Revealing hidden risks: in vitro analysis of PFAS hazards in Mytilus galloprovincialis gills and digestive gland

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals known for their persistence and bioaccumulation, leading to widespread environmental contamination. Despite their recognised environmental risks, particularly to aquatic wildlife, including marine invertebrates, detailed impact studies are limited. PFAS can be categorised according to the length of the compound chain, with short-chain PFAS announced as a safer alternative to the more commonly used long-chain PFAS. However, recent evidence suggests that also short-chain PFAS pose significant environmental risks. The present study evaluated the adverse effects of six PFAS compounds-two short-chain (PFHxA, 6:2 FTA) and four long-chain (PFUnDA, PFDoA, PFTriDA, PFTeDA)- on the digestive gland and gills of mussels, Mytilus galloprovincialis, using in vitro assays. The results showed organ-specific responses: the digestive gland was more sensitive to PFHxA, with increased catalase activity and decreased total antioxidant capacity, and cellular damage was observed only at higher concentrations of PFTriDA. Gills were more affected by PFDoA and PFTeDA, with inhibited antioxidant enzyme activity and increased oxidative stress. PFHxA and PFTriDA also showed inhibition of acetylcholinesterase activity. 6:2 FTA had the lowest effects for both organs, while PFHxA was the most harmful. These findings underscore the need for thorough risk assessments of PFAS, considering both chain length and organ-specific effects.

Arylsulfonothioates: Thiol-Activated Donors of Hydropersulfides which are Excreted to Maintain Cellular Redox Homeostasis or Retained to Counter Oxidative Stress

Despite their biological significance, the study of hydropersulfides (RSSH) is often limited due to their inherent instability. Here, we introduce arylsulfonothioates as thiol-activated RSSH donors and provide insight into cellular reactive sulfur species homeostasis. These precursors persulfidate physiologically relevant thiols (RSH) to form the corresponding RSSH. Real-time monitoring of hydrogen sulfide (H2S) generation via membrane inlet mass spectrometry (MIMS) was employed to follow RSSH production, revealing that electron-donating aryl substituents marginally slow RSSH release rates, whereas electron-withdrawing substituents slightly accelerate release. Furthermore, arylsulfonothioates with strong electron-withdrawing substituents offer superior protection against doxorubicin (DOX)-induced cardiotoxicity. Experiments using H9c2 cardiomyocytes affirmed the cell-permeability of arylsulfonothioates and their ability to increase intracellular RSSH levels and protein persulfidation levels. Notably, we observe the excretion of RSSH into the extracellular medium. Further investigations revealed the involvement of the cystine/glutamate antiporter SLC7A11, as cotreatment with its inhibitor, sulfasalazine, significantly reduce extracellular RSSH release. H9c2 cells exhibit tolerance to arylsulfonothioate 1g with an electron-withdrawing 4-cyano group at 1 mM; however, inhibition of the cystine antiporter results in a minor decrease in cell viability. Under oxidative stress conditions induced by DOX or hydrogen peroxide (H2O2), cotreatment with 1g diminishes the excretion of RSSH and confers cytoprotection against DOX or H2O2-mediated toxicity. Our findings show adaptive cellular responses to RSSH levels, demonstrating excretion under elevated conditions to maintain redox homeostasis and intracellular retention as a protective response during oxidative stress.

Pulling back the mitochondria's iron curtain

Mitochondrial functionality and cellular iron homeostasis are closely intertwined. Mitochondria are biosynthetic hubs for essential iron cofactors such as iron-sulfur (Fe-S) clusters and heme. These cofactors, in turn, enable key mitochondrial pathways, such as energy and metabolite production. Mishandling of mitochondrial iron is associated with a spectrum of human pathologies ranging from rare genetic disorders to common conditions. Here, we review mitochondrial iron utilization and its intersection with disease.

Label-Free Quantification of Apoptosis and Necrosis Using Stimulated Raman Scattering Microscopy

Recombinant proteins are critical for modern therapeutics and diagnostics, with Chinese hamster ovary (CHO) cells serving as the primary production platform. However, environmental and chemical stressors in bioreactors often trigger cell death, particularly apoptosis, posing a significant challenge to recombinant protein manufacturing. Rapid, label-free methods to monitor cell death are essential for ensuring better production quality. Stimulated Raman scattering (SRS) microscopy offers a powerful, label-free approach to measure lipid and protein compositions in live cells. We demonstrate that SRS microscopy enables rapid and reagent-free analysis of apoptotic and necrotic transitions. Our results show that apoptotic cells exhibit higher protein concentrations, while necrotic cells show an opposite trend. To enhance analysis, we developed a quantitative single-cell analysis pipeline that extracts chemotypic and phenotypic signatures of apoptosis and necrosis, enabling the identification of subpopulations with varied responses to stressors or treatments. Furthermore, the cell death analysis was successfully generalized to other stressors and cell types. This study highlights SRS microscopy as a robust and non-invasive tool for rapid monitoring of live cell apoptotic and necrotic transitions. Our method and findings hold potential for improving quality control in CHO cell-based biopharmaceutical production and for evaluating cell death in diverse biological contexts.

17β-Trenbolone Exposure Enhances Muscle Activity and Exacerbates Parkinson's Disease Progression in Male Mice

Parkinson's disease (PD) ranks as the second most prevalent neurodegenerative disorder, and while the neuroprotective effects of estrogen are well-documented, the impact of androgens on neurological disorders remains understudied. The consequences of exposure to 17-trenbolone (17-TB), an environmental endocrine disruptor with androgen-like properties, on the mammalian nervous system have received limited attention. Therefore, in this study, we aimed to investigate the biological effects of 17-TB exposure on PD. In our investigation using the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model, we discovered that 17-TB exposure elevated testosterone hormone levels prevented androgen receptor (AR) reduction, upregulated the expression of muscular dystrophic factors (Atrogin1, MuRF1, Musa1, and Myostatin), improved muscle strength, and enhanced locomotor activity in the open field test. However, it is noteworthy that exposure to 17-TB also led to an upregulation of neuroinflammatory cytokines (NLRP3, IL-6, IL-1α, and IL-1β) in PD mice. Crucially, 17-TB exposure induced downregulation of nigral apoptotic proteins DJ-1 and Bcl-2 while upregulating Bax and Caspase-3 in PD mice. This exacerbated neuronal apoptosis, ultimately intensifying dopaminergic neuronal degeneration and death in the substantia nigra and striatum of PD mice. In conclusion, our findings indicate that while 17-TB mitigates muscle atrophy and enhances motor activity in PD mice, it concurrently exacerbates neuroinflammation, induces neuronal apoptosis, and worsens dopaminergic neuronal death, thereby aggravating the progression of MPTP-induced Parkinsonism. This underscores the importance of considering potential environmental risks in neurodegeneration associated with Parkinson's disease, providing a cautionary tale for our daily exposure to environmental endocrine chemical disruptors.

Exosome-Derived CDC42 From Hypoxia-Pretreated Neural Stem Cells Inhibits ACSL4-Related Ferroptosis to Alleviate Vascular Injury in Parkinson's Disease Mice Models

Parkinson's disease (PD) is a neurodegenerative disorder that gets exacerbated by vascular injury. Neural stem cell-derived exosomes (NSC-Exos) display effective neuroprotective properties in PD models. Cell division control protein 42 (CDC42) is connected to angiogenesis, but its effects in PD remain undefined. This research aims to reveal the role of CDC42 in PD. First, we applied 1-methyl-4-phenylpyridinium (MPP+) to induce the human cerebral microvascular endothelial cells (HCMECs) model and evaluated cell viability and ferroptosis. Then, we characterized NSC-Exos. Next, to appraise the effect of hypoxia-pretreated NSC-Exos (H-NSC-Exos) on the MPP+-induced cells model, we examined angiogenesis and ferroptosis in HCMECs. Moreover, we constructed the PD mice model using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and tested the behavioral experiments and vascular injury of mice. Furthermore, we examined cellular ferroptosis and angiogenesis after knockdown of CDC42. Additionally, we investigated the interaction of CDC42 with Acyl-CoA synthetase long-chain family member 4 (ACSL4) and detected cellular ferroptosis and angiogenesis after overexpression of ACSL4. We found that H-NSC-Exos reversed the MPP+-induced decrease in HCMECs viability and migration, lowered lipid-reactive oxygen species (lipid-ROS) levels, suppressed ferroptosis, and facilitated angiogenesis. Moreover, H-NSC-Exos attenuated MPTP-induced PD development, vascular injury, and ferroptosis in mice. H-NSC-Exos with the knockdown of CDC42 reduced cell viability and angiogenesis and raised ferroptosis and lipid-ROS levels, which were reversed by ferrostatin-1 and liproxstatin-1. CDC42 interacted with ACSL4. Furthermore, overexpression of ACSL4 aggravated the above effects of H-NSC-Exos in which CDC42 was knocked down. Our study reveals that H-NSC-Exos-derived CDC42 inhibited ACSL4-related ferroptosis to alleviate vascular injury in PD mice models. CDC42 may serve as a potent therapeutic target for PD treatment.

