Iron Metabolism Research Articles

Unveiling New Genetic Variants Associated with Age at Onset in Alzheimer's Disease and Frontotemporal Lobar Degeneration Due to C9orf72 Repeat Expansions.

Alzheimer's disease (AD) and Frontotemporal lobar degeneration (FTLD) represent the most common forms of neurodegenerative dementias with a highly phenotypic variability. Herein, we investigated the role of genetic variants related to the immune system and inflammation as genetic modulators in AD and related dementias. In patients with sporadic AD/FTLD (n = 300) and GRN/C9orf72 mutation carriers (n = 80), we performed a targeted sequencing of 50 genes belonging to the immune system and inflammation, selected based on their high expression in brain regions and low tolerance to genetic variation. The linear regression analyses revealed two genetic variants: (i) the rs1049296 in the transferrin (TF) gene, shown to be significantly associated with age at onset in the sporadic AD group, anticipating the disease onset of 4 years for each SNP allele with respect to the wild-type allele, and (ii) the rs7550295 in the calsyntenin-1 (CLSTN1) gene, which was significantly associated with age at onset in the C9orf72 group, delaying the disease onset of 17 years in patients carrying the SNP allele. In conclusion, our data support the role of genetic variants in iron metabolism (TF) and in the modulation of the calcium signalling/axonal anterograde transport of vesicles (CLSTN1) as genetic modulators in AD and FTLD due to C9orf72 expansions.

SCD1 promotes the stemness of gastric cancer stem cells by inhibiting ferroptosis through the SQLE/cholesterol/mTOR signalling pathway

Cancer stem cells (CSCs) play a substantial role in cancer onset and recurrence. Anomalous iron and lipid metabolism have been documented in CSCs, suggesting that ferroptosis, a recently discovered form of regulated cell death characterised by lipid peroxidation, could potentially exert a significant influence on CSCs. However, the precise role of ferroptosis in gastric cancer stem cells (GCSCs) remains unknown. To address this gap, we screened ferroptosis-related genes in GCSCs using The Cancer Genome Atlas and corroborated our findings through quantitative polymerase chain reaction and western blotting. These results indicate that stearoyl-CoA desaturase (SCD1) is a key player in the regulation of ferroptosis in GCSCs. This study provides evidence that SCD1 positively regulates the transcription of squalene epoxidase (SQLE) by eliminating transcriptional inhibition of P53. This mechanism increases the cholesterol content and the elevated cholesterol regulated by SCD1 inhibits ferroptosis via the mTOR signalling pathway. Furthermore, our in vivo studies showed that SCD1 knockdown or regulation of cholesterol intake affects the stemness of GCSCs and their sensitivity to ferroptosis inducers. Thus, targeting the SCD1/squalene epoxidase/cholesterol signalling axis in conjunction with ferroptosis inducers may represent a promising therapeutic approach for the treatment of gastric cancer based on GCSCs.

A global transcriptional activator involved in the iron homeostasis in cyanobacteria.

Cyanobacteria use a series of adaptation strategies and a complicated regulatory network to maintain intracellular iron (Fe) homeostasis. Here, a global activator named IutR has been identified through three-dimensional chromosome organization and transcriptome analysis in a model cyanobacterium Synechocystis sp. PCC 6803. Inactivation of all three homologous IutR-encoding genes resulted in an impaired tolerance of Synechocystis to Fe deficiency and loss of the responses of Fe uptake-related genes to Fe-deplete conditions. Protein-promoter interaction assays confirmed the direct binding of IutR with the promoters of genes related to Fe uptake, and chromatin immunoprecipitation sequencing analysis further revealed that in addition to Fe uptake, IutR could regulate many other physiological processes involved in intracellular Fe homeostasis. These results proved that IutR is an important transcriptional activator, which is essential for cyanobacteria to induce Fe-deficiency response genes. This study provides in-depth insights into the complicated Fe-deficient signaling network and the molecular mechanism of cyanobacteria adaptation to Fe-deficient environments.

Exploring the targetome of IsrR, an iron-regulated sRNA controlling the synthesis of iron-containing proteins in Staphylococcus aureus.

