Search Results (399)

Preeclampsia (PE) is a pregnancy-specific hypertensive disorder characterized by systemic inflammation, endothelial dysfunction, and placental insufficiency. While inadequate trophoblast invasion and impaired spiral artery remodeling have long been recognized as central to its pathogenesis, emerging evidence underscores the critical roles of dysregulated iron metabolism and its crosstalk with immune responses, particularly macrophage-mediated inflammation, in driving PE development. This review systematically explores the dynamic changes in iron metabolism during pregnancy, including increased maternal iron demand, placental iron transport mechanisms, and the molecular regulation of placental iron homeostasis. We further explore the contribution of ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, to trophoblast dysfunction and pregnancy-related diseases, including PE. Macrophages, pivotal immune regulators at the maternal–fetal interface, exhibit distinct polarization states that shape tissue remodeling and immune tolerance. We outline their origin, distribution, and polarization in pregnancy, and emphasize their aberrant phenotype and function in PE. The bidirectional crosstalk between iron and macrophages is also dissected: iron shapes macrophage polarization and function, while macrophages reciprocally modulate iron homeostasis. Notably, excessive reactive oxygen species (ROS) and pro-inflammatory cytokines secreted by M1-polarized macrophages may exacerbate trophoblast ferroptosis, amplifying placental injury. Within the context of PE, we delineate how iron overload and macrophage dysfunction synergize to potentiate placental inflammation and oxidative stress. Key iron-responsive immune pathways, such as the HO-1/hepcidin axis and IL-6/TNF-α signaling, are discussed in relation to disease severity. Finally, we highlight promising therapeutic strategies targeting the iron–immune axis, encompassing three key modalities—iron chelation therapy, precision immunomodulation, and metabolic reprogramming interventions—which may offer novel avenues for PE prevention and treatment. Full article

Background/Objectives: Endometriosis and high-grade serous ovarian cancer (HGS-OC) share common features within the peritoneal immune microenvironment, yet they exhibit divergent clinical outcomes. This study aimed to dissect the immune–metabolic landscape of the peritoneal cavity in patients with endometriosis and ovarian cancer by evaluating macrophage polarization, intracellular signaling pathways, and iron-driven oxidative stress. Methods: A prospective cohort study enrolled 40 patients with endometriosis, 198 with ascitic ovarian cancer (178 HGS-OC), and 200 controls with benign gynecological conditions. Peritoneal and peripheral blood samples were analyzed via flow cytometry for macrophage (M1/M2) polarization markers, mTOR/AKT expression, and glucose uptake. Inflammatory markers (IL-6, CRP), oxidative stress (ROS), and iron metabolism parameters (hepcidin, ferritin, transferrin, serum/free iron) were quantified. Results: HGS-OC displayed a predominance of M1-polarized tumor-associated macrophages (TAMs) (CD14⁺/CD80⁺/Glut1⁺) and a high M1/M2 ratio (2.5 vs. 0.8 and 0.9; p = 0.019), correlating positively with IL-6 (p = 0.015), ROS (p = 0.023), hepcidin (p = 0.038), and ferritin (p = 0.043). Conversely, endometriosis showed a dominant M2 profile (CD14⁺/CD163⁺), elevated intracellular mTOR and AKT expression in both TAMs and epithelial cells (p < 0.01), and significantly higher ascitic ROS and free iron levels (p = 0.047 and p < 0.0001, respectively). In endometriosis, the M1/M2 ratio correlated inversely with free iron (p = 0.041), while ROS levels were directly associated with iron overload (p = 0.0034). Conclusions: Endometriosis exhibits a distinct immune–metabolic phenotype characterized by M2 macrophage predominance and iron-induced oxidative stress, contrasting with the inflammatory, M1-rich profile of HGS-OC. These findings suggest that iron metabolism and macrophage plasticity contribute to disease persistence in endometriosis and may inform future immunomodulatory strategies. Full article

