Comparison of MRS with Fluorescence for Molecular Imaging and Determination of Phospholipase Isoforms

Daniel-Joseph Leung¹, Theresa Mawn¹, Edward James Delikatny¹

We present the modulation of MR-visible metabolic response through the inhibition of the calcium-independent phospholipase A2 (iPLA2) and the cytosolic phospholipase A2 (cPLA2) isoforms and their differential roles in mediating lipid responses using the specific inhibitors BEL and AACOCF3, respectively. At the same time, a separate pathway of overall phospholipase A2 (sPLA2 isoform) activity is shown by kinetic fluorescence activation in vitro. This not only suggests the possibility of using MRS and optical methods to compare findings, but also the ability to characterize enzyme isoforms relevant to tumor drug response collaterally.