Metabolic profile of bile acids was used to evaluate hepatotoxicity of mice caused by ethanol extraction of Dioscorea bulbifera L. (ethanol extraction, ET) and diosbulbin B (DB), separately. Ultra-performance liquid chromatography coupled with quadrupole mass spectrometry (UPLC-MS) was applied to determine the contents of all kinds of endogenous bile acids including free bile acids, taurine conjugates and glycine conjugates. Obvious liver injuries could be observed in mice after administrated with ET and DB. Based on the analysis using principle components analysis (PCA), toxic groups could be distinguished from their control groups, which suggested that the variance of the contents of bile acids could evaluate hepatotoxicity caused by ET and DB. Meanwhile, ET and DB toxic groups were classified in the same trends comparing to control groups in the loading plot, and difference between the two toxic groups could also be observed. DB proved to be one of the toxic components in Dioscorea bulbifera L. Bile acids of tauroursodeoxycholic acid (TUDCA), taurochenodeoxycholic acid (TCDCA), taurocholic acid (TCA), taurodeoxycholic acid (TDCA), cholic acid (CA) and others proved to be important corresponds to ET and DB induced liver injury according to analysis of partial least square-discriminant analysis (PLS-DA) and the statistical analysis showed that there were significant differences between the control groups and toxic groups (P < 0.01). Furthermore, good correlation could be revealed between the foregoing bile acids and ALT, AST. It indicated that taurine conjugated bile acids as TUDCA, TCDCA, TCA and TDCA along with CA could be considered as sensitive biomarkers of ET and DB induced liver injury. This work can provide the base for the further research on the evaluation and mechanism of hepatotoxicity caused by Dioscorea bulbifera L.
Animals ; Bile Acids and Salts ; metabolism ; Chemical and Drug Induced Liver Injury ; metabolism ; Cholic Acid ; metabolism ; Chromatography, High Pressure Liquid ; methods ; Dioscorea ; toxicity ; Drugs, Chinese Herbal ; isolation & purification ; toxicity ; Heterocyclic Compounds, 4 or More Rings ; isolation & purification ; toxicity ; Least-Squares Analysis ; Male ; Mice ; Mice, Inbred ICR ; Plants, Medicinal ; toxicity ; Principal Component Analysis ; Rhizome ; toxicity ; Tandem Mass Spectrometry ; methods ; Taurochenodeoxycholic Acid ; metabolism ; Taurocholic Acid ; metabolism ; Taurodeoxycholic Acid ; metabolism

Tanreqing (TRQ), a traditional Chinese medicine (TCM) formula, can alleviate liver injury and improve liver function. Its pharmacological mechanisms of actions are still unclear due to its complex components and multi-target natures. Metabolomic study is an effective approach to investigating drug pharmacological actions, new diagnostic markers, and potential mechanisms of actions. In the present study, a new strategy was used to evaluate the protective effect of TRQ capsule against carbon tetrachloride (CCl)-induced hepatotoxicity in rats, by analyzing metabolic profiling of endogenous bile acids (BAs) along with biochemical and histological analyses. BAs concentrations were determined by ultra-performance liquid chromatography coupled with quadrupole mass spectrometry (UPLC-MS). Principal component analysis and partial least squares discriminant analysis were then employed to analyze the UPLC-MS results and compare the hepatoprotective effect of TRQ capsule in different groups at the doses of 0.36, 1.44, and 2.88 g·kg body weight, respectively. Moreover, our results suggested that taurocholic acid (TCA) and taurohyodesoxycholic acid (THDCA) were the most important biochemical markers, which were indicative of CCl-induced acute hepatic damage and hepatoprotective effect of TRQ capsule. Therefore, this new strategy would be an excellent alternative method for evaluating hepatoprotective effect and proposing potential mechanisms of action for other drugs as well.
Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Bile Acids and Salts ; blood ; metabolism ; Biomarkers ; blood ; Carbon Tetrachloride ; pharmacology ; Chemical and Drug Induced Liver Injury ; drug therapy ; metabolism ; pathology ; Chromatography, Liquid ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; therapeutic use ; Female ; Liver ; drug effects ; pathology ; Male ; Mass Spectrometry ; Metabolome ; drug effects ; Metabolomics ; Rats ; Rats, Wistar ; Taurocholic Acid ; blood ; Taurodeoxycholic Acid ; analogs & derivatives ; blood

