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Zhang B, Jiang X, Yu Y, Cui Y, Wang W, Luo H, Stergiadis S, Wang B. Rumen microbiome-driven insight into bile acid metabolism and host metabolic regulation. THE ISME JOURNAL 2024; 18:wrae098. [PMID: 38836500 PMCID: PMC11193847 DOI: 10.1093/ismejo/wrae098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/20/2024] [Accepted: 06/04/2024] [Indexed: 06/06/2024]
Abstract
Gut microbes play a crucial role in transforming primary bile acids (BAs) into secondary forms, which influence systemic metabolic processes. The rumen, a distinctive and critical microbial habitat in ruminants, boasts a diverse array of microbial species with multifaceted metabolic capabilities. There remains a gap in our understanding of BA metabolism within this ecosystem. Herein, through the analysis of 9371 metagenome-assembled genomes and 329 cultured organisms from the rumen, we identified two enzymes integral to BA metabolism: 3-dehydro-bile acid delta4,6-reductase (baiN) and the bile acid:Na + symporter family (BASS). Both in vitro and in vivo experiments were employed by introducing exogenous BAs. We revealed a transformation of BAs in rumen and found an enzyme cluster, including L-ribulose-5-phosphate 3-epimerase and dihydroorotate dehydrogenase. This cluster, distinct from the previously known BA-inducible operon responsible for 7α-dehydroxylation, suggests a previously unrecognized pathway potentially converting primary BAs into secondary BAs. Moreover, our in vivo experiments indicated that microbial BA administration in the rumen can modulate amino acid and lipid metabolism, with systemic impacts underscored by core secondary BAs and their metabolites. Our study provides insights into the rumen microbiome's role in BA metabolism, revealing a complex microbial pathway for BA biotransformation and its subsequent effect on host metabolic pathways, including those for glucose, amino acids, and lipids. This research not only advances our understanding of microbial BA metabolism but also underscores its wider implications for metabolic regulation, offering opportunities for improving animal and potentially human health.
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Affiliation(s)
- Boyan Zhang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Xianzhe Jiang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Yue Yu
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Yimeng Cui
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Wei Wang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Hailing Luo
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
| | - Sokratis Stergiadis
- Department of Animal Sciences, School of Agriculture Policy and Development, University of Reading, Reading RG6 6EU, United Kingdom
| | - Bing Wang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China
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Panzenboeck U, Andersson U, Hansson M, Sattler W, Meaney S, Björkhem I. On the mechanism of cerebral accumulation of cholestanol in patients with cerebrotendinous xanthomatosis. J Lipid Res 2007; 48:1167-74. [PMID: 17325385 DOI: 10.1194/jlr.m700027-jlr200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The most serious consequence of sterol 27-hydroxylase deficiency in humans [cerebrotendinous xanthomatosis (CTX)] is the development of cholestanol-containing brain xanthomas. The cholestanol in the brain may be derived from the circulation or from 7alpha-hydroxylated intermediates in bile acid synthesis, present at 50- to 250-fold increased levels in plasma. Here, we demonstrate a transfer of 7alpha-hydroxy-4-cholesten-3-one across cultured porcine brain endothelial cells (a model for the blood-brain barrier) that is approximately 100-fold more efficient than the transfer of cholestanol. Furthermore, there was an efficient conversion of 7alpha-hydroxy-4-cholesten-3-one to cholestanol in cultured neuronal and glial cells as well as in monocyte-derived macrophages of human origin. It is concluded that the continuous intracellular production of cholestanol from a bile acid precursor capable of rapidly passing biomembranes, including the blood-brain barrier, is likely to be of major importance for the accumulation of cholestanol in patients with CTX. Such a mechanism also fits well with the observation that treatment with chenodeoxycholic acid, which normalizes the level of the bile acid precursor, results in a reduction of cholestanol-containing xanthomas even in the brain.
