Bile acids play important roles in the regulation of lipid, glucose, and energy homeostasis. Recent studies suggest that glucose regulates gene transcription in the liver. The aim of this study was to investigate the potential role of glucose in regulation of bile acid synthesis in human hepatocytes. High glucose stimulated bile acid synthesis and induced mRNA expression of cholesterol 7alpha-hydroxylase (CYP7A1), the key regulatory gene in bile acid synthesis. Activation of an AMP-activated protein kinase (AMPK) decreased CYP7A1 mRNA, hepatocyte nuclear factor 4alpha (HNF4alpha) protein, and binding to CYP7A1 chromatin. Glucose increased ATP levels to inhibit AMPK and induce HNF4alpha to stimulate CYP7A1 gene transcription. Furthermore, glucose increased histone acetylation and decreased H3K9 di- and tri-methylation in the CYP7A1 chromatin. Knockdown of ATP-citrate lyase, which converts citrate to acetyl-CoA, decreased histone acetylation and attenuated glucose induction of CYP7A1 mRNA expression. These results suggest that glucose signaling also induces CYP7A1 gene transcription by epigenetic regulation of the histone acetylation status. This study uncovers a novel link between hepatic glucose metabolism and bile acid synthesis. Glucose induction of bile acid synthesis may have an important implication in metabolic control of glucose, lipid, and energy homeostasis under normal and diabetic conditions.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2842145PMC
http://dx.doi.org/10.1194/jlr.M002782DOI Listing

Publication Analysis

Top Keywords

bile acid
20
acid synthesis
20
gene transcription
16
glucose
12
histone acetylation
12
cholesterol 7alpha-hydroxylase
8
human hepatocytes
8
energy homeostasis
8
mrna expression
8
cyp7a1 mrna
8

Similar Publications

Characterization of insulin and bile acid complexes in liposome by different mass spectrometry techniques.

Anal Bioanal Chem

January 2025

Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, China.

Insulin bound with ligand molecules can improve its bioavailability in oral formulations. In this work, the interactions between insulin and bile acids of taurocholic acid (TCA) and glycocholic acid (GCA) are characterized using different mass spectrometry (MS) methods. Electrospray (ESI)-MS analysis revealed that GCA and TCA could interact with insulin individually or together through non-covalent bonds, and the products included mGCA-insulin, nTCA-insulin, and mGCA-nTCA-insulin complexes.

View Article and Find Full Text PDF

Through biochemical transformation of host-derived bile acids (BAs), gut bacteria mediate host-microbe crosstalk and sit at the interface of nutrition, the microbiome, and disease. BAs play a crucial role in human health by facilitating the absorption of dietary lipophilic nutrients, interacting with hormone receptors to regulate host physiology, and shaping gut microbiota composition through antimicrobial activity. Bile acid deconjugation by bacterial bile salt hydrolase (BSH) has long been recognized as the first necessary BA modification required before further transformations can occur.

View Article and Find Full Text PDF

Background: Sepsis is a severe complication in leukemia patients, contributing to high mortality rates. Identifying early predictors of sepsis is crucial for timely intervention. This study aimed to develop and validate a predictive model for sepsis risk in leukemia patients using machine learning techniques.

View Article and Find Full Text PDF

Background: Studies using machine learning to identify the target characteristics and develop predictive models for coronary artery disease severity in patients with premature myocardial infarction (PMI) are limited.

Methods: In this observational study, 1111 PMI patients (≤55 years) at Tianjin Chest Hospital from 2017 to 2022 were selected and divided according to their SYNTAX scores into a low-risk group (≤22) and medium-high-risk group (>22). These groups were further randomly assigned to a training or test set in a ratio of 7:3.

View Article and Find Full Text PDF

Poor Outcome of Rare Lactobacillus Bacteremia and Endocarditis in a Patient With Frequent Consumption of Live Culture Yogurts.

J Community Hosp Intern Med Perspect

January 2025

Division of Infectious Disease, Department of Internal Medicine, Naples Comprehensive Health, Naples, FL, USA.

is a gram-positive bacterium commonly found in dairy products and used as a probiotic due to its resistance to acid and bile. While generally considered safe, rare cases of bacteremia and endocarditis have been reported, primarily in individuals with significant risk factors. This report discusses an elderly male with a history of cardiovascular diseases, diabetes, and asthma, who developed bacteremia and endocarditis after consuming large quantities of Greek yogurt.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!