title: Cholesterol-derived glucocorticoids control early fate specification in embryonic stem cells.
abstract: Aside from its role in cell membrane integrity, cholesterol is a key component in steroid hormone production. The vital functions of steroid hormones such as estrogen, testosterone, glucocorticoids (Gcrts) and mineralocorticoids (Mnrts) in perinatal and adult life are well understood; however, their role during early embryonic development remains largely unexplored. Here we show that siRNA-mediated perturbation of steroid hormone production during mesoderm formation has important consequences on cardiac differentiation in mouse embryonic stem cells (mESC). Both Gcrts and Mnrts are capable of driving cardiac differentiation in mESC. Interestingly, the Gcrt receptor is widely expressed during gastrulation in the mouse, and is exclusively localized in the nuclei-and thus active-in visceral endoderm cells, suggesting that it functions much earlier than previously anticipated. We therefore studied Gcrt signaling in mESC as a model of the gastrulating embryo, and found that Gcrt signaling regulates expression of the transcription factor Hnf4a and the secreted Nodal and BMP inhibitor Cer1 in the early visceral endoderm. RNAi-mediated knockdown of Gcrt function blocked cardiomyocyte differentiation, with limited effects on other cardiovascular cell types including vascular endothelial cells and smooth muscle. Furthermore, the cardiogenic effect of Gcrts required Hnf4a and paracrine Cer1. These results establish a novel function for cholesterol-derived steroid hormones and identify Gcrt signaling in visceral endoderm cells as a regulator of Cer1 and cardiac fate.
authors.affiliation: Muscle Development and Regeneration Program, Sanford-Burnham Medical Research Institute, La Jolla, CA, USA; Graduate Program in Molecular Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Cabral-Teixeira
authors.affiliation: Division of Cardiovascular Diseases and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Almudena
authors.initials: A
authors.lastname: Martinez-Fernandez
authors.affiliation: Muscle Development and Regeneration Program, Sanford-Burnham Medical Research Institute, La Jolla, CA, USA; Graduate School of Biomedical Sciences, Sanford-Burnham Medical Research Institute, La Jolla, CA, USA.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Cai
authors.affiliation: Division of Cardiovascular Diseases and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Andre
authors.initials: A
authors.lastname: Terzic
authors.affiliation: Muscle Development and Regeneration Program, Sanford-Burnham Medical Research Institute, La Jolla, CA, USA; Department of Bioengineering, University of California San Diego, La Jolla, CA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Mercola
authors.affiliation: Muscle Development and Regeneration Program, Sanford-Burnham Medical Research Institute, La Jolla, CA, USA. Electronic address: ewillems@sanfordburnham.org.
authors.forename: Erik
authors.initials: E
authors.lastname: Willems
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D019070:Cell Lineage / Q000187:drug effects*; D002784:Cholesterol / Q000737:chemistry*; D016207:Cytokines; D004707:Endoderm / Q000166:cytology; D005938:Glucocorticoids / Q000494:pharmacology*; D051557:Hepatocyte Nuclear Factor 4 / Q000378:metabolism; D008648:Mesoderm / Q000166:cytology; D051379:Mice; D008954:Models, Biological; D000066450:Mouse Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D009206:Myocardium / Q000166:cytology; D011506:Proteins / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014781:Viscera / Q000166:cytology
chemical_list: C110586:Cer1 protein, mouse; D016207:Cytokines; D005938:Glucocorticoids; D051557:Hepatocyte Nuclear Factor 4; C496593:Hnf4a protein, mouse; D011506:Proteins; D002784:Cholesterol