The Study On The Changes Of MPO, GSH-px Pre And Pro The Fat-loading On The Relationship With Atherosclerosis

Objective:We researched the changes of myeloperoxidas(MPO) and glutathione peroxidase(GSH-px) pre and pro fat meal load during the process of atherosclerosis(ATH), and the relationship between it and atherosclerosis.Methods:Ten healthy male New Zealand white rabbits, weighing 2.5-3.0 kg, were fed with high-fat meal( containing 1% cholesterol, 10% egg yolk, 89% basal diet) for 12 weeks,and provided fat meal load(containing 2% cholesterol, 20% egg yolk, 78% basal diet) at the beginning, as well as in the 4th, 8th, and 12 th weeks. Blood samples were collected after fasting and at 2, 4, 6, and 8 h after fat meal load to detect MPO and GSH-px; ATH conditions in the abdominal aorta were observed ultrasonically. At W12, the animals were sacrificed and ATH conditions were detected by hematoxylin and eosin staining.Results:1. Changes of MPO pre and pro the fat meal load during the process of atherosclerosis With the progress of arteriosclerosis, the level of fasting MPO was increased in the12 th week(P<0.05), After fat meal load, MPO was significantly increased at 2th hour and then gradually decreased in the first and 12 th week. In the 4th and 8th week, MPO was decreased. We suggested that oxidative stress was gradually increased in the process of atherosclerosis, and was severe and clearly observed at 2h after fat meal load.2. Changes of GSH-px pre and pro the fat meal load during the process of atherosclerosis With the progress of arteriosclerosis, the level of fasting GSH-px was decreased in the4 th, 8th and 12 th week(P<0.05), the lowest in the 12 th week. After fat meal load, the level of GSH-px exhibited a trend of descend. GSH-px was decreased at 2th to 8th hour in first week, at 6th to 8th hour in the 4th week, at 4th to 8th hour in the 8th week, at 8th hour in the12 th week. We suggested that decreasing of GSH-px may be related to the progression of the lesion, and be significantly decreased after single fat meal load.3. Ultrasound inspection of abdominal aorta In the first week, all animals showed smooth instead of rough abdominal aortic wall and no IMT thickening; in 4th week, the abdominal aortic walls of all the experimental animals were rough, as well as different degrees of IMT thickening; in 8th week, animals exhibited obviously thickened IMT and small plaques formed on the abdominal aortic wall;in 12 th week, all animals exhibited plaques formed on the abdominal aortic wall.4. Correlation between the changes of MPO and ultrasound score(1)In the 4th week, was positive correlation.(2)In the 8th week, fasting was positive correlated, the rest was negative correlation.(3)In the 12 th week, there was negative correlation postprandial with 4th hour, the rest was positive correlation.5. Correlation between the changes of GSH-px and ultrasound score(1)In the 4th week, there was positive correlation postprandial with 6th hour, the rest was negative correlation.(2)In the 8th week, fasting was negative correlation, the rest was positive correlation.(3)In the 12 th week, there was negative correlation postprandial with 4th hour, the rest was positive correlation.6. Gross examination of abdominal aorta At the end of the experiment, gross examination demonstrated visible patches.7. Pathological examination of abdominal aorta The vascular intima was continuous and smooth, and the cells were arranged in order.In W12, the vascular endothelial cells swelled, and the smooth muscle cells were abnormally arranged, with a large number of foam cells.Conclusion:1. In the early stage of atherosclerosis, oxidative stress was increased after fat meal load at2 hour. With the progress of arteriosclerosis, oxidative stress was decreased after fat meal load. In each stage of atherosclerosis, antioxidant capacity was decreased after fat meal load(6-8 hour).2. In the fasting state, oxidative stress was decreased, antioxidant capacity was decreased.