The effects of Eicosapentaenoic acid on the endothelium of the carotid artery of rabbits on a high-cholesterol diet
Sevil Cayli1,*, Leyla Sati1,*, Yasemin Seval-Celik1, M. Altug Tuncer2, Bengi Yaymaci2, Zafer Berkman3, Tuncay Altug4 and Ramazan Demir1
1Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, Antalya, Turkey, 2Departments of Cardiovascular Surgery and Cardiology, Kosuyolu State Hospital Kartal, Istanbul, 3Department of Neurosurgery, Faculty of Medicine, Namik Kemal University, Tekirdag, Turkey and 4Department of Medical Biology, Faculty of Medicine, Bilim University, Istanbul, Turkey
* These authors contributed equally to this work.
Offprint requests to: Prof. Dr. Ramazan Demir, Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, Antalya Turkey. E-mail: rdemir@akdeniz.edu.tr
This study is dedicated to our generous and compassionate mentor, Prof. Dr. Turkan Erbengi
Summary. The preventive and therapeutic effects of Eicosapentaenoic acid (EPA) on diet-induced hyperlipidemia in rabbits have been investigated. Eighteen New Zealand rabbits were randomly divided into three groups of 6 subjects each; experimental group-I (EG-I) was administered a cholesterol rich diet, experimental group-II (EG-II) was treated with EPA (300 mg/kg/d) following a cholesterol-rich diet and the control group (CG) had a standard diet. Blood samples were collected at day 0 and at the 4th and 12th weeks of EG-II to obtain serum levels of total cholesterol (TC), high density lipid-cholesterol (HDL-C), low density lipid-cholesterol (LDL-C) and triglyceride (TG). From each group tissue samples were collected from the carotid artery for immunohistochemistry and electron microscopy. Our results showed that EPA could significantly lower (p<0.001) serum TC, LDL-C, HDL-C and TG levels with a reduction of 35%; 55%; 44% and 51%, respectively. Scanning and transmission electron microscopy results revealed that endothelial damage was more prominent in EG-I when compared to EG-II. The ruptured endothelial lining and damaged cellular surface was increased in EG-I when compared to EG-II. Ultrastructural observations showed that after EPA treatment, the degeneration and cellular surface damage on the endothelium were also decreased.
These biochemical and ultrastructural results suggest that EPA is a potential drug which significantly lowers the serum lipid profile and partially repairs endothelial dysfunction due to hyperlipidemia. Histol Histopathol 25, 141-151 (2010)
Key words: EPA, Cholesterol, Atherosclerosis, Endothelium, Ultrastructure, Rabbit
DOI: 10.14670/HH-25.141