First Author | Chen WC | Year | 2015 |
Journal | Am J Pathol | Volume | 185 |
Issue | 9 | Pages | 2468-81 |
PubMed ID | 26212907 | Mgi Jnum | J:226519 |
Mgi Id | MGI:5697619 | Doi | 10.1016/j.ajpath.2015.05.019 |
Citation | Chen WC, et al. (2015) Matrix-Stiffness-Regulated Inverse Expression of Kruppel-Like Factor 5 and Kruppel-Like Factor 4 in the Pathogenesis of Renal Fibrosis. Am J Pathol 185(9):2468-81 |
abstractText | The proliferation of mouse proximal tubular epithelial cells in ex vivo culture depends on matrix stiffness. Combined analysis of the microarray and experimental data revealed that Kruppel-like factor (Klf)5 was the most up-regulated transcription factor accompanied by the down-regulation of Klf4 when cells were on stiff matrix. These changes were reversed by soft matrix via extracellular signal-regulated kinase (ERK) inactivation. Knockdown of Klf5 or forced expression of Klf4 inhibited stiff matrix-induced cell spreading and proliferation, suggesting that Klf5/Klf4 act as positive and negative regulators, respectively. Moreover, stiff matrix-activated ERK increased the protein level and nuclear translocation of mechanosensitive Yes-associated protein 1 (YAP1), which is reported to prevent Klf5 degradation. Finally, in vivo model of unilateral ureteral obstruction revealed that matrix stiffness-regulated Klf5/Klf4 is related to the pathogenesis of renal fibrosis. In the dilated tubules of obstructed kidney, ERK/YAP1/Klf5/cyclin D1 axis was up-regulated and Klf4 was down-regulated. Inhibition of collagen crosslinking by lysyl oxidase inhibitor alleviated unilateral ureteral obstruction-induced tubular dilatation and proliferation, preserved Klf4, and suppressed the ERK/YAP1/Klf5/cyclin D1 axis. This study unravels a novel mechanism how matrix stiffness regulates cellular proliferation and highlights the importance of matrix stiffness-modulated Klf5/Klf4 in the regulation of renal physiologic functions and fibrosis progression. |