uPA affects the CRSsNP nasal mucosa epithelium apoptosis by regulating WIF1

Quercetin Alleviates the Progression of Chronic Rhinosinusitis Without Nasal Polyps by Inhibiting Nasal Mucosal Inflammation and Epithelial Apoptosis

Chronic rhinosinusitis (CRS) is a common chronic inflammatory upper respiratory tract, has a major subtype of CRS without nasal polyps (CRSsNP), constituting a great global health problem. Quercetin exerts the important roles in several inflammatory diseases. However, its function in CRSsNP remains unclear. In this study, quercetin dose-dependently alleviated allergic nasal symptoms of increased frequencies of sneezing and nasal scratching in Staphylococcus aureus-constructed CRSsNP mice. Importantly, quercetin attenuated the histopathological changes of nasal mucosa tissue in model mice, including mucosal thickening, glandular hyperplasia, noticeable mast cells, and inflammatory cell infiltration. Concomitantly, quercetin alleviated the increased mucosal inflammation in CRSsNP mice by suppressing the transcripts and releases of pro-inflammatory IL-1β, IL-6, and IL-4. Notably, quercetin restrained X-box binding protein 1 (XBP1)-mediated activation of the HIF-1α/wnt-β-catenin axis in nasal mucosal tissues in CRSsNP model. Intriguingly, intranasal instillation of Lv-XBP1 offset the protective efficacy of quercetin against the progression of CRSsNP by suppressing the production of inflammatory cytokine IL-1β, IL-6, and IL-4, frequency of sneezing and nasal scratching, and histopathological changes of nasal mucosa tissues. In vitro, higher expression of XBP1 was observed in human nasal epithelial cells (HNECs) of CRSsNP relative to the normal HNECs. Moreover, elevation of XBP1 by Lv-XBP1 treatment suppressed cell proliferation and increased apoptosis of CRSsNP HNECs. Mechanistically, XBP1 overexpression increased the expression of HIF-1α and β-catenin, indicating the activation of the HIF-1α/wnt-β-catenin axis. Nevertheless, treatment with quercetin inhibited XBP1-induced cell apoptosis and reversed XBP1-mediated inhibition in cell proliferation in HNECs, as well as the activation of the HIF-1α/wnt-β-catenin axis. Thus, these findings reveal that quercetin may attenuate the progression of CRSsNP by inhibiting nasal mucosal inflammation and epithelial barrier dysfunction via blocking the XBP1/HIF-1α/wnt-β-catenin pathway, supporting a promising agent against CRSsNP.

Connecting impaired fibrinolysis and dyslipidemia

A State of the Art lecture entitled "Connecting Fibrinolysis and Dyslipidemia" was presented at the International Society on Thrombosis and Haemostasis Congress 2023. Hemostasis balances the consequences of blood clotting and bleeding. This balance relies on the proper formation of blood clots, as well as the breakdown of blood clots. The primary mechanism that breaks down blood clots is fibrinolysis, where the fibrin net becomes lysed and the blood clot dissolves. Dyslipidemia is a condition where blood lipid and lipoprotein levels are abnormal. Here, we review studies that observed connections between impaired fibrinolysis and dyslipidemia. We also summarize the different correlations between thrombosis and dyslipidemia in different racial and ethnic groups. Finally, we summarize relevant and new findings on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress. More studies are needed to investigate the mechanistic connections between impaired fibrinolysis and dyslipidemia and whether these mechanisms differ in racially and ethnically diverse populations.

Hypoxia-inducible factor 1α activates the NLRP3 inflammasome to regulate epithelial differentiation in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is an upper airway inflammation disease associated with hypoxia-mediated inflammation. The effect of hypoxia-inducible factor 1α (HIF-1α) on NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation in the pathogenesis of sinonasal mucosa is unclear.

OBJECTIVE

We investigated the effect and mechanism of HIF-1α on NLRP3 inflammasome activation in the primary human nasal epithelial cells (hNECs).

METHODS

We measured the expression levels of HIF-1α and the NLRP3 inflammasome in nasal biopsy samples and hNECs derived from negative controls (healthy) and patients with CRS with and without nasal polyps, then further analyzed the specific mechanism of HIF-1α regulation of the NLRP3 inflammasome and its effect on hNEC differentiation.

RESULTS

Increased mRNA and protein expression levels of HIF-1α and the NLRP3 inflammasome were found in all CRS biopsy samples. HIF-1α enhanced expression of phosphorylated NLRP3 (S295) in both HEK293T cells and hNECs; it also promoted recruitment of caspase-1 and apoptotic speck-like protein containing caspase recruitment domain (aka ASC) by NLRP3. HIF-1α also improved NLRP3's stability by preventing NLRP3 degradation caused by hypoxia-mediated inflammation. In addition, HIF-1α could also increase expression of Mucin5AC and decrease expression of α-tubulin by promoting activation of the NLRP3 inflammasome in hNECs. In addition, HIF-1α could also directly promote P63 expression in hNECs.

