electron and confocal microscopy. Proteins were knocked down in cell lines using small interfering RNAs. Levels of copper were measured in cell lysates, blood samples, liver homogenates, and subcellular fractions by spectroscopy.

RESULTS

After exposure to copper, ATP7B-knockout cells had significant increases in the expression of 103 genes that regulate autophagy (including MAP1LC3A, known as LC3) compared with wild-type cells. Electron and confocal microscopy visualized more autophagic structures in the cytoplasm of ATP7B-knockout cells than wild-type cells after copper exposure. Hepatocytes in liver tissues from patients with WD and from Atp7b^-/- mice and rats (but not controls) had multiple autophagosomes. In ATP7B-knockout cells, mammalian target of rapamycin (mTOR) had decreased activity and was dissociated from lysosomes; this resulted in translocation of the mTOR substrate transcription factor EB to the nucleus and activation of autophagy-related genes. In wild-type HepG2 cells (but not ATP7B-knockout cells), exposure to copper and amino acids induced recruitment of mTOR to lysosomes. Pharmacologic inhibitors of autophagy or knockdown of autophagy proteins ATG7 and ATG13 induced and accelerated the death of ATP7B-knockout HepG2 cells compared with wild-type cells. Autophagy protected ATP7B-knockout cells from copper-induced death.

CONCLUSION

ATP7B-deficient hepatocytes, such as in those in patients with WD, activate autophagy in response to copper overload to prevent copper-induced apoptosis. Agents designed to activate this autophagic pathway might decrease copper toxicity in patients with WD.

Reductive Mobilization of Iron from Intact Ferritin: Mechanisms and Physiological Implication

Ferritins are highly conserved supramolecular protein nanostructures composed of two different subunit types, H (heavy) and L (light). The two subunits co-assemble into a 24-subunit heteropolymer, with tissue specific distributions, to form shell-like protein structures within which thousands of iron atoms are stored as a soluble inorganic ferric iron core. In-vitro (or in cell free systems), the mechanisms of iron(II) oxidation and formation of the mineral core have been extensively investigated, although it is still unclear how iron is loaded into the protein in-vivo. In contrast, there is a wide spread belief that the major pathway of iron mobilization from ferritin involves a lysosomal proteolytic degradation of ferritin, and the dissolution of the iron mineral core. However, it is still unclear whether other auxiliary iron mobilization mechanisms, involving physiological reducing agents and/or cellular reductases, contribute to the release of iron from ferritin. In vitro iron mobilization from ferritin can be achieved using different reducing agents, capable of easily reducing the ferritin iron core, to produce soluble ferrous ions that are subsequently chelated by strong iron(II)-chelating agents. Here, we review our current understanding of iron mobilization from ferritin by various reducing agents, and report on recent results from our laboratory, in support of a mechanism that involves a one-electron transfer through the protein shell to the iron mineral core. The physiological significance of the iron reductive mobilization from ferritin by the non-enzymatic FMN/NAD(P)H system is also discussed.

The effect of iron chelation therapy on overall survival in sickle cell disease and β-thalassemia: A systematic review

Red blood cell transfusions have become standard of care for the prevention of life-threatening anemia in patients with β-thalassemia and sickle cell disease (SCD). However, frequent transfusions can lead to accumulation of iron that can result in liver cirrhosis, diabetes mellitus, arthritis, arrhythmias, cardiomyopathy, heart failure, and hypogonadotropic hypogonadism. Iron chelation therapy has been shown to reduce serum ferritin levels and liver iron content, but limitations of trial design have prevented any demonstration of improved survival. The objective of this systematic review was to investigate the impact of iron chelation therapy on overall and event-free survival in patients with β-thalassemia and SCD. Eighteen articles discussing survival in β-thalassemia and 3 in SCD were identified. Overall iron chelation therapy resulted in better overall survival, especially if it is instituted early and compliance is maintained. Comparative studies did not show any significant differences between available iron chelation agents, although there is evidence that deferiprone is better tolerated than deferoxamine and that compliance is more readily maintained with the newer oral drugs, deferiprone and deferasirox. Iron chelation therapy, particularly the second-generation oral agents, appears to be associated with improved overall and event-free survival in transfusion-dependent patients with β-thalassemia and patients with SCD.

