Estrogen Deficiency Promotes Hepatic Steatosis via a Glucocorticoid Receptor-Dependent Mechanism in Mice

Publication date: 6 March 2018
Source:Cell Reports, Volume 22, Issue 10
Author(s): Matthew A. Quinn, Xiaojiang Xu, Melania Ronfani, John A. Cidlowski
Glucocorticoids (GCs) are master regulators of systemic metabolism. Intriguingly, Cushing's syndrome, a disorder of excessive GCs, phenocopies several menopause-induced metabolic pathologies. Here, we show that the glucocorticoid receptor (GR) drives steatosis in hypogonadal female mice because hepatocyte-specific GR knockout mice are refractory to developing ovariectomy-induced steatosis. Intriguingly, transcriptional profiling revealed that ovariectomy elicits hepatic GC hypersensitivity globally. Hypogonadism-induced GC hypersensitivity results from a loss of systemic but not hepatic estrogen (E2) signaling, given that hepatocyte-specific E2 receptor deletion does not confer GC hypersensitivity. Mechanistically, enhanced chromatin recruitment and ligand-dependent hyperphosphorylation of GR underlie ovariectomy-induced glucocorticoid hypersensitivity. The dysregulated glucocorticoid-mediated signaling present in hypogonadal females is a product of increased follicle-stimulating hormone (FSH) production because FSH treatment in ovary-intact mice recapitulates glucocorticoid hypersensitivity similar to hypogonadal female mice. Our findings uncover a regulatory axis between estradiol, FSH, and hepatic glucocorticoid receptor signaling that, when disrupted, as in menopause, promotes hepatic steatosis.

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Teaser

Menopause is well known to promote metabolic dysfunction in females. Loss of systemic estrogen has long been thought to be the primary mediator of these metabolic defects in post-menopausal women. Quinn et al. reveal that stress hormones are, in fact, the primary contributor to metabolic disturbances following ovariectomy in mice.


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