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Updated: May 22, 2026
06:55
Ileectomy-induced Bile Overaccumulation in Mouse Intestine
Published on: August 21, 2017
FXR signaling in the enterohepatic system
Tsutomu Matsubara1, Fei Li, Frank J Gonzalez
1Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States.
Molecular and Cellular Endocrinology
|May 22, 2012
Summary
The farnesoid X receptor (FXR) regulates bile acid homeostasis by controlling gene expression in the liver and intestine. FXR activation impacts bile acid synthesis, enterohepatic circulation, and lipid/glucose metabolism.
Area of Science:
- Hepatology
- Endocrinology
- Molecular Biology
Background:
- Enterohepatic circulation reabsorbs bile acids and steroid metabolites from the intestine to the liver.
- This process is tightly regulated by nuclear receptor signaling pathways.
- Bile acids influence gene expression via nuclear receptors like FXR, PXR, and VDR.
Purpose of the Study:
- To elucidate the role of FXR in regulating bile acid homeostasis.
- To understand how FXR bridges communication between the liver and small intestine.
- To explore FXR's impact on metabolic processes beyond bile acid regulation.
Main Methods:
- Analysis of nuclear receptor signaling in bile acid metabolism.
- Investigating FXR's high affinity for endogenous bile acids.
- Assessing FXR expression in liver and gut tissues.
Main Results:
- FXR acts as a key bile acid-responsive transcription factor.
- FXR controls bile acid levels, synthesis, and enterohepatic flow.
- FXR activation influences lipid and glucose metabolism and drug metabolism.
Conclusions:
- FXR is a critical regulator of bile acid homeostasis.
- FXR plays a significant role in maintaining metabolic balance.
- FXR signaling impacts multiple metabolic pathways, including lipid, glucose, and drug metabolism.
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