SSO and other putative inhibitors of FA transport across membranes by CD36 disrupt intracellular metabolism, but do not affect FA translocation

• DOI: 10.1194/jlr.ra120000648
• Publication Date: 2020-02-27T04:45:14Z
• Authors: Anthony G. Jay; Jeffrey R. Simard; Nasi Huang; James A. Hamilton
• Keywords: CD36; Affect

Membrane-bound proteins have been proposed to mediate the transport of long-chain FA (LCFA) through plasma membrane (PM). These proposals are based largely on reports that PM LCFAs can be blocked by a number enzymes and purported inhibitors LCFA transport. Here, using ratiometric pH indicator (2',7'-bis-(2-carboxyethyl)-5-(and-6-)-carboxyfluorescein acrylodated intestinal FA-binding protein-based dual fluorescence assays, we investigated effects nine putative transporter protein CD36 binding transmembrane movement LCFAs. We particularly focused sulfosuccinimidyl oleate (SSO), reported competitive inhibitor CD36-mediated Using these assays in adipocytes inhibitor-treated protein-free lipid vesicles, demonstrate rapid across model biological membranes remains unchanged presence inhibitors. previously shown live cells does not accelerate unesterified PM. Our present experiments indicated disruption metabolism inside cell within minutes upon treatment with many "inhibitors" assumed inhibit Furthermore, confocal microscopy specific anti-SSO antibody, found numerous intracellular PM-bound SSO-modified addition CD36. results support hypothesis diffuse rapidly do require an active for their movement.