Glucocorticoid signaling is context dependent, and in certain scenarios, glucocorticoid receptors (GRs) are able to engage with other members of the nuclear receptor subfamily. Glucocorticoid signaling can exert sexually dimorphic effects, suggesting a possible interaction with androgen sex hormones. We therefore set out to determine the crosstalk between glucocorticoids and androgens in metabolic tissues including white adipose tissue, liver and brown adipose tissue. Thereto we exposed male C57BL/6J mice to elevated levels of corticosterone in combination with an androgen receptor (AR) agonist or an AR antagonist. Systemic and local glucocorticoid levels were determined by mass spectrometry, and tissue expression of glucocorticoid-responsive genes and protein was measured by RT-qPCR and Western blot, respectively. To evaluate crosstalk in vitro, cultured white and brown adipocytes were exposed to a combination of corticosterone and an AR agonist. We found that AR agonism potentiated transcriptional response to GR in vitro in white and brown adipocytes and in vivo in white and brown adipose tissues. Conversely, AR antagonism substantially attenuated glucocorticoid signaling in white adipose tissue and liver. In white adipose tissue, this effect could partially be attributed to decreased 11B-hydroxysteroid dehydrogenase type 1-mediated glucocorticoid regeneration upon AR antagonism. In liver, attenuated GR activity was independent of active glucocorticoid ligand levels. We conclude that androgen signaling modulates GR transcriptional output in a tissue-specific manner.
Dieuwertje C E Spaanderman, Mark Nixon, Jacobus C Buurstede, Hetty H C M Sips, Maaike Schilperoort, Eline N Kuipers, Emma A Backer, Sander Kooijman, Patrick C N Rensen, Natalie Z M Homer, Brian R Walker, Onno C Meijer and Jan Kroon
Sjoerd D Joustra, Onno C Meijer, Charlotte A Heinen, Isabel M Mol, El Houari Laghmani, Rozemarijn M A Sengers, Gabriela Carreno, A S Paul van Trotsenburg, Nienke R Biermasz, Daniel J Bernard, Jan M Wit, Wilma Oostdijk, Ans M M van Pelt, Geert Hamer and Gerry T M Wagenaar
Loss-of-function mutations in the immunoglobulin superfamily member 1 (IGSF1) gene cause an X-linked syndrome of central hypothyroidism, macroorchidism, variable prolactin and GH deficiency, delayed pubertal testosterone rise, and obesity. To understand the pathophysiology of this syndrome, knowledge on IGSF1's place in normal development is imperative. Therefore, we investigated spatial and temporal protein and mRNA expression of IGSF1 in rats using immunohistochemistry, real-time quantitative PCR (qPCR), and in situ hybridization. We observed high levels of IGSF1 expression in the brain, specifically the embryonic and adult choroid plexus and hypothalamus (principally in glial cells), and in the pituitary gland (PIT1-lineage of GH, TSH, and PRL-producing cells). IGSF1 is also expressed in the embryonic and adult zona glomerulosa of the adrenal gland, islets of Langerhans of the pancreas, and costameres of the heart and skeletal muscle. IGSF1 is highly expressed in fetal liver, but is absent shortly after birth. In the adult testis, IGSF1 is present in Sertoli cells (epithelial stages XIII–VI), and elongating spermatids (stages X–XII). Specificity of protein expression was corroborated with Igsf1 mRNA expression in all tissues. The expression patterns of IGSF1 in the pituitary gland and testis are consistent with the pituitary hormone deficiencies and macroorchidism observed in patients with IGSF1 deficiency. The expression in the brain, adrenal gland, pancreas, liver, and muscle suggest IGSF1's function in endocrine physiology might be more extensive than previously considered.