Cantoni Lavinia, Valaperta Rea, Ponsoda Xavier, Castell José V, Barelli Davide, Rizzardini Milena, Mangolini Alessandra, Hauri Lisa, Villa Pia
Laboratory of Molecular Pathology, Istituto di Ricerche Farmacologiche 'Mario Negri', Via Eritrea 62, 20157, Milan, Italy.
J Hepatol. 2003 Jun;38(6):776-83. doi: 10.1016/s0168-8278(03)00095-3.
BACKGROUND/AIMS: The role of oxidative stress in diclofenac hepatotoxicity is still not clear. This study examined whether the drug induced heme oxygenase-1 (HO-1), a stress protein.
HO-1 mRNA and HO activity were measured in mouse liver and in rat hepatocytes after treatment with diclofenac parallel to release of serum alanine aminotransferase (ALT) and sorbitol dehydrogenase (SDH) as a marker of hepatic damage.
HO-1 was transcriptionally and dose-dependently induced by diclofenac in mouse liver and rat hepatocytes. HO-1 mRNA, ALT and SDH peaked at the same time. Mechanistic studies revealed that the drug synergized with buthionine sulfoximine (BSO) in lowering hepatic glutathione, increased the formation of reactive oxygen intermediates and activated NF-kappaB and AP-1 in rat hepatocytes. HO-1 induction and hepatic damage were increased by BSO and only HO-1 induction was attenuated by the antioxidant N-acetylcysteine. HO-1 induction was also reduced by the cytochrome P-450 inhibitors ketoconazole and tranylcypromine, concomitantly with a significant decrease in the formation of diclofenac oxidative metabolites, which may give rise to reactive compounds.
Acute treatment with diclofenac induces HO-1 in rodent hepatocytes. Induction is influenced by changes in the cellular redox states and by cytochrome P-450 activity and gives a new insight into the response of the liver to diclofenac.
背景/目的：氧化应激在双氯芬酸肝毒性中的作用仍不明确。本研究检测了该药物是否诱导应激蛋白血红素加氧酶-1（HO-1）。
在用双氯芬酸处理小鼠肝脏和大鼠肝细胞后，检测HO-1 mRNA和HO活性，同时检测血清丙氨酸转氨酶（ALT）和山梨醇脱氢酶（SDH）的释放，作为肝损伤的标志物。
双氯芬酸在小鼠肝脏和大鼠肝细胞中以转录和剂量依赖的方式诱导HO-1。HO-1 mRNA、ALT和SDH同时达到峰值。机制研究表明，该药物与丁硫氨酸亚砜胺（BSO）协同降低肝脏谷胱甘肽水平，增加活性氧中间体的形成，并激活大鼠肝细胞中的NF-κB和AP-1。BSO增加了HO-1的诱导和肝损伤，而抗氧化剂N-乙酰半胱氨酸仅减弱了HO-1的诱导。细胞色素P-450抑制剂酮康唑和反苯环丙胺也降低了HO-1的诱导，同时双氯芬酸氧化代谢产物的形成显著减少，这些代谢产物可能产生反应性化合物。
双氯芬酸急性处理可诱导啮齿动物肝细胞中的HO-1。诱导受细胞氧化还原状态变化和细胞色素P-450活性的影响，为肝脏对双氯芬酸的反应提供了新的见解。
