Your browser doesn't support javascript.
loading
Is the cholesterol bilayer domain a barrier to oxygen transport into the eye lens?
Plesnar, Elzbieta; Szczelina, Robert; Subczynski, Witold K; Pasenkiewicz-Gierula, Marta.
Afiliación
  • Plesnar E; Department of Computational Biophysics and Bioinformatics, WBBiB, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland. Electronic address: elzbieta.pieniazek@uj.edu.pl.
  • Szczelina R; Department of Bioinformatics, MCB, Jagiellonian University, Gronostajowa 7A, 30-387 Krakow, Poland. Electronic address: robert.szczelina@uj.edu.pl.
  • Subczynski WK; Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA. Electronic address: subczyn@mcw.edu.
  • Pasenkiewicz-Gierula M; Department of Computational Biophysics and Bioinformatics, WBBiB, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland. Electronic address: marta.pasenkiewicz-gierula@uj.edu.pl.
Biochim Biophys Acta Biomembr ; 1860(2): 434-441, 2018 Feb.
Article en En | MEDLINE | ID: mdl-29079282
In the eye lens, the oxygen partial pressure is very low and the cholesterol (Chol) content in cell membranes is very high. Disturbance of these quantities results in cataract development. In human lens membranes, both bulk phospholipid-Chol domains and the pure Chol bilayer domains (CBDs) were experimentally detected. It is hypothesized that the CBD constitutes a significant barrier to oxygen transport into the lens. Transmembrane profiles of the oxygen diffusion-concentration product, obtained with electron paramagnetic resonance spin-labeling methods, allow evaluation of the oxygen permeability (PM) of phospholipid membranes but not the CBD. Molecular dynamics simulation can independently provide components of the product across any bilayer domain, thus allowing evaluation of the PM across the CBD. Therefore, to test the hypothesis, MD simulation was used. Three bilayers containing palmitoyl-oleoyl-phosphorylcholine (POPC) and Chol were built. The pure Chol bilayer modeled the CBD, the 1:1 POPC-Chol bilayer modeled the bulk membrane in which the CBD is embedded, and the POPC bilayer was a reference. To each model, 200 oxygen molecules were added. After equilibration, the oxygen concentration and diffusion profiles were calculated for each model and multiplied by each other. From the respective product profiles, the PM of each bilayer was calculated. Favorable comparison with experimental data available only for the POPC and POPC-Chol bilayers validated these bilayer models and allowed the conclusion that oxygen permeation across the CBD is ~10 smaller than across the bulk membrane, supporting the hypothesis that the CBD is a barrier to oxygen transport into the eye lens.
Asunto(s)
Palabras clave
Texto completo
Añadir a Mi BVS
Imprimir
XML
PubMed Links
Buscar en Google

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Asunto principal: Oxígeno / Colesterol / Cristalino / Membrana Dobles de Lípidos Límite: Humans Idioma: En Revista: Biochim Biophys Acta Biomembr Año: 2018 Tipo del documento: Article Pais de publicación: Países Bajos
Texto completo
Añadir a Mi BVS
Imprimir
XML
PubMed Links
Buscar en Google

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Asunto principal: Oxígeno / Colesterol / Cristalino / Membrana Dobles de Lípidos Límite: Humans Idioma: En Revista: Biochim Biophys Acta Biomembr Año: 2018 Tipo del documento: Article Pais de publicación: Países Bajos