Staphylococcus aureus is a common colonizer of the skin and nares of healthy individuals, but also a major cause of severe human infections. During interaction with the host, pathogenic bacteria must adapt to a variety of adverse conditions including nutrient deprivation. In particular, they encounter severe iron limitation in the mammalian host through iron sequestration by haptoglobin and iron-binding proteins, a phenomenon called "nutritional immunity." In most bacteria, including S. aureus, the ferric uptake regulator (Fur) is the key regulator of iron homeostasis, which primarily acts as a transcriptional repressor of genes encoding iron acquisition systems. Moreover, Fur can control the expression of trans-acting small regulatory RNAs that play an important role in the cellular iron-sparing response involving major changes in cellular metabolism under iron-limiting conditions. In S. aureus, the sRNA IsrR is controlled by Fur, and most of its predicted targets are iron-containing proteins and other proteins related to iron metabolism and iron-dependent pathways. To characterize the IsrR targetome on a genome-wide scale, we combined proteomics-based identification of potential IsrR targets using S. aureus strains either lacking or constitutively expressing IsrR with an in silico target prediction approach, thereby suggesting 21 IsrR targets, of which 19 were negatively affected by IsrR based on the observed protein patterns. These included several Fe-S cluster- and heme-containing proteins, such as TCA cycle enzymes and catalase encoded by katA. IsrR affects multiple metabolic pathways connected to the TCA cycle as well as the oxidative stress response of S. aureus and links the iron limitation response to metabolic remodeling. In contrast to the majority of target mRNAs, the IsrR-katA mRNA interaction is predicted upstream of the ribosome binding site, and further experiments including mRNA half-life measurements demonstrated that IsrR, in addition to inhibiting translation initiation, can downregulate target protein levels by affecting mRNA stability.

PDK4-mediated Nrf2 inactivation contributes to oxidative stress and diabetic kidney injury

Diabetic kidney disease (DKD) is often featured with redox dyshomeostatis. Pyruvate dehydrogenase kinase 4 (PDK4) is the hub for DKD development. However, the mechanism by which PDK4 mediates DKD is poorly understood. The current work aimed to elucidate the relationship between PDK4 and DKD from the perspective of redox manipulation. Oxidative stress was observed in the human proximal tubular cell line (HK-2 cells) treated with a high concentration of glucose and palmitic acid (HGL). The mechanistic study showed that PDK4 could upregulate Kelch-like ECH-associated protein 1 (Keap1) in HGL-treated HK-2 cells through the suppression of autophagy, resulting in the depletion of nuclear factor erythroid 2-related factor 2 (Nrf2), the master regulator of redox homeostasis. At the cellular level, pharmacological inhibition or genetic knockdown of PDK4 could boost Nrf2, followed by the increase of a plethora of antioxidant enzymes and ferroptosis-suppression enzymes. Meanwhile, the inhibition or knockdown of PDK4 remodeled iron metabolism, further mitigating oxidative stress and lipid peroxidation. The same trend was observed in the DKD mice model. The current work highlighted the role of PDK4 in the development of DKD and suggested that PDK4 might be a promising target for the management of DKD.

Protopanaxadiol prevents cisplatin-induced acute kidney injury by regulating ferroptosis.

Acute kidney injury (AKI) caused by cisplatin (CDDP) is a complex, critical illness with no effective or specific treatment. The purpose of the study was to assess the protective effect of protopanaxadiol (PPD) on the kidneys in CDDP-induced AKI models and its possible mechanisms. In vitro, the protection of PPD was assessed in HK-2. KM mice were injected with CDDP to induce AKI models in vivo. The determination of blood urea nitrogen and serum creatinine (SCr) was performed, and pathological changes were examined by histopathological examination. Immunostaining and western blot analyses were used to analyze the expression levels of proteins. PPD can increase the viability of HK-2 cells damaged by CDDP, improve cell morphology, and alleviate the symptoms of AKI in mice. In addition, PPD can down-regulate the protein expression of TRF and up-regulate the protein expression of Ferritin heavy chain, Glutathione peroxidase 4, and ferroptosis suppressor protein 1 reduce the iron content in cells and kidney tissues, and restore the antioxidant defense system. PPD has an inhibitory effect on cisplatin-induced nephrotoxicity, which may be related to the inhibition of ferroptosis by regulating iron metabolism and lipid peroxidation.

