Effect of bile acids on the binding of drugs and dyes to human albumin

Abstract

Chenodeoxycholic, cholic, deoxycholic and taurodeoxycholic acids were found to inhibit the binding of 2-(4'-hydroxybenzeneazo)benzoic acid, methyl orange, sulphadimethoxine and warfarin to human albumin. In addition, glycodeoxycholic acid inhibited the binding of sulphadimethoxine and warfarin. In contrast, these bile acids did not inhibit the binding of phenylbutazone. The extent of displacement was in the rank order of: dihydroxy acids (chenodeoxycholic and deoxycholic) greater than trihydroxy acid (cholic) greater than conjugates (glycodeoxycholic and taurodeoxycholic). Thus the introduction of polar groups into the steroid nucleus of bile acids reduces their effectiveness as binding inhibitors. Displacement was usually accompanied by a decrease in the apparent association constant which suggests that the mechanism of displacement may be competitive.

Role of the conformational flexibility of evodiamine in its binding to protein hosts: a comparative spectroscopic and molecular modeling evaluation with rutaecarpine

“…For this purpose, chenodeoxycholic acid was selected which inhibits the binding the subdomain IIA marker warfarin to HSA. 31 Its addition reduced the amplitude of the ICD band of EVD by about 60% and also rendered the UV band of the alkaloid similar to that measured in buffer solution (Suppl. Fig.…”

Effect of drugs on cholesterol crystallization in an artificial bile model and relation of this effect to drug binding to albumin

“…This site has been identified as a possible primary binding site of both bile salts [4,9,10] and Ca 2+ ion [8]. This site has been identified as a possible primary binding site of both bile salts [4,9,10] and Ca 2+ ion [8].…”

“…The affinity of some drugs for binding Site-I on the albumin molecule was probably the cause of this effect. This site has been identified as a possible primary binding site of both bile salts [4,9,10] and Ca 2+ ion [8]. In addition, the TDC-HSA-Ca 2+ complex has been found to be a more potent accelerator of cholesterol crystallization than the TDC-HSA complex.…”

“…Studies by Sudlow et al [6] led to the classification of drug binding sites on HSA molecule into two categories, which were denoted Site-I and Site-II. Among many other substances ethanol [7], Ca 2+ ions [8] and possibly bile salts [4,9,10] were found to bind to Site-I.…”

Síntesis de Derivados Fotoactivos de Ácidos Biliares para Aplicaciones Biológicas

“…Aun así, los resultados son contradictorios en muchos casos y el sitio de unión no se ha establecido definitivamente. Por ejemplo, en experimentos por cromatografía de gel o diálisis de equilibro se concluyó que el sitio de unión coincidía con el de oleato, warfarina o dansilsarcosina (sitio 1); [130][131][132] por otra parte, experimentos de calorimetría demostraron que los BAs se unen al sitio 2.…”