Abstract
Atherosclerosis is an inflammatory disease where activated immune cells are recruited into the artery wall forming artery plaques. Interferon-γ released by T-cells causes macrophage synthesis and release of 7,8-dihydroneopterin, an antioxidant and CD36 down-regulator. 7,8-Dihydroneopterin scavenging of superoxide and hypochlorite generates neopterin, whose measurement has been used as a marker for inflammation in cardiovascular disease. With low oxidative stress levels, 7,8-dihydroneopterin is likely to be the predominant product leading to an underestimate of macrophage activation when measuring neopterin alone. Here we measure both total-neopterin (7,8-dihydroneopterin plus neopterin) and neopterin along with IL-1β, in cardiovascular disease patients presenting with stroke. Plasma neopterin and total neopterin were measured by HPLC in 61 stroke patients undergoing carotid endarterectomy surgery and 61 age-matched controls. Plasma IL-1β was measured by ELISA. Neopterin, total-neopterin, and 7,8-dihydroneopterin were all significantly higher in carotid surgery patients than age-matched controls. Total-neopterin showed the greatest difference between patients and controls (p ≤ 0.001). There was no significant difference in IL-1β levels between the stroke patients and healthy controls. The study shows that macrophage inflammation is elevated in cardiovascular disease patients presenting with stroke and the measurement of total neopterin is a more effective indicator of macrophage activation than neopterin alone.