Abnormally low ratio of cholic acid to chenodeoxycholic acid due to a deficiency of 3-oxo-delta4-steroid 5beta-reductase.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The effect of dietary fat or cholesterol and cholic acid on the rate of synthesis of rat liver glucose-6-P dehydrogenase was measured by isolating hepatocytes from the livers of rats fed diets containing various amounts and types of lipid. Hepatocyte proteins were labeled with [3H]leucine and glucose-6-P dehydrogenase was immunoprecipitated with a specific antiserum. The immunoprecipitates were electrophoresed on sodium dodecyl sulfate-polyacrylamide gels and the radioactivity in the glucose-6-P dehydrogenase subunit was used to calculate the relative rate of synthesis of the enzyme. It is concluded that the activity of glucose-6-P dehydrogenase is primarily regulated by alterations in the rate at which the enzyme is synthesized. Dietary fat may decrease the rate of degradation of glucose-6-P dehydrogenase.
BACKGROUND & AIMS: Qualitative and quantitative changes in intralumenal bile acid composition may alter cholesterol absorption and synthesis and low-density lipoprotein (LDL) receptor expression. The role of cholic acid (CA) in cholesterol absorption in humans remains unclear and, thus, was examined in the current study. METHODS: In a crossover design outpatient study, 12 adults aged 24-36 years took 15 mg/kg/day (CA) or no bile acid supplement (control) while being fed a controlled diet (AHA heart-healthy diet). A liquid meal of defined composition was given on day 14 of the diet, and lumenal samples were collected. Thereafter, cholesterol absorption and cholesterol fractional synthetic rate (FSR) were assessed by stable isotopic methods from days 16 to 20. RESULTS: With CA treatment, bile was enriched significantly with CA (P < 0.0004) to 60.2% +/- 2.4% (mean +/- SEM) compared with 43.3% +/- 2.4% for controls. CA plus diet treatment significantly increased (P = 0.013) cholesterol absorption (72.6% +/- 2.9%) compared with diet treatment alone (60.4% +/- 2.9%). Percentage micellar cholesterol was increased by CA plus diet treatment vs. diet alone after meal ingestion (P = 0.004). Plasma total and high-density lipoprotein (HDL) and LDL cholesterol was unchanged with CA treatment. CONCLUSIONS: Thus, enrichment in lumenal bile with CA results in an increase in cholesterol absorption, an effect potentially mediated by enhanced cholesterol solubilization in micelles.
Explore the source record for details and available documents.
[structure: see text] The fluorescent photoinduced electron transfer (PET) chemosensors 1-3 were synthesized from cholic acid. 1 and 2 containing amidothiourea groups as anion receptive sites demonstrated much higher affinity toward anions than 3 containing traditional thiourea H-bond donating group. Comparative studies on their binding affinity toward carboxylates, dihydrogen phosphate, and halides revealed that the amidothiourea moiety on the C17 side chain could work cooperatively with H-bond donating groups on C7 and C12 to bind spherical halogen anions. An unexpected specific fluorescence enhancement of 1 by coordinating bromide ion was observed.
By measuring total faecal radioactivity, correlated to 24-hour enterohepatic circulation, following i.v. administration of 14C-cholic acid, bile salt malabsorption was evaluated before and/or after surgery in 80 patients with Crohn's disease localized to the ileum and/or the colon and the results related to the length of ileum diseased or resected. Before operation bile salt malabsorption was observed only in patients with inflammation of the terminal ileum, but no significant correlation was found between bile salt excretion and the extent of ileal disease. In patients subjected to ileal resection with sacrifice of the ileocaecal valve, bile salt malabsorption correlated strongly to the length of ileum resected. This correlation was about the same in ileostomy patients and in patients subjected to restorative operation. We concluded that determination of 14C in faeces is a more sensitive test than the Schilling test and the faecal fat excretion test in reflecting ileal dysfunction, at least in patients with ileal resections.
Explore the source record for details and available documents.
The clearance profiles of intravenously injected tracer doses of radioactively labelled cholic acid were investigated in healthy dogs, dogs with a congenital portosystemic shunt and dogs with cholestasis. The rate constants and residual plasma activity were significantly different in the healthy and diseased dogs, but it was not possible to differentiate between the dogs with portosystemic shunting and cholestasis because the results were determined not only by factors involved in plasma bile acid clearance but also by the enterohepatic circulation.
