Up-regulation of DcR3 in microbial toxins-stimulated HUVECs involves NF-κB signalling

Research Progress of DcR3 in the Diagnosis and Treatment of Sepsis

Decoy receptor 3 (DcR3), a soluble glycosylated protein in the tumor necrosis factor receptor superfamily, plays a role in tumor and inflammatory diseases. Sepsis is a life-threatening organ dysfunction caused by the dysregulation of the response to infection. Currently, no specific drug that can alleviate or even cure sepsis in a comprehensive and multi-level manner has been found. DcR3 is closely related to sepsis and considerably upregulated in the serum of those patients, and its upregulation is positively correlated with the severity of sepsis and can be a potential biomarker for diagnosis. DcR3 alone or in combination with other markers has shown promising results in the early diagnosis of sepsis. Furthermore, DcR3 is a multipotent immunomodulator that can bind FasL, LIGHT, and TL1A through decoy action, and block downstream apoptosis and inflammatory signaling. It also regulates T-cell and macrophage differentiation and modulates immune status through non-decoy action; therefore, DcR3 could be a potential drug for the treatment of sepsis. The application of DcR3 in the treatment of a mouse model of sepsis also achieved good efficacy. Here, we introduce and discuss the progress in, and suggest novel ideas for, research regarding DcR3 in the diagnosis and treatment of sepsis.

The dual role of the CD95 and CD95L signaling pathway in glioblastoma

Binding of CD95, a cell surface death receptor, to its homologous ligand CD95L, transduces a cascade of downstream signals leading to apoptosis crucial for immune homeostasis and immune surveillance. Although CD95 and CD95L binding classically induces programmed cell death, most tumor cells show resistance to CD95L-induced apoptosis. In some cancers, such as glioblastoma, CD95-CD95L binding can exhibit paradoxical functions that promote tumor growth by inducing inflammation, regulating immune cell homeostasis, and/or promoting cell survival, proliferation, migration, and maintenance of the stemness of cancer cells. In this review, potential mechanisms such as the expression of apoptotic inhibitor proteins, decreased activity of downstream elements, production of nonapoptotic soluble CD95L, and non-apoptotic signals that replace apoptotic signals in cancer cells are summarized. CD95L is also expressed by other types of cells, such as endothelial cells, polymorphonuclear myeloid-derived suppressor cells, cancer-associated fibroblasts, and tumor-associated microglia, and macrophages, which are educated by the tumor microenvironment and can induce apoptosis of tumor-infiltrating lymphocytes, which recognize and kill cancer cells. The dual role of the CD95-CD95L system makes targeted therapy strategies against CD95 or CD95L in glioblastoma difficult and controversial. In this review, we also discuss the current status and perspective of clinical trials on glioblastoma based on the CD95-CD95L signaling pathway.

Gypenosides Inhibit Inflammatory Response and Apoptosis of Endothelial and Epithelial Cells in LPS-Induced ALI: A Study Based on Bioinformatic Analysis and in vivo/vitro Experiments

Introduction

Severe inflammatory response leads to poor prognosis of acute lung injury (ALI), the role of gypenosides (GPs) on ALI is not fully clear. The study aimed at investigating the effects of GPs on ALI.

Methods

We firstly established LPS-induced ALI mice model. Then, we tested whether GPs contributed to alleviate inflammatory response and lung injury of ALI in vivo. In order to identify specific mechanisms of the phenomenon, we conducted a bioinformatic analysis of LPS-induced ALI mice based on GEO database to identify hub differentially expressed genes (DEGs). PPI network of the DEGs was used to find hub-genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were conducted based on the DAVID database to identify which pathways the genes enriched. Then, we tested whether GPs inhibited lung injury and inflammatory response via the enriched pathways. We also tested whether GPs inhibited the apoptosis of endothelial and epithelial cells secondary to severe inflammation.

Results

We found GPs significantly alleviated lung injury and improved the survival rate of LPS-induced ALI mice in vivo. Bioinformatic analysis identified 20 hub-genes from DEGs, they were mainly enriched in NF-κB and TNF-α pathways. GPs could reduce the lung injury and inflammatory response via inhibiting NF-κB and TNF-α pathways in vivo. Our results indicated that GPs also inhibited inflammatory response of epithelial and endothelial cells via NF-κB and TNF-α pathways in vitro. Severe inflammatory response could also lead to apoptosis of endothelial and epithelial cells. Our results indicated that GPs effectively inhibited the apoptosis of endothelial and epithelial cells.

Conclusion

Our study suggested GPs contributed to alleviated lung injury in vivo and inhibited inflammation and apoptosis of endothelial and epithelial cells in vitro, providing novel strategies for the prevention and therapy for ALI.