Intestinal Salmonella Typhimurium infection leads to miR-29a induced Caveolin 2 regulation
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ABSTRACT:
ORGANISM(S): Sus scrofa
PROVIDER: GSE40805 | GEO | 2013/06/25
SECONDARY ACCESSION(S): PRJNA175011
REPOSITORIES: GEO
Similar Datasets
Project description:BackgroundSalmonella are able to modulate host cell functions facilitating both uptake and resistance to cellular host defence mechanisms. While interactions between bacterial modulators and cellular proteins have been the main focus of Salmonella research, relatively little is known about mammalian gene regulation in response to Salmonella infection. A major class of mammalian gene modulators consists of microRNAs. For our study we examined interactions of microRNAs and regulated mRNAs in mammalian intestinal Salmonella infections using a piglet model.Methodology/principal findingsAfter performing microRNA as well as mRNA specific microarray analysis of ileal samples from Salmonella infected as well as control piglets, we integrated expression analysis with target prediction identifying microRNAs that mainly regulate focal adhesion as well as actin cytoskeleton pathways. Particular attention was given to miR-29a, which was involved in most interactions including Caveolin 2. RT-qPCR experiments verified up-regulation of miR-29a after infection while its predicted target Caveolin 2 was significantly down-regulated as examined by transcript and protein detection. Reporter gene assays as well as RNAi experiments confirmed Caveolin 2 to be a miR-29a target. Knock-down of Caveolin 2 in intestinal epithelial cells resulted in retarded proliferation as well as increased bacterial uptake. In addition, our experiments showed that Caveolin 2 regulates the activation of the small Rho GTPase CDC42 but apparently not RAC1 in human intestinal cells.Conclusions/significanceOur study outlines for the first time important regulation pathways in intestinal Salmonella infection pointing out that focal adhesion and organisation of actin cytoskeleton are regulated by microRNAs. Functional relevance is shown by miR-29a mediated Caveolin 2 regulation, modulating the activation state of CDC42. Further analysis of examined interactions may support the discovery of novel strategies impairing the uptake of intracellular pathogens.
| S-EPMC3691122 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2013-06-25 | E-GEOD-40805 | biostudies-arrayexpress
Project description:The host response to S.typhimurium infections in ileum was studied after infection of piglets. mRNA and miRNA expression studies were performed to identify interactions of miRNAs and regulated mRNAs in context of mammalian intestinal Salmonella infection using a piglet model.
2013-06-25 | GSE40804 | GEO
Project description:The host response to S.typhimurium infections in ileum was studied after infection of piglets. mRNA and miRNA expression studies were performed to identify interactions of miRNAs and regulated mRNAs in context of mammalian intestinal Salmonella infection using a piglet model.
2013-06-25 | GSE40803 | GEO
Project description:The host response to S.typhimurium infections in ileum was studied after infection of piglets. mRNA and miRNA expression studies were performed to identify interactions of miRNAs and regulated mRNAs in context of mammalian intestinal Salmonella infection using a piglet model. Intestinal samples (~ 2 cm circle segments) were taken at time points 3h, 3d and 28d post infection from ileum of ten S.typhimurium infected piglets (S), ten S.typhimurium infected piglets and additional treated with probiotic strain E.faecium NCIMB 10415 (SP) and five healthy control piglets(C) (EUROC x Pietrain). The piglets were weaned at the age of 28 days and infected with S. typhimurium. Samples were quick-frozen in liquid nitrogen and stored at -80 M-BM-0C. In order to obtain representative measurements in each intestinal locus, three cross sections of approximately 2 mm out of the 2 cm segment of frozen intestine were examined. These 3 sections were pooled and total RNA was isolated from samples using an automated homogenizer (FastPrep Instrument, MP Biomedicals, Heidelberg, Germany) and the mirVana miRNA Isolation Kit (Applied Biosystems, Darmstadt, Germany), according to the manufacturerM-bM-^@M-^Ys protocol. The RNA quality and quantity of all samples were proven using the Agilent 2100 Bioanalyzer and the RNA 6000 Nano Kits (Agilent, Waldbronn, Germany) and the Nanodrop 1000 Spectrophotometer (Thermo Scientific, MA, USA). For microarray analysis pooled samples of each experimental group were prepared ana partes aequalis from individually isolated total RNA samples, which werde collected at the same time point in each group. Common reference was designed from equal amounts of total RNA of each pool and additional total RNA from ascending colon.