A stable isotope dilution method is described that allows measurement of cholic acid (CA) kinetics, that is, pool size, fractional turnover rate (FTR), and synthesis rate in mice, rats, and humans. Decay of administered [2,2,4,4-2H4]CA enrichment was measured in time in 50-microl plasma samples by gas-liquid chromatography/electron capture negative chemical ionization-mass spectrometry, applying the pentafluorobenzyl-trimethylsilyl derivative. The kinetic data expressed species-dependent differences. The CA pool sizes were 16.8 +/- 2.1, 10.6 +/- 1.2, and 2.4 +/- 0.7 micromol/100 g body weight for mice, rats, and humans, respectively. The FTR values were 0.44 +/- 0.03, 0.88 +/- 0.10, and 0.46 +/- 0.14 per day for mice, rats, and humans. The corresponding synthesis rates were 7.3 +/- 1.6, 9.3 +/- 0.1, and 1.0 +/- 0.2 micromol/100 g body weight per day. The human data agreed well with literature data obtained by conventional isotope dilution techniques. For rats and mice these are the first reported isotope dilution data. The method was validated by confirmation of isotopic equilibrium between biliary CA and plasma CA in the rat. Its applicability was demonstrated by the observation of increased CA FTR and CA synthesis rate in rats fed cholestyramine, which is known to increase fecal bile acid excretion. The presented stable isotope dilution method enables the determination of CA kinetic parameters in small plasma samples. The method can be applied in unanesthetized rodents with an intact enterohepatic circulation and may also be valuable when studying the development of human neonatal bile acid kinetics.
Two proteins, in previous work labeled by affinity markers derived from taurocholic acid, were purified and partially sequenced. Antibodies were raised against purified proteins, and cross-reactions were carefully checked. The influence of these antibodies upon taurocholic acid import into vesicles from rat liver plasma membranes was measured, and showed a distinct inhibition of transport in the case of the 54 kD protein.
Explore the source record for details and available documents.
The crystal structures of inclusion compounds of cholic acid (CA) with 28 monosubstituted benzenes have been systematically investigated. All of the crystals belong to the monoclinic space group P2(1) and have bilayer structures with one-dimensional molecular channels that can include guest compounds. They are classified into four types of host frameworks that depend on the conformations and stacking modes of the host compound. The host frameworks and the host-guest ratios depend primarily on the molecular volumes of the guest compounds. The packing coefficient of the host cavity (PCcavity), which is the volume ratio of the guest compound to the host cavity, is used to clarify the relationship between the guest volume and isomerization of the host frameworks. The value of PCcavity, for stable inclusion compounds lies in the range of 55-70%. Compounds out of this range induce isomerization of the host frameworks. The packing coefficients of other host-guest compounds, in which the guest components are included in the host cavities through steric dimensions and van der Waals forces, are also in this range. These results indicate that PCcavity is a useful parameter correlation for guest recognition and isomerization of the host frameworks.
Bile salt absorption, as determined by the faecal excretion in i.v. injected 14C-cholic acid (FBS) was studied in 13 ileostomy patients before and after conversion to Kock's continent ileostomy reservoir. The result was compared with that obtained in 8 ileostomy patients in whom about 50 cm of the terminal ileum has also been removed. As compared with 16 healthy controls, FBS was moderately increased in the conventional ileostomy patients, but still within normal limits. After conversion to ileostomy reservoir all patients had pathological FBS, although less severe than in the ileostomy patients with ileal resection. Bacterial contamination probably contributes more than the structural mucosal changes to the bile malabsorption in the pouch, whereas reduced mucosal surface and short small-intestinal transit time are the main causes of malabsorption in ileostomy patients in whom an appreciable amount of the terminal ileum has been resected.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The results reported in this paper regard the setting up of a polymeric membrane ISE that is selective for cholic acids (CA) and able to work in a flow system, especially in flow injection analysis (FIA), based on the exchanger (tetrakisdecylammoniumcholate, TDACh), which has proved effective, is of very simple but suitable structure and is above all easy to synthesise starting from commercially available chemicals. A complete analytical characterisation of the sensor was performed working both in batch conditions and in FIA, using in the latter case a 'wall jet' type of flow cell. The response toward different bile acid sodium salts such as the CA, deoxycholic (DCA), chenodeoxycholic (CDCA), ursodeoxycholic (UDCA), taurocholic (TCA) sodium salts was checked. The application to the analysis of different commercial drugs by FIA was also performed to determine the UDCA or CDCA acid content of several pharmaceutical formulations. Lastly, a preliminary study is presented concerning the use of the investigated electrochemical sensor as high performance liquid chromatography (HPLC) detector.
Explore the source record for details and available documents.