Unsaturated Bile Acids Research Articles

Analysis of metabolic profiles of bile acids in urine using a lipophilic anion exchanger and computerized gas-liquid chromatorgaphy-mass spectrometry

A method is described for quantitative analysis of bile acids in urine. Urine is acidified and bile acids are extracted on an Amberlite XAD-2 column. Bile salts are converted to acids on an Amberlyst A-15 column and are separated into groups of unconjugated, glycine, taurine, monosulfated, and polysulfated conjugates using the lipophilic anion exchanger diethylaminohydroxypropyl Sephadex LH-20 (DEAP-LH-20). After solvolysis and hydrolysis, the deconjugated bile acids are purified on DEAP-LH-20, and are converted to methyl ester trimethylsilyl ether derivatives. Identification and quantitation of the individual bile acids is accomplished by computerized gas-liquid chromatography-mass spectrometry. The daily excretion of bile acids in urine from healthy subjects was 6.4-11 micro moles. The mixture of bile acids was quite complex and differed from that in bile. About 30 bile acids were identified or partially characterized. Three of these were monosubstituted: lithocholic, allolithocholic, and 3beta-hydroxy-5-cholenoic acids. Fourteen disubstituted bile acids included epimers of deoxycholic, allodeoxycholic, chenodeoxycholic, allochenodeoxycholic, and hyodeoxycholic acids. 3alpha-Hydroxy-12-keto-5beta-cholanoic acid was the major ketonic bile acid and 3beta,12alpha-dihydroxy-5-cholenoic acid was the major unsaturated bile acid in this group. Nine trihydroxy bile acids included cholic and allocholic acids, epimers of these compounds, hyocholic acid, and a 1-hydroxylated bile acid tentatively characterized as 1,3,12-trihydroxycholanoic acid. Cholestatic subjects excreted tetrahydroxycholanoates carrying hydroxyl groups in positions 1, 3, 6, 7, 12, or 23. All monohydroxy and the predominant part of dihydroxy bile acids were present in the monosulfate fraction. Exceptions were 3alpha,12beta-dihydroxy- and 3alpha-hydroxy-12-keto-5beta-cholanoic acids, which were found mainly in the glycine conjugate fraction. Most of the trihydroxy bile acids were nonsulfated, and cholic and norcholic acids were the major unconjugated bile acids. The tetrahydroxy bile acids and hyocholic acid were present mainly in the taurine conjugate fraction, while 1,3,12-trihydroxycholanoic acid was predominantly found in the glycine conjugate fraction. Sulfation of trihydroxy bile acids was increased in patients with marked cholestasis. All bile acids in the monosulfate fraction were conjugated and carried the sulfate ester group at C-3. Significant amounts of di- and trisulfates were not found. The results indicate selective mechanisms for sulfation, hydroxylation, and renal elimination of bile acid conjugates. Analysis of metabolic profiles of bile acids in urine may be a useful method in studies of the function of organs involved in bile acid metabolism.

Bile Acids in Bile during Long-term Chenodeoxycholic Acid Treatment

Relative concentrations of conjugated and sulfated bile acids in duodenal bile were measured in 5 patients before and during treatment with 0.50-0.75 g of chenodeoxycholic acid per day for 3-4 months. Lithocholic acid constituted 0.8-3.3% (mean 1.8%) of total conjugated and sulfated bile acids before and 0-5.4% (mean 2.6%) during treatment. Lithocholic acid was the predominant bile acid in the sulfate fraction in three patients and chenodeoxycholic acid in two. Sulfated bile acids constituted less than 1% of total bile acids and did not increase during treatment. Ursodeoxycholic acid, the other major metabolite of chenodeoxycholic acid, was found in higher amounts during therapy. The unsaturated bile acid 3beta-hydroxy-delta5-cholenic acid, which was found exclusively as its sulfate ester, showed a slight fall. The average G/T conjugation ratio rose from 2.2 to 4.5.

The formation of unsaturated bile acids by intestinal bacteria.

Research Article| October 01 1970 The formation of unsaturated bile acids by intestinal bacteria V C Aries; V C Aries Search for other works by this author on: This Site PubMed Google Scholar M J Hill M J Hill Search for other works by this author on: This Site PubMed Google Scholar Biochem J (1970) 119 (5): 37P–38P. https://doi.org/10.1042/bj1190037P Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation V C Aries, M J Hill; The formation of unsaturated bile acids by intestinal bacteria. Biochem J 1 October 1970; 119 (5): 37P–38P. doi: https://doi.org/10.1042/bj1190037P Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Journal Search Advanced Search This content is only available as a PDF. © 1970 The Biochemical Society1970 Article PDF first page preview Close Modal You do not currently have access to this content.

Hydroboration of B-ring unsaturated bile acids

Hydroboration of B-ring unsaturated bile acids

Dehydration of Bile Acids and their Derivatives. X. A Study of the Physical Properties of Various 3α-Hydroxycholenates and their Derivatives, with Special Reference to their Optical Rotatory Dispersions

Abstract Not only ultraviolet and infrared absorption spectra but also optical rotatory dispersions of various unsaturated bile acids were studied, and most of the data were found to be in good agreement with those hitherto obtained concerning the other steroids. The determination of the rotatory dispersion gave the following results: 1) The background rotation of the saturated bile acid is not affected by the introduction of a double bond in ring B, C or D. 2) The introduction of a double bond in ring C or D does not remarkably affect the RD curve of the saturated 3-keto bile acids, while the negative drift of the RD curve given by 3-keto-Δ6-cholenic acid is so very striking that this phenomenon could be utilized for the diagnosis of Δ6-3-keto bile acids (5β). 3) The positive Cotton-effect RD curve given by a saturated 12-keto bile acid is strongly inverted by the introduction of the Δ8(14)-bond, but not by that of the Δ8-bond.

Dehydration of Bile Acids and their Derivatives. IX. Oxidation of Methyl 3α-Acetoxy-Δ7-cholenate with Selenium Dioxide

Abstract Carefully repeated experiments have shown that, contrary to Fieser’s report3), methyl 3α-acetoxy-Δ7-cholenate and some other un-saturated bile acids (5β) listed in Table I give positive results in the selenium dioxide test. This finding was substantiated by the fact that two oxidation products of methyl 3α-acetoxy-Δ7-cholenate were isolated, one of which was proved to be methyl 3α-acetoxy-7ξ, 15ξ-dihydroxy-Δ8(14)-cholenate. It is very interesting to note that, unlike the Δ7-steroids of the 5α-series, not only C7-H, but C15-H of the unsaturated bile acid mentioned above was oxidized with selenium dioxide to give hydroxyl groups, both of which remained without being acetylated under the experimental conditions described.

Unsaturated Bile Acid Derivatives. II. Desulfurizations with Raney Nickel1

Unsaturated Bile Acid Derivatives. II. Desulfurizations with Raney Nickel¹

Unsaturated Bile Acid Derivatives. I. Some Transformation Products from Hyodesoxycholic Acid1

Unsaturated Bile Acid Derivatives. I. Some Transformation Products from Hyodesoxycholic Acid¹