Role of Oxidative Stress in Lithium-Induced Nephropathy

Long-term lithium treatment was associated with chronic kidney disease and renal failure although the underlying pathogenic mechanisms are not certainty known. The aim of this study was to evaluate changes in oxidative stress measures as well as renal functional and structural alterations associated with chronic use of lithium in rats. Forty Wistar male rats were randomized into four groups: control groups fed ad libitum powered standard diet for 1 and 3 months and experimental groups fed ad libitum the same diet supplemented with 60 mmol/kg diet for 1 and 3 months. Histopathological changes, laboratory parameters, and oxidative stress measurements were assessed at months 1 and 3. The experimental animals showed alteration of the cortical tubules from the first month of lithium-treatment and a decrease in the glomerular filtration rate and in the glomerular area at the third month. There was an increase in thiobarbituric acid reactive substances and carbonyls, as well as an increase in reduced glutathione, in the kidney of rats exposed to lithium. These changes were evident from the first month of treatment and remained throughout the experiment. Our results suggest that, oxidative stress could be one of the pathogenic mechanisms involved in the structural and functional alterations of the kidney associated with prolonged use of lithium. The study of the pathogenic mechanisms involved in lithium-induced nephropathy is a critical issue for the development of new strategies for prevention and/or early detection.