Artigo Acesso aberto Revisado por pares

PGC-1α negatively regulates hepatic FGF21 expression by modulating the heme/Rev-Erbα axis

2009; National Academy of Sciences; Volume: 106; Issue: 52 Linguagem: Inglês

10.1073/pnas.0912533106

ISSN

1091-6490

Autores

Jennifer L. Estall, Jorge L. Ruas, Cheol Soo Choi, Dina Laznik, Michael K. Badman, Eleftheria Maratos–Flier, Gerald I. Shulman, Bruce M. Spiegelman,

Tópico(s)

Epigenetics and DNA Methylation

Resumo

FGF21 is a hormone produced in liver and fat that dramatically improves peripheral insulin sensitivity and lipid metabolism. We show here that obese mice with genetically reduced levels of a key hepatic transcriptional coactivator, PGC-1alpha, have improved whole-body insulin sensitivity with increased levels of hepatic and circulating FGF21. Gain- and loss-of-function studies in primary mouse hepatocytes show that hepatic FGF21 levels are regulated by the expression of PGC-1alpha. Importantly, PGC-1alpha-mediated reduction of FGF21 expression is dependent on Rev-Erbalpha and the expression of ALAS-1. ALAS-1 is a PGC-1alpha target gene and the rate-limiting enzyme in the synthesis of heme, a ligand for Rev-Erbalpha. Modulation of intracellular heme levels mimics the effect of PGC-1alpha on FGF21 expression, and inhibition of heme biosynthesis completely abrogates the down-regulation of FGF21 in response to PGC-1alpha. Thus, PGC-1alpha can impact hepatic and systemic metabolism by regulating the levels of a nuclear receptor ligand.

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