KCS

Oxidative stress occurs when production of reactive oxygen species (ROS), which include oxygen derived radical species such as superoxide anion (O2∙-) and hydroxyl radical(∙OH) as well as hydrogen peroxide (H2O2), exceeds removal capacity of antioxidants. Moderate concentration of ROS is related to some beneficial physiological roles (e.g. signaling, host defense), but high levels of ROS not only induces cellular impairments by altering DNA, RNA, proteins, and lipids but also involves with a number of diseases like cardiovascular disease (CVD) or cancer. Exosomes are nano-sized extracellular vesicles secreted from cells. It has been reported that exosome transports some protective RNA against oxidative stress or transfers stress signals to recipient cells, when oxidative stress is given to cells. However, physiological roles or changes of lipids in exosome during oxidative stress conditions have not yet been studied. In this study, oxidative stress was induced to human embryonic kidney cell 293 (HEK293) by treating with H2O2 for 72 hours. Exosome and cellular organelles from control and oxidatively stressed conditions were size-sorted by flow field-flow fractionation first. Then, changes in lipid profiles in cell and exosome was conducted by nUHPLC-ESI-MS/MS.