Elevated Levels of Toxic Bile Acids in Serum of Cystic Fibrosis Patients with Mutations Causing Pancreatic Insufficiency.

Hepatobiliary involvement is a hallmark in cystic fibrosis (CF), as the causative CF Transmembrane Conductance Regulator (CFTR) defect is expressed in the biliary tree. However, bile acid (BA) compositions in regard to pancreatic insufficiency, which is present at an early stage in about 85% of CF patients, have not been satisfactorily understood. We assess the pattern of serum BAs in people with CF (pwCF) without CFTR modulator therapy in regard to pancreatic insufficiency and the genotype.

Influence of Verapamil and Cyclosporin A on bile acid metabolism and transport in rat liver slices.

Verapamil (V) is a specific inhibitor of the P-glycoprotein (mdr1) in the hepatocyte canalicular membrane. Cyclosporin A (CsA) as an essential immunosuppressive drug has potentially cholestatic adverse effects on the liver, but increases the expression of mdr1. In precision-cut liver slices from 34- to 40-day-old male Wistar rats 26 individual free and conjugated bile acids (BAs) as markers of hepatic transport and synthesis function were analysed after 4 h incubation with V (100 microM) or CsA (5 microM) in Krebs-Henseleit buffer.

Bile acid transport and metabolism in rat liver slices.

To further characterise precision-cut liver slices from 34- to 40-day-old male rats as an in vitro model for bile acid (BA) metabolism and transport, the effect of the primary BAs cholic (CA, 5 microM) and chenodeoxycholic acid (CDCA, 0.15 and 0.75 microM) as well as of the therapeutically used tauroursodeoxycholic acid (T-UDCA, 5 microM) on BA profiles was investigated.

Influence of ethinyloestradiol propanolsulphonate on serum bile acids in healthy volunteers.

The present work was done to clarify the relevance of altered serum bile acid (BA) profile in healthy women after the administration of the depot oestrogen ethinyloestradiol propanolsulphonate (EES). In the serum of 20 healthy women before and two times after oral EES application, 11 free and 14 taurine- and glycine-conjugated BA were analysed by HPLC with postcolumn derivatisation and fluorescence detection. EES significantly enhanced the total serum BA concentration and that of taurine-conjugated BAs, more pronounced the secondary BAs taurodeoxycholic, tauroursodeoxycholic and taurolithocholic acid.

In vitro investigation of a standardized dried extract of Citrullus colocynthis on liver toxicity in adult rats.

A standardized extract of Citrullus colocynthis used as an oral natural laxative in folk medicine was tested for its influence on liver function parameters in vitro. Cytochrome P450 (CYP) dependent production of reactive oxygen species (ROS) under the influence of Citrullus colocynthis extract was investigated by means of stimulated lipid peroxidation (LPO), H2O2 formation and amplified chemiluminescence in rat liver microsomes. In rat liver 9000 x g supernatants 4 monooxygenase reactions mediated by different CYP forms were measured.