The immunology of sepsis

To explore the influencing factors of clinical failure of anti-tumor necrosis factor-α (TNF-α) therapy in sepsis

Sepsis, a condition of significant clinical concern, is characterized by life-threatening organ dysfunction that arises from an infection and is exacerbated by a dysregulated host response. Targeting immune modulation, particularly against tumor necrosis factor-alpha (TNF-α), has emerged as a promising anti-inflammatory therapeutic strategy. However, approaches such as blood purification to eliminate inflammatory mediators or the use of anti-TNF-α therapies have shown limited efficacy in clinical practice. This literature review aims to elucidate the pathogenesis of sepsis and dissect the factors contributing to unfavorable outcomes in TNF-α-targeted treatments. Our analysis highlights several potential reasons for therapeutic failure. Complete blockade of TNF-α may adversely affect both TNFR1 and TNFR2 signaling, thereby reducing the efficacy of TNF-α inhibitors. Additionally, the complex heterogeneity of sepsis, including the etiology of infection, patient-specific factors (e.g., immune responsiveness, body mass index, and obesity), the development of anti-drug antibodies, and treatment duration, significantly influences therapeutic outcomes. Based on these insights, we emphasize the need for precision medicine in sepsis management. This includes stratifying patients into subgroups, using TNFR2 agonists or TNFR1-specific antagonists, refining drug design, implementing multi-target combination therapies, and considering the patient's physiological state at the time of treatment. Collectively, these strategies could enhance the efficacy of sepsis management. This review underscores the multifaceted nature of sepsis treatment and highlights the imperative for personalized, multimodal therapeutic approaches to improve clinical outcomes.

Interleukin-36β inhibits CD4+CD25+ regulatory T cells by activating endoplasmic reticulum-phagy in septic mice

BACKGROUND

CD4+CD25+ regulatory T cells (Tregs) contribute to the pathogenesis of sepsis-induced immunosuppression. We have identified interleukin (IL)-36β as a critical cytokine regulating CD4+CD25+ Treg activity.

METHODS

This study aimed to further investigate the underlying mechanism of IL-36β-triggered responses in murine CD4+CD25+ Tregs in presence of lipolysaccharide (LPS) and in a mouse model of sepsis induced by cecal and puncture (CLP).

RESULTS

Following LPS exposure, ER-phagy activity increased, peaked at 12 h, and then markedly declined. Furthermore, we observed that IL-36β could activate ER-phagy of CD4+CD25+ Tregs under LPS challenge. Mechanistic investigations revealed the critical involvement of the endoplasmic reticulum (ER) stress-related protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK)-activating transcription factor 4 (ATF4) signaling axis in IL-36β-induced ER-phagy. Moreover, IL-36β knockout (IL-36β-/-) strongly dampened ER-phagy and PERK-ATF4 signaling under LPS stimulation compared to the wild-type group. IL-36β-elicited effects on CD4+CD25+ Tregs were significantly abrogated by FAM134B (the ER-phagy-specific receptor) knockout or salubrinal (a specific inhibitor of the PERK-ATF4 pathway). In addition, IL-36β was potent in diminishing serum levels of creatinine (Cr), aspartate transaminase (AST), and alanine transaminase (ALT) and attenuated histopathologic alterations in the liver, kidneys, and lungs of CLP mice. Importantly, the absence of IL-36β notably aggravated the survival rate of septic mice, indicating a beneficial role in septic prognosis.

CONCLUSION

IL-36β can down-regulate the immune activity of CD4+CD25+ Tregs via ER-phagy induction. Our study might provide novel targets for therapeutic strategies to prevent the development of sepsis.

WHOLE TRANSCRIPTION ANALYSIS IDENTIFIED THE REGULATION OF HYPOXIA-INDUCIBLE FACTORS IN MONOCYTES WITH IMMUNE SUPPRESSION: IMPLICATIONS FOR CLINICAL OUTCOMES

ABSTRACT

Aims: Sepsis progression is marked by a complex immune response, where the involvement of hypoxia-inducible factors (HIFs) plays an uncertain role. The study aims to elucidate the involvement of HIF-1α in monocyte function during sepsis and its potential as a prognostic indicator. Methods and Results: Transcriptomic data from healthy individuals and septic patients in datasets GSE54514, GSE167363, and GSE46955 were analyzed. Additionally, human monocytes were employed to elucidate how HIF regulates immune responses in the context of sepsis. Septic nonsurvivors exhibited sustained upregulation of HIF-1α expression alongside compromised inflammatory response and antigen presentation, with downregulation of NF-κB and HLADRB1 genes associated with poor sepsis prognosis. Conversely, septic survivors displayed an increased proportion of classical monocytes and enhanced inflammation and expression of antigen presentation-related genes. During the recovery phase of sepsis, monocytes continued to demonstrate elevated HIF-1α expression. In cultured THP1 cells and septic CD14 + monocytes, HIF hindered inflammatory responses and antigen presentation, while also suppressing the proportion of classical monocytes after LPS stimulation. Mechanistically, HIF significantly attenuated LPS-induced immune responses in monocytes by inhibiting the phosphorylation of IKK. Conclusions: HIF in monocytes acts as a suppressor of immune-inflammatory responses and antigen presentation, and may serve as a negative molecular marker for sepsis development.

NINJ1: A NOVEL SEPSIS SEVERITY AND MORTALITY BIOMARKER

ABSTRACT

Background : Multiple cell death modalities are implicated in sepsis pathobiology. However, the clinical relevance of NINJ1, a key mediator of plasma membrane rupture during lytic cell death, in sepsis progression and outcomes has remained poorly explored. Methods: Circulating NINJ1 levels were measured in 116 septic intensive care unit (ICU) patients, 16 nonseptic ICU controls, and 16 healthy controls. Comparative analysis of serum NINJ1 across these groups was performed. Correlations between NINJ1 and clinical disease severity scores (Sequential Organ Failure Assessment [SOFA], Acute Physiology and Chronic Health Evaluation [APACHE II]) as well as laboratory parameters were examined in the sepsis cohort. Furthermore, we assessed the prognostic performance of NINJ1 for predicting 28-day mortality in septic patients using receiver operating characteristic (ROC) analyses. Results: Circulating NINJ1 levels were elevated in septic patients and positively correlated with sepsis severity scores. NINJ1 also showed positive correlations with liver injury markers (aspartate transaminase/alanine aminotransferase) and coagulation parameters (D-dimer, activated partial thromboplastin time, prothrombin time, thrombin time) in sepsis. Further analysis using the International Society on Thrombosis and Hemostasis overt disseminated intravascular coagulation scoring system revealed an association between NINJ1 and sepsis-induced coagulopathy. ROC analysis demonstrated that NINJ1 outperformed traditional inflammatory biomarkers procalcitonin and C-reactive protein in predicting 28-day sepsis mortality, although its prognostic accuracy was lower than SOFA and APACHE II scores. Combining NINJ1 with SOFA improved mortality prediction from an area under the curve of 0.6843 to 0.773. Conclusions: Circulating NINJ1 serves as a novel sepsis biomarker indicative of disease severity, coagulopathy and mortality risk, and its integration with SOFA and APACHE II scores substantially enhances prognostic risk stratification. These findings highlight the prospective clinical utility of NINJ1 for sepsis prognostication and monitoring, warranting further validation studies to facilitate implementation.

The roles of arginases and arginine in immunity

Arginase activity and arginine metabolism in immune cells have important consequences for health and disease. Their dysregulation is commonly observed in cancer, autoimmune disorders and infectious diseases. Following the initial description of a role for arginase in the dysfunction of T cells mounting an antitumour response, numerous studies have broadened our understanding of the regulation and expression of arginases and their integration with other metabolic pathways. Here, we highlight the differences in arginase compartmentalization and storage between humans and rodents that should be taken into consideration when assessing the effects of arginase activity. We detail the roles of arginases, arginine and its metabolites in immune cells and their effects in the context of cancer, autoimmunity and infectious disease. Finally, we explore potential therapeutic strategies targeting arginases and arginine.

Pathophysiology of Sepsis

Sepsis is a condition of life-threatening organ dysfunction caused by a dysregulated host response to infection. It is the result of a series of exaggerated physiologic responses that lead to simultaneous hyper- and hypoinflammatory states. In the hyperinflammatory phase, there is an exuberant release of cytokines, commonly referred to as a cytokine storm. The immune-suppressive phase is characterized by counterregulatory attempts to achieve homeostasis that sometimes "overshoot", leaving the host in a state of immunosuppression, thus predisposing to recurrent nosocomial and secondary infections. The aging population with comorbidities faces higher risks of immune dysfunction and inflammation. Thus, the number of sepsis survivors that develop subsequent infections is predicted to rise substantially in the next few decades. Understanding sepsis-induced immune dysregulation may enhance surveillance and outcomes. This review is intended to describe the pathophysiology of sepsis and its effects on the immune system.

