Iron Regulation Research Articles

Fe (II)/Fe (III) regulated adaptive biofilm responses and microbial metabolic mechanisms for enhanced cycloalkane biodegradation

Oxidation of organic contaminants by iron-cycling microorganisms is an effective remediation strategy for contaminated environments. However, studies on the removal of cycloalkane using this method have been limited, and little is known about how microbes adapt to iron concentrations and how the latter stimulates contaminant degradation. Here, we investigated the biodegradation of cyclohexane (CyH) in three sequencing batch bioreactors (SBRs) with different iron concentrations (SBRs are named: Low 2.5 μM, Suit 7.5 μM, High 75 μM). The Suit reactor showed a more efficient CyH removal performance (average 98.61 ± 0.62 %) than the Low reactor (average 55.75 ± 3.38 %), which was associated with more extracellular polymeric substances (EPS) release and improved biofilm structure. The High reactor exhibited a gradual adaptation process due to the apparent accumulation of reactive oxygen species (ROS) under iron stress, with an average removal efficiency of (86.83 ± 18.81 %). However, the High reactor had a higher microbial activity (1.08-fold increase in ATPase activity) and electron transport system activity (1.18-fold increase) to facilitate direct electron transfer in the presence of insoluble iron compared to the Suit one, largely due to the dominant genus Novosphingobium. Metagenomics and metatranscriptomics analyses revealed lactone (a key intermediate) formation as a potential degradation pathway across three SBRs in our study under iron regulation. Notably, there were differences in the key functional genes expressed under different iron concentrations: genes related to anti-oxidative stress and iron-driven pathways, biofilm regulation-related pathways, and encoding protein complexes III and IV were found in the High, Suit, and Low reactors, respectively. This study enhances understanding of microbiota adaptation mechanisms to iron-disturbed conditions and provides a new insight into iron-cycling mediated biofilm formation and inhibition.

Global Distributions of Reactive Iron and Aluminum Influence the Spatial Variation of Soil Organic Carbon.

Organic carbon persistence in soils is predominantly controlled by physical accessibility rather than by its biochemical recalcitrance. Understanding the regulation of soil iron (Fe) and aluminum (Al) (hydr)oxides, playing a dominant role in mineral protection, on soil organic carbon (SOC) would increase the reliable projections of the feedback of terrestrial ecosystems to global warming. Here, we conducted a continental-scale survey in China (341 sites) and a global synthesis (6786 observations) to reveal the global distributions of Fe/Al (hydr)oxides and their effects on SOC storage in terrestrial ecosystems. We generated the first global maps of soil Fe/Al (hydr)oxides with high accuracy (with R2 more than 0.74). The variance decomposition analysis showed that Fe/Al (hydr)oxides explained the most proportion of variance for topsoil (0-30 cm) and subsoil (30-100 cm) SOC. Therefore, soil Fe/Al (hydr)oxides play a stronger role in explaining the spatial variation of SOC than well-studied climate, edaphic, vegetated, and soil depth factors in both topsoil and subsoil. Collectively, the planetary-scale significance of soil Fe/Al (hydr)oxides for SOC highlights that soil Fe/Al (hydr)oxides should be incorporated into Earth System Models to reduce the uncertainty in predicting SOC dynamics.

SS-31 modification alleviates ferroptosis induced by superparamagnetic iron oxide nanoparticles in hypoxia/reoxygenation cardiomyocytes

