Detection of bile acids using optical biosensors based on cholesteric liquid crystal droplets

2021 ◽  
Vol 9 (39) ◽  
pp. 13991-14002
Author(s):  
Buchaiah Gollapelli ◽  
Arun Kumar Tatipamula ◽  
Saikat Dewanjee ◽  
Ramadevi Suguru Pathinti ◽  
Jayalakshmi Vallamkondu
Keyword(s):  
Liquid Crystal ◽  
Bile Acids ◽  
Cholic Acid ◽  
Deoxycholic Acid ◽  
Cholesteric Liquid Crystal ◽  
Optical Biosensors ◽  
Highly Sensitive

We report a novel highly sensitive bile acids (cholic acid and deoxycholic acid) biosensor based on PVA/SC12S-stabilized cholesteric liquid crystal droplets.

Radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid from human serum, with use of 125I-labeled ligands.

1979 ◽  
Vol 25 (2) ◽  
pp. 264-268 ◽  
Author(s):  
O Mäentausta ◽  
O Jänne
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Serum Samples ◽  
Analytical Recovery ◽  
Hepatobiliary Diseases ◽  
Polyethylene Glycol Precipitation ◽  
Free Serum

Abstract We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile acids were separated by polyethylene glycol precipitation (final concentration, 125 g/L). Before radioimmunoassay, 0.1-mL serum samples were precipitated with nine volumes of ethanol, and portions from the supernate were used in the assays. The lowest measurable amounts of the bile acids, expressed as pmol/tube, were: cholic acid conjugates, 2; chenodeoxycholic acid conjugates, 0.5; and deoxycholic acid conjugates. 2. Analytical recovery of bile acids added to bile acid-free serum ranged from 85 to 110%; intra-assay and inter-assay CVs ranged from 3.2 to 5.3% and from 5.3 to 12.2%, respectively. Concentrations (mean +/- SD) of the bile acid conjugates in serum from apparently healthy women and men (in mumol/L) were: cholic acid conjugates, 0.43 +/- 0.17 (n = 126); chenodeoxycholic acid conjugates, 0.47 +/- 0.23 (n = 111); and deoxycholic acid conjugates, 0.33 +/- 0.11 (n = 96). The values for primary bile acids were greatly increased in patients with various hepatobiliary diseases.

scholarly journals Metabolism of Oxo-Bile Acids and Characterization of Recombinant 12α-Hydroxysteroid Dehydrogenases from Bile Acid 7α-Dehydroxylating Human Gut Bacteria

2018 ◽  
Vol 84 (10) ◽  
Author(s):  
Heidi Doden ◽  
Lina A. Sallam ◽  
Saravanan Devendran ◽  
Lindsey Ly ◽  
Greta Doden ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Deoxycholic Acid ◽  
Gut Bacteria ◽  
Dietary Lipids ◽  
Human Gut ◽  
Content Type ◽  
Low Activity

ABSTRACTBile acids are important cholesterol-derived nutrient signaling hormones, synthesized in the liver, that act as detergents to solubilize dietary lipids. Bile acid 7α-dehydroxylating gut bacteria generate the toxic bile acids deoxycholic acid and lithocholic acid from host bile acids. The ability of these bacteria to remove the 7-hydroxyl group is partially dependent on 7α-hydroxysteroid dehydrogenase (HSDH) activity, which reduces 7-oxo-bile acids generated by other gut bacteria. 3α-HSDH has an important enzymatic activity in the bile acid 7α-dehydroxylation pathway. 12α-HSDH activity has been reported for the low-activity bile acid 7α-dehydroxylating bacteriumClostridium leptum; however, this activity has not been reported for high-activity bile acid 7α-dehydroxylating bacteria, such asClostridium scindens,Clostridium hylemonae, andClostridium hiranonis. Here, we demonstrate that these strains express bile acid 12α-HSDH. The recombinant enzymes were characterized from each species and shown to preferentially reduce 12-oxolithocholic acid to deoxycholic acid, with low activity against 12-oxochenodeoxycholic acid and reduced activity when bile acids were conjugated to taurine or glycine. Phylogenetic analysis suggests that 12α-HSDH is widespread amongFirmicutes,Actinobacteriain theCoriobacteriaceaefamily, and human gutArchaea.IMPORTANCE12α-HSDH activity has been established in the medically important bile acid 7α-dehydroxylating bacteriaC. scindens,C. hiranonis, andC. hylemonae. Experiments with recombinant 12α-HSDHs from these strains are consistent with culture-based experiments that show a robust preference for 12-oxolithocholic acid over 12-oxochenodeoxycholic acid. Phylogenetic analysis identified novel members of the gut microbiome encoding 12α-HSDH. Future reengineering of 12α-HSDH enzymes to preferentially oxidize cholic acid may provide a means to industrially produce the therapeutic bile acid ursodeoxycholic acid. In addition, a cholic acid-specific 12α-HSDH expressed in the gut may be useful for the reduction in deoxycholic acid concentration, a bile acid implicated in cancers of the gastrointestinal (GI) tract.

scholarly journals Bile salts of the green turtle Chelonia mydas (L.)