Multiple Roles of Apolipoprotein E4 in Oxidative Lipid Metabolism and Ferroptosis During the Pathogenesis of Alzheimer’s Disease

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease worldwide and has a great socio-economic impact. Modified oxidative lipid metabolism and dysregulated iron homeostasis have been implicated in the pathogenesis of this disorder, but the detailed pathophysiological mechanisms still remain unclear. Apolipoprotein E (APOE) is a lipid-binding protein that occurs in large quantities in human blood plasma, and a polymorphism of the APOE gene locus has been identified as risk factors for AD. The human genome involves three major APOE alleles (APOE2, APOE3, APOE4), which encode for three subtly distinct apolipoprotein E isoforms (APOE2, APOE3, APOE4). The canonic function of these apolipoproteins is lipid transport in blood and brain, but APOE4 allele carriers have a much higher risk for AD. In fact, about 60% of clinically diagnosed AD patients carry at least one APOE4 allele in their genomes. Although the APOE4 protein has been implicated in pathophysiological key processes of AD, such as extracellular beta-amyloid (Aβ) aggregation, mitochondrial dysfunction, neuroinflammation, formation of neurofibrillary tangles, modified oxidative lipid metabolism, and ferroptotic cell death, the underlying molecular mechanisms are still not well understood. As for all mammalian cells, iron plays a crucial role in neuronal functions and dysregulation of iron homeostasis has also been implicated in the pathogenesis of AD. Imbalances in iron homeostasis and impairment of the hydroperoxy lipid-reducing capacity induce cellular dysfunction leading to neuronal ferroptosis. In this review, we summarize the current knowledge on APOE4-related oxidative lipid metabolism and the potential role of ferroptosis in the pathogenesis of AD. Pharmacological interference with these processes might offer innovative strategies for therapeutic interventions.

Mechanistic elucidation of ferroptosis and ferritinophagy: implications for advancing our understanding of arthritis.

In recent years, the emerging phenomenon of ferroptosis has garnered significant attention as a distinctive mode of programmed cell death. Distinguished by its reliance on iron and dependence on reactive oxygen species (ROS), ferroptosis has emerged as a subject of extensive investigation. Mechanistically, this intricate process involves perturbations in iron homeostasis, dampening of system Xc-activity, morphological dynamics within mitochondria, and the onset of lipid peroxidation. Additionally, the concomitant phenomenon of ferritinophagy, the autophagic degradation of ferritin, assumes a pivotal role by facilitating the liberation of iron ions from ferritin, thereby advancing the progression of ferroptosis. This discussion thoroughly examines the detailed cell structures and basic processes behind ferroptosis and ferritinophagy. Moreover, it scrutinizes the intricate web of regulators that orchestrate these processes and examines their intricate interplay within the context of joint disorders. Against the backdrop of an annual increase in cases of osteoarthritis, rheumatoid arthritis, and gout, these narrative sheds light on the intriguing crossroads of pathophysiology by dissecting the intricate interrelationships between joint diseases, ferroptosis, and ferritinophagy. The newfound insights contribute fresh perspectives and promising therapeutic avenues, potentially revolutionizing the landscape of joint disease management.

P-704 Distinctive proteomic profiling and pathway analysis of plasma extracellular vesicles provided clues for their regulatory roles in the pathogenesis of polycystic ovarian syndrome

Abstract Study question To elucidate the distinctive proteomic profiling of plasma extracellular vesicles (EVs) and the pathogenic contributions in polycystic ovarian syndrome (PCOS). Summary answer In PCOS, differentially expressed proteins in the circulatory exosomes are associated with the several characteristic signaling pathways related to cardiovascular and metabolism risks. What is known already EVs from various tissues or body fluids have been shown to be involved in the pathogenesis of PCOS and might serve as potential biomarkers for the diagnosis and prognostic prediction. Most of previous studies focus on the miRNAs expression of EVs isolated from blood, endometrium and follicular fluid. However, a comprehensive quantitative protein analysis of circulatory EVs has seldom been conducted in PCOS. Whether and how the proteomic profiling of circulatory EVs is related to the characteristic phenotypic expression is also unclear. Study design, size, duration This is a case-control study conducted at the reproductive endocrinologic department of the tertiary medical center from 2019 to 2022. Blood samples were collected from sixty PCOS and thirty non-PCOS control subjects. Participants/materials, setting, methods Plasma EVs were isolated by sucrose gradient-based ultracentrifugation. Quantitative proteomic analysis was performed by tandem mass tag labeling and liquid chromatography tandem mass spectrometry (TMT) to identify differentially expressed proteins. The functions and pathways of identified proteins were analyzed with Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The correlation between the identified proteins and the clinical, hormonal, and biochemical parameters were also analyzed. Main results and the role of chance Nanoparticle tracking analysis suggested the majority of EVs were 70-190 nm in diameter, which were corresponsive to the size of exosome. Differential expressed protein (DEP) analysis revealed distinctive upregulated proteins in the circulatory exosomes of PCOS patients, includes IGF-1, HIST1H1E, PF4, HBA1, HBB, SNC73, which were enriched in nitric oxide transport and negative regulation of extrinsic apoptotic signaling pathway. Proteins which were downregulated in PCOS patients, including RAA1, RARRES2, CFHR1, LBP, IGFBP3, TPI1, SERPINA5, SNC73, were enriched in lipid transport and complement and coagulation cascades. There is significant correlation between the differentially expressed exosome proteins and several clinical phenotypes, including hypertension, hyperandrogenism and iron metabolism. The enriched pathways and characterized phenotypes have been shown to be closely related to cardiovascular and metabolic aberrations of PCOS, which could provide pathogenic clues for how the circulatory EVs proteins contribute to the disease development and progression. Limitations, reasons for caution PCOS is highly heterogeneous and the case number of our study might not be large enough to differentiate distinctive patterns among different subtypes of PCOS. The enrolled population is limited to reproductive-age Asian patients and might not be generalized to other age or ethnic groups. Wider implications of the findings Our results could be apply to further studies for biomarker identification and mechanistic researches, and to elucidate whether and how the proteomic biology of circulatory EVs is related to the pathogenesis of PCOS. Trial registration number not applicable

