| Calculus Bovis Sativus (also referred to as in-vitro Cultured Calculus Bovis, CBS), an artificial substitute of natural Calculus Bovis (Niuhuang in Chinese, a traditional Chinese medicine), has been widely used to relieve fever, diminish inflammation and normalize function of gallbladder in last decade. This study aims to investigate the effects and possible mechanisms of CBS on α-naphthylisothiocyanate (ANIT)-induced intrahepatic cholestasis in rats. CBS (50,100or200mg/kg per day) was intragastrically (i. g.) given to experimental rats for seven consecutive days. A single dose of ANIT (100mg/kg i. g.) was given to rats at fifth day to induce intrahepatic cholestasis. The bile duct was cannulated with a PE10polyethylene tube to collect bile for2hours and bile flow was calculated by the weight of each specimen. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkalinephosphatase (ALP) and total bilirubin (TBIL) were determined by biochemical methods. Moreover, the mechanism of Calculus Bovis Sativus was elucidated by determining liver malondialdehyde (MDA) content and superoxide dismutase (SOD) activity. The biochemical observations were supplemented by histopathological examinations. Our results showed that CBS (50,100or200mg/kg) significantly prevented ANIT-induced changes in bile flow, and serum levels of ALT, AST, ALP and TBIL. Furthermore, CBS (50,100or200mg/kg) significantly reduced the elevated hepatic MDA content induced by ANIT and increased the hepatic SOD activity suppressed by ANIT. Accordingly, histopathology of the liver tissue showed that pathological injuries were relieved after CBS (100or200mg/kg) pretreatment. In conclusions, CBS exerted a protective effect on ANIT-induced intrahepatic cholestasis in rats, which may result from the attenuated oxidative damage and neutrophil infiltration in liver tissues.Calculus Bovis Sativus (CBS), an artificial substitute of Calculus Bovis (Niuhuang in Chinese, a traditional Chinese medicine), shares similar pharmacological effect with Calculus Bovis like relieving hepatobiliary diseases. However, the mechanisms involved are still unknown. This study aims to investigate the effect of CBS on17a-ethynylestradiol (EE)-induced cholestasis in the rat. CBS (50or150mg/kg per day) was intragastrically (i. g.) given to experimental rats for5consecutive days in coadministration with EE. At sixth day, the bile flow in2h was measured. The levels of serum biomarkers, hepatic MDA content and SOD activity were determined by biochemical methods. The histopathology of the liver tissue was evaluated. CBS (50or150mg/kg) significantly prevented EE-induced increases in serum levels of ALT, AST, ALP and TBIL. Decreased bile flow by EE was also restored with CBS treatment. Histopathology of the liver tissue showed that tissue lesions were relieved after CBS (50or150mg/kg) treatment. Besides, CBS (50or150mg/kg) significantly reduced the elevated hepatic MDA content induced by EE and increased the hepatic SOD activity suppressed by EE. In conclusions, CBS exerted a protective effect on EE-induced intrahepatic cholestasis in rats, which may result from the attenuated oxidative damage and tissue damage in liver tissues.Calculus Bovis Sativus (CBS) shares similar pharmacological effect with Calculus Bovis like relieving hepatobiliary diseases. However, the mechanisms involved are still unknown. This study aims to investigate the effect of CBS on17α-ethynylestradiol (EE)-induced cholestasis in the rat. CBS (50or150mg/kg per day) was intragastrically (i. g.) given to experimental rats for5consecutive days in coadministration with EE. At sixth day, the rats were sacrificed and the liver tissues were taken for examination. The expression of transporter was studied by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and western blot. Western blot studies indicated that EE significantly decreased the expression of Mrp2and Bcrp protein compared with control group. CBS (50or150mg/kg per day) treatment significantly increased the expression of Mrp2and Bcrp protein compared with EE group. RT-qPCR studies indicated that down-regulation of Bcrp by EE was at transcriptional level. CBS up-regulated the expression of Mrp2and Bcrp mRNA compared with EE group. PDZK1expression was downregulated in EE-treated rats. CBS significantly increased the expression of PDZK1mRNA and protein compared with EE only group. On the other hand, EE treatment significantly increased the expression of ERa protein. And CBS treatmnent significantly reduced the expression of ERa protein compared with EE group. In conclusion, CBS exerted a beneficial effect on EE-induced cholestasis in the rat, which may result from its induction of Mrp2and Bcrp expression.Baicalin is a major bioactive component of Scutellaria baicalensis Georgi (Lamiaceae) and a substrate of multiple drug resistance associated protein2(Mrp2). Mrp2mediates the bile excretion of baicalin from hepatocyte. Expression of hepatici Mrp2is downregulated in cholestasis. The aim of this study was to explore whether Calculus Bovis Sativus (CBS) treatment could influence the bile excretion of baicalin in ANIT-induced intrahepatic cholestasis. Mitoxantrone is an anti-tumor drug used to treat multiple cancers including breast cancer, acute leukemia and non-Hodgkins lymphoma. It is also a substrate of Breast cancer resistance protein (Bcrp). Downregulation of the expression of Bcrp has been demonstrated in intrahepatic cholestasis. The aim of this study was to explore whether CBS could influence the hepatic-biliary transportation of mitoxantrone in EE induced cholestasis. A single dose of baicalin (20mg/kg, i.v.) was given to rat pretreated with CBS (50or150mg/kg, per day, intragastrically) or normal saline (NS, per day, intragastrically) for seven consecutive days. At day5, rats were given ANIT (100mg/kg) to induce intrahepatic cholestasis except the normal control group. Bile concentration of baicalin was measured with HPLC method. A single dose of mitoxantrone (2mg/kg, i.v.) was given to rat pretreated with CBS (50or150mg/kg, per day, intragastrically) or normal saline (NS, per day, intragastrically) for five consecutive days. The rats were treated with EE (5mg/kg, s.c.) once per day to induce intrahepatic cholestasis except the normal control group. Bile concentration of mitoxantrone was measured with HPLC method. The result indicated that the bile excretion rate of baicalin after injection was significantly decreased in rats pretreated with ANIT compared with control rats. CBS treatment partly reversed this inhibition effect of ANIT at doses of50or150mg/kg. The bile excretion rate and the the accumulative amount of baicalin in bilie were significantly increased with CBS treatment compared with ANIT only group. The bile excretion rate of mitoxantrone after injection was significantly decreased in rats pretreated with EE compared with control rats. CBS treatment partly reversed this inhibition effect of EE at doses of50or150mg/kg. The bile excretion rate and the the accumulative amount of mitoxantrone in bilie were significantly increased with CBS treatment compared with EE only group. Hence, CBS treatment increased-the bile excretion rate and the the accumulative amount of baicalin in bile compared with ANIT only group, probably due to the enhanced efflux of baicalin from liver by Mrp2. And CBS treatment partly restored the bile excretion rate and the cumulative amount of mitoxantrone in bile compared with EE group, possibly due to the restoration of transport activity of hepatic Bcrp. |
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