Superparamagnetic iron oxide nanoparticles (SPION) are widely used in cardiovascular applications. However, their potential to induce ferroptosis in myocardial cells post-ischemia-reperfusion hinders clinical adoption. We investigated the mechanisms behind SPION-induced cytotoxicity in myocardial cells and explored whether co-loading SPION with SS-31 (a kind of mitochondrial-targeted antioxidant peptide) could counteract this toxicity.To create SPION@SS-31, SS-31 was physically adsorbed onto SPION. To study the dose- and time-dependent cytotoxic effects and assess the influence of SS-31 on reducing SPION-induced damage, hypoxia/reoxygenation(H/R) H9C2 cells were treated with either SPION or SPION@SS-31. We examined the relationship between SPION and ferroptosis by measuring mitochondrial ROS, mitochondrial membrane potential (MMP), lipid peroxidation products, ATP, GSH, GPX4, mitochondrial structure, nonheme iron content, cellular iron regulation, and typical ferroptosis markers.The findings showed that SPION induced concentration- and time-dependent toxicity, marked by a significant cell viability loss and an increase in LDH levels. In contrast, SPION@SS-31 produced results comparable to the H/R group, implying that SS-31 can notably reduce cell damage induced by SPION. SPION disrupted cellular iron homeostasis, with FtH and FtMt expression increased and reduced levels of FPN1 and ABCB8, which led to the overload of mitochondrial iron. This iron dysregulation damaged mitochondrial function and integrity, causing ATP depletion, MMP loss, and decreased GPX4 and GSH levels, accompanied by a burst of mitochondrial lipid peroxidation, ultimately resulting in ferroptosis in H/R cardiomyocytes. Notably, SS-31 significantly alleviated SPION-induced ferroptosis by decreasing mitochondrial MDA production and maintaining GSH and GPX4 levels, indicating its possibility to reverse SPION-induced cytotoxicity. The viability of H/R cells and cells treated with SPION and Fer-1 did not differ statistically, whereas cells exposed to SPION along with inhibitors like 3-MA, zVAD, or Nec-1 showed a substantial loss in viability, implying that ferroptosis is the primary mechanism behind SPION-induced myocardial toxicity.SPION triggers mitochondrial lipid peroxidation by causing overload of iron, leading to ferroptosis in H/R H9C2 cells. Mitochondria appear to be the primary target of SPION-induced toxic effects. SS-31 demonstrates potential in inhibiting this ferroptosis by acting as a mitochondria-targeted antioxidant, suggesting that the modification of mitochondria-targeted antioxidant peptides represents an innovative and practical approach to attenuate the myocardial toxicity associated with SPION.

Are1-mediated nitrogen metabolism is associated with iron regulation in the mycoparasite Trichoderma atroviride

Trichoderma atroviride is a mycoparasitic fungus with antagonistic activity against fungal pathogens and is used as a pathogen control agent alternative to synthetic fungicides. Sensing nutrient availability in the environment and adjusting metabolism for optimal growth, development and reproduction is essential for adaptability and is relevant to its mycoparasitic activity. During mycoparasitism, secondary metabolites are produced to weaken the fungal prey and support the attack. Are1-like proteins act as major GATA-type transcription factors in the activation of genes subject to nitrogen catabolite repression. Since the quality and quantity of nitrogen has been proven particularly relevant in remodeling the biosynthesis of secondary metabolites in fungi, we decided to functionally characterize Are1, the ortholog of Aspergillus nidulans AreA, in T. atroviride. We show that the growth of the T. atroviride ∆are1 mutant is impaired in comparison to the wild type on several nitrogen sources. Deletion of are1 enhanced sensitivity to oxidative and cell-wall stressors and altered the mycoparasitic activity. We were able to identify for the first time a link between Are1 and iron homeostasis via a regulatory mechanism that does not appear to be strictly linked to the nitrogen source, but rather to an independent role of the transcription factor.

ATH434, a promising iron-targeting compound for treating iron regulation disorders.

Cytotoxic accumulation of loosely bound mitochondrial Fe2+ is a hallmark of Friedreich's Ataxia (FA), a rare and fatal neuromuscular disorder with limited therapeutic options. There are no clinically approved medications targeting excess Fe2+ associated with FA or the neurological disorders Parkinson's disease and Multiple System Atrophy. Traditional iron-chelating drugs clinically approved for systemic iron overload that target ferritin-stored Fe3+ for urinary excretion demonstrated limited efficacy in FA and exacerbated ataxia. Poor treatment outcomes reflect inadequate binding to excess toxic Fe2+ or exceptionally high affinities (i.e. ≤10-31) for non-pathologic Fe3+ that disrupts intrinsic iron homeostasis. To understand previous treatment failures and identify beneficial factors for Fe2+-targeted therapeutics, we compared traditional Fe3+ chelators deferiprone (DFP) and deferasirox (DFX) with additional iron-binding compounds including ATH434, DMOG, and IOX3. ATH434 and DFX had moderate Fe2+ binding affinities (Kd's of 1-4 µM), similar to endogenous iron chaperones, while the remaining had weaker divalent metal interactions. These compounds had low/moderate affinities for Fe3+(0.46-9.59µM) relative to DFX and DFP. While all compounds coordinated iron using molecular oxygen and/or nitrogen ligands, thermodynamic analyses suggest ATH434 completes Fe2+ coordination using H2O. ATH434 significantly stabilized bound Fe2+ from ligand-induced autooxidation, reducing reactive oxygen species (ROS) production, whereas DFP and DFX promoted production. The comparable affinity of ATH434 for Fe2+ and Fe3+ position it to sequester excess Fe2+ and facilitate drug-to-protein iron metal exchange, mimicking natural endogenous iron binding proteins, at a reduced risk of autooxidation-induced ROS generation or perturbation of cellular iron stores.

