Solubilisation of dipalmitoylphosphatidylcholine bilayers by sodium taurocholate: A model to study the stability of liposomes in the gastrointestinal tract and their mechanism of interaction with a model bile salt

2009 ◽  
Vol 71 (2) ◽  
pp. 346-355 ◽  
Author(s):  
Karine Andrieux ◽  
Laura Forte ◽  
Sylviane Lesieur ◽  
Maité Paternostre ◽  
Michel Ollivon ◽  
...  
2012 ◽  
Vol 29 (Special Issue) ◽  
pp. S30-S35 ◽  
Author(s):  
Š. Horáčková ◽  
K. Žaludová ◽  
M. Plocková

The cell survival in the digestive tract is one of the main criteria required for the probiotics. The aim of this study was to evaluate the stability of the selected lactobacilli (Lactobacillus acidophilus CCDM 151; L. casei CCDM 198; L. rhamnosus CCDM 150, and L. fermentum ST 68) in conditions simulating those in the gastrointestinal tract as compared to the commercial probiotic strain Lactobacillus casei LAFTI L-26. The growth of lactobacilli decreased both after 2 h and 4 h incubation in MRS media with increasing concentration of bile salt but all lactobacilli had the ability to adapt in the environment of bile salt. Great differences in viability were detected between the isolated cells in the stomach simulating conditions. L. casei LAFTI L-26 and L. acidophilus CCDM 151 were most stable, L. rhamnosus CCDM 150 did not survive under these conditions. Milk revealed a strong protective influence on the viability of all lactobacilli in the stomach simulating conditions. The conditions existing in the small intestine did not influence the cell viability. Differences in autoaggregation were also observed.


2010 ◽  
Vol 299 (2) ◽  
pp. G320-G328 ◽  
Author(s):  
Claudia Stross ◽  
Angelika Helmer ◽  
Katrin Weissenberger ◽  
Boris Görg ◽  
Verena Keitel ◽  
...  

Bile salts influence signaling and metabolic pathways. In hepatocytes, the sodium taurocholate cotransporting polypeptide (Ntcp) is a major determinant of intracellular bile salt levels. Short-term downregulation of Ntcp is not well characterized to date. FLAG and enhanced green fluorescent protein (EGFP) tags were cloned to the extra- and intracellular termini of Ntcp. Endocytosis of Ntcp in transfected HepG2 cells was visualized by fluorescence of EGFP, and membrane surface expression of Ntcp was quantified by flow cytometry with fluorochrome-labeled FLAG antibodies. Activation of protein kinase C (PKC) by phorbolester or thymeleatoxin an activator of Ca2+-dependent conventional PKCs (cPKCs), induced endocytosis of Ntcp, whereas the Na+-K+-ATPase remained in the plasma membrane. The PKC inhibitor BIM I and the cPKC-selective inhibitor Gö6976 abolished PMA-induced endocytosis. Because of this internalization, cell surface expression of Ntcp was reduced by 36 ± 7%, bile salt uptake was decreased by 25%, and taurolithocholate sulfate-induced cell toxicity was prevented. In conclusion, Ca2+-dependent PKCs induce vesicular retrieval of Ntcp, thereby reducing bile salt uptake. This mechanism may protect hepatocytes from toxic intracellular bile salt concentrations.


1965 ◽  
Vol 208 (2) ◽  
pp. 363-369 ◽  
Author(s):  
M. R. Playoust ◽  
Leon Lack ◽  
I. M. Weiner

The efficiency of intestinal absorption of bile salts was evaluated by studying the rate of disappearance of radioactivity from the bile of dogs after the intravenous administration of sodium taurocholate-24-C14. Bile was sampled through an indwelling tube in the gall bladder. One day after a high-fat meal normal dogs retained 48% of the radioactivity; dogs with resection of the jejunum retained 48%, whereas those with resection of the ileum retained only 3% in the bile. This is consistent with previous observations that the ileum is the site of bile salt absorption in vitro and in anesthetized animals. Animals with resection of the ileum exhibited significant steatorrhea; however, three-fourths of the ingested fat was absorbed in spite of almost complete failure to absorb bile salts. This indicates that fat and bile salts are not normally absorbed together. Elimination of enterohepatic circulation of bile salts by resection of the ileum contributes to the observed steatorrhea.


Author(s):  
Ivelin Pantchev ◽  
Goritsa Rakleova ◽  
Atanas Atanassov

Abstract The research community is deeply convinced that RNA is unstable in the environment. Its roots rise from numerous failed attempts to isolate functional cellular RNA molecules. Further support had originated from the fast turnover of RNA in the cells. The situation changed recently with the discovery that externally applied dsRNA can produce targeted gene silencing in plant-feeding insects. First results have demonstrated that external dsRNA can successfully pass the insect gastrointestinal tract and reach its final destination within the body cells. This was somewhat unexpected and sparked new interest in RNA stability in the environment and its fate in the insect organism. In this brief review we make an attempt to summarize current knowledge and to propose a model of how dsRNA can perform its function under these settings.


2019 ◽  
Vol 20 (5) ◽  
pp. 377-389 ◽  
Author(s):  
Xiaoyang Lu ◽  
Lin Liu ◽  
Wenya Shan ◽  
Limin Kong ◽  
Na Chen ◽  
...  

