Iron Overload Research Articles

Hypoparathyroidism in adults with iron overload diseases (IOD): evidence of a subclinical phenotype.

To explore the prevalence of hypoparathyroidism (HPT), overt and subclinical, in a cohort of adults with Iron Overload Diseases (IOD). Secondary aim was to test the calcium (Ca)-to-phosphorus (P) ratio performance in identifying HPT. Single-center, prospective, case-control study. Sixty-five IOD, 40 with thalassemia major/intermedia (TMI) and 25 with hemochromatosis (HC), and 76 age-matched controls were included. Main outcomes (serum Ca, P, Ca/P ratio, intact parathyroid hormone (PTH), albumin) defined overt and subclinical HPT. Albumin-adjusted Ca was lower (p = 0.004) and P higher (p = 0.002) comparing IOD to controls. Ca/P ratio was lower in IOD than controls (p < 0.001); PTH did not change. P was higher and Ca/P lower comparing TMI to HC and controls (p < 0.001); Ca did not change. A total of 28/65 IOD (43%) had HPT (9.2% overt, 33.8% subclinical) whose prevalence was higher in TMI than HC (p < 0.001). Ca/P ratio <2.32 had sensitivity 71.4% and specificity 83.9% in detecting overt/subclinical HPT. IOD with Ca/P ratio <2.32 (1.78 in SI) had an almost 12-fold increased likelihood to be affected by HPT (OR 12.92 [3.90-42.82]; p < 0.001). Ca/P (p = 0.002) was the only independent risk factor for HPT at multivariate analysis. HPT, especially non-classical subclinical HPT, is common in adult IOD with higher prevalence in TMI than HC. Ca/P ratio <2.32 is accurate to screen for overt/subclinical HPT and should be periodically evaluated in IOD to early detect an unbalanced mineral metabolism, and to monitor a possible evolution from subclinical to overt HPT.

Ferroptosis in Osteoarthritis: Towards Novel Therapeutic Strategy.

Osteoarthritis (OA) is a chronic, degenerative joint disease primarily characterised by damage to the articular cartilage, synovitis and persistent pain, and has become one of the most common diseases worldwide. In OA cartilage, various forms of cell death have been identified, including apoptosis, necroptosis and autophagic cell death. Ever-growing observations indicate that ferroptosis, a newly-discovered iron-dependent form of regulated cell death, is detrimental to OA occurrence and progression. In this review, we first analyse the pathogenetic mechanisms of OA by which iron overload, inflammatory response and mechanical stress contribute to ferroptosis. We then discuss how ferroptosis exacerbates OA progression, focusing on its impact on chondrocyte viability, synoviocyte populations and extracellular matrix integrity. Finally, we highlight several potential therapeutic strategies targeting ferroptosis that could be explored for the treatment of OA.

Expert consensus on the diagnosis and treatment of pyruvate kinase deficiency

Pyruvate kinase deficiency (PKD) is a rare autosomal recessive disorder caused by mutations in the PKLR gene, encoding erythrocyte pyruvate kinase, which affects erythrocyte energy production, and then in turn affects erythrocyte function and longevity. PKD is characterized by chronic hemolytic anemia, and other features include chronic hemolytic complications, such as iron overload, decreased bone mineral density, and cardiopulmonary complications. The treatment of PKD requires individualized approach based on the patient's condition, including red blood cell transfusions, pyruvate kinase activators, and treatment for complications. This consensus focuses on the pathogenesis, clinical characteristics, diagnosis and treatment of PKD, and aims to provide better medical service for clinicians, such as diagnosis, treatment, monitoring, and prevention of complications for PKD patients.

Iron-chelating agent alleviates chronic hydrocephalus in an experimental model of subarachnoid hemorrhage