Background: The management of rheumatoid arthritis (RA) has advanced significantly with the introduction of biologic disease-modifying antirheumatic drugs (bDMARDs). Despite these therapeutic strides, RA prognosis remains profoundly affected by comorbid conditions, particularly cardiovascular and metabolic complications, which increase both morbidity and mortality. The role of bDMARDs in modulating comorbidities remains underexplored, with limited evidence on their effects across various non-RA conditions, such as respiratory, diabetic, and hematologic disorders. This systematic review aimed to evaluate the impact of bDMARDs on the progression and outcomes of comorbidities in RA patients, providing insights to guide personalized treatment approaches. Methods: This systematic review was registered in PROSPERO (CRD42022345903) and followed the PRISMA guidelines. Original research articles from PubMed and Scopus, published up to 18 July 2024, were included. Studies assessing the impact of bDMARDs on comorbidities in RA patients met the eligibility criteria. Results: A total of thirteen studies met the inclusion criteria. They were published from inception until July 2024. The studied comorbidities included pulmonary conditions (asthma, chronic obstructive pulmonary disease, and interstitial lung disease) (n = 2); diabetes (n = 3); anemia (n = 3); and malignancies (n = 3). The bDMARDs studied were tumor necrosis factor inhibitors (TNFis) (n = 9); Rituximab (n = 5); Tocilizumab (n = 5); Abatacept (n = 5); and Anakinra (n = 2). The most reported effects of bDMARDs on comorbidities were the following: (i) an exacerbation of pulmonary comorbidities for Abatacept and TNFis; (ii) patients switched to or initiated on Abatacept as their first targeted disease-modifying antirheumatic drug (tDMARD) showed directionally lower rates and costs of T2DM-related complications compared with patients switching to or initiating other tDMARDs; (iii) there was no difference between Abatacept and TNFis or Rituximab/Tocilizumab regarding diabetes treatment switching or intensification; (iv) Anakinra significantly reduced the HbA1c%; (v) decreased serum hepcidin levels and improvement in anemia were observed in patients treated with TNFis or Tocilizumab; and (vi) no decrease in overall survival time or the significant incident malignancy rate was noted in RA patients. Conclusions: Overall, bDMARDs appear safe for use in RA patients with comorbidities and may even provide specific benefits for conditions such as anemia and diabetes. These findings suggest that clinicians could consider tailoring biologic therapy based on each patient’s comorbidity profile, potentially enhancing both RA management and comorbidity outcomes. For instance, selecting biologics such as Anakinra or Tocilizumab might be advantageous for RA patients with concurrent diabetes or anemia, given their observed metabolic and hematologic benefits. This personalized approach could improve the quality of life and reduce healthcare costs by addressing RA and associated comorbidities more effectively. Full article

Iron is unquestionably an essential element of physical performance for horses, just as it is for many other animals, including humans. Although post-exercise equine iron deficiency is not a common problem, recent studies showed that equine athletes may be considered a model for human exercise physiology. Sports anemia among human athletes is a common nutritional issue and remains one reason for poor physical fitness. Thus, this study area needs comprehensive knowledge since iron homeostasis changes in equine athletes remain unrecognized. The current review aims to summarize studies describing iron metabolism changes in response to physical effort in equine sports medicine. The confirmed prevalence of gastrointestinal bleeding, hemolysis, and hematuria in horse athletes seems to play a role in iron metabolism. Similarly, exercise-induced inflammation and its effect on the iron key regulator in mammals—hepcidin—may be as crucial for overall iron homeostasis in horses as in humans. In this review, we also present available data regarding the possible effect of various hormones on iron metabolism, performance-enhancing strategies related to iron metabolism in horse athletes, and the clinical relevance of regular iron status monitoring in sport horses. Overall, this article aims to discuss current knowledge and highlight existing gaps in our understanding of iron homeostasis in sport horses. Full article

Heat shock proteins (HSPs), particularly HSP70, play a vital role in fish immune defense against pathogens. The administration of DnaK (bacterial homolog of HSP70) may be a strategy to potentiate the immune response and survival of aquatic organisms. This study evaluates the effect of cells overexpressing DnaK on mortality and immune-related gene expression in gnotobiotic sea bass larvae challenged with Vibrio anguillarum. Larvae were subjected to different treatments: NB (no bacteria), YS0 (E. coli with no plasmid), YS1 (E. coli expressing truncated DnaK), and YS2 (E. coli expressing DnaK), and then infected with V. anguillarum at 7 days post-hatching (dph). Mortality was monitored, and RT-qPCR was used to evaluate immune gene expression at 0, 18, 24, 36, and 120 hpc. While no significant variations were recorded in the non-challenged larvae, constant and sustained mortality was observed in challenged larvae from 60 to 120 hpc. However, lower mortality was observed in the larvae treated with DnaK. DnaK treatment promoted the expression of antimicrobial (hepcidin, transferrin) and chemotaxis genes (ccl4), which was further enhanced after a challenge with V. anguillarum, in conjunction with the modulation of il1β and il-8 at 120 hpc. These findings suggest that DnaK induces a potent innate immune response, improving survival against V. anguillarum and supporting its potential use as a disease-preventive strategy in aquaculture. Full article

