title: Cucurbitacins from Ecballium elaterium juice increase the binding of bilirubin and ibuprofen to albumin in human plasma.
abstract: Ecballium elaterium, a medicinal plant, whose fruit juice is used for the treatment of jaundice in folk medicine, has been reported as being capable of decreasing bilirubinemia in animals with jaundice [H.H. Elayan, M.N. Garaibeh, S.M. Zmeili, S.A. Salhab, Effects of Ecballium elaterium juice on serum bilirubin concentration in male rats, Int. J. Crude Drug Res. 27 (1989) 227-234]. The aim of this study is to identify the Ecballium elaterium components, which are able to modify the binding of bilirubin to albumin. The juice is fiber-free but contains proteins, lipids, sugars, and minerals. The extract of the juice, analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), contains cucurbitacins (Cuc) B, D, E, and I as well as several glycosylated compounds. Human plasma containing no or serial concentrations of Ecballium elaterium components were prepared and the direct bilirubin (DB) and total bilirubin (TB) were determined by the Jendrassik and Grof method. Our results showed that Cuc D, E, and B decreased the levels of DB and TB in plasma, while Cuc I, glycosyl derivatives, and proteins of the juice did not modify the bilirubin levels. The binding of domain specific ligands to HSA, bilirubin (domain IIA), and ibuprofen (domain IIIA), were studied in the absence and presence of Cuc D, E, and I, by fluorescence spectroscopy. The values of binding constant K(a) and binding site number n, determined by Scatchard method, increased for the both ligands only in the presence of Cuc E and D. Cuc I decreased slightly the K(a) of ibuprofen, suggesting an interaction with the domain IIIA of the protein. As a conclusion, Cuc E, D, and B produce rearrangement in the structure of albumin leading to increase the binding of domain specific ligands, ibuprofen and bilirubin.
authors.affiliation: Université Saint-Esprit de Kaslik, Faculté des Sciences et de Génie Informatique, B.P. 446 Jounieh, Lebanon. helenegreige@usek.edu.lb
authors.forename: Hélène
authors.initials: H
authors.lastname: Greige-Gerges
authors.forename: Rony Abou
authors.initials: RA
authors.lastname: Khalil
authors.forename: Eliane Abou
authors.initials: EA
authors.lastname: Mansour
authors.forename: Jacques
authors.initials: J
authors.lastname: Magdalou
authors.forename: Ramez
authors.initials: R
authors.lastname: Chahine
authors.forename: Naïm
authors.initials: N
authors.lastname: Ouaini
mesh_terms: D001663:Bilirubin / Q000097:blood / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D019662:Cucurbitaceae / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007052:Ibuprofen / Q000097:blood / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D012709:Serum Albumin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D017186:Titrimetry; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D012709:Serum Albumin; D014315:Triterpenes; D001663:Bilirubin; D007052:Ibuprofen