Background. The iron-chelating agent is being tested in this research to see whether or not it may aid rats with experimental communicating hydrocephalus caused by an intraventricular blood clot. Subarachnoid hemorrhage (SAH) causes chronic post-hemorrhagic hydrocephalus (CPHH) in one-third of patients, and up to 45 % of patients require permanent cerebrospinal fluid diversion during follow-up, with about 50 % shunt failures within a year. Hemoglobin degradation products induce subarachnoid fibrosis and consequent hydrocephalus, with iron as a critical factor. Iron-chelating agents reduce iron overload after SAH. ­Materials and methods. Our study used Wistar rats weighing 250–500 g. The first group (the controls) was without surgery. In the sham group, 0.15 ml of normal saline was administered into the cisterna magna, followed by a second injection 48 hours later. A 0.15 ml blood injection into cisterna magna was followed by a 0.15 ml blood injection 48 hours later, which was performed in the third treatment group, a blood group minus minocycline (BGMM). The fourth double hemorrhagic group (blood group plus minocycline — BGPM) received iron-chelating agent — minocycline. Transcranial ultrasonography was used in all groups, assessing the Levene index (LI) in the rats before and after surgery. CPHH was defined as a ventricular index above the 97th percentile of the pre-intervention LI (1.297). Morphological signs of SAH (blood in subarachnoid space and ventricular wall damage) were evaluated histologically. Results. Ninety-seven operations were done in 50 rats with a 15% posthemorrhagic postoperative mortality. Hydrocephalus in the BGMM group occurred in 56 % of rats, according to the ultrasonography, and all had SAH features with ependymal integrity disruption, according to histological investigations. The introduction of minocycline in the BGPM group prevented an increase in LI after autologous blood injection (similar values of preoperative mean LI = 1.079 ± 0.096 and postoperative mean LI = 1.034 ± 0.058). The difference between BGMM and BGPM groups was highly significant, with a mean of 0.179 ± 0.029, t(41) = 6.12, p &lt; 0.00001. Conclusions. Based on the findings, minocycline alleviates ventriculomegaly in rats. The data suggests that iron-chelating agents may be utilized to treat and prevent CPHH. By illustrating vascular disorders, the technology may become more valuable.

Diammonium glycyrrhizinate alleviates iron overload-induced liver injury in mice via regulating the gut-liver axis

BackgroundEvidence indicates a close association between iron overload (IO) and the pathogenesis of chronic liver diseases, highlighting the potential for interventions targeted at IO to impede or decelerate the progression of chronic liver diseases. Diammonium glycyrrhizinate (DG), the medicinal form of glycyrrhizic acid, a principal constituent of licorice, has been clinically employed as a hepatoprotective agent; however, its protective effect against IO-induced liver injury and underlying molecular mechanisms remain elusive. PurposeThe aim of the present study is to investigate the hepatoprotective effect of DG against IO-induced liver injury with a focus on the gut-liver axis. Study design and methodsAnimal models of IO-induced liver injury and DG treatment have been established in vivo. Iron deposition, liver injury, intestinal barrier damage, and liver inflammation were assessed in mice treated with iron dextran or DG. The microbiome composition in feces was analyzed using 16S rRNA full-length sequencing. Bile acids (BAs) profiles in feces were detected by UPLC-Q-TOF-MS technique, and the expression levels of receptors, enzymes or transporters involved in BAs metabolism were also determined. ResultsDG partially reduced the iron deposition and the levels of ferrous ion in the livers of mice with IO, thereby mitigating oxidative damage. DG also improved gut microbiota dysbiosis, repaired intestinal barrier damage, inhibited endotoxin translocation to the liver, and subsequently suppressed TLR4/NF-κB/NLRP3 pathway-mediated liver inflammation caused by IO. Moreover, DG modulated BAs metabolism disorder in IO mice, reducing the accumulation of BAs in the liver. ConclusionDG alleviates IO-induced liver injury in mice by regulating the gut-liver axis. This study provides novel insights into the underlying mechanisms through which DG ameliorates liver injury caused by IO.

Comparative evaluation of the effects of deferiprone and/or resveratrol in alleviating iron overload-induced tongue injury in rats

Iron overload causes excessive iron deposition in extrahepatic organs, including the tongue. This study aims to compare the deferiprone and/or resveratrol treatments for the alleviation of iron overload-induced tongue injury in rats. Rats were divided into 6 groups: control group, iron-overloaded group, recovery group where rats were left to recover from iron overload, deferiprone-treated group, resveratrol-treated group, and combined deferiprone/resveratrol-treated group. Iron was administered for 4 weeks, while all treatment options were given for the subsequent 4 weeks. After 8 weeks, all rats were sacrificed; the serum iron profile was estimated, and the tongues were assessed by histopathological, tumour necrosis factor alpha (TNF-α) immunohistochemical, histomorphometric, and ultrastructural evaluations. Serum iron parameters were significantly increased in iron-overloaded rats and decreased to control levels only in the combined group. The iron-overloaded tongues demonstrated lost lingual papillae, coarse keratohyalin granules, vacuolated epithelial cells, degenerated muscle fibers, and congested blood vessels. Compared to the control rats, this group revealed a significant decrease in the epithelial layer thickness (550.7 vs. 763.4µm), papillae height (441.4 vs. 849.7µm), and myofiber diameter (58.5 vs. 98.6µm), and increased lamina propria thickness (305.1 vs. 176.8µm), fibrosis index (33.4 vs. 8.6%), and TNF-α immunoexpression (1.16 vs. 0.63 optical density). Additionally, the ultrastructure showed hyperkeratinized papillae, wide interpapillary spaces, flat fungiform papillae, and lost gustatory pores. All these parameters were improved in the recovery, deferiprone, and resveratrol groups to different degrees, while the combined deferiprone/resveratrol treatment was the best option.