Mycobacterium marinum is an opportunistic pathogen prevalent in aquatic environments, causing significant morbidity in fish, including Coho salmon (Oncorhynchus kisutch), a species increasingly cultured in Chinese salmonid aquaculture. This study investigated the immune response of Coho salmon to M. marinum infection and the bacterial proliferation dynamics in the liver and kidney. Transcriptome analysis revealed 5028 differentially expressed genes (DEGs) in the kidney and 3419 DEGs in the liver at 6 weeks post-infection. Gene Ontology and KEGG enrichment analysis highlighted pathways such as cytokine–cytokine receptor interaction, metabolic pathways, and Toll-like receptor signaling in the kidney, while the DEGs in the liver were enriched in metabolic pathways, immune system processes, and stress and defense responses. The temporal expression profiling of 15 immune-related genes, including acute-phase proteins (serum amyloid A-5 and hepcidin), cytokines (TNF-α, IL-1β, IL-17A), chemokines (CXCL13 and CCL19), pattern recognition receptors (Toll-like receptor 13), and other immune-related genes, showed significant upregulation against M. marinum infection, with stronger responses in the liver. Furthermore, it was found that there was a progressive proliferation of M. marinum in the infected liver and kidney from approximately 2.5 log₁₀ cfu/g at week 2 to about 6 log₁₀ cfu/g by 6 weeks, with a significantly higher load in the liver. These findings provide critical insights into the immune mechanisms of Coho salmon against M. marinum and the pathogen’s tissue-specific proliferation, offering a foundation for developing targeted control strategies against M. marinum in aquaculture. Full article

Hepcidin is a key regulator of systemic iron homeostasis, which is essential for maintaining iron balance and cellular health. To investigate its role in zebrafish, we empolyed a hepcidin knockout model. Morphological and histological analyses revealed pale livers and significant iron accumulation in hep^−/− zebrafish, particularly in liver, skin, and egg tissues. RNA sequencing identified 1,424 differentially expressed genes (DEGs) between wild-type (WT) and hep^−/− zebrafish, with significant enrichment in pathways related to ferroptosis, fatty acid degradation, and heme binding. Western blot analysis showed reduced levels of key iron-related proteins, including GPX4, Fth1, and ferroportin (FPN), indicating impaired iron transport and increased oxidative stress. Gene Ontology (GO) and KEGG analyses highlighted disruptions in iron metabolism and lipid oxidation, linking iron overload to ferroptosis in the absence of hepcidin. These findings demonstrate that hepcidin deficiency leads to profound dysregulation of iron homeostasis, driving lipid peroxidation and ferroptosis in the zebrafish liver. Our study provides mechanistic insights into the molecular consequences of hepcidin loss, advancing our understanding of iron-related oxidative damage and its physiological impacts. Full article

Iron deficiency is highly prevalent in patients with idiopathic pulmonary hypertension; nevertheless, its role and clinical significance in hypoxic pulmonary hypertension (HPH) remain elusive. Therefore, this study aims to clarify the role and molecular mechanisms of iron in HPH. By means of a retrospective analysis of clinical data from HPH patients and examinations of HPH animal models, we discovered that both HPH patients and animal models exhibit significant iron deficiency, characterized by reduced hepatic iron storage and elevated hepcidin expression. To further explore iron’s role in HPH, we modulated iron metabolism through pharmacological and dietary interventions in chronic hypoxic animal models. The results showed that iron deficiency exacerbated chronic hypoxia-induced pulmonary hypertension and right ventricular hypertrophy, while iron supplementation alleviated these conditions. Further investigations revealed that iron regulates HIF2α expression in pulmonary arterial endothelial cells (PAECs) under chronic hypoxia. Therefore, through in vivo and in vitro experiments, we demonstrated that HIF2α inhibition attenuates chronic hypoxia-induced pulmonary hypertension and right ventricular hypertrophy. Mechanistically, chronic hypoxia-mediated iron deficiency enhances HIF2α activation, subsequently suppressing iron/sulfur cluster assembly enzyme (ISCU) expression. This leads to decreased mitochondrial complexes I and III activity, increased reactive oxygen species (ROS) production, and inhibited oxidative phosphorylation. Consequently, metabolic reprogramming in PAECs results in a proliferation/apoptosis imbalance, ultimately exacerbating hypoxia-induced pulmonary hypertension and right ventricular hypertrophy. Collectively, our findings demonstrate that iron supplementation mitigates HPH progression by modulating HIF2α-mediated metabolic reprogramming in PAECs, revealing multiple therapeutic targets for HPH. Full article

