Polymyxin B Nephrotoxicity: From Organ to Cell Damage

• Published in: PloS one Vol. 11; no. 8; p. e0161057
• Main Authors: Vattimo, Maria de Fátima Fernandes, Watanabe, Mirian, da Fonseca, Cassiane Dezoti, Neiva, Luciana Barros de Moura, Pessoa, Edson Andrade, Borges, Fernanda Teixeira
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.08.2016; Public Library of Science (PLoS)
• Subjects: Animals; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - toxicity; Apoptosis; Apoptosis - drug effects; Biology and Life Sciences; Cell Survival - drug effects; Clinical medicine; Complications and side effects; Creatinine; Cytochrome; Cytochrome c; Cytochromes c - metabolism; Cytotoxicity; Damage assessment; Damage localization; Dehydrogenase; Dosage and administration; Drug dosages; Electron microscopy; Hemodynamics; Ischemia; Kidney - drug effects; Kidney - metabolism; Kidney - pathology; Kidneys; L-Lactate dehydrogenase; L-Lactate Dehydrogenase - metabolism; Laboratory animals; Lactate dehydrogenase; Lactic acid; LLC-PK1 Cells; Localization; Lymphocytes B; Male; Medicine and Health Sciences; Metabolism; Microscopy, Electron, Transmission; Mitochondria; Mitochondria - drug effects; Mitochondria - metabolism; Mitochondria - pathology; Mitochondrial diseases; Necrosis; Nephrology; Nitric oxide; Nitric Oxide - metabolism; Nursing schools; Oxidation resistance; Oxidative stress; Oxidative Stress - drug effects; Polymyxin B; Polymyxin B - pharmacokinetics; Polymyxin B - toxicity; Polymyxins; Position (location); Rats; Rats, Wistar; Renal cortex; Renal function; Research and Analysis Methods; Rhodamine; Risk factors; Rodents; Side effects; Sodium chloride; Structural integrity; Swine; Toxicity; Urine; Veins & arteries; Brazil
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0161057

Polymyxins have a long history of dose-limiting toxicity, but the underlying mechanism of polymyxin B-induced nephrotoxicity is unclear. This study investigated the link between the nephrotoxic effects of polymyxin B on renal metabolic functions and mitochondrial morphology in rats and on the structural integrity of LLC-PK1 cells. Fifteen Wistar rats were divided into two groups: Saline group, rats received 3 mL/kg of 0.9% NaCl intraperitoneally (i.p.) once a day for 5 days; Polymyxin B group, rats received 4 mg/kg/day of polymyxin B i.p. once a day for 5 days. Renal function, renal hemodynamics, oxidative stress, mitochondrial injury and histological characteristics were assessed. Cell membrane damage was evaluated via lactate dehydrogenase and nitric oxide levels, cell viability, and apoptosis in cells exposed to 12.5 μM, 75 μM and 375 μM polymyxin B. Polymyxin B was immunolocated using Lissamine rhodamine-polymyxin B in LLC-PK1 cells. Polymyxin B administration in rats reduced creatinine clearance and increased renal vascular resistance and oxidative damage. Mitochondrial damage was confirmed by electron microscopy and cytosolic localization of cytochrome c. Histological analysis revealed tubular dilatation and necrosis in the renal cortex. The reduction in cell viability and the increase in apoptosis, lactate dehydrogenase levels and nitric oxide levels confirmed the cytotoxicity of polymyxin B. The incubation of LLC-PK1 cells resulted in mitochondrial localization of polymyxin B. This study demonstrates that polymyxin B nephrotoxicity is characterized by mitochondrial dysfunction and free radical generation in both LLC-PK1 cells and rat kidneys. These data also provide support for clinical studies on the side effects of polymyxin B.