Project description:Within the human gut reside diverse microbes coexisting with the host in a mutually advantageous relationship. We comprehensively identified the modulatory effects of phylogenetically diverse human gut microbes on the murine intestinal transcriptome. Gene-expression profiles were generated from the whole-tissue intestinal RNA of mice colonized with various single microbial strains. The selection of microbe-specific effects, from the transcriptional response, yielded only a small number of transcripts, indicating that symbiotic microbes have only limited effects on the gut transcriptome overall. Moreover, none of these microbe-specific transcripts was uniformly induced by all microbes. Interestingly, these responsive transcripts were induced by some microbes but repressed by others, suggesting different microbes can have diametrically opposed consequences.
Project description:We report the application of bulk RNA-sequencing-based technology for high-throughput profiling to examine the individual and combinatorial effects of the liver circadian clock and gut microbes on the liver transcriptome over 24-hours. Principle Component Analysis demonstrated that functionality of the liver circadian clock is the primary driver of the hepatic transcriptome profile, and presence of microbes is the secondary driver. We identified a range of significantly oscillating transcripts within each experimental group using empirical_JTK_CYCLE, and revealed an overall increase in oscillating transcripts with both the loss of cuntional liver clock and gut microbes. Network analysis via Spearman correlation revealed that a broken liver clock results in increased connections and correlated transcripts only in the presence of gut microbes. Finally, we show by differential expression and gene set enrichment analysis that several key metabolic pathways, particularly carbohydrate and lipid metabolism, were significantly downregulated when the liver clock is broken, regardless of microbial status. This study demonstrates the complex contributions of the liver circadian clock and gut microbes in transcriptome programming, both over time and overall.
Project description:Coronary artery disease (CAD) is a widespread heart condition caused by atherosclerosis and influences millions of people worldwide. Early detection of CAD is challenging due to the lack of specific biomarkers. The gut microbiota and host-microbiota interactions have been well documented to affect human health. However, investigation that reveals the role of gut microbes in CAD is still limited. This study aims to uncover the synergistic effects of host genes and gut microbes associated with CAD through integrative genomic analyses.
Project description:Coronary artery disease (CAD) is a widespread heart condition caused by atherosclerosis and influences millions of people worldwide. Early detection of CAD is challenging due to the lack of specific biomarkers. The gut microbiota and host-microbiota interactions have been well documented to affect human health. However, investigation that reveals the role of gut microbes in CAD is still limited. This study aims to uncover the synergistic effects of host genes and gut microbes associated with CAD through integrative genomic analyses.
Project description:au07-05_groundworms - groundworms - Do earthworms affect plant growth through signal molecules? - Plants were grown in a sandy soil from the Centre de Recherche en Ecologie Expérimentale et Prédictive (CEREEP, France), in the presence or absence of earthworms. Soil was dried and sieved at 2 mm before to be put in the pots. There was 2 levels of treatment (presence or absence of earthworms in the soil), and 5 plants per treatments. Keywords: treated vs untreated comparison
Project description:Opioids such as morphine have many beneficial properties as analgesics, however, opioids may induce multiple adverse gastrointestinal symptoms. We have recently demonstrated that morphine treatment results in significant disruption in gut barrier function leading to increased translocation of gut commensal bacteria. However, it is unclear how opioids modulate the gut homeostasis. By using a mouse model of morphine treatment, we studied effects of morphine treatment on gut microbiome. We characterized phylogenetic profiles of gut microbes, and found a significant shift in the gut microbiome and increase of pathogenic bacteria following morphine treatment when compared to placebo. In the present study, wild type mice (C57BL/6J) were implanted with placebo, morphine pellets subcutaneously. Fecal matter were taken for bacterial 16s rDNA sequencing analysis at day 3 post treatment. A scatter plot based on an unweighted UniFrac distance matrics obtained from the sequences at OTU level with 97% similarity showed a distinct clustering of the community composition between the morphine and placebo treated groups. By using the chao1 index to evaluate alpha diversity (that is diversity within a group) and using unweighted UniFrac distance to evaluate beta diversity (that is diversity between groups, comparing microbial community based on compositional structures), we found that morphine treatment results in a significant decrease in alpha diversity and shift in fecal microbiome at day 3 post treatment compared to placebo treatment. Taxonomical analysis showed that morphine treatment results in a significant increase of potential pathogenic bacteria. Our study shed light on effects of morphine on the gut microbiome, and its role in the gut homeostasis.
Project description:Innate immune responses contributed to the containment of intestinal microbes. We used microarrays to examine transcriptional profiles of imflamed guts raised in convential or germ-free conditions. We found that gut inflammation and the gut microbiome regulate the expression of several hundred host genes.
Project description:Aging is associated with declining immunity and inflammation as well as alterations in the gut microbiome with a decrease of beneficial microbes and increase in pathogenic ones. The aim of this study was to investigate aging associated gut microbiome in relation to immunologic and metabolic profile in a non-human primate (NHP) model. 12 old (age>18 years) and 4 young (age 3-6 years) Rhesus macaques were included in this study. Immune cell subsets were characterized in PBMC by flow cytometry and plasma cytokines levels were determined by bead based multiplex cytokine analysis. Stool samples were collected by ileal loop and investigated for microbiome analysis by shotgun metagenomics. Serum, gut microbial lysate and microbe-free fecal extract were subjected to metabolomic analysis by mass-spectrometry. Our results showed that the old animals exhibited higher inflammatory biomarkers in plasma and lower CD4 T cells with altered distribution of naïve and memory T cell maturation subsets. The gut microbiome in old animals had higher abundance of Archaeal and Proteobacterial species and lower Firmicutes than the young. Significant enrichment of metabolites that contribute to inflammatory and cytotoxic pathways was observed in serum and feces of old animals compared to the young. We conclude that aging NHP undergo immunosenescence and age associated alterations in the gut microbiome that has a distinct metabolic profile.
Project description:Intestinal microbiota dysbiosis is related to many metabolic diseases in human health. Meanwhile, as an irregular environmental light-dark cycle, short-day (SD) may induce host circadian rhythms disturbances and worsen the risks of gut dysbiosis. Herein, we investigated how LD cycles regulate intestinal metabolism upon the destruction of gut microbes with antibiotic treatments. The transcriptome data indicated that SD have some negative effects on hepatic metabolism, endocrine, digestive, and diseases processes compared with normal light-dark cycle (NLD).The SD induced epithelial and hepatic purine metabolism pathway imbalance in ABX mice, the gut microbes, and their metabolites, all of which could contribute to host metabolism and digestion, endocrine system disorders, and may even cause diseases in the host.
Project description:The liver circadian clock is reprogrammed by nutritional challenge through the rewiring of specific transcriptional pathways. As the gut microbiota is tightly connected to host metabolism, whose coordination is governed by the circadian clock, we explored whether gut microbes influence circadian homeostasis and how they distally control the peripheral clock in the liver. Using fecal transplant procedures we reveal that, in response to high fat diet, the gut microbiota drives PPARγ-mediated activation of newly oscillatory transcriptional programs in the liver. Moreover, antibiotics treatment prevents PPARγ-driven transcription in the liver, underscoring the essential role of gut microbes in clock reprogramming and hepatic circadian homeostasis. Thus, a specific molecular signature characterizes the influence of the gut microbiome in the liver, leading to the transcriptional rewiring of hepatic metabolism. We used microarray to quantify the tissue specific expression level of circadian genes in terms of total RNA.