MicroRNA-29b regulates pyroptosis involving calcific aortic valve disease through the STAT3/SOCS1 pathway

Lentinus edodes mycelium polysaccharide inhibits AGEs-induced HUVECs pyroptosis by regulating LncRNA MALAT1/miR-199b/mTOR axis and NLRP3/Caspase-1/GSDMD pathway

A novel Lentinus edodes mycelia polysaccharide (LMP) prepared in our laboratory has been identified to be effective in inhibiting the damage of islet β cells induced by glucose toxicity. However, whether it can effectively alleviate the pyroptosis of human umbilical vein endothelial cells (HUVECs) induced by advanced glycation end products (AGEs) remains unclear. Bioinformatics and cell biology techniques were used to explore the mechanism of LMP inhibiting AGEs-induced HUVECs damage. The results indicated that AGEs significantly increased the expression of LncRNA MALAT1, decreased cell viability to 79.67 %, increased intracellular ROS level to 248.19 % compared with the control group, which further led to cell membrane rupture. The release of LDH in cellular supernatant was increased to 149.42 %, and the rate of propidium iodide staining positive cells increased to 277.19 %, indicating the cell pyroptosis occurred. However, the above trend was effectively retrieved after the treatment with LMP. LMP effectively decreased the expression of LncRNA MALAT1 and mTOR, promoted the expression of miR-199b, inhibited AGEs-induced HUVECs pyroptosis by regulating the NLRP3/Caspase-1/GSDMD pathway. LncRNA MALAT1 might be a new target for LMP to inhibit AGEs-induced HUVECs pyroptosis. This study manifested the role of LMP in improving diabetes angiopathy and broadens the application of polysaccharide.

The Impact of NLRP3 Inflammasome on Osteoblasts and Osteogenic Differentiation: A Literature Review

Osteoblasts (OBs), which are a crucial type of bone cells, derive from bone marrow mesenchymal stem cells (MSCs). Accumulating evidence suggests inflammatory cytokines can inhibit the differentiation and proliferation of OBs, as well as interfere with their ability to synthesize bone matrix, under inflammatory conditions. NLRP3 inflammasome is closely associated with cellular pyroptosis, which can lead to excessive release of pro-inflammatory cytokines, causing tissue damage and inflammatory responses, however, the comprehensive roles of NLRP3 inflammasome in OBs and their differentiation have not been fully elucidated, making targeting NLRP3 inflammasome approaches to treat diseases related to OBs uncertain. In this review, we provide a summary of NLRP3 inflammasome activation and its impact on OBs. We highlight the significant roles of NLRP3 inflammasome in regulating OBs differentiation and function. Furthermore, current available strategies to affect OBs function and osteogenic differentiation targeting NLRP3 inflammasome are listed and analyzed. Finally, through the prospective discussion, we seek to provide novel insights into the crucial role of NLRP3 inflammasome in diseases related to OBs and offer valuable information for devising treatment strategies.

Selenomethionine modulates the JAK2 / STAT3 / A20 pathway through oxidative stress to alleviate LPS-induced pyroptosis and inflammation in chicken hearts

Selenium (Se) is involved in many physiopathologic processes in humans and animals and is strongly associated with the development of heart disease. Lipopolysaccharides (LPS) are cell wall components of gram-negative bacteria that are present in large quantities during environmental pollution. To investigate the mechanism of LPS-induced cardiac injury and the efficacy of the therapeutic effect of SeMet on LPS, a chicken model supplemented with selenomethionine (SeMet) and/or LPS treatment, as well as a primary chicken embryo cardiomyocyte model with the combined effect of SeMet / JAK2 inhibitor (INCB018424) and/or LPS were established in this experiment. CCK8 kit, Trypan blue staining, DCFH-DA staining, oxidative stress kits, immunofluorescence staining, LDH kit, real-time fluorescence quantitative PCR, and western blot were used. The results proved that LPS exposure led to ROS explosion, hindered the antioxidant system, promoted the expression of the JAK2 pathway, and increased the expression of genes involved in the pyroptosis pathway, inflammatory factors, and heat shock proteins (HSPs). Upon co-treatment with SeMet and LPS, SeMet reduced LPS-induced pyroptosis and inflammation and restored the expression of HSPs by inhibiting the ROS burst and modulating the antioxidant capacity. Co-treatment with INCB018424 and LPS resulted in inhibited of the JAK2 pathway, attenuating pyroptosis, inflammation, and high expression of HSPs. Thus, LPS induced pyroptosis, inflammation, and changes in HSPs activity by activating of the JAK2 / STAT3 / A20 signaling axis in chicken hearts. Moreover, SeMet has a positive effect on LPS-induced injury. This work further provides a theoretical basis for treating cardiac injury by SeMet.

