Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA264053 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Acetylation of transcriptional regulators is normally dynamically regulated by nutrient status but is often persistently elevated in nutrient-excessive obesity conditions. We investigated the functional consequences of such aberrantly elevated acetylation of the nuclear receptor FXR as a model. Proteomic studies identified K217 as the FXR acetylation site in diet-induced obese mice. In vivo studies utilizing acetylation-mimic and -defective K217 mutants and gene expression profiling revealed that FXR acetylation increased proinflammatory gene expression, macrophage infiltration, and liver cytokine and triglyceride levels, impaired insulin signaling, and increased glucose intolerance. Mechanistically, acetylation of FXR blocked its interaction with the SUMO ligase PIASy and inhibited SUMO2 modification at K277, resulting in activation of inflammatory genes. SUMOylation of agonist-activated FXR increased its interaction with NF-κB but blocked that with RXRα, so that SUMO2-modified FXR was selectively recruited to and trans-repressed inflammatory genes without affecting FXR/RXRα target genes. A dysregulated Acetyl/SUMO switch of FXR in obesity may serve as a general mechanism for diminished anti-inflammatory response of other transcriptional regulators and provide potential therapeutic and diagnostic targets for obesity-related metabolic disorders. FXR-WT or the FXR-K217Q mutant was expressed in lean mice and FXR-WT or the FXR-K217R mutant was expressed in obese mice by adenoviral infection. One week after infection, mice were treated with GW4064 (30 mg/kg in corn oil) overnight before sacrifice and hepatic expression was analyzed by Illumina microarray.
2014-10-17 | E-GEOD-62414 | biostudies-arrayexpress
Project description:Acetylation of transcriptional regulators is normally dynamically regulated by nutrient status but is often persistently elevated in nutrient-excessive obesity conditions. We investigated the functional consequences of such aberrantly elevated acetylation of the nuclear receptor FXR as a model. Proteomic studies identified K217 as the FXR acetylation site in diet-induced obese mice. In vivo studies utilizing acetylation-mimic and -defective K217 mutants and gene expression profiling revealed that FXR acetylation increased proinflammatory gene expression, macrophage infiltration, and liver cytokine and triglyceride levels, impaired insulin signaling, and increased glucose intolerance. Mechanistically, acetylation of FXR blocked its interaction with the SUMO ligase PIASy and inhibited SUMO2 modification at K277, resulting in activation of inflammatory genes. SUMOylation of agonist-activated FXR increased its interaction with NF-κB but blocked that with RXRα, so that SUMO2-modified FXR was selectively recruited to and trans-repressed inflammatory genes without affecting FXR/RXRα target genes. A dysregulated Acetyl/SUMO switch of FXR in obesity may serve as a general mechanism for diminished anti-inflammatory response of other transcriptional regulators and provide potential therapeutic and diagnostic targets for obesity-related metabolic disorders.
2014-10-17 | GSE62414 | GEO
Project description:Metabolic dysfunction–associated steatohepatitis (MASH) is a progressive disease driven byobesity-related hepatic inflammation and oxidative stress. Recently, cysteine persulfidation (PSSH), a protective post-translational modification by hydrogen sulfide (H2S), was established to play a role in redox regulation. Despite the role of the liver in H2S metabolism, the function of PSSH in MASH remains underexplored. We demonstrated that H2S-producingenzymes are downregulated in both human and mouse livers with steatosis and fibrosis, resulting in a decline in global PSSH levels. Surprisingly, dimedone-switch mass spectrometry in dietary mouse models of distinct obesity-associated liver disease stages revealed dysregulated PSSH on specific proteins. In particular, increased hepatic PSSH levels of proteintyrosine phosphatases and redox regulators were found in advanced disease stages, suggesting a targeted adaptive response to oxidative stress. Overall, our findings demonstrated that impaired H2S production disrupts protective PSSH networks in MASH. However, selective PSSH preservation on redox-sensitive proteins may represent a compensatory mechanism, underscoring the therapeutic potential of persulfidation in restoring redox homeostasis during obesity-associated chronic liver disease.
