Unsaturated long-chain fatty acids inhibit the binding of oxidized low-density lipoproteins to a model CD36

• Published in: Bioscience, biotechnology, and biochemistry biotechnology, and biochemistry, 2014-02, Vol.78 (2), p.238-244
• Main Authors: Takai, Marie, Kozai, Yuki, Tsuzuki, Satoshi, Matsuno, Yukari, Fujioka, Maiko, Kamei, Kozue, Inagaki, Hitomi, Eguchi, Ai, Matsumura, Shigenobu, Inoue, Kazuo, Fushiki, Tohru
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; binding inhibition; CD36; CD36 Antigens - chemistry; CD36 Antigens - metabolism; Fatty Acids, Unsaturated - chemistry; Fatty Acids, Unsaturated - pharmacology; Glycerophospholipids - metabolism; HEK293 Cells; Humans; Lipoproteins, LDL - metabolism; long-chain fatty acids; Molecular Sequence Data; oxidized low-density lipoproteins; Peptide Fragments - chemistry; Peptide Fragments - metabolism; Protein Binding; synthetic peptide
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1080/09168451.2014.882750

Transmembrane protein CD36 binds multiple ligands, including oxidized low-density lipoproteins (oxLDLs) and long-chain fatty acids (LCFAs). Our aim was to determine whether LCFAs compete with oxLDLs for binding to CD36. We addressed this issue by examining the inhibitory effect of LCFAs against the binding of Alexa-fluor-labeled oxLDLs (AFL-oxLDL) to a synthetic peptide representing the oxLDL-binding site on CD36 (3S-CD36 150-168 ). All of the unsaturated LCFAs tested, inhibited the binding of AFL-oxLDL to 3S-CD36 150-168 , albeit to varying degrees. For instance, the concentrations required for 50% inhibition of binding for oleic, linoleic, and α-linolenic acids were 0.25, 0.97, and 1.2 mM, respectively. None of the saturated LCFAs tested (e.g. stearic acid) exhibited inhibitory effects. These results suggest that at least unsaturated LCFAs can compete with oxLDLs for binding to CD36. The study also provides information on the structural requirements of LCFAs for inhibition of oxLDLs-CD36 binding. Unsaturated long-chain fatty acids but not saturated ones compete with Alexa-Fluor-labeled oxidized low-density lipoproteins for binding to a synthetic CD36 peptide.