Testosterone therapy-induced erythrocytosis: can phlebotomy be justified?

Erythrocytosis, or elevated hematocrit, is a common side effect of testosterone therapy (TTh) in male hypogonadism. Testosterone stimulates erythropoiesis through an initial rise in erythropoietin (EPO), the establishment of a new EPO/hemoglobin 'set point', and a parallel decrease in the master iron regulator protein hepcidin, as well as several other potential mechanisms. Evidence shows an increased thrombotic risk associated with TTh-induced erythrocytosis. Several guidelines by endocrine organizations for the treatment of male hypogonadism recommend against starting TTh in patients presenting with elevated hematocrit at baseline or stopping TTh when its levels cannot be controlled. Besides dose adjustments, therapeutic phlebotomy or venesection is mentioned as a means of reducing hematocrit in these patients. However, evidence supporting the efficacy or safety of therapeutic phlebotomy in lowering hematocrit in TTh-induced erythrocytosis is lacking. In light of this dearth of evidence, the recommendation to lower hematocrit using therapeutic phlebotomy is notable, as phlebotomy lowers tissue oxygen partial pressure (pO2) and eventually depletes iron stores, thereby triggering various biological pathways which might increase thrombotic risk. The potential pros and cons should therefore be carefully weighed against each other, and shared decision-making is recommended for initiating therapeutic phlebotomy as a treatment in patients on TTh who present with increased hematocrit.

Effect of roxadustat in management of anemia and iron regulation in cirrhosis of liver patients

Effect of roxadustat in management of anemia and iron regulation in cirrhosis of liver patients

The Role of Nutrition on Thyroid Function.

Thyroid function is closely linked to nutrition through the diet-gut-thyroid axis. This narrative review highlights the influence of nutritional components and micronutrients on thyroid development and function, as well as on the gut microbiota. Micronutrients such as iodine, selenium, iron, zinc, copper, magnesium, vitamin A, and vitamin B12 influence thyroid hormone synthesis and regulation throughout life. Dietary changes can alter the gut microbiota, leading not just to dysbiosis and micronutrient deficiency but also to changes in thyroid function through immunological regulation, nutrient absorption, and epigenetic changes. Nutritional imbalance can lead to thyroid dysfunction and/or disorders, such as hypothyroidism and hyperthyroidism, and possibly contribute to autoimmune thyroid diseases and thyroid cancer, yet controversial issues. Understanding these relationships is important to rationalize a balanced diet rich in essential micronutrients for maintaining thyroid health and preventing thyroid-related diseases. The synthetic comprehensive overview of current knowledge shows the importance of micronutrients and gut microbiota for thyroid function and uncovers potential gaps that require further investigation.

SNHG1: Redefining the Landscape of Hepatocellular Carcinoma through Long Noncoding RNAs.

