Project description:The gut microbiota impacts many aspects of host biology including immune function. One hypothesis is that microbial communities induce epigenetic changes with accompanying alterations in chromatin accessibility, providing a mechanism that allows a community to have sustained host effects even in the face of its structural or functional variation. We used ATAC-seq to define chromatin accessibility in predicted enhancer regions of intestinal αβ+ and γδ+ intraepithelial lymphocytes (IELs) purified from germ-free mice, their conventionally-raised (CONV-R) counterparts, and mice reared GF and then colonized with a CONV-R gut microbiota at the end of the suckling-weaning transition. Characterizing genes adjacent to traditional enhancers and super-enhancers revealed signaling networks, metabolic pathways, and enhancer-associated transcription factors affected by the microbiota. Our results support the notion that epigenetic modifications help define microbial community-affiliated functional features of host immune cell lineages.
2016-11-28 | GSE89646 | GEO
Project description:Adipokines influence on suckling rat GALT and microbiota
Project description:This study in rats was designed to investigate whether whole rhye (WR) can influence the metabolism of n-3 and n-6 long-chain fatty acids (LCFA) and gut microbiota composition. For 12 weeks, rats were fed a diet containing either 50% WR or 50% refined rye (RR). Total bacterial DNA was extracted from fecal and cecal samples (n=5 per group). 16S PCR amplification was performed to assess the microbial diversity at the family level using the HuGChip. Amplified DNA was purified and labelled with either Cy3 or Cy5 dye and hybridized on the microarray.
Project description:This study in rats was designed to investigate whether whole rhye (WR) can influence the metabolism of n-3 and n-6 long-chain fatty acids (LCFA) and gut microbiota composition. For 12 weeks, rats were fed a diet containing either 50% WR or 50% refined rye (RR). Total bacterial DNA was extracted from fecal and cecal samples (n=5 per group). 16S PCR amplification was performed to assess the microbial diversity at the family level using the HuGChip. Amplified DNA was purified and labelled with either Cy3 or Cy5 dye and hybridized on the microarray. A 15 chip study was realized, each corresponding to hybridization with 250ng of labelled 16S rRNA gene amplicons from either mice fecal and cecal samples. Each probe (4441) was synthetized in three replicates.
Project description:High protein diet alter gut microbiota composition and activity. The objective of this study is to determine the consequences of a high protein diet for the colonic epithelium in rats.
Project description:Chronic acid suppression by proton pump inhibitor (PPI) has been hypothesized to alter the gut microbiota via a change in intestinal pH. To evaluate the changes in gut microbiota composition by long-term PPI treatment. Twenty-four week old F344 rats were fed with (n = 5) or without (n = 6) lansoprazole (PPI) for 50 weeks. Then, profiles of luminal microbiota in the terminal ileum were analyzed. Pyrosequencing for 16S rRNA gene was performed by genome sequencer FLX (454 Life Sciences/Roche) and analyzed by metagenomic bioinformatics.
Project description:This study aims to identify genome-wide placental DNA differential methylation positions (DMPs) in fetal overgrowth and the associations with fetal growth factors, leptin and adiponectin. In the Shanghai Birth Cohort, we studied 30 pairs of placentals of large-for-gestational-age (LGA, birth weight>90th percentile, an indicator of fetal overgrowth) and optimal-for-gestational-age (OGA, 25th-75th percentiles, control) newborns matched by sex and gestational age. Placental DNA methylations were measured by the Illumina Infinium Human Methylation-EPIC BeadChip. Cord blood insulin, C-peptide, proinsulin, IGF-1, IGF-2, leptin and adiponectin concentrations were measured. We identified 543 DMPs (397 hypermethylated, 146 hypomethylated) comparing LGA vs. OGA at false discovery rate <5% and absolute methylation difference >0.05 adjusting for placental cell type heterogeneity, maternal age, pre-pregnancy BMI and HbA1c levels during pregnancy. We validated a hyper-methylated gene - cadherin 13 (CDH13) reported in a previous epigenome-wide association study, and validated a newly discovered differentially (hyper-)methylated gene -visual system homeobox 1 (VSX1) in an independent pyrosequencing study sample (47 LGA-control pairs). Pathway analysis did not detect any statistically significant pathway correcting for multiple tests. Adiponectin in cord blood was correlated with its gene methylation in the placenta, while other observed biomarkers were not. Fetal overgrowth was associated with a large number of altered placental gene DNA methylations. The study provides robust evidence suggesting that placental CDH13 and VSX1 genes are hyper-methylated in LGA. Placental gene methylation was correlated with cord blood biomarker for adiponectin, but not for leptin and fetal growth factors.
Project description:Obesity is a leading cause of primary hypertension in children, and a high-fat intake and the gut microbiota may be involved in the pathogenesis of obesity-related hypertension (OrHTN), but the underlying mechanisms are not fully understood. Here, we show that high-fat diet (HFD) feeding alters the gut microbiota composition in OrHTN rats, resulting in a reduced abundance of the butyrate-producing bacteria Ruminococcus and a subsequent decrease in plasma butyrate levels. Histone 3 lysine 9 butyrylation (H3K9bu) levels decreased in the kidneys of OrHTN rats, which downregulates the expression of the hypertension-related MAS1 gene. Furthermore, sodium butyrate affected H3K9bu modification levels in a concentration-dependent manner, with decreased H3K9bu and downregulated MAS1 expression at low concentrations in human proximal tubular epithelial cells. Our results suggest that a HFD contributes to the development of OrHTN by altering the gut microbiota and its metabolites, leading to the downregulation of H3K9bu and hypertension-related gene expression.
Project description:Emerging knowledge shows the importance of early life events in programming the intestinal mucosal immune system and development of the intestinal barrier function. These processes depend heavily on close interactions between gut microbiota and host cells in the intestinal mucosa. In turn, development of the intestinal microbiota is largely dependent on available nutrients and substrates required for the specific microbial community structures to expand. It is currently not known what the specificities are of intestinal microbial community structures in relation to the programming of the intestinal mucosal immune system and development of the intestinal barrier function. The objective of the present study was to investigate the effect of a nutritional intervention on intestinal development of suckling piglets by daily oral administration of fructooligosaccharides (FOS) over a period of 12 days. At the microbiota community level a clear “bifidogenic” effect of the FOS administration was observed in colon digesta at day 14. The former, however, did not translate into significant changes of local gene expression in the colonic mucosa. In the jejunum, significant changes were observed for microbiota composition at day 14, and microbiota diversity at day 25. In addition, significant differentially expressed gene sets in mucosal tissues of jejunum were identified at both days 14 and 25 of age. At the age of 14 days, lower activity of cell cycle-related processes and a higher activity of extracellular matrix processes were observed in jejunal scrapings of piglets supplemented with FOS compared to control piglets. At day 25, lower activity of immune-related processes in jejunal tissue were seen in piglets supplemented with FOS. Histological parameters, villi height and crypt depth, were significantly different at day 25 between the experimental and control group, where piglets supplemented with FOS had higher villi and deeper crypts. We conclude that oral FOS administration during the suckling period of piglets has significant bifidogenic effects on the microbiota in the colon and on gene expression in jejunal mucosa scrapings. We hypothesize that FOS supplementation of suckling piglets results in a higher butyrate production in the colon due to the increase in bifidobacteria and lactobacilli in the hindgut. We further speculate that a higher butyrate production in colonic digesta relates to changes in gene expression in the jejunum by thus far unknown mechanisms.