Very long chain fatty acid β-oxidation in astrocytes: contribution of the ABCD1-dependent and -independent pathways

Biol Pharm Bull. 2012;35(11):1972-9. doi: 10.1248/bpb.b12-00411.

Abstract

Very long chain fatty acid (VLCFA) metabolism in astrocytes is important for the maintenance of myelin structure in central nervous system. To analyze the contribution of the ABCD1-dependent and -independent pathways to VLCFA metabolism in astrocytes, we prepared human glioblastoma U87 cells with a silencing of ABCD1 and primary astrocytes from abcd1-deficient mice, and measured fatty acid β-oxidation in the presence or absence of a potent inhibitor of carnitine palmitoyltransferase I, 2-[5-(4-chlorophenyl)pentyl]oxirane-2-carboxylate (POCA). In U87 cells, C24:0 β-oxidation was decreased to ca. 70% of the control in the presence of POCA, and the activity was further decreased to ca. 20% by the silencing of ABCD1. In mouse primary astrocytes, C24:0 β-oxidation was also decreased to ca. 70% of the control in the presence of POCA. The C24:0 β-oxidation in Abcd1-deficient primary astrocytes was ca. 60% of the wild-type cells and the activity was further decreased to ca. 25% in the presence of POCA. Compared to human skin fibroblasts, in which VLCFA β-oxidation is not significantly inhibited by POCA, approximately one-third of the overall VLCFA β-oxidation was inhibited in both types of astrocytic cells. These results suggest that VLCFA is indeed β-oxidized in ABCD1-dependent pathway, but the ABCD1-independent peroxisomal and mitochondrial β-oxidation pathways significantly contribute to VLCFA β-oxidation in astrocytic cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily D, Member 1
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Animals
  • Astrocytes / metabolism*
  • Cell Line, Tumor
  • Cells, Cultured
  • Epoxy Compounds / pharmacology
  • Fatty Acids / metabolism*
  • Fibroblasts / metabolism
  • Gene Silencing
  • Humans
  • Mice
  • Mitochondria / metabolism
  • Oxidation-Reduction
  • Peroxisomes / metabolism

Substances

  • ABCD1 protein, human
  • ATP Binding Cassette Transporter, Subfamily D, Member 1
  • ATP-Binding Cassette Transporters
  • Epoxy Compounds
  • Fatty Acids
  • ethyl 2-(5-(4-chlorophenyl)pentyl)oxiran-2-carboxylate