Current insight on the mechanisms of programmed cell death in sepsis-induced myocardial dysfunction

Ozone controls the metabolism of tryptophan protecting against sepsis-induced intestinal damage by activating aryl hydrocarbon receptor

BACKGROUND

Intestinal injury is the most common complication of sepsis, and the mitigation of intestinal damage is crucial for treating sepsis.

AIM

To examine the use of ozone-rich water and its action in preventing intestinal damage caused by sepsis.

METHODS

Through histological analysis, immunohistochemistry, immunofluorescence assays, and Western blot detection, we evaluated the therapeutic efficacy of ozone in mitigating intestinal injury during sepsis. Additionally, by conducting 16S rRNA sequencing and untargeted metabolomics analysis on fecal samples, we identified alterations in the gut microbiota and specific metabolites in septic mice following ozone treatment. This comprehensive approach aims to further elucidate the mechanistic underpinnings of ozone therapy in alleviating sepsis-induced intestinal damage.

RESULTS

Our results demonstrate that ozonated water significantly ameliorates pathological damage in intestinal tissues, enhances the expression of tight junction proteins, and inhibits the polarization of intestinal macrophages, thereby reducing the expression of inflammatory cytokines in intestinal tissues of cecal ligation and puncture-induced septic mice. 16S rRNA sequencing analysis revealed that ozonated water increased the abundance of beneficial bacteria and alleviated gut microbiota dysbiosis. Studies using broad-spectrum antibiotic-treated mice indicated that the protective effects of ozonated water on intestinal injury are dependent on the gut microbiota. Furthermore, metabolomic analysis identified an increase in the tryptophan metabolite DL-tryptophan in the ozonated water treatment group. This suggests that ozonated water protects against intestinal injury by activating the aryl hydrocarbon receptor and suppressing necroptosis in intestinal epithelial cells.

CONCLUSION

Ozone protected against sepsis-induced intestinal injury through regulation of the gut microbiota and tryptophan metabolism, inhibiting necrotic apoptosis of intestinal epithelial cells through activation of the aryl hydrocarbon receptor.

Advances in neutrophil extracellular traps and ferroptosis in sepsis-induced cardiomyopathy

Sepsis-induced cardiomyopathy is a reversible non-ischemic acute cardiac dysfunction associated with sepsis. It is strongly associated with an abnormal immune response. It emerges as a vital threat to public health owing to its high mortality rate. However, the exact pathogenesis requires further investigation. In recent years, NETosis and ferroptosis, which are novel modes of programmed cell death, have been identified and found to play important roles in sepsis-related organ damage. This article outlines the mechanisms of these two modes of cell death, discusses the role of neutrophil extracellular traps in myocardial injury and the importance of ferroptosis in sepsis-induced cardiomyopathy, and reviews the potential interconnection between these two types of programmed cell death in sepsis-induced cardiomyopathy.

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.

Exosomes and non-coding RNAs: Exploring their roles in human myocardial dysfunction

Myocardial dysfunction, characterized by impaired cardiac muscle function, arises from diverse etiologies, including coronary artery disease, myocardial infarction, cardiomyopathies, hypertension, and valvular heart disease. Recent advancements have highlighted the roles of exosomes and non-coding RNAs in the pathophysiology of myocardial dysfunction. Exosomes are small extracellular vesicles released by cardiac and other cells that facilitate intercellular communication through their molecular cargo, including ncRNAs. ncRNAs are known to play critical roles in gene regulation through diverse mechanisms, impacting oxidative stress, fibrosis, and other factors associated with myocardial dysfunction. Dysregulation of these molecules correlates with disease progression, presenting opportunities for therapeutic interventions. This review explores the mechanistic interplay between exosomes and ncRNAs, underscoring their potential as biomarkers and therapeutic agents in myocardial dysfunction. Emerging evidence supports the use of engineered exosomes and modified ncRNAs to enhance cardiac repair by targeting signaling pathways associated with fibrosis, apoptosis, and angiogenesis. Despite promising preclinical results, delivery, stability, and immunogenicity challenges remain. Further research is needed to optimize clinical translation. Understanding these intricate mechanisms may drive the development of innovative strategies for diagnosing and treating myocardial dysfunction, ultimately improving patient outcomes.

Forms of Non-Apoptotic Cell Death and Their Role in Gliomas-Presentation of the Current State of Knowledge

In addition to necrosis and apoptosis, the two forms of cell death that have been known for many decades, other non-apoptotic forms of cell death have been discovered, many of which also play a role in tumors. Starting with the description of autophagy more than 60 years ago, newer forms of cell death have become important for the biology of tumors, such as ferroptosis, pyroptosis, necroptosis, and paraptosis. In this review, all non-apoptotic and oncologically relevant forms of programmed cell death are presented, starting with their first descriptions, their molecular characteristics, and their role and their interactions in cell physiology and pathophysiology. Based on these descriptions, the current state of knowledge about their alterations and their role in gliomas will be presented. In addition, current efforts to therapeutically influence the molecular components of these forms of cell death will be discussed. Although research into their exact role in gliomas is still at a rather early stage, our review clarifies that all these non-apoptotic forms of cell death show significant alterations in gliomas and that important insight into understanding them has already been gained.

High-dose Vitamin C injection ameliorates against sepsis-induced myocardial injury by anti-apoptosis, anti-inflammatory and pro-autophagy through regulating MAPK, NF-κB and PI3K/AKT/mTOR signaling pathways in rats

AIMS

This study aimed to evaluate the effects of VC on SIMI in rats.

METHODS

In this study, the survival rate of high dose VC for SIMI was evaluated within 7 days. Rats were randomly assigned to three groups: Sham group, CLP group, and high dose VC (500 mg/kg i.v.) group. The animals in each group were treated with drugs for 1 day, 3 days or 5 days, respectively. Echocardiography, myocardial enzymes and HE were used to detect cardiac function. IL-1β, IL-6, IL-10 and TNF-α) in serum were measured using ELISA kits. Western blot was used to detect proteins related to apoptosis, inflammation, autophagy, MAPK, NF-κB and PI3K/Akt/mTOR signaling pathways.

RESULTS

High dose VC improved the survival rate of SIMI within 7 days. Echocardiography, HE staining and myocardial enzymes showed that high-dose VC relieved SIMI in rats in a time-dependent manner. And compared with CLP group, high-dose VC decreased the expressions of pro-apoptotic proteins, while increased the expression of anti-apoptotic protein. And compared with CLP group, high dose VC decreased phosphorylation levels of Erk1/2, P38, JNK, NF-κB and IKK α/β in SIMI rats. High dose VC increased the expression of the protein Beclin-1 and LC3-II/LC3-I ratio, whereas decreased the expression of P62 in SIMI rats. Finally, high dose VC attenuated phosphorylation of PI3K, AKT and mTOR compared with the CLP group.

SIGNIFICANCE

Our results showed that high dose VC has a good protective effect on SIMI after continuous treatment, which may be mediated by inhibiting apoptosis and inflammatory, and promoting autophagy through regulating MAPK, NF-κB and PI3K/AKT/mTOR pathway.