Shear Wave Elastography in the Assessment of Liver Iron Overload in Children With Beta Thalassemia Major

Abstract Shear wave elastography (SWE) is an ultrasound method that effectively demonstrates liver fibrosis. This prospective study aimed to compare magnetic resonance imaging T2* and SWE results of the liver in children with thalassemia major (TM). Patients with TM who had regular follow-ups were included. SWE was performed first, followed by MRI T2*. In addition, a healthy control group of the same age group, known to have no liver disease, was recruited. For these participants, only SWE was performed, and their results were compared with the SWE parameters of the TM patients. The study included 38 patients and 25 individuals who made up the control group. The groups with mild, moderate, and severe iron overload according to MRI T2* were compared in terms of SWE with parameters, and no statistically significant difference was found. However, when comparing the SWE parameters between the control group and patients, the median, average, and standard values were found to be statistically significantly higher in the patient group (P &lt; 0.001, P &lt; 0.001, P = 0.026). When comparing MRI T2* results, the median, average, and standard values were found to be statistically significantly higher in the patients with normal and mild iron overload (P &lt; 0.001, P &lt; 0.001, P = 0.033). SWE is an effective, more accessible, and easy-to-apply method for demonstrating early changes in the liver in pediatric patients with TM. This study serves as a guide for more comprehensive studies that may investigate the effect of SWE in this patient group.

Ferroptosis: mechanisms and therapeutic targets.

Ferroptosis is a nonapoptotic form of cell death characterized by iron-dependent lipid peroxidation in membrane phospholipids. Since its identification in 2012, extensive research has unveiled its involvement in the pathophysiology of numerous diseases, including cancers, neurodegenerative disorders, organ injuries, infectious diseases, autoimmune conditions, metabolic disorders, and skin diseases. Oxidizable lipids, overload iron, and compromised antioxidant systems are known as critical prerequisites for driving overwhelming lipid peroxidation, ultimately leading to plasma membrane rupture and ferroptotic cell death. However, the precise regulatory networks governing ferroptosis and ferroptosis-targeted therapy in these diseases remain largely undefined, hindering the development of pharmacological agonists and antagonists. In this review, we first elucidate core mechanisms of ferroptosis and summarize its epigenetic modifications (e.g., histone modifications, DNA methylation, noncoding RNAs, and N6-methyladenosine modification) and nonepigenetic modifications (e.g., genetic mutations, transcriptional regulation, and posttranslational modifications). We then discuss the association between ferroptosis and disease pathogenesis and explore therapeutic approaches for targeting ferroptosis. We also introduce potential clinical monitoring strategies for ferroptosis. Finally, we put forward several unresolved issues in which progress is needed to better understand ferroptosis. We hope this review will offer promise for the clinical application of ferroptosis-targeted therapies in the context of human health and disease.

Heavy Metals in Water and Sediments and Their Impact on Water Quality in Andean Micro-watersheds: A Study of the Colorado and Alajua Rivers in the Ambato River Watershed, Tungurahua, Ecuador