2013-06-25 | E-GEOD-40803 | biostudies-arrayexpress
Project description:The host response to S.typhimurium infections in ileum was studied after infection of piglets. mRNA and miRNA expression studies were performed to identify interactions of miRNAs and regulated mRNAs in context of mammalian intestinal Salmonella infection using a piglet model. Intestinal samples (~ 2 cm circle segments) were taken at time points 3h, 3d and 28d post infection from ileum of ten S.typhimurium infected piglets (S), ten S.typhimurium infected piglets and additional treated with probiotic strain E.faecium NCIMB 10415 (SP) and five healthy control piglets(C) (EUROC x Pietrain). The piglets were weaned at the age of 28 days and infected with S. typhimurium. Samples were quick-frozen in liquid nitrogen and stored at -80 M-BM-0C. In order to obtain representative measurements in each intestinal locus, three cross sections of approximately 2 mm out of the 2 cm segment of frozen intestine were examined. These 3 sections were pooled and total RNA was isolated from samples using an automated homogenizer (FastPrep Instrument, MP Biomedicals, Heidelberg, Germany) and the mirVana miRNA Isolation Kit (Applied Biosystems, Darmstadt, Germany), according to the manufacturerM-bM-^@M-^Ys protocol. The RNA quality and quantity of all samples were proven using the Agilent 2100 Bioanalyzer and the RNA 6000 Nano Kits (Agilent, Waldbronn, Germany) and the Nanodrop 1000 Spectrophotometer (Thermo Scientific, MA, USA). For microarray analysis pooled samples of each experimental group were prepared ana partes aequalis from individually isolated total RNA samples, which were collected at the same time point in each group. Common reference was designed from equal amounts of total RNA of each pool and additional total RNA from ascending colon.
2013-06-25 | E-GEOD-40804 | biostudies-arrayexpress
Project description:The ability of Salmonella typhimurium to enter intestinal epithelial cells constitutes a crucial step in pathogenesis. Salmonella invasion of the intestinal epithelium requires bacterial type three secretion system. Type three secretion system is a transport device that injects virulence proteins, called effectors, to paralyze or reprogram the eukaryotic cells. Avirulence factor for Salmonella (AvrA) is a Salmonella effector that inhibits the host's inflammatory responses. The mechanism by which AvrA modulates host cell signaling is not entirely clear. p53 is situated at the crossroads of a network of signaling pathways that are essential for genotoxic and nongenotoxic stress responses. We hypothesized that Salmonella infection activates the p53 pathway. We demonstrated that Salmonella infection increased p53 acetylation. Cells infected with AvrA-sufficient Salmonella have increased p53 acetylation, whereas cells infected with AvrA-deficient Salmonella have less p53 acetylation. In a cell-free system, AvrA possessed acetyltransferase activity and used p53 as a substrate. AvrA expression increased p53 transcriptional activity and induced cell cycle arrest. HCT116 p53-/- cells had less inflammatory responses. In a mouse model of Salmonella infection, intestinal epithelial p53 acetylation was increased by AvrA expression. Our studies provide novel mechanistic evidence that Salmonella modulates the p53 pathway during intestinal inflammation and infection.