PURPOSE: The possible mechanisms of increased thiol me thyltransferase (TMT) activity in cholestatic rat livers and serum were studied. METHODS: Rats were divided into seven groups: rats receiv ing a sham operation, rats with a bile duct obstruction (BDO) alone (BDO group), rats with BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), rats with BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), rats receiving a choledoco-caval shunt (CCS) operation (CCS groups), rats receiving a CCS operation plus TCA Injection (CCS plus TCA group), and rats receiving a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TMT activities in the serum and in the hepatic subcellular fractions isolated from these experimental rats were determined. The values of Km and Vmax in this he patic enzyme were measured. RESULTS: The activities of liver mitochondrial and microsomal TMTs as well as the Vmax values of TMT were found to be increased significantly in both the CCS plus TCA and the BDO plus TCA groups, compared with the CCS and BDO groups. On the other hand, the Km values of hepatic subcellular TMT were the same in all experimental groups. The serum TMT activity increased significantly in both the CCS plus TCA and the BDO plus TCA groups, compared with the control, CCS and BDO groups. However, these serum and hepatic enzyme activities were the same in the CCS plus TUDCA and the BDO plus TUDCA groups. CONCLUSION: The above results suggest that TCA stimulates the biosynthesis of TMT in the liver. Also, the elevated TMT activity in the serum is thought to be caused by an increase in membrane permeability of hepatocytes from liver cell necrosis caused by TCA.
Administration, Intravenous* ; Animals ; Cholestasis ; Hand ; Hepatocytes ; Liver ; Membranes ; Necrosis ; Permeability ; Rats* ; Subcellular Fractions ; Taurocholic Acid*

BACKGROUND/AIMS: In order to elucidate the possible mechanism of increase of y-glutamyl transpeptidase (y-GTP) activity in cholestatic liver and serum was studied. METHOD: Rats were divided into eight groups: Normal, sham operated control, bile duct obstruction (BDO) alone (BDO group), BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), choledoco-caval shunt (CCS) operation (CCS groups), CCS plus TCA injection (CCS plus TCA group), and CCS plus TUDCA injection (CCS plus TUDCA group). Y-GTP activity was determined in the serum and liver cytosolic, mitochondrial and microsomal preparations isolated from above experimental rats. The values of Km and Vmax in this hepatic enzyme was measured. RESULT: the activities of liver cytosolic and microsomal y-GTP showed a significant increase in the CCS group. The activities of liver cytosolic, mitochondrial and microsomal y-GTP showed a significant increase in the BDO group. And the activity of serum y-GTP showed a marked increase in teth CCS and BDO poups. However, y-GTP activities in the serum and in liver microsomal prepatation rose more rapidly in the BDO group tban CCS. Y-GTP activity in liver cytosolic and microsomal preparatians, and its Vmax value incmmxl significantly in both CCS plus TCA group, and BDO plus TCA group than each control group, such as CCS and BDO group. On the other hand, the values of Km of the hepatic subcellular y-GTP did not change in the all experimental groups. Sennn y-GTP activity increased significantly in both CCS plus 7CA group, and BDO plus TCA group than each control group. However, these serum and hepatic enzyme activities did not change in both CCS plus TUDCA group and BDO plus TUDCA group. CONCLUSIONS: The above results suggest that 7CA stimulates biosynthesis of the y-GTP in the liver. And the elevations of the serum enzymes activity thought to be caused by increase of hepatocyte membrane permeability by a physical property (detergency) of TCA, which cause the enzyme to leak into the blood in large quantities.
Animals ; Bile* ; Cholestasis ; Cytosol ; gamma-Glutamyltransferase* ; Hand ; Hepatocytes ; Liver* ; Membranes ; Permeability ; Rats* ; Taurocholic Acid

PURPOSE: The possible mechanisms of increased arylamine N-methyl- transferase (AMT) activity in cholestatic rat livers and serum were studied. METHODS: Rats were divided into eight groups: rats receiving a sham operation, rats with a bile duct obstruction (BDO) alone (BDO group), rats with a BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), rats with a BDO plus tauroursode oxycholic acid (TUDCA) injection (BDO plus TUDCA group), rats receiving a choledocho-caval shunt (CCS) operation (CCS groups), rats receiving a CCS operation plus TCA injection (CCS plus TCA group), and rats receiving a CCS operation plus TUDCA injection (CCS plus TUDCA group). The AMT activities in the serum and in the hepatic subcellular fractions isolated from the above experimental rats were determined. The values of Km and Vmax in this hepatic enzyme were measured. RESULTS: The activities of liver mitochondrial and microsomal AMTs as well as the Vmax values of AMT, were found to be increased significantly in both the CCS plus TCA group and the BDO plus TCA group compared with the CCS and BDO groups. On the other hand, the values of Km of hepatic subcellular AMT was the same in all experimental groups. The serum AMT activity increased significantly in both the CCS plus TCA group and the BDO plus TCA group compared with control the CCS and BDO group. However, these serum and hepatic enzyme activities were the same in both the CCS plus TUDCA group and the BDO plus TUDCA group. CONCLUSION: The above results suggest that TCA stimulates the biosynthesis of AMT in the liver. Also, the elevated AMT activity in the serum is thought to be caused by an increase in the membrane permeability of hepatocytes from liver cell necrosis caused by TCA.
Animals ; Cholestasis ; Cholestasis, Extrahepatic ; Hand ; Hepatocytes ; Liver ; Membranes ; Necrosis ; Permeability ; Rats* ; Subcellular Fractions ; Taurocholic Acid* ; Transferases

