Related Experiment Video
Updated: May 3, 2026
Fluorescence-quenching of a Liposomal-encapsulated Near-infrared Fluorophore as a Tool for In Vivo Optical Imaging
Published on: January 5, 2015
Unexpected omega-3 activities in intracellular lipolysis and macrophage foaming revealed by fluorescence lifetime
Hesen Tang1, Zhengjie Liu1, Guangmei Han1
1Institute of Physical Science and Information Technology, School of Chemistry and Chemical Engineering, Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China.
Abstract:
Omega-3 polyunsaturated fatty acids (PUFA) found primarily in fish oil have been a popular supplement for cardiovascular health because they can substantially reduce circulating triglyceride levels in the bloodstream to prevent atherosclerosis. Beyond this established extracellular activity, here, we report a mode of action of PUFA, regulating intracellular triglyceride metabolism and lipid droplet (LD) dynamics. Real-time imaging of the subtle and highly dynamic changes of intracellular lipid metabolism was enabled by a fluorescence lifetime probe that addressed the limitations of intensity-based fluorescence quantifications. Surprisingly, we found that among omega-3 PUFA, only docosahexaenoic acid (DHA) promoted the lipolysis in LDs and reduced the overall fat content by approximately 50%, and consequently helped suppress macrophage differentiation into foam cells, one of the early steps responsible for atherosclerosis. Eicosapentaenoic acid, another omega-3 FA in fish oil, however, counteracted the beneficial effects of DHA on lipolysis promotion and cell foaming prevention. These in vitro findings warrant future validation in vivo.
