The role of protein-mediated transport in regulating mitochondrial long-chain fatty acid oxidation

摘要

This thesis is an investigation of the role of fatty acid translocase (FAT/CD36), plasma membrane associatednfatty acid binding protein (FABPpm), and carnitine palmitoyltransferase I (CPTI) in transporting long-chain fatty acidsn(LCFAs) across mitochondrial membranes. Maximal CPTI activity, as well as the sensitivity of CPTI for its substrate palmitoyl-nCoA (P-CoA) and its inhibitor malonyl-CoA (M-CoA), were measured in mitochondria isolated from human vastusnlateralis muscles at rest and following muscle contraction. Exercise did not alter maximal CPTI activity or the sensitivitynof CPTI for P-CoA. In contrast, exercise progressively attenuated the ability of M-CoA to inhibit CPTI activity. MitochondrialnFAT/CD36 protein content was also measured at rest, during, and following 2 h of cycling at ~60% maximal oxygennuptake. Exercise progressively increased the content of mitochondrial FAT/CD36 (+59%), which was significantly (p