A Self-Assembled Metabolic Regulator Reprograms Macrophages to Combat Cytokine Storm and Boost Sepsis Immunotherapy

Sepsis, a life-threatening inflammatory disorder characterized by multiorgan failure, arises from a dysregulated immune response to infection. Modulating macrophage polarization has emerged as a promising strategy to control sepsis-associated inflammation. The endogenous metabolite itaconate has shown anti-inflammatory potential by suppressing the stimulator of interferon genes (STING) pathway, but its efficacy is inhibited by hyperactive glycolysis, which sustains macrophage overactivation. Here, we revealed a critical crosstalk between the itaconate-STING axis and glycolysis in macrophage-mediated inflammation. Building on this interplay, we developed a novel nanoparticle LDO (lonidamine disulfide 4-octyl-itaconate), a self-assembled metabolic regulator integrating an itaconate derivative with the glycolysis inhibitor Lonidamine. By concurrently targeting glycolysis and STING pathways, LDO reprograms macrophages to restore balanced polarization. In sepsis models, LDO effectively attenuates CCL2-driven cytokine storms, alleviates acute lung injury, and significantly enhances survival via metabolic reprogramming. This study offers a cytokine-regulatory strategy rooted in immunometabolism, providing a foundation for the translational development of immune metabolite-based sepsis therapies.

Promote Sepsis Recovery through the Inhibition of Immunothrombosis via a Combination of Probenecid Nanocrystals and Cefotaxime Sodium

Sepsis is a life-threatening organ dysfunction syndrome caused by a dysregulated host immune response to pathogenic infection. Due to its high mortality rate, it has been a major global public health problem. Recent studies have shown that the formation of immunothrombosis plays as a "double-edged sword" in the pathogenesis of sepsis, and how to properly regulate immunothrombosis to avoid organ damage and end the high-inflammation state as early as possible are the key steps for sepsis therapy. Considering the complexity of sepsis therapy, the development of an effective combined therapeutic strategy is the goal of this study. First, the insoluble Panexin1 (Panx1) channel inhibitor probenecid (Prob) was prepared as nanocrystals and administered via intramuscular injection. At the same time, septic mice were intravenously injected with cefotaxime sodium through the tail vein for combination therapy. After treatment, the number of infection foci and the level of serum inflammatory factors in septic mice were significantly reduced, and also neutrophil NETosis was significantly inhibited; thus, the survival rate of septic mice was dramatically increased. Pathological analysis revealed that the combination treatment was safe and effective and could significantly reduce the formation of immunothrombosis in septic mice.

C-reactive protein to platelet ratio as an early biomarker in differentiating neonatal late-onset sepsis in neonates with pneumonia

Neonates with pneumonia (NWP) may experience unidentified life-threatening sepsis, yet distinguishing NWP from neonates with sepsis (NWS) based solely on clinical presentation remains challenging. This study aimed to evaluate the diagnostic utility of the C-reactive protein to platelet ratio (CPR) in distinguishing neonatal late-onset sepsis (LOS) among NWPs. From February 2016 to March 2022, a total of 1385 NWPs aged over 3 days were included. Of these, 174 neonates with confirmed positive blood cultures were categorized into the sepsis cohort, while the remainder formed the pneumonia cohort. All clinical data were retrospectively extracted from electronic medical records. CPR was calculated as the ratio of C-reactive protein levels to platelet count. Independent risk factors (IRFs) for neonatal LOS were identified through multivariate logistic regression. The diagnostic performance of CPR in identifying LOS among NWPs was analyzed using receiver operating characteristic (ROC) curve metrics. Statistical analyses were conducted using SPSS version 24.0 and MedCalc version 15.2.2. Neonates with NWS demonstrated significantly higher CPR compared to those with NWP alone. Further analysis revealed a notably increased incidence of sepsis among neonates exhibiting elevated CPR levels relative to those with lower values. Correlation analysis identified a direct association between CPR and elevated procalcitonin, creatinine, and urea nitrogen levels, as well as prolonged hospitalization. Multiple logistic regression analysis identified CPR as an IRF for late-onset NWS. ROC curve analysis demonstrated that CPR outperformed CRP and platelet count individually in diagnosing NWS, with a diagnostic sensitivity of 54% and specificity of 85%. CPR serves as an effective initial diagnostic marker with superior accuracy in distinguishing delayed NWS from NWP compared to CRP and platelet count alone.

Advances in sepsis research: Insights into signaling pathways, organ failure, and emerging intervention strategies

Sepsis is a complex syndrome resulting from an aberrant host response to infection. A hallmark of sepsis is the failure of the immune system to restore balance, characterized by hyperinflammation or immunosuppression. However, the net effect of immune system imbalance and the clinical manifestations are highly heterogeneous among patients. In recent years, research interest has shifted from focusing on the pathogenicity of microorganisms to the molecular mechanisms of host responses which is also associated with biomarkers that can help early diagnose sepsis and guide treatment decisions. Despite significant advancements in medical science, sepsis remains a major challenge in healthcare, contributing to substantial morbidity and mortality worldwide. Further research is needed to improve our understanding of this condition and develop novel therapies to improve outcomes for patients with sepsis. This review explores the related signal pathways of sepsis and underscores recent advancements in understanding its mechanisms. Exploration of diverse biomarkers and the emerging concept of sepsis endotypes offer promising avenues for precision therapy in the future.

Multi-omic studies on the pathogenesis of Sepsis

BACKGROUND

Sepsis is a life-threatening inflammatory condition, and its underlying genetic mechanisms are not yet fully elucidated. We applied methods such as Mendelian randomization (MR), genetic correlation analysis, and colocalization analysis to integrate multi-omics data and explore the relationship between genetically associated genes and sepsis, as well as sepsis-related mortality, with the goal of identifying key genetic factors and their potential mechanistic pathways.

METHODS

To identify therapeutic targets for sepsis and sepsis-related mortality, we conducted an MR analysis on 11,643 sepsis cases and 1,896 cases of 28-day sepsis mortality from the UK Biobank cohort. The exposure data consisted of 15,944 potential druggable genes (expression quantitative trait loci, eQTL) and 4,907 plasma proteins (protein quantitative trait loci, pQTL). We then performed sensitivity analysis, SMR analysis, reverse MR analysis, genetic correlation analysis, colocalization analysis, enrichment analysis, and protein-protein interaction network analysis on the overlapping genes. Validation was conducted using 17,133 sepsis cases from FinnGen R12. Drug prediction and molecular docking were subsequently used to further assess the therapeutic potential of the identified drug targets, while PheWAS was used to evaluate potential side effects. Finally, mediation analysis was conducted to identify the mediating role of related metabolites.

RESULTS

The MR analysis results identified a significant causal relationship between 24 genes and sepsis. The robustness of these causal associations was further strengthened by SMR analysis, sensitivity analysis, and reverse MR analysis. Genetic correlation analysis revealed that only two of these genes were genetically correlated with sepsis. Colocalization analysis showed that only one gene was closely associated with sepsis, while validation using the FinnGen dataset identified three genes. In the MR analysis of 28-day sepsis mortality, seven genes were found to have significant associations, with reverse MR analysis excluding one gene. The remaining genes passed sensitivity analysis, with no significant genes identified in genetic correlation and colocalization analyses. Molecular docking demonstrated excellent binding affinity between drugs and proteins with available structural data. PheWAS at the gene level did not reveal any potential side effects of the related drugs.

CONCLUSIONS

The identified drug targets, associated pathways, and metabolites have enhanced our understanding of the complex relationships between genes and sepsis. These genes and metabolites can serve as effective targets for sepsis treatment, paving new pathways in this field and laying a foundation for future research.

Haemoadsorption to remove inflammatory mediators in sepsis: past, present, and future

While a dysregulated immune response is at the center of the sepsis definition, standard care is still solely focussed on prompt administration of antimicrobial therapy, source control, resuscitation and organ supportive therapies. Extracorporeal blood purification therapies, such as haemoadsorption, have been proposed as a possible adjunctive therapy to standard care in sepsis. These adsorption devices aim to rebalance the dysregulated immune response by removal of excessive amounts of circulating inflammatory mediators, including cytokines and endotoxins. Thus far, the effects of haemoadsorption on clinical outcomes have been insufficiently studied and although its routine use is not justified based on the current evidence, multiple centers use these devices in patients with severe septic shock. This narrative review describes the most well-studied adsorption devices as well as a novel selective adsorption device called the 'IL-6-Sieve', including in vitro data showing its capturing potential. Finally, it addresses important considerations for future trials on haemoadsorption in septic patients.

Low levels of CD39+ Tregs may predict poor outcome in children with sepsis

OBJECTIVES

Sepsis is a life-threatening condition caused by a dysregulated immune response. This study aimed to explore immune dysregulation in pediatric sepsis and identify prognostic biomarkers for mortality prediction.

METHODS

Ninety-nine children with sepsis were followed for 28 days. Flow cytometry was used to analyze T cells, T-helper cells, B cells, natural killer (NK) cells, dendritic cells (DCs), and their subpopulations. Correlations between CD39+ regulatory T cells (Tregs), plasmacytoid DCs (pDCs), and transitional B cells with Phoenix Sepsis Score (PSS) were assessed. Receiver operating characteristic and Kaplan-Meier analyses were used to evaluate the prognostic value of CD39+ Tregs and pDCs. Cytokine levels were measured using a cytometric bead array.

RESULTS

CD39+ Tregs and transitional B cells were significantly lower in the nonsurvival and remote groups, while pDCs showed the opposite trend. CD39+ Tregs were negatively correlated with PSS, and pDCs were positively correlated. CD39+ Tregs below 12.45 % and pDCs above 0.96 % were both strong predictors of increased mortality risk. CD39+ Tregs maintained stable predictive performance within 72 h.

CONCLUSIONS

CD39+ Tregs and pDCs may serve as potential prognostic biomarkers in pediatric sepsis, with specific thresholds predicting increased mortality risk.

