Nathalie Gaudreault, Ph.D.
Postdoctoral Scholar
Division of Research
Department of Surgery
UC Davis Medical Center

Protein kinase C (PKC) is known to contribute to microvascular leakage in disease states such as diabetes. However, the precise cellular and molecular mechanisms by which PKC alters vascular endothelial barrier functions are not fully understood. This is due, in part, to the technical difficulty in obtaining dynamic measurements of PKC subcellular localization and activity. We recently obtained a genetically encoded fluorescent reporter to monitor PKC translocation and activity in vascular endothelial cells. This reporter, targeted either to the cell membrane or to the cytosol, allows fluorescence resonance energy transfer (FRET) to be produced intramolecularly at distinct subcellular locations. Reporter phosphorylation by PKC modulates FRET emission, providing a real-time analysis for PKC dynamics. We thus quantify PKC activity under basal conditions and during treatment with PKC activators and inhibitors in cultured human endothelial cells derived from large vessels or exchange microvessels. With concomitant measurements of transendothelial electrical resistance and protein flux, we are able to correlate the spatiotemporal activation of PKC with endothelial permeability induced by various metabolites that have been implicated in the development of diabetic vascular complications.

Gaudreault N, Scriven DRL, Moore EDW. Asymmetric subcellular distribution of glucose transporters in the endothelium of small contractile arteries. Endothelium, 2006 13:335-342. In press

Gaudreault N, Scriven DR, Moore ED. Characterisation of glucose transporters in the intact coronary artery endothelium in rats: GLUT-2 upregulated by long-term hyperglycaemia. Diabetologia, 2004 Dec;47(12):2081-92.

Lagaud G, Gaudreault N, Moore ED, Van Breemen C, Laher I. Pressure-dependent myogenic constriction of cerebral arteries occurs independently of voltage-dependent activation. American Journal of Physiology (Heart Circ Physiol), 2002 Dec;283(6):H2187-95.

Gaudreault N, Santure M, Pitre M, Nadeau A, Marette A, Bachelard H. Effects of insulin on regional blood flow and glucose uptake in Wistar and Sprague-Dawley rats. Metabolism, 2001 Jan;50(1):65-73.