Saturated very long-chain fatty acids regulate macrophage plasticity and invasiveness.

Abstract

Saturated very long-chain fatty acids (VLCFA, ≥ C22), enriched in brain myelin and innate immune cells, accumulate in X-linked adrenoleukodystrophy (X-ALD) due to inherited dysfunction of the peroxisomal VLCFA transporter ABCD1. In its severest form, X-ALD causes cerebral myelin destruction with infiltration of pro-inflammatory skewed monocytes/macrophages. How VLCFA levels relate to macrophage activation is unclear. Here, whole transcriptome sequencing of X-ALD macrophages indicated that VLCFAs prime human macrophage membranes for inflammation and increased expression of factors involved in chemotaxis and invasion. When added externally to mimic lipid release in demyelinating X-ALD lesions, VLCFAs did not activate toll-like receptors in primary macrophages. In contrast, VLCFAs provoked pro-inflammatory responses through scavenger receptor CD36-mediated uptake, cumulating in JNK signalling and expression of matrix-degrading enzymes and chemokine release. Following pro-inflammatory LPS activation, VLCFA levels increased also in healthy macrophages. With the onset of the resolution, VLCFAs were rapidly cleared in control macrophages by increased peroxisomal VLCFA degradation through liver-X-receptor mediated upregulation of ABCD1. ABCD1 deficiency impaired VLCFA homeostasis and prolonged pro-inflammatory gene expression upon LPS treatment. Our study uncovers a pivotal role for ABCD1, a protein linked to neuroinflammation, and associated peroxisomal VLCFA degradation in regulating macrophage plasticity.

• Authors: Bettina Zierfuss, Agnieszka Buda, Andrea Villoria-González, Maxime Logist, Jure Fabjan, Patricia Parzer, Claire Battin, Streggi Vandersteene, Inge M E Dijkstra, Petra Waidhofer-Söllner, Katharina Grabmeier-Pfistershammer, Peter Steinberger, Stephan Kemp, Sonja Forss-Petter, Johannes Berger, Isabelle Weinhofer
• Journal: Journal of neuroinflammation (J Neuroinflammation) Vol. 19 Issue 1 Pg. 305 (Dec 17 2022) ISSN: 1742-2094 [Electronic] England
• PMID: 36528616 (Publication Type: Journal Article)
• Copyright: © 2022. The Author(s).

Chemical References

• Lipopolysaccharides
• ATP-Binding Cassette Transporters
• Fatty Acids

Topics

• Humans
• Adrenoleukodystrophy (genetics, metabolism)
• Lipopolysaccharides
• ATP-Binding Cassette Transporters (genetics, metabolism)
• Fatty Acids (metabolism)
• Macrophages (metabolism)