25 Renal hL-FABP binds to lipid peroxidation MLN0128 chemical structure products generated by oxidative stress, and redistributes them into the tubular lumen, thereby preventing tubulointerstitial damage. Cisplatin is a platinum-based chemotherapy drug used to treat various types of cancers, including sarcomas and some carcinomas. However, acute kidney injury is a serious side effect of cisplatin, thus, strategies to reduce acute kidney injury is important for continuation of cisplatin as a cancer treatment modality. This model is used to evaluate the pathophysiology of AKI after platinum-based chemotherapy. Intraperitoneal

injection of cisplatin in mice induces acute tubular necrosis and apoptosis, which are similar to the phenotypes observed in human cisplatin induced nephropathy. In the proximal tubules of this model, it was reported that metabolism of intracellular FFA was suppressed and nonesterified fatty acid and triglycerides accumulated

in kidney tissue. When the metabolism of FFA is activated by activation of the peroxisome proliferator-activated receptor (PPAR), the degree of cisplatin induced nephropathy is attenuated, therefore, increased intracellular FFA is considered to be closely associated with the generation and progression of nephropathy. Since there is a PPAR response element (PPRE) in the promoter region of hL-FABP, the presence of PPAR ligand, which activates PPAR, upregulates the expression of hL-FABP as well.30 In the cisplatin-induced nephropathy model, gene and protein expressions DAPT of hL-FABP are upregulated and urinary excretion of hL-FABP is also increased.26,27 Although the degree of tubulointerstitial

damage in the Tg mice is similar to those in the WT mice, accumulation of FFA in the kidney of Tg Lepirudin mice is significantly inhibited and acute kidney injury in the Tg mice is significantly reduced by administration of PPAR ligand, which further upregulates the expression of renal hL-FABP. Further, urinary hL-FABP levels are decreased in the Tg mice administered both cisplatin and PPAR as compared to the Tg mice with cisplatin administration alone. From these results, it is concluded that more upregulation of renal hL-FABP by PPAR activation is protective of acute kidney injury in this model. Adenine is one of the two purine bases used in the formation of DNA and RNA. Adenine injected into the body is oxidized to 2,8-dihydroxyadenine (DHA) by xanthine dehydrogenase (XDH). Since DHA has low solubility in body fluid, injection of a large amount of adenine causes DHA to be filtered through the glomeruli and to accumulate in the tubular lumen, thereby leading to tubulointerstitial inflammation and subsequent tubulointerstitial fibrosis. XDH inhibitors, such as allopurinol, inhibit the production of DHA derived from adenine and attenuate adenine-induced nephropathy.