Project description:The hypocholesterolemic effect of probiotics has been observed, but the molecular mechanism of probiotic-host interaction is still obscure. In this study, DNA microarray technology was used to explore the gene expression profile of liver of hypercholesterolemic rats caused by administration of probiotic Lactobacillus casei Zhang, which can decrease the serum triglyceride, low-density lipoprotein cholesterol, hepatic cholesterol and triglyceride of hypercholesterolemic rats. Six liver samples in high fat and probiotic treated group (3 samples in each group) were randomly selected for RNA isolation and microarray hybridization, the 3 samples in high fat group were used as control.
Project description:The hypocholesterolemic effect of probiotics has been observed, but the molecular mechanism of probiotic-host interaction is still obscure. In this study, DNA microarray technology was used to explore the gene expression profile of liver of hypercholesterolemic rats caused by administration of probiotic Lactobacillus casei Zhang, which can decrease the serum triglyceride, low-density lipoprotein cholesterol, hepatic cholesterol and triglyceride of hypercholesterolemic rats.
Project description:Lactic acid bacteria have been used as starter strains in the production of fermented dairy products for centuries. Lactobacillus acidophilus is a widely recognized probiotic bacteria commonly added to yogurt and used in dietary supplements. In this study, a whole genome microarray was employed to monitor gene expression of L. acidophilus cells propagated in 11% skim milk (SM) during early, mid and late logarithmic phase, and stationary phase. Approximately 21% of 1,864 ORFs were differentially expressed at least in one time point. Genes differentially expressed in SM included several members of the proteolytic enzyme system. Expression of prtP (proteinase precursor) and prtM (maturase) increased over time as well as several peptidases and transport systems. Expression of Opp1 (oligopeptide transport system 1) was highest at 4h, while gene expression of Opp2 increased over time reaching its highest level at 12h, suggesting that the two systems have different specificities. Expression of a two-component regulatory system (2CRS), previously shown to regulate acid tolerance and proteolytic activity, also increased during the early log and early stationary phases of growth. Expression of the genes involved in lactose utilization increased immediately (5 min) upon exposure to milk. The acidification activity, survival under storage conditions, and adhesion to mucin and Caco-2 tissue culture cells of selected mutants containing insertionally inactivated genes differentially expressed in the wild-type strain during growth in milk were examined for any potential links between probiotic properties and bacterial growth and survival in milk. Some of the most interesting genes found to be expressed in milk were correlated with signaling (AI-2) and adherence to mucin and intestinal epithelial cells, in vitro.
2009-03-24 | GSE12924 | GEO
Project description:Metagenomic sequencing of probiotic supplements