CONCLUSION

HIF-1α could potentially induce cilia loss and enhance the proliferation of goblet cells, possibly mediated by the regulation of NLRP3 phosphorylation in CRS inflammation.

Transcriptomic Differentiation of Phenotypes in Chronic Rhinosinusitis and Its Implications for Understanding the Underlying Mechanisms

Chronic rhinosinusitis (CRS) is a multifaceted disease with variable clinical courses and outcomes. We aimed to determine CRS-associated nasal-tissue transcriptome in clinically well-characterized and phenotyped individuals, to gain a novel insight into the biological pathways of the disease. RNA-sequencing of tissue samples of patients with CRS with polyps (CRSwNP), without polyps (CRSsNP), and controls were performed. Characterization of differently expressed genes (DEGs) and functional and pathway analysis was undertaken. We identified 782 common CRS-associated nasal-tissue DEGs, while 375 and 328 DEGs were CRSwNP- and CRSsNP-specific, respectively. Common key DEGs were found to be involved in dendritic cell maturation, the neuroinflammation pathway, and the inhibition of the matrix metalloproteinases. Distinct CRSwNP-specific DEGs were involved in NF-kβ canonical pathways, Toll-like receptor signaling, HIF1α regulation, and the Th2 pathway. CRSsNP involved the NFAT pathway and changes in the calcium pathway. Our findings offer new insights into the common and distinct molecular mechanisms underlying CRSwNP and CRSsNP, providing further understanding of the complex pathophysiology of the CRS, with future research directions for novel treatment strategies.

Transcriptome analysis reveals the protective role of fructo-oligosaccharide in colonic mucosal barriers in exercise-induced stressed mice

Most athletes continually endure mental and physical stress from intense exercise. Fructo-oligosaccharide (FOS) can reduce physical exhaustion, but the concrete mechanism behind it still needs further research. In this study, the effect of FOS on colonic mucosal barriers was investigated using an exercise-induced stress mouse model. Except for control individuals, mice were subject to cycles of 2-day exercise (at 20 rpm) interleaved by 5-day rest. The mice experienced a total of 6 days of exercise during the feeding period. FOS improved common indicators of exhaustion, such as glycogen storage in muscle. 16S rRNA data supported that changes in the gut microbiome were also closely related to stress status. Notably, Anaerotruncus was increased in mice under stress, while FOS facilitated the growth of Dorea, which is negatively associated with exhaustion. The RNA-seq analysis revealed that FOS could maintain the integrity of colonic epithelial barriers. For example, FOS significantly restored the expression of tight junctions (Occludin and Zonula occludens-1) in the colon, which was impaired under a stress state. Besides, the NOD-like receptor family pyrin domain containing 6 (NLRP6) inflammasome might contribute to the protection of the colonic mucosa by promoting the secretion of IL-18, Mucin2 (Muc2) and intestine lectin 1 (Itln1) in FOS-treated individuals. In short, FOS administration attenuated the damage of colonic mucosal barriers in exercise-induced stressed mice.

Identification of Key Modules, Hub Genes, and Noncoding RNAs in Chronic Rhinosinusitis with Nasal Polyps by Weighted Gene Coexpression Network Analysis

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease with relatively easy recurrence. However, the precise molecular mechanisms of this disease are poorly known. Based on gene sequencing data obtained from the Gene Expression Omnibus (GEO) database, we constructed coexpression networks by weighted gene coexpression network analysis (WGCNA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed by the Database for Annotation, Visualization, and Integrated Discovery (DAVID). The core gene of pathogenesis, CRSwNP, was screened by protein-protein interaction data (PPI) from the HPRD database. Unsupervised clustering was applied to screen hub genes related to the phenotype of CRSwNP. Blue and turquoise modules were found to be most significantly related to the pathogenicity of CRSwNP. Functional enrichment analysis showed that cell proliferation in the blue modules, the apoptotic process in the turquoise module, and the cancer pathway in both modules were mostly significantly correlated with the development of CRSwNP. The noncoding RNAs (long noncoding RNA and microRNA) and the top 10 core genes in each module were found to be associated with the pathogenesis of CRSwNP. A total of nine hub genes were identified to be related to the CRSwNP phenotype. By qRT-PCR analysis, AKT1, CDH1, PIK3R1, CBL, LRP1, MALAT1, and XIST were proven to be associated with the pathogenesis of CRSwNP. AGR2, FAM3D, PIP, DSE, and TMC were identified to be related to the CRSwNP phenotype. Further exploration of these genes will reveal more important information about the mechanisms of CRSwNP.