Mild cognitive impairment in amyotrophic lateral sclerosis: current view

Amyotrophic lateral sclerosis (ALS) is a fatal multi-system neurodegenerative disorder with no effective treatment or cure. Although primarily characterized by motor degeneration, cognitive dysfunction is an important non-motor symptom that has a negative impact on patient and caregiver burden. Mild cognitive deficits are present in a subgroup of non-demented patients with ALS, often preceding motor symptoms. Detailed neuropsychological assessments reveal deficits in a variety of cognitive domains, including those of verbal fluency and retrieval, language, executive function, attention and verbal memory. Mild cognitive impairment (MCI), a risk factor for developing dementia, affects between 10% and over 50% of ALS patients. Neuroimaging revealed atrophy of frontal and temporal cortices, disordered white matter Integrity, volume reduction in amygdala and thalamus, hypometabolism in the frontal and superior temporal gyrus and anterior insula. Neuronal loss in non-motor brain areas, associated with TDP-43 deposition, one of the morphological hallmarks of ALS, is linked to functional disruption of frontostriatal and frontotemporo-limbic connectivities as markers for cognitive deficits in ALS, the pathogenesis of which is still poorly understood. Early diagnosis by increased cerebrospinal fluid or serum levels of neurofilament light/heavy chain or glial fibrillary acidic protein awaits confirmation for MCI in ALS. These fluid biomarkers and early detection of brain connectivity signatures before structural changes will be helpful not only in establishing early premature diagnosis but also in clarifying the pathophysiological mechanisms of MCI in ALS, which might serve as novel targets for prohibition/delay and future adequate treatment of this debilitating disorder.

Signaling pathways of pro-IL-1β production induced by mechanical stress in gingival epithelial cells

OBJECTIVES

Mechanical stress on the teeth and alveolar bone caused by bruxism, orthodontics, and implants affects the periodontal tissues, causing gingival recession and alveolar bone resorption, and entire body, including the heart and vascular system. Although the same forces exerted on the alveolar bone and teeth are exerted on gingival epithelial cells, little is known about the effects of mechanical stress on these cells. This study investigated the effects of mechanical stress on gingival epithelial cells.

METHODS

Ca9-22 cells (human gingival epithelial cells) were used. They were seeded onto the silicone and stretched cyclically. Mechanical stress-stimulated Ca9-22 cells were evaluated for pro-inflammatory interleukin (pro-IL)-1β production using Western blotting and analyzed to assess the phosphorylation level of intracellular signaling molecules.

RESULTS

Mechanical stress induced pro-IL-1β upregulation in Ca9-22 cells, which was significantly inhibited by ruthenium red. Ruthenium red significantly inhibited mechanical stress-induced phosphorylation of focal adhesion kinase (FAK), P130cas, and extracellular signal-regulated kinase 1 and 2 (ERK1/2) induced by mechanical stress. Additionally, Y15 significantly inhibited the upregulation of pro-IL-1β expression and phosphorylation of FAK, P130cas, and ERK1/2 stimulated by mechanical stress.

CONCLUSIONS

In Ca9-22 cells, mechanical stress may increase pro-IL-1β production via mechanosensitive ion channels and FAK. These findings revealed the mechanisms of inflammation in mechanically-stressed Ca9-22 cells and may aid in the development of therapeutic approaches to prevent bone resorption.

Activating the NFE2L1-ubiquitin-proteasome system by DDI2 protects from ferroptosis

Ferroptosis is an iron-dependent, non-apoptotic form of cell death initiated by oxidative stress and lipid peroxidation. Recent evidence has linked ferroptosis to the action of the transcription factor Nuclear factor erythroid-2 derived,-like-1 (NFE2L1). NFE2L1 regulates proteasome abundance in an adaptive fashion, maintaining protein quality control to secure cellular homeostasis, but the regulation of NFE2L1 during ferroptosis and the role of the ubiquitin-proteasome system (UPS) herein are still unclear. In the present study, using an unbiased proteomic approach charting the specific ubiquitylation sites, we show that induction of ferroptosis leads to recalibration of the UPS. RSL3-induced ferroptosis inhibits proteasome activity and leads to global hyperubiquitylation, which is linked to NFE2L1 activation. As NFE2L1 resides in the endoplasmic reticulum tethered to the membrane, it undergoes complex posttranslational modification steps to become active and induce the expression of proteasome subunit genes. We show that proteolytic cleavage of NFE2L1 by the aspartyl protease DNA-damage inducible 1 homolog 2 (DDI2) is a critical step for the ferroptosis-induced feed-back loop of proteasome function. Cells lacking DDI2 cannot activate NFE2L1 in response to RSL3 and show global hyperubiquitylation. Genetic or chemical induction of ferroptosis in cells with a disrupted DDI2-NFE2L1 pathway diminishes proteasomal activity and promotes cell death. Also, treating cells with the clinical drug nelfinavir, which inhibits DDI2, sensitized cells to ferroptosis. In conclusion, our results provide new insight into the importance of the UPS in ferroptosis and highlight the role of the DDI2-NFE2L1 as a potential therapeutic target. Manipulating DDI2-NFE2L1 activity through chemical inhibition might help sensitizing cells to ferroptosis, thus enhancing existing cancer therapies.

COPB1 deficiency triggers osteoporosis with elevated iron stores by inducing osteoblast ferroptosis

Background

Osteoporosis (OP) is a systemic bone metabolic disease that results from an imbalance between bone formation and bone resorption. The accumulation of iron has been identified as an independent risk factor for osteoporosis. Ferroptosis, a novel form of programmed cell death, is driven by iron-dependent lipid peroxidation. Nevertheless, the precise role of ferroptosis in iron accumulation-induced osteoporosis remains uncertain.

Methods

We utilized proteomics and ELISA to screen key regulatory molecules related to iron accumulation in osteoporosis populations. HE staining was used to assess osteocyte changes in Hamp knockout (KO) iron accumulation mouse models. Western Blot, qPCR, ALP staining, and Alizarin Red staining were employed to explore the effects of siRNA-mediated gene knockdown on osteogenic differentiation in the MC3T3 cell line. ELISA, micro-CT, von Kossa staining, toluidine blue staining, TRAP staining, and calcein analysis were used to study the bone phenotype of conditional gene knockout mice. RNA-seq, endoplasmic reticulum activity probes, transmission electron microscopy (TEM), Western Blot, co-immunoprecipitation (Co-IP), flow cytometry, and ChIP-seq were employed to investigate the regulatory mechanisms of the target gene in osteogenic differentiation. OVX and Hamp KO mice were used to establish osteoporosis models, and AAV-mediated overexpression was employed to explore the intervention effects of the target gene on osteoporosis.

Results

The experiments demonstrate that iron accumulation can lead to changes in COPB1 expression levels in bone tissue. Cellular and animal experiments revealed that COPB1 deficiency reduces the osteogenic ability of osteoblasts. Transcriptome analysis and phenotypic experiments revealed that COPB1 deficiency induces ferroptosis and endoplasmic reticulum stress in cells. Further investigation confirmed that COPB1 plays a key role in endoplasmic reticulum stress by inhibits SLC7A11 transcription via ATF6. This reduces cystine uptake, ultimately inducing ferroptosis. Overexpression of COPB1 can restore osteogenic function in both cells and mice.

Conclusion

This study elucidated the essential role of COPB1 in maintaining bone homeostasis and highlights it as a potential therapeutic target for treating iron accumulation-related osteoporosis.

The translational potential of this article

Our data elucidate the critical role of COPB1 in maintaining bone homeostasis and demonstrate that COPB1 can directly promote bone formation, making it a potential therapeutic target for the future treatment of osteoporosis.

Urinary glyphosate, selenium status, and their impact on mortality: Evidence from NHANES 2013-2018

PURPOSE

Glyphosate and glyphosate-based herbicides (GBHs), extensively used worldwide, have been associated with various health concerns, including an elevated risk of mortality. Experimental studies suggest that these herbicides may disrupt selenium homeostasis by hindering its uptake or promoting oxidative stress. However, the interplay between glyphosate exposure and selenium status remains poorly understood in epidemiological studies, particularly regarding selenium's role in modulating the mortality risk associated with glyphosate exposure in nationally representative populations.

APPROACH AND RESULTS

In this study, we analyzed data from the 2013-2018 National Health and Nutrition Examination Survey (NHANES), which included 6410 participants aged 3 years and older. This dataset was linked to mortality information from the National Center for Health Statistics (NCHS) for individuals aged 18 and older, with follow-up through 2019. The primary aim was to investigate the relationships between urinary glyphosate levels, whole blood selenium, selenium intake, and the influence of selenium status on glyphosate-related all-cause mortality risk. A significant negative correlation was observed between the natural logarithm (ln) of urinary glyphosate levels and the ln of whole blood selenium in the complex multiple linear regression models, with a ß coefficient of -0.010 (SE = 0.003, P = 0.003). However, no association was found between urinary glyphosate levels and selenium intake. Furthermore, the association was particularly prominent among females, non-Hispanic whites, and individuals with lower selenium intake. When examining the relationship between glyphosate exposure, whole blood selenium levels, and all-cause mortality, higher ln-urinary glyphosate levels were significantly associated with an increased risk of mortality (Hazard Ratio [HR] = 1.43; 95 % CI: 1.00-2.09). This elevated risk was especially pronounced in individuals with whole blood selenium concentrations at or above the 50th percentile. Additionally, ln-whole blood selenium was associated with a protective effect against all-cause mortality (HR = 0.01; 95 % CI: 0.00-0.18), with the strongest protective effect observed in individuals with selenium levels below the 50th percentile.

