Barth A, Bernst M
Institute of Pharmacology and Toxicology, Friedrich Schiller University Jena, Germany.
Exp Toxicol Pathol. 1992 Dec;44(7):399-405. doi: 10.1016/S0940-2993(11)80175-2.
Bile acids were found to be effective antioxidants in bile and intestine. The influence of different bile acids on the NADPH-Fe(++)-stimulated lipid peroxidation (LPO) and cytochrome P-450 dependent hydrogen peroxide production (H2O2) in rat liver microsomes was investigated in vitro. LPO was determined as production of thiobarbituric acid reactants (TBAR). Different tri-, di- and monohydroxylated bile acids and cholesterol were given to the incubation mixture in concentrations ranging from 10(-5) to 10(-3) M. Sodium salts of cholic, tauroglycocholic and deoxycholic acids as well as cheno-deoxycholic, ursodeoxycholic, lithocholic acids and cholesterol did not alter the microsomal production of TBAR. H2O2 formation was significantly decreased by sodium deoxycholate whereas cholesterol increased H2O2 production up to 4 times. These results show that bile acids were not able to protect microsomal membrane lipids against peroxidative damage. Cholesterol mediated H2O2 formation as a source of hydroxyl radicals had no toxic effect concerning LPO, TBAR were not enhanced significantly.
