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En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Total nitrogen oxide following exercise testing reflects endothelial function and discriminates health status
Jason D Allen1, Frederick R Cobb, William E Kraus
1Department of Medicine, Duke University Medical Center, Center for Living Campus, DUMC 3022, Durham, NC 27710, USA. j.d.allen@duke.edu <j.d.allen@duke.edu>
Free Radical Biology & Medicine
|August 10, 2006
Summary
Plasma nitric oxide metabolites (NOx) can differentiate cardiovascular disease status and improve with exercise. Measuring NOx after exercise may offer a new clinical tool for assessing vascular health and disease progression.
Area of Science:
- Cardiovascular Physiology
- Biomarker Discovery
- Exercise Science
Background:
- Nitric oxide (NO) is crucial for vascular health but difficult to measure directly.
- Total nitrogen oxides (NOx) are stable alternatives, but background levels complicate disease detection.
- Existing measures of endothelial function and exercise capacity have limitations.
Purpose of the Study:
- To evaluate the clinical value of plasma NOx in distinguishing between healthy, increased cardiovascular risk, and established cardiovascular disease (CVD) subjects.
- To assess the relationship between plasma NOx, exercise capacity (VO2peak), and brachial artery reactivity (BAR).
- To determine if exercise training improves NOx levels and vascular function in at-risk individuals.
Main Methods:
- Plasma NOx levels were measured in healthy, increased risk, and CVD groups at rest, peak exercise, and recovery.
- Brachial artery reactivity (BAR) was assessed using forearm occlusion/hyperemia.
- Maximal graded exercise tests (GXT) were performed.
- A subset of at-risk individuals underwent a 6-month exercise training program.
Main Results:
- Healthy individuals showed a significant increase in NOx from rest to recovery, unlike the other groups.
- Brachial artery reactivity (BAR) was significantly higher in healthy individuals compared to CVD patients.
- A strong positive correlation was found between VO2peak and NOx levels during exercise recovery (r = 0.71, P < 0.01).
- Following exercise training, at-risk individuals showed significant improvements in VO2peak, BAR, and recovery NOx levels.
Conclusions:
- Plasma NOx levels measured after a graded exercise test can effectively discriminate cardiovascular disease status.
- Post-exercise NOx levels correlate with endothelial function (BAR) and exercise capacity (VO2peak).
- Exercise training favorably impacts plasma NOx levels, endothelial function, and exercise capacity in individuals at increased cardiovascular risk.
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