Search Results
Results 301 - 350 of 3759
< 2 3 4 5 6 7 8 9 10 11 12 >
Sanyal Sabyasachi - - 2007
Coordinated regulation of bile acid biosynthesis, the predominant pathway for hepatic cholesterol catabolism, is mediated by few key nuclear receptors including the orphan receptors liver receptor homolog 1 (LRH-1), hepatocyte nuclear factor 4alpha (HNF4alpha), small heterodimer partner (SHP), and the bile acid receptor FXR (farnesoid X receptor). Activation of FXR ...
Duane William C - - 2008
Using a luciferase reporter assay we found that human serum transactivated the ileal apical sodium-dependent bile acid transporter (ASBT) promoter three to fourfold. Confirming this effect, addition of human serum to both Caco-2 cells and fresh human ileal biopsies caused an approximate 2.0-fold increase in endogenous ASBT mRNA production. Alteration ...
Wang Li - - 2008
The pharmacokinetics and metabolism of lithospermic acid (LA), a component isolated from Salvia miltiorrhiza, and its two O-methylated metabolites (3'-monomethyl- and 3',3''-dimethyl-lithospermic acid), were analyzed by a rapid and specific isocratic liquid chromatography-tandem mass spectrometry (LC/MS/MS) method. Rat serum samples collected after intravenous and oral administration were analyzed for obtaining ...
Jung Diana - - 2007
Bile acid malabsorption, which in patients leads to excessive fecal bile acid excretion and diarrhea, is characterized by a vicious cycle in which the feedback regulation of bile acid synthesis is interrupted, resulting in additional bile acid production. Feedback regulation of bile acid synthesis is under the control of an ...
Kakiyama Genta - - 2007
The major bile acids present in the gallbladder bile of the common Australian wombat (Vombatus ursinus) were isolated by preparative HPLC and identified by NMR as the taurine N-acylamidates of chenodeoxycholic acid (CDCA) and 15alpha-hydroxylithocholic acid (3alpha,15alpha-dihydroxy-5beta-cholan-24-oic acid). Taurine-conjugated CDCA constituted 78% of biliary bile acids, and (taurine-conjugated) 15alpha-hydroxylithocholic acid ...
Sharma Vikas - - 2007
BACKGROUND/AIMS: Long standing calculus disease has been observed to be a risk factor for gallbladder carcinoma. However it is possible that calculi may be incriminated by some means other than just chronic irritation. Calculi may induce an element of stasis, promoting chronic infection leading to increased turnover of primary bile ...
Mitro Nico - - 2007
The transcription of the gene (CYP7A1) encoding cholesterol 7alpha-hydroxylase, a key enzyme in cholesterol homeostasis, is repressed by bile acids via multiple mechanisms involving members of the nuclear receptor superfamily. Here, we describe a regulatory mechanism that can be exploited for modulating bile acid synthesis. By dissecting the mechanisms of ...
Zollner Gernot - - 2007
Bile acid synthesis, transport and metabolism are markedly altered in experimental cholestasis. Whether such coordinated regulation exists in human cholestatic diseases is unclear. We therefore investigated expression of genes for bile acid synthesis, detoxification and alternative basolateral export and regulatory nuclear factors in primary biliary cirrhosis (PBC). Hepatic CYP7A1, CYP27A1, ...
Tan Kah Poh - - 2007
Oxidative stress, causing necrotic and apoptotic cell death, is associated with bile acid toxicity. Using liver (HepG2, Hepa1c1c7, and primary human hepatocytes) and intestinal (C2bbe1, a Caco-2 subclone) cells, we demonstrated that toxic bile acids, such as lithocholic acid (LCA) and chenodeoxycholic acid, induced the nuclear factor (erythroid-2 like) factor ...
Leslie Elaine M - - 2007
The role of uptake and efflux transport proteins in the tissue distribution of the tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and its metabolites is largely unknown. Carbonyl reduction of NNK results in formation of the carcinogenic 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which in rats is glucuronidated to the non-toxic NNAL-O-glucuronide. Previous in vitro studies showed ...
Kim Insook I Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, - - 2007
Bile acid concentrations are controlled by a feedback regulatory pathway whereby activation of the farnesoid X receptor (FXR) represses transcription of both the CYP7A1 gene, encoding the rate-limiting enzyme in the classic bile acid synthesis pathway, and the CYP8B1 gene, required for synthesis of cholic acid. The tissue-specific roles of ...
Pellicciari Roberto - - 2007
23-Alkyl-substituted and 6,23-alkyl-disubstituted derivatives of chenodeoxycholic acid are identified as potent and selective agonists of TGR5, a G-protein coupled receptor for bile acids (BAs). In particular, we show that methylation at the C-23(S) position of natural BAs confers a marked selectivity for TGR5 over FXR, while the 6alpha-alkyl substitution increases ...
