Role of calcium/calmodulin-dependent protein kinase II in the regulation of vascular smooth muscle cell migration

Rebecca R. Pauly, Claudio Bilato, Steven J. Sollott, Robert Monticone, Paul T. Kelly, Edward G. Lakatta, Michael T. Crow

Research output: Contribution to journalArticle

Abstract

Background: The migration of vascular smooth muscle cells (VSMCs) is a key event in the pathogenesis of many vascular diseases. We have previously shown that VSMC migration in response to platelet-derived growth factor (PDGF) is suppressed when cultured cells are growth-arrested and induced to differentiate. The present study was undertaken to elucidate the mechanism of this suppression. Methods and Results: While both proliferating and growth- arrested VSMCs upregulated expression of the immediate early response genes, c-fos and JE (monocyte chemoattractant protein 1), growth-arrested VSMCs exhibited much smaller changes in intracellular calcium in response to PDGF and failed to activate the calcium/calmodulin-dependent protein kinase II (CaM kinase II). Blocking calcium-calmodulin interactions (50 μmol/L W7) or the activation of CaM kinase II (10 μmol/L KN62) in proliferating cells blocked their migration by more than 90%, whereas inhibition of protein kinase C activation had no significant effect on migration. Pretreatment of growth-arrested VSMCs with the calcium ionophore ionomycin resulted in an approximately 2.5-fold activation of CaM kinase II and increased migration of growth-arrested cells to 84±6% that of proliferating cells. These effects of ionomycin were blocked by inhibitors of CaM kinase II. Constitutively activated (ie, calcium/calmodulin-independent) CaM kinase II introduced by gene transfection into growth-arrested cells significantly increased migration toward PDGF from <20% to >70% that of proliferating cells. Conclusions: These results demonstrate that activation of CaM kinase II is required for VSMC migration, that its activation in response to PDGF is suppressed in growth-arrested VSMCs, and that this suppression of CaM kinase II activation is responsible, in large part, for the failure of growth- arrested VSMCs to migrate toward PDGF.

Original languageEnglish (US)
Pages (from-to)1107-1115
Number of pages9
JournalCirculation
Volume91
Issue number4
DOIs
StatePublished - Feb 15 1995

Keywords

  • calcium
  • cells
  • muscles, smooth
  • platelet-derived factors
  • protein kinases

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Role of calcium/calmodulin-dependent protein kinase II in the regulation of vascular smooth muscle cell migration'. Together they form a unique fingerprint.

  • Cite this