Anisomycin protects against sepsis by attenuating IκB kinase-dependent NF-κB activation and inflammatory gene expression

Anti-Inflammatory Effects of Idebenone Attenuate LPS-Induced Systemic Inflammatory Diseases by Suppressing NF-κB Activation

Inflammation is a natural protective process through which the immune system responds to injury, infection, or irritation. However, hyperinflammation or long-term inflammatory responses can cause various inflammatory diseases. Although idebenone was initially developed for the treatment of cognitive impairment and dementia, it is currently used to treat various diseases. However, its anti-inflammatory effects and regulatory functions in inflammatory diseases are yet to be elucidated. Therefore, this study aimed to investigate the anti-inflammatory effects of idebenone in cecal ligation puncture-induced sepsis and lipopolysaccharide-induced systemic inflammation. Murine models of cecal ligation puncture-induced sepsis and lipopolysaccharide-induced systemic inflammation were generated, followed by treatment with various concentrations of idebenone. Additionally, lipopolysaccharide-stimulated macrophages were treated with idebenone to elucidate its anti-inflammatory effects at the cellular level. Idebenone treatment significantly improved survival rate, protected against tissue damage, and decreased the expression of inflammatory enzymes and cytokines in mice models of sepsis and systemic inflammation. Additionally, idebenone treatment suppressed inflammatory responses in macrophages, inhibited the NF-κB signaling pathway, reduced reactive oxygen species and lipid peroxidation, and normalized the activities of antioxidant enzyme. Idebenone possesses potential therapeutic application as a novel anti-inflammatory agent in systemic inflammatory diseases and sepsis.

MCC950 improves lipopolysaccharide‑induced systemic inflammation in mice by relieving pyroptosis in blood neutrophils

Sepsis is an infection-induced systemic inflammatory response syndrome accompanied by multiple organ injury and failure. MCC950, an inhibitor of NLR family pyrin domain containing 3 (NLRP3), can alleviate the inflammatory response and relieve inflammation-induced injury. The aim of the present study was to explore the efficacy of MCC950 in lipopolysaccharide (LPS)-induced inflammation and elucidate the underlying mechanisms. Based on a prior study, C57BL/6 mice were divided into three groups: Control, LPS, and LPS + MCC950. The mice were administered 10 mg/kg LPS to induce sepsis and 10 mg/kg MCC950 to treat sepsis 6 h before and after LPS injection. Histopathological imaging revealed organ morphology and damage during inflammation, and MCC950 alleviated organ damage and dysfunction. MCC950 prevented LPS-induced inflammatory responses by reducing inflammatory cytokine levels in the blood. To explore the mechanism by which MCC950 functions, blood neutrophils were isolated and a series of tests were performed. As revealed by measuring reactive oxygen species levels and Annexin V/PI staining of neutrophils, MCC950 reduced oxidative stress and programmed death induced by LPS. Western blotting was used to assess the protein levels of pyroptosis-related markers, including GSDMD, NLRP3, and caspase-1, in neutrophils to further explore the form of death. MCC950 reduced LPS-induced pyroptosis in neutrophils. The results of the survival analysis revealed that MCC950 increased the survival rates of mice within 72 h of LPS injection. MCC950 may be an effective treatment for sepsis that targets neutrophil pyroptosis.

IL2RB affects Th1/Th2 and Th17 responses of peripheral blood mononuclear cells from septic patients

BACKGROUND

Immune dysfunction is a common and serious complication of sepsis. This study finds key genes linked to immunity in sepsis.

METHODS

The "Limma package" was used to analyze GSE154918 datasets for differentially expressed genes. The differentially expressed genes were then enriched for Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and interleukin 2 receptor subunit Beta (IL2RB) protein coding gene was chosen for investigation. IL2RB expression in peripheral blood mononuclear cells (PBMC) was assessed by polymerase chain reaction. White blood cells of septic patients and healthy controls were collected from hospitals and linked with acute physiology and chronic health evaluation (APACHE) II, sequential organ failure assessment (SOFA), C-reactive protein (CRP), and procalcitonin (PCT) of septic patients using Pearson's correlation analysis. PBMC cells were transfected with IL2RB, and the effect of transfection was observed on cellular interferon gamma (IFN-γ), interleukin (IL)-12, IL-4, IL-10, and IL-17A.

