Fasting-induced hepatic production of DHEA is regulated by PGC-1alpha, ERRalpha, and HNF4alpha.
Published
Journal Article
The transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha is involved in the coordinate induction of changes in gene expression in the liver that enable a homeostatic response to alterations in metabolic state, environmental cues, and nutrient availability. In exploring the specific pathways under PGC-1alpha regulation in the liver, we have made the surprising observation that this coactivator can induce the expression of CYP11A1 and CYP17A1, key rate-limiting enzymes involved in the initial steps of steroidogenesis. Both of these enzymes function to produce C(19)-steroids, converting cholesterol into pregnenolone, and then to dehydroepiandrosterone (DHEA). Estrogen-related receptor (ERR)-alpha mediates PGC-1alpha's induction of CYP11A1 and binds within the first intron of the CYP11A1 gene. Both ERR-alpha and hepatocyte nuclear factor-4alpha are required for PGC-1alpha-mediated induction of CYP17A1, and specific binding sites for these receptors have been identified in the regulatory regions of this gene. The potential physiological significance of these observations was highlighted in rats where fasting induced hepatic expression of PGC-1alpha and CYP17A1 and was associated with an increase in hepatic levels of DHEA. These data suggest that DHEA could be playing a role as an intracellular signaling molecule involved in modulating hepatic activity in response to fasting conditions.
Full Text
Duke Authors
- Chang, Ching-yi
- Gaillard, Stephanie
- Ilkayeva, Olga
- McDonnell, Donald Patrick
- Newgard, Christopher Bang
Cited Authors
- Grasfeder, LL; Gaillard, S; Hammes, SR; Ilkayeva, O; Newgard, CB; Hochberg, RB; Dwyer, MA; Chang, C-Y; McDonnell, DP
Published Date
- August 2009
Published In
Volume / Issue
- 23 / 8
Start / End Page
- 1171 - 1182
PubMed ID
- 19389810
Pubmed Central ID
- 19389810
Electronic International Standard Serial Number (EISSN)
- 1944-9917
Digital Object Identifier (DOI)
- 10.1210/me.2009-0024
Language
- eng
Conference Location
- United States