CONCLUSIONS

In this comprehensive analysis of NHANES data, our study identifies a potentially harmful relationship between glyphosate exposure and whole blood selenium levels. Notably, excessively high whole blood selenium levels may not only reduce the protective effects against all-cause mortality but could also increase the risk of glyphosate-related mortality, suggesting a U-shaped relationship between selenium levels and mortality risk. These findings highlight the need for further research into the health effects of glyphosate exposure and its interaction with selenium status, emphasizing the potential public health implications.

SRXN1 is a novel protective factor against methylmercury-induced apoptosis in C17.2 mouse neural stem cells

Methylmercury is an environmental pollutant that exhibits severe cerebral neurotoxicity and remains a worldwide problem. Motor and mental development disorders have been observed in children born to women who consumed relatively large amounts of methylmercury via contaminated fish during pregnancy. We previously found by RNA-sequencing analysis that treatment of C17.2 mouse neural stem cells with methylmercury induced the expression of SRXN1 (sulfiredoxin-1), a redox regulator. In this study, we examined the effect of methylmercury on SRXN1 expression and the role of SRXN1 in methylmercury-induced cell death. After C17.2 cells were treated with methylmercury, both mRNA and protein expression of SRXN1 increased in a time- and concentration-dependent manner. Because the induction of SRXN1 expression by methylmercury was suppressed by pretreatment with a transcription inhibitor, we searched the upstream region of the SRXN1 gene and found a binding sequence for transcription factor 3 (TCF3). Interestingly, the induction of SRXN1 expression by methylmercury was attenuated in cells in which TCF3 expression was suppressed by siRNA compared with control cells. This suggests that TCF3 is involved in the induction of SRXN1 expression by methylmercury. We previously reported that TCF3 overexpression suppressed methylmercury-induced apoptosis; in the present study, we found that SRXN1 overexpression also suppressed methylmercury-induced apoptosis, as assessed by cleaved caspase-3 expression. In summary, our results indicate that SRXN1 induced by TCF3-mediated expression is a novel protective factor against methylmercury-induced apoptosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-024-00277-6.

Associations of multiple plasma metals with the risk of type 2 diabetes in Chinese adults: A cross-sectional study

Evidence regarding the associations between co-exposure to multiple metals and diabetes risk was scarce. This study aimed to evaluate the associations of multiple metals with diabetes risk using multiple statistical methods. This cross-sectional study included 192 diabetic patients and 189 healthy subjects. We employed inductively coupled plasma mass spectrometry (ICP-MS) to determine the plasma concentrations of 18 metals. Least absolute shrinkage and selection operator (LASSO) regression, logistic regression, and Bayesian kernel machine regression (BKMR) were applied to evaluate associations of multiple metals with diabetes risk comprehensively. These models consistently suggested that aluminium and selenium were positively associated with diabetes risk, while manganese, rubidium, and lead were negatively associated with diabetes risk. Age-specific differences of selenium and sex-specific differences of manganese in diabetes risk were also observed based on stratified analyses. According to RCS analyses, we obtained dose-response relationships between metals and diabetes risk:(1) there were inverted U-shaped associations of plasma aluminium and selenium with diabetes risk, with the threshold close to 20.5µg/L and 75.9µg/L, respectively (both P for overall < 0.05; both P for non-linearity < 0.05). (2) There were L-shaped associations of rubidium and lead with diabetes risk, with the turning point close to 144.5µg/L and 2.5µg/L, respectively (both P for overall < 0.05; both P for non-linearity < 0.05). (3) Manganese was linearly and negatively correlated with diabetes risk when concentrations of manganese were less than approximately 4.2 μg/L (P for overall < 0.05; P for non-linearity = 0.268). The BKMR model also revealed a negative combined effect of metal mixtures on diabetes risk and potential interactions between six pairs of metals (aluminium-manganese, aluminium-selenium, aluminium-rubidium, aluminium-lead, manganese-selenium, and manganese-rubidium). In summary, we need to pay attention to the role of low plasma levels of aluminium, selenium, manganese, rubidium, and lead in diabetes, especially regarding their safety windows.

Identification of ferroptosis-related genes in heart tissues of patients with hypertrophic cardiomyopathy

BACKGROUND

This study aims to investigate the role of ferroptosis in hypertrophic cardiomyopathy (HCM), a genetic disorder characterized by abnormal thickening of the heart muscle. The objective is to identify differentially expressed genes associated with ferroptosis in HCM and understand the potential molecular mechanisms underlying the disease.

METHODS

Comprehensive genomic analysis was conducted to identify differentially expressed genes associated with ferroptosis in HCM. The analysis focused on TFRC, SCD, SLC2A1, EGR1, GDF15, SNCA, PLIN2, and NQO1 as hub genes regulating ferroptosis. Functional enrichment analysis was performed to uncover their involvement in pathways such as ferroptosis, ubiquinone biosynthesis, and HIF-1 signaling. In addition, immune cell infiltration patterns in HCM were explored, and associations between the hub genes and immune infiltration were identified.

RESULTS

The analysis revealed TFRC, SCD, SLC2A1, EGR1, GDF15, SNCA, PLIN2, and NQO1 as hub genes involved in the regulation of ferroptosis in HCM. Functional enrichment analysis indicated their contribution to key pathways related to ferroptosis, ubiquinone biosynthesis, and HIF-1 signaling. Furthermore, associations between the hub genes and immune infiltration in HCM were observed.

CONCLUSION

This study provides valuable insights into the molecular basis of HCM by identifying differentially expressed genes associated with ferroptosis. The findings suggest potential molecular mechanisms underlying the development of HCM. These findings contribute to a better understanding of HCM and may pave the way for the development of targeted therapies and improved diagnostic approaches for this debilitating cardiac disorder.

Selenium as an Antioxidant: Roles and Clinical Applications in Critically Ill and Trauma Patients: A Narrative Review

Selenium plays an indispensable role in antioxidant defense through its incorporation into selenoproteins, including glutathione peroxidase (GPx) and thioredoxin reductase. In the context of trauma and critical illness, systemic inflammation and oxidative stress frequently deplete selenium reserves, compromising the body's antioxidant defenses. This deficiency exacerbates immune dysfunction, elevates the risk of multi-organ dysfunction syndrome, and increases susceptibility to infections and mortality. Observational studies have consistently shown that lower selenium levels correlate with poorer clinical outcomes, such as extended stays in intensive care units and higher mortality rates. Supplementation of selenium has demonstrated promise in restoring GPx activity, reducing oxidative stress markers, and supporting recovery, particularly in patients with pre-existing selenium deficiency. While the impact on mortality remains variable across clinical trials, early and targeted supplementation appears to be beneficial, especially when combined with other micronutrients like vitamins C and E or zinc. These combinations enhance the antioxidant response and tackle the complex oxidative pathways in critically ill and trauma patients. Importantly, the clinical benefits of selenium supplementation appear to be influenced by baseline selenium status, with patients exhibiting severe deficiency deriving the most pronounced improvements in oxidative stress markers, immune function, and recovery. This review highlights the critical importance of addressing selenium deficiency, advocating for personalized therapeutic strategies. However, further large-scale studies are essential to optimize dosing regimens, refine combination therapies, and validate selenium's therapeutic potential in trauma and critical care settings.

Oxazole-Based Ferroptosis Inhibitors with Promising Properties to Treat Central Nervous System Diseases

Ferroptosis plays an important role in the occurrence and development of many diseases, including neurodegenerative diseases. Thus, ferroptosis inhibitors able to cross the blood-brain barrier may have therapeutic potential. The best ferroptosis inhibitors so far are lipophilic radical trapping antioxidants (RTAs) that block lipid peroxidation in membranes. Several generations of ferrostatins have been synthesized, among which UAMC-3203 showed high potency in animal models with improved properties compared to ferrostatin-1. To further improve its pharmacokinetics properties, drug-likeness, and permeability, we modified UAMC-3203 by decreasing the size of the molecule and reducing its polarity by replacing the sulfonamide first by amide groups and subsequently by isosteric oxazoles. Herein, we present the design, synthesis, and biological evaluation of a novel series of oxazole RTAs with high potency, excellent oral bioavailability, and high concentrations in brain tissue.

