Abstract:
Oxygen is essential for aerobic life on earth but it is also the origin of harmful reactive oxygen species (ROS). Ubiquinone is par excellence the endogenous cellular antioxidant, but a very hydrophobic one. Because of that, other molecules have been envisaged, such as idebenone (IDE) and mitoquinone (MTQ), molecules having the same redox active benzoquinone moiety but higher solubility. We have used molecular dynamics to determine the location and interaction of these molecules, both in their oxidized and reduced forms, with membrane lipids in a membrane similar to that of the mitochondria. Both IDE and reduced IDE (IDOL) are situated near the membrane interface, whereas both MTQ and reduced MTQ (MTQOL) locate in a position adjacent to the phospholipid hydrocarbon chains. The quinone moieties of both ubiquinone 10 (UQ10) and reduced UQ10 (UQOL10) in contraposition to the same moieties of IDE, IDOL, MTQ and MTQOL, located near the membrane interphase, whereas the isoprenoid chains remained at the middle of the hydrocarbon chains. These molecules do not aggregate and their functional quinone moieties are located in the membrane at different depths but near the hydrophobic phospholipid chains whereby protecting them from ROS harmful effects.
摘要:
氧气对于地球上的有氧生命至关重要,但它也是有害活性氧(ROS)的起源。泛醌是卓越的内源性细胞抗氧化剂,但是非常疏水。正因为如此,已经设想了其他分子,如艾地苯醌(IDE)和米托醌(MTQ),具有相同氧化还原活性苯醌部分但溶解度较高的分子。我们已经使用分子动力学来确定这些分子的位置和相互作用,以氧化和还原的形式,膜脂质类似于线粒体的膜。IDE和还原IDE(IDOL)都位于膜界面附近,而MTQ和还原MTQ(MTQOL)都位于磷脂烃链附近的位置。泛醌10(UQ10)和还原UQ10(UQOL10)的醌部分与IDE的相同部分相反,偶像,MTQ和MTQOL,位于膜界面附近,而类异戊二烯链保持在烃链的中间。这些分子不聚集,并且它们的官能醌部分位于膜中的不同深度,但靠近疏水性磷脂链,从而保护它们免受ROS有害作用。