Rankin Gary O, Sweeney Adam, Racine Christopher, Ferguson Travis, Preston Deborah, Anestis Dianne K
Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, United States.
Department of Pharmacology, Physiology and Toxicology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, United States.
Chem Biol Interact. 2014 Oct 5;222:126-32. doi: 10.1016/j.cbi.2014.10.001. Epub 2014 Oct 19.
Chlorinated anilines are nephrotoxicants both in vivo and in vitro. The mechanism of chloroaniline nephrotoxicity may occur via more than one mechanism, but aminochlorophenol metabolites appear to contribute to the adverse in vivo effects. The purpose of this study was to compare the nephrotoxic potential of 4-aminophenol (4-AP), 4-amino-2-chlorophenol (4-A2CP), 4-amino-3-chlorophenol (4-A3CP) and 4-amino-2,6-dichlorophenol (4-A2,6DCP) using isolated renal cortical cells (IRCC) from male Fischer 344 rats as the model and to explore renal bioactivation mechanisms for 4-A2CP. For these studies, IRCC (∼4×10(6)cells/ml) were incubated with an aminophenol (0.5 or 1.0mM) or vehicle for 60min at 37°C with shaking. In some experiments, cells were pretreated with an antioxidant or cytochrome P450 (CYP), flavin-containing monooxygenase (FMO), peroxidase or cyclooxygenase inhibitor prior to 4-A2CP (1.0mM). Lactate dehydrogenase (LDH) release served as a measure of cytotoxicity. The order of decreasing nephrotoxic potential in IRCC was 4-A2,6-DCP>4-A2CP>4-AP>4-A3CP. The cytotoxicity induced by 4-A2CP was reduced by pretreatment with the peroxidase inhibitor mercaptosuccinic acid, and some antioxidants (ascorbate, glutathione, N-acetyl-l-cysteine) but not by others (α-tocopherol, DPPD). In addition, pretreatment with the iron chelator deferoxamine, several CYP inhibitors (except for the general CYP inhibitor piperonyl butoxide), FMO inhibitors or indomethacin (a cyclooxygenase inhibitor) failed to attenuate 4-A2CP cytotoxicity. These results demonstrate that the number and ring position of chloro groups can influence the nephrotoxic potential of 4-aminochlorophenols. In addition, 4-A2CP may be bioactivated by cyclooxygenase and peroxidases, and free radicals appear to play a role in 4-A2CP cytotoxicity.
氯代苯胺在体内和体外均为肾毒物。氯代苯胺肾毒性的机制可能通过多种途径发生，但氨基酚代谢产物似乎对体内不良影响有作用。本研究的目的是使用雄性Fischer 344大鼠的离体肾皮质细胞（IRCC）作为模型，比较4-氨基苯酚（4-AP）、4-氨基-2-氯苯酚（4-A2CP）、4-氨基-3-氯苯酚（4-A3CP）和4-氨基-2,6-二氯苯酚（4-A2,6DCP）的肾毒性潜力，并探索4-A2CP的肾脏生物活化机制。对于这些研究，将IRCC（约4×10⁶个细胞/ml）与氨基酚（0.5或1.0 mM）或溶剂在37°C下振荡孵育60分钟。在一些实验中，细胞在接触4-A2CP（1.0 mM）之前用抗氧化剂或细胞色素P450（CYP）、含黄素单加氧酶（FMO）、过氧化物酶或环氧化酶抑制剂进行预处理。乳酸脱氢酶（LDH）释放作为细胞毒性的指标。IRCC中肾毒性潜力降低的顺序为4-A2,6-DCP>4-A2CP>4-AP>4-A3CP。用抗过氧化物酶抑制剂巯基琥珀酸和一些抗氧化剂（抗坏血酸、谷胱甘肽、N-乙酰-L-半胱氨酸）预处理可降低4-A2CP诱导的细胞毒性，但其他抗氧化剂（α-生育酚、DPPD）则不能。此外，用铁螯合剂去铁胺、几种CYP抑制剂（除了通用的CYP抑制剂胡椒基丁醚）、FMO抑制剂或吲哚美辛（一种环氧化酶抑制剂）预处理未能减弱4-A2CP的细胞毒性。这些结果表明氯原子的数量和环位置可影响4-氨基氯苯酚的肾毒性潜力。此外，4-A2CP可能通过环氧化酶和过氧化物酶进行生物活化，并且自由基似乎在4-A2CP的细胞毒性中起作用。
