Ferroptosis in sepsis: The mechanism, the role and the therapeutic potential

Ferroptosis targeting offers a therapeutic target for septic cardiomyopathy

Sepsis-induced cardiac dysfunction, usually termed sepsis-induced cardiomyopathy or septic cardiomyopathy(SCM), is developed in approximately 70 % of the patients with sepsis, making it is a major concern for sepsis patients. However, the pathogenesis of SCM remain incompletely understood. Ferroptosis, a newly identified mechanism of regulated cell death, characterized by a decline in antioxidant capacity, iron accumulation, and lipid peroxidation(LPO), is involved in sepsis and SCM. Moreover, ferroptosis inhibitors confer a novel therapeutic regimen in SCM. In this Review, we first summarizes the core mechanism of ferroptosis, with an emphasis on how best to interpret ferroptosis leads to the genesis of SCM. We then highlights our focus on the emerging different types of therapeutic ferroptosis inhibitors and summarizes their pharmacological beneficial effect to treat SCM. This review highlights a novel potential therapeutic strategy for SCM by pharmacologically inhibiting ferroptosis.

PFOS exposure impairs porcine oocyte maturation and embryo development via mitochondria-dependent ferroptosis

Perfluorooctane sulfonate (PFOS) is a widely utilized chemical known for its exceptional environmental stability over extended periods, its significant potential to bioaccumulate in living organisms, and its considerable risks to both health and the environment. Several studies have suggested that PFOS may pose reproductive risks in mammals; however, the exact mechanisms driving these effects are not well understood. In this study, we explored the possible mechanisms by which PFOS toxicity affects the maturation of mammalian oocytes and the embryonic development employing porcine oocytes as a model system. SMART-seq results suggested that PFOS may affect oocyte maturation through mechanisms involving ferroptosis, autophagy, and alterations in membrane structure. Our results suggest that PFOS exposure adversely affects mitochondrial function and structure, thereby influencing peroxisome biogenesis and contributing to oxidative stress. Most importantly, we found that exposure to PFOS significantly elevated Fe2+ levels, an indicator associated with ferroptosis in oocytes. Furthermore, malondialdehyde (MDA) levels in the PFOS group were significantly higher than those in the control group. Additionally, the mRNA expression levels of PCBP1 and PCBP2, which are related to ferroptosis, as well as the expression level of P53, were significantly reduced in the PFOS group. Overall, exposure to PFOS in vitro results in mitochondrial damage in porcine oocytes, which induces lipid peroxidation and subsequently leads to the occurrence of ferroptosis.

Extracellular vesicle-packaged GBP2 from macrophages aggravates sepsis-induced acute lung injury by promoting ferroptosis in pulmonary vascular endothelial cells

Macrophages play a critical role in the development of sepsis-induced acute lung injury (si-ALI), with extracellular vesicles (EVs) acting as crucial mediators. However, the effects and mechanisms of macrophage-derived EVs on si-ALI remain unclear. This study demonstrated that macrophage-derived EVs induce endothelial ferroptosis and barrier disruption during sepsis. Through proteomic sequencing and reanalysis of transcriptomic and single-cell sequencing data, guanylate-binding protein 2 (GBP2) was identified as a key EV molecule. Elevated GBP2 expression was observed in EVs and monocytes from the peripheral blood of sepsis patients, in LPS-stimulated THP-1 and RAW264.7 cells and their secreted EVs, and in macrophages within the lungs of CLP mice. Additionally, GBP2 expression in EVs showed a positive correlation with vascular barrier injury biomarkers, including ANGPT2, Syndecan-1, and sTM. Modulating GBP2 levels in macrophage-derived EVs affected EV-induced ferroptosis in endothelial cells. The mechanism by which GBP2 binds directly to OTUD5 and promotes GPX4 ubiquitination was elucidated using RNA interference, adeno-associated virus transfection, and endothelial-specific Gpx4 knockout mice. A high-throughput screening of small-molecule compounds targeting GBP2 was conducted. Molecular docking, molecular dynamics simulations, and cellular thermal shift assays further confirmed that Plantainoside D (PD) has a potent binding affinity for GBP2. PD treatment inhibited the interaction between GBP2 and OTUD5, leading to a reduction in GPX4 ubiquitination. Further research revealed that PD treatment enhanced the pulmonary protective effects of GBP2 inhibition. In conclusion, this study explored the role of EV-mediated signaling between macrophages and pulmonary vascular endothelial cells in si-ALI, highlighting the GBP2-OTUD5-GPX4 axis as a driver of endothelial ferroptosis and lung injury. Targeting this signaling axis presents a potential therapeutic strategy for si-ALI.

Integrating bioinformatics and machine learning to discover sumoylation associated signatures in sepsis

Small Ubiquitin-like MOdifier-mediated modification (SUMOylation) is associated with sepsis; however, its molecular mechanism remains unclear. Herein, hub genes and regulatory mechanisms in sepsis was investigated. The GSE65682 and GSE95233 datasets were extracted from public databases. Differential analysis and Weighted Gene Co-expression Network Analysis (WGCNA) were conducted in GSE65682 to identify differentially expressed genes (DEGs) and key module genes. Candidate genes were derived by intersecting with SUMOylation-related genes (SUMO-RGs). The Least Absolute Shrinkage and Selection Operator (LASSO) and Support Vector Machine-Recursive Feature Elimination (SVM-RFE) were utilized to identify significant feature genes. The convergence of those genes was utilized for diagnostic assessment and expression validation. Hub genes were defined as those exhibiting an area under the curve (AUC) greater than 0.7, significant gene expression, and a consistent trend. Localization and functional analyses of hub genes were conducted to enhance the understanding of these genes. Immune analysis, regulatory network construction, and drug prediction were performed. Six hub genes were identified: RORA, L3MBTL2, PHC1, RPA1, CHD3, and RANGAP1. These genes possessed considerable diagnostic significance for sepsis and were also markedly downregulated in the condition. Hub genes were predominantly enriched in the ribosome pathway and exhibited a strong correlation with differential immune cells. Activated CD8 + T cells exhibited a positive correlation with RORA. Based on the predicted and established regulatory network, AC004687.1 was observed to modulate PHC1 expression via hsa-miR- 142 - 5p. A total of six hub genes (RORA, L3MBTL2, PHC1, RPA1, CHD3, and RANGAP1) associated with SUMOylation was identified in sepsis in the current study. The findings are likely to aid in the differentiation between control and disease states, offering substantiation for the diagnosis of sepsis.

Study of the relationship between iron metabolism disorders and sepsis-associated liver injury: A prospective observational study

BACKGROUND

Sepsis-associated liver injury (SALI) refers to secondary liver function impairment caused by sepsis, patients with SALI often have worse clinical outcomes. The early identification and assessment of the occurrence and progression of SALI are pressing issues that urgently need to be resolved.

AIM

To investigate the relationship between iron metabolism and SALI.

METHODS

In this prospective study, 139 patients were recruited, with 53 assigned to the SALI group. The relationships between SALI and various iron metabolism-related biomarkers were examined. These biomarkers included serum iron (SI), total iron-binding capacity (TIBC), serum ferritin, transferrin, and transferrin saturation. To identify independent risk factors for SALI, both univariate and multivariate logistic regression analyses were performed. Additionally, receiver operating characteristic curve analysis was utilized to assess the predictive value of these biomarkers for the occurrence of SALI.

RESULTS

There were no statistically significant differences in age, sex, body mass index, Sequential Organ Failure Assessment scores (excluding liver function), or APACHE II scores between the two groups of patients. Compared with the sepsis group, the SALI group presented significantly higher SI (P < 0.001), TIBC (P < 0.001), serum ferritin (P = 0.001), transferrin (P = 0.005), and transferrin saturation levels (P < 0.001). Multivariate logistic regression analysis revealed that SI (odds ratio = 1.24, 95% confidence interval: 1.11-1.40, P < 0.001) and TIBC levels (odds ratio = 1.13, 95% confidence interval: 1.05-1.21, P < 0.001) were independent predictors of SALI. Receiver operating characteristic curve analysis revealed that SI and TIBC had areas under the curve of 0.816 and 0.757, respectively, indicating moderate predictive accuracy for SALI.

CONCLUSION

Iron metabolism disorders are closely associated with the development of SALI, and SI and TIBC may serve as potential predictive biomarkers. The combined use of SI and TIBC has superior diagnostic efficacy for SALI. These findings provide valuable insights for the early identification and management of SALI among patients with sepsis.

Integration of Transcriptomic and Single-Cell Data to Uncover Senescence- and Ferroptosis-Associated Biomarkers in Sepsis

Background: Sepsis is a life-threatening condition characterized by organ dysfunction due to an imbalanced immune response to infection, with high mortality. Ferroptosis, an iron-dependent cell death process, and cellular senescence, which exacerbates inflammation, have recently been implicated in sepsis pathophysiology. Methods: Weighted gene co-expression network analysis (WGCNA) was used to identify ferroptosis- and senescence-related gene modules in sepsis. Differentially expressed genes (DEGs) were analyzed using public datasets (GSE57065, GSE65682, and GSE26378). Receiver operating characteristic (ROC) analysis was performed to evaluate their diagnostic potential, while single-cell RNA sequencing (scRNA-seq) was used to assess their immune-cell-specific expression. Molecular docking was conducted to predict drug interactions with key proteins. Results: Five key genes (CD82, MAPK14, NEDD4, TXN, and WIPI1) were significantly upregulated in sepsis patients and highly correlated with immune cell infiltration. MAPK14 and TXN exhibited strong diagnostic potential (AUC = 0.983, 0.978). Molecular docking suggested potential therapeutic interactions with diclofenac, flurbiprofen, and N-acetyl-L-cysteine. Conclusions: This study highlights ferroptosis and senescence as critical mechanisms in sepsis and identifies promising biomarkers for diagnosis and targeted therapy. Future studies should focus on clinical validation and precision medicine applications.

