Profiling of Free Fatty Acids Using Stable Isotope Tagging Uncovers a Role for Saturated Fatty Acids in Neuroexocytosis. Issue 11 (19th November 2015)

• Record Type: Journal Article
• Authors: Narayana, Vinod K.; Tomatis, Vanesa M.; Wang, Tong; Kvaskoff, David; Meunier, Frederic A.
• Is Part Of: Chemistry & biology. Volume 22:Issue 11(2015)
• Page Start: 1552
• Page End: 1561
• Publication Date: 2015-11-19
• Subjects: Biochemistry -- Periodicals; 540
• DOI: 10.1016/j.chembiol.2015.09.010
• Languages: English
• ISSNs: 1074-5521

Abstract

Summary: The phospholipase-catalyzed release of free fatty acids (FFAs) from phospholipids is implicated in many critical biological processes such as neurotransmission, inflammation, and cancer. However, determining the individual change in FFAs generated during these processes has remained challenging due to the limitations of current methods, and has hampered our understanding of these key mediators. Here, we developed an "iTRAQ"-like method for profiling FFAs by stable isotope tagging (FFAST), based on the differential labeling of the carboxyl group and designed to resolve analytical variance, through a multiplexed assay in cells and subcellular fractions. With nanomolar sensitivity, this method revealed a spectrum of saturated FFAs elicited during stimulation of exocytosis that was identical in neurons and neurosecretory cells. Purified secretory vesicles also generated these FFAs when challenged with cytosol. Our multiplex method will be invaluable to assess the range of FFAs generated in other physiological and pathological settings. Graphical Abstract: Highlights: FFAST method enables multiplexed fatty acid profiling with nanomolar sensitivity Main free fatty acids (FFAs) generated during neuroexocytosis are saturated Generation of saturated FFAs suggests an unexpected role of PLA1 FFAs generated in secretory vesicles highlights a key role for Ca 2+ and cytosol Abstract : Narayana et al. developed a free fatty acid stable isotope tagging (FFAST) method that enables multiplexed quantification of endogenous free fatty acids with nanomolar sensitivity. Here, they uncover an unexpected variety of change in free fatty acids generated during neuroexocytosis in neurons and chromaffin cells.