Early Biomarker Sought for Atherosclerosis
A proinflammatory protein that is overexpressed in endothelial cells (ECs) from patients with coronary artery disease contributes to the early development of atherosclerosis.
Blood levels of this protein increase in patients with cardiovascular disease as well as in people with complications related to diabetes, obesity and cancer in which the small blood vessels are damaged, as all of these diseases are associated with chronic inflammation.
Scientists at the Montreal Heart Institute (QC, Canada) measured the plasma levels of angiopoietin-like protein 2 (angptl2) in an animal model and then in 11 coronary artery disease (CAD) patients and six healthy volunteers. Other techniques included in the study were Western blots to measure the secretion of endogenous angptl2 into the culture medium; fluorescent immunocytochemistry; and ribonucleic acid (RNA) extraction and real-time quantitative polymerase chain reaction (qPCR).
The qPCR reactions were performed using aMxPro3000 platform (Agilent; Mississauga, ON, Canada) and circulating human angptl2 levels were measured using a commercial enzyme-linked immunosorbent assay kit (ELISA) (antibodies-online; Atlanta, GA USA). Compared with age-matched male healthy volunteers’ plasma angptl2 levels were significantly higher in CAD patients at 6.02 ± 1.33 ng/mL, while for the healthy subjects it was 1.00 ± 0.18 ng/mL. The presence of CAD was documented by a history of angina in five of 11 patients, infarct in six of 11, previous dilatation in three of 11, or coronary bypass in 1 patient.
Eric Thorin, PhD, the senior author, said, “Although much work remains to be done to broaden our knowledge of this protein’s mechanisms of action, angiopoietin-like protein 2 may represent an early biomarker not only to prevent vascular damage, but also to predict atherosclerotic disease.” Anil Nigam, MD, a cardiologist and coauthor of the study added, “Prevention is the ideal solution to delay the onset of atherosclerosis, and an early blood marker such as angptl2, if future clinical studies confirm this finding, will serve as an important tool to identify at-risk subjects who do not present with any symptoms of atherosclerotic disease.” The study was published on May 10, 2013, in the Journal of the American Heart Association.