Liver X receptor agonists decrease ENaC-mediated sodium transport in collecting duct cells

Am J Physiol Renal Physiol. 2012 Dec 15;303(12):F1610-6. doi: 10.1152/ajprenal.00283.2012. Epub 2012 Oct 17.

Abstract

Liver X receptors (LXRs) are nuclear receptors that regulate cholesterol, fatty acid, and glucose metabolism in various tissues. However, the renal action of LXRs is not well understood. Here we investigated the effects of LXR-activating ligands on modulation of epithelial sodium channel (ENaC)-mediated sodium transport in collecting duct cells. Exposure of the M1 cells to the synthetic LXR agonists T0901317 and GW3965 or the natural ligand 22R-hydroxycholesterol for 24 h decreased amiloride-sensitive sodium transport, corresponding with an increase of transepithelial resistance. The inhibition of amiloride-sensitive sodium transport after incubation with T0901317 or GW3965 was not mediated by a reduction of Na(+)/K(+)-ATPase-mediated basolateral sodium transport. On the other hand, T0901317 and GW3965 decreased mRNA abundance and membrane expression of ENaC. Preincubation the monolayer with GW3965 attenuated aldosterone-induced stimulation sodium transport. In primary cultures of collecting duct cells, T0901317 and GW3965 similarly inhibited ENaC transport function as in M1 cells. This is the first evidence showing LXR-activating ligands modulate ENaC-mediated sodium transport in collecting duct cells. These results suggest that LXRs may represent a novel therapeutic target for treatment of conditions with dysregulation of ENaC such as hypertension.

Publication types

  • Editorial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anticholesteremic Agents / pharmacology
  • Benzoates / pharmacology
  • Benzylamines / pharmacology
  • Biological Transport / drug effects
  • Cells, Cultured
  • Epithelial Sodium Channels / metabolism*
  • Hydrocarbons, Fluorinated / pharmacology
  • Hydroxycholesterols / pharmacology
  • Kidney Tubules, Collecting / cytology
  • Kidney Tubules, Collecting / drug effects
  • Kidney Tubules, Collecting / metabolism*
  • Ligands
  • Liver X Receptors
  • Mice
  • Orphan Nuclear Receptors / agonists*
  • Orphan Nuclear Receptors / metabolism*
  • Sodium / metabolism*
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Sulfonamides / pharmacology

Substances

  • Anticholesteremic Agents
  • Benzoates
  • Benzylamines
  • Epithelial Sodium Channels
  • GW 3965
  • Hydrocarbons, Fluorinated
  • Hydroxycholesterols
  • Ligands
  • Liver X Receptors
  • Orphan Nuclear Receptors
  • Sulfonamides
  • T0901317
  • 22-hydroxycholesterol
  • Sodium
  • Sodium-Potassium-Exchanging ATPase