Biosorption of heavy metals by obligate halophilic fungi

The presence of heavy metals in the environment poses a serious threat to human health. Remediation of this problem using microorganisms has been widely researched to find a sustainable solution. Obligate halophilic fungi comprising Aspergillus flavus, Aspergillus gracilis, Aspergillus penicillioides (sp. 1), Aspergillus penicillioides (sp. 2), Aspergillus restrictus and Sterigmatomyces halophilus were used for the biosorption of cadmium, copper, ferrous, manganese, lead and zinc. The metals were supplemented as salts in potato dextrose broth for the growth of obligate halophilic fungi and incubated for 14 days. The supernatant and biomass were obtained by the acid digestion method. The biosorption was screened by atomic absorption spectroscopy. All tested fungi showed moderate to high adsorption of heavy metals, amongst which A. flavus and S. halophilus showed the best average adsorption of all heavy metals studied, with an average of 86 and 83%, respectively. On average, Fe and Zn are best removed from the liquid media of obligate halophilic fungi, with an average of 85 and 84%, respectively. This pioneering study of biosorption by obligate halophilic fungi using inexpensive media in stagnant conditions provides a cost-effective environmental solution for the removal of heavy metals.

Evaluation of antioxidant potentials of different solvent-fractions of Dialium indium (African Black velvet tamarind) fruit pulp - in vitro

Plant phytonutrients have been harnessed for their various curative properties both in vitro and in vivo. In this study African black velvet tamarind (ABVT) fruit pulp was evaluated for it antioxidant potentials using chloroform and hexane fractions through different antioxidant parameters. In the results; total phenolic contents quantified in mg GAE/dried sample in chloroform and hexane extracts were; 14.57 ±5.85 and 9.78 ±4.61, total flavonoid contents in chloroform and hexane extracts as; 48.58 ±0.00 and 27.35 ±0.00 while the FRAP (µg AAE.g-1 dried sample) was lower in chloroform (298.10 ±0.00) than hexane extracts (1029.81 ±0.00). More also, ability of varied concentrations of the extracts (with their IC50) to cause inhibition against Fe2+-induced MDA that was determined by TBARS in rat's brain and liver tissue homogenates, Fe2+-chelating ability and other antioxidant assays, showed an appreciable significant (p <0.05) difference. The various antioxidant properties showed by ABVT has indicated that, if the pulp is incorporated in diet, it could serve as an alternative in managing various ROS-induced degenerative ailments as it has been clearly demonstrated in the protection of brain and liver homogenates from Fe2+-induced oxidative stress. 

Deferasirox limits cartilage damage following haemarthrosis in haemophilic mice

Joint bleeds in haemophilia result in iron-mediated synovitis and cartilage damage. It was evaluated whether deferasirox, an iron chelator, was able to limit the development of haemophilic synovitis and cartilage damage. Haemophilic mice were randomly assigned to oral treatment with deferasirox (30 mg/kg) or its vehicle (control) (30 mg/kg). Eight weeks after start of treatment, haemarthrosis was induced. After another five weeks of treatment, blood-induced synovitis and cartilage damage were determined. Treatment with deferasirox resulted in a statistically significant (p< 0.01) decrease in plasma ferritin levels as compared to the control group (823 ng/ml ± 56 and 1220 ng/ml ±114, respectively). Signs of haemophilic synovitis, as assessed by the Valentino score [range 0 (normal) – 10 (most affected)], were not different (p=0.52) when comparing the control group with the deferasirox group. However, deferasirox treatment resulted in a statistically significant (p< 0.01) reduction in cartilage damage, as assessed by the loss in Safranin O staining [range 0 (normal) – 6 (most affected)], when comparing the deferasirox group with the control group: score 2 (65.4 % vs 4.2 %), score 3 (26.9 % vs 4.2 %), score 4 (7.7 % vs 20.8 %), score 5 (0 % vs 54.2 %), and score 6 (0 % vs 16.7 %). Treatment with deferasirox limits cartilage damage following the induction of a haemarthrosis in haemophilic mice. This study demonstrates the role of iron in blood-induced cartilage damage. Moreover, these data indicate that iron chelation may be a potential prevention option to limit the development of haemophilic arthropathy.