The present study aims to characterize the water and sediment quality of the Colorado and Alajua rivers within Ecuador’s Ambato River watershed, with a specific focus on the presence of heavy metals. Measurements were conducted at five sampling points along the upper and lower zones of each river, where both physicochemical and microbiological parameters, as well as concentrations of heavy metals in water and sediments, were analyzed. Most parameters exhibited statistically significant differences, as determined by the analysis of variance (ANOVA), between the values observed in the upper and lower zones of the micro-watersheds. Water quality in the mentioned rivers was assessed using specific water quality indices, WQI, namely the NSF-WQI and Dinius WQI. Additionally, the impact of heavy metal presence in the water and sediments was evaluated using the Heavy Metal Evaluation Index (HEI). While most parameters met the Ecuadorian quality standards for water sources intended for human consumption, concerns emerged regarding elevated levels of total and fecal coliforms along both rivers, which could limit the suitability of these rivers as a water source for human use and consumption. At various sampling points, water quality criteria for the preservation of aquatic life were not met for several heavy metals. For example, the Colorado River exhibited elevated levels of zinc (59-76 μg.L-1), copper (12-47 μg.L-1), lead (1.2-3.9 μg.L-1 ), iron (0.33-0.37 mg.L-1 ), and manganese (0.37-0.47 mg.L-1), while the Alajua River showed excess copper (11 μg.L-1), iron (0.61-0.72 mg.L-1), and manganese (0.62-0.98 mg.L-1). Geological factors likely contribute to the concentration of heavy metals in the upper segments of the rivers, while agricultural runoff may contribute to concentrations in the lower segments. Sediments exhibited higher average values of the Heavy Metal Evaluation Index (HEI) (20.6-26.7) compared to water samples (13.9-15.4), indicating a potential accumulation of heavy metals in the river sediments. Overall, both rivers exhibited contamination levels ranging from regular to moderate, as indicated by the calculated average Water Quality Indices (WQI), with certain areas showing slight contamination or meeting acceptable standards. These results highlight the influence of anthropogenic activities on water quality, emphasizing the necessity of continuous monitoring to assess and control their impact.

Rational synthesis of FeWO4 nanozyme with sonopiezoelectric and co-catalytic activity for colorimetric detection of deferiprone

Colorimetric sensing based on nanozyme has been extensively applied in the field of biosensing. The analysis time and detection sensitivity depend on the activity of nanozyme. At present, the methods of traditional regulating the activity of nanozyme mainly include internal and external regulation. However, it is still a challenge for internal and external stimuli to coordinate the regulation of nanozyme activity. Both piezoelectricity and co-catalysis can expedite the rate limiting step (Fe3+/Fe2+cycle) of the Fenton reaction hence facilitating the peroxidase-like (POD-like) activity of nanozyme. In this study, we synthesized FeWO4 nanorod that possess sonopiezoelectric and co-catalytic properties. The Fe3+/Fe2+ cycle of FeWO4 nanorods can be boosted by the internal Fe, W co-catalytic reaction and the external ultrasound stimuli generated e−. Deferiprone (DFP), a small molecule of iron chelating agent, is used clinically to chelate excess iron in thalassemia patients. It can specifically inhibit the POD-like activity of the iron-based nanozyme due to coordination with Fe. Based on the above principles, we constructed a colorimetric sensing platform based on FeWO4 nanozyme for colorimetric detection of DFP in urine of thalassemia patients. The linear range, limit of detection and recovery of the developed colorimetric sensing method based on FeWO4 nanozyme platform are 0.1–5 μM, 0.05 μM and 97.4 % − 105.4 %, respectively. This work not only promotes the development of the method to regulate the activity of nanozyme, but also provides a simple method for the monitoring of DFP.

Induced electro-Fenton triggers trace iron utilization for simultaneous organic phosphorous degradation and phosphate recovery

Phosphorus recovery from wastewater has the potential to alleviate both phosphorus scarcity and water pollution. Unlike mineral orthophosphate, organic phosphorus (OP) recovery typically requires multiple steps: oxidation to orthophosphate followed by separation. Electro-Fenton can synchronize these steps in a unified reactor. However, conventional anodic-Fenton (AF) that relies on the direct sacrificial Fe anode, often generates excessive iron sludge. This not only undermines the oxidative capacity but also changes the optimal pH conditions. Herein, we addressed these challenges by developing an induced electro-Fenton (I-EF) system that significantly reduces iron sludge by 94.0 %. The degradation of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC, 5.0 mg P/L) in I-EF reached 76.7 % in 60 min, which is much higher than that (46.0 %) in the conventional AF system. Following PBTC degradation to form PO43-, the I-EF system achieved 88 % PO43- recovery through adsorption onto iron hydroxides. The exceptional performance in simultaneous PBTC degradation and recovery can be attributed to multiple functions of minimal iron utilization in the I-EF system. First, trace iron release can prevent quenching of hydroxyl radicals (·OH) by excessive Fe2+. Second, the absence of strong iron hydrolysis can maintain a stable pH condition (3.0–3.2) for Fenton reaction and avoid PBTC removal through direct coagulation process. The feasibility of I-EF was also successfully demonstrated for other OP forms containing C-P and C-O-P bonds. The degradation efficiency of various OPs was closely related to their bond energy and complexation capacity with iron hydroxides. This study makes use of the I-EF system to innovatively accomplish the degradation of organic phosphorous and simultaneous phosphate recovery.