Sepsis, defined as a dysregulated host response to infection, is one of the leading causes of mortality worldwide. It unleashes in the organism a cascade of molecules, cytokines, and proteins which leads to an inflammatory storm. If this response to infection is uncontrolled, any organ is susceptible to damage. Acute kidney injury (AKI) is one of the most frequent organ dysfunctions in septic patients, and while it can be reversible, its presence leads to a higher burden of morbidity and mortality. While serum creatinine is essential in evaluating kidney function, the pathophysiology of AKI is not completely elucidated, and a plethora of novel biomarkers have been studied in the hope of an early diagnosis and fast treatment. While the liver is not as affected by sepsis, it plays an important role as a guardian by providing acute-phase proteins, activating neutrophils, and controlling iron balance. Acute liver failure (ALF) could impair the organism’s capacity to contain and eliminate pathogens. Some molecules have been associated with either AKI or ALF, although biomarkers specific for organ dysfunction are difficult to validate. The aim of this review is to understand the role of several molecules in the pathophysiology of sepsis and their clinical ability for diagnosing or predicting sepsis-induced hepato-renal dysfunction. Full article

Chronic stress can lead to nervous system dysfunction and depression-like behaviors in animals. Gypenosides can improve chronic stress-induced neuronal damage, but the protective mechanism remains poorly understood. This study aims to investigate the effect and mechanism of gypenosides on chronic stress-induced neuronal ferroptosis. Therefore, we established a chronic stress-induced neuronal damage model in vitro using corticosterone to induce PC12 cell injury. We demonstrated that ferroptosis inhibitors DFO and Ferrostatin-1 alleviated corticosterone-induced cell death in PC12 cells by reducing iron accumulation, lipid peroxidation, and increasing cell viability. Meanwhile, gypenosides attenuated ferroptosis agonist Erastin-induced ferroptosis in PC12 cells. Then, gypenosides ameliorated corticosterone-induced ferroptosis in PC12 cells. In terms of molecular mechanisms, gypenosides decreased the expression of Hepcidin and DMT1, and increased the expression of Ferritin and FPN1, thereby improving corticosterone-induced iron homeostasis disorders and iron accumulation. Moreover, gypenosides improved corticosterone-induced lipid peroxidation by inhibiting GLS2 expression, upregulating the expression of SLC7A11 and glutathione peroxidase 4, and reducing glutamate accumulation and GSH depletion. Gypenosides also reduced corticosterone-induced release of inflammatory cytokines, the expression of TNFR1, and the phosphorylation of NF-κB and p53 in PC12 cells. These findings indicate that gypenosides attenuate corticosterone-induced ferroptosis by inhibiting TNF-α/NF-κB signaling pathway in PC12 cells. Full article

In older adults with reduced physical performance, an increase in the labile iron pool within skeletal muscle is observed. This accumulation is associated with an altered expression of mitochondrial quality control (MQC) markers and increased mitochondrial DNA damage, supporting the hypothesis that impaired MQC contributes to muscle dysfunction during aging. The autophagy–lysosome system plays a critical role in MQC by tagging and engulfing proteins and organelles for degradation in lysosomes. The endolysosomal system is also instrumental in transferrin recycling, which, in turn, regulates cellular iron uptake. In the neuromuscular system, the autophagy–lysosome system supports the structural integrity of neuromuscular junctions, and its dysfunction contributes to muscle atrophy. While MQC was thought to protect against iron-induced cell death, the discovery of ferroptosis, a form of iron-dependent cell death, has highlighted a complex interplay between MQC and iron-inflicted damage. Ferritinophagy, the autophagic degradation of ferritin, if overactivated, can induce ferroptosis. Alternatively, aging may impair ferritinophagy, leading to ferritin accumulation and the release of toxic labile iron under stress, exacerbating oxidative damage and cellular senescence. Physical activity supports muscle health also by preserving mitochondrial quantity and quality and enhancing bioenergetics. However, therapeutic strategies for preventing or reversing physical function decline in aging are still lacking due to the insufficient understanding of the underlying mechanisms. Unveiling how disruptions in iron homeostasis impact muscle quality in older adults may allow for the development of therapeutic strategies targeting iron handling to alleviate age-associated muscle decline. Full article