Inhibitory Immune Checkpoints Predict 7-Day, In-Hospital, and 1-Year Mortality of Internal Medicine Patients Admitted With Bacterial Sepsis

BACKGROUND

Sepsis is a life-threatening syndrome with complex pathophysiology and great clinical heterogeneity, which complicates the delivery of personalized therapies. Our goal was to demonstrate that some biomarkers identified as regulatory immune checkpoints in preclinical studies could guide the stratification of patients with sepsis into subgroups with shared characteristics of immune response or survival outcomes.

METHODS

We assayed the soluble counterparts of 12 biomarkers of immune response in 113 internal medicine patients with bacterial sepsis.

RESULTS

IL-1 receptor-associated kinase M (IRAK-M) exhibited the highest hazard ratios (HRs) for increased 7-day (1.94; 95% confidence interval [CI], 1.17-3.20) and 30-day mortality (1.61; 95% CI, 1.14-2.28). HRs of IRAK-M and galectin-1 for predicting 1-year mortality were 1.52 (95% CI, 1.20-1.92) and 1.64 (95% CI, 1.13-2.36), respectively. Patients with elevated serum levels of IRAK-M and galectin-1 had clinical traits of immune suppression and low survival rates.

CONCLUSIONS

Two inhibitory immune checkpoint biomarkers (IRAK-M and galectin-1) helped identify 3 distinct sepsis phenotypes with distinct prognoses. These biomarkers shed light on the interplay between immune dysfunction and prognosis in patients with bacterial sepsis and may prove to be useful prognostic markers, therapeutic targets, and biochemical markers for targeted enrollment in therapeutic trials.

Markers of Hemophagocytic Lymphohistiocytosis Are Associated with Mortality in Critically Ill Patients

Background: Critically ill patients often display systemic immune dysregulation and increased inflammatory activity. Hemophagocytic lymphohistiocytosis (HLH) represents a rare syndrome defined by the inappropriate survival of cytotoxic T cells and the occurrence of cytokine storms. Although HLH is characterized by relatively high mortality rates, little is known about the predictive value of its diagnostic criteria. Accordingly, our objective was to evaluate these properties within an unselected cohort of critically ill patients admitted to a tertiary intensive care unit (ICU). Methods: This single-center prospective observational study included 176 consecutive patients. Available HLH criteria at admission were assessed, including sCD25 measurements performed using ELISA. Results: Overall, 30-day mortality rates were significantly higher in patients exhibiting two or more criteria of HLH (21.9% vs. 43.3%, p = 0.033). Moreover, sCD25 emerged as an independent risk predictor of 30-day mortality independent of age, sex, the use of vasopressors, and mechanical ventilation (HR 2.72 for the highest tertile vs. lowest tertile, p = 0.012). Additionally, fibrinogen was significantly decreased in non-survivors (p = 0.019), and its addition to the SAPS II score significantly increased its prognostic capability (p = 0.045). In contrast, ferritin and triglyceride levels were not different in survivors versus non-survivors. Conclusions: Critically ill patients displaying two or more HLH criteria exhibit a dramatic increase in 30-day mortality, even in the absence of an established HLH diagnosis. Furthermore, elevated levels of sCD25 and decreased levels of fibrinogen were found to be significant predictors of mortality.

Intracellular methylglyoxal accumulation in classically activated mouse macrophages is mediated by HIF-1α

Approximately one million cases of sepsis in the United States occur annually. The early phase of sepsis features dramatic changes in host metabolism and inflammation. While examining the effects of metabolic pathways on inflammation, we discovered that the highly reactive glycolytic metabolite, methylglyoxal (MG), accumulates intracellularly during classical activation of macrophages. Herein, we explored the role of glycolysis and the master regulator of glycolysis, Hypoxia-Inducing Factor-1α (HIF-1α), in inflammation and MG accumulation in mouse and human macrophages. To determine how HIF-1α regulates the inflammatory response of macrophages, we correlated HIF-1α stabilization with proinflammatory gene expression and MG-adduct accumulation in WT vs HIF1a-deficient macrophages treated with LPS or LPS + IFN-γ. A nearly complete loss of HIF-1α protein expression in response to the hypoxia mimetic, cobalt chloride, confirmed the phenotype of the HIF1a-deficient macrophages. Moreover, absence of HIF-1α was also associated with decreased MG accumulation. Increasing the glucose concentration in cultured macrophages was sufficient to cause accumulation of endogenous MG-adducts which correlated with increased Tnf and Il1b expression during classical activation. The use of the MG antagonist, aminoguanidine, led to a significant decrease in Tnf and Il1b expression in both mouse macrophages and the THP-1 human macrophage cell line. Although off-target effects cannot be ruled out, these results are consistent with the possibility that MG regulates cytokine expression in classically activated macrophages. Collectively, this work suggests that HIF-1α stabilization is upstream of MG accumulation and that targeting the activity of HIF-1α in macrophages may be therapeutic during sepsis by limiting endogenous MG accumulation.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2024

The 2024 revised edition of the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock (J-SSCG 2024) is published by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine. This is the fourth revision since the first edition was published in 2012. The purpose of the guidelines is to assist healthcare providers in making appropriate decisions in the treatment of sepsis and septic shock, leading to improved patient outcomes. We aimed to create guidelines that are easy to understand and use for physicians who recognize sepsis and provide initial management, specialized physicians who take over the treatment, and multidisciplinary healthcare providers, including nurses, physical therapists, clinical engineers, and pharmacists. The J-SSCG 2024 covers the following nine areas: diagnosis of sepsis and source control, antimicrobial therapy, initial resuscitation, blood purification, disseminated intravascular coagulation, adjunctive therapy, post-intensive care syndrome, patient and family care, and pediatrics. In these areas, we extracted 78 important clinical issues. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 42 GRADE-based recommendations, 7 good practice statements, and 22 information-to-background questions were created as responses to clinical questions. We also described 12 future research questions.

S100A9 in sepsis: A biomarker for inflammation and a mediator of organ damage

Sepsis is the body's response to infection, which can result in multiple organ failure. The immune imbalance in patients with sepsis leads to high mortality. Recent research has greatly advanced our understanding of sepsis pathophysiology, especially in the regulation of inflammatory pathways and immune suppression. S100A9, an alarmin, plays a critical role in modulating the immune response during sepsis and is associated with the potential for multiple organ dysfunction. In the early stage of sepsis, S100A9 can represent the occurrence of inflammation, while in the late stage of sepsis, S100A9 is related to immune suppression. This review summarizes the latest developments in S100A9 research, including its biological functions, role in immune responses, effects on organ damage across different systems during sepsis, and potential clinical applications. It provides insights into the interactions between S100A9 and the immune response and explores S100A9's involvement in sepsis-associated organ injuries. Additionally, this review outlines a framework for future applications of targeted S100A9 interventions and therapeutic strategies to reduce organ injury in sepsis.

Interaction, diagnosis, and treatment of lung microbiota-NLRP3 inflammasome-target organ axis in sepsis

Sepsis is defined as a life-threatening condition caused by a dysregulated host response to infection, leading to multi-organ dysfunction, and representing a significant global health burden. The progression of sepsis is closely linked to disruptions in lung microbiota, including bacterial translocation, impaired barrier function, and local microenvironmental disturbances. Conversely, the worsening of sepsis exacerbates lung microbiota imbalances, contributing to multi-organ dysfunction. Recent culture-independent microbiological techniques have unveiled the complexity of the respiratory tract microbiome, necessitating a reassessment of the interactions between the host, microbes, and pathogenesis in sepsis. This review synthesizes current insights into the causes of microbiota dysbiosis and the regulatory mechanisms of the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, as well as their interactions during sepsis and sepsis-induced organ dysfunction. In addition, we summarize novel diagnostic and therapeutic approaches from the current study that may offer promising prospects for the management of sepsis.

Sepsis and high-density lipoproteins: Pathophysiology and potential new therapeutic targets

In 2020, sepsis has been defined a worldwide health major issue (World Health Organization). Lung, urinary tract and abdominal cavity are the preferred sites of sepsis-linked infection. Research has highlighted that the advancement of sepsis is not only related to the presence of inflammation or microbial or host pattern recognition. Clinicians and researchers now recognized that a severe immunosuppression is also a common feature found in patients with sepsis, increasing the susceptibility to secondary infections. Lipopolysaccharides (LPS) are expressed on the cell surface of Gram-negative, whereas Gram-positive bacteria express peptidoglycan (PGN) and lipoteichoic acid (LTA). The main mechanism by which LPS trigger host innate immune responses is binding to TLR4-MD2 (toll-like receptor4-myeloid differentiation factor 2), whereas, PGN and LTA are exogenous ligands of TLR2. Nucleotide-binding oligomerization domain (NOD)-like receptors are the most well-characterized cytosolic pattern recognition receptors, which bind microbial molecules, endogenous by-products and environmental triggers. It has been demonstrated that high-density lipoproteins (HDL), besides their major role in promoting cholesterol efflux, possess diverse pleiotropic properties, ranging from a modulation of the immune system to anti-inflammatory, anti-apoptotic, and anti-oxidant functions. In addition, HDL are able at i) binding LPS, preventing the activating of TLR4, and ii) inducing the expression of ATF3 (Activating transcription factor 3), a negative regulator of the TLR signalling pathways, contributing at justifying their capacity to hamper infection-based illnesses. Therefore, reconstituted HDL (rHDL), constituted by apolipoprotein A-I/apolipoprotein A-IMilano complexed with phospholipids, may be considered as a new therapeutic tool for the management of sepsis.

