Similar Datasets
Project description:Declining FXR expression coordinates neonatal beta cell mass development with microbial bile acid metabolism maturation in mice
| PRJNA1008083 | ENA
Project description:Weaning diet switch brings gut microbiome maturation along with postnatal formation of sufficient matured β-cell mass. The matured gut microbiota elevated agonistic components of bile acid (BA) pool towards farnesoid X receptor (FXR) that was paralleling with the declined β-cell FXR expression. To investigate whether BA/FXR could link postnatal β-cell development and gut microbiota maturation, we forced persistent FXR expression in β cells (βFxrKI) and found decreased neonatal β-cell mass growth and increased glycemia in weaned βFxrKI mice, which could be partially recovered by ablating gut microbiota before weaning. scRNA and scATAC seq analysis showed different β cell growth trajectories with suppressed intrinsic cell proliferation and elevated cell apoptosis in βFxrKI. Caspase-6 was then identified as a dominant β-cell FXR downstream effector to mediate its regulation. The negative regulation of the FXR-Casp6 axis on postnatal β-cell mass expansion reflected a programmed cellular response to gut microbiota maturation in neonatal mice.
2025-11-13 | GSE241407 | GEO
Project description:Weaning diet switch brings gut microbiome maturation along with postnatal formation of sufficient matured β-cell mass. The matured gut microbiota elevated agonistic components of bile acid (BA) pool towards farnesoid X receptor (FXR) that was paralleling with the declined β-cell FXR expression. To investigate whether BA/FXR could link postnatal β-cell development and gut microbiota maturation, we forced persistent FXR expression in β cells (βFxrKI) and found decreased neonatal β-cell mass growth and increased glycemia in weaned βFxrKI mice, which could be partially recovered by ablating gut microbiota before weaning. scRNA and scATAC seq analysis showed different β cell growth trajectories with suppressed intrinsic cell proliferation and elevated cell apoptosis in βFxrKI. Caspase-6 was then identified as a dominant β-cell FXR downstream effector to mediate its regulation. The negative regulation of the FXR-Casp6 axis on postnatal β-cell mass expansion reflected a programmed cellular response to gut microbiota maturation in neonatal mice.
2025-11-13 | GSE241406 | GEO
Project description:Studies demonstrate a role for neurotensin (NT) in obesity and related comorbidities. Bile acid (BA) homeostasis alterations are associated with obesity. We determined the effect of NT on BA metabolism in obese and non-obese conditions. Plasma and fecal BA profiles were analyzed by LC-MS/MS in male and female NT+/+ and NT-/- mice fed low-fat (LFD) or high-fat diet (HFD) for 6 weeks (early stage of obesity) or greater than 20 weeks (late stage of obesity). The nuclear farnesoid X receptor (FXR) and BA transporter mRNA expression were assessed in ileum, mouse enteroids, and human cell lines. HFD decreased plasma primary and secondary BAs in NT+/+ mice; HFD-induced decrease of plasma BAs was improved in NT-deficient mice. In NT+/+ mice, HFD inhibited ileal FXR and BA transporter expression; HFD-decreased expression of FXR and BA transporters was prevented in NT-/- mice. Compared with LFD-fed NT+/+ mice, LFD-fed NT-/- mice had relatively lower levels of ileal FXR and BA transporter expression. Moreover, NT stimulates the expression of FXR and BA transporters in Caco-2 cells; however, stimulated expression of BA transporters was attenuated in NT-/- enteroids. Therefore, we demonstrate that HFD disrupts the BA metabolism and ileal FXR and BA transporter axis which are improved in the absence of NT, suggesting that NT contributes to HFD-induced disruption of BA metabolism and plays an inhibitory role in the regulation of ileal FXR and BA transporter signaling under obese conditions. Conversely, NT positively regulates the expression of ileal FXR and BA transporters under non-obese conditions. Therefore, NT plays a dual role in obese and non-obese conditions, suggesting possible therapeutic strategies for obesity control.
| S-EPMC9134645 | biostudies-literature
Project description:The purpose of this study was to elucidate potential effects of fxr mutation on the functional specification of intestinal epithelial cells. To do this, we sorted GFP-positive cells from TgBAC(cldn15la:GFP) transgenics of either fxr+/+ or fxr-/- fish larvae and subjected them to 10X Genomics single-cell RNA-seq. Our results uncovered the requirement of fxr in gene expression and differentiation among multiple intestinal epithelial cell types.