Thalassemia in Pakistan: Addressing a Genetic Health Crisis

Thalassemia, a genetic disorder usually caused by the defective genes. These genes are responsible for production of hemoglobin, a protein necessary for the transfer of oxygen in body through blood. Prevalence of thalassemia in Pakistan is concerning to a significant level. Global prevalence of this disease has affected millions of people and their lifestyles. Moreover, the disease leads to the burden on the diseased person’s family and the medical resources of the country, causing an alarming concern. The main issue of high prevalence of this disorder in Pakistan is associated with high percentage of cousin marriages. This cultural practice between the close relatives increases the chances of inheriting mutated genes into next generations. Each year more than 5000 children in Pakistan are born with disease. The rate of thalassemia is considerably higher in first cousin marriages (76.7%) than in second cousin marriages (23.3%) [1]. Furthermore, the inadequate spread of awareness among people and the lack of preventative measure by people is contributing to the increase in the number of thalassemia cases Thalassemic patients do require blood transfusion in an adequate to survive and live a normal life. Moreover, after transfusion they need financially draining therapies like iron chelation that is being required to manage the overload of iron in blood. The limited medical resources and poor infrastructure of hospitals and clinics in the rural areas can lead to the increase of complications then reducing the problems come with this disease. This kind of public healthcare system can affect the diseased individuals to level to develop life threatening problems such as stunted growth, and organ failures etc. To address this problem, a national program stating that genetic screening before marriage is necessary can lead to the reduction in the rate if this disease. Premarital screening for inherited diseases including Thalassemia is being carried out in middle east for last more than a decade. Some countries like Iran have overcome this problem to a great level by taking these kinds of initiatives, which shows that how important is it to detect the disease occurrence through premarital screening and counseling [2]. There should be campaigns for the public awareness highlighting the importance of genetic screening so that the cause of occurrence of this disorder can be decreased. Additionally, medical advancements have provided the hope. Despite being costly and scarce, for certain patients with thalassemia, bone marrow transplants (BMT) have proven to be a curative treatment, success rates for those who satisfy the right criteria, such as younger patients with matched related donors, range approximately between 80 and 95% [3]. Future advances in repairing genetic abnormalities at their origins may be possible thanks to emerging gene-editing technologies like CRISPR. To make these remedies available in Pakistan, however, significant funding for medical infrastructure and research is needed. Despite being avoidable, thalassemia will continue to take lives and put a burden on families and communities unless immediate action is taken. Pakistan can considerably lessen the impact of this genetic health disaster and clear the path for a healthier future by placing a high priority on education, early identification, and cutting-edge treatments.

Re-evaluating the utility of iron indices in hereditary hemochromatosis genotyping: A retrospective study

IntroductionHereditary hemochromatosis (HH), associated with C282Y or H63D mutations in the HFE gene, is the commonest genetic disorder in Canada. The majority of HH cases are attributable to C282Y homozygosity which can precipitate iron overload and organ damage, but with low penetrance. Elevated transferrin saturation (TSat) and ferritin levels are key biochemical indicators of iron overload in C282Y homozygotes. This retrospective study examined TSat and ferritin levels as predictors of C282Y homozygosity in genotyped patients. MethodsThis study included 23,432 individuals from Maritime provinces who underwent HFE genotyping from 2009 to 2022. Those with available biomarkers (TSat, ferritin, ALT) were included in the study sample. C282Y and H63D variants were identified based on HFE genotying. Median values for each biomarker were compared across genotypes and their diagnostic performance in predicting C282Y homozygosity evaluated using ROC analysis. Results1241 individuals (5.3 %) showed C282Y homozygosity, marking the largest North American study cohort. C282Y homozygotes showed significantly higher median TSat and ferritin levels than wildtypes. TSat showed the best diagnostic performance in detecting C282Y homozygosity (AUC = 0.82, 95 % CI: 0.78–0.85), outperforming ferritin (AUC = 0.54, 95 % CI: 0.50–0.58) and ALT (AUC = 0.59, 95 % CI: 0.56–0.63). TSat thresholds of 32 % (females) and 35 % (males) had a 90 % sensitivity for C282Y homozygosity. Using thresholds of TSat ≤46 % and ferritin ≤370 µg/L (females), and TSat ≤49 % and ferritin ≤703 µg/L (males) reduced the need for genotyping by up to 50 % without missing significant biochemical iron overload cases. Implementing this strategy across 23,432 tests could save $1,701,163 and potentially reduce unnecessary downstream management. ConclusionOur study suggests significant efficiency savings by implementing an algorithm to reduce unnecessary HFE genotyping and alleviate unwarranted genetic testing anxiety.

