Oxidative stress is a triggering factor for LPS-induced Mrp2 internalization in the cryopreserved rat and human liver slices

• Published in: Biochemical and biophysical research communications Vol. 399; no. 2; pp. 279 - 285
• Main Authors: Sekine, Shuichi, Yano, Kentaro, Saeki, Junjiro, Hashimoto, Nozomi, Fuwa, Toru, Horie, Toshiharu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20-08-2010
• Subjects: Animals; Antioxidants - chemistry; Antioxidants - pharmacology; Cholestasis; Cholestasis - metabolism; Cryopreservation; Diketopiperazines - chemistry; Diketopiperazines - pharmacology; Dimerumic acid; Glutathione - metabolism; Humans; Hydroxamic Acids - chemistry; Hydroxamic Acids - pharmacology; Internalization; Lipopolysaccharides; Liver - drug effects; Liver - metabolism; Liver slice; Mrp2; Multidrug Resistance-Associated Proteins - metabolism; Oxidative Stress; Rats; Oxidative stress; NO; Mrp2; t-BHP; BSA/PBS; LPS; F-actin; Internalization; Liver slice; ROS; Dimerumic acid; DMA; GSH; Cholestasis
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2010.07.069

Cholestasis develops during inflammation and is characterized as occurring under oxidative stress. We have described the internalization of multidrug resistance-associated protein 2 (Mrp2), a biliary transporter involved in bile-salt-independent bile flow, under ethacrynic acid or lipopolysaccharide (LPS)-induced acute oxidative stress in rat liver. However, it remains unclear whether canalicular Mrp2 internalization is observed in human liver under conditions of acute oxidative stress. In this study, we examined the effect of dimerumic acid (DMA), an antioxidant and found in traditional Chinese medicine, on endotoxin-induced Mrp2 internalization in rat and human liver slices. At 1.5h following LPS treatment (100μg/mL), canalicular Mrp2 localization was disrupted without changing the expression of Mrp2 protein or the integrity of filamentous actin in the rat and human liver slices. Pretreatment with DMA (10μM) counteracted LPS-induced subcellular distribution of Mrp2. Our data clearly indicated that LPS-induced short-term rapid retrieval of Mrp2 from the canalicular surface resulted from LPS-induced oxidative stress in rat and human liver slices.
► MRP2 internalization is triggered by oxidative stress in humans. ► DMA can suppress the LPS-induced MRP2 internalization in humans. ► LPS-induced MRP2 internalization is not caused by the disruption of F-actin. ► The cryopreserved human liver is a useful model for experimental cholestasis.