Project description:We compared the microbiota of paired mouse caecal contents and faeces by applying a multi-omic approach, including 16S rDNA sequencing, shotgun metagenomics, and shotgun metaproteomics. The aim of the study was to verify whether faecal samples are a reliable proxy for the mouse colonic luminal microbiota, as well as to identify changes in taxonomy and functional activity between caecal and faecal microbial communities, which have to be carefully considered when using stool as sample for mouse gut microbiota investigations.
Project description:The human gut microbiota is crucial for degrading dietary fibres from the diet. However, some of these bacteria can also degrade host glycans, such as mucins, the main component of the protective gut mucus layer. Specific microbiota species and mucin degradation patterns are associated with inflammatory processes in the colon. Yet, it remains unclear how the utilization of mucin glycans affects the degradation of dietary fibres by the human microbiota. Here, we used three dietary fibres (apple pectin, β-glucan and xylan) to study in vitro the dynamics of colon mucin and dietary fibre degradation by the human faecal microbiota. The dietary fibres showed clearly distinguishing modulatory effects on faecal microbiota composition. The utilization of colon mucin in cultures led to alterations in microbiota composition and metabolites. Metaproteome analysis showed the central role of the Bacteroides in degradation of complex fibres while Akkermansia muciniphila was the main degrader of colonic mucin. This work demonstrates the intricacy of complex glycan metabolism by the gut microbiota and how the utilization of host glycans leads to alterations in the metabolism of dietary fibres. Metaproteomics analysis of this data reveals the functional activities of the bacteria in consortia, by this contributing to a better understanding of the complex metabolic pathways within the human microbiota that can be manipulated to maximise beneficial microbiota-host interactions.
Project description:The intestine is a site of diverse functions including digestion, nutrient absorption, immune surveillance, and microbial symbiosis. As such, intestinal homeostasis is vital for overall wellbeing. Faecal microRNAs (miRNAs) offer valuable non-invasive insights into the transcriptional state of the intestine. However, typical faecal miRNA yields and profiles remain incompletely characterised. Here, we develop an optimised protocol for faecal miRNA detection, and describe a reproducible murine faecal miRNA profile across several studies by performing a meta-analysis. By examining faecal miRNA changes during chronic infection with the gastrointestinal helminth, Trichuris muris, we identify the altered expression of miRNAs associated with fibrosis, barrier integrity and wound healing. Fibrosis was confirmed in vivo, suggesting a role for these miRNAs in regulating wound healing during chronic infection where the production of classical wound healing Th2 cytokines are low. Further implementations of this technique can identify novel hypotheses and therapeutic strategies in diverse disease contexts.
Project description:The incidence of type 2 diabetes (T2DM) induced by obesity is rapidly increasing. Although there are many drugs developed for type 2 diabetes, but the anti-diabetic effect of homology of medicine and food is also very popular with the majority of people. Burdock is one such food, but the molecular mechanism of anti-diabetic effect is unclear, limiting its further promotion. In recent years, studies have shown that plant mirnas can regulate host gene expression through dietary absorption, so plant miRNAs have become one of the main active ingredients in traditional Chinese medicine. Here, we report that miR8175, a plant miRNA from burdock root, has effective antidiabetic activity. miR8175 is highly enriched in burdock decoction. After administration of burdock decoction or synthetic miR8175 by gavage, significantly elevated levels of miR8175 in mouse serum and liver can be observed. Furthermore, both burdock decoction and miR8175 can significantly improve the impaired glucose metabolism of diabetic mice induced by a high-fat diet (HFD). Our results demonstrate that burdock decoction and miR8175 enhance the insulin sensitivity of the hepatic insulin signaling pathway by targeting PTPRF and PTP1B, which may be the reason for the improvement in metabolism.
Project description:The human gut microbiota is crucial for degrading dietary fibres from the diet. However, some of these bacteria can also degrade host glycans, such as mucins, the main component of the protective gut mucus layer. Specific microbiota species and mucin degradation patterns are associated with inflammatory processes in the colon. Yet, it remains unclear how the utilization of mucin glycans affects the degradation of dietary fibres by the human microbiota. Here, we used three dietary fibres (apple pectin, β-glucan and xylan) to study in vitro the dynamics of colon mucin and dietary fibre degradation by the human faecal microbiota. The dietary fibres showed clearly distinguishing modulatory effects on faecal microbiota composition. The utilization of colon mucin in cultures led to alterations in microbiota composition and metabolites. Metaproteome analysis showed the central role of the Bacteroides in degradation of complex fibres while Akkermansia muciniphila was the main degrader of colonic mucin. This work demonstrates the intricacy of complex glycan metabolism by the gut microbiota and how the utilization of host glycans leads to alterations in the metabolism of dietary fibres. Metaproteomics analysis of this data reveals the functional activities of the bacteria in consortia, by this contributing to a better understanding of the complex metabolic pathways within the human microbiota that can be manipulated to maximise beneficial microbiota-host interactions. In this study two different mucin samples were used: commercial porcine gastric mucin and in house prepared porcine colonic mucin. This dataset analyses the proteome of: A) autoclaved porcine colonic mucin; B) not autoclaved porcine colonic mucin; C) porcine gastric mucin.
