Project description:Vascular calcification contributes to the cardiovascular morbidity and mortality of chronic kidney disease (CKD), but there is no approved treatment for vascular calcification. In this study, we report the role of STING in vascular calcification. To further investigate the molecular mechanism by which STING participates in vascular calcification, we performed high-throughput RNA-seq to identify the target gene of STING.
Project description:Background and Aims: The activation of stimulator of interferon genes (STING) and NOD-like receptors protein 3 (NLRP3) inflammasomes-mediated pyroptosis signaling pathways represent two distinct central mechanisms in liver disease. However, the interconnection between these two pathways and the epigenetic regulation of the STING-NLRP3 axis in hepatocyte pyroptosis during liver fibrosis remain unknown and is the focus of this study. Approach and Results: Liver fibrosis was induced in Sting knockout, Gasdermin D (Gsdmd) knockout mice, and in mice with hepatocyte-specific Nlrp3 deletion. RNA-sequencing, metabolomics, epigenetic compound screening system, and chromatin immunoprecipitation were utilized. STING and NLRP3 inflammasome signaling pathways were activated in cirrhotic livers but were suppressed by Sting knockout. Sting knockout also ameliorated hepatic pyroptosis, inflammation, and fibrosis in the murine cirrhotic model. In vitro, STING induced pyroptosis in primary murine hepatocytes via activating the NLRP3 inflammasome. H3K4-specific histone methyltransferase WD repeat-containing protein 5 (WDR5) and DOT1-like histone H3K79 methyltransferase (DOT1L) were identified to regulate NLRP3 expression in STING-overexpressed AML12 hepatocytes. WDR5/DOT1L-mediated histone methylation enhanced interferon regulatory transcription factor 3 (IRF3) binding to the Nlrp3 promoter and promoted STING-induced Nlrp3 transcription in hepatocytes. The RNA-sequencing and metabolomics analysis in murine livers and primary hepatocytes showed that metabolic reprogramming might participate in NLRP3-mediated hepatocyte pyroptosis and liver fibrosis. Moreover, hepatocyte-specific Nlrp3 deletion and downstream Gsdmd knockout attenuated hepatic pyroptosis, inflammation, and fibrosis in murine cirrhotic models. Conclusions: This study describes a novel epigenetic mechanism by which the STING-WDR5/DOT1L/IRF3-NLRP3 signaling pathway enhances hepatocyte pyroptosis and hepatic inflammation in liver fibrosis.
Project description:In this study, we repoort the protective effect of ursolic acid (UA) on vascular calcification in chronic kidney disease. To elucidate the molecular mechanism underlying the anti-vascular calcification effect of UA, we performed RNA-seq to identify the gene expresion under UA treatmment.
Project description:The goal of this study was to identify new mutations in the ENPP1 gene that produce infantile arterial calcification and fetal demise. A stillborn (proband) was diagnosed with infantile arterial calcification. Mutations in the ENPP1 gene account for ~80% of the cases of infantile arterial calcification through loss of function in both alleles (recessive inheritance).
Project description:Comparison of gene expression between Stat1+/- and Stat1-/- dermal fibroblasts or vascular smooth muscle cells after treatment with PDGF-BB for one hour.
Project description:Inflammasome, activated by pathogen-derived and host-derived danger signals, constitutes a multimolecular signaling complex that serves as a platform for caspase-1 (CASP1) activation and interleukin-1beta (IL1B) maturation. The activation of NLRP3 inflammasome requires two-step signals. The first “priming” signal (Signal 1) enhances gene expression of inflammasome components. The second “activation” signal (Signal 2) promotes the assembly of inflammasome components. Deregulated activation of NLRP3 inflammasome contributes to the pathological processes of Alzheimer’s disease (AD) and multiple sclerosis (MS). However, at present, the precise mechanism regulating NLRP3 inflammasome activation and deactivation remains largely unknown. By genome-wide gene expression profiling, we studied the molecular network of NLRP3 inflammasome activation-responsive genes in a human monocyte cell line THP-1 sequentially given two-step signals. We identified the set of 83 NLRP3 inflammasome activation-responsive genes. Among them, we found the NR4A nuclear receptor family NR4A1, NR4A2, and NR4A3, the EGR family EGR1, EGR2, and EGR3, the IkappaB family NFKBIZ, NFKBID, and NFKBIA as a key group of the genes that possibly constitute a negative feedback loop for shutting down inflammation following NLRP3 inflammasome activation. By molecular network analysis, we identified a complex network of NLRP3 inflammasome activation-responsive genes involved in cellular development and death, and immune and inflammatory responses, where transcription factors AP-1, NR4A, and EGR serve as a hub. Thus, NLRP3 inflammasome activation-responsive genes constitute the molecular network composed of a set of negative feedback regulators for prompt resolution of inflammation. To load the Signal 1 (S1), THP-1 cells were incubated for 3 hours in the culture medium with or without inclusion of 0.2 microgram/ml lipopolysaccharide (LPS). To load the Signal 2 (S2), they were incubated further for 2 hours in the culture medium with inclusion of 10 microM nigericin sodium salt dissolved in ethanol or the equal v/v% concentration of ethanol (vehicle), followed by processing for microarray analysis on Human Gene 1.0 ST Array (Affymetrix).
Project description:Pancreatic Gene Expression from Wild-Type, Stat1-Transgenic, and Stat1-CC-Transgenic Mice. This data was part of the set of data utilized to identify PARP9/DTX3L as a novel antiviral gene. Keywords: transgene state analysis RNA was extracted from the pancreas of 3 mice per genotype (wild-type, Stat1-Transgenic, Stat1-CC-Transgenic). Comparisons were made between Stat1-Transgenic and Stat1-CC-Transgenic mice.
Project description:The NLRP3 inflammasome is a multi-protein complex that triggers the activation of the inflammatory protein caspase-1 and the maturation of the cytokine IL-1 in response to microbes and other danger signals in host cells. Here, we sought a deeper understanding of how the NLRP3 inflammasome is regulated. We found that inflammasome activation induced the Src family kinase Lyn to phosphorylate NLRP3 at Tyr918, and that this phosphorylation of NLRP3 correlated with a subsequent increase in its ubiquitination, which facilitated its proteasome-mediated degradation. NLRP3 tyrosine phosphorylation and ubiquitination was abrogated in Lyn-deficient macrophages, which produced increased amounts of IL-1. Furthermore, mice lacking Lyn were highly susceptible to LPS-induced septic shock in an NLRP3-dependent manner. Our data demonstrate that Lyn-mediated tyrosine phosphorylation of NLRP3 is a prerequisite for its ubiquitination, thus dampening NLRP3 inflammasome activity.
Project description:Autophagy and autophagy-associated genes are closely linked to NLRP3-mediated inflammation in inflammatory disorders. This study determined that the functions of CCDC50, the novel autophagy receptor, in regulating the activation of NLRP3 inflammasome and associated inflammatory diseases. We performed transcriptome profiling (RNA-seq) and quantitative reverse transcription polymerase chain reaction (qRT–PCR) in shCtrl and shCCDC50 cells to evaluate the inflammatory responses regulated by CCDC50. The deep sequencing results showed that CCDC50 defciency caused increased NLRP3 inflammasome assembly and upregulation of associated disease pathways.