Abstract

Oxidative stress plays an essential role in the regulation of vital processes in living organisms. Reactive oxygen species can react chemically with the constituents of the cells leading to irreversible damage. The first structure of the cell in contact with the environment that surrounds it is the membrane, which protects it and allows the exchange of substances. Some signals manifest when the components of a bilayer are undergoing oxidation, like an increase in the lipid area, decrease in the thickness of the bilayer, and exchange of the oxidized groups toward the bilayer surface. In this investigation, a molecular dynamics simulation was done on a set of Dioleoylphosphatidylcholine membranes with different percentage of oxidized lipids, in order to observe the effect of the oxidation degree on the membrane structure. It was found that, as higher the concentration of oxidized lipids is, the larger the damage of the membrane. This is reflected in the increase in the lipid area and the decrease in the thickness and membrane packing. Also, it was observed that hydrophobicity inside the membrane decreases as the oxidation percentage increases.

Communicated by Ramaswamy H. Sarma

摘要

氧化应激在生物体生命过程的调节中起着至关重要的作用。活性氧可以与细胞成分发生化学反应，导致不可逆转的损伤。细胞与周围环境接触的第一个结构是膜，它保护它并允许物质交换。当双层的成分发生氧化时，一些信号会表现出来，例如脂质面积增加、双层厚度减少以及氧化基团向双层表面交换。在这项研究中，对一组具有不同氧化脂质百分比的二油酰磷脂酰胆碱膜进行了分子动力学模拟，以观察氧化程度对膜结构的影响。结果发现，氧化脂质浓度越高，膜的损伤越大。这反映在脂质面积的增加以及厚度和膜堆积的减少上。此外，观察到膜内的疏水性随着氧化百分比的增加而降低。

由 Ramaswamy H. Sarma 传达