Impacts of Salmonella enteritidis Infection on Liver Transcriptome in Broilers
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ABSTRACT: To provide insight into the systemic metabolic effects of S. enteritidis infection, liver samples were harvested 10 days post infection from broiler hens. Hepatic global gene expression levels were assessed using a chicken 44K Agilent microarray. Forty-four genes were differentially expressed at a significance level of q-value < 0.05. One hundred eighty-three genes were differentially expressed at a suggestive significance level of q-value < 0.1. A predominance of down-regulation existed among significantly differentially expressed genes. A cell morphology, cell cycle, organismal injury and abnormalities network and a metabolic disease, cardiovascular system development and function, and urological disease network were created from the differentially expressed genes. Apoptosis, electron transport, peptidase activity, vein constriction, cell differentiation, IL-2 signaling, Jak-Stat signaling, B-cell receptor signaling, GDP/GTP exchange, and cytokine suppression were among the functions of the differentially expressed genes that were down-regulated in response to S. enteritidis. The effects of S. enteritidis infection on the liver transcriptome profiles of broilers reflect a predominance of down-regulation of genes involved with metabolic, cell morphology, cell cycle, urological disease, and organismal injury functions. These results provide insight into important systemic metabolic mechanisms that are active in the chicken liver in response to S. enteritidis infection. Sixteen broiler hens of approximately 5 months (8 challenged orally with 1x108 S. enteritidis on each of three sequential days and 8 mock-challenged with phosphate buffered saline) were used. Livers were harvested at 10 days post infection and stored in RNALater (Ambion).
Project description:To provide insight into the systemic metabolic effects of S. enteritidis infection, liver samples were harvested 10 days post infection from broiler hens. Hepatic global gene expression levels were assessed using a chicken 44K Agilent microarray. Forty-four genes were differentially expressed at a significance level of q-value < 0.05. One hundred eighty-three genes were differentially expressed at a suggestive significance level of q-value < 0.1. A predominance of down-regulation existed among significantly differentially expressed genes. A cell morphology, cell cycle, organismal injury and abnormalities network and a metabolic disease, cardiovascular system development and function, and urological disease network were created from the differentially expressed genes. Apoptosis, electron transport, peptidase activity, vein constriction, cell differentiation, IL-2 signaling, Jak-Stat signaling, B-cell receptor signaling, GDP/GTP exchange, and cytokine suppression were among the functions of the differentially expressed genes that were down-regulated in response to S. enteritidis. The effects of S. enteritidis infection on the liver transcriptome profiles of broilers reflect a predominance of down-regulation of genes involved with metabolic, cell morphology, cell cycle, urological disease, and organismal injury functions. These results provide insight into important systemic metabolic mechanisms that are active in the chicken liver in response to S. enteritidis infection.
Project description:The liver plays a critical role in avian reproduction as it is the primary site of de novo lipogenesis and yolk precursor synthesis. Broiler breeder hens, the parents of commercial broiler chickens, often experience poor reproductive efficiency primarily due to declining egg production beginning around 45 weeks of age. Metformin, an antidiabetic drug, exerts its primary effects in the liver by increasing insulin sensitivity and reducing hepatic glucose production in humans. This study aimed to characterize the liver transcriptomic profile of broiler breeder hens supplemented with metformin in the diet at 0 or 75 mg/kg body weight for 40 weeks (25-65 weeks of age; n=45 hens/treatment). Liver tissue was collected from a subset of hens (n=12 hens/treatment group) at 65 weeks of age, RNA was extracted and sequenced using next-generation sequencing. Differential gene abundance analysis revealed that metformin treatment led to the most significant changes in gene expression, with 552 genes differentially expressed compared to the control group. Further transcriptomic analysis highlighted increased expression of genes related to estrogen-stimulated yolk precursor synthesis, insulin-stimulated de novo lipogenesis, and AMPK-mediated glucose homeostasis. qPCR analysis revealed increased expression of ESR1, APOB, APOV1, VTG2, ADIPOQ, ADIPOR2 and ACACA mRNA and decreased expression of PCK1 mRNA validating the transcriptomic data. Collectively, the present study suggests that metformin supplementation supports prolonged egg production in aging broiler breeder hens by sustaining yolk precursor and fatty acid synthesis that are typically diminished in aging broiler breeder hens.