2021-04-30 | GSE173570 | GEO
Project description:Neonatal cholestasis disease (NCD) is a complex and easily mis-diagnosed condition. We analyzed microbiota community structure in feces and measured short-chain fatty acids, bile acids (BAs) and liver function of 12 healthy, 13 NCD, and 13 treated infants after diagnosis. Based on 16S rRNA gene amplicon sequencing and gas-chromatographic-mass-spectrometric analysis of secondary BAs, we identified microbial genera and metabolites that associate with abnormal bile secretion. Streptococcus gallolyticus and Parabacteroides distasonis, and Lactobacillus gasseri had higher relative abundance in healthy and NCD infants respectively. Compared to NCD patients, healthy infants had higher LCA, CDCA and GCDCA fecal concentrations. The three microbial species and three secondary bile acids were selected as potential non-invasive combined biomarkers to diagnose NCD. We propose that microbiota-metabolite combined biomarkers could be used for diagnosis of NCD, and this may contribute to improved early clinical diagnosis of NCD in the future.
| S-EPMC7203226 | biostudies-literature
Project description:Bile acid (BA) production is a critical metabolic function of the liver, and its disruption leads to various liver diseases including hepatocellular carcinoma (HCC). However, the underlying molecular mechanism remained elusive. Here, we report that BA metabolism is directly controlled by a previously unidentified repressor function of YAP, a transcriptional activator known to promote HCC formation. We show in hepatocytes, activated YAP suppressed Fxr, a BA-sensing nuclear receptor that critically regulates BA production and export. The repressor function of activated YAP induced cholestasis damaged the liver, and altered liver and serum BA concentrations and composition. Specifically, YAP activation inhibited expression of an Fxr target gene, Bsep (Abcb11), impairing BA exportation and injuring hepatocytes. Elevated BA in the blood due to hepatocyte injury further activated hepatic YAP, resulting in a vicious cycle leading to HCC. In both mouse liver and human HCC patient samples, transcriptomic analysis negatively correlated YAP and Fxr activities. Mechanistically, Fxr was found to bind Teads in a DNA-binding-independent manner; and Teads recruited YAP to epigenetically reprogram Fxr by replacing the histone acetyltransferase, P300, with the histone deacetylase, HDAC1. Importantly, alleviating YAP repressor function in BA metabolism by activating Fxr with its agonist GW4064, inhibiting HDAC1 with Entinostat, or overexpressing Bsep, reduced cholestatic phenotypes including hepatic injury, fibrosis, and inflammation, alleviating the HCC caused by YAP activation. Our results identify Yap's transcriptional repressor role as a key driver of Yap-induced HCC and BA metabolism as a potential therapeutic target for HCC.
2025-02-10 | GSE272343 | GEO
Project description:The nuclear bile acid receptor farnesoid X receptor (FXR) is an important transcriptional regulator of bile acid, lipid, and glucose metabolism. FXR is highly expressed in the liver and intestine and controls the synthesis and enterohepatic circulation of bile acids. However, little is known about FXR-associated proteins that contribute to metabolic regulation. Here, we performed a mass spectrometry-based search for FXR-interacting proteins in human hepatoma cells and identified AMPK as a coregulator of FXR. FXR interacted with the nutrient-sensitive kinase AMPK in the cytoplasm of target cells and was phosphorylated in its hinge domain. In cultured human and murine hepatocytes and enterocytes, pharmacological activation of AMPK inhibited FXR transcriptional activity and prevented FXR coactivator recruitment to promoters of FXR-regulated genes. Furthermore, treatment with AMPK activators, including the antidiabetic biguanide metformin, inhibited FXR agonist induction of FXR target genes in mouse liver and intestine. In a mouse model of intrahepatic cholestasis, metformin treatment induced FXR phosphorylation, perturbed bile acid homeostasis, and worsened liver injury. Together, our data indicate that AMPK directly phosphorylates and regulates FXR transcriptional activity to precipitate liver injury under conditions favoring cholestasis.
