The Selective Estrogen Receptor Modulator Raloxifene Regulates Arginine-Vasopressin Gene Expression in Human Female Neuroblastoma Cells Through G Protein-Coupled Estrogen Receptor and ERK Signaling

Endocrinology. 2015 Oct;156(10):3706-16. doi: 10.1210/en.2014-2010. Epub 2015 Jul 22.

Abstract

The selective estrogen receptor modulator raloxifene reduces blood pressure in hypertensive postmenopausal women. In the present study we have explored whether raloxifene regulates gene expression of arginine vasopressin (AVP), which is involved in the pathogenesis of hypertension. The effect of raloxifene was assessed in human female SH-SY5Y neuroblastoma cells, which have been recently identified as a suitable cellular model to study the estrogenic regulation of AVP. Raloxifene, within a concentration ranging from 10(-10) M to 10(-6) M, decreased the mRNA levels of AVP in SH-SY5Y cells with maximal effect at 10(-7) M. This effect of raloxifene was imitated by an agonist (±)-1-[(3aR*,4S*,9bS*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-8-yl]-ethanone of G protein-coupled estrogen receptor-1 (GPER) and blocked by an antagonist (3aS*,4R*,9bR*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta[c]quinoline of GPER and by GPER silencing. Raloxifene induced a time-dependent increase in the level of phosphorylated ERK1 and ERK2, by a mechanism blocked by the GPER antagonist. The treatment of SH-SY5Y cells with either a MAPK/ERK kinase 1/2-specific inhibitor (1,4-diamino-2, 3-dicyano-1,4-bis(2-aminophenylthio)butadine) or a protein kinase C inhibitor (sotrastaurin) blocked the effects of raloxifene on the phosphorylation of ERK1/2 and the regulation of AVP mRNA levels. These results reveal a mechanism mediating the regulation of AVP expression by raloxifene, involving the activation of GPER, which in turn activates protein kinase C, MAPK/ERK kinase, and ERK. The regulation of AVP by raloxifene and GPER may have implications for the treatment of blood hypertension(.).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arginine Vasopressin / genetics*
  • Blotting, Western
  • Cell Line, Tumor
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects*
  • Humans
  • MAP Kinase Signaling System / drug effects*
  • Neuroblastoma / genetics
  • Neuroblastoma / metabolism
  • Neuroblastoma / pathology
  • Phosphorylation / drug effects
  • Protein Kinase C / antagonists & inhibitors
  • Protein Kinase C / metabolism
  • Pyrroles / pharmacology
  • Quinazolines / pharmacology
  • RNA Interference
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Raloxifene Hydrochloride / pharmacology*
  • Receptors, Estrogen / genetics
  • Receptors, Estrogen / metabolism*
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Selective Estrogen Receptor Modulators / pharmacology

Substances

  • GPER1 protein, human
  • Pyrroles
  • Quinazolines
  • RNA, Messenger
  • Receptors, Estrogen
  • Receptors, G-Protein-Coupled
  • Selective Estrogen Receptor Modulators
  • Arginine Vasopressin
  • Raloxifene Hydrochloride
  • sotrastaurin
  • Protein Kinase C
  • Extracellular Signal-Regulated MAP Kinases