Background: Although inflammation and apoptosis are known to play important roles in cisplatin nephrotoxicity, the exact intracellular signaling mechanisms are not well understood. Recent reports that extracellular signal-regulated kinase (ERK1/2) pathway mediates cisplatin-induced caspase activation and apoptosis in cultured renal tubular cells led us to investigate the effect of MAPK/ERK kinase (MEK) inhibitor, an immediate upstream of ERK1/2 in cisplatin-induced acute renal failure (ARF) in mice.
Methods: The effect of MEK/ERK1/2 inhibition on kidney tumor necrosis factor-alpha (TNF-alpha (gene expression, inflammation, the activation of tissue caspases, and apoptosis were examined in addition to its effects on renal function and histology in cisplatin-induced ARF in mice.
Results: Pretreatment of MEK inhibitor, U0126, decreased ERK1/2 phosphorylation following cisplatin administration with significant functional and histologic protection. This beneficial effect was accompanied by decrease in TNF-alpha gene expression level and inflammation, as well as in caspase 3 activity and apoptosis.
Conclusion: These data provide evidence that ERK1/2 pathway functions as an upstream signal for TNF-alpha-mediated inflammation and caspase 3-mediated apoptosis in cisplatin-induced ARF in mice and suggest that ERK1/2 can be a novel therapeutic target in cisplatin nephrotoxicity.