Project description:In this paper, we have employed transcriptomic analysis as a pivotal tool to dissect the molecular landscape across the quintet of growth and developmental phases exhibited by Oudemansiella raphanipes. Our investigation has not only unveiled a suite of critical differentially expressed genes but also shed light on the nuanced nutritional attributes intrinsic to this fungal species. These findings promise to furnish fresh insights, serving as a beacon for the enhanced comprehension of O. raphanipes biology.
Project description:Obesity is associated with an increased risk of mucosal infections; however, the mechanistic basis of this phenomenon remains incompletely defined. Intestinal mucus barrier systems normally prevent infections, but are sensitive to changes in the luminal environment. Here we demonstrate that mice exposed to an obesogenic Western-style diet (WSD) suffer regiospecific failure of the mucus barrier in the small intestinal jejunum caused by diet-induced mucus condensation, which occurs independently of microbiota alterations. Mucus barrier disruption due to either WSD exposure or chromosomal Muc2 deletion results in collapse of the commensal jejunal microbiota, which in turn sensitises mice to atypical jejunal colonization by the enteric pathogen Citrobacter rodentium. We identify the jejunal mucus layer as a microbial habitat, and link the regiospecific mucus dependency of the microbiota to fundamental properties of the jejunal niche. Together, our data identifies a symbiotic mucus-microbiota relationship that normally prevents jejunal pathogen colonization, but is highly sensitive to disruption by exposure to a Western-style diet.
Project description:On the basis of the clear role of Astraglus polysaccharides (APS) in the prevention of obesity and non-alcoholic fatty liver (NAFLD) induced by high-fat diet, the potential effector genes of APS are screened by means of transcriptional techniques.
2021-04-13 | GSE113263 | GEO
Project description:Effects of polysaccharides from Platycodon grandiflorus on diet-induced obesity
Project description:Germfree (GF) mice have been used as a model to study the contribution of the intestinal microbiota to metabolic energy balance of the host. Despite a wealth of knowledge accumulated since the 1940’s, the response of GF mice to a high fat diet is largely unknown. In the present study, we compared the metabolic consequences of a high fat (HF) diet on GF and conventional (Conv) C57BL/6J mice. As expected, Conv mice developed obesity and glucose intolerance with a HF diet. In contrast, GF mice remained lean and resisted the HF diet-induced insulin resistance. The anti-obesity phenotype of GF/HF mice was accompanied by reduced caloric intake, diminished food efficiency, and excessive fecal lipid excretion contributed to the reduced food efficiency. In addition, HF diet-induced hypercholesterolemia was ameliorated, which was partially due to an increase in fecal cholesterol excretion. However, hepatic cholesterols were increased in GF/HF mice. Elevated nuclear SREBP2 proteins and the up-regulation of cholesterol biosynthesis genes support the increased liver cholesterol biosynthesis in GF/HF mice. The resistance to HF diet-induced metabolic abnormalities in GF mice was also associated with a reduced immune response, indicated by low plasma pro-inflammatory and anti-inflammatory markers. These data suggest that the gut microbiota of Conv mice contributes to HF diet-induced obesity, insulin resistance, dyslipidemia and hepatic steatosis in mice. Thus, results of the present study describe the metabolic responses of GF mice to a HF diet and further our understandings of the relationship between the gut microbiota and the host. Germfree and conventional C57BL/6J mice were fed with a high fat diet for 11 weeks. Then, all mice were sacrified under 10-h food deprevation, and liver samples of germfree (n=14) and conventional (n=16) were examined.
Project description:This dataset contains proteomic data from mice with high or low weight gain in response to a high fat diet. Both host and microbial proteins are present. In the supplemental, there are also tables and supplementary files that can be used for replicating the bioinformatic analysis.
Abstract:
Consumption of refined high-fat, low-fiber diets promotes development of obesity and its associated consequences. While genetics play an important role in dictating susceptibility to such obesogenic diets, mice with nearly uniform genetics exhibit marked heterogeneity in their extent of obesity in response to such diets. This suggests non-genetic determinants play a role in diet-induced obesity. Hence, we sought to identify parameters that predict, and/or correlate with, development of obesity in response to an obesogenic diet. We assayed behavior, metabolic parameters, inflammatory markers/cytokines, microbiota composition, and the fecal metaproteome, in a cohort of mice (n=50) prior to, and the 8 weeks following, administration of an obesogenic high-fat low-fiber diet. Neither behavioral testing nor quantitation of inflammatory markers broadly predicted severity of diet-induced obesity. Although, the small subset of mice that exhibited basal elevations in serum IL-6 (n=5) were among the more obese mice in the cohort. While fecal microbiota composition changed markedly in response to the obesogenic diet, it lacked the ability to predict which mice were relative prone or resistant to obesity. In contrast, fecal metaproteome analysis revealed functional and taxonomic differences among the proteins associated with proneness to obesity. Targeted interrogation of microbiota composition data successfully validated the taxonomic differences seen in the metaproteome. While future work will be needed to determine the breadth of applicability of these associations to other cohorts of animals and humans, this study nonetheless highlights the potential power of gut microbial proteins to predict and perhaps impact development of obesity.
Project description:Obesity is an independent risk factor for colorectal cancer (CRC) although the underlying mechanisms have not been elucidated. Dietary nutrients play a key role in both the prevention and promotion of CRC. While iron is an essential nutrient, excess iron is associated with carcinogenesis. Unlike the systemic compartment, the intestinal lumen lacks an efficient system to regulate iron. In conditions when dietary iron malabsorption and intestinal inflammation co-exist, greater luminal iron is associated with increased intestinal inflammation and a shift in the gut microbiota to more pro-inflammatory strains. However, treatments designed to reduce luminal, including diet restriction and chelation, are associated with lower intestinal inflammation and the colonization of protective gut microbes. Obesity is associated with inflammation-induced, hepcidin-mediated, iron metabolism dysfunction characterized by iron deficiency and dietary iron malabsorption. Obesity is also linked to intestinal inflammation. Currently, there is a fundamental gap in understanding how altered iron metabolism impacts CRC risk in obesity.
The investigator’s objective is to conduct a crossover controlled feeding trial of: 1) a "Typical American" diet with "high" heme/non-heme iron", 2) a "Typical American" diet with "low" iron, and 3) a Mediterranean diet with "high" non heme iron and examine effects on colonic and systemic inflammation and the gut microbiome.