Kidney Res Clin Pract.  2015 Jun;34(2):83-92. 10.1016/j.krcp.2015.03.005.

Effect of aldosterone on epithelial-to-mesenchymal transition of human peritoneal mesothelial cells

• Yu M
• Shin HS
• Lee HK
• Ryu DR
• Kim SJ
• Choi KB
• Kang DH

• KMID: 2381522
• DOI: http://doi.org/10.1016/j.krcp.2015.03.005

Abstract

BACKGROUND
Peritoneal fibrosis is one of the major causes of technical failure in patients on peritoneal dialysis. Epithelial-to-mesenchymal transition (EMT) of the peritoneum is an early and reversible mechanism of peritoneal fibrosis. Human peritoneal mesothelial cells (HPMCs) have their own renin-angiotensin-aldosterone system (RAAS), however, it has not been investigated whether aldosterone, an end-product of the RAAS, induces EMT in HPMCs, and which mechanisms are responsible for aldosterone-induced EMT.
METHODS
EMT of HPMCs was evaluated by comparing the expression of epithelial cell marker, E-cadherin, and mesenchymal cell marker, alpha-smooth muscle actin after stimulation with aldosterone (1-100nM) or spironolactone. Activation of extracellular signal-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) and generation of reactive oxygen species (ROS) were assessed by western blotting and 2',7'-dichlorofluororescein diacetate staining, respectively. The effects of MAPK inhibitors or antioxidants (N-acetyl cysteine, apocynin, and rotenone) on aldosterone-induced EMT were evaluated.
RESULTS
Aldosterone induced EMT in cultured HPMCs, and spironolactone blocked aldosterone-induced EMT. Aldosterone induced activation of both ERK1/2 and p38 MAPK from 1 hour. Either PD98059, an inhibitor of ERK1/2, or SB20358, an inhibitor of p38 MAPK, attenuated aldosterone-induced EMT. Aldosterone induced ROS in HPMCs from 5 minutes, and antioxidant treatment ameliorated aldosterone-induced EMT. N-acetyl cysteine and apocynin alleviated activation of ERK and p38 MAPK.
CONCLUSION
Aldosterone induced EMT in HPMCs by acting through the mineralocorticoid receptor. Aldosterone-induced generation of ROS followed by activation of ERK, and p38 MAPK served as one of the mechanisms of aldosterone-induced EMT of HPMCs.

Keyword

Aldosterone; Epithelial-to-mesenchymal transition; Mesothelial cell; Peritoneal dialysis; Peritoneal fibrosis

MeSH Terms

Actins
Aldosterone*
Antioxidants
Blotting, Western
Cadherins
Cysteine
Epithelial Cells
Humans
p38 Mitogen-Activated Protein Kinases
Peritoneal Dialysis
Peritoneal Fibrosis
Peritoneum
Phosphotransferases
Protein Kinases
Reactive Oxygen Species
Receptors, Mineralocorticoid
Renin-Angiotensin System
Spironolactone
Actins
Aldosterone
Antioxidants
Cadherins
Cysteine
Phosphotransferases
Protein Kinases
Reactive Oxygen Species
Receptors, Mineralocorticoid
Spironolactone
p38 Mitogen-Activated Protein Kinases