Involvement of Indoxyl Sulfate in Renal and Central Nervous System Toxicities During Cisplatin-induced Acute Renal Failure

Purpose The purpose of the present study was to explore the involvement of indoxyl sulfate (IS) in nephrotoxicity and central nervous system (CNS) toxicity in cisplatin (CDDP)-treated rats. Materials and Methods Renal function was evaluated by serum creatinine and BUN levels. The IS levels in the serum, brain and kidney was monitored by high-performance liquid chromatography method. Body weight and rectal temperature were monitored. Real-time PCR analysis was performed to examine rPer2 mRNA expression. Results Renal function deteriorated in a time-dependent manner after administration of CDDP. The concentration of IS in the serum, brain and kidney markedly increased 24–84 h after commencement of CDDP treatment. The observed increase in the levels of serum creatinine, BUN and IS was suppressed by concomitant administration of AST-120. Rectal temperature was significantly lowered 72–92 h after CDDP-treatment, which was partially restored by coadministration of AST-120. Moreover, the amplitude of rectal temperature rhythms was disrupted by treatment with CDDP. Circadian rhythm of rPer2 mRNA expression, a clock gene, in suprachiasmatic nucleus (SCN) and kidney was disturbed in CDDP-treated rats. Conclusions An increase in the IS level and the associated disturbance to the circadian rhythm are involved in the renal and CNS toxicities in CDDP-treatment. K.I. and H.W. contributed equally to this work.