Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2009-8-31
pubmed:abstractText
Essential fatty acid (EFA) deficiency in mice has been associated with increased bile production, which is mainly determined by the enterohepatic circulation (EHC) of bile salts. To establish the mechanism underlying the increased bile production, we characterized in detail the EHC of bile salts in EFA-deficient mice using stable isotope technique, without interrupting the normal EHC. Farnesoid X receptor (FXR) has been proposed as an important regulator of bile salt synthesis and homeostasis. In Fxr(-/-) mice we additionally investigated to what extent alterations in bile production during EFA deficiency were FXR dependent. Furthermore, we tested in differentiating Caco-2 cells the effects of EFA deficiency on expression of FXR-target genes relevant for feedback regulation of bile salt synthesis. EFA deficiency-enhanced bile flow and biliary bile salt secretion were associated with elevated bile salt pool size and synthesis rate (+146 and +42%, respectively, P < 0.05), despite increased ileal bile salt reabsorption (+228%, P < 0.05). Cyp7a1 mRNA expression was unaffected in EFA-deficient mice. However, ileal mRNA expression of Fgf15 (inhibitor of bile salt synthesis) was significantly reduced, in agreement with absent inhibition of the hepatic bile salt synthesis. Bile flow and biliary secretion were enhanced to the same extent in EFA-deficient wild-type and Fxr(-/-) mice, indicating contribution of other factors besides FXR in regulation of EHC during EFA deficiency. In vitro experiments show reduced induction of mRNA expression of relevant genes upon chenodeoxycholic acid and a selective FXR agonist GW4064 stimulation in EFA-deficient Caco-2 cells. In conclusion, our data indicate that EFA deficiency is associated with interrupted negative feedback of bile salt synthesis, possibly because of reduced ileal Fgf15 expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Bile Acids and Salts, http://linkedlifedata.com/resource/pubmed/chemical/Chenodeoxycholic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol 7-alpha-Hydroxylase, http://linkedlifedata.com/resource/pubmed/chemical/Fatty Acids, Essential, http://linkedlifedata.com/resource/pubmed/chemical/Fibroblast Growth Factors, http://linkedlifedata.com/resource/pubmed/chemical/GW 4064, http://linkedlifedata.com/resource/pubmed/chemical/Isoxazoles, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cytoplasmic and Nuclear, http://linkedlifedata.com/resource/pubmed/chemical/cytochrome P450 7A1, mouse, http://linkedlifedata.com/resource/pubmed/chemical/farnesoid X-activated receptor, http://linkedlifedata.com/resource/pubmed/chemical/fibroblast growth factor 15, mouse
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1522-1547
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
297
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G520-31
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:19608735-Animals, pubmed-meshheading:19608735-Bile, pubmed-meshheading:19608735-Bile Acids and Salts, pubmed-meshheading:19608735-Caco-2 Cells, pubmed-meshheading:19608735-Chenodeoxycholic Acid, pubmed-meshheading:19608735-Cholesterol 7-alpha-Hydroxylase, pubmed-meshheading:19608735-Enterohepatic Circulation, pubmed-meshheading:19608735-Fatty Acids, Essential, pubmed-meshheading:19608735-Feedback, Physiological, pubmed-meshheading:19608735-Fibroblast Growth Factors, pubmed-meshheading:19608735-Humans, pubmed-meshheading:19608735-Intestinal Absorption, pubmed-meshheading:19608735-Intestine, Small, pubmed-meshheading:19608735-Isoxazoles, pubmed-meshheading:19608735-Kinetics, pubmed-meshheading:19608735-Male, pubmed-meshheading:19608735-Mice, pubmed-meshheading:19608735-Mice, Inbred C57BL, pubmed-meshheading:19608735-Mice, Knockout, pubmed-meshheading:19608735-RNA, Messenger, pubmed-meshheading:19608735-Receptors, Cytoplasmic and Nuclear
pubmed:year
2009
pubmed:articleTitle
Effects of essential fatty acid deficiency on enterohepatic circulation of bile salts in mice.
pubmed:affiliation
Department of Pediatrics, Beatrix Children's Hospital, Groningen University Institute for Drug Exploration, Center for Liver, Digestive and Metabolic Diseases, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't