The Impact of Transfusion and Chelation on Oxidative Stress in Immigrant Syrian Children with β-Thalassemia

Iron overload in β-thalassemia major and intermedia patients leads to oxidative stress and causes to formation of lipid hydroperoxides. Thiobarbituric acid reactive substances (TBARS) are a well established method for screening and monitoring of lipid peroxidation. We aimed to investigate serum TBARS and its relationship with biochemical and hematologic parameters of Turkish and immigrant Syrian β-thalassemia children reflecting the effects of this socioeconomic condition on follow up of these patients. Lipid peroxidation products (TBARS) of Turkish (TR) (n = 62, from the cities of Gaziantep and Sivas, Turkey) and Syrian (SYR) (n = 34, from Gaziantep, Turkey) β-thalassemia patients aged 2-17 years and 58 healthy subjects aged 2-16 years were studied. Liver and renal function tests, serum ferritin levels, white blood cell, absolute neutrophil and platelet counts, hemoglobin (Hb) levels of the patients were analyzed. Serum TBARS concentrations were found to be elevated in β-thalassemia patients compared to healthy subjects (mean: 12.47 ± 8.53 vs. 9.78 ± 7.09, p = 0.045). In SYR patients mean pretransfusional Hb level (7.26.2.04 vs. 8.49 ± 1.01, p = 0.002) was lower and ferritin levels (5983.56 ± 5065.56 vs. 3234.60 ± 2237.82, p = 0.001), liver enzymes (ALT: 77.82 ± 76.48 vs. 42.13 ± 51.50, p = 0.005) were higher when compared to TR group. Positive correlation between TBARS and ferritin levels (p = 0.029, r = 0.231) and liver enzymes (for ALT p < 0.001, r = 0.373) was observed. β-thalassemia patients are under more oxidative stress than healthy subjects. Liver is one of the major organs which are mainly affected by oxidative stress. War and migration might have caused inappropriate transfusion conditions and insufficient chelation therapy in the SYR group.

Neuroprotective effect of deferoxamine on N-methyl-d-aspartate-induced excitotoxicity in RGC-5 cells

Many N-methyl-d-aspartate (NMDA) receptor antagonists have been used to treat neurodegenerative diseases induced by glutamate excitotoxicity in clinics. However, the universality of the glutamic acid neurotransmitter system makes the glutamic acid receptor blockers inefficient and unsafe. Thus, regulating the downstream signaling pathway in the excitotoxicity of glutamic acid may be a more effective and safer way to antagonize the glutamic acid receptor. In this study, we investigated the effect of deferoxamine (DFO), an iron chelator, on the NMDA-induced excitotoxicity. RGC-5 cells were cultured and identified in vitro, and the NMDA-induced injury was assessed. Then the MTT assay was used to estimate the cell survival and JC-1 staining was performed to detect changes in mitochondrial membrane potential. Immunofluorescent staining and western blot analysis were used to analyze the expressions of respiratory chain proteins. It was found that DFO increased the survival rate of RGC-5 cells and that this effect was positively correlated with the concentration of DFO and the treatment time. The mitochondrial membrane potential and the expression levels of succinate dehydrogenase subunit A and cytochrome c oxidase subunit IV were also increased after DFO treatment, while NMDA reduced their expression levels. These data demonstrate that DFO has significant neuroprotective activity against NMDA-induced excitotoxicity in RGC-5 cells.