The Role of Yes-Associated Protein in Inflammatory Diseases and Cancer

Yes-associated protein (YAP) plays a central role in the Hippo pathway, primarily governing cell proliferation, differentiation, and apoptosis. Its significance extends to tumorigenesis and inflammatory conditions, impacting disease initiation and progression. Given the increasing relevance of YAP in inflammatory disorders and cancer, this study aims to elucidate its pathological regulatory functions in these contexts. Specifically, we aim to investigate the involvement and molecular mechanisms of YAP in various inflammatory diseases and cancers. We particularly focus on how YAP activation, whether through Hippo-dependent or independent pathways, triggers the release of inflammation and inflammatory mediators in respiratory, cardiovascular, and digestive inflammatory conditions. In cancer, YAP not only promotes tumor cell proliferation and differentiation but also modulates the tumor immune microenvironment, thereby fostering tumor metastasis and progression. Additionally, we provide an overview of current YAP-targeted therapies. By emphasizing YAP's role in inflammatory diseases and cancer, this study aims to enhance our understanding of the protein's pivotal involvement in disease processes, elucidate the intricate pathological mechanisms of related diseases, and contribute to future drug development strategies targeting YAP.

Dynamic Immune Indicator Changes as Predictors of ARDS in ICU Patients with Sepsis: A Retrospective Study

Background

Understanding the dynamic changes in immune indicators during sepsis and their predictive value for Acute respiratory distress syndrome (ARDS) is crucial for improving patient outcomes.

Methods

This single-center, observational retrospective study was conducted at Lishui Central Hospital, Zhejiang Province. Patients diagnosed with Sepsis-3 were categorized into non-ARDS and ARDS groups based on ARDS development. Data collection included demographics, clinical data, and immune parameters. Immune parameters were collected on days 1, 3, and 7 post-admission. Multivariate logistic regression analysis identified independent risk factors for ARDS, and a nomogram model was constructed. The predictive ability of the model was evaluated using ROC curves.

Results

Multivariate analysis identified key factors for the nomogram, including CD4, CD8, Treg, lymphocyte, IgG, and IgA levels on Days 3 and 7. On Day 3, CD8 (P < 0.001), Tregs (P = 0.021), IgG (P < 0.001), and IgA (P < 0.001) showed significant negative correlations with ARDS development. On Day 7, CD4 (P < 0.001), CD8 (P < 0.001), lymphocyte count (P < 0.001), and IgA (P < 0.001) similarly demonstrated significant negative correlations with ARDS risk. The nomogram model had an AUC of 0.998 (95% CI: 0.997-0.999), indicating high predictive ability.

Conclusion

Early dynamic changes in immune indicators, including CD8, CD4, Treg, IgA, IgG, and Lymphocyte, predict ARDS development in ICU sepsis patients.

PROGNOSTIC IMPLICATIONS OF CHANGES IN PLATELET TRAJECTORIES IN PATIENTS WITH SEPSIS: A RETROSPECTIVE ANALYSIS USING THE MEDICAL INFORMATION MART FOR INTENSIVE CARE IV DATABASE

ABSTRACT

Objective: Patients with sepsis often experience reductions or increases in platelet counts, but the implications of these temporal patterns on prognosis remain unclear. The aim of this study was to investigate the impact of changes in platelet trajectories on the clinical prognosis of sepsis. Methods: This study was a retrospective analysis using data from the Medical Information Mart for Intensive Care IV database. Patients with sepsis were identified from the database, and their platelet trajectories were categorized into four distinct models based on the changes in platelet counts over a period of 14 days after diagnosis of sepsis. The effect of these trajectories on patient prognosis was subsequently evaluated. Results: A total of 15,250 patients with sepsis were included to construct a model, and the following four distinct platelet count trajectories were identified: normal platelet levels (phenotype 1); persistently low platelet levels (phenotype 2); gradually increasing platelet levels exceeding the normal range (phenotype 3); and consistently significantly elevated platelet levels (phenotype 4). Statistically significant differences were found in the 28-day mortality, in-hospital mortality, and 90-day mortality among the four phenotypes. Multivariate regression analysis showed that compared to the group with normal platelet levels (phenotype 1), the group with persistently low platelet levels (phenotype 2) had higher in-hospital mortality (odds ratio [OR] = 1.34, 95% confidence interval [CI]: 1.16-1.54), 28-day mortality (OR = 1.69, 95% CI: 1.47-1.94), and 90-day mortality (OR = 1.50, 95% CI: 1.32-1.69). There was no difference in in-hospital mortality between phenotypes 3 and 4 compared to phenotype 1, although phenotype 4 showed an increase in 28-day mortality ( P < 0.05), and phenotype 3 showed a decreasing trend in 90-day mortality ( P < 0.05). The results of inverse probability weighting adjusted by regression were basically consistent with the above findings, except that there was no statistical difference in 28-day mortality between phenotype 4 and phenotype 1. In the subgroups based on age, weight, and antiplatelet drugs or therapies, there was an interaction between platelet levels and these factors. Conclusions: In patients with sepsis, a decrease in platelet count is associated with increased mortality, while a moderate increase in platelet count can reduce 90-day mortality. However, for patients with persistently elevated platelet counts, caution is advised when using antiplatelet drugs or therapies, as it may increase mortality.

Unraveling the immunological landscape and gut microbiome in sepsis: a comprehensive approach to diagnosis and prognosis

BACKGROUND

Comprehensive and in-depth research on the immunophenotype of septic patients remains limited, and effective biomarkers for the diagnosis and treatment of sepsis are urgently needed in clinical practice.

METHODS

Blood samples from 31 septic patients in the Intensive Care Unit (ICU), 25 non-septic ICU patients, and 18 healthy controls were analyzed using flow cytometry for deep immunophenotyping. Metagenomic sequencing was performed in 41 fecal samples, including 13 septic patients, 10 non-septic ICU patients, and 18 healthy controls. Immunophenotype shifts were evaluated using differential expression sliding window analysis, and random forest models were developed for sepsis diagnosis or prognosis prediction.

FINDINGS

Septic patients exhibited decreased proportions of natural killer (NK) cells and plasmacytoid dendritic cells (pDCs) in CD45+ leukocytes compared with non-septic ICU patients and healthy controls. These changes statistically mediated the association of Bacteroides salyersiae with sepsis, suggesting a potential underlying mechanism. A combined diagnostic model incorporating B.salyersia, NK cells in CD45+ leukocytes, and C-reactive protein (CRP) demonstrated high accuracy in distinguishing sepsis from non-sepsis (area under the receiver operating characteristic curve, AUC = 0.950, 95% CI: 0.811-1.000). Immunophenotyping and disease severity analysis identified an Acute Physiology and Chronic Health Evaluation (APACHE) II score threshold of 21, effectively distinguishing mild (n = 19) from severe (n = 12) sepsis. A prognostic model based on the proportion of total lymphocytes, Helper T (Th) 17 cells, CD4+ effector memory T (TEM) cells, and Th1 cells in CD45+ leukocytes achieved robust outcome prediction (AUC = 0.906, 95% CI: 0.732-1.000), with further accuracy improvement when combined with clinical scores (AUC = 0.938, 95% CI: 0.796-1.000).

INTERPRETATION

NK cell subsets within innate immunity exhibit significant diagnostic value for sepsis, particularly when combined with B. salyersiae and CRP. In addition, T cell phenotypes within adaptive immunity are correlated with sepsis severity and may serve as reliable prognostic markers.

FUNDING

This project was supported by the National Key R&D Program of China (2023YFC2307600, 2021YFA1301000), Shanghai Municipal Science and Technology Major Project (2023SHZDZX02, 2017SHZDZX01), Shanghai Municipal Technology Standards Project (23DZ2202600).

D 4 -CHIP REVEALS IMPAIRED T-CELL FUNCTION IN SEPSIS: INSIGHTS FROM PLASMA MICROENVIRONMENT ANALYSIS AND MITOCHONDRIAL-TARGETED THERAPY

ABSTRACT

Background: Sepsis, a systemic inflammation syndrome initiated by infection, poses significant challenges due to its intricate pathophysiology. T cells play a crucial role in combating infections during sepsis. Despite previous observations indicating T-cell dysfunction in sepsis, reliable in vitro detection methods were lacking, and the factors influencing these impairments remained unclear. Methods: We developed a novel method using the D 4 -Chip to assess sepsis T-cell migration function. This microfluidic platform enabled precise analysis of migration function under controlled conditions. Additionally, We explored the impact of the plasma microenvironment on T-cell behavior, along with the redox environment in sepsis, and assessed the potential efficacy of Mitoquinone mesylate (MitoQ), a mitochondrial-targeted drug. Results: Our findings revealed impaired migration function in sepsis T cells compared to healthy controls. Interestingly, sepsis plasma enhanced the migration of healthy T cells, yet incubation with healthy plasma did not fully restore migration impairments in sepsis T cells. Subsequent investigations uncovered a significant increase in NADH/NAD+ levels in sepsis T cells, with healthy T cells exposed to various sepsis plasma conditions also showing elevated NADH/NAD+ levels. Importantly, MitoQ normalized abnormal intracellular NADH/NAD+ levels and enhanced the migration ability of T cells. Conclusions: Short-term incubation with sepsis plasma does not directly inhibit T-cell migration but instead affects T-cell function by disrupting the intracellular redox environment. Improving the intracellular redox environment of sepsis patients contributes to restoring impaired migration and proliferation, with MitoQ demonstrating therapeutic potential.