Kalia N - - 2008
OBJECTIVE: Observations showing that bile acid malabsorption is frequent in irritable bowel syndrome (IBS) suggest that alterations in bile acid-induced secretion and absorption could contribute to IBS-associated diarrhoea. The secretory response to bile acids, fluid transport and bile absorption was examined in intestinal tissues from a Trichinella spiralis mouse model ...
Fischler B - - 2007
BACKGROUND: An increasing number of treatable inborn errors of bile acid synthesis have been described, primarily in infants with severe cholestatic liver disease. RESULTS: The present patient, whose two older siblings had died from progressive cholestatic liver disease, developed neonatal cholestasis and rickets but recovered during the childhood years and ...
Heubi James E - - 2007
Bile acids are synthesized by the liver from cholesterol through a complex series of reactions involving at least 14 enzymatic steps. A failure to perform any of these reactions will block bile acid production with failure to produce "normal bile acids" and, instead, result in the accumulation of unusual bile ...
Ruiz Lorena - - 2007
Bifidobacterium animalis ssp. lactis is a probiotic frequently used as adjunct culture in fermented dairy products. In order to ensure its proper function at the intestinal level, this bacterium has to be tolerant to physiological concentrations of bile. This study examined the influence of bile on the fatty acid composition ...
Yang Jong In - - 2007
TGR5 is a novel G protein-coupled cell-surface bile acid receptor. In cholestasis, bile acids induce hepatocyte apoptosis by primarily activating death receptor-mediated signaling. We examined if bile acid-induced TGR5 activation is participating in bile acid-induced hepatocyte apoptosis. TGR5 expression and its responsiveness to bile acid were confirmed in human hepatocytes. ...
Nomoto Masahiro - - 2007
ME3738 (22beta-methoxyolean-12-ene-3beta, 24(4beta)-diol), a derivative of soyasapogenol, attenuates liver disease in several models of chronic liver inflammation. In the present study, we have investigated a protective effect of ME3738 in a typical bile acid-induced cholestatic liver model, lithocholate (LCA) feeding mouse. Co-administration of ME3738 resulted in decreases in plasma alanine ...
Kurosu Hiroshi H Departments of Pathology and Molecular Biology, University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Boulevard, Dallas, TX 75390, - - 2007
The fibroblast growth factor (FGF) 19 subfamily of ligands, FGF19, FGF21, and FGF23, function as hormones that regulate bile acid, fatty acid, glucose, and phosphate metabolism in target organs through activating FGF receptors (FGFR1-4). We demonstrated that Klotho and betaKlotho, homologous single-pass transmembrane proteins that bind to FGFRs, are required ...
Loumbourdis N S - - 2007
The various histopathologic alterations detected in the liver of the frog Rana ridibunda from a small river of Northern Greece were investigated. In the livers of the frogs collected from this river, there was an increase in the area occupied by melanomacrophages as well as an increase in their color ...
Chang Kyeong-Ok - - 2007
Hepatitis C virus (HCV) is a cause of chronic liver disease, with more than 170 million persistently infected individuals worldwide. Although the combination therapy of alpha interferon (IFN-alpha) and ribavirin is effective for chronic HCV infection, around half of all patients infected with HCV genotype 1 fail to show sustained ...
Hu Yingchuan - - 2007
INTRODUCTION: Clinical evidence strongly suggests that bile acids are important in the development of Barrett's esophagus, although the mechanism remains unknown. Caudal-related homeobox 2 (CDX2) is a transcription factor recently implicated in early differentiation and maintenance of normal intestinal epithelium and is suggested to play a key role in the ...
Ueno Yoshiyuki - - 2007
Cholangiopathies, such as primary biliary cirrhosis and primary sclerosis cholangitis, are characterized at the end stage by ductopenia due to increased cholangiocyte apoptosis and decreased cholangiocyte proliferation. Although cholangiocyte proliferation is associated with an increased number of intra-hepatic bile ducts and secretin-stimulated ductal secretion, ductopenia is coupled with decreased ductal ...
Shea Heidi C - - 2007
Primary bile acids are synthesized from cholesterol in the liver and thereafter are secreted into the bile and small intestine. Gut flora modify primary bile acids to produce secondary bile acids leading to a chemically diverse bile acid pool that is circulated between the small intestine and liver. A majority ...
Song Shumei - - 2007
Bile reflux contributes to oesophageal injury and neoplasia. COX-2 is involved in both inflammation and carcinogenesis; however, the precise mechanisms by which bile acids promote COX-2 expression in the oesophagus are largely unknown. We analysed the molecular mechanisms that govern bile acid-mediated expression of COX-2 in Barrett's oesophagus and oesophageal ...