Ferroptosis-related protein biomarkers for diagnosis, differential diagnosis, and short-term mortality in patients with sepsis in the intensive care unit

Background

Sepsis is a disease with high mortality caused by a dysregulated response to infection. Ferroptosis is a newly discovered type of cell death. Ferroptosis-related genes are involved in the occurrence and development of sepsis. However, research on the diagnostic value of ferroptosis-related protein biomarkers in sepsis serum is limited. This study aims to explore the clinical value of Ferroptosis-related proteins in diagnosing sepsis and predicting mortality risk.

Methods

A single-center, prospective, observational study was conducted from January to December 2023, involving 170 sepsis patients, 49 non-septic ICU patients, and 50 healthy individuals. Upon ICU admission, biochemical parameters, GCS, SOFA, and APACHE II scores were recorded, and surplus serum was stored at -80°C for biomarker analysis via ELISA. Diagnostic efficacy was evaluated using ROC curve analysis.

Results

Baseline serum levels of ACSL4, GPX4, PTGS2, CL-11, IL-6, IL-8, PCT, and hs-CRP significantly differed among sepsis, non-septic, and healthy individuals (all p-value < 0.01). ACSL4, GPX4, PTGS2, IL-6, IL-8, PCT, and hs-CRP demonstrated high diagnostic and differential diagnostic performance (AUC: 0.6688 to 0.9945). IL-10 and TNF-α showed good diagnostic performance (AUC = 0.8955 and 0.7657, respectively). ACSL4 (AUC = 0.7127) was associated with predicting sepsis mortality. Serum levels of ACSL4, CL-11, and IL-6 above the cut-off value were associated with shorter survival times. ACSL4 levels were positively correlated with SOFA (Rho = 0.354, p-value < 0.0001), APACHE II (Rho = 0.317, p-value < 0.0001), and septic shock (Rho = 0.274, p-value = 0.003) scores but negatively correlated with the GCS score (Rho = -0.218, p-value = 0.018). GPX4 levels were positively correlated with SOFA (Rho = 0.204, p-value = 0.027) and APACHE II (Rho = 0.233, p-value = 0.011) scores.

Conclusion

ACSL4 and GPX4 have strong diagnostic and differential diagnostic value in sepsis, including the ability to predict 28-day mortality in sepsis patients, and may become new potential serum markers for the diagnostic and differential diagnostic of sepsis.

Wedelolactone activates the PI3K/AKT/NRF2 and SLC7A11/GPX4 signalling pathways to alleviate oxidative stress and ferroptosis and improve sepsis-induced liver injury

INTRODUCTION

Sepsis-induced liver injury (SILI) is a severe complication of sepsis. Wedelolactone (WEL) can be used to treat liver diseases. However, its therapeutic mechanisms and efficacy in SILI remain unclear. To investigate the therapeutic effects of WEL on SILI and its potential mechanisms of action through in vitro and in vivo experiments.

METHODS

A SILI model based on lipopolysaccharide (LPS), and AML12 cells were treated with different concentrations of WEL, LY294002 and ML385. The SILI model was established by caecal ligation and puncture (CLP). C57BL/6 mice were administered WEL and biphenyl diester for seven consecutive days, and CLP was then performed 1 h later. Blood and liver tissue were collected 24 h later for subsequent analysis. HE staining, liver function index, oxidative stress index, JC-1 staining, transmission electron microscopy, immunofluorescence staining, Western blot, and inflammatory cytokines were used to detect oxidative stress and ferroptosis-related markers.

RESULTS

The in vivo experiments showed that WEL treatment reduced the pathological damage of the liver and decreased ALT and AST, MMP and ROS (the product of iron and lipid peroxidation) and inflammatory factors. WEL also decreased hepatocyte viability in vitro. Inhibition of NRF2 can lead to exacerbation of SILI. The expressions of P-PI3K and P-AKT were up-regulated while HO-1, GPX4, NRF2, and SLC7A11 were down-regulated in vitro and in vivo.

CONCLUSIONS

Ferroptosis and oxidative stress are pivotal in SILI. WEL mitigates SILI by inhibiting ferroptosis and oxidative stress, primarily through the PI3K/AKT/NRF2 and SLC7A11/GPX4 signalling pathways, thus suggesting a promising therapeutic strategy.

Identification and validation of m6A RNA methylation and ferroptosis-related biomarkers in sepsis: transcriptome combined with single-cell RNA sequencing

Background

Sepsis, a systemic inflammatory response syndrome triggered by infection, is associated with high mortality rates and an increasing global incidence. While N 6-methyladenosine (m6A) RNA methylation and ferroptosis are implicated in inflammatory diseases, their specific genes and mechanisms in sepsis remain unclear.

Methods

Transcriptomic datasets of sepsis, along with m6A-related genes (m6A-RGs) and ferroptosis-related genes (FRGs), were sourced from public databases. Differentially expressed genes (DEGs) were identified between the sepsis and control groups, and m6A-RGs were analyzed through weighted gene co-expression network analysis (WGCNA) to uncover m6A module genes. These were then intersected with DEGs and FRGs to identify candidate genes. Biomarkers were identified using two machine learning methods, receiver operating characteristic (ROC) curves, and expression validation, followed by the development of a nomogram. Further in-depth analyses of the biomarkers were performed, including functional enrichment, immune infiltration, drug prediction, and molecular docking. Single-cell analysis was conducted to identify distinct cell clusters and evaluate biomarker expression at the single-cell level. Finally, reverse transcription-quantitative PCR (RT-qPCR) was employed to validate biomarker expression in clinical samples.

Results

DPP4 and TXN were identified as key biomarkers, showing higher expression in control and sepsis samples, respectively. The nomogram incorporating these biomarkers demonstrated strong diagnostic potential. Enrichment analysis highlighted their involvement in spliceosome function and antigen processing and presentation. Differential analysis of immune cell types revealed significant correlations between biomarkers and immune cells, such as macrophages and activated dendritic cells. Drug predictions identified gambogenic acid and valacyclovir as potential treatments, which were successfully docked with the biomarkers. Single-cell analysis revealed that the biomarkers were predominantly expressed in CD4+ memory cells, and CD16+ and CD14+ monocytes. The expression of DPP4 was further validated in clinical samples.

Conclusions

DPP4 and TXN were validated as biomarkers for sepsis, with insights into immune infiltration and therapeutic potential at the single-cell level, offering novel perspectives for sepsis treatment.

Melatonin Exerts Positive Effects on Sepsis Through Various Beneficial Mechanisms

In recent years, our understanding of sepsis has greatly advanced. However, due to the complex pathological and physiological mechanisms of sepsis, the mechanisms of sepsis are currently not fully elucidated, and it is difficult to translate the research results into specific sepsis treatment methods. Melatonin possesses broad anti-inflammatory, antioxidant, and immune-regulatory properties, making it a promising therapeutic agent for sepsis. In recent years, further research has deepened our understanding of the potential mechanisms and application prospects of melatonin in sepsis. The mechanisms underlying the protective effects of melatonin in sepsis are multifaceted. In this review, based on a substantial body of clinical trials and animal research findings, we first highlighted the significance of melatonin as an important biomarker for disease progression and prognosis in sepsis. We also described the extensive regulatory mechanisms of melatonin in sepsis-induced organ damage. In addition to its broad anti-inflammatory, and anti-oxidant effects, melatonin exerts positive effects by regulating metabolic disorders, hemodynamics, cell autophagy, cellular ion channels, endothelial cell permeability, ferroptosis and other complex pathological mechanisms. Furthermore, as a safe exogenous supplement with low toxicity, melatonin demonstrates positive synergistic effects with other anti-sepsis agents. In the face of the urgent medical challenge of transforming the increasing knowledge of sepsis molecular mechanisms into therapeutic interventions to improve patient prognosis, melatonin seems to be a promising option.

Construction of a novel gene signature linked to ferroptosis in pediatric sepsis

Introduction

Pediatric sepsis is a complex and life-threatening condition characterized by organ failure due to an uncontrolled immune response to infection. Recent studies suggest that ferroptosis, a newly identified form of programmed cell death, may play a role in sepsis progression. However, the specific mechanisms of ferroptosis in pediatric sepsis remain unclear.

Methods

In this study, we analyzed microarray datasets from pediatric sepsis and healthy blood samples to identify ferroptosis-associated genes. A protein-protein interaction (PPI) network analysis and histological validation were performed to identify key genes. Additionally, immune infiltration analysis was conducted to explore the correlation between immune cells, immune checkpoint-related genes, and key genes. A competing endogenous RNA (ceRNA) network was constructed to investigate potential regulatory mechanisms involving long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and key ferroptosis-related genes.

Results

We identified 74 genes associated with ferroptosis in pediatric sepsis. Among them, five key genes (MAPK3, MAPK8, PPARG, PTEN, and STAT3) were confirmed through PPI network analysis and histological validation. Immune infiltration analysis revealed significant interactions between immune cells and key genes. The ceRNA network provided insights into the regulatory relationships between lncRNAs, miRNAs, and ferroptosis-related genes.

Discussion

These findings enhance our understanding of the role of ferroptosis in pediatric sepsis and highlight potential therapeutic targets for future research and clinical interventions.

Targeting ferroptosis offers therapy choice in sepsis-associated acute lung injury

Sepsis-associated acute lung injury (SALI) is a common complication of sepsis, consisting of a dysfunctional host response to infection-mediated heterogenous complexes. SALI is reported in up to 50 % of patients with sepsis and causes poor outcomes. Despite high incidence, there is a lack of understanding in its pathogenesis and optimal treatment. A better understanding of the molecular mechanisms underlying SALI may help produce better therapeutics. The effects of altered cell-death mechanisms, such as non-apoptotic regulated cell death (RCD) (i.e., ferroptosis), on the development of SALI are beginning to be discovered, while targeting ferroptosis as a meaningful target in SALI is increasingly being recognized. Here, we outline how a susceptible lung alveoli may develop SALI. Then we discuss the general mechanisms underlying ferroptosis, and how it contributes to SALI. We then outline the chemical structures of the emerging agents or compounds that can protect against SALI by inhibiting ferroptosis, summarizing their potential pharmacological effects. Finally, we highlight key limitations and possible strategies to overcome them. This review suggests that a detailed mechanistic and biological understanding of ferroptosis can foster the development of pharmacological antagonists in the treatment of SALI.