The Protective Effect of Octanoic Acid on Sepsis: A Review

Sepsis, a systemic inflammation that occurs in response to a bacterial infection, is a significant medical challenge. Research conducted over the past decade has indicated strong associations among a patient's nutritional status, the composition of their gut microbiome, and the risk, severity, and prognosis of sepsis. Octanoic acid (OA) plays a vital role in combating sepsis and has a protective effect on both animal models and human patients. In this discussion, the potential protective mechanisms of OA in sepsis, focusing on its regulation of the inflammatory response, immune system, oxidative stress, gastrointestinal microbiome and barrier function, metabolic disorders and malnutrition, as well as organ dysfunction are explored. A comprehensive understanding of the mechanisms by which OA act may pave the way for new preventive and therapeutic approaches to sepsis.

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.

Association Between Plasma Granzyme B Levels, Organ Failure, and 28-Day Mortality Prediction in Patients with Sepsis

Background/Objectives: Sepsis is basically an inflammatory disease that involves the host's immune response. Granzyme B, a cytotoxic protease, has garnered attention for its involvement in modulating immune responses. This study aimed to elucidate the clinical implications of granzyme B in critically ill patients with sepsis, focusing on plasma granzyme B levels as a potential prognostic marker. Methods: We conducted a retrospective analysis of sequentially collected blood samples from 57 sepsis patients admitted to the medical intensive care unit at Severance Hospital, a tertiary hospital in Seoul, South Korea. Clinical and laboratory data were comparatively analyzed between 28-day survivors and nonsurvivors. Results: The number of patients in the survivor and nonsurvivor groups was 32 (56.1%) and 25 (43.9%), respectively. Compared to survivors, nonsurvivors had higher APACHE II (23.5 vs. 34, p = 0.007) and SOFA (10 vs. 15, p = 0.001) scores, as well as increased levels of serum lactate (1.8 vs. 9.2 mmol/L, p < 0.001) and plasma granzyme B (28.2 vs. 71 pg/mL, p < 0.001). Granzyme B exhibited a robust area under the receiving operating characteristic (AUROC) for predicting 28-day mortality (AUROC = 0.794), comparable to lactate (0.804), SOFA (0.764), and APACHE II (0.709). The combined index of lactate and granzyme B demonstrated the highest AUROC (0.838) among all investigated predictors. Significant positive correlations were observed between log granzyme B and various inflammatory cytokines, including log IFN-γ (r = 0.780), IL-4 (r = 0.540), IL-10 (r = 0.534), and IL-6 (r = 0.520). Conclusions: Plasma granzyme B demonstrated fair short-term mortality prediction among patients admitted to the ICU, suggesting its potential utility for risk stratification and managing patients with sepsis.

Programmed cell death markers in COVID-19 survivors with and without sepsis

Introduction

Sepsis remains a leading cause of mortality, especially in COVID-19 patients, due to delayed diagnosis and limited therapeutic options. While the mechanisms of programmed cell death (PCD) in COVID-19 and sepsis are complex, understanding the molecular markers involved in these processes may aid in assessing disease severity. This study aimed to investigate the roles of PCD markers, inflammatory cytokines, and MHC molecules in distinguishing disease severity in COVID-19 patients with and without sepsis.

Methods

The study involved adult patients (≥18 years) who survived COVID-19, grouped into four cohorts: COVID-19 with sepsis (C19wSepsis), COVID-19 without sepsis (C19NoSepsis), sepsis alone, and healthy controls. Serum and peripheral blood mononuclear cells (PBMCs) from each cohort were analyzed using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. PCD markers (caspase-3, caspase-1, MLKL, LC3B, p62/SQSTM1), inflammatory cytokines (IL-1-beta, IFN-gamma), and MHC molecules (MHC I-A, MHC II-DRB1) were assessed. Statistical analyses were performed to evaluate differences in marker levels between and within cohorts.

Results

The analysis identified two distinct molecular signatures associated with disease severity. The first signature, characterized by elevated levels of secreted markers of PCD, IL-1-beta, IFN-gamma, MHC I-A and MHC II-DRB1, was common to the C19wSepsis and C19NoSepsis cohorts. The second signature, which was more prominent in the cellular markers of PCD (caspase-1, caspase-3, MLKL, p62/SQSTM1), was uniquely associated with the C19wSepsis cohort.

Conclusion

These findings provide insight into the molecular signatures distinguishing immune responses in COVID-19-related sepsis and may serve as valuable biomarkers for assessing disease severity, while guiding therapeutic interventions in critical care settings.

Polyethyleneimine/fucoidan polyplexes as vaccine carriers for enhanced antigen loading and dendritic cell activation

Vaccination is one of the most effective strategies for preventing infectious diseases. Recently, most research has centered on the development of protein subunit vaccines due to their safety. However, their low immunogenicity remains a challenge. Nanoparticle vaccines offer advantages by protecting proteins from degradation and acting as adjuvants to stimulate the immune system. Herein, a polyplexe (OVA@PEI/Fu) formed by the electrostatic interaction between positively charged polyethyleneimine (PEI) and negatively charged fucoidan was prepared for the encapsulation of a model antigen, ovalbumin (OVA). Experimental results revealed that the incorporation of fucoidan in the polyplexes not only enhanced OVA loading efficiency but also contributed adjuvant effects, significantly boosting dendritic cell activation and maturation in vitro compared to OVA@PEI polyplexes. In vivo experiments showed that the OVA@PEI/Fu can induce strong anti-OVA specific antibody responses, as well as OVA-specific CD4+ and CD8+ T cell responses. The carrier developed in the present study shows promise as a platform for protein-based subunit vaccines.

Comparison Between Signal Transduction Pathway Activity in Blood Cells of Sepsis Patients and Laboratory Models

Sepsis represents a serious disease burden that lacks effective treatment. Drug development for sepsis requires laboratory models that adequately represent sepsis patients. Simultaneous Transcriptome-based Activity Profiling of Signal Transduction Pathway (STAP-STP) technology quantitatively infers STP activity from mRNA levels of target genes of the STP-associated transcription factor. Here, we used STAP-STP technology to compare STP activities between sepsis patients and lipopolysaccharide (LPS)-based models. Activity scores of Androgen Receptor (AR), TGFβ, NFκB, JAK-STAT1/2, and JAK-STAT3 STPs were calculated based on publicly available transcriptome data. Peripheral blood mononuclear cells (PBMCs) from patients with Gram-negative sepsis, nor PBMCs stimulated with LPS in vitro, showed altered STP activity. Increased NFκB, JAK-STAT1/2, and JAK-STAT3 STP activity was found in whole blood stimulated with LPS in vitro, and in whole blood obtained after intravenous injection of LPS in humans in vivo; AR and TGFβ STP activity only increased in the in vivo LPS model. These results resembled previously reported STP activity in whole blood of sepsis patients. We provide the first comparison of STP activity between patients with sepsis and laboratory model systems. Results are of use for the refinement of sepsis model systems for rational drug development.

Panax notoginseng saponins ameliorate LPS-induced acute lung injury by promoting STAT6-mediated M2-like macrophage polarization

BACKGROUND

Acute lung injury (ALI) is a severe inflammatory condition characterized by dysregulated immune responses and high mortality rates, with limited effective therapeutic options currently available. Panax notoginseng saponins (PNS), bioactive compounds derived from Panax notoginseng, have shown promise in mitigating lipopolysaccharide (LPS)-induced ALI. However, the molecular mechanisms underlying their therapeutic effects remain poorly understood. Given the critical role of M2-like macrophage polarization in resolving inflammation and promoting tissue repair, we investigated whether PNS exerts its protective effects in ALI by modulating this process. Furthermore, we explored the specific involvement of the signal transducer and activator of transcription 6 (STAT6) pathway in mediating these effects.

METHODS

Chemical profiling of PNS was performed using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), followed by quantitative analysis of its major bioactive components via high-performance liquid chromatography (HPLC). To evaluate the therapeutic efficacy of PNS and its principal constituents, we established an ALI mouse model through intratracheal administration of LPS. Comprehensive assessments included lung field shadowing, oxygen saturation levels, pulmonary function, and systematic histopathological examination. The regulatory effects of PNS on macrophage polarization were examined in THP-1 cells and bone marrow-derived macrophages (BMDMs), with cellular phenotypes analyzed by flow cytometry. To elucidate the mechanistic role of STAT6 in PNS-mediated protection, experiments were conducted using Stat6-deficient BMDMs and Stat6 knockout mice.

RESULTS

UPLC-Q-TOF-MS and HPLC identified and quantified the principal components of PNS: Notoginsenoside R1, Ginsenoside Rg1, Ginsenoside Re, and Ginsenoside Rb1. PNS treatment dose-dependently reduced inflammatory responses in LPS-induced ALI mice, as evidenced by decreased cytokine levels. Each of the four major PNS components independently alleviated ALI symptoms in mice. Pathway analysis revealed 56 potential ALI-related targets, with Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment suggesting that PNS exerts its protective effects by modulating inflammatory signaling pathways. In vitro studies demonstrated that PNS promoted STAT6 phosphorylation and nuclear translocation, enhancing M2-like macrophage polarization and interleukin-10 (IL-10) secretion in a STAT6-dependent manner. Genetic ablation of Stat6 partially reversed the protective effects of PNS on ALI, macrophage polarization, and IL-10 production, confirming the pivotal role of STAT6 in mediating PNS activity.