Iron Metabolism in Pediatric Living related Liver Transplantation

Abstract Introduction Iron deficiency is a frequent cause of anemia in liver transplant recipients, especially children. Rejection and infection are incriminated causes for occurrence of anemia after liver transplantation (LR). Aim of the Work We aimed to assess iron homeostasis in children who have undergone living related LT (LRLT) and its correlation with occurrence of rejection and infection. Patients and Methods The study was conducted on 35 children who have undergone LRLT. The patient characteristics, frequency of infection and rejection episodes, laboratory investigations including complete blood picture (CBC) and Iron profile (total iron binding capacity (TIBC),serum iron and ferritin) during the patient follow up visits were reported. Results Males were 68.58% of the studied patients and females were 31.42%. Their ages ranged from 1.3-15 years at time of LT with mean (SD) of 7.18 (3.8)years. The mean (SD) duration since LT was 4.83 (4.2) years. The commonest indication to LT was highgamma-glutamyl transferase (GGT) cholestasis (34.7%) followed by biliary atresia (21.7 %). Thirteen percent of patients had low hemoglobin (Hb) of whom 4.3% had normocytic normochromic anemia and 8.7% had microcytic hypochromic anemia. Serum iron was normal in 79.6% of patients and low in 20.4%, and ferritin was normal in 58.7% of patients and low in 41.3% while TIBC was normal in 82.6% of patients and low in 17.4%. Only serum iron showed significant negative correlation with white blood cells (WBCs) (P < 0.05). The iron parameters levels were not different in patients with no rejection or only one attack of rejection and the patients with multiple rejection episodes (P > 0.05). Conclusion Anemia is a reported complication after pediatric LT. Further studies are needed to assess the long term effect of post-LT anemia on patient outcome after LT.

Synergistic mechanisms of denitrification in FeS2-based constructed wetlands: Effects of organic carbon availability under day-night alterations

In constructed wetlands (CWs), carbon source availability profoundly affected microbial metabolic activities engaged in both iron cycle and nitrogen metabolism. However, research gaps existed in understanding the biotransformation of nitrogen and iron in response to fluctuations in organic carbon content under day-night alterations. Results demonstrated increased removal efficiency of NO3−-N (95.7 %) and NH4+-N (75.70 %) under light conditions, attributed to increased total organic carbon (TOC). This enhancement promoted the relative abundance of bacteria involved in nitrogen and iron processes, establishing a more stable microbial network. Elevated TOC content also upregulated genes for iron metabolism and glycolysis, facilitating denitrification. Spearman correlation analysis supported the synergistic mechanisms between FeS2-based autotrophic denitrification and TOC-mediated heterotrophic denitrification under light conditions. The significant impact of carbon sources on microbial activities underscores the critical role of organic carbon availability in enhancing nitrogen removal efficiency, providing valuable insights for optimizing FeS2-based CWs design and operation strategies.

Insights into the role of glycerophospholipids on the iron export function of SLC40A1 and the molecular mechanisms of ferroportin disease.

