Brachial artery vasodilator function and systemic inflammation in the Framingham Offspring Study

Area of Science:

• Cardiovascular Science
• Vascular Biology
• Inflammation Research

Background:

• Traditional risk factors and inflammation disrupt vascular endothelium function, promoting atherosclerosis.
• Endothelial dysfunction involves increased leukocyte adhesion and reduced nitric oxide bioavailability.
• The interplay between risk factors, inflammation, and nitric oxide remains unclear.

Purpose of the Study:

• To investigate the hypothesis that inflammation impairs human endothelial function.
• To assess the relationship between inflammatory markers and endothelial function measures.

Main Methods:

• Evaluated 2701 Framingham Study participants (mean age 61).
• Measured brachial artery flow-mediated dilation and reactive hyperemia.
• Assessed serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), and monocyte chemotactic protein-1 (MCP-1).

Main Results:

• Flow-mediated dilation showed inverse correlations with CRP, IL-6, and sICAM-1, which became non-significant after adjusting for risk factors.
• Reactive hyperemia demonstrated inverse correlations with inflammation markers, attenuated by risk factor adjustment.
• Partial correlations of CRP, IL-6, and sICAM-1 with reactive hyperemia remained significant.

Conclusions:

• Findings support the hypothesis that risk factors induce inflammation, impairing vascular function.
• Inflammation did not show additional effects on flow-mediated dilation beyond traditional risk factors.
• Systemic inflammation, indicated by CRP, IL-6, and sICAM-1, may contribute to impaired forearm microvessel vasomotor function.