BACKGROUND/AIMS: Our previous studies of ionization and solubility of unconjugated bilirubin (UCB) yielded inappropriately large differences between the two carboxylic pK'a values of UCB. These data, however, were not ideal due to crystal effects, matastability, impurities of the bilirubin, and imprecision of analyses at low UCB. METHODS: The sodium salt of taurocholate (TC) was purified and dissolved in water to 100 mM. Chloroform (CHCl3) was purified by vacuum distillation. Buffers used were: citrate from pH 4 to 6, phosphate from pH 6 to 8, and borate above pH 8. All had an ionic strength of 0.10. The problems were minimized by rapid solvent partition of UCB from CHCl3 into buffered aqueous NaCl, and a new, accurate assay of low UCB in the aqueous phase which was achieved by concentrating the UCB through back extraction into small volumes of CHCl3. RESULTS: In contrast with the crystal dissolution studies, the two pK'a value were similar. H2B0, not HB-, was the dominant UCB species in the pH range of bile (6.0 to 8.0). The aqueous solubilities of UCB were 90 to 98% less. Less than 0.01% of the bile salt partitioned into the CHCl3 phase and self-association of B= was negligible. UCB solubilities in 50 mM TC were 2 to 10% of those obtained by crystal dissolution, and, up to pH 7.9, were below the maximum UCB concentration in normal human bile. CONCLUSIONS: We suggest that the markedly increased binding of UCB with each ionization step is due to the disruption of the internal hydrogen bonds of the ionized carboxyl groups on interaction with the bile salt. We propose to extend the study of partition to determine the activity and the degradation products of calcium salts of unbound bilirubin fractions.
Bilirubin/*chemistry ; Chloroform ; English Abstract ; Hydrogen-Ion Concentration ; In Vitro ; Solubility ; Solvents ; Taurocholic Acid/*chemistry

BACKGROUND: Although several pathophysiological sequences, such as protease activation, free radical generation, and inflammatory mediator release, have been described in acute pancreatitis, the precise mechanism by which acute pancreatitis is initiated is unkown. Cellular calcium, a key function and also a crucial pathological intracellular messenger in cell injury, appears to be involved in the initiation and development of acute pancreatitis. The aim of this study is to evaluate the role of cellular calcium and therapeutic effect of administering the Ca++ channel blocker nicadipine as an antioxidant. METHOD:Nicardipine, known to be a calcium channel blocker and a most potent antioxidant, was wed as a pretreatment 1 hour before induction of pancreatitis by intraductal infusion of 3% sodium taurocholate or as a post-treatment 1 hour after induction of aucte pancreatitis by retrograde infusion of sodium taurocholate. The net weight of the pancrease, the amounts of s-amylse, GSH and MDA in the pancreatic tissue, and the histologic damage were examined 12 hours after the induction of pancreatitis. RESULTS: Nicardipine administration ameliorated pancreatic edema and reduced the amount of s-amylase compare to untreated necrotizing pancreatitis group. Also, pre- or post-treatment with nicardipine had beneficial protective effect with respect to free radical-induced injury; in particular, pre-treatment with nicardipine was much better. With respect to the histologic findings, pancreatic necrosis, hemorrhage, and neutrophil infiltration were prominent in the necrotizing group, however, in the group treated with nicardipine, the necrosis and hemorrhage were ameliorated remarkably. CONCLUSION:The free oxygen radicals and the intracellular calcium influx were major elements in the pathogenesis of acute pancreatitis, and nicardipine ameliorated pancreatic necrosis and hemorrage and exerted an antioxidant effect. The administration of nicardipine should be considered in the early stage of pancreatitis or in case of risk of pancreatitis.
Antioxidants ; Calcium Channels* ; Calcium* ; Edema ; Hemorrhage ; Necrosis ; Neutrophil Infiltration ; Nicardipine* ; Pancreas ; Pancreatitis* ; Pancrelipase ; Reactive Oxygen Species ; Taurocholic Acid

