engleski

Expression of endothelial lipase in carotid plaques and endothelial lipase plasma levels in patients with symptomatic carotid disease

Clinical presentation of atherosclerosis is initiated by plaque destabilization due to a local inflammatory process. Endothelial lipase (EL) is a member of triglyceride lipase family which is likely to have an important role in plaque destabilization. The main objective of our study was to evaluate the relationship between the expression of EL in human carotid atherosclerotic plaque (HCAP) and serum level of EL with regard to plaque (in)stability and the incidence of symptoms. HCAP were collected from 66 patients with significant (>70%) stenosis of carotid artery undergoing carotid endarterectomy. Patients were grouped by the presence of symptoms (stroke, transient ischemic attack) and by histological features of plaque vulnerability (ulceration, intra plaque hemorrhage and/or thrombus). EL protein expression was determined by immunostaining and the intensity was assessed on a semi-quantitative scale (low: < 25%, high: >25% positive cells). Monocytes and macrophages were stained with a CD163 specific antibody. EL plasma protein levels were analyzed by ELISA method. Results: High EL staining was more prevalent in the symptomatic group (p=0, 028). In fibrous plaques EL immunostaining was weak and detected in endothelial layer. In contrary, in vulnerable plaques the EL immunostaining was more pronounced (p=0, 004) and localized between the necrotic core and the fibrous cap where macrophages dominated. EL plasma levels were increased in symptomatic patients irrespective to time of occurrence and localization of symptoms (p=0, 011). EL in HCAP might be a marker and/or promoter of plaque instability and HCAP- related symptomatology. EL plasma levels reflect the patient's overall susceptibility for cerebrovascular events.

endothelial lipase; plaque; stability; symptomatology; high-density lipoprotein; inflammation; atherosclerosis; macrophages

Rad je izrađena u okviru Znanstvenog projekta Republike Austrije (Austrian Science Foundation (FWF ; grant P19473-B05) 2005-2010) i Međunarodne suradnje Medicinskog fakulteta Sveučilišta u Zagrebu i Medicinskog Univerziteta u Grazu (Agreement on Co-operation between the University of Zagreb School of Medicine and Medical University of Graz concluded on February 21 2005. Project title: Expression of endothelial lipase and inflammatory molecules in human carotid atheroscelrotic plaques. Principal investigators: Professor Saša Frank (Graz) and Assistant Professor Vesna Degoricija (Zagreb) Duration: 2005-2010).