CONCLUSION

This study demonstrates that PNS alleviates LPS-induced ALI by promoting STAT6-dependent M2-like macrophage polarization, highlighting its potential as a therapeutic agent for ALI. These findings provide mechanistic insights into the anti-inflammatory actions of PNS and underscore the importance of STAT6 signaling in its protective effects.

Effects of neutrophil granule proteins on sepsis-associated lymphopenia and their relationship with CD4+ T-cell pyroptosis

Background

Neutrophil acts as a double-edged sword in the immune system. We hypothesized that an elevated neutrophil granule protein level is associated with sepsis-associated lymphopenia (SAL).

Methods

We enrolled 61 patients with sepsis admitted to the Department of Critical Care Medicine of Peking Union Medical College Hospital between May 2022 and October 2023 in this study. Clinical and immunological parameters were recorded. Levels of neutrophil granule proteins, including myeloperoxidase (MPO) and neutrophil elastase (NE), and pyroptosis factors were examined.

Results

Levels of neutrophil granule proteins (MPO, 82.9 vs. 175.3, p < 0 <.0001; NE, 56.3 vs. 144.2, p < 0.0001) were significantly higher in patients with sepsis with lymphopenia. Neutrophil granule protein levels were independently associated with SAL risk (MPO: OR = 1.0841, 95% CI, 1.0020-1.1730; NE: OR = 1.0540, 95% CI, 1.0040-1.1065). The area under the curve of MPO levels predicting SAL occurrence was 0.939 (95% CI, 0.846-0.984), and that of NE was 0.950 (95% CI, 0.862-0.989). Furthermore, neutrophil granule proteins were significantly correlated with CD4+ T cell and its pyroptosis [MPO and CD4+ T cells (r = -0.4039, p < 0.0001), CD4+NLRP3 (r = 0.4868, p < 0.0001), NE and CD4+ T cells (r = -0.5140, p < 0.0001), and CD4+NLRP3 (r = 0.6513, p < 0.0001)].

Conclusion

Increased levels of neutrophil granule proteins were significantly associated with SAL incidence, and a significant relationship between neutrophil granule proteins and the pyroptosis pathway of CD4+ T cells was revealed.

Clinical trial registration

chictr.org.cn identifier ChiCTR-ROC-17010750.

Genetic analysis of diagnostic and therapeutic potential for ferroptosis in postoperative sepsis

BACKGROUND

Ferroptosis is a new form of iron-dependent cell death that is closely associated with sepsis. However, few studies have investigated the diagnostic and therapeutic potential for ferroptosis-related genes (FRGs) among postoperative sepsis.

METHODS

The GSE131761 dataset was used to identify differentially expressed FRGs (DE-FRGs). KEGG and GO analyses were subsequently performed. LASSO and SVM-RFE methods were applied for identifying genetic biomarkers for sepsis. Gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were applied for exploring the biological properties of the DEGs. CIBERSORT was applied to analyse immune cell infiltration. DGldb was employed for predicting potential target drugs for the DEGs. Competing endogenous RNA (ceRNA) networks were constructed to analyse the regulatory patterns of the DEGs. The expression of hub genes was validated based on GSE26440 dataset. The bioinformatics analysis was carried out with R software (version 4.1.2). Blood from sepsis patients and healthy controls was collected and the expression of hub genes was experimentally verified by real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

38 sepsis-associated DE-FRGs were assessed via Gene Expression Omnibus (GEO) and Ferroptosis database (FerrDb), and the gene function analysis showed that they were closely related to inflammatory response and autophagy regulation. Subsequently, SVM-RFE and LASSO methods determined 7 marker genes. GSEA suggested that these marker genes may be involved in regulating several biological pathways. Furthermore, 52 gene-targeted drugs were identified in this study, the vast majority of which were associated with MAPK14. CIBERSORT analysis suggested that SLC38A1, MGST1, and MAPK14 may be involved in immune microenvironment alterations. We revealed the potential complex regulatory relationship by constructing a ceRNA network based on marker genes. Finally, 6 genes were validated in the validation set, with 5 of them further confirmed through RT-qPCR.

CONCLUSION

Seven genes associated with ferroptosis are screened from postoperative sepsis samples. The expression of these genes has high diagnostic validity for sepsis and may serve as potential diagnostic biomarkers. This study gives an entrance point to uncover the underlying mechanisms of sepsis.

Soluble CD72 concurrently impairs T cell functions while enhances inflammatory response in sepsis

BACKGROUND

Sepsis is defined as multi-organ dysfunction caused by dysregulated host response to infection. This dysregulated host response includes enhanced inflammatory responses and suppressed adaptive immunity, but the molecular mechanisms behind it have not yet been elucidated. CD72, a type II transmembrane protein that is primarily expressed in B cells, was found to play an immunomodulatory role in the immune system and was associated with mortality in patients with sepsis. However, whether CD72 affects the pathogenesis of sepsis by influencing the immune response remains unclear.

METHODS

We first collected peripheral blood from 40 healthy volunteers and 57 septic patients and analyzed the mRNA levels of CD72 and the expression of its soluble form sCD72 using Realtime-PCR and ELISA. We then employed the CRISPR/Cas9 system to generate CD72 knockout mice (CD72-KO) and established a cecal ligation and puncture (CLP) model to analyze the effects of CD72 gene deletion on the survival, organ injury and immune response of septic mice by Kaplan-Meier survival analysis, pathological sections and flow cytometry. We also observe the effects of excess sCD72 on survival and immune response in sepsis by injecting recombinant CD72 protein into mice. Finally, the mechanism of sCD72 affecting sepsis immunity was analyzed by fluorescence staining, confocal microscopy and flow cytometry.

RESULTS

We found that when sepsis occurs, the levels of CD72 mRNA and cell surface CD72 in immune cells decrease, while the level of soluble sCD72 in the blood increases significantly. Excessive sCD72 increased sepsis mortality in a dose-dependent manner, which can bind to CD100 on the surface of T cells and enter the cytoplasm, leading to impaired T cell functions, including a decrease in CD4+IFN-γ+, CD8+Perforin+, CD8+GZMB+, and CD8+FASL+ population and an increase in inflammatory CD4+TNF-α+ population, thereby suppressing adaptive immunity while enhancing inflammatory response.

CONCLUSION

The immunosuppression of sepsis has been recognized, but the underlying mechanism has not been fully elucidated. Our study identified for the first time that sCD72 is an important mediator that cause adaptive immunosuppression during sepsis, which leads to T cell suppression by competitively binding to CD100 on the surface of T cells. Our study provides novel insights in our understanding of sepsis-related immunosuppression and may provide translational opportunities for the design of new diagnostic biomarkers and therapeutic targets for sepsis.

Innovative nanoparticle-based approaches for modulating neutrophil extracellular traps in diseases: from mechanisms to therapeutics

Neutrophil extracellular traps (NETs) participate in both host defense and the pathogenesis of various diseases, such as infections, thrombosis, and tumors. While they help capture and eliminate pathogens, NETs' excessive or dysregulated formation can lead to tissue damage and disease progression. Therapeutic strategies targeting NET modulation have shown potential, but challenges remain, particularly in achieving precise drug delivery and maintaining drug stability. Nanoparticle (NP)-based drug delivery systems offer innovative solutions for overcoming the limitations of conventional therapies. This review explores the biological mechanisms of NET formation, their interactions with NPs, and the therapeutic applications of NP-based drug delivery systems for modulating NETs. We discuss how NPs can be designed to either promote or inhibit NET formation and provide a comprehensive analysis of their potential in treating NET-related diseases. Additionally, we address the current challenges and future prospects for NP-based therapies in NET research, aiming to bridge the gap between nanotechnology and NET modulation for the development of novel therapeutic approaches.

Sepsis subphenotypes: bridging the gaps in sepsis treatment strategies

Sepsis, a heterogeneous illness produced by a dysregulated host response to infection, remains a severe mortality risk. Recent discoveries in sepsis research have stressed phenotyping as a feasible strategy for tackling heterogeneity and enhancing therapy precision. Sepsis phenotyping has moved from traditional stratifications based on severity and prognosis to dynamic, phenotype-driven therapeutic options. This review covers recent progress in connecting sepsis subgroups to personalized treatments, with a focus on phenotype-based therapeutic predictions and decision-support systems. Despite ongoing challenges, such as standardizing phenotyping frameworks and incorporating findings into clinical practice, this topic has enormous promise. By investigating phenotypic variation in therapy responses, we hope to uncover new biomarkers and phenotype-driven therapeutic solutions, laying the groundwork for more effective therapies and, ultimately improving patient outcomes.