2025-09-15 | PXD066952 | Pride
Project description:Roux-en-Y gastric bypass (RYGB) is highly effective in reversing obesity and associated diabetes. Recent observations in humans suggest a contributing role of increased circulating bile acids in mediating such effects. Here we use a diet-induced obesity mouse model and compared metabolic remission when bile flow was diverted through a gallbladder anastomosis to jejunum, ileum or duodenum (sham control). We found that only bile diversion to the ileum results in physiologic changes similar to RYGB including sustained improvements in weight, glucose tolerance and hepatic steatosis despite differential effects on hepatic gene expression. Circulating free fatty acids and triglycerides decrease while bile acids increase, particularly conjugated tauro-b-muricholic acid, an FXR antagonist. Activity of the hepatic FXR/FGF15 axis was reduced and associated with altered gut microbiota. Thus bile diversion, independent of surgical rearrangement of the gastrointestinal tract, imparts significant weight loss accompanied by improved glucose and lipid homeostasis that are hallmarks of RYGB. Total RNA from n = 5 DIO, n = 4 GB-IL, n = 5 RYGB mice livers was extracted of total RNA and submitted fro RNAseq
2015-05-13 | E-GEOD-68812 | biostudies-arrayexpress
Project description:Background & Aims: Wilson disease (WD) is an autosomal recessive disorder that results in excessive hepatic copper causing hepatic steatosis, inflammation, fibrosis, cirrhosis, and liver failure. Previous studies have revealed dysregulation of many FXR metabolic target genes in animal models of WD, including Bsep, the major determinant of bile flow. Approach & Results: We tested the hypothesis that the FXR-cistrome is decreased in Atp7b-/- mice in accord with dysregulated bile acid homeostasis. RNA-Seq and ChIP-Seq analyses of Atp7b-/- and wild-type (WT) mouse livers confirmed that significantly altered transcripts and FXR-binding events overlapped. Decreased FXR occupancy in Atp7b-/- versus WT mice was observed genes of metabolic pathways and bile acid homeostasis, while enrichment of FXR binding was observed pathways associated with cellular damage, such as the focal adhesion pathway. Consistent with decreased FXR function, serum and liver bile acid concentrations were higher in Atp7b-/- mice than in WT mice. Comparison of bile acid profiles in the serum of WD patients with “liver,” “neurological,” or “mixed” disease vs. healthy controls also revealed increases in specific bile acids in WD-liver vs. healthy controls. Conclusions: Atp7b-/- mice and WD patients exhibited changes in serum bile acid speciation, likely due to FXR dysfunction. These findings provide new insights into possible aberrant bile acid homeostasis in patients with WD.
2025-06-04 | GSE287020 | GEO
Project description:Background & Aims: Wilson disease (WD) is an autosomal recessive disorder that results in excessive hepatic copper causing hepatic steatosis, inflammation, fibrosis, cirrhosis, and liver failure. Previous studies have revealed dysregulation of many FXR metabolic target genes in animal models of WD, including Bsep, the major determinant of bile flow. Approach & Results: We tested the hypothesis that the FXR-cistrome is decreased in Atp7b-/- mice in accord with dysregulated bile acid homeostasis. RNA-Seq and ChIP-Seq analyses of Atp7b-/- and wild-type (WT) mouse livers confirmed that significantly altered transcripts and FXR-binding events overlapped. Decreased FXR occupancy in Atp7b-/- versus WT mice was observed genes of metabolic pathways and bile acid homeostasis, while enrichment of FXR binding was observed pathways associated with cellular damage, such as the focal adhesion pathway. Consistent with decreased FXR function, serum and liver bile acid concentrations were higher in Atp7b-/- mice than in WT mice. Comparison of bile acid profiles in the serum of WD patients with “liver,” “neurological,” or “mixed” disease vs. healthy controls also revealed increases in specific bile acids in WD-liver vs. healthy controls. Conclusions: Atp7b-/- mice and WD patients exhibited changes in serum bile acid speciation, likely due to FXR dysfunction. These findings provide new insights into possible aberrant bile acid homeostasis in patients with WD.
2025-06-04 | GSE286956 | GEO
Project description:Bile acid (BA) metabolism must be tightly regulated because BAs serve as metabolic signaling molecules but become cytotoxic at high levels. The farnesoid X receptor (FXR) is a crucial bile acid sensor, but our understanding of its regulation and coordination with other transcription factors is limited. Here, we found that B cell lymphoma 6 (Bcl6) functions along with FXR to control bile acid levels. We found that mice lacking hepatic BCL6 (Bcl6LKO) had increased BA synthesis and serum levels. In line with this, Bcl6LKO mice had elevated serum cholesterol, the upstream substrate for BA synthesis, as well as reduced expression of the hepatic BA re-uptake transporter sodium-taurocholate cotransporting polypeptide (NTCP). Furthermore, loss of BCL6 reduced hepatic fibroblast growth factor 4 (FGFR4) expression, causing dysregulated entero-hepatic BA feedback signaling. To better understand the relative contribution of BCL6 and FXR in regulating BA homeostasis, we generated mice with a combined deletion of hepatic BCL6 and FXR (Bcl6LKOFxrKO). Critically, combined deletion of FXR and hepatic BCL6 caused massive elevations in BA synthesis/levels compared to loss of Fxr or Bcl6 alone, which resulted in cholestatic liver damage. Mechanistically, we found that Bcl6LKO FxrKO mice had an almost complete loss of hepatic Shp expression, causing high levels of the rate-limiting BA synthesis enzyme CYP7A1. Together, these findings demonstrate that BCL6 and FXR function together to limit BA synthesis and protect the liver from cholestatic injury.