Stigmasterol from Prunella vulgaris L. Alleviates LPS-induced mammary gland injury by inhibiting inflammation and ferroptosis

BACKGROUND

Dairy mastitis, a prevalent condition affecting dairy cattle, represents a significant challenge to both animal welfare and the quality of dairy products. However, current treatment options remain limited. Stigmasterol (ST) is a bioactive component of Prunella vulgaris L. (PV) with various pharmacological functions such as anti-inflammatory and anti-oxidation. At present, the specific effects and underlying mechanisms of PV and ST on dairy mastitis are still not fully understood.

PURPOSE

The aim of this research was to evaluate the pharmacological effects of PV and its active component ST on lipopolysaccharide (LPS) -stimulated bovine mammary epithelial cells (BMECs) and a mouse mastitis model, and to elucidate the possible mechanisms of action.

METHODS

UPLC-Q-TOF-MS/MS was employed to identify the constituents of PV. BMECs and mice were used to establish in vitro and in vivo models of mastitis. Western Blotting, RT-qPCR, immunofluorescence and other techniques were used to explore the effects of PV and ST on inflammatory factors, blood-milk barrier integrity, ferroptosis related indicators and their potential molecular mechanisms.

RESULTS

PV significantly attenuated the production of inflammatory mediators by LPS-stimulated BMECs. Subsequently, ST was found to be a potent anti-inflammatory agent in PV by inhibiting TLR4/NF-κB signaling pathway. This inhibition inhibits the myosin light chain (MLC)/MLC kinase signaling cascade and alleviates blood-milk barrier (BMB) disruption in BMECs. In addition, ferroptosis occurred in BMECs after LPS stimulation, and ST inhibited ferroptosis by stimulating Nrf2/GPX4 signaling pathway. Treatment of BMECs with the Nrf2 inhibitor ML385 significantly attenuated the therapeutic effect of ST. In vivo experiments further confirmed that both PV and ST attenuated LPS-induced breast tissue damage while reducing ferroptosis levels and restoring BMB.

CONCLUSION

ST from PV exhibits substantial anti-inflammatory properties and is a promising candidate for the treatment of dairy mastitis.

ADSCs-derived exosomes suppress macrophage ferroptosis via the SIRT1/NRF2 signaling axis to alleviate acute lung injury in sepsis

Acute lung injury being one of the earliest and most severe complications during sepsis and macrophages play a key role in this process. To investigate the regulatory effects and potential mechanisms of adipose mesenchymal stem cell derived-exosomes (ADSC-exo) on macrophages and septic mice, ADSCs-exo was administrated to both LPS-induced macrophage and cecal ligation and puncture (CLP) induced sepsis mice. ADSCs-exo was confirmed to inhibit M1 polarization of macrophages and to reduce excessive inflammation. The use of ADSCs-exo in CLP mice and in LPS-induced macrophages relieved oxidative stress, cellular damage, and acute lung injury. During this process, ADSCs-exo increased the nuclear translocation of Nrf2, significantly upregulating the activation of the antioxidant pathway Nrf2/HO-1. Concurrently, they enhanced the expression of SIRT1 in macrophages. Further SIRT1 interference experiments demonstrated that ADSCs-exo mitigated macrophage inflammatory responses and LPS-induced ferroptosis by upregulating SIRT1. In the LPS-induced macrophage model, after SIRT1 was interfered with, ADSCs-exo failed to upregulate the Nrf2/HO-1 signaling pathway, leading to enhanced ferroptosis. Finally, in a CLP sepsis mouse model with myeloid-specific SIRT1 knockout, ADSCs-exo was observed to reduce lung tissue injury, oxidative stress damage, and ferroptosis. Still, these beneficial effects were reversed due to the myeloid-specific knockout of SIRT1, while co-administration of a ferroptosis inhibitor rescued this situation, alleviating lung injury and significantly reducing tissue levels of oxidative stress. In conclusion, this study elucidated a novel potential therapeutic mechanism wherein ADSCs-exo upregulates the levels of SIRT1 in macrophages through a non-delivery approach.

Tangeretin alleviates sepsis-induced acute lung injury by inhibiting ferroptosis of macrophage via Nrf2 signaling pathway

BACKGROUND

Sepsis-induced acute lung injury (ALI) is a severe clinical condition accompanied with high mortality. Tangeretin, which is widely found in citrus fruits, has been reported to exert antioxidant and anti-inflammatory properties. However, whether tangeretin protects against sepsis-induced ALI and the potential mechanisms remain unclear.

METHODS

We established an ALI model via intraperitoneally injected with 5 mg/kg lipopolysaccharides (LPS) for 12 h. Tangeretin was applied intraperitoneally 30 min before LPS treatment. Dexamethasone (Dex) was used as a positive control. Hematoxylin and eosin (HE) staining and protein content in bronchoalveolar lavage fluid (BALF) were determined to detect the degree of lung injury. RNA-seq was also applied to explore the effect of tangeretin on ALI. In vitro, RAW264.7 were treated with Nrf2 siRNA, the expression of ferroptosis-associated biomarkers, including glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) were assessed. Glutathione (GSH), malondialdehyde (MDA) levels, reactive oxygen species (ROS) and inflammatory factors were also determined both in vivo and in vitro. Furthermore, mice were treated with an Nrf2 inhibitor (ML385) to verify the mechanism of tangeretin in inhibiting sepsis-induced lung injury and ferroptosis. Data were analyzed using one way analysis of variance or two-tailed unpaired t tests.

RESULTS

Our study demonstrated that tangeretin significantly alleviated lung injury, reversed the LPS-induced reduction in GPX4 and GSH, and mitigates the elevation of PTGS2 and MDA levels. Tangeretin also reduced 4-HNE and iron levels. Besides, the levels of LPS-stimulated inflammatory factors IL-6, IL-1β and TNF-α were also decreased by tangeretin. RNA-seq and bioinformatics analysis demonstrated that tangeretin inhibited inflammatory response. Mechanistically, we identified that tangeretin inhibited the GPX4-dependent lipid peroxidation through activation of Nrf2. The silence of Nrf2 abolished the inhibitory effect of tangeretin on oxidative stress, inflammatory response and ferroptosis in RAW264.7 cells. Additionally, all the protective effects of tangeretin on ALI were abolished in Nrf2 inhibitor-treated mice.

CONCLUSION

We identified that ferroptosis as a critical mechanism contributing to sepsis-induced ALI. Tangeretin, a promising therapeutic candidate, effectively mitigates ALI through inhibiting ferroptosis via upregulating Nrf2 signaling pathway.

Investigation into the influence of mild hypothermia on regulating ferroptosis through the P53-SLC7A11/GPX4 signaling pathway in sepsis-induced acute lung injury

BACKGROUND

Sepsis-induced acute lung injury (S-ALI) significantly contributes to unfavorable clinical outcomes. Emerging evidence suggests a novel role for ferroptosis in the pathophysiology of ALI, though the precise mechanisms remain unclear. Mild hypothermia (32-34 °C) has been shown to inhibit inflammatory responses, reduce oxidative stress, and regulate metabolic processes. P53 has been reported to downregulate the transcriptional activity of solute carrier family 7 member 11 (SLC7A11), thereby limiting cystine uptake. This reduction in cystine availability compromises the activity of Glutathione peroxidase 4 (GPX4), a cystine-dependent enzyme, ultimately increasing cellular susceptibility to ferroptosis. However, it remains unclear whether mild hypothermia exerts protective effects through the P53-SLC7A11/GPX4 signaling pathway. This study investigates the influence of mild hypothermia on ferroptosis mediated by the P53-SLC7A11/GPX4 pathway in S-ALI.

METHODS

This study utilized both in vivo and in vitro models. In the vivo model, 64 Sprague-Dawley rats were employed, with 40 analyzed for survival outcomes. Sepsis was induced using the cecum ligation and puncture (CLP) method, after which rats were subjected to either normothermic (36-38 °C) or mild hypothermic (32-34 °C) conditions for a duration of 10 h. Twelve hours post-surgery, blood samples, bronchoalveolar lavage fluid, and lung tissue samples were harvested for histological analysis, measurement of inflammatory markers, wet/dry ratios, blood gas analysis, assessment of oxidative stress and ferroptosis, Western blotting, and RT-qPCR analysis. In the in vitro model, RLE-6TN cells were exposed to lipopolysaccharide (LPS) for 24 h under normothermic and mild hypothermic conditions. These cells were then evaluated for cell viability, inflammatory markers, oxidative stress levels, ferroptosis markers, as well as Western blot and RT-qPCR analyses.

RESULTS

CLP-induced sepsis led to elevated levels of inflammatory markers, increased lung injury scores, and heightened oxidative stress markers. These detrimental effects were significantly ameliorated by mild hypothermia. Furthermore, mild hypothermia reversed the modified expression of P53, SLC7A11, and GPX4 signaling molecules. Notably, mild hypothermia also improved the 5-day survival rate of CLP rats.

CONCLUSION

Mild hypothermia attenuates S-ALI and modulates ferroptosis through the P53-SLC7A11/GPX4 signaling pathway.

Mitochondrial dysfunction is a major cause of thromboinflammation and inflammatory cell death in critical illnesses

BACKGROUND

Mitochondria generate the adenosine triphosphate (ATP) necessary for eukaryotic cells, serving as their primary energy suppliers, and contribute to host defense by producing reactive oxygen species. In many critical illnesses, including sepsis, major trauma, and heatstroke, the vicious cycle between activated coagulation and inflammation results in tissue hypoxia-induced mitochondrial dysfunction, and impaired mitochondrial function contributes to thromboinflammation and cell death.

METHODS

A computer-based online search was performed using the PubMed and Web of Science databases for published articles concerning sepsis, trauma, critical illnesses, cell death, mitochondria, inflammation, coagulopathy, and organ dysfunction.