Lethal Gastric Mucosal Necrosis due to Administration of Oral Ferrous Bisglycinate Chelate to Suckling Piglets

The oral application of a newly developed ferrous bisglycinate paste for suckling piglets at a dose of 180 mg/kg body weight led to increased death rates in 10% (n = 10) of Swiss test pig breeding farms (n = 100). Necropsy examination of suckling piglets (n = 12), selected randomly from the test farms with increased death rates, demonstrated severe gastric mucosal ulceration and necrosis. Due to the presence of crystalline iron surface coating within the gastric lesions, the iron was considered as the toxic principle and cause of death. To demonstrate the direct toxicity of ferrous bisglycinate, the paste was administered experimentally to a litter of suckling piglets (n = 11). Different time points (24, 48 and 72 h post partum) and doses (180 mg/kg and 360 mg/kg) were investigated. The manufacturer's recommended dose of 180 mg/kg corresponded to approximately 36 mg Fe/kg and to 6.4 % of the acute lethal dose₅₀ of oral iron in rats. In all piglets the lesions were reproduced and most severe at the earliest time point (24 h post partum) and with the highest applied dose (360 mg/kg). The lesions were in accordance with those described from oral iron intoxication in man, suggesting pigs as an ideal animal model for oral iron toxicity studies.

Nonabsorbable Iron Binding Polymers Prevent Dietary Iron Absorption for the Treatment of Iron Overload

Chronic iron overload is a serious condition that develops as a consequence of long-term accumulation of iron, eventually overwhelming iron storage systems and causing oxidative stress and subsequent organ damage. Current pharmaceuticals used to treat iron overload typically suffer from toxicities leading to relatively high rates of adverse events. To address this need, we designed a new class of nonabsorbable iron binding polymers (IBPs) that bind and sequester iron within the gastrointestinal (GI) tract. IBPs were synthesized by cross-linking polyallylamine containing various amounts of conjugated 2,3-dihydroxybenzoic acid (DHBA). In vitro studies indicated that IBPs possessed high affinity, substantial binding capacity, and excellent selectivity toward iron. Moreover, in vivo studies demonstrated that IBPs showed no signs of side effects in mice and increased fecal iron excretion when compared to a similar dose of cross-linked polyallylamine. IBPs are a novel, nonabsorbed oral therapeutic agent that may ultimately prevent iron absorption as a safe alternative to iron chelation therapies for patients with hemochromatosis or other iron overload diseases.

The Effects of Nutrition, Exercise, and a Praying Program on Reducing Iron Overload in Patients With Beta-Thalassemia Major: A Randomized Clinical Trial

BACKGROUND

Excessive iron accumulation in the visceral organs creates problems for patients with beta-thalassemia major. Despite chelation therapy, mortality rate from the complications of this disease is still quite high.

OBJECTIVES

This study aimed to investigate the effectiveness of nutrition, exercise, and a praying program at reducing iron overload in patients with beta-thalassemia major.

PATIENTS AND METHODS

This randomized clinical trial assessed the effect of the designed care program on iron overload. The study was conducted in 38 patients with beta-thalassemia major who ranged in age from 15 - 35 years and had been referred to the largest center for thalassemic patients in Shiraz. The patients were randomly assigned to an intervention (n = 18) and a control (n = 20) group. Blood samples were collected from the participants before and two months after the intervention. Then, the data were statistically analyzed using chi-square, Fisher's exact test, Mann-Whitney U-test, Wilcoxon, independent samples t-test, and paired samples t-test.

RESULTS

The results showed that the mean level of serum ferritin significantly decreased in the intervention group two months after beginning the intervention. Also, the mean level of serum iron decreased in the intervention group, but the difference was not statistically significant.

CONCLUSIONS

The planned educational program could be used to reduce iron overload and ultimately improve the patients' health status.