Project description:In the two F8 advanced crosses of broiler by Leghorn and broiler by Fayoumi, birds at day 1 were challenged with Salmonella enteritidis (SE). Spleen were collected at day 7 and 8. SE bacterial load in spleen were measured. Based on the bacterial load, birds were divided into high and low SE load groups. Keywords: Salmonella enteritidis challenge
Project description:Intense selective breeding of broiler breeds of chickens has resulted in suboptimal egg production in broiler breeder hens. Ad libitum feeding which leads to excessive and disorganized follicular growth exacerbates this reproductive phenotype. One strategy used to improve broiler breeder hen reproductive efficiency is restricted feeding. In this study, we sought to identify transcriptional changes which translate level of dietary intake to increased follicle selection. Broiler breeder hens were raised according to commercial guidelines until 28 weeks of age and then randomly assigned to an ad libitum diet (FF) or continued on a restricted diet (RF) for 6 weeks. Following dietary treatment, granulosa cells from growing 6-8 mm follicles from FF hens (n=3) and RF hens (n=3) were collected, RNA was extracted, and samples were processed for RNA-sequencing on Illumina NextSeq 500. Transcriptomes of granulosa cells from 6-8 mm follicles were sequenced to identify transcriptional differences in the population from which follicles are selected into the preovulatory stage. FastQ files were first processed through trim-galore and reads were aligned to the Galgal6 genome using the RNA-seq aligner, STAR. A cluster analysis using hclust in R identified a FF sample as an outlier and this sample was removed from the analysis. Differential expression analysis was conducted using DeSEQ2 and resulted in 350 differentially expressed genes. Several genes involved in follicle selection were upregulated in prehierarchal follicles of FF hens, suggesting an effect of dietary treatment at early stages in follicle development.
Project description:Investigation of whole genome gene expression level changes in Salmonella enterica serova Enteritidis and Typhimurium under chlorine treatment An eighteen chip study using total RNA isolated from three separate cultures of (1) S. Enteritidis in BHI broth (2) S. Typhimurium in BHI broth (3) S. Enteritidis in BHI broth w/ 130 ppm chlorine (4) S. Typhimurium in BHI w/ 130 ppm chlorine (5) S. Enteritidis in BHI broth w/ 390 ppm (6) S. Typhimurium in BHI broth w/ 390 ppm. Each chip measures the expression level of 5,027 ORFs covering the whole genome of S. Enteritidis and S. Typhimurium.
Project description:The response of chicken to non-typhoidal Salmonella infection is becoming well characterised but the role of particular cell types in this response is still far from being understood. Therefore, in this study we characterised the response of chicken embryo fibroblasts (CEFs) to infection with two different S. Enteritidis strains by microarray analysis. The expression of chicken genes identified as significantly up- or down-regulated (≥3-fold) by microarray analysis was verified by real-time PCR followed by functional classification of the genes and prediction of interactions between the proteins using Gene Ontology and STRING Database. Finally the expression of the newly identified genes was tested in HD11 macrophages and in vivo in chickens. Altogether 19 genes were induced in CEFs after S. Enteritidis infection. Twelve of them were also induced in HD11 macrophages and thirteen in the caecum of orally infected chickens. The majority of these genes were assigned different functions in the immune response, however five of them (LOC101750351, K123, BU460569, MOBKL2C and G0S2) have not been associated with the response of chicken to Salmonella infection so far. K123 and G0S2 were the only 'non-immune' genes inducible by S. Enteritidis in fibroblasts, HD11 macrophages and in the caecum after oral infection. The function of K123 is unknown but G0S2 is involved in lipid metabolism and in β-oxidation of fatty acids in mitochondria. Increased levels of G0S2 might decrease the availability of fatty acids to mitochondria. In non-professional phagocytes such as CEFs, this may lead to the dysfunction of mitochondria, apoptosis of CEFs and release of intracellular Salmonella. In professional phagocytes, G0S2 might be involved in the control of mitochondrial respiration, resulting in a decrease of reactive oxygen species as respiration by-products and lower damage to tissue. In this study we were interested whether chicken embryo fibroblast (CEFs) respond to S. Enteritidis infection and to what extent their response differs from that of other cells and caecal tissue. To address this, we characterised the gene expression of CEFs after infection with two different wild-type S. Enteritidis strains of poultry origin - SE 147 and SE 11 - using Agilen custom 8×15K microarrays. In total, 13,681 probes were designed to characterise the expression of ~9,000 transcripts of Gallus gallus.
Project description:Broiler breeder hens given ad libitum access to feed have excessive ovarian follicle development with poor reproductive outcome. One strategy to improve their reproductive capacity is by restricting their feed intake. In this study, we sequenced the liver transcriptomes of hens fed ad libitum (FF, n=3) and hens given a restricted fed diet (RF, n=3) to get insight into possible signaling pathways affected by dietary treatment. Hens were reared according to commercial guidelines until 38 weeks of age, when they were assigned to either FF or continued on RF for 6 weeks. Liver mRNA samples from three hens in each group were sequenced using the Illumina HiSeq 2000/2500 technology at a depth of 100 bp. The sequencing quality of the data was determined using FastQC. Reads were aligned to UCSC Galgal4 using Tophat (v2.0.13) and transcripts were counted using cuffdiff (v.2.2.1). A multidimensional scaling plot (MDS plot) was generated to evaluate the variance among biological replicates and identified one FF hen as a sample outlier and this animal was removed from the analysis. Differential gene expression analysis was conducted using edgeR and yielded 120 differentially expressed genes. This study identified transcriptional differences in the livers of FF and RF hens which may signal metabolic status to the ovary.