Hepatocellular carcinoma (HCC) represents a global health concern, ranking as the sixth most common malignancy worldwide and the third leading cause of cancer-related mortality. Despite advances in research, the diagnosis and prognosis of such malignancy remain challenging. Alpha-fetoprotein, the current serum biomarker used in the management of HCC, has limited sensitivity and specificity, making early detection and effective management more difficult. Thus, new management approaches in diagnosis and prognosis are needed to improve the outcome and survival of HCC patients. SNHG1 is a long noncoding RNA mainly expressed in the cell and cytoplasm of cells and is consistently upregulated in tissues and cell lines of HCC, where it acts as an important regulator of various processes: modulation of p53 activity, sponging of microRNAs with consequent upregulation of their target mRNAs, regulation of fatty acid, iron and glucose metabolism, and interaction with immune cells. The deregulation of these processes results in abnormal cell division, angiogenesis, and apoptosis, thus promoting various aspects of tumorigenesis, including proliferation, invasion, and migration of cells. Clinically, a higher expression of SNHG1 predicts poorer clinical outcomes by significantly correlating with bigger, less differentiated, and more aggressive tumors, more advanced disease stages, and lower overall survival in HCC patients. This article comprehensively summarizes the current understanding of the multifaceted roles of SNHG1 in the pathogenesis of HCC, while also highlighting its clinicopathological correlations, therefore concluding that it has potential as a biomarker in HCC diagnosis and prognosis.

Platelet-Rich Plasma (PRP) Mitigates Kidney Dysfunction in Alloxan-Induced Diabetic Mice via Modulation of Renal Iron Regulatory Genes.

Kidney dysfunction is a prevalent complication of diabetes mellitus, contributing significantly to diabetes-related morbidity and mortality. We aim to explore whether platelet-rich plasma administration can modulate iron regulation mechanism within the kidney, thereby mitigating renal dysfunction associated with diabetes. Albino mice with an average body weight of 20 ± 5g were randomly divided into five groups (N = 50; n = 10): Control Group, PRP Group, diabetic group (DG), treated group A (TA), and treated group B (TB). A single intraperitoneal dose of alloxan (160mg/kg of body weight) was administered to mice in the DG and in both treated groups. Upon confirmation of diabetes, the DG was left untreated, while PRP treatment (0.5ml/kg of body weight) was administered to the TA and TB groups for two and four weeks, respectively. Histological examinations of kidney tissues revealed notable signs of damage in DG, which were subsequently improved upon PRP treatment. Likewise, PRP treatment restored the changes in liver enzymes, oxidative stress biomarkers and serum electrolytes in both treated groups. Furthermore, there was an observed upregulation of iron regulatory genes, such as Renin, Epo, Hepc, Kim1, and Hfe, in the DG, accompanied by a downregulation of Tfr1 and Fpn; however, Dmt1 and Dcytb1 expression remained unaltered. Treatment with PRP restored the expression of iron regulatory genes in both treated groups. This study concluded that PRP treatment effectively restored the renal histochemistry and the expression of renal iron regulatory genes in an alloxan-induced diabetic mice model.

Erythropoietin enhances iron bioavailability in HepG2 cells by downregulating hepcidin through mTOR, C/EBPα and HIF-1α

The regulation of iron (Fe) levels is essential to maintain an adequate supply for erythropoiesis, among other processes, and to avoid possible toxicity. The liver-produced peptide hepcidin is regarded as the main regulator of Fe absorption in enterocytes and release from hepatocytes and macrophages, as it impairs Fe export through ferroportin. The glycoprotein erythropoietin (Epo) drives erythroid progenitor survival and differentiation in the bone marrow, and has been linked to the mobilization of Fe reserves necessary for hemoglobin production. Herein we show that Epo inhibits hepcidin expression directly in the HepG2 hepatic cell line, thus leading to a decrease in intracellular Fe levels. Such inhibition was dependent on the Epo receptor-associated kinase JAK2, as well as on the PI3K/AKT/mTOR pathway, which regulates nutrient homeostasis. Epo was also found to decrease binding of the C/EBP-α transcription factor to the hepcidin promoter, which could be attributed to an increased expression of its inhibitor CHOP. Epo did not only hinder the stimulating effect of C/EBP-α on hepcidin transcription, but also favored hepcidin inhibition by HIF-1α, by increasing is nuclear translocation as well as its protein levels. Moreover, in assays with the inhibitor genistein, this transcription factor was found necessary for Epo-induced hepcidin suppression. Our findings support the involvement of the PI3K/AKT/mTOR pathway in the regulation of Fe levels by Epo, and highlight the contrasting roles of the C/EBP-α and HIF-1α transcription factors as downstream effectors of the cytokine in this process.