Exploration of key genes associated with oxidative stress in polycystic ovary syndrome and experimental validation

Introduction

The current study demonstrated that oxidative stress (OS) is closely related to the pathogenesis of polycystic ovary syndrome (PCOS). However, there are numerous factors that lead to OS, therefore, identifying the key genes associated with PCOS that contribute to OS is crucial for elucidating the pathogenesis of PCOS and selecting appropriate treatment strategies.

Methods

Four datasets (GSE95728, GSE106724, GSE138572, and GSE145296) were downloaded from the gene expression omnibus (GEO) database. GSE95728 and GSE106724 were combined to identify differentially expressed genes (DEGs) in PCOS. weighted gene correlation network analysis (WGCNA) was used to screen key module genes associated with PCOS. Differentially expressed OS related genes (DE-OSRGs) associated with PCOS were obtained by overlapping DEGs, key module genes, and OSRGs. Subsequently, the optimal machine model was obtained to identify key genes by comparing the performance of the random forest model (RF), support vector machine model (SVM), and generalized linear model (GLM). The molecular networks were constructed to reveal the non-coding regulatory mechanisms of key genes based on GSE138572 and GSE145296. The Drug-Gene Interaction Database (DGIdb) was used to predict the potential therapeutic agents of key genes for PCOS. Finally, the expression of key OSRGs was validated by RT-PCR.

Results

In this study, 8 DE-OSRGs were identified. Based on the residuals and root mean square error of the three models, the best performance of RF was derived and 7 key genes (TNFSF10, CBL, IFNG, CP, CASP8, APOA1, and DDIT3) were identified. The GSEA enrichment analysis revealed that TNFSF10, CP, DDIT3, and INFG are all enriched in the NOD-like receptor signaling pathway and natural killer cell-mediated cytotoxicity pathways. The molecular regulatory network uncovered that both TNFSF10 and CBL are regulated by non-coding RNAs. Additionally, 70 potential therapeutic drugs for PCOS were predicted, with ibuprofen associated with DDIT3 and IFNG. RT-qPCR validation confirmed the expression trends of key genes IFNG, DDIT3, and APOA1 were consistent with the dataset, and the observed differences were statistically significant (P < 0.05).

Conclusion

The identification of seven key genes and molecular regulatory networks through bioinformatics analysis is of great significance for exploring the pathogenesis and therapeutic strategies of PCOS.

NINJ1 in Cell Death and Ferroptosis: Implications for Tumor Invasion and Metastasis

NINJ1 was initially recognized for its role in nerve regeneration and cellular adhesion. Subsequent studies have uncovered its participation in cancer progression, where NINJ1 regulates critical steps in tumor metastasis, such as cell migration and invasion. More recently, NINJ1 has emerged as a multifunctional protein mediating plasma membrane rupture (PMR) in several lytic cell death processes, including apoptosis, necroptosis, and pyroptosis. However, its role in ferroptosis-an iron-dependent form of lytic cell death characterized by lipid peroxidation-remained unclear until 2024. Ferroptosis is a tumor suppression mechanism that may be particularly relevant to detached and metastatic cancer cells. This review explores the role of NINJ1 in tumor invasion and metastasis, focusing on its regulation of ferroptosis via a non-canonical mechanism distinct from other cell deaths. We discuss the process of ferroptosis and its implications for cancer invasion and metastasis. Furthermore, we review recent studies highlighting the diverse roles of NINJ1 in ferroptosis regulation, including its canonical function in PMR and its non-canonical function of modulating intracellular levels of glutathione (GSH) and coenzyme A (CoA) via interaction with xCT anti-porter. Given that ferroptosis has been associated with tumor suppression, metastasis, the elimination of treatment-resistant cancer cells, and tumor dormancy, NINJ1's modulation of ferroptosis presents a promising therapeutic target for inhibiting metastasis. Understanding the dual role of NINJ1 in promoting or restraining ferroptosis depending on cellular context could open avenues for novel anti-cancer strategies to enhance ferroptotic vulnerability in metastatic tumors.

Interleukins-27 Aggravates Liver Injury by Impairing the Antimicrobial Response of Macrophages via the Promotion of Mitochondrial Dysfunction in the Context of Sepsis

Background and Aims: Plasma interleukin (IL)-27 is an important mediator of acute hepatic injury (AHI) associated with sepsis. Mitochondria contribute to the proper regulation of macrophage phagocytosis. In this study, we investigated the effect of IL-27 on mitochondrial function and the antimicrobial response of macrophages in sepsis-associated AHI. Methods: Wild-type (WT) and IL-27 receptor WSX-1 deficient (IL-27R-/-) mice underwent cecal ligation and puncture (CLP). The severity of hepatic injury, inflammatory cytokine levels, hepatic pyroptosis, and bacterial load in the liver and blood were assessed 24 h after CLP. In vitro, RAW264.7 cells and peritoneal macrophages were treated with lipopolysaccharide (LPS) and/or IL-27. The phagocytosis and killing functions of macrophages were detected. Mitochondrial function and mitophagy were detected using western blot, glutathione (GSH)/malondialdehyde (MDA) content measurement, fluorescence staining, and JC-1 staining in vivo and in vitro. After treatment with nicotinamide mononucleotide (NMN, NAD + precursor), a pharmacologic agent that improves mitochondrial function, the inflammatory response, hepatic injury, and hepatic pyroptosis were assessed. Results: IL-27R-/- mice exhibited a marked reduction in hepatic injury, pyroptosis (based on cleaved GSDMD and cleaved Caspases 1 protein levels), and systemic inflammation (based on serum IL-6, IL-10, and TNF-α levels) compared to WT mice following CLP. After CLP, mice lacking IL-27R displayed significantly higher bacterial clearance and greater local infection control. Subsequent studies demonstrated that IL-27 directly impaired the LPS-induced bacterial phagocytosis, killing capacity, and mitochondrial function of macrophages. Finally, enhanced mitochondrial function using NMN in vivo significantly alleviated pathological liver injury and inflammation. Conclusions: These findings indicated that IL-27 impairs the bacterial phagocytosis capacity of macrophages by aggravating mitochondrial dysfunction to aggravate AHI during sepsis.

Genome-wide association study reveals multiple loci for nociception and opioid consumption behaviors associated with heroin vulnerability in outbred rats

The increased prevalence of opioid use disorder (OUD) makes it imperative to disentangle the biological mechanisms contributing to individual differences in OUD vulnerability. OUD shows strong heritability, however genetic variants contributing to vulnerability remain poorly defined. We performed a genome-wide association study using over 850 male and female heterogeneous stock (HS) rats to identify genes underlying behaviors associated with OUD such as nociception, as well as heroin-taking, extinction and seeking behaviors. By using an animal model of OUD, we were able to identify genetic variants associated with distinct OUD behaviors while maintaining a uniform environment, an experimental design not easily achieved in humans. Furthermore, we used a novel non-linear network-based clustering approach to characterize rats based on OUD vulnerability to assess genetic variants associated with OUD susceptibility. Our findings confirm the heritability of several OUD-like behaviors, including OUD susceptibility. Additionally, several genetic variants associated with nociceptive threshold prior to heroin experience, heroin consumption, escalation of intake, and motivation to obtain heroin were identified. Tom1, a microglial component, was implicated for nociception. Several genes involved in dopaminergic signaling, neuroplasticity and substance use disorders, including Brwd1, Pcp4, Phb1l2 and Mmp15 were implicated for the heroin traits. Additionally, an OUD vulnerable phenotype was associated with genetic variants for consumption and break point, suggesting a specific genetic contribution for OUD-like traits contributing to vulnerability. Together, these findings identify novel genetic markers related to the susceptibility to OUD-relevant behaviors in HS rats.

Calling for a comprehensive risk assessment of selenium in drinking water

In the last two decades, research has elucidated that selenium, a trace element, has both nutritional and toxicological effects on human health, depending on its dose and chemical form. Recent animal, laboratory, and human studies have shown harmful effects of certain selenium species at specific exposure levels, prompting the need to reassess overall exposure to this element, including that occurring through drinking water, a primary source of inorganic selenium. Drinking water selenium standards worldwide are scarce and existing standards are inconsistent, likely because they have been informed by an incomplete and outdated assessment of the scientific evidence. Incorporating all the available human and laboratory evidence into a precautionary regulatory framework indicates that a drinking water limit of around 5 μg/L of selenium is needed to protect human health, i.e. with an uncertainty factor of 2 versus the lowest adverse effect level observed in human studies, and that higher values may pose unacceptable risks to humans. Despite the rarity of such high levels of selenium in underground and potable waters, coal mining and other sources of environmental pollution as well as geological factors may raise drinking water selenium content above a safe threshold, triggering the need to protect consumers, and to face challenging technological issues for selenium removal, currently under active investigation.