RESULTS

A total of 686 differential genes, comprising 446 upregulated and 240 down regulated genes, were identified. The enrichment of KEGG pathway revealed that the majority of differential genes were enriched in the T helper (Th1)/Th2 cell and Th17 cell differentiation pathways. In patients with sepsis, correlation analysis revealed a negative correlation between IL2RB and APACHE II score, SOFA score, CRP, and PCT. IFN-γ and IL-12 levels were elevated in PBMC of septic patients after IL2RB transfection, but IL-4, IL-10, and IL-17A levels were lowered.

CONCLUSION

Sepsis-induced immunological dysfunction is improved by IL2RB, which also balances Th1/Th2 responses and prevents Th17 activation. © 2023 Codon Publications. Published by Codon Publications.

NOD2 is involved in regulating odontogenic differentiation of DPSCs suppressed by MDP through NF-κB/p65 signaling

Dental pulp stem cells (DPSCs) are well known for their capable of both self-renewal and multilineage differentiation. Dental tissue diseases, include caries, are often accompanied by inflammatory microenvironment, and muramyl dipeptide (MDP) is involved in the inflammatory stimuli to influence the differentiation of DPSCs. Nucleotide-binding oligomerization domain 2 (NOD2), a member of the cytosolic Nod-like receptor (NLR) family, plays a key role in inflammatory homeostasis regulation, but the role of NOD2 in DPSCs differentiation under inflammatory is still unclear. In this study, we identified that MDP suppressed odontogenic differentiation of DPSCs via NOD2/ NF-κB/p65 signaling pathway. Alizarin red staining and ALP activity showed the odontogenic differentiation was suppressed by MDP in a concentration-dependent manner, and the expression of dentin differentiation marker protein dentin matrix protein 1 (DMP-1) and dentin Sialophosphoprotein (DSPP) also indicated the same results. The expression of NOD2 increased gradually with the concentration of MDP as well as the phosphorylation and nuclear translocation of p65, which meant NF-κB signaling pathway was activated. Further, the interference of NOD2 inhibited the phosphorylation and nuclear translocation of p65 and reversed the MDP-mediated decrease of odontoblast differentiation of DPSCs. Our study showed that MDP can inhibit the odontoblast differentiation of DPSCs in a concentration-dependent manner. The NF-κB signaling pathway was activated by increasing expression of NOD2. Interference of NOD2 reversed the negative ability odontoblast differentiation of DPSCs in the inflammatory environment. Our study might provide a theoretical basis for the clinical treatment for dentinogenesis of DPSCs.

MAGP2 induces tumor progression by enhancing uPAR-mediated cell proliferation

Microfibril-associated glycoprotein 2 (MAGP2) plays an important role in regulating cell signaling and acts as a biomarker to predict the prognostic effect of tumor therapy. However, research on MAGP2 mostly focuses on its extracellular signal transmission features, and its potential intracellular function is rarely reported. Here, we reported that intracellular MAGP2 increased the stability of urokinase-type plasminogen activator receptor (uPAR) in the cell by direct interaction which inhibits the lysosomal-mediated degradation of uPAR. Furthermore, with the detection of protein content changes and proteomics analysis, we found that highly expressed MAGP2 promoted the proliferation of tumor cells through uPAR-mediated p38-NF-ĸB signaling axis activation, enhancement of DNA damage repair and reduction of cell stagnation in the S phase of the cell cycle. In the nude mouse xenograft model of colorectal cancer, the upregulation of MAGP2 in tumor cells significantly promoted tumor progression, while the downregulation of uPAR significantly attenuated tumor progression. These studies elucidate the role of MAGP2 inside the cell and provide a new explanation for why patients with higher MAGP2 expression in tumors are associated with a worse prognosis. In addition, we also determined a mechanism for the stable existence of uPAR in the cell, providing information for the development of tumor drugs targeting uPAR.