title: An in vitro study on the antioxidant capacity of usnic acid on human erythrocytes and molecular models of its membrane.
abstract: Usnic acid (UA) has been associated with chronic diseases through its antioxidant action. Its main target is the cell membrane; however, its effect on that of human erythrocytes has been scarcely investigated. To gain insight into the molecular mechanisms of the interaction between UA and cell membranes human erythrocytes and molecular models of its membrane have been utilized. Dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were chosen as representative of phospholipid classes located in the outer and inner monolayers of the erythrocyte membrane, respectively. Results by X-ray diffraction showed that UA produced structural perturbations on DMPC and DMPE bilayers. DSC studies have indicated that thermotropic behavior of DMPE was most strongly distorted by UA than DMPC, whereas the latter is mainly affected on the pretransition. Scanning electron (SEM) and defocusing microscopy (DM) showed that UA induced alterations to erythrocytes from the normal discoid shape to echinocytes. These results imply that UA molecules were located in the outer monolayer of the erythrocyte membrane. Results of its antioxidant properties showed that UA neutralized the oxidative capacity of HClO on DMPC and DMPE bilayers; SEM, DM and hemolysis assays demonstrated the protective effect of UA against the deleterious oxidant effects of HClO upon human erythrocytes.
authors: Faculty of Chemical Sciences, University of Concepción, Concepción, Chile. Electronic address: msuwalsk@udec.cl.
authors: M
authors: M
authors: Suwalsky
authors: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland; Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
authors: M
authors: M
authors: Jemiola-Rzeminska
authors: Faculty of Chemical Sciences, University of Concepción, Concepción, Chile.
authors: C
authors: C
authors: Astudillo
authors: Center for Optics and Photonics, University of Concepción, Concepción, Chile.
authors: M J
authors: MJ
authors: Gallardo
authors: Center for Optics and Photonics, University of Concepción, Concepción, Chile.
authors: J P
authors: JP
authors: Staforelli
authors: Faculty of Biological Sciences, University of Concepción, Concepción, Chile.
authors: F
authors: F
authors: Villena
authors: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland; Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
authors: K
authors: K
authors: Strzalka
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001572:Benzofurans / Q000737:chemistry / Q000494:pharmacology*; D048430:Cell Shape / Q000187:drug effects; D002478:Cells, Cultured; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004910:Erythrocyte Membrane / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D006997:Hypochlorous Acid / Q000494:pharmacology; D008051:Lipid Bilayers / Q000737:chemistry; D008853:Microscopy / Q000379:methods; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D015394:Molecular Structure; D010714:Phosphatidylethanolamines / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000975:Antioxidants; D001572:Benzofurans; D008051:Lipid Bilayers; D010714:Phosphatidylethanolamines; C073339:usnic acid; D006997:Hypochlorous Acid; D004134:Dimyristoylphosphatidylcholine; C018525:1,2-dimyristoylphosphatidylethanolamine
keywords: Antioxidant; Erythrocyte membrane; Phospholipid bilayer; Usnic acid