Tyagi Punam - - 2007
Human and animal wastes are major sources of environmental pollution. Reliable methods of identifying waste sources are necessary to specify the types and locations of measures that best prevent and mitigate pollution. This investigation demonstrates the use of chemical markers (fecal sterols and bile acids) to identify selected sources of ...
Cai Shi-Ying - - 2007
The nuclear receptor FXRalpha (NR1H4) plays a pivotal role in maintaining bile salt and lipid homeostasis by functioning as a bile salt sensor in mammals. In contrast, FXRbeta (NR1H5) from mouse is activated by lanosterol and does not share common ligands with FXRalpha. To further elucidate FXR ligand/receptor and structure/function ...
Hu Yingchuan - - 2007
HYPOTHESIS: Bile acid exposure can induce caudal-related homeobox 2 (CDX2) messenger RNA (mRNA) expression, a transcription factor that plays a crucial role in the development of Barrett esophagus. We investigated mucin 2 (MUC2) and CDX2 mRNA expression before and after treatment with deoxycholic acid in 4 human esophageal cell lines. ...
De Corso Eugenio - - 2007
The aim of our study was to detect bile acids and total bilirubin in saliva of gastrectomized patients, to confirm objectively presence of biliary laryngopharyngeal reflux and its relationship with laryngeal mucosa damage. Recently, it has been hypothesized that biliary-reflux may reach the upper aerodigestive tract and enhance development of ...
Lövgren-Sandblom Anita - - 2007
A new isotope dilution LC-MS/MS method for assay of 7alpha-hydroxy-4-cholesten-3-one without need for derivatization is described. This method was used in catheterization experiments on healthy fasting volunteers. The levels of this generally used marker for bile acid synthesis were slightly but significantly higher in the hepatic vein than in the ...
Scheimann A O - - 2007
Fatal peripheral cholangiocarcinoma developed in 2 girls with progressive familial intrahepatic cholestasis, ABCB11 mutations, and absent bile salt export pump (BSEP) expression. BSEP deficiency may cause cholangiocarcinoma through bile-composition shifts or bile-acid damage within cells capable of hepatocytic/cholangiocytic differentiation. This observation suggests the need for hepatobiliary-malignancy surveillance and early consideration ...
Tadano Tomoaki - - 2007
PURPOSE: We used gas chromatography mass spectrometry (GC-MS) and reviewed dynamics of bile acids every colorectal cancer occupation part as contrast with a healthy adults after enforcement by all at once analysis of bile acids in feces of a healthy adults and the colorectal cancer patients so that we clarified ...
Yamagata Kazuyuki - - 2007
Bile acid homeostasis is tightly controlled by the feedback mechanism in which an atypical orphan nuclear receptor (NR), small heterodimer partner (SHP), inactivates several transcription factors. We previously demonstrated that bile acid represses the expression of gluconeogenic genes, including glucose-6-phosphatase (G6Pase), phosphoenolpyruvate carboxykinase (PEPCK), and fructose-1,6-bisphosphatase (FBP1) in an SHP-dependent ...
Sakamoto Shingo - - 2007
Methyl 1-(3,4-dimethoxyphenyl)-3-(3-ethylvaleryl)-4-hydroxy-6,7,8-trimethoxy-2-naphthoate (S-8921) is a novel inhibitor of the ileal apical sodium-dependent bile acid transporter (ASBT/SLC10A2) developed for the treatment of hypercholesterolemia. The present study investigated the hypocholesterolemic action of S-8921 glucuronide (S-8921G) in rats. The plasma concentration of S-8921G was higher than that of S-8921 after single oral administration ...
Souidi Maâmar - - 2007
In the days following high-dose radiation exposure, damage to small intestinal mucosa is aggravated by changes in the bile acid pool reaching the gut. Intestinal bile acid malabsorption, as described classically, may be associated with altered hepatic bile acid biosynthesis, which was the objective of this work. The activity of ...
Shinka Toshihiro - - 2007
Here we report a simple, sensitive, and accurate method for detecting urinary sulfated tauro- and glyco-bile acids that uses electrospray ionization mass spectrometry. The sulfated tauro- and glycodihydroxycholic acids mainly generated [M-2H](2-) negative ions at m/z 288.6 and m/z 263.6, respectively. These doubly charged ions appeared primarily in samples prepared ...
Gass Jonathan - - 2007
BACKGROUND & AIMS: Conjugated bile acids promote absorption of dietary lipids by solubilizing them in mixed micelles. Bile acids are not considered to facilitate the digestion of other nutrients. METHODS: The effect of conjugated bile acids on the rate of protein hydrolysis by trypsin and chymotrypsin was examined in vitro. ...
