Figure 5.

LXR agonist suppresses HG-induced OPN expression in proximal tubular epithelial cells. mProx24 cells, a mouse renal proximal tubular epithelial cell line, were pretreated for 24 h with vehicle (DMSO) or the indicated concentrations of the synthetic LXR agonist T0901317. (A) After stimulation for 24 h with high-glucose (HG) medium (25 mM), total RNA was isolated from mProx24 cells and analyzed for the OPN mRNA expression levels by qRT-PCR. Quantification was performed by densitometry, with normalization by the cohybridized GAPDH mRNA expression levels. Data are means ± SEM. *P<0.05. (B) After 24 h, OPN protein expression was analyzed by Western blotting. Full-length OPN as well as the C-terminal fragment of MMP-cleaved OPN are significantly upregulated by HG stimulation, and they are suppressed by pretreatment with T0901317. Quantification was performed by densitometry of three independently performed experiments, with normalization by β-actin. Data are means ± SEM. *P<0.05.