SLC40A1 is the sole iron export protein reported in mammals. In humans, its dysfunction is responsible for ferroportin disease, an inborn error of iron metabolism transmitted as an autosomal dominant trait and observed in different ethnic groups. As a member of the major facilitator superfamily, SLC40A1 requires a series of conformational changes to enable iron translocation across the plasma membrane. The influence of lipids on protein stability and its conformational changes has been little investigated to date. Here, we combine molecular dynamics simulations of SLC40A1 embedded in membrane bilayers with experimental alanine scanning mutagenesis to analyze the specific role of glycerophospholipids. We identify four basic residues (Lys90, Arg365, Lys366, and Arg371) that are located at the membrane-cytosol interface and consistently interact with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) molecules. These residues surround a network of salt bridges and hydrogens bonds that play a critical role in stabilizing SLC40A1 in its basal outward-facing conformation. More deeply embedded in the plasma membrane, we identify Arg179 as a charged amino acid residue also tightly interacting with lipid polar heads. This results in a local deformation of the lipid bilayer. Interestingly, Arg179 is adjacent to Arg178, which forms a functionally important salt-bridge with Asp473 and is a recurrently associated with ferroportin disease when mutated to glutamine. We demonstrate that the two p.Arg178Gln and p.Arg179Thr missense variants have similar functional behaviors. These observations provide insights into the role of phospholipids in the formation/disruption of the SLC40A1 inner gate, and give a better understanding of the diversity of molecular mechanisms of ferroportin disease.

Golgi protein ACBD3 downregulation sensitizes cells to ferroptosis.

Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, is emerging as a promising target in cancer therapy. It is regulated by a network of molecules and pathways that modulate lipid metabolism, iron homeostasis and redox balance, and related processes. However, there are still numerous regulatory molecules intricately involved in ferroptosis that remain to be identified. Here, we indicated that suppression of Golgi protein acyl-coenzyme A binding domain A containing 3 (ACBD3) increased the sensitivity of Henrieta Lacks and PANC1 cells to ferroptosis. ACBD3 knockdown increases labile iron levels by promoting ferritinophagy. This increase in free iron, coupled with reduced levels of glutathione peroxidase 4 due to ACBD3 knockdown, leads to the accumulation of reactive oxygen species and lipid peroxides. Moreover, ACBD3 knockdown also results in elevated levels of polyunsaturated fatty acid-containing glycerophospholipids through mechanisms that remain to be elucidated. Furthermore, inhibition of ferrtinophagy in ACBD3 downregulated cells by knocking down the nuclear receptor co-activator 4 or Bafilomycin A1 treatment impeded ferroptosis. Collectively, our findings highlight the pivotal role of ACBD3 in governing cellular resistance to ferroptosis and suggest that pharmacological manipulation of ACBD3 levels is a promising strategy for cancer therapy.

Social defeat stress impairs systemic iron metabolism by activating the hepcidin-ferroportin axis.

Chronic psychological stress has been reported to decrease circulating iron concentrations and impair hematopoiesis. However, the underlying mechanisms remain unclear. This study aimed to investigate the effects of psychological stress on biological iron metabolism by using the social defeat stress (SDS) model, a widely used model of depression. Compared with control mice, mice subjected to SDS (SDS mice) had lower social interaction (SI) behavior. The SDS mice also showed impaired hematopoiesis, as evidenced by reduced circulating red blood cell counts, elevated reticulocyte counts, and decreased plasma iron levels. In the SDS mice, the iron contents in the bone marrow decreased, whereas those in the spleen increased, suggesting dysregulation in systemic iron metabolism. The concentrations of plasma hepcidin, an important regulator of systemic iron homeostasis, increased in the SDS mice. Meanwhile, the concentrations of ferroportin, an iron transport protein negatively regulated by hepcidin, were lower in the spleen and duodenum of the SDS mice than in those of the control mice. Treatment with dalteparin, a hepcidin inhibitor, prevented the decrease in plasma iron levels in the SDS mice. The gene expression and enzyme activity of furin, which converts the precursor hepcidin to active hepcidin, were high and positively correlated with plasma hepcidin concentration. Thus, furin activation might be responsible for the increased plasma hepcidin concentration. This study is the first to show that psychological stress disrupts systemic iron homeostasis by activating the hepcidin-ferroportin axis. Consideration of psychological stressors might be beneficial in the treatment of diseases with iron-refractory anemia.