2026-02-11 | GSE290307 | GEO
Project description:Bile acid (BA) metabolism must be tightly regulated because BAs serve as metabolic signaling molecules but become cytotoxic at high levels. The farnesoid X receptor (FXR) is a crucial bile acid sensor, but our understanding of its regulation and coordination with other transcription factors is limited. Here, we found that B cell lymphoma 6 (Bcl6) functions along with FXR to control bile acid levels. We found that mice lacking hepatic BCL6 (Bcl6LKO) had increased BA synthesis and serum levels. In line with this, Bcl6LKO mice had elevated serum cholesterol, the upstream substrate for BA synthesis, as well as reduced expression of the hepatic BA re-uptake transporter sodium-taurocholate cotransporting polypeptide (NTCP). Furthermore, loss of BCL6 reduced hepatic fibroblast growth factor 4 (FGFR4) expression, causing dysregulated entero-hepatic BA feedback signaling. To better understand the relative contribution of BCL6 and FXR in regulating BA homeostasis, we generated mice with a combined deletion of hepatic BCL6 and FXR (Bcl6LKOFxrKO). Critically, combined deletion of FXR and hepatic BCL6 caused massive elevations in BA synthesis/levels compared to loss of Fxr or Bcl6 alone, which resulted in cholestatic liver damage. Mechanistically, we found that Bcl6LKO FxrKO mice had an almost complete loss of hepatic Shp expression, causing high levels of the rate-limiting BA synthesis enzyme CYP7A1. Together, these findings demonstrate that BCL6 and FXR function together to limit BA synthesis and protect the liver from cholestatic injury.
2026-02-11 | GSE290309 | GEO
Project description:Bile acid (BA) metabolism must be tightly regulated because BAs serve as metabolic signaling molecules but become cytotoxic at high levels. The farnesoid X receptor (FXR) is a crucial bile acid sensor, but our understanding of its regulation and coordination with other transcription factors is limited. Here, we found that B cell lymphoma 6 (Bcl6) functions along with FXR to control bile acid levels. We found that mice lacking hepatic BCL6 (Bcl6LKO) had increased BA synthesis and serum levels. In line with this, Bcl6LKO mice had elevated serum cholesterol, the upstream substrate for BA synthesis, as well as reduced expression of the hepatic BA re-uptake transporter sodium-taurocholate cotransporting polypeptide (NTCP). Furthermore, loss of BCL6 reduced hepatic fibroblast growth factor 4 (FGFR4) expression, causing dysregulated entero-hepatic BA feedback signaling. To better understand the relative contribution of BCL6 and FXR in regulating BA homeostasis, we generated mice with a combined deletion of hepatic BCL6 and FXR (Bcl6LKOFxrKO). Critically, combined deletion of FXR and hepatic BCL6 caused massive elevations in BA synthesis/levels compared to loss of Fxr or Bcl6 alone, which resulted in cholestatic liver damage. Mechanistically, we found that Bcl6LKO FxrKO mice had an almost complete loss of hepatic Shp expression, causing high levels of the rate-limiting BA synthesis enzyme CYP7A1. Together, these findings demonstrate that BCL6 and FXR function together to limit BA synthesis and protect the liver from cholestatic injury.
2026-02-11 | GSE296552 | GEO
Project description:Metabolic dysfunction–associated steatohepatitis (MASH), marked by hepatic steatosis and inflammation, is a major risk for cirrhosis and liver cancer. Obesity-induced oxidative stress plays a central role in MASH promoting protein damage and dysfunction. Cysteine persulfidation (PSSH), a post-translational modification regulated by hydrogen sulfide (H2S), is involved in protein stability and cellular protection. However, the role of PSSH in MASH is poorly understood. We found that H2S-producing enzymes are downregulated in livers with fibrosis and inflammation, leading to decreased hepatic PSSH. Using dimedone-switch-based mass spectrometry, we mapped the alterations in the liver persulfidome during diet-induced fibrosis and inflammation. While the levels of H2S-producing enzymes dropped, some proteins, including protein tyrosine phosphatases (PTPs) and redox regulators, showed increased PSSH. This change suggests that H2S-mediated persulfidation helps protect proteins from oxidative damage. Overall, decreased H2S enzyme expression and reduced PSSH may impair protection against oxidative stress, contributing to liver dysfunction in obesity.
2025-08-04 | PXD057932 | Pride