RESULTS

Mitochondrial outer membrane permeabilization triggers apoptosis by releasing cytochrome c and activating caspases. Apoptosis is a non-inflammatory programmed cell death but requires sufficient ATP supply. Therefore, conversion to inflammatory necrosis may occur due to a lack of ATP in critical illness. Severely damaged mitochondria release excess reactive oxygen species and injurious mitochondrial DNA, inducing cell death. Besides non-programmed necrosis, mitochondrial damage can trigger programmed inflammatory cell death, including necroptosis, pyroptosis, and ferroptosis. Additionally, a unique form of DNA-ejecting cell death, known as etosis, occurs in monocytes and granulocytes following external stimuli and mitochondrial damage. The type of cell death chosen remains uncertain but is known to depend on the cell type, the nature of the injury, and the degree of damage.

CONCLUSIONS

Mitochondria damage is the major contributor to the cell death mechanism that leads to organ damage in critical illnesses. Regulating and restoring mitochondrial function holds promise for developing new therapeutic approaches for mitigating critical diseases.

What do we know about micronutrients in critically ill patients? A narrative review

Micronutrient (MN) status alterations (both depletion and deficiency) are associated with several complications and worse outcomes in critically ill patients. On the other side of the spectrum, improving MN status has been shown to be a potential co-adjuvant therapy. This review aims to collect existing data to better guide research in the critical care setting. This narrative review was conducted by the European Society of Intensive Care Medicine Feeding, Rehabilitation, Endocrinology, and Metabolism MN group. The primary objective was to identify studies focusing on individual MNs in critically ill patients, selecting the MNs that appear to be most relevant and most frequently investigated in the last decade: A, B1, B2, B3, B6, folate, C, D, E, copper, iron, selenium, zinc, and carnitine. Given the limited number of interventional studies for most MNs, observational studies were included. For each selected MN, the review summarizes the main form and functions, special needs and risk factors, optimal treatment strategies, pharmacological dosing, and clinical implications all specific to critically ill patients. A rigorous rebalancing of research strategies and priorities is needed to improve clinical practice. An important finding is that high-dose monotherapy of MNs is not recommended. Basal daily needs must be provided, with higher doses in diseases with known higher needs, and identified deficiencies treated. Finally, the review provides a list of ongoing trials on MNs in critically ill patients and identifies a priority list of future research topics.

IDENTIFYING POTENTIAL KEY FERROPTOSIS-RELATED GENES AND THERAPEUTIC DRUGS IN SEPSIS-INDUCED ARDS BY BIOINFORMATICS AND EXPERIMENTAL VERIFICATION

ABSTRACT

Background: Acute respiratory distress syndrome (ARDS) is a serious pathological process with high mortality. Ferroptosis is pivotal in sepsis, whose regulatory mechanisms in sepsis-induced ARDS remains unknown. We aimed to determine key ferroptosis-related genes in septic ARDS and investigate therapeutic traditional Chinese medicine. Method: Sepsis-induced ARDS dataset obtained from Gene Expression Omnibus was analyzed to identify ferroptosis-related differentially expressed genes. Enrichment analysis and protein-protein interaction network construction were performed to identify hub genes. Immune cells infiltration was analyzed and competitive endogenous RNA network was constructed. The diagnostic value of hub genes in septic ARDS was analyzed and the occurrence of ferroptosis and the expression of hub genes were detected. Traditional Chinese medicine targeting hub genes was predicted via SymMap database and was verified. Results: Sixteen ferroptosis-related differentially expressed genes were obtained, among which the top four genes ( IL1B , TXN , MAPK3 , HSPB1 ) were selected as hub genes, which may be potential diagnostic markers of septic ARDS. Immunoassay showed that sepsis-induced ARDS and hub genes were closely related to immune cells. The competitive endogenous RNA network showed 26 microRNAs and 38 long noncoding RNA. Ferroptosis occurred and the expressions of IL1B , MAPK3 , and TXN were increased in septic ARDS mice and LPS-challenged human pulmonary alveolar epithelial cells. Sea buckthorn alleviated septic lung injury and affected hub genes expression. Conclusions: Ferroptosis-related genes of IL1B , MAPK 3, and TXN serve as potential diagnostic genes for sepsis-induced ARDS. Sea buckthorn may be therapeutic medication for ARDS. This study provides a new direction for septic ARDS treatment.

Identification of STAT3 and MYC as critical ferroptosis-related biomarkers in septic cardiomyopathy: a bioinformatics and experimental study

Ferroptosis is the well-known mechanism of septic cardiomyopathy (SCM). Bioinformatics analysis was employed to identify ferroptosis-related SCM differentially expressed genes (DEG). DEGs' functional enrichment was explored. Weighted gene co-expression network analysis (WGCNA) was employed to form gene clusters. The identified hub genes, signal transducer and activator of transcription 3 (STAT3) and myelocytomatosis (MYC) were further evaluated by generating receiver operator characteristic (ROC) curves and a nomogram prediction model. Additionally, survival rate, cardiac damage markers, and cardiac function and ferroptosis markers were evaluated in septic mouse model. STAT3 and MYC levels were measured in SCM heart tissue via immunohistochemical (IHC) staining, real-time polymerase chain reaction (qPCR) and western blot analysis. Analysis identified 225 DEGs and revealed 22 intersected genes. Of the 7 hub genes, STAT3 and MYC showed enrichment in septic heart tissue and a strong predicative ability based on AUC values. Cardiac damage, iron metabolism, and lipid peroxidation occurred in the SCM model. By experiments, STAT3 and MYC expression was increased in the SCM model. Impairment was reversed with a ferroptosis inhibitor, Fer-1. As conclusion, STAT3 and MYC are related with ferroptosis and may serve as potential SCM predictor indicators. KEY MESSAGES: Septic cardiomyopathy (SCM) often leads to high mortality in septic patients, and the diagnostic criteria still remains unclear. Ferroptosis as the pathogenic mechanism of SCM could help predict its progression and clinical outcomes. STAT3 and MYC are related with ferroptosis and may serve as potential SCM predictor biomarkers.

Shielding the Gut: Ghrelin and Ferrostatin-1's Protective Role Against Sepsis-Induced Intestinal Ferroptosis

Objective: This study investigates the therapeutic efficacy of ghrelin in alleviating sepsis-induced intestinal damage, focusing on its potential to inhibit ferroptosis and protect intestinal barrier integrity. Methods: This study evaluates the therapeutic efficacy of intraperitoneal ghrelin (80 μg/kg) and Ferrostatin-1 (5 mg/kg) using a cecal ligation and puncture (CLP) model in C57BL/6 mice to determine their potential in alleviating sepsis-induced intestinal damage. The investigation focuses on the impacts of ghrelin and Ferrostatin-1 on bacterial load, intestinal morphology, systemic inflammation, oxidative stress, and ferroptosis markers. Our comprehensive methodology encompasses histopathological evaluations, cytokine profiling, oxidative stress assays, and detailed analyses of ferroptosis indicators to thoroughly assess the interventions' efficacy. Results: Treatment with ghrelin significantly reduced bacterial proliferation, mitigated intestinal damage, and decreased systemic inflammation. Comparable outcomes were observed with Fer-1 treatment. Both interventions restored intestinal barrier functions, modulated inflammatory responses, and attenuated oxidative stress, indicating a suppression of the ferroptosis pathway. Conclusion: Ghrelin exhibits a protective role in sepsis-induced intestinal injury, likely through the inhibition of ferroptosis. This mechanism underscores ghrelin's therapeutic potential in sepsis management, suggesting avenues for further clinical exploration.

The VDR/FFAR2 axis mitigates sepsis-induced lung injury by suppressing macrophage lipid peroxidation

Sepsis-induced lung injury is a common critical condition in clinical practice, characterized by the accumulation of peroxides and inflammatory damage caused by excessive macrophage activation. Currently, effective treatments for sepsis-induced lung injury are lacking. Short-chain fatty acid receptor FFAR2 serves as an anti-inflammatory biomarker, but its role and mechanism in sepsis-induced lung injury remain unclear. To elucidate the influence and mechanism of FFAR2 on macrophage lipid peroxidation levels in sepsis-induced lung injury, this study conducted bioinformatics analysis and cellular experiments using the THP-1 macrophage cell line. By dual luciferase reporter and chromatin immunoprecipitation-quantitative PCR assays, it is confirmed that the transcription factor VDR upregulates FFAR2 expression in macrophages by binding to the promoter region -1695 ∼ 1525, thereby increasing the expression of iron death negative regulatory molecules and lowering macrophage lipid peroxidation levels. Moreover, both in vitro using THP-1 cells and bone marrow-derived macrophages (BMDMs) and in vivo using an LPS-induced septic mice model experiments revealed that activating the VDR/FFAR2 axis could reduce inflammation-induced macrophage lipid peroxide accumulation and alleviate lung injury in septic mice. This finding highlights the potential of FFAR2 as an immunotherapeutic target for mitigating sepsis-related lung injury.

Ferroptosisand Its Role in the Treatment of Sepsis-Related Organ Injury: Mechanisms and Potential Therapeutic Approaches

Sepsis is a complicated clinical disease caused by a defective host response to infection, leading to elevated morbidity and fatality globally. Sepsis patients have a significant risk of life-threatening organ damage, including hearts, brains, lungs, kidneys, and livers. Nevertheless, the molecular pathways driving organ injury in sepsis are not well known. Ferroptosis, a non-apoptotic cell death, occurs due to iron metabolism disturbance and lipid peroxide buildup. Multiple studies indicate that ferroptosis has a significant role in decreasing inflammation and lipid peroxidation during sepsis. Ferroptosis inhibitors and medications, aimed at the most studied ferroptosis process, including Xc-system, Nrf2/GPX4 axis, and NCOA4-FTH1-mediated ferritinophagy, alleviating sepsis effectively. However, few clinical trials demonstrated ferroptosis-targeted drugs's effectiveness in sepsis. Our study examines ferroptosis-targeted medicinal agents and their potential benefits for treating sepsis-associated organ impairment. This review indicates that ferroptosis suppression by pharmaceutical means may be a useful therapy for sepsis-associated organ injury.

