Dr. Sun is an expert on "hunger hormone" ghrelin. She generated the first set of ghrelin and ghrelin receptor knockout mice, and discovered novel roles of ghrelin signaling in diabetes, thermogenesis, and inflammation. Her laboratory uses state-of-the-art tools to study ghrelin system in energy sensing, metabolism and immunity, and aging. Her work suggests that ghrelin signal might be a promising drug target for obesity, diabetes, inflammation, and Alzheimer's disease.