Project description:Broiler chicken production is crucial to meet the increasing global food demand. Hyperphagic and obese broiler breeder hens have a short production cycle, which is challenged by age-associated egg quality and fertility decline, affecting hatchability. A fertilized egg is a comprehensive set of essential elements to nurture and develop a healthy chick. Egg albumin occupies most of the egg content, which is synthesized and secreted by the magnum. The genetic regulation of albumin biosynthesis in broiler breeder hens and its alteration with age might reveal the genetic marker that will produce quality eggs in subsequent generations. Hence, the objective of the study is to determine the differentially expressed genes (DEGs) and pathways involved in albumin biosynthesis in the magnum (young vs aged). The magnum tissues were collected from the broiler breeder hens at peak production, identified as the young group (35 weeks, N=30), and from the declined production, recognized as the aged group (50 weeks, N=30). Five samples from each group (n=5) were used for RNA sequencing and analyzed to get DEGs and associated pathways. The significantly upregulated genes with a putative function in quality egg formation were confirmed using qPCR. Seventy-five up-regulated and 52 down-regulated genes were determined. The top 20 most upregulated genes and top 20 most downregulated genes, based on their putative function, were categorized into five groups: egg white synthesizing (AMDHD1, FER, CTNNA3), molecular communication (VAPA), oviduct tissue regeneration (ADAM19, CFAP100, AMD1, TM4SF19, SLC39A13, VMO1), and defense (ZBTB46, STAM2, OVoDA3). “Post-translational protein phosphorylation” was the most significantly enriched Reactome pathway involving DNAJC3, PPP3CA, TF, SPARCL1, PDIA6, SGPP2, HSP90B1, and PNPLA2 genes. The study successfully identified DEGs, genetic networks, and pathways that can be used as genetic markers to select quality egg producing broiler breeder hens.
Project description:Objective: Reg3g has been proposed to have a protective role against infection due to its bactericidal effect on Gram-positive bacteria, but evidence from in vivo studies is lacking. Therefore we generated a Reg3g-/- mouse, to determine its role in intestinal homeostasis and protection against experimental infection. Methods: Reg3g-/- mice were phenotyped using histological methods and a range of innate and immune markers. To investigate the antimicrobial role of Reg3g we experimentally infected mice with Gram-positive Listeria monocytogenes and Gram-negative Salmonella entertitidis and measured translocated bacteria, mucosal and systemic markers of infection. Results: Reg3g-/- mice display altered ileal mucus distribution and increased bacterial contact with the epithelium. , concomitant with This increased the inflammatory status in of the ileal mucosa and increased expression of Il-22, myeloperoxidase (MPO) and serum chemokines in serum. In response to infection, Reg3g-/- mice showed transcriptome changes and elevated levels of mucosal MPO in the ileum, but no increased bacterial translocation to the organs. Conclusions: Reg3g is equally distributed throughout the mucus of wild type (wt) mice and its absence results in an altered distribution of the ileal mucus. Reg3g deficiency also results resulted in increased bacterial contact with the epithelium and heightened inflammatory responses in the ileal mucosa. We propose that Reg3g binds pathogens suggesting it and contributes to mucus barrier function by ensnaring bacteria. Compared to wt mice, Reg3g-/- mice infected with S. enteritidis and L. monocytogenes show an increase of mucosal inflammatory markers indicating the protective, anti-microbial roles of Reg3g in defence against both Gram-positive and -negative bacteria. This study was set up according to a one-treatment, one-control design; treatments were inoculation with either Listeria monocytogenes or Salmonella enteritidis bacterial pathogens. The study results contain transcriptional profiles from infected and sham-infected control C57Bl/6 mice. In total, this study includes data from 2 treatments and 1 control of (pooled) wild-type C57Bl/6 mice and Reg3g-/- KO mutant C57Bl/6 mice = 6 arrays.
Project description:Salmonella infections are among the most common foodborne diseases worldwide. The Enteritidis and Dublin serovars of Salmonella enterica are closely related yet they differ significantly in pathogenicity and epidemiology. Enteritidis is a broad-host-range serovar that commonly causes gastroenteritis and infrequently causes invasive disease in humans. Dublin mainly colonizes cattle but upon infecting humans often results in invasive disease. The aim of this work was to elucidate the molecular factors responsible for the differential pathogenic behavior between both serovars. We performed a quantitative proteomic comparative analysis between one clinical isolate of each serovar grown in vitro under gut mimicking conditions (GMC). Compared to S. Enteritidis, the S. Dublin proteome was enriched in proteins linked to response to several stress conditions, such as those encountered during host infection, as well as to virulence. The S. Enteritidis proteome contained proteins related to central anaerobic metabolism pathways that were undetected in S. Dublin. Similar differences were also found at the transcriptional level, as mRNA levels correlated with proteomic results for 17 of the 20 genes tested in 4 natural isolates of each serovar grown in GMC. This work reveals proteomic differences between two Salmonella serovars with markedly different invasive and host-range characteristics, grown in an infection relevant condition, which were not evident in previous comparative genomic analyses.