EVALUATION OF THE RELATIONSHIP BETWEEN IRON LOAD, AGE, AND CARDIAC FUNCTION IN CHILDREN AND YOUNG ADULTS WITH THALASSEMIA MAJOR: A PULSED-WAVE DOPPLER AND TISSUE DOPPLER IMAGING STUDY

Objective: To determine the structural and functional cardiac differences in children and young adults with thalassemia major (TM) compared to healthy subjects using pulsed-wave Doppler and tissue Doppler imaging methods and determine the relationship between iron overload and these differences. Materials and Methods: We analyzed the data of pediatric and young adult TM patients (n = 44) aged 4–22 years and an age- and gender-matched control group (n = 40) in our hospital data system between Oct.01.2023 and Oct.01.2024. Height, weight, body mass index (BMI), systolic–diastolic blood pressure measurements, complete blood count, ferritin, cardiac T2* magnetic resonance imaging (MRI) values, and echocardiography results were recorded. In addition to comparisons between the two groups, correlation analysis was performed between ferritin–cardiac T2* MRI results and echocardiographic parameters and age in TM patients. Results: Our study showed growth retardation (low height standard deviation score (SDS), low weight SDS and low BMI SDS), dilatation of the left cavities (high left ventricular internal diameter end diastole (LVIDd)), increased left ventricular muscle mass (high left ventricular mass index (LVMI)), cardiac distinctive diastolic (restrictive pattern: left ventricular (LV) peak early diastolic flow (E)/peak late diastolic flow (A) and E/early diastolic myocardial peak flow (E') high), and subclinical systolic (LV peak systolic flow low and LV Tei index high) dysfunction. In addition, iron load (ferritin and cardiac T2* MRI) was correlated with LVMI, and cardiac diastolic and systolic function indicators. As age increased, ferritin value did not change, but cardiac T2* MRI value decreased and diastolic–systolic parameters worsened. Conclusion: Periodic cardiac T2* MRI and Doppler echocardiography examinations of patients with TM may detect subclinical myocardial dysfunction at an early stage, thus providing a window of opportunity for intervention.

N-3 polyunsaturated fatty acids enhanced efficacy of cytarabine in iron-overloaded NALM-6 cells via apoptotic and oxidative pathways

Despite progress in treating acute lymphoblastic leukemia (ALL), the adverse effects of chemotherapy toxicity and iron overload from transfusions continue to affect patients' quality of life. Polyunsaturated fatty acids (PUFAs) exhibit both antitumor and anti-inflammatory properties in leukemia. This study investigated the influence of n-3 PUFA on the efficacy of cytarabine in cells with iron overload. Iron overload was induced in NALM-6 cells using ferric ammonium citrate (FAC) and quantified through atomic absorption spectroscopy (AAS). The impact of n-3 PUFA on NALM-6 cells' response to cytarabine was evaluated using MTT, lactate dehydrogenase (LDH), apoptosis, and cell cycle assays. Additionally, gene expression analyses were performed on apoptotic, anti-apoptotic, and inflammatory genes, along with oxidative stress markers such as reactive oxygen species (ROS) and malondialdehyde (MDA) levels. The administration of n-3 PUFA significantly enhanced the effectiveness of cytarabine in iron-overloaded NALM-6 cells, leading to increased LDH secretion, elevated apoptosis rates, and G1 phase cell cycle arrest. These effects were associated with the upregulation of apoptotic genes such as P53 and caspase-8, the downregulation of the anti-apoptotic gene Bcl2, and a decrease in the inflammatory gene TNF-α. Furthermore, there was a notable increase in ROS and MDA levels. Overall, n-3 PUFA treatment improved cytarabine's efficacy in iron-overloaded NALM-6 cells by activating apoptotic processes and oxidative stress pathways.

GPX4 Promoter Hypermethylation Induced by Ischemia/Reperfusion Injury Regulates Hepatocytic Ferroptosis.