Strain variation in the Candida albicans iron limitation response.

Iron acquisition is critical for pathogens to proliferate during invasive infection, and the human fungal pathogen Candida albicans is no exception. The iron regulatory network, established in reference strain SC5314 and derivatives, includes the central player Sef1, a transcription factor that activates iron acquisition genes in response to iron limitation. Here, we explored potential variation in this network among five diverse C. albicans strains through mutant analysis, Nanostring gene expression profiling, and, for two strains, RNA-Seq. Our findings highlight four features that may inform future studies of natural variation and iron acquisition in this species. (i) Conformity: In all strains, major iron acquisition genes are upregulated during iron limitation, and a sef1Δ/Δ mutation impairs that response and growth during iron limitation. (ii) Response variation: Some aspects of the iron limitation response vary among strains, notably the activation of hypha-associated genes. As this gene set is tied to tissue damage and virulence, variation may impact the progression of infection. (iii) Genotype-phenotype variation: The impact of a sef1Δ/Δ mutation on cell wall integrity varies, and for the two strains examined the phenotype correlated with sef1Δ/Δ impact on several cell wall integrity genes. (iv) Phenotype discovery: DNA repair genes were induced modestly by iron limitation in sef1Δ/Δ mutants, with fold changes we would usually ignore. However, the response occurred in both strains tested and was reminiscent of a much stronger response described in Cryptococcus neoformans, a suggestion that it may have biological meaning. In fact, we observed that the iron limitation of a sef1Δ/Δ mutant caused recessive phenotypes to emerge at two heterozygous loci. Overall, our results show that a network that is critical for pathogen proliferation presents variation outside of its core functions.IMPORTANCEA key virulence factor of Candida albicans is the ability to maintain iron homeostasis in the host where iron is scarce. We focused on a central iron regulator, SEF1. We found that iron regulator Sef1 is required for growth, cell wall integrity, and genome integrity during iron limitation. The novel aspect of this work is the characterization of strain variation in a circuit that is required for survival in the host and the connection of iron acquisition to genome integrity in C. albicans.

Targeting ferroptosis: a new therapeutic opportunity for kidney diseases.

Ferroptosis is a form of non-apoptotic regulated cell death (RCD) that depends on iron and is characterized by the accumulation of lipid peroxides to lethal levels. Ferroptosis involves multiple pathways including redox balance, iron regulation, mitochondrial function, and amino acid, lipid, and glycometabolism. Furthermore, various disease-related signaling pathways also play a role in regulating the process of iron oxidation. In recent years, with the emergence of the concept of ferroptosis and the in-depth study of its mechanisms, ferroptosis is closely associated with various biological conditions related to kidney diseases, including kidney organ development, aging, immunity, and cancer. This article reviews the development of the concept of ferroptosis, the mechanisms of ferroptosis (including GSH-GPX4, FSP1-CoQ1, DHODH-CoQ10, GCH1-BH4, and MBOAT1/2 pathways), and the latest research progress on its involvement in kidney diseases. It summarizes research on ferroptosis in kidney diseases within the frameworks of metabolism, reactive oxygen biology, and iron biology. The article introduces key regulatory factors and mechanisms of ferroptosis in kidney diseases, as well as important concepts and major open questions in ferroptosis and related natural compounds. It is hoped that in future research, further breakthroughs can be made in understanding the regulation mechanism of ferroptosis and utilizing ferroptosis to promote treatments for kidney diseases, such as acute kidney injury(AKI), chronic kidney disease (CKD), diabetic nephropathy(DN), and renal cell carcinoma. This paves the way for a new approach to research, prevent, and treat clinical kidney diseases.

Fibrinogen-like 1: A hepatokine linking liver physiology to hematology.