The role of cGAS-STING signaling pathway in ferroptosis

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway has been identified as a crucial mechanism in antiviral defense and innate immunity pathway. Ferroptosis, characterized by iron dependence and lipid peroxidation, represents a specialized form of cell death. A burgeoning collection of studies has demonstrated that the cGAS-STING signaling pathway participates in the homeostatic regulation of the organism by modulating ferroptosis-associated enzyme activity or gene expression. Consequently, elucidating the specific roles of the STING signaling pathway and ferroptosis in vivo is vital for targeted disease intervention. This review systematically examines the interactions between the cGAS-STING signaling pathway and ferroptosis, highlighting their influence on disease progression in the contexts of inflammation, injury, and cancerous cell dynamics. Understanding these interactions may provide novel therapeutic strategies. The STING pathway has been implicated in the regulation of various cell death mechanisms, including apoptosis, pyroptosis, necroptosis, autophagy, and ferroptosis. Our focus primarily addresses the role and mechanism of the cGAS-STING signaling pathway and ferroptosis in diseases, limiting discussion of other cell death modalities and precluding a comprehensive overview of the pathway's additional functions.

Maresin1 Inhibits Ferroptosis via the Nrf2/SLC7A11/GPX4 Pathway to Protect Against Sepsis-Induced Acute Liver Injury

Purpose

Maresin 1 (MaR1) is a specialized pro-resolving mediator with anti-inflammatory properties that promotes tissue repair. This study aims to investigate the molecular involvement of MaR1 in protecting against sepsis-induced acute liver injury (SI-ALI).

Methods

In vivo, a murine SI-ALI model was established using the cecal ligation and puncture (CLP) paradigm, providing a system in which the mechanistic functions of MaR1 could be tested. These analyses were supplemented through in vitro assays in which Alpha mouse liver 12 (AML12) hepatocytes and RAW264.7 macrophages were co-cultured in a Transwell system, with lipopolysaccharide (LPS) stimulation being used to establish a sepsis model. These cells were treated with MaR1 and/or nuclear factor erythroid 2-related factor 2 (Nrf2)inhibitor, while lentiviral transduction was used to knock down Nrf2 within AML12 cells. Hepatic pathological damage was assessed through hematoxylin and eosin staining. Lipid peroxidation-related analyses were conducted through the use of thiobarbituric acid, ferrous ions, glutathione, and appropriate fluorescent probes for reactive oxygen species detection. Liver enzymes and inflammatory mediators were quantified using appropriate Enzyme-Linked Immunosorbent Assays (ELISAs). Protein concentrations were evaluated via Western blot analysis.

Results

The presence of ferroptosis in SI-ALI. MaR1 was found to proficiently suppress ferroptosis in SI-ALI. Mechanistically, MaR1 enhanced Nrf2 expression in AML12 hepatocytes, while the Nrf2 inhibitor ML-385 or Nrf2 siRNA mitigated MaR1's regulatory influence on ferroptosis. Meanwhile, the expressions of the downstream genes solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) diminished, suggesting that MaR1 has a protective function via activating the Nrf2/SLC7A11/GPX4 pathway to mitigate ferroptosis in septic liver injury.

Conclusion

The results indicate that MaR1 mitigates SI-ALI via stimulating the Nrf2/SLC7A11/GPX4 pathway to suppress ferroptosis. Moreover, it offers significant potential as a new agent for the prevention of SI-ALI.

Pentraxin-3 modulates hepatocyte ferroptosis and the innate immune response in LPS-induced liver injury

The liver plays a crucial role in the immune response during endotoxemia and is one of the critical targets for sepsis-related injuries. As a secretory factor involved in inflammation, pentraxin-3 (PTX3) has been demonstrated to regulate hepatic homeostasis; however, the relationship between PTX3 and cell crosstalk between immune cells and hepatocytes in the liver remains incompletely understood. In this study, we revealed that, compared with WT mice, Ptx3-/- mice with lipopolysaccharide (LPS)-induced endotoxemia exhibited alleviated liver damage, with reduced serum alanine transaminase and aspartate transaminase levels and an improved survival rate. Mechanistically, RNA-Seq and western blot results revealed that Ptx3 knockdown in hepatocytes increased the expression of Tfrc and Ccl20; consequently, Ptx3 deficiency regulated LPS-induced hepatocyte ferroptosis via increased mitochondrial reactive oxygen species and Fe2+ and recruited more macrophages by CCL20/CCR6 axis to be involved in inflammation and the clearance of harmful substances. Moreover, western blot and immunofluorescence staining confirmed that the NF-κB signaling pathway was upregulated upon LPS treatment in Ptx3-knockdown macrophages, promoting phagocytosis and polarization toward M1 macrophages. Collectively, our findings show that the absence of Ptx3 can ameliorate sepsis-induced liver injury by regulating hepatocyte ferroptosis and promote the recruitment and polarization of M1 macrophages. These findings offer a key basis for the development of effective treatments for acute infections.

Immunoadjuvant therapy in the regulation of cell death in sepsis: recent advances and future directions

Sepsis is characterized by a concomitant early pro-inflammatory response by immune cells to an infection, and an opposing anti-inflammatory response that results in protracted immunosuppression. The primary pathological event in sepsis is widespread programmed cell death, or cellular self-sacrifice, of innate and adaptive immune cells, leading to profound immunological suppression. This severe immune dysfunction hampers effective primary pathogen clearance, thereby increasing the risk of secondary opportunistic infections, latent viral reactivation, multiple organ dysfunction, and elevated mortality. The types of cell death include apoptosis (type I programmed cell death), autophagy (type II programmed cell death), NETosis (a program for formation of neutrophil extracellular traps (NETs)) and other programmed cell deaths like pyroptosis, ferroptosis, necroptosis, each contributing to immunosuppression in distinct ways during the later phases of sepsis. Extensive apoptosis of lymphocytes, such as CD4+, CD8+ T cells, and B cells, is strongly associated with immunosuppression. Apoptosis of dendritic cells further compromises T and B cell survival and can induce T cell anergy or promote regulatory Treg cell proliferation. Moreover, delayed apoptosis and impaired neutrophil function contribute to nosocomial infections and immune dysfunction in sepsis. Interestingly, aberrant NETosis and the subsequent depletion of mature neutrophils also trigger immunosuppression, and neutrophil pyroptosis can positively regulate NETosis. The interaction between programmed cell death 1 (PD-1) or programmed cell death 1 ligand (PD-L1) plays a key role in T cell modulation and neutrophil apoptosis in sepsis. The dendritic cell growth factor, Fms-like tyrosine kinase (FLTEL), increases DC numbers, enhances CD 28 expression, attenuates PD-L1, and improves survival in sepsis. Recently, immunoadjuvant therapies have attracted attention for their potential to restore host physiological immunity and homeostasis in patients with sepsis. This review focuses on several potential immunotherapeutic agents designed to bolster suppressed innate and adaptive immune responses in the management of sepsis.

Ferroptosis in Cardiovascular Diseases and Ferroptosis-Related Intervention Approaches

OBJECTIVE

Cardiovascular diseases (CVDs) are major public health problems that threaten the lives and health of individuals. The article has reviewed recent progresses about ferroptosis and ferroptosis-related intervention approaches for the treatment of CVDs and provided more references and strategies for targeting ferroptosis to prevent and treat CVDs.

METHODS

A comprehensive review was conducted using the literature researches.

RESULTS AND DISCUSSION

Many ferroptosis-targeted compounds and ferroptosis-related genes may be prospective targets for treating CVDs and our review provides a solid foundation for further studies about the detailed pathological mechanisms of CVDs.

CONCLUSION

There are challenges and limitations about the translation of ferroptosis-targeted potential therapies from experimental research to clinical practice. It warrants further exploration to pursure safer and more effective ferroptosis-targeted thereapeutic approaches for CVDs.

Role of Hippo/ACSL4 axis in ferroptosis-induced pericyte loss and vascular dysfunction in sepsis

Sepsis is a critical condition characterized by a systemic inflammatory response to infection, often leading to severe vascular dysfunction and high mortality. One of the hallmarks of vascular dysfunction in sepsis is increased vascular permeability and the loss of pericytes, which are essential for maintaining vascular integrity. Despite the significance of pericyte loss in sepsis, the primary type of cell death responsible and the underlying molecular mechanisms remain incompletely understood. This study aims to elucidate these mechanisms by focusing on ferroptosis, a form of programmed cell death, and its regulation through the Hippo/ACSL4 axis. Our research confirmed significant pericyte loss in patients with sepsis. Through advanced single-cell analysis and proteomics, ferroptosis was identified as a key differentiating cell death type between sepsis and sham samples. Further metabolomics analysis revealed that Acyl-CoA Synthetase Long-Chain Family Member 4 (ACSL4) plays a pivotal role in the ferroptosis of pericytes during sepsis. In vitro experiments demonstrated that downregulation of ACSL4 effectively reduced lipopolysaccharide (LPS)-induced lipid peroxidation, restored pericyte viability, and improved endothelial permeability. In vivo studies with pericyte-specific ACSL4 knockout mice showed a marked decrease in pericyte loss and enhanced vascular barrier function following sepsis induction. To translate these findings into potential therapeutic strategies, we developed pericyte-targeting liposomes encapsulating ACSL4 shRNA adenovirus. These liposomes successfully restored pulmonary vascular barrier function and significantly reduced pericyte loss in septic conditions. The results of this study underscore the crucial role of ACSL4 in mediating ferroptosis in pericytes and highlight the therapeutic potential of targeting ACSL4 to mitigate vascular dysfunction in sepsis.

