Functional interaction between angiotensin II receptor type 1 and chemokine (C-C motif) receptor 2 with implications for chronic kidney disease

PLoS One. 2015 Mar 25;10(3):e0119803. doi: 10.1371/journal.pone.0119803. eCollection 2015.

Abstract

Understanding functional interactions between G protein-coupled receptors is of great physiological and pathophysiological importance. Heteromerization provides one important potential mechanism for such interaction between different signalling pathways via macromolecular complex formation. Previous studies suggested a functional interplay between angiotensin II receptor type 1 (AT1) and Chemokine (C-C motif) Receptor 2 (CCR2). However the molecular mechanisms are not understood. We investigated AT1-CCR2 functional interaction in vitro using bioluminescence resonance energy transfer in HEK293 cells and in vivo using subtotal-nephrectomized rats as a well-established model for chronic kidney disease. Our data revealed functional heteromers of these receptors resulting in CCR2-Gαi1 coupling being sensitive to AT1 activation, as well as apparent enhanced β-arrestin2 recruitment with agonist co-stimulation that is synergistically reversed by combined antagonist treatment. Moreover, we present in vivo findings where combined treatment with AT1- and CCR2-selective inhibitors was synergistically beneficial in terms of decreasing proteinuria, reducing podocyte loss and preventing renal injury independent of blood pressure in the subtotal-nephrectomized rat model. Our findings further support a role for G protein-coupled receptor functional heteromerization in pathophysiology and provide insights into previous observations indicating the importance of AT1-CCR2 functional interaction in inflammation, renal and hypertensive disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Models, Animal
  • HEK293 Cells
  • Humans
  • Inositol Phosphates / metabolism
  • Kidney / metabolism
  • Nephrectomy
  • Rats
  • Receptor, Angiotensin, Type 1 / metabolism
  • Receptors, CCR2 / metabolism*
  • Renal Insufficiency, Chronic / metabolism*

Substances

  • Ccr2 protein, rat
  • Inositol Phosphates
  • Receptor, Angiotensin, Type 1
  • Receptors, CCR2

Grant support

This work was partly funded by Dimerix Bioscience Limited (www.dimerix.com), who was itself supported by the Australian Government's Commercialisation Australia scheme. Subsequently, this work was funded in part by the Australian Research Council (ARC; www.arc.gov.au) via Discovery Project Grant DP120101297 (KDGP, DJK and MAA). KDGP was an ARC Future Fellow (FT100100271) and is now a National Health and Medical Research Council of Australia (NHMRC; www.nhmrc.gov.au) RD Wright Fellow (1085842). EKMJ was funded by the Richard Walter Gibbon Medical Research Scholarship from The University of Western Australia (www.uwa.edu.au). DJK was funded by a NHMRC Senior Research Fellowship (566867). Other than EAM, JHW and KDGP, the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.