Karbanova 2015 Abstract MiP2015
|CD36 does not directly participate in mitochondrial fatty acid transport and oxidation.
D36/FAT permease of plasma membrane is the key transmembrane transport protein for long chain fatty acids (FA). In the last years, conflicting results have been published regarding the localization of CD36 in mitochondria and its direct role in mitochondrial FA transport and oxidation.
We used the spontaneously hypertensive rat (SHR) that harbors mutant CD36 and transgenic SHR expressing wild type Cd36 (SHR-Cd36) and compered parameters of lipid metabolism in brown adipose tissue (BAT).
CD36 protein in BAT was high, comparable to heart and present mostly in a glycosylated form. Of all tissues the Cd36 transcript was the highest in BAT (2.9 x higher than heart). Most of the CD36 signal was in microsomal fraction and only traces in mitochondria, most likely due to contamination. We also compared palmitate transport and oxidation in BAT and in primary cultures of brown adipocytes from SHR and SHR-Cd36 to test whether palmitate transport and oxidation is affected by mutant CD36. The import of palmitate into BAT was reduced in the SHR when compared to SHR-Cd36 rats (24.1±0.8 vs. 29.0±1.6 nmol palm/mg prot/2h, P<0.05), confirming that FA transport across plasma membrane mediated by mutant CD36 is less effective. In contrast, there was no significant difference in palmitate oxidation in BAT from SHR and SHR-Cd36 rats (2.1±0.1 vs. 2.1±0.1 nmol palm/mg prot/2h), suggesting that CD36 is not important for FA transport into mitochondria.
Our results demonstrate the important role of CD36 in transport of long chain FA across plasma membrane but not into mitochondria. We were not able to detect a significant amount of CD36 in isolated mitochondria and CD36 does not seem to directly participate in mitochondrial FA transport and oxidation.
Labels: MiParea: mt-Membrane, nDNA;cell genetics, Comparative MiP;environmental MiP
Organism: Rat Tissue;cell: Fat Preparation: Isolated mitochondria
Event: E1, Poster MiP2015
1-Inst Physiology Czech Acad Sc; 2-Center Experimental Med, Inst Clinical Experimental Med, Prague, Czech Republic. - [email protected]
Research relating to this abstract was funded by ERC CZ LL1204 and Grant Agency of the Czech Republic (14-36804G).