Oxidative/Nitrosative Stress and Brain Involvement in Sepsis: A Relationship Supported by Immunohistochemistry

Background and Objectives: A large amount of recent evidence suggests that cellular inability to consume oxygen could play a notable part in promoting sepsis as a consequence of mitochondrial dysfunction and oxidative stress. The latter could, in fact, represent a fundamental stage in the evolution of the "natural history" of sepsis. Following a study previously conducted by the same working group on heart samples, the present research project aims to evaluate, through an immunohistochemical study, the existence and/or extent of oxidative stress in the brains of subjects who died due to sepsis and define, after reviewing the literature, its contribution to the septic process to support the use of medications aimed at correcting redox anomalies in the management of septic patients. Materials and Methods: 10 cases of subjects who died in healthcare facilities with ante-mortem clinical-laboratory signs that allowed the diagnosis of septic shock were selected as case studies, and 1 case of a subject who died immediately following a road traffic accident was used as a negative control. Samples of the cerebral cortex were then taken, fixed in formalin, and subjected to sections on which an immunohistochemical study was performed using anti-NOX-2, NT, iNOS, and 8-OHdG antibodies. Results: The results emerging from the present study demonstrate that despite a variable expressivity for the NT, iNOS, and NOX2 markers, the brain samples demonstrated univocal and high positivity for the 8-OHdG marker. Conclusions: This would allow us to hypothesize how, regardless of the mechanism of production of ROS and NOS (iNOS or NOX2 mediated) and the pathophysiological mechanisms that are triggered during sepsis, oxidative damage to DNA represents the event to which this whole process leads and, in fact, in the literature, is directly correlated to sepsis-dependent mortality. Neurons, conversely, appear to be more sensitive to oxidative stress because of a low number of protective or scavenger molecules (catalase, glutathione peroxidase, GSH, or vitamin E). Therefore, despite reduced production, the manifestation of the damage remains high. This evidence, together with that of the previous study, can only support the introduction of substances with an antioxidant function in the guidelines for the treatment of sepsis.

Epigenetic mechanism of EZH2-mediated histone methylation modification in regulating ferroptosis of alveolar epithelial cells in sepsis-induced acute lung injury

Sepsis-induced acute lung injury (SI-ALI) leads to significant deaths in critically ill patients worldwide. This study explores the mechanism of EZH2 regulating ferroptosis of alveolar epithelial cells (AECs) in SI-ALI. In vitro cell model and in vivo mouse lung injury model of sepsis were established. EZH2 expression in lung tissues was intervened by sh-EZH2, followed by H&E staining observation of lung tissue pathological changes. EZH2, H3K27me3, USP10, GPX4, and ACSL4 expressions were determined by qRT-PCR or Western blot. ROS, GSH, and iron ion levels were detected using fluorescent labeling and reagent kits, respectively. ChIP analyzed the enrichment of EZH2 and H3K27me3 on USP10 promoter. The binding between USP10 and GPX4, and the ubiquitination level of GPX4 were detected using Co-IP. EZH2 was highly expressed in lung tissues of SI-ALI mice. EZH2 silencing alleviated ALI and ferroptosis of AECs; EZH2 increased the H3K27me3 level on USP10 promoter through histone methylation. USP10 stabilized GPX4 protein expression through ubiquitination; inhibition of USP10 partially reversed the inhibitory effect of EZH2 silencing on ferroptosis of AECs. In conclusion, EZH2 depresses USP10 expression by promoting histone H3K27me3 modification on USP10 promoter, thereby enhancing ubiquitination degradation of GPX4 and ultimately facilitating ferroptosis of AECs in sepsis.

The role of inflammatory response and metabolic reprogramming in sepsis-associated acute kidney injury: mechanistic insights and therapeutic potential

Sepsis represents a severe condition characterized by organ dysfunction resulting from a dysregulated host response to infection. Among the organs affected, the kidneys are particularly vulnerable, with significant functional impairment that markedly elevates mortality rates. Previous researches have highlighted that both inflammatory response dysregulation and metabolic reprogramming are crucial in the onset and progression of sepsis associated acute kidney injury (SA-AKI), making these processes potential targets for innovative therapies. This study aims to elucidate the pathophysiological mechanisms of renal injury in sepsis by perspective of inflammatory response dysregulation, with particular emphasis on pyroptosis, necroptosis, autophagy, and ferroptosis. Furthermore, it will incorporate insights into metabolic reprogramming to provide a detailed analysis of the mechanisms driving SA-AKI and explore potential targeted therapeutic strategies, providing solid theoretical framework for the development of targeted therapies for SA-AKI.

Aspirin use is associated with the reduced mortality risk in chronic obstructive pulmonary disease with sepsis: a retrospective study using the MIMIC-IV database

Background

Sepsis has the characteristics of high morbidity and high mortality in intensive care unit (ICU) patients. Chronic obstructive pulmonary disease (COPD) is an important cause of death. Studies have shown the value of aspirin on COPD and sepsis, separately, but its role in the combined COPD and sepsis patients is unclear. This study aimed to analyze the association of aspirin use after ICU admission with the mortality risk in COPD patients with sepsis.

Methods

We conducted a retrospective study using the Medical Information Mart for Intensive Care (MIMIC)-IV database, enrolling 2,964 COPD patients with sepsis admitted to ICU. They were divided into aspirin users (n=1,642) and non-users (n=1,322). We evaluated the association of aspirin use with in-hospital and 28-day mortality using logistic regression, Kaplan-Meier survival analysis, and Cox proportional-hazards models. The role of aspirin dose and the association of aspirin use with 90-day and 1-year mortality were also assessed.

Results

Aspirin use was associated with lower in-hospital death (13.642% vs. 23.676%) and 28-day mortality (17.296% vs. 30.257%) (P<0.001). Adjusted models confirmed reduced mortality odds ratio (OR) with aspirin use: OR for in-hospital mortality was 0.574 [95% confidence interval (CI): 0.456, 0.721] and 28-day mortality was 0.539 (95% CI: 0.437, 0.665) in model 3. Survival analyses showed higher survival probabilities for aspirin users. Subgroup analyses supported consistent aspirin benefits across various clinical parameters. Additionally, aspirin users had lower 90-day (21.498% vs. 34.191%) and 1-year mortality (27.649% vs. 41.982%) (P<0.001).

Conclusions

Aspirin use is significantly related to in-hospital and 28-day mortality risk in COPD patients with sepsis. This highlighted the clinical relevance of aspirin in COPD patients with sepsis.

Enhancing insight into ferroptosis mechanisms in sepsis: A genomic and pharmacological approach integrating single-cell sequencing and Mendelian randomization

This research investigated the intricate relationship between ferroptosis and sepsis by utilizing advanced genomic and pharmacological methodologies. Specifically, we obtained expression quantitative trait loci (eQTLs) for 435 genes associated with ferroptosis from the eQTLGen Consortium and detected notable cis-eQTLs for 281 of these genes. Next, we conducted a detailed analysis to assess the impact of these eQTLs on susceptibility to sepsis using Mendelian randomization (MR) with data from a cohort of 10,154 sepsis patients and 452,764 controls sourced from the UK Biobank. MR analysis revealed 16 ferroptosis-related genes that exhibited significant associations with sepsis outcomes. To bolster the robustness of these findings, sensitivity analyses were performed to assess pleiotropy and heterogeneity, thus confirming the reliability of the causal inferences. Furthermore, single-cell RNA sequencing data from sepsis patients offered a detailed examination of gene expression profiles, demonstrating varying levels of ferroptosis marker expression across different cell types. Pathway enrichment analysis utilizing gene set enrichment analysis (GSEA) further revealed the key biological pathways involved in the progression of sepsis. Additionally, the use of computational molecular docking facilitated the prediction of interactions between identified genes and potential therapeutic compounds, highlighting novel drug targets. In conclusion, our integrated approach combining genomics and pharmacology offers valuable insights into the involvement of ferroptosis in sepsis, laying the groundwork for potential therapeutic strategies targeting this cell death pathway to enhance sepsis management.

Low miR-936-mediated upregulation of Pim-3 drives sorafenib resistance in liver cancer through ferroptosis inhibition by activating the ANKRD18A/Src/NRF2 pathway

Objective

Sorafenib, a multikinase inhibitor, is currently the standard treatment for advanced liver cancer. However, its application has become limited by the development of drug resistance. We intended to explore the mechanisms underlying the development of sorafenib resistance, therefore identifying an effective strategy to overcome sorafenib resistance remain challenges.

Methods

Here, the follow-up of liver cancer patients undergoing sorafenib therapy, as well as animal tumor challenge and treatment were performed. The sorafenib-resistant liver cancer cell lines Huh7/SOR and HepG2/SOR were also established. miRNA and mRNA microarray analyses, TargetScan prediction, dual luciferase reporter assay, RNA pull-down assay, co-mmunoprecipitation (Co-IP) and pull-down assays, a transcription factor-specific NRF2 assay, an iron detection assay, a lipid peroxidation quantification assay, a ROS measurement assay, and GSH/GSSG and GSH-px standard quantitative assays were used.

Results

We showed that upregulation of the provirus-integrating site for Moloney murine leukemia virus 3 (Pim-3) predicted poor response and unsatisfactory prognosis in sorafenib-treated liver cancer patients. Similarly, Pim-3 expression was positively associated with sorafenib resistance in liver cancer cells. Furthermore, microRNA-936 (miR-936) targeted the 3'-noncoding region (3'-UTR) of Pim-3 but exhibited lower expression in sorafenib-resistant liver cancer cells than in their parental cells. The high expression of Pim-3 mediated by miR-936 insufficiency activated the ANKRD18A/Src/NRF2 pathway which rearranged the expression of the indicated markers involved in iron distribution and lipid peroxidation homeostasis. MiR-936 overexpression and GV102-Pim-3-shRNA significantly attenuated the activity of the ANKRD18A/Src/NRF2 pathway to decrease the expression of Ankyrin repeat domain-containing protein 18A (ANKRD18A), Src, and Nuclear factor (erythroid-derived 2)-like 2 (NRF2), especially decreasing NRF2 nuclear retention and transcriptional activity. The transcriptional activity of NRF2 prompted cell ferroptosis because the transfection of miR-936 mimics, GV102-Pim-3-shRNA and GV102-NRF2-shRNA plasmid increased the expression of transferrin receptor 1 (TFR1) and divalent metal transporter 1 (DMT1) but decreased the expression of solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1), thus facilitating the accumulation of intracellular Fe2+, lipid peroxides, and reactive oxygen species (ROS) but reducing the glutathione (GSH) level. Moreover, the elevated expression of Pim-3, resulting from the absence of miR-936 enhances sorafenib resistance in liver cancer by inhibiting cell ferroptosis.

Conclusion

Pim-3 can be regarded as a target in the treatment of sorafenib-resistant liver cancer.

