Project Abstract: Chris Pattillo, PhD

“Glutathione Reductive Stress Regulates Arteriogenesis”

The incidence of tissue ischemia resulting from progressive vascular occlusion is on the rise, and leads to
several cardiovascular pathologies characterized by arterial blockage such as peripheral artery disease.
Revascularization of tissue is time sensitive and essential to restore adequate blood flow. Decreases in
antioxidant capacity such as decreases in the reduced form of glutathione (GSH) concentrations and
corresponding increases in oxidant stress are hallmarks of disease progression and endothelial cell
dysfunction. Decreases in glutathione are thought to correspond with a linear increase in disease severity that
is a poorly understood relationship. The current proposal seeks to: (a) determine the influence of changing
GSH:GSSG levels on protein glutathionylation driving vascular endothelial growth factor receptor 2 (VEGFR2)
signaling in arteriogenesis, (b) determine the role of glutathionylation in oxidative and shear stress induced
endothelial cell NF-κB signaling, (c) study in vivo arteriogenesis in murine models that have mutations in the
GSH synthesis pathway, and are undergoing ligations to mimic acute and chronic peripheral artery disease,
and (d) restore proper diabetic arteriogenesis progression by stimulating a more reductive cellular environment
to improve endothelial cell function. We will test the central hypothesis that a critical balance between the
reductive and oxidative cellular environments drives optimal VEGFR2 signaling to mediate arteriogenic
remodeling in response to increased shear and oxidant stress. The proposed aims will utilize in vitro
cultures of endothelial cells isolated from our glutathione synthesis mutant murine animals to generate data
focusing on glutathionylation of protein driving VEGFR2 specific signaling. The proposed aims also include our
in vivo mouse models of arterial blockage as clinically relevant models of vascular remodeling. Specific Aim 1
will focus on determining the role of glutathionylation in VEGFR2 activation during endothelial cell arteriogenic
signaling. We will utilize in vitro cultures of endothelial cells isolated from our glutathione synthesis mutant
murine animals to study signaling. Specific Aim 2 will assess the role of the oxidative/reductive balance in
arteriogenesis remodeling in vivo. Here we will use our in vivo mouse models of arterial blockage.

Successful completion of this project will provide new insights into the mechanism by which glutathione
regulates arteriogenesis in a physiologic range of GSH:GSSG following arterial ligation. Such information could
be the basis for new intervention therapies developed to precisely control arteriogenesis following artery
blockage. Enhancing the vascular remodeling potential of tissue through manipulation of glutathione and
protein glutathionylation may represent a critical first step in attenuating tissue damage due to vascular
occlusion.

The Center for Redox Biology and Cardiovascular Disease is supported by the National Institute of General Medical Sciences of the National Institutes of Health under Award Number P20GM121307.