ABSTRACT
<p><b>OBJECTIVE</b>To explore the effect of p38MAPK signaling pathway in interleukin-18-induced transdifferentiation in renal proximal tubular cells.</p><p><b>METHODS</b>Human proximal tubular epithelial cell line (HK-2 cells) was cultured in vitro. After preincubated with SB203580 (0, 5, 10, 20 micromol/L) for 30 minutes, cells were exposed to IL-18 (100 ng/ml) for 24, 48 and 72 hours respectively. The expressions of a-smooth actin (alpha-SMA) in cultured HK-2 cells were assessed by RT-PCR and ELISA.</p><p><b>RESULTS</b>IL-18-induced expressions of a-SMA mRNA and protein were inhibited obviously by a dose-dependent manner when HK-2 cells were incubated with SB203580 (0, 5, 10, 20 micromol/L) and IL-18 (100 ng/ml) for different time (P < 0.05).</p><p><b>CONCLUSION</b>IL-18-induced transdifferentiation of renal tubular epithelial cells (RTECs) is suppressed obviously by blocking p38MAPK signaling pathways. IL-18-induced transdifferentiation of RTECs is probably mediated, at least in part, through the activation of p38MAPK signaling pathways.</p>