2-Amino-5-chlorophenol Toxicity in Renal Cortical Slices from Fischer 344 Rats: Effect of Antioxidants and Sulfhydryl Agents

• Published in: Toxicology and applied pharmacology Vol. 161; no. 1; pp. 1 - 9
• Main Authors: Valentovic, Monica, Meadows, M.Kathleen, Harmon, R.Christopher, Ball, John G., Hong, Suk K., Rankin, Gary O.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15.11.1999; Elsevier
• Subjects: 2-amino-5-chlorophenol; Animals; Antioxidants - pharmacology; Ascorbic Acid - pharmacology; Biological and medical sciences; Buthionine Sulfoximine - pharmacology; Chemical and industrial products toxicology. Toxic occupational diseases; Chlorophenols - antagonists & inhibitors; Chlorophenols - toxicity; Deferoxamine - pharmacology; Dithiothreitol - pharmacology; Dose-Response Relationship, Drug; Free Radicals - metabolism; Gluconeogenesis - drug effects; Glutathione - metabolism; Glutathione - pharmacology; In Vitro Techniques; Iron - metabolism; Iron Chelating Agents - pharmacology; Kidney Cortex - drug effects; Kidney Cortex - metabolism; Lipid Peroxidation - drug effects; Male; Medical sciences; Phenylenediamines - pharmacology; Pyruvic Acid - metabolism; Rats; Rats, Inbred F344; Sulfhydryl Reagents - pharmacology; Toxicology; Various organic compounds; Oxidative stress; Urinary system disease; Rat; Toxicity; Rodentia; In vitro; Histological section; Free radical; Kidney; Vertebrata; Mammalia; Animal; Mechanism of action
• ISSN: 0041-008X; 1096-0333
• DOI: 10.1006/taap.1999.8784

2-Amino-5-chlorophenol is nephrotoxic through an unidentified mechanism. This study examined the in vitro toxicity of 2-amino-5-chlorophenol in renal cortical slices from Fischer 344 rats and specifically assessed induction of lipid peroxidation and depletion of renal glutathione. Renal cortical slices exposed to 0, 0.25, 0.5, and 1 mM 2-amino-5-chlorophenol exhibited a concentration- and time-dependent increase in lactate dehydrogenase (LDH) leakage. Pyruvate-directed gluconeogenesis was diminished in a concentration-dependent manner following a 90-min incubation with 0, 0.25, 0.5, and 1 mM 2-amino-5-chlorophenol. Lipid peroxidation was induced within 60 min by 1 mM 2-amino-5-chlorophenol in renal slices relative to control tissue. Total glutathione (GSH) levels were decreased below control values within 30 min of exposure to 0.5 and 1 mM 2-amino-5-chlorophenol. These results indicated that GSH levels were decreased prior to the appearance of increased LDH leakage and diminished membrane integrity. 2-Amino-5-chlorophenol toxicity was increased in renal slices isolated from animals pretreated with buthionine sulfoximine (BSO, 890 mg/kg ip). Pretreatment of renal slices with the phenolic antioxidant N,N′-diphenyl-1,4-phenylenediamine (DPPD, 50 μM) or the iron chelator deferoxamine did not reduce 2-amino-5-chlorophenol cytotoxicity. These results suggest that 2-amino-5-chlorophenol toxicity was not mediated through an iron-dependent mechanism. 2-Amino-5-chlorophenol cytotoxicity was reduced by a 15-min pre-incubation with 2 mM ascorbate or a 30-min preincubation with the thiol-containing agents GSH (1 mM) or dithiothreitol (1 mM, DTT). Pretreatment with GSH, DTT, or ascorbate reduced LDH leakage and lipid peroxide generation induced by 2-amino-5-chlorophenol. These results suggest that 2-amino-5-chlorophenol cytotoxicity involved free radical generation through an iron-independent mechanism. Toxicity was reduced by the presence of the antioxidant ascorbate or by addition of glutathione.