抄録
The need for development of non-animal in vitro test methods has emerged in order to obtain target organ-specific and mechanism-derived information after exposure to toxins. In particular, in vitro methods for assessment of kidney toxicity have become an invaluable tool due to the target organ-selective nature of many nephrotoxic xenobiotics. Although rat kidney cells have shown promise, cells from human tissue can provide more reliable information for toxicological risk evaluation in humans. In vitro nephrotoxicity assessment using in vivo biomarkers in human cell lines has not been well established to date. The present study investigated the potential use of biomarkers for cisplatin-induced nephrotoxicity assessment in vitro using HK-2 cells derived from human kidney proximal tubule epithelial cells. Among the biomarkers known to be increased by renal toxicity, kidney injury molecule (KIM)-1, calbindin and TIMP-1 were significantly increased in conditioned media at treatment of HK-2 cells with cisplatin. The mRNA levels of KIM-1, calbindin and TIMP-1 were also increased by cisplatin, indicating that cisplatin-induced up-regulation involves transcriptional activation. The expression levels of KIM-1 and calbindin were significantly increased in urine of cisplatin-treated rats, providing in vivo validation of the in vitro results. Taken together, we demonstrate that the nephrotoxic biomarkers, KIM-1, calbindin and TIMP-1 can be effectively used as in vitro biomarkers for cisplatin-induced nephrotoxicity using a HK-2 human kidney cell system.
