Abstract 12280: Endothelial Cell Inflammation and Antioxidant Capacity are Associated With Exercise Performance and Microcirculation in Patients With Peripheral Artery Disease
Background: We determined whether exercise performance and lower extremity microcirculation were associated with endothelial cell inflammation, oxidative stress, and apoptosis, and with circulating biomarkers of inflammation and antioxidant capacity. Methods: One hundred sixty symptomatic patients with PAD were characterized on the endothelial effects of circulating factors present in the sera using a cell culture-based bioassay on primary human arterial endothelial cells. Patients were further evaluated on circulating inflammatory and vascular biomarkers, physical examination, medical history, exercise performance measured during treadmill evaluation by peak walking time (PWT), and claudication onset time (COT), and lower extremity microcirculation measured by calf muscle hemoglobin oxygen saturation (StO 2 ) during treadmill exercise. Results: In the multivariate regression model for PWT, the significant independent variables included ankle-brachial index (p<0.001), age (p=0.017), hydroxyl radical antioxidant capacity (HORAC) (p=0.008), and endothelial cell NF-κB activity (p=0.015). In the multivariate regression model for COT, the significant independent variable was endothelial cell NF-κB activity (p=0.013). In the multivariate analyses for the average rate of decline in calf muscle StO 2 during exercise, the significant independent variables included body mass index (p<0.001) and HORAC (p=0.024). Conclusions: Endothelial cell inflammation and circulating biomarkers of inflammation and antioxidant capacity are significant factors for exercise performance and microcirculation of the ischemic calf musculature during exercise. The clinical implication is that interventions designed to alleviate endothelial cell inflammation and circulating inflammatory biomarkers, such as antioxidant therapy, may improve exercise performance of symptomatic patients with PAD.