Neutrophil serine proteases and their endogenous inhibitors in coronary artery ectasia patients

Area of Science:

• Cardiovascular Medicine
• Biochemistry
• Immunology

Background:

• Coronary artery ectasia (CAE) is a condition where coronary arteries abnormally widen.
• Proteolytic enzymes are hypothesized to play a role in the pathogenesis of CAE.
• Neutrophils and their associated proteases are key players in inflammatory and tissue remodeling processes.

Purpose of the Study:

• To investigate the involvement of neutrophils, neutrophil serine proteases (NSPs), and their inhibitors in the pathological mechanisms of CAE.
• To compare levels of NSPs, their inhibitors, and neutrophil activation markers in patients with CAE, coronary artery disease (CAD), and healthy controls.

Main Methods:

• A comparative study involving 30 patients with CAE, 30 with CAD, and 29 controls.
• Measurement of circulating levels of key NSPs (HNE, CG, PR3), soluble elastin (sElastin), NSP inhibitors (α1-PI, α2-MG, SLPI, elafin), and neutrophil activation markers (myeloperoxidase, lactoferrin).
• Analysis of classic neutrophil activators (TNF-α, IL-8, bacterial endotoxin) in different groups.

Main Results:

• Elevated levels of human neutrophil elastase (HNE), cathepsin G (CG), and soluble elastin (sElastin) were observed in the CAE group.
• Significantly increased levels of α1-protease inhibitor (α1-PI) and α2-macroglobulin (α2-MG) were found in CAE patients.
• Higher concentrations of myeloperoxidase and lactoferrin indicated increased neutrophil activation in the CAE group.

Conclusions:

• Neutrophils, through the release of NSPs, may contribute to the destruction of the vessel's extracellular matrix in CAE.
• The findings suggest a non-classical mechanism of neutrophil involvement in the development of coronary ectasia.