Shear stress regulation of Krüppel-like factor 2 expression is flow pattern-specific.

Biochem Biophys Res Commun

Department of Bioengineering, Whitaker Institute of Biomedical Engineering, University of California-San Diego, La Jolla, CA 92093-0412, USA.

Published: March 2006

Flow patterns in blood vessels contribute to focal distribution of atherosclerosis; the underlying mechanotransduction pathways remain to be investigated. We demonstrate that different flow patterns elicit distinct responses of Krüppel-like factor-2 (KLF2) in endothelial cells (ECs) in vitro and in vivo. While pulsatile flow with a significant forward direction induced sustained expression of KLF2 in cultured ECs, oscillatory flow with little forward direction caused prolonged suppression after a transient induction. The suppressive effect of oscillatory flow was Src-dependent. Immunohistochemical studies on ECs at arterial branch points revealed that KLF2 protein levels were related to local hemodynamics. Such flow-associated expression patterns were also demonstrated in a rat aortic restenosis model. Inhibition of KLF2 with siRNA sensitized ECs to oxidized LDL-induced apoptosis, indicating a protective role of KLF2. In conclusion, differential regulation of KLF2 may mediate the distinct vascular effects induced by various patterns of shear stress.

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http://dx.doi.org/10.1016/j.bbrc.2006.01.089DOI Listing

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