1978 ◽  
Vol 171 (2) ◽  
pp. 409-412 ◽  
Author(s):  
G A D Haslewood ◽  
S Ikawa ◽  
L Tökés ◽  
D Wong
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Green Turtle ◽  
Bile Salts ◽  
Deoxycholic Acid ◽  
Enterohepatic Circulation ◽  
Chelonia Mydas ◽  
Independent Evolution ◽  
Alpha 7

1. Bile salts of the green turtle Chelonia mydas (L.) were analysed as completely as possible. 2. They consist of taurine conjugates of 3 alpha, 7 alpha, 12 alpha, 22 xi-tetrahydroxy-5 beta-cholestan-26-oic acid (tetrahydroxysterocholanic acid) and 3 alpha 12 alpha, 22 xi-trihydroxy-5 beta-cholestan-26-oic acid, with minor amounts of 3 alpha, 7 alpha, 12 alpha-trihydroxy-5beta-cholan-24-oic acid (cholic acid), 3alpha, 12 alpha-dihydroxy-5beta-cholan-24-oic acid (deoxycholic acid) and possibly other bile acids. 3. Cholic acid and deoxycholic acid represent the first known examples of bile acids common to chelonians and other animal forms: they may indicate independent evolution in chelonians to C24 bile acids. 4. The discovery of a 7-deoxy C27 bile acid is the first evidence that C27 bile acids or their conjugates have an enterohepatic circulation.

scholarly journals Preparation of the 3-monosulphates of cholic acid, chenodeoxycholic acid and deoxycholic acid

1976 ◽  
Vol 155 (2) ◽  
pp. 401-404 ◽  
Author(s):  
E S. Haslewood ◽  
G A. D. Haslewood
Keyword(s):  
Liver Disease ◽  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Single Step ◽  
Acid Sulphate

1. The 3-sulphates of cholic, chenodeoxycholic and deoxycholic acids were prepared as crystalline disodium salts. 2. The method described shows that it is possible to prepare specific sulphate esters of polyhydroxy bile acids and to remove protecting acyl groups without removing the sulphate. 3. A study of bile acid sulphate solvolysis showed that none of the usual methods give the original bile acid in major yield in a single step. 4. An understanding of the preparation, properties and methods of solvolysis of bile acid sulphates is basic for investigations of cholestasis and liver disease.

Influence of Deoxycholic Acid Feeding on the Elimination of Cholesterol in Normolipaemic Subjects

1974 ◽  
Vol 47 (5) ◽  
pp. 425-433
Author(s):  
K. Einarsson ◽  
K. Hellström ◽  
M. Kallner
Keyword(s):  
Bile Acid ◽  
Total Synthesis ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Cholesterol Metabolism ◽  
Pool Size ◽  
Faecal Excretion ◽  
The Mean

1. The turnover of [24−14C]cholic acid and [3H]chenodeoxycholic acid and the faecal excretion of neutral steroids were studied in six normolipaemic subjects before and during the ingestion of 1.3–2.6 mmol (0.5–1.0 g) of deoxycholic acid/day. Before the second study the subjects had been fed deoxycholic acid for 2 weeks. 2. The administration of deoxycholic acid did not appear to influence cholesterol metabolism as judged by the absence of change in the serum concentrations and the overall transformation into primary bile acids and neutral faecal steroids. 3. During the deoxycholic acid feeding period the mean total synthesis of bile acids was reduced by about 30%, corresponding to approximately 0.25 mmol (100 mg)/day. In one subject the pool size and in another the synthesis of cholic acid remained unchanged; otherwise the cholic acid pool size and its rate of formation decreased in all subjects. No consistent effects were observed with regard to the turnover of chenodeoxycholic acid. 4. Assuming that the bile acid turnover is equivalent to bile acid excretion then the total amount of cholesterol eliminated as bile acids and neutral faecal steroids averaged between 1.6 and 1.8 mmol/day before and during the administration of deoxycholic acid.

scholarly journals Bile acids inhibit human purinergic receptor P2X4 in a heterologous expression system

2019 ◽  
Vol 151 (6) ◽  
pp. 820-833 ◽  
Author(s):  
Alexandr V. Ilyaskin ◽  
Florian Sure ◽  
Viatcheslav Nesterov ◽  
Silke Haerteis ◽  
Christoph Korbmacher
Keyword(s):  
Ion Channel ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Purinergic Receptor ◽  
Expression System ◽  
Inhibitory Effect ◽  
Xenopus Laevis Oocytes ◽  
Dependent Manner