A recent study identified the critical contribution of the hepatokine FGL1 to the regulation of iron metabolism during the recovery from anemia. FGL1 is secreted by hepatocytes in response to hypoxia to sequester BMP ligands and repress the transcription of the iron-regulatory hormone hepcidin. This process ensures the proper supply of iron to the bone marrow for new red blood cell synthesis and the restoration of physiological oxygen levels. FGL1 may therefore contribute to the recovery from common anemias and cause iron overload in chronic anemias with ineffective erythropoiesis, such as ß-thalassemia, dyserythropoietic anemia, and myelodysplastic syndromes. However, FGL1 has also been described as a regulator of hepatocyte proliferation, glucose homeostasis, and insulin signaling, as well as a mediator of liver steatosis and immune evasion. Chronic exposure to elevated levels of FGL1 during anemia may therefore have systemic metabolic effects besides iron regulation and erythropoiesis. Here, we are providing an overview of the proposed functions of FGL1 in physiology and pathophysiology.

Phenotypic, genotypic and proteomic variations between poor and robust colonizing Campylobacter jejuni strains

Campylobacter jejuni is one of the major causes of bacterial gastrointestinal disease in humans worldwide. This foodborne pathogen colonizes the intestinal tracts of chickens, and consumption of chicken and poultry products is identified as a common route of transmission. We analyzed two C. jejuni strains after oral challenge with 105 CFU/ml of C. jejuni per chick; one strain was a robust colonizer (A74/C) and the other a poor colonizer (A74/O). We also found extensive phenotypic differences in growth rate, biofilm production, and in vitro adherence, invasion, intracellular survival, and transcytosis. Strains A74/C and A74/O were genotypically similar with respect to their whole genome alignment, core genome, and ribosomal MLST, MLST, flaA, porA, and PFGE typing. The global proteomes of the two congenic strains were quantitatively analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and 618 and 453 proteins were identified from A74/C and A74/O isolates, respectively. Cluster of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that carbon metabolism and motility proteins were distinctively overexpressed in strain A74/C. The robust colonizer also exhibited a unique proteome profile characterized by significantly increased expression of proteins linked to adhesion, invasion, chemotaxis, energy, protein synthesis, heat shock proteins, iron regulation, two-component regulatory systems, and multidrug efflux pump. Our study underlines phenotypic, genotypic, and proteomic variations of the poor and robust colonizing C. jejuni strains, suggesting that several factors may contribute to mediating the different colonization potentials of the isogenic isolates.

Transcriptional Analysis Reveals the Iron Regulation Network of the Pathogenic Yeast Metschnikowia bicuspidata in Response to Iron Stress

Metschnikowia bicuspidata, a globally distributed opportunistic pathogenic fungus, poses a significant threat to crustaceans in diverse aquatic ecosystems, causing severe diseases. Iron, recognized as a virulence factor, plays a crucial role in successful infection with M. bicuspidata. Therefore, this study aims to investigate the transcriptome response of M. bicuspidata to low- and high-iron conditions. Overall, 1082 differentially expressed genes (DEGs) (FDR < 0.05, |log2FC ≥ 1.5|) were identified, comprising 977 and 105 DEGs, in response to low- and high-iron conditions, respectively. These genes predominantly participate in altering metabolism, cell membranes, or cellular structure, allowing the organism to adapt to varying iron levels. Iron limitation-induced genes play crucial roles in energy metabolism, transport, and catabolism pathways. Moreover, 27 ortholog genes were associated with iron transport and homeostasis, with 7 of them participating in iron uptake and regulation under low-iron conditions. This study contributes to the comprehension of iron homeostasis in aquatic fungi. It may offer potential therapeutic strategies for managing M. bicuspidata diseases.

Advances in integrating single-cell sequencing data to unravel the mechanism of ferroptosis in cancer.

Ferroptosis, a commonly observed type of programmed cell death caused by abnormal metabolic and biochemical mechanisms, is frequently triggered by cellular stress. The occurrence of ferroptosis is predominantly linked to pathophysiological conditions due to the substantial impact of various metabolic pathways, including fatty acid metabolism and iron regulation, on cellular reactions to lipid peroxidation and ferroptosis. This mode of cell death serves as a fundamental factor in the development of numerous diseases, thereby presenting a range of therapeutic targets. Single-cell sequencing technology provides insights into the cellular and molecular characteristics of individual cells, as opposed to bulk sequencing, which provides data in a more generalized manner. Single-cell sequencing has found extensive application in the field of cancer research. This paper reviews the progress made in ferroptosis-associated cancer research using single-cell sequencing, including ferroptosis-associated pathways, immune checkpoints, biomarkers, and the identification of cell clusters associated with ferroptosis in tumors. In general, the utilization of single-cell sequencing technology has the potential to contribute significantly to the investigation of the mechanistic regulatory pathways linked to ferroptosis. Moreover, it can shed light on the intricate connection between ferroptosis and cancer. This technology holds great promise in advancing tumor-wide diagnosis, targeted therapy, and prognosis prediction.