PURPOSE: To Study the possible mechanisms of change of thiosulfate sulfurtransferase (TST) activity in cholestatic rat liver and serum. METHODS: Rats were divided into seven groups: those receiving a sham operation (Sham group), with a bile duct obstruction (BDO) alone (BDO group), with a BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), with a BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), a choledocho-caval shunt (CCS) operation (CCS groups), a CCS operation plus TCA injection (CCS plus TCA group) and a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TST activities in the serum and in the hepatic subcellular fractions isolated from above experimental rats were determined. The Km and Vmax values of this hepatic enzyme were measured. RESULTS: The liver cytosolic, mitochondrial and microsomal TSTs activities, as well as the TST Vmax values were found to be significantly decreased in the BDO plus TCA and BDO groups compared to the control group. The activity and Vmax value of the liver cytosolic TST were also found to be significantly decreased in the CCS plus TCA group. Conversely, there was no variation in the Km values of the hepatic enzymes in any of the above experimental groups. The serum TST activities in the CCS plus TCA and BDO plus TCA groups, were significantly increased compared with the control, CCS and BDO groups. However, the serum and hepatic enzyme activities were unchanged in both the CCS plus TUDCA and BDO plus TUDCA groups. CONCLUSION: The above results indicate that TCA represses the biosynthesis of TST in the liver. Also, the elevated TST activity in the serum is most likely due to an increase in the permeability of hepatocytes membrane upon TCA mediated liver cell necrosis.
Administration, Intravenous* ; Animals ; Cholestasis ; Cytosol ; Hepatocytes ; Liver* ; Membranes ; Necrosis ; Permeability ; Rats* ; Subcellular Fractions ; Taurocholic Acid* ; Thiosulfate Sulfurtransferase*

PURPOSE: To Study the possible mechanisms of change of thiosulfate sulfurtransferase (TST) activity in cholestatic rat liver and serum. METHODS: Rats were divided into seven groups: those receiving a sham operation (Sham group), with a bile duct obstruction (BDO) alone (BDO group), with a BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), with a BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), a choledocho-caval shunt (CCS) operation (CCS groups), a CCS operation plus TCA injection (CCS plus TCA group) and a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TST activities in the serum and in the hepatic subcellular fractions isolated from above experimental rats were determined. The Km and Vmax values of this hepatic enzyme were measured. RESULTS: The liver cytosolic, mitochondrial and microsomal TSTs activities, as well as the TST Vmax values were found to be significantly decreased in the BDO plus TCA and BDO groups compared to the control group. The activity and Vmax value of the liver cytosolic TST were also found to be significantly decreased in the CCS plus TCA group. Conversely, there was no variation in the Km values of the hepatic enzymes in any of the above experimental groups. The serum TST activities in the CCS plus TCA and BDO plus TCA groups, were significantly increased compared with the control, CCS and BDO groups. However, the serum and hepatic enzyme activities were unchanged in both the CCS plus TUDCA and BDO plus TUDCA groups. CONCLUSION: The above results indicate that TCA represses the biosynthesis of TST in the liver. Also, the elevated TST activity in the serum is most likely due to an increase in the permeability of hepatocytes membrane upon TCA mediated liver cell necrosis.
Administration, Intravenous* ; Animals ; Cholestasis ; Cytosol ; Hepatocytes ; Liver* ; Membranes ; Necrosis ; Permeability ; Rats* ; Subcellular Fractions ; Taurocholic Acid* ; Thiosulfate Sulfurtransferase*

We have examined whether bile acids can affect the electrical and mechanical activities of circular smooth muscle of canine colon and ileum, using isometric tension measurement or patch clamp technique. It was found that a dilution of canine bile (0.03 ~ 2% by volume) enhanced or inhibited the amplitude of spontaneous contractions. An individual component of bile, deoxycholic acid (DCA) enhanced the frequency and amplitude of the spontaneous contractile activity at 10(-6) M, while DCA at 10(-4) M inhibited the contraction. Similarly, the response to cholic acid was excitatory at 10(-5) M and inhibitory at 3 X 10(-4) M. Taurocholic acid at 10(-4) M enhanced the amplitude of muscle contraction. Electrically, canine bile at 1% reversibly depolarized the colonic myocytes under current clamp mode. Bile acids also elicited non-selective cation currents under voltage clamp studies, where K+ currents were blocked and the Cl- gradient was adjusted so that ECl- was equal to -70 mV, a holding potential. The non-selective cation current might explain the depolarization caused by bile acids in intact muscles. Furthermore, the bile acid regulation of electrical and mechanical activities of intestinal smooth muscle may explain some of the pathophysiological conditions accompanying defects in bile reabsorption.
Bile Acids and Salts ; Bile* ; Cholic Acid ; Colon ; Deoxycholic Acid ; Gastrointestinal Motility ; Ileum ; Muscle Cells ; Muscle Contraction ; Muscle, Smooth* ; Muscles ; Taurocholic Acid