Glutathione peroxidase 4 (GPX4) is a key factor in ferroptosis, which is involved in ischemia-reperfusion injury. However, little is known about its role in hepatic ischemia-reperfusion injury (HIRI). This study aimed to investigate the role of GPX4 methylation in ferroptosis during HIRI. For the in vitro experiments, an oxygen and glucose deprivation cell model was established. For the in vivo experiments, an ischemia-reperfusion model was created by subjecting mice to simulated HIRI. Ferroptosis occurrence, GPX4 promoter methylation, and global methylation levels were then assessed. Ferroptosis was observed in oxygen and glucose deprivation, characterized by a significant decrease in cellular viability (P < 0.05), an increase in lipid peroxidation (P < 0.01), iron overload (P < 0.05), and down-regulation of GPX4 (P < 0.05). This ferroptosis was exacerbated by GPX4 knockdown (P < 0.01) and mitigated by exogenous glutathione (P < 0.01). Similarly, ferroptosis was evident in mice subjected to HIRI, with a down-regulation of GPX4 mRNA and protein expression (all P < 0.01), and an upregulation of acyl-CoA synthetase long-chain family member 4 mRNA and protein (all P < 0.01), as well as prostaglandin-endoperoxide synthase 2 mRNA and protein expression (all P < 0.05). Methylation levels increased, evidenced by upregulation of DNA methylation transferase expression (P < 0.05) and down-regulation of Ten-eleven translocation family demethylases (P < 0.01), along with an upregulation of GPX4 promoter methylation. Ferroptosis may be the primary mode of cell death in hepatocytes following ischemia-reperfusion injury. The methylation of the GPX4 promoter and elevated levels of global hepatic methylation are involved in the regulation of ferroptosis.

Broadening horizons: the multifaceted role of ferroptosis in breast cancer

Breast cancer poses a serious threat to women’s health globally. Current radiotherapy and chemotherapy regimens can induce drug-resistance effects in cancer tissues, such as anti-apoptosis, anti-pyroptosis, and anti-necroptosis, leading to poor clinical outcomes in the treatment of breast cancer. Ferroptosis is a novel programmed cell death modality characterized by iron overload, excessive generation of reactive oxygen species, and membrane lipid peroxidation. The occurrence of ferroptosis results from the imbalance between intracellular peroxidation mechanisms (executive system) and antioxidant mechanisms (defensive system), specifically involving iron metabolism pathways, amino acid metabolism pathways, and lipid metabolism pathways. In recent years, it has been found that ferroptosis is associated with the progression of various diseases, including tumors, hypertension, diabetes, and Alzheimer’s disease. Studies have confirmed that triggering ferroptosis in breast cancer cells can significantly inhibit cancer cell proliferation and invasion, and improve cancer cell sensitivity to radiotherapy and chemotherapy, making induction of ferroptosis a potential strategy for the treatment of breast cancer. This paper reviews the development of the concept of ferroptosis, the mechanisms of ferroptosis (including signaling pathways such as GSH-GPX4, FSP1-CoQ1, DHODH-CoQ10, and GCH1-BH4) in breast cancer disease, the latest research progress, and summarizes the research on ferroptosis in breast cancer disease within the framework of metabolism, reactive oxygen biology, and iron biology. The key regulatory factors and mechanisms of ferroptosis in breast cancer disease, as well as important concepts and significant open questions in the field of ferroptosis and related natural compounds, are introduced. It is hoped that future research will make further breakthroughs in the regulatory mechanisms of ferroptosis and the use of ferroptosis in treating breast cancer cells. Meanwhile, natural compounds may also become a new direction for potential drug development targeting ferroptosis in breast cancer treatment. This provides a theoretical basis and opens up a new pathway for research and the development of drugs for the prevention and treatment of breast cancer.

Mechanisms of METTL14-Mediated m6A Modification in Promoting Iron Overload-Induced Lipid Peroxidative Damage in Vascular Endothelial Cells to Aggravate Atherosclerosis.

Atherosclerosis (AS) is a chronic multifactorial disease with damage to vascular endothelial cells (VECs). This study sought to delve into the mechanism of methyltransferase-like 14 (METTL14) in iron overload-induced lipid peroxidative damage in AS. AS mouse model and cell model were established. Levels of METTL14/circRNA coded by the Arhgap12 (circARHGAP12)/Aspartate β-hydroxylase (ASPH) were determined. AS plaque area/lipid deposition/lipid metabolism in AS mice and iron overload in VECs were evaluated. N6-methyladenosine (m6A) level and METTL14 enrichment and human antigen R (HuR) in circARHGAP12 or ASPH were measured. The mRNA stability of circARHGAP12 or ASPH was analyzed. We observed that METTL14 was upregulated in AS mice. METTL14 downregulation reduced plaque area/lipid deposition/iron overload/peroxidative damage in AS mice. In cell models, METTL14 downregulation could VEC injury/iron overload/lipid peroxidative damage. Mechanically, METTL14 increased the stability and expression of circARHGAP12 through m6A modification, further stabilized ASPH mRNA, and promoted ASPH transcription by binding to HuR. Overexpression of circARHGAP12 or inhibition of ASPH averted the protective role of METTL14 downregulation against iron overload-induced peroxidative damage in AS. In conclusion, METTL14-mediated m6A modification upregulated circARHGAP12 and ASPH to aggravate overload-induced lipid peroxidative damage and facilitate AS progression.

