Cholesterol 7 alpha-hydroxylase plays a crucial role in cholesterol homeostasis. We investigated the regulation of this enzyme in the hamster, a suitable animal model for studying cholesterol metabolism. DNase I hypersensitivity assay revealed the…
The gene encoding cholesterol 7 alpha-hydroxylase (CYP7A), the rate-limiting enzyme in bile acid synthesis, is transcriptionally regulated by bile acids and hormones. Previously, we have identified two bile acid response elements (BARE) in the…
The cholesterol 7 alpha-hydroxylase gene (CYP7A) is transcriptionally regulated by a number of factors, including hormones, bile acids, and diurnal rhythm. Previous studies have identified a region from nucleotides (nt) -74 to -55 of the rat CYP7A…
A stable HepG2 cell line harboring a human cholesterol 7 alpha-hydroxylase (CYP7A) minigene/luciferase reporter gene construct was selected for studying transcriptional regulation of CYP7A gene promoter. Insulin and phorbol
The cholesterol 7alpha-hydroxylase gene (CYP7A) is transcriptionally regulated by a number of factors, including hormones, bile acids, and diurnal rhythm. Previous studies have identified a region from nucleotides (nt) -74 to -55 of the rat CYP7A…
The gene encoding cholesterol 7alpha-hydroxylase (CYP7A), the rate-limiting enzyme in bile acid synthesis, is transcriptionally regulated by bile acids and hormones. Previously, we have identified two bile acid response elements (BARE) in the…
The transcriptional regulation of the rat cholesterol 7 alpha-hydroxylase gene (CYP7) by hormones and signal transduction pathways was studied by transient transfection assay of the promoter activity. HepG2 cells were transfected with deletion…
The transcriptional activity of the cholesterol 7 alpha-hydroxylase gene CYP7A is repressed by bile acids. Taurine conjugates of chenodeoxycholate and deoxycholate, but not cholate and ursodeoxycholate, inhibited the CYP7A promoter/luciferase…
The activity of the rat CYP7A/luciferase reporter gene was increased five-fold by all-trans retinoic acid (atRA) or 9-cis retinoic acid (9cRA) in transient transfection assay in HepG2 cells. Cotransfection with retinoid X receptor (RXR) stimulated…
The expression of cholesterol 7 alpha-hydroxylase mRNA levels in confluent HepG2 cultures was reduced by tauro- or glyco-conjugates of deoxycholate and chenodeoxycholate, but not by cholate. Ursodeoxycholates, on the other hand, stimulated the mRNA…
Cholesterol 7 alpha-hydroxylase is the rate limiting enzyme in bile acid biosynthesis and plays an important role in cholesterol homeostasis. The Golden Syrian hamster has been used as an animal model for the study of atherosclerosis and cholesterol…