Hamilton James P JP Division of Gastroenterology and Hepatology, Department of Medicine, Veterans Affairs Maryland Health Care System and University of Maryland School of Medicine, 22 S. Greene Street, Baltimore, MD 21201, - - 2007
To obtain information on the concentration and spectrum of bile acids in human cecal content, samples were obtained from 19 persons who had died an unnatural death from causes such as trauma, homicide, suicide, or drug overdose. Bile acid concentration was measured via an enzymatic assay for 3alpha-hydroxy bile acids; ...
Alrefai Waddah A - - 2007
Specific transporters expressed in the liver and the intestine, play a critical role in driving the enterohepatic circulation of bile acids. By preserving a circulating pool of bile acids, an important factor influencing bile flow, these transporters are involved in maintaining bile acid and cholesterol homeostasis. Enterohepatic circulation of bile ...
Elias Elwyn - - 2007
The liver is strategically placed to protect the body against a vast array of potentially harmful compounds. The steps involved include phase I metabolism which makes molecules more reactive and phase II reactions which generally enhance solubility in bile or urine. Recent discoveries have shown how regulation of these reactions ...
Keane Megan H - - 2007
The marked deficiency of peroxisomal organelle assembly in the PEX2(-/-) mouse model for Zellweger syndrome provides a unique opportunity to developmentally and biochemically characterize hepatic disease progression and bile acid products. The postnatal survival of homozygous mutants enabled us to evaluate the response to bile acid replenishment in this disease ...
Alrefai Waddah A - - 2007
Bile acid malabsorption has been shown to be associated with diarrhea in cases such as ileal resection Crohn's disease of the ileum, and radiation enteritis. The mechanisms of bile acid-induced diarrhea are not fully understood. Although the induction of colonic chloride secretion in response to bile acids has been extensively ...
Visser Wouter F - - 2007
It is well established that peroxisomes play a crucial role in de novo bile acid biosynthesis. The primary bile acids resulting from peroxisomal beta-oxidation are conjugated to either glycine or taurine in the peroxisomal lumen by a bile acid aminotransferase (BAT). These conjugated bile acids are subsequently secreted into the ...
Zizka Jan - - 2007
OBJECTIVE: To prospectively compare contrast properties of extracelullar (gadobutrol) and hepatospecific (gadoxetic acid) contrast agents in upper abdominal MRI studies. MATERIALS AND METHODS: Standardized (0.1 ml/kg) dose of gadobutrol (56 subjects) and gadoxetic acid (51 subjects) was administered intravenously by MRI-compatible injector at 2 ml/s, followed by 20 ml saline ...
Tradtrantip Lukmanee - - 2007
Phloracetophenone (2,4,6-trihydroxyacetophenone, THA) is a potent choleretic in the bile fistula rat, although the mechanism is unknown. In the present study, we examined how THA enhances bile secretion. Stepwise infusions of THA (1-4 micromol/min) in the isolated perfused rat liver resulted in an immediate and dose-dependent increase in bile flow ...
Dikopoulos N - - 2007
A broad spectrum of hepatobiliary disorders are found in patients with inflammatory bowel diseases. The aim of the present work was to study interactions between gut and liver in experimental rat models of colitis and small bowel inflammation. Colitis was induced either by trinitrobenzene sulphonic acid or dextran sodium sulphate. ...
Zandvliet M M J M - - 2007
BACKGROUND: Irish Wolfhounds frequently have a congenital portosystemic shunt, but a considerable proportion of the 6- to 8-wk-old pups has hyperammonemia in the absence of portosystemic shunting. This hyperammonemia causes no signs and is transient, normalizing at the age of 3-4 months. HYPOTHESIS: Transient hyperammonemia has a metabolic basis in ...
Kim Dockyu - - 2007
Several marine bacterial strains, which were isolated from seawater off the island Dokdo, Korea, were screened to find new bioactive compounds such as antibiotics. Among them, Donghaeana dokdonensis strain DSW-6 was found to produce antibacterial agents, and the agents were then purified and analyzed by LC-MS/MS and 1D- and 2D-NMR ...
Stadlbauer Vanessa - - 2007
Acute-on-chronic liver failure (ACLF) is accompanied by marked intrahepatic cholestasis leading to accumulation of cytotoxic bile acids. Extracorporeal liver support systems efficiently remove bile acids, but their effect on bile acid composition in ACLF is unknown. The aim of the present study was to compare elimination of individual plasma bile ...
Cuesta de Juan Susana - - 2007
Ontogenic changes in the rat bile acid (BA) pool, measured enzymatically and by GC-MS, and expression of enzymes (5alpha-reductase, 5beta-reductase, and cytochrome P450 enzymes Cyp7a1, Cyp8b1, Cyp27 and Cyp3a11), transporters [bile salt export pump, sodium taurocholate-cotransporting polypeptide, apical sodium-dependent bile acid transporter, and organic solute transporter alpha/beta (Ostalpha/Ostbeta)], and nuclear ...
< 2 3 4 5 6 7 8 9 10 11 12 >