Gut microbes of the cecum versus the colon drive more severe lethality and multi-organ damage

Intestinal perforations lead to a high risk of sepsis-associated morbidity and multi-organ dysfunctions. A perforation allows intestinal contents (IC) to enter the peritoneal cavity, causing abdominal infections. Right- and left-sided perforations have different prognoses in humans, but the mechanisms associated with different cecum and colon perforations remain unclear. This study investigates how gut flora influences outcomes from perforations at different sites in mice. Using fecal-induced peritonitis mouse model, isolated IC from the cecum or colon was injected peritoneally at 2 mg/kg. Bacterial burden was quantified with quantitative PCR, and microbial communities were analyzed using 16S rRNA gene sequencing. Survival rates were monitored, and blood biochemical indices, histological changes, cytokines expression, immunological signaling and multiple-organ damage were assessed at 16 h post-injections. The results showed cecum IC developed more severe sepsis than colon IC, with shorter median survival time and greater multi-organ damage. Mice treated with cecum IC displayed elevated tissue damage markers in the liver, heart, and kidneys, contributing to worsened pathology. This was likely driven by systematic inflammatory cytokines production and lung inflammation. Mechanistically, cecum IC triggered stronger cGAS-STING and TBK1-NF-κB signaling, promoting systemic inflammation compared to the colon IC. Moreover, bacterial analysis demonstrated that cecum IC carry a higher bacterial burden than colon IC and exhibit a different microbial community. A detailed microbiome comparison revealed an increased abundance of potentially pathogenic bacteria in the cecum IC. These findings suggest that the site of intestinal perforation influences sepsis severity, with the cecum being associated with a higher bacterial burden and a relatively increased abundance of potentially pathogenic bacteria compared to the colon. Our findings first compared the lethality associated with the microbial composition of the cecum and colon, indicating the perforation site could help providers predict the severity of sepsis, thereby introducing a novel perspective to microbiology and sepsis research.

Transcriptomic analysis of key genes and signaling pathways in sepsis-associated intestinal mucosal barrier damage

OBJECTIVES

The aim is to analyze differentially expressed genes (DEGs) in mice with sepsis-related intestinal mucosal barrier damage and to explore the diagnostic and protective mechanisms of this condition at the transcriptome level.

METHODS

Small intestinal tissues from healthy male C57BL/6J mice subjected to Cecal ligation and puncture (CLP) and sham operation were collected. High-throughput sequencing was performed using the paired-end sequencing mode of the Illumina HiSeq platform. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted on the differentially expressed genes (DEGs). A protein-protein interaction (PPI) network was constructed using the STRING database, and hub genes were identified with Cytoscape. These hub genes were then validated using quantitative real-time polymerase chain reaction (RT-qPCR).

RESULTS

A total of 239 DEGs were identified, with 49 upregulated and 130 downregulated genes. KEGG enrichment analysis showed that these DEGs were primarily involved in cytokine-cytokine receptor interaction, Th1 and Th2 cell differentiation, viral protein interactions with cytokines and their receptors, and the IL-17 signaling pathway. The top 10 hub genes were selected using the cytoHubba plugin. Experimental validation confirmed that the expression levels of TBX21, CSF3, IL-6, CXCR3, and CXCL9 matched the sequencing results.

CONCLUSION

TBX21, CSF3, IL-6,CXCR3, and CXCL9 may be potential biological markers for the diagnosis and treatment the sepsis-associated intestinal mucosal barrier.

The Mechanisms of Sepsis Induced Coagulation Dysfunction and Its Treatment

Sepsis is a critical condition characterized by organ dysfunction due to a dysregulated response to infection that poses significant global health challenges. Coagulation dysfunction is nearly ubiquitous among sepsis patients. Its mechanisms involve platelet activation, coagulation cascade activation, inflammatory reaction imbalances, immune dysregulation, mitochondrial damage, neuroendocrine network disruptions, and endoplasmic reticulum (ER) stress. These factors not only interact but also exacerbate one another, leading to severe organ dysfunction. This review illustrates the mechanisms of sepsis-induced coagulopathy, with a focus on tissue factor activation, endothelial glycocalyx damage, and the release of neutrophil extracellular traps (NETs), all of which are potential targets for therapeutic interventions.

Itaconate drives pro-inflammatory responses through proteasomal degradation of GLO1

Itaconate is a small-molecule metabolite generated by the enzyme aconitate decarboxylase 1 (ACOD1), which is upregulated during inflammation. Traditionally, itaconate has been recognized for its anti-inflammatory properties; however, this study reveals a pro-inflammatory mechanism of itaconate in macrophages. We demonstrate that itaconate promotes the proteasomal degradation of glyoxalase 1 (GLO1) via Cys139. GLO1 is crucial for detoxifying methylglyoxal (MGO), a glycolysis byproduct that leads to advanced glycation end-products (AGEs). Elevated concentrations of itaconate correlate with reduced GLO1 expression in peripheral blood mononuclear cells (PBMCs) from patients with sepsis, linking increased itaconate concentrations to heightened MGO and AGE production. Functionally, itaconate-induced degradation of GLO1 promotes the accumulation of MGO and AGEs, thereby exacerbating inflammatory responses. In vivo, itaconate-treated myeloid-specific Ager conditional knockout mice exhibited reduced inflammation and improved survival in experimental sepsis models compared to wild-type controls. Collectively, these findings reveal a novel function of itaconate in immunometabolism, shedding light on its complex involvement in lethal infections.

Targeting protein kinase C-α prolongs survival and restores liver function in sepsis: Evidence from preclinical models

Sepsis is a life-threatening organ failure resulting from a poorly regulated infection response. Organ dysfunction includes hepatic involvement, weakening the immune system due to excretory liver failure, and metabolic dysfunction, increasing the death risk. Although experimental studies correlated excretory liver functionality with immune performance and survival rates in sepsis, the proteins and pathways involved remain unclear. This study identified protein kinase C-α (PKCα) as a novel target for managing excretory liver function during sepsis. Using a preclinical murine sepsis model, we found that both PKCα knockout and the use of a PKCα-inhibitor midostaurin successfully restored liver function without hindering the host's response or ability to clear the pathogen, highlighting PKCα's vital role in excretory liver failure. In septic animals, both approaches significantly boosted survival rates. Midostaurin is the clinically approved active pharmaceutical ingredient in Rydapt, approved for the adjuvant treatment of FTL3-mutated AML. Here, it reduced plasma bile acids and related inflammation in those patients, opening a translational avenue for therapeutics in sepsis. Conclusively, our research underscores the significance of PKCα in controlling excretory liver function during inflammation. This suggests that targeting this protein could restore liver function without compromising the immune system, thereby decreasing sepsis mortality and supporting the recent paradigm that the liver is a hub for the host response to infection that might, in the future, result in novel host-directed therapies supporting the current state-of-the-art intensive care medicine in patients with sepsis-associated liver failure.

The impact of diabetes on Sepsis-induced cardiomyopathy

PURPOSE

This study investigated the association between diabetes and Sepsis-induced cardiomyopathy (SIC), focusing on how changes in inflammatory response and cardiac function influence SIC prognosis. The aim is to provide clinicians with more accurate treatment and management strategies, ultimately enhancing patient outcomes and quality of life.

METHODS

This retrospective cohort study analyzed 258 Sepsis-induced cardiomyopathy (SIC) patients, stratified by diabetes status and HbA1C levels. Data were collected from electronic medical records. Statistical tests included the Kolmogorov-Smirnov, t-test, Mann-Whitney U, Kruskal-Wallis, chi-square, and Spearman correlation. Univariate and multivariate logistic regression assessed diabetes' impact on SIC severity. Model fit was evaluated with the Hosmer-Lemeshow and negative log-likelihood ratio tests. A nomogram was constructed and validated using ROC curves, calibration curves, and decision curve analysis. Subgroup and interaction analyses were performed (P < 0.05).

RESULTS

Diabetes worsened inflammation and immune responses in SIC, significantly affecting markers like LVEF, TnI, CK-MB, BNP, NLR, IL-6, PCT, CRP, APACHE II, and SOFA scores (P < 0.05). Grouping by HbA1C levels revealed no significant differences in LVEF (P = 0.078), Alb (P = 0.105), or L/A (P = 0.211), but differences were found for TnI, CK-MB, BNP, NLR, IL-6, PCT, CRP, APACHE II, and SOFA (P < 0.05). HbA1C strongly correlated with CRP (rs = 0.8664). BNP (OR 1.001) and HbA1C (OR 1.302) were significant risk factors for SIC, with the nomogram showing good predictive performance (AUC 0.693). No significant interaction between HbA1C and BNP on SIC severity was observed (P = 0.791).

CONCLUSION

Diabetes exacerbates inflammatory and immune responses in Sepsis-induced cardiomyopathy patients, leading to worsened cardiac function.

Optical Bionanosensors for Sepsis Diagnostics

Sepsis is a global health challenge, characterized by a dysregulated immune response, leading to organ dysfunction and death. Despite advances in medical care, sepsis continues to claim a significant toll on human lives, with mortality rates from 10-25% for sepsis and 30-50% for septic shock, making it a leading cause of death worldwide. Current diagnostic methods rely on clinical signs, laboratory parameters, or microbial cultures and suffer from delays and inaccuracies. Therefore, there is a pressing need for novel diagnostic tools that can rapidly and accurately identify sepsis. This review highlights advances in biosensor development that could ultimately lead to faster and more accurate sepsis diagnostics. The focus is on nanomaterial-based optical approaches that promise rapid diagnostics without the need for large equipment or trained personnel. An overview of sepsis is provided, highlighting potential molecular targets and the challenges they present for assay development. The requirements for an ideal point-of-care test (POC) are discussed, including speed, simplicity, and cost-effectiveness. Different nanomaterials suitable for various optical detection methods are reviewed and innovative nanosensors are discussed for sepsis diagnostics, focusing on chemical design and approaches to increase selectivity by multiplexing.

Hospital readmission after surviving sepsis: A systematic review of readmission reasons and meta-analysis of readmission rates

PURPOSE

To review the evidence regarding hospital readmission diagnoses and analyse related readmission rates following a sepsis admission.

