Kidney toxicity in miR-155-/- mice

The development of nephrotoxicity limits the maximum achievable dosage and treatment intervals for cisplatin chemotherapy. Therefore, identifying mechanisms that regulate this toxicity could offer novel methods to optimize cisplatin delivery. MicroRNAs are capable of regulating many different genes, and can influence diverse cellular processes, including cell death and apoptosis. We previously observed miR-155 to be highly increased following ischemic or toxic injury to the kidneys and, therefore, sought to determine whether mice deficient in miR-155 would respond differently to kidney injury. miR-155-/- mice (B6.Cg-Mir155tm1.1Rsky/J originally purchased from The Jackson Laboratory) and age- and weight-matched C57BL/6 (wild type) mice (Charles River Laboratories) were used in this study. Mice were injected with one single 20mg/kg dose of cisplatin. Kidney tissues were collected at 0, 24, 48, and 72 hours i.p. with saline-injected mice as control. Total RNA extracted from the kidney tissues were used for gene expression analysis with Agilent Mouse whole genome 4x44k v2 array.