Natural hydrogen gas and engineered microalgae prevent acute lung injury in sepsis

Background

Hydrogen gas and microalgae both exist in the natural environment. We aimed to integrate hydrogen gas and biology nano microalgae together to expand the treatment options in sepsis.

Methods

Phosphoproteomics, metabolomics and proteomics data were obtained from mice undergoing cecum ligation and puncture (CLP) and inhalation of hydrogen gas. All omics analysis procedure were accordance with standards. Multi R packages were used in single cell and spatial transcriptomics analysis to identify primary cells expressing targeted genes, and the genes' co-expression relationships in sepsis related lung landscape. Then, network pharmacology method was used to identify candidate drugs. We used hydrophobic-force-driving self-assembly method to construct dihydroquercetin (DQ) nanoparticle. To cooperate with molecular hydrogen, ammonia borane (B) was added to DQ surface. Then, Chlorella vulgaris (C) was used as biological carrier to improve self-assembly nanoparticle. Vivo and vitro experiments were both conducted to evaluate anti-inflammation, anti-ferroptosis, anti-infection and organ protection capability.

Results

As a result, we identified Esam and Zo-1 were target phosphorylation proteins for molecular hydrogen treatment in lung. Ferroptosis and glutathione metabolism were two target pathways. Chlorella vulgaris improved the dispersion of DQB and reconstructed morphological features of DQB, formed DQB@C nano-system (size = 307.3 nm, zeta potential = -22mv), with well infection-responsive hydrogen release capability and biosafety. In addition, DQB@C was able to decrease oxidative stress and inflammation factors accumulation in lung cells. Through increasing expression level of Slc7a11/xCT and decreasing Cox2 level to participate with the regulation of ferroptosis. Also, DQB@C played lung and multi organ protection and anti-inflammation roles on CLP mice.

Conclusion

Our research proposed DQB@C as a novel biology nano-system with enormous potential on treatment for sepsis related acute lung injury to solve the limitation of hydrogen gas utilization in clinics.

Focus on the role of calcium signaling in ferroptosis: a potential therapeutic strategy for sepsis-induced acute lung injury

By engaging in redox processes, ferroptosis plays a crucial role in sepsis-induced acute lung injury (ALI). Although iron stimulates calcium signaling through the stimulation of redox-sensitive calcium pathways, the function of calcium signals in the physiological process of ferroptosis in septic ALI remains unidentified. Iron homeostasis disequilibrium in ferroptosis is frequently accompanied by aberrant calcium signaling. Intracellular calcium overflow can be a symptom of dysregulation of the cellular redox state, which is characterized by iron overload during the early phase of ferroptosis. This can lead to disruptions in calcium homeostasis and calcium signaling. The mechanisms controlling iron homeostasis and ferroptosis are reviewed here, along with their significance in sepsis-induced acute lung injury, and the potential role of calcium signaling in these processes is clarified. We propose that the development of septic acute lung injury is a combined process involving the bidirectional interaction between iron homeostasis and calcium signaling. Our goal is to raise awareness about the pathophysiology of sepsis-induced acute lung injury and investigate the relationship between these mechanisms and ferroptosis. We also aimed to develop calcium-antagonistic therapies that target ferroptosis in septic ALI and improve the quality of survival for patients suffering from acute lung injury.

Time of day-dependent alterations of ferroptosis in LPS-induced myocardial injury via Bmal-1/AKT/ Nrf2 in rat and H9c2 cell

Background

One of the most prevalent causes of death in sepsis is sepsis-induced cardiomyopathy (SICM). Circadian disruption is involved in the progress of sepsis. However, the molecular mechanism remains unclear.

Methods

Here, we built LPS-induced SICM in-vivo and in-vitro models. LPS was administrated at the particular Zeitgeber times (ZT), ZT4-ZT10-ZT16-ZT22 and ZT10-ZT22 in vivo and vitro experiments, respectively.

Results

In vivo experiment, injection of LPS at ZT10 induced higher infiltration of inflammatory cells and content of intracellular Fe2+, and lower level of Glutathione peroxidase 4 (GPX4) and cardiac function than other ZTs (P < 0.05), which indicated that myocardial ferroptosis in septic rat presented a time of day-dependent manner. Bmal-1 protein and mRNA levels of injection of LPS at ZT10 were lower than those at other three ZTs (P < 0.05). The ratios of pAKT/AKT at ZT4 and ZT10 LPS injection were lower than those at ZT16 and ZT22 (P < 0.05). Nrf2 protein levels at ZT10 LPS injection were lower than those at other three ZTs (P < 0.05). These results indicated that the circadian of Bmal-1 and its downstream AKT/Nrf2 pathway in rat heart were inhibited under SICM condition. Consistent with in-vivo experiment, we found LPS could significantly reduce the expressions of Bmal-1 protein and mRNA in H9c2 cell. Up-regulation of Bmal-1 could reduce the cell death, oxidative stress, ferroptosis and activation of AKT/Nrf2 pathway at both ZT10 and ZT22 LPS administration. Conversely, its down-regulation presented opposite effects. AKT siRNA could weaken the effect of Bmal-1 pcDNA.

Conclusion

Ferroptosis presented the time of day-dependent manners via Bmal-1/AKT/Nrf2 in vivo and vitro models of SICM.

Molecular mechanisms of Sepsis attacking the immune system and solid organs

Remarkable progress has been achieved in sepsis treatment in recent times, the mortality rate of sepsis has experienced a gradual decline as a result of the prompt administration of antibiotics, fluid resuscitation, and the implementation of various therapies aimed at supporting multiple organ functions. However, there is still significant mortality and room for improvement. The mortality rate for septic patients, 22.5%, is still unacceptably high, accounting for 19.7% of all global deaths. Therefore, it is crucial to thoroughly comprehend the pathogenesis of sepsis in order to enhance clinical diagnosis and treatment methods. Here, we summarized classic mechanisms of sepsis progression, activation of signal pathways, mitochondrial quality control, imbalance of pro-and anti- inflammation response, diseminated intravascular coagulation (DIC), cell death, presented the latest research findings for each mechanism and identify potential therapeutic targets within each mechanism.

From immune dysregulation to organ dysfunction: understanding the enigma of Sepsis

Sepsis is a syndrome precipitated by immune dysregulation in response to infection, and represents a pivotal factor in global mortality attributed to diseases. The recent consensus delineates sepsis as a perilous state of organ dysfunction arising from the host's maladaptive reaction to infection. It masks the complexity and breadth of the immune mechanisms involved in sepsis, which is characterized by simultaneous hyperinflammation and immunosuppression. Sepsis is highly correlated with the dysregulation of immune response, which is mainly mediated by various immune cells and their interactions. This syndrome can lead to a plethora of complications, encompassing systemic inflammatory response, metabolic disturbances, infectious shock, MODS, and DIC. Furthermore, more research studies have been conducted on sepsis in the past few years. The pathological characteristics of sepsis have been improved or treated by targeting signaling pathways like NF-B, JAK-STAT, PI3K-Akt, and p38-MAPK. Combined drug therapy is better than single drug therapy for sepsis. This article will review the latest progress in the pathogenesis and treatment of sepsis.

Role and mechanisms of autophagy, ferroptosis, and pyroptosis in sepsis-induced acute lung injury

Sepsis-induced acute lung injury (ALI) is a major cause of death among patients with sepsis in intensive care units. By analyzing a model of sepsis-induced ALI using lipopolysaccharide (LPS) and cecal ligation and puncture (CLP), treatment methods and strategies to protect against ALI were discussed, which could provide an experimental basis for the clinical treatment of sepsis-induced ALI. Recent studies have found that an imbalance in autophagy, ferroptosis, and pyroptosis is a key mechanism that triggers sepsis-induced ALI, and regulating these death mechanisms can improve lung injuries caused by LPS or CLP. This article summarized and reviewed the mechanisms and regulatory networks of autophagy, ferroptosis, and pyroptosis and their important roles in the process of LPS/CLP-induced ALI in sepsis, discusses the possible targeted drugs of the above mechanisms and their effects, describes their dilemma and prospects, and provides new perspectives for the future treatment of sepsis-induced ALI.

STAT3-Mediated Ferroptosis is Involved in Sepsis-Associated Acute Respiratory Distress Syndrome

Sepsis-induced acute respiratory distress syndrome (ARDS) poses a grave danger to life, resulting from sepsis-induced multi-organ failure. Although ferroptosis, a form of iron-dependent lipid peroxidative cell death, has been associated with sepsis-induced ARDS, the specific mechanisms are not fully understood. In this study, we utilized WGCNA, PPI, friends analysis, and six machine learning techniques (Lasso, SVM, RFB, XGBoost, AdaBoost, and LightGBM) to pinpoint STAT3 as a potential diagnostic marker. A significant increase in monocyte and neutrophil levels was observed in patients with sepsis-induced ARDS, as revealed by immune infiltration analyses, when compared to controls. Moreover, there was a positive correlation between STAT3 expression and the level of infiltration. Single-cell analysis uncovered a notable disparity in B-cell expression between sepsis and sepsis-induced ARDS. Furthermore, in vitro experiments using LPS-treated human bronchial epithelial cells (BEAS-2B) and THP1 cells demonstrated a significant increase in STAT3 phosphorylation expression. Additionally, the inhibition of STAT3 phosphorylation by Stattic effectively prevented LPS-induced ferroptosis in both BEAS-2B and THP1 cells. This indicates that the activation of STAT3 phosphorylation promotes ferroptosis in human bronchial epithelial cells in response to LPS. In summary, this research has discovered and confirmed STAT3 as a potential biomarker for the diagnosis and treatment of sepsis-induced ARDS.