Bee Pollen Potential to Modulate Ferroptosis: Phytochemical Insights for Age-Related Diseases

Bee pollen (BP) is one of the richest known natural resources of micronutrients and bioactive phytochemicals. Some captivating bioactivities of BP compounds, although being largely investigated for the latter as individual molecules, remain very scarcely investigated or completely uninvestigated in bee pollen as a whole product. Among the most intriguing of these bioactivities, we identified ferroptosis as a major one. Ferroptosis, a recently discovered form of cell death (connecting oxidative stress and inflammation), is a complex pathophysiological process and one of the most crucial and perplexing events in current challenging human diseases such as cancer, neurodegeneration, and general aging diseases. Many BP compounds were found to intricately modulate ferroptosis depending on the cellular context by inducing this cell death mechanism in malignant cells and preventing it in non-malignant cells. Since research in both fields, i.e., BP and ferroptosis, is still recent, we deemed it necessary to undertake this review to figure out the extent of BP potential in modulating ferroptosis mechanisms. Our research proved that a wide range of BP compounds (polyphenols, phenolamides, carotenoids, vitamins, minerals, and others) substantially modulate diverse ferroptosis mechanisms. Accordingly, these phytochemicals and nutrients showed interesting potential in preclinical studies to lead to ferroptosis-mediated outcomes in important pathophysiological processes, including many aging-related disorders. One of the most paramount challenges that remain to be resolved is to determine how different BP compounds act on ferroptosis in different biological and pathophysiological contexts, either through synergistic or antagonistic behaviors. We hope that our current work constitutes a valuable incentive for future investigations in this promising and very relevant research avenue.

The association of selenium exposure with the odds of metabolic syndrome: a dose-response meta-analysis

BACKGROUND

Selenium is a key regulator of metabolic homeostasis. It has been proposed that exposure to selenium might be associated with metabolic syndrome (MetS). However, the results are contradictory. This meta-analysis was carried out to analyze the relationships between selenium levels in biological samples and odds of Mets.

METHODS

We searched Scopus and PubMed databases up until September 2024 to identify relevant studies. Odds ratio (OR) and 95% confidence interval was used to pool the data using a random effects model.

RESULTS

The meta-analysis encompassed 18 observational studies involving 21,481 participants. It found that higher selenium exposure was related to an elevated likelihood of MetS (OR = 1.30, 95% CI = 1.12-1.51), even after controlling for covariates, such as smoking, age, alcohol consumption, and physical activity. Heterogeneity was significant among the studies (I² = 88.9%, P = 0.001). While elevated serum selenium levels linked to a higher odds of MetS, no such relationship was observed for selenium in urine or toenails. Subgroup analyses indicated that this association was evident only in females (OR = 2.0, 95% CI = 1.17-1.43) and particularly pronounced in individuals aged ≥ 50 years. A dose-response relationship was identified, showing a 6% increase in MetS odds for each additional 10 µg/L of serum selenium, with the odds rising non-linearly when serum levels surpassed 80 µg/L.

CONCLUSIONS

This study suggests that selenium may associated with the odds of MetS, following a dose-response relationship.

Attenuated growth factor signaling during cell death initiation sensitizes membranes towards peroxidation

Cell death programs such as apoptosis and ferroptosis are associated with aberrant redox homeostasis linked to lipid metabolism and membrane function. Evidence for cross-talk between these programs is emerging. Here, we show that cytotoxic stress channels polyunsaturated fatty acids via lysophospholipid acyltransferase 12 into phospholipids that become susceptible to peroxidation under additional redox stress. This reprogramming is associated with altered acyl-CoA synthetase isoenzyme expression and caused by a decrease in growth factor receptor tyrosine kinase (RTK)-phosphatidylinositol-3-kinase signaling, resulting in suppressed fatty acid biosynthesis, for specific stressors via impaired Akt-SREBP1 activation. The reduced availability of de novo synthesized fatty acids favors the channeling of polyunsaturated fatty acids into phospholipids. Growth factor withdrawal by serum starvation mimics this phenotype, whereas RTK ligands counteract it. We conclude that attenuated RTK signaling during cell death initiation increases cells' susceptibility to oxidative membrane damage at the interface of apoptosis and alternative cell death programs.

Regulation of pattern recognition receptor signaling by palmitoylation

Pattern recognition receptors (PRRs), consisting of Toll-like receptors, RIG-I-like receptors, cytosolic DNA sensors, and NOD-like receptors, sense exogenous pathogenic molecules and endogenous damage signals to maintain physiological homeostasis. Upon activation, PRRs stimulate the sensitization of nuclear factor κB, mitogen-activated protein kinase, TANK-binding kinase 1-interferon (IFN) regulatory factor, and inflammasome signaling pathways to produce inflammatory factors and IFNs to activate Janus kinase/signal transducer and activator of transcription signaling pathways, resulting in anti-infection, antitumor, and other specific immune responses. Palmitoylation is a crucial type of post-translational modification that reversibly alters the localization, stability, and biological activity of target molecules. Here, we discuss the available knowledge on the biological roles and underlying mechanisms linked to protein palmitoylation in modulating PRRs and their downstream signaling pathways under physiological and pathological conditions. Moreover, recent advances in the use of palmitoylation as an attractive therapeutic target for disorders caused by the dysregulation of PRRs were summarized.

The family of glutathione peroxidase proteins and their role against biotic stress in plants: a systematic review

Introduction

Glutathione peroxidases (GPXs) are extensively studied for their indispensable roles in eliminating reactive oxygen species by catalyzing the reduction of hydrogen peroxide or lipid peroxides to prevent cell damage. However, knowledge of GPXs in plants still has many gaps to be filled. Thus, we present the first systematic review (SR) aimed at examining the function of GPXs and their protective role against cell death in plants subjected to biotic stress.

Methods

To guide the SR and avoid bias, a protocol was developed that contained inclusion and exclusion criteria based on PRISMA guidelines. Three databases (PubMed, Science Direct, and Springer) were used to identify relevant studies for this research were selected.

Results

A total of 28 articles related to the proposed objective. The results highlight the importance of GPXs in plant defense against biotic stress, including their role in protecting against cell death, similar to the anti-apoptotic GPXs in animals. Data from gene expression and protein accumulation studies in plants under various biotic stresses reveal that GPXs can both increase resistance and susceptibility to pathogens. In addition to their antioxidant functions, GPXs act as sensors and transmitters of H2O2 signals, integrating with the ABA signaling pathway during stress.

Discussion

These findings show that GPXs delay senescence or reinforce physical barriers, thereby modulating resistance or susceptibility to pathogens. Additionally, their functions are linked to their cellular localization, which demonstrates an evolutionary relationship between the studied isoforms and their role in plant defense. This information broadens the understanding of molecular strategies involving GPX isoforms and provides a foundation for discussions and actions aimed at controlling necrotrophic and/or hemibiotrophic pathogens.

KAT8 catalyzes the acetylation of SEPP1 at lysine 247/249 and modulates the activity of CD8+ T cells via LRP8 to promote anti-tumor immunity in pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) remains one of the most lethal malignancies with unfavorable prognosis globally. Bioinformatics analysis predicted that SEPP1 was low expressed in PC and related to tumor immune microenvironment, but its biological function was still unclear.

METHODS

PC xenograft and liver metastasis mouse models, as well as PC cell-MDSCs co-culture system, were established for in vivo and in vitro studies, respectively. The expression and localization of key molecules were detected by qRT-PCR, western blot, immunohistochemistry and immunofluorescence. Flow cytometry was employed to assess the abundance of immune cells and cell apoptosis. The interactions among KAT8, SEPP1 and LRP8 were detected by co-IP. Cell viability, migration and invasion were monitored by CCK-8 and transwell assays.

RESULTS

SEPP1 was downregulated in pancreatic tumors, and it was positively correlated with the abundance of CD8+ T cells. In vivo overexpression of SEPP1 impaired PC tumor growth and liver metastasis via modulating the abundance of CD8+ T cell and MDSCs. KAT8 upregulated SEPP1 transcription and protein level via catalyzing the acetylation at K247/249 on SEPP1, and SEPP1 impaired MDSCs survival via its receptor LRP8, thus regulating CD8+ T cell-mediated immune responses in PC. In vivo studies further revealed that SEPP1 recombinant protein enhanced the efficacy of anti-PD-1 therapy in PC xenograft mouse model.

CONCLUSION

KAT8 catalyzed the acetylation of SEPP1 at K247/249 and modulated the activity of CD8+ T cells via LRP8 to promote anti-tumor immunity in PC.

Unraveling AURKB as a potential therapeutic target in pulmonary hypertension using integrated transcriptomic analysis and pre-clinical studies

Despite advances in treatment, the prognosis for patients with pulmonary arterial hypertension (PAH) remains dismal, highlighting the need for further therapeutic advances. By using RNA sequencing on pulmonary artery smooth muscle cells (PASMCs), functional enrichment, and connectivity map analyses, we identify Aurora kinase B (AURKB) as a candidate therapeutic target. We show that AURKB inhibition blocks cell cycle progression and reverses the gene signature of PAH-PASMCs. We also report that PAH-PASMCs that escape apoptosis acquire a senescence-associated secretory phenotype. In vivo, AURKB inhibition using barasertib improves hemodynamics in two preclinical models of established PAH by attenuating pulmonary vascular remodeling. A therapeutic effect is also observed in human precision-cut lung slices. Finally, we demonstrate that the combination of barasertib with a p21 attenuator is more effective in reducing vascular remodeling than either drug alone. These findings provide insight into strategies for therapeutic manipulation.