| S-EPMC2867426 | biostudies-other
Project description:BackgroundIntestinal fibrosis is a common and serious complication of Crohn's disease characterized by the accumulation of fibroblasts, deposition of extracellular matrix, and formation of scar tissue. Although many factors including cytokines and proteases contribute to the development of intestinal fibrosis, the initiating mechanisms and the complex interplay between these factors remain unclear.MethodsChronic infection of mice with Salmonella enterica serovar Typhimurium was used to induce intestinal fibrosis. A murine protease-specific CLIP-CHIP microarray analysis was employed to assess regulation of proteases and protease inhibitors. To confirm up- or downregulation during fibrosis, we performed quantitative real-time polymerase chain reaction (PCR) and immunohistochemical stainings in mouse tissue and tissue from patients with inflammatory bowel disease. In vitro infections were used to demonstrate a direct effect of bacterial infection in the regulation of proteases.ResultsMice develop severe and persistent intestinal fibrosis upon chronic infection with Salmonella enterica serovar Typhimurium, mimicking the pathology of human disease. Microarray analyses revealed 56 up- and 40 downregulated proteases and protease inhibitors in fibrotic cecal tissue. Various matrix metalloproteases, serine proteases, cysteine proteases, and protease inhibitors were regulated in the fibrotic tissue, 22 of which were confirmed by quantitative real-time PCR. Proteases demonstrated site-specific staining patterns in intestinal fibrotic tissue from mice and in tissue from human inflammatory bowel disease patients. Finally, we show in vitro that Salmonella infection directly induces protease expression in macrophages and epithelial cells but not in fibroblasts.ConclusionsIn summary, we show that chronic Salmonella infection regulates proteases and protease inhibitors during tissue fibrosis in vivo and in vitro, and therefore this model is well suited to investigating the role of proteases in intestinal fibrosis.
| S-EPMC6749888 | biostudies-literature
Project description:To cause a systemic infection, Salmonella must respond to many environmental cues during mouse infection and express specific subsets of genes in a temporal and spatial manner, but the regulatory pathways are poorly established. To unravel how micro-environmental signals are processed and integrated into coordinated action, we constructed in-frame non-polar deletions of 83 regulators inferred to play a role in Salmonella enteriditis Typhimurium (STM) virulence and tested them in three virulence assays (intraperitoneal [i.p.], and intragastric [i.g.] infection in BALB/c mice, and persistence in 129X1/SvJ mice). Overall, 35 regulators were identified whose absence attenuated virulence in at least one assay, and of those, 14 regulators were required for systemic mouse infection, the most stringent virulence assay. As a first step towards understanding the interplay between a pathogen and its host from a systems biology standpoint, we focused on these 14 genes. Transcriptional profiles were obtained for deletions of each of these 14 regulators grown under four different environmental conditions. These results, as well as publicly available transcriptional profiles, were analyzed using both network inference and cluster analysis algorithms. The analysis predicts a regulatory network in which all 14 regulators control the same set of genes necessary for Salmonella to cause systemic infection. We tested the regulatory model by expressing a subset of the regulators in trans and monitoring transcription of 7 known virulence factors located within Salmonella pathogenicity island 2 (SPI-2). These experiments validated the regulatory model and showed that the response regulator SsrB and the MarR type regulator, SlyA, are the terminal regulators in a cascade that integrates multiple signals. Furthermore, experiments to demonstrate epistatic relationships showed that SsrB can replace SlyA and, in some cases, SlyA can replace SsrB for expression of SPI-2 encoded virulence factors.
| S-EPMC2639726 | biostudies-literature
Project description:A number of studies have shown an association of pathogens with caveolae. To this date, however, there are no studies showing a role for caveolin-1 in modulating immune responses against pathogens. Interestingly, expression of caveolin-1 has been shown to occur in a regulated manner in immune cells in response to lipopolysaccharide (LPS). Here, we sought to determine the role of caveolin-1 (Cav-1) expression in Salmonella pathogenesis. Cav-1(-/-) mice displayed a significant decrease in survival when challenged with Salmonella enterica serovar Typhimurium. Spleen and tissue burdens were significantly higher in Cav-1(-/-) mice. However, infection of Cav-1(-/-) macrophages with serovar Typhimurium did not result in differences in bacterial invasion. In addition, Cav-1(-/-) mice displayed increased production of inflammatory cytokines, chemokines, and nitric oxide. Regardless of this, Cav-1(-/-) mice were unable to control the systemic infection of Salmonella. The increased chemokine production in Cav-1(-/-) mice resulted in greater infiltration of neutrophils into granulomas but did not alter the number of granulomas present. This was accompanied by increased necrosis in the liver. However, Cav-1(-/-) macrophages displayed increased inflammatory responses and increased nitric oxide production in vitro in response to Salmonella LPS. These results show that caveolin-1 plays a key role in regulating anti-inflammatory responses in macrophages. Taken together, these data suggest that the increased production of toxic mediators from macrophages lacking caveolin-1 is likely to be responsible for the marked susceptibility of caveolin-1-deficient mice to S. enterica serovar Typhimurium.
| S-EPMC1698056 | biostudies-literature