Heparin cofactor II, a serine protease inhibitor, promotes angiogenesis via activation of the AMP-activated protein kinase-endothelial nitric-oxide synthase signaling pathway

J Biol Chem. 2012 Oct 5;287(41):34256-63. doi: 10.1074/jbc.M112.353532. Epub 2012 Aug 17.

Abstract

We previously clarified that heparin cofactor II (HCII), a serine proteinase inhibitor, exerts various protective actions on cardiovascular diseases in both experimental and clinical studies. In the present study, we aimed to clarify whether HCII participates in the regulation of angiogenesis. Male heterozygous HCII-deficient (HCII(+/-)) mice and male littermate wild-type (HCII(+/+)) mice at the age of 12-16 weeks were subjected to unilateral hindlimb ligation surgery. Laser speckle blood flow analysis showed that blood flow recovery in response to hindlimb ischemia was delayed in HCII(+/-) mice compared with that in HCII(+/+) mice. Capillary number, arteriole number, and endothelial nitric-oxide synthase (eNOS), AMP-activated protein kinase (AMPK), and liver kinase B1 (LKB1) phosphorylation in ischemic muscles were decreased in HCII(+/-) mice. Human purified HCII (h-HCII) administration almost restored blood flow recovery, capillary density, and arteriole number as well as phosphorylation levels of eNOS, AMPK, and LKB1 in ischemic muscles of HCII(+/-) mice. Although treatment with h-HCII increased phosphorylation levels of eNOS, AMPK, and LKB1 in human aortic endothelial cells (HAECs), the h-HCII-induced eNOS phosphorylation was abolished by compound C, an AMPK inhibitor, and by AMPK siRNA. In a similar fashion, tube formation, proliferation, and migration of HAECs were also promoted by h-HCII treatment and were abrogated by pretreatment with compound C. HCII potentiates the activation of vascular endothelial cells and the promotion of angiogenesis in response to hindlimb ischemia via an AMPK-eNOS signaling pathway. These findings suggest that HCII is a novel therapeutic target for treatment of patients with peripheral circulation insufficiency.

MeSH terms

  • AMP-Activated Protein Kinases / metabolism*
  • Animals
  • Aorta / cytology
  • Aorta / metabolism
  • Cell Movement / drug effects
  • Cell Movement / physiology
  • Endothelial Cells / cytology
  • Endothelial Cells / metabolism
  • Heparin Cofactor II / metabolism*
  • Heparin Cofactor II / pharmacology
  • Humans
  • Male
  • Mice
  • Mice, Mutant Strains
  • Neovascularization, Physiologic / drug effects
  • Neovascularization, Physiologic / physiology*
  • Nitric Oxide Synthase Type III / metabolism*
  • Signal Transduction / drug effects
  • Signal Transduction / physiology*

Substances

  • SERPIND1 protein, human
  • Serpind1 protein, mouse
  • Heparin Cofactor II
  • NOS3 protein, human
  • Nitric Oxide Synthase Type III
  • Nos3 protein, mouse
  • AMP-Activated Protein Kinases