METHODS

Five databases, grey literature, and selected article reference lists were searched in May and June 2024. Included studies investigated sepsis survivor readmissions and reported readmission diagnoses and rates. Meta-analyses of readmission rates were performed.

RESULTS

After screening, 51 studies were included, with most studies (46/51; 90.2 %) investigating adult survivors. Infection or sepsis were reported as the most common readmission reason in 18 of the 21 studies investigating three or more readmission diagnoses in adults. Meta-analyses showed that 4.7 % (95 % CI: 3.1 to 6.5 %, PI: 0.3-13.4 %, n = 11 studies) of adult survivors readmitted to hospital with another sepsis diagnosis at 30 days, 8.1 % (95 % CI: 4.5 to 12.7 %, PI: <0.1-29.0 %, n = 7) at 90 days, and 16.4 % (95 % CI: 11.3 to 22.2 %, PI: <0.1-96.3 %, n = 3) at one year. At 30 days 3.5 % (95 % CI: 2.2-5.0 %, PI: 0.3-10.0 %, n = 7) of adult survivors readmitted to hospital with a cardiovascular disease diagnosis.

CONCLUSIONS

Infection and sepsis are frequent readmission diagnoses for sepsis survivors, with one in 21 adult survivors readmitted for sepsis at 30-days. PROSPERO registration: CRD42023455851.

Resolvin D2 restores monocyte anisocytosis and mediates a shift toward classical monocytes ex vivo in blood samples from patients after major burns

Circulating monocytes contribute to the defense against pathogens and play a crucial role in maintaining immune homeostasis. While there is substantial evidence regarding the triggers of monocyte activation, our understanding of how monocyte function is restored toward homeostasis after activation remains limited. Here, we assessed the changes in monocyte anisocytosis upon activation in blood, measured by monocyte distribution width (MDW), a biomarker for sepsis. We determined that the increase in MDW post-lipopolysaccharide (LPS) stimulation in the blood can be reversed promptly by adding resolvin D2 (RvD2), and we measured a decrease in interleukin-1 beta (IL-1β) in blood, and a decrease in the size of the population of intermediate monocyte subsets. Moreover, the ex vivo addition of RvD2 to blood samples from burn patients with high MDW restored normal MDW values. Further studies are needed to probe the potential therapeutic role of RvD2 in the context of burn injuries.

Identification of DNA damage repair-related genes in sepsis using bioinformatics and machine learning: An observational study

Sepsis is a life-threatening disease with a high mortality rate, for which the pathogenetic mechanism still unclear. DNA damage repair (DDR) is essential for maintaining genome integrity. This study aimed to explore the role of DDR-related genes in the development of sepsis and further investigated their molecular subtypes to enrich potential diagnostic biomarkers. Two Gene Expression Omnibus datasets (GSE65682 and GSE95233) were implemented to investigate the underlying role of DDR-related genes in sepsis. Three machine learning algorithms were utilized to identify the optimal feature genes. The diagnostic value of the selected genes was evaluated using the receiver operating characteristic curves. A nomogram was built to assess the diagnostic ability of the selected genes via "rms" package. Consensus clustering was subsequently performed to identify the molecular subtypes for sepsis. Furthermore, CIBERSORT was used to evaluate the immune cell infiltration of samples. Three different expressed DDR-related genes (GADD45A, HMGB2, and RPS27L) were identified as sepsis biomarkers. Receiver operating characteristic curves revealed that all 3 genes showed good diagnostic value. The nomogram including these 3 genes also exhibited good diagnostic efficiency. A notable difference in the immune microenvironment landscape was discovered between sepsis patients and healthy controls. Furthermore, all 3 genes were significantly associated with various immune cells. Our findings identify potential new diagnostic markers for sepsis that shed light on novel pathogenetic mechanism of sepsis and, therefore, may offer opportunities for potential intervention and treatment strategies.

Anti-sepsis effects of Dahuang Mudan decoction and its disassembled prescriptions

ETHNOPHARMACOLOGICAL RELEVANCE

Dahuang Mudan decoction (DMD) is a traditional Chinese prescription from Zhang Zhongjing's Synopsis of the Golden Chamber. In clinical practice, it is often used in the treatment of infectious diseases.

AIM OF THE STUDY

To assess the therapeutic effect of DMD and its disassembled prescriptions on septic mice, and explore its potential mechanism.

MATERIALS AND METHODS

Cecal ligation and puncture (CLP) sepsis and endotoxemia mice models were established. The effects of DMD, its disassembled prescriptions and active compounds were studied. Xuebijing injection (XBJ) was used as positive drug. Mice 7-day survival rates, blood biochemical markers, hematoxylin and eosin (HE) staining and immune cell infiltration were used to evaluate the overall protective effect of the drugs on mice. Inflammatory cytokines and coagulation activation indicators were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

DMD, its Huoxue prescription, constituent drugs Mudanpi (MDP) and Taoren (TR) significantly protected mice with sepsis, improved the survival rate, reduced the degree of organ damage, and reduced the infiltration of immune cells in the lung tissues. The protective effect is comparable to that of XBJ. MDP and TR inhibited the levels of inflammatory factors and coagulation activation in septic mice. Paeonol and paeoniflorin in MDP showed significant protective effects on septic mice, and inhibited inflammatory cytokines level and coagulation activation.

CONCLUSION

These results confirm that DMD and its disassembled prescriptions have good therapeutic effect on septic mice, and the mechanism may be related to inhibition of the inflammatory response and coagulation activation.

Immunomodulatory effects and multi-omics analysis of Codonopsis Pilosula Extract in septic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Codonopsis Pilosula (CP), as a well-known traditional Chinese medicine (TCM) with medicinal and edible herb, is one of the most representative tonic Chinese herbal medicine. It has been widely used for regulating immune function with hardly any adverse effects in clinical practice.

AIM OF THE STUDY

This study aimed to elucidate the immunomodulatory effect and to explore probable mechanism of Codonopsis Pilosula Extract (CPE) in septic rats.

MATERIALS AND METHODS

The model of septic rat was established by cecal ligation and perforation (CLP). The thymus index, spleen index and cerebral index were calculated. Histological changes were observed by Hematoxylin-eosin (HE). The positive expression of CD4+ T cells was determined in the thymus and spleen by immunohistochemical (IHC). The expression level of 24 h CD4 was corroborated by real-time quantitative polymerase chain reaction (RT-QPCR). Infectious factors, immune factors and inflammatory factors were determined by enzyme-linked immunosorbent assay (ELISA). Blood cells were detected by automatic biochemical analyzer. The metabolite changes and gene expression levels, the potential targets and pathways of CPE in regulating immune function of thymus were analyzed by integrative analysis of transcriptomic and metabolomic methods.

RESULTS

High dose of CPE increased the thymus index and spleen index of septic rats at different stages, and the brain index at different stages could be increased at medium dose and high dose. Medium and high doses of CPE reduced the pathological changes of thymus, spleen and brain tissue. CPE promoted the expression levels of CD4 in the thymus and spleen. CPE improved the levels of red blood cells (RBC), lymphocytes (LYM) and hemoglobin (HGB), and decreased the levels of neutrophils (NEUT), NLR (NEUT/LYM) and PLR (PLT/LYM). CPE dynamically regulated the levels of white blood cells (WBC) and PLT (platelet). CPE dynamically regulated the expression levels of infectious factors, immune factors, and inflammatory factors related to disease severity.

CONCLUSION

CPE has the ability to dynamically modulate the expression levels of infectious factors, immune factors, and inflammatory factors related to disease severity, and alleviate the damages of immune organs. The research has provided a global view of the integration of metabolomics and transcriptomics to elucidate the immunomodulatory effects and mechanisms of CPE. CPE could affect a series of biological processes in glycerophospholipid metabolism by interfering with the B cell receptor (BCR) signaling pathway in the thymus, to maintain immune homeostasis of septic rats on the whole, especially humoral immunity.

Fermented Houttuynia cordata Juice Exerts Cardioprotective Effects by Alleviating Cardiac Inflammation and Apoptosis in Rats with Lipopolysaccharide-Induced Sepsis

BACKGROUND/OBJECTIVES

Sepsis-induced cardiac dysfunction is a major problem that often leads to severe complications and a poor prognosis. Despite the growing awareness of its impact, effective treatment options for sepsis-induced cardiac dysfunction remain limited. To date, fermented products of Houttuynia cordata (HC), known for its rich bioactive properties, have shown potential in modulating inflammatory and oxidative stress pathways. However, treatment with fermented HC juice (FHJ) in lipopolysaccharide (LPS)-induced sepsis in rats has not been investigated.

METHODS

Rats were pretreated with FHJ at doses of 200 mg/kg and 400 mg/kg for 2 weeks. After that, the rats were injected with a single dose of LPS (10 mg/kg), and 12 h after injection, they developed sepsis-induced cardiac dysfunction. Then, cardiac function, oxidative stress, inflammation, apoptosis, and cardiac injury markers were determined.

RESULTS

Pretreatment with FHJ at doses of 200 mg/kg and 400 mg/kg prevented LPS-induced cardiac dysfunction in rats by attenuating cardiac inflammation (IL-1β, TLR-4, and NF-κB levels), oxidative stress (MDA levels), and apoptosis (cleaved-caspase 3 and Bax/Bcl-2 expression) and reducing markers of cardiac injury (LDH and CK-MB levels).

CONCLUSIONS

These results suggest that FHJ could be a potential therapeutic agent for sepsis-induced heart disease.