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Peroxisomal lipid synthesis regulates inflammation by sustaining neutrophil membrane phospholipid composition and viability.

ABSTRACT: Fatty acid synthase (FAS) is altered in metabolic disorders and cancer. Conventional FAS null mice die in utero, so effects of whole-body inhibition of lipogenesis following development are unknown. Inducible global knockout of FAS (iFASKO) in mice was lethal due to a disrupted intestinal barrier and leukopenia. Conditional loss of FAS was associated with the selective suppression of granulopoiesis without disrupting granulocytic differentiation. Transplantation of iFASKO bone marrow into wild-type mice followed by Cre induction resulted in selective neutrophil depletion, but not death. Impaired lipogenesis increased ER stress and apoptosis in neutrophils by preferentially decreasing peroxisome-derived membrane phospholipids containing ether bonds. Inducible global knockout of PexRAP, a peroxisomal enzyme required for ether lipid synthesis, also produced neutropenia. FAS knockdown in neutrophil-like HL-60 cells caused cell loss that was partially rescued by ether lipids. Inhibiting ether lipid synthesis selectively constrains neutrophil development, revealing an unrecognized pathway in immunometabolism.

SUBMITTER: Lodhi IJ

PROVIDER: S-EPMC4287274 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Peroxisomal lipid synthesis regulates inflammation by sustaining neutrophil membrane phospholipid composition and viability.

Lodhi Irfan J IJ Wei Xiaochao X Yin Li L Feng Chu C Adak Sangeeta S Abou-Ezzi Grazia G Hsu Fong-Fu FF Link Daniel C DC Semenkovich Clay F CF

Cell metabolism 20150101 1

Fatty acid synthase (FAS) is altered in metabolic disorders and cancer. Conventional FAS null mice die in utero, so effects of whole-body inhibition of lipogenesis following development are unknown. Inducible global knockout of FAS (iFASKO) in mice was lethal due to a disrupted intestinal barrier and leukopenia. Conditional loss of FAS was associated with the selective suppression of granulopoiesis without disrupting granulocytic differentiation. Transplantation of iFASKO bone marrow into wild-t ...[more]

PMID: 25565205

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Peroxisomal lipid synthesis regulates inflammation by sustaining neutrophil membrane phospholipid composition and viability.

Publications

Peroxisomal lipid synthesis regulates inflammation by sustaining neutrophil membrane phospholipid composition and viability.

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