We recently demonstrated that bile acids, especially tauro-deoxycholic acid (t-DCA), modify the function of the acid-sensing ion channel ASIC1a and other members of the epithelial sodium channel (ENaC)/degenerin (DEG) ion channel family. Surprisingly, ASIC1 shares a high degree of structural similarity with the purinergic receptor P2X4, a nonselective cation channel transiently activated by ATP. P2X4 is abundantly expressed in the apical membrane of bile duct epithelial cells and is therefore exposed to bile acids under physiological conditions. Here, we hypothesize that P2X4 may also be modulated by bile acids and investigate whether t-DCA and other common bile acids affect human P2X4 heterologously expressed in Xenopus laevis oocytes. We find that application of either t-DCA or unconjugated deoxycholic acid (DCA; 250 µM) causes a strong reduction (∼70%) of ATP-activated P2X4-mediated whole-cell currents. The inhibitory effect of 250 µM tauro-chenodeoxycholic acid is less pronounced (∼30%), and 250 µM chenodeoxycholic acid, cholic acid, or tauro-cholic acid did not significantly alter P2X4-mediated currents. t-DCA inhibits P2X4 in a concentration-dependent manner by reducing the efficacy of ATP without significantly changing its affinity. Single-channel patch-clamp recordings provide evidence that t-DCA inhibits P2X4 by stabilizing the channel’s closed state. Using site-directed mutagenesis, we identifiy several amino acid residues within the transmembrane domains of P2X4 that are critically involved in mediating the inhibitory effect of t-DCA on P2X4. Importantly, a W46A mutation converts the inhibitory effect of t-DCA into a stimulatory effect. We conclude that t-DCA directly interacts with P2X4 and decreases ATP-activated P2X4 currents by stabilizing the closed conformation of the channel.

scholarly journals Highly sensitive color-indicating and quantitative biosensor based on cholesteric liquid crystal

2015 ◽  
Vol 6 (12) ◽  
pp. 5033 ◽  
Author(s):  
Yu-Cheng Hsiao ◽  
Yu-Chien Sung ◽  
Mon-Juan Lee ◽  
Wei Lee
Keyword(s):  
Liquid Crystal ◽  
Cholesteric Liquid Crystal ◽  
Highly Sensitive

scholarly journals On the Formation of Deoxycholic Acid from Cholic Acid in the Rabbit. Bile Acids and Steroids 48.

1957 ◽  
Vol 11 ◽  
pp. 421-426 ◽  
Author(s):  
Sven Lindstedt ◽  
Jan Sjövall ◽  
F. Harshbarger ◽  
Arne Magnéli ◽  
Arne Magnéli ◽  
...  
Keyword(s):  
Bile Acids ◽  
Cholic Acid ◽  
Deoxycholic Acid

scholarly journals Clostridium scindensATCC 35704: Integration of Nutritional Requirements, the Complete Genome Sequence, and Global Transcriptional Responses to Bile Acids

2019 ◽  
Vol 85 (7) ◽  
Author(s):  
Saravanan Devendran ◽  
Rachana Shrestha ◽  
João M. P. Alves ◽  
Patricia G. Wolf ◽  
Lindsey Ly ◽  
...  
Keyword(s):  
Bile Acid ◽  
Amino Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Acid Metabolism ◽  
Deoxycholic Acid ◽  
Nutritional Requirements ◽  
Bile Acid Metabolism ◽  
Content Type ◽  
Secondary Bile Acids

ABSTRACTIn the human gut,Clostridium scindensATCC 35704 is a predominant bacterium and one of the major bile acid 7α-dehydroxylating anaerobes. While this organism is well-studied relative to bile acid metabolism, little is known about the basic nutrition and physiology ofC. scindensATCC 35704. To determine the amino acid and vitamin requirements ofC. scindens, the leave-one-out (one amino acid group or vitamin) technique was used to eliminate the nonessential amino acids and vitamins. With this approach, the amino acid tryptophan and three vitamins (riboflavin, pantothenate, and pyridoxal) were found to be required for the growth ofC. scindens. In the newly developed defined medium,C. scindensfermented glucose mainly to ethanol, acetate, formate, and H2.The genome ofC. scindensATCC 35704 was completed through PacBio sequencing. Pathway analysis of the genome sequence coupled with transcriptome sequencing (RNA-Seq) under defined culture conditions revealed consistency with the growth requirements and end products of glucose metabolism. Induction with bile acids revealed complex and differential responses to cholic acid and deoxycholic acid, including the expression of potentially novel bile acid-inducible genes involved in cholic acid metabolism. Responses to toxic deoxycholic acid included expression of genes predicted to be involved in DNA repair, oxidative stress, cell wall maintenance/metabolism, chaperone synthesis, and downregulation of one-third of the genome. These analyses provide valuable insight into the overall biology ofC. scindenswhich may be important in treatment of disease associated with increased colonic secondary bile acids.IMPORTANCEC. scindensis one of a few identified gut bacterial species capable of converting host cholic acid into disease-associated secondary bile acids such as deoxycholic acid. The current work represents an important advance in understanding the nutritional requirements and response to bile acids of the medically important human gut bacterium,C. scindensATCC 35704. A defined medium has been developed which will further the understanding of bile acid metabolism in the context of growth substrates, cofactors, and other metabolites in the vertebrate gut. Analysis of the complete genome supports the nutritional requirements reported here. Genome-wide transcriptomic analysis of gene expression in the presence of cholic acid and deoxycholic acid provides a unique insight into the complex response ofC. scindensATCC 35704 to primary and secondary bile acids. Also revealed are genes with the potential to function in bile acid transport and metabolism.

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