Intravenous calcitriol administration improves the liver redox status and attenuates ferroptosis in mice with high-fat diet-induced obesity complicated with sepsis

Obesity aggravates ferroptosis, and vitamin D (VD) may inhibit ferroptosis. We hypothesized that weight reduction and/or calcitriol administration have benefits against the sepsis-induced liver redox imbalance and ferroptosis in obese mice. Mice were fed a high-fat diet for 11 weeks, then half of the mice continued to consume the diet, while the other half were transferred to a low-energy diet for 5 weeks. After feeding the respective diets for 16 weeks, sepsis was induced by cecal ligation and puncture (CLP). Septic mice were divided into four experimental groups: OS group, obese mice injected with saline; OD group, obese mice with calcitriol; WS group, weight-reduction mice with saline; and WD group, weight-reduction mice with calcitriol. Mice in the respective groups were euthanized at 12 or 24 h after CLP. Results showed that the OS group had the highest inflammatory mediators and lipid peroxide levels in the liver. Calcitriol treatment reduced iron content, enhanced the reduced glutathione/oxidized glutathione ratio, upregulated nuclear factor erythroid 2-related factor 2, ferroptosis-suppressing protein 1, and solute carrier family 7 member 11 expression levels. Also, mitochondrion-associated nicotinamide adenine dinucleotide phosphate oxidase 1, peroxisome proliferator-activated receptor-γ coactivator 1, hypoxia-inducible factor-1α, and heme oxidase-1 expression levels increased in the late phase of sepsis. These results were not noted in the WS group. These findings suggest that calcitriol treatment elicits a more-balanced glutathione redox status, alleviates liver ferroptosis, and enhances mitochondrial biogenesis-associated gene expressions. Weight reduction alone had minimal influences on liver ferroptosis and mitochondrial biogenesis in obese mice with sepsis.

IDENTIFICATION OF A NOVEL SEPSIS PROGNOSIS MODEL: BASED ON TRANSCRIPTOME AND PROTEOME ANALYSIS

ABSTRACT

Sepsis is a highly prevalent and deadly disease. Currently, there is a lack of ideal biomarker prognostis models for sepsis. We attempt to construct a model capable of predicting the prognosis of sepsis patients by integrating transcriptomic and proteomic data. Through analysis of proteomic and transcriptomic data, we identified 25 differentially expressed genes (DEGs). Single-factor Cox-Lasso regression analysis identified 16 DEGs (overall survival-DEGs) associated with patient prognosis. Through multifactor Cox-Lasso regression analysis, a prognostic model based on these 16 genes was constructed. Kaplan-Meier survival analysis and receiver operating characteristic curve analysis were used to further validate the high stability and good predictive ability of this prognostic model with internal and external data. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of overall survival-DEGs and differentially expressed genes between high and low-risk groups based on the prognostic model revealed significant enrichment in immune-related pathways, particularly those associated with viral regulation.

Mitochondrial Damage in Sepsis

Mitochondria not only generate adenosine triphosphate (ATP) and act as the powerhouse of the cell but also contribute to host defense by producing reactive oxygen species. Therefore, mitochondrial damage in sepsis directly results in a shortage of energy currency and dysregulation of the immune system. Other than those, mitochondrial damage results in the release of highly dangerous mitochondrial DNA, facilitating acidosis by modulating the metabolism and inducing programmed cell death, thereby facilitating disease progression in sepsis. Various forms of cell death are induced by mitochondrial damage. Aponecrosis is a secondary conversion from apoptosis to necrosis. Although apoptosis is initially intended, it cannot be completed due to ATP depletion from mitochondrial damage, ultimately leading to inflammatory necrosis. Besides such accidental cell death, programmed inflammation-inducing cell deaths such as necroptosis, ferroptosis, and pyroptosis are induced by mitochondrial damage in sepsis. Based on these findings, the regulation of mitochondrial damage holds promise for the development of new therapeutic approaches for sepsis.

Evaluating the Causal Effects of Circulating Proteome on the Risk of Sepsis and Related Outcomes

The current investigation deployed Mendelian randomization (MR) to elucidate the causal relationship between circulating proteins and sepsis. A rigorous two-sample MR analysis evaluated the effect of plasma proteins on the sepsis susceptibility. To affirm the integrity of MR findings, a suite of supplementary analyses, including Bayesian colocalization, Steiger filtering, the assessment of protein-altering polymorphisms, and the correlation between expression quantitative trait loci and protein quantitative trait loci (pQTLs), was employed. The study further integrated the examination of protein-protein interactions and pathway enrichment, along with the identification of pharmacologically actionable targets, to advance our comprehension and outline potential sepsis therapies. Subsequent analyses leveraging cis-pQTLs within MR studies unveiled noteworthy relationships: 94 specific proteins exhibited significant links with sepsis-related 28 day mortality, while 96 distinct proteins correlated with survival outcomes in sepsis. Furthermore, incorporating both cis- and trans-pQTLs in MR investigations revealed more comprehensive findings, associating 201 unique proteins with sepsis-related 28 day mortality and 199 distinct proteins with survival outcomes in sepsis. Markedly, colocalization analyses confirmed that eight of these proteins exhibited prominent evidence for colocalization, emphasizing their potential criticality in sepsis pathophysiology. Further in silico analyses were conducted to delineate putative regulatory networks and to highlight prospective drug targets among these proteins. Employing the MR methodology has shed light on plasma proteins implicated in the etiopathogenesis of sepsis. This novel approach unveiled numerous biomarkers and targets, providing a scientific rationale for the development of new therapeutic strategies and prophylactic measures against sepsis.

Metallothionein Alleviates Glutathione Depletion-Induced Oxidative Cardiomyopathy through CISD1-Dependent Regulation of Ferroptosis in Murine Hearts

This study was designed to discern the effect of heavy scavenger metallothionein on glutathione (GSH) deprivation-evoked cardiac anomalies and mechanisms involved with an emphasis on ferroptosis. Wild-type and cardiac metallothionein transgenic mice received GSH synthase inhibitor buthionine sulfoximine (BSO; 30 mmol/L in drinking water) for 14 days before assessment of myocardial morphology and function. BSO evoked cardiac remodeling and contractile anomalies, including cardiac hypertrophy, interstitial fibrosis, enlarged left ventricular chambers, deranged ejection fraction, fraction shortening, cardiomyocyte contractile capacity, intracellular Ca2+ handling, sarcoplasmic reticulum Ca2+ reuptake, loss of mitochondrial integrity (mitochondrial swelling, loss of aconitase activity), mitochondrial energy deficit, carbonyl damage, lipid peroxidation, ferroptosis, and apoptosis. Metallothionein itself did not affect myocardial morphology and function, although it mitigated BSO-provoked myocardial anomalies, loss of mitochondrial integrity and energy, and ferroptosis. Immunoblotting revealed down-regulated sarco(endo)plasmic reticulum Ca2+-ATPase 2a, glutathione peroxidase 4, ferroptosis-suppressing CDGSH iron-sulfur domain 1 (CISD1), and mitochondrial regulating glycogen synthase kinase-3β phosphorylation with elevated p53, myosin heavy chain-β isozyme, IκB phosphorylation, and solute carrier family 7 member 11 (SLC7A11) as well as unchanged SLC39A1, SLC1A5, and ferroptosis-suppressing protein 1 following BSO challenge, all of which, except glutamine transporter SLC7A11 and p53, were abrogated by metallothionein. Inhibition of CISD1 using pioglitazone nullified GSH-offered benefit against BSO-induced cardiomyocyte ferroptosis and contractile and intracellular Ca2+ derangement. Taken together, these findings support a regulatory modality for CISD1 in the impedance of ferroptosis in metallothionein-offered protection against GSH depletion-evoked cardiac aberration.

Dysregulated dendritic cells in sepsis: functional impairment and regulated cell death

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Studies have indicated that immune dysfunction plays a central role in the pathogenesis of sepsis. Dendritic cells (DCs) play a crucial role in the emergence of immune dysfunction in sepsis. The major manifestations of DCs in the septic state are abnormal functions and depletion in numbers, which are linked to higher mortality and vulnerability to secondary infections in sepsis. Apoptosis is the most widely studied pathway of number reduction in DCs. In the past few years, there has been a surge in studies focusing on regulated cell death (RCD). This emerging field encompasses various forms of cell death, such as necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death (ADCD). Regulation of DC's RCD can serve as a possible therapeutic focus for the treatment of sepsis. Throughout time, numerous tactics have been devised and effectively implemented to improve abnormal immune response during sepsis progression, including modifying the functions of DCs and inhibiting DC cell death. In this review, we provide an overview of the functional impairment and RCD of DCs in septic states. Also, we highlight recent advances in targeting DCs to regulate host immune response following septic challenge.

Targeting novel regulated cell death：Ferroptosis, pyroptosis, and autophagy in sepsis-associated encephalopathy

Sepsis-associated encephalopathy (SAE), a common neurological complication of sepsis, is a heterogenous complex clinical syndrome caused by the dysfunctional response of a host to infection. This dysfunctional response leads to excess mortality and morbidity worldwide. Despite clinical relevance with high incidence, there is a lack of understanding for its both its acute/chronic pathogenesis and therapeutic management. A better understanding of the molecular mechanisms behind SAE may provide tools to better enhance therapeutic efficacy. Mounting evidence indicates that some types of non-apoptotic regulated cell death (RCD), such as ferroptosis, pyroptosis, and autophagy, contribute to SAE. Targeting these types of RCD may provide meaningful targets for future treatments against SAE. This review summarizes the core mechanism by which non-apoptotic RCD leads to the pathogenesis of SAE. We focus on the emerging types of therapeutic compounds that can inhibit RCD and delineate their beneficial pharmacological effects against SAE. Within this review we suggest that pharmacological inhibition of non-apoptotic RCD may serve as a potential therapeutic strategy against SAE.

GPX4, ferroptosis, and diseases

GPX4 (Glutathione peroxidase 4) serves as a crucial intracellular regulatory factor, participating in various physiological processes and playing a significant role in maintaining the redox homeostasis within the body. Ferroptosis, a form of iron-dependent non-apoptotic cell death, has gained considerable attention in recent years due to its involvement in multiple pathological processes. GPX4 is closely associated with ferroptosis and functions as the primary inhibitor of this process. Together, GPX4 and ferroptosis contribute to the pathophysiology of several diseases, including sepsis, nervous system diseases, ischemia reperfusion injury, cardiovascular diseases, and cancer. This review comprehensively explores the regulatory roles and impacts of GPX4 and ferroptosis in the development and progression of these diseases, with the aim of providing insights for identifying potential therapeutic strategies in the future.