AMP-activated protein kinase activation by 5-aminoimidazole-4-carbox-amide-1-β-D-ribofuranoside (AICAR) reduces lipoteichoic acid-induced lung inflammation

J Biol Chem. 2013 Mar 8;288(10):7047-52. doi: 10.1074/jbc.M112.413138. Epub 2013 Jan 15.

Abstract

Adenosine monophosphate-activated protein (AMP)-activated kinase (AMPK) is a highly conserved kinase that plays a key role in energy homeostasis. Activation of AMPK was shown to reduce inflammation in response to lipolysaccharide in vitro and in vivo. 5-Aminoimidazole-4-carbox-amide-1-β-D-ribofuranoside (AICAR) is intracellularly converted to the AMP analog ZMP, which activates AMPK. Lipoteichoic acid (LTA) is a major component of the cell wall of Gram-positive bacteria that can trigger inflammatory responses. In contrast to lipopolysaccharide, little is known on the effects of AMPK activation in LTA-triggered innate immune responses. Here, we studied the potency of AMPK activation to reduce LTA-induced inflammation in vitro and in lungs in vivo. Activation of AMPK in vitro reduced cytokine production in the alveolar macrophage cell line MH-S. In vivo, AMPK activation reduced LTA-induced neutrophil influx, as well as protein leak and cytokine/chemokine levels in the bronchoalveolar space. In conclusion, AMPK activation inhibits LTA-induced lung inflammation in mice.

MeSH terms

  • AMP-Activated Protein Kinases / metabolism*
  • Acetyl-CoA Carboxylase / metabolism
  • Aminoimidazole Carboxamide / analogs & derivatives*
  • Aminoimidazole Carboxamide / pharmacology
  • Animals
  • Blotting, Western
  • Bronchoalveolar Lavage Fluid / chemistry
  • Bronchoalveolar Lavage Fluid / cytology
  • Cell Line
  • Chemokines / metabolism
  • Enzyme Activation / drug effects
  • Female
  • Hypoglycemic Agents / pharmacology
  • Interleukin-6 / metabolism
  • Lipopolysaccharides
  • Macrophages / cytology
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Neutrophils / drug effects
  • Neutrophils / metabolism
  • Phosphorylation / drug effects
  • Pneumonia / chemically induced
  • Pneumonia / enzymology
  • Pneumonia / prevention & control*
  • Ribonucleotides / pharmacology*
  • Teichoic Acids
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Chemokines
  • Hypoglycemic Agents
  • Interleukin-6
  • Lipopolysaccharides
  • Ribonucleotides
  • Teichoic Acids
  • Tumor Necrosis Factor-alpha
  • Aminoimidazole Carboxamide
  • lipoteichoic acid
  • AMP-Activated Protein Kinases
  • Acetyl-CoA Carboxylase
  • AICA ribonucleotide