title: Reviewing the binding of a series of parabens to human serum albumin.
abstract: To better understand the factors that contribute to the accumulation of unmetabolized parabens (p-hydroxybenzoic acid esters) in breast cancer tissue, the binding of a series of parabens (methyl-, ethyl-, butyl-, benzyl-paraben) to human serum albumin (HSA) was investigated by fluorescence spectroscopy and also their ability to modify the binding parameters of albumin site markers. Emission spectra of HSA upon fluorescence excitation of Trp 214 residue at 295 nm were recorded at different molar ratios of PB/HSA and data were corrected for the inner-filter effect. A significant inner-filter effect was obtained for molar ratios of 2.0 and above. For lower molar ratios, a slight increase in fluorescence of HSA was detected. p-Hydroxybenzoic acid, the main metabolite of parabens, did not modify the fluorescence of HSA whatever the molar ratio used. Binding parameters for compounds that are markers of site I, bilirubin and warfarin, were determined in the absence and presence of methyl, butyl and benzyl paraben at molar ratios of PB/HSA of 0, 1 and 2. No variation of the binding constants of these markers was observed. The results indicate that parabens weakly interact with HSA thus suggesting that they are in a free form in blood and therefore more available to reach tissues.
authors: Bioactive Molecules Research Group, Doctoral School of Science and Technology, Research Platform for Environmental Science, Lebanese University, Lebanon. hgreige@ul.edu.lb
authors: Hélène
authors: H
authors: Greige-Gerges
authors: Rana
authors: R
authors: Kaissi
authors: Jacques
authors: J
authors: Magdalou
authors: Alia
authors: A
authors: Jraij
mesh_terms: D001663:Bilirubin / Q000378:metabolism; D001665:Binding Sites; D006801:Humans; D010226:Parabens / Q000378:metabolism*; D011485:Protein Binding; D012709:Serum Albumin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014859:Warfarin / Q000378:metabolism
chemical_list: D010226:Parabens; D012709:Serum Albumin; D014859:Warfarin; D001663:Bilirubin