Peroxiredoxin 6 Protects Pulmonary Epithelial Cells From Cigarette-related Ferroptosis in Chronic Obstructive Pulmonary Disease.

Peroxiredoxin 6 (PRDX6) has a protective effect on pulmonary epithelial cells against cigarette smoke (CS)-induced ferroptosis. This study investigates the role of PRDX6 in the development of chronic obstructive pulmonary disease (COPD) and its possibility as a target. We observed that PRDX6 was downregulated in lung tissues of COPD patients and in CS-stimulated cells. The degradation of PRDX6 could be through the lysosomal pathway. PRDX6 deficiency exacerbated pulmonary inflammation and mucus hypersecretion in vivo. Overexpression of PRDX6 in Beas-2B cells ameliorated CS-induced cell death and inflammation, suggesting its protective role against CS-induced damage. Furthermore, PRDX6 deficiency promoted ferroptosis by adding the content of iron and reactive oxygen species, while iron chelation with deferoxamine mitigated CS-induced ferroptosis, cell death, and inflammatory infiltration both in vitro and in vivo. The critical role of PRDX6 in regulating ferroptosis suggests that targeting PRDX6 or iron metabolism may represent a promising strategy for COPD treatment.

Whole-exome sequencing identifies protein-coding variants associated with brain iron in 29,828 individuals

Iron plays a fundamental role in multiple brain disorders. However, the genetic underpinnings of brain iron and its implications for these disorders are still lacking. Here, we conduct an exome-wide association analysis of brain iron, measured by quantitative susceptibility mapping technique, across 26 brain regions among 26,789 UK Biobank participants. We find 36 genes linked to brain iron, with 29 not being previously reported, and 16 of them can be replicated in an independent dataset with 3,039 subjects. Many of these genes are involved in iron transport and homeostasis, such as FTH1 and MLX. Several genes, while not previously connected to brain iron, are associated with iron-related brain disorders like Parkinson’s (STAB1, KCNA10), Alzheimer’s (SHANK1), and depression (GFAP). Mendelian randomization analysis reveals six causal relationships from regional brain iron to brain disorders, such as from the hippocampus to depression and from the substantia nigra to Parkinson’s. These insights advance our understanding of the genetic architecture of brain iron and offer potential therapeutic targets for brain disorders.

Iron capture through CD71 drives perinatal and tumor-associated Treg expansion.

Besides suppressing immune responses, regulatory T cells (Tregs) maintain tissue homeostasis and control systemic metabolism. Whether iron is involved in Treg-mediated tolerance is completely unknown. Here, we showed that the transferrin receptor CD71 was upregulated on activated Tregs infiltrating human liver cancer. Mice with a Treg-restricted CD71 deficiency spontaneously developed a scurfy-like disease, caused by impaired perinatal Treg expansion. CD71-null Tregs displayed decreased proliferation and tissue-Treg signature loss. In perinatal life, CD71 deficiency in Tregs triggered hepatic iron overload response, characterized by increased hepcidin transcription and iron accumulation in macrophages. Lower bacterial diversity, and reduction of beneficial species, were detected in the fecal microbiota of CD71 conditional knockout neonates. Our findings indicate that CD71-mediated iron absorption is required for Treg perinatal expansion and is related to systemic iron homeostasis and bacterial gut colonization. Therefore, we hypothesize that Tregs establish nutritional tolerance through competition for iron during bacterial colonization after birth.

Exploring the relationship between anastasis and mitochondrial ROS-mediated ferroptosis in metastatic chemoresistant cancers: a call for investigation.