The Impact of the Combined Effect of Inhalation Anesthetics and Iron Dextran on Rats' Systemic Toxicity.

Disruption of any stage of iron homeostasis, including uptake, utilization, efflux, and storage, can cause progressive damage to peripheral organs. The health hazards associated with occupational exposure to inhalation anesthetics (IA) in combination with chronic iron overload are not well documented. This study aimed to investigate changes in the concentration of essential metals in the peripheral organs of rats after iron overload in combination with IA. The aim was also to determine how iron overload in combination with IA affects tissue metal homeostasis, hepcidin-ferritin levels, and MMP levels according to physiological, functional, and tissue features. According to the obtained results, iron accumulation was most pronounced in the liver (19×), spleen (6.7×), lungs (3.1×), and kidneys (2.5×) compared to control. Iron accumulation is associated with elevated heavy metal levels and impaired essential metal concentrations due to oxidative stress (OS). Notably, the use of IA increases the iron overload toxicity, especially after Isoflurane exposure. The results show that the regulation of iron homeostasis is based on the interaction of hepcidin, ferritin, and other proteins regulated by inflammation, OS, free iron levels, erythropoiesis, and hypoxia. Long-term exposure to IA and iron leads to the development of numerous adaptation mechanisms in response to toxicity, OS, and inflammation. These adaptive mechanisms of iron regulation lead to the inhibition of MMP activity and reduction of oxidative stress, protecting the organism from possible damage.

A Carbamoyl Oxime-Based Highly Specific Fluorescent Chemodosimeter for Monitoring Labile Fe2+ in Food and Living Organisms.

Iron is an essential element in the composition of living organisms and plays a crucial role in a wide range of biological activities. The human body primarily obtains essential iron through the consumption of food. Therefore, it is vital for the health of human body to maintain iron homeostasis. The reducing character of the cellular microenvironment enables Fe2+ to occupy a dominant position within the cell. Hence, there is an urgent need for a simple and sensitive tool that can detect a large amount of Fe2+ in organisms. In this work, a highly specific fluorescent chemodosimeter NPCO ("NP" represents the naphthalimide fluorophore, and "CO" represents the carbamoyl oxime structure) for the detection of Fe2+ with excellent sensitivity (LOD = 82 nM) was constructed by incorporating a novel carbamoyl oxime structure as the recognition group. NPCO can be effectively employed for the detection of Fe2+ in food samples, living cells, and zebrafish. Furthermore, by using soybean sprouts as a model plant, the application of NPCO was expanded to detect Fe2+ in plants. Therefore, NPCO could be used as an excellent assay tool for detecting Fe2+ in organisms and is expected to be an important aid in exploring the mechanism of iron regulation.

The potential significance of hepcidin evaluation in progressive supranuclear palsy.

Hepcidin is a peptide associated with controlling the distribution of iron in tissues. Growing interest is linked with its impact on neurodegenerative diseases, as disruption of the iron regulation may be considered an initiatory element of pathological protein accumulation. The possible impact of hepcidin was not previously sufficiently explored in progressive supranuclear palsy (PSP). Twelve patients with PSP-Richardson's syndrome (PSP-RS), 12 with PSP-Parkinsonism Predominant (PSP-P), and 12 controls were examined using Unified Parkinson's Disease Rating Scale-III part (UPDRS-III) in OFF stage and analyzed in the context of hepcidin levels in the serum. The work revealed increased levels of hepcidin in PSP-RS when compared to PSP-P and controls. Moreover, hepcidin was found to be negatively correlated with UPDRS-III results in PSP-RS, whereas positively in PSP-P. The work may suggest a possible impact of hepcidin in PSP, possibly differing depending on its subtype.