Assessment of Antioxidant Activity and Neuroprotective Capacity on PC12 Cell Line of Frankenia thymifolia and Related Phenolic LC-MS/MS Identification

This work aimed to investigate the richness of a Tunisian xerohalophyte Frankenia thymifolia aerial and root parts on phenolics and to evaluate the antioxidant and neuroprotective properties of this medicinal species. After fractionation using increasing and different solvent polarities, results displayed five fractions, where ethyl acetate (EtOAc) shoot and root fractions possess considerable total phenolic contents (221 and 308 mg of GAE/g of E, resp.) related to their important antioxidant activities such as ORAC (918 and 713 mg of TE/g of E), DPPH (282 and 821 mg of TE/g), and ABTS (778 and 1320 mg of TE/g) tests. Then, the identification of the main compounds by HPLC-DAD-ESI-MS and neuroprotective property of the most active fraction EtOAc were assessed. A total of 14 molecules were identified, which have been described for the first time in F. thymifolia. The major compounds identified were pinoresinol and kaempferol glycoside in aerial parts and gallic acid and ellagitannin in roots. Neuroprotective capacity against β-amyloid (Aβ) peptide induced toxicity in PC12 cells of EtOAc fraction showed a significant protective activity at lower concentration (25 and 50 µM). The relevant antioxidant and neuroprotective activities of F. thymifolia EtOAc fraction corroborated their chemical compositions.

Long-Term Sodium Ferulate Supplementation Scavenges Oxygen Radicals and Reverses Liver Damage Induced by Iron Overloading

Ferulic acid is a polyphenolic compound contained in various types of fruits and wheat bran. As a salt of the active ingredient, sodium ferulate (SF) has potent free radical scavenging activity and can effectively scavenge ROS. In this study, we examined the effect of SF on iron-overloaded mice in comparison to a standard antioxidant, taurine (TAU). We determined the protective role of SF against liver injury by examining liver-to-body ratio (%), transaminase and hepatocyte apoptosis in rats supplied with 10% dextrose intraperitoneal injection. In addition, antioxidative enzymes activities, ROS formation, mitochondrial swelling, and mitochondrial membrane potential (MMP) were all evaluated to clarify the mechanism of protective effect of SF associated with oxidative stress. After 15 weeks of SF treatment, we found a significant reduction in liver-to-body weight radio and elevation in both transaminase and hepatocyte apoptosis associated with iron-injected to levels comparable to those achieved with TAU. Both SF and TAU significantly attenuated the impaired liver function associated with iron-overloaded in mice, whereas neither showed any significant effect on the iron uptake. Furthermore, treatment with either SF or TAU in iron-overloaded mice attenuated oxidative stress, associated with elevated oxidant enzymes activities, decreased ROS production, prevented mitochondrial swelling and dissipation of MMP and then inhibited hepatic apoptosis. Taken together, the current study shows that, SF alleviated oxidative stress and liver damage associated with iron-overload conditions compared to the standard ROS scavenger (TAU), and potentially could encourage higher consumption and utilization as healthy and sustainable ingredients by the food and drink.

Mode of oral iron administration and the amount of iron habitually consumed do not affect iron absorption, systemic iron utilisation or zinc absorption in iron-sufficient infants: a randomised trial

Different metabolic pathways of supplemental and fortification Fe, or inhibition of Zn absorption by Fe, may explain adverse effects of supplemental Fe in Fe-sufficient infants. We determined whether the mode of oral Fe administration or the amount habitually consumed affects Fe absorption and systemic Fe utilisation in infants, and assessed the effects of these interventions on Zn absorption, Fe and Zn status, and growth. Fe-sufficient 6-month-old infants (n 72) were randomly assigned to receive 6·6 mg Fe/d from a high-Fe formula, 1·3 mg Fe/d from a low-Fe formula or 6·6 mg Fe/d from Fe drops and a formula with no added Fe for 45 d. Fractional Fe absorption, Fe utilisation and fractional Zn absorption were measured with oral (57Fe and 67Zn) and intravenous (58Fe and 70Zn) isotopes. Fe and Zn status, infection and growth were measured. At 45 d, Hb was 6·3 g/l higher in the high-Fe formula group compared with the Fe drops group, whereas serum ferritin was 34 and 35 % higher, respectively, and serum transferrin 0·1 g/l lower in the high-Fe formula and Fe drops groups compared with the low-Fe formula group (all P<0·05). No intervention effects were observed on Fe absorption, Fe utilisation, Zn absorption, other Fe status indices, plasma Zn or growth. We concluded that neither supplemental or fortification Fe nor the amount of Fe habitually consumed altered Fe absorption, Fe utilisation, Zn absorption, Zn status or growth in Fe-sufficient infants. Consumption of low-Fe formula as the only source of Fe was insufficient to maintain Fe stores.

