Calcium citrate improves the epithelial-to-mesenchymal transition induced by acidosis in proximal tubular cells.

Abstract

INTRODUCTION:

Epithelial-to-mesenchymal transition (EMT) is a key event in renal fibrosis. The aims of the study were to evaluate acidosis induced EMT, transforming-growth-factor (TGF) β1 role and citrate effect on it.

METHODS:

HK2 cells (ATCC 2290) were cultured in DMEM/HAM F12 medium, pH 7.4. At 80% confluence, after 24 hr under serum free conditions, cells were distributed in three groups (24 hours): A) Control: pH 7.4, B) Acidosis: pH 7.0 and C) Calcium citrate (0.2 mmol/L) + pH 7.0. Change (Δ) of intracellular calcium concentration, basal and after Angiotensin II (10-6M) exposition, were measured to evaluate cellular performance. EMT was evaluated by the expression of α-smooth muscle actin (α-SMA) and E-cadherin by immunocytochemistry and/or Western blot. TGF-β1 secretion was determined by ELISA in cell supernatant.

RESULTS:

At pH 7.0 HK2 cells significantly reduced E-cadherin and increased α-SMA expression (EMT). Supernatant TGF-β1 levels were higher than in control group. Calcium citrate decreased acidosis induced EMT and improved cells performance, without reduction of TGF-β production.

CONCLUSIONS:

Acidosis induces EMT and secretion of TGF-β1 in tubular proximal cells in culture and citrate improves cellular performance and ameliorates acidosis induced EMT.

• Authors: Maria José Rodriguez Cabalgante, Liliana Gadola, Leonella Luzardo, María Márquez, José Boggia, Mirian Aparecida Boim
• Journal: Jornal brasileiro de nefrologia : 'orgao oficial de Sociedades Brasileira e Latino-Americana de Nefrologia (J Bras Nefrol) 2012 Oct-Dec Vol. 34 Issue 4 Pg. 343-8 ISSN: 2175-8239 [Electronic] Brazil
• PMID: 23318822 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Calcium Citrate

Topics

• Acidosis, Renal Tubular (drug therapy, pathology)
• Calcium Citrate (pharmacology, therapeutic use)
• Cells, Cultured
• Epithelial-Mesenchymal Transition (drug effects)
• Humans
• Kidney Tubules, Proximal (cytology, drug effects)