Background/Objective: Patients with beta-thalassemia are more susceptible to iron overload and have altered neutrophil function. This study investigated the connections between iron metabolism in neutrophils, neutrophil functionality, and overall iron status in individuals with β-thalassemia and sickle cell anemia. Methods: We recruited 18 patients with β-thalassemia, 5 patients with sickle cell anemia, and 15 healthy controls. Our evaluation included measurements of iron and hepcidin concentrations in the serum, along with an analysis of neutrophil function, specifically their phagocytic and oxidative burst capabilities. In addition, we examined the expression of iron transport proteins in neutrophils. Results: Patients with β-thalassemia showed significant iron overload, reduced neutrophil counts, and decreased oxidative burst activity and phagocytosis. Systemic iron status is inversely correlated with the phagocytic capacity of β-thalassemia neutrophils. Regression analysis indicated a significant association between serum iron level, transferrin iron binding capacity, transferrin saturation, and neutrophil percentage. These findings elucidate the essential role of systemic iron levels in neutrophil efficacy against infections. Furthermore, FPN1B and DMT1A mRNA levels were upregulated, and IRP2 was downregulated in the neutrophils of patients with β-thalassemia major and intermedia compared to controls. Conclusions: Elevated systemic iron levels were associated with reduced neutrophil counts and impaired neutrophil function in patients with β-thalassemia. These findings highlight a critical role of systemic iron overload in neutrophil dysfunction. Full article

Macrophages play a crucial role in maintaining intestinal homeostasis and can exhibit either pro-inflammatory M1 or anti-inflammatory M2 phenotypes. The cannabinoid receptor type 2 (CB2) is involved in immune regulation and may represent a therapeutic target in inflammatory bowel disease (IBD). Our study investigates the phenotype of circulating macrophages and CB2 expression in children with IBD, assessing the role of CB2 stimulation in macrophage polarization, iron metabolism, and intestinal barrier function. Macrophages were isolated from 17 children with ulcerative colitis (UC), 21 with Crohn’s disease (CD), and 12 healthy controls (CTR). Cells were treated with a CB2 agonist (JWH-133) and an inverse agonist (AM630). CB2 expression and macrophage polarization were assessed by Western blot. Iron metabolism was evaluated through IL-6, hepcidin levels, FPN-1 expression, and iron concentration. Inflammation was assessed by cytokine release. An in vitro “immunocompetent gut” model was used to study the effects of CB2 stimulation on macrophage polarization and intestinal barrier function. CB2 expression was reduced in IBD macrophages. Compared to controls, IBD patients showed increased M1 markers and pro-inflammatory cytokines, with a reduction in M2 markers and IL-13. Altered iron metabolism was observed, with increased [Fe³⁺], hepcidin release, and DMT1 expression, and reduced FPN-1. CB2 stimulation restored iron metabolism, induced M2 polarization, and improved intestinal barrier function. CB2 could represent a novel therapeutic target for IBD by modulating macrophage function, iron metabolism, and mucosal barrier restoration. Full article

Background/Objectives: Hepcidin is a negative regulator of iron absorption that is released by hepatocytes. It is one of the main contributors to hypoferremia and anemia in inflammatory and oncological disorders that are mediated by the proinflammatory cytokine IL-6/STAT3 pathway. Ferulic acid (FA) is a phenolic compound with pleiotropic biological activities, including anti-inflammatory activity. However, its effect on hepcidin secretion is still unknown. Thus, this study aimed to explore the impact of FA on hepcidin levels and the underlying mechanism. Methods: HepG2 cells were treated with different log percentages of FA, and their viability was determined via the MTT assay. The relative expression of IL-6 and HAMP in treated and untreated cells was measured via qRT-PCR, and the protein levels of hepcidin, IL-6 and STAT3 were measured using ELISA. Results: The MTT test showed an inverse relationship between FA concentrations and HepG2 cell proliferation; FA’s IC₅₀ value was 0.07669%. The expression levels of IL-6 and HAMP were significantly increased in HepG2 cells following 24 h of culture with 4 μg/mL LPS. Meanwhile, the addition of FA significantly decreased the relative expression levels of these two genes and the secretion levels of IL-6, STAT3 and hepcidin compared to the cells treated with LPS alone. Conclusions: Overall, these findings show that FA modifies inflammatory pathways, affecting hepcidin levels via the IL-6/STAT3 pathway. Thus, this suggests FA as a potential therapeutic agent against the hypoferremia and anemia developed due to dysregulated hepcidin levels in diseases such as inflammatory and oncological disorders. Full article