Project description:Purpose: To understand the metabolic mechanism of Lactobacillus salivarius Ren in raffinose Methods: Samples of Lactobacillus salivarius Ren grown in glucose and raffinose were sequenced on the Illumina Hiseq platform. Three independent biological replicates were generated, including a total of six samples. Results: Raw data were firstly processed through in-house perl scripts to generate clean data, and then clean date were mapped to the reference genome, getting about 8-10 million total mapped reads per sample.
Project description:This experiment compared the gene expression profiles of Lactobacillus salivarius UCC118 (wild type, control) and UCC118 with the SrtA gene deleted. Following exposure of both strains to Caco-2 epithelial cells.
Project description:M cells are the main site of bacterial translocation in the intestine. We used the in vitro M cell model to study the effect of the commensal bacteria; Lactobacillus salivarius, Eschericha coli and Bacteroides fragilis, on M cell gene expression. Bacterial translocation across the gut mucosa has traditionally been based on the detection of commensals in the mesenteric lymph node. Differential rates of commensal translocation have been reported in vivo, however fewer studies have examined translocation of commensals at the level of the gut epithelial M cell. In this study we employed an in vitro M cell model to quantify translocation of various bacteria. C2BBe1 cells were differentiated into M cells and the gene expression profile and transport kinetics of different bacterial strains, namely Lactobacillus salivarius, Escherichia coli, and Bacteroides fragilis, was assessed. For comparison with M cell uptake, the THP-1 monocytic cell line was used to analyze bacterial internalization and resulting cytokine production. The commensal bacterial strains were translocated across M cells with different efficiencies; E. coli and B. fragilis translocated with equal efficiency while L. salivarius translocated with less efficiency. In contrast, L. salivarius was internalized by THP-1 cells to a higher degree than B. fragilis or E. coli and was associated with a different cytokine profile. Microarray analysis showed both common and differential gene expression amongst the bacteria and control polystyrene beads. In the presence of bacteria, but not beads, upregulated genes were mainly involved in transcription regulation and dephosphorylation, e.g. EGR1, JUN; whereas proinflammatory and stress response genes were primarily upregulated by E. coli and B. fragilis, but not L. salivarius nor beads, e.g. IL8, TNFAIP3. These results demonstrate that M cells have the ability to discriminate between different commensal bacteria and modify subsequent immune responses. C2bbe1 cells were converted to M cells (C2M) following 21 days of culture on Transwells in the presence of Raji B cells. C2M cells were co-cultured alone, Lactobacillus salivarius, Eschericha coli, Bacteroides fragilis and control beads. Total RNA was extracted and processed for Affymetrix array hybridisation
Project description:Lactobacillus salivarius is a member of the indigenous microbiota of the human gastrointestinal tract (GIT). Tolerance to bile stress is crucial for intestinal lactobacilli to survive in the GIT and to exert their beneficial actions. In this work, the Next-Generation Sequencing platform Illumina HiSeq 2000 was used to investigate the global response to bile in L. salivarius Ren, a potential probiotic strain isolated from a healthy centenarian. In the presence of 0.75 g liter-1 oxgall, the transcription of nearly 200 genes was detected to be associated with bile stress, including genes involved in carbohydrate and amino acid metabolism, cell envelope and fatty acid biogenesis, transcription and translation. This study improves our understanding on bile stress response in L. salivarius Ren.
Project description:Adult Sprague Dawley rats were treated i.g. with 50 mg/kg alpha-naphthylisothiocyanate (ANIT) or vehicle (corn oil). Hepatobiliary liver injury occurred at 24 h postdose in ANIT rats with repair at 120h. Livers were extracted from rats at 24h and 120 h post ANIT exposure. This study investigated differences in mRNA expression between the injury and repair phases in the context of ANIT exposure.
