These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Albumin-induced epithelial mesenchymal transformation.
    Author: Ibrini J, Fadel S, Chana RS, Brunskill N, Wagner B, Johnson TS, El Nahas AM.
    Journal: Nephron Exp Nephrol; 2012; 120(3):e91-102. PubMed ID: 22613868.
    Abstract:
    BACKGROUND: Progressive chronic kidney disease is often associated with albuminuria and renal fibrosis linked to the accumulation of myofibroblasts producing extracellular matrix. Renal myofibroblasts are derived from a number of cells including tubular epithelial cells (TECs) through epithelial mesenchymal transformation (EMT). This study explores the hypothesis that exposure of TECs to albumin induces EMT. METHODS: Normal rat TECs (NRK52E) were exposed in culture to de-lipidated bovine serum albumin (dBSA; 10 mg/ml) for 2, 4 and 6 days. Binding/uptake of fluoresceined albumin by PTCs was evaluated. Transformation into myofibroblasts was assessed by light and electron microscopy, immunofluorescence and Western blotting for α-smooth muscle actin (α-SMA), E-cadherin and transforming growth factor-β1 (TGF-β1). We also investigated the expression of fibroblast-specific protein-1 (FSP-1) and collagens I, III and IV. TGF-β1 biological activity, mRNA and protein were measured. A neutralising anti-TGF-β1 antibody was used to analyse the role of TGF-β1 in albumin-induced EMT. RESULTS: Exposure of TECs to dBSA led to binding/uptake of albumin as well as fibroblastic morphological changes. Incubation of TECs with dBSA caused a reduction of TEC marker E-cadherin (ANOVA p = 0.0002) and de novo expression of fibroblast markers α-SMA and FSP-1 (ANOVA p = 0.0001) in a time-dependent manner. It also increased expression and activity of TGF-β1. Neutralisation of TGF-β1 significantly reduced EMT (p < 0.01). CONCLUSION: This study demonstrates that in vitro, albumin induces the transformation of TECs into cells with myofibroblast characteristics; a process that may be TGF-β1 dependent.
    [Abstract] [Full Text] [Related] [New Search]