Scavenger receptor class B, type 1 facilitates cellular fatty acid uptake

W Wang, Z Yan, J Hu, WJ Shen, S Azhar… - Biochimica et Biophysica …, 2020 - Elsevier
W Wang, Z Yan, J Hu, WJ Shen, S Azhar, FB Kraemer
Biochimica et Biophysica Acta (BBA)-Molecular and Cell Biology of Lipids, 2020Elsevier
SR-B1 belongs to the class B scavenger receptor, or CD36 super family. SR-B1 and CD36
share an affinity for a wide array of ligands. Although they exhibit similar ligand binding
specificity, SR-B1 and CD36 have some very specific lipid transport functions. Whereas SR-
B1 primarily facilitates the selective delivery of cholesteryl esters (CEs) and cholesterol from
HDL particles to the liver and non-placental steroidogenic tissues, as well as participating in
cholesterol efflux from cells, CD36 primarily mediates the uptake of long-chain fatty acids in …
Abstract
SR-B1 belongs to the class B scavenger receptor, or CD36 super family. SR-B1 and CD36 share an affinity for a wide array of ligands. Although they exhibit similar ligand binding specificity, SR-B1 and CD36 have some very specific lipid transport functions. Whereas SR-B1 primarily facilitates the selective delivery of cholesteryl esters (CEs) and cholesterol from HDL particles to the liver and non-placental steroidogenic tissues, as well as participating in cholesterol efflux from cells, CD36 primarily mediates the uptake of long-chain fatty acids in high fatty acid-requiring organs such as the heart, skeletal muscle and adipose tissue. However, CD36 also mediates cholesterol efflux and facilitates selective lipoprotein-CE delivery, although less efficiently than SR-B1. Interestingly, the ability or efficiency of SR-B1 to mediate fatty acid uptake has not been reported. In this paper, using overexpression and siRNA-mediated knockdown of SR-B1, we show that SR-B1 possesses the ability to facilitate fatty acid uptake. Moreover, this function is not blocked by BLT-1, a specific chemical inhibitor of HDL-CE uptake activity of SR-B1, nor by sulfo-N-succinimidyl oleate, which inhibits fatty acid uptake by CD36. Attenuated fatty acid uptake was also observed in primary adipocytes isolated from SR-B1 knockout mice. In conclusion, facilitation of fatty acid uptake is an additional function that is mediated by SR-B1.
Elsevier