title: Diosmin binding to human serum albumin and its preventive action against degradation due to oxidative injuries.
abstract: Diosmin is a glycosylated polyphenolic compound, commonly found in fruits and vegetables, which is utilized for the pharmacological formulation of some drugs. The interactions of diosmin to human serum albumin have been investigated by fluorescence, UV-visible, FTIR spectroscopy, native electrophoresis and protein-ligand docking studies. The fluorescence studies indicate that the binding site of the additive involves modifications of environment around Trp214 at the level of subdomain IIA. Combining the curve-fitting results of infrared Amide I' band, the modifications of protein secondary structure have been estimated, indicating a decrease in α-helix structure following flavonoid binding. Data obtained by fluorescence and UV-visible spectroscopy, FTIR experiments and molecular modeling afforded a clear picture of the association mode of diosmin to HSA, suggesting that the primary binding site of diosmin is located in Sudlow's site I. Computational mapping confirms this observation suggesting that the possible binding site of diosmin is located in the hydrophobic cavity of subdomain IIA, whose microenvironment is able to help and stabilize the binding of the ligand in non-planar conformation. Moreover the binding of diosmin to HSA significantly contributes to protect the protein against degradation due to HCLO and Fenton reaction.
authors.affiliation: Dipartimento di Scienze Chimiche, Università di Messina, Viale F. Stagno d'Alcontres 31, 98166 Messina, Italy. Electronic address: dbarreca@unime.it.
authors.forename: Davide
authors.initials: D
authors.lastname: Barreca
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Laganà
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bruno
authors.forename: Salvatore
authors.initials: S
authors.lastname: Magazù
authors.forename: Ersilia
authors.initials: E
authors.lastname: Bellocco
mesh_terms: D001665:Binding Sites; D004145:Diosmin / Q000737:chemistry / Q000378:metabolism*; D004586:Electrophoresis; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D018384:Oxidative Stress; D011487:Protein Conformation; D059748:Proteolysis; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D008024:Ligands; D012709:Serum Albumin; D004145:Diosmin
keywords: Diosmin; FTIR; Fluorescence; Human serum albumin; Protein degradation