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Plasma ALT (plasma + alt)
Selected Abstracts,-Glucuronidase inhibitor tectorigenin isolated from the flower of Pueraria thunbergiana protects carbon tetrachloride-induced liver injuryLIVER INTERNATIONAL, Issue 4 2003Hae-Woong Lee Abstract Background/Aim: To understand the relationship between the fluctuation in serum ,-glucuronidase and hepatotoxicity, an inhibitor of ,-glucuronidase was isolated from the flowers of Pueraria thunbergiana and its hepatoprotective activity was measured. Method: Tectorigenin was isolated from the flowers of pueria thunbergiana as an inhibitor of ,-glucuronidase, and serum ALT, AST and biological parameters as markers for its hepatoprotective activity were measured on CCl4 -induced liver injury in mice. The relationship between serum ,-glucuronidase and hepatoprotective activities in mice was measured. Results: When tectorigenin at a dose of 100 mg/kg was intraperitoneally administered on CCl4 -induced liver injury in mice, it significantly inhibited the increase of plasma ALT, AST and LDH activities. The inhibitory effect of tectorigenin is much more potent than that of dimethyl diphenyl bicarboxylate (DDB), which has been used as a commercial hepatoprotective agent. When tectoridin transformed to tectorigenin by intestinal bacteria was orally administered to mice, it showed hepatoprotective activity. However, when tectoridin was intraperitoneally administrated to mice, it did not exhibit hepatoprotective activity. Moreover, orally administered tectoridin not only inhibited ,-glucuronidase but also increased GSH content and GST activity on CCl4 -induced hepatotoxicity of mice. Conclusion: We insist that an inhibitor of ,-glucuronidase tectorigenin may be hepatoprotective and tectoridin should be a prodrug transformed to tectorigenin. [source] Hepatoprotective activity of aqueous,methanol extract of Artemisia vulgarisPHYTOTHERAPY RESEARCH, Issue 2 2005Anwarul Hassan Gilani Abstract The effect of a crude extract of the aerial parts of Artemisia vulgaris (Av.Cr) was investigated against D -galactosamine (D -GalN) and lipopolysaccharide (LPS) induced hepatitis in mice. Co-administration of D -GalN (700 mg[sol ]kg) and LPS (1 µg[sol ]kg) significantly (p < 0.05) raised the plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in mice in the toxin group compared with the values in the control group. Pre-treatment of mice with different doses of Av.Cr (150,600 mg[sol ]kg) significantly (p < 0.05) reduced the toxin-induced rise in plasma ALT and AST. The hepatoprotective effect was further verified by histopathology of the liver, which showed improved architecture, absence of parenchyma congestion, decreased cellular swelling and apoptotic cells, compared with the findings in the toxin group of animals. These findings scientifically validated the traditional use of Artemisia vulgaris for various liver disorders. Copyright © 2005 John Wiley & Sons, Ltd. [source] Hepatoprotective and antioxidant activities of Tetracera loureiriPHYTOTHERAPY RESEARCH, Issue 7 2003Veerapol Kukongviriyapan Abstract Tetracera loureiri is one of the most valued herbs in Thai traditional medicine. In this study, we describe its in vitro and in vivo antioxidant and hepatoprotective activities. The ethanol extract of T. loureiri possessed potent antioxidant and strong free radical scavenging properties assayed using ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), respectively. The cytoprotective effects of T. loureiri were demonstrated in ethanolic extracts of freshly isolated rat hepatocytes against the chemical toxicants paracetamol and tertiary-butylhydroperoxide. The cells pretreated with the extract maintained the GSH/GSSG ratio and suppressed lipid peroxidation in a dose dependent manner. Pretreating rats with the ethanol extract orally, one hour prior to intraperitoneal injection of toxic doses of paracetamol, signi,cantly prevented elevations of plasma ALT and AST. These results suggest that T. loureiri may be of potential therapeutic value in some liver disorders. Copyright © 2003 John Wiley & Sons, Ltd. [source] Hydrodynamics-based procedure involves transient hyperpermeability in the hepatic cellular membrane: implication of a nonspecific process in efficient intracellular gene deliveryTHE JOURNAL OF GENE MEDICINE, Issue 5 2004Naoki