Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Navigation/Suche
- Forscher*innen
- Institutionen
- Projekte
- Publikationen
- Partner
- Geldgeber
- Ausstattung
- Knowhow
- Forschungsfelder
"Köpfe" der aktuellen Meldungen:
Gewählte Publikation:
SHR Neuro Krebs Kardio Lipid Stoffw Microb
Chennamsetty, I; Claudel, T; Kostner, KM; Baghdasaryan, A; Kratky, D; Levak-Frank, S; Frank, S; Gonzalez, FJ; Trauner, M; Kostner, GM.
Farnesoid X receptor represses hepatic human APOA gene expression.
J Clin Invest. 2011; 121(9):3724-3734
Doi: 10.1172/JCI45277
[OPEN ACCESS]
Web of Science
PubMed
FullText
FullText_MUG
- Führende Autor*innen der Med Uni Graz
- Chennamsetty Indumathi
- Kostner Gerhard
- Co-Autor*innen der Med Uni Graz
- Baghdasaryan Anna
- Claudel Thierry
- Frank Sasa
- Kratky Dagmar
- Levak Sanja
- Trauner Michael
- Altmetrics:
- Dimensions Citations:
- Plum Analytics:
- Scite (citation analytics):
- Abstract:
- High plasma concentrations of lipoprotein(a) [Lp(a), which is encoded by the APOA gene] increase an individual's risk of developing diseases, such as coronary artery diseases, restenosis, and stroke. Unfortunately, increased Lp(a) levels are minimally influenced by dietary changes or drug treatment. Further, the development of Lp(a)-specific medications has been hampered by limited knowledge of Lp(a) metabolism. In this study, we identified patients suffering from biliary obstructions with very low plasma Lp(a) concentrations that rise substantially after surgical intervention. Consistent with this, common bile duct ligation in mice transgenic for human APOA (tg-APOA mice) lowered plasma concentrations and hepatic expression of APOA. To test whether farnesoid X receptor (FXR), which is activated by bile acids, was responsible for the low plasma Lp(a) levels in cholestatic patients and mice, we treated tg-APOA and tg-APOA/Fxr-/- mice with cholic acid. FXR activation markedly reduced plasma concentrations and hepatic expression of human APOA in tg-APOA mice but not in tg-APOA/Fxr-/- mice. Incubation of primary hepatocytes from tg-APOA mice with bile acids dose dependently downregulated APOA expression. Further analysis determined that the direct repeat 1 element between nucleotides -826 and -814 of the APOA promoter functioned as a negative FXR response element. This motif is also bound by hepatocyte nuclear factor 4α (HNF4α), which promotes APOA transcription, and FXR was shown to compete with HNF4α for binding to this motif. These findings may have important implications in the development of Lp(a)-lowering medications.
- Find related publications in this database (using NLM MeSH Indexing)
- Animals -
- Apolipoproteins A - genetics Apolipoproteins A - metabolism
- Bile Acids and Salts - administration & dosage Bile Acids and Salts - blood
- Cells, Cultured -
- Female -
- Gene Expression -
- Hepatocyte Nuclear Factor 4 - genetics Hepatocyte Nuclear Factor 4 - metabolism
- Humans -
- Jaundice, Obstructive - blood
- Liver - cytology Liver - physiology
- Mice -
- Mice, Knockout -
- Mice, Transgenic -
- Promoter Regions, Genetic -
- RNA, Messenger - metabolism
- Random Allocation -
- Receptors, Cytoplasmic and Nuclear - genetics Receptors, Cytoplasmic and Nuclear - metabolism