Origins of Ultrasensitivity and Complex Signaling Dynamics of Cellular Hydrogen Peroxide and Peroxiredoxin

Hydrogen peroxide (H2O2) plays a crucial role in cell signaling in response to physiological and environmental perturbations. H2O2 can oxidize typical 2-Cys peroxiredoxin (PRX) first into a sulfenic acid, which resolves into a disulfide that can be reduced by thioredoxin (TRX)/TRX reductase (TR). At high levels, H2O2 can also hyperoxidize sulfenylated PRX into a sulfinic acid that can be reduced by sulfiredoxin (SRX). Therefore, PRX, TRX, TR, and SRX (abbreviated as PTRS system here) constitute the coupled sulfenylation and sulfinylation cycle (CSSC), where certain oxidized PRX and TRX forms also function as redox signaling intermediates. Earlier studies have revealed that the PTRS system is capable of rich signaling dynamics, including linearity, ultrasensitivity/switch-like response, nonmonotonicity, circadian oscillation, and possibly, bistability. However, the origins of ultrasensitivity, which is fundamentally required for redox signal amplification, have not been adequately characterized, and their roles in enabling complex nonlinear dynamics of the PTRS system remain to be determined. Through in-depth mathematical modeling analyses, here we revealed multiple sources of ultrasensitivity that are intrinsic to the CSSC, including zero-order kinetic cycles, multistep H2O2 signaling, and a mechanism arising from diminished H2O2 removal at high PRX hyperoxidation state. The CSSC, structurally a positive feedback loop, is capable of bistability under certain parameter conditions, which requires embedding multiple sources of ultrasensitivity identified. Forming a negative feedback loop with cytosolic SRX as previously observed in energetically active cells, the mitochondrial PTRS system (where PRX3 is expressed) can produce sustained circadian oscillations through supercritical Hopf bifurcations. In conclusion, our study provided novel quantitative insights into the dynamical complexity of the PTRS system and improved appreciation of intracellular redox signaling.

Improvement of β-Cell Function After Switching From DPP-4 Inhibitors to Oral Semaglutide: SWITCH-SEMA2 Post Hoc Analysis

CONTEXT

Whether continuation of dipeptidyl peptidase-4 inhibitors (DPP-4is) or switching to oral semaglutide is more beneficial for β-cell function is unclear.

OBJECTIVE

To assess the efficacy of switching from DPP-4is to oral semaglutide for β-cell function compared with DPP-4i continuation.

METHODS

Post hoc analysis of SWITCH-SEMA 2, a multicenter prospective randomized controlled trial on the switch to oral semaglutide vs DPP-4i continuation without dose adjustment for 24 weeks in subjects with type 2 diabetes treated with DPP-4is, was conducted. Changes in markers for glucose metabolism, including homeostatic model assessment (HOMA2) scores and disposition index (DI), were compared between the groups.

RESULTS

A total of 146 subjects (semaglutide group, 69; DPP-4i group, 77) were analyzed. In the semaglutide group, glycemic control, liver enzyme deviations, and lipid profiles improved after 24 weeks. Regarding indices for β-cell function, changes in HOMA2-β as well as DI, reflecting the ability of β-cells to compensate for insulin resistance, were significantly higher in the semaglutide group compared with the DPP-4i group (mean change, +10.4 vs +0.6 in HOMA2-β [P = .001] and +0.09 vs 0.0 in DI [P < .001]). Improvement in DI in the semaglutide group was correlated significantly to changes in body mass index (BMI), HbA1c, and fatty liver index reflecting liver steatosis. Multiple linear regression analysis revealed that dose of semaglutide (≥ 7 mg/day), reduction in fatty liver index, and metformin nonuse were independently associated with improvement of DI.

CONCLUSION

Switching to oral semaglutide ameliorated β-cell function compared with DPP-4is, presumably via tissue-to-tissue crosstalk between liver and β-cells.

Nanoscale visualization of the anti-tumor effect of a plasma-activated Ringer's lactate solution

Plasma-activated Ringer's lactate solutions (PALs), which are Ringer's lactate solutions treated with non-thermal atmospheric-pressure plasma, have an anti-tumor effect and can be used for chemotherapy. As the anti-tumor effect of the PAL is influenced by the cell-treatment time, it is necessary to monitor the structural changes of the cell surface with non-invasive, nanoscale, and time-lapse imaging to understand the anti-tumor effect. In this study, to characterize the anti-tumor effect of the PAL, we used scanning ion conductance microscopy (SICM), using glass nanopipettes as probes, to visualize the structural changes of the cell surface. SICM time-lapse topographic imaging visualized a decrease in the movement of lamellipodia in normal cells and cancer cells after the PAL treatment. Furthermore, in normal cells, protrusive structures were observed on the cell surface. Time-lapse imaging using SICM allowed us to characterize the differences in the morphological changes between the normal and cancer cells upon exposure to the PAL.

Downregulation of the SREBP pathways and disruption of redox status by 25-hydroxycholesterol predispose cells to ferroptosis

Enzymatically formed side-chain oxysterols function as signaling molecules regulating cholesterol homeostasis and act as intermediates in the biosynthesis of bile acids. In addition to these physiological functions, an imbalance in oxysterol homeostasis has been implicated in pathophysiology. Cholesterol 25-hydroxylase (CH25H) and its product 25-hydroxycholesterol (25-OHC), also formed by autoxidation, are associated with amyotrophic lateral sclerosis. However, the effects of 25-OHC on cell viability in glial cells remain unclear. This study demonstrates that 25-OHC induces ferroptosis, an iron-dependent programmed cell death, in mouse Schwann IMS32 cells. Mechanistically, 25-OHC suppressed the expression of selenoprotein glutathione peroxidase 4 (GPX4) at both the transcriptional and translational levels by inhibiting the processing of sterol regulatory element-binding proteins (SREBPs). In addition, 25-OHC upregulated the expression of NADH-cytochrome b5 reductase 1 (CYB5R1) and NADPH-cytochrome P450 reductase (POR), enzymes that promote lipid peroxidation. We further found that 25-OHC increases the expression of glutathione-specific gamma-glutamylcyclotransferase 1 (CHAC1) and decreases glutathione levels. Importantly, non-cytotoxic concentrations of 25-OHC enhanced cellular sensitivity to ferroptosis inducers by downregulating GPX4 expression. These findings reveal a multifaceted approach whereby 25-OHC induces ferroptosis through SREBP pathway suppression and redox imbalance in mouse Schwann IMS32 cells.

Double-edged sword effect of GPX4 in skin homeostasis and diseases

Glutathione peroxidase 4 (GPX4) is a crucial antioxidant enzyme that plays a vital role in protecting cells from oxidative damage and lipid peroxidation. In the context of skin diseases, GPX4 serves as a key regulator of oxidative stress and inflammation, both of which are significant features of various skin conditions. By preventing lipid peroxidation and maintaining membrane integrity, GPX4 acts as a safeguard against cell death pathways, particularly ferroptosis, in skin diseases. Dysregulation of GPX4 in conditions such as dermatitis, psoriasis, and skin cancer is linked to heightened oxidative stress, inflammation, and tissue damage. Understanding the role of GPX4 and its intricate interactions in skin disease pathogenesis can aid in more effectively targeting oxidative stress and inflammation, leading to promising therapeutic interventions. This review summarizes the role of GPX4 in maintaining skin homeostasis and its involvement in disease, proposing strategies to target GPX4, including its post-translational modifications. Investigate the precise mechanism through which GPX4 influences the onset of skin diseases, and utilize GPX4 agonists or inhibitors as potential treatments.

Unveiling the Role of Selenium in Child Development: Impacts on Growth, Neurodevelopment and Immunity

Selenium (Se) is a vital trace element for children, playing a crucial role in numerous physiological processes, including antioxidant defense, immune regulation, thyroid function, and bone metabolism. Emerging evidence highlights its potential impact on child development and growth while also underscoring the complexity of its mechanisms and the global variations in Se intake. The aim of this review is to comprehensively elucidate the significance of Se in various biological processes within the human body, with a focus on its role in child development and growth; its biochemical effects on the nervous system, thyroid function, immune system, and bone tissue; and the implications of Se deficiency and toxicity. This review integrates findings from experimental models, epidemiological studies, and clinical trials to explore Se's role in neurodevelopment, growth regulation, and immune competence in children. Selenoproteins, which regulate oxidative stress and thyroid hormone and bone metabolism, are essential for normal growth and cognitive development in children. Se deficiency and toxicity has been linked to impaired immune function, growth retardation, and decreased immune function. The findings underscore Se's influence on various biological pathways that are critical for healthy child development and its broader importance for child health. Public health strategies aimed at optimizing selenium intake may play a pivotal role in improving pediatric health outcomes worldwide.

