(Pro) renin Receptor-Dependent Induction of Profibrotic Factors Is Mediated by COX-2/EP4/NOX-4/Smad Pathway in Collecting Duct Cells

Reyes-Martinez, C; Nguyen, QM; Kassan, M; Gonzalez, AA

Keywords: reactive oxygen species, collecting duct renin, intrarenal renin-angiotensin system, (Pro) renin receptor, cyclooxygenase inhibition

Abstract

The binding of prorenin to the (pro) renin receptor (PRR) triggers the activation of MAPK/ERK1/2 pathway, induction of cyclooxygenase-2 (COX-2), NOX-4-dependent production of reactive oxygen species (ROS), and the induction of transforming growth factor beta (TGF-beta) and profibrotic factors connecting tissue growth factor (CTGF) and plasminogen activator inhibitor (PAI-I) in collecting duct (CD) cells. However, the role of COX-2 and the intracellular pathways involved are not clear. We hypothesized that the PRR activation increases profibrotic factors through COX-2-mediated PGE2 activation of E prostanoid receptor 4 (EP4), upregulation of NOX-4/ROS production, and activation of Smad pathway in mouse CD cells. Recombinant prorenin increased ROS production and protein levels of CTGF, PAI-I, and TGF-beta in M-1 CD cell line. Inhibition of MAPK, NOX-4, and COX-2 prevented this effect. Inhibition of MEK, COX-2, and EP4 also prevented the upregulation of NOX-4. Because TGF-beta activates Smad pathway, we evaluate the phosphorylation of Smad2 and 3. COX-2 inhibition or EP4 antagonism significantly prevented phosphorylation of Smad 2/3. Mice that were infused with recombinant prorenin showed an induction in the expression of CTGF, PAI-I, TGF-beta, fibronectin, and collagen I in isolated collecting ducts as well as the expression of alpha smooth muscle actin (alpha-SMA) in renal tissues. COX-2 inhibition prevented this induction. These results indicate that the induction of TGF-beta, CTGF, PAI-I, and ROS occurs through PRR-dependent activation of MAPK and NOX-4; however, this mechanism depends on COX-2-derived PGE2 production and the activation of EP4 and Smad pathway.

Más información

Título según WOS: (Pro) renin Receptor-Dependent Induction of Profibrotic Factors Is Mediated by COX-2/EP4/NOX-4/Smad Pathway in Collecting Duct Cells
Título de la Revista: FRONTIERS IN PHARMACOLOGY
Volumen: 10
Editorial: FRONTIERS MEDIA SA
Fecha de publicación: 2019
Idioma: English
DOI:

10.3389/fphar.2019.00803

Notas: ISI