Gremlin Activates the Smad Pathway Linked to Epithelial Mesenchymal Transdifferentiation in Cultured Tubular Epithelial Cells
Figure 6
(a) Gremlin increased TGF-β production. HK2 cells were stimulated with Gremlin (50 ng/mL) for 24 and 48 hours in serum-free medium. TGF-β1 protein levels were measured in the cell-conditioned medium using a specific ELISA. Data are expressed as mean ± SEM of 6 independent experiments. * versus control. (b) The late increase in gene expression of profibrotic factors caused by Gremlin is mediated by endogenous TGF-β production. HK2 cells were stimulated with Gremlin (50 ng/mL) for 24 hours in serum-free medium. TGF-β was blocked or not (control) by pretreatment of cells for 1 hour with an anti-TGF-β neutralizing antibody. Total cell RNA was isolated to assess mRNA levels by real-time PCR. Data are expressed as n-fold over control (considered as 1), as the mean ± SEM of 3 experiments. * versus control. # versus Gremlin.