Background:Sodium Taurocholate Co-transporting Polypeptide (NTCP) and Bile Salt Export Pump (BSEP) play significant roles as membrane transporters because of their presence in the enterohepatic circulation of bile salts. They have emerged as promising drug targets in related liver disease.Methods:We reviewed the literature published over the last 20 years with a focus on NTCP and BSEP.Results:This review summarizes the current perception about structure, function, genetic variation, and regulation of NTCP and BSEP, highlights the effects of their defects in some hepatic disorders, and discusses the application prospect of new transcriptional activators in liver diseases.Conclusion:NTCP and BSEP are important proteins for transportation and homeostasis maintenance of bile acids. Further research is needed to develop new models for determining the structure-function relationship of bile acid transporters and screening for substrates and inhibitors, as well as to gain more information about the regulatory genetic mechanisms involved in the processes of liver injury.


1988 ◽  
Vol 51 (4) ◽  
pp. 310-313 ◽  
Author(s):  
H. L. PAN ◽  
C. W. DILL ◽  
E. S. ALFORD ◽  
S. L. DILL ◽  
C. A. BAILEY ◽  
...  

Time-temperature relationships for heat-inactivation of the bile salt-stimulated lipase activity were compared in whole human milk and in the same product fortified to 9 mM/ml with sodium taurocholate. Heat treatments were varied from 45 to 70°C for times ranging from 15s to 40 min. Enzyme activity was more heat stable in human milk fortified with taurocholate than in control samples. The temperature required for the onset of heat inactivation at 30-min holding time was increased from 45°C for control samples to 60°C following addition of taurocholate. A temperature differential of approximately 12°C was required in the fortified milks to produce inactivation equivalent to that observed in the control milks over the heating range studied.


1976 ◽  
Vol 231 (6) ◽  
pp. 1875-1878 ◽  
Author(s):  
Y Delage ◽  
M Dumont ◽  
S Erlinger

The effect on sulfobromophathalein transport maximum (Tm) and biliary lipid secretion of sodium glyco-24,25-dihydrofusicate, a micelle-forming compound secreted into bile, has been studied in the hamster and compared to that of a physiological bile salt, sodium taurocholate. Biliary phospholipid and cholesterol secretion increased both during glycodihydrofusidate and taurocholate administration, an observation which suggest that both compounds increased th biliary secretion of micelle-forming compounds. In contrast, only taurocholate increased sulfobromophthalein Tm into bile, while glycodihydrofusidate administration decreased it. This observation suggests that the increase in sulfobromophthalein Tm observed during taurocholate administration is not the result of micellar sequestration. It could rather be the consequence of a specific effect of bile salts on the dye transport system.


Foods ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 505 ◽  
Author(s):  
Gabriel Oliveira ◽  
Urszula Tylewicz ◽  
Marco Dalla Rosa ◽  
Thomas Andlid ◽  
Marie Alminger

Berry fruits, such as strawberries and blueberries, are rich sources of anthocyanins. Several studies have been made on the impact of non-thermal treatments on safety, shelf-life and nutritional characteristics of such products, but the effects of these processes on anthocyanin stability during digestion in the gastrointestinal tract are still not completely clear. The aim of this study was to assess the recovery of anthocyanins after simulated gastrointestinal digestion of (1) strawberry samples, pre-treated with pulsed electric field (PEF) at 100 or 200 V·cm−1, prior to osmotic dehydration (OD), and (2) blueberry samples coated with chitosan and procyanidin. After digestion, a significantly higher content of cyanidin-3-O-glucoside and malvidin-3-O-glucoside was quantified by LC-MS/MS in processed strawberry and blueberry samples, compared with the controls. The highest recovery of cyanidin-3-O-glucoside was detected in digested strawberry samples osmotically dehydrated with trehalose. The recovery of malvidin-3-O-glucoside was highest in digested blueberries coated with chitosan and stored for 14 days, compared with untreated samples or samples coated with chitosan and procyanidin. Our study shows the potential of mild PEF treatments combined with OD, or the use of edible coating, to obtain shelf-stable products without substantially affecting the composition or the stability of anthocyanins during digestion in the upper gastrointestinal tract.


Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 986
Author(s):  
Monique D. Appelman ◽  
Marion J.D. Robin ◽  
Esther W.M. Vogels ◽  
Christie Wolzak ◽  
Winnie G. Vos ◽  
...  

The sodium taurocholate cotransporting polypeptide (NTCP) is expressed at the basolateral membrane of hepatocytes, where it mediates the uptake of conjugated bile acids and forms the hepatocyte entry receptor for the hepatitis B and D virus. Here, we aimed to identify novel protein–protein interactions that could play a role in the regulation of NTCP. To this end, NTCP was precipitated from HA-tagged hNTCP-expressing HepG2 cells, and chloride channel CLIC-like 1 (CLCC1) and stomatin were identified as interacting proteins by mass spectrometry. Interaction was confirmed by co-immunoprecipitation. NTCP, CLCC1 and stomatin were found at the plasma membrane in lipid rafts, as demonstrated by a combination of immunofluorescence, cell surface biotinylation and isolation of detergent-resistant membranes. Neither CLCC1 overexpression nor its knockdown had an effect on NTCP function. However, both stomatin overexpression and knockdown increased NTCP-mediated taurocholate uptake while NTCP abundance at the plasma membrane was only increased in stomatin depleted cells. These findings identify stomatin as an interactor of NTCP and show that the interaction modulates bile salt transport.


2015 ◽  
Vol 17 (30) ◽  
pp. 19977-19990 ◽  
Author(s):  
Arpita Roy ◽  
Niloy Kundu ◽  
Debasis Banik ◽  
Jagannath Kuchlyan ◽  
Nilmoni Sarkar

The triblock copolymer of the type (PEO)20–(PPO)70–(PEO)20 (P123) forms a mixed supramolecular aggregate with different bile salts, sodium deoxycholate (NaDC) and sodium taurocholate (NaTC), having different hydrophobicity.


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