Abscisic acid released by human monocytes activates monocytes and vascular smooth muscle cell responses involved in atherogenesis

J Biol Chem. 2009 Jun 26;284(26):17808-18. doi: 10.1074/jbc.M809546200. Epub 2009 Mar 30.


Abscisic acid (ABA) is a phytohormone recently identified as a new endogenous pro-inflammatory hormone in human granulocytes. Here we report the functional activation of human monocytes and vascular smooth muscle cells by ABA. Incubation of monocytes with ABA evokes an intracellular Ca2+ rise through the second messenger cyclic ADP-ribose, leading to NF-kappaB activation and consequent increase of cyclooxygenase-2 expression and prostaglandin E2 production and enhanced release of MCP-1 (monocyte chemoattractant protein-1) and of metalloprotease-9, all events reportedly involved in atherogenesis. Moreover, monocytes release ABA when exposed to thrombin-activated platelets, a condition occurring at the injured vascular endothelium; monocyte-derived ABA behaves as an autocrine and paracrine pro-inflammatory hormone-stimulating monocyte migration and MCP-1 release, as well as vascular smooth muscle cells migration and proliferation. These results, and the presence of ABA in human arterial plaques at a 10-fold higher concentration compared with normal arterial tissue, identify ABA as a new signal molecule involved in the development of atherosclerosis and suggest a possible new target for anti-atherosclerotic therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / pharmacology*
  • Aorta / cytology
  • Aorta / metabolism
  • Atherosclerosis / metabolism*
  • Atherosclerosis / pathology
  • Blotting, Western
  • Calcium / metabolism
  • Cell Movement
  • Cell Proliferation
  • Cells, Cultured
  • Chemokine CCL2 / metabolism
  • Cyclooxygenase 2 / metabolism
  • Dinoprostone / metabolism
  • Hemostatics / pharmacology
  • Humans
  • Monocytes / drug effects*
  • Monocytes / metabolism
  • Muscle, Smooth, Vascular / drug effects*
  • Muscle, Smooth, Vascular / metabolism
  • NF-kappa B / metabolism
  • Plant Growth Regulators / pharmacology*
  • Platelet Activation / drug effects
  • Protein Transport
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Second Messenger Systems
  • Thrombin / pharmacology


  • Chemokine CCL2
  • Hemostatics
  • NF-kappa B
  • Plant Growth Regulators
  • RNA, Messenger
  • Abscisic Acid
  • Cyclooxygenase 2
  • PTGS2 protein, human
  • Thrombin
  • Dinoprostone
  • Calcium