The first application of high field NMR spectroscopy (800 MHz for (1)H observation) to human hepatic bile (as opposed to gall bladder bile) is reported. The bile sample used for detailed investigation was from a donor liver with mild fat infiltration, collected during organ retrieval prior to transplantation. In addition, to focus on the detection of bile acids in particular, a bile extract was...

Class separation of methylated free bile acids from bile acids conjugated with taurine and methylglycine was accomplished using a solvent system of 2,2,4-trimethylpentane-absolute ethanol 10:1 (v/v). By developing a silica thin-layer plate two times with solvent in a Brinkmann sandwich tank, the difficult resolution between methyl cholate and methyl glycolithocholate was achieved. Evidence is p...

Administration of large doses of estrogens has been shown to result in decreased conjugation and increased sulfation of bile acids as well as cholestasis. There have been no previous studies on the effects of low doses of estrogens on these parameters of bile acid metabolism. Therefore, rats were given ethinylestradiol, 0.06 to 600 micrograms/kg/day subcutaneously for up to 21 days and the in v...

Bile acids derived from cholesterol and oxysterols derived from cholesterol and bile acid synthesis pathways are signaling molecules that regulate cholesterol homeostasis in mammals. Many nuclear receptors play pivotal roles in the regulation of bile acid and cholesterol metabolism. Bile acids activate the farnesoid X receptor (FXR) to inhibit transcription of the gene for cholesterol 7alpha-hy...

Bile acids as characteristic compounds of human and animal bile are major endogenous products of cholesterol and play very important roles in cholesterol homeostasis, lipid absorption and production of bile flow. At present, bile acids are useful biomarkers and signaling molecules for the diagnosis or treatment of many diseases in clinic. Various analytical methods, from overall to individual, ...

To date, no other studies have examined the seasonal changes in circulating levels of various bile acids in the plasma of wild North American black bears, Ursus americanus. Using gas chromatography, bile acid concentrations were measured in plasma samples obtained during either early or late hibernation, and during summer active periods. Thus, specific compositional changes from individual anim...

The importance of the bile acid structure on mucosal uptake and lymphatic absorption of cholesterol was investigated using four different taurine-conjugated bile acids. Pure synthetic conjugates of a trihydroxy bile acid, taurocholate, and three dihydroxy bile acids, tauroursodeoxycholate, taurochenodeoxycholate, and taurodeoxycholate were used to completely solubilize [14C]cholesterol and pola...

A method has been developed and validated for the determination of the six major conjugated bile acids, cholesterol, and total phospholipids in bile of human subjects previously injected with 4-(14)C-cholesterol. The procedure is designed for use with 5-10 ml of duodenal or T-tube bile and eliminates difficulties associated with existing methods for bile acid determination, in particular the re...

Reports on the microbial degradation of bile-acid conjugates have been mainly limited to observations of hydrolytic cleavage yielding free bile acids. Clostridium spp., Enterococcus spp. (Norman & Grubb, 1955), Bacteroides spp., BiJdobacteria spp. (Drasar & Hill, 1966) and species of rat intestinal bacteria (Dickinson et a/., 1971) were all shown to deconjugate bile-acid conjugates under anaero...

Bile acids, amphipathic end products of cholesterol metabolism, are "good" in the infant because they enhance lipid absorption and thereby promote growth. Bile acids also induce bile flow and biliary lipid secretion. The enterohepatic circulation of bile acids is "bad" in the adult because it downregulates hepatocyte low-density lipoprotein receptor activity and thereby elevates plasma choleste...