Time course of lipid peroxidation in puromycin aminonucleoside-induced nephropathy

Abstract

Reactive oxygen species have been implicated in the pathogenesis of acute puromycin aminonucleoside (PAN)-induced nephropathy, with antioxidants significantly reducing the proteinuria. The temporal relationship between lipid peroxidation in the kidney and proteinuria was examined in this study. Rats were treated with a single IV injection of puromycin aminonucleoside, (PAN, 7.5 mg/kg) and 24 hour urine samples were obtained prior to sacrifice on days 3,5,7,10,17,27,41 (N = 5-10 per group). The kidneys were removed, flushed with ice cold TRIS buffer. Kidney cortices from each animal were used to prepare homogenates. Tissue lipid peroxidation was measured in whole homogenates as well as in lipid extracts from homogenates as thiobarbituric acid reactive substances. Proteinuria was evident at day 5, peaked at day 7 and persisted to day 27. Lipid peroxidation in homogenates was maximal at day 3 and declined rapidly to control levels by day 17. This study supports the role of lipid peroxidation in mediating the proteinuric injury in PAN nephropathy.