Project description:Lactobacillus acidophilus reduces the susceptibility of Citrobacter rodentium induced by bowel preparation with polyethylene glycol
Project description:Helicobacter pylori causes chronic gastritis and avoids elimination by the immune system of the infected host. The commensal bacterium Lactobacillus acidophilus has been reported to exert beneficial effects as a supplement during H. pylori eradication therapy. In the present study, we applied whole genome microarray analysis to compare the immune response induced in murine bone marrow derived macrophages (BMDM) stimulated with L. acidophilus, H. pylori, or with both bacteria in combination Microarray expression profiling was performed to analyze stimulation of bone marrow derived macrophages with Helicobacter pylori 251, Lactobacillus acidophilus NCFM or Lactobacillus acidophilus NCFM co-stimulated with Helicobacter pylori 251 were analyzed 5 hours after infection.
Project description:Background: Beneficial microbes can be actors in maintaining or stimulating barrier function, and may counteract pathogen-infection. Lactobacilli are particularly recognized for enhancing intestinal barrier function and to confer protective effects against multiresistant pathogens. Various L. acidophilus strains support intestinal immune barrier function and have been shown to improve resistance to pathogens. Although less extensively studied than beneficial bacteria, other food-based ingredients that can contribute to strengthening barrier function are dietary fibers. For instance, inulin and fructooligosaccharides (FOS) have recently been shown to enhance barrier function and protect against barrier dysfunction. Effects of these ingredients on intestinal barrier function were evaluated by quantifying regulation of gene expression by microarray. Methods: Caco-2 cells were incubated with probiotic strains or inulin-type fibers for 6 hours, total RNA was extracted and Affymterix Human Gene 1.1 ST arrays were used to analyze the gene expression profiles. Results: Only L. acidophilus modulated a group of 26 genes related to tight-junctions. Inulin-type fructans, L. brevis W63 and L. casei W56 regulated other genes, unrelated to tight junctions. L. acidophilus also had unique effects on a group of 6 genes regulating epithelial phenotype towards follicle-associated epithelium. L. acidophilus W37 was therefore selected for a challenge with STM and prevented STM-induced barrier disruption and decreased secretion of IL-8. L. acidophilus W37 increases TEER and can protect against STM induced disruption of gut epithelial cells integrity in vitro. Conclusion: Our results suggest that selection of specific bacterial strains for enforcing barrier function may be a promising strategy to reduce or prevent STM infections.
Project description:This randomized clinical trial studies how well neomycin and metronidazole hydrochloride with or without polyethylene glycol work in reducing infection in patients undergoing elective colorectal surgery. Polyethylene glycol, may draw water from the body into the colon, flushing out the contents of the colon. Antibiotics, like neomycin and metronidazole hydrochloride, may stop bacteria from growing. It is not yet known whether it’s better to give preoperative neomycin and metronidazole hydrochloride with or without polyethylene glycol in reducing surgical site infection after colorectal surgery.
Project description:Recent reports have shown that Gram-positive bacteria actively secrete spherical nanometer-sized proteolipid membrane vesicles (MVs) into their surroundings. Though MVs have been implicated in a broad range of biological functions, few studies have been conducted to examine their potential as delivery vehicles of antimicrobials. Here, we investigate the natural ability of Lactobacillus acidophilus MVs to carry and deliver bacteriocin peptides to the opportunistic pathogen, Lactobacillus delbrueckii. We demonstrate that upon treatment with lactacin B-inducing peptide the proteome of the secreted MVs is enriched in putative bacteriocins encoded by the lab operon. Further, we show that purified MVs inhibit growth and form membrane pores in L. delbrueckii, which is confirmed using a number of microscopy techniques and spectrophotometry. These results show that L. acidophilus MVs serve as conduits for antimicrobials to competing cells in the environment, suggesting a potential role for MVs in complex communities such as the gut microbiome. With the potential for controlling their payload through microbial engineering, MVs produced by L. acidophilus may be an interesting platform for effecting change in complex microbial communities or aiding in the development of new biomedical therapeutics.
Project description:Purpose: The goals of this study are to understand transcriptional changes in the roots of drought-tolerant and sensitive sesame genotypes using PEG (Polyethylene glycol) induced osmotic stress.
Project description:Gene expression in THP-1 cells on treatment with Lactobacillus acidophilus, Bacillus clausii and Bifidobacterium bifidum at MOI of 1 for 6 hours.
Project description:Gene expression in RAW 264.7 cells on treatment with Lactobacillus acidophilus, Bacillus clausii and Bifidobacterium bifidum at MOI of 1 for 6 hours.
