Lipin-2 reduces proinflammatory signaling induced by saturated fatty acids in macrophages

J Biol Chem. 2012 Mar 30;287(14):10894-904. doi: 10.1074/jbc.M112.342915. Epub 2012 Feb 8.

Abstract

Lipin-2 is a member of the lipin family of enzymes, which are key effectors in the biosynthesis of lipids. Mutations in the human lipin-2 gene are associated with inflammatory-based disorders; however, the role of lipin-2 in cells of the immune system remains obscure. In this study, we have investigated the role of lipin-2 in the proinflammatory action of saturated fatty acids in murine and human macrophages. Depletion of lipin-2 promotes the increased expression of the proinflammatory genes Il6, Ccl2, and Tnfα, which depends on the overstimulation of the JNK1/c-Jun pathway by saturated fatty acids. In contrast, overexpression of lipin-2 reduces the release of proinflammatory factors. Metabolically, the absence of lipin-2 reduces the cellular content of triacylglycerol in saturated fatty acid-overloaded macrophages. Collectively, these studies demonstrate a protective role for lipin-2 in proinflammatory signaling mediated by saturated fatty acids that occurs concomitant with an enhanced cellular capacity for triacylglycerol synthesis. The data provide new insights into the role of lipin-2 in human and murine macrophage biology and may open new avenues for controlling the fatty acid-related low grade inflammation that constitutes the sine qua non of obesity and associated metabolic disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cytokines / biosynthesis
  • Enzyme Activation / drug effects
  • Fatty Acids / metabolism
  • Fatty Acids / pharmacology*
  • Humans
  • Inflammation / genetics
  • Inflammation / metabolism
  • Inflammation / pathology
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Macrophages / cytology*
  • Macrophages / drug effects*
  • Macrophages / metabolism
  • Mice
  • Monocytes / cytology
  • Nuclear Proteins / deficiency
  • Nuclear Proteins / metabolism*
  • Phosphatidate Phosphatase / deficiency
  • Phosphatidate Phosphatase / metabolism*
  • Signal Transduction / drug effects*
  • Transcription Factor AP-1 / metabolism
  • Triglycerides / metabolism
  • Up-Regulation / drug effects

Substances

  • Cytokines
  • Fatty Acids
  • LPIN2 protein, human
  • Nuclear Proteins
  • Transcription Factor AP-1
  • Triglycerides
  • JNK Mitogen-Activated Protein Kinases
  • Phosphatidate Phosphatase
  • Lipin 2 protein, mouse