| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1226222 | Journal of Proteomics | 2013 | 11 Pages |
Hyperoxaluria is one of etiologic factors of calcium oxalate kidney stone disease. However, response of renal tubular cells to high-oxalate environment remained largely unknown. We applied a gel-based proteomics approach to characterize changes in cellular proteome of MDCK cells induced by 10 mM sodium oxalate. A total of 14 proteins were detected as differentially expressed proteins. The oxalate-induced up-regulation of alpha-enolase in whole cell lysate was confirmed by 2-D Western blot analysis. Interaction network analysis revealed that cellular adaptive response under high-oxalate condition involved stress response, energy production, metabolism and transcriptional regulation. Down-regulation of RhoA, which was predicted to be associated with the identified proteins, was confirmed by immunoblotting. In addition, the up-regulation of alpha-enolase on apical surface of renal tubular epithelial cells was also confirmed by immunoblotting of the isolated apical membranes and immunofluorescence study. Interestingly, blockage of alpha-enolase expressed on the cell surface by antibody neutralization significantly reduced the number of calcium oxalate monohydrate (COM) crystals adhered on the cells. These results strongly suggest that surface alpha-enolase plays an important role as the enhancer of COM crystal binding. The increase of alpha-enolase expressed on the cell surface may aggravate kidney stone formation in patients with hyperoxaluria.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (352 K)Download as PowerPoint slideHighlights► Oxalate increased apical surface expression of alpha-enolase on renal tubular cells. ► Neutralization of surface alpha-enolase significantly reduced crystal adhesion. ► Surface alpha-enolase played crucial role as the enhancer of COM crystal binding. ► Increased surface alpha-enolase might induce kidney stone disease in hyperoxaluria.