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Affiliation(s)
- Ute Panzenboeck
- Institute of Pathophysiology, Center of Molecular Medicine, Medical University of Graz, Graz, Austria, and Division of Clinical Chemistry, Karolinska University Hospital, Karolinska Institutet, Huddinge, Sweden
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von Bahr S, Movin T, Papadogiannakis N, Pikuleva I, Rönnow P, Diczfalusy U, Björkhem I. Mechanism of accumulation of cholesterol and cholestanol in tendons and the role of sterol 27-hydroxylase (CYP27A1). Arterioscler Thromb Vasc Biol 2002; 22:1129-35. [PMID: 12117727 DOI: 10.1161/01.atv.0000022600.61391.a5] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Tendon xanthomas are deposits of lipids and connective tissue commonly found in hypercholesterolemic patients. Macrophages are likely to be responsible for the lipid accumulation. Normolipidemic patients with the rare disease cerebrotendinous xanthomatosis, lacking the enzyme sterol 27-hydroxylase (CYP27A1), develop prominent xanthomas in tendons and brain containing both cholestanol and cholesterol, with a cholestanol:cholesterol ratio higher than that in the circulation. Because of its ability to convert cholesterol into polar metabolites that leave the cells faster, CYP27A1 has been suggested to be an antiatherogenic enzyme. The hypothesis was tested that tendons contain CYP27A1 that may be of importance for the normal efflux of both steroids. METHODS AND RESULTS Western blotting and combined gas chromatography-mass spectrometry showed that human tendons contain significant amounts of CYP27A1 and its product, 27-hydroxycholesterol. Immunohistochemistry showed that CYP27A1 is present in macrophages and tenocytes. The tendons also contained cholestanol, with a cholestanol:cholesterol ratio slightly higher than that in the circulation. Recombinant human CYP27A1, and cultured human macrophages containing this enzyme, had similar activity toward cholesterol and cholestanol. After loading of macrophages with labeled cholesterol and cholestanol, there was an efflux of these steroids in both unmetabolized and 27-oxygenated form, resulting in a significant cellular accumulation of cholestanol compared with cholesterol. CONCLUSION The results are consistent with the possibility that CYP27A1 is of importance for the efflux of both cholesterol and cholestanol from tendons.
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Affiliation(s)
- Sara von Bahr
- Division of Clinical Chemistry, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden
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Herscovitz H, Tietz A. The availability of different sources of cholesterol for bile acid synthesis by cultured chick embryo hepatocytes. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 836:321-34. [PMID: 4041475 DOI: 10.1016/0005-2760(85)90136-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The availability of different sources of cholesterol for bile acid synthesis by cultured chick embryo hepatocytes was studied. Mevalonolactone was taken up by the cells and converted to cholesterol, cholesterol ester and tauroconjugates of bile acids. The addition of mevalonolactone had little effect on the conversion of endogenous cholesterol to taurocholic acid; however, taurochenodeoxycholic acid synthesis was stimulated. 25-30% of the cholesterol synthesized from mevalonolactone was converted to taurochenodeoxycholic, taurocholic and two so-far unidentified bile acids. All bile acids were secreted into the incubation medium. When cholesterol was added as mixed liposomes with phosphatidylcholine, it was taken up by the cells and converted to bile acids. At low concentrations of liposomes, the greater part of the cholesterol which was taken up by the cells was converted to bile acids. At higher concentrations, considerable amounts of cholesterol and cholesterol ester accumulated inside the cells. When mevalonolactone and cholesterol liposomes was added together, both substrates were used simultaneously for bile acids synthesis. HDL cholesterol was the best substrate tested, yielding large amounts of two, so-far, unidentified bile acids (possibly allo-bile acids) and smaller amounts of taurocholic and taurochenodeoxycholic acid. Addition of HDL suppressed the conversion of endogenous cholesterol to taurocholic acid; taurochenodeoxycholic acid synthesis, however, was stimulated.
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Björkhem I, Buchmann MS, Skrede S. On the structural specificity in the regulation of the hydroxymethylglutaryl-CoA reductase and the cholesterol-7 alpha-hydroxylase in rats. Effects of cholestanol feeding. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 835:18-22. [PMID: 3924107 DOI: 10.1016/0005-2760(85)90024-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The effect of feeding 2% cholestanol or cholesterol on cholesterol-7 alpha-hydroxylase activity and hydroxymethylglutaryl (HMG)-CoA reductase activity was studied in rats. The rate of 7 alpha-hydroxylation of a trace amount of labelled cholesterol increased by about 80% after the cholestanol feeding, whereas the 7 alpha-hydroxylation of endogenous microsomal cholesterol increased by about 40%. The latter conversion was measured with an accurate technique based on isotope dilution-mass spectrometry. After cholesterol feeding, the corresponding figures were about 50 and 60%, respectively. The cholestanol feeding had no significant effect on the HMG-CoA reductase activity, whereas the cholesterol feeding decreased the activity by about 80%. From the results obtained, it is concluded that the increased 7 alpha-hydroxylation observed after cholesterol feeding can not be explained only by a simple expansion of the substrate pool. The similar effect of both cholesterol and cholestanol on the cholesterol 7 alpha-hydroxylase activity and the diverging effect on the HMG-CoA reductase activity show that there is no coupling between cholesterol synthesis and degradation under the conditions employed. The lack of effect of cholestanol on the HMG-CoA reductase activity indicates a high structural specificity of the receptor involved in regulation of the enzyme. If a receptor mechanism is involved in the stimulation of the cholesterol-7 alpha-hydroxylase by cholesterol and cholestanol, these receptor(s) must be different from those involved in the regulation of the HMG-CoA reductase.