| S-EPMC3938262 | biostudies-literature
Project description:Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality in premature infants with no specific treatments available. We aimed to identify the molecular mechanisms underlying NEC and investigate the therapeutic effects of Bacteroides fragilis on NEC. Clinical samples of infant feces, bile acid-targeted metabolomics, pathological staining, bioinformatics analysis, NEC rat model, and co-immunoprecipitation were used to explore the pathogenesis of NEC. Taxonomic characterization of the bile salt hydrolase (bsh) gene, enzyme activity assays, 16S rRNA sequencing, and organoids were used to explore the therapeutic effects of B. fragilis on NEC-related intestinal damage. Clinical samples, NEC rat models, and in vitro experiments revealed that total bile acid increased in the blood but decreased in feces. Moreover, the levels of FXR and other bile acid metabolism-related genes were abnormal, resulting in disordered bile acid metabolism in NEC. Taurochenodeoxycholic acid accelerated NEC pathogenesis and taurodeoxycholate alleviated NEC. B. fragilis displayed bsh genes and enzyme activity and alleviated intestinal damage by restoring gut microbiota dysbiosis and bile acid metabolism abnormalities by inhibiting the FXR-NLRP3 signaling pathway. Our results provide valuable insights into the therapeutic role of B. fragilis in NEC. Administering B. fragilis may substantially alleviate intestinal damage in NEC.
| S-EPMC11253882 | biostudies-literature
Project description:Objective: To explore the possible mechanisms of cholestasis induced by Polygoni Multiflori Radix (PM). Methods: Low and high doses of water extract of PM were given to mice by gavage for 8 weeks. The serum biochemical indexes of aspartate aminotransferase (AST), alanine aminotransferase (ALT), glutamyltransferase (GGT) alkaline phosphatase (ALP) and so on were detected in the second, fourth, sixth, and eighth weeks after administration. At the end of the eighth week of administration, the bile acid metabolic profiles of liver and bile were screened by high-performance liquid chromatography tandem triple quadrupole mass spectrometry (HPLC-QQQ-MS/MS). Liver pathological changes were observed by hematoxylin and eosin staining. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the mRNA transcription of the target genes and Western blotting (WB) was used to the detect target protein expression. Results: Biochemical tests results showed the values of ALP and GGT were two and three times greater than the normal values respectively, and the value of R was less than 2. Histopathology also showed that PM caused lymphocyte infiltration, a small amount of hepatocyte necrosis and nuclear fragmentation in mouse liver. The proliferation of bile duct epithelial cells was observed in the high group. These results indicated that PM may lead to cholestatic liver injury. HPLC-QQQ-MS/MS analysis with the multivariate statistical analysis revealed significant alterations of individual bile acids in liver and gallbladder as compared to those of the control group. RT-qPCR showed that the transcription of Fxr, Shp, Bsep, Bacs, Mdr2, and Ugt1a1 were downregulated and that of Cyp7a1, Mrp3, and Cyp3a11 was significantly upregulated in the treatment group. WB demonstrated that PM also markedly downregulated the protein expression of FXR, BSEP, and MDR2, and upregulated CYP7A1. Conclusion: PM inhibited the expression of FXR, which reduced the expression of MDR2 and BSEP, leading to the obstruction of bile acids outflow, and increased the expression of CYP7A1, resulting in an increase of intrahepatic bile acid synthesis, which can lead to cholestasis.
| S-EPMC10025474 | biostudies-literature