Project description:Auricularia auricula is a well-known traditional edible and medicinal fungus with high nutritional and pharmacological values, as well as metabolic and immunoregulatory properties. However, the exact mechanisms underlying the effects of Auricularia auricula polysaccharides (AAP) on obesity and related metabolic endpoints, including the role of the gut microbiota, remain insufficiently understood. To determine the mechanistic role of the gut microbiota in observed anti-obesogenic effects AAP, faecal microbiota transplantation (FMT) and pseudo germ-free mice model treated with antibiotics were also applied, together with 16S rRNA genomic-derived taxonomic profiling. HFD murine exposure to AAP thwarted weight-gains, reduced fat depositing, together with upregulating thermogenesis proteomic biomarkers within adipose tissue. These effects were associated with diminished intestine/bloodstream-borne lipid transportation, together with enhanced glucose tolerance. FMT administered in tandem with antibiotic treatment demonstrated the intestinal microbiota was necessary in deploying AAP anti-obesogenic functions. Intestine-dwelling microbial population assessments discovered AAP to enhance (in a selective manner) Papillibacter cinnamivorans, a commensal bacterium having reduced presence within HFD mice. Notably, HFD mice treated with oral formulations of Papillibacter cinnamivorans diminished obesity and was linked to decreased intestinal lipid transportation. Datasets from the present study show that AAP thwarted dietary-driven obesity and metabolism-based disorders through regulating intestinal lipid transportation, a mechanism that is dependent on the gut commensal Papillibacter cinnamivorans. These results indicated AAP and Papillibacter cinnamivorans as newly identified pre- and probiotics that could possibly serve as novel countermeasure against obesity.
Project description:Auricularia auricula is a well-known traditional edible and medicinal fungus with high nutritional and pharmacological values, as well as metabolic and immunoregulatory properties. However, the exact mechanisms underlying the effects of Auricularia auricula polysaccharides (AAP) on obesity and related metabolic endpoints, including the role of the gut microbiota, remain insufficiently understood. To determine the mechanistic role of the gut microbiota in observed anti-obesogenic effects AAP, faecal microbiota transplantation (FMT) and pseudo germ-free mice model treated with antibiotics were also applied, together with 16S rRNA genomic-derived taxonomic profiling. HFD murine exposure to AAP thwarted weight-gains, reduced fat depositing, together with upregulating thermogenesis proteomic biomarkers within adipose tissue. These effects were associated with diminished intestine/bloodstream-borne lipid transportation, together with enhanced glucose tolerance. FMT administered in tandem with antibiotic treatment demonstrated the intestinal microbiota was necessary in deploying AAP anti-obesogenic functions. Intestine-dwelling microbial population assessments discovered AAP to enhance (in a selective manner) Papillibacter cinnamivorans, a commensal bacterium having reduced presence within HFD mice. Notably, HFD mice treated with oral formulations of Papillibacter cinnamivorans diminished obesity and was linked to decreased intestinal lipid transportation. Datasets from the present study show that AAP thwarted dietary-driven obesity and metabolism-based disorders through regulating intestinal lipid transportation, a mechanism that is dependent on the gut commensal Papillibacter cinnamivorans. These results indicated AAP and Papillibacter cinnamivorans as newly identified pre- and probiotics that could possibly serve as novel countermeasure against obesity.
Project description:Age-dependent changes of the gut-associated microbiome have been linked to increased frailty and systemic inflammation. This study found that age-associated changes of the gut microbiome of BALB/c and C57BL/6 mice could be reverted by co-housing of aged (22 months old) and adult (3 months old) mice for 30-40 days or faecal microbiota transplantation (FMT) from adult into aged mice. This was demonstrated using high-throughput sequencing of the V3-V4 hypervariable region of bacterial 16S rRNA gene isolated from faecal pellets collected from 3-4 months old adult and 22-23 months old aged mice before and after co-housing or FMT.