Iron and Inflammatory Cytokines Synergistically Induce Colonic Epithelial Cell Ferroptosis in Colitis.

Inflammatory bowel disease (IBD) is an inflammatory disease that occurs to the intestinal tract. Many patients with IBD often develop anemia and often receive oral iron supplementation. Many of them develop non-compliance with oral iron therapy, but the mechanisms are not well understood. We interrogated whether colonic epithelial iron overload impacts cell viability and disease severity. We observed increased expression of iron importers and iron accumulation in mature colonocytes in dextran sulfate sodium (DSS)-induced acute colitis and in humans with active colitis. Administration of hepcidin increased epithelial iron overload and aggravated colonic inflammation in DSS-treated mice and IL10-/- mice. Hepcidin-induced iron accumulation increased colonic epithelial death, which was prevented by treatment with Trolox, a vitamin E analog and a scavenger of lipid peroxides. By using cultured Caco-2 cells, we showed that iron and inflammatory cytokines (TNF-α and IL-1β) induced a synergistic increase in the number of necrotic cells. We then showed that the combined treatment by hepcidin and cytokines increased labile iron content and lipid peroxidation in Caco-2 cells. Moreover, liproxstatin-1, a ferroptosis inhibitor, and deferoxamine, an iron chelator, both abolished the hepcidin/cytokines induced death of Caco-2 cells, suggesting ferroptosis. We further elucidated that inflammatory cytokines promote lipid peroxidation and ferroptosis by inducing NOX1-dependent exhaustion of reduced glutathione (GSH). Collectively, our findings demonstrate that the inflammatory context predisposes colonic epithelial cells to iron overload mediated ferroptosis, exacerbating colonic inflammation.

Mito-TEMPO Ameliorates Sodium Palmitate Induced Ferroptosis in MIN6 Cells through PINK1/Parkin-Mediated Mitophagy

ObjectiveMitochondrial reactive oxygen species (mtROS) could cause damage to pancreatic β-cells, rendering them susceptible to oxidative damage. Hence, investigating the potential of the mitochondriatargeted antioxidant (Mito-TEMPO) to protect pancreatic β-cells from ferroptosis by mitigating lipid peroxidation becomes crucial. MethodsMIN6 cells were cultured in vitro with 100 μmol/L sodium palmitate (SP) to simulate diabetes. FerroOrange was utilized for the detection of Fe2+ fluorescence staining, BODIPY581/591C11 for lipid reactive oxygen species, and MitoSox-Red for mtROS. Alterations in mitophagy levels were assessed through the co-localization of lysosomal and mitochondrial fluorescence. Western blotting was employed to quantify protein levels of Acsl4, GPX4, FSP1, FE, PINK1, Parkin, TOMM20, P62, and LC3. Subsequently, interventions were implemented using Mito-TEMPO and Carbonyl cyanide 3-chlorophenylhydrazone (CCCP) to observe changes in ferroptosis and mitophagy within MIN6 cells. ResultsWe found that SP induced a dose-dependent increase in Fe2+ and lipid ROS in MIN6 cells while decreasing the expression levels of GPX4 and FSP1 proteins. Through bioinformatics analysis, it has been uncovered that mitophagy assumes a crucial role within the ferroptosis pathway associated with diabetes. Additionally, SP decreased the expression of mitophagy-related proteins PINK1 and Parkin, leading to mtROS overproduction. Conversely, Mito-TEMPO effectively eliminated mtROS while activating the mitophagy pathways involving PINK1 and Parkin, thereby reducing the occurrence of ferroptosis in MIN6 cells. CCCP also demonstrated efficacy in reducing ferroptosis in MIN6 cells. ConclusionIn summary, Mito-TEMPO proved effective in attenuating mtROS production and initiating mitophagy pathways mediated by PINK1 and Parkin in MIN6 cells. Consequently, this decreased iron overload and lipid peroxidation, ultimately safeguarding the cells from ferroptosis.