Project description:beta-glucan induced glycolysis in HIF-1 depedent manner. We reported that beta-glucan injection in mice led to upregulated glycolysis. HIF-1a plays a major role in this process. Mice receives beta-glucan via ip for 4 days. Splenocytes were isolated for RNA sequencing.
Project description:We found that beta-glucan treatment induces early induction of transcripts associated with inflammation and metabolism. Several days after beta-glucan treatment, genes associated with differentation and housekeeping remain upregulated. LPS treatment induces a strong inflammatory response. Beta-glucan did not significantly alter the macrophage response to LPS.
Project description:beta-glucan induced glycolysis in HIF-1 depedent manner. We reported that beta-glucan injection in mice led to upregulated glycolysis. HIF-1a plays a major role in this process.
Project description:We established a bacteria infective intestinal inflammation in turbot (Scophthalmus maximus). And found that β-glucan could significantly alleviate the phenotype of turbot intestinal inflammation. We performed single cell transcriptome analysis to study bacteria infective intestinal inflammation and the effects of β-glucan. Furthermore, we revealed that β-glucan through activates Th17 cells to alleviate intestinal inflammation in turbot.
Project description:Background & Aims: Non-alcoholic fatty liver disease (NALFLD)-associated changes in gut microbiota are important drivers of disease progression toward fibrosis. Therefore, reversing microbiota alterations could ameliorate NAFLD progression. Oat beta-glucan, a non-digestible polysaccharides, has shown promising therapeutic effects on hyperlipidemia associated with NAFLD, but its impact on gut microbiota and most importantly NAFLD fibrosis remains unknown. Methods: We performed detailed metabolic phenotyping including body composition, glucose tolerance, and lipid metabolism as well as comprehensive characterization of the gut-liver axis in a western-style diet (WSD)-induced model of NAFLD and assessed the effect of a beta-glucan intervention on early and advanced liver disease. Gut microbiota was modulated using broad-spectrum antibiotic (Abx) treatment. Results: Oat beta-glucan supplementation did not affect WSD-induced body weight gain, glucose intolerance, and the metabolic phenotype remained largely unaffected. Interestingly, oat beta-glucan dampened NAFLD inflammation, associated with significantly reduced monocyte-derived macrophages (MoMFs) infiltration, fibroinflammatory gene expression, and strongly reduced fibrosis development. Mechanistically, this protective effect was not mediated by changes in bile acid composition or signaling, but was dependent on gut microbiota and was lost upon Abx treatment. Specifically, oat beta-glucan partially reversed unfavorable changes in gut microbiota, resulting in an expansion of protective taxa, including Ruminococcus, and Lactobacillus followed by reduced translocation of TLR ligands. Conclusions: Our findings identify oat beta-glucan as a highly efficacious food supplement that dampens inflammation and fibrosis development in diet-induced NAFLD. These results, along with its favorable dietary profile, suggest that it may be a cost-effective and well-tolerated approach to preventing NAFLD progression and should be assessed in clinical studies.
Project description:A clone encoding carboxymethylcellulase activity was isolated during functional screening of a human gut metagenomic library using Lactococcus lactis MG1363 as heterologous host. The insert sequence revealed a glycoside hydrolase family 9 (GH9) catalytic domain with sequence similarity to a gene from Coprococcus sp. ART55/1, which is closely related to Coprocococcus eutactus. Surveys of available genomes indicated a limited distribution of GH9 domains among dominant human colonic anaerobes. Genomes of two Coprococcus-related strains showed the presence of two GH9-encoding and four GH5-encoding genes, however, the strains did not appear to be able to degrade cellulose. Instead, they grew well on beta-glucans and one of the strains also showed growth on galactomannan, galactan and glucomannan. Gene expression and proteomic analysis of Coprococcus sp. ART55/1 grown on cellobiose, beta-glucan and lichenan led to a similar change in expression in comparison to glucose. On beta-glucan and lichenan only, one of the four GH5 genes was strongly upregulated. Growth on glucomannan lead to a transcriptional response of many genes, in particular a strong upregulation of glycoside hydrolases involved in mannan degradation. Thus, beta-glucans are a major growth substrate for species related to Coprococcus eutactus, with glucomannan and galactans alternative substrates for some strains.
Project description:Acanthamoeba castellanii (Ac) and macrophages share structural, morphological, physiological and biochemical similarities, including the ability to phagocyte a myriad of microorganisms in the environments they live. Whereas there is voluminous information on phagocytic receptors of macrophages, for Ac, the understanding of how the recognition of extracellular microorganisms works still awaits elucidation. Recently, our group described mannose-binding proteins expressed on the surface of the trophozoites. However, as soluble mannose did not inhibit entirely the process, other interactions might be possible. In the present work, we aimed to characterize the potential Ac proteins able to recognize the polysaccharide β-1,3-glucan on fungal surfaces. Our data demonstrate that Ac could bind curdlan or laminarin on its surface as detected by Dectin-1-Fc and fluorescent conjugate, suggesting the presence of β-1,3-glucan binding molecules. Optical tweezers detected higher adhesion affinity of laminarin or curdlan coated beads to A. castellanii (characteristic time of 46.9 s and 43.9 s, respectively) in comparison control beads (BSA or dextran-coated). In agreement, a H. capsulatum (Hc) G217B having β-1,3-glucan as the most external layer strongly adhered to Ac (characteristic time of 5.3 s), whereas Hc G186A, an α-1,3-glucan expressing strain, displayed much lower adhesion forces (characteristic time of 83.6 s). The specificity of our system was confirmed with addition of soluble β-1,3-glucan, which inhibited dramatically the adhesion of Hc G217B to Ac (characteristic time of 38,5 s). By indirect ELISA, the biotinylated extract of Ac showed higher binding to Hc G217B surface than Hc G186A, as similar results were observed when using Dectin-1-Fc. By interaction assays, association rates to Ac and RAW macrophages were twice higher for Hc G217B when compared to Hc G186A. Inhibitions with mannose, or its combinations with curdlan or laminarin demonstrated inhibitions higher than 50% during Ac and Hc G217B interaction. For RAW macrophages, the combinations mannose + laminarin and mannose + curdlan had inhibition of 64.4% and 51.5%, respectively, in the interaction with Hc G217B. The killing assay show that for A. castellanii, there was a decrease in the number of viable fungi when either laminarin and curdlan were added, which is similar to results observed with macrophages, suggesting the participation of this receptor for fungal entrance and survival within phagocytes. Proteomics identified several proteins with the capacity to bind β-1,3-glucans, including a membrane integral component (L8HDD6) displaying a legume lectin domain and also belonging to the Concanavalin A-like lectin/glucanase domain superfamily. By the demonstrated binding specificity of this receptor, our data reinforce other pathways of fungal recognition and suggests to a possible parallel or even divergent evolution, between A. castellanii and macrophages.