Jean Chung - Colorado State University
The accumulation of lipid peroxides on cellular membranes is a process that accompanies aging as well as a host of age-related diseases, such as cancer, Alzheimer’s disease, stroke, and heart diseases. Despite their fundamental role in aging and health, the mechanistic nature of lipid oxidation and its connection to the diseased state in cells remain elusive. This may be because lipid oxidation studies are usually carried out in live cell context, where quantitative measurements are difficult, or with lipids in organic solvents, where it lacks biological relevance. There are two important questions with respect to lipid oxidation: one is which of the two fundamentally different pathways, enzymatic peroxidation or non-enzymatic autoxidation involving free iron, is responsible for the membrane lipid oxidation in cells. The other is how lipid oxidation leads to adverse cellular outcomes. To investigate these problems, we have developed a membrane-based assay for quantitative measurement of lipid oxidation. By using fluorescence spectroscopy to detect the generation of lipid oxides, we elucidate chemical mechanism of lipid oxidation in the membrane context.