Kobayashi Abstract Background The mechanisms underlying the efficient gene transfer by a large-volume and high-speed intravenous injection of naked plasmid DNA (pDNA), a so-called hydrodynamics-based procedure, remain unclear and require further investigation. In this report, we have investigated possible mechanisms for the intracellular transport of naked pDNA by this procedure. Methods Propidium iodide (PI), a fluorescent indicator for cell membrane integrity, and luciferase- or green fluorescent protein (GFP)-expressing pDNA were injected into mice by the hydrodynamics-based procedure. Results PI was efficiently taken up by hepatocytes which appeared to be viable following the hydrodynamics-based procedure. Pre-expressed GFP in the cytosol was rapidly eliminated from the hepatocytes by a large-volume injection of saline. The profiles of plasma ALT and AST showed a steady decline with the highest values observed immediately after the hydrodynamics-based procedure. These results suggest that the hydrodynamics-based procedure produces a transient increase in the permeability of the cell membrane. The cellular uptake process appeared nonspecific, since simultaneous injection of an excess of empty vector did not affect the transgene expression. Sequential injections of a large volume of pDNA-free saline followed by naked pDNA in a normal volume revealed that the increase in membrane permeability was transient, with a return to normal conditions within 30 min. Transgene expression was observed in hepatocyte cultures isolated 10 min after pDNA delivery and in the liver as early as 10 min after luciferase-expressing RNA delivery, indicating that pDNA delivered immediately by the hydrodynamics-based procedure has the potential to produce successful transgene expression. Conclusions These findings suggest that the mechanism for the hydrodynamics-based gene transfer would involve in part the direct cytosolic delivery of pDNA through the cell membrane due to transiently increased permeability. Copyright © 2004 John Wiley & Sons, Ltd. [source] Protective effects of N-acetyl- L -cysteine against acute carbon tetrachloride hepatotoxicity in ratsCELL BIOCHEMISTRY AND FUNCTION, Issue 1 2008Yu. Z. Maksimchik Abstract In recent years, N-acetyl- L -cysteine (NAC) has been widely investigated as a potentially useful protective and antioxidative agent to be applied in many pathological states. The aim of the present work was further evaluation of the mechanisms of the NAC protective effect under carbon tetrachloride-induced acute liver injuries in rats. The rat treatment with CCl4 (4,g/kg, intragastrically) caused pronounced hepatolysis observed as an increase in blood plasma bilirubin levels and hepatic enzyme activities, which agreed with numerous previous observations. The rat intoxication was accompanied by an enhancement of membrane lipid peroxidation (1.4-fold) and protein oxidative damage (protein carbonyl group and mixed protein-glutathione disulphide formations) in the rat liver. The levels of nitric oxide in blood plasma and liver tissue significantly increased (5.3- and 1.5-fold, respectively) as blood plasma triacylglycerols decreased (1.6-fold). The NAC administration to control and intoxicated animals (three times at doses of 150,mg/kg) elevated low-molecular-weight thiols in the liver. The NAC administration under CCl4 -induced intoxication prevented oxidative damage of liver cells, decreased membrane lipid peroxidation, protein carbonyls and mixed protein-glutathione disulphides formation, and partially normalized plasma triacylglycerols. At the same time the NAC treatment of intoxicated animals did not produce a marked decrease of the elevated levels of blood plasma ALT and AST activities and bilirubin. The in vitro exposure of human red blood cells to NAC increased the cellular low-molecular-weight thiol levels and retarded tert -butylhydroperoxide-induced cellular thiol depletion and membrane lipid peroxidation as well as effectively inhibited hypochlorous acid-induced erythrocyte lysis. Thus, NAC can replenish non-protein cellular thiols and protect membrane lipids and proteins due to its direct radical-scavenging properties, but it did not attenuate hepatotoxicity in the acute rat CCl4 -intoxication model. Copyright © 2007 John Wiley & Sons, Ltd. 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