Adrenal and Ovarian Phenotype of a Tissue-Specific Urocortin 2-Overexpressing Mouse Model

Endocrinology. 2015 Jul;156(7):2646-56. doi: 10.1210/en.2014-1971. Epub 2015 May 5.

Abstract

Urocortin 2 (UCN2) is a neuropeptide of the CRH family, involved in homeostatic mechanisms, the stress response, and control of anxiety. To elucidate the effects of UCN2 on steroidogenesis, we developed a mouse model that allows a Cre recombinase-determined conditional overexpression of UCN2 (UCN2-COE). In these mice SF1-Cre-driven overexpression of UCN2 was restricted to the adrenal glands, gonads, and parts of the hypothalamus. UCN2-COE animals of both sexes revealed significantly higher plasma UCN2 levels and significantly higher UCN2 expression levels in the adrenals and ovaries. In contrast, the baseline expression of UCN2 was already high in the testes of control mice with no further increase achievable in UCN2-COE animals. Adrenal steroidogenesis of UCN2-COE animals was investigated under baseline conditions, upon an ACTH stimulation test, and following a restraint stress test. A tendency toward lower expression of steroidogenic enzymes was detectable in UCN2-COE animals of both sexes with slight differences between males and females. A similar reduction in the expression levels of the final steps of ovarian steroidogenesis, accompanied by reduced plasma estradiol levels, was observed in female UCN2-COE animals. Thus, adrenal UCN2 overexpression resulted in down-regulation of adrenal steroidogenesis, suggesting a reduction in the stress response in the mouse (stress coping behavior). Similarly, UCN2 overexpression in the ovaries caused a decrease in steroidogenesis and reduction of follicles that had undergone ovulation. Nevertheless, this finding was not associated with reduced fertility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 17-Hydroxysteroid Dehydrogenases / genetics
  • 17-alpha-Hydroxypregnenolone / metabolism
  • 3-Hydroxysteroid Dehydrogenases / drug effects
  • 3-Hydroxysteroid Dehydrogenases / genetics
  • Adrenal Glands / drug effects
  • Adrenal Glands / metabolism*
  • Adrenocorticotropic Hormone / pharmacology
  • Animals
  • Aromatase / metabolism
  • Cholesterol Side-Chain Cleavage Enzyme / drug effects
  • Cholesterol Side-Chain Cleavage Enzyme / genetics
  • Corticotropin-Releasing Hormone / genetics*
  • Cytochrome P-450 CYP11B2 / drug effects
  • Cytochrome P-450 CYP11B2 / genetics
  • Estradiol / metabolism
  • Female
  • Gene Knock-In Techniques
  • Gonadal Steroid Hormones
  • Male
  • Mice
  • Ovary / anatomy & histology
  • Ovary / metabolism*
  • Phenotype
  • Phosphoproteins / drug effects
  • Phosphoproteins / genetics
  • Progesterone / metabolism
  • RNA, Messenger / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Steroid 11-beta-Hydroxylase / drug effects
  • Steroid 11-beta-Hydroxylase / genetics
  • Steroid 17-alpha-Hydroxylase / genetics
  • Testis / metabolism
  • Urocortins / genetics*

Substances

  • Gonadal Steroid Hormones
  • Phosphoproteins
  • RNA, Messenger
  • Urocortins
  • steroidogenic acute regulatory protein
  • urocortin 2, mouse
  • 17-alpha-Hydroxypregnenolone
  • Progesterone
  • Estradiol
  • Adrenocorticotropic Hormone
  • Corticotropin-Releasing Hormone
  • 17-Hydroxysteroid Dehydrogenases
  • 3-Hydroxysteroid Dehydrogenases
  • hydroxysteroid (17-beta) dehydrogenase 1, mouse
  • Aromatase
  • Steroid 17-alpha-Hydroxylase
  • Cytochrome P-450 CYP11B2
  • Steroid 11-beta-Hydroxylase
  • Cholesterol Side-Chain Cleavage Enzyme