MetaTOC stay on top of your field, easily

The Loss Of Macrophage Fatty Acid Oxidation Does Not Potentiate Systemic Metabolic Dysfunction

, , , , , ,

AJP Endocrinology and Metabolism

Published online on

Abstract

Fatty acid oxidation in macrophages has been suggested to play a causative role in high-fat diet-induced metabolic dysfunction, particularly in the etiology of adipose driven insulin resistance. To understand the contribution of macrophage fatty acid oxidation directly to metabolic dysfunction in high-fat diet-induced obesity, we generated mice with a myeloid-specific knockout of carnitine palmitoyltransferase 2 (CPT2 M-KO), an obligate step in mitochondrial long-chain fatty acid oxidation. While fatty acid oxidation was clearly induced upon IL-4 stimulation, fatty acid oxidation deficient CPT2 M-KO bone marrow derived macrophages (BMDM) displayed canonical markers of M2 polarization following IL-4 stimulation in vitro. In addition, loss of macrophage fatty acid oxidation in vivo did not alter the progression of high-fat diet induced obesity, inflammation, macrophage polarization, oxidative stress, or glucose intolerance. These data suggest that although alternatively activated macrophages up-regulate fatty acid oxidation, fatty acid oxidation is dispensable for macrophage polarization and high-fat diet-induced metabolic dysfunction. Macrophage fatty acid oxidation likely plays a correlative rather than causative role in systemic metabolic dysfunction.