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Shefer S, Hauser S, Salen G, Zaki FG, Bullock J, Salgado E, Shevitz J. Comparative effects of cholestanol and cholesterol on hepatic sterol and bile acid metabolism in the rat. J Clin Invest 1984; 74:1773-81. [PMID: 6501569 PMCID: PMC425357 DOI: 10.1172/jci111596] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Large amounts of cholestanol, the 5 alpha-dihydro derivative of cholesterol are found in tissues of patients with the rare inherited sterol storage disease cerebrotendinous xanthomatosis. Although small amounts of cholestanol are present in virtually every tissue of normal man, little is known about its metabolism and effect on cholesterol and bile acid formation. The purpose of this study is to investigate the absorption and metabolism of cholestanol and its early effects on hepatic morphology and on the rate-limiting enzymes of cholesterol and bile acid biosynthesis. After 2 wk on a diet supplemented with 2% cholestanol, total liver sterol content increased by 48% (3.26 vs. 2.20 mg/g), and resulted in a significant rise in hepatic cholestanol concentration to 1.4 mg/g. However, cholestanol was less efficiently absorbed from the intestine than cholesterol and interfered with cholesterol absorption. Furthermore, hepatic hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase activity rose 2.6-fold (from 150.3 to 397.0 pmol/mg per min) during cholestanol feeding, and was associated with a marked proliferation of the smooth endoplasmic reticulum of the centrilobular areas. In addition, significant amounts of allocholic acid (16%) and allochenodeoxycholic acid (5%) were formed from cholestanol and excreted in the bile. These results show that cholestanol is absorbed from the intestine, interferes with cholesterol absorption, and is deposited in the liver. However, in contrast to cholesterol, cholestanol feeding was associated with a marked elevation of HMG-CoA reductase activity. Thus, despite structural similarity between cholesterol and its 5 alpha-saturated derivative, cholestanol does not exert feedback inhibition on hepatic cholesterol biosynthesis.
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Björkhem I, Buchmann MS, Skrede S. Isolation of 5α-cholestane-3β,7α-diol from bile of patients with cerebrotendinous xanthomatosis. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0005-2760(83)90010-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Aringer L, Nordström L. Chromatographic properties and mass spectrometric fragmentation of dioxygenated C27-, C28-, C29-steroids. ACTA ACUST UNITED AC 1981. [DOI: 10.1002/bms.1200080502] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Golf SW, Graef V. Purification and properties of a NAD: 3 alpha-hydroxy-5 alpha-pregnan-20-one-oxidoreductase from rat liver microsomes. Steroids 1980; 36:167-76. [PMID: 6934632 DOI: 10.1016/0039-128x(80)90016-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
From rat liver microsomes a NAD: 3 alpha-hydroxy-5 alpha-pregnan-20-one oxidoreductase was isolated and purified up to a specific activity of 73 nmol/min . mg by affinity chromatography and DEAE-cellulose chromatography. Various Km-values have been determined. The enzyme exhibits highest affinity for 5 alpha-pregnane-3,20-dione and NADH. The 3-oxo group of 5 alpha-dihydrocortisone (17,21-dihydroxy-5 alpha-pregnane-3,11,20-trione) was not reduced by the purified enzyme preparation and NADH and no dehydrogenation with NAD was observed of 3 alpha,11 beta,17,21-tetrahydroxy-5 alpha-pregnan-20-one. The optimal pH for the hydrogenation of th 3-oxo group was at pH 5.3 and for the dehydrogenation at pH 8.9. Disc gel electrophoresis in presence of 0.1% sodium dodecylsulfate yielded a homogeneous preparation.
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Abstract
The metabolism of bile acids in man is disturbed under the conditions of cholestasis. Besides of the main bile acids atypical bile acids can be found, which are mainly eliminated by renal excretion as sulphate esters and glucuronides. The pattern of urinary bile acids up to now renders no conclusions with respect to the underlying disease, although intrahepatic cholestasis seems to be in some way connected with disturbances in the metabolism of 3 beta-hydroxy-5-cholenoic acid, a bile acid, which exerts cholestatic effects by itself. The metabolites to be found seem to reflect a derepression of a genotypical synthesis program, which is not phenotypically apparent in healthy adults, but which may have been active during prenatal developmental stages of the liver.