The effect of ferrous-chelating hairtail peptides on iron deficiency and intestinal flora in rats

BACKGROUND

Chelating agents, such as small peptides, can decrease free iron content and increase iron bioavailability. They may have promising therapeutic potential and may prevent the pro-oxidant effects of low molecular weight iron. Hairtail is a species of fish that is rich in easily digestible proteins. We extended this strategy for iron delivery by using an enzymatic hydrolysate of hairtail as the chelating agent and found that the ferrous-chelating hairtail peptides have anti-anaemic activity in Sprague-Dawley rats with anaemia.

RESULTS

The anti-anaemic activity of ferrous-chelating hairtail peptides prepared by enzymatic hydrolysis of the hairtail and ferrous chelation was studied in rat models of iron deficiency anaemia. After the end of the 35 d experiment, we noted significant differences in haemoglobin, mean corpuscular volume, haemoglobin distribution width, and ferritin concentrations between those animals supplemented with ferrous-chelating hairtail peptides and FeSO4 and healthy animals. There were no negative side effects on the animals' growth or behaviour. There was no obvious inflammation in the intestinal mucosa lamina propria and no unbalance of intestinal flora.

CONCLUSION

The novel ferrous-chelating hairtail peptides may be a suitable fortificant for improving iron-deficiency status. Our findings demonstrated that this multi-tracer technique has many applications in nutritional research. © 2015 Society of Chemical Industry.

Deferasirox therapy is associated with reduced mortality risk in a medicare population with myelodysplastic syndromes

AIMS

Iron overload adversely affects patients with myelodysplastic syndromes (MDS), but benefits of iron chelation therapy have not been clearly demonstrated. We examined the association between deferasirox (DFX) therapy and mortality in transfusion-receiving Medicare patients.

PATIENTS & METHODS

MDS patients from 2005 to 2008 were identified using ICD-9 codes from 100% Medicare claims. Patients receiving ≥20 blood units were observed until death or end of study. Marginal structural models were used for estimation.

RESULTS

3926 patients (10.1% used DFX) were observed for a mean of 48.8 weeks. Each incremental week of DFX was associated with a significant reduction in mortality risk (hazard ratio [HR]: 0.989; 95% CI: 0.983-0.996; p = 0.001).

CONCLUSION

DFX therapy is associated with a reduced mortality risk among older MDS patients who received a minimum transfusion threshold.

Mangiferin: a promising anticancer bioactive

Of late, several biologically active antioxidants from natural products have been investigated by the researchers in order to combat the root cause of carcinogenesis, in other words, oxidative stress. Mangiferin, a therapeutically active C-glucosylated xanthone, is extracted from pulp, peel, seed, bark and leaf of Mangifera indica. These polyphenols of mangiferin exhibit antioxidant properties and tend to decrease the oxygen-free radicals, thereby reducing the DNA damage. Indeed, its capability to modulate several key inflammatory pathways undoubtedly helps in stalling the progression of carcinogenesis. The current review article emphasizes an updated account on the patents published on the chemopreventive action of mangiferin, apoptosis induction made on various cancer cells, along with proposed antioxidative activities and patent mapping of other important therapeutic properties. Considering it as promising polyphenol, this paper would also summarize the diverse molecular targets of mangiferin.