Ferroptosis induces significant changes in mitochondrial morphology, including membrane condensation, volume reduction, cristae alteration, and outer membrane rupture, affecting mitochondrial function and cellular fate. Recent reports have described the intrinsic cellular iron metabolism and its intricate connection to ferroptosis, a significant kind of cell death characterized by iron dependence and oxidative stress regulation. Furthermore, updated molecular insights have elucidated the significance of mitochondria in ferroptosis and its implications in various cancers. In the context of cancer therapy, understanding the dual role of anastasis and ferroptosis in chemoresistance is crucial. Targeting the molecular pathways involved in anastasis may enhance the efficacy of ferroptosis inducers, providing a synergistic approach to overcome chemoresistance. Research into how DNA damage response (DDR) proteins, metabolic changes, and redox states interact during anastasis and ferroptosis can offer new insights into designing combinatorial therapeutic regimens against several cancers associated with stemness. These treatments could potentially inhibit anastasis while simultaneously inducing ferroptosis, thereby reducing the likelihood of cancer cells evading death and developing resistance to chemotherapy. The objective of this study is to explore the intricate interplaybetween anastasis, ferroptosis, EMT and chemoresistance, and immunotherapeutics to better understand their collective impact on cancer therapy outcomes. We searched public research databases including google scholar, PubMed, relemed, and the national library of medicine related to this topic. In this review, we discussed the interplay between the tricarboxylic acid cycle and glycolysis implicated in modulating ferroptosis, adding complexity to its regulatory mechanisms. Additionally, the regulatory role of reactive oxygen species (ROS) and the electron transport chain (ETC) in ferroptosis has garnered significant attention. Lipid metabolism, particularly involving GPX4 and System Xc- plays a significant role in both the progression of ferroptosis and cancer. There is a need to investigate the intricate interplay between anastasis, ferroptosis, and chemoresistance to better understand cancer therapy clinical outcomes. Integrating anastasis, and ferroptosis into strategies targeting chemoresistance and exploring its potential synergy with immunotherapy represent promising avenues for advancing chemoresistant cancer treatment. Understanding the intricate interplay among mitochondria, anastasis, ROS, and ferroptosis is vital in oncology, potentially revolutionizing personalized cancer treatment and drug development.

Iron metabolism in doxorubicin-induced cardiotoxicity: From mechanisms to therapies

Doxorubicin (DOX) is an anti-tumor agent for chemotherapy, but its use is often hindered by the severe and life-threatening side effect of cardiovascular toxicity. In recent years, studies have focused on dysregulated iron metabolism and ferroptosis, a unique type of cell death induced by iron overload, as key players driving the development of DOX-induced cardiotoxicity (DIC). Recent advances have demonstrated that DOX disturbs normal cellular iron metabolism, resulting in excessive iron accumulation and ferroptosis in cardiomyocytes. This review will explore how dysregulated iron homeostasis and ferroptosis drive the progression of DIC. We will also discuss the current approaches to target iron metabolism and ferroptosis to mitigate DIC. Besides, we will discuss the limitations and challenges for clinical translation for these therapeutic regimens.

Investigating the Hepcidin Gene Polymorphisms in COVID-19-Associated Mucormycosis Susceptibility: A Clinical-Laboratory Study.

Following the coronavirus disease 2019 outbreak (COVID-19), it became a worrisome health burden worldwide. COVID-19-associated mucormycosis emergence, characterized by dysregulated inflammation and iron metabolism, exacerbated the prognosis of affected patients. Given the significance of hepcidin in regulating inflammation and iron metabolism, this study investigated the significance of hepcidin single nucleotide polymorphisms (SNP) in COVID-19-associated mucormycosis development, along with the association between the clinical and laboratory factors and COVID-19-associated mucormycosis. From September 2021 to November 2021, COVID-19 patients with and without mucormycosis were enrolled in this cross-sectional study. Their medical records and laboratory results were investigated. SNP genotyping was performed using Sanger sequencing. Hardy-Weinberg Equilibrium, Pearson's Chi square, and student t test were used for analyzing the data using SPSS software version 25. P<0.05 was regarded as statistically significant. Here, 110 COVID-19 patients with and without mucormycosis were investigated. Elevated levels of urea, aspartate aminotransferase, lactate dehydrogenase, and increased ratio of polymorphonuclear neutrophil to lymphocytes were associated with decreased risk of COVID-19-associated mucormycosis in patients (all P<0.05). Moreover, diabetes mellitus increased the risk of mucormycosis (P=0.028). In contrast to patients without mucormycosis, patients with mucormycosis did not display 442 GA and SNP335 GT genotypes. Unlike patients without mucormycosis, none of the patients with mucormycosis had SNP442 GA and SNP335 GT genotypes. Regarding SNP 443 C>T, and the combination of SNPs 582 A>G and 443 C>T, CC genotype and AA+CC genotypes were associated with increased lactate dehydrogenase levels in COVID-19 patients, respectively. Regarding SNP 443 C>T, the CC genotype was associated with increased lactate dehydrogenase levels in COVID-19 patients. In terms of SNP 582 A>G and SNP 443 C>T, COVID-19 patients with AA+CC genotypes had higher levels of LDH. None of the patients with mucormycosis had SNP442 GA and SNP335 GT genotypes.