A clinical drug candidate that triggers non-apoptotic cancer cell death

Small molecules that induce non-apoptotic cell death are of fundamental mechanistic interest and may be useful to treat certain cancers. Here, we report that tegavivint, a drug candidate undergoing human clinical trials, can activate a unique mechanism of non-apoptotic cell death in sarcomas and other cancer cells. This lethal mechanism is distinct from ferroptosis, necroptosis and pyroptosis and requires the lipid metabolic enzyme trans-2,3-enoyl-CoA reductase (TECR). TECR is canonically involved in the synthesis of very long chain fatty acids but appears to promote non-apoptotic cell death in response to CIL56 and tegavivint via the synthesis of the saturated long-chain fatty acid palmitate. These findings outline a lipid-dependent non-apoptotic cell death mechanism that can be induced by a drug candidate currently being tested in humans.

The Cross-Talk Between the Peripheral and Brain Cholesterol Metabolisms

Cholesterol is an essential element for the development and normal function of the central nervous system. While peripheral cholesterol is influenced by liver metabolism and diet, brain cholesterol metabolism takes place in an isolated system due to the impermeability of the blood-brain barrier (BBB). However, cross-talk occurs between the brain and periphery, specifically through metabolites such as oxysterols that play key roles in regulating cholesterol balance. Several neurodegenerative conditions such as Alzheimer's disease or Parkinson's disease are considered to be affected by the loss of this balance. Also, the treatment of hypercholesterolemia needs to consider these discrete interferences between brain and peripheral cholesterol and the possible implications of each therapeutic approach. This is particularly important because of 27-hydroxycholesterol and 24-hydroxycholesterol, which can cross the BBB and are involved in cholesterol metabolism. This paper examines the metabolic pathways of cholesterol metabolism in the brain and periphery and focuses on the complex cross-talk between these metabolisms. Also, we emphasize the regulatory role of the BBB and the need for an integrated approach to cholesterol management.

Role of ferroptosis in atrial fibrillation: a review

Cardiovascular disease remains the leading cause of mortality, with atrial fibrillation emerging as one of the most common conditions encountered in clinical practice. However, its underlying mechanisms remain poorly understood, prompting ongoing research. Ferroptosis, a recently discovered form of regulated cell death characterized by lipid peroxidation and disrupted cellular redox balance leading to cell death due to iron overload, has attracted significant attention. Since its identification, ferroptosis has been extensively studied in various contexts, including cancer, stroke, myocardial ischemia/reperfusion injury, and heart failure. Growing evidence suggests that ferroptosis may also play a critical role in the onset and progression of atrial fibrillation, though research in this area is still limited. This article provides a concise overview of the potential mechanisms by which ferroptosis may contribute to the pathogenesis of atrial fibrillation.

Selenium and Episodic Memory: The Moderating Role of Apolipoprotein E ε4

Background: Selenium (Se), a vital trace element, plays a neuroprotective role by mitigating oxidative stress through selenoproteins and regulating metal balance. The apolipoprotein E ε4 allele (APOE4), a significant genetic risk factor for Alzheimer's disease (AD), has been linked to reduced Se levels and weakened antioxidant capacity. This research explores the association between serum Se concentrations and cognitive performance, with an emphasis on how APOE4 status influences this relationship. Methods: This study included 196 older adults from community and memory clinic settings, who underwent assessments for episodic memory, global cognition, and non-memory functions using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery, with serum selenium levels analyzed via inductively coupled plasma-mass spectrometry (ICP-MS) and APOE genotyping conducted to determine allele status. Results: Higher serum Se levels were associated with better episodic memory score (EMS) (B = 0.065, 95% CI = 0.020-0.110, p = 0.005) and CERAD total score (TS) (B = 0.119, 95% CI = 0.046-0.193, p = 0.002). However, the interaction between Se and APOE4 status significantly affected EMS (B = -0.074, 95% CI = -0.109 to -0.039, p < 0.001), with significant benefits observed in APOE4-negative participants. Conclusions: This study highlights the genotype-specific impact of Se on cognitive health, emphasizing the need for personalized nutritional interventions targeting Se levels, particularly for APOE4-negative individuals. Future research should further elucidate the mechanisms of Se's effects and assess its therapeutic potential in aging populations.

Placental Ferroptosis May Be Involved in Prenatal Arsenic Exposure Induced Cognitive Impairment in Offspring

The association between prenatal arsenic (As) exposure and offspring's cognition is still unclear, and the underlying etiology has also not been elucidated. Based on the Ma'anshan Birth Cohort (MABC) study in China, 1814 mother-child pairs were included in this study, and the association of As levels in cord serum with preschoolers' intelligence scores was explored. To validate the results from population study, in vivo models were adopted to observe the association between prenatal As exposure and spatial learning and memory abilities of mice offsprings. The As-exposure induced ferroptosis in the placenta of human beings as well as C57BL/6 J mice and HTR-8/SVneo cells was explored in order to clarify the potential cause of impairment of offspring's cognition related to As exposure, respectively. In the population study, we observed a significant inverse association between natural logarithm transformed (ln) As levels and preschoolers' intelligence scores, especially for the fluid reasoning index (FRI) [(β (95%CI): - 1.07 (- 1.98, - 0.16)] and working memory index (WMI) [β (95%CI): - 1.51 (- 2.76, - 0.25)]. Meanwhile, the data from in vivo models revealed that the learning and memory abilities of offspring mice decreased after prenatal As exposure. The occurrence of ferroptosis-like characteristics in the placenta and HTR-8/SVneo cells after As exposure was observed, accompanying with evident oxidative stress, iron accumulation, mitochondrial damage, and decreased protein levels of GPX4, xCT, and FTH1 (or FPN1). Notably, the ferroptosis-like alterations induced by NaAsO2 can be effectively alleviated by N-acetylcysteine (NAC) and ferrostatin-1 (Fer-1) treatment in HTR-8/SVneo cells, respectively. In conclusion, prenatal As exposure associates with impairment of offspring's cognition, and placental ferroptosis may be involved in the association. Further studies are needed to confirm the findings.

Nanoization of Technical Pesticides: Facile and Smart Pesticide Nanocapsules Directly Encapsulated through "On Site" Metal-Polyphenol Coordination Assembly for Improved Efficacy and Biosafety

Facile pesticide nanocapsules were successfully prepared by directly encapsulating the antisolvent precipitation of pesticides through instantaneous "on site" coordination assembly of tannic acid and Fe3+, avoiding tedious preparation, time consumption, and large amounts of organic solvents. The pesticide nanocapsules showed excellent resistance to ultraviolet photolysis and rainwater washing owing to the nanocapsule walls. The smart pesticide nanocapsules exhibited the controlled release of pesticides under multidimensional stimuli, such as acidic/alkaline pH, glutathione, H2O2, phytic acid, laccase, tannase, and sunlight, which were related to the physiological and natural environments of crops, pests, and pathogens. The tebuconazole nanocapsules not only enhanced the fungicidal activity against Fusarium graminearum and effective control efficacy in wheat powdery mildew through foliar spray and seed coating, but also improved the biosafety of target plant growth and nontarget organisms. The facile, smart, efficient, safe, and green pesticide nanocapsules using the universal strategy have broad application prospects in ecoagriculture.

Intricating connections: the role of ferroptosis in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic inflammatory and autoimmune disease with multiple tissue damage. However, the pathology remains elusive, and effective treatments are lacking. Multiple types of programmed cell death (PCD) implicated in SLE progression have recently been identified. Although ferroptosis, an iron-dependent form of cell death, has numerous pathophysiological features similar to those of SLE, such as intracellular iron accumulation, mitochondrial dysfunction, lipid metabolism disorders and concentration of damage associated-molecular patterns (DAMPs), only a few reports have demonstrated that ferroptosis is involved in SLE progression and that the role of ferroptosis in SLE pathogenesis continues to be neglected. Therefore, this review elucidates the potential intricate relationship between SLE and ferroptosis to provide a reliable theoretical basis for further research on ferroptosis in the pathogenesis of SLE.

Lipid peroxidation and sarcopenia: molecular mechanisms and potential therapeutic approaches

Sarcopenia is an age-related condition characterized by the progressive loss of skeletal muscle mass and strength. With the global aging population, its incidence is rapidly increasing. Lipid peroxidation is a critical biochemical process that generates reactive oxygen species (ROS), leading to the destruction of muscle cell structure and function. It plays a pivotal role in the onset and progression of sarcopenia. This review summarizes the mechanisms by which lipid peroxidation contributes to sarcopenia, with a focus on its regulatory effects on cell membrane damage, mitochondrial dysfunction, and cell death. In addition, we discuss the protective role of antioxidant factors such as GPX4 (glutathione peroxidase 4) and antioxidant peptides like SS peptides in mitigating lipid peroxidation and delaying the progression of sarcopenia. Finally, the potential of various strategies, including natural compounds, supplements, natural extracts, and lifestyle interventions, in inhibiting lipid peroxidation and promoting muscle health is explored.

Development of a Synthetic Platform for Ent-Pimaranes Reveals their Potential as Novel Non-Redox Active Ferroptosis Inhibitors

We present a comprehensive account on the evolution of a synthetic platform for a subfamily of ent-pimaranes. For the most complex member, norflickinflimiod C, five distinct strategies relying on either cationic or radical polyene cyclizations to construct the requisite tricyclic carbon scaffold were explored. Insights from early and late stage oxidative and reductive dearomatization studies ultimately led to a mild, rhodium-catalyzed arene hydrogenation for the final synthetic route. A Sharpless asymmetric dihydroxylation was found to be suitable to render the platform enantioselective and diversification of a late-stage key intermediate culminated in the total synthesis of eight ent-pimaranes in 11-16 steps. These compounds were found to inhibit the formation of pro-inflammatory leukotrienes and other 5-lipoxygenase products. Notably, three ent-pimaranes exhibited low micromolar, non-redox active ferroptosis inhibition with remarkable structural specificity.

Homeostasis and metabolism of iron and other metal ions in neurodegenerative diseases

As essential micronutrients, metal ions such as iron, manganese, copper, and zinc, are required for a wide range of physiological processes in the brain. However, an imbalance in metal ions, whether excessive or insufficient, is detrimental and can contribute to neuronal death through oxidative stress, ferroptosis, cuproptosis, cell senescence, or neuroinflammation. These processes have been found to be involved in the pathological mechanisms of neurodegenerative diseases. In this review, the research history and milestone events of studying metal ions, including iron, manganese, copper, and zinc in neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD), will be introduced. Then, the upstream regulators, downstream effector, and crosstalk of mental ions under both physiologic and pathologic conditions will be summarized. Finally, the therapeutic effects of metal ion chelators, such as clioquinol, quercetin, curcumin, coumarin, and their derivatives for the treatment of neurodegenerative diseases will be discussed. Additionally, the promising results and limitations observed in clinical trials of these metal ion chelators will also be addressed. This review will not only provide a comprehensive understanding of the role of metal ions in disease development but also offer perspectives on their modulation for the prevention or treatment of neurodegenerative diseases.

Selenoproteins: Zoom-In to Their Metal-Binding Properties in Neurodegenerative Diseases

Selenoproteins contain selenium (Se), which is included in the 21st proteinogenic amino acid selenocysteine (Sec). Selenium (Se) is an essential trace element that exerts its biological actions mainly through selenoproteins. Selenoproteins have crucial roles in maintaining healthy brain activity. At the same time, brain-function-associated selenoproteins may also be involved in neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The selenoproteins GPx4 (glutathione peroxidase 4), GPx1 (glutathione peroxidase 1), SELENOP (selenoprotein P), SELENOK (selenoprotein K), SELENOS (selenoprotein S), SELENOW (selenoprotein W), and SELENOT (selenoprotein T) are highly expressed, specifically in AD-related brain regions being closely correlated to brain function. Only a few selenoproteins, mentioned above (especially SELENOP), can bind transition and heavy metals. Metal ion homeostasis accomplishes the vital physiological function of the brain. Dyshomeostasis of these metals induces and entertains neurodegenerative diseases. In this review, we described some of the proposed and established mechanisms underlying the actions and properties of the above-mentioned selenoproteins having the characteristic feature of binding transition or heavy metals.

Heavy Chalcogen Properties of Sulfur and Selenium Enhance Nucleic Acid-Based Therapeutics

The Group 16 elements of the periodic table have a characteristic valence shell configuration instrumental to their chemical properties and reactivities. The electrostatic potentials of these so-called chalcogens have been exploited in the design of materials that require the efficient passage of electrons including supermagnets, photocatalytic dyes, and solar panels. Likewise, the incorporation of the heavy chalcogen selenium into organic frameworks has been shown to increase the reactivities of double bonds and heterocyclic rings, while its interactions with aromatic side chains in the hydrophobic core of proteins via selenomethionine impart a stabilizing effect. Typically present in the active site, the hypervalence of selenocysteine enables it to further stabilize the folded protein and mediate electron transfer. Selenium's native occurrence in bacterial tRNA maintains base pair fidelity, most notably during oxidative stress, through its electronic and steric effects. Such native modifications at the positions 2 and 5 of uridine render these sites relevant in the design of RNA-based therapeutics. Innocuous selenium substitution for oxygen in the former and the standard methods of selenium-derivatized oligonucleotide synthesis and detection have led to the establishment of a novel class of therapeutics. In this review, we summarize some progress in this area.

Intra-host variability of SARS-CoV-2: Patterns, causes and impact on COVID-19

Intra-host viral variability is related to pathogenicity, persistence, drug resistance, and the emergence of new clades. This work reviews the large amount of data on SARS-CoV-2 intra-host variability accumulated to date, addressing known and potential implications in COVID-19 and the emergence of VOCs and lineage-defining mutations. Topics covered include the distribution of intra-host polymorphisms across the genome, the corresponding mutational signatures, their patterns of emergence and extinction throughout infection, and the processes governing their abundance, frequency, and type (synonymous, nonsynonymous, indels, nonsense). Besides, evidence is reviewed that the virus can replicate and mutate in isolation at different anatomical compartments, which may imply that what we have learned from respiratory samples could be part of a broader picture.

Differential effect of cerium nanoparticles on the viability, redox-status and Ca2+-signaling system of cancer cells of various origins

The present study aims to understand the molecular mechanism underlying the therapeutic effect of cerium nanoparticles (CeNPs) in oncology. Cancer cells were treated with different concentrations of pure nanocerium of different sizes synthesized by laser ablation. Due to the not insignificant influence of surface defects and oxygen species on the ROS-modulating properties of cerium nanoparticles, the nanoparticles were not coated with surfactants or organic molecules during synthesis, which could potentially inhibit a number of pro-oxidative effects. Reactive oxygen species (ROS) production, expression of genes encoding redox-status proteins, selenoproteins and proteins regulating cell death and endoplasmic reticulum stress (ER-stress) were investigated as indicators of the molecular mechanism of cancer cell death. Studies were conducted on the effects of cerium nanoparticles on the Ca2+ signaling system of cancer cells of different origins. Mouse fibroblasts (L-929 cell line) were used as non-cancerous ("normal") cells for which a whole series of experiments were performed, and a comparative analysis of the effects of nanoceria. It was found that 75 nm-sized cerium nanoparticles did not affect the redox-status and ROS production of cancer cells. In fibroblast cells, however, this nanoparticle diameter led to a deterioration of the cellular redox status and ROS production in a wide range of nanoparticle concentrations. Larger nanoparticles (100 nm-sized and 160 nm-sized), on the other hand, showed a different effect on cancer cells of different origins. In mouse fibroblast L-929 cells, however, 100 nm-sized or 160 nm-sized CeNPs acted in a high concentration range to disrupt mitochondrial membrane potential and activate early apoptosis. High concentrations of CeNPs were required to increase ROS production, reduce redox-status and induce apoptosis in human A-172 glioblastoma cells compared to the hepatocellular carcinoma cell line HepG2 and the breast cancer cell line MCF-7. In the A-172 glioblastoma cells, ER-stress was also not activated and their Ca2+ signaling system was activated by a significantly higher concentration of CeNPs, which could also contribute to the formation of tolerance of this cancer cell line to nanoceria. The Ca2+ signaling system of mouse fibroblasts was found to be highly sensitive to activation by nanoceria and the cells produced Ca2+ signals with higher amplitude compared to A-172 and MCF-7 cells.

Unraveling the Link: Mendelian Randomization Reveals Causal Relationship Between Selenium and Metabolic Syndrome

Observational studies have linked selenium and metabolic syndrome (MetS), but the causality remains unclear. Therefore, this study intends to determine the causal relationship between selenium and the risk of MetS and its component features [body mass index (BMI), waist circumference adjusted for BMI (WCadjBMI), triglycerides (TC), HDL-cholesterol (HDL-C), fasting blood glucose (FBG), fasting blood insulin (FBI), systolic blood pressure (SBP), and diastolic blood pressure (DBP)]. This study was designed as the two-sample Mendelian randomization (MR), and genetic variants were obtained from the genome-wide association studies. The inverse variance weighted (IVW) was applied as the primary method, and the MR-Egger, weighted median, and MR-PRESSO were supplemented to assess its robustness. The Bonferroni method was used to correct p-values for multiple tests. Genetically incremented selenium level was related to higher odds ratios of developing the MetS (OR = 1.054, 95% CI = 1.016-1.094, p = 0.0049). As for components, significant causal links were identified between selenium and BMI (β = 0.015, p = 1.321 × 10-5), WCadjBMI (β = 0.033, p = 2.352 × 10-4), HDL-C (β = -0.036, p = 1.352 × 10-8), FBG (β = 0.028, p = 0.001), and FBI (β = 0.028, p = 0.002). No significant association was discovered for SBP (β = -0.076, p = 0.218) and DBP (β = 0.054, p = 0.227). These results were generally supported by the weighted median and MR-PRESSO methods. Our study provided evidence of the causal effect of selenium on MetS risk from the genetic perspective in the European population, and further investigation across diverse populations was warranted.