酮康唑对斯普拉格-道利大鼠的肝毒性：谷胱甘肽耗竭、含黄素单加氧酶介导的生物活化及肝脏共价结合

Hepatotoxicity of ketoconazole in Sprague-Dawley rats: glutathione depletion, flavin-containing monooxygenases-mediated bioactivation and hepatic covalent binding.

Rodriguez R J, Buckholz C J

Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97331-3507, USA.

Xenobiotica. 2003 Apr;33(4):429-41. doi: 10.1080/0049825031000072243.

Abstract

This study has examined ketoconazole (KT)-induced hepatotoxicity in vivo and in vitro, using male Sprague-Dawley rats with [(3)H]KT (1.5 micro Ci mg(-1)) at 40 and 90 mg KT kg(-1) doses. Blood and liver samples were collected from 0 to 24 h for alanine aminotransaminase (ALT), glutathione (GSH) and covalent binding analyses. 2. Covalent binding occurred as early as 0.5 h, peaked at 2 h (0.026 +/- 0.01 nmol KT mg(-1) protein) and 8 h (0.088 +/- 0.04 nmol KT mg(-1) protein) for 40 and 90 mg KT kg(-1) doses, respectively. ALT levels increased at 0.5 h for the 40 and 90 mg KT kg(-1) doses (44.3 and 56.4 U ml(-1), respectively) relative to control, 22.7 U ml(-1). At 24 h, the 90 mg KT kg(-1) dose reduced hepatic GSH levels from 9.92 +/- 1.1 to 4.76 +/- 0.3 nmol GSH mg(-1) protein. 3. The role of the flavin-containing monooxygenases (FMO) utilized Sprague-Dawley microsomes with 1, 10 and 100 micro M [(3)H]KT. Maximum covalent binding occurring at 100 micro M KT. Heat inactivation of microsomal FMO significantly decreased covalent binding by 75%, whereas 1 mM GSH significantly reduced covalent binding by 65%. 4. Thus, KT-induced hepatotoxicity is dose- and time-dependent and appears to be FMO mediated, in part, to metabolites that may react with protein and, possibly, GSH.

摘要

本研究在体内和体外检测了酮康唑（KT）诱导的肝毒性，使用雄性Sprague-Dawley大鼠，分别给予40和90 mg KT kg⁻¹剂量的[(³)H]KT（1.5微居里毫克⁻¹）。在0至24小时收集血液和肝脏样本，用于丙氨酸转氨酶（ALT）、谷胱甘肽（GSH）和共价结合分析。2. 共价结合最早在0.5小时出现，40和90 mg KT kg⁻¹剂量分别在2小时（0.026±0.01 nmol KT毫克⁻¹蛋白质）和8小时（0.088±0.04 nmol KT毫克⁻¹蛋白质）达到峰值。相对于对照组（22.7 U ml⁻¹），40和90 mg KT kg⁻¹剂量在0.5小时时ALT水平升高（分别为44.3和56.4 U ml⁻¹）。在24小时时，90 mg KT kg⁻¹剂量使肝脏GSH水平从9.92±1.1降至4.76±0.3 nmol GSH毫克⁻¹蛋白质。3. 利用含有黄素的单加氧酶（FMO）的作用，使用含1、10和100微摩尔[(³)H]KT的Sprague-Dawley微粒体。最大共价结合发生在100微摩尔KT时。微粒体FMO的热失活显著降低共价结合75%，而1毫摩尔GSH显著降低共价结合65%。4. 因此，KT诱导的肝毒性是剂量和时间依赖性的，并且似乎部分由FMO介导，形成可能与蛋白质以及可能与GSH反应的代谢产物。