Identification of pyroptosis-associated genes with diagnostic value in calcific aortic valve disease

Background

Calcific aortic valve disease (CAVD) is one of the most prevalent valvular diseases and is the second most common cause for cardiac surgery. However, the mechanism of CAVD remains unclear. This study aimed to investigate the role of pyroptosis-related genes in CAVD by performing comprehensive bioinformatics analysis.

Methods

Three microarray datasets (GSE51472, GSE12644 and GSE83453) and one RNA sequencing dataset (GSE153555) were obtained from the Gene Expression Omnibus (GEO) database. Pyroptosis-related differentially expressed genes (DEGs) were identified between the calcified and the normal valve samples. LASSO regression and random forest (RF) machine learning analyses were performed to identify pyroptosis-related DEGs with diagnostic value. A diagnostic model was constructed with the diagnostic candidate pyroptosis-related DEGs. Receiver operating characteristic (ROC) curve analysis was performed to estimate the diagnostic performances of the diagnostic model and the individual diagnostic candidate genes in the training and validation cohorts. CIBERSORT analysis was performed to estimate the differences in the infiltration of the immune cell types. Pearson correlation analysis was used to investigate associations between the diagnostic biomarkers and the immune cell types. Immunohistochemistry was used to validate protein concentration.

Results

We identified 805 DEGs, including 319 down-regulated genes and 486 up-regulated genes. These DEGs were mainly enriched in pathways related to the inflammatory responses. Subsequently, we identified 17 pyroptosis-related DEGs by comparing the 805 DEGs with the 223 pyroptosis-related genes. LASSO regression and RF algorithm analyses identified three CAVD diagnostic candidate genes (TREM1, TNFRSF11B, and PGF), which were significantly upregulated in the CAVD tissue samples. A diagnostic model was constructed with these 3 diagnostic candidate genes. The diagnostic model and the 3 diagnostic candidate genes showed good diagnostic performances with AUC values >0.75 in both the training and the validation cohorts based on the ROC curve analyses. CIBERSORT analyses demonstrated positive correlation between the proportion of M0 macrophages in the valve tissues and the expression levels of TREM1, TNFRSF11B, and PGF.

Conclusion

Three pyroptosis-related genes (TREM1, TNFRSF11B and PGF) were identified as diagnostic biomarkers for CAVD. These pyroptosis genes and the pro-inflammatory microenvironment in the calcified valve tissues are potential therapeutic targets for alleviating CAVD.

Pyroptosis: A Promising Mechanism Linking SARS-CoV-2 Infection to Adverse Pregnancy Outcomes

Pregnancy is characterized by a delicate immune balance; therefore, infectious diseases might increase the risk of adverse pregnancy outcomes (APOs). Here, we hypothesize that pyroptosis, a unique cell death pathway mediated by the NLRP3 inflammasome, could link SARS-CoV-2 infection, inflammation, and APOs. Two blood samples were collected from 231 pregnant women at 11-13 weeks of gestation and in the perinatal period. At each time point, SARS-CoV-2 antibodies and neutralizing antibody titers were measured by ELISA and microneutralization (MN) assays, respectively. Plasmatic NLRP3 was determined by ELISA. Fourteen miRNAs selected for their role in inflammation and/or pregnancy were quantified by qPCR and further investigated by miRNA-gene target analysis. NLRP3 levels were positively associated with nine circulating miRNAs, of which miR-195-5p was increased only in MN+ women (p-value = 0.017). Pre-eclampsia was associated with a decrease in miR-106a-5p (p-value = 0.050). miR-106a-5p (p-value = 0.026) and miR-210-3p (p-value = 0.035) were increased in women with gestational diabetes. Women giving birth to small for gestational age babies had lower miR-106a-5p and miR-21-5p (p-values = 0.001 and 0.036, respectively), and higher miR-155-5p levels (p-value = 0.008). We also observed that neutralizing antibodies and NLRP3 concentrations could affect the association between APOs and miRNAs. Our findings suggest for the first time a possible link between COVID-19, NLRP3-mediated pyroptosis, inflammation, and APOs. Circulating miRNAs might be suitable candidates to gain a comprehensive view of this complex interplay.