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:Resistant starches (RS) are dietary compounds processed by the gut microbiota into metabolites, such as butyrate, that are beneficial to the host. The production of butyrate by the microbiome appears to be affected by the plant source and type of RS as well as the individual's microbiota. In this study, we used in vitro culture and metaproteomic methods to explore individual microbiome's functional responses to RS2 (enzymatically-resistant starch), RS3 (retrograded starch) and RS4 (chemically-modified starch). Results showed that RS2 and RS3 significantly altered the protein expressions in the individual gut microbiomes, while RS4 did not result in significant protein changes. Significantly elevated protein groups were enriched in carbohydrate metabolism and transport functions of families Eubacteriaceae, Lachnospiraceae and Ruminococcaceae. In addition, Bifidobacteriaceae was significantly increased in response to RS3. We also observed taxon-specific enrichments of starch metabolism and pentose phosphate pathways corresponding to this family. Functions related to starch utilization, ABC transporters and pyruvate metabolism pathways were consistently increased in the individual microbiomes in response to RS2 and RS3. Given that these taxon-specific responses depended on the type of carbohydrate sources, we constructed a functional ecological network to gain a system-level insight of functional organization. Our results suggest that while some microbes tend to be functionally independent, there are subsets of microbes that are functionally co-regulated by environmental changes, potentially by alterations of trophic interactions.
Project description:We have previously demonstrated that the gut microbiota can play a role in the pathogenesis of conditions associated with exposure to environmental pollutants. It is well accepted that diets high in fermentable fibers such as inulin can beneficially modulate the gut microbiota and lessen the severity of pro-inflammatory diseases. Therefore, we aimed to test the hypothesis that hyperlipidemic mice fed a diet enriched with inulin would be protected from the pro-inflammatory toxic effects of PCB 126.
Project description:Aims Gut microbiota-mediated inflammation promotes obesity-associated low-grade inflammation, which represents a hallmark of the metabolic syndrome (MetS). Lifestyle-induced weight loss (WL) is regarded as an efficient therapy to reverse MetS and to prevent disease progression. The objective of this study was to investigate if lifestyle-induced WL modulates the gut microbiome and its interaction with the host. Methods We analyzed and compared the fecal metaproteome of 33 individuals with MetS in a longitudinal study before and after lifestyle-induced WL in a well-defined cohort (ICTRP Trial Number: U1111-1158-3672). Results The 6-month WL intervention resulted in reduced BMI (-13.9%), increased insulin sensitivity (HOMA-IR; -53.70%) and reduced levels of circulating CRP (-66.86%), indicating MetS reversal. The metaprotein spectra of the host revealed a decrease of human proteins associated with gut inflammation and reduced abundance of human pancreatic alpha-amylase. Surprisingly, taxonomic analysis of the fecal metaproteome revealed only minor changes in the bacterial composition with an increase of low-abundant families (Desulfovibrionaceae, Leptospiraceae, Syntrophomonadaceae, Thermotogaceae, Verrucomicrobiaceae). Yet, we detected increased abundance of microbial metaprotein spectra that correspond to enhanced hydrolysis of complex carbohydrates (endoglucanase A, β-1,4-mannooligosaccharide phosphorylase, galactokinase, 5-keto-D-gluconate 5-reductase), indicating functional changes of the gut microbiome. Conclusions Our results indicate that lifestyle induced WL may improve interaction between the gut microbiome and the host in individuals with MetS, while bacterial composition remained almost stable. Metaproteome analysis of host proteins reveals reduced gut inflammation whereas microbial metaprotein spectra indicate functional changes towards degradation of complex carbohydrates. The filenames correspond to the ID of the patient (1-33), whereas “C” corresponds to baseline and “ABC” to weight loss.
Project description:Stool samples were collected from 4 children and subjected to deep gut metaproteomics analysis for in-depth understanding the functional compositions of human gut mcirobiome.
Project description:RNA was extracted from the meninges of mice from either Specific pathogen free or Germ free facilities or from the offspring of mice reconstituted with different human microbiomes.