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Shaw R, Elliott WH. Competitive inhibitors of rabbit hepatic microsomal 12 alpha-steroid hydroxylase. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(18)50301-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Golf SW, Graef V. Isolation of a NAD:3 beta(alpha)-hydroxy-5 beta-androstane dehydrogenase from rat liver microsomes. JOURNAL OF STEROID BIOCHEMISTRY 1979; 10:201-5. [PMID: 513733 DOI: 10.1016/0022-4731(79)90236-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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7-Hydroxylation of 3-oxygenated C27-, C28-, and C29-steroids in rat liver 18,000 g supernate. J Lipid Res 1978. [DOI: 10.1016/s0022-2275(20)40676-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Bile acids. LI. Formation of 12α-hydroxyl derivatives and companions from 5α-sterols by rabbit liver microsomes. J Lipid Res 1976. [DOI: 10.1016/s0022-2275(20)34923-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Golf SW, Graef V. Isolation of a 3-equatorial-hydroxysteroid dehydrogenase from rat liver microsomes. FEBS Lett 1976; 64:315-8. [PMID: 6329 DOI: 10.1016/0014-5793(76)80318-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Ali SS, Farhat H, Elliott WH. Bile acids. XLIX. Allocholic acid, the major bile acid of Uromastix hardwickii. J Lipid Res 1976. [DOI: 10.1016/s0022-2275(20)37011-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Ali SS, Elliott WH. Bile acids. XLVII. 12alpha-Hydroxylation of precursors of allo bile acids by rabbit liver microsomes. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 409:249-57. [PMID: 65 DOI: 10.1016/0005-2760(75)90159-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Rabbit liver microsomal preparations fortified with 0.1 mM NADPH effectively promote hydroxylation of [3beta-3H]- or [24-14C]allochenodeoxycholic acid or [5alpha,6alpha-3H2]5alpha-cholestane-3alpha,7alpha-diol to their respective 12alpha-hydroxyl derivatives in yields of about 25 or 65% in 60 min. Minor amounts of other products are formed from the diol. The requirements for activity of rabbit liver microsomal 12alpha-hydroxylase resemble those of rat liver microsomes. Of a number of enzyme inhibitors studied only p-chloromercuribenzoate demonstrated a marked ability to inhibit the reaction with either tritiated substrate. There was no difference in the quantity of product produced from the tritiated acid or the 14C-labeled acid. No clear sex difference was found in activity of the enzyme, nor was an appreciable difference noted in activity of the enzyme between mature and immature animals.
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Björkhem I, Danielsson H, Wikvall K. Reduction of C19-, C21-, C24-, and C27-3-oxosteroids by rat-liver microsomes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1973; 36:8-15. [PMID: 4147367 DOI: 10.1111/j.1432-1033.1973.tb02878.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Noll BW, Doisy E, Elliott WH. Bile acids. XXXVIII. Conversion of 5α-cholestane-3β,7α-diol to allo bile acids by the rat. J Lipid Res 1973. [DOI: 10.1016/s0022-2275(20)36870-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Soloway RD, Hofmann AF, Thomas PJ, Schoenfield LJ, Klein PD. Triketocholanoic (dehydrocholic) acid. Hepatic metabolism and effect on bile flow and biliary lipid secretion in man. J Clin Invest 1973; 52:715-24. [PMID: 4685091 PMCID: PMC302310 DOI: 10.1172/jci107233] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
[24-(14)C]Dehydrocholic acid (triketo-5-beta-cholanoic acid) was synthesized from [24-(14)C]cholic acid, mixed with 200 mg of carrier, and administered intravenously to two patients with indwelling T tubes designed to permit bile sampling without interruption of the enterohepatic circulation. More than 80% of infused radioactivity was excreted rapidly in bile as glycine- and taurine-conjugated bile acids. Radioactive products were identified, after deconjugation, as partially or completely reduced derivatives of dehydrocholic acid. By mass spectrometry, as well as chromatography, the major metabolite (about 70%) was a dihydroxy monoketo bile acid (3alpha,7alpha-dihydroxy-12-keto-5beta-cholanoic acid); a second metabolite (about 20%) was a monohydroxy diketo acid (3alpha-hydroxy-7,12-di-keto-5beta-cholanoic acid); and about 10% of radioactivity was present as cholic acid. Reduction appeared to have been sequential (3 position, then 7 position, and then 12 position) and stereospecific (only alpha epimers were recovered). Bile flow, expressed as the ratio of bile flow to bile acid excretion, was increased after dehydrocholic acid administration. It was speculated that the hydroxy keto metabolites are hydrocholeretics. The proportion of cholesterol to lecithin and bile acids did not change significantly after dehydrocholic acid administration. In vitro studies showed that the hydroxy keto metabolites dispersed lecithin poorly compared to cholate; however, mixtures of cholate and either metabolite had dispersant properties similar to those of cholate alone, provided the ratio of metabolite to cholate remained below a value characteristic for each metabolite. These experiments disclose a new metabolic pathway in man, provide further insight into the hydrocholeresis induced by keto bile acids, and indicate the striking change in pharmacologic and physical properties caused by replacement of hydroxyl by a keto substituent in the bile acid molecule.
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Noll BW, Ziller SA, Doisy E, Elliott WH. Bile acids. XXXVII. Identification of the 3β isomers of allocholic and allochenodeoxycholic acids as metabolites of 5α-cholestanol in the